摘要:

Proceedings of the Society for Analytical Chemistry CONTENTS Reports of Meetings . . .. 163 “Automatic Analysis” . . . . 165 “Thermal Analysis” . . .. 167 Membershjp changes . . ... 172 Papers accepted for The Analyst 172 Publications Received . . .. 173 Notice . . .. . . *. 174 Forthcoming Meetings Back cover Proc. SOC. Anal. Chem. Voi. 2 No. II Pages 163-174 ovember 1965 Vol. 2 No. I I PROCEEDINGS OF November I965 THE SOCIETY FOR ANALYTICAL CHEMISTRY President of the Society A. A. Smales O.B.E. Hon. Secretory of the Society S . A. Price Hon. Treasurer of the Society D. T. Lewis C.B. Hon. Assistant Secretaries of the Society B. S . Cooper; D. W. Wilson Secretary Miss P. E. Hutchinson 14 BELGRAVE SQUARE LONDON S.W.1 Telephone BELgravia 3258 Editor J. B. A t t r i i l Proceedings i s published by The Society for Analytical Chemistry and distributed to members and all subscribers to The Anaryst without charge Single copies may be obtained direct from the Secretary The Society for Analytical Chemistry.a t the above address (NOT through Trade Agents) price 2s. 6d. post free. Remittances payable to “Society for Analytical Chemistry” MUST accompany orders Official Standardised and Recommended Methods of Analysis Compiled and Edited for THE ANALYTICAL METHODS COMMITTEE OF THE. SOCIETY FOR ANALYTICAL CHEMISTRY by S. C. JOLLY B.Pharm. BSc. A.R.I.C. M.P.S. PP* x*+577 Price 5% 6s. net Members of the Society for Analytical Chemistry are entitled to buy copies a t the special Members’ price of i 4 4s. provided they order direct from The Editor The AnaZyst 14 Belgrave Square London S.W.I. Remittances made out to “Society for Analytical Chemistry” must accompany Members’ orders. Published for the Society for Analytical Chemistry W. HEFFER & SONS LTD. PETTY CURY CAMBRIDGE bY

