摘要:

--.-.I-- --Proceedinas - - - - - -of the Analytical Division ofThe Chemical Society21 521 521 621 6229235235236236236238238239240CONTENTSNew Member of CouncilReports of MeetingsSummaries of Papers'Activation Analysis in Biologicaland Medical Sciences''Analytical Techniques Used inIndustry'AD Distinguished Service AwardSilver MedalCS Autumn MeetingCS Annual Chemical CongressConferences and MeetingsTesting of High Alumina CementChemical Society LibraryPublications ReceivedAnalytical Division DiaryVolume 12 No 8 Pages 21 5-240 August 197PADSDZ 12(8)215-240(1975)ISSN 0306-1 396August, 1975PROCEEDINGSOF THEANALYTICAL DIVISION OF THE CHEMICAL SOCIETYOfficers of the Analytical Divisionof the Chemical SocietyPresidentG.W. C. MilnerHon. SecretaryP. G. W. CobbSecretaryMiss P. E. HutchinsonHon. Treasurer Hon. Assistant SecretariesJ. K. Foreman D. I. Coomber, O.B.E.; D. W. WilsonEditor, ProceedingsP. C. WestonProceedings is published by The Chemical Society.Editorial: The Director of Publications, The Chemical Society, Burlington House, London, W1 V OBN.Telephone 01 -734 9864. Telex 268001.Subscriptions (non-members) : The Chemical Society, Publications Sales Office, Blackhorse Road, Letch-worth, Herts., SG6 IHN.Non-members can only be supplied with Proceedings as part of a combined subscription with The Analystand Analytical Abstracts.@ The Chemical Society 1975Analytical Sciences Monograph No. 2The Chemical Analysis of WaterGeneral Principles and Techniquesby A. L. Wilson(Water Research Centre. Medrnenharn Laboratory)BRIEF CONTENTS:Introduction. lntormation requirements of Sampling and Analysis Programmes. Sampling.The Accuracy and Reporting of Results. Choice and Sources of Analytical Methods.General Precautions in Water-analysis Laboratories. Manual Analytical Techniques.Automatic and On-line Analysis. Data-handling.Pp. viii + 188 f 7.50Clothbound SBN 0 85990 502 0 CS Members' price f 5.75Orders should be sent through your usual bookseller or direct, enclosing remittance, to-The Publications Sales OfficerTHE CHEMICAL SOCIETYBlackhorse Road, Letchworth, Herts., SG6 1 HNCS Members must write direct to the above address enclosing the appropriate remittanc

ISSN:0306-1396    

DOI:10.1039/AD97512FX027

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

August, 19 75 PUBLICATIONS RECEIVED 239Analytical Division Diary, continuedSEPTEMBERTuesday, 23d-“X-rays and Antiquities,” by H. Barker.“Electron Microprobe Analysis,” by R. E. M.Hedges.“Activation Analysis and Archaeometry,” byG. R. Gilmore.“Potential Analysis of Museum Objects byESCA,” by M. Thompson.Conducted tours of the British MuseumResearch Laboratories or selected galleriesof the British Museum.The Lecture Theatre, The British Museum,Bloomsbury, London W.C. 1.Monday to Thursday, 22nd to 25th: ReadingCS Autumn Meeting. Thursday, 25th: Sym-posium organised by the AD, in con-junction with the Education Division, on“Trends in Education in Analytical Chem-istry. ”For details of the meeting, see p. 236Analytical Division DiarySEPTEMBERWednesday, loth, 2.30 p.m.: NorwichJoint Pharmuceutical Analysis Grot@ on“Bio-analytical Techniques Used in Phar-maceutical Analysis.”“Mass Fragmentography,” by I.Midgley.“Radioimmunoassay,” by A. Sabey.“Electrophoresis,” by P. Corron.The University of East Anglia, Norwich.Thursday, 1 lth, 2.15 p.m. : LoughboroughParticle Size Analysis Group on “Photo-extinction and Light Scattering Tech-niques.”“The Photo-sedimentation Technique,” byT. Allen.“Aerosol Sizing and Holography,” by R.Bexon.atographic Analysis of Pharmaceuticals, ”by J. D. Nicholson.“Recent Developments in ElectrophoreticAnalysis,” by P. H. Corran.“Problems with Polymorphism of MedicinalCompounds,” by A. Clements.“Analysis of Drugs in Forensic Science,”by F.Fish.“Quality Control of Plastics Used in Pharma-ceutical Packaging,” by J. E. Pentelow.“Control of Low Level Cross-contaminantsby TLC,” by J . D. Edmond.“Some Assay Methods in the Measurement ofBio-availability of Drugs in Man,” byA. Bye.Lecture Theatre 31, Department of Pharmacy,Heriot-Watt University, 79 Grassmarket,Edinburgh, EH 1 2H J .“Some Aspects of the HIAC Counter,” byD. J. A. Northby.Room S. 173, Polymer/Chemical EngineeringBuilding, University of Technology, Lough-borough, Leics.Tuesday to Friday, 16th to 19th: BathRadiochemical Methods Group : Liquid Scintil-The Assembly Rooms, Bath.lation Counting Symposium.Tuesday and Wednesday, 16th and 17th:EdinburghAnalytical Division on “Developments inPharmaceutical Analysis.”Tuesday, 16th-“Recent Advances in Pharmaceutical Analy-sis-Do we really need them?” by C.A.Johnson.“Quality Assurance Systems in the Pharma-ceutical Industry,” by W. M. Walker.“Enzymatic Assay Methods for Pharma-ceutical Quality Control,” by A. F. Felland D. R. Stevenson.“Autom-ation in the Analysis of Drugs,” byJ. W. Murfin.“The Fluorimetric Analysis of Oestrogens inOral Contraceptive Preparations, ’’ byJ. H. McB. Miller and P. Duguid.Wednesday, 17th-“Recent Applications of HPLC in Pharma-ceutical Analysis,” by J. H. Knox.“A Review of Applications of DerivativeFormation in the Quantitative Gas Chrom-Wednesday, 17th- 2 p.m.: LondonMicrochemical Methods Group: ElementalAnalyser User Forum on “The Determina-tion of Oxygen.”Discussion to be introduced by S. Bance andC. J . Howarth.City of London Polytechnic, School ofNavigation, 100 Minories, Tower Hill,London, EC3N 1JY.Monday and Tuesday, 22nd and 23rd:LondonAtomic Spectroscopy, Microchemical Methodsand Radiochemical Methods Groups on“Analysis in Archaeology, Art and Anti-quities.”Monday, 22nd-“Analysis and Archaeology,” by J. Musty.“Thermoluminescence Dating,” by M. J.“Mossbauer Spectroscopy in Archaeology, ’ I byAitken.N. J. Seeley.[continued inside back coverPrinted by Heffers Printers Ltd Cambridge Englan

ISSN:0306-1396    

DOI:10.1039/AD97512BX029

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

Vol. 12, No. 8 August, 1975 Reports of Meetings Ordinary Meeting An Ordinary Meeting of the Division was held on Monday and Tuesday, July 7th and 8th, 1976, in the Edward Herbert Building, Uni- versity of Technology, Loughborough. The meeting was devoted to short papers on “Research and Development Topics in Analyti- cal Chemistry.” 215216 ACTIVATION ANALYSIS PYOG. Analyt. Div. Chem. SOC.The Chair at the first session was taken by Dr. W. T. Elwell, Vice-president of the Division, and the following papers were presented and discussed : “Automated Polarography,” by S. R. Porter, V. J. Jennings and J. W. Ogleby; “Applications of Electrochemical Studies of Metal Cyanide Complexes,” by D. T. Wright; “Some Applications of Hexacyanoferrate(II1) in Thermometric Titrimetry,” by L.Kershaw and L. S. Bark; “The Determination of Poly- functional Carboxylic Acids and Phenols, Including Vegetable Tannins, by Catalytic Thermometric Titrimetry,” by E. J. Greenhow and A. A. Shafi. The Chair at the second session was taken by Dr. D. Thorburn Burns and the following papers were presented and discussed : “Deter- mination of Some Precious Metals by Gas - Liquid Chromatography,” by S.A. Tarafdar; “Liquid Chromatography and its Applications to Pesticide Analysis,” by C. Self; “Gas Analysis by Quadrupole Mass Spectrometry,” by J. Hind. The Chair at the third session was taken by Dr. D. I. Coomber and the following papers were presented and discussed : “D6termination of Trace Elements in Soaps and Phosphate Materials by Carbon Furnace Atomic-absorp- tion Spectrometry,” by S.I. Pardhan and J . M. Ottaway ; “The Application of a Tunable Dye Laser System in A.F.S.,” by A. Goldwasser and B. L. Sharp; “The Determination of Europium in Solid Diketonate Complexes Using an Exciton Effect,” by R. Maghzian. The Chair at the fourth session was taken by Dr. W. T. Elwell and the following papers were presented and discussed : “Phosphorimetric Analysis Using a Modified Filter Fluorimeter, ” by D. L. Phillips; “The Analytical Potential of Vapour-phase Auger Spectroscopy,” by D. S. Wooliscroft. Midlands Region An Ordinary Meeting of the Region was held a t 6.30 p.m. on Tuesday, July lst, 1975, in the Haworth Building, The University, Birming- ham. The Chair was taken by the Chairman of the Region, Dr. D. Thorburn Burns. A lecture on “Atomic-absorption Spectro- scopy: Carbon Atomisers,” was given by Professor J . W. Robinson.

