摘要:

Journal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates - Formerly ARAAS) JAAS Editorial Board* Chairman: J. M. Ottaway (Glasgow, UK) J. Brew (London, UK) M. S. Cresser (Aberdeen, UK) L. C. Ebdon (Plymouth, UK) D. L. Miles (Wallingford, UK) B. L. Sharp (Aberdeen, UK) M. Thompson (London, UK) A. M. Ure (Aberdeen, UK) *The JAAS Editorial Board reports to the Analytical Editorial Board, Chairman J. D. R. Thomas (Cardiff, UK) JAAS Advisory Board F. C. A d a m (Antwerp, Belgium) R. M. Barnes (Amherst, MA, USA) L. Bezur (Budapest, Hungary) R. F. Browner (Atlanta, GA, USA) S. Caroli (Rome, Italy) L. de Galan (Delft, The Netherlands) J. B. Dawson (Leeds, UK) K. Dittrich (Leipzig, GDR) W. Frech (Umed, Sweden) K. Fuwa (Tokyo, Japan) A. L. Gray (Guildford, UK) S.Greenfield (Loughborough, UK) G. M. Hieftje (Bloomington, IN, USA) G. Horlick (Edmonton, Canada) J. J. LaBrecque (Caracas, Venezuela) J. M. Mermet (Villeurbanne, France) Ni Zhe-ming (Beijing, China) N. Omenetto (lspra, Italy) E. Pl5ko (Bratislava, Czechoslovakia) R. Sturgeon (Ottawa, Canada) A. Walsh,,,K. B. (Victoria, Australia) B. Welz (Uberlingen, FRG) T. S. West (Aberdeen, UK) Atomic Spectrometry Updates Editorial Board Chairman: *M. S. Cresser (Aberdeen, UK) R. M. Barnes (Amherst, MA, USA) N. W. Barnett (Plymouth, UK) *J. Brew (London, UK) *A. A. Brown (Cambridge, UK) J. C. Burridge (Aberdeen, UK) J. B. Dawson (Leeds, UK) *L. C. Ebdon (Plymouth, UK) H. J. Ellis (Ross-on-Wye, UK) J. Fijalkowski (Warsaw, Poland) D. J. Halls (Glasgow, UK) S. J. Haswell (London, UK) *D.A. Hickman (London, UK) G. M. Hieftje (Bloomington, IN, USA) H. Hughes (Anglesey, UK) P. N. Keliher (Villanova, PA, USA) K. Kitagawa (Nagoya, Japan) C. W. McLeod (Sheffield, UK) K. W. Jackson (Saskatoon, Canada) F. J. M. J. Maessen (Amsterdam, The Nether- *D. Littlejohn (Glasgow, UK) lands) *J. Marshall (Middlesbrough, UK) J. M. Mermet (Villeurbanne, France) E. Norval (Pretoria, South Africa) I. Novotny (Bmo, Czechoslovakia) P. E. Paus (Oslo, Norway) P. R. Poole (Hamilton, New Zealand) T. C. Rains (Washington, DC, USA) J. M. Rooke (Leeds, UK) G. Rossi (lspra, Italy) I. RubeSka (Prague, Czechoslovakia) *B. L. Sharp (Aberdeen, UK) W. Slavin (Norwalk, CT, USA) R. D. Snook (London, UK) R. Stephens (Halifax, Canada) J. Stupar (Ljubljana, Yugoslavia) A.Taylor (Guildford, UK) M. Thompson (London, UK) *A. M. Ure,(Aberdeen, UK) B. Welz (Uberlingen, FRG) J. B. Willis (Victoria, Australia) *D. L. Miles (Wallingford, UK) *J. M. Ottaway (Glasgow, UK) *Members of the ASU Executive Committee ~~ Editor, JAAS: Judith Brew The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN, UK. Telephone 01-734 9864. Telex No. 268001 US Associate Editor, JAAS: Dr. J. M. Harnly US Department of Agriculture, Beltsville Human Nutrition Research Center, BLDG 161, BARC-EAST, Beltsville, MD 20705, USA. Telephone 301 -344-2569 Advertisements: Advertisement Department, The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN. Telephone 01-437 8656. Telex No. 268001 Journal ofAnalytical Atomic Spectrometry (JAASI (ISSN 0267-9477) is published bimonthly by The Royal Society of Chemistry, Burlington House, London W1V OBN, UK.All orders accompanied with payment should be sent directly to The Royal Society of Chemistry, The Distribution Centre, Blackhorse Road, Letchworth, Herts. SG6 1HN. UK. 1986 Annual subscription rate UK f165.00, Rest of World €182.00, USA $319.00. Air freight and mailing in the USA by Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003. USA Postmaster: send address changes to Journal o f Analytical Atomic Spectrometry (JAAS), Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003. Second class postage pending at Jamaica, NY 11431. All other despatches outside the UK by Bulk Airmail within Europe, Accelerated Surface Post outside Europe.PRINTED IN THE UK. @The Royal Society of Chemistry, 1986. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form, or by any means, electronic, mechanical, photographic, recording, or otherwise, without the prior permission of the publishers. nformation for Authors :uII details of how to submit material for )ublication in JAASare given in the Instructions o Authors in Issue 1. Separate copies are ivailable on request. The Journal of Analytical Atomic Spectrometry JAAS) is an international journal for the publi- :ation of original research papers, short papers, :ommunications and letters concerned with the levelopment and analytical application of itomic spectrometric techniques.The journal Nil1 be published bimonthly, will include com- Jrehensive reviews of specific topics of interest :o practising atomic spectroscopists and will ncorporate the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy (ARAAS). Manuscripts intended for publication must describe original work related to atomic spec- trometric analysis. Papers on all aspects of the subject will be accepted, including fundamental studies, novel instrument developments and practical analytical applications. As well as AAS, AES and AFS, papers will be welcomed on atomic mass spectrometry and X-ray fluoresc- enceiemission spectrometry. Papers describing the measurement of molecular species where these relate to the characterisation of sources normally used for the production of atoms, or are concerned, for example, with indirect methods of analysis, will also be acceptable for publication.Papers describing the development and applications of hybrid techniques (e.g., GC-coupled AAS and HPLC - ICP) will be parti- cularly welcome. Manuscripts on other subjects of direct interest to atomic spectroscopists, including sample preparation and dissolution and analyte preconcentration procedures, as well as the statistical interpretation and use of atomic spectrometric data will also be accept- able for publication. There is no page charge. The following types of papers will be con- Full papers, describing original work. Short papers, also describing original work, but of limited breadth of subject matter.Communications, which must be on an urgent matter and be of obvious scientific importance. Communications should not be simple claims for priority: this facility for rapid publication is intended for brief descriptions of work that has progressed to a stage at which it is likely to be valuable to workers faced with similar problems. Reviews, which must be a critical evaluation of the existing state of knowledge on a parti- cular facet of analytical atomic spectrometry. Every paper (except Communications) will be submitted to at least two referees, by whose advice the Editorial Board of JAAS will be guided as to its acceptance or rejection. Papers that are accepted must not be published else- where except by permission. Submission of a manuscript will be regarded as an undertaking that the same material is not being considered for publication by another journal.Manuscripts (three copies typed in double spac- ing) should be addressed to: sidered. Editor, JAAS Judith Brew The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN, UK US Associate Editor, JAAS Dr. J. M. Harnly US Department of Agriculture, Beltsville Human Nutrition Research Center, 8LDG 161, BARC-EAST, Beltsville, MD 20705, USA or All queries relating to the presentation and submission of papers, and any correspondence regarding accepted papers and proofs, should be directed to the Editor or US Editor (addresses as above). MembersoftheJAASEditorial Board (who may be contacted directly or via the Editorial Office) would welcome comments, suggestions and advice on general policy mat- ters concerning JAAS.Fifty reprints of each published contribution are supplied free of charge.Journal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates - Formerly ARAAS) JAAS Editorial Board* Chairman: J. M. Ottaway (Glasgow, UK) J. Brew (London, UK) M. S. Cresser (Aberdeen, UK) L. C. Ebdon (Plymouth, UK) D. L. Miles (Wallingford, UK) B. L. Sharp (Aberdeen, UK) M. Thompson (London, UK) A. M. Ure (Aberdeen, UK) *The JAAS Editorial Board reports to the Analytical Editorial Board, Chairman J. D. R. Thomas (Cardiff, UK) JAAS Advisory Board F. C. A d a m (Antwerp, Belgium) R. M. Barnes (Amherst, MA, USA) L. Bezur (Budapest, Hungary) R. F. Browner (Atlanta, GA, USA) S. Caroli (Rome, Italy) L.de Galan (Delft, The Netherlands) J. B. Dawson (Leeds, UK) K. Dittrich (Leipzig, GDR) W. Frech (Umed, Sweden) K. Fuwa (Tokyo, Japan) A. L. Gray (Guildford, UK) S. Greenfield (Loughborough, UK) G. M. Hieftje (Bloomington, IN, USA) G. Horlick (Edmonton, Canada) J. J. LaBrecque (Caracas, Venezuela) J. M. Mermet (Villeurbanne, France) Ni Zhe-ming (Beijing, China) N. Omenetto (lspra, Italy) E. Pl5ko (Bratislava, Czechoslovakia) R. Sturgeon (Ottawa, Canada) A. Walsh,,,K. B. (Victoria, Australia) B. Welz (Uberlingen, FRG) T. S. West (Aberdeen, UK) Atomic Spectrometry Updates Editorial Board Chairman: *M. S. Cresser (Aberdeen, UK) R. M. Barnes (Amherst, MA, USA) N. W. Barnett (Plymouth, UK) *J. Brew (London, UK) *A. A. Brown (Cambridge, UK) J. C. Burridge (Aberdeen, UK) J.B. Dawson (Leeds, UK) *L. C. Ebdon (Plymouth, UK) H. J. Ellis (Ross-on-Wye, UK) J. Fijalkowski (Warsaw, Poland) D. J. Halls (Glasgow, UK) S. J. Haswell (London, UK) *D. A. Hickman (London, UK) G. M. Hieftje (Bloomington, IN, USA) H. Hughes (Anglesey, UK) P. N. Keliher (Villanova, PA, USA) K. Kitagawa (Nagoya, Japan) C. W. McLeod (Sheffield, UK) K. W. Jackson (Saskatoon, Canada) F. J. M. J. Maessen (Amsterdam, The Nether- *D. Littlejohn (Glasgow, UK) lands) *J. Marshall (Middlesbrough, UK) J. M. Mermet (Villeurbanne, France) E. Norval (Pretoria, South Africa) I. Novotny (Bmo, Czechoslovakia) P. E. Paus (Oslo, Norway) P. R. Poole (Hamilton, New Zealand) T. C. Rains (Washington, DC, USA) J. M. Rooke (Leeds, UK) G. Rossi (lspra, Italy) I. RubeSka (Prague, Czechoslovakia) *B.L. Sharp (Aberdeen, UK) W. Slavin (Norwalk, CT, USA) R. D. Snook (London, UK) R. Stephens (Halifax, Canada) J. Stupar (Ljubljana, Yugoslavia) A. Taylor (Guildford, UK) M. Thompson (London, UK) *A. M. Ure,(Aberdeen, UK) B. Welz (Uberlingen, FRG) J. B. Willis (Victoria, Australia) *D. L. Miles (Wallingford, UK) *J. M. Ottaway (Glasgow, UK) *Members of the ASU Executive Committee ~~ Editor, JAAS: Judith Brew The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN, UK. Telephone 01-734 9864. Telex No. 268001 US Associate Editor, JAAS: Dr. J. M. Harnly US Department of Agriculture, Beltsville Human Nutrition Research Center, BLDG 161, BARC-EAST, Beltsville, MD 20705, USA. Telephone 301 -344-2569 Advertisements: Advertisement Department, The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN.Telephone 01-437 8656. Telex No. 268001 Journal ofAnalytical Atomic Spectrometry (JAASI (ISSN 0267-9477) is published bimonthly by The Royal Society of Chemistry, Burlington House, London W1V OBN, UK. All orders accompanied with payment should be sent directly to The Royal Society of Chemistry, The Distribution Centre, Blackhorse Road, Letchworth, Herts. SG6 1HN. UK. 1986 Annual subscription rate UK f165.00, Rest of World €182.00, USA $319.00. Air freight and mailing in the USA by Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003. USA Postmaster: send address changes to Journal o f Analytical Atomic Spectrometry (JAAS), Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003.Second class postage pending at Jamaica, NY 11431. All other despatches outside the UK by Bulk Airmail within Europe, Accelerated Surface Post outside Europe. PRINTED IN THE UK. @The Royal Society of Chemistry, 1986. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form, or by any means, electronic, mechanical, photographic, recording, or otherwise, without the prior permission of the publishers. nformation for Authors :uII details of how to submit material for )ublication in JAASare given in the Instructions o Authors in Issue 1. Separate copies are ivailable on request. The Journal of Analytical Atomic Spectrometry JAAS) is an international journal for the publi- :ation of original research papers, short papers, :ommunications and letters concerned with the levelopment and analytical application of itomic spectrometric techniques.The journal Nil1 be published bimonthly, will include com- Jrehensive reviews of specific topics of interest :o practising atomic spectroscopists and will ncorporate the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy (ARAAS). Manuscripts intended for publication must describe original work related to atomic spec- trometric analysis. Papers on all aspects of the subject will be accepted, including fundamental studies, novel instrument developments and practical analytical applications. As well as AAS, AES and AFS, papers will be welcomed on atomic mass spectrometry and X-ray fluoresc- enceiemission spectrometry.Papers describing the measurement of molecular species where these relate to the characterisation of sources normally used for the production of atoms, or are concerned, for example, with indirect methods of analysis, will also be acceptable for publication. Papers describing the development and applications of hybrid techniques (e.g., GC-coupled AAS and HPLC - ICP) will be parti- cularly welcome. Manuscripts on other subjects of direct interest to atomic spectroscopists, including sample preparation and dissolution and analyte preconcentration procedures, as well as the statistical interpretation and use of atomic spectrometric data will also be accept- able for publication. There is no page charge.The following types of papers will be con- Full papers, describing original work. Short papers, also describing original work, but of limited breadth of subject matter. Communications, which must be on an urgent matter and be of obvious scientific importance. Communications should not be simple claims for priority: this facility for rapid publication is intended for brief descriptions of work that has progressed to a stage at which it is likely to be valuable to workers faced with similar problems. Reviews, which must be a critical evaluation of the existing state of knowledge on a parti- cular facet of analytical atomic spectrometry. Every paper (except Communications) will be submitted to at least two referees, by whose advice the Editorial Board of JAAS will be guided as to its acceptance or rejection. Papers that are accepted must not be published else- where except by permission. Submission of a manuscript will be regarded as an undertaking that the same material is not being considered for publication by another journal. Manuscripts (three copies typed in double spac- ing) should be addressed to: sidered. Editor, JAAS Judith Brew The Royal Society of Chemistry, Burlington House, Piccadilly, London W1V OBN, UK US Associate Editor, JAAS Dr. J. M. Harnly US Department of Agriculture, Beltsville Human Nutrition Research Center, 8LDG 161, BARC-EAST, Beltsville, MD 20705, USA or All queries relating to the presentation and submission of papers, and any correspondence regarding accepted papers and proofs, should be directed to the Editor or US Editor (addresses as above). MembersoftheJAASEditorial Board (who may be contacted directly or via the Editorial Office) would welcome comments, suggestions and advice on general policy mat- ters concerning JAAS. Fifty reprints of each published contribution are supplied free of charge.

ISSN:0267-9477    

DOI:10.1039/JA98601FX017

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JASPE2 l(5) 313-400,121R-168R (1986) October 1986 Journal of Analytical Atomic Spectrometry Including Atomic Spectrometry Updates CONTENTS NEWS AND VIEWS 313 EditoriaCJ. M. Ottaway 314 3t7 Conference Reports 320 ASU Highlights 321 Book Review 321 321 Conferences and Meetings 324 Papers in Future Issues Atomic Spectrometry Viewpoint-L. Ebdon and R. C. Hutton RSC Awards 1986: Analytical Spectroscopy PAPERS 325 331 337 343 349 355 359 365 369 373 379 383 387 39 1 397 Spatial Emission Characteristics and Excitation Mechanisms in the Inductively Coupled Plasma. A Review-John Davies, Richard D. Snook Multi-element Analysis of Ferrotungsten by Inductively Coupled Plasma Atomic Emission Spectrometry-Ivan H lavate k, I rena H lavatkova Electrothermal Vaporisation Sample Introduction into an Atmospheric Pressure Helium Microwave-induced Plasma for the Determination of Iodine in Hydrochloric Acid- Neil W.Barnett, (the late) Gordon F. Kirkbright Inductively Coupled Plasma Atomic FluorescenCe Spectrometric Determination of Cadmium, Copper, Iron, Lead, Manganese and Zinc-Richard F. Sanzolone Improved Determination of Cadmium in Blood by Flame Atomic FluorescenceEdet J. Ekanem, Charles L. R. Barnard, John M. Ottaway, Gordon S. Fell Behaviour of Zeeman Corrected Atomic Fluorescence at High Source Currents-Guo Tie-Zheng, Roger Stephens Atomisation in Graphite Furnace Atomic Absorption Spectrometry: Atmospheric Pressure vis-a-vis Vacuum Vaporisation-Ralph E. Sturgeon, James S . Arlow Depth Concentration Profiles Obtained by Carbon Furnace Atomic Absorption Spec- trometry for Nickel and Aluminium in Human Skin-John F.Alder, Maria C. C. Batoreu, Anthony D. Pearse, Ronald Marks Determination of Cadmium in Blood Plasma by Graphite Furnace Atomic Absorption Spectrometry-M. M. Black, Gordon S. Fell, John M. Ottaway Direct Determination of Lead in Soils and Sediments by Atomjc Absorption Spec- trometry Employing a Graphite Capsule Flame Atomiser-Janez Stupar Determination of Dissolved Inorganic Selenium (IV) and Selenium(V1) Species in Natural Waters by Hydride Generation Atomic Absorption Spectrometry-S. C. Apte, A. G. Howard Automation of Molecular Emission Cavity Analysis. Determination of Phosphorus- lbrahim H. El-Hag, Alan Townshend Quality Assurance of Analytical Data, with Special Reference t o the Determination of Lead and Cadmium in Biological Samples-Chandrakant B.Pandya, Tushar S. Patel, Gaurang M. Shah, Natubhai G. Sathawara, Veljeebhai G. Patel, Dinesh J. Parikh, Barid Baran Chatterjee An External Quality Assessment Scheme for Trace Elements in Biological Fluids- . Andrew Taylor, R. J. Briggs Blood Cadmium Determination-Results of an External Quality Assessment Scheme Bryan J. Starkey, Andrew Taylor, Arthur W. Walker ATOMIC SPECTROMETRY UPDATE 121R Atomisation and Excitation-Barry L. Sharp, Neil W. Barnett, John C. Burridge and John M. Ottaway 155R References Typeset and printed by Heffers Printers Ltd, Cambridge, EnglandJASPE2 l(5) 313-400,121R-168R (1986) October 1986 Journal of Analytical Atomic Spectrometry Including Atomic Spectrometry Updates CONTENTS NEWS AND VIEWS 313 EditoriaCJ.M. Ottaway 314 3t7 Conference Reports 320 ASU Highlights 321 Book Review 321 321 Conferences and Meetings 324 Papers in Future Issues Atomic Spectrometry Viewpoint-L. Ebdon and R. C. Hutton RSC Awards 1986: Analytical Spectroscopy PAPERS 325 331 337 343 349 355 359 365 369 373 379 383 387 39 1 397 Spatial Emission Characteristics and Excitation Mechanisms in the Inductively Coupled Plasma. A Review-John Davies, Richard D. Snook Multi-element Analysis of Ferrotungsten by Inductively Coupled Plasma Atomic Emission Spectrometry-Ivan H lavate k, I rena H lavatkova Electrothermal Vaporisation Sample Introduction into an Atmospheric Pressure Helium Microwave-induced Plasma for the Determination of Iodine in Hydrochloric Acid- Neil W.Barnett, (the late) Gordon F. Kirkbright Inductively Coupled Plasma Atomic FluorescenCe Spectrometric Determination of Cadmium, Copper, Iron, Lead, Manganese and Zinc-Richard F. Sanzolone Improved Determination of Cadmium in Blood by Flame Atomic FluorescenceEdet J. Ekanem, Charles L. R. Barnard, John M. Ottaway, Gordon S. Fell Behaviour of Zeeman Corrected Atomic Fluorescence at High Source Currents-Guo Tie-Zheng, Roger Stephens Atomisation in Graphite Furnace Atomic Absorption Spectrometry: Atmospheric Pressure vis-a-vis Vacuum Vaporisation-Ralph E. Sturgeon, James S . Arlow Depth Concentration Profiles Obtained by Carbon Furnace Atomic Absorption Spec- trometry for Nickel and Aluminium in Human Skin-John F. Alder, Maria C. C. Batoreu, Anthony D. Pearse, Ronald Marks Determination of Cadmium in Blood Plasma by Graphite Furnace Atomic Absorption Spectrometry-M.M. Black, Gordon S. Fell, John M. Ottaway Direct Determination of Lead in Soils and Sediments by Atomjc Absorption Spec- trometry Employing a Graphite Capsule Flame Atomiser-Janez Stupar Determination of Dissolved Inorganic Selenium (IV) and Selenium(V1) Species in Natural Waters by Hydride Generation Atomic Absorption Spectrometry-S. C. Apte, A. G. Howard Automation of Molecular Emission Cavity Analysis. Determination of Phosphorus- lbrahim H. El-Hag, Alan Townshend Quality Assurance of Analytical Data, with Special Reference t o the Determination of Lead and Cadmium in Biological Samples-Chandrakant B. Pandya, Tushar S. Patel, Gaurang M. Shah, Natubhai G. Sathawara, Veljeebhai G. Patel, Dinesh J. Parikh, Barid Baran Chatterjee An External Quality Assessment Scheme for Trace Elements in Biological Fluids- . Andrew Taylor, R. J. Briggs Blood Cadmium Determination-Results of an External Quality Assessment Scheme Bryan J. Starkey, Andrew Taylor, Arthur W. Walker ATOMIC SPECTROMETRY UPDATE 121R Atomisation and Excitation-Barry L. Sharp, Neil W. Barnett, John C. Burridge and John M. Ottaway 155R References Typeset and printed by Heffers Printers Ltd, Cambridge, England

ISSN:0267-9477    

DOI:10.1039/JA98601BX019

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

V Online access to the world’s 1 chemistry literature lable ... now avail .,,from the Analytical Abstracts ONLINE \ I Analytical Abstracts Online ... is the online equivalent of hard copy Analytical Abstracts, the western world’s most comprehensive abstracting journal dealing solely with analytical chemistry in all i t s aspects. Analytical Abstracts Online ... contains bibliographic information on general, inorganic, organic, biochemical, pharmaceutical, food, agricultural and environmental aspects of analytical chemistry, including computer and instrumentational applications in analysis. Analytical Abstracts Online ... offers: 0 Comprehensive coverage of analytical chemistry 0 Coverage 1980-to date : over 70,000 items 0 Analytical methods in high detail 0 Quality controlled language indexes 0 Easy access via DATA-STAR, (Plaza Suite, 1 14 Jermyn Street, London SW1 Y 6HJ); and PERGAMON INFOLINE Ltd., (1 2 Vandy Street, London EC2A 2DE).For further information contact your chosen host direct or write to:- The Royal Society of Chemistry, The University, Nottingham, NG7 2RD. Tel. 0602 50741 1 Telex: 37488 ROYAL SOCIETY OF CHEMISTRY Information Services11 ANALYTICAL [___I SCIENCES Analytical Sciences is a new international journal which commenced publication in April 1985 dealing with fundamental and applied aspects of analytical chemistry. It is published bimonthly by the Japan Society for Analytical Chemistry and is distributed outside Japan by The Royal Society of Chemistry. All items are in English and although the majority originate from Japanese sources important items from other parts of the world are also included.~ Coverage VOl. 1 N0.1 1985 I Each issue is divided into three sections: Analytical Sciences is an interdisciplinary medium for the dissemination of new ideas in chemical Original Papers describe the original work in full detail. Each issue contains approximately 15-20 papers. analysis. It includes both research articles and application papers covering all the developments in analytical sciences. It also provides an interdisciplinary i n terf ace bet ween chemical, physical, agricultural, pharmaceutical and biochemical sciences. Letters to the Editor are concerned with the opinions of authors working Analytical Sciences also includes review articles and will present brief reports on Annual Meetings including those of The Japan Society for Analytical Chemistry (JSAC), The Annual Symposium of JSAC, and the international joint symposiums sponsored by JSAC.Analytical Sciences reports the results of “Discussion Groups” on special subjects held by the members of JSAC. at the forefront of analytical chemistry. They are intended to provide a brief overview of current and future trends in analytical chemistry. Instrumental Achievements reports on new attainment in instrumentation andlor in measurement. - Editorial and Advisory Boards Editorial Board Editor: Shizuo FUJIWARA Associate Editors: Reinosuke HARA, Rokuro KURODA, Tei i c h i M ATSU M AE, Toshio NAN BARA, Tatsuya SEKINE, Mitsugi SENDA, Yoshinori SUGITAN I, Shin TSUGE. Advisoty Board Hideo AKAIWA, Gunma University Allen J.BARD, Universityof Texas at Austin, TX. Henry FREISER, University of Arizona, Tucson, AZ. Taichiro FUJINAGA, Nara University of Education Gary HORLICK, University of Alberta, Edmonton Hitoshi KAMADA, Tadao KASEI, Japan Analytical In strum en ts Manufacturer’s Association Theodore KUWANA, University of Kansas, l a wrence, KS. Herbert A. LAlTl N EN, University of Florida, Gainesville, FL. Giichi MUTO, Saitama Institute of Technology Ern0 PUNGOR,Technical University Budapest Et ienne ROTH, Nucleaires de Saclay, Padis Jaromir RUZICKA, Technical University of Denmark, Lyngby Nobufusa SAITO, Toho University W. SIMON, ETH-Zentrum, Zurich Gunther TdLG, lnstitut fur Spektrochemie und Angewandte Spektroskopie, Dortmund Keihei UENO, Kumamoto Institute of Technology Fr i t s U M LAN D , Wes tfallische Wilhelm s- Universita t, Mijn s ter Toyozo UNO, Mokogawa Women’s University T.S. WEST, The Macaulay Institute for Soil Research, Aberdeen Yuri A. ZOLOTOV, Vernadskii Institute of Geochemical and Analytical Chemistry, Moscow SubscriDtions Jan-Dec 1986 (6 issues) $ 65.00 for personal use $120.00 for institutional use Jan-Dec 1987 (6 issues) $ 65.00 for personal use $120.00 for institutional use Back issues April-Dec 1985 $ 55.00 for personal use $110.00 for institutional use ISSN: 0910 6340 Issues will be sent air speeded service where these are available Advance payment required. Orders should be sent to: The Royal Society of Chemistry, Journals Subscription Dept., Distribution Centre, Blackhorse Road, Letchworth, Herts, SG6 IHN.United Kingdom ROYAL SOCIETY OF CHEMISTRY lnformat ion Services11 ANALYTICAL [___I SCIENCES Analytical Sciences is a new international journal which commenced publication in April 1985 dealing with fundamental and applied aspects of analytical chemistry. It is published bimonthly by the Japan Society for Analytical Chemistry and is distributed outside Japan by The Royal Society of Chemistry. All items are in English and although the majority originate from Japanese sources important items from other parts of the world are also included. ~ Coverage VOl. 1 N0.1 1985 I Each issue is divided into three sections: Analytical Sciences is an interdisciplinary medium for the dissemination of new ideas in chemical Original Papers describe the original work in full detail.Each issue contains approximately 15-20 papers. analysis. It includes both research articles and application papers covering all the developments in analytical sciences. It also provides an interdisciplinary i n terf ace bet ween chemical, physical, agricultural, pharmaceutical and biochemical sciences. Letters to the Editor are concerned with the opinions of authors working Analytical Sciences also includes review articles and will present brief reports on Annual Meetings including those of The Japan Society for Analytical Chemistry (JSAC), The Annual Symposium of JSAC, and the international joint symposiums sponsored by JSAC. Analytical Sciences reports the results of “Discussion Groups” on special subjects held by the members of JSAC.at the forefront of analytical chemistry. They are intended to provide a brief overview of current and future trends in analytical chemistry. Instrumental Achievements reports on new attainment in instrumentation andlor in measurement. - Editorial and Advisory Boards Editorial Board Editor: Shizuo FUJIWARA Associate Editors: Reinosuke HARA, Rokuro KURODA, Tei i c h i M ATSU M AE, Toshio NAN BARA, Tatsuya SEKINE, Mitsugi SENDA, Yoshinori SUGITAN I, Shin TSUGE. Advisoty Board Hideo AKAIWA, Gunma University Allen J. BARD, Universityof Texas at Austin, TX. Henry FREISER, University of Arizona, Tucson, AZ. Taichiro FUJINAGA, Nara University of Education Gary HORLICK, University of Alberta, Edmonton Hitoshi KAMADA, Tadao KASEI, Japan Analytical In strum en ts Manufacturer’s Association Theodore KUWANA, University of Kansas, l a wrence, KS.Herbert A. LAlTl N EN, University of Florida, Gainesville, FL. Giichi MUTO, Saitama Institute of Technology Ern0 PUNGOR,Technical University Budapest Et ienne ROTH, Nucleaires de Saclay, Padis Jaromir RUZICKA, Technical University of Denmark, Lyngby Nobufusa SAITO, Toho University W. SIMON, ETH-Zentrum, Zurich Gunther TdLG, lnstitut fur Spektrochemie und Angewandte Spektroskopie, Dortmund Keihei UENO, Kumamoto Institute of Technology Fr i t s U M LAN D , Wes tfallische Wilhelm s- Universita t, Mijn s ter Toyozo UNO, Mokogawa Women’s University T. S. WEST, The Macaulay Institute for Soil Research, Aberdeen Yuri A. ZOLOTOV, Vernadskii Institute of Geochemical and Analytical Chemistry, Moscow SubscriDtions Jan-Dec 1986 (6 issues) $ 65.00 for personal use $120.00 for institutional use Jan-Dec 1987 (6 issues) $ 65.00 for personal use $120.00 for institutional use Back issues April-Dec 1985 $ 55.00 for personal use $110.00 for institutional use ISSN: 0910 6340 Issues will be sent air speeded service where these are available Advance payment required.Orders should be sent to: The Royal Society of Chemistry, Journals Subscription Dept., Distribution Centre, Blackhorse Road, Letchworth, Herts, SG6 IHN. United Kingdom ROYAL SOCIETY OF CHEMISTRY lnformat ion Servicesiv JOURNAL OF MICRONUTRIENT AN A LY SI S Editors Robert Macrae, University of Reading, UK Gary R. Beecher, Beltsville, Human Nutrition Centre, Maryland, USA Richard C.Rose, The Pennsylvania State University, Hershey, USA. The Journal of Micronutrient Analysis covers all methods for the detection and determination of micronutrients and their metabolites at a l l stages within the food chain. The term micronutrient is used to describe all minor food components known, or suspected, to have a nutritional role in man and other vertebrates. Topics include: methods intended for animal feeds, raw foodstuffs and clinical samples (blood, urine, tissue, etc.) developments of methods, application to specific areas and the interpretation of the significance of results. evaluation of techniques by comparison with alternative methods. * results of collaborative trials. Results of the application of standard methods of analysis will only be published where the interpretation of the data provides a significant contribution to our knowledge of the levels of micronutrients in important fields where such knowledge i s lacking.Nutritional papersper se will not be accepted. SUBSCRIPTION INFORMATION Volume 3 (1987) 4 issues Price: €65.00 - UK delivery; €72.00/US$119.00 - outside UK delivery. Subscriptions to all countries are airspeeded at no extra cost t o the subscriber. f sterling price is definitive. US$ price can be subject to exchange rate fluctuations. (ISSN: 0266-349X) SEND FOR A FREE SPECIMEN COPY Edited by R.E. Hester University of York The aim of this book is to provide a wide-ranging and authoritative coverage of topics which are fundamental to our understanding and appreciation of the nature of our environment.The six chapters are all written by authors who are acknowledged experts in their particular fields, with the intention of providing a sufficient depth of treament to satisfy the needs of serious students of the subject matter but in a style and level which will be found comprehensible and interesting by the generally concerned, involved, and educated layman. This is not primarily a book for the expert who already is well informed and engaged actively in environmental chemistry, although the broad range of its coverage undoubtedly will have some appeal for such experts. Rather it is aimed at students, at managers in industry, administrators, politicians, legislators, and other people with a concern for the quality of our environment and a need to understand the issues involved in its management. Brief Contents Monitoring By C N Hewitt, University of Lancaster and R M Harrison, University of Essex The Air by A G Clarke, University of Leeds Water by H fish, Natural Environment Research Council Land Contamination and Reclamation By E E Finnecy and K W Pearce, Harwell Laboratory Assessing the Ecological and Health Effects of Pollution by S Smith, King 's College, London Regulation and the Economics of Pollution Control by P Burrows, N Highton, University of York and A I Ogus, University of Newcastle upon Tyne Appendix: Information Retrieval by M L Richardson Hardcover 348pp ISBN 0 85186 907 6 Price f42.50 ($77.00) RSC Members €1 7.50 RSC Members are entitled to a 20% discount on bulk orders of 15 or more copies. Ordering : Non-RSC Members should send their orders to: The Royal Society of Chemistry, Distribution Centre, Blackhorse Road, Letchworth, Herts SG6 1 HN, UK. RSC Members should send their orders to: The Royal Society of Chemistry, Membership Manager, 30 Russell Square, London WCl B 5DT, UK. ROYAL SOCIETY OF CHEMISTRY Information ervices

ISSN:0267-9477    

DOI:10.1039/JA98601FP033

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

... Vlll ~ ~ Following publication of Annual Reports on Analytical Atomic Spectroscopy Vol. 14, this series will be discontinued. Much of the material covered, however, will appear in journal of Analytical Atomic Spectrometry OMS) under the heading Atomic Spectrometry Updates. ANNUAL REPORTS Annual Reports M Analytical Atomic Spectroscopy Vdums 14 Hardcover 460pp ISBN 0 85186 677 8 Price $65.00 ($1 17.00) Still available: Vol. 3 (1973) 0 85186 253 6 212.00 ($22.00) Vol. 4 (1914) 0 85186 254 4 217.00 ($30.00) Vol. 5 (1975) 0 85186 751 X $20.00 ($36.00) Vol. 6 (1916) 0 85186 747 2 226.00 ($41.00) Vol. 1 (1977) 0 85186 731 5 525.00 ($45.00) Vol. 8 (1918) 0 85186 630 1 225.00 ($45.00) Vol. 9 (1979) 0 85186 727 8 237.00 ($66.00) Vol. 10 (1980) 0 85186 717 0 239.00 ($70.00) Vol.11 (1981) 0 85186 701 3 E53.00 ($95.00) Vol. 12 (1982) 0 85186 697 2 E45.00 ($81.00) Vol. 13 (1983) 0 85186 687 5 255.00 ($99.00) Special Package Price (Vols 3-14) 2282.00 ($508.00) Ordering: Orders should be sent to The Royal Society of Chemistry, Distribution Centre, Blackhorse Road, Letchworth, Herts. SG6 lHN, U.K. Non-RSC member prices quoted. RSC members are entitled ro a discounr on most publications. Derails available from: Assisrant Membership Officer, The Royal Society of Chemistry, 30 Russell Square, London WClB 5DT, U.K. US$ prices quoted. ROYAL Information Services ON ANALYTICAL ATOMIC SPECTROSCOPY VOL 14. Edited by L Ebdon, Plymouth Polytechnic and M S Cresser, University of Aberdeen This publication reports on current developments in all branches of analytical atomic emission, absorption and fluorescence spectroscopy with reference to papers published and lectures presented during 1984.Much of the information is presented in tabular form for ease of reference. Brief Contents: ATOMIZATION AND EXCITATION: Arcs, Sparks, Lasers and Low-Pressure Discharges; Plasmas; Flames; Elect ro t her ma1 Atomization; Vapour Generation. INSTRUMENTATION: Light Sources; Optical Systems and Detectors; Background Correction; Automatic Sample Introduction; Instrument Control and Data Processing; Complete Instruments; Commercial Instruments. METHODOLOGY: New Methods; Detection Limits, Precision and Accuracy; Standards and Standardization. APPLICATIONS: Chemicals; Metals; Refractories and Metal Oxides, Ceramics, Slags and Cements; Minerals; Air; Water; Sods, Plants and Fertilizers; Foods and Beverages; Body Tissues and Fluids.REFERENCES AUTHOR INDEX SUBJECT INDEX ‘I. . . , an essential reference work for atomic spectroscopists and for chemists concerned with trace metal analysis.” - J E Page, Chemistry and Industry, reviewing Vole 11... Vlll ~ ~ Following publication of Annual Reports on Analytical Atomic Spectroscopy Vol. 14, this series will be discontinued. Much of the material covered, however, will appear in journal of Analytical Atomic Spectrometry OMS) under the heading Atomic Spectrometry Updates. ANNUAL REPORTS Annual Reports M Analytical Atomic Spectroscopy Vdums 14 Hardcover 460pp ISBN 0 85186 677 8 Price $65.00 ($1 17.00) Still available: Vol. 3 (1973) 0 85186 253 6 212.00 ($22.00) Vol. 4 (1914) 0 85186 254 4 217.00 ($30.00) Vol.5 (1975) 0 85186 751 X $20.00 ($36.00) Vol. 6 (1916) 0 85186 747 2 226.00 ($41.00) Vol. 1 (1977) 0 85186 731 5 525.00 ($45.00) Vol. 8 (1918) 0 85186 630 1 225.00 ($45.00) Vol. 9 (1979) 0 85186 727 8 237.00 ($66.00) Vol. 10 (1980) 0 85186 717 0 239.00 ($70.00) Vol. 11 (1981) 0 85186 701 3 E53.00 ($95.00) Vol. 12 (1982) 0 85186 697 2 E45.00 ($81.00) Vol. 13 (1983) 0 85186 687 5 255.00 ($99.00) Special Package Price (Vols 3-14) 2282.00 ($508.00) Ordering: Orders should be sent to The Royal Society of Chemistry, Distribution Centre, Blackhorse Road, Letchworth, Herts. SG6 lHN, U.K. Non-RSC member prices quoted. RSC members are entitled ro a discounr on most publications. Derails available from: Assisrant Membership Officer, The Royal Society of Chemistry, 30 Russell Square, London WClB 5DT, U.K.US$ prices quoted. ROYAL Information Services ON ANALYTICAL ATOMIC SPECTROSCOPY VOL 14. Edited by L Ebdon, Plymouth Polytechnic and M S Cresser, University of Aberdeen This publication reports on current developments in all branches of analytical atomic emission, absorption and fluorescence spectroscopy with reference to papers published and lectures presented during 1984. Much of the information is presented in tabular form for ease of reference. Brief Contents: ATOMIZATION AND EXCITATION: Arcs, Sparks, Lasers and Low-Pressure Discharges; Plasmas; Flames; Elect ro t her ma1 Atomization; Vapour Generation. INSTRUMENTATION: Light Sources; Optical Systems and Detectors; Background Correction; Automatic Sample Introduction; Instrument Control and Data Processing; Complete Instruments; Commercial Instruments.METHODOLOGY: New Methods; Detection Limits, Precision and Accuracy; Standards and Standardization. APPLICATIONS: Chemicals; Metals; Refractories and Metal Oxides, Ceramics, Slags and Cements; Minerals; Air; Water; Sods, Plants and Fertilizers; Foods and Beverages; Body Tissues and Fluids. REFERENCES AUTHOR INDEX SUBJECT INDEX ‘I. . . , an essential reference work for atomic spectroscopists and for chemists concerned with trace metal analysis.” - J E Page, Chemistry and Industry, reviewing Vole 11... Vlll ~ ~ Following publication of Annual Reports on Analytical Atomic Spectroscopy Vol. 14, this series will be discontinued.Much of the material covered, however, will appear in journal of Analytical Atomic Spectrometry OMS) under the heading Atomic Spectrometry Updates. ANNUAL REPORTS Annual Reports M Analytical Atomic Spectroscopy Vdums 14 Hardcover 460pp ISBN 0 85186 677 8 Price $65.00 ($1 17.00) Still available: Vol. 3 (1973) 0 85186 253 6 212.00 ($22.00) Vol. 4 (1914) 0 85186 254 4 217.00 ($30.00) Vol. 5 (1975) 0 85186 751 X $20.00 ($36.00) Vol. 6 (1916) 0 85186 747 2 226.00 ($41.00) Vol. 1 (1977) 0 85186 731 5 525.00 ($45.00) Vol. 8 (1918) 0 85186 630 1 225.00 ($45.00) Vol. 9 (1979) 0 85186 727 8 237.00 ($66.00) Vol. 10 (1980) 0 85186 717 0 239.00 ($70.00) Vol. 11 (1981) 0 85186 701 3 E53.00 ($95.00) Vol. 12 (1982) 0 85186 697 2 E45.00 ($81.00) Vol. 13 (1983) 0 85186 687 5 255.00 ($99.00) Special Package Price (Vols 3-14) 2282.00 ($508.00) Ordering: Orders should be sent to The Royal Society of Chemistry, Distribution Centre, Blackhorse Road, Letchworth, Herts.SG6 lHN, U.K. Non-RSC member prices quoted. RSC members are entitled ro a discounr on most publications. Derails available from: Assisrant Membership Officer, The Royal Society of Chemistry, 30 Russell Square, London WClB 5DT, U.K. US$ prices quoted. ROYAL Information Services ON ANALYTICAL ATOMIC SPECTROSCOPY VOL 14. Edited by L Ebdon, Plymouth Polytechnic and M S Cresser, University of Aberdeen This publication reports on current developments in all branches of analytical atomic emission, absorption and fluorescence spectroscopy with reference to papers published and lectures presented during 1984.Much of the information is presented in tabular form for ease of reference. Brief Contents: ATOMIZATION AND EXCITATION: Arcs, Sparks, Lasers and Low-Pressure Discharges; Plasmas; Flames; Elect ro t her ma1 Atomization; Vapour Generation. INSTRUMENTATION: Light Sources; Optical Systems and Detectors; Background Correction; Automatic Sample Introduction; Instrument Control and Data Processing; Complete Instruments; Commercial Instruments. METHODOLOGY: New Methods; Detection Limits, Precision and Accuracy; Standards and Standardization. APPLICATIONS: Chemicals; Metals; Refractories and Metal Oxides, Ceramics, Slags and Cements; Minerals; Air; Water; Sods, Plants and Fertilizers; Foods and Beverages; Body Tissues and Fluids. REFERENCES AUTHOR INDEX SUBJECT INDEX ‘I.. . , an essential reference work for atomic spectroscopists and for chemists concerned with trace metal analysis.” - J E Page, Chemistry and Industry, reviewing Vole 11... Vlll ~ ~ Following publication of Annual Reports on Analytical Atomic Spectroscopy Vol. 14, this series will be discontinued. Much of the material covered, however, will appear in journal of Analytical Atomic Spectrometry OMS) under the heading Atomic Spectrometry Updates. ANNUAL REPORTS Annual Reports M Analytical Atomic Spectroscopy Vdums 14 Hardcover 460pp ISBN 0 85186 677 8 Price $65.00 ($1 17.00) Still available: Vol. 3 (1973) 0 85186 253 6 212.00 ($22.00) Vol. 4 (1914) 0 85186 254 4 217.00 ($30.00) Vol. 5 (1975) 0 85186 751 X $20.00 ($36.00) Vol. 6 (1916) 0 85186 747 2 226.00 ($41.00) Vol.1 (1977) 0 85186 731 5 525.00 ($45.00) Vol. 8 (1918) 0 85186 630 1 225.00 ($45.00) Vol. 9 (1979) 0 85186 727 8 237.00 ($66.00) Vol. 10 (1980) 0 85186 717 0 239.00 ($70.00) Vol. 11 (1981) 0 85186 701 3 E53.00 ($95.00) Vol. 12 (1982) 0 85186 697 2 E45.00 ($81.00) Vol. 13 (1983) 0 85186 687 5 255.00 ($99.00) Special Package Price (Vols 3-14) 2282.00 ($508.00) Ordering: Orders should be sent to The Royal Society of Chemistry, Distribution Centre, Blackhorse Road, Letchworth, Herts. SG6 lHN, U.K. Non-RSC member prices quoted. RSC members are entitled ro a discounr on most publications. Derails available from: Assisrant Membership Officer, The Royal Society of Chemistry, 30 Russell Square, London WClB 5DT, U.K. US$ prices quoted. ROYAL Information Services ON ANALYTICAL ATOMIC SPECTROSCOPY VOL 14.Edited by L Ebdon, Plymouth Polytechnic and M S Cresser, University of Aberdeen This publication reports on current developments in all branches of analytical atomic emission, absorption and fluorescence spectroscopy with reference to papers published and lectures presented during 1984. Much of the information is presented in tabular form for ease of reference. Brief Contents: ATOMIZATION AND EXCITATION: Arcs, Sparks, Lasers and Low-Pressure Discharges; Plasmas; Flames; Elect ro t her ma1 Atomization; Vapour Generation. INSTRUMENTATION: Light Sources; Optical Systems and Detectors; Background Correction; Automatic Sample Introduction; Instrument Control and Data Processing; Complete Instruments; Commercial Instruments. METHODOLOGY: New Methods; Detection Limits, Precision and Accuracy; Standards and Standardization. APPLICATIONS: Chemicals; Metals; Refractories and Metal Oxides, Ceramics, Slags and Cements; Minerals; Air; Water; Sods, Plants and Fertilizers; Foods and Beverages; Body Tissues and Fluids. REFERENCES AUTHOR INDEX SUBJECT INDEX ‘I. . . , an essential reference work for atomic spectroscopists and for chemists concerned with trace metal analysis.” - J E Page, Chemistry and Industry, reviewing Vole 11