ISSN:0037-9697    

DOI:10.1039/SA96502FX039

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

THE SOCIETY FOR AXALYTICAL CHEMISTRY Forthcoming Meetings-continzted December Thursday 9th I,oNDON Friday 10th BIRMINGHAM Friday 10th l,ON DON Monday 13th RRISTOL Thursday 16th LONDON Friday 17th CAR 11 IFF BIOLOGICAL METHODS GROUP Annual General Meeting followed by a Dis- Discussion on “Problems and Dilemmas in Microbiological Assay,” to be “The Feathers,” Tudor Street London E.C.4; 6.30 p.m. MIDLANIE SECTION jointly with the Chemical Society. cussion Meeting. opened by S. A. Price R.Sc. F.R.I.C. “The Partition of Mixtures of Homologues and Isomers by Chromato-polarography ” by Professor W. Kemula. Haworth I xcture Thcatrc Chemistry Department The University Birm- ingham 15; 5.30 p.m. MICROCHEMICAL M1mioiI)S GROUP Annual General Meeting. “A Statistical Approach to Analysis,” by A. K.Soper M.Sc. F.R.I.C. Meeting Room of the Chemical Society Burlington House Piccadilly London \V. 1 ; 6.45 p.m. WESTERN Siccriolil jointly with the Chemical Society and the Rristol Sections o€ the Royal Institute of Chemistry and the Society of Chemical Industry. “‘l~he Partition oC Mixtures of Homologues and Isomers by Chromato- polarography,” by Professor W. Kcmula. School of Chemistry The IJni versity Bristol ; 5.30 p.m. SOCIETY jointly with thc Chemical Society. “The Partition of Mixtures of Homologues and Isomers by Chromato- polarography,” by Professor W. Kemula. School of Pharmacy 29 Brunswiclc Square London W.C.l; 6 p.m. “Atomic-absorption Spectrophotornetry,” by H. Pugh M.Sc. A.R.I.C. Cardiff; 7 p.m. WESTERN SECTION. The Determination of Sterols Society for Analytical Chemistry Monograph No.2 -0- This Monograph contains six papers on various aspects of the determination of sterols by colorimetric and chromato- graphic methods applicable in many fields -0- Available ONLY from The Editor “The Analyst,” 14 Belgrave Square London S.W. I (Not through Trade Agents) Price 15s. or U.S. $2.00 Post free A remittance made out to “Society for Analytical Chemistry” should accompany every order. Members of the Society may purchase copies at the special price of 5s.. post free. THE SOCIETY FOR ANALYTICAL CHEMISTRY Forthcoming Meetings November Tuesday 23rd LONDON Wednesday 24th LONDON Friday 26th GLASGOW Tuesday 30th LONDON December Wednesday 1 st LONDON Thursday 2nd LONDON Thursday 2nd GLASGOW Friday 3rd GLASGOW Saturday 4th LIVERPOOL Tuesday 7th BIRMINGHAM SPECIAL TECHNIQTJES GROCJP Annual General Meeting followed by the Address of the Retiring Chairman Ur.L. Brealey B.Sc. F.R.I.C. on “Some Analytical Problems in the Power Generating Industry.” Meeting Room of the Chemical Society Burlington House Piccadilly London MICROCHEMICAL METHODS GROUP Discussion Meeting. Discussion on “The Optimal Environment for Microchemical Analysis” “The Feathers,” Tudor Street London E.C.4; 6.30 p.m. SCOTTISH SECTION. “Separate or Calculate,” by A. L. Glenn B.Sc. B.Pharm. Ph.D. F.P.S. University of Strathclyde Glasgow ; 5.30 p.m. ATOMIC-ABSORPTION SPECTROSCOPY GROUP Annual General Meeting. “Atomic-fluorescence Spectroscopy,” by G. I. Goodfellow. Meeting Room of the Chemical Society Burlington House Piccadilly Idondon w.l; 7 p.m. will be opened by A.J. Cross B.Sc. w.l. THIN-LAYER CHROMATOGRAPHY GROUP Annual General Meeting. “A Study of the Oxidation of Nitrosoaromatics to Nitroaromatics in Propellant Stabilisers IJsing Thin-layer Chromatography and Mass Spectrometry,” by J . W. Grindlay P. M. Wraighte and J . C. Wright. “The lletermination of Antioxidants and Other Additives in Mastics by Thin-layer Chromatography,” by G. R. Campbell. “Study of the Auto-oxidation of Lanosterol by Thin-layer Chromatography,” by J . Scotney. Chelsea College of Science and Technology Manresa Road London S. W. 3; 2.15 p.m. THERMAL ANALYSIS GROUP Annual General Meeting. “Coal Carbonisation Kinetics--Simple Thoughts on a Corn plex Matter,” by I>. Fitzgerald M.A. B.Sc. Ph.U. M.1nst.F. “‘The Analysis of Volatile Materials by Mass-Detection Gas Chromatography,” by S.C. Bevan B.Sc. Ph.D. F.R.T.C. and S. Thorburn B.Sc. Ilip.Ed. F.R.I.C. Meeting Room of the Chemical Society Burlington House London W.l; 6.30 p.m. SCOTTISH SECTION. Ramsay Dinner. Central Hotel Glasgow; 6.30 p.m. Scorrrsw Sfl:c’rIoRr joixtly with the Local Sections of the Chemical Society the “Chemistry for Profit,” by J. W. Ihrrett 13.Sc. Ph.l>. A.fi.C.S. L).L.C. liniversity of Strathclyde (;lasgow ; 6 p.m. NonTw OF ENGLAND SICCTXON Ordinary Meeting on “The Training o f the Speakers A. G. Jones U.Sc. F.l<.I.C. and H. It. Jones B.Sc. F.K.T.C. Lecture Theatre City Laboratories Mount Pleasant Liverpool ; 2.38 p.m. MIDLANDS SIXTION jointly with the Guild of Associates of the University of Speakers F. C. Rroughall B.Sc. F.R.I.C. S. €3. Jenkins 13.Sc. F.R.I.C. 13yng Kenrick Suite University of Aston (Designate) Birmingham; 7 p.m. Society of Chemical Industry and the Royal Institute of Chemistry. h.M.I.Chem.E. F.lZ.1.C. Analyst in Physical Methods.” Aston (Designate) Discussion Meeting on “EfRuent Analysis.” F.Inst.S.I-’. and N. ‘r. Wilkinson 1;. R.I.C. * l’lease note that this is a change of place from that originally announced. Continued inside back cover PRINTED BY W. HEFFER & SONS LTD. CAMBRIDGE. ENGLAND.