ISSN:0306-1396    

DOI:10.1039/AD975120215b

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

216 ACTIVATION ANALYSIS P ~ o G . Analyt. Div. Chem. SOC. Activation Analysis in Biological and Medical Sciences The following are summaries of four of the papers presented at a meeting of the Radio- chemical Methods Group held on November 21st, 1974, and reported in the January issue of Proceedings (p. 7). Whole Body In Vivo Activation Analysis R. W. S. Tomlinson Department of Medicine, King's College Hospital, Medical School, London, S.E.5 The aim of this paper is to give a brief account of the contribution made by neutron-activation analysis to the determination of the body content of certain elements.Interest in determining body composition has been actively pursued only in the past 30 years and the first method adopted was chemical analysis, which of course was not only extremely laborious and time consuming but also of purely academic interest. At about the same time as these chemical analyses were being performed (the early 1950s), the introduction of radioisotopes permitted the measurement by isotopic dilution of an exchangeable proportion of certain body elements. The introduction 10 years ago of in vim neutron-activation analysis allowed for the first time a measurement of the total body content of certain elements on live volunteers, and this time the information was of potential practical use in the management of diseased states.Since 1964, a number of groups of workers have used the technique to determine total body sodium, chlorine, calcium, phosphorus and nitrogen.August, 1975 ACTIVATION ANALYSIS 217 Total Body Neutron-activation Analysis (TBNAA) The determination of the whole body content of sodium, chlorine and calcium by TBNAA depends on the detection of the radionuclides 24Na, BC1 and 49Ca induced by thermal (n,y) reactions, and the determination of the whole body content of nitrogen and phosphorus on the detection of the radionuclides 13N and =A1 induced by fast reactions (n, 2n and n,a, respec- tively).The radioactivity produced by the subject is compared with that produced in a man- like model similarly irradiated. Since the feasibility of the technique was first demonstrated in 1964 by Anderson et aZ.l for the determination of sodium and chlorine (and possibly calcium), other groups have applied the basic method to the determination of body elements.These experiments have shown that measurable activity can be produced by an acceptable dose of radiation. All of the techniques currently employed have achieved uniformity of neutron flow throughout the subject and man-like model to varying extents, and involve bilateral irradiations with fast neutrons moderated in the body tissues and surrounding materials to produce the thermal flux.The reactions that are of interest in the technique are shown in Table I, but for ease of consideration it is probably best to deal with the TBNAA of each element in turn. TABLE I NUCLEAR REACTIONS OF INTEREST IN TOTAL BODY NEUTRON-ACTIVATION ANALYSIS Element of interest Sodium Chlorine Calcium Reaction* D : %3Na(n,~)~~Na I : a4Mg(n,p)24Na D : 37Cl(n,y)38C1 I : I : 41K(n.a)38C1 I : 35Cl(n,2n)34mC1 I: 35Cl(n,y)3sCl D : 4*Ca(n,y)49Ca I : 37C1(n,p)37S D : 40Ca(n,a)37Ar D : 44Ca(n,a)41Ar I : 41K(n,p)41Ar Phosphorus D : 31P(n,a)esAl I : ZsSi(n,p)28A1 Nitrogen D : 14N(n,2n)13N I : 31P(n,2n)30P I: 160(p,a)l3N D : 14N(n,y)15N Expected total body content/ g Na, 105 Mg, 35 C1, 105 K, 140 K, 140 C1, 105 C1, 105 Ca, 1050 C1, 105 Ca, 1050 Ca, 1050 K, 140 P, 700 Si, <5 N, 2100 P, 700 0, 45 500 N, 2100 Target nuclide Induced radionuclide relative I L 1 abundance, Ta y-ray energies/MeV per cent - 100 78-7 24-47 93.10 6.88 75.53 75.53 0.18 24.47 96-97 2.06 6.88 100 92.21 99.63 99.76 99-63 100 14.9 h 14.9 h 37-7 min 7.7 min 37.7 min 32.5 rnin 3 x 1 0 5 ~ ~ 8-76 rnin 5.0 rnin 35.1 d 1.82 h 1.82 h 2-31 rnin 2-31 rnin 10.08 rnin 2.56 rnin 10.08 rnin 1.38 2.75 1.38 2-75 1.6 2-15 2.16 1.6 2.15 2-13 Possible flux depression 3.07 3.10 Auger electrons 1-29 1-29 1.79 1.79 0.51 from pf 0.51 from #If 0.51 from /3+ 10.8 *D = Desired reaction; I = possible interfering reaction.Sodium In the first investigation by Anderson et aZ.l using essentially 14-MeV incident neutrons, two subjects were irradiated while lying on a couch approximating to an arc of a circle of 1.1 m radius centred on the target of a Cockcroft - Walton accelerator.The subjects and the man- like model were enclosed by polyethylene sheets and polyethylene bottles filled with water were placed beside the legs so as to reduce the loss of slow neutrons. The subjects were given a bilateral and the man-like model a unilateral irradiation.The phantom contained 105 g of sodium and 105g of chlorine. The induced radioactivity was measured in a whole body counter, the duration of the count being 35 min. Further measurements were made a t about 5 h (when BCl had decayed to about 0.3 per cent.) and at 24 h. The results of this experiment showed an average whole body sodium content in healthy adult males of 73.3 g per 70 kg body weight.In the light of subsequent experiments,2 this218 ACTIVATION ANALYSIS Proc. AnaZyt. Div. Chem. SOC. sodium value could be reduced by 0.102 g for each gram of magnesium present in the subject (on the assumption of 35 g of magnesium per 70 kg body weight) produced by the reaction 24Mg(n,p)24Na. The revised value for sodium then becomes 69.9 g per 70 kg body weight.The 24-h exchangeable sodium on the same two subjects gave a mean value of 74-8 g per 70 kg body weight. The results further suggested that the then accepted total body content of sodium of 105 g had been over-estimated by chemical analysis and hence there was a much smaller difference between total and exchangeable components (at the time it seemed from these results as if there was no difference).The smaller value for total body sodium obtained by TBNAA than that previously held was confirmed by the Birmingham group in 1968, who used a cyclotron as a neutron source.3 The resulting neutron spectrum was continuous from 0.1 to 8-0 MeV with a peak of 3.5 MeV. This choice of neutron energy avoided any serious interfering reactions. They also measured exchangeable sodium and found that in this and further experiments 19 4 per cent.of total body sodium was non-exchangeable. Subsequent work by the King’s College group4 on six male volunteers and the Seattle group5 on five male volunteers, together with various measurements in diseased states by the Brook- haven group, has shown that total body sodium by TBNAA is about 80 g per 70 kg body weight, of which in normal adults up to about 25 per cent.may be exchangeable. Chlorine The total body content of chlorine is determined from the reaction 37Cl(n,y)33Cl. The possible contribution of the 2.16-MeV y-ray from 38mK from the reaction 39K(n,2n)83mK on the 2.15-MeV y-ray from 38Cl was allowed for by preferential decay, but with a resulting loss of statistical accuracy of counting, when the first experiment was performed in 1964 by Anderson et aZ.l As with sodium, however, the estimated chlorine content of 73-5 g per 70 kg body weight was well below the accepted value of 105 g.The possible interfering reactions were subsequently shown by Battye et aL2 to contribute only a few per cent. to the activity from the desired reaction when using neutrons of 14-MeV energy.The contribution of interfering reactions can be minimised even further by using incident neutrons of energy lower than 14 MeV. The TBNAA of chlorine does not appear to have been so popular as the TBNAA of other elements-an indication not so much of difficulties with this particular element (although some difficulties may exist) but rather the lack of knowledge of the role of chloride in diseased states.Values for total body chlorine that have been reported for various diseased states have ranged from 76.0 to 92.4 g per 70 kg body Calcium A peak at about 3.1 MeV was seen in the post-irradiation spectra of the two subjects irradi- ated in 1964 by Anderson et aZ.l This peak was attributed to 49Ca from the reaction 48Ca(n,y)- 49Ca.Although the irradiated man-like phantom on this occasion contained no calcium to serve as a standard, the calcium content of each subject was derived by comparison with the sodium content and its induced 24Na. The two values obtained for total body calcium were 1330 and 1090 g per 70 kg body weight. The possibility of using TBNAA for the determination of total body calcium content aroused particular clinical interest because it would provide a direct method of ascertaining the progress of treatment on various bone diseases.The isotope dilution technique, using 45Ca and/or *Ta, had not found particular favour because of the lengthy course of sampling involved and the controversial compartmental analysis necessary to elucidate the results. Calcium balance procedures are also lengthy and expensive and the analyses are laborious.Radio- graphy is relatively insensitive in detecting changes in calcification, 25-30 per cent. deminerali- sation being necessary to produce clear changes in the X-ray pictures. With 14-MeV neutrons there is an interfering reaction, namely the production of s7S with a half-life of 5.0 min and a y-ray of energy 3.10 MeV, both close to the values for 49Ca of 8.75 min and 3-07 MeV, respectively.The contribution of the 37S activity, however, is only a few per cent. of the calcium count and can easily be allowed for. Three groups of workers at Birmingham, Seattle and Brookhaven have carried out extensive studies on patients with various bone diseases. The Birmingham group have validated theAugust, 1975 ACTIVATION ANALYSIS 219 relevance of sequential whole body calcium measurements in a number of conditions, and have stated that the method can be applied with confidence to conditions in which the direction of change is unpredictable, such as renal dialysis.8 The American groups have also published extensively on calcium determinations by TBNAA, and express their results in absolute terms of calcium.The mean total body calcium of eight normal men was 1093g per 70 kg b~dyweight,~which for this element agrees favourably with the ICRP value of 1050 g per 70 kg.10 An interesting recent development in the TBNAA of calcium has arisen from a feasibility study reported by Palmerll of measuring 37Ar in expired air. The 37Ar is produced by the reaction 40Ca(n,a)37Ar, and is assayed in preference to the 41Ar from the reaction 44Ca(n,~)41Ar because of the interference from the reaction 41K(n,p)41Ar.This development is considered in the following paper.12 Phosphorus Fast neutrons will interact with phosphorus to produce 28Al by the reaction 31P(n,a)28A1. The %A1 has a half-life of 2.30 min and emits a 1.78-MeV y-ray for each disintegration. The reaction has been used to measure the total body content of phosphorus in small animals where uniformity of flux can be assured throughout the body thickness, and in humans where, however, the use of the method is more difficult because of the larger body size.The values that have been published for humans6J3 were low compared with the values given for standard man, but whether this was due t o the method or the diseased state of the patients is not certain. At present, the main interest in total body phosphorus measurements arises from the possibility of its use as a substitute for calcium in determining total body bone mass.However, as only about 66-75 per cent. of the total body phosphorus resides in the skeleton compared with 99 per cent.of the total body calcium, it will never be as good an indicator of bone mass as calcium. Nitrogen The first method for measuring nitrogen in humans6 used 14-MeV neutrons to induce the reaction 14N(n,2n)13N. The 13N has a half-life of 10.08 min and emits two 0-51-MeV annihi- lation photons per disintegration . The counting of 13N annihilation photons has interference from 30P and some 13N is produced from oxygen by the reaction l6O(p,a)l3N.This reaction with oxygen is produced by protons formed from high-energy