ISSN:0267-9477    

DOI:10.1039/JA98601BP037

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 121R ATOMIC SPECTROMETRY UPDATE-ATOMISATION AND EXCITATION Barry L. Sharp* Macaula y Institute for Soil Research, Craigiebuckler, Aberdeen A69 2QJ, UK Neil W. Barnett Department of Environmental Sciences, Plymouth Polytechnic, Drake Circus, Plymouth PL4 8AA, UK John C. Burridge Macaulay Institute for Soil Research, Craigiebuckler, Aberdeen A69 ZQJ, UK John M. Ottaway Department of Pure and Applied Chemistry, University of Strathclyde, Cathedral Street, Glasgow GI IXL, UK Summary of Contents 1 Arcs, Sparks, Lasers and Low-pressure Discharges 1.1. Arcs 1.2. Sparks 1.3. Lasers I .4. Low-pressure Discharges 1.4.1. Glow-discharge lamps 1.4.2. Hollow-cathode discharges 1.4.3. Other sources 2 Plasmas 2.1. Inductively Coupled Plasmas 2.1 .I.Plasma characteristics 2.1.2. Sample introduction 2.1.3. Flow injection and chromatography 2.1.4. Chemometrics 2.1.5. Inductively coupled plasma mass spectrometry (ICP-MS) 2.1.6. Inductively coupled plasma atomic fluorescence spectrometry (ICP-AFS) 2.1.7. Instrumentation 2.2. Microwave-excited Plasmas 2.2.1. Fundamental studies 2.2.2. Instrumentation 2.2.3. Chromatography 2.3. Direct Current Plasmas 2.3.1. Fundamental studies 2.3.2. Instrumentation 3 Flames 3.1. 3.2. 3.3. 3.4. 3.5. 3.6. Fundamental Studies Interference Studies Instrumentation C hem omet rics Sample Introduction 3.5.1. Nebulisers and spray chambers 3.5.2. Atom-tra p pi ng techniques 3.5.3. Flow injection techniques 3.5.4. Sample introduction by volatilisation 3.5.5. Chromatographic detection Applications of Lasers 3.6.1.Laser-excited atomic fluorescence spectrometry (LAFS) 3.6.2. Laser-enhanced ionisation (LEI) 3.6.3. Other studies 4 Electrothermal Atomisation 4.1. Atomiser Design 4.2. Atomisation Surface 4.3. Sample Introduction 4.4. Fundamental Processes 4.5. Interference Studies 4.6. Developments in Technique 5 Chemical Vapour Generation 5.1. Hydride Generation 5.2. Mercury Determination * Review Topic Co-ordinator, to whom correspondence should be addressed.122R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 This review describes developments in atomisation and excitation in analytical atomic spectrometry. It is based upon publications and conference reports received during the period from 1st January 1985 to 28th February 1986 and follows chronologically Chapter 1 in Volume 14 of the Annual Reports on Analytical Atomic Spectroscopy.The 14-month review period results from the change from book to journal format but subsequent reviews will appear on an annual cycle. The format is similar to that used in ARAASwith sections devoted to arcs, sparks, lasers and low-pressure discharges, plasmas, flames, electrothermal vaporisation and chemical vapour generation. Only reports of new developments related to atomisation and excitation are included in this review, applications of established techniques are reported in Updates devoted to specific applications areas. The references cited, prefixed by S/, or for conference reports, SIC, may be found in the supplement distributed to subscribers of JAAS.A key to the location of individual references within JAAS is given at the end of the review. The authors would welcome readers' comments or suggestions and these should be addressed to the Review Topic Co-ordinator. 1. ARCS, SPARKS, LASERS AND LOW-PRESSURE DISCHARGES 1.1. Arcs Every year numerous reports appear in which various factors affecting the performance of specific arc procedures are described. Arc methods for AES have now been widely used for so long that most of these reports cannot contain findings that are entirely original or capable of being integrated into new conclusions of general value. Nevertheless, it is reassur- ing that so many analysts appreciate the importance of arc methods for the analysis of solid samples, especially for trace elements. The determination of Ru in tungsten, after conver- sion into its oxide (86/1043) and of Au in rocks (86/416) are typical recent examples.Novel source configurations were conspicuous by their absence this review period! Effects related to the gas used for the arc atmosphere were a common topic of interest with fairly standard studies on sensitivity (861C698) and on the stability achieved by gas sheathing (86/C268). How did the early spectrochemists manage without Ar? Techniques suitable for analysing radioactive materials were described by Faires et al. (S/664) and by Nickel (S/C1153). Automated microdensitometry appears to be receiving less attention than it deserves, only one report being noted (S/C1133), in which a wavelength measurement precision of k0.004 nm in the range 250-350 nm was claimed.Element identification was on the basis of a look-up table of wavelengths. The determination of gases in metals and alloys by arc methods is seldom reported. A recently described procedure for N and 0 in steels by means of a 40-A d.c. arc should therefore revive interest in the technique (86/C571). Contents in the range from 0.005 to ca. 2% were measured using the N 821.60- and 0 777.19-nm lines and adjacent Ar lines for internal standardisation. The predominant influence of sample composition on arc analysis is reflected in the high proportion of reports that deal with matrix effects, carriers or buffers, generally in the context of a specific analytical procedure. Nearly a third of all the arc reports reviewed have been concerned with this topic.Some of these did little more than demonstrate the effectiveness of a particular buffer or carrier, for instance when using KC1 plus LiF for the determination of rare earths in uranium com- pounds (S/80), LiF plus Li2C03 for 17 trace impurities in molybdenum (9230) or Ga203 for Be, Bi, Ga and Ge in petroleum (861C629). More interesting are those reports in which comparisons are made among a set of different compounds. These are usually inorganic, such as LiF, Li2C03, Li2B407, NaCl and CuCl, which were studied by Florian and Zimmer (86/C300), and NaCl, NaF, CaF2, CdF2, PbF2, Ga203 and AgCl used by Guirguis et al. (86/C565), but suites of organic carriers have attracted attention once more, as is shown by the work of Turker and Dogan (86/C569, 86/1359, 86/1360). The reviewer does not anticipate that the obser- vations reported will do very much to persuade other analysts to modify their own, already established carrier - buffer cock- tails! There is a tendency to explain most effects of buffers and carriers as arising from changes in excitation temperature, electron number density and sample volatilisation.However, reports in this review period serve as a timely reminder that diffusion processes (S/32, S/62, 86/124, 86/257), which affect analyte retention in the arc plasma, and thermochemical reactions in the sample electrode (86/C573, 86/1080), which affect analyte entry into the plasma, both have a major effect on emission intensities. The material from which the elec- trodes are made also has a significant effect on emission intensity, through physical and chemical processes (S/29, 86/C282, 86/C283).Some method of analyte pre-concentration is often adopted when arc methods are used for trace analysis. Separation of the matrix by evaporation is sometimes possible, and this method was adopted to determine trace elements in cadmium, mercury and tellurium by heating at 600-900°C in the presence of powdered graphite (S/1113), in tin after its conversion into SnBr, (S/173) and in germanium (S/39). In the last example, the Ge samples were placed directly in graphite electrodes and heated in an autoclave at 220 "C for 6 h with 1 + 3 HN03 + HCl. Selective extraction, coprecipitation, elec- trolysis and cation exchange were also applied (S/853, S/1116, 86038, 86/C591, 86/1376).A fire assay pre-concentration by lead with incomplete cupellation, giving detection limits of lO-7-lO-6% for several noble metals in ores and their beneficiation products, illustrates just how sensitive some arc procedures can be (S1135). The properties and uses of arc plasmas are considered in more detail elsewhere in this review (see section 2.3) and only brief comments on their production are made here. The basic problem is how best to entrain a sample in the plasma and to increase its residence time there. Brute force can be applied, as in the determination of Au in geological samples by means of a double-jet 100-A plasmatron with the direct injection of powdered material, a method used by Saichenko et af.(S/1222). The high temperature of 15000 K attainable in this type of device when He is used for plasma production also facilitates the determination of non-metals such as B, C1, F, P, N and S (861C494). Alternatively, a tangential Ar flow can be used to rotate the arc plasma around an orifice in the anode disk through which the aerosol is introduced (S/803). Scaling up the power generally used with DCPs by placing two or three pairs of arc electrodes in parallel around the aerosol- flow axis, with close similarities to ICP configurations, is yet another approach that has recently been advocated by Piepmeier et al. (S/C258, 86/C1214). All of these d.c. arc techniques have some merits, but they still remain unlikely to become as widely adopted as the ICP. 1.2. Sparks Recent reports concerning source configurations and analy- tical procedures have not disclosed any exciting new develop- ments or ingenious devices that would merit detailed com- ment.Two laboratories reported the construction of their own direct reading spectrometers, in one instance converting a spectrograph into a two-channel instrument for C in steel (86/418) and in the other, constructing a spectrometer toJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986. VOL. 1 123R determine traces of Cu, Fe and Si in high-purity aluminium (S/229). In the latter report, some emphasis was placed on the need to reduce stray light within the instrument, hardly a surprise to established instrument manufacturers. A compari- son of fused silica and silicone polymer clad fibre optic light guides by Ono grid Saeki (86/370) showed that a clad bundle guide with wide aperture and large core area could be used to transmit spark radiation at wavelengths above 268 nm for a distance of more than 10 m.Light losses were serious at shorter wavelengths, e.g., for C, P and S. Microspark analysis is again attracting attention as a consequence of developments in solid-state technology (86/C813), which have enabled Ca, K and Na to be determined using the emission generated by a single mini-spark from small samples of renal fluid (86/C854). The use of rotrodes (S/657,86/226), effects of gas flow on the transfer of sample material to the counter electrode (86/C567) and a significant matrix effect of Al on the determination of trace elements in zinc cast alloys (86/C612), are only of limited interest.The conclusion reached by Jimenez-Seco et al. (86/C620) that a single calibration curve can be used to determine C and Ni over an extensive range of steel and cast iron types is of much wider interest. Over 100 standards from various sources were included in the study. The influence of surface structures on the spark analysis of metal samples, together with the fact that such structures are highly dependent on local foundry practice, have led to a situation in which the general principles for reducing the effects are well known, but the specific practical remedies adopted need to be evaluated locally. Consequently, every year examples of such evaluations are reported. Thus in this review period, a high-energy pre-spark was used to overcome carbide, oxide or sulphide effects in steel analysis (S/37, S/67, S/215), and to produce a homogeneous microcrystalline structure in Mg alloys (86/C613).A potentially more general way to improve the analysis of low-alloy steels, reported in considerable detail by Strasheim and co-workers (SIC1 181, 86/1391), makes use of a milled depression (called a dimple by the authors) in the flat sample. Among the advantages claimed for Mn determinations using the dimple technique were a shorter pre-spark time, the use of the same calibration curve for forged and cast samples and an improved reproducibility for consecutive exposures. This last feature is important if internal standardisation using a line pair is to be used with a sequential spectrometer.It will be interesting to see whether the dimple technique becomes widely adopted. Few investigations reported in the period covered by this review will lead towards a better understanding of general source characteristics. Further aspects of instability in a voltage-thresholded spark have been reported. The finding that “the mean number of spark firings per power line half-cycle is closer to a half-integer increment of the golden mean than it is to a half-integer” does not yet appear to have analytical applications (S/718). The use of a light scattering technique by Lovik and Scheeline (86/C826) to study particu- late material ejected from an Al-cathode is certainly easier to grasp. A mean particle size of 4.5 pm and velocities in the range from 0.01 to 10 m s-1 were observed. In other work with an A1 spark discharge, the relative times of appearance of A1 atom and ion lines were related to changes of source inductance and capacitance (86/15).Increasing capacitance was found to shorten the duration of emission from highly ionised atoms. At a more practical level, Ar - 5% O2 and Ar saturated with water vapour were evaluated as plasma gases for rare earth determinations (S/78), and the relation between the Fe I1 to Fe I line intensity ratio and the amount of material evaporated by a rectified spark was investigated (86lC284). The application of time-resolved techniques in routine analysis is slowly becoming more widespread. Those noted this review period, however, have been concerned almost exclusively with one problem, that of determining different forms of A1 in steel.The development of pulse distribution analysis (PDA) for this has been briefly reviewed by Ono (86/403), in Japanese with only six references. Two other much fuller reports, by Wittman and Willay (S/869, 86/963), have also discussed the PDA method, as well as the alternative, which uses intensity - time information. The latter method is simpler to apply than PDA and has attracted patent applications (S/148, S/149). The PDA method was also used to evaluate the spark excitation of samples deposited on the end of a graphite electrode (S/137). Most of the useful signal was produced from less than 100 sparks. Electronic integration for a selected period after gap breakdown was found to improve the Cu detection limit by 20-fold when compared with photographic recording.The ultimate detection limit of 1.2 pg was imposed by photon and detector noise. 1.3. Lasers In this section of the review, a few of the more interesting applications and some of the fundamental plasma studies are discussed. Research on topics such as laser enhanced ionisa- tion and fluorescence are considered in more detail in another part of the review (see section 3.6). A significant review of the use of lasers for sample atomisation in AAS, AES, AFS and MS, by Laqua (861366) with 73 references, appeared this year. Procedures for localised and surface analysis, for depth profiling and bulk analysis were all discussed. The general long-established point was made elsewhere (S/C316) that when laser-ablated material is cross-excited with a spark, as in the analysis of dried serum (86/C451), enhanced spectra are obtained. Coupling with a d x .arc to determine trace impurities in periclase insulators is a further typical example of the combination of laser micro- probe sampling with a more powerful excitation source (S/73). However, emission from the laser-generated plasma is itself often sufficiently intense and applications for the determination of C, Mn, P, S and Si in molten pig iron (86/57) and the distribution of B in silicon wafers (86/C587) were noted. The very small area sampled by a normally focused microprobe is sometimes a disadvantage, for instance when the average composition of a large inhomogeneous area is required. Using a cylindrical lens to produce a linear laser- probe footprint, ca.0.1 mm wide by 4-8 mm long, on a filter disc rotated about its axis, a good sensitivity for monitoring Be particles in air was attained by Cremers and Radziemski (86/213). The detection limit was ca. 4 ng of Be on the exposed filter. A continuous optical discharge generated by focusing a 45-W CW COz laser beam in Xe gas at 1150-3200Torr appears to have promise as a tool for gas analysis (86/101). The high electron density of 1017 cm-3, however, may cause unwanted line broadening. Other topics were noted, viz. a new design was claimed to give sharp emission lines without cross- excitation (S/C354), the analytical advantages arising from the high resolution of kchelle spectrometers (S/C723, S/C724) and the effects of external pressure on the plume (S/821), but these do not call for expanded comment at this time.Studies of laser microprobe plasma properties have not been extensive during the past year although the possibilities for improving analytical results, especially for trace elements, depends on such fundamental work (VC314). Stark broaden- ing remains the favoured technique for electron density measurements (S/1090, 86/120). More interesting was a comparison of excitation temperatures measured by means of either a floating double probe (FDP) or by conventional optical intensity (01) Boltzmann plots, reported by Radziem- ski et al. (86/120). In an air plasma induced by a C02 laser operating at 0.5 J per pulse, FDP temperatures ranged from 175000 K at 5 ps to less than 10000 K at 25 ps, while the 0 1 values ranged from 19 000 K at 1 ps to 11 000 K at 25 ps.These results were interpreted as evidence for a convergence to LTE after 25 us. The spatial distribution of sodium dimers, in the124R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 plume vaporised from a polished crystal of Nao.7W03 by a Nd : YAG laser (1060 nm, 120 mJ, 10 ns, 0.04 crnz), was interpreted by Huie and Yeung (86/1398) as clear evidence that sputtering was the main mechanism through which free Na atoms were formed under the particular experimental conditions used. The part that atomic clusters play in atomisation processes still needs further elucidation. 1.4. Low-pressure Discharges 1.4.1. Glow-discharge lamps The design of glow-discharge lamps continues to receive attention (86/729) and the performance of a previously described demountable lamp has again been discussed (86/ C625), with claims of improved detection limits (ca.5 vg g-l for Cr in aluminium) and smoother sputtering. The develop- ment by De Gregorio and Savastano (861C626) of a water- cooled sample support, with integral vacuum channels, represents a significant advance in the analysis of very thin metalsheets, down to 0.1 mm thick. The distortion of such thin films, by heat and also by the expansion of air trapped behind the metal sheet when evacuating the GDL, leading to a short circuit of the cathode and anode, was the problem that had to be overcome. The quantitative analysis of a 1-10 nm thick passivation layer of Cr on 0.15-0.30 mm thick tinplate clearly demonstrated the effectiveness of this new support. Voltage modulation (S/123, S/220, 86/C621) and coupling to a micro- wave cavity (86/C624) continue to be reported as beneficial.The direct attachment of a Grimm type GDL, with an LiF window, to the entrance slit of a vacuum spectrometer allowed the simultaneous determination of 18 elements in nickel-base alloys (S/C1196). This arrangement gave results by AES that compared very favourably with those obtained by XRF. The AES technique had the advantage of a better sensitivity for C, P and S. Only a few reports concerning fundamental plasma processes were noted this year. The effects of the fill gases Ar, N2 and Ne on the emission intensity of Ag, Al, Cu, Sn and Zn lines confirmed the already well known important role that gas composition and energy levels have in ionising and exciting analyte atoms (86/1100).Evidence for charge exchange between inert gas ions and sputtered atoms was obtained by Steers (86lC623) using brass cathodes with Ar, He or Ne as the fill gas. This finding was based on the relative intensities of Cu I and Cu I1 lines having upper energy levels ranging from 5.52 to 16.88 eV. In a study by Pate1 and Winefordner (86/C913), the presence of Cu2, CuO and Pb2 species was established by identifying molecular bands emitted as a result of laser-excited fluorescence. A number of practical problems have come to light as GDLs become more widely used as ion sources for mass spec- trometry, and some of these problems have been discussed at recent conferences. One that may well prove to be the most difficult to solve arises from the very high sensitivity of GDL-MS systems, namely the lack of useful reference standards in the sub-p.p.m.range (S/C437, 86/C1253). For this reason, the analysis of ultra-high purity solids for “tramp” elements is likely to remain semi-quantitative for some while. The extraction of ions from the plasma is critical for the operation of GDL-MS systems. A careful design of this interface by Jakubowski and Stuwer (86/C537) enabled the flux of interfering molecular ions to be reduced by four orders of magnitude, at the same time as increasing the flux of analyte ions by more than two orders of magnitude. The system was fast enough to sample the whole mass range, with ten readings per mass unit, in less than 1 min.A different problem, the over-production of analyte ions in the GDL when laser ablation is used, leading to an increase in noise spikes due to arcing, has been overcome by ablating material from an area adjacent to, rather than within the actual region of the glow discharge (86/C893). Although the analytical application of GDLs has been slower than was anticipated when the Grimm lamp first became commercially available, there is a steady trickle of research reports reflecting the continued interest in this source for routine use. For example, its sensitivity and good SNR have been cited as making it a suitable replacement for AES and XRF spectrometers in foundry laboratories (86/C866, 86/C993). However, De Gregorio et al.(86/C130) showed that a spark pulse discharge analysis technique was capable of giving depth profile information comparable to that from a GDL. The stability of GDLs when solid-metal cathodes are used is one of the main virtues of the source. Non-conducting materials can reduce this, and an electron microprobe has been used to investigate source stability during the analysis of archeological glass samples (86/C293). Two particularly interesting papers were noted that will do more to extend the frontiers of GDL application than will those cited above. In the first report, a detailed study of the emission intensity of Ar I and analyte lines and of sample sputtering rates, in relation to current, voltage, time and matrix composition was described by Bengston (86/98).This permitted an empirical intensity expression to be derived allowing elemental concentrations in copper-based alloys to be determined from a calibration with a single steel reference sample as standard. The procedure was also applied to the determination of A1 in the Zn coating of galvanised steel, and excellent agreement with AAS results was obtained. In the other report, Fraser and Turney (8611333) discussed the performance of a GDL developed as a multigas analyser for respiratory gas analysis. When set up with a short gas-sample line, a 0-9070 response time of 100 ms was achieved for C02, He, N2, N 2 0 and O2 with flow-rates of <20 ml min-1. Good agreement with a long sample line mass spectrometer was found. The differences for inspiratory and expiratory O2 and CO were <2%, while derived variables such as C 0 2 produc- tion differed by ~ 5 % .1.4.2. Hollow-cathode discharges A typical range of reports has appeared over the review period that concern the construction and operation modes of HCLs. These studies have not produced any new results that are likely to have a major impact on the general use of this type of discharge. The coupling of microwave energy to these dis- charges has been reviewed by Caroli et al. (86/1307), with 18 references, and this technique has been advocated on the grounds that analyte emission intensity and SNR are both enhanced (86/C129,86/1362). Improved performance has also been achieved by such well-known methods as pulsing the discharge and using a synchronised, gated detector (S/27), or by the inclusion of CdC12 (S/72). Some unusual cathode geometries have also been investigated (86/C285, 86/C286). Cathode temperature is a significant parameter affecting the analytical use of HCLs as emission sources.On the one hand Vamos-Szilvassy and Buzasi-Gyorfi (86/240) examined the effects of water cooling the cathode, and on the other hand, temperatures high enough to melt nickel-base superalloys, using powers up to 300 W, were successfully exploited by Lowe (86/194) to determine volatile trace impurities. The very small amount of material sometimes available for the analysis of biological samples, perhaps a single drop of blood or a microgram liver biopsy, creates problems that can be over- come by miniaturisation of the discharge (86/C137, 86/853).It is surprising that one interesting configuration, known as the hollow-cathode plume, is not yet being more widely investigated. All the reports noted this year are by one group of researchers, namely Harrison, King and Marcus (861259, 86/C622, 86/C810, 86/C814, 86/C856). In this configuration, a pressure differential forces the discharge through a small axial channel in the HCL base. The emergent plume is a source of intense emission from material sputtered from the innerJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 125R surface of the axial orifice, and because the higher energy region of the plasma is close to the orifice, there is little transport loss of atomised material. Work has been initiated to characterise the plume plasma and to assess its potential as a source of ions for MS. Excitation temperature is a perennial topic, but the one report noted this year, by Zyrnicki and Poslednik (86/264) is of more interest than usual because nine different thermometric species were used, namely A1 11, Ar I, Ar 11, Cu I, Mg I, Mg 11, Pb I, Ti I and Ti I1 lines.It was observed that values derived from atom lines did not vary much from element to element (except for Cu), but that temperatures derived from ion lines increased with the ionisation potential of the element. The values found were 9200 K (Ti 11, 6.82 eV), 13200 K (Mg 11, 7.64 eV) and 24000 K (Ar 11, 15.76 eV), which are a further confirmation of the lack of LTE in such low-pressure discharges. Other plasma parameters in HCLs were discussed at a Hungarian conference (86/C287).1.4.3. Other sources A variety of topics that could not be included under the preceding headings, have been brought together for brief comments in the final section of this part of the review. Although they are specialised and are being studied by relatively few research workers, the reviewer felt that they all have some features that would be of general interest. Although the electrical vaporisation of thin metal films has been studied for a long while by Sacks and co-workers (see also A R A A S , 1983, 13, ref. 1315), there is still no sign of the technique being adopted for routine analysis. Two potential applications have been described recently, one using gold films to determine trace metals in highly acidic matrices (S/637), the other using membrane filters pre-coated with silver to determine atmospheric particulate Pb (91 104).For this latter application, an electrode configuration consisting of a graphite ring in contact with the silver film and an axial, pointed rod in eontact with the lower surface of the filter, was tested (86/1397). Particle-size effects were smaller than with a linear geometry, but poorer detection limits were found. Loading film surfaces with Li2S04 or NH4N03 appeared to inhibit analyte vaporisation and reduce line intensities (86/ 736). Attempts have also been made to improve analytical performance by confining the vaporised-film plasma with a magnetic field. Theta and zeta pinch effects have both been studied. When the vaporisation current was simultaneously used to provide a theta pinch (S/C779), considerable improve- ments in energy coupling were obtained by preventing current oscillations (86/C820). Axial currents through a cylindrical film, the zeta pinch configuration, produced intense back- ground radiation, which prevented the sensitive detection of analyte lines (85/C819,86/C859), Substantial improvements in coupling energy to the plasma with a theta pinch were obtained by Scheeline and Kamla (S/C372) when a single-turn coil of copper, 25 mm thick and carrying a peak current of 60 kA, was replaced by a pair of four-turn coils.The risk of neutron production when mega-ampere currents are used has led to the use of lower power sources (S/C1130). The possible analytical use of molecular nitrogen in its metastable excited state A3C,+ continues to attract only a limited research effort, which is usually associated with the terms active nitrogen or metastable transfer emission spectro- scopy (MTES).The long-standing uncertainty as to the “best” source of active nitrogen has now been dispelled by Niemczyk et al. (S/C373,86/C1212) who made a comparison of dielectric (DE), microwave (MW) and argon discharge (AD) sources. These sources produced concentrations of N2 (A3Zu+) in the order DE > MW > AD, while the atomic N concentration produced by MW was high, from DE was low and from AD was negligible. Active nitrogen can thus be viewed as a reagent whose properties depend on its method of production. The N atoms are the most chemically reactive species in active nitrogen, but they are also efficient quenchers of the meta- stable N2 state.The most suitable source of active nitrogen for a particular application will thus depend on whether the analyte must be atomised, as is the case for molecular GC eluents, as well as being excited. Recent work has mainly been concerned with the potential of MTES for determining organic atmospheric pollutants and non-metals (SK1143, 86/1389). Atmospheric pressure afterglows, using either Ar or He, have also been applied to the determination of a wide range of non-metals, including the halides (S/C753, S/591). A particu- larly interesting development described by D’Silva et al. (86K1151) was the close coupling of a He afterglow GC detector to a vacuum spectrometer so that resonance lines of Br, C1, F, P and S in the 60-400 nm region could be studied.Three investigations were noted that are of interest for the diversity of the radiation sources used. In the first, electron impact induced fluorescence was used by Gierczak et al. (S/150) as the basis of a GC detector. Fluorescence from the excited molecular fragments CH, CO+, H and OH, produced by a beam of energetic electrons (150-200 eV), was measured in the 300-500 nm range. Tungsten containing 3% Rh was found to be best for the electron-gun filament, yielding electron currents of 1-10 mA. The phrase optical mass spectroscopy was used by the authors to describe the appli- cation of their technique. In the second investigation, a ring-discharge plasma was used by Wrembel (86/C473) to determine Hg in environmental waters, with a detection limit of ca.0.05 ng 1-l. The discharge cell, containing Ar at 1000 Pa, was operated inside a furnace held at 650 “C to prevent the Hg condensing after release from prior amalgamation on gold foil. The ring discharge was maintained by an inductively coupled 60 MHz field having a power density of 0.7 W cm-3. In the third study, Radovanov et al. (86/C568) used AES and a synchronised streak camera to investigate the plasma formed in a pulsed discharge in liquids. In such underwater discharges, the plasma has to expand against the mechanical inertia of the surrounding liquid. With an input energy range of 20-50 J, plasma radial expansion rates averaged 400 m s-1 during the first 10 ps of the discharges, which were through 0.1-1 M NaN03 solution.Plasma excitation temperature and electron concentration were determined by AES to be ca. 2.1O4 K and 1018 cm-3, respectively. The intensity of the Mg I1 280.2-nm line was linearly related to Mg concentration over the range 40-200 yg g-1, suggesting possible analytical uses for this type of discharge. In concluding this part of the review, an interesting example of the application of AES for industrial process control is noted. The report described the use of AES to monitor the composition of TiN films during their deposition by triode ion plating (86/1411). By monitoring the intensity of the N 364.3-nm and Ti 357.7-nm lines, using a glow-discharge plasma, deposition conditions could be varied to produce films of different stoicheiometry.The highest N content obtained in a film corresponded to the formula TiN1.53.126R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 2. PLASMAS 2.1. Inductively Coupled Plasmas Inductively coupled plasma atomic emission spectrometry (ICP-AES) is a mature analytical technique, but there is no sign of waning in the research and development effort devoted to it. The increasing deployment of inductively coupled plasma mass spectrometry (ICP-MS) in analytical laboratories has produced a significant increase in publications so that in total this review encompasses some 560 reports from confer- ences and journals. The provision of computing facilities on ICP instruments has led to increasingly sophisticated data treatments. Calibra- tion.internal standardisation and interference correction are now augmented by optimisation and generalised internal reference schemes, which are increasingly described under the generic name of chemometrics (see section 2.1.4.) in this review. 2.1.1. Plasma characteristics Characterisation of plasmas requires acquisition of relevant data followed by its interpretation. Many reports describe both of these endeavours but some concentrate more on one aspect than the other. To aid in the classification of material, this review will regard plasma diagnostics as being concerned principally with the acquisition of data and mechanistic studies with their interpretation. Mathematical models rarely reflect the detailed properties of plasmas, but they are very useful in defining the boundary conditions and limitations of a particular source. Boulos (86/709) has reviewed the various models that have been applied and with Barnes et al.(S/1218) have computed two-dimensional emission patterns in the ICP for discharges run at 500 and 750 W. Simulated spectra based on a rate model have been described by Lovett (86/C1208), and Cram (S/875) has estimated radiative power losses due to spectral emissions from thermal plasmas. Eckert (86/19) has now published his work on the continuity of analyte transport in the ICP (see also ARAAS, 1984,14,9) showing that between 11 and 55% of the injected analyte passes through the plasma viewing zone yielding, for example, a detection limit for Ca of one atom of Ca per 2 X 1014 atoms of Ar. Mie scattering from the sample aerosol has been used to track particles through the ICP and it was suggested that the transition from the initial radiation zone to the normal analytical zone may be controlled by particle desolvation.Refractory particles were found to pass straight through the plasma, although this did not cause interference for the volatile elements (86/1377). A stochastic approach to modelling particle histories in the plasma was described by Li (S/C255). The measurement of spectral line widths and shapes leads directly to estimates of plasma temperature, collision rates and electron number densities. The recent application of Fourier transform spectrometry (FTS) to ICP discharges should, therefore, greatly facilitate plasma diagnostics. Hor- lick and co-workers have continued their work on the instrumental aspects of the technique and have emphasised the signal to noise ratio (SNR) disadvantage resulting from proportional noise from strong analyte lines being present in all the transformed spectral elements (86/C478, 86/C802, 86/C979, 86/C1240).To overcome this problem they have coupled a dispersive spectrometer having a band pass of 4 nm to the interferometer to limit the spectral range incident on the detector (86/980). In another paper they described a software cross-correlation procedure for the qualitative identification of single-element spectra (861981). Thorne and Harris (86/ C1190) have designed a compact FT spectrometer for the UV region of the spectrum, and Snook and Davies (86/C471, 86K1241, 86/1350) have described a low-noise laminar flow ICP torch for use with this instrument.The laminar flow configuration removes the optical noise component that results from rotation of the outer gas flow in vortex-stabilised torches (see also reference 86/C1236). Faires et al. (861110) measured line widths and shapes of 81 Fe I emission lines and found Doppler broadening to dominate the line profiles and calculated a translational temperature of 6310 k 217 K. Boltzmann plots derived from Fe spectra revealed over- populations of low-level states in neutral atoms increasing smoothly with decreasing state energy. It was suggested that provided this overpopulation is corrected for, the ICP may be used as a source for medium accuracy (better than t25%) determination of oscillator strengths (86/C1243). Parsons et al.(86/C801) advocated manipulation in the Fourier domain as an alternative to full transformation. Instrumental aspects of ICP-FTS are also dealt with in references S/C264, S/C754, 86/C459 and 86/C1239. Hasegawa and Haraguchi (S/876) used an tchelle spectrometer to measure line profiles and deter- mined Doppler temperatures in the ICP of 300&7000 K. Laser-based methods for plasma diagnostics have the considerable advantage that they provide spatially resolved measurements directly without recourse to Abel trans- formation. Hieftje et al. (S/C257, S/C438, 86/1388, 8611394) determined electron number densities and temperatures using Thomson scattering (see also ARAAS, 1984, 14, 10) and emphasised the extreme precautions necessary to avoid stray light.Laser-induced fluorescence has been used to determine rotational temperatures of the OH radical yielding values of 3220 K with gradients of 1000 K mm-1 (S/C410,86/394). The fluorescence technique has proved useful for mapping ground- state neutral atom and ion spatial distributions (861C468). Data obtained in this manner have been used by Hieftje et al. (S/C1149,86/169) to produce correlation maps that enable the calculation of emission intensity based upon the product of the concentrations of the interacting species, e.g., M+, e-. The predicted emission intensity is compared with the measured intensity and this indicates the effectiveness of the particular process. Intra-cavity absorption offers enhanced sensitivity and good spatial resolution and these properties have been exploited by Downey et al.(S/205, S/221, 86/258) in studying the distributions of Ba and Na atoms in an ICP. The temporal characteristics and energy-transfer rates in ICP discharges have been the subject of considerable discussion, but progress in their elucidation has been hampered by trying to determine them from steady-state measurements. A solution to this problem is to modulate thepower to the plasma and observe the time dependencies of the spectral emissions. Hieftje et al. (S/C282, 86/722, 86/C1203) applied sine wave modulation to an ICP (modulation depth 60%) and observed the unexpected result that atomic and ionic fluorescence did not follow the modulation waveform, but rather peaked about 1 ms after the point of minimum power.This delay was found to depend on modulation frequency, height in the plasma and species. Similar parametric dependencies were observed by Olesik (86/C861,86/C1210), and it is intriguing to consider the cause of the length of the delay which is on a time scale orders of magnitude longer than the collisional time scale. Farn- sworth et al. (86/C467, 86/C1218) have taken power modula- tion a stage further using pulsed excitation with the generator off for periods of 200 ps at repetition rates of 60 and 120 Hz. The Ar emission directly followed the power coupling sequence at all spatial positions, but the Ca atom and ion line intensities showed little variation for up to 400 ps after power removal. Both argon and analyte emission exhibited complex oscillatory behaviour after restoration of the power.This year for the first time there are reports of the operation of analytical inductively coupled plasmas at pressures other than atmospheric. Seliskar and co-workers (SlC382, SlC387, S1630, S/663, S/C722, 86/C807, 86/C824) described a reducedJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 127R pressure water cooled torch noting its ability to support plasmas in a variety of gases incuding Ar, H2, He, N2 and Ne. An obvious application of this source is for the spectral excitation of the halogens and a detection limit of less than 1 p.p.b. was obtained for chloromethanes (S1630). Smith and Denton (S/C391, 8611396) operated an ICP in the range of pressures from 0.2 to 4.0 atm and observed an increase in excitation temperatures and shift towards thermal equilibrium as the pressure was raised.A He plasma was readily sustained at 0.2 atm. Methods f o r determining number densities and plasma temperature have been discussed by several groups and there is increasing emphasis on spatially resolved measurements (86/113, 86/695). Optical probes inserted directly into the plasma were described by Rogoff (861364) and La Freniere et al. (861C823). Omenetto et al. (861C1215) employed continuum source atomic absorption to determine number densities of Ar metastable atoms in an ICP. Bastiaans and Mangold (861254) have tabulated data to facilitate electron density and temperature measurements from line and conti- nuum spectra (see also S/C439), but Golbart (S1C714) has pointed out the advantages of using the Inglis - Teller method for electron number density determinations.Imaging systems f o r plasma diagnostics directly provide spatial information enabling mapping of the plasma charac- teristics. Photographic techniques were discussed by Lau et al. (86/C165) whilst Olesik (S/C259, 861C1217) preferred elec- tronic imaging detectors. Laser scattering from Ti02 particles has been used to visualise gas flow patterns in an ICP torch (SlC346) in the absence of the discharge. A novel method of studying dissociation in the inductively coupled plasma named “sample pair modulation” has been described by King and Fry (S/C260). Equimolar alternating transient additions of compounds having widely different bond energies, e.g., CO and O2 produce a modulated emission from the common component (in this case 0) having an intensity ratio equal to the relative stoicheiometry , provided that dissociation is complete.Excitation mechanisms in the ICP continue to be the subject of much discussion, but although various models have been advocated, there is as yet no consensus as to which most reliably represents the truth. Blades and co-workers (S/C261, S/C414,86/C945,86/C1207) have offered convincing evidence to support their near-LTE (local thermal equilibrium) model. This suggests that the analyte channel is close to LTE, but exhibits a slight over population of the lower excited levels compared with LTE and a slight under-ionisation of the elements having high ionisation potentials (see also 86/ C1216).These conclusions are in contradiction to earlier plasma descriptions, but are supported by the author’s experimental data. The near-LTE assumption is also supported by Schram et al. (S/C440) who observed higher than expected recombination rates and attributed these to mole- cular ion formation followed by dissociative recombination. Batal et al. (86/694) suggested that di-electronic recombina- tion might be responsible for some of the very broad lines observed in the spectrum of Zn. The over-population of low-lying states is also predicted by the collisional - radiative model advanced by Hasegawa and Haraguchi (86/699) who suggested that spontaneous emission and collisional excitation (corona type discharge) dominate the populations of the low-lying states whereas direct electron impact is responsible for equilibration of the higher states.In contradiction, Horlick (YC390, 861C1205) compared data from optical and mass spectrometric measurements and concluded that ion - electron recombination dominated soft-line emission and ion - electron impact, ionic emission. Zarouin (86/C1204) and Goldfarb (86/C1220) have pointed out that ICPs at atmospheric pressure also exhibit some capacitive coupling due to a net current flow from the plasma to the surroundings via the analytical zone. Goldfarb (861 C1220) suggested that this might account for non-thermal excitation in the analytical zone and was able to enhance the affect by addition of an auxiliary electrode above the plasma, which resulted in increased emission from Mg lines. The presence of the solvent in the ICP has a considerable effect on the properties of the discharge and it is this reviewer’s opinion that not enough attention has been devoted to the effect of the solvent or its physical form, i.e., aerosol or vapour.Blades and Caughlin (86/106) showed that exchanging water for xylene lowered the excitation temperature and shifted the peak emission profile of the hard lines from 15 up to 20 mm above the load coil. This shift was attributed to a transfer of energy into the C2 dissociation equilibrium. Raising the input power to the ICP by 0.5 kW restored conditions to those achieved in the aqueous loaded plasma. In a further report it was shown that the presence of water did not affect electron densities in the analytical zone (16-20 mm), but they were reduced lower in the plasma in the absence of water (861C1219). This lowering of the electron density was attri- buted to an increase in the plasma volume as the discharge extends further down towards the intermediate tube when water is removed from the injector.Qiu and Trassy (S/C441) postulated that undissociated water at temperatures of 3000- 4000 K represents a considerable thermal buffer in the injector channel. This suggests that dissociation of the water may control the transition to the normal analytical zone. Gunter et al. (86197) have now published their findings (see also ARAAS, 1984, 14, 11) on the effects of easily ionisable elements in the initial radiation zone of the plasma and their conclusions appear to agree with those of Koirtyohann (861C991) suggesting that local increases in the electron density occur, resulting in increased collisional excitation and ambipolar diffusion.Unfortunately, similar increases were not observed by Caughlin and Blades (861263) who deter- mined electron number densities at 4 mm above the load coil in a plasma seeded with 0.5 M Cs solution. There is an increasing body of knowledge on plasmas run in gases other than argon, Although some of these gases, notably N2 and air, are considerably cheaper than Ar, they remain little used in analytical laboratories. This probably represents an economic fact that the cost of gas is small compared with instrument amortisation and staff costs and the costs of changing established methods in favour of new ones that do not appear to offer substantial improvements in performance.Barnes and co-workers have pioneered the use of molecular gases for low-powered plasmas and have recently turned their attention to N2, air and O2 plasmas. Computer modelling and diagnostic studies of these discharges has shown them to be closer to LTE than Ar plasmas and to exhibit lower radial temperature gradients (S/C703, 861256, 861260, 861C1224). High axial temperatures, up to 10000 K for O2 plasmas, higher thermal conductivity and low aerosol velocities, particularly for air plasmas, leads to superior sample decomposition characteristics. Analytical studies on air and N2 (861255) and air and O2 (86/20) plasmas indicated poorer detection power compared with Ar, the order of merit being air > 0 2 > N2.The degradation in detection limits (1-30 times for air) was more marked than for molecular gas cooled plasmas (the molecular gas used only in the outer flow) and Meyer and Thompson (86/20) commented that Ar appeared to be necessary to obtain high sensitivity. When CaO particles of 20-40 pm diameter were introduced into the plasma both air and Ar with an air injector flow provided superior SBRs ratios compared with an Ar discharge, confirming their superior sample decomposition characteristics (86/255). Gold- farb and Goldfarb (86168) have studied mixed Ar - molecular gas plasmas for the analysis of combustion products. They found that concentrations above 0.1% of the additive modify the discharge conditions and may affect the concentration - intensity relationship.Schramel and Xu (S122) studied the affect of H2 addition to all three gas flows of an Ar plasma and128R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 although SBRs were poorer for all elements except Ca and Mg, improved plasma stability led to lower detection limits for Cd, Cr, Fe, Ni and V. Brenner and Erlich (861C1221) have studied mixed Ar - N2 cooled plasmas, but their preliminary results indicated that adding N2 to the outer flow produced poorer SBRs than an all-Ar discharge. The use of He as the plasma gas offers the capability for determining the halogens with improved sensitivity. However, given the high cost of this gas and the availability of alternative techniques, e.g., the MIP, the He ICP is likely to remain of academic interest only (S/129, 86/C806, 86/C1213).This review year there has been renewed interest in axial viewing of the plasma and there is a consensus that this offers improved detection limits by factors of 1-5, and better compromise conditions for multi-element determinations, but an increase in self-absorption leading to reduced dynamic range particularly for the alkali elements (S/152, S/653, 86/190). Snook et al. (86/190) noted that the improved compromise conditions result in a large part from the optical integration along the central channel and they discussed the effect of varying the focal region of the collecting optics. The major uncertainty in analyses of complex materials by ICP-AES arises from the presence of unsuspected spectral interferences.The provision of spectral atlases is therefore of great value to analysts and can save considerable time and effort in checking interferences. A Second Edition of the line coincidence tables of Boumans (S/17) has been published and Brenner and Eldad (S/C1177) have continued their work (see also ARAAS, 1984, 14, 12) on lines and spectral interferences for geological analysis. A spectral database covering the region from 160 to 480 nm for both glow-discharge and ICP sources has been reported (S/C1179) as has an atlas of ICP spectra for the rare earth elements (86/C1184). A comparison of arc, ICP and spark spectra revealed that the arc and ICP spectra were of similar complexity and both were somewhat less populated with lines than the spark spectra (86/362).This disagrees with previous observations on the similarity of ICP and spark spectra. Specific element spectra for Hg (S/C435), Ni (86K1183) and W (S/101) have been described. For some elements the most sensitive analytical lines lie in the vacuum ultraviolet (VUV) region of the spectrum and there have been reports of the determination of S (180.7 nm) (S/921), of P (178.29 nm) (86/25) and of Ge (164.9 nm), In (158.7 nm), Pb (168.2 nm) and Sn (175.8 nm) (86/71). For the non-metals the useful lines occur either in the VUV or infrared region of the spectrum. Nygaard and Leighty (S/C748,86/344) used both VUV and near 1R lines for the determination of halogens whereas Hauser and Blades employed near IR lines for the determination of S (at 921.29 nm) in xylene and subsequently N, 0 and S in xylene (S/307,86/983).A Fourier transform spectrometer has been used to characterise the emission spectrum of an Ar ICP in the 1-2 pm region and 109 Ar lines having signal to noise ratios (SNR) greater than four were observed (86/109). 2.1.2. Sample introduction The ICP exhibits considerable versatility in its sample introduction characteristics accepting analytes in gas, liquid or solid form. Exploitation of this useful property is the simplest way of obtaining improved analytical performance and again this year papers on sample introduction far outnumber those on any other topic. The nebuliser - spray chamber combination remains the standard device for liquid sample introduction and it continues to delight and frustrate users by combining simplicity and robustness of operation with spectacularly poor efficiency (lo%).Poor efficiency, however, is only a problem when sample volume is limited and it enables large volumes of liquid to be pumped through the system, which simplifies the plumbing and helps avoid blockages due to the presence of particulate material. The noise, drift and blockage associated with nebulisers are perhaps their most serious drawbacks in routine use. Theoretical studies on nebulisers and spray chambers are rare, most of the published work being concerned with parametric investigations related to practical problems such as optimisation. Sharp (S/C422) has concluded that spray cham- ber dynamics are dominated by the establishment of a recirculatory flow pattern generated by strong entrainment by the nebuliser free-jet.Droplet deposition is governed by the ability of differing particle sizes to follow the flow lines of the recirculation. The pattern of deposition in the spray chamber thus varies according to its aspect ratio, a short fat chamber exhibits heavy end-wall deposition whereas a long thin chamber produces tangential-wall deposition. A further con- clusion of this paper was that the nebuliser - spray chamber - injector tube should be considered as an entity, the injector playing an important role in promoting the decay of tur- bulence. Results presented by Cresser et al. (86/203) confirmed the recirculatory nature of chamber flow and showed typical aerosol deposition patterns. The same group (see also ARAAS, 1984, 14, ref.C2557) have discussed the measure- ment of nebuliser suction as a means of monitoring nebuliser performance and Gustavsson (86/205) has commented on the difficulties of making a priori calculations of suction from the nebuliser flow-rate. Parametric studies provide direct information on the perfor- mance of a sample introduction system under various operat- ing conditions and can be used to optimise device architecture. Browner and Farino (S/121) have studied the effects of surface tension on aerosol properties and showed that organic solvents produced a shift to smaller droplet sizes whereas surfactants did not. This behaviour may be anticipated because the action of surfactants is time dependent. Following the creation of a new surface there is a time lapse before the surfactant molecules modify the surface layer and lower the surface tension.Nebulisation creates a new surface faster than this process can operate and therefore droplet production is largely unaffected. Lakatos (86/C132) reported that the presence of macromolecules or polymers in the solution enhances the viscosity and reduces nebulisation efficiency so that their prior removal may be necessary. The problems caused by changes in surface tension and viscosity have also been noted by Mermet and Imbert (S/96). Meinhard has discussed the factors affecting the operation of concentric nebulisers (86K1124) and Sommer et al. have reported criteria for selection of nebuliser systems. Routh et al. (S/300, S/356, S/C476, S/C759) employed Fraunhofer diffraction to characterise aerosols from nebulisers and spray chambers.They investigated methods of economising on sample con- sumption and confirmed the well known regulation effect, which in their system resulted in a three-fold reduction in transport for a ten-fold reduction in sample uptake rate (see also references 86/348, 86/C1258). New nebuliser designs continue to be reported and in this review period a new approach to spray generation has been realised in the “Thermospray” by Meyer et al. (S/1232). This device, originally intended for LC-MS interfacing produces a spray from the adiabatic expansion of a superheated liquid. A pump is used to force liquid under pressure along an electrically heated capillary ( T > 140 “C), the pressure suppressing boiling until it occurs explosively at the capillary exit plane.Detection limit improvements of 1.7-6 fold compared with a concentric nebuliser run at twice the sample uptake rate of the Thermospray were obtained. A serious drawback of this device is the necessity to use narrow capillaries (150 pm diameter) to restrict the liquid flow-rate, however, this would not be a problem if the solution was derived from an HPLC column, which would guarantee the removal of particulate matter. Further, it remains to be seen whether the device, which produces high evaporation rates inJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL. 1 129R the aerosol, can cope with high salt content solutions. An advantage that the Thermospray shares with the ultrasonic nebuliser is that the nebulisation does not depend on propellant gas so that the injector flow-rate can be indepen- dently controlled. Browner et al.