ISSN:0037-9697    

DOI:10.1039/SA96502BX041

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

November 1965 PROCEEDINGS OF THE SOCIETY Vol. 2 No. I I FOR ANALYTICAL CHEMISTRY Regional Development of the Society IF the Society is to remain a vital organisation it must be ever ready to expand its scope to reshape its structure and to revise its activities in keeping with the marchof analytical chemistry and with the needs and interests of its members. This does not mean the adoption of a new policy twenty years ago the Society introduced subject Groups a radical change of structure; ten years later it relinquished the name it had held since its formation eighty years earlier; in I959 it made material changes in its Memorandum of Association; and less than two years ago it replanned and rebuilt its Group and Panel structure. It now plans to take another forward step by modifying its Section structure in the direction of a revised geographical aggregation.The Report of a special Committee that reviewed in depth the existing Section structure recommended the formation of two new Sections a step that would give a more realistic structure and it is hoped would increase the Society’s dynamic centres of activity. One of the existing Sections involved in the changes is the Midlands Section. Communications between East Anglia and the central part of the Section are very difficult and it is likely that membership of the Society in the former area will increase as industry expands. The Committee’s recommendation was that the Midlands Section should be divided into two Sections by a north-south line through Peterborough the area to the east being an East Anglian Section and the area to the west to continue as the Midlands Section.The other recommended change in Section structure involves the North of England Section which covers a particularly large area and traditionally conducts its main Society activities in the Liverpool - Manchester area. The large concentration of chemists in the North East area and the difficulty of communications with the southern and western parts of the present Section were pointers to the need to create another Section and the Committee recommended that the area east of the Pennine ridge and north of and including Northallerton should constitute a North East Section. The remainder of the existing Section should be re-defined to include Stoke-on-Trent. The Committee’s recommendation created yet another occasion when a step forward involved breaking links with the past.Tradition is a just source of pride but if revered in the extreme it can become a shackle that hinders progress. And the alternative to progress is stagnation. It speaks well for the spirit of the Society that when the proposed changes came before Council on which the Sections to be divided are represented they were adopted unanimously. In the proposed revision of its Section structure the Society has an opportunity of taking yet another step forward in modernisation and energisation. Rut the opportunity will be lost unless the plans are put into practice. The history of the Society abounds in the names of members who have given greatly of time and thought to its administration men for whom long services in office on committees or on Council have been labours of love and there is ample evidence that there is no lack of them in the Society today.Some of them are in East Anglia and there are others in the North East and from them the President asks for volunteers for the duties involved in organising guiding and administering a new Section. It is his hope that he will receive personally from members in those areas offers of active support that will guarantee the successful launching and future of an East Anglian and a North East Section. Surely this can be done? The Section Structure Committee stated in its Report- “In making these recommendations to Council it is realised that the changes envisaged will be meaningless unless a nucleus of members can be found in the areas covered by the new Sections who have sufficient initiative and enthusiasm to get the Sections organised. Thus these recommendations offer a challenge to our members. . . .” The challenge has now been issued-and the President and Council believe that members in East Anglia and the North East will not be found wanting. A. J. A. 163