neutron collisions with hydrogen. From studies by Palmer and Nelp14 on beef tissue, less than 10 per cent. of the 13N will be produced from oxygen in the body but a correction for this interference must be made. A more recent method developed by the Birmingham groups measures the prompt 10-%MeV y-ray emitted when 14N captures a thermal neutron.Upon thermal neutron capture by 14N in the reaction 14N(n,y)15N, about 15 per cent. of the excited 15N nuclei decay directly, emitting 10-%MeV y-rays. As the y-rays resulting from thermal neutron capture in the major body elements are mostly of energies below 7 MeV, it is possible to measure the body nitrogen content by monitoring the 10.8-MeV y-rays with a large sodium iodide crystal spectrometer. The irradiation and counting are carried out during alternating short periods while the patient remains in a fixed position.The neutrons from the cyclotron are pulsed in repetitive cycles consisting of irradiation for 10 ,US followed by an interval of 140 ps.After the neutrons are turned off, the counting is performed during the next few hundred microseconds as the neutrons are thermalised and captured within the body. Sequential studies of patients to determine the magnitude and rate of change of body nitrogen have been undertaken using this reaction, although determination of the absolute value is not yet possible. The only published results for total body nitrogen in humans are those of Cohn and Dombrow- ski and, like the phosphorus results, were obtained in conjunction with total body calcium, sodium and chlorine measurements.The uniformity for nitrogen activation was poor as irradiation conditions were optimised for thermal neutron activation. The total body nitrogen results6,l3 were high when compared with ICRP values for standard man.To summarise, a number of centres are now actively pursuing the technique of TBNAA since it was introduced 10 years ago. It has found application in clinical investigations of many220 ACTIVATION ANALYSIS Proc. Analyt. Div. Chem. SOC. diseased states, where it has been used for the determination of total body content of sodium, chlorine, calcium, phosphorus and nitrogen.Modifications and improvements in the technique are still being implemented and may reduce the irradiation dose necessary for the deter- mination of the major body elements. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. References Anderson, J., Osborn, S. B., Tomlinson, R. W. S.. Newton, D., Rundo, J.. Salmon, L., and Smith, Battye, C.K., Tomlinson, R. W. S., Anderson, J., and Osborn, S. B., “Nuclear Activation Tech- Chamberlain, M. J., Fremlin, J. H., Peters, D. K., and Philip, H., BY. Med. J., 1968, ii 583. Anderson, J., Battye, C. K., Osborn, S. B., Tomlinson, R. W. S , Fry, F. A., andNewton, D., “Nuclear Rudd, T. G., and Nelp, W. B., “In Vivo Neutron Activation Analysis,” I.A.E.A., Vienna, 1973, p.105.Cohn, S. H., and Dombrowski, C. A., J . NU^. Med., 1971, 12, 499. Cohn, S. H., Roginsky, M. S., Aloia, J. F., Ellis, K. J., and Shukla, K. K., J . Clin. E ~ ~ o G Y . Metab., Fremlin, J. H., and Chamberlain, M. J., “In Vivo Neutron Activation Analysis,” I.A.E.A., Vienna, Nelp, W. B., and Palmer, H. E., “In Vivo Neutron Activation Analysis,” I.A.E.A., Vienna, 1973, International Commission on Radiological Protection (ICRP), Report of Committee I1 on Permissible Palmer, H.E., “In Vivo Neutron Activation Analysis,” I.A.E.A., Vienna. 1973, p. 203. Ozbas, E., Chettle, D. R., Dabek, J., Ettinger, K. V., Fremlin, J. H., Prestwich, W. V., and Thomas, Aloia, J. F., Roginsky, M. S., Jowsey, J., Dombrowski, C. S., Shukla, K. K., and Cohn, S. H., J . Palmer, H. E., and Nelp, W.B., “ I n Vivo Neutron Activation Analysis,” I.A.E.A., Vienna, 1973, J. W., Lancet, 1964, ii, 1201. niques in the Life Sciences,” I.A.E.A., Vienna, 1967, p.573. Activation Techniques in the Life Sciences,” I.A.E.A., Vienna, 1972, p.571. 1973, 36, 742. 1973, p.13. p.193. Dose for Internal Radiation, London, 1959. B. J., Proc. Analyt. Div. Chem. SOL, 1975, 12, 220. Clin.Endow. Metab., 1972, 35, 543. p. 127. Argonaut: An (n,a) Reaction Used to Measure Calcium ln Vivo E. Ozbas,* D. R. Chettie," J. Dabekt K. V. Ettinger J. H. Fremlin W. V. Prestwich and B. J. Thomas University of Birmingham, P.O. Box 363, Birmingham, B15 2TT Department of Medical Physics, University of Aberdeen, Aberdeen, AB9 1AS Department of Physics, University of Birmingham, P.O.Box 363, Birmingham, B15 2TT Department of Physics, McMaster University, Hamilton, Ontario, Canada Department of Physics, University of Birmingham, P.O. Box 363, Birmingham, B15 2TT Ten years ago, Anderson et aZ.1 reported on the use of irt vivo neutron-activation analysis (IVNAA) as a means of determining elemental concentrations in living subjects. Calcium was one of the elements which they suggested might be measured in this way.Following this suggestion, several laboratories developed systems capable of monitoring human calcium le~els.2-~ These systems made use of the thermal neutron reaction 48Ca(n,y)49Ca, and de- tected the 3.07-MeV y-ray emitted from the decay of the 49Ca with a half-life of 8.7 min. More recently, Palmer and c0-workers5~~ investigated the feasibility of using the reaction 40Ca(n,a)37Ar to measure calcium.This paper describes an IVNAA system that has been established at Birmingham to use this reaction for calcium measurements. The 37Ar decays with a half-life of 34.3 d, emitting 2.62-keV Auger electrons and X-rays. As the energy is low, the 37Ar cannot be counted inside the body but, being chemically inert, it is easily released from the body and exhaled.*Department of Physics. t Depar tment of Experimental Pathology.August, 1975 ACTIVATION ANALYSIS 221 The method employed can be conveniently divided into four phases. Firstly, the subject is prepared for irradiation by being given pure oxygen to breathe, which has the effect of depleting the nitrogen concentration in the subject's lungs.The irradiation is carried out with neutrons produced by the reaction 9Be(3He,n)11C. The 3He particles are accelerated to 30 MeV in the 60-in Nuffield cyclotron. The second aspect of the method is the collection of the exhaled gases from the subject. This starts at the beginning of the irradiation and continues for some time. The subject, whether animal or human, is in a closed breathing circuit that can be sampled periodically.lo3 TABLE I REPRODUCIBILITY FOR HAMSTER : I c ' Run Flux monitor No. counts 1 121 158 2 145 575 3 119 102 4 131 584 5 133 683 Mean .. Reproducibility 37Ar counts 16 409 19 064 16 019 16 769 17 488 .. .. .. .. 37Ar counts monitor counts 0.1354 0.1309 0.1344 0.1271 0.1308 0-132 f. 0.003 2.25% Thirdly, the exhaled gases must be purified so as to leave only the various isotopes of argon and possibly trace amounts of other inert gases.This is necessary because any electro- negative gas impurities will impair the counting of the 37Ar. A sample is stored on a cooled activated charcoal trap, and is slowly released through a furnace containing 7.5 kg of copper turnings heated to 540 O C , a molecular sieve (type 3A) is used as a drying agent and any residual carbon dioxide or water is removed in the cold trap and the phosphorus pentoxide trap.Finally, the nitrogen, already depleted by the use of pure oxygen as a breathing gas, is removed in a furnace containing about 150 g of calcium turnings heated to 600 "C. A second furnace containing copper removes trace amounts of oxygen.c E 8 'O'i 0 Fig. 1. Exhalation graph for rabbit.222 ACTIVATION ANALYSIS Proc. AnaZyyt. Div. Chem. SOC. The now purified sample is counted internally in a gas proportional counter. A 9+1 argon - methane mixture is used as a filling gas in the counter, which is, typically, filled to a pressure of 560 torr, and carries a potential of 2500 V on its anode wire. The reproducibility of the system has been investigated by performing measurements on the same mature hamster five times during a period of 10 d.The results of these measure- ments, which had a coefficient of variation of 2-25 per cent. are summarised in Table I. The rate at which the 37Ar is exhaled from the body has been measured for a rabbit and a man. The rabbit’s exhalation graph is shown in Fig.1. These data are consistent with an exponential exhalation with a half-life of about 20 min. Fig. 2(a) shows the over-all human exhalation graph and Fig. 2(b) shows the same data plotted on an expanded time scale. An exponential fitted to the first five data points has a half-life of 21 min, while the longer lived component could represent either a second exponential with a half-life of the order of 20 h or a nearly constant level with respect to the 36 h covered by the experiment.The final part of the method is the counting of the 37Ar. X X X X 0 500 1000 1500 2000 0 50 100 150 Time/m in Fig. 2. Human exhalation graph. (u) J.H.F., 2 d ; and (b) J.H.F., 2 h. This technique can usefully be compared with the already established 48Ca(n,y)49Ca tech- nique.Fig. 3 summarises the nuclear properties associated with the two techniques. It can be seen that 40Ca is much more abundant than 48Ca. The cross-sections for the two reactions are not directly comparable. The 0.1-b cross-section quoted for the 40Ca(n,a)37Ar reaction is an estimate of the effective cross-section for the incident neutron spectrum, taking into account the variation of cross-section with energy.The thermal neutron capture cross- section is quoted for the 4sCa(n,y)49Ca reaction but the effective cross-section for any non- U = 1-1 b 0=0*1 b 0.185% 48 Ca(n,~)~’Ca tX = 8.7 min 97% 40Ca(n,a.)37Ar tY2 = 34.3 d abundant 93% 2-6-keV electron 7% CI X-ray I abundant 92% 3-08-MeV Y 37Ar I 49sc Fig. 3. Nuclear properties associated with the two techniques.August, 1975 ACTIVATION ANALYSIS 223 thermal incident neutron beam must be less than 1.1 b.The long half-life of 37Ar means that it is impracticable to count more than 2 per cent. of the induced activity, while, allowing for transfer of the subject from irradiation area to counting area, about 40 per cent. of the induced activity of 49Ca can be monitored. The over-all detection efficiency for 37Ar depends only on the efficiency of transfer of the 37Ar from the body to the counter, because once in the counter it will be detected with effectively 100 per cent.efficiency. The efficiency for the detection of 49Ca depends on the intrinsic photopeak efficiency of the sodium iodide scintillator and on the geometrical arrangement. These two factors give a combined efficiency of about 1.5 per cent.for an array of 54 6- x 2-in crystals.' Taking all the factors together and assuming that 50 per cent. of the 37Ar is collected and that it is counted for 12 h, the 37Ar method should require a dose 40 times less than the 48Ca method in order to obtain statistically similar information. Another aspect worthy of comment is the shape of the exhalation curve. This contains information on the transport of the 37Ar out of the body and it is possible that this information could be usefully interpreted. If the long-lived component represents a substantial proportion of the total induced activity, absolute measurements of total body calcium may be difficult to obtain, but this should not impair the usefulness of sequential measurements of calcium on the same patient. One of us (D.R.C.) is in receipt of a scholarship from the Wellcome Trust. References 1. Anderson, J., Osborn, S. B., Tomlinson, R. W. S., Newton, D., Rundo, J., Salmon, L., and Smith, 2. Palmer, H. E., Nelp, W. B., Murano, R., and Rich, C. R., J. Nucl. Med., 1967, 8 268. 3. Chamberlain, M. J., Fremlin, J. H., Peters, D. K., and Philip, H., BY. Med. J., 1968, ii, 581. 4. Cohn, S. H., Dombrowski, C. S., and Fairchild, R. G., Int. J . Appl. Radiat. Isotopes, 1970, 21, 127. 5. Palmer, H. E., J. Nucl. Med., 1973, 14, 522. 6. Lewellen, T. K., Nelp, W. B., and Palmer, H. E., J . Am. Nucl. Soc., 1974, 18, 97. 7. Cohn, S. H., Dombrowski, C. S., Pate, H. R., and Robertson, J. S., Phys, Med. Biol., 1969, 14, 645. J. W., Lancet, 1964, ii, 1201.