(S/286,86/C1132) have been experimenting with a monodisperse aerosol generator of the vibrating orifice type and have investigated the effects of drop size on detection limits and on the spatial distribution of emission signals for both hard and soft lines. La Freniere et al. (86/C888) have further described applications of a micro- concentric nebuliser (see also ARAAS, 1984, 14, 14) using it for direct injection of an aerosol (without a spray chamber) into an ICP. Liquid flow-rates were 100-200 pl min-1 and samples were introduced to the carrier stream by flow injection. Performance was claimed to be similar to conven- tional systems, but once again the practicality of the device may depend on the use of particle-free solutions.A similar comment can be made on the jet impact nebuliser, which uses orifices in the 25-60 pm range (S/301). A jet-type nebuliser has been described for the generation of powders from molten metals (86180). A new Babington type nebuliser, the “Conespray” (S/C422, British Patent Assignment No. 8432338, 1984) has been introduced by Sharp and works by the entrainment of fluid along the wall of an overexpanded nozzle. Liquid introduced on to the front surface of the nozzle is sucked down into the nozzle throat and there forms an annular fluid ring from which nebulisation occurs. Droplet size studies under identical operating liquid to gas ratios showed it to compare favourably with concentric nebulisers and this was confirmed in analytical applications.A similar cone entrainment nebuliser was described by Gedeon (86/C641). Legere (S/343, 86/C944) reported that using a non-wettable PTFE orifice in a Babing- ton nebuliser prevented the build up of crystalline deposits when spraying fusion dissolutes containing LiB02. A V-groove nebuliser in “Ryton” has been introduced and its effectiveness in handling solutions containing high levels of dissolved solids demonstrated (S/C1197, 86/C171, 86/428). Babington nebulisers are the preferred choice for slurry nebulisation, but Nohe et al., (S/278) used a concentric nebuliser having a liquid capillary bore diameter of 0.5 mm and succeeded in nebulising coal slurries provided the particle size was less than 325 mesh.The problem of injector tips clogging has been overcome by combining a Babington nebuliser with flow injection (FI) and periodically passing steam through the injector (S/99). Ebdon (86/C1196) intro- duced slurries into both ICP and DCP sources and found that the injector tube size played an important role in setting the particle cut-off diameter. With the particular gas flows used, a 3 mm diameter injector was found to pass particles of 8 pm diameter and less. Algeo et al. (86/1463) employed solution pre-heating to facilitate the nebulisation of lubricating oils for wear-metal analysis. Applications of slurry nebulisation have included the analysis of milk powders (S/C1176), coal, coal ash and fly ash (S/C1180), zeolites (86/1442) and refractory oxides (S/C725).Recirculating nebulisers are useful devices for conserving sample and this review year two groups have published descriptions of their designs previously reported at confer- ences. Hulmston and McKillop (86/430) were able to nebulise a 2-ml sample for 20 min into a double-pass chamber and reported sensitivity, precision and stability to be comparable to conventional flow through systems. Zhuang and Barnes (S/881) employed a simple separating funnel shape for the chamber in their design and noted improved signal stability compared with conventional systems. In a further paper from the same group, the expected increase in signal due to evaporation of the solvent (for nebulisation periods of 40-60 min) was observed, but this was overcome by pre-saturating the nebuliser gas (86/C887).Two hydrofluoric acid resistant nebulisers have been des- cribed, one in platinum with a polypropylene spray chamber (S/66) and the other employing sapphire for the nebulising orifice. The frit nebuliser is the only pneumatic nebuliser that offers a significant reduction in droplet sizes although the reasons for this have yet to be explained. Caruso and co-workers (S/1224) found that organic solvents could be introduced into the ICP with improved plasma stability using a frit nebuliser and exploited this property to nebulise alcoholic solvents from an HPLC column (S/1231). They commented however, that even millimolar salt levels will clog the frit and that solvents having high surface tension tend to foam rather than nebulise.Every year there are reports of ultrasonic nebulisers claiming to have overcome the problems of stability and sample changeover. It is to be hoped that Lancione and Skrabak (86/C1126) have succeeded in solving these difficul- ties that blight an otherwise attractive technique of aerosol generation. Miyazaki et al. (86/1413) obtained improved detection limits using an ultrasonic nebuliser to introduce the organic phase into an ICP following solvent extraction of water samples. Much attention has been given to the design of nebulisers and yet it is the spray chamber that principally determines the characteristics of the aerosol injected into the plasma. There has been renewed interest in cyclone chambers (9345, 86/C166) with claims for improved sample transport and reduced wash-out time compared with conventional designs.Temperature stability of the spray chamber is extremely important in ensuring consistency of analytical results and this has been achieved by providing a spray chamber with a water jacket (S/852). There has been further comparison of methods for determining chamber transport efficiency (86/C1131, see also ARAAS, 1984,14,12) and efficiencies of over 50% have been obtained using aerosol desolvation (86/C862). Steele and Hieftje (S/377) have again discussed (see also ARAAS, 1984, 14, 15) applications of sample modulation using a spray chamber containing a motorised piston. Organic solvents present particular problems because their volatility can lead to excessive solvent loading in the plasma and cause instability or extinction of the discharge.Maessen et al. (S/C423) have continued to study this probelm (see also ARAAS, 1984, 14, 15) and have determined plasma loading for various solvents and shown how these may be controlled by thermostatting the spray chamber. Magyar and Lienemann (S/C475) confirmed the beneficial effect of adding 0 2 (1% V/V) to the injector flow to combust carbon from organic solvents and thereby reduce background emission and prevent the formation of carbon deposits. They also combined 0 2 feeding with aerosol desolvation obtaining further gains in sensitivity. Meyer (86/C1161) has advocated the use of an all air plasma (40.68 MHz) for organics noting that the presence of organic materials produced no observable changes in the discharge.Xylene is the solvent most commonly used for diluting oils prior to analysis by ICP-AES, but Botto (86/C1160) preffered tetralin, which has a lower vapour pressure than xylene and found that plasma cooling and the decrease in emission intensities were much reduced. The generation of volatile species for introduction into the ICP is a common method of improving sensitivity. Hydride generation (S/889, SA091, 86/1365) is the most widely used procedure and a mathematical model of the signals produced by continuous hydride generation has been described (861 C477). A continuous hydride generator described by Huang et al. (86/C1128) employed a conventional nebuliser with an impactor having a collection bowl into which the reducing agent was independently pumped.Improvements in detection limits of 20-50 times compared with conventional nebulisation were obtained. Sanz-Medel et al. (86/207) have further investigated (see also ARAAS, 1984,14,16) the production of volatile Mo species in solution as a means of improving the transport efficiency of a conventional nebuliser - spray chamber system. Molybdenum hexacarbonyl in butan-1-01130R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 was found to be the most useful combination producing up to a four-fold increase in sensitivity. Miles and Levin (861C595) determined sulphide in natural waters by reduction with 1 ‘/o V/VHCl and injection of H2S into the plasma. Organic carbon in waters has been determined by oxidation in a reactor containing copper oxide at 850 “C, which converts the carbon into C 0 2 for introduction into the plasma.The detection limit for this method was 0.3 pg ml-1. Similarly, carbonate has been determined by decomposition with HC1 and introduction of the evolved C02 into the plasma (SK471). The direct injection of solids into the ICP appears to be an attractive technique offering savings on sample preparation time, improved sensitivities and the avoidance of contamina- tion. Practical experience, however, shows that these poten- tial advantages are outweighed by the difficulties of calibra- tion, of sample inhomogeneity and segregation and of standardising the sample loading in the plasma. Nevertheless, there have again this year been reports of the introduction of powder samples into the ICP (S/604, 91233, 86/C266, 86/C880) and in a survey of methods for the direct analysis of solid materials, Zil’bershtein (S/1233) described the direct transverse insertion of analytes machined into thin rods.Electrothermal vaporisation (ETV) for sample introduction provides substantial improvements in detection limits and enables the analysis of small sample volumes. Previously, standard, commercially available atomic absorption furnaces have been used, but increasingly they are being modified to meet the specific requirements of ICP sampling. A problem that has not yet been resolved is the provision of background correction for the transient signal produced by ETV devices. Broekaert et al. (S/C305, 86/C474) described a dual-channel spectrometer system capable of simultaneous background correction and although the system was used with discrete sample nebulisation, it could prove equally effective with ETV.Wohlers et al. (86lC871, 86/C1134) preferred an oscillating refractor plate for rapid background correction (see also 86/C865, 86/C1130). The acquisition of time resolved emission profiles has been advocated to take advantage of the differing “appearance times” of the elements from ETV thereby avoiding spectral interferences (S/C297, S/C1183, 86/1274). The use of the term “vaporisation” stresses the fact that the sample introduction device need only produce a vapour, leaving atomisation to the ICP. Indeed recent work by Snook et al. (86/108, 86/C517) has shown that atomisation is deleterious to transport of the analyte because of absorption of the atomic vapour on the containing walls.The production of highly dispersed aerosols, rather than vapour, is preferred and it was shown that this is encouraged by the addition of selenate or sulphide ions to the sample. The addition of a Ta coating to a graphite rod vaporiser further inhibited atom formation, favouring the formation of molecular or agglomer- ated species. Comment was made on the necessity of keeping volumes and gas flows low so as to increase the atomic density and residence time of the analyte in the plasma. This point has been discussed by Matusiewicz and Barnes (86/442) who described a contoured wall tube furnace vaporiser. Profiling the wall produced uniform heating of the tube and avoided the occurrence of multiple emission peaks due to condensation of vapour on the cooler parts of the wall surface.The same workers obtained improved response for volatile elements using platform atomisation (S/C719, S/1096), but found that aerosol deposition with ETV yielded poorer limits of detec- tion than the normal injection technique. The aerosol deposition technique has been applied to the analysis of drinking water (S/C290, S/C309, 86/C187, 86/C895). Electro- chemical pre-concentration has been combined with ETV by transferring a mercury drop containing adsorbed cations into a graphite cuvette, where the mercury was evaporated prior to placing the cuvette into a tube furnace (86/C867). Improve- ments in detection limits of 1-2 orders of magnitude were obtained in comparison with direct injection into the furnace.The ETV-ICP technique has been combined with photo- graphic detection for survey analysis (S/171) and has been applied to environmental samples (86/971) and to the determi- nation of Hg (86/221) and S (S/909). Metal vaporisers are less common than their carbon counterparts, but there have been reports of a tantalum vaporiser (S/128), on the use of a platinum filament vaporiser for the determination of P in semiconductors (S/C285) and of a tungsten boat vaporiser that was employed in the determination of U and Th (SlC369). Direct sample insertion devices have the advantage that they remove the necessity of using ancillary power supplies to vaporise the sample and there is no problem of sample transport. They can also be conveniently used with slurry or powder samples.Unfortunately there is evidence that because of their thermal mass and the poor conductivity of the plasma gas, these devices do not reach such high temperatures as ETV devices, This is a particular problem with solid samples and analytes reach the plasma by boiling out from the matrix rather than by complete vaporisation of the sample. The use of thermochemical reagents, as employed in d.c. arcs, will no doubt be discovered once again. For example, Nickel et al. (86/C640) used 59Fe to study retention in a graphite matrix and found that the addition of 2% NaF and 2% (CZF4),, reduced the retention of Fe to less than 1% compared with 35% for an undoped matrix. McLeod et al. observed that chips of nickel-based alloys formed molten globules from which Cd, Mg, Pb and Zn vaporised readily (S/C469), but in which As, Sb, Se and Te were retained.Retention of the matrix was used to beneficial effect by Lorber and Goldbart (S/C470, S/C708, S/1106) who employed the carrier distillation technique with a transversely inserted graphite cup for the determination of impurities in uranium oxide. Brenner et al. (86/C178,86/C647, 86/C756, 861C864, 86/C1137) experimented with silicate materials, but noted that the response depended on the mineralogical history of the samples and element volatility. Horlick and co-workers (S/C304, 86/648, 86/C1136) investi- gated the determination of volatile elements (Ag, As, Cd, Cu, Ge, In, Li, Pb, Sn and Zn) and found that matrices of graphite, alumina and silica did not affect the responses, although it is not clear whether these elements were chemi- cally combined with the matrix or simply admixed.The same group described the collection of laser ablated material on to a direct insertion device for subsequent introduction into the plasma. Less refractory materials are easier to analyse and Ca, K, Mg and Na have been successfully determined in plant samples placed in graphite cup fitted with a lid to prevent ejection of the powdered material (86/386). Controlled potential electrolysis on to a vitreous carbon direct insertion device has been used for the pre-concentration and determi- nation of heavy metals. Detection limits of 2.4, 680,2.0, 175, 25 and 259 ng ml-1 were obtained for Ca, Cd, Co, Ni, Pb and Zn, respectively (86/374, 86/C1138). Wire-loop insertion devices have lower thermal mass and heat up more rapidly than the larger graphite based designs.Salin et al. (86/157, 861C930, 86/C931, 86/C1135) obtained peak widths of 0.1 s with tungsten and tantalum loops and applied these to the determination of trace elements in biological materials includ- ing urine and hair. Arc and spark sampling are now established methods for introducing conducting materials into the ICP. Although there have been many analytical studies of these techniques there have been few investigations of their sample transfer characteristics. It is encouraging therefore that Watters and Turk (86/C825) have studied the aerosols produced by spark sampling. They found that the erosion rates for pure metals varied by more than an order of magnitude and this led to systematic errors in the analysis of alloys.The spark aerosol was found to contain particles of 0.01 pm diameter although clusters of particles up to 0.1 pm diameter were also present. The importance of well matched standards in these circum- stances has been noted (S/C394). Takahashi et al. (86/1012)JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 131R used a low-voltage spark to sample high-speed steels and found it necessary to use a cyclone to remove agglomerated particles in the aerosol. Keeping the aerosol delivery tube short was advocated and there was evidence of the selective adhesion of W on the stainless-steel tube walls. Non-conduct- ing materials may be sampled by mixing with a conducting substrate and this approach has been used for the analysis of ferromanganese nodules (86K1139). Reports of the analysis of metals can be found in references S/C303, S/C731, S/C783, S/1121, S/1233,86/C879 and 86/C946.Arcs have been less used for sampling than sparks, perhaps because the generation of heat and larger sample erosion rates are not so compatible with the ICP. Nevertheless a d.c. arc was used for the analysis of aluminium and aluminium alloys and it was found that a 4-A arc produced a sampling rate of 4.5 pg min-1 into the plasma (86/C267,86/C619). Detection limits in the aluminium were 5 , 0.9, 7, 0.3, 2.5 and 28 pg g-1 for B, Cu, Fe, Mg, Mn and Si, respectively. There have been further reports of the r.f. arc described by Hieftje and co-workers (S/C398, 86/C1140) (see also ARAAS, 1983, 13, 13.Laser ablation is the simplest method of producing aerosols directly from non-conducting materials, particularly those in bulk form. Normally, the aerosol is produced as a single pulse of vapour, but with the high repetition rates available from Nd: YAG lasers it may be possible to produce quasi- continuous sampling. Cremers et al. (86/1452) reported the ablation of steel samples using a Q-switched Nd : YAG laser, which provided a pulse repetition rate of 5 kHz. The method was also applied to liquid steel samples and the results compared with those obtained directly from the laser gener- ated plasma (S/C1127). Laser ablation for metal analysis has been the subject of a European patent application (86179).Horlick and Lepla (S/C315) used a “spray chamber” to remove the larger particles from the aerosol for the analysis of aluminium alloys. They obtained non-linear calibration curves for Si and it may be that segregation effects in the spray chamber were partly responsible. The separation of larger particles from solid aerosols is not species independent as for liquid aerosols. Conversely, Thompson (86/C808) applied ablation for geochemical analysis and commented on the merit of obtaining almost 100% sample transport to the plasma. 2.1.3. Flow injection and chromatography Previously in the ARAAS reviews flow injection (FI) and chromatography have been dealt with separately, but the increasing combination of FI with ion chromatography and pre-concentration techniques has blurred the distinction.Flow injection is no longer simply an alternative sample introduc- tion technique, but must be regarded as an adjunct to the sample preparation process. For example, Hartenstein et al. (S/213, S/C287) combined flow injection with miniature Chelex 100 ion-exchange columns and obtained 20-fold improvements in sensitivity for Al, Ba, Be, Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn, the detection limits were 20,0.04,0.008, 0.04, 0.1, 0.2, 0.5, 0.04, 0.2, 2 and 0.5 ng ml-l, respectively. Similarly, an on-line microbore column of activated alumina has been used to separate and pre-concentrate P from solutions containing dissolved steel samples (311 17). The same column materials proved useful for separating Cr(V1) and Cr(II1) (S/1234) and in the pre-concentration of V as the vanadate anion (86/C141).In conventional FI, gas displace- ment driven carrier flow has been advocated as an alternative to using a peristaltic pump as a means of obtaining improved precision (S/C778). The flexibility of FI systems is well documented and this has been utilised in hydride generation (S/C711), in liquid - liquid extraction (8611023) and in the analysis of biological materials (86/220, 86/C863). The central problem of coupling liquid chromatography to ICP-AES is the sample introduction interface (86/C1143). Conventional pneumatic nebuliser based systems are only 1 YO efficient and this leads to a substantial loss of sensitivity. This problem is now being addressed and there are several reports of improved interfaces. The frit nebuliser is the most efficient of the pneumatic types and has been shown to work well with organic solvents (S/C730, 86/45).Koropchak and Winn (86/C883) have attempted to use polymeric frits rather than glass ones as a means of reducing the troublesome memory effects to which frits are prone. These workers also experimented with a thermospray nebuliser (see section 2.1.2.), which might give significant gains in efficiency. Direct injection (no spray chamber) nebulisers have been used by Jinno et al. (86/728) and La Freniere et al. (86/C917) who found that detection limits based on a net 30-35 pl sample consumption were only 2-3 times poorer than those obtained by conventional nebulisation. It should be emphasised that the well-filtered, particulate- free solutions produced from chromatographic columns give greater scope in the design of nebulisers and largely remove problems associated with the use of fine capillary tubes for the liquid phase.Browner et al. (86/C843, 86/C892) have advo- cated the use of a mono-disperse aerosol generator (see section 2.1.2), which offers 100% transport efficiency and the potential for reduced solvent loading of the plasma through controlled evaporation. Excessive solvent loading is the drawback of achieving high efficiency. This is particularly so when the solvent is volatile, but this problem has been circumvented (at the expense of sensitivity) by post-column mixing of the carrier solvent with one of lower volatility, e.g., xylene (86/C642). Kosman et al. (861C1155) discussed internal standardisation for LC-ICP, comparing addition of the standard continuously to the mobile phase and to the samples.Various applications of chromatography coupled to the ICP have been reported, notably the speciation - separation and determination of mercury compounds (S/C334), of sulphur and vanadium compounds (S/865 and Fe, Ni, S and V (86/C1162) in petroleum crudes, of rare earth elements (S/901, S/1227,86/C1147), of S in surfactants (86/C1154), of Se in urine (86/C1227) of organoarsenic compounds (86/1331), of trace elements (86/C643) and of trace elements in water (86/C 174). 2.1.4. Chemometrics Optimisation is a necessary and time-consuming step in method development. Modern computerised instruments should be capable of performing this task unaided, but manufacturers have been slow to incorporate the necessary software.This situation now seems to be changing. Collins and Kisslak (S/C389) and other workers (S/C774, 86/C1176) described what they termed a second derivative, conjugate vector search algorithm. This procedure evaluates three-point response functions for each parameter in turn, locating the optimum settings by fitting a parabola to the data. The cycle is then iterated to produce the necessary convergence. The Simplex algorithm is the most widely used and works well provided that a suitable objective variable can be defined. The selection of appropriate variables has been examined by Routh (S/C772). Moore (W1174, 86/369) Simplex optimised an Ar - N2 plasma using SBR and then subsequently the minimisation of matrix interference as the objective variables.It was found that a reduction in interference level to <8% could be achieved with a less than a 25% reduction from the maximum SBR. A change of nebuliser to a more efficient design resulted in a shift of the optimum conditions to higher power, which then resulted in significantly improved results. A combination of Simplex and factorial designs was used to optimise an Ar - H2 plasma (86/1354). It was found that the conditions appropriate to Ca were a good compromise and produced improved detection limits for Be, Cd, Cr, Fe, Ni and V. A similar combination approach has been used to optimise conditions for transient signals (86/C1186). Simplex optimi- sation discards the poorest response data as the algorithm proceeds, but Smith et al.(S/C775, 86/C838, 86/C1175)132R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 described a procedure termed Optiplex, which uses all the data, fitting it to polynomials to predict new parameter settings. This appears to be similar in principal, if not in detail to the super-modified Simplex previously described by Den- ton and co-workers (Routh, M. W., Swartz, P. A., and Denton, M. B., Anal. Chern., 1977, 49, 1423). Univariate search procedures continue to be reported even though it is doubtful that these provide true optima without skilled interpretation of the data by the analyst (S/19, S/C459, S/C713, S/878). It has usually been accepted that the “soft” lines of the alkali metals require different excitation condi- tions to lines of higher excitation potential.Fassel and Winge (86/C847) advocated a position of low background higher in the plasma, but Nygaard and Leighty (S/1119) favoured the normal analytical zone because of the reduced interferences, precision and linearity of calibration. Instrument calibration should be a straightforward task, but it is important that the physical and chemical characteristics of the standard are close enough to the samples to control those interferences that cannot be overcome by optimisation or data correction. These points have been discussed in relation to the analysis of steel by Lippert (S/C396). A combination of careful control of the injector flow-rate and monitoring atom to ion line intensity ratios to fix the spatial location of the plasma zones has been used to control calibration drift in an ICP to less than 5% (S/C427).Sermin (86/C486) has advocated the visual display of computer generated calibration curves along with the raw data points as a means of noting outliers. A method for plotting multi-element calibration curves in multi-factor space that allows both qualitative and quantita- tive analysis to be performed has been described (S/C393, 86/1384). A generalised standard additions method (Kalivas, J. H., and Kowalski, B.R., Anal. Chern., 1981,53,2207) has been used to calibrate an ICP spectrometer for the analysis of geological materials (S/C1178). Multi-factor correction should offer superior performance to conventional internal standardisation. Thompson and Ram- sey (S1186, 86/189, 86/C822, 86/973, 86/C1247) employed principal components analysis as an aid to identifying the parameters responsible for drift and instability in the ICP.They found that variations in forward power and analyte uptake rate accounted for most of the variation and that these were well correlated with the emission intensities of the Zn I1 202.5- and Li 1670.78-nm lines, respectively. Using these two lines as internal standards in what was termed the Parameter Related Internal Standard Method (PRISM), the medium term variation was reduced and the precision obtained on 24 lines over 4.5 h was 0.005. They also found that there are similarities between the susceptibilities of elements to matrix effects and their variation with forward power, thus the PRISM approach was also used for matrix correction. Lorber and Goldbart (S/c424, S/C705, S/C798, 86/C803, 86/1006) have continued work on their General Internal Reference Method (GIRM) (see also A R A A S , 1984, 14, 19) and have improved the computational procedure enabling real-time operation.They claimed that the method provides for accurate background subtraction, removal of non-random noise, the characterisation of low-frequency noise and that improvements in detection limits by up to a factor of 20 can be achieved. The Myers - Tracy signal compensation technique, which requires simultaneous measurement of the Sc I 424.683- nm line and the Ar background spectrum in the 419-420 nm region, has been shown to provide improved precision, particularly in high salt content solutions (S/C302, S/C426, S/C1141,86/C465).Scandiutn has also been used as an internal standard in the determination of S (S/834). The correction procedure described by Botto (86/102) that compensates for sample introduction rate and acid concentration by measure- ment of the intensity of the Hp line has been published (86/102). The importance of obtaining positive correlation between the internal standard and the analyte line has been stressed (S/C425, S/C710, YC1184, 86/C463) and it has been demonstrated that correction for long-term drift is possible by sequential line measurements on a scanning spectrometer (86/C461, 86/1353). Drift compensation in the analysis of minerals (86/C460), the determination of Y (S/C1137), compensation for the effects of HC1 and H2S04 (861725) and the use of chemometrics in process control (86/C1172) have been discussed.There have been several previous reports of noise power spectra of the ICP (see A R A A S , 1983, 13, 16), and data from Barnett et al. (86/C462) confirmed previous findings that the spectrum consists of white noise with superimposed com- ponents due to plasma rotation and a llfcharacteristic at low frequencies. The over-all noise magnitude was proportional to analyte concentration. McGeorge and Salin (86/114) deter- mined the background emission photon flux of the ICP in the 200-450 nm range and calculated minimum integration times necessary to avoid shot-noise limited measurements. They concluded that blank integration times would in general be shorter than those required for samples and would be subject to considerable variation depending on the spectral region and instrument parameters.Unsuspected spectral interferences are the major source of inaccuracy in analyses performed by ICP-AES. Boumans and Vrakking (S/C411, 86/700, 86/701, 86/C1164) have continued their work on the effect of resolving power in reducing problems of spectral interference. They demonstrated that in the presence of spectral overlaps the limit of determination may be 1-2 orders of magnitude greater than the limit of detection and that the main benefit of high resolution is in improving the former. Physical line widths in the ICP vary between 0.001 and 0.005 nm and there have been assessments of the extent to which practical spectrometers achieve spectral bandpasses of this order (S/C432,86/C998).Parsons and Park (S/C280) reported further investigations of the spectral interferences of the Group IVA and VA elements and there have been discussions on the use and limitations of current spectral libraries for predicting interferences (S/C773, SA093). Specific discussions of line selection and interferences have been presented for environmental materials (S/C397), Pu (86/C803) and geological materials (S/C415, S/C707). Computer methods for spectral filtering (86K488) and regres- sion based methods for spectral interference correction have been described (S/915, 86/C1185). 2.1.5. Inductively coupled plasma mass spectrometry (ICP- MS) In A R A A S , Volume 14, there were some 26 references to ICP-MS mostly from research groups and manufacturers.In this review year that number has increased to 84 and with more instruments being delivered to applications laboratories it seems likely that this rate of growth will be maintained. That the technique is still in its infancy is reflected in most of the reports being from conferences, but no doubt many of these will find their way into JAAS and other journals within the year. The current status of ICP-MS has been reviewed by Gray (S/C418, 86/C541) and Douglas and Houk (86/674, 86/1380). The difficulty of optimising ICP optical systems is well known, but the problem is compounded for ICP-MS when the position of the sampling cone and the parameters of the interface are included. Horlick and co-workers (S/C293, 86/C167, 86/C552, 86/C789, 86/C821) have studied the effect of operating parameters and noted the following. The most critical parameters were the nebuliser pressure and the power.Plots of ion count against these two variables showed similar behaviour for the light elements (Li, Na, B, Mg and Al), the first-row transition elements (Ti to Zn) and the alkalis (Li to Cs). However, going down the columns of the transitionJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986. VOL. 1 133R elements (Cr, Mo and W, and Cu, Ag and Au) changes occurred with Mo and Ag, and W and Au exhibiting similar characteristics. Elements such as Ba and Sr, which have second ionisation potentials below that of Ar+ and tend to form M2+ ions exhibited an anomalous response. The effect of operating parameters on ion count rates for singly charged ions, doubly charged ions, oxide ions and analytical perfor- mance have been discussed (86/C1107, 86/C1120).Studies of ion-extraction interfaces have been presented by Olivares and Houk (86/1378), Osawa et al. (86/C1181) and Mermet et al. (86lC549). A new ICP-MS instrument has been described that enables simultaneous optical observation of the ICP and the 1 Torr region behind the sampling cone (86/C796, 86/C1105). This should facilitate study of the formation of molecular ions in the expansion of the plasma gas in the first vacuum stage. Interferences in ICP-MS arise from matrix effects, particu- larly due to ionisation suppression, from the formation of stable oxides and from spectral interferences due to the presence of molecular ions often derived from the solvent.A model for ionisation suppression has indicated that the observed effects are in accord with the temperature in the first vacuum stage (200-400 K) rather than that in the plasma itself (86K1210, 8611381). Another interesting observation in this work was that Ar ions are the most suppressed species, as would be expected, and that easily ionised elements may dominate the ion population in the central channel. Although these findings suggest a well defined mechanism, other groups have noted that matrix concentrations of 1000 pg ml-1 can produce depressions of 15-30% regardless of ionisation energy (86/C555, 86/C1103, 86/C1121) whereas Ca has been found to produce enhancements (86/C1121) as has acetic acid (86/C551).Clearly, it will be some time before a coherent explanation of these observations emerges. Although it has been suggested that the molecular species observed in ion spectra may exist in the plasma (S/C295), there is strong evidence that they originate in the ion extraction interface. Thus, Gray and Williams (86/C1104) have shown that improved interface design can reduce the relative levels of molecular ions and Houk et al. (86/C1114) suggested that auxiliary ion beam dissociation and the use of additional gases, e.g., Xe, might also be effective. The presence of molecular ions causes spectral interferences that reduce the sensitivity of some important elements notably Ca, Fe and V (S/C462, 86/C792). Potential spectral interferences in ICP-MS have been tabulated (86/C553).Sample introduction for ICP-AES is the most critical determinant of technique performance and this is even more so for ICP-MS because of the solvent derived interferences. Boorn et al. (86/C1133) discussed sample introduction tech- niques and found that with regard to nebulisation, the lessons learned from optical spectroscopy also apply for MS. However, to reduce plasma loading of organic solvents they employed reduced sample uptake rate (0.5 ml min-I), a cooled spray chamber (-30°C) and introduced 0 2 to the injector flow to combust free carbon. The most satisfactory way of reducing solvent loading is to use electrothermal vaporisation, which also yields improved sensitivities. A graphite rod vaporiser (86/C797, 86/C1193) has been des- cribed and there has been a comparison of a rhenium filament and a graphite-rod vaporiser (S/C291).Detection limits in the sub-p.p.b. range were obtained using 1-5 1.11 samples. For bulk non-conducting solids, laser ablation is a convenient technique for direct sampling and Gray (86/196,86/C793,86/C1118) has obtained detection limits down to the 10 ng g-1 level. Major elements proved difficult to determine because of saturation of the detector at high ion currents. An intermittent arc discharge has been used to sample steel samples and produced linear calibration graphs for matrix elements up to a level of 0.1% (86K1141). Metal oxide formation was reported to be negligible even for Mo, W and Zr and the levels of 0+, OH+, H20+ and ArH+ were greatly reduced compared with aqueous sample introduction, their concentration being re- lated to the quality of Ar used.Stability of operation has been a problem for users of the first production instruments although progress has been made, Meddings et al. (S/C1183), for example, obtaining short-term precisions of the order of 0.005-0.01. Precision is particularly important in isotope ratio determinations and various reports agree that the obtainable precision, e.g., for Pb isotope ratios (86/C1113), is of the order of 0.005 (S/C464, S/C743, 861C1112, 861C1117). Russ and Bazon (86/Cllll) emphasised the need for caution in determining ratios with relatively high ion currents because of the long dead time of electron multipliers. They calculated that at a count rate of 1 MHz and with a dead time of 150-200 ns, a 15% correction would be needed on a ratio as low as four.The improved accuracy obtainable with isotope dilution analysis has been demonstrated for natural waters (86/C180, 86/C548, 86/C754, 86/C1108) and for marine samples (S/C419,86/C164,86/C546, 86/C791, 86/C1116). The determination of enriched isotopes of Cu, Fe and Zn used as tracers in human metabolic studies has been demonstrated (86/C1110). Most of the reported applications of ICP-MS have been to geological/ environmental materials (S/C461, S/C1182, S/C1186, 861115, 86/C154, 86/C547, 86/C790, 86/C1109, 86/C1260, 86/C1264, 86/C1265, 86/C1267), but there have also been reports of the analysis of metals and semiconductors (S/C463) and of acid rain samples (86/C1159). Fast protein liquid chromatography (FPLC) has been coupled to ICP-MS for the analysis of foods (861C1119).2.1.6. Inductively coupled plasma atomic fluorescence spec- trometry (ICP-A FS) The principal difficulty in using atomic fluorescence spec- trometry is in obtaining satisfactory sources for a wide range of elements. The most promising approach is to employ two plasmas, one for atomisation and one for excitation (see ARAAS, 1984, 14, 20). Greenfield (86/C1244) has advocated the use of a large torch - high power ( 5 kW) configuration for the source plasma to achieve higher spectral radiance and demonstrated the benefit of adding hydrocarbons to the atomiser plasma to prevent the formation of refractory oxides in the extended tail flame. There have been further reports of the system developed by Winefordner and co-workers (86/ C792).Hollow-cathode lamps are certainly easier to use and Demers (S/C344) employed boosted output lamps constructed to the design of Lowe (Lowe, R. M., Spectrochim. Acta, Part B , 1971,26,201) and reported enhancements in output up to 20-fold, which yielded significant improvements in detection limits. D’Silva et al. (S/C288) employed Raman shifted laser radiation to achieve spectral coverage in the 180-360 nm range, but it seems unlikely that such a source will find use in applications laboratories. Sample introduction has once again been found to influence performance strongly, and ultrasonic nebulisation with desol- vation yielded the expected order of magnitude improvement in sensitivity (86/191). It was also noted that the addition of carbon containing gases, or the use of a graphite injector could prevent the formation of stable oxides in the atomisation torch whereas oxygen addition was necessary to prevent carbonisa- tion with organic solvents (S/C296, S/1217).Applications of ICP-AFS have included the determination of secondary elements in nickel plating baths (S/142), of Fe, Ni and V in refinery feedstocks (S/C296), of Hg (86/24), of trace elements in alkali chlorides (S/C360) and of elements in environmental samples (86/34) and in air filters (86/C830). 2.1.7. Instrumentation The most noticeable development this year has been the use of ICP-AES in on-line process control. Routh and Steiner134R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 (91098) assessed the capabilities of the ICP for this appli- cation and concluded that the ICP needed a laboratory-type environment for successful operation. This implied transport and modification of the samples rather than the source and spectrometer. Meyer et al. (9873, 86/C1173) described the determination of Ca and Mg in a 2% dissolved salt stream and of Na in a pre-diluted 45% calcium salt stream (86/C614). Air plasmas have obvious advantages for on-line applications and their use for monitoring brine streams has been demonstrated (86/C1174). Kondo et al. (S/882) described equipment for the on-line analysis of plating bath solutions. Radiofrequency generators continue to be developed, thus Gagne and Morrisroe (S/C395) described a new high perfor- mance computer controlled power unit whilst Brown et al.(86/C882) emphasised the benefits of a free-running Kuhn oscillator for coping with the impedance changes caused by the introduction of organic solvents. An impedance matching unit for remote coupling of an ICP has been described (86/984) and Allen and Coleman (9126) ran two plasmas from one generator using them in tandem for sampling and excitation. Low-flow, low-power and miniaturised inductively coupled plasma torches have been around for some time, but whereas low-flow standard sized torches have gained some acceptance in user laboratories, the miniaturised and externally cooled types have not. The comments made in section 2.1 concerning the use of gases other than Ar apply equally here and it seems that only a commitment by a major manufacturer could produce a change in the standard equipment.It is interesting to note, therefore, that Goulter et al. (S/C317, 86/C818, 86/C890, 86/C1191) have presented analytical data for a mini-torch claiming its performance to be similar to that of a conventional design. Ng et al. (S/1097, S/C1173) have publi- shed further data for their low-flow torch operated with organic solvents noting that stable plasmas could be operated with xylene down to 0.3 kW forward power. Analytical data (S/581) and interference studies (86/111) on a low-flow, low-power torch indicated a performance similar to conven- tional torches and it was found that the type of sample introduction system used had a strong effect on the nature and magnitude of the observed interferences.A high-efficiency torch that uses additional concentric tubes has been described by Falk (S/236). Mermet and co-workers (S/C478, S/C1198, 86/C1211) have again emphasised the benefits of using higher frequencies for low-flow and low-power torches. Analytical data for an 80 MHz 9 mm torch have been presented (S/C477). Comparisons of ICP data are difficult because of the different torches and sample introduction systems employed. The efforts of Rayson et al. (WC336) to introduce a standard torch configuration for diagnostic studies are welcome, but there may be difficulties in extending the standardisation to the nebuliser - chamber. There have been further reports of externally and radiatively cooled torches (S/C420, 86/C446) and claims that their analytical performance matches that of conventional designs (86/C472).2.2. Microwave-excited Plasmas 2.2.1. Fundamental studies Characterisation of microwave plasmas has normally been performed on the discharge as a whole, but there is now a greater emphasis on spatial variations. For example, Mat- ousek et al. (S/189) vaporised C, Cu and Mn into an MIP and noted that the vapour was rapidly lost from the plasma and implanted into the silica wall. It is not clear whether the discharge body was contacting the wall, but the conditions under which this occurs have been studied (S/138). Plasmas generated by a surfatron have been studied and a variety of plasma geometries including rod, annular, filament and stabilised filament were obtained (86199). Spatially resolved diagnostic studies of these plasmas indicated that the con- tinuum in the visible part of the spectrum cannot be attributed entirely to radiative recombination.An annular He MIP sustained in a surfatron was shown to accommodate aqueous aerosols at powers down to 100 W and to exhibit a spatial emission characteristic similar to an ICP. The He background spectrum peaked in the annulus, but the atomic and ionic lines of metallic elements exhibited their maximum intensities at the discharge centre. Brown et al. (S/C385) determined temperatures in a medium power (500 W) MIP obtaining an excitation temperature of 14 000 K and a rotational tempera- ture of 3570 K. Comparing this with low-power devices for which T,,,. = 5000 K and Trot, = 1500 K, they concluded that the higher power rendered the device more suitable for the thermal volatilisation of samples.A plasma of this type has been used as an ion source for mass spectrometry (S/C744, 86/C1106). A study of the effect of pressure (10-760 Torr) on plasma characteristics revealed that the excitation tempera- ture varied little, whereas the electron density was linearly dependent on pressure. A notable change occurred at pressures below 100 Torr with radiative effects becoming dominant. Excitation mechanisms in low-pressure MIPs have been reviewed (S/603) and the use of electrical probes for plasma diagnostics discussed (S/C704). There has been increased interest in the use of gases other than Ar or He. Nitrogen (86/22) and air plasmas (SIC386, 86/28) have been sustained at medium powers (200-500 W) in a torch configuration similar to that used for the ICP, but on a smaller scale (4 mm i.d.).It is claimed that these molecular gas plasmas are closer to thermal equilibrium than their rare gas counterparts and, therefore, offer better atomisation effi- ciency for aqueous aerosols (S/C384, S/C386) although matrix interferences requiring the use of releasing agents were still observed (86/218). An investigation of noise sources in an N2 plasma revealed it to be flicker noise limited below 1 Hz with peaks at 60 and 120 Hz from the power supply. Spectral studies of MIPs have characterised the near- infrared emission lines for Br, C, Cl, F and S (S/C262,86/100, 86/117,86/1048). Timmins (S/C436) found that the ratio of the Br 1477.8-nm line to the Br I1 470.5- and 478.5-nm lines was strongly dependent on both He flow-rate and analyte concen- tration.An MIP has been used to characterise the spectrum of neutral As in the range 164.4 nm-3.6 ym (86/402). 2.2.2. Instrumentation Recent developments in torch and cuvity design have suc- ceeded in producing MIPs with annular forms similar to that of the ICP. As for the ICP, these annular plasmas show a greater tolerance to the introduction of samples and enable nebuli- sation to be used for aqueous samples. Carnahan and co-workers (86/118) have published a description of tangential flow torches operating at 500 W and producing annular plasmas in Ar and diffuse elipsoidal plasmas in air, He and N2. A miniature copper torch, similar to an ICP torch, that doubles as an open ended microwave cavity has been used to sustain flame-like plasmas in Ar, He and N2 (S/C388, S/623, S/1221).Direct nebulisation of aqueous samples into these plasmas did not affect their stability. Workman et al. (86/C855, 86/C858) described a laminar-flow torch containing a bluff insert that was used to produce a recirculation region where the plasma is formed. The recirculating plasma was well centred and separated from the tube walls and provided increased sample residence times. It has been claimed that by achieving almost ideal matching between the generator and the cavity - plasma, a 10-W plasma can be as effective as one run at 400 W in a lossy cavity (86/C815). Sample introduction is greatly facilitated by improved plasma geometries and there have been reports of the use of nebulisation for the introduction of aqueous samples (S/849, S/1109).This may seem attractive, but the low thermal temperature (1500 K), and low thermal capacity of MIPs is not well suited to the tasks of vaporisation and atomisation andJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL. 1 135R this is reflected in poor detectability for elements forming stable oxides (S/1109). Providing the sample in vapour form is the best approach and therefore electrothermal vaporisation is more likely to produce analytically useful data (S/C758, 861C894). A graph- ite cup vaporiser in a double-walled enclosure has been described and it was found that the use of a doubled-walled container provided an order of magnitude improvement in sensitivity over a conventional single-chamber design (S1C383).Cell design was also shown to be important in using a metal filament vaporiser (86/429, 86/C490). Techniques for vapour generation for sample introduction to the MIP have been reviewed by Barnett et al. (86/C492). Among these were halogen generation, which had also been used by Abdillahi and Snook (861C495). An electrically heated quartz crucible has been employed to generate evolved gases for analysis by MIP (S/212). Applications of MIPS have included trace element determination (S/586, 86/6, 86/426, 86/1002, 86/C1249, 86/1319), the analysis of organic solutions (861C875) and of gases (86/C149, 86/C870). 2.2 -3. Chromatography The use of MIPS for gas chromatographic detection is well established and we include here only those reports that described novel developments rather than applications to particular materials.Tangential flow (91230) and laminar flow with recircula- tion (86/C999) plasma configurations, as described in the previous section, have been used as GC detectors. For the tangential flow geometry (S/1230), it was claimed that the improved plasma stability and separation from the wall provided 25-fold improvement in SNR and a reduction in wall carbonisation. A comparison of filament, tangential flow and laminar flow with recirculation plasmas reported significantly improved detection limits for the last (86/C999). The quoted limits were in the range 8-60 pg s-1 for Br, C, C1, F and H. Capacitively coupled plasmas have not been widely used because of contamination from the electrodes, but this problem has been resolved by using external electrodes to produce a transverse electric field across a quartz capillary carrying the plasma gas (86/C1152).A coaxial design in which the plasma is formed at the end of a stainless-steel capillary was described by Jansen et al. (86/122). In the same paper a point-to-plate plasma generator was employed for analysing TLC plates. A single electrode microwave plasma has been used to determine H and 0 in metals (86/1441). Most GC-MIP detectors use monochromators or small multi-channel spectrometers for spectral analysis, but Pivonka et al. (S/C263, 86/C1242) employed a Fourier transform spectrometer for the simultaneous determination of Br, C, C1, F, H, I, N, 0 and S using red and near-infrared emission lines.Noise sources in MIP optical spectra have been analysed by Goode et al. (86/C816, 86/C1156). The use of MIP detectors for empirical formula determina- tions has been discussed (S/C331, 861C1148, 861C1149). The success of this technique depends on the atomic emission being independent of the molecular form and this property can be exploited by tagging molecules, e.g., with halogens (86/103) or deuterium (86/C1153) to improve the selectivity or sensitivity of detection. An Ar MIP with an O2 sheath has been used as a detector f o r high-performance liquid chromatography (S/672). The column eluent was nebulised into the plasma and the system used to determine methyl-, ethyl- and phenyl-mercury in peat soils. The sensitivity varied depending on the compound used, but was found to be 75 ng of Hg for mercury dithizonate.2.3. Direct Current Plasmas 2.3.1. Fundamental studies The effect of easily ionised elements (EIEs) on emission from the DCP has been discussed at length and for those interested in this topic the recent paper by Miller et al. (86/105) is required reading. Studying the effect of Na on the lines of the transition metals it was concluded that: Na acts to perturb radiative transfer rather than collisional redistribution processes; population pumping of excited analyte states is largely driven by Penning ionisation ; accelerated radiative cooling due to Na is manifested in a lowering of the local kinetic temperature; to a first order of approximation, ambipolar diffusion, analyte - Na collisions of the second kind and analyte groundstate spin do not influence emission line enhancement by EIEs.Spatial maps of the electron density in the DCP showed that a thermal pinch is established in the current carrying core and that the spatial zones are very dependent on the gas flow-rates (S/C312, 861696). Electron number densities in the analytical zone were not significantly affected by easily ionisable elements or other matrix constitu- ents. Optimisation of a DCP using Simplex and factorial analysis confirmed a strong interaction between gas flows, but showed that in general no unique optimum existed, rather a ridge in the response surface provided equivalent sets of operating parameters (S/C330). Coleman et al. (S/C318) described a continuous graphite furnace atom generator, which should enable the effect of concomitant elements to be studied without the intervening processes of desolvation, vaporisation and atomisation.Noise studies by the same group showed that SNR was highly dependent on observation position with significant variations occurring on a scale of a few hundred microns (YC380, 861C857). Although interfer- ences from EIEs are well known, Fox (S11225) concluded that volatilisation interferences from A1 on Pt, Pd and Rh occurred in a DCP, but were amenable to control by using La as a releasing agent. 2.3.2. Instrumentation Sample entrainment in the DCP is not as efficient as in the ICP and in order to improve this aspect Meyer (861C493, 86/C1168) has described a new electrode configuration.Three electrodes are evenly spaced around a 60" vertical cone and a 1-mm sample injector tube is placed at the base of the vertical axis. A flame-like plasma is formed, but the sample passes through the centre exhibiting vertical zones similar to those of an ICP. The observation zone is above the apex rather than below as is normal for the DCP. The design has a similar principle to the three-electrode plasma described by Masters and Piepmeier (Y1220). A DCP has been used as a source f o r atomic fluorescence spectrometry and it was found that the plasma could be used as a narrow line or pseudo continuum source depending upon the position of the sample injector (861 1007). Sample introduction techniques for the DCP are essentially the same as those used for the ICP, although there is uncertainty as to the extent of sample penetration into the plasma.Gentry et al. (86/C860) proposed the measurement of analyte self-absorption as a means of monitoring this quantity. Apart from one report on the use of a fritted disc nebuliser (86/C1125), most of the work on nebulisation has concerned slurry nebulisation (S/C311, S/C324, S/C376, S/C472, S/851, 86/C881). A PTFE Babington nebuliser was used for the analysis of coal slurries and the effects of particle size and slurry concentration were investigated (S/C324). Fry et al. (S/C376) commented on the merits of the large diameter injector (7 mm) of the DCP for slurries. Optimisations of the DCP for slurry injection showed that the best viewing height is above the apex of the angle of the plasma, i.e., well above the normal viewing zone (S1C472, S/85l).Ebdon and Sparkes (S/C472) obtained atomisation efficiencies of 80-90% for kaolin slurries, but Derie (S/851) obtained poor atomisation for Be in beryl powder and for other refractory oxides. The nebulisation of aqueous emulsions of oils for trace element136R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 determinations (S/649) and the problems of introducing organic solvents to the DCP have been discussed (S1C381). Hydride generation for sample introduction has been described in several reports (S/C473, 86/C884, 86/1039). Coleman and Cochran (S/C355) used a narrow-bore tube (0.5 mm diameter) for injecting the hydride whereas in another report (S/C472) an Ar-sheathed injector was preferred.The following topics are of interest, but do not require detailed comments: flow injection for micro-sample introduc- tion (S1C319, S/C726, 86/C1145); direct sampling of solids by laser ablation, (S/C320, S/C1134, 861C1464); and metal sampling with a high repetition rate condensed arc (86/C1194). Additionally, a DCP has been used as a detector for liquid chromatography for the determination of phosphorus com- pounds (S/131) and with hydride generation for the deter- mination of organic tin compounds (86/ 1461). 3. FLAMES The arsenal of techniques available for analytical flame spectrometry is now approaching maturity and most of the papers reviewed this review year reflect this “coming of age.” While there were many innovative and practically useful reports, they represented “fine tuning.” Other reviews (S/C686, 86/C512), have also alluded to the maturity and acceptance of flame spectrometry.Cresser et al. (86/17) in an excellent review have critically appraised the use of shortcuts in flame spectroscopy describing practical steps at all stages of flame procedures. Herrmann and Onkelinx (86/421) have suggested a classification and unification of concepts and nomenclature of flame spectrometry for use in the field of clinical chemistry. 3.1. Fundamental Studies Gross et al. (86/C525) examined the possibility of simul- taneous multi-element analysis with optical coherent forward scattering. The instrumentation for this study combined a xenon arc lamp (XAL) continuum source with flame atomis- ation plus a diode array detector in the UV and a non- intensified vidicon detector for the visible region.While flame atomisation was chosen to give time-constant spectra, the sensitivity obtained for aqueous solutions of Cu, Mn, Ni and T1 did not approach that previously reported (see ARAAS, 1981, 11, 27). The determination of temperatures and their spatial distri- bution in flames were studied using various techniques (S/190, S/405, 86/1401). Laminar flame temperature profiles were obtained by infrared emission computed tomography (IRECT) (86/1401). Temperatures obtained using IRECT were in good agreement with thermocouple measurements. Bar-Ziv (S/405) commented on the inherent uncertainty of mapping temperatures in flames by the “Moire Effect” due to diffraction of the Moire images.Elder et al. (S/190) reported single-shot temperature measurements by laser excited atomic fluorescence spectroscopy (LAFS) in various O2 - C2H2 - Ar flames. Using an N2-pumped dye laser, temperatures in the range 2200-2465 K were determined. It was claimed that this technique gave high accuracy and precision and that it could be applied to turbulent flames. Pacheco and Bastiaans (S/C359) measured fluorescence lifetimes of directly and indirectly excited states using laser excitation. As observed fluorescence intensity shows a depen- dence on the collisional excitation and quenching processes, the lifetime measurements were used in order to calculate the over-all collisional rate constants. From these, the quantum efficiencies of the radiative transitions were computed and consequently a relationship between observed fluorescence intensity and absolute analyte concentrations was derived.Laser induced fluorescence was used to image atomic hydrogen (S/716) and hydroxyl radical concentrations (S/407) in an air - H2 diffusion flame and a pre-mixed air - C3Hs flame, respectively. In both of these studies complex laser systems were employed together with computer controlled array detectors or optical multi-channel analysers to acquire and manipulate data. Gomez and Garcia Vior (971) published a theoretically impossible account of the determination of Cs, Li and Rb using spectral superposition of lines in AAS. They suggested that the Zr 1390.052-nm line in the second order and the Cu I1 260.027-nm line in the third order could both be used for the determination of Rb at 780.023 nm.Clearly spectral order is an artifact of the dispersive element and the wavelength of the photons detected in these various orders does not change. Therefore the 780.023-nm ground-state transition in Rb could not absorb 390- or 260-nm photons. In a continuing series of theoretical papers on flame species, L’vov et al. (86/1317) showed that the decrease in sensitivity for the determination of Ir, Pt, Rh and Ru in a reducing air - C2H2 flame was related to the formation of thermally stable carbides. These workers determined the degree of dissociation of the carbides and the equilibrium constants for the dissociation reactions in the flame at 2250 K and at a fixed C to 0 ratio of 1.6 : 1.It has been suggested (S/119) that the depression of the AAS signals for Cr, Fe and Ni in a reducing air - C2H2 flame in the presence of various mineral acids can be attributed to the formation of metal carbonyls. X-ray crystallography was used to establish their presence. Hu et al. (86/C947,86/1071) studied the spatial distributions of 31 atomic, ionic and molecular species in various excitation states, arising from the alkali and alkaline earth metals in an air - C2H2 flame. They observed that the characteristics of these distributions can be related to the positions of the elements in the Periodic Table. Other reports appeared on the role of ionisation of analyte species in atomic absorption using air - C2H2 (861721) and N20 - C2H2 (86/1003) flames.On a more practical level, Takada and Satho (86/703) studied the effect of high calcium concentrations on the determination of Ba by absorption at the Ba I1 455.403-nm line in an N20 - C2H2 flame. The degree of ionisation of Ba determined from the Saha equation was three times greater than that experimen- tally observed, thus indicating that the assumptions made by these workers with respect to the effect of high calcium levels on the temperature and atomisation efficiency of the N20 - C2H2 flame were invalid. McAllister and Ham (S/C400) sampled various H2 and C2H2 flames into a quadrupole mass spectrometer in an attempt to explain the differences in atomisation of the Group IVa elements. 3.2. Interference Studies The effect of aerosol particle size on atomisation and interference processes was investigated by various workers (9132, S/1219, 86/1024).Smith and Browner (S/132) estab- lished a definite relationship between tertiary aerosol droplet size distribution and the magnitude of various well known AAS interferences ( e . g . , phosphate on Ca and silicon species on Mg). Using several nebuliser - spray chamber configur- ations in conjunction with both the air - C2H2 and N20 - C2H2 flames, they concluded that most interferences could be greatly reduced by the elimination of large droplets (>lo pm) but that this often caused a deterioration in detection power.JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 137R Pak and Hieftje (S/1219) measured the rates of vaporisation of alkali metal chloride particles in a laminar, pre-mixed air - C2H2 flame sheathed with N2 by employing a single-droplet generator (see also ARAAS, 1984, 14, 29).Solute particle vaporisation rates were determined directly by monitoring particle size with vertical position in the flame and indirectly by measuring atomic emission of atoms liberated during the volatilisation process. Long and Boss (86/1024) studied the effect of droplet size on the phosphine depression of Ca atomic emission in an air - C2H2 flame. They suggested that this interference could be alleviated by using a glass-frit nebuliser or by removing droplets greater than 2 pm in diameter. Newman et al. (SIC352) have surveyed the effect of phosphine on 60 elements routinely determined by atomic spectrometry in both air - C2H2 and N20 - C2H2 flames.The effect of phosphine on Ba, Ca and Sr was previously identified by Long and Boss (see ARAAS, 1982,12,29 and 1983,13,25). Of the elements that form refractories with Po43- only Ti and Zr showed a phosphine depression. The phosphine depres- sion, when observed, was found to be consistently lower for AAS than AES, which reflected the different regions of the flame utilised for these types of measurements. Abdallah and co-workers ( ~ 4 9 1 , S/508, 86/1028, 860029) reported a considerable amount of work on the characterisa- tion and elimination of interferences in an air - C2H2 flame using the continuous titration technique (see also A RAAS, 1978, 8, 19). They showed (S/491) that the effects of an extensive series of anions, cations and complexing agents (either singly or mixed) on a signal from a 10-3 M solution of Cr(II1) could be eliminated by addition of either boric acid (1.85 X 10-2 M), sulphosalicylic acid (2.0 x 10-2 M) or KCN (5.0 X M).Similar measurements with a 3.6 X M solution of Fe(II1) suggested that interferences could be eliminated with either sulphosalicylic acid or 4-aminosulpho- salicylic acid (2.0 x 10-2 M). In a recent study this group employed cyanide to counter the interference from organic ligands on Cd, Cu and Zn (86/1028). They also reported the characterisation of interference effects in the determination of Mo arising from the formation of iso- and heteropoly anions and spinels (8611029). Other workers, without success, attempted to use the formation of phosphomolybdic acid to improve the analytical performance of Mo determination (86/804). Readers interested in the study of interferences using the continuous titration technique should also consult ref.86/1448. A number of conference reports (86/C128, 86/C575, 86/ C579) have described the systematic examination of the mechanisms of releasing agents used in atomic spectrometry. Kantor (86/C128) suggested that only lanthanum chloride could be used as a releasing agent for the determination of Ca in the presence of aluminium or phosphate in the air - C2H2 flame, as lanthanum nitrate enhanced the interference. Stojanovic et al. (86/C575) employed the continuous titration technique to examine the effectiveness of calcium, lanthanum, praseody- mium and strontium chlorides as releasing agents for removing the interference of silicates on the determination of Mg in an air - H2 flame.They established that the order of effectiveness was Ca > Sr > La > Pr. Urbain (86/C579) reviewed and classified the usage and types of buffers and releasing agents used in the flame spectroscopic determination of major, minor and trace constituents in catalysts. Readers interested in the use of releasing agents may wish to consult the following references: S/884,86/245,86/C273,86/C296,86/C586,86/1283. Fan and Zhu (S/34) reported the use of an emulsion, formed with the aid of a surfactant as a concentrating agent for the AAS determination of Mo(V1) in the presence of high levels of chromium. Zhanxia et al. (S/C675) investigated parameters such as surface tension, flame chemistry, ionic distribution and lateral diffusion to model the mechanism of the enhance- ment and suppressing effects of various surfactants on AAS determinations.These workers used surfactants to eliminate interferences from concomitant elements on the determi- nation of Cr in electroplating waste solutions. A number of other applications of surfactants have appeared (86/77, 86/C274, 86/1030). 