ISSN:0037-9697    

DOI:10.1039/SA9650200163

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

164 REPORTS OF MEETINGS [Proc. SOG. Apzal. t‘dzem. Reports of Meetings NORTH OF ENGLAND SECTION AN Ordinary Meeting of the Section was held at 2.30 p.m. on Saturday October Znd 1965 at the City Laboratories Mount Pleasant Liverpool. The Chair was taken by the Chairman of the Section Mr. J. F. Clark MSc. A.R.C.S. D.I.C. F.R.I.C. F.R.S.H. The following paper was presented and discussed “The Analysis of Feeding Stuffs and Fertilisers,” by A. G. Roach BSc. Ph.D. A.R.I.C. WESTERN SECTION AND MICROCHEMICAL METHODS GROUP A JOINT Meeting of the Western Section and the Microchemical Methods Group was held on Friday and Saturday September 24th and 25th 1965 at the University of Exeter. The subject of the meeting was “Trace Analysis.” At the scientific session on Friday the Chair was taken by the Chairman of the Micro- chemical Methods Group Mr.R. Goulden F.R.I.C. and the following papers were presented and discussed “The Determination of Micro-constituents of Sea Water,” by F. A. J. Arm- strong F.R.I.C. ; “The Use of the Stationary Mercury-drop Electrode for Trace Analysis,” by J. F. C. Tyler R.Sc. Ph.D. F.R.I.C. ; “The Sub-nanogram Region,’> by E. Bishop K.Sc. A.R.C.S.T. F.R.I.C. The Chair at the scientific session on Saturday was taken by the Vice-chairman of the Western Section Dr. L. E. Coles B.Pharm. F.P.S. F.R.I.C. and the following papers were presented and discussed “The Determination of Trace Contaminants in Peroxygen Compounds,” by C. Whalley B.Sc. F.R.I.C. and D. B. Adams M.A. BSc. A.K.I.C. ; “The Determination of Some Impurities in Beryllium by Differential Cathode-ray Polaro- graphy,” by G.D. Goode B.Sc. A.R.I.C. and J. Herrington K.Sc.; “The Application of Some Ternary Complexes in Trace Analysis,” by R. M. Dagnall M.Sc. Ph.D. On Saturday evening there was a Discussion Meeting at which the Chair was taken by the Chairman of the Microchemical Methods Group Mr. K. Goulden F.R.I.C. After a talk on “Current Work on Biophysics and Radioactive-tracer ‘Techniques in use at the Marine Biological Station,” by J. Bryant Ph.D. a discussion on “Trace Analysis in Aqueous Media” was opened by L. H. N. Cooper Ph.D. DSc. F.G.S. F.K.I.C. F.I.Kiol. F.K.S. The meeting also included a guided tour of the new Chemistry Laboratories of Eketer University and a visit to the Marine Biological Station Plymouth. WESTERN SECTION AN Ordinary Meeting of the Section was held at 6.30 p.m.on I;riday October 8th 1965 in the Welsh College of Advanced Technology Cathays Park Cardiff. The Chair was taken by the Chairman of the Section Mr. E. A. Hontoir R.Sc. A.I.M. ’The following paper was presented and discussed “The Chemist in Forensic Science,” by C. F. Tippett M.A. MIDLANDS SECTION AND SPECIAL TECHNIQUES GROUP A .JOINT Meeting of the Midlands Section and the Special Techniques Group with the Kr- mingham and Midlands Section of the Royal Institute of Chemistry and of the Societv of Chemical Industry was held at 6.30 p.m. on Thursday September Wth 19635 in the Haworth Lecture Theatre The University Edgbaston Birmingham 15. The Chair was taken by the Chairman of the Birmingham and Midlands Section of the Society of Chemical Industry Professor W.G. S. Parker B.Sc. Ph.D. A.F.R.Ae.S. F.K.I.C. The following paper was presented and discussed “Some New Principles in NeLItron- activation and Isotope-dilution Analysis,” by J. RfiiiEka C.Sc. and J. Star? 11.S~. MIDLANDS SECTIOX A JOINT Meeting of the Midlands Section with the Cambridge Sub-section of the Koyal Institute of Chemistry was held at 7.46 p,m. on Thursday October 14th 1965 at the Cam- bridgeshire College of Arts and Technology Cambridge. The Chair was taken during the presentation of the papers by the Chairman of the Cambridge Sub-section of the Royal Institute of Chemistry Mr. C. F. Hadley M.A. A.K.I.C. and during the discussion ?)J the Vice-chairman of the Midlands Section Mr. H. E. Rrookes E.Sc. F.1C.I.C. November 19651 AUTOMATIC ANALYSIS 165 The following papers were presented and discussed “The Analysis of Pesticide Residues,” by I<. E. Elgar H.Sc. A.R.I.C. ; “The Positive Identification of Pesiticide Residues,” by K. I. Beynon I<.Sc. Ph.D. THIN-LAYER CHROI1IATOGIIAPHY GROUP An Ordinary Meeting of the Group was held at 7.15 p.m. on Wednesday September 29th I R M in the Department of Textile Industries The University Leeds. The Chair was taken by the Chairman of the Group Dr. E. V. Truter BSc. A.R.C.S. ’The following papers were presented and discussed “Thin-layer Chromatographic Study oi the Reactions of Adsorbed Molecules,” by I?. Williams A.K.I.C. ; “Thin-layer Chroniatography of Aminoacids,” by I?. F. Lofts B.Sc.