ISSN:0306-1396    

DOI:10.1039/AD9751200216

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

August, 1975 ACTIVATION ANALYSIS 223 Toxicological Applications of Neutron-activation Analysis J. D. Cross, I. M. Dale and H. Smith West of Scotland Health Boards, Department of Clinical Physics and Bioengineeving, 11 West Graham Street, Glasgow, and Department of Forensic Medicine, Glasgow University, Glasgow Thermal neutron-activation analysis has long been recognised as a useful tool for trace element studies in toxicology.Its main advantages are its sensitivity, low contamination risk and the possibility of correcting for errors due to loss during any chemical separation procedure. This is achieved by the use of inactive carrier elements and the need for specialised micro- chemical techniques is thus eliminated. This paper describes some of our recent applications of neutron-activation analysis to three elements when ingested by people in excess of normal intake.Two of the elements (copper and chromium) are essential to life and one (bromine) is as yet unclassified. Three recent deaths in the Glasgow area were investigated and trace element levels compared with “normal” levels. “Normal” tissues were obtained from healthy subjects who had died in Glasgow as a result of violence.The subjects investigated were as follows- (1) A 64-year-old farmer who had died 36 h after ingesting a corrosive solution containing 30 per cent. of copper sulphate and 30 per cent. of sodium dichromate, intended for use as a wood preservative. Death was due to “corrosive poisoning.” (2) A 71-year-old housewife who had died of heart failure.A routine drug screen revealed therapeutic levels of carbrital, a sedative containing bromine. (3) A 69-year-old housewife known to be taking carbital tablets was found dead in her home. Therapeutic levels of the drug were found. Death was due to “myocardial degeneration.”224 ACTIVATION ANALYSIS PYOC. Analyt. Div. Chem. SOC. Techniques All tissue samples were vacuum dried and irradiated for 1 d at 6 x 10l2 neutrons cm-2 s-1 in the PLUTO reactor at Hanvell.Bromine and chromium were determined in the tissues by instrumental thermal neutron- activation analysis. Several days’ decay was allowed before measuring the y-spectra using a 60-ml germanium (lithium) detector. Copper was determined in tissue by using a chemical separation pr0cedure.l Applications Case 1 with mean normal values.The copper and chromium contents of the tissue samples are given in Table I, together TABLE I COPPER AND CHROMIUM (p.p.m. DRY MASS) IN HUMAN TISSUE Copper Chromium P- Sample case Tissue Case tissue Stomach Lung Heart Kidney Whole dry blood Brain Liver Spleen Hair root Hair length Urine 33.4 11.2 3.7 17.5 5.5 62-6 55.7 3.8 38.7 1.5 238 12.6 9.5 16.5 14-9 9.5 23.9 25.5 6.8 } 23.1 0.1 76.6 0.4 36.6 2.4, 0-2 9.3 0.2 157 0.2 1.9 0.1 18.9 144 33-1 13.1 Table I shows that, excluding urine, hair root, liver and brain, the copper content of the samples analysed is within the normal range.The chromium analysis shows elevated levels throughout the organs. Cases 2 and 3 Bromine-containing sedatives have been relied upon very heavily in the past in the treat- ment of epilepsy. Today they can still be bought by the public despite known cumulative effects. This accumulation is demonstrated in Table 11, which gives the bromine levels in a selection of the 19 tissues analysed from each case.All tissues show elevated levels. TABLE I1 BROMINE (p.p.m. DRY MASS) IN HUMAN TISSUE Sample Kidney Liver Heart Thyroid Stomach Case 2 Case 3 “Normal” subjects (mean) 695 188 27.7 781 91.2 11.5 482 75.1 15.6 868 180 14-3 1492 65.1 28.6 Discussion Most ingested copper is excreted via the faeces.Any absorbed copper is transported in the blood attached to albumin and is stored by the liver until incorporated into newly synthesised ceruloplasmin.2 In Case 1, the amount of copper ingested was massive in comparison with normal dietary intake.We might therefore expect that the binding sites in the liver would become temporarily saturated, giving a situation analogous to that found in Wilson’s disease. In this disease, there is insufficient ceruloplasmin present to remove the copper fromAugust, 1975 ACTIVATION ANALYSIS 225 the liver, and accumulation also occurs in the brain, skin and pancreas.After saturation point is reached, copper is detached from albumin in the kidneys and excreted in the urine. This is consistent with the findings of elevated copper in the liver, brain and urine of case 1. It appears from the only slightly elevated liver copper content at death, however, that most of the excess of copper had been removed by cemloplasmin during the 36-h survival period.In complete contrast to copper, chromium is concentrated throughout the organs owing to its high absorption. Dichromates in particular are reported as being absorbed3 to extents greater than 70 per cent., which probably accounts for their toxicity. Taken in physiological amounts, chromium is known to be transported in the blood attached to tran~ferrin.~ On ingestion of larger amounts, it becomes specifically attached to, and transported by, red cell proteins.It is thought to be responsible, together with magnesium, for the activation of phosphoglucomutase in the breakdown of glycogen into glucose. Bromides are also known to be readily absorbable and diffusable into the soft ti~sues.~ There is no evidence to support previous reports that bromide is preferentially absorbed by the thyroid, albeit to a lesser extent than i ~ d i d e .~ Conclusion In this study, copper has been found to exhibit low absorption and rapid biological proces- sing, whereas chromium and bromine exhibit high absorption and concentration in the tissues. References 1. Fell, G. S., Smith, H., and Howie, R. A., J. Clin. Path. 1968, 21, 8.2. Davies, I. J . T., “The Clinical Significance of the Essential Biological Metals,’’ Wm. Heinemann 3. Spector, W. S., “Handbook of Biological Data,” Saunders, Philadelphia, 1956. 4. Hopkins, I. L., and Schwartz, K., Biochcim. Bzophys. Acta., 1964, 90, 484. 5. Bowen, H. J . M., “Trace Elements in Biochemistry,” Academic Press, London and New York, 1966. Medical Books Ltd., London, 1972.Biological Analysis with a Nuclear Microprobe J. A. Cookson and G. J. F. Legge" Nuclear Physics Division, Atomic Energy Research Establishment, Harwell, Didcot, Oxfordshire, OX1 1 ORA Most low-energy nuclear accelerators are now partly used on analytical studies in support of sciences other than nuclear physics. The analysis can take a number of different forms and in a number of instances positional information is obtained.This paper gives a short review of such analytical techniques with particular reference to biological applications, and also emphasises the role of the positional analysis that can be performed with a focused beam of ions-the nuclear microprobe. The Nuclear Microprobe Although positional analysis with collimated ion beams has been carried out in a number of laboratories,192 the collimators cause a number of difficulties, notably low beam intensity, slit scattering, cramped geometry and extra background.As a result of a decision at Hanvell in 1968, a well focused beam of 3-MeV protons was first produced. The system, which is currently being copied in a number of laboratories, has already been fully documented394 but a short description seems worthwhile.Because the ion beams have much higher energy and mass than the electron beams used in probes, focusing with normal electrostatic or cylindrical magnetic lenses is impracticable, and a system of quadrupole lenses is used. Fig. 1 shows the arrangement in which a collimator (about 20 pm square) selects a small part of the focused beam from a 3-MeV accelerator.The set of four quadrupole lenses produces a geometrical image of the collimator on target with a demagnification factor of 1 : 5-6. The available spot size is down to about 4 pm square for protons, deuterons or a-particles up to 3 MeV energy. *On leave from the University of Melbourne, Australia.226 ACTIVATION ANALYSIS Proc. Analyt. Div.Chem. SOC. Quadruoole Primary lenses Particle collimator - 20 pm 0 3-MeV protons t Microscope Fig. 1. Schematic diagram of the Harwell microbeam system. Three main analytical techniques are used with nuclear charged particles, both for broad area analysis and microprobe work : X-ray analysis, elastic scattering and nuclear reactions. These will be considered, together with some biological examples of their use.X-ray Analysis Analytical techniques using X-rays induced by electrons or photons are widely used and are rapidly being joined by charged particle induced X-ray analysis. Despite the cost of nuclear accelerator time, there is a special virtue of nuclear charged particles that makes them particu- larly suitable for simultaneous multi-element analysis using lit hium-drifted silicon X-ray detectors, viz., the low background and consequent high sensitivity that can be achieved when using protons or a-particle~.~ Because their mass is much higher than that of the elec- tron, nuclear particles give only a low bremsstrahlung background in addition to the charac- teristic X-rays that serve to identify the elements in a specimen.All elements above atomic number 12 can readily be determined with sensitivity, in the best instances, of better than 1 p.p.m.by mass. A number of laboratories have set up systems for the rapid analysis of specimens about 1 cm diameter on thin backings; e.g. , at the University of California, Davis, 1000 multi-element analyses are performed in 36 h using 18-MeV a-particles, a major interest being aerosols.6 For the analysis of biological materials, the form of the specimens varies, examples being 60 pm thick freeze-dried self-supporting sections of animal livers' and about 10 pm thick biological sections mounted on thin carbon foils.* The availability of a microbeam of 3-MeV protons makes this type of analysis possible on small regions of specimens.In an example of such a multi-element analysis from a region of a human blood smear containing a single erythrocyte, trace metals could be seen as well as larger concentrations of elements from sodium upwards.One means of studying positional analysis with the microbeam is to scan the beam con- tinuously across the surface of a specimen, recording the energy of each X-ray as well as the position of the beam when the X-ray was emitted.The distribution of elements across a diameter of human hair was obtained in this way.g The notable feature was the peaking of the copper concentration near the surface of the hair, which is probably explained by the significant amount of copper observed in the shampoo used on this particular hair. A more typical problem in biological analysis is to measure the distribution of elements within regions of prepared sections , and some exploratory application of the nuclear micro- probe to this work has been carried out at HarwelLlO The problems of specimen preparation were the same as those met in electron microprobe work, involving special washing techniques and vacuum drying, but the resulting specimens seemed to stand up well to the proton beam currents that were needed.Elastic Scattering Analysis In this technique, the energy spectrum of particles that have been Rutherford scattered from the specimen is recorded: the more energetic a scattered particle, the heavier is the nucleus by which it was scattered. The technique has most application in solid-state studies, where it can achieve very high sensitivity, such as the gold layer of only 1010 atoms cm-2 (2 x monolayer) on silicon, which can be measured by scattering of 2-MeV carbon ions.Il For biological analysis, it is more apposite to use thin specimens, and Jolly and WhiteI2 have achieved high mass resolution by using magnetic analysis of back-scat tered 22-MeV a-particles.They have analysed whole fish, human blood and cows' milk and claim that theAugust, 1975 ACTIVATION ANALYSIS 227 I L technique is most suitable for detecting heavy elements, for which a sensitivity of 10-6-10-9 in atomic concentration is achieved.Fig. 2 shows elastic scattering spectra obtained with solid-state detectors at 135" and 45" to a 3-MeV proton beam. At the backward angle, carbon, nitrogen and oxygen can be readily measured, while for detection at a forward angle the amount of hydrogen relative to carbon With the microbeam facility, positional analysis is and heavier elements can be measured.also available. 2500 2000 - a, c z J 1500 L al Q v) u 5 1000 0 0 500 Channel number C 0 100 200 Channel number i Fig. 2 . Elastic scattering of 3-MeV protons (a) a t 135" from a Chinese hamster lung cell on thin formvar, and ( b ) a t 45" from thin formvar.Nuclear Reaction Analysis The special ability of this technique is in measuring low-2 elements, even in a high-2 matrix. Such analysis is often difficult and inaccurate by other methods, e.g., the electron probe, but there is almost always a nuclear reaction available that is very specific to a chosen light element.A major use of the Harwell microbeam is in studying variations in concen- trations of light elements across sections of metallic specimens using such nuclear reactions as 12C(d,p)13C with the emitted protons being detected.l3 A comprehensive review of useful nuclear reactions has been given by Bird et aZ.14 but few biological applications are listed. Among the few examples are Ricci's measurements of concentrations of 12C, l3C and l5N in human lung, brain and E.coli by detection of y-rays from (p,y) and (p,ay) rea~ti0ns.l~ This is an example of the special ability of the technique to distinguish between different isotopes of the same element. The lgF(p,ay)l60 reaction has been used to study the fluorine concentration in tooth enamel.16 This is an example of positional analysis using a nuclear resonance, as the yield of 6.13-MeV y-rays has a strong peak near a proton energy of 670 keV.The fluorine concentration profile was obtained by measur- ing the y-intensity as a function of the beam energy and hence the distance into the surface of the tooth at which the resonance energy was reached. Nuclear charged particle analysis of nitrogen in biological materials has been carried out by a number of workers.Apart from the 15N(p,ay!12C reaction already mentioned, the 14N(p,d)- 13N reaction using 185-MeV protons has been tried,17 but the most promising reactions from a practical point of view are 14N(d,p)15N and 14N(d,a)12C, both of which emit energetic charged particles and have high cross-sections. Sundqvist et aZ.l* have cut wheat grains in half and measured the high-energy proton and a-yield when the centre of an exposed section was bombarded with 6-MeV deuterons.Comparison of nitrogen concentrations given by this technique and the standard Kjeldahl chemical technique suggested a relative accuracy of about 6 per cent. The 14N(d,p) reaction was applied to sections of grains of rice at Hanvell, with 2-MeV deuterons focused to a spot about 0.05 mm across and then scanned across a diameter of the mid-section of a grain.Fig. 3 shows how clearly the high nitrogen concen- tration in the aleuron surface layer of the rice can be measured. Such a strong variation in228 ACTIVATION ANALYSIS PYOC. Analyt. Div. Chem. SOC. nitrogen concentration poses a problem for attempts to carry out rapid measurements of the average nitrogen concentration of grains with nuclear charged particles.1 2 3 4 5 D istance/mm Fig. 3. Distribution of nitrogen across the diameter of a grain of rice measured with the 14N(d,p) 15N reaction. Conclusion Although the techniques that have been described, and particularly the use of the microbeam, are still very new, some special features have emerged and potential uses can be seen.These are summarised in Table I. TABLE I APPLICATIONS OF NUCLEAR MICROPROBE TECHNIQUES Elements anal ysed Sensitivity Special virtues Biological Applications- Large areas p- or a-induced p or a elastic X-rays scattering All are possible. Best sensitivity z >11 for high Z 0.1 p.p.m. for 10-6-10-9 atomic best cases concn.for high 2 Very rapid. Can analyse Many elements hydrogen. a t once Many elements a t once Multi-element analysis of thin sections or deposits on foils Nuclear reactions Low z Very variable. Down to 0.1 p.p.m. Depth profiles possible down to 10 nm resolution. Isotopes distinguished Special cases, e.g., N, F With microbeam. Yields from single cells or variations within large cells We gratefully acknowledge the assistance of Mr.F. D. Pilling and of the IBIS accelerator team. References 1. Pierce, T. B., Peck, P. F., and Cuff, D. R. A., Analyst, 1970 92, 143. 2. Price, P. B., and Bird, J. R.. Nucl. Instrum. Meth., 1969, 69, 277. 3. Cookson, J. A., and Pilling, F. D., Rep. U.K. Atom. Energy. Auth., AERE-R6300, 1970.A ztgust, 1975 ANALYTICAL TECHNIQUES USED IN INDUSTRY 4.5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 229 Cookson, J . A., Ferguson, A. T. G., and Pilling, F. D., J . Radioanalyf. Chem., 1972, 12, 39. Johansson, T. B., Akselsson, R., and Johansson, S. A. E., Nucl. Instrum. Meth., 1970, 84, 141. Hamson, J. F., and Eldred, R. A., Adv. X-ray Analysis, 1973, 17, 560. Kemp’lK., Jensen, F. P., and Merller, J . T., Rep. Dan. Atom. Energy Commn.. Riso M-1732, 1974. Campbell, J . L., Herman, A. W., McNelles, L. A., Orr, B. H., and Willoughby, R. A., Adv. X-ray Unpublished work; part of a study carried out on behalf of the Home Office Central Research Estab- G. J. F. Legge, to be published. Abel, F., Amsel, G., Bruneaux, M., Cohen, C., Maurel, B., Rigo, S., and Roussel, J., J . Radioanalyt. Jolly, R. K., and White, H. B., Nucl. Instrum. Meth., 1971, 97, 299. Pierce, T. B., McMillan, J . W., Peck, P. F., and Jones, I. G., Nucl. Instrum. Meth., 1974, 118, 115. Bird, J. R., Campbell, B. L. and Price, P. B., I.A .E.A. Atom. Energy Rev., Vienna, 1974, 12, 275. Ricci, E., Analyt. Chem., 1971, 43, 1866. Mandler, J. W., Moler, R. B., Raisen, E., and Rajan, K. S., Thin Solid Films, 1973, 19, 165. Johansson, A., Larsson, B., Tibbell, G., and Ehrenberg, L., Proceedings of Panel on New Approaches Sundqvist. B., Gonczi, L., Bergman, R., and Lindh, U., J . Radiat. Isotopes, 1974, 25, 277. Analysis. 1973, 17, 457. lishment, Aldermaston, Berkshire. Chem., 1973, 16, 587. to Breeding, I.A.E.A., Vienna, 1969, p. 169.