3.3. Instrumentation Ogasawara et al. (861C509) described a new burner configura- tion that utilised four concentric Pyrex tubes to support either normal or inverted hydrogen flames and those intermediate between the two. They exploited the poor atomisation efficiency of the hydrogen flame to determine trace levels of Ba in the presence of calcium by monitoring the BaOH molecular emission at 487 and 512 nm, thereby avoiding CaOH interference at 553-557 nm, which overlaps the Ba atomic resonance line.Lowe and Sutton (86/216) obtained performance charac- teristics for their flowing vapour capillary discharge lamp (CDL) comparable to those of standard HCLs for the determination of As, P, S and Se by AAS in a variety of flames. In this study they have expanded upon their original work with an iodine CDL (see also ARAAS, 1982,12,27) and also suggest that the CDL source may be suitable for AFS. Developments in the use of flames for continuum source multi-element FAAS have been few in this review period, although associated modifications of instrumentation and applications continue to appear (S/347, S/575, 861204, 861306, 86/676).The successful determination of a range of elements of different atomisation characteristics requires the adoption of compromise atomisation conditions, which involves a difficult choice between air - C2H2 and N 2 0 - C2H2 flames. Miller-Ihli (86/1087) has attempted to overcome this problem by the use of an N 2 0 enriched air - C2H2 flame. The increase in flame temperature obtained by the addition of N20 to an air - C2H2 flame ensured satisfactory dissociation of Ca and Mg compounds, and allowed the accurate analysis of several NBS SRMs for Ca, Cu, Fe, K, Mg, Mn, Na and Zn on a simul- taneous basis with addition of caesium only as an ionisation suppressant. Calibration over 5-6 orders of concentration in continuum source AAS is achieved by absorbance measure- ments in the wings of the line profile.An extensive study of curve fitting procedures for extended range AAS has been reported by Miller-Ihli et al. (S/626). Methods evaluated included linear, quadratic and rational least-squares fit, linear and cubic splines and Stineman interpolations. The concen- tration ranges providing minimum relative concentration precision were identified and shown to be coincident with minimum curve fitting errors. The log - log slopes were generally 0.5 indicating that linearity is not the only criterion for choosing the optimum calibration and curve fitting concentration ranges. Using air - C2H2 flame atomisation, Messman et al. (S/575) compared the analytical characteristics of a direct current plasma, which they termed a pseudo-continuum source, with those of a xenon arc lamp (XAL).Solutions of high analyte concentration were aspirated in the DCP to broaden deliber- ately the line emission over the narrow wavelength modul- ation interval. While the stray radiation characteristics of the DCP where superior to those of the XAL, the intensity of absorbable radiation and SNR were degraded by self reversal and flicker, respectively. This was reflected in the detection limits of the two elements studied (Mg and Zn), which were at least an order of magnitude poorer using the DCP source. Pleban et al. (S/C310) compared, on the basis of sensitivity, precision and accuracy, the use of Zeeman effect and Smith - Hieftje background correction systems for the determination of Cd, Pb and Zn using an air - C2H2 flame.The Smith - Hieftje system produced better sensitivity and the Zeeman effect gave superior analytical precision for the three test elements. They reported that comparable accuracy was138R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 obtained for Pb and Zn using either system, but that the accuracy of Cd determinations was poorer using the Smith - Hieftje system due to a marked non-linearity of the calibration curve. Other workers have also reported the use of the Smith - Hieftje system (S/584, 86/C839) and the Zeeman technique (S/627, S1628, 8611088, 86/1292) for background correction in FAAS. It would appear that both of these techniques in conjunction with FAAS will find more general usage in the future.Bakarat et al. (86/C577) presented a theoretical discussion on the effect of background interferences in flame AAS in terms of line profiles and coincidences. Boss and Pearce (86/C873) suggested that electrostatic aerosol modula- tion (EAM) could be used for background correction in flame spectrometry. Using EAM coupled with cross-correlation or lock-in amplification, interference from OH bands was removed in the determination of Bi and Mg. As with other flame techniques only minor developments in atomic fluorescence spectrometry have been reported. Naran- jit et al. (S/654) described a microcomputer-controlled, ten-channel non-dispersive AF instrument. This used radio- frequency EDL line radiation sources and-an air - c2H2 atom cell. The detection limits obtained were comparable to ICP-AES and ICP-AFS.A xenon arc continuum source dispersive AFS system with an Ar separated air - C2H2 flame and a microcomputer controlled slew-scan monochromator has been described by David et al. (86/1356). Other workers (86/87) compared the O2 - C2H2 - He and air - C2H2 flames for continuum source AFS atom cells. Their study showed marked superiority for the O2 - C2H2 - He flame in terms of detection capability, but this flame gave a much higher background in the 185-650 nm range. Wu and Michel (86/1415) examined spectral interference and stray light problems in dispersive FAFS using both xenon arc continuum and radiofrequency EDL sources. 3.4. C hemometrics During the past year a number of reports have appeared (S/626, S/1089, 86/C150, 86/239,86/325) that were concerned with expressions for fitting calibration data particularly for extending AAS calibration ranges.Kleij burg and Pijpers (S/1089) have postulated a correlation between non-linearity of calibration curves and wavelength via Rayleigh scattering. de Galan et al. (86/325) evaluated an extensive selection of mathematical expressions for their ability to fit highly curved calibration graphs. They suggested that the non-linear portion of the curve offered reliable analytical results provided that it could be accurately described. It was also found that hand drawn or computer calculated calibration graphs agreed within 1% provided that 5-8 data points were used and that weighting factors were applied to the least squares fit. Other workers (86/C150, 86/239) have studied the usefulness of calibration algorithms written into the commercial software of AA instruments.Further reports of calibration studies may be found in refs. S/379, S/602, S/619. Koscielniak and Parczewski (S/498) used segmented poly- nomials in an approximation approach to the modelling of interferences encountered during AAS determinations of Ca and Fe in the presence of strontium and sodium, respectively. In both instances, the split polynomials more accurately correlated with the experimentally observed interferences than with single high degree expressions. It has been reported (S/C534) that correlation functions could be used for semi- quantitative standardless AA analysis using a variety of flame and spectroscopic parameters. Improvements to the accuracy and precision of flame spectroscopy were investigated by employing Simplex optimi- sation (S/97,86/23) and internal standardisation (S/46, S/C533, 86/1008).Both of these topics have been discussed previously in ARAAS (see, for example, ARAAS, 1978, 8, 68 and ARAAS, 1971, 1, 52). Rohon et al. (86/C585) presented a novel optimisation algorithm that was designed to illustrate the markedly different Pb sensitivities attained for five organolead compounds in FAAS. These workers suggested that owing to the significant variations in optimum instrumen- tal parameters with each organometallic compound, elemen- tal speciation may be possible. 3.5. Sample Introduction The major innovative studies and applications in this area have been concerned with atom trapping, discrete nebulisa- tion, flow injection and chromatographic techniques.These are examples of the “fine tuning” of flame spectrometry which the maturity of the technique now requires. The section on nebulisers covers those papers related specifically to flames, but interested readers should also consult section 2.1.2 as much current research on nebuliser design and performance, although relevant to flame operation, is aimed at their use in the ICP field. 3.5.1. Nebulisers and spray chambers Sturman (S/C357, S/C694, 86/C836) described an improved pneumatic nebuliser for AAS. This device was claimed to have superior liquid transport characteristics due to maximised suction, which in turn gave rise to the capability of handling higher concentrations of dissolved solids than previous confi- gurations.Cordos et al. (S/25) constructed a variable capillary nebuliser for operation with air - CH4 or 0 2 - CH4 - air flames. These workers also carried out photographic droplet size distribution measurements. Robinson and Wu (86/670) evalu- ated a titanium ultrasonic nebuliser, which gave performance characteristics superior to a concentric nebuliser, but inferior to an aluminium ultrasonic device previously described (Spectrosc. Lett., 1984, 17, 653). The titanium nebuliser may find application in the field of HPLC-AAS due to its low dead volume. An interesting application of branched capillary nebulisa- tion (see ARAAS, 1984, 14, 32) was reported by Grases and March (S/87, 9902). These workers attached a bifurcated capillary to a conventional AAS nebuliser in order to determine indirectly P and Si (S/87) and Ti (S/902).Their technique was based on the interference that the three analyte elements caused to a Ca signal. Through one branch of the capillary a 50 pg ml-1 Ca solution was aspirated and the resultant AAS signal monitored. Samples and standards containing the analytes were introduced via the second capillary and the depression of the Ca signal was used to determine the analyte concentration. Hoffman (86/C280) suggested that the double capillary technique could be utilised for the evaluation of chemical interferences in both the AAS and AES determinations of the rare earths. From the reports received over the past review year it appears that slurry nebulisation for flame spectrometry was restricted to applications where atomisation was not of prime importance, the matrix was easily destroyed or extremely small particle sizes were used. Wichman et al.(S/C298) showed that Ca (residual bone) determinations on acidified - homogenised meat slurries could be accomplished. These workers measured the molecular emission from CaOH at 622.5 nm in preference to atomic emission. Calibration was found to be accurate with aqueous standards without using standard additions in both the air - C2H2 and N 2 0 - C2H2 flames. Lakatos et al. (86K275, 86/C508) investigated the problems associated with the introduction of slurries into the flames. They concluded that even at a particle size below 1 pm, atomisation efficiency would be severely affected if the sample was difficult to volatilise.Mass transport losses were identified as a major contributing factor in the decreasedJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 139R FAAS signal for a coal slurry compared with aqueous standards, by Mohamed et al. (86/1432). Discrete sample nebulisation has continued to find appli- cations in the analysis of real samples over the past review year. Ekanem (S/7) utilised discrete nebulisation for the introduction of 200-p1 samples into a nitrogen-separated air - C2H2 flame. The technique was used for the determination of Cd, Fe, Mg and Zn by AFS, Na by AES and P by molecular fluorescence spectroscopy in blood, serum and urine. A detailed account of the optimisation procedures, instrumenta- tion and signal retrieval system was given.Other clinical applications of discrete nebulisation were reported by Liska et al. (861956, 86/1292). These workers compared both continu- ous and discrete nebulisation for the determination of Cu and Zn in blood, plasma and serum using Zeeman effect FAAS. Their results suggested that the latter nebulisation technique was superior for these sample matrices. Discrete nebulisation coupled with AAS was suggested (86/253,86/339,86/685) as a means of minimising interferences from high dissolved solids. Batistoni et al. (86/685) determined Cd, Cu, Mn, Ni and Pb in nuclear grade zirconium alloy solutions (10% m/V) and achieved acceptable accuracy compared to NBS standard reference materials. A novel application was reported by Kojima et al.(86/666), who measured the absolute mass of Cu and Mn in small samples (1-10 mg) of NBS standard reference materials. The samples were digested in 200 pl of an acid mixture using a PTFE bomb. The total volume of digested material was then introduced to a flame atomic absorption spectrometer via discrete nebulisation. The results obtained in this manner were in good agreement with NBS certified values. O’Grady et al. (86/C144) investigated the use of variable position impactor beads or cups in spray chambers and showed that by varying the distance of the impactor from the nebuliser capillary tip, 25-fold reduction or a two-fold enhancement of signals could be obtained. This variation of analytical signal was used to extend the linear working concentration range and to control interferences.They also studied the patterns and causes of deposition losses in a simple spray chamber with lithium and smoke tracer experiments (861203). Ham and Willis (86/C576) also studied the effect of impact bead position together with spray-chamber design with a view to limiting interferences. Cresser (86/333) discussed the problems asso- ciated with the routine usage of pneumatic nebulisers and assessed the possibilities for improvements in useful transport efficiency. Willis(86/C539) outlined several distinct processes that affect aerosols between the nebuliser and the flame. These processes were discussed in relation to the relative merits of different nebulisers, nebulisation efficiency, drop size distribution, theoretical models and experimental results.3.5.2. Atom-trapping techniques This technique has attracted considerable interest over the past review year and therefore it is appropriate to outline the two main types of atom trapping used to enhance the sensitivity of conventional FAAS. The first technique, initially reported by Held et al. (see A R A A S , 1975, 5 , 12), used a water-cooled tube positioned above the burner. The analyte was condensed on to the cold silica surface via continuous nebulisation into the spray chamber - burner system for a predetermined length of time. The water was then blown out and the quartz capillary tube rapidly heated, vaporising analyte atoms into the light path. The second type was first described by Watling (see A R A A S , 1977, 7, 24) and consisted of a dual-slotted tube mounted directly above the burner, which directed the flame into the bottom slot and out the top.This technique, rather than actually trapping atoms, lowered their velocity through the measuring zone and thus increased the analytical sensitiv- ity. Brown and co-workers (86/C580) gave an informative conference presentation that discussed the operational aspects of both types of atom-trapping together with their inherent advantages and disadvantages. They concluded that both methods facilitated sensitivity improvements compared with conventional FAAS for volatile elements. Hallam and Thompson (S/917) have now published their study on the use of single and dual water-cooled atom-trapping devices (see also A R A A S , 1984, 14, 33).They compared analytical figures of merit for various tube coatings that were applied in situ by continuous nebulisation of Al, La and V solutions on to the silica surface. Good agreement for Cd and Pb determinations in potable water samples using either ETA-AAS or the atom-trapping procedure was obtained. In this work basic performance characteristics for Ag, As, Cu and Se were also presented. Risova et al. (86/C584) showed that Cd, Pb and Zn could be determined in diluted high purity acids at levels ranging from 20 to 1400 yg 1-1. These workers used a single, uncoated tube and 10-min collection periods. Sun et al. (860304) claimed two orders of magnitude improvement in sensitivity for the determination of Ag using a cooled atom trap. Brown et al.(S/893, S/918,86/193) illustrated the usefulness of a commercially available slotted tube atom-trapping acces- sory for real sample analysis. They used it in conjunction with discrete nebulisation of 200-y1 aliquots for the determination of Pb in beer at concentrations below 100 pg 1-1 (S/893). Other applications (S/918,86/193) included the determination of Cd, Cu, Pb and Zn in water, urine, whole blood and serum using both continuous and discrete nebulisation. Also reported (86/193) was the in situ coating of the atom trap with lanthanum to retard devitrification of the quartz. Keil (Si179) suggested that the sensitivity for 25 elements was enhanced by factors ranging from 1.2 to 30. The greatest enhancements, compared with conventional FAAS were observed for the more volatile elements, viz.Sn ( x ~ O ) , As ( ~ 1 3 ) , Hg (X12), Bi ( ~ 1 2 ) , Zn ( x l l ) , Ag ( x l l ) , Pb ( x l l ) , Cd (XlO) and Sb (x9)- 3.5.3. Flow injection techniques Once again, considerable effort has been devoted to flow injection (FI) techniques. The popularity and versatility of FI-AAS was reflected in the three review papers of Gallego et al. (S/840) and Tyson et al. (86/200,86/365), which discussed a variety of instrumental configurations, calibration procedures and analytical techniques including ion-exchange and solvent extraction. Fang et al. (S/629, S/651) reported the use of on-line ion-exchange columns for analyte pre-concentration. The determination of trace concentrations of Cd, Cu, Ni, Pb and Zn in sea water was accomplished using several chelating exchange resins.Their choice of resin was based upon its ability to minimise interferences experienced in sea-water analysis. Ion-exchange FI-AAS was applied to the determi- nation of free and EDTA-complexed Cu(I1) (86/37) and to Cu, Mn and Pb in soldering fumes (86/1316). An interesting method of on-line pre-concentration was reported (S/631) that used FI for sample pre-treatment followed by a silica-immobi- lised 8-hydroxyquinoline extraction column prior to FAAS detection of Cu. The most attractive feature of this system was that the immobilised reagent resulted in a greatly simplified FI manifold. The system was employed for Cu determinations on EPA water samples and good agreement was achieved between the measured and reported concentrations.More conventional sample pre-concentration was reported that used solvent extraction - FI-AAS to quantify trace amounts of Zn in an iron matrix (9579). A novel FI-AAS technique employed a CuS packed column to convert CN- ions into Cu(CN)& for the indirect determi- nation of CN- (86/1382). While the reported sensitivity was not remarkable, it may motivate other workers to utilise more chemistry to obtain an improved detection capability. The indirect determination of U with FI-AAS by monitoring the effect of U on an Fe signal has been described (86/90). The FI140R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 system in this particular application was functioning as an expensive bifurcated capillary nebuliser (see section 3.5.1).The technique was also subject to severe interferences and these workers could have put the FI apparatus to better use, for example for separation and pre-concentration of the analyte. Calibration strategies for FI flame spectrometry have been of interest over the past year. Tyson and Appleton (Sh308) constructed AAS calibration curves by aspirating a single standard that was continuously diluted using FI. Their system was simple and produced continuous calibration functions that did not require the use of curve fitting algorithms. Sherwood et al. (86/1459) employed a similar calibration routine for the determination of Ca, Cu, Li, Mg and Zn in body fluids by FI-AAS. The determination of Ca, Li, K and Na in solid extracts and tap water by FI-AES has been reported (M114).In this method, the analyte emissions were measured by means of a rapid-scanning monochromator and storage oscilloscope. Calibration was achieved using multi-element standard additions with continuous FI dilution. Memory effects were reduced by an order of magnitude, compared with those observed in FI-AAS using conventional injectors and high elemental concentrations, by a new three pump, two valve injector (86/306). Further information on applications of FI to flame atomic spectrometry is contained in the following references S/358, S/C535 and 86/89. 3.5.4. Sample introduction by volatilisation Relatively little work on direct micro-sample introduction appeared during the past year. Bye (9826) once again determined Se by electrodeposition on to a platinum loop followed by simultaneous electrothermal and H2 - Ar flame atomisation (see also ARAAS, 1981, 11, 30).This technique has been used for interference studies (86/C582) and the determination of Zn in cerebrospinal fluid (86/C583). The use of a microsampling cup was reported (86/C761) for the determination of Pb in vegetable matter that had been ashed prior to the insertion of the cup into the flame. Berndt and Tristao (86/C578) employed a volatilisation procedure (see A R A A S , 1984, 14, 35), which utilised an electrothermal vaporiser coupled directly to a quartz tube positioned in an air - C2Hz flame. Samples were placed on the vaporiser and then desolvated and ashed by an external tungsten - halogen lamp prior to being vaporised and swept into the atomisation cell.van Wagenen and Fernando (86/1379) described a modified spinning sample cup for S2 molecular emission cavity analysis (MECA). The expected improvements in precision were not realised through the modification discussed. Sakai et al. (86/347) determined traces of As in evolved gases from NBS oyster tissue using Zeeman effect AAS at the 193.696-nm line using a reducing air - C2H2 flame. 3.5.5. Chromatographic detection Techniques coupling chromatography with flame spec- trometry have been used successfully for over a decade (see ARAAS, 1976,6,19) particularly in the area of environmental analysis (see J. Anal. At. Spectrom., 1986, 1, 1R). The most important facet of this topic is the interface efficiency. Over the past review year no new GC-AAS interfaces were reported, although some advances were made in HPLC-AAS coupling techniques.Most papers in the GC-AAS area were concerned with improvements to sample collection and pre-treatment. Harrison and co-workers illustrated the usefulness of the above technique in two review articles (S/612, S/890), and also reported their experiences with GC-AAS for the determi- nation of organometallic compounds in the atmosphere (9911, 91199). The instrumentation utilised porous polymer collection of ambient air for from 3 to 24 h periods prior to thermal desorption on to the GC-AAS system (9911). Chakraborti et al. (S/115) determined ionic alkyllead com- pounds in water by pre-treating samples with n-butyl Grignard reagent after solvent extraction. The butylated lead species could then be quantified by GC-AAS.Ohta et al. (86/1068) reported the application of high temperature GC-AAS (column temperature >1500 K) to the determination of Cu in sea water. Their method resulted in a characteristic mass of 0.8 ng of Cu. Wu and Robinson (S/C353) evaluated two ultrasonic nebulisers (861670) for their suitability as low dead volume HPLC-AAS interfaces. Ebdon et al. (Si919) reported a simple and effective HPLC-AAS interface that utilised discrete nebulisation and the slotted tube atom trap. Using this instrumentation they determined various Sn species in local harbour waters. Katz and Scott (86/70) examined the disper- sion characteristics of liquid chromatographs used in conjunc- tion with AA spectrometers and consequently recommended the use of a serpentine tube as a means of interfacing the two.Hill et al. (861C142) critically assessed the performances of three HPLC-AAS interface configurations on the basis of Sn speciation results in sea water. One of the techniques has been described above (S/919), the others involved ( i ) continuous hydride generation with on-line UV degradation of non- reducible Sn species and (ii) metallic filaments to transport HPLC eluent directly into the flame in order to eliminate nebulisation losses. Flame AAS as a specific detector for ion-exchange chro- matography has received some interest. Suzuki et al. (S/6) separated metallothioneins with on-line switching gel- permeation to ion-exchange columns, the metals bound to the isoproteins then being directly detected by FAAS. Aihara et al.(86/419) suggested the use of ligand exchange chro- matography for the indirect determination of glycylglycine by monitoring Cu in the eluent. 3.6. Applications of Lasers Traditionally, this section in A R A A S covered the developing use of lasers for analytical measurements in flames. In recent years, however, it was expanded to reflect the increasing interest in atomic fluorescence and diagnostic measurements in plasmas and electrothermal atomisation systems, which have significant advantages when made with laser excitation. This format is being continued in this first review of “Atomisation and Excitation” in J A A S , although important diagnostic papers will also be covered in relevant individual sections (see section 2.1.1, for example).The flame remains the most common atomisation device for both laser atomic fluorescence (LAFS) and laser-enhanced ionisation (LEI) studies, but the trend towards the use of ICPs and graphite furnaces, noted in recent years (see A R A A S , 1983,13,34 and A R A A S , 1984,14,37) continues. The review period has been an active one in all the topics highlighted in this section. The reviewer noted, in particular, several interesting instrumental developments, including a proposal to extend the range of excitation wavelengths available to LAFS by anti-Stokes Raman-shifting (86/C527). Two reviews have appeared (S/898, 86/708), one dealing with the use of diagnostic techniques, including LAFS and LEI for measure- ments in low-pressure plasmas of the type used in microelec- tronics materials processing (86/708).Although the number of groups demonstrating sensitive LAFS and LEI measurements is increasing steadily, the commercial development of these techniques appears no nearer. Some of the limitations implicit in the operation of lasers as excitation sources were recently discussed by Hieftje (J. Anal. At. Spectrom., 1986, 1, 4), who suggested that dramatic developments in laser technology would be required to make commercial development of analytical instruments viable. This area remains, however, one of the most fascinating and fundamentally productive areas of atomic excitation.JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 141R 3.6.1. Laser-excited atomic fluorescence spectrometry ( L A FS) Apart from the increasing use of laser atomic fluorescence spectrometry for diagnostic purposes and with electrothermal atomisers, the highlights of this review period lie in a number of interesting and potentially useful instrumental develop- ments.A new LAFS instrument with two excitation beams, a measuring beam and a reference beam delayed by a few ns, has been described in a patent (S/235). The analytical characteristics of Nd : YAG laser-pumped and Cu vapour laser-pumped dye lasers have been compared with a flash lamp-pumped dye laser (86lC915). Non-resonance transitions of Fe and Ni were measured in an Ar-separated air - C2H2 flame, and it was observed that detection limits with the Cu-vapour laser were similar to the flashlamp-pumped dye laser, which were both two orders better than the Nd : YAG laser.Differences were explained on the basis of the dominant noise sources in each system. An interesting paper by Quentmeier and Laqua (86/C527), proposed an extension of the UV-range available to LAFS by means of anti-Stokes Raman-shifting of radiation from an excimer laser-pumped dye laser, using a Raman cell filled with hydrogen. Employing coumarin 2 as the laser dye, the first six anti-Stokes orders give radiation in the range 400-210 nm of decreasing intensity with decreasing wavelength. Each of the Raman-shifted components can be tuned by tuning the dye laser. At present, the Raman conversion is less efficient than frequency doubling using KDP or KPB crystals, particularly at the higher Raman orders, but several possibilities were described for improving the spectral radiance at short wavelengths.Potentially, this technique could open-up the use of low UV wavelengths not currently reached by fre- quency doubling. In a number of conference presentations, Omenetto (86K483, 861C1245) and Omenetto and Rossi (86K125) described some new experimental configurations developed by the Ispra research group. Two pulsed, tunable dye lasers, simultaneously pumped by an excimer laser have been used selectively to populate excited levels of both atoms and ions in an air - C2H2 flame and an ICP. Measurements of fluorescence and LEI signals resulting from the collisional ionisation of highly excited atoms were obtained in the flame, and only ionic fluorescence in the ICP. With two photon excitation, if a highly excited level is reached in the second step the quantum efficiency of atomic fluorescence is poor, due to population depletion by collisionally assisted ionisation.Techniques based on two-photon excitation fluorescence offer high spectral selectivity and sensitivity, and a unique method of correction for scattered radiation. The most efficient exploita- tion of the technique was in ionic fluorescence in the ICP. Use of a third laser, temporally coincident with the two dye lasers has been used to excite ionic fluorescence in an air - C2H2 flame (86lC1245). Michel and co-workers have now published their work on the gated operation of photomultiplier tubes for LAFS signal detection (S/841, S/C1152, see also A R A A S , 1984, 14, ref. C1075). The PMT is switched off for more than 99.9% of the time, and is gated to operate during the period of the pulsed LAFS signal.Detection limits and SNR were improved in both flames and the direct current plasma (DCP) by use of large monochromator slits that would otherwise have led to PMT saturation and non-linearity of the calibration graphs. Reduction of flame background is clearly essential to improve SNR in LAFS, but background correction will also be essential for the practical application of this technique. Further experimentation on the use of the Zeeman effect for back- ground correction in LAFS has been presented (86/C878), and Hart et al. (86/1102) have given theoretical derivations of the background correction technique based on sine-wave or square-wave intermodulated atomic fluorescence spectro- scopy (see A R A A S , 1984.14, 37). At high irradiances, the fluorescence signals reach a plateau in square-wave modula- tion, but exhibit a roll-over effect under sine-wave modula- tion, the scatter signals having zero intermodulation corn- ponent . The theoretical predictions were verified experimen- tally for Na in an Ar - O2 - H2 flame using a square-wave intermodulated CW dye-laser system. Several groups have continued to exploit the sensitivity of electrothermal atomisation to improve the detection limits achieved by LAFS (86/C528, 86/C529, 86/C877, 86/C878, 86/C916, 86K990). The problem implicit in combining ETA with LAFS lies with current furnace or tube systems employed in ETA, which place physical limitations on the measurement of LAFS in the preferred arrangement of a 90” angle between excitation and fluorescence light beams.Michel has described the use of a graphite tube furnace with Zeeman-effect background correction (86/C878, 86/990) and the require- ments for tube design, optical minimisation of background emission and sample introduction in such a system were presented (86/C877). Dittrich and Stark (86/C529) described a graphite tube furnace designed specifically for LAFS measurements. Radiation from a dye-laser system was transmitted through slots cut in the sides of the graphite tube, and fluorescence was monitored through the open ends of the furnace. Improvements in sensitivity between 7 and 1240 were obtained for six elements of varying volatility compared with carbon-rod atomisation.The tube system also gave improved reproducibility and greatly reduced matrix interferences. The main reason for the substantially improved performance of the tube furnace atomiser was said to be the more homogeneous temperature distribution within the observation zone. A tungsten-spiral atomiser has also been described for LAFS measurements, but the results presented most recently were limited to use with EDLs as the light source (86K528). A number of interesting applications of LAFS have been reported (86/C524, 86/1282, 86/1372, 86/1424). Improved detection of Au, Ir, Pd, Pt and Ru in an air - C2H2 flame were achieved by using a large aperture detection system and a frequency-doubled pulsed, tunable, dye laser for excitation of non-resonance atomic fluorescence (86/1282).Detection limits at the ng ml-1 level or less were superior to FAAS and FAES, but comparable to ICP-AES. Bol’shov et al. (8611424) described the application of their electrothermal atomiser system (see A R A A S , 1982, 12, 34) to the determination of a wide range of elements in agricultural samples including soils, crops and animal feeds. Both these workers, and Tilch et al. (86/C524), have been concerned with the direct determination of trace elements in solid samples. In this instance, a “pot,” i.e., cup atomiser, is most convenient and the combination of ETA-LAFS provides a means of removing the bulk of the matrix by pre-ashing. In the current review period, Tilch et al. (86IC524) described the application of their nitrogen laser-pumped dye laser system (see A R A A S , 1983,13,34) for the determination of ng g-1 levels of Ir, Pd and Rh in solid samples of photographic films.Michel et al. (S/C1152) have continued their studies of LAFS in a direct current plasma. The enhancement effects of easily ionised elements that are observed in AES studies were also observed in LAFS, but a LAFS study of Ca I showed that the enhancements were not related to variations in atom density. The enhancement of fluorescence signals at low laser powers disappeared at laser powers sufficient to saturate the atomic transitions, indicating that a collisional energy transfer mechanism is responsible for the enhancement, and that the DCP is not in LTE (see section 2.3). Further studies have been reported on the use of a glow discharge lamp as an atom source for LAFS (86/1392).Observations, using LAFS, of the material sputtered from a cathode containing lead, revealed the presence of molecular species identified as Pb2 from the molecular band spectra generated at the same time as the Pb LAFS signal. It is suggested that molecular emission spectral interferences should be considered whenever a GDL is used as an atomisation cell for analytical purposes.142R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 The use of laser induced fluorescence of both atomic and molecular species for diagnostic purposes in flames, ICPs and combustion processes continues to receive considerable atten- tion (S/407, S/716, S/C1129, 86/704, 86/706, 86/1402, see also section 2.1.1).Measurements of molecular species such as OH (S/407, 86/706) and CH (86/1402) are now increasingly common, and profiling in flame systems has been achieved either laterally by movement of the burner with respect to the laser beam (86/706), or vertically by using a single laser sheet and an optical multichannel analyser for data acquisition (S/407). A three-dimensional image of the distribution of H atoms in a laminar air - H2 diffusion flame has been established using two-photon excitation (S/716) in a manner similar to that reported previously for 0 atoms (see A R A A S , 1984, 14,38). Laser radiation at 243 nm was used to excite the 1s to 2s transition of H, from which it was raised to the 3p state by a second laser tuned to 656 nm. The Balmer series transition at 656 nm was then observed by a linear array detector after passing through a 656 nm interference filter.A sequence of linear images across the flame was used to construct a three-dimensional picture. The comparison of 0 and H profiles provided by this technique is likely to be very useful in combustion diagnostics. A single-shot measurement procedure has been developed for the determination of flame temperatures by thermally assisted atomic fluorescence spec- trometry (S/190). Three Ar - 0 2 - C2H2 flames were found to have temperatures ranging from 2200 to 2465 K. The single-shot result were of high accuracy and precision. A number of approaches to the determination of fluorescence lifetimes in flames have been suggested by Pacheco and Bastiaans (S/C359).In one , a pulsed dye laser output was split into probe and saturating beams, which were crossed in the atomic vapour. By delaying the probe beam, a cross-correla- tion between the excitation process and the delayed detection of the excited state can be obtained. The cross-correlation directly indicates the lifetime from the decay function of the excited states. 3.6.2. Laser-enhanced ionisation (LEI) Although initial experiments in laser-enhanced ionisation (LEI) were carried out with single-photon laser excitation followed by collisionally assisted ionisation (see A R A A S , 1978,8,23), it was rapidly realised that the use of two photons to populate highly excited atomic levels would significantly improve the sensitivity and selectivity of the detection of most elements, and this has now been demonstrated theoretically (861C914).In the review period, the two-photon excitation process has been used in some interesting fundamental studies in flames. Using a system in which two tunable dye lasers were simultaneously pumped by a single excimer laser, ionisation yields as high as 50% have been observed in air - C2H2 flames, and detection limits for several elements including T1 were in the pg ml-1 range (S/1099, 86/C914). If the laser irradiance is very high (ca. 100 MW mm-z), several two-photon transitions are observed and the resulting spectrum may be complex and difficult to interpret, affecting both sensitivity and spectral selectivity (86/C914). In another study, two-step excitation of LEI signals was used to evaluate the collisional lifetimes of the metastable 2P3,2 levels of Pb and T1 (861214).Measurements were made in an air - C2H2 flame with two excimer laser pumped dye-laser systems triggered to operate with a time delay between them. The second laser photon, tuned to a transition starting from the metastable level under study, was delayed from the first photon, tuned at a transition starting from the ground state. As the delay time is increased, the LEI signal decreases due to collisional depopulation of the metastable level. The lifetimes were 81 ns for T1 and 360 ns for Pb, and the delay time range used was correspondingly chosen between 0 and 150 ns for T1 and 0 and 1500 ns for Pb. Scanning both laser wavelengths in a two-step excitation process can be used to produce a three-dimensional wave- length map of the LEI spectrum (86/C589).Turk et al. (86/C589) reported an investigation using a Nd : YAG laser to pump two dye lasers centred at the sequential Ba transitions excited by radiation at 553.5 and 494.7 nm. This scheme populates a level that is only 3768 cm-1 below the ionisation limit. The contour plot of Ba in an air - C2H2 flame, produced by scanning the wavelength of both lasers, indicated a peak width considerably broader than the laser band width of 0.01 nm caused by saturation broadening. Three ridged features at low LEI signal levels were observed. Two represent the effects of single-step excitation, while the third is derived from off wavelength combinations of the two lasers, which, when combined, give the energy of the upper level from which collisional ionisation occurs.Desolvation of discrete sample volumes, either by passing through a microcondenser, or a standard graphite furnace, has been combined with a total consumption burner to achieve considerably improved LEI detection limits (S/576). The best experimental detection limit reported for Mn was 0.2 ng ml-1. Whilst the microcondenser was inexpensive to construct and operate and is more convenient for elements that form stable carbides, the graphite furnace allows the atomisation of samples to be separated from the ionisation process in the flame, and would potentially allow the use of an air - H2 flame to suppress electrical interferences. Detection limits in the ng ml-1 region have also been reported for the LEI measurement of refractory elements in an N20 - C2H2 flame using a water-cooled electrode immersed in the flame (86/ 215).Typical values such as A1 0.2 ng ml-1, Mo 10 ng ml-1, Ti 1.0 ng ml-1 and V 0.9 ng ml-1 indicate that LEI, using this flame, offers comparable sensitivity to other spectroscopic techniques for these elements. A number of interesting applications studies have appeared during the review period including two separate studies of Na in the Chinese literature (S/130, 86/377), which indicate the increasing world wide interest in LEI. Low detection limits have been achieved by a Swedish group using one-step LEI in an air - C2H2 flame (9636, 86/1315). An excimer laser- pumped dye laser was used and the detection limits for 15 elements varied between 3 and 1 pg ml-l for Mg and Na and 30 and 24 ng ml-1 for Bi and Cr.An extremely low detection limit of 8 pg ml-1 was reported for T1 by Omenetto et al. (S/1099) using two excimer laser-pumped dye lasers as described previously. Current progress in LEI sensitivity and interference suppression seems likely to lead to increased interest in the application of the technique to real sample analysis. One such application concerned the use of LEI for the direct determination of organotin compounds in air (S/308). A single-step excitation at the 284-nm Sn resonance wavelength produced by a frequency doubled nitrogen laser- pumped dye laser system was used to give sensitive detection of tin compounds. 3.6.3. Other studies Resonance ionisation spectroscopy in which laser radiation is used to generate ions directly, can be used with optogalvanic detection as in LEI, mass spectrometry (RIMS) or normal ion counting techniques. The technique of RIMS is undergoing rapid development and has generally been considered as outside the scope of A R A A S reviews.One paper this year, however , described an interesting development using a pulsed glow discharge lamp as a source of atoms for laser-excited RIMS (861C538). Ionisation spectra of Cu by one-photon absorption from high atomic energy states populated at low levels have been recorded by mass spectrometry. Two-photon absorption at 302.06 nm for Fe, or 359.35 nm for Cr, was also used to promote ground-state valence electrons directly into the ionisation continuum for RIMS measurement. The advantages of using a GDL as an atom source for RIMS appear considerable.JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 143R Laser induced breakdown spectroscopy (LIBS) is another application of laser technology promoted in recent years (see ARAAS, 1982,12,4 and ARAAS, 1983,13,4). In the present review period, the determination of Cd, Pb and Zn in aerosols (S/C340, S/C1132) and the determination of Cr, Mn and Ni in solid steels (86/443) have been described. Perturbations of temperature, electron density and line intensity in an air plasma generated by LIBS, caused by the presence of small amounts of Be and Na have been determined (S/C1131), and would appear to be of considerable relevance to the accuracy of analytical measurements using this technique. Papers on atomic spectroscopy by degenerate four wave mixing (S/C342) and cross-beam saturated interference spec- troscopy in flames (86/1400) were also of interest.4. ELECTROTHERMAL ATOMISATION The 14-month period covered by this review has not seen any startling new developments in electrothermal atomiser design, performance or in our knowledge of the fundamental processes taking place in such systems. There has, however, been steady progress towards the development of practical isothermal atomisation systems and in the direct analysis of solid samples. Useful reviews have appeared (S/487, 86/675), that by Chang and Chakrabarti (86/675) giving much valuable data on the use of graphite furnaces heated by a capacitive discharge, A review paper by Sturgeon (86/C479) highlighted the problems in interpreting 02-concentration measurements during electrothermal atomisation, while that by De Loos- Vollebregt and de Galan (86/18) on the Zeeman effect will undoubtedly become a reference source for many years.Two reports are likely to be of more than passing general interest. In one, a new patent described a novel atomisation system consisting of a double tube arrangement (86/78). The inner tube is wrapped around with a high-frequency coil and this is covered by the outer graphite tube. The inner tube, in which the sample is placed, is uniformly heated by this arrangement, and this design may be an important contribution towards the ideal isothermal furnace. In the other, the RSC Analytical Methods Committee on the Evaluation of Analytical Instrumentation deals with the design features of atomic absorption spectrophotometers intended for use with elec- trothermal atomisers (86/209).Their report is essential reading for all intending purchasers of modern atomic absorption instrumentation. 4.1. Atomiser Design Most of the analytical procedures described in the current literature utilise conventional tube-wall or platform atomis- ation with commercially available instrumentation. The estab- lished limitations of many of these procedures have, over the years, led to the development of modified designs of atomiser tube, to investigations of alternative tube materials or coatings, and to the development of systems that operate closer to isothermal atomisation conditions.A new atomiser system of considerable interest has been described above (86/78). The period covered by this review has been notable for investigations of the use of metal tubes or graphite tubes with metal carbide coatings. Although few of these or other publications describing unusual atomiser designs represent novel ideas, many do provide interesting new information with which to evaluate existing concepts. The tube in tube technique of Sperling (S/168, S/C513) has been modified by use of an inner tube with three bars (1 X 1 mm) running over the whole length of the tube. This is said to minimise contact with the outer tube and smooths the temperature profile within the inner atomisation tube. A tube in tube approach has also been reported by Marinescu (86/673) for the electrostatic sampling of atmospheric particu- lates.A smaller graphite tube (6.5 mm i.d., 7.0 mm o.d., 14 mm long) is cemented with vapour generated pyrolytic graphite inside a standard 8.5 mm i.d. Pye Unicam SP9-01 furnace tube. Two end disks serve to maintain the inner tube in a fixed central position. This paper describes some other interesting platform designs also used for the direct collection of atmospheric particulates. A new long tube (145 mm) furnace with an independent sample introduction system has been described by Wen-Jang Wang et al. (86/C829). The long graphite tube (0.d. 9.5 mm, i.d. 7.1 mm), which acts as the heating element, has an internal alumina tube (0.d. 6.8 mm, i.d. 4.8 mm) through which the sample is passed. Solid samples are evaporated from a small independent graphite tube furnace mounted inside a quartz envelope and the vaporised material is transferred to one end of the alumina tube.This device has several unique features, but to date has only been used to measure the dissociation temperature of AsH3 using an atomic absorption procedure. An experimental evaluation of the effects on analytical performance caused by blocking off the usual central injection hole and by varying the length of a CRA-90 graphite furnace system has been reported (S/170). Expected improvements of 2-3 times were obtained using a 12 mm length of tube with no injection hole compared with a conventional tube. Attempts aimed at reducing the cycle time of an ETA procedure to less than 30 s using five different standard or modified Massmann furnace designs failed to reach the required objective (S/644).The systems were assessed for their suitability for the determination of Cu and Zn in plasma protein fractions and the fastest operation was obtained with a Massmann furnace tube fitted with an interchangeable sample cup. The direct analysis of solid samples has been achieved by a novel atomic absorption system with a combined graphite furnace - air - C2H2 flame atomiser (S/850, 86/C937). Samples (up to 0.2 g) were placed in the furnace and atomised into a slotted quartz T-tube mounted in the flame. The sensitivity was reduced by 10-200 times compared with the direct graphite furnace method, but this allowed larger sample masses to be used minimising problems caused by sample inhomogeneity.Elements such as As, Cd, Co, Cu, Mg, Pb, Sb and Se were studied in both biological and geological samples. A contoured graphite tube has been described and was shown to give the same temperature - time characteristics obtained with a platform (SC1167, 86/C534, 86/C777). The inversion of the temperature gradient along the length of the tube provided similar freedom from matrix interference effects as a platform, but matrix modification was required to overcome residual interferences. It was claimed that the contoured tube performs as satisfactorily as a platform - tube combination and is substantially cheaper. Modification of the temperature profile of the tube through changes in the tube wall has also been used in a novel laminar flow atomisation system (86/C774).In this system, the carrier gas and the atomic vapour flow axially through the tube. The laminar flow provides a marked reduction in background absorption combined with improved sensitivity. Modification of the temperature profile prevents thermal diffusion of atoms against the flow of carrier gas and allows the gas to be pre-heated before reaching the atomisation surface, which is a “covered” platform. Of the many approaches to achieving isothermal atomisa- tion conditions, the platform technique has become most widely established due to its simplicity and the ease with which current commercial systems can incorporate platform technol-144R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 ogy. It is clear however that, whilst the platform provides a useful delay in the release of the sample from the atomisation surface, the temperature of both the tube wall and the platform are still increasing at the time that atomisation of the analyte takes place (86/C534).Recent years have therefore seen a search for alternative systems that more closely approach ideal isothermal conditions. The technique of second-surface atomisation has been investigated by Hol- combe and co-workers and recent developments have been described in two conference presentations (S/C252,86/C905). Their current system involves the insertion of a gas cooled tantalum plug into a hole machined through the furnace wall above the sample injection site. Condensation of the analyte on the cooled plug takes place evenly and the subsequent atomisation signal is much less dependent on the physical form of the sample and matrix interferences.Data on the efficiency of analyte transfer to the plug, the effects of different coolant gases, the temperature differential between the plug and the furnace wall and application to complex aqueous and solid samples were presented. Publication of this work is awaited with interest. A similar effect to that of the plug has been achieved by placing a graphite lid over the centre of a graphite tube in an integral cup - furnace configuration (861689). Another valuable approach to isothermal atomisation is provided by the two-step furnaces described in recent years by Siemer (86/C941) and Frech and co-workers. Two new devices of this type have been patented recently (S/147,86/C516) and commercial evaluation is almost certainly in progress.The separation of the volatilisation process from the atomisation step results in a considerable reduction in interferences, although at the cost of providing two independent power supplies (86/C522). A novel system has been described by Jotov (86/C5 16, 86/730). The two separately heated graphite components consist of a main furnace tube and a sample cup that is placed at the bottom of the furnace with no contact between them. The furnace has four slots cut in the walls that limit the diffusion of the atoms along the tube to the central volume, which is effectively at constant temperature. When the main furnace has reached constant temperature, the sample cup assembly is raised and is heated rapidly.Results were presented for Mn and Pb, and a method for the direct determination of Pb in whole blood without matrix modifi- cation showed excellent recoveries. Recent work on the two-step furnace developed by Frech and co-workers has been concerned with its application to the graphite furnace atomic emission determination of A1 (86/197), which is discussed more fully in section 4.6. Probe atomisation is another attractive approach to the achievement of isothermal atomisation conditions and the further development of this technique has been described in several publications. The most common method of probe introduction is through a slot cut in the centre of the side wall of the graphite atomisation tube. This is termed front-entry probe introduction.This method has been evaluated for the simultaneous determination of up to 15 elements using continuum-source atomic absorption spectrometry (86/665). A compromise atomisation temperature of 2700 "C was found to give efficient atomisation and good peak height sensitivity for all elements, and detection limits were comparable to tube-wall and platform atomisation detection limits obtained with the same spectrometric system. A problem noted with front-entry flat probes is the tendency for solutions containing high concentrations of nitric acid to spread back along the stem of the probe during the drying stage, part of the sample thus ending up outside the atomisation tube. A stepped-probe design has been reported that overcomes this problem and allows the introduction of solutions containing up to 20% V/V HN03 without droplet spreading (86/C775).An alternative approach to this problem involves introducing the probe from the open end of the graphite tube in an end-entry probe configuration, and this has been evaluated using both flat probes (86/1357) and tubular probes (86/C775). On the flat probe, spreading is restricted to that part of the probe which remains inside the furnace, and with the tube probe, spreading is constrained within the inside surface of the probe. Both systems operate more conveniently with atomisation tubes of greater diameter than current commercial designs. Two interesting applications of the probe technique have been reported. He Xiuren et al. (86/C928) described the use of a porous graphite probe both as a filter for the collection of atmospheric particulates and as the atomisation surface in a graphite furnace system.The direct analysis of the particulate samples avoids sample contamination from dissolution pre- treatment procedures, and provides a simple, sensitive, interference free technique, which was applied to the deter- mination of Cd, Cu, Ni and Pb. A tungsten wire coil probe has been applied to the determination of Pb in blood and melted snow (S/28). The coil was made of 0.33 mm thick wire, had an i.d. of 0.9 mm and could be used for up to 200 firings. 4.2. Atomisation Surface Although the use of electrographite tubes coated with pyrolytic graphite is becoming almost standard and is steadily replacing the use of uncoated tubes, several groups continue to promote the use of alternative atomiser substrate materials.The period of this review has seen much activity in the evaluation of both tubes made totally of pyrolytic graphite and of metal tube atomisers. The advantages reported for total pyrolytic graphite tubes suggest that this type of tube may become the standard when it is available for a wide range of commercial atomiser systems (S/822, S/880, 86/198, 86/C518, 86/C765, 86/C923). Tubes are made by a vapour deposition method using the hot-wall technique, in which a substrate is heated by a surrounding element while a feed gas flows through the enclosure. This method ensures that the sub- strates are kept at a steady temperature during the deposition process, and provides a more reproducible product, which is known as continuously nucleated pyrolytic graphite (86/198).After deposition, the enclosure is cooled at a controlled rate to minimise stresses and the deposited material detaches from the electrographite former owing to the differing coefficients of expansion. Numerous advantages are claimed for this substrate material including greatly extended tube lifetimes, considerable improvements in sensitivity, particularly for less-volatile elements such as Al, Cr, Mo, Pt and V, and more constant performance in terms of sensitivity and reproduci- bility throughout the lifetime of the tube. Many of these advantages are derived from the lower thermal mass of the total pyrolytic graphite tubes and the anisotropic properties of the material.Scanning electron microscopy (SEM) has been used to investigate the corrosion of total pyrolytic graphite and glassy carbon tubes (86/C533, 86/C764, 86/C887). Lifetimes of pyrolytic graphite tubes investigated in these studies were said to be no longer than for a pyrolytic graphite coated poly- crystalline graphite tube with a pyrolytic graphite platform (86lC533). After 600 determinations of V, a pyrolytic graphite tube showed substantial corrosion and carbon nodule forma- tion as well as a widening of the distance between pyrocarbon layers. Glassy carbon tubes showed evidence of significant carbide formation suggesting that even this highly unreactive material may become quite reactive at high temperatures (86/C887). Deposition of previously volatilised carbon was not observed in glassy carbon tubes, consistent with other evidence of higher partial pressures of oxygen during atomisa- tion owing to the absence of carbon in the vapour phase.For both of these new materials, the manufacturing process used appears to influence significantly the properties and per- formance of the products and further developments will be awaited with interest.JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 145R Most of the current research in the field of metal atomisers is based on the use of tungsten substrates, although Suzuki et al. (86/1455) continue to evaluate their molybdenum micro- tube atomiser and this year reported a study of the atomisation behaviour of TI. For some years now, Sychra and co-workers have developed the use of tungsten tube atomisers and have promoted the commercial development of the WETA 80 and WETA 82 instruments (S/582, 86/C530, 86/C768). Although the atomiser can be heated to temperatures as high as 3200 "C, a scanning electron microscope study of new and used atomiser surfaces has shown that lifetimes are limited by recrystallisa- tion of the tungsten on heating and cooling at high tempera- tures, and the consequent increasing brittleness of the material that leads to crack propagation (86/C530, 86/C764).A recent conference abstract (86/C768) has mentioned the investigation of different techniques for isothermal atomisa- tion with a tungsten furnace atomiser, these included: fast heating of the tube walls; tungsten platforms; the autoplat- form technique achieved by differential heating of different sections of a specially designed furnace; and the use of a cold or resistively heated tungsten loop as a sample carrier (presumably a probe).Detailed publication of this work is awaited with interest. Some interesting applications of tungsten atonzisers have also appeared. The WETA 80 system has been used for the determination of Ba in steel (S/582). Atomisation was at 3100°C in an Ar - H2 atmosphere, but tube lifetimes were reported to be as low as 80-100 cycles. A tungsten boat shaped atomiser has also been developed for the determination of Cd in coal (86131 1), and a wire-coil atomiser has been used for the determination of a wide range of elements in potable and waste waters (S/26,86/241).A tungsten-coil atomiser has been described for use with Zeeman-effect ETA-AAS (86/C656). The wire is of 2 mm diameter and is wound into a 10-coil configuration of diameter 10 mm and length 46 mm. Analy- tical performance was not described. A tungsten-ribbon furnace has also been used in a system with Zeeman background correction (S/C266, S/C268, S/844). The standard ribbon consists of a piece of 0.076 mm thick tungsten with a width of 6.38 mm and length 38 mm (S/C266). This has been used for the determination of Al, Bi, Cu. Fe and Sb in solder (S/C266), As, Sb and Se in biological and environmental materials (S/844) and A1 in acid rain and biological samples (S/C268). Stable signals for A1 were only achieved when a layer of tungsten carbide was formed on the surface.This was produced by atomisation of a solution of xylene saturated with propane. Two groups have reported the beneficial effects of the application of tantalum-foil linings inside graphite tubes for the determination of rare earth elements (S/23, S/507). In one study (S/507), sensitivity improvements of 1040 fold were achieved for Ce, Gd, La, Lu, Pr and Tb compared with a pyrolytic graphite coated electrographite tube. In the other, Dy, Er, Eu, Ho and Sni, were determined with good sensitivity with an absence of memory effects (923). Lifetimes of the graphite tubes were extended to more than 200 firings owing to the low atomisation temperatures that could be adopted using the tantalum atomisation surface. Tungsten and tantalum foil liners have also been used in the study of Pb atomisation, which was free from interference from a wide range of matrices under these conditions (861740).The most commonly used modification of the atomisation surface involves forming a coating of a different material on the basic substrate. As mentioned above, the pyrolytic graphite coated electrographite tube is probably used more than any other material at present. Recent scanning electron microscope (SEM) studies of such tubes have revealed that only small losses in sensitivity result even from heavily corroded coatings (86/261, 86/C766). It has also been shown that when used with a platform, the quality of the tube surface has a more significant effect on atomisation efficiency than does that of the platform (86/C766). The SEM studies showed that tube thinning occurs predominantly on the outside of a coated tube, corrosion of the inside surface being caused only in the presence of highly aggressive solutions (86/261). These workers also noted the formation of graphite nodules around the hottest parts of the graphite tube.Interest in metal carbide coatings of graphite tubes has revived and advantageous results have been reported from the use of hafnium (S/41), lanthanum (S/114), molybdenum (S/872), niobium and tantalum (86/91), tungsten (861C521) and zirconium (9479, S/502) carbides. Many of these studies are concerned with applications, but several are worthy of mention. The determination of Sn in edible oils and fats was made much easier with a tube coated with niobium or tantalum carbides (86/91).Matrix interferences were removed and the complete destruction of triglycerides was possible without the loss of organotin compounds. An exceptional detection limit of 0.3 yg 1-1 of Sn was achieved by direct injection of samples following dilution with IBMK. The presence of a molybdenum carbide coating effectively suppressed the spectral interference of iron on the determina- tion of Se and made the use of Zeeman-effect background correction redundant (S/872). Zirconium carbide coated tubes have been used for the determination of P in plant materials (S/502) and A1 in serum (S/479). In the first example, the sensitivity for P was increased by ten fold using the zirconium- treated tube. The detection limit for A1 in serum was as low as 0.7 pg 1-1 and may be useful for the study of the normal ranges of this element in serum.4.3. Sample Introduction Alternatives to the traditional injection or nebulisation of a sample solution on to the tube wall or a platform for ETA-AAS determination are now of increasing variety and application. The most obvious examples of two-step furnaces and probe atomisation in which the sample vapour is released into a pre-heated furnace atmosphere, are discussed in section 4.1. Electrolytic deposition appears to be an attractive means of sample pre-concentration and the review period has seen two reports of this combined method with ETA-AAS. Electro- deposition of Ag, Cd, Cu and Pb on to graphite electrodes was described by Veber etal. (S/231). Atomisation was carried out in both HGA-70 and CRA-90 atomisers.Mercury has been determined at sub-pg 1-1 concentrations by electrolytic deposition on to a platinum wire cathode, which was then placed in a graphite cup for atomisation (86/693). A detection limit of 0.04 yg 1-1 was reported, and selective deposition at a controlled potential was used to avoid possible interferences from metal ions commonly found in water samples. An analogous approach has been adopted for the collection of atmospheric particulates by electrostatic precipitation, although in this instance samples were collected directly in the tube or on the platform used for atomisation (86/673). A probe system has been used for the direct collection of atmospheric particulate samples by filtration, the probe being inserted into a pre-heated furnace for atomisation (86/C928).The two last systems are described more fully in section 4.1. At present, there is intense interest in the use of ETA for the direct analysis of solid samples. Despite the difficulties of sample size and inhomogeneity, and the provision of an adequate means of calibration, more and more workers pursue this approach as a means of avoiding complex sample dissolution procedures and the inherent problems of contami- nation in all sample-handling steps. In the review period, considerable progress has been made in the adaptation of commercial furnaces for solid sample addition. One company has produced a graphite cup that can be loaded with the required mass of sample, normally ca. 1 mg or less, and then inserted into a hole cut into the wall of the pyrolytic graphite146R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 coated electrographite tube (86l192). Extensive evaluation of this cup in tube device, with Zeeman background correction systems, has now been reported (S/C267, S/C571, 86/192, 86/C844, 86/C938). The solid sampling cup is made of high-density electrographite coated with pyrolytic graphite and has the dimensions 7.0 x 4.5 x 6.8 mm and a mass of 160 mg. A special tweezer is required to insert and remove the cup from the furnace, The mass of the cup delays sample volatilisation until the tube temperature has stabilised, and in practice it therefore behaves in an analogous manner to a platform and is consequently beneficial in reducing vapour phase interferences. Zeeman-effect background correction is used to provide accurate measurements in the presence of the large background signals generated.The removal of many interferences allows the use of aqueous standards, but peak integration is recommended due to the different atomisation behaviour of solid samples. The sample masses required to avoid problems of sample handling and inhomogeneity, often necessitate the use of alternative less sensitive wavelengths and suitable options have been characterised. The commercial cup in tube device has been used by Thomasson and Radziuk for the determination of A1 in human biopsy samples (86/C558). Masses in the range 0.5-3.0 mg were used and the A1 line at 257.5 nm was employed to reduce the sensitivity by about a factor of 10 compared with that of the resonance line at 309.3 nm.Addition of 10 pl of 2% V/V HNO3 to the cup with the sample improved the reproducibility. A graphite-boat technique has been used for the determi- nation of a range of trace elements in biological materials including many plants (S/182). It was claimed that sample masses as low as 50 yg could be used if the samples are efficiently homogenised. A detailed study of the determi- nation of trace elements in single ion-exchange resin beads has been reported (86lC657). Beads were added individually to a commercial platform atomiser with forceps, and as they are of uniform size and mass, this obviated the need for weighing. In this instance, addition of 10 y1 of concentrated HN03 was found useful as an ashing aid for the elimination of signal depression by the bead matrix.Novel atomiser designs have been developed for the determination of trace elements in environmental samples (86lC455). Apparently, one atomiser was in the form of a crucible and the other had independent heating of the evaporation and absorption zones as in a two-step furnace. Headridge and co-workers have for many years developed and evaluated the use of an induction furnace for the direct atomisation of solid samples. In the present period they have reported the determination of Pb in nickel-base alloys (86l1027) and Cr in gallium arsenide (86lC143). The Cr determination employed Smith - Hieftje background correc- tion to overcome the severe molecular absorption from this matrix. The most attractive alternative to the direct addition of solid samples is the injection of slurries of solid samples via the normal autosampler pipetting systems.The reduced depen- dence of ETA on particle size effects compared with systems based on nebulisation means that grinding requirements are less severe, but it is still essential to ensure that slurries are stable throughout the period of time spent on the autosampler turntable, and that the sample size is small enough and the slurry concentrated enough for reproducible pipetting. Jack- son and co-workers in a series of reports this year (86/C168, 86lC514, 86/659, 86lC935) have identified some interesting characteristics of the ETA of soil slurries for the determi- nation of Cd and Pb. Investigations of different particle size fractions revealed that pipetting efficiency was only impaired for particles >50 pm, and that incomplete recoveries observed between 20 and 50 ym were due to inefficient atomisation (86lC168, 86/C514).Differences in peak shape between slurries and aqueous standards observed for furnace tube wall atomisation were removed by using platform atomisation. This problem was shown to be associated with the organic carbon content of the soil, and was ascribed to the loss of Pb as organolead compounds during the atomisation of the soil (86/C168, 86lC514). In this work, slurries were prepared by stirring magnetically in a beaker of distilled or de-ionised water before injection. This approach was also used by Miller-Ihli (86/C904) in the simultaneous multi-element analy- sis of samples by continuum source AAS.Zeeman-effect background correction has been used to advantage in slurry sample atomisation for the determiantion of Pb in river sediments (86l1436) and As in pulverised coal fly ash (S/C265, S/C572). In the latter instance, particle size was reduced below 50 pm, and the sample shaken for 60 min with a solution containing HN03, LiB02, Li2B407, LiN03 and Ni(N03)2. The reason for this complex solution is not specified in the abstracts received. The mixture was homogenised by ultra- sonic agitation whilst in the autosampler cups on the elec- trothermal atomiser. A slurry method has been reported for the ETA-AAS determination of a wide range of elements in aluminous earth samples (86lC289). An alternative to continuous mixing or agitation of slurries is the formation of a stable slurry by suspension in a solution of a thixotropic thickening agent (86l664).A procedure using Viscalex HV30 in this way has proved successful for the determination of Pb in spinach, and it was shown that suspensions of powdered spinach of up to 10% mlV could be successfully prepared and were sufficiently stable for auto- matic dispensing devices. The use of oxygen during the ashing stage was effective in removing almost all the background signal from this matrix and permitted direct calibration with aqueous standards. The importance of ashing biological samples in the presence of oxygen has been confirmed in a report on the determination of Pb in liver homogenate using a slurry ETA-AAS procedure (SlC246).The commercial development of hardware for the introduc- tion of samples into electrothermal atomisers by nebulisation and aerosol deposition has ensured that the advantages and limitations of this technique have become well established. In a recent paper, Wennrich et al. (86/987) described the use of ultrasonic nebulisation for the introduction of samples con- tinuously into a constant-temperature furnace and for discon- tinuous atomisation following aerosol deposition. As expec- ted, the sensitivity values for continuous ETA-AAS measure- ment lie between normal ETA-AAS and FAAS values, whilst much improved sensitivities are achieved following aerosol deposition. Interestingly, the optimum sensitivities for Ag and In were obtained by aerosol deposition using an argon carrier gas flow-rate of 5.5 ml s-l and a deposition surface tempera- ture of 690 K.Sample introduction in ETA-AAS by vapour transport of hydrides following hydride generation has also been extended by using the furnace as a collection or pre-concentration surface (86/C902). Heating the furnace at 600-900 K induces the decomposition and deposition of hydride-forming elements, which can be subsequently ato- mised. The interference-free determination of As, Sb and Se in biological and geological materials and sea water has been reported using this procedure. The combination of chromatographic techniques with ETA- AAS continues to generate considerable interest, particularly for the speciation of organometallic compounds in environ- mental samples. Thus the past year has seen reports on the gas chromatography ETA-AAS of alkyl selenides (S/595), alkyl- lead compounds (Sl1124) and organomercurials (86/672), and the liquid chromatography ETA-AAS of alkyllead com- pounds (S/485) and organotin compounds (S/587).Some interesting atomisation and coupling devices have been reported in these papers. The determination of Hg was achieved in a novel carbon T-tube atomiser (86/672), and a fraction microcollector has been used as an interface between HPLC and ETA-AAS for the detection of organotin com- pounds (S/587). An automated GC-ETA-AAS system wasJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL. 1 147R used to study the decomposition and atomisation of alkyllead compounds in a heated quartz tube atomiser (S/1124).Long-term stability was extended by use of a purge of air during solvent elution on the GC, but the introduction of hydrogen was essential to achieve efficient atomisation of alkyllead compounds. The Pb not atomised in air or nitrogen gases was deposited on the surface of the quartz walls, and was recovered and atomised rapidly on reintroduction of hydrogen. A simple chromatographic procedure not involving GC or HPLC has been reported for the speciation of Pb and methyllead compounds in water samples (86/1390). These species are ethylated by reaction with sodium tetraethylborate and are then liberated and transported to a cryogenic trap filled with chromatographic packing. Subsequent mild ther- mal desorption affects speciation of the ethyl derivatives of the original compounds according to their boiling-points.Detec- tion limits by quartz tube AAS were as low as 8.7 pg for Me3Pb+ and 10.5 pg for Me2Pb2+ in 50-ml water samples. 4.4. Fundamental Processes The role of oxygen in both the charring and atomisation stages of ETA is continuing to receive considerable attention. Apart from the use of oxygen as an ashing aid in the determination of Pb in slurried materials referred to above (S/C246, 86/664), it has also been found useful in determinations of Pb in whole blood (S/C691, 86K901) and A1 in serum (S/858). Reduction in the accumulation of carbonaceous residues (S/C691, 86/C901), improved precision and reduction of interferences (S/C691, 86/C901) and smaller variations in sensitivity during the lifetime of the atomiser tube (S/C691, S/858) are amongst the advantages claimed.It also reduces the non-atomic absorption signal from biological samples in general (S/495). The concentration of oxygen present during the atomisation stage of furnace operation has been the subject of controversy for a number of years (see ARAAS, 1983,13,40 and ARAAS, 1984, 14, 42). It has been demonstrated that thermal or temporal shifting of the absorption signal occurs for some elements in response to changes in the partial pressure of oxygen (S/1095,86/C480,86/1101). Calculations of the magni- tude of the changes in appearance temperatures for Pb, Si and Sn using a gas-phase equilibrium model have been shown to agree with experimental observations (86/C480). Hetero- geneous equilibrium between O2 and C(s) is not however achieved in a furnace below 2100 K, and consequently accurate equilibrium calculations of oxygen partial pressure are difficult or impossible (86/C479).It has been postulated that both O2 and CO may affect both the kinetics of atom formation and observed interference effects (86/C479), and this should have an important influence on future atomiser design as more rigorous exclusion of atmospheric O2 should be advantageous. It seems clear that increasing O2 levels will depress the thermal dissociation of analyte oxides, and that the role of active sites on the tube surface is extremely significant (S/1095). Sturgeon et al. (S/1095) have postulated that the chemical inertness of glassy carbon tubes will be a serious drawback in practice because the low surface reactivity may amplify some types of matrix interferences.It has been observed that the concentration of O2 in the gas phase during atomisation is influenced by the presence of ascorbic acid in the analyte solution, and by the treatment of tube surfaces with tungsten or zirconium compounds (86/1022). The total amounts of carbon monoxide formed during atomisation have been determined by linking a detector system for carbon oxides to a gas-tight graphite furnace (86/C769). The level of CO produced was found to vary between 0.1 and 2.0 pmol depending on the type of graphite used, the amount of matrix and the ashing temperature. The influence of very high heating rates on the atomic absorption sensitivity of a wide range of elements has been reported (S/635). Rates of 4000Cb75000 K s-l gave an increase of 140-390°/0 in sensitivity for most elements, but lower sensitivities were obtained for Bi, Cd, Pb, T1 and Zn compared with standard furnaces.The effect of ramp rate on the axial distribution of tube temperature, i.e., along the tube, has also been studied by Falk et al. (861121). With constant cross-section of the tube wall and ramp rates >lo00 K s-1, a nearly constant temperature was observed along the largest part of the tube length as long as the initial temperature was close to ambient. At lower ramp rates of between 100 and 1000 "C s-l, considerable deviations from this equilibrium situation were observed and the axial temperature drop was increased. A significant axial variation influences the diffusion rate, the expansion of gas within the tube and the rate of condensation of analyte vapour at the cooler ends of the tube.Falk has also shown that this axial variation must be taken into account when the platform furnace configuration is considered (86IC776). Model calculations of platform temperatures have been compared with experimental measurements obtained using an IR-pyrometer at 7 pm, which were corrected for errors caused by the reflection of tube-wall radiation from the surface of the platform. The results were used to derive optimum platform configurations, but also showed that the platform was heated by conduction and electrical heating caused by the lengthwise voltage drop, as well as by radiation. Pelieva et al. (86/1311, 86/1440) have also described a mathematical model for platform heating, the results of which were confirmed experimentally. Methods for stabilising the temperature of the platform have been compared (86/1311). A valuable study by Doidge (86/107) revealed that radiation leaving the central hole of tubular graphite furnace atomisers may deviate significantly from ideal black-body behaviour.Pyrometric measurements at various wavelengths showed an apparent decrease in temperature with increasing wavelength, consistent with a cavity radiator with an emissivity less than unity. Deviations from unity are caused by the open nature of tube furnaces, plus possible contributions from the axial temperature gradients and the relatively high surface finish of the tubes. Using a Varian GTA-95 furnace and pyrolytic graphite coated tubes, effective injection hole emissivity values between 0.76 and 0.92, depending on temperature and wavelength, were reported (86/107).It appears that many reported pyrometric temperature measurements may be in error. It is recommended that the pyrometer operating wavelength should be as short as possible to minimise temperature measurement errors. A new method for measur- ing vapour-phase temperatures has been proposed for graphite furnaces based on molecular fluorescence of OH (86lC535). This utilises the 308-nm line from an excimer laser with XeCl as the lasing medium, which coincides with several strong absorption lines of OH. The wide range of analytical techniques being applied to the study of atomisation mechanisms is providing a wealth of valuable data with which to interpret and optimise analytical procedures.The review period has seen reports of the use of radiotracers, MS, ESCA, electron microscopy, SIMS, XRD and Auger spectroscopy applied variously to both vapour phase and condensed phase stages of the atomisation process. The problem with all such measurements concerns their application at the sensitivity and conditions relevant to normal furnace operation. The use of mass spectrometry to sample and analyse furnace gases highlights the nature of this problem as a furnace vapour at atmospheric pressure must be sampled into a system working under high vacuum conditions (see ARAAS, 1984, 14,42). Nevertheless, the information derived can often be very useful (86/C762, 86/C767, 86K900, 861 C936).Mass spectrometric sampling at atmospheric pressure has been achieved by forming a molecular beam from free-jet expansion of the furnace gases. A tungsten sampling cone, containing a 0.06-mm orifice at the apex, samples from the injection hole of the furnace and a skimmer cone, nested with the sampling cone, forms the molecular beam in a differen-148R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 tially pumped vacuum system (86/C767, 861C900). The beam can be mass analysed with the simultaneous measurement of the furnace absorption signal. This combination has been used to demonstrate pre-atomisation losses of Se as the oxide and Se2. When nickel is used as a stabiliser for Se, it appears that nickel blocks the active carbon sites allowing the formation of nickel selenide. However, another mass spectrometric study reported this year produced conflicting results for this system (S/C271).Selenium was released as SeOz and SeCO at a different time from the release of Ni, as Ni02, NiC2 and Ni. No nickel selenide was observed. It was concluded that nickel only indirectly affects the vaporisation of Se from a graphite surface as there is no correlation between the appearance times of Ni and Se. Mass spectrometric monitoring of the vapour produced no atomic Se signal suggesting that all the Se is vaporised in molecular form and that gas-phase reactions are responsible for the formation of atomic Se (S/C271). The characteristics of lead atomisation have again been the subject of a number of studies.Optimum ashing temperatures both with and without ammonium dihydrogen phosphate as a matrix modifier and with and without a platform were studied using 2(J3Pb as a radiotracer (S/191). Combination of the matrix modifier and the platform allowed an ashing tempera- ture of 1000°C to be adopted and reduced matrix inter- ferences from blood and urine samples. Mass spectrometry (S/253,86/C762) and ESCA (SA094) have been used to study surface reactions during Pb atomisation. Mass spectrometric studies revealed the formation of lead phosphate in the presence of phosphate as matrix modifier, but suggested that a chemical bond to the graphite was also present, as an analyte absorbance peak was observed that was sharper than would be expected for a metal weakly physisorbed on to the surface (861C762).X-ray photoelectron spectroscopy and SIMS were also used to identify species present on the surface of the atomiser prior to evaporation (S/C253). The formation of two different lead oxide species on the surface of both graphite and pyrolytic graphite tubes was indicated by ESCA measure- ments (S/1094). A constant-temperature furnace has been used to study the mechanism of Pb atom formation in the presence of carbon powder (S/144). The results suggested that the important reaction is thermal dissociation of PbO(s), as the rate of reduction by carbon is slower. Detailed studies of the influence of the nature of the graphite surface on the interference of magnesium chloride on Pb absorption have also been presented (S/C247, 86K845).Several interesting contributions have been made to the study of the atomisation mechanisms of elements that form thermally stable carbides. A useful overview of factors that influence the atomisation of V in modern graphite furnaces was reported by Manning and Slavin (86/116). Recommended conditions include wall atomisation from tubes with good coatings of pyrolytic graphite, Mg(N03)2 as a matrix modifier and a cool-down procedure between the char and atomisation steps of the furnace programme. The latter helps to establish a nearly constant temperature along the tube as confirmed by the work of Falk et al. mentioned above (86/121). It was reported that elements forming very refractory carbides, such as La, Mo, W and Zr remain troublesome for V due to the formation of mixed carbides with VC (86/116).The chemical reactions of Cr and V were investigated by Wendl and Muller-Vogt using XRD and electron microscopy (86/74). The formation of carbides of both elements, Cr3C2 and VC, respectively, were confirmed, and the improved sensitivity in pyrolytic graphite coated tubes was said to be related to the porosity of uncoated tubes. A kinetic study of the atomisation of Cr, Mo and V also indicated analogous differences in the rate of atomisation between coated and uncoated tubes (864331). Further detailed information has also been repor- ted on the chemical reactions occurring during the atomisation of Mo (86/C772). Electron micrography, XRD, energy dispersive XRF and Auger spectroscopy were used to identify Moo2, Moo3 and Mo40tt in the solid phase below 1500 K, and to confirm the formation of Mo, MoC and Mo2C at higher temperatures on both pyrolytic graphite and electrographite surfaces.Cedergren et al. (86/C885) have established theoretical conditions for the formation of stable solid as well as gaseous carbides of Al, Ba, Be, Cr, Fe, Mn, Se, Si and V. The solid phases were analysed by ESCA and Auger spectroscopy. The results were used to estimate the partial pressure of 0 2 in the vicinity of the graphite surface under normal working conditions. Muller-Vogt and Wendl (86/C532) reported studies of elements that are atomised through the intermediate forma- tion of oxides using X-ray diffraction measurements of solid phases on tube surfaces. For Al, only A1203 was detected on the tube surface, and this is assumed to be decomposed thermally.Similar processes were inferred for the rare earth elements, Dy, Eu, Tb, Tm, Y and Yb, all of which showed evidence of the characteristic oxide M203 on the tube surface. Atomic absorption sensitivity is inversely related to the stability of these oxides. Carbon reduction was however said to be involved in the production of Ge atoms from Na2Ge03 via GeO (86/C532). As in most of the past 20 years, the present review includes a series of highly informative papers from L’vov and his co-workers. One of these has emphasised the important contribution made by carbon in condensed-phase processes (S/574). The influence of the organic additives ascorbic acid, EDTA and saccharose on the atomisation of Bi203, CdO, PbO and ZnO was interpreted by means of a kinetic treatment.Two atomisation mechanisms were identified. Cadmium and Zn oxides were reduced by carbon to form the metal vapours directly, whilst Bi203 and PbO were reduced by carbon to give the intermediate formation of free metal on the tube surface, and this was subsequently volatilised. It was postulated that the increased partial pressure of carbon plays a decisive role in the carbothermal reduction reactions. The role of free carbon in the gas phase was emphasised in a second publication (S/820). Both free C and C2 (86/330) concen- trations are much higher than equilibrium values because the graphite surface becomes activated. L’vov and Yatsenko reported measurements of the partial pressures of A1 and A12C2 in a graphite furnace by observing the UV absorption of the A1 autoionisation line at 193.6 nm and the AI2C2 band at 205 nm (86/330).The concentration of molecular A12C2 averaged over the furnace volume during carbothermal reduction of A1203 is comparable to the concentration of A1 atoms. The influence of hydrogen on the atomisation of oxides has also been studied (86/744). Most oxides, for example, BaO, CaO, Cr203, MgO and MnO, are reduced directly to the metal vapour but In203 is reduced to the metal in the condensed phase with subsequent evaporation of the free metal. L’vov and Bayunov proposed a model of sample vaporisa- tion based on the Langmuir diffusion equation for the evaporation of a spherical particle (86/329). It was shown that penetration of sample solution into the graphite, reducing the effective coefficient of molecular diffusion of analyte atoms and the polydispersity of the dry sample residue, can affect the rate of atomisation and hence the atomisation process substantially.The combined thermodynamic - kinetic approach to the study of atom formation processes first decribed by Sturgeon and Chakrabarti (see ARAAS, 1976, 6, 20) has been devel- oped by Akman et al. (86/C519) and Chung (S/122). Mechan- isms identified included thermal dissociation of the oxides for Ba, Cd, Mn and Pb in one study (86/C519), and for Al, Mg and Zn in the other (S/122). Other processes include thermal dissociation of the halide for Sb, evaporation of metal for Ag, carbon reduction for Fe and dissociation of the dimer for Cu (S/122).JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 149R An interesting comparison of the atom-loss mechanism in graphite and glassy carbon tubes has been made by Zheng using a constant-temperature atomiser (S/89). In the graphite tube, diffusion is coupled with a complex reaction process due to the formation of A1 and K compounds with graphite. which have a lower vapour pressure than the elements alone. This is not observed in the unreactive glassy-carbon tube where atom loss follows a simple diffusion law. The rate of loss in the glassy carbon tube is therefore faster than in the graphite tube, but the sensitivity measured in peak-height mode is greatest in the glassy-carbon tube. Monte Carlo modelling simulation has been used to study vapour movement caused by diffusion and gas expansion, as well as absorption - desorption processes at the tube wall (S/C251). The random selection process applied to vaporisation and subsequent particle movement has provided accurate simulations of analytical measurements. Interesting conclusions reported include ( a ) about 35% of the sample is expelled through the injection hole and ( b ) vaporisation of Cu in a furnace of length 3 cm indicated that 100% of the sample was present in the gas phase at peak atom density.4.5. Interference Studies The flow of publications cataloguing chemical interferences in ETA appears to be greatly reduced. Current emphasis appears to be with the development and evolution of methods to overcome those interferences which are now well estab- lished and many papers have described the study and appli- cation of either well established or novel matrix modifiers. In commercial systems it is widely recognised that the platform greatly enhances the interference-free range of many deter- minations, and the development of constant-temperature atomisation systems, such as the probe in the research environment, could lead to further improvements in general atomiser performance. One manufacturer has described the development of a new cuvette that provides a delay in atomisation analogous to that of the platform (S/C49, S/270, 86/C924).Known as the delayed-atomisation cuvette, the tube, formed in a single piece of graphite, has ends that are thinner than the centre section and is similar to the volatile-elements tube produced some years ago for carbon furnace atomic emission measurements (see ARAAS, 1976, 6, 23).The thinner ends heat up more quickly than the centre and the sample is consequently atomised into a more isothermal environment. This system has been tested on real samples, when, in combination with aerosol deposition and efficient background correction, accu- rate results were obtained without using standard additions or matrix modification. Welz et al. (86/199) have now published some of their experiments with the dual-cavity platform referred to in ARAAS last year (see ARAAS, 1984, 14, 43). In this device, the analyte and the interferent may be volatilised separately from the individual cavities and a clearer identification of condensed and vapour phase interference reactions can be achieved.Complications, due to interactions between the gas phase and the condensed phases, must however be taken into account. In the study of the effect of nickel on Se, it was shown that all interferences disappear when nickel in HN03 is used as the matrix modifier and optimised furnace conditions are adopted. An interesting study of the effect of organic solvents on the atomisation of Cu, Ni and Pb has been reported (S/887). It was suggested that halogen containing solvents may influence the atomisation process through formation of active graphite - halogen compounds which interact with the metal to give an enhancement of volatile halide formation. This effect is diminished when the organic solvent has a high hydrogen to halogen ratio.To most users of ETA-AAS systems, background inter- ference caused by molecular absorption is a problem to be overcome, but several groups have specialised in the appli- cation of molecular absorption (and emission or fluorescence) for analytical purposes, and this subject was thoroughly reviewed by Dittrich (86/C481). The most serious problem arising in such procedures is the interference from atomic and molecular species generated in the atomiser on the specific molecule of interest. The determination of fluoride by measurement of the absorption of AlF is perhaps one of the most interesting applications of this principle. Two recent studies have illustrated the importance of interferences. In one, the interference of Sr(N03)2 on AlF absorbance was avoided by using Mg(N03)2 or Ba(N03)2 as matrix modifier (86/1279).The authors reported a sensitivity of 4.2 pg ml-1 of F- using 10-p.11 aliquots and glassy-carbon tubes. Dittrich et al. (86/986) developed an extraction - pre-concentration pro- cedure to overcome interferences simultaneously and to provide a substantial improvement in sensitivity. The F- was extracted with 10-3 M triphenylantimony(V) dihydroxide in IBMK, and stripped back into 0.025 M Ba(OH)2 solution containing 0.1 mg rnl-1 of aluminium. Detection limits as low as 0.01 pg ml-1 of F- were achieved in some matrices. The vapour phase spectral measurements developed by Titarelli et al. (86/336) have quite different aims and use the molecular absorption of fragments of organic molecules produced in ETA to characterise crude oils, pigments and polymers.Combination of an electrothermal atomiser with a diode array detector has now been developed for fingerprint identification of these matrices. The molecular absorption spectra of a wide range of molecules formed during electrothermal atomisation have been characterised by Allain and Mauras (S/495). The report includes BaC12, CaCI2 CsCl, FeC13, KBr, KCI, KI, LaC13, LiCl, MgCI2, NaBr, NaCl, NaF, NaI, RbCl and SrClz as well as albumin and blood plasma. Background absorption from metal chlorides and biological samples was reduced by addition of nitric acid and/or oxygen during the ashing stage. A method has been proposed for the evaluation of background correction systems based on measurement of NaI absorption at the Cd resonance wavelength of 228.8 nm (86/985).The authors emphasise an important point that background correction systems operate much more satisfactorily for static background absorption, for example that from a filter, than for the transient background pulse observed in electrothermal atomisation. Use of the proposed method revealed back- ground-correction errors of up to 5% using a commercial instrument system and with background signals up to 0.7 A or 0.5 A s. Background correction errors of this magnitude are to be expected from current commercial instruments due to the non-simultaneous measurement of the sample and reference signals (86/331, 86/C886). Harnly and Holcombe pointed out that most current systems employ a single reference signal either before or after the sample measurement to provide the correction.The magnitude of the error will therefore depend on the rate of change of the background signal and the speed of modulation between the two measurements. Employing an average of two measurements of the reference signal on either side, or bracketting the sample measurement reduced the magnitude of errors by a factor of 20, and using several reference measurements and a quadratic fit to give a non- linear interpolation of the background signal at the time of sample measurement reduces the error by another factor of 20. This problem reveals one of the major advantages of peak-area measurement in ETA-AAS, as integration of the corrected signal over the lifetime of the background signal will result in a cancellation of this source of error.Stray light is another potential source of error in background correction systems if the stray radiation is not effectivcly absorbed by the matrix compounds responsible for the background absorption signal. De Loos-Vollebregt and de150R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 Galan (86/C778) reported a study of the effect of stray light on background correction systems based on the Zeeman effect or the pulsed HCL. Experimental results using absorption filters or static background signals indicated that the stray light is located close to the resonance wavelength of the analyte and is therefore absorbed by the matrix components. Accurate background correction is achieved provided that the electron- ics are perfectly linear over the magnitude of the gross sample signal measurement, i.e., analyte atomic absorption plus background absorption. Although background overcompensation errors caused by spectral interferences have been established in D2-arc back- ground correction systems, a similar phenomenon in Zeeman- effect background correction was described for the first time in 1984. Wibetoe and Langmyhr investigated the effect of Fe on 30 elements and 49 element lines (S/489). Two elements, Ga at 287.4 nm and Zn at 213.9 nm were subject to substantial negative errors due to background overcompensation effects. When the magnetic field is on, the a-components of the adjacent Fe lines overlap at the position of the analyte line giving a spurious background signal that is not present when the magnetic field is off.For Ga it is possible to use an alternative wavelength at 294.4 nm, but this is not possible for Zn. Careful selection of the furnace conditions can however be used to separate, in time, the Fe and Zn signals. Wavelength modulation is the background correction tech- nique of choice when atomic absorption measurements are made with a continuum source or in ETA-AES (86/69, 86/204). An investigation of the efficiency of wavelength modulation background correction in ETA continuum-source AAS was reported and its performance compared with Zeeman and D2-arc systems (86/C780). The wavelength modulation procedure automatically brackets the analytical signal temporally as a result of the sequential measurement of background - analyte - background signals over the wavelength modulation interval.Accurate background cor- rection for up to 5% m1Vsodium chloride at the Au, Cr and Pb wavelengths was achieved in both AAS and AES modes. Matrix modification, whether combined with a platform or not, has become one of the most powerful tools for controlling interferences in routine ETA-AAS measurements. The review period has revealed numerous investigations into the use of matrix modifiers, both new and those more well established, in real analytical situations. Most noticeable has been the increasing use of palladium as a matrix modifier in a wide variety of determinations including As (86/C925), Hg (86186, 86/1040), In (86/85), Sb (8611395) and Se (S/509,86/ C837, 86/C925).Certainly Pd seems to be the Mg(N03)2 of 1985! One group has investigated the use of a mixture of Mg and Pd nitrates to stabilise a wide range of elements including As, Bi, In, Pb, Sb, Se, Sn, Te and TI (86/C513). Seven of these elements (i. e., all except Pb and TI) gave an optimum charring temperature of 1200 "C, and very similar atomisation temper- atures of 2000-2100 "C in the presence of the mixture of matrix modifiers. The charring temperatures were increased by between 300 and 900°C allowing the efficient removal of organic matrices and a substantial reduction in background signals from inorganic salts. Platinum appears to be equally effective as a matrix modifier and has been preferred in some instances for As determinations in environmental samples (86/1037), with palladium for Hg determinations in biological materials (86/86) and with nickel for As and Se determinations in biological materials (S/496).Other articles of more than passing interest have described the use of Mg(N03)2 as an ashing aid and matrix modifier in the determination of very low levels of Cr in human serum (S/616); the use of a mixture of LaC13 and HN03 to control the interferences of sulphate and halide salts, respectively, in the determination of Pb in natural and drinking waters (S/493); and the use of nickel to remove interferences and increase the sensitivity of the determination of Ga in environmental samples (S/802). Barium and nickel nitrates were also shown to increase the sensitivity and reduce interferences in the determination of Ge in semiconductor samples (S/1108).The presence of iron and phosphates in biological materials, which cause D2-arc background correction systems to over- compensate at several As and Se resonance lines, has been overcome by a mixture of modifiers containing 0.1% nickel and 2.5% platinum in 3 M HN03 (S/496, 861C536). The correlation between the wavelengths at which over- compensation occurs and strong Fe lines observed in both ICP and HCL emission suggest that the iron interference is caused by Fe atomic absorption of the D2-arc light source within the band pass (86lC536). Other investigations have, however, suggested that these errors are caused by absorption by FeO molecules formed by reaction of iron with the entrained 0 2 , common in most commercial atomisers (S/C271).The resolu- tion of this uncertainty will be interesting. The enhancement of mercury absorption by palladium is an extremely beneficial aspect of the use of this element as a matrix modifier. Sensitivities of 300 (86/86) and 85 pg of Hg (8611040) have been reported in the presence of palladium, which allows ashing temperatures of up to 500°C to be used. An interesting indirect procedure for the determination of thiosulphate was reported based on Hg absorption (S1913). Thiosulphate (as well as sulphide, cyanide and bromide) stabilises Hg in a graphite furnace. Addition of thiosulphate to excess of Hg2+ in solution, and addition to the furnace, gives a mixture of free Hg2+ and mercury(I1) thiosulphate. The free Hg2+ is removed as Hg on drying below 1OO"C, and the stabilised Hg can be determined on heating to a higher temperature, providing an indirect measurement of the thiosulphate concentration in the 10-6 M region.4.6. Developments in Technique Some interesting and perhaps conflicting observations on signal handling in ETA-AAS have been reported this year. Barnett et al. (861C484) stressed the importance of setting the base line at the beginning of each atomisation cycle particu- larly when peak-area signals are being measured. This was achieved by a technique termed "base line offset compen- sation," and it was demonstrated that a time of 4 s is optimum to achieve greatest stability and hence best detection limits. Smoothing of signals obtained with modern fast response instrumentation is essential and a 37-point Savitzky - Golay algorithm was used to show the improved SNR possible and improved detection limits in the peak-height mode.Smooth- ing had no effect on peak-area detection limits, but this was the preferred measurement mode recommended by these authors (86/C484). In contrast, Herber et al. (86K487) recommended peak-height measurement using computer aided signal processing. They showed that peak-height gives improved SNR and thus better precision than peak-area measurements, a result that is typical af many instrument systems. Signals from ETA-AAS systems are usually distorted by the effects of the instrumental response. Nakamura (S/879) established a distortion model of the instrumentation function based on the response signal. The limitations of the model were investigated using quasi-signals generated by an oscil- lator and a moving carbon rod.It has been claimed that using Zeeman-effect background correction, achieved by placing the graphite furnace between the poles of an a.c. magnet, detection limits for real samples are equal to or slightly better than detection limits for pure aqueous solutions without background correction (S/C272, S/C273). Detection limit improvements of 2-3 times have been reported for elements for which bright light sources are available, and as long as the instrumental conditions were compatible with the fast signals obtained in graphite furnace atomisation (SlC272). The possibility of achieving the deter- mination of stable Pb isotopes by Zeeman atomic absorptionJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL.1 151R spectrometry has been demonstrated (86/C652). Using a furnace at a reduced pressure of 100 Pa, in which the line profiles are affected only by Doppler broadening, produced Zeeman AAS profiles that are characteristic for each nucleide. A similar approach was adopted by Stephens (86/1399) using magnetic optic rotation and an air - acetylene flame atomiser mounted between the poles of the magnet. Some interesting instrumental developments in Zeeman- effect AAS have appeared in the review period. A new instrument system was reported in the Chinese literature (S/60), and a portable simultaneous multi-element system was described by Hadeishi (86K653). Up to nine elements could be detected with this system using two multi-element HCLs and five photocells. The photocells were synchronised to the signals from each HCL, either in time or by discrete frequency modulation.The design parameters required for the develop- ment of air-cored solenoids capable of generating pulsed magnetic fields at the strengths necessary for Zeeman-effect AAS instruments have been discussed (S/577). The coils are small and light enough to be mounted on an optical rail and the field volume is sufficient to avoid any size limitations on the source or atomiser mode of operation. A double pass Zeeman AAS spectrometer gave two-fold improvements in sensitivity for Cu when operated with a novel segmented rod atomiser (86/C649), Extension of the dynamic range of analytical calibration graphs has been achieved in Zeeman-effect AAS by making absorbance measurements at two different field strengths, maximum and intermediate (86/C654).Results were demon- strated for Ag at 328.1 nm and showed a maximum extension of about a factor of five. A number of limitations were indicated including increased curvature during the inter- mediate field strength measurements due to variations in the absorption profile over the lamp emission profile. Developments in coherent forward scattering have been limited to two new instrument systems (86/C526, 86/C782, 86/C840). Both spectrometers are designed for multi-element analysis, one achieving background correction by polarisation modulation (86/C526). A portable instrumental system has been developed for the simultaneous determination of Ag, Al, Cr, Cu, Fe, Mg, Ni, Si and Ti as wear metals in used engine oils (S/C250).The system was designed to fit into two aluminium suitcases. A short focal length (20 cm) poly- chromator was used with two multi-element HCLs and a commercial graphite furnace. The most versatile approach to simultaneous multi-element atomic absorption analysis with electrothermal atomisation is based on the use of a continuum light source and a high-resolution polychromator. The flexibility of this system and the accuracy of the wavelength modulation background correction facility have been demonstrated by the determi- nation of seven metals, Al, Co, Cr, Mn, Mo, Ni and V in blood serum (S/194, 86/C520, 86/C779). In this instance, Mg(NO& was used as a combined ashing aid and matrix modifier, but the selected ashing temperature of 1300 "C precluded the determination of Pb and Sn.The sensitivity and wide dynamic range of this system allowed calibration ranges with the furnace covering 0.1-100000 ng ml-1 and this often avoided the necessity for different sample dilutions for different elements. The potential of probe atomisation for simul- taneous multi-element analysis has been demonstrated (86/665), and the use of slurry sample introduction has been reported (86/C904). A single-channel continuum-source AAS system has also been described (S/C510, 86/69, 861204, 86/C7807 8611273). An Apple microcomputer was used to control data acquisition and to perform data processing, and it controlled the wavelength modulation background correction facility essential for graphite furnace atomisation.The effi- ciency of this form of background correction has been compared with current systems based on D2-arc and the Zeeman effect with favourable results (86/C780). There appears to be renewed interest in the measurement of atomic emission signals using the graphite furnace as the emission source. Both the wavelength modulated instruments described above for multi-channel and single-channel opera- tion have been utilised with equal convenience in this mode of operation. Instruments based on the echelle spectrometer have been used for the determination of A1 (86/197) and Mn (86/211) in biological materials. The A1 procedure was based on a novel constant-temperature graphite furnace coupled to a computer controlled emission spectrometer system with wavelength modulation background correction (86/197, 86/C510).Detection limits for this system for a wide range of elements were comparable to previously reported best values using platform or probe atomisation. Papp and co-workers in Hungary have reported a number of interesting studies of furnace atomic emission (9842, 86/ C288, 86K295). A comparison of the SNR obtained with different graphite tubes and different modified surfaces provided some interesting data (S/842). Apparently the best SNR and lowest mass loss were observed with a graphite tube coated with HfC and subsequently coated with pyrolytic graphite. Low detection limits in the 0.042-35 pg range were reported for ten elements by means of atomic emission measurements with a tungsten microtube atomiser (921 1).A standard AAS instrument system has also been used for the furnace emission determination of Li in silicate rocks (S/C254). Simultaneous multi-element analysis has also been demon- strated in an electrothermal atomiser using a FANES system (86/C507). Furnace atomisation non-thermal excitation spec- trometry has been developed by Falk and co-workers over several years (see ARAAS, 1982, 12, ref. 425 and ARAAS, 1984, 14, 47). In the present work, the FANES source was operated with a 1.5-m Rowland circle polychromator with up to ten spectral output channels (86/C507). The direct analysis of both solid and solution samples was demonstrated. The interference of the inorganic salts in a typical biological matrix on Cd were negligible in a FANES system (861C627).A standard additions procedure was however required for the determination of Cd in whole blood. It appears that the organic and/or inorganic constituents may affect the discharge and hence modify the excitation conditions. Matrix influences of this type are greatly reduced when higher ash temperatures can be used to remove a major portion of the matrix. The FANES system has also been coupled to the microcomputer controlled wavelength modulation system mentioned above (86/204), and this has allowed both background corrected atomic emission and continuum source atomic absorption measurements to be made with the FANES atomiser (86/C781). Atomic fluorescence measurements with electrothermal atomisers are largely restricted to use with laser-excitation sources and are covered in section 3.5.Most use electrother- mal atomisers of conventional design, but a novel tungsten- spiral atomiser has been described for LAFS measurements (86/C528).152R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 5. CHEMICAL VAPOUR GENERATION The chemical generation of arsine for analytical measurement was originally developed by Marsh (see Edin. Phil. J . , 1836, 21,229) who said “Being thus brought to the gaseous state, the arsenic would spontaneously (so to speak) separate itself from the liquor in which it was before dissolved, and might be collected for examination by means of any common gas apparatus . . .”. Towards this end there appeared an enormous volume of relevant works in the review period which indicated the degree of acceptance that chemical vapour sample introduction enjoys in analytical atomic spectroscopy.Many of these reports described applications. 5.1. Hydride Generation Following the extensive mechanistic studies by Welz and Melcher (see ARAAS, 1983, 13, 46 and 1984, 14, 49), Agterdenbos et al. (86/119, 86/C604, 86/785) carried out further investigations in this area. Their apparatus allowed for the introduction of constant known flow-rates and concen- trations of H2Se, AsH3, Nz, H2 and other species into an electrically heated quartz tube atom cell. This cuvette had a constant and known temperature along the optical absorption path. Thermodynamic calculations on the decomposition of H2Se and AsH3 predicted the formation of Se2 and As2, which were observed under different conditions for the respective hydrides.Their work both supported and extended the investigations of Welz and Melcher with respect to the role of hydrogen radicals. Dittrich and Mandry (86/C787) investi- gated gas phase interferences observed in the atomisation of generated hydrides. They compared the atomisation efficien- cies of a 10-cm path length electrothermal graphite-paper atomiser with those of a conventional quartz tube by AAS measurements. For pure solutions of hydride forming ele- ments, no difference was observed in either of the AAS signals at 1000°C in the quartz tube or at 2000°C in the graphite- paper tube. However, for analyte solutions that contained other hydride forming elements, the graphite-paper tube atomiser gave 10-1 000 times improved sensitivity compared with the quartz tube.Thermodynamic and spectroscopic measurements showed that molecules such as AsBi and AsSe existed and were stable at 1000 “C, but not at 2000 “C. Brovko et al. (S/218) and Sturgeon etal. (86/720,86C/786) reported the adsorption of gaseous hydrides on activated charcoal surfaces inside a graphite furnace atomiser. This technique demon- strated the advantage of a simple pre-concentration step prior to atomisation at 2200°C. Another report described a recirculating gas atom cell for hydride generation AAS and in it the author discussed the kinetics of arsine decomposition, assuming these to be of a thermal nature, which was in sharp contrast to the work mentioned above (86/C607). Krivan et al. (86/62) employed radiotracer experiments with 75Se to obtain information on the possible sources of error present in all stages of the determination of Se in environmental samples with hydride generation AAS. Satisfactory recoveries were obtained from all stages, but degradation of signal occurred due to the back-oxidation of Se(1V) to Se(V1) after the prior reduction step as a result of the residual CIz produced. The problem of interferences from concomitant matrix elements during either the generation or atomisation stages has again received attention. Bye (S/1105) used electrolytic removal of Cu to alleviate its interference on the generation of H2Se. Ikeda (86/410) used an on-line chelating resin contain- ing iminodiacetate groups to remove transition metals inter- fering with the determination of Se in copper alloys and nickel sponge. Castillo et al. (86/668, 86/742) published data con- cerned with interferences on the generation of PbH4 in the presence of a variety of ionic species and with the use of oxidising agents to compensate for these interferences. In certain sections of this work, the results presented appeared to be insufficient to support the conclusions drawn. Yamamoto et al. (S/659) proposed a method for the elimination of metal interferences by using dilute solutions of NaBH4, which they successfully applied to the determination of As in copper, nickel and steel. Removal of interferences has been ac- complished in a variety of matrices using so-called masking agents such as thiourea (S/175), citric acid (S/1100), 1 , l O - phenanthroline (86/244), thiosemicarbazide (86/683) and sulphanilamide (86/1437). Optimisation of a hydride generation accessory for ICP- AES was reported by Parker et al. (S/638). They used a Simplex algorithm on four plasma operating parameters and two generation parameters. The latter two variables were also mapped using factorial design, regression analysis and canoni- cal analysis to obtain precise positions of the optima. In another report, Dedina (86/783) used an optimisation expres- sion that divided operational parameters into two classes: (i) independent variables such as apparatus dimensions and gas flow-rates and (ii) atomisation and generation efficiencies and rate constants. The expression predicted observed signal responses quite accurately. Wang and Barnes (86/C1129) discussed, in theoretical and experimental terms, the effect of pH on hydride generation. Their calculated and experimental optimum pH ranges were in good agreement, but there were no interfering species and only one acid present. Gong et al. (86/1309) investigated the effect of temperature on generating solutions. Welz et al. (S/494, S/590) systematically evaluated digestion procedures applied to body fluids and marine biological samples for the determination of As, Hg and Se. They compared the relative merits, with respect to analytical accuracy, of three decomposition procedures: (i) nitric acid in a PTFE bomb, (ii) nitric - sulphuric - perchloric acid mixture and (iii) oxygen ashing, finding that it was elemental depen- dent. van der Veen et al. (86/88) compared ten digestion techniques for the determination of As in soils, three of which were rejected on the basis of poor recovery. The determination of the various chemical forms of the hydride forming elements was the subject of a number of papers. Amanka and Fasching (S/836) determined As(II1) and As(V) levels in sea water by extraction of the former into APDC and total arsenic determination on a non-extracted sample. Selenium(1V) and Se(V1) were determined in sedi- ments and planktonic material by selective extraction and digestion (86/1286) together with organic and inorganic species (S/117, S/l80). Hydride generation provided a suitable means of sample pre-treatment (S/C276, S/809) for the gas-chromatographic separation of non-volatile tin and lead compounds. The organo-substituted metal hydrides were trapped and separated on simple columns prior to AAS detection. Hydride generation proved to be an invaluable tool for interfacing HPLC with atomic spectrometry, particularly in the field of environmental analysis (S/794, 86/14, 86/C142). Various papers (S/501, S/901, S/1101, S/1103, 86/C606) reported the use of continuous “suction-flow” or flow injection hydride generation, the former appeared to be a variation on the latter. While useful applications of FI, they provided no innovative advances with respect to the original work of Thompson et al. (see ARAAS, 1978,8,9). A number of papers (SlC695, S/845, 86/C784, 86/1009) described the performance characteristics and automation of commercially available hydride generation accessories. Other papers on this topic are S/146, 86/C277. 5.2. Mercury Determination As with section 5.1 a large majority of the papers received during the past review year were related to environmental applications. There were however, several reports that merit further discussion.JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 153R Wigfield and Perkins (S/194, 86/1332) investigated the chemical behaviour of Hg(1) ions in solution with respect to the disproportionation equilibrium, viz. At concentrations of Hg(1) of between 15 and 130 pg l-l, under non-reducing conditions, they observed a cold vapour atomic absorption signal (CV-AAS) that was entirely due to dispro- portionation. The cold vapour signal was pH dependent and at low hydrogen ion concentration approached the value expec- ted from complete disproportionation. The results obtained have implications in both sample handling and standardisation procedures. Didorenko et al. (S/667) reported that the interference observed on Hg in CV-AAS, due to the presence of selenium and tellurium, was related to the formation of HgSe and HgTe molecules. They suggested that this inter- ference could be minimised either by using minute amounts of SnC12 or employing dimethylaminoborane as a reductant. Hgz'+ $ HgO + Hg2+ An interesting calibration technique was revived by Dumarey et al. (86/411), which involved the direct syringe injection of Hg saturated air into the atom cell. These workers claimed an over all relative precision of better than 0.01 in the range 1-100 ng of Hg under optimised conditions. In a separate study (86/964) they evaluated the collection and desorption efficiency of activated charcoal, silver and gold for CV-AAS. In an optimisation study (S/226) on non-dispersive AFS and cold vapour Hg generation, the authors claimed a remarkable detection limit of 2 ng I-'. Some minor develop- ments in instrumentation for CV-AAS have been described. Einarssan et al. (S/2) reported the use of a computerised automated device designed for the analysis of small volumes of body fluids. Hinten et al. (YC350) described the modification of a commercial instrument to perform on line Hg monitoring using CV-AAS from two locations on a process stream at 15-min intervals. LOCATION OF REFERENCES The references cited in this Update have been published as follows: Sll-Sl1234, J . Anal. At. Spectrom., 1986, Supplement, 1S-49S. 8611-861265, J . Anal. At. Spectrom., 1986, 1(1), 19R-28R. 86/26&86/709, J . Anal. At. Spectrom., 1986, 1(2), 45R-59R. 86/71&86/1030, J . Anal. At. Spectrom., 1986, 1(3), 75R-85R. 8611031-86/1460, J . Anal. At. Spectrom., 1986, 1(4), 107R-120R. 8611461-86/1466, J. Anal. At. Spectrom., 1986, 1(5), 155R.154R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 Glossary of Abbreviations Whenever suitable, elements may be referred to by their chemical symbols and compounds by their formulae. The following abbreviations are used extensively in the Atomic Spectrometry Updates. a.c. AA AAS AE AES AF AFS APDC ASV CMP CRM cw d.c. DCP DMF DNA EDL EDTA ETA FAAS FAES FAFS FI GC GDL HCL h.f. HPLC IBMK alternating current atomic absorption atomic absorption spectrometry atomic emission atomic emission spectrometry atomic fluorescence atomic fluorescence spectrometry ammonium pyrrolidinedithiocarbamate (ammonium tetramethylenedithio- carbamate) anodic-stripping voltammetry capacitively coupled microwave plasma certified reference material continuous wave direct current d.c. plasma N, N-dimethylformamide deoxyribonucleic acid electrodeless discharge lamp ethylenediaminetetraacetic acid electrothermal atomisation flame AAS flame AES flame AFS flow injection gas chromatography glow discharge lamp hollow-cathode lamp high-frequency high-performance liquid chromatography isobutyl methyl ketone (4-methylpentan- 2-one) ICP IR LC LTE MECA MIP MS NAA NaDDC NTA OES PMT p.p.b. p.p.m. PTFE r.f. REE RM RSD SBR SEM SNR SSMS TCA TLC TOP0 u.h.f. uv VDU vuv XRF inductively coupled plasma infrared liquid chromatography local thermal equilibrium molecular emission cavity analysis microwave-induced plasma mass spectrometry neutron-activation analysis sodium diethyldithiocarbamate nitrilotriacetic acid optical emission spectrometry photomultiplier tube parts per billion parts per million polytetrafluoroethylene radiofrequency rare earth element reference material relative standard deviation signal to background ratio scanning electron microscopy signal to noise ratio spark-source mass spectrometry trichloroacetic acid thin-layer chromatography trioctylphosphine oxide ultra-high-frequency ultraviolet visual display unit vacuum ultraviolet X-ray fluorescence