ISSN:0306-1396    

DOI:10.1039/AD9751200223

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

A ztgust, 1975 ANALYTICAL TECHNIQUES USED IN INDUSTRY 229 Analytical Techniques Used in Industry The CS Annual Chemical Congress, with the central theme of “A View Towards the 21st Century,” was held at the University of York from April 7th to l l t h , 1975. The Analytical Division organised a Symposium entitled “Analytical Techniques Used in Industry” on April 9th and loth, and the following are summaries of three of the papers presented.The Fourth Theophilus Redwood Lecture by Professor Petr Zuman appeared in full in the July issue (p. 199). Developments in the Analytical Control of Iron and Steelmaking T. S. Harrison British Steel Corporation, Scunthorpe and Lancashire Group, P.O. Box No. 1, Scunthorpe, South Hztmberside, DN16 1BP Within the works of the UK iron and steel industry, which comprise the public and private sectors, wide ranges of iron and steel products are made.The purpose for which the customer requires steel determines its physical properties, which, in turn, are governed by chemical composition. Material is therefore ordered to physical and chemical specifications in which tolerances are nowadays very close. Composition control over all stages of the manufacturing process is necessary and embraces raw materials, intermediates, the final rolled product and a range of ancillaries, for both opera- tional and commercial purposes.Samples should properly represent the bulk material and be suitably prepared for analysis. Process control involves shifts and contributory analysis day work; chemical and physical techniques are used in each.Major advances in metallurgical analysis were made by Vaughan, who developed absorptio- metric techniques for use on the Spekker instrument, Barker, who introduced spectrographic principles, and Walsh, who laid the foundations of atomic-absorption spectrophotometry. Further investigation and application of absorptiometry produced the spectrophotometer and a range of British Standard methods for both familiar and more uncommon elements down to low levels.As with the photographic spectrograph, this type of instrument is most useful in “post mortem” day work as modern steelmaking processes demand faster control techniques. Such was provided by the direct reader, developed by Hasler, in which the photographic plate was replaced with a system of photomultipliers, arranged in pre-set positions, which230 ANALYTICAL TECHNIQUES USED IN INDUSTRY Proc.Analyt. Div. Chem. SOC. recorded incident light energy via electronic means as readings on a scale. For iron and steel, however, the light energy of the principal wavelengths of carbon, phosphorus and sulphur is absorbed by air and so optical paths were designed in vacuo, the spark stands being flushed with argon.Such air and vacuum path emission instruments, which, on initiation of the dis- charge, would analyse metal or “oxide” materials for the desired constituents within a minute or so, were then installed, primarily for production control, on an extensive scale and so occurred a major revolution within the industry.Special air-conditioned rooms were built within the stage or central laboratories, to which samples were despatched from the production units by special carriers in a rapid pneumatic tube system. Machines for the cutting and surface preparation of metal samples and the pulverisation of ores and slags were provided in an adjoining area. But while routine chemical analysis has thus been superseded, the instru- ments are calibrated and regularly checked against standards prepared by specialist chemists using British Standard methods.Atomic-absorption spectrophotometry, further examined and applied to metallurgical analysis by several workers, among them Elwell and Gidley, West, Price and Ottaway, appealed to us by virtue of its selectivity, sensitivity, simplicity and speed and offered con- siderable savings in manpower, materials and time for a moderate financial outlay.The analytical potential of this new technique was soon realised and its adoption has had a major effect on the capability and productivity of our day laboratories, making available consider- ably more information with proportionally small additional effort . Working procedures have been developed for iron and steel, ores, slags, refractories, waters, effluents and lubricants and a bench manual has been compiled in our laboratory.Besides emission, X-ray fluorescence spectrometry is now used extensively in the analysis of metals by examination of a lapped surface, ferro-alloys after compaction and oxide materials preferably after fusion to break down the crystalline structure and so overcome mineralogical effects. Even so, in iron ores, slags and refractories, interelement effects have raised difficul- ties which, fortunately, have recently been overcome by Hughes.Initially in the Swindon Laboratories and now in the Research Centre, General Steels Division, he developed a correc- tion system based on interference a-factors, which he obtained by the examination of syn- thetic materials.By incorporating this information in the program of an adjacent dedicated computer, we can now determine several elements in unknown samples that have been similarly treated. Fusion of each with five times its mass of lithium tetraborate in a 95 + 5 platinum - gold crucible gives, when cast on a tray of the alloy and air cooled, a bead, the under- side of which is subjected to the X-ray beam.For routine work, a Schoeps apparatus is useful for bead preparation. The adoption of the rapid L.D. steelmaking process requires rapid control analysis in a laboratory close to the stage. Hence on the modern “Anchor” plant in Scunthorpe the laboratory was sited centrally facing the three furnaces so that furnace “bath” samples can be delivered to the preparation room quickly by hand.Adjacent to the hatch is a series of tube terminals relating to more distant iron and steel sampling stations, a cooling sink, de-burring machine, grinding, cutting, milling, drilling and linishing machines and a pulveriser for slag. Suitably prepared metal samples are transferred by hatch to the spectrograph room, which houses three vacuum direct readers, the latest having a dedicated computer, teletype machine and automatic link with the large melting shop computer next door.A supplementary manual data link is also provided. A third, smaller, room contains a fume chamber for chemical slag analysis and modern high- frequency combustion furnaces linked with analysers based on thermal conductivity prin- ciples for the determination of carbon and nitrogen in steel.Oxygen is similarly determined elsewhere. For sulphur, the furnace is connected to an automatic titration unit. Carbon and sulphur are also determined, in other works, by infrared measurement principles. Modern steelmaking also demands more rapid sampling techniques than the former “spoon and pour” method in which carbon was lost when pouring the molten steel into the open mould.While this is retained for iron sampling, commercial immersion-type samplers are used for steel “bath,” “pit” and “concast” samples and incorporate a suitably shaped mould containing aluminium wire for “killing” the steel prior to solidification. These tubular cardboard devices are attached to a long iron bar for immersion, which is withdrawn after a few seconds, the mould stripped and the sample conveyed to the laboratory while still hot.August, 1975 ANALYTICAL TECHNIQUES USED I N INDUSTRY 23 I Emphasis on the rapid determination of carbon in the steelmaking bath has also prompted the introduction, on the stage, of an apparatus based on the depression of the liquidus arrest point of molten steel during cooling and solidification.The steel is spoon-poured into a sand mould cartridge containing a platinum - rhodium thermocouple connected to a potentiometer recorder. After “killing” with aluminium, cooling is followed on the recorder and the arrest point noted and related to a calibration graph prepared from observations on samples of known carbon contents.Rolled steel product material, particularly plate that can be cut to suitable sizes, is analysed by emission spectrometry but problems are posed by metallurgical structural effects, e.g. , on sulphur, and sample dimensions and shape, e.g., variable diameter of rods. These problems are overcome by melting compacted millings or drillings, or small solid pieces, with an electric arc in an atmosphere of argon.A circular plate, capable of rotation, contains 12 depressions for samples, aluminium wire is added to each melt and, after cooling, a homogeneous bead is obtained. The calibration graph is obtained by taking chemically analysed drillings through the process. Depending on requirements, drillings can also be analysed chemically, for which purpose the AutoAnalyzer and atomic absorption are invaluable aids.The rapid determinations of gases in steel are of increasing importance and the conventional glassware is being superseded, apart from referee requirements, by the commercial instrumenta- tion already mentioned, which is robust, portable and simple to operate within the laboratory or on the stage. Besides total nitrogen, there is also considerable metallurgical interest in acid-soluble nitrogen and the various nitrides in steel, and investigation of their chemical determination is proceeding.Day chemists provide an invaluable back-up service, which includes the st andardisation of materials for the calibration of physical instruments and the checking of selected samples by reference chemical methods.Foreign ores and ferro-alloys are assayed for payment purposes, a wide range of materials is analysed by chemical and physico-chemical means and new methods are developed and adopted. In the ancillaries field, the analysis of blast furnace and coke oven gases, wash oils for naphthalene and crude benzole for benzene, toluene and xylene have been transferred to the chromatograph, while a similar method for the determination of phenol in effluents is being ‘examined.Current environmental needs have initiated the co-operative analysis of effluents and attempts to standardise on methods, the application of ion-selective electrodes to fluorine, ammonia and cyanide, exercises in monitoring and the identification and determination of oils in streams by infrared spectroscopy.Analytical research and development is pursued in the research centres, which include the former BISRA Laboratory in Sheffield, and works laboratories. Co-operative work com- menced before the last war and was eventually administered by the Chemical Analysis Com- mittee of BISRA, now BSC/BISPA. Over the years, many procedures developed by sub- committees have been approved and awarded BSI status.When international work began in 1960, the UK was represented by its Chairman, B. Bagshawe, and its methods used in the main as the bases of IS0 procedures. Recently, there has arisen a considerable interest in European committees and Euronorms. While a single spark analysis on a computer-controlled direct reader, with a high-frequency source unit, has been reduced below 30s, sampling, preparation and transfer take about 3min.Hence more rapid presentation should be studied. Improved forms of energy source such as the glow discharge lamp and laser beam should also be examined. Whenever possible, monitoring on-stream should be introduced in order to save the time of taking, conveying and preparing discrete samples, but when this must be done transfer to the analytical instrument should be automated.Within the laboratory, procedures will be required to cover smaller samples, additional ele- ments and lower levels. Besides the direct readers, other instruments should be further auto- mated and measures taken to improve the productivity and efficiency of our chemical labora- tories.The underside is then linished for sparking. For the future, a particular need is the acceleration of the steel bath analysis cycle.232 Laser Microspectrochemical Analysis ANALYTICAL TECHNIQUES USED IN INDUSTRY Proc. Analyt. Div. Chem. SOC. R. McGillivray I C I Fibres, Hookstone Road, Harrogate, North Yorkshire The first laser microprobe analyser was described by Brech and Cross1 in 1962 and, although laser microprobe instruments have been commercially available for nearly 10 years, the tech- nique of laser microspectrochemical analysis has been slow in becoming established, mainly because its scope and capabilities are not widely known.The technique