ISSN:0267-9477    

DOI:10.1039/JA986010121R

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 155R ATOMIC SPECTROMETRY UPDATE REFERENCES The address given in a reference is that of the first named author and is not necessarily the same for any co-author. 861 8 61 461. 462. 8611463. 8611 464. 8611465. 8611 466. 8611467. 8611 468. 8611469. 86/ 1470, 8611471. Krull, I. S., Panaro, K. W., Trace analysis and speciation for methylated organotins by HPLC - hydride genera- tion - direct current plasma emission spectroscopy (HPLC - HY - DCP), Appl. Spectrosc., 1985, 39, 960. (Barnett Inst., Northeast. Univ., Boston, MA 02115, USA). Yan, D. R., Stumpp, E., Schwedt, G., Comparison of ion chromatography and atomic absorption spectrometry for metal ion analysis in wine and fruit juices, Fresenius Z . Anal. Chem., 1985, 322, 474.(Central South Coll. Min. Metall., Changsha, China). Algeo, J. D., Heine, D. R., Phillips, H. A., Hoek, F. B. G., Schneider, M. R., Freelin, J. M., Denton, M. B., On the direct determination of metals in lubricating oils by ICP, Spectrochim. Acta, Part B , 1985,40, 1447. (Dept. Chem., Univ. Arizona, Tucson, AZ 85721, USA). Mitchell, P. G., Ruggles, J. A., Sneddon, J., Radziemski, L. J., Direct determination of copper in solids and ores by laser ablation - direct current argon plasma emission spectrometry, Anal. Lett., 1985, 18 (A14), 1723. (Dept. Chem., New Mexico State Univ., Las Cruces, NM Nerin, C., Cacho, J., Garnica, A., Indirect determination of bromhexine by atomic absorption spectrophotometry, Anal. Lett., 1985, 18 (B15), 1887. (Departamento de Quimica, Escuela TCcnica Superior de Ingenieros Indus- triales Universidad de Zaragoza, Zaragoza, Spain).Taylor, P., Dams, R., Hoste, J., The determination of cadmium, chromium, copper, nickel and zinc in city waste incinerator ash using inductively coupled plasma atomic emission spectrometry, Anal. Lett., 1985, 18 (A19), 2361. (Inst. Nuclear Sci., State Univ. Gent, Proeftuinstraat 86, 9000 Ghent, Belgium). Cheng, C. J., Akagi, T., Haraguchi, H., Simultaneous multi-element determination of trace metals in sea water by inductively coupled plasma emission spectrometry using chelating resin column pre-concentration, B u f f . Chem. SOC. Jpn., 1985, 58, 3229. (Dept. of Chem., Fac. Sci., Univ. Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113, Japan). Ping, L., Lei, W., Matsumoto, K., Fuwa, K., A study of the inter-elemental effect in the carbon furnace atomic absorption spectrometry of selenium and mercury in biological samples by the palladium addition method, Bull.Chem. SOC. Jpn., 1985,58,3259. (Dept. Chem., Fac. Sci., Univ. Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan). Morris, B. W., Hardisty, C. A., McCann, J. F., Kemp, G. J., May, T. W., Evidence of Cr toxicity in a group of stainless-steel welders, At. Spectrosc., 1985, 6, 149. (Clin. Chem. Dept., Northern General Hospital, Sheffield S5 7AU, UK). Castillo, J. R., Mir, J. M., Bendicho, C., Martinez, C., Determination of B in vegetal matter by AAS using direct atomisation of methyl borate as volatile phase, At. Spectrosc., 1985, 6, 152. (Dept. Anal. Chem., Sci. Fac., Univ.Zaragoza, Zaragoza, Spain). Slavin, W., Carnrick, G. R., A survey of applications of the stabilised temperature platform furnace and Zeeman correction, At. Spectrosc., 1985, 6, 157. (Perkin-Elmer Corp., 761 Main Ave., Norwalk, CT 06859, USA). 88003-0004, USA). 8611472. Blust, R., Van der Linden, A., Decleir, W., Microwave- aided dissolution of a biological matrix in AAS sample cups prior to graphite furnace analysis, At. Spectrosc., 1985,6,163. (Lab. for Biochem. and Gen. Zoology, Univ. Antwerp (RUCA), Groenenborgerlaan 171, B-2020 Ant- werp, Belgium). Roy, N. K., Das, A.-K., Ganguli, C. K., Determination of Sn in rocks and minerals by chelate extraction AAS, At. Spectrosc., 1985, 6, 166. (Chem. Lab., Geol. Survey of India, 27 J. L. Nehru Rd., Calcutta 700016, India).8611473. Papers 861C1474-86IC1602 were presented at the 1986 Pittsburgh Conference and Exposition on Analytical Chemistry and Applied Spectroscopy, Atlantic City, NJ, USA, 10th-14th March, 1986. 861C1474. Taylor, H. E., Inductively coupled plasma mass spec- trometry for the quantitative analysis of natural waters, (US Geol. Survey, 5293 Ward Rd., MS 407, Arvada, CO 80002, USA). 861C1475. Paulsen, P. J., Applications of ICP-MS to isotope dilution analysis of standard reference materials, (Inorganic Anal. Res. Div., Cent. Anal. Chem., National Bureau of Standards, Gaithersburg, MD 20899, USA). 86/C1476. Hausler, D. W., Applications of ICP-MS in a petroleum laboratory, (Phillips Petroleum Co., Phillips Res. Cent., Bartlesville, OK 74004, USA). 86lC1477. Fassel, V.A., ICP-MS: past, present, future, (Ames Lab.-USDOE and Dept. Chem., Iowa State Univ., Ames, IA 5001 1, USA). 861C1478. Houk, R. S., Fundamental principles of and instrumenta- tion for ICP-MS, (Ames Lab.-USDOE and Dept. Chem., Iowa State Univ., Ames, IA 50011, USA). 861C1479. Hieftje, G. M., New laser-based procedures in chemical analysis, (Dept. Chem., Indiana Univ., Bloomington, IN 47405, USA). 861C 861C 480. Arrowsmith, P., Boorn, A. W., Doherty, W., Analysis of solid samples by laser ablation ICP-MS, (SCIEX, 55 Glen Cameron Rd., Unit 202, Thornhill, ON L3T IP2, Canada). 481. Matthews, E. W., Hooper, R. C., Aqueous total chro- mium: oxidation by cerium(1V); chelation, extraction and determination of chromium and six other trace metals by flame AAS, (Natl.Aquascience, PO Box 768042, Ros- well, GA 30076, USA). 86/C1482. Denton, M. B., Smith, T. R., Bilhorn, R. B., Sweedler, J. V., Plasma emission as an element selective detector for liquid chromatography, (Dept. Chem., Univ. Arizona, Tucson, AZ 85721, USA). 861C1483. Fulford, J. E., Arrowsmith, P., Boorn, A. W., Douglas, D. J., Gillson, G. R., Instrumental factors influencing the analytical performance of ICP-MS, (SCIEX, 55 Glen Cameron Rd., Unit 202, Thornhill, ON L3T 1P2, Canada). 861C1484. Quan, E. S. K., Liversage, R., Boorn, A. W., Gillson, G. R., Progress in elemental and isotopic analyses by ICP- MS, (SCIEX, 55 Glen Cameron Rd., Unit 202, Thornhill, ON L3T 1P2, Canada).156R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 86/C 1485.Douglas, D. J., Quan, E. S. K., A comparison of peak hopping and multi-channel scaling modes of data acquisi- tion for isotope ratio determinations by ICP-MS, (SCIEX, 55 Glen Cameron Rd., Unit 202, Thornhill, ON L3T 1P2, Canada). 86lC1486. Wilson, D. A., Vickers, G. H., Mitchell, J. C., Rayson, G. D., Hieftje, G. M., Hofler, K. J., Precision isotope-ratio determinations on a new ICP-MS system, (Dept. Chem., Indiana Univ., Bloomington, IN 47405, USA). 861C1487. Faske, A. J . , Browner, R. F., Liquid chromatography and flow injection coupling for ICP-MS, using a monodisperse aerosol generation interface (MAGIC-LC - ICP - MS), (Sch. Chem., Georgia Inst. Technol., Atlanta, GA 30332, USA). 86/C1488. Vickers, G. H., Wilson, D. A., Hieftje, G. M., Hofler, K. J., The effect of plasma-generator frequency on induc- tively coupled plasma mass spectrometry, (Dept.Chem., Indiana Univ., Bloomington, IN 47405, USA). 86lC1489. Hutton, R. C., Cantle, J. E., Kelley, D. E., An examina- tion of apparent matrix effects in ICP-MS analysis, (VG Instruments Inc., 300 Broad St., Stamford, CT 06901, USA). 861C1490. Wohlers, C. C., Schleicher, R. G., Sainz, M. A., Nygaard, 86/C 86/C D. D., Reduction of interferences in inductively coupled plasma electrothermal vaporisation analysis (ICP-EVA), (Allied Analytical Systems, 590 Lincoln St., Waltham, MA 02254, USA). 491. Ono, A,, Chiba, K., Saeki, M., Fundamental studies on direct analysis of molten iron with inductively coupled plasma emission spectrometry, (R & D Lab.-I, Nippon Steel Corp., 1618 Ida, Nakahara-ku, Kawasaki 211, Japan).492. Schmertmann, S. M., Long, S. E., Browner, R. F., Fundamental studies of a graphite rod electrothermal vaporisation device for sample introduction in inductively coupled plasma atomic emission spectroscopy, (Sch. Chem., Georgia Inst. Technol., Atlanta, GA 30332, USA). 86/C1493. Barnes, R. M., Bakowska, E., Chen, Z. C., Chung, Y. S., Horvath, Z. Z., Kargacin, M., Wang, X., Sample prepara- tion and presentation in inductively coupled plasma spectrochemistry, (Univ. Massachusetts, Dept. Chem., GRC Towers, Amherst, MA 01003-0035, USA). 86/C 86/C 494. Hieftje, G. M., Fundamental investigations and instrumen- tal developments in ICP spectrochemistry, (Dept. Chem., Indiana Univ., Bloomington, IN 47405, USA). 495. Patel, B. M., Winefordner, J.D., Spectral characteristics of a glow discharge atomisation source for atomic fluores- cence spectrometry, (Dept. Chem., Univ. Florida, Gainesville, FL 3261 1, USA). 86/C1496. Goulter, J. E., Durrant, K., Cooley, B. W., The applica- tion of glow discharge optical emission spectroscopy to the elemental depth profiling of coated steels, (Applied Research Laboratories Inc., 9545 Wentworth St., Sun- land, CA 91040, USA). 86/C1497. Winefordner, J. D., Fluorescence measurements in ICP, (Dept. Chem., Univ. Florida, Gainesville, FL 32611, USA). 86/C1498. Marcus, R. K., Harrison, W. W., Hollow cathode plume atomic emission analysis of compacted samples, (Dept . Chem., Univ. Virginia, Charlottesville, VA 22901, USA). 86/C1499. Horlick, G., Tan, S. H., Vaughan, M.A., Lam, J., Shao, Y ., The analytical characteristics and capabilities of inductively coupled plasma mass spectrometry, (Dept . Chem., Univ. Alberta, Edmonton, Alberta T6G 2G2, Canada). 86/C1500. Lovett, R. J., Analyte transport in an ICP, (Dept. Chem., North Dakota State Univ., Fargo, ND 58105, USA). 86/C1501. Lysakowski, R. S., Jr., Dessy, R. E., Long, G. L., Laser-induced fluorescence in a microwave induced plas- ma-LIF-MIP, (Dept. Chem., Virginia Polytechnic Inst. and State Univ., Blacksburg, VA 24061. USA). 86/C1502. Perkins, L. D., Lysakowski, R. S., Jr., Long, G. L., The application of atomic fluorescence spectrometry to GC- MIP determinations, (Dept. Chem., Virginia Polytechnic Inst. and State Univ., Blacksburg, VA 24061, USA). 86/C1503. Goldberg, J., Carney, K., Allston, R., Imploding thin film atom cells for the direct analysis of solids, (Univ.Vermont, Dept. Chem., Burlington, VT 05405, USA). 86/C1504. Atkins, J. W., Smith, P. B., The analysis of complex alloyed steels using a glow discharge lamp optical emission spectrometer, (Hilger Analytical Ltd., Westwood, Mar- gate, Kent, UK). 86/C1505. Pearson, K. H., Schermaier, A. J., Tytko, S. A., Assess- ment of levels of metal contamination from blood collec- tion tubes, (Dept. Chem., Cleveland State Univ., Cleve- land, OH 44115, USA). 86K1506. Rayson, G. D., Parisi, A. F., Hieftje, G. M., Spatial and temporal investigation of atomisation and molecular recombination mechanisms within a power modulated ICP, (Dept. Chem., Indiana Univ., Bloomington, IN 86/C1507.Marshall, K. A., Hieftje, G. M., Determination of electron concentrations and energies in an ICP via multi-channel Thomson scattering, (Dept. Chem., Indiana Univ., Bloomington, IN 47405-4001, USA). 86/C1508. Batie, W. C., Sellek, D. A., ICP-economic factors-a 40 MHz, low-flow, low-power plasma, (Labtest Equipment Co., 11828 La Grange Ave., Los Angeles, CA 90025, USA). 861C1509. Walker, Z. H., Blades, M. W., Level population measure- ments on analyte atom and ion excited states in the inductively coupled plasma, (Dept. Chem., 2036 Main Mall, Univ. British Columbia, Vancouver, BC V6T 1Y6, Canada). 86/C1510. Hubert, J., Tra, H. V., Baudais, F. L., Detection of atomic emission in the ultraviolet using a Fourier transform spectrophotometer, (Chem. Dept., Univ. Montreal, PO Box 6828, Station A, Montreal, Quebec H3C 3J7, Canada).86lC1511. Fogg, T. R., Li, K. P., Hilderbrand, K., 3 Dimensional emission profiles of an ICP, (Science Applications Interna- tional Corp., 476 Prospect St., La Jolla, CA 92038, USA). 86/C1512. Hites, B., Mitchell, J., Parisi, A. F., Rayson, G. D., Hieftje, G. M., An integrated tool for studying 2-dimen- sional transient images of various spectroscopic sources, (Dept. Chem., Indiana Univ., Bloomington, IN 47405- 4001, USA). 47405-4001, USA). I 86lC1513. Monnig, C. A,, Marshall, K. A., Rayson, G. D., Hieftje, G. M., Spatially resolved studies of the inductively coupled plasma via tomographic reconstructions-I. Theory, (Dept. Chem., Indiana Univ., Bloomington, IN 47405- 4001, USA). 861C1514. Marshall, K.A., Monnig, C. A., Rayson, G. D., Hieft-ie, G. 86/C 86/C M., Studies of the inductively coupled plasma via iomo- graphic reconstruction-11. Experimental system, (Dept. Chem., Indiana Univ., Bloomington, IN 47405-4001, USA). 515. Blades, M. W., Burton, L. L., Computer simulation of ICP spectra-a new tool for the study of excitation, emission and line overlap, (Dept. Chem., 2036 Main Mall, Univ. British Columbia, Vancouver, BC V6T 1Y6, Canada). 516. Voth-Beach, L. M., The determination of trace elements in biological samples by atomic absorption techniques, (Varian Instrument Group, AARC, 205 W. Touhy Ave., Park Ridge, IL 60068, USA).JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL. 1 157R 86/C1517. Seward, D. R., O’Haver, T. C., Harnly, J.M., High-speed data acquisition for atomic spectroscopy using a minicom- puter, (Chem. Dept., Univ. Maryland, College Park. MD 20742, USA). 86/C1518. Churella, D. J., Gilbert, T. R., Determination of trace elements in used lubricating oils by graphite filament plasma emission spectrosyopy, (Dept. Chem., North- eastern Univ., Boston, MA\02115, USA). 86/C1519. Ivancic, W. A., Grieser, D. R., Corliss, J. M., Barnes, R. H., Optical spectroscopic studies in a pulse combustion furnace, (Battelle, 505 King Ave., Columbus, OH 43201, USA). 86iC1520. Gilbert, T. R., Sandoval, J., Yurko, R. J., Direct determination of trace elements in viscous fluids by ARC emission spectroscopy using a novel rotating disk elec- trode, (Dept. Chem., Northeastern Univ., Boston, MA 02115, USA).86/C1521. Kerkhoff, J., Genna, J. L., Burr, R., Analysis of seleniu- m(1V) and selenium(V1) with a continuous flow induc- tively coupled plasma emission spectrometer system, (Alcoa Technical Center, Alcoa Center, PA 15069, USA). 86C1.522. Faske, A. J., Browner, R. F., Performance of a monodis- perse aerosol generator (MAG) in ICP-OES, (Sch. Chem., Georgia Inst. Techno]. , Atlanta, GA 30332, USA). 86iC1523. Algeo, J. D., Childers, C. M., Goulter, J. E., Radey, T. K., Rentner, J. R., Routh, M. W., Satogami, S., Tasker, D. B., Tikkanen, M. W., Wilhelrn, J. R., ICP-Fourier transform spectrometry: analytical tool or scientific curiosity?, (Applied Research Laboratories, Inc., 9545 Wentworth St., Sunland. CA 91040, USA). 86/C1524. Olesik, J. W., Olesik, S. V., Supercritical fluid-based sample introduction for inductively coupled plasma atomic spectroscopy, (Dept.Chem., Venable and Kenan Labora- tories, Univ. North Carolina, Chapel Hill, NC 27514, USA). 86/C1525. Gentry, J. S., Boss, C. B., Investigations on analyte transport in a direct current plasma, (Dept. Chem., North Carolina State Univ., Box 8204. Raleigh, NC 276958204, USA). 86/C1526. Winn, D. H., Koropchak, J. A., Thermospray sample introduction for atomic spectrometry, (Dept. Chem. Biochem., Southern Illinois Univ., Carbondale, IL 62901, USA). 86/C1527. Borst, J. E., Goulter, J. E., Tasker, D. B., Characterisa- tion and application of a new ultrasonic nebuliser for the ICP, (Applied Research Laboratories Inc., 9545 Went- worth St., Sunland, CA 91040, USA). 86/C1528.Miller, J. R., Long, S. E., Browner, R. F., In search of the 86iC 86/C optimum droplet- size for inductively coupled plasma emission spectrometry, (Sch. Chem., Georgia Inst. Tech- nol., Atlanta. GA 30332, USA). 529. Legere, G., Burgener, P., Optimisation of aerosol baffle and chamber when used with the Legere nebuliser, (Technical Service Lab., 1301 Fewster Drive, Mississauga, Ontario L4W 1A2, Canada). 530. Dokiya, Y., Yoshirnura, E., Toda, S., Determination of alkaline earth metals in rain samples by ICP emission spectrometry, (Meteorol. Res. Inst., Nagamine, Yatabe, Tsukuba, Ibaraki 305, Japan). 86/C1531. Pfeil, D. L., Schleicher, R. G., Smith, S. B., Jr., Computer control of graphite furnace atomic absorption parameters, (Allied Analytical Systems, 590 Lincoln St., Waltham, MA 02154, USA).86C1532. Tarter, J. G., Maketon, S., Ion chromatography with indirect atomic spectrophotometric detection, (Dept. Chem., North Texas State Univ., Denton, TX 762034068, USA). 86X1.533. Sainz, M. A., Schleicher, R. G., Belmore, R. J., Beaty, J. S., Smith, S. B., Jr., In situ molten metal analysis, (Allied Analytical Systems, 590 Lincoln St., Waltham, MA 02154, USA). 86iC1.534. Edwards, A. G., Boss, C. B., An investigation of the signal enhancing mechanisms in tandem flame spectrometry, (North Carolina State Univ., Dept. Chem., Box 8204, Raleigh, NC 276958204, USA). 86/C1535. Satzger, R. D., Fricke, F. L., Caruso, J. A., Elemental analysis with a quadrupole mass spectrometer using a moderate power microwave induced plasma as an ion source, (Elemental Analysis Res.Cent., FDA, 1141 Central Parkway, Cincinnati, OH 45202, USA). 861C1536. Benedetti, M. F., Kersabiec de, A. M., Trace elements determination in geological samples using ICP source spectrometry, (Laboratoire de GCochimie et MCtallogCnie (UA CNRS 196), Universitk Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France). 86/C1537. Miller-Ihli, N. J., Comparison of ashing techniques for the preparation of biological samples for AAS, (Nutrient Composition Lab., BHNRC, Agricultural Res. Service, US Dept. of Agriculture, Beltsville, MD 20705, USA). 861C1538. McCreary, T. W., Yoon, R., Long, G. L., The effect or organic gases on molecular formation reactions in the DCP, (Dept. Chem., Virginia Polytechnic Inst., State Univ., Blacksburg, VA 24061, USA).86/C1539. Lysakowski, R. S., Jr., Dessy, R. E., An improved microwave induced nitrogen plasma at 1 atmosphere, (Dept. Chem., Virginia Polytechnic Inst., State Univ., Blacksburg, VA 24061, USA). 86/C1540. Delles, F. M., Brodie, K. G., Application of a centralised control graphite furnace AA spectrophotometer to the measurement of trace metals in foods, (Varian Instrument Group, AARC, 205 W. Touhy Ave., Park Ridge, IL 60068, USA). 86/C1541. Kane, J. S., McClain, R., Graphite furnace atomic absorption determination of trace elements in massive sulphides, (US Geological Survey, Reston, VA 22092, USA). 86/C1542. Schlemmer, G., Welz, B., Determination of selenium in biological materials using graphite furnace AAS with Zeeman-effect background correction, (Dept .Applied Research, Bodenseewerk Perkin-Elmer & Co. GmbH, D-7770 Uberlingen, FRG). 86/C1543. Carnrick, G. R., Barnett, W. B., Slavin, W., Factors affecting graphite furnace characteristic mass, (Perkin- Elmer Corp., 901 Ethan Allen Highway, Ridgefield, CT 06877, USA). 86/C1544. Monnig, C. A., Hieftje, G. M., Coherent forward scatter- ing of laser radiation from a graphite tube atomiser, (Dept. Chem., Indiana Univ., Bloomington, Indiana 47405-4001, USA). 86/C1545. Holcornbe, J. A., Black, S. S., Riddle, M. R., Monte Carlo simulation of processes in graphite furnace atomisation, (Dept. Chem., Univ. Texas at Austin, Austin, TX 78712, USA). 86iC1.546. Harnly, J. M., Peak parameters as diagnostics for carbon furnace AAS, (US Dept. Agriculture, Agricultural Res.Service, Beltsville Human Nutrition Res. Center, Nutrient Composition Lab., Building 161, BARC-E, Beltsville, MD 20705, USA). 86X1.547. Schlemmer, G., Welz, B., Tube materials for electrother- mal atomisation - lifetime and analytical performance, (Dept. Applied Research, Bodenseewerk Perkin-Elmer & Co. GmbH, D-7770 Uberlingen, FRG). 86iC1548. Droessler, M. S., Holcombe, J. A., Spectral interferences and chemical interactions associated with selenium deter- minations by GFAA, (Dept. Chem., Univ. of Texas at Austin, Austin, TX 78712, USA).158R JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 86/C1549. Pitluck, M. R., Haworth, D. T., Pollard, B. D., Metal - fulvic acid stability constant determinations by flow-injec- tion analysis atomic absorption spectroscopy, (Chem.Dept., Marquette Univ., 535 N. 14th St., Milwaukee, WI 53233, USA). 86/C1550. Kane, J. S., Dorrzapf, A. F., Jr., Crandell, W., Analysis of hydrothermal sulphide deposits using inductively coupled argon plasma atomic emission spectrometry, (US Geolog- ical Survey, Reston, VA 22092, USA). 86/C1551. Patel, B. K., Single laboratory evaluation of inductively coupled plasma optical emission method 6010, (Lockheed Engineering and Management Services Co., Las Vegas, NV 89109, USA). 86/C1552. Tikkanen, M. W., Algeo, J. D., Goulter, J. E., Routh, M. W., New analytical strategies using a practical inductively coupled plasma Fourier transform spectrometer, (Applied Research Laboratories Inc., 9545 Wentworth St., Sun- land, CA 91040, USA).86/C1553. Rubright, L. A,, Centrella, K. R., Analysis of antimonial battery alloys by DCP, (General Battery Corp., Technical Center, PO Box 1262, Reading, PA 19603, USA). 86/C1554. Rutstrom, D. J., Flinchbaugh, D. A,, Determination of overlay and alloy layer compositions of A1 - Zn coatings, (Corporate Technology, Bethlehem Steel Corp., Beth- lehem, PA 18017, USA). 86/C1555. Dalton, J. I., A general fusion - ICP method for the analysis of bauxites, bayer muds and related materials, (Reynolds Metals Co., Richmond, VA 23261, USA). 86/C1556. Weiss, A. D., Boss, C. B., Study of interferences in tandem flame spectroscopy, (Dept. Chem., North Carolina State Univ., Box 8204, Raleigh, NC 27695-8204, USA). 861C1557. Murphy, L. C., Stux, R. L., Lieghty, D. A., Application of Smith - Hieftje background correction to flame AAS, (Allied Analytical Systems, 590 Lincoln St., Waltham, MA 02254, USA).861C1558. Davis, L. A., Krupa, R. J., Winefordner, J. D., Laser excited coherent forward scattering atomic spectrometry, (Dept. Chem., Univ. Florida, Gainesville, FL 32611, USA). 86/C1559. Nygaard, D. D., Schleicher, R. G., Murphy, L. C., Sotera, J. J., Analysis or organic solvents by ICP emission spectrometry, (Allied Analytical Systems, 590 Lincoln St., Waltham, MA 02254, USA). 86/C1560. Lancione, R. L., Evans, S. J., Optimisation of ICP atomic fluorescence spectrometry for the determination of metals in organic solvents, (Baird Corp., Bedford, MA 01730, USA). 86/C1561. Keane, J. M., Fry, R. C., Red and near-infrared photo- diode array atomic emission spectrograph for the simul- taneous determination of C, H, N, 0, F, CI, Br, I and S in gas chromatographic effluent, (Dept.Chem., Willard Hall, Kansas State Univ., Manhattan, KS 66506, USA). 86/C1562. Susil, H. M., Janiszewski, F. W., Maskery, D., Maggs, S. R., A rapid and highly versatile procedure for analysis of metallurgical samples using sodium peroxide fusion and ICP-AES, (INCO Ltd., Central Process Technology, Copper Cliff, Ontario POM 1N0, Canada). 86lC1563. Krupa, R. J., Smith, B. W., Winefordner, J. D., Burner design and applications of laminar, high temperature diffusion flames for atomic spectrometry, (Dept. Chem., Univ. Florida, Gainesville, FL 32611, USA). 86lC 86/C 564. Liddell, P. R., Athanasopoulos, N., Grey, R. G., The effect of background correction speed on the accuracy of AAS measurements, (GBC Scientific Equipment Pty.Ltd., 22 Brooklyn Ave., Dandenong, Victoria 3175, Australia). 565. Graves, G. A., Mincey, D. W., A comparison of Zeeman and Smith - Hieftje background correction systems, (Dept. Chem., Youngstown State Univ., Youngstown, OH 44555, USA). 86/C1566. Pearce, M. J., Edwards, A. G., Boss, C. B., Measurement of rise velocities in premix laminar flames by electrostatic aerosol modulation, (Dept. Chem., Indiana Univ., Bloomington, IN 47405, USA). 86/C1567. Barnett, W. B., Tomasiewicz, S. P., Hager, D. G., User interface design for atomic absorption instruments, (Per- kin-Elmer Corp., 901 Ethan Allen Highway, Ridgefield, CT 06877, USA). 86/C1568. O’Haver, T. C., Kindervater, J., Calibration in conti- nuum-source AA by curve-fitting the transmission profile, (Dept.Chem., Univ. Maryland, College Park, MD 20742, USA). 86/C1569. Halicz, L., Brenner, I. B., Slurry injection inductively coupled plasma atomic emission spectrometry (SIICP- AES) for analysis of geological materials-quantitative appraisal of interference effects, (Geochem. Div., Geolog- ical Survey of Israel, 30 Malkhe Israel St., Jerusalem 95501, Israel). 86/C1570. Pacey, G. E., Straka, M. R., Gord, J. R., Dual phase gas diffusion flow injection analysis: hydride generation atomic absorption spectroscopy, (Dept. Chem., Miami Univ., Oxford, OH 45056, USA). 86/C1571. Park, D. A., Parsons, M. L., Evaluation of ICP-AES for the analysis of Ga and GaAs, (Dept. Chem., Arizona State Univ., Tempe, AZ 85287, USA).86/C1572. Shrader, D. E., Moore, J., Hoobin, D., A new approach towards analytical data handling in low-cost AA, (Varian Instrument Group, AARC, 205 W. Touhy Ave., Park Ridge, IL 60068, USA). 86/C1573. Klueppel, R. J., Spencer, J. L., Plankey, F. W., An on-line air plasma spectrometer for process control, (Baird Corp., 125 Middlesex Turnpike, Bedford, MA 01730, USA). 86/C1574. De Menna, G. J., Marasco, J. P., The speciation and structure elucidation of transition metal complexes by liquid chromatography - DC plasma, (Beckman Instru- ments, Inc., 45 Belmont Drive, Somerset, NJ 08873, USA). 86/C1575. Chan, S.-K., Montaser, A., Analytical performance of an annular helium inductively coupled plasma generated in a low gas flow torch, (Dept.Chem., The George Washing- ton Univ., Washington, DC 20052, USA). 86/C1576. Bolton, J. S., Long, G. L., The effect of organic gases on atomic signals in ICP-AFS, (Dept. Chem., Virginia Polytechnic Inst. and State Univ., Blacksburg, VA 24061, USA). 86/C1577. Pruszkowski, E., Yates, D. A., Ediger, R. D., Anderau, C., Optimisation of automated instrumentation for trace metal determination in oil, (Perkin-Elmer Corp., 901 Ethan Allen Highway, Ridgefield, CT 06877, USA). 86/C1578. Buckley, B. T., Boss, C. B., Modification of a Jarrell-Ash FLA-100 graphite furnace for use as a vaporisation source in plasma emission spectroscopy, (Dept. Chem., North Carolina State Univ., Box 8204, Raleigh, NC 27695-8204, USA). 86/C1579. Urasa, I. T., Ferede, F., Onyari, J. M., Determination of arsenic, phosphorus and selenium using ion chromato- graphy - direct current plasma spectrometry, (Chem.Dept., Hampton Univ., Hampton, VA 23668, USA). 86IC1580. Bilhorn, R. B., Denton, M. B., Charge injection device detection in atomic emission analysis, (Dept. Chem., Univ. Arizona, Tucson, AZ 85721, USA). 86/C1581. Angelis, C. T., Automated arsenic analysis using hydride generation and atomic absorption, (US Borax Research Corp., 412 Crescent Way, Anaheim, CA 92801, USA). 86/C1582. Druon, C., Automatic sampling instrumentation in ICP spectroscopy, (Gilson Medical Electronics, SA, 72 rue Gambetta, 95400 Villiers le Bel, France). 86/C1583. Dowds, E. A., Grant, G. C., Determination of trace elements in weathered flyash, (College of William and Mary, Research Campus, 12070 Jefferson Ave., Newport News, VA 23606, USA).JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY.OCTOBER 1986. VOL. 1 159R 861C1584. Hassett, D. J., Hassett, D. F., The analysis of fly ash by atomic absorption spectroscopy using non-optimum instrument conditions, (Univ. North Dakota, Engineering Experiment Station, Box 8103, Grand Forks, ND 58202, USA). 86/C1585. Supp, G. R., Background effects in the determination of acid soluble lead in magnesium aluminium silicate by atomic absorption spectroscopy, (R. T. Vanderbilt Co. Inc., PO Box 5150, Norwalk, CT 06856, USA). 86/C1586. Pathiratne, K. A. S., Lovett, R. J., Isotope differentiation using atomic absorption spectrometry, (Dept. Chem., North Dakota State Univ., Fargo, ND 58105, USA). 86/C1587.Saunders, C. W., Pleban, P. A., Investigation of nickel as a matrix-modifier in the atomic absorption analysis of tin, (Dept. Chem. Sci., Old Dominion Univ., Norfolk, VA 23508, USA). 861C1588. Holcombe, J. A., McNally, J., The dependence of analy- tical peak shapes in GFAA on microscopic character of the deposited sample, (Dept. Chem., Univ. Texas, Austin, TX 78712, USA). 861C1589. Voellkopf, U., Radziuk, B., Computer-assisted optimisa- tion of flame AAS performance characteristics, (Bodenseewerk Perkin-Elmer & Co. GmbH, D-7770 Uberlingen, FRG). 861C1590. Chow, B. C., Miroff, G. C., Determination of trace mercury in blood and erythrocyte by cold vapour atomic absorption spectroscopy (CVAAS), (Consultant, 19309 Poinsetta Court, Gaithersburg, MD 20879, USA).861C1591. Brown, P. G., Workman, J. M., Caruso, J. A., Determina- tion of electron density in a moderate-power argon MIP, (Dept. Chem., Univ. Cincinnati, Cincinnati, OH 45221, USA). 86/C1592. Kidani, Y., Inagaki, K., Hirose, J., Noji, M., Indirect determination of antitumor platinum complex by atomic absorption spectrophotometry, (Fac. Pharmaceutical Sci., Nagoya City Univ., 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467, Japan). 86/C1593. Selby, M., Galante, L. J., Rezaaiyaan, R., Hieftje, G. M., Microwave-induced plasma detectors for chromato- graphy: the surfatron takes on the Beenakker cavity, (Dept. Chem., Indiana Univ., Bloomington, IN 47405- 4001, USA). 861C1594. Joshi, B. M., Letourneau, V. A., Shah, R. S., Comparison between Zeeman effect and double-beam background correction methods for graphite furnace AA determina- tion of EPA priority pollutants, (Lockheed Engineering and Management Services Co.Inc., PO Box 15027, Las Vegas, NV 89114, USA). 86K1595. Luk, K. K., Boss, C. B., Thermal vaporisation from filaments for sample introduction in MIP, (Dept. Chem., North Carolina State Univ., Box 8204, Raleigh, NC 86/C1596. Selby, M., Rezaaiyaan, R., Hieftje, G. M., Spatial emis- sion properties of a surfatron-sustained plasma, (Dept . Chem., Indiana Univ., Bloomington, IN 47405-4001, USA). 861C1597. Perpall, H. J., Uden, P. C., Hagen, D. F., Marhevka, J. S., Elemental analysis of solids by direct sampling microwave induced plasma emission spectrometry, (Dept. Chem., Lederle GRC Towers, Univ. Massachusetts, Amherst, MA 01003, USA).861C1598. Workman, J. M., Brown, P. G., Caruso, J. A., Electron number density determinations in a novel laminar-flow microwave-induced plasma, (Dept. Chem., Univ. Cincin- nati, Cincinnati, OH 45221, USA). 861C1599. Harada, Y., Koga, T., Teragaki, T., Muto, H., Ito, T., Desk top ICP-AES, (Scientific Instruments Div., Oyama Plant SEIKO I&E, 36-1, Takenosita, Oyama-Cho, Sunto- Gun, Shizuoka 410-13, Japan). 27695-8204, USA). 861C1600. Bartelt, J., Hieftje, G. M., A helium direct current capillary arc and microarc atomiser for atomic emission spectroscopy, (Dept. Chem., Indiana Univ., Blooming- ton, IN 47405-4001, USA). 861C1601. Burns, B. A., Boss, C. B., Efficiency in a microwave plasma: where does the power go?, (Dept. Chem., North Carolina State Univ., Box 8204, Raleigh, NC 27695-8204, USA).86/C1602. Bauer, C. F., Speciation of trace carbonate minerals by evolved gas analysis using microwave plasma, (Dept. Chem., Univ. New Hampshire, Durham, NH 03824, USA). 8611603. 861 1604. 86/1605. 861 1 606. 86/ 1607. 8611608. 861 86/ 609. 610. 861161 1 . 861 161 2. 8611623. 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Chem., The George Washington Univ., Washington, DC 20052, USA). LaFrenier, K. E., Rice, G. W., Fassel, V. A., Flow injection analysis with inductively coupled plasma atomic emission spectroscopy: critical comparison of conventional pneumatic, ultrasonic and direct injection nebulisation, Spectrochim.Acta, Part B , 1985, 40, 1495. (Ames Lab.- USDOE and Dept. Chem., Iowa State Univ., Ames, IA 5001 1, USA). Gray, A. L., The ICP as an ion source-rigins, achieve- ments and prospects, Spectrochim. Acta, Part B , 1985,40, 1525. (Dept . Chem . , Univ . Surrey, Guildford, Surrey GU2 5XH, UK). McDonald, D. C., Sullivan, J. V., Tobin, R. C., Reduction of ground state atom concentration in a boosted output discharge lamp, Spectrochim. Acta, Part B , 1985,40,1599. (CSIRO, Div. Chemical Physics, PO Box 160, Clayton, Victoria 3168, Australia). Skogerboe, R. K., Butcher, G. B., Aerosol ionic redistri- bution: the ionisation repression effect revisited, Spectro- chim. Acta, Part B , 1985, 40, 1631. 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Chem., Carleton Univ., Ottawa, Ontario KlS 5B6, Canada).861 861 160R 8611614. 8611 615. 8611616. 8611 617. 8611 618. 8611 61 9. 8611 620. 8611621. 622. 623. 8611624. 8611625. 8611626. JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 Littlejohn, D., Duncan, I. S., Hendry, J. B. M., Marshall, J., Ottaway, J. M., Comparison of uncoated, pyro-coated and totally pyrolytic graphite tubes for the HGA-500 electrothermal atomiser, Spectrochim. Acta, Part B , 1985, 40, 1677. (Dept. Pure and Applied Chem., Univ. Strathclyde, 295 Cathedral St., Glasgow G1 lXL, UK). Barnett, W. B., Bohler, W., Carnrick, G. R., Slavin, W., Signal processing and detection limits for graphite furnace atomic absorption with Zeeman background correction, Spectrochim.Acta, Part B , 1985,40, 1689. (Perkin-Elmer Corp., 901 Ethan Allen Highway, Ridgefield, CT 06877, USA). MacDonald, R. W., O’Brien, M. 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Smith, F., Cousins, B., Bozic, J., Flora, W., The acid dissolution of sulphide mineral samples under pressure in a microwave oven, Anal. Chim. Acta, 1985, 177, 243. (Chem. Dept., Laurentian Univ., Sudbury, Ontario P3E 2C6, Canada). Grognard, M., Piolon, M., Acid pre-treatment - fusion method for determination of thallium in city waste incineration fly ash by Zeeman atomic absorption spec- trometry, At. Spectrosc., 1985, 6 , 142. (Municipal Lab., Stadhuis, 8400 Ostende, Belgium). Alvarado, J., Campos, F., Ottaway, J.M., Determination of trace levels of calcium in steels by carbon furnace atomic absorption and atomic emission spectrometry, Talanta, 1986, 33, 61. (Chem. Dept., Simon Bolivar Univ., Apartado 80659, Caracas 1080, Venezuela). Kallmann, S., Analysis of sweeps. The cuprous sulphide collecting system, Talanta, 1986, 33, 75. (Ledoux & Co., 359 Alfred Ave., Teaneck, NJ 07666, USA). 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Chem., Willard Hall, Kamas State Univ., Manhattan, KS 66506, USA). 8611 627. 8611628. 861 1629. 8611630. 8611631. 8611632. 861 1633. 8611634. 8611635. 861 861 636. 637. 8611638. Luffer, D.R., Salin, E. D., Rapid throughput nebuliser - spray chamber system for inductively coupled plasma atomic emission spectrometry, Anal. Chem., 1986, 58, 654. (Dept. Chem., McGill Univ., 801 Sherbrooke St. West, Montreal, Quebec H3A 2K6, Canada). Craney, C. L., Swartout, K., Smith, F. W., 111, West, C. D., Improvement of trace aluminium determination by electrothermal atomic absorption spectrophotometry using phosphoric acid, Anal. Chem., 1986,58,656. (Dept. Chem., Occidental Coll., Los Angeles, CA 90041, USA). Radojevic, M., Allen, A., Rapsomanikis, S., Harrison, R. M., Propylation technique for the simultaneous determi- nation of tetraalkyllead and ionic alkyllead species by gas chromatography - atomic absorption spectrometry, Anal. Chem., 1986, 58, 658. (Dept.Chem., Univ. Essex, Colchester, Essex C04 3SQ, UK). Halicz, L., Russell, G. M., Simultaneous determination, by hydride generation and inductively coupled plasma atomic emission spectrometry, of arsenic, antimony, selenium and tellurium in silicate rocks containing the noble metals and in sulphide ores, Analyst, 1986, 111, 15. (Geological Survey of Israel, 30 Malkhe Israel St., Jerusalem, Israel). Barron, D. C., Haynes, B. W., Determination of gallium in phosphorus flue dust and other materials by graphite furnace atomic absorption spectrometry, Analyst, 1986, 111,19. (US Dept. Interior, Bureau of Mines, 4900 Lasalle Rd., Avondale, MD 20782, USA). Timperley, M. H., Priscu, J. C., Determination of nitrogen-15 by optical emission spectrometry using an atomic absorption spectrometer, Analyst, 1986, 111, 23.(Taupo Res. Lab., Div. Marine and Freshwater Sci., Dept. Scientific and Industrial Res., PO Box 415, Taupo, New Zealand). Burguera, M., Burguera, J. L., Flow injection - hydride generation system for the determination of arsenic by molecular emission cavity analysis, Analyst, 1986, 111, 171. (Departamento de Quimica, Facultad de Ciencias, Universidad de Los Andes, Apartado Postal 542, Merida 5101-A, Venezuela). Davies, J. A., Jefferies, A. C., Size distribution of particulate matter in exhaust gases in inductively coupled plasma atomic emission spectrometry, Analyst, 1986, 111, 221. (Anal. Chem. Branch, Chem. and Explosives Div., MOD(PE), AWRE, Aldermaston, Berkshire RG7 4PR, UK). Walton, S. J., Sequential determination of arsenic, anti- mony and bismuth in low-alloy steels by hydride genera- tion inductively coupled plasma atomic emission spec- trometry, Analyst, 1986, 111, 225.(Applied Research Laboratories, Wingate Rd. Luton, Bedfordshire LU4 8PU, UK). Gal, I., Halicz, L., Determination of rock-forming ele- ments in the presence of large amounts of uranium and zirconium using inductively coupled plasma atomic emis- sion spectrometry, Analyst, 1986, 111, 227. (Geological Survey of Israel, 30 Malkhe Israel St., Jerusalem 95501, Israel). Branch, C. H., Hutchison, I)., Comparison between isobutyl methyl ketone and diisobutyl ketone for the solvent extraction of gold and its determination in geolog- ical materials using atomic absorption spectrometry, Analyst, 1986, 111, 231.(British Geological Survey, 64 Gray’s Inn Rd., London WClX 8NG, UK). Abdillahi, M. M., Snook, R. D., Determination of bromide using a helium microwave induced plasma with bromine generation and electrothermal vaporisation for sample introduction, Analyst, 1986, 111, 265. (Dept. Chem., Imperial College of Sci. Technol., London SW7 2AY, UK).JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 161R 8611 639, 861 1640. 86/1641. 861 1642. 8611643. 8611644. 861 1645. 861 1646. 8611 647. 861 861 648. 649. 8611 650. Dittrich, K., Mandry, R., Investigations into the improve- ment of the analytical application of the hydride technique in atomic absorption spectrometry by matrix modification and graphite furnace atomisation. Part I. Analytical results, Analyst, 1986, 111,269.(Karl-Marx-Univ., Chem. Section, Analytical Centre, Talstrasse 35, 7010 Leipzig, GDR). Dittrich, K., Mandry, R., Investigations into the improve- ment of the analytical application of the hydride technique in atomic absorption spectrometry by matrix modification and graphite furnace atomisation. Part 11. Matrix interfer- ences in the gaseous phase of hydride atomic absorption spectrometry, Analyst, 1986, 111,277. (Karl-Marx-Univ., Chem. Section, Analytical Centre, Talstrasse 35, 7010 Leipzig, GDR). Parisis, N. E., Heyndrickx, A., Method for improving the sensitivity and reproducibility of hydride-forming ele- ments by atomic absorption spectrometry, Analyst, 1986, 111,281. (Dept. Toxicology, State Univ. Gent, Hospitaal- straat 13, 9000 Ghent, Belgium).Falk, H., Hoffmann, E., Ludke, C., Ottaway, J. M., Littlejohn, D., Studies on the determination of cadmium in blood by furnace atomic non-thermal excitation spec- trometry, Analyst, 1986,111,285. (Central Inst. for Optics and Spectroscopy, Acad. of Sci. GDR, Rudower Chaussee 5 , 1199 Berlin, GDR). Le Houillier, R., De Blois, C., Alkyl cyanide medium for the determination of precious metals by atomic absorption spectrometry, Analyst, 1986, 111, 291. (Ministere de 1’Energie et des Ressources, Centre de Recherches Miner- ales, 2700 Rue Einstein, Sainte-Foy, Qukbec G1P 3W8, Canada). Iwamoto, E., Inoike, Y., Yamamoto, Y., Hayashi, Y., Interferences of antimony(V) in the differentiation of antimony(II1) from antimony(V) by extraction with ammonium tetramethylenedithiocarbamate using graphite furnace atomic absorption spectrometry, Analyst, 1986, 111, 295.(Dept. Chem., Fac. Sci., Hiroshima Univ., Hiroshima 730, Japan). Krull, I. S., Bushee, D. S., Schleicher, R. G., Smith, S. B., Jr., Determination in inorganic and organomercury com- pounds by high-performance liquid chromatography - inductively coupled plasma emission spectrometry with cold vapour generation, Analyst, 1986, 111, 345. (Barnett Inst. Chemical Anal. and Dept. Chem., Northeastern Univ., 360 Huntington Ave., Boston, MA 02115, USA). Puri, B. K., Gupta, A. K., Katyal, M., Satake, M., AA determination of cadmium and lead complexes adsorbed on naphthalene, Znt. Lab., 1985, NovJDec., 60. (Dept. Chem., Indian Inst. Technol., New Delhi, India). Marshall, J., Baxter, D.C., Carroll, J., Cook, S., Corr, S. P., Giri, S. K., Durie, D., Littlejohn, D., Ottaway, J. M., Stephen, S. C., Wright, S., The probe furnace in atomic spectrometry, Anal. Proc., 1985,22,371. (Dept. Pure and Applied Chem., Univ. Strathclyde, Cathedral St., Glas- gow G1 IXL, UK). Littlejohn, D., Stephen, S. C., Ottaway, J. M., Slurry sample introduction procedures for the analysis of food- stuffs by electrothermal atomisation atomic absorption spectroscopy, Anal. Proc., 1985,22,376. (Dept. Pure and Applied Chem., Univ. Strathclyde, Cathedral St., Glas- gow G1 lXL, UK). Hill, S., Ebdon, L., Jones, P., Novel approaches to directly coupled high-performance liquid chromatography - flame atomic absorption spectrometry for trace metal speciation, Anal. Proc., 1986, 23, 6.(Dept. Environmental Sci., Plymouth Polytechnic, Drake Circus, Plymouth PL4 8AA, UK). Johnson, D., Headridge, J. B., McLeod, C. W., Jackson, K. W., Roberts, J. A., Direct determination of chromium in gallium arsenide by electrothermal atomisation atomic absorption spectrometry with Smith - Hieftje background correction, Anal. Proc., 1986, 23, 8. (Dept. Chem., Univ. Sheffield, Sheffield S3 7HF. UK). 861 165 1. 8611652. 8611653 8611 654. 8611655. 861 1656. 861 1 65 7. 8611 658. 8611 659. 8611 660. 8611661. 8611662. 861 1663. 8611664. Clarke, P. A., McLeod, C. W., Mowthorpe, D. J., Lee, D. J., Direct determination of volatile trace elements in nickel-base alloys by electrothermal vaporisation ICP atomic emission spectrometry, Anal. Proc., 1986, 23, 15. (Dept. Chem., Sheffield City Polytechnic, Pond St., Sheffield S1 lWB, UK).McCabe, S., Ottaway, J. M., Novel method for the determination of arsenic, antimony and selenium in single-cell protein (Pruteen), Anal. Proc., 1986, 23, 16. (Dept. Pure and Applied Chem., Univ. Strathclyde, Cathedral St., Glasgow G1 IXL, UK). Hall, D. H., Littlejohn, D., Ottaway, J. M., O’Haver, T. C., Software-controlled system for automatic background correction in inductively coupled plasma optical emission spectrometry, Anal. Proc., 1986, 23, 18. (Dept. of Pure and Applied Chem., Univ. Strathclyde, Cathedral St., Glasgow G1 lXL, UK). Bysouth, S. R., Tyson, J. F., Comparison of curve-fitting algorithms for atomic absorption spectrophotometry, Anal. Proc., 1986, 23, 21. (Dept. Chem., Loughborough Univ. Technol., Loughborough, Leicestershire LEI 1 3TU, UK).Haumann, J., Leipertz, A., Giant-pulsed laser Raman oxygen measurements in a pre-mixed laminar methane - air flame, Appl. Opt., 1985, 24, 4509. (Ruhr-Universitat- Bochum, Institut fur Thermo- und Fluiddynamik, Postfach 102 148, D-4630 Bochum 1, FRG). Kunze, H.-J., Experimental check of local thermodynamic equilibrium in discharges, Appl. Opt., 1986, 25, 13. (Ruhr-Universitat, Institut fur Experimentalphysik V, Postfach 102148, 4630 Bochum 1, FRG). Goldsmith, J. E. M., Laurendeau, N. 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Osberghaus, U., Kurfiirst, U., Stoeppler, M., Determina- tions of lead in whole blood by three versions of atomic absorption spectrometry, Fresenius 2. Anal. Chem., 1985, 322, 739. (Inst. Angew. Phys. Chem., Kernforschungsan- lage (KFA) Julich, D-5170 Julich, FRG). Herber, R. F.M., Roelofsen, A. M., Hazelhoff Roelfzema, W., Peereboom-Stegeman, J. H. J. C., Direct determina- tion of cadmium in placenta. Comparison with a destruc- tive atomic absorption spectrometric method, Fresenius 2. Anal. Chem., 1985, 322, 743. (Coronel Lab. Occup. Environ. Health, Univ. Amsterdam, NL-1105 AZ Amsterdam, The Netherlands). Edwards, W. C., Blackburn, T. A., Selenium determina- tion by Zeeman atomic absorption spectrophotometry, Vet. Hum. Toxicol., 1986, 28, 12. (Coll. Vet. Med., Oklahoma State Univ., Stillwater, OK 74078, USA). Deano, P., Robinson, J. W., Direct determination of manganese in perspiration and urine using atomic absorp- tion spectroscopy, Spectrosc. Lett., 1986, 19, 11. (Chem. Dept., Louisiana State Univ., Baton Rouge, LA 70803, USA).Solinas, M., Angerosa, F., Cichelli, A,, Use of a graphite furnace in the determination of alkaline metals in olive oils by atomic absorption spectrophotometry, Riv. SOC. Ital. Sci. Aliment., 1985, 14,271. (1st. Sper. Elaiotec., Pescara, Italy). Yin, Z., Direct determination of calcium in milk powder by atomic absorption spectroscopy by direct atomisation of a milk suspension, Fenxi Ceshi Tongbao, 1985, 4(5), 22. (Hunan Prov. Inst. Anal. Test., China). 8611 763. 8611764. 8611765. 8611766. 8611767. 861 1768. 8611 769. 8611770. 8611 771. 8611772. 8611773. 861 1774. 8611775. 8611776. VOL. 1 165R Hutchinson, D. J., Disinski, F. J., Nardelli, C. A., Determination of copper in infant formula by graphite furnace atomic absorption spectroscopy with a L’vov platform, J .Assoc. Off. Anal. Chem., 1986, 69, 60. (Ross Lab., Columbus, OH 43216, USA). Grobecker, K. H., Klussendorf, B., Trace heavy metals in marine foodstuffs of various origin. Determination of cadmium, lead and mercury in fresh and dried material by direct solid sampling analysis, Fresenius Z . Anal. Chem., .1985, 322, 673. (Inst. Pflanzenoekol., Univ. Giessen, D-6300 Giessen, FRG). Klussendorf, B., Rosopulo, A., Kreuzer, W., Study of the distribution and rapid determination of lead, cadmium and zinc in livers of slaughtered pigs by Zeeman atomic absorption spectrometry of solid samples, Fresenius Z. Anal. Chem., 1985, 322, 721. (Inst. Tieraerztl. Nahrung- smittelkd., Justus-Liebig-Univ., D-6300 Giessen, FRG). Curtis, P. R., Grusovin, J., Determination of molybde- num in plant tissue by graphite furnace atomic absorption spectrophotometry (GFAAS), Commun.Soil Sci. Plant Anal., 1985, 16, 1279. (State Chem. Lab., Melbourne, Victoria, Australia). Biavati, A., Analysis of glass and feldspathic sands by atomic absorption: study of in-flame chemical interfer- ence, Riv. Stn. Sper. Vetro (Murano, Italy), 1985,15, 179. (Vetreria Parmense Bormioli Rocco S.p.A., Parma, Italy). Suzuki, Y., Serita, F., Simultaneous determination of water-soluble trivalent and hexavalent chromium by anion exchange high-pressure liquid chromatography, Ind. Health, 1985, 23, 207. (Natl. Inst. Ind. Health, Kawasaki 214, Japan). Schroeder, W. H., Jackson, R. A., An instrumental analytical technique for speciation of atmospheric mer- cury, Int. J. Environ.Anal. Chem., 1985, 22, 1. (Atmos. Environ. Serv., Environ. Canada, Downsview, Ontario M3H 5T4, Canada). Nakamura, E., Namiki, H., Determination of mercury in air by atomic absorption spectrometry after collection on manganese dioxide, Bunseki Kagaku, 1986, 35, 27. (Fac. Educ., Yokohama Natl. Univ., Kanagawa 240, Japan). Shibata, Y., Morita, M., Fuwa, K., Determination of ultratrace levels of selenite and selenate in water using high-performance liquid chromatography with automated fluorimetric detection and an on-line reduction system, Analyst, 1985, 110, 1269. (Natl. Inst. Environ. Stud., Ibaraki 305, Japan). Petit, L., Petit, C., Demonstration of a method for tellurium determination in sea water, Rev. Int. Oceanogr. Med., 1985, 79-80, 19. (Univ. Paris, 75251 Paris 05, France).Tominaga, M., Bansho, K., Determination of copper, lead, vanadium and cobalt by graphite furnace atomic absorption spectrometry after a simple and rapid extrac- tion, Kogai Shigen Kenkyusho Iho, 1985,15(2), 97. (Water Pollut. Control Dept., Natl. Res. Inst. Pollut. Resourc., Ibaraki, Japan). Chormann, F. H., Jr., Spencer, M. J., Lyons, W. B., Mayewski, P. A., A solvent extraction technique for determining concentrations of gold and silver in natural waters, Chem. Geol., 1985, 53, 25. (Dept. Earth Sci., Univ. New Hampshire, Durham, NH 03824, USA). Hernandez, C. A., Nguyen, K. L., Sneddon, J., Investiga- tion of transport efficiency of pneumatic nebulisation for dissolved solids in flame and furnace atomic absorption spectrometry, Spectrosc.Lett., 1985, 18, 815. (Dept. Chem., New Mexico State Univ., Las Cruces, NM Tomasik, Z., Zyrnicki, W., Spectroscopic measurements of plasma temperatures in a radiofrequency discharge, Spectrosc. Lett., 1986,19, 179. (Inst. Inorg. Chern. Metall. Rare Elem., Tech. Univ. Wroclaw, 50-370 Wroclaw, Poland). 88003-0004, USA).166R 8611777. 8611778. 8611779. 8611780. 8611 78 1. 8611782. 8611783. 8611784. 8611785. JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 Nakamura, S., Kobayashi, Y . , Kubota, M., A fast response system for electrothermal atomic absorption spectroscopy, Bunseki Kagaku, 1985, 34, 682. (Natl. Chem. Lab. Ind., Tsukuba 305, Japan). Fujiwara, K., Basic studies on atomic absorption and visible absorption spectrometries, Bunseki Kagaku, 1985, 34, 737.(Fac. Sci., Univ. Tokyo, Tokyo 113, Japan). Tikkanen, M. W., Niemczyk, T. M., Time gating for the elimination of interferences in electrothermal vaporisation inductively coupled plasma atomic emission spectrometry, Anal. Chem., 1986, 58, 366. (Sci. Lab. Div., Health Environ. Dept., Albuquerque, NM 87106, USA). Pacey, G. E., Straka, M. R., Gord, J. R., Dual phase gas diffusion flow injection analysis - hydride generation atomic absorption spectrometry, Anal. Chem., 1986, 58, 502. (Dept. Chem., Miami Univ., Oxford, OH 45056, USA). Fernando, L. A., Heavner, W. D., Gabrielli, C. C., Closed-vessel microwave dissolution and comprehensive analysis of steel by direct current plasma atomic emission spectrometry, Anal. Chem., 1986, 58, 511. (Res. Cent., Allegheny Ludlum Steel Corp., Brackenridge, PA 15014, USA).Farnsworth, P. B., The use of pulse-interrupted radiofre- quency excitation to study energy transport and analyte excitation in the inductively coupled plasma, Appl. Spec- trosc., 1985, 39, 1078. (Dept. Chem., Brigham Young Univ., Provo, UT 84602, USA). Steglich, F., Stahlberg, R., Lufter, M., Pawlik, H., On the accuracy of the flame atomic absorption spectrometric determination of main components. Part 6. Comparison between single-beam and double-beam measurements, Fresenius Z . Anal. Chem., 1985,322,555. (VEB Robotron Elektron. Radeberg, DDR-8142 Radeberg, GDR). Hadeishi, T., McLaughlin, R., Direct ZAAS analysis of solid samples: early development, Fresenius Z. Anal. Chem., 1985, 322, 657. (Lawrence Berkeley Lab., Univ.California, Berkeley, CA 94720, USA). Wu, C., Zhang, Z., Wang, S., Zhang, Q., Variation of emission intensity, buffers and internal standards in ICP-AES direct powder analysis, Guangpuxue Yu Guanmu Fenxi, 1985, 5(5), 36. (Chengdu Cent. Lab., 8611 791. 8611792. 8611793. 8611794. 8611795. 8611796. 861 1797. 3611798. Omenetto, N., Smith, B. W., Hart, L. P., Cavalli, P., Rossi, G., Laser induced double resonance ionic fluores- cence in an inductively coupled plasma, Spectrochirn. Acta, Part B , 1985,40, 1411. (Chem. Div., Jt. Res. Cent., Ispra, Italy). Faires, L. M., Effects of sample matrix on detection limits in analytical inductively coupled plasma Fourier transform spectrometry, Spectrochim. Acta, Part B , 1985, 40, 1473. (Chem. Div., Los Alamos Natl. Lab., Los Alamos, NM 87545, USA).Nakahara, T., Wasa, T., Nondispersive atomic fluores- cence spectrometric determination of lead by hydride generation, Anal. Sci., 1985, 1, 291. (Coll. Eng., Univ. Osaka Prefect., Mozu-Umemachi 591, Japan). Fleckenstein, J., Direct determination of mercury in solid biological samples by Zeernan atomic absorption spec- trometry (ZAAS) with the graphite furnace, Fresenius Z. Anal. Chem., 1985, 322, 704. (Inst. Prod. Oekotoxikol., Bundesforschungsanst. Landwirtsch. Braunschweig-Voel- kenrode, D-3300 Braunschweig, FRG). Jahr, K., Clinical significance and technique of blood-lead determination with Zeeman AAS, Fresenius Z. Anal. Chem., 1985, 322, 736. (Med.-Diagn. Labor, D-5400 Koblenz, FRG). Baxter, D. C., Littlejohn, D. , Ottaway, J. M., Fell, G.S., Halls, D. J., Determination of chromium in urine by probe electrothermal atomisation atomic emission spectrometry using a low-resolution monochromator, J. Anal. At. Spectrom., 1986, 1, 35. (Dept. Pure Appl. Chem., Univ. Strathclyde, Cathedral St., Glasgow G1 lXL, UK). Burguera, J. L., Burguera, M., Alarcon, 0. M., Determi- nation of sodium, potassium, calcium, magnesium, iron, copper and zinc in cerebrospinal fluid by flow injection atomic absorption spectrometry, J . Anal. At. Spectrom., 1986, 1, 79. (Fac. Cienc., Univ. Los Andes, Merida, 5 1 01-A, Venezuela). Jiang, Z., Liao, Z., Li, H., Xie, J., Lu, D., Application of d.c. arc spectrographic method in controlled argon - oxy- gen atmosphere in determination of trace amounts of zinc, cadmium, copper, nickel, chromium and vanadium in human hair, Wuhan Daxue Xuebao, Ziran Kexueban, - - - - I .. -. - - 1 \ I- 1 . 1 . . = Y .JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 167R 861 1804. 8611 805. 8611 806. 8611 807. 8611808. 861 1 809. 8611 8 10. 861181 1. 861 181 2. 8611 8 13. 8611 8 1 4. 8611 8 15. 8611816. Jarvis, I., Jarvis, K. E., Rare earth element geochemistry of standard sediments: a study using inductively coupled plasma spectrometry, Chem. Geol., 1985, 53, 335. (Sch. Geol. Sci., Kingston Polytech., Kingston-upon-Thames, Surrey KTl 2EE, UK). Sugimae, A., Barnes, R. M., Determination of trace elements in suspended particulate matter by inductively coupled plasma atomic emission spectrometry with elec- trothermal vaporisation, Anal.Chem., 1986, 58, 785. (Dept. Chem., Univ. Massachusetts, Amherst, MA 01003- 0035, USA). Marquardt, D., Liideritz, P., Leppin, S., Grosser, J., Multi-element analysis of urban aerosol by ICP-spec- trometry. Z. Chem., 1985, 25(11), 408. (Bereich Med., Humboldt-Univ. Berlin, DDR-1040 Berlin, GDR). Donard, 0. F. X., Rapsomanikis, S., Weber, J. H., Speciation of inorganic tin and alkyltin compounds by atomic absorption spectrometry using an electrothermal quartz furnace after hydride generation, Anal. Chem., 1986, 58, 772. (Chem. Dept., Univ. New Hampshire, Durham, NH 03824, USA). Revoil, G., Method for pre-concentration of trace ele- ments in water. Application to inductively coupled plasma multi-elemental analysis, Doc. B. R. G.M., 1985, 91, 162 pp. (France).Tikkanen, M. W., Arellano, S. D., Goulter, J. E., Routh, M. W., Trace element analysis in wastewater using a new ICP-AES sample introduction - excitation system, Spec- troscopy (Springfield, Oreg.), 1986, 1, 30. (Applied Research Labs., 9545 Wentworth St.. Sunland, CA 91040, USA). Quast, D., Viohl, J., Quantitative atomic absorption spectrometric determination of cadmium (Cd) extractable from denture plastics under simulated intraoral conditions, Dtsch. Zahnaerztl. Z . , 1985,40, 1187. (Abt. Werkstoffd., FU Berlin, 1000 Berlin, FRG). Omenetto, N., Winefordner, J. D., Scattering in atomic fluorescence flame spectroscopy, Prog. Anal. At. Spec- trosc., 1985, 8, 371. (Chem. Div., Jt. Res. Cent., Ispra, Italy). Langmyhr, F. J., The solid sampling technique of atomic absorption spectrophotometry-what can the method do?, Fresenius Z.Anal. Chem., 1985, 322, 654. (Dept. Chem., Univ. Oslo, N-0315 Blindern, Norway). Krull, 1. S., Recent advances in new and potentially novel detectors in high-performance liquid chromatography and flow injection analysis, ACS Symp. Ser., 1986, 297(Chro- matogr. Sep. Chem.), 137. (Barnett Inst., Northeastern Univ.. Boston, MA 02115, USA). Cresser, M. S., Ebdon, L. C., McLeod, C. W., Burridge, J. C., Atomic spectrometry update-environmental analy- sis, J. Anal. At. Spectrom., 1986, 1, 1R. (Dept. Soil Sci., Aberdeen Univ., Meston Walk, Old Aberdeen AB9 2UE, UK). Frech, W., Lundberg, E., Cedergren, A., Investigations of some methods used to reduce interference effects in graphite furnace atomic absorption spectrometry, Prog.Anal. At. Spectrosc., 1985, 8, 257. (Dept. Anal. Chem., Univ. Umei, S-901 87 Umei, Sweden). Fernando, L. A,, Kovacic, N., Axial distribution of analyte emission in inductively coupled argon plasma, Fresenius Z . Anal. Chem., 1985, 322, 547. (SpectraMetrics, Inc., Andover, MA 01810, USA). 86t 1817. 8611 81 8. 8611 8 1 9. 8611820. 8611821. 861 861 861 861 822. 823. 824. 825. 8611826. 8611 827. 8611828. 8611829. 8611 830. Bekyarov, G., Futekov, L., Andreev, G . , Lowering of the detection limit in atomic absorption spectroscopy using ensemble summation of signals obtained by means of a microsample technique. Fresenius Z. Anal. Chern., 1985, 322, 563. (Cent. Lab., Plovdiv Univ., BG-4000 Plovdiv, Bulgaria). Dungs, K. W., Hopp, D., Neidhart, B., Modifications and new developments for HGA graphics software for Perkin- Elmer Model 3600 data station with Zeeman15000-spec- trometer, At.Spectrosc., 1985, 6(6), 161. (Inst. Arbeitsphysiol., Univ. Dortmund, 4600 Dortmund 1, FRG). Scheeline, A., Implications of line number to line intensity logarithmic relationship for emission spectrochemical analysis, Anal. Chern., 1986, 58, 802. (Sch. Chem. Sci., Univ. Illinois, Urbana, IL 61801, USA). Kindervater, J., O’Haver, T. C., Calibration in conti- nuum-source atomic absorption by curve fitting the transmission profile, J. Anal. At. Spectrom., 1986, 1, 89. (Dept. Chem., Univ. Maryland, College Park, MD 20742, USA). Marcus, R. K., Harrison, W. W., Hollow cathode plume as an atomic emission source for elemental analysis of metal alloys, Anal. Chem., 1986, 58, 797. (Dept. Chem., Univ. Virginia, Charlottesville, VA 22901, USA). Kamla, G . 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Xue, J., Cuo, Z., Zhang, G., Atomic absorption spectro- scopic determination of silver in palladium - silver - sili- con - iron amorphous alloys with thiourea as the complex- ing agent, Guangpuxue Yu Guungpu Fenxi, 1985,5(5), 64. (Inst. Phys., Acad. Sin., Beijing, China). Nazarenko, I. I., Kislova, I. V., Kashina, L. I., Malofeeva, G. I., Petrukhin, 0. M., Murinov, Yu. I . , Zolotov, Yu. A., Atomic absorption determination of heavy metals in water and other environmental samples after sorption pre-con- centration on a polymeric thioether, Zh. Anal. Khim., 1985, 40, 2129. (Inst. Mineral. Geochem. Cryst. Chem. Rare Elements, Moscow, USSR). Chang, S. B., Chakrabarti, C. L., Huston, T. J., Byrne, J. P., Estimation of partial pressure of oxygen inside the graphite furnace used for atomic absorption spectrometry, Fresenius Z. Anal. Chem., 1985, 322,567. (Dept. Chem., Carleton Univ., Ottawa, Ontario K1S 5B6, Canada). 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ISSN:0267-9477    

DOI:10.1039/JA986010155R

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 313 Editoria I Progress of JAAS-Two Extra Issues in 1987 Now that the new journal is firmly launched, and the process of transferring the annual reviews from Annual Reports on Analytical Atomic Spectroscopy (ARAAS) to the new bimonthly format in Atomic Spectrometry Updates is essen- tially complete, it is perhaps time to take stock, and to report on our view of the progress of JAAS. The Editorial Board met recently at the 3rd BNASS Meeting in Bristol, and was able to review the current status of the Journal in the presence of several other members of the Advisory Board from both Europe and the USA. All the indicators we have had so far suggest that the community of analytical atomic spectroscopists has warmly welcomed the new journal, and its concept of providing within one cover news information, original research papers and up to date reviews.The aim of offering a journal of particular value to the user of atomic spectrometric instru- ments also appears to be widely appre- ciated, not only by the users themselves, but also by those looking for a more suitable medium to promote new methods and concepts of practical importance. Whenever a new primary journal is launched there are always two key ques- tions to be answered. Will scientific col- leagues submit high quality papers to the journal in sufficient numbers, and will the journal sell? In the case of JAAS, we also accepted the challenges of transferring ARAAS into a bimonthly format, and of obtaining sufficient interesting informa- tion for our news pages.The reader may, of course, make his or her own judge- ment, but the Board are delighted with the response to all these previously un- known factors. The number and quality of primary papers being submitted is rather greater than our expectations. This issue is a particularly large one, but we believe all six issues in 1986 will contain articles of major interest to many subscribers, and at a level which will make them particularly useful in many laboratories. The spread of topics has broadened to include ICP-MS, spark-source MS and XRF, as well as the more common ETA, flame, AAS and ICP papers. We are pleased with the response received through our US Asso- ciate Editor, Jim Harnly, and understand that our North American colleagues find his involvement convenient and worth- while.In addition, papers have been received from many parts of the world and indicate a general enthusiasm for JAAS. The transition of ARAAS into Atomic Spectrometry Updates has gone more smoothly than anyone involved could have imagined. The Board would like to take this opportunity to thank all contri- butors for their continued efforts, and particularly to authors for keeping to their deadlines. In 1987, ASU reviews will include X-ray fluorescence papers, and abstracting will incorporate papers in this field. Several correspondents have com- mented on the lack of a reference list at the end of each review. Of course, detailed information about each paper is given in the ASU References Sections, but of necessity the appropriate refer- ences will only be found in earlier issues of the journal.This problem was particularly acute in the first few reviews, in which the majority of references were to a listing published in a special supplement. This decision, to exclude publication of a reference list with each review, was origi- nally made to avoid duplication and increased costs, but to help readers the Board have now decided to include a brief listing of references to published articles only (those without a prefix C) at the end of each review. This will start with the first review in 1987, and will provide a rapid indication of the source of the material. More detailed information, if required, can then be obtained from the appro- priate full reference lists, We hope these changes will make our reviews more immediately useful, and reinforce the favourable comments received following the transfer of ARAAS to JAAS.The most exciting development of the journal that we are announcing through this Editorial is that there will be eight issues of JAAS in 1987. The six regular issues will be published in the same months as in 1986, but two Special Issues will be published as an integra! part of the 1987 subscription package. Papers from two conferences, the 3rd BNASS held recently in Bristol, and the 1987 Winter Conference on Plasma and Laser Spectro- chemistry to be held in Lyon in January 1987, will be published in separate issues, hopefully in March and September, 1987, respectively. Although a policy of pub- lishing conference papers is not exclusive to JAAS, we believe it is a useful means of encouraging authors to bring their work to full publication at an early stage.We also anticipate that subscribers will find these issues a valuable addition to their journal. The price of the journal in 1986 was set on the basis of the expected sales figures derived from our original market survey, and the need for a steady strengthening of the financial base over a three-year period. We are delighted to report that our end-1986 subscription target figure was passed exactly half way through the year, and subscriptions have continued to come in at a steady rate. As a result of this favourable response to the journal, the Royal Society of Chemistry is able to adopt a more attractive pricing policy than expected for 1987. It is anticipated that the two extra issues will be larger than average and will add at least 3&40'/0 to the volume of the journal. Despite the increased costs associated with these Special Issues, the RSC has agreed to raise the subscription price by only 9%, in line with the price rises being applied to all other RSC journals in 1987. The Board will continue to look for ways of improving our product and will always welcome comments. We would particularly welcome news and informa- tion from all round the world for incor- poration in our news pages. We have been greatly encouraged by the very favourable response to all aspects of JAAS from all parts of the world. We hope the changes that have been made recently, and the new developments mentioned above, will make JAAS even more valuable to prac- tising atomic spectroscopists. Professor J. M. Ottaway Chairman, JAAS Editorial Board