has been used in ICI Fibres at Harrogate for about 5 years and has proved of value, especially for the analysis of particulate material in polymers.This particulate material is very varied in nature; it can range from “external” contamination, such as sand, concrete dust and fragments of metals and glass, to “internal” contaminants, such as catalyst residues, scale and metallic particles from the manufacturing plant, thermally degraded polymer and contaminants in the polymer intermediates.When poly(ethy1ene terephthalate) and nylon polymers are spun into fibre, particulate material of diameter similar to that of the filaments (i.e., 10-50 pm) can cause breaks, which adversely affect production and the quality of the yarn. It is, therefore, important to have rapid methods of analysis for this particulate material so that its origin can be ascertained and steps taken to eliminate it.Laser microspec- trochemical analysis has proved suitable for this purpose. Basic Principles and Equipment The basis of the technique is that a laser beam is focused on to a minute spot of material, thereby vaporising it. The vapour is further excited by an electric arc discharge and the emitted light passed through the optical system of a spectrograph, the resulting emission spectrum being recorded photographically.The equipment used at Harrogate is the Laser Microspectral Analyser (LMAI) manufactured by VEB Carl Zeiss Jena. For the first 3 years it was used with an uncontrolled neodym laser and for the last 2 years with a Q-switched ruby laser. With this equipment, particles or spots of material of size down to 5-10 pm can be analysed, the mass of material being vaporised being in the range 10-5-10-8g.The ele- ments detected are those normally detected by emission spectrography, i e . , those with relative atomic masses above 2, with the exception of nitrogen, oxygen, sulphur and the halogens, which would require the use of a vacuum spectrograph. The levels of detection vary with the elements, but generally they are in the range 0-1-5 per cent.with the uncontrolled neodym laser and about 10-100 times lower with the “passive” Q-switched ruby laser. Polaroid FilmrforlLaser Microspectrochemical Analysis In laser microprobe analysis, photographic glass plates that are fast and of fine grain are used, (e.g., Ilford LN or ORWO WU3) because the laser flash and the secondary excitation source have very short lifetimes (0.2 and 1 ms, respectively).The plates are 25 cm long and cover the spectral range 200-560nm. After firing the sample, it takes about 90min to develop, wash and dry the plates before the spectrum can be inspected. Recently, we have used Polaroid film (Type 57, 11.5 cm long and 9 cm wide), which has given spectra of quality comparable with that of the photographic plates. The advantage of this is that the sample can be placed on the specimen table of the laser microprobe analyser, fired on with the laser and the emission spectrum recorded and developed and be ready for inspection in about 1 min.This has the obvious advantage of greatly speeding up qualitative analysis. Although the Polaroid- film is only half the length of the glass plates, the spectral range covered is 250-490 nm for the medium quartz spectrograph used (Model Q24, VEB Carl Zeiss Jena) and for qualitative analysis this range is adequate.“Passive” Q-switching and its Advantages By Q-switching a solid-state laser, pulses of very short duration and very high power densi- ties are produced. This is achieved by inhibiting the gain of the laser crystal while the laser is pumped. In “active” Q-switching, this is carried out by mechanical or electro-opticalAugust, 1975 ANALYTICAL TECHNIQUES USED IN INDUSTRY 233 devices, which are complicated and expensive.In 1964, Soffer and Hoskins2 discovered that a solid-state laser can be Q-switched by the use of organic dyestuffs. This technique is referred to as “passive” Q-switching, which by its nature is inexpensive and free from trouble.In about 1970, VEB Carl Zeiss Jena introduced a “passive” Q-switched ruby laser device for their Laser Microspectral Analyser3 and this has been a major advance for the technique of laser microprobe analysis. Its greater power density makes it universally applicable to the ele- mental analysis of inorganic elements in both inorganic and essentially organic materials. In particular, it will vaporise quartz, glasses, ceramics and clear organic polymers, which the uncontrolled neodym fails to do.In addition, it gives improved sensitivity, the levels of detection being 10-100 times lower. This is important in the detection of small amounts of inorganic components in organic compounds.It fires much more reproducibly than the un- controlled system, thus enabling it to be used for semi-quantitative work. It can also be used for the analysis of surfaces,* for example, by defocusing the laser beam about 2 mm above the surface a layer of material about 400 pm in diameter and 2-3 pm thick is vaporised. Finally, its greater power means that it can be used as both vaporisation and excitation source and this has interesting possibilities for organic analysis.Our experiments have shown that the laser beam can be used with organic compounds to pyrolyse the sample and to excite the resulting molecules and radicals. In this way, it is possible to distinguish between Terylene a d nylon as the spectra are very different in the range 500-750 nm. During the past 2 years, since the Q-switched ruby laser was installed in the laser micro- probe at Harrogate, a very wide range of materials has been examined (metals, alloys, metal oxides, inorganic and organic chemicals, polymers, glasses, silicates, quartz and ceramics) and in no instance has the Q-switched laser failed to vaporise part of the sample.This demonstrates the universality of its application and this together with the speed of the analysis makes the technique very suitable for the examination of particle contaminants in polymers. References 1.2. 3. 4. Brech, F., and Cross, L., APPZ. Spectrosc., 1962, 16, 59. Soffer, B. H., and Hoskins, R. H., Nature, Lond., 1964, 204, 276. Moenke-Blankenburg, L., and Mohr, J.. Jenaer Jahrbuch, 1970, 195.Moenke-Blankenburg, L., and Quillfeldt, W., Jena Rev., 1972, 21, 91. Analysis in the Paint Industry-Present and Future t. A. O’Neill Paint Research Association, Teddington, Middlesex With an ever-increasing choice of component raw materials, the formulation of paints becomes continuously more complex and their analysis more difficult. Unless there is a corresponding development of new instruments and techniques, the chances of a successful analysis become more remote.Infrared spectroscopy, gas - liquid chromatography and atomic-absorption spectrophotometry have been of inestimable value to the industry but new techniques with equivalent impact are urgently needed for the future. Problems in the analysis of paints are mainly concerned with the three essential components, the pigment, the solvent and the binder, and with defects of the cured film.In the past, pigments were analysed by classical methods, but now by combinations of infra red spectroscopy, particularly in the longer wavelength regions, and chemical methods. For the determination of inorganic elements in a paint , atomic-absorption spectrophotometry is the most useful technique as it is usually possible to determine directly one element, e.g., lead, cadmium, mercury or antimony, irrespective of the over-all composition of the paint, a pro- cedure that is not normally possible by X-ray fluorescence or polarography.Gas - liquid chromatography is generally satisfactory for the analysis of the solvent although some consideration needs to be given to the best method for separating the solvent from the paint.The most tiresome complication is that white spirit, the most common paint solvent, shows a multitude of peaks, one of which may obscure the peak of another solvent that is also present. A simple method of determining the aromatic content of a white spirit would be valuable.234 ANALYTICAL TECHNIQUES USED IN INDUSTRY Proc.Avzalyt. Div. Chem. SOC. For the analysis of the binder, infrared spectroscopy is always the first technique to be tried. This method usually gives an indication of the main components but may not give much information on the minor components, so these generally have to be separated. The attenuated total reflectance technique is sometimes useful when the film is on a flexible substrate so that good contact can be made between the film and the prism, but the depth of penetration of the beam (a few microns) is too great for surface effects to be studied and not large enough to give a spectrum of the complete film.Laser Raman spectroscopy can sometimes give additional information to infrared spectro- scopy. For example, in conventional alkyd resins there is no strong infrared band character- istic of total unsaturation, but fortunately this is the strongest band in the laser Raman spectrum.l Nuclear magnetic resonance spectroscopy can give an informative picture of the distribution of protons in a complete resin, e.g., an alkyd resin, which contains nine types of proton, and is also valuable for identifying derivatives isolated from a resin.It can be used to follow the manufacture of an unsaturated polyester resin from ethylene glycol and maleic acid, indicating the progress of the esterification, the isomeration of maleic to fumaric acid and side reactions that lead to loss of unsaturation. Pyrolysis gas chromatography is useful for identifying polymers or copolymers that give the component monomers on pyrolysis.If used merely as a fingerprint technique, it is usually of value only for comparing samples, e.g., in forensic work. Thin-layer chromatography is mainly of value for identifying components isolated from a paint but, in conjunction with a recording densitometer, it can be used for the quantitative analysis of a partial glyceride mixture. Of the developing techniques, high-performance liquid chromatography offers the most promise for the analysis of complex mixtures but, apart from a few simple instances, e.g., the separation of phthalate ester plasticisers, it has not yet contributed greatly in the paint and polymer fields.Limitations of existing analytical techniques for identifying the full composition of the synthetic resins used in paints were demonstrated by the co-operative exercises organised by the Organic Coatings Section of IUPAC, relating to thermosetting acrylic2 and one-pack polyurethane resin^.^ Gel-permeation chromatography has been of exceptional value to the industry, giving in a single operation the molecular size distribution of the polymers used as paint binders, e.g., alkyd, epoxy and phenolic resins.Most polymers are examined in tetrahydrofuran solution but good results are being achieved at the Paint Research Association for water-soluble poly- mers in aqueous solution. The analysis of fumes from paint stoving operations, which are often the subject of local complaints, is being studied at the Paint Research Association. The fumes are collected in special adsorbent tubes, flashed off into a gas chromatograph and analysed by measuring retention times or, in difficult instances, by gas - liquid chromatography combined with infra- red or mass spectroscopy. Often, the only clue to the cause of blistering is compounds present in the blister or, in loss of adhesion, compounds found at the interface. Stains are a continuous problem: if discrete, electron-probe micro- analysis can sometimes differentiate between stained and unstained areas. Otherwise, the problem is very difficult unless conditions for reproducing the stain can be found. A wide- spread occurrence of a green stain on pale-coloured gloss paints could not be diagnosed com- pletely until it was found that it could be reproduced by the action of aniline, e.g., from mark- ing inks on textiles, and an oxidising agent, e.g., chlorine from bleach, on the surface of the film, to give aniline green. It is hoped that the future will provide techniques for solving them, but at present it is not clear which techniques they will be. References Many problems in paint analysis are concerned with paint defects. This exposition has demonstrated some of the outstanding problems in paint analysis. 1. O’Neill, L. A., and Falla, N. A. R., Chewy Ind., 1971, 1349. 2. O’Neill, L. A., and Christensen, G., J. Paint Technol., 1975, 47 (601), 46. 3. O’Neill, L. A., and Christensen, G., J . Oil Colour Chem. Ass., 1975, 58 (5), 178.