ISSN:0267-9477    

DOI:10.1039/JA9860100313

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

314 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 Atomic Spectrometry Viewpoint Les Ebdon Department of Environmental Sciences, Plymouth Polytechnic, Drake Circus, Plymouth PL4 8AA, UK and Robert C. Hutton VG Isotopes Ltd., Ion Path, Road Three, Winsford, Cheshire CW73BX, UK During SAC '86/3rd BNASS in Bristol, UK, Professor John Ottaway (J. M. 0.) interviewed Professor Les Ebdon (L. E.) and Dr. Robert C. Hutton (R. C. H.) about recent developments in their careers and in ICP-MS. L to R; Professor J . M . Ottaway, Dr. R. C. Hutton and Professor L. Ebdon in Bristol J. M. 0. A t this stage of the development of ICP-MS it seems of interest to review the current state of the art in this field and the status of worldwide interest that has now been created in the technique.W e took the opportunity of the SAC '86/BNASS Con- ference to interview the newest Professor of Analytical Chemistry in the UK, Professor Les Ebdon, and also the recently pro- moted Product Manager of VG Isotopes, Dr. Robert Hutton. Turning first of all to you, Professor Ebdon, could you tell us something about your recent career activi- ties and your rapid rise to the level of Professor at Plymouth Polytechnic? L. E. As you know, John, I joined Plymouth Polytechnic about 5 years ago as Reader in Analytical Chemistry. About the same time they introduced a scheme of Polytechnic Professorships and we now have about 10 such Polytechnic Professors. It is a title which is bestowed as a mark of distinction within the Institu- tion and I am grateful to the RSC for the award of the Silver Medal this year, a mark of recognition, which certainly helped in my being awarded a chair.During those 5 years we built up a very active research school in analytical chem- istry at the Polytechnic. We have some 18 research students in a relatively small chemistry group at the moment. I suppose about a dozen of them work for me in one way or another and nearly all of them are working on analytical projects. We have been very successful in obtaining grant money for our work on slurry atomisation into various plasma sources and graphite furnaces and also for our work on coupled chromatography - atomic spectroscopy for the speciation of trace metals in a variety of matrices. One of these matrices is of course foodstuffs, and it is in connec- tion with this that we have had two large grants from MAFF to employ postdoc- toral fellows to work on their ICP-MS system at the Food Science Laboratory in Nonvich.J. M. 0. So you are now technically responsible as a user of ICP-MS instrumentation. Turning to Robert Hut- ton, who has recently been promoted to the post of Product Manager, could you tell us something about the way developments are handled in VG, and how you have risen to your current position as Product Manager? R. C. H. Well John, I spent about 7 years prior to joining VG working at Tioxide in Stockton, where I worked with optical ICP spectrometry and atomic absorption spectrometry. I joined VG Isotopes about 2 years ago as their Applications Manager, and at that time we were in the process of setting up an Applications Laboratory to exploit ICP-MS.Since then, the technique has expanded to such an extent, there now being about 40 VG instruments in the field, that rather than rely on academic resources for the devel- opment, the major developments in the instrumentation are now only being car- ried out by the current instrument manu- facturers. J. M. 0. My impression is that ICP-MS instruments from both of the main manu- facturers are now fairly widely distributed around the world. Could you comment in general where such instruments are going in terms of countries and also in user types? R. C. H. I believe to date there are somewhere between 60 and 80 systems in the field split between both manufactur- ers. The majority of instruments are in North America and Canada, although there are about eight instruments in the UK, maybe about eight instruments in Germany, several other instruments in the Far East, China, mainland China and Japan.The applications for ICP-MS in the world are varied. The majority of applica- tions initially went into geochemistry groups at universities and in service labor- atories, probably primarily because of the background work carried out by Alan Gray and Alan Date which was geo- chemistry based. A great number instru- ments now have been placed into nuclear laboratories, for example the Lawrence Livermore Laboratories and Los Alamos Laboratories in America, where they are doing both nuclear uranium analysis and environmental analysis, environmental monitoring. J. M. 0. Obviously the price of instrumentation restricts the number of areas that can really afford to adopt this technique. Some of the laboratories you mentioned are well financed in equipment terms, but do you have many more ordi- nary users looking f o r the routine analysis of samples? R.C. H. Even at this stage in the devel- opment of the instrumentation, there are some service laboratories, independent service laboratories in Germany and in the US and Canada, who have purchased the instruments both from ourselves and from SCIEX. So at this stage there are groups in the States, for example, who are actually earning a living from the tech- nique. J. M. 0. Les, you are associated through your postdoctoral colleagues, with what I believe was the first instrument to be delivered in the UK at the MAFF Labora- tories that you mentioned earlier.Could you say a little bit about the experience at MAFF with this particular instrument system? L. E. ICP-MS offers very exciting possi- bilities in food analysis. There is very considerable interest in extremely low levels of metals in the diet, that is now being extended to looking at speciation and the fate of these elements in the digestive system. The capability of iso- topic measurement offers possibilities of stable isotope work, which of course, is much more attractive than using radio- labelled isotopes. The instrument which was delivered to Norwich, I think I would be correct in saying, was the first comrner- cia1 instrument delivered to a user in the world. Not surprisingly, there were one or two teething problems.In the past, users of mass spectrometers have accepted315 IOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 1987 WINTER CONFERENCE ON PLASMA AND LASER SPECTROCHEMISTRY LYON, January 12-16,1987 FEATURES The 1987 Winter Conference on Plasma and Laser Spectrochemistry will feature recent developments in this field. The Conference topics will include the various types of plasmas (ICP, DCP, MIP and GDL) and hyphenated methods such as ICP-MS, chromatography, flow injection and Fourier transform spectroscopy. A symposium will be devoted to different aspects of laser spectrochemistry (laser induced atomic fluorescence, intracavity laser absorption and laser enhanced ionisation spectrometry). The Conference will cover fundamental aspects, technological developments and applications, along with manufacturer seminars.The Conference will be held in Lyon, January 12th to January 16th, 1987 at the Mapotel Best Western Hotel. The official language of the Conference will be English. SCIENTIFIC PROGRAMME A large number of plenary lectures will allow the presentation of the state of the art in plasma and laser spectrochemistry. Although some oral presentations will be accepted, poster presentations are highly recommended in order to facilitate exchange of information and to overcome language problems. Original papers will be published following the meeting after peer review in the Journal of Analytical Atomic Spectrometry. Information stands will be available for plasma and laser instrumentation companies.INVITED SPEAKERS The following scientists have been invited to present plenary lectures on plasma and laser spectrochemistry: T. Berthoud (Fontenay, France), M. Blades (Vancouver, Canada), P. W. J. M. Boumans (Eindhoven, The Netherlands), J. Broekaert (Dortmund, FRG), R. F. Browner (Atlanta, USA), L. Faires (Los Alamos, USA), H. Falk (Berlin, GDR), K. Govindaraju (Nancy, France), G. M. Hieftje (Bloomington, USA), G. Horlick (Edmonton, Canada), G. Knapp (Graz, Austria), C. W. McLeod (Sheffield, UK) and G. C. Turk (Gaithersburgh, USA). REGISTRATION Further details and Conference and Hotel registration forms may be obtained from: J. M. Mermet, Winter Conference, Laboratoire des Sciences Analytiques, Bat. 308, Universite Claude Bernard - Lyon I, 69622 Villeurbanne Cedex, France.316 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 fairly lengthy down-time periods and have been used to putting in a very great deal of maintenance. I think it was always clear to the manufacturers of ICP-MS that the trace metal market, being used to optical emission and atomic absorption spec- trometers, would not accept that kind of level of maintenance and of down-time. Many of the early modifications which went into the instrument were really to the effect of reducing the amount of time the instrument might be down and to improving its reproducibility and reliabil- ity. Looking back on it now, we were remarkably successful in doing some things ourselves and also feeding back information to VG that I am sure helped them to make relatively minor modifica- tions to the instrument, which now means that it has a very high percentage of useful time.Talking with other users this week, I have got an impression that we are, perhaps, doing better than most with the experience that we have. R. C. H. Perhaps to elaborate on the point made by Les, it is clear that mass spectroscopists traditionally have had much more hardware experience than that which is normally prevalent in normal analytical laboratories. It has probably been a major challenge to make the data which comes out of the instrument much more reliable. Traditionally the quadru- poles which are used in the instrument have been used for a much less exacting purpose than trace analysis, and it requires quite considerable re-engineer- ing of the electronics to get them to the state they are now, where typically, repro- ducibility is of the same sort of order as that experienced in an optical ICP.J. M. 0. When ICP-MS came out claims were made by various speakers that it would present a technique relatively free from spectral interferences. More recent research has suggested that this is not the case, and that there are significant prob- lems from overlap with molecular ions. Current research is aiming to solve some of these problems. Would you both like to comment on the current position as you see it? L. E. Well I must say John, that those claims never fooled me. I am old enough to remember when flame AA had no interferences and then electrothermal atomisation came along and it had no interferences.By the time inductively coupled plasmas came along, and it was said that they had no interferences, one of the first things we did was to look for interferences. So I was not surprised to find that there were some unexpected problems with ICP-MS. Of course a lot of them have been exaggerated at this stage of the technique, because people like ourselves have made an extensive study to see what interferences might be there, and have set-up one or two, what you might call, worse case possibilities. We have now been through the typical learn- ing curve where we know how to prepare samples to minimise these spectral inter- ferences. Its a very similar pattern to the one that you will remember from the use of electrothermal atomisation, in which you made such a major contribution yourself.Clearly chloride media are less suitable for ICP-MS than, for example, having a nitrate matrix, and this means by careful attention to digestion procedures we can greatly reduce some of the prob- lems. In our work on foods the major problems have appeared around vana- dium and arsenic and these can certainly be alleviated by reducing the amount of chloride present in the matrix and also there are possibilities of correction using the alternative chlorine isotope. The other thing we are learning is that, most of these interference problems do not arise within the plasma, but they arise within the interface, and there have already been major advances in interface design. Indeed some of the papers which are appearing now, may already be out of date, in that, users may in fact be using improved interfaces where there are less condensation problems.Maybe that is something Robert may like to comment on. R. C. H. There are certainly quite signifi- cant improvements in the molecular levels, it is true, as you say Les, that any molecules which are formed from acids, for example, are certainly formed from condensation reactions within the inter- face, and it has been a prominent part of the work at VG to control the sampler geometry, in order to minimise these interferences. However, to get things into perspective, there are a great many ele- ments which do not suffer from spectral interferences at all. Certainly above mass 80 you would be hard pushed to find any molecular species apart from the occa- sional low oxide.J. M. 0. Would you say that there is a particular area of application that is going to find greater difficulty with regard to spectral interferences than any other, for example, clinical analysis of trace ele- ments? R. C. H. Certainly the worse case for ICP-MS is the tansition metal region. The work which Les is doing with foods, clearly shows that you can produce good results in this region if you take care of your sample decomposition techniques. J. M. 0. The sensitivity of ICP-MS would suggest that we could hope for the straight- forward determinations of chromium, vanadium and other trace elements in serum and urine. Is this a potential reality? R. C. H. I think it is certainly possible to do these elements very quickly by ICP- MS.Some recent work which we have been doing, in collaboration with Glas- gow Royal Infirmary, has also pin- pointed another strength of the tech- nique, and that is the ability to perform a full elemental survey on intravenous fluids, for total parenteral nutrition. Cer- tainly in the work which we carried out, we saw quite clearly some elements that just had never been quantified before. This has fairly significant advantages over other techniques where one would typic- ally have to want to determine the element rather than have an elemental survey, then decide which element was then a problem. Certainly in the work which we carried out, we observed p.p.b. levels of barium and chromium in the samples, the barium certainly had never been quantified or even suspected in these samples before. J.M. 0. This is obviously a good illustru- tion of the multi-element capability of the technique in discovering unknown prob- lems in a particular sample. Les perhaps you could comment on the future viability of the technique. Do you see it displacing any other techniques, or will it just add to the range of techniques we have available for elemental analysis? L. E. Again John, I do not wish to sound cynical, but, I have heard the stories of one technique replacing another too often before, ICP-AES was supposed to replace flame atomic absorption. I cannot remember who it was that said electro- thermal atomisation would replace flame atomic absorption. Clearly these tech- niques linger on extremely usefully in different peoples’ laboratories.No, I think, it would be largely seen as an additional, but very powerful, tool in the armoury of techniques. I think one of the things is, it will always be a relatively complex technique to use, and we may find that many smaller laboratories will continue to use the established techniques for more routine work. J. M. 0. Do you see any definite or specific areas of analysis to which ICP-MS will bring a great benefit? L. E. Well, obviously anything where the isotopic information is important, for example, in the nuclear industry, a num- ber of environmental and life sciences applications where we can use stable isotopes. It offers a capability that is not offered by any of the traditional optical spectroscopic techniques. The other big advantage of ICP-MS is with higher atomic number elements, for example, lead and uranium.Many of us have struggled for years to do lead by alterna- tive techniques and are just amazed at the capability of ICP-MS; and there is still a great demand for this element at the trace level and so there are a group of samplesJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986. VOL. 1 317 where the atomic mass advantage of ICP-MS will be exploited by users. J. M. 0. Robert, your company also manufactures a GDL-MS system. Could you comment briefly on how you would compare the advantages of the systems relative to each other? R. C. H. Certainly, the strength of ICP- MS initially, would appear to be for solution analysis. Although, certainly the ability to use a laser to ablate solid materials into the plasma expands its capabilities. The GD-MS instrument, (glow discharge mass spectrometer), is primarily aimed at the solids market.Its strength is really that it can analyse high purity metals with little or no sample preparation. However, the source itself is much more complex than the ICP-MS, and requires a double focusing mass spectrometer. It is probably an instru- ment aimed more at the mass spec- trometer user than the routine elemental analysis lab. J. M. 0. Finally, I would like to ask you both to comment on what you see as the current major problems of the technique, and which perhaps represent the greatest challenge for both the researcher and the manufacturer in this field? L. E. Well, obviously one of the major problems for any potential user, is still the cost of the technique and the running costs can be relatively high as well.We would certainly look forward to some advances in cone technology which would mean the sampling cone would have a longer lifetime. Many of the actual prac- tical problems that you encounter in the use of ICP-MS are not necessarily asso- ciated with the instrument, but are those which any user would have if he used any analytical technique at the kind of ultra trace levels that ICP-MS operates at, such as problems of clean room facilities, reagent purity, prevention of losses, memory effects that you would not see with any other technique, these are the kind of practical problems that we are overcoming. Which leads me on to, per- haps, an interesting point I would like to make about future developments.It seems to me the manufacturers have done a fair number of things in improving instrumentation. What I am sure will happen from wider use is a greater emphasis upon the practice and labora- tory technique which will lead us to attempt to solve some of the perceived problems of ICP-MS by laboratory based solutions. Let me give some illustrations. There is concern about how the technique will perform in trace element analysis for large numbers of samples each containing high concentrations of major elements. In practice most ICP-MS users will choose to handle that in their laboratory by using flow injection or some other discrete sample introduction possibility. This immediately takes the pressure off the manufacturer doing things to de-sensitise the multiplier tubes. The other area that I think many users will be interested in, is whether the plasma which is optimal for optical emission spectroscopy, is also optimal for mass spectrometry. It seems to me very unlikely that a torch, which has primarily been designed to obtain the maximum number of excited atoms and ions, is the most appropriate torch to provide a steady stream of ground state ions fired at a small hole in an expensive cone. R. C. H. The low detection limits which are obtainable by ICP-MS, typically down to almost the pg ml-1 range, certainly do present a problem in laboratory practice and it is becoming clear that solution chemistry at this pg ml-1 range is going to be important. One other area of develop- ment however will be in extension of the dynamic range. Certainly this is limited to an upper limit of ca. 10 pg ml-1, but I suspect that future improvement could extend this by at least an order of magni- tude, hence extending the versatility of the technique. J. M. 0. Thankyou both for your contri- butions. It will be interesting to see how the technique develops over the next few years, and hopefully some of the interesting new information and developments will find their way into the pages of JAAS.

ISSN:0267-9477    

DOI:10.1039/JA9860100314

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986. VOL. 1 317 Conference Reports 10th Czechoslovak AAS Seminar: June 7th-12th 1986, Lipno Lake, South Bohemia Perhaps it can be attributed to the such diverse industries in which AAS can be utilised that it has become such a wides- pread analytical technique in Czechoslo- vakia. Analyses using AAS are perfor- med in heavy and light industries as well as in glass manufacture, ore mining, ceramics, chemical and pharmaceutical production, crude oil refineries, food- stuffs, health care and environmental monitoring. All these facets were reflec- ted by the 10th AAS Seminar, organised by the Czechoslovak Spectroscopic Society in June 1986 at Lipno Lake in South Bohemia. Amongst the 150 partici- pants (one third of whom gave an oral or poster presentation) were guests from GDR, Sweden, the UK and Bulgaria. The majority of the contributions were devoted to ETA-AAS problems, con- cerning: the Czechoslovak produced tungsten atomiser WETA, temperature distribution within the atomiser, Cu and Cd atomisation mechanisms in the presence of chelating agents and organic solvents, Zr and Hf atomisation and the WETA tungsten platform; applications of platform techniques in ETA-AAS and the use of the so called miniplatform effect in the analysis of samples with an organic matrix; matrix modifiers in ETA; the determination of trace elements in biolog- ical samples, determination of As in pure chemicals, determination of Ni(C0)4 in air and cigarette smoke, determination of Cu, Cd and Pb in snow, determination of Pb in human hair of people testing fire arms; and background correction with the Zeeman effect.A number of papers dealt with ICP- AES. Apart from lectures summarising the current state of the art of the method and instrumentation, practical applica- tions on the matrix effects of HN03, HC1 and H2S04 on Ni, Fe, Co, Cr, Cu and V determinations, analysis of mineral water, analysis of ferroalloys and a com- parison of the statistical distribution of data from AAS and ICP were also repor- ted. Attention was being paid to the treat- tations at this meeting covered calibration and blank measurements, statistical eval- uation of small sets of data and data validity testing. An additional paper dis- cussed the use of the theory of graphs in analytical chemistry, depicting the possi- bilities of objective evaluation of analy- tical techniques using value analysis.A report on the Czechoslovak pro- duced Trace Mercury Analyser TMA 254 was another welcome presentation. This device is intended to carry out fully Neil Barnett and Vaclav Sychra attempting .some Parlv morning fishing at L i m o Lake ment of data in trace analysis and presen- _ _ - - , " J " 2318 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 automatic mercury determinations in solid, liquid or even gaseous samples without any special sample pre-treat- ment. It is apparent from practical results that the sensitivity of the determination, according to the particular matrix and expressed as characteristic mass, is 0.2- 0.4 ng of mercury.The second generation TMA 254 is equipped with an improved amalgamator and software module. Another interesting paper was on sor- bent extractors, analytically active agents absorbed on various column packings, such as cellulose, glass, alumina and organic sorbents. A paper on the indirect determination of organic substances was also of note. The scientific programme was enhan- ced by the following foreign contribu- tions: N. W. Barnett, Sample Introduc- tion into the MIP; K. Dittrich, Trace Analysis of Metals and Nonmetals by Non-thermal Excitation Spectrometry using Carbon Tube Atomisers; W . Frech, et al., Graphite Furnace AAS Research Directions at the University of Umea; K. Niebergall et al., Trace Analysis of Rare Earth Elements by ICP-AES and ETA- AAS; and A.Petrakiev et al., Hybrid Atomiser and its Application in AAS. The evening discussion on ICP-AES problems can be described as spon- taneous. The event was attended by experienced AAS specialists who are broadening the activities of their labora- tories with this analytical technique for a variety of reasons. The discussion was led by Professor E. PlSko (Komensky University of Bratislava) and was stimu- lated by brief but lively comments from Neil Barnett. The social side of the Czechoslovak. AAS seminars has developed into a mat- ter of tradition. Two evening dances were organised, one with a camp fire and the barbecueing of sausages (perhaps as a substitute for the declining interest in flame AAS among participants), two disco parties and last but not least a half day tour of the nearby beautiful surround- ings.Satisfaction and appreciation of all who took part were expressed to the organis- ing committee headed by Mrs D. Koli- hova, Chairman of the AAS Group, and Dr. V. Sychra, Chairman of atomic sec- tion of the Czechoslovak Spectroscopic Society. The 5th AAS Conference will be organ- ised in 1987 at Chlum u Tiebong, again in South Bohemia. In contrast with the previous seminars the programme will contain more theoretical subjects. Several foreign scientists have already applied to present their papers at next year’s meet- ing and we look forward to yet another highly successful event. Milan Fara Czechoslovak Spectroscopic Society SAC ‘86/3rd BNASS: July 20th=26th, 1986, University of Bristol, UK The Biennial National Atomic Spectro- scopy Symposium (BNASS) is organised by the Atomic Spectroscopy Group of the Analytical Division of the RSC and the Spectroscopy Group of the Institute of Physics as a joint meeting.Bristol Univer- sity was the venue for the third meeting in this series, which was, on this occasion, run in conjunction with the Seventh Society for Analytical Chemistry (SAC) conference, which occurs every third year. The SAC meeting began on Monday 21st, July with a three lecture stream format. Plenaries by Professor J. H. Knox (University of Edinburgh) and Professor M. B. Denton (University of Arizona) opened the first two days with enlighten- ing lectures into “Recent Advances in Dr. E . J . Newman (Chairman of 3rd BNASS Organising Committee) at the BNASS opening ceremony High Performance Liquid Chrornato- graphy” (Monday) and “Concepts for Improved Automated Laboratory Pro- ductivity” (Tuesday), respectively.Traditionally the Wednesday of the week-long SAC conference is given over to social events and a break from the intensity of the lecture programme. This year however saw Wednesday as perhaps being the most difficult and hectic day for the organising committees. It contained not only the usual social events, but also four Update Courses, the 3rd BNASS registration, opening ceremony and open- ing lecture, together with the first of the BNASS poster sessions. Credit must be given to the people involved in the organi- sation of this complex mixture of events. Each event ran virtually without problems and with precision.timing which allowed delegates to move from one event to another as they wished.The SAC Update Courses were well attended covering four varied and interesting areas, which were as follows: Recent Advances in Electrothermal Atomisation (Professor J. M. Ottaway, University of Strathclyde); Diode Array Detectors (Professor A. F. Fell, Univer- sity of Bradford); Ion Chromatography (Dr. M. Cooke, Bristol University and Dr. P. Jones, Plymouth Polytechnic); Robotics and Microprocessors for the Analytical Laboratory (Dr. J. Huddles- ton, AERE Harwell and Dr. J. Newbury, Open University). Dr. E. J. Newman (Chairman of the 3rd BNASS Organising Committee) opened the 3rd BNASS part of the conference, and Dr. W. J. Price intro- duced Professor Leo de Galan (Tech- nische Hogeschool Delft, The Nether- lands) who gave an extremely well presen- ted and skilfully prepared opening lec- ture, the Association of British Spectro- scopists’ Lecture.It made those suffering from midweek lethargy after two days of lectures feel that BNASS had really star- ted and was not just a continuation of the SAC programme. Wearing his physicist’s hat, Professor de Galan delivered a lec- ture entitled “A Physicist’s Appraisal of Recent Developments in Atomic Spec- trometry.” The lecture had a sharp edge highlighting weaknesses in almost the Professor L. de Galan defivering the Associa- tion of British Spectroscopists’ LectureJOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 319 Presentation of the prize for the best poster of the Wednesday session to S .T. Sparkes whole spectrum of atomic spectrometric techniques. This caused a great many of the large audience to come alive ready to defend their own particular field of interest. After the opening lecture the whole conference seemed to have shifted into a higher gear which was immediately noticeable in the very well attended pos- ter session that followed. The poster session (aided by some refreshments courtesy of Applied Research Labora- tories and Chelsea Instruments) was a great success with a great deal of lively discussion and in-depth questioning of the 30 authors. There was also the presenta- tion, by Professor de Galan, of a prize (donated by the Organising Committee) to the author of what was judged to be the best poster, which was well spent by the author, S.T. Sparkes, Plymouth Poly- technic, in furthering the course of science in the hall of residence bar. The BNASS and SAC lecture pro- grammes for Thursday and Friday consis- ted of four streams running simul- taneously, two streams for each. Careful control of timing in each stream by the chairmen allowed delegates to change readily from one stream to another, the organisers having wisely allowed five minutes changeover time between each lecture. Delegates were in fact spoilt for choice by the extremely high level of presentations and some felt that they would have liked to hear more of the papers than was possible. Thursday started with the sad news that Professor Boris L’vov would not be present to give his Plenary Lecture. There was a general feeling of disappointment that this outstanding scientist was unable to attend the conference.This was some- what reduced by the announcement that Professor L’vov has been invited to attend a special meeting being arranged by the Atomic Spectroscopy Group of the Analytical Division of the RSC at Strathclyde University in October. The organising committee excelled itself in filling this Plenary Lecture slot at short notice with another scientist of interna- tional reputation, Professor Jean-Michel Mermet (Universite Claude Bernard, Lyon, France). His lecture entitled “Mixed Gas or Air ICPs: Toys or Tools” was very well received and delegates were grateful to Professor Mermet for inter- rupting his family holiday to attend the conference. The lecture was an enlighten- ing insight into the practical and theoret- ical considerations of several unusual types of lCPs which many people had not seen before.Professor Mermet also stayed for the remainder of Thursday and chaired one of the BNASS sessions. The categories for each of the BNASS lecture sessions for Thursday were: Elec- trothermal Atomisation, Non-thermal Excitation and Background Correction, Fourier Transform Atomic Spectroscopy and Emission Spectroscopy. Each session consisted of an invited speaker together with three contributed papers in the morning sessions and four in the after- noon. Of particular note on Thursday morning was the invited paper presented by Dr. Anne Thorne (Imperial College) entitled “Fourier Transform Atomic Spectroscopy,” this paper perhaps high- lighting the great deal of interest amongst the atomic spectroscopy community in this design of spectrometer even if its present cost makes it unavailable to most workers.Dr. Thorne described the very high resolving power of the spectrometer, which, together with its large light throughput and ability to observe all the spectral elements within a selected band- pass simultaneously, are the reasons why it has aroused such a great deal of interest. Two papers presented on Thursday Professor J . M. Merrnet delivering his Plenary Lecture afternoon are perhaps worth particular mention. The first being the invited lec- ture by Dr. Richard Snook (Chelsea Instruments) on “Torch Configurations and Designs for Inductively Coupled Plasma Atomic Emission Spectrometry.” The first part of his lecture was a discus- sion on viewing an ICP discharge axially rather than from the side and some of the advantages and disadvantages involved. Secondly, he described the design for a laminar flow torch, which has created enough interest for at least one manufac- turer to be producing a commercial ver- sion.This design generates less noise than the traditional tangential flow designs and perhaps offers some improvement in lim- Dr. V. Sychra (left) and Dr. K . Dittrich enjoying the Cider and Cheese evening at the end of the Conference its of detection. The second paper was presented by Dr. David Littlejohn (Strathclyde University) on “Furnace Atomic Non-thermal Emission Source.” This fairly recent development in generat- ing a low-pressure argon or helium disc- harge within a conventional graphite fur- nace using the graphite tube as a cathode is creating considerable interest.It allows electrothermal atomisers to be used in a multi-element fashion without loss of sensitivity compared with single-element absorption measurements. This is a goal that many workers have been striving to reach for several years in order to make the most of what is often considered to be a rather slow technique. Friday started with the Plenary Lecture given by Professor G. Tolg (Institut fur Spektrochemie, Dortmund, FRG) on the subject of “Extreme Trace Analysis of the Elements-The State of the Art Today320 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 ICP-MS exponents: L to R, Dr.R. C . Hutton, Dr. Y. Y. Cheung, Dr. A . L. Gray, Dr. A . R. Date, J . G . Williams and G. E. M. Hall Some of the transatlantic delegates: L to R, C. A . Monnig (recipient of the first Gordon F. Kirkbright Bursary), Professor K . W. Jackson, Dr. J . M. Harnly and Dr. C . B. Boss and Tomorrow.” The Friday BNASS sessions were entitled: Nebulisers and Sample Introduction, ICP-MS, X-ray Techniques and Applications of Atomic Spectroscopy. The Nebulisers and Sam- ple Introduction session was particularly well attended with the lecture theatre being full to capacity for all four presenta- tions. Interestingly, the subject of slurry introduction into electrothermal ato- misers and plasmas had been mentioned several times during the conference and during this session three of the four papers were devoted to analysis by a slurry technique.These papers were also subject to much discussion and many questions showing perhaps the rising interest within the analytical community in this technique. The afternoon session on ICP-MS was also very well attended showing the continuing interest in this growing area. When the conference finally closed on Friday afternoon there was a general good natured feeling amongst the delegates which reflected the very high standard of scientific programme and organisation that they had enjoyed. The combined meeting attracted approximately 450 delegates, from at least 42 different coun- tries giving the meeting a truly interna- tional feel. There were also many young scientists and students several of whom gave excellent presentations at their first major conference.Despite all the jokes about the quality and quantity of the food provided at the conference everyone survived and the 3rd Biennial National Atomic Spectroscopy Symposium had been a great success. Philip Norman Plymouth Polytechnic, UK ASU Highlights Atomic spectrometric analysis may be regarded as a mature area of analytical chemistry, but there is no sign of abate- ment in the effort devoted to its further development. Comments in this review addressed to arc and flame spectrometry note the lack of significant developments of general interest, but in electrothermal atomisation and plasma spectrometry important advances continue to be re- ported. The success of the annular plasma geometry of the ICP has caused users of arc sources to seek electrode configura- tions that produce plasmas having a non- current carrying channel where the sam- ple may be introduced.Similar develop- ments have occurred in microwave plas- mas where torch designs to produce annular and recirculatory plasmas have been described. Microwave plasmas are most widely used as detectors for GC, but electron impact induced fluorescence has also been proposed as a means of spectro- scopic excitation. The universal provision of computing facilities on analytical instruments has resulted in the use of increasingly sophisticated data treat- ments. This trend is acknowledged in this year’s review with both the flame and plasma reports including sections devoted to chemometrics. Hydride generation continues to be widely used, but other forms of chemical vapour generation including the use of volatile chlorides, carbonyls and sulphides have also been reported.Research activity on electro- thermal vaporisation remains at a high level with considerable effort being devoted to the achievement of isothermal atomisation. Various devices including platforms, probes, tube in tube and two- step furnaces have been described and there appears to be renewed interest in metal atomisers, and graphite atomisers with metal carbide coatings. Much research effort is currently aimed at the direct analysis of solid samples without dissolution, and the widespread applica- tion of palladium as a matrix modifier is a highlight of the literature covered by this review. The most important advance in plasma spectrometry has been the coupl- ing of the ICP with mass spectrometric detection and there has been a substantial increase in the number of reports on this subject. For the first time, many of these discuss analytical developments, reflect- ing the deployment of instruments in applications laboratories. The subject attracting the greatest research effort, in relation to the ICP, is sample introduction with both electrothermal and direct inser- tion vaporisation devices being popular. Steady progress has been made on eluci- dating the excitation mechanisms in the ICP and it is hoped that efforts to intro- duce a laboratory standard plasma torch will lead to the provision of a universal data base of plasma parameters. Barry L. Sharp Macaulay Institute, Aberdeen, UK

ISSN:0267-9477    

DOI:10.1039/JA9860100317

出版商:RSC    

年代:1986

数据来源: RSC

摘要:

JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 321 Conferences and Meetings Recent Developments in Atomic Absorp- Music Room of the Staff Club, John St., nace Atomic Absorption Spectrometry.” tion University of Strathclyde in Glasgow. The This will be followed by a poster session October 28-29, 1986, Strarhclyde, UK meeting will commence at 15.30 on Tues- then a dinner in honour of Professor A Joint Meeting of the Scottish Region day 28th with the presentation of the L’vov. and the Atomic Spectroscopy Group of delayed SAC 86 Plenary Lecture by A Plenary Lecture will be given on the RSC will be held in Room I of the Professor B. V. L’vov (Leningrad, Wednesday 29th by J. M. Harnly (USDA, McCance Building, Richmond St. and the USSR) entitled “New Advances in Fur- USA) on “Recent Advances in Con-322 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL.1 tinuum Source AAS.” Other speakers will order to facilitate exchange of informa- inchide: J. M. Ottaway, T. C. O’Haver, tion and to overcome language problems. D. Littlejohn and J. Carroll (University of The presentation of high quality posters Strathclyde, UK), “Development of will be encouraged by several awards Multi-function Instrumentation for AAS and AES Based on Wavelength Modula- tion Background Correction”; C. B. BOSS (North Carolina State University, USA), “Atomic Absorption in Tandem Air - Acetylene Flames”; M. S. Cresser (Uni- versity of Aberdeen, UK), “Are we Get- ting the Best Use Out of Pneumatic Nebulisers?”; B. Welz, B. Radziuk and G.Schlemmer (Perkin-Elmer, FRG) , “Investigation of a Mathematical Model based on Atom Redeposition at the Tube Wall and GF-AAS”; R. D. Snook (Chel- sea Instruments, UK) “Multi-Element Analysis by Fourier Transform AAS”; and D. Littlejohn, S. C. Stephen and J. M. Ottaway (University of Strathclyde, UK) “Recent Advances in the Use of Solid Sampling in ETA-AAS for Food Analysis. ” Registration Fees will be 225 RSC members, f10 retired members and f35 non-members (includes tea, coffee and lunch on 29th October); students f10 (including lunch) or f 5 (excluding lunch). Accommodation will be available in the Business School, University of Strathclyde for 28th October at f18 per single room. Tickets for the Symposium Dinner will cost f15. For further information contact Dr.J. M. Warren, Department of Biochemi- stry, Royal Infirmary, Glasgow, G4 OSF, UK. 1987 Winter Conference on Plasma and Laser Spectrochemistry January 12-16, 1987, Lyon, France The 1987 Winter Conference on Plasma and Laser Spectrochemistry will feature recent developments in this field. The conference topics will include the various types of plasmas (ICP, MIP, DCP and GDL) and hyphenated methods such as ICP-MS, chromatography, flow injection and Fourier transform spectroscopy. A symposium will be devoted to different aspects of laser spectrochemistry (laser induced atomic fluorescence, intracavity laser absorption, laser enhanced ionis- ation spectrometry). The Conference will cover fundamental aspects, technological developments and applications, along with manufacturer seminars. Activities (plenary lectures, poster presentation, manufacturer information stands and accommodation) will all take place at the same location, so that a fruitful exchange can occur between recognised experts, users and customers. The official language of the Conference will be English.A large number of ple- nary lectures will allow the presentation of the state of the art in plasma and laser spectrochemistry. Although some oral presentations will be accepted, poster presentations are highly recommended in (compact disc players and other awards). The companies involved in plasma and laser spectrochemistry will have the opportunity to participate in the exhibi- tion and to deliver seminars in the form that they think the most appropriate.They will also have the opportunity to organise customers’ meetings. For further information contact J. M. Mermet, 1987 Winter Conference, Lab- oratoire des Sciences Analytiques, Bat. 308, Universite Claude Bernard-Lyon I, 43 Boulevard du 11 nov. 1918, 69622 Villeurbanne Cedex, France. Pittsburgh Conference and Exposition on Analytical Chemistry and Applied Spec- troscopy March 9-13,1987, Atlantic City, NJ, USA The 1986 conference and exposition was attended by 29 146 people. Papers at the 1987 conference will be presented in the fields of Air Pollution, Atomic Absorption Spectroscopy, Automated Analysis (Laboratory and Plant), Bio- chemical Analysis, Biomedical and Phar- maceutical, Classical Chemical Analysis, Clinical Chemistry, Computer Applica- tions, Countercurrent Chromatography, Electrochemistry, Emission Spectro- scopy, FI Analysis, Fluorescence - Luminescence, Food Analysis, Forensic and Drug Analysis, Gas Chromatography (Applications, Instrumentation, Theory), Gel Permeation Chromatography, General Analysis, Industrial Hygiene, IR Spectroscopy (Applications, Instrumen- tation, Theory), Ion Chromatography, Laboratory Robotics, Liquid Chromato- graphy (Applications, Instrumentation, Theory), Mass Spectrometry, New Instrumentation, New Instrument Con- cepts, NMR Spectroscopy, Particle Size Analysis, Pesticide Analysis, Plasma Emission Spectroscopy (ICP, DCP), Poly- mer Analysis, Powder Characterisation, Process Stream Analysis, Raman Spec- troscopy, Selective Ion Electrodes, Super- critical Fluid Chromatography, Surface Analysis (Auger, ESCA, SIMS), Ther- mal Analysis, Thin-layer Chromato- graphy, Toxicological Analysis, Trace Analysis, UV - Visible Spectropho- tometry, Water Pollution and X-ray Diffraction/Fluorescence Spectroscopy.For further information contact Mrs. Alma Johnson, Program Secretary, 12 Federal Drive, Suite 322, Pittsburgh, PA 15235, USA. RSC Annual Congress April 13-16, 1987, Swansea, UK The Annual Congress of the RSC will be held at University College, Swansea. The Analytical Symposium will be on Ana- lytical Mass Spectrometry (in association with the British Mass Spectrometry Society) and will include papers by J. H. Beynon, A. Dell, D. F. Hunt, J. J. Monaghan, K. L. Rinehart, P. Roepstorff and R. Self. The Theophilus Redwood Lecture will be given by Dr.A. M. Ure. For further information contact Dr. John F. Gibson, The Royal Society of Chemistry, Burlington House, Piccadilly , London W1V OBN. XXV Colloquium Spectroscopicurn Inter- nationale June 21-26, 1987, Toronto, Canada The XXV CSI will be held at the Hilton Harbour Castle, Toronto, Canada. This North American CSI is sponsored by the Spectroscopy Society of Canada, the Society for Applied Spectroscopy (USA) and the National Research Council of Canada. Nobel Laureates Dr. Gerhard Herz- berg and Professor Arthur L. Schawlow will each present a plenary lecture. Invited lectures on current research topics will be given by approximately 35 young spectroscopists who are making major contributions to the field of atomic and molecular spectroscopy, including: N.Armstrong (Univ. of Arizona), G. I. Bekov (Academy of Sciences, USSR), T. Berthoud (Centre d’Etudes Nucleaires, France), M. Blades (Univ. of British Columbia), M. A. Bolshov (Academy of Sciences, USSR), J. A. C. Broekaert (Inst. f. Spektrochemie & Angewandte Spektros- kopie, FRG), D. C. Compton (Standard Oil Company), G. De Loos (Lab. voor Analytische Scheikunde, The Nether- lands), N. J. Dovichi (Univ. of Wyom- ing), R. Garrel (Univ. of Pittsburgh), J. M. Harris (Univ. of Utah), J. A. Holcombe (Univ. of Texas), D. E. Honigs (Univ. of Washington), S. Houk (Iowa State Univ.), B. Huang (Chang- chun Inst. of Applied Chemistry, China), T. Imasaka (Kyushu Univ. of Japan), K. Kitagawa (Nagoya, Japan), L. B. McGown (Okalahoma State Univ.), J . W. McLaren (National Research Coun- cil Canada), R.Miller (Unilever, UK), J. M. Ramsey (Oak Ridge National Lab.), J. P. Reilly (Indiana Univ.), A. Scheeline (Univ. of Illinois), D. C. Schram (Philips Research Labs., The Netherlands), R. Sturgeon (National Research Council Canada), T. Vo-Dinh (Oak Ridge National Lab.), I. M. Warner (Emory Univ.) and E. S. Yeung (Iowa State Univ.). For further information on the pro- gramme contact Dr. J. D. Wineforder, Department of Chemistry, University of Florida, Gainesville, FL 32611, USA. Symposia are planned for after the Colloquium, with four confirmed to date: Inductively Coupled Plasma Mass Spec- trometry; Line Spectra of the Elements; Graphite Furnace Atomic Spectroscopy;JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY. OCTOBER 1986, VOL.1 323 Ramon M. Barnes, Editor Department of Chemistry GRC Towers University of Massachusetts Amherst, MA 01003-0035 Tel. (413) 545-2294 0 b jec t ive The ICP lnforrnation Newsletter is a monthly journal published by the Plasma Research Group at the University of Massachu- settsand is devoted exclusively to the rapid and impartial dissem- ination of news and literature information related to the devel- opment and applications of plasma sources for spectrochemical analysis. Background lCP stands for inductively coupled plasma discharge, which dur- ing the past decade has become the leading spectrochemical excitation source for atomic emission spectroscopy. ICP sources are also applied commercially as an atom and ion cell in atomic fluorescence spectrometry and as an ion source for mass spec- trometry.The popularity of this source and the need to collect in a single literature reference all of the pertinent data on ICP stimulated the publication onhe ICP lnformation NewSlC3ttef in 1975. Other plasma sources, such as microwave induced plas- mas and direct current plasma jets, have also grown in popularity and are included in the scope of the lCP Information Newsletter. scope As the only authoritative monthly journal of its type, the ICP lnformation Newsletter is read in more than 40 countries by scientists actively applying or planning to use the ICP or other types of plasma spectroscopy. For the novice in the field, the ICP lnformation Newsletter provides a concise and systema- tic source of information and background material needed for the selection of instrumentation or the development of new meth- odology. Edltorlal The ICP lnformation Newsletter is edited by Dr.Ramon M. Barnes, Professor of Chemistry, University of Massachusetts at Amherst, with the assistance of a 20-member Board of National Correspondents composed of leading plasma spectroscopists. The Board members from around the world report news, view- points, and developments. Dr. Barnes has been conducting plasma research on ICPand other discharges since 1968. He also serves as chairman of the Winter Conferences on Plasma Spectrochemistry. Regular Features .Original submitted and invited research articles by ICP and plasma experts. Complete bibliography of all major ICP publications from 1961 to the present. Abstracts of all ICP papers presented at major US and interna- tional meetings..First-hand accounts of ICP developments from na- tions around the world. Special reports on microwave and other plasma progress. Calendar and advanced programs of plasma meetings. Publication of plasma-related patents. .Technical translations and reprints of critical foreign- Critical reviews of plasma-related books. language ICP papers. Conference Activities The ICP lnformation Newsletter has sponsored five international meetings on developments in atomic plasma spectrochemical analysis since 1980 in San Juan, Orlando, San Diego, Leysin, Switzerland, and Kailua-Kona, HI. Meeting proceedings have ap- peared as Developments in Atomic Plasma Spectrochemical Analysis (Wiley), Plasma Spectrochemistry and Plasma Spectrochemistry I I (Pergamon Press) as well as in special issues of Spectrochimica Act& Part B.Subscription Information Subscriptions are available for 12 issues on either an annual or volume basis. The first issue of each volume begins in June and the last issue is published in May. For example, Volume 12 runs from June 1986 through May 1987. Back issues beginning with Volume 1, May 1975 are also available. To begin a subscription, complete the attached order form, and submit it with prepayment or purchase in- formation. For additional information please call (41 3) 545-2294 or contact the Editor. Detach and send to: ICP Information Newsletter, Dr. Ramon M. Barnes Department of Chemistry, GRC Towers, University of Massachusetts, Amherst, MA 01 003-0035 Telephone (41 3) 545-2294 Start a subscription for the following issues (complete): [ ] Volume(s) - (June 198-- May 198-) or [ ] 198- (January-December) or [ ] Send invoice. Current subscription rates are $49 (North America), $69 (Europe, South America), or $75 (Africa, Asia, Indian/Pacific Ocean Areas, Middle East, and USSR). Back issues rates available on request.I enclose: [ ] prepayment or [ J purchase order (No. 1324 JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY, OCTOBER 1986, VOL. 1 and Fourier Transform and Raman Spectroscopy. There will be an exhibition of scientific instrumentation, services and publica- tions. For exhibition information contact either Dr. Andrew T. Zander, Perkin- Elmer Corporation (MS905), 761 Main Avenue, Norwalk, CT 06859-0905, USA or Dr.Andrew W. Boorn, Sciex, Incor- porated, 55 Glen Cameron Road, Thorn- hill, Ontario L3T 1P2, Canada. A social programme is being prepared and will include a dinner, receptions and tours; Wednesday June 24th is an excursion day. For any further information, including registration, contact Mr. L. Forget, Conference Services Office, National Research Council Canada, Ottawa, Ontario K1A OR6, Canada. Spectroscopy Across the Spectrum: Analytical Applications of Spectroscopy July 12-15, 1987, Norwich, UK The Conference (incorporating The First International Near Infrared Spectroscopy Conference) will be held at the University of East Anglia, Norwich. The aim of the meeting is to bring together spectrosco- pists from many different disciplines with the propsect of an interchange of ideas and methods.The meeting will be organ- ised in three parts: general, poster and parallel specialist sessions. There will be an equipment exhibition and a social programme. An internationally recognised group of specialists have been invited to present the plenary and keynote lectures which cover the areas of: combined techniques, data analysis and Fourier transform spec- troscopy. Parallel sessions are planned in the following areas: near IR, atomic absorption, mass, NMR, microwave and IR spectroscopy, process control and chemometrics. Poster contributions are invited in any of these areas. For further information contact Dr. C. S. Creaser, School of Chemical Sciences, University of East Anglia, Norwich NR4 7TJ, UK. Euroanalysis VI September 7-1 1, 1987, Paris, France Euroanalysis VI will be held at the Centre International de Conferences in Paris. The plenary, keynote and contributed lectures will cover all aspects of analytical chemistry, but special sessions are planned to discuss: the use and construc- tion of analytical probes; applications of analytical methods for solving environ- mental problems; analysis of solid-state samples; and new methods of teaching analytical subjects (poster session).There will also be an exhibition and a social programme. Further information is available from GAMS, 88 Boulevard Malesherbes, 75008 Paris, France. Second Beijing Conference and Exhibition on Instrumental Analysis Conference, October 20-23, 1987; exhibi- tion October 19-25 1987, Beijing, China The aim of the conference is to promote academic exchanges on instrumental analysis and friendly relationship among scientists of various countries, and to create favourable conditions for further international co-operation. Symposia on Electron Microscopy, Mass Spec- trometry, Spectroscopy, Chromato- graphy, Radio and Microwave Spectro- scopy will be held separately. During the conference a commercial exhibition on Analytical Instruments will be held. Companies from various coun- tries will exhibit their latest products. For further information please contact: Secretariat of the Beijing Conference and Exhibition on Instrumental Analysis, Room 4311, Beijing Exhibition Centre Hotel, Beijing, China. Telephone: 890541, ext. 481 or 415; telex: 20056 BCEIA CN

ISSN:0267-9477    

DOI:10.1039/JA986010321c

出版商:RSC    

年代:1986

数据来源: RSC