ISSN:0306-1396    

DOI:10.1039/AD9751200229

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

August, 1975 DISTINGUISHED SERVICE AWARD 235 Si lver M ed a I In 1973, the Council of the SAC, as the Analyti- cal Division of the Chemical Society, introduced an award for the encouragement of young scient- ists working in any field covering the practice and teaching of analytical chemistry. The award, known as the Society for Analytical Chemistry (SAC) Silver Medal, is accompanied by a cash prize and is normally made annually to the candidate who, in the opinion of the Council, has made the greatest contribution and whose work has made the most significant impact in any branch of analytical chemistry.In addition, the future promise of the candidate is taken into consideration. It is intended to make the third award during 1975 in accordance with the rules set out below and to provide an opportunity for the successful candidate to deliver a lecture to the Division on a suitable occasion subsequent to the presentation of the Medal.The rules are as follows- 1. 2. 3. 4. 5. 6. 7. 8. The award of the Silver Medal will normally be considered annually by the Honours Committee, acting on behalf of the Council of the Division, but an award may not be made if it is considered that the work of no candidate reaches the required standard. Candidates must be British subjects of 35 years of age or under in the year in which the award is considered.Evidence of age will be required. The merits of the candidate’s work may be brought to the notice of the Council by any person (being a member of the Analy- tical Division of the Chemical Society) who desires to recommend the candidate by letter addressed to The President, Analytical Division, The Chemical Society, 9/10 Savile Row, London, W1X 1AF.The letter should be accompanied by a short statement on the candidate’s career (date of birth, education and experience, degrees and other qualifications, special awards, etc., with dates, and any other relevant information) and a list of titles of, and references to, papers or other works published by the candidate, independently or jointly.One reprint of each paper (or other work) for which reprints are available should be submitted. The award will be made on an over-all assessment of the candidate’s contri- bution, the impact of his/her work and his/her future promise in any field covered by the principles, teaching and practice of the analytical sciences.No restriction is placed as to where the work is conducted. The Committee assessing the applications shall be at liberty to call any candidate for interview. The successful candidate will receive the sum of A100 in addition to the medal. The decision of the Council shall be final. Any alteration to these Rules shall be subject to the approval of the Council. Recommendations for the award in 1975 should be made to The President, Analytical Division, The Chemical Society, 9/10 Savile Row, London, W1X lAF, by September 30th, 1975.

ISSN:0306-1396    

DOI:10.1039/AD975120235b

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

236 CONFERENCES AND MEETINGS Proc. Analyt. Div. Chem. SOC. Conferences and Meetings Symposium on Maintenance of Water Quality September 9-1 1, 1975, Cambridge This Symposium has been arranged by The Institution of Water Engineers and Scientists in association with The Society for Water Treatment and Examination, and will be held at the University of Cambridge. Nine papers will be presented, including the following: “Control of effluents,” by R.G. Toms; “Raw water quality criteria,” by A. H.August, 1975 CONFERENCES AND MEETINGS 237 Goodman ; and “Raw water monitoring, ” by W. M. Lewis. Further information can be obtained from the Secretary, The Institution of Water Engineers and Scientists, 6-8 Sackville Street, Piccadilly, London , W 1X 1DD. Instruments and Control Systems for the Water Industry September 15-17, 1975, Reading This Conference is to be held by the Water Research Centre at the University of Reading and its purpose is : to report current trends and achievements in the use of instrumentation and control systems; to monitor the quality and quantity of natural waters and water supply; and to monitor the control of water and waste water treatment processes.Twenty-one papers will be presented by authors who have been actively engaged on research in this area and will include contri- butions from overseas. The three Sessions are as follows : “Monitoring Quality and Quantity of Surface and Ground Waters”; “Instru- mentation and Automation in Resource Management, Water Treatments and Distri- bution” ; and “Instrumentation and Control in Waste Water Treatment.” In addition there will be a Plenary Session and an Informal Workshop and Exhibition of Equipment.Further information can be obtained from The Conference Organiser, Water Research Centre, P.O. Box 16, Medmenham, Marlow, Bucks., SL7 2HD. First Conference on X-ray Powder Difkaction September 15-19, 1975, Durham This Conference will be held a t the University of Durham and is organised, in conjunction with the Department of Geology of that Univer- sity, by Philips Analytical Department of Pye Unicam Ltd. The aim of the Conference is to widen the scope and acceptability of the technique, with particular emphasis on applications and results.The following topics will be covered : Principles of X-ray Powder Diffraction ; Quantitative Phase Analysis ; Quantitative Analysis ; Instru- mentation and Safety; Texture ; Stress ; Crystal- lite Size and Crystallinity; and Automatic Powder Diffractometry. Further information can be obtained from Mrs.E. Gammon, Philips Analytical Depart- ment, Pye Unicam Ltd., York Street, Cam- bridge, CBl 2PX. Techniques for the Microbiological Ex- amination of Foods, Pharmaceuticals and Cosmetic Products October 7-9, 1975, London About 20 papers will be presented at this International Symposium, which is intended to encourage bacteriologists to compare the techniques they use with those employed by others in the field of microbiology.Further information from J. J. Peake, Scientific Symposia Ltd., 121 King Street, London, W6 9JG.Seminar on Applications of Instrumental Techniques of Analysis October 8, 1975, Stoke Poges Fulmer Research Institute, in association with Thames Polytechnic, is planning to hold a seminar in which some of the modem instru- mental techniques will be described, with particular reference to the ways in which they can be applied to the solution of industrial problems. Case histories will be presented to illustrate these applications, and there will be opportunities for delegates to discuss their own problems with experts in the various techniques, which will include infrared spectroscopy, differ- ential thermal analysis, differential scanning calorimetry, thermogravimetric analysis, thermomechanical analysis , liquid chromato- graphy and gel-permeation chromatography.Further details from Miss K. M. Hutton, Information and Marketing, Fulmer Research Institute, Stoke Poges, Slough, SL2 4QD. Water Quality Control-The Role of Analytical Chemistry October 30, 1975, London This Symposium will be held at Thames Poly- technic, and the topics covered will include automatic and on-line analysis, continuous and harmonised monitoring, oil-pollution analysis , aquatic pollution by heavy metals and inter- national aspects of water pollution.Further details can be obtained from Mrs. S. Taylor, Room 183A, Thames Polytechnic, Wellington Street, London, SElS 6PF.238 CHEMICAL SOCIETY LIBRARY Proc. Analyt. Div. Chem. SOC. Air Pollution Measurement and Environ- ment. Anyone desiring exhibition space or mental Control information regarding the Exposition should October 26-31, 1975, Loughborough address inquiries to Harold Sweeney, Exhibition Chairman, Koppers Company Inc., 440 College Further information about this course can be obtained from Mrs. Sonia Withers, Centre for Extension Studies, University of Technology, Loughborough, Leicestershire, LE 11 3TU.Park Drive, Monroevik Pa. 15146, USA. Symposium on Measurement of Particulate Pollutants in Gas Streams December 3, 1975, Bradford This Symposium, organised by the Yorkshire Section of the Society of Chemical Industry, will be held at The University of Bradford.Lectures will give an up-to-date review of sampling, characterisation and continuous auto- matic measurement of dust in flowing gases together with the related legislation. Further details can be obtained from the Symposium Organiser : Dr.L. Svarovsky, School of Powder Technology, University of Bradford, Bradford, West Yorkshire, BD7 IDP. 27th Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy March 1-5, 1976, Cleveland, Ohio, USA This Conference will be held at the Cleveland Convention Center, Cleveland, Ohio and papers will be presented on new methods and on methods that assist the practising chemist in the solution of everyday problems.Symposia have been organised on subjects which include the following : Gas Chromato- graphy ; Toxicology ; Future Trends in Clinical Chemistry ; Liquid Chromatography ; Criteria for Method Selection in Pharmaceutical Analysis; Recent Advances in Analysis in the Steel Industry in Foreign Countries and in the USA; Coatings in Food and Beverage Can Industry; New Trends in Powder Diffracto- metry; and Energy Dispersive Sources and Systems (ASTM E-2). General papers are not restricted to the symposia topics and it is expected that more than 400 submitted papers will cover many aspects of Analytical Chemistry and Spectro- scopy. Intending contributors should send three copies of a 300-word abstract to Dan P. Manka, Program Chairman 1976, Jones and Laughlin Steel Corporation, Graham Research Labora- tory, 900 Agnew Road, Pittsburgh, Pa. 15230, USA, by September 15th, 1975. As in the past, the Conference will be the site of an Exposition of Modern Laboiatory Equip-

ISSN:0306-1396    

DOI:10.1039/AD975120236c

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

238 CHEMICAL SOCIETY LIBRARY Proc. Analyt. Div. Chem. SOC. Chemical Society Library The following publications of analytical interest have been added to the Library since the last list appeared in Proceedings (1975, 12, 130). Official Methods of Analysis of the Associa- tion of Official Analytical Chemists. Twelfth Edition. Edited by William Honvitz. Association of Official Analytical Chemists. 1975.NMR Spectra of Simple Heterocycles. T. J. Batterham. John Wiley & Sons. 1973. Isolation and Identification of Drugs in Pharmaceuticals, Body Fluids and Post- mortem Material. Volume 2. Edited by E. G. C. Clarke. Pharmaceutical Press. 1975. 17th Colloquium Spectroscopicum Inter - nationale, Firenze, 1973. Preprints of Papers. Three volumes. Hilger. Chemical Analysis of Organometallic Com- pounds.Volumes 2 and 3. T. R. Crompton. Academic Press. 1974. Automatic Chemical Analysis. J. K. Foreman and P. B. Stockwell. Ellis Horwood. 1975.August, 19 75 PUBLICATIONS RECEIVED Af€inity Chromatography. C. R. Lowe and P. D. G. Dean. Sons. 1974. John Wiley & The Particle Atlas: An Encyclopedia of Techniques for Small Particle Identifica- tion.Volumes 1, 2 and 3. Second Edition. W. C . McCrone and J. G. Delly. Ann Arbor Science. 1973. Laser Micro-spectrochemical Analysis. H. Moenke and L. Moenke-Blankenburg. Hilger. 1973. Colorimetric and Fluorimetric Analysis of Organic Compounds and Drugs. M. Pesez and J . Bartos. Marcel Dekker. 1974. Chromatographic Methods. Third Edition. R. Stock and C. B. F. Rice. Chapman and Hall. 1974. Liquid Scintillation Counting. Volume 3. Proceedings of a Symposium on Liquid Scintilla- tion Counting organised by the Society for Analytical Chemistry, Brighton, 1973. Edited by M. A. Crook and P. Johnson. Heyden. 1974. Instrumental Methods of Analysis. Fifth Edition. H. H. Willard et al. Van Nostrand. 1974. The Chemical Analysis of Water. General Principles and Techniques. Analytical Sciences Monograph No. 2. A. L. Wilson. Society for Analytical Chemistry. 1974. 239

ISSN:0306-1396    

DOI:10.1039/AD975120238b

出版商:RSC    

年代:1975

数据来源: RSC

摘要:

August, 19 75 PUBLICATIONS RECEIVED 239 Publications Received Electron Microprobe Analysis. S. J. B. Reed. Pp. xvi + 400. London, ATew York and Melbourne : Cambridge University Press. 1975. Price 412; $34.50. Actualitbs de Chimie Analytique. Organ- ique, Pharmaceutique et Bromatologique. 23e SQi e. l3dite.d by J.-A. Gautier, P. Malangeau and F. Pellerin. Pp. iv + 241. Paris: Masson et Cie. 1975.Price 150F. Principles and Techniques of Electron Microscopy. Biological Applications. Edited by M. A. Hayat. Volume 5. Pp. xx + 250. New York, Cincinnati, Toronto, London and Melbourne : Van Nostrand Reinhold Com- pany. 1975. Price 49-95. Particle Size Measurement. Second Edition. Terence Allen. Powder Technology Series. Pp. xviii + 454. London: Chapman and Hall Ltd. 1975. Price k8.50. The Interpretation of Infrared Spectra-A Programmed Introduction. R. R. Hill and D. A. E. Rendell. Pp. xii + 196. London, New York and Rheine: Heyden & Son Ltd. 1975. Price k4.40; $12; DM36. More Spectroscopic Problems in Organic Chemistry. Second Edition. A. J. Baker, with the collaboration of T. Cairns, G. Eglinton and F. J. Preston. Pp. x + 129. London, New York and Rheine: Heyden & Son Ltd. 1975. Price 42-50; $6.90; DM20-50.

ISSN:0306-1396    

DOI:10.1039/AD9751200239

出版商:RSC    

年代:1975

数据来源: RSC