ISSN:0037-9697    

DOI:10.1039/SA9650200164

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

November 19651 AUTOMATIC ANALYSIS 165 Automatic Analysis The following is a summary of one of the papers presented at a Joint Meeting of the Mid- lands Section with the Lea Valley Subsection of the London Section of the Royal Institute of Cliernistry held on April 21st 1965 and reported in the June issue of Proceedings p. 83. Methods in Automatic Analysis By G. MATTOCK AND A. UIGGENS (Eflietvtt Contvol Ltd. Ceovge St. Wolverhavnpton and Electvonic Industvies Lfd. Lowev MoPtZake Road Richnzond Suvvep) DR. MATTOCK said that there were three essential features of an automatic analyser sample handling standardisation and determination with the important addendum of utilisation of results. Sa?iifjle and Reageat Ha.tzdli.tzg Two general cases were considered in which (1) a quantity of sample was treated with a given amount of reagent (or reagents) to give a system that was directly measurable by some physical technique (e.g.colorimetric potentiometric or voltammetric) or (2) a given amount of sample was treated with reagent (or reagents) to a certain fixed condition and the amounts of the reagents measured to provide the analytical information (e.g. titrations of various kin (1 s) . In both approaches the problem of metering arose but to various degrees of difficulty. Thus with a system involving a fixed ratio of sample to reagents only the ratio needed to be held constant to maintain analytical accuracy e.g. with one incorporating peristaltic pumps. Where a variable amount of reagent was to be added to a fixed volume of sample it was usually easier to use batch methods rather than continuous ones.The sample could be dispensed from automatic pipettes or from a precise metering pump while the amount of reagent required to reach the desired analytical condition could be measured optically electrically or mechanically (through a metering-pump counter) as a volume of solution or coul omet rically . ISatch methods also came into their own when a sequence of operations was to be per- forrncid on a given sample to give more than one analytical result or where results were only required at fairly infrequent intervals. Awto~natic Standardisatiovt ,%utomatic standardisation should be considered a pre-requisite for an autoiiiatic analyser although few pieces of equipment did in fact incorporate the facility. It was usually accom- plished by arranging for a standard as similar as possible in composition to the sample to be available and incorporating in the analyser a timer or other controlling device to introduce the standard instead of a sample at periodic intervals.An automatic re-setting operation was then carried out to compensate for any drifts that might have occurred. 166 AUTOMATIC ANALYSIS [Proc. Soc. Anal. Client. Exam@ Determination Methods Not all analytical procedures were conveniently applicable to automatic equipment e.g. gravimetric operations. Instrumental methods e.g. titration potentiometric colorimetric and voltammetric measurements on the other hand were usually readily applicable. The classic example of titration considered was the acid - base or redox titration where the amount of titrant required to achieve a poised condition was measured.Commercial instruments were available that operated on the batch principle measuring the volume of reagent required either from a burette or from a metering pump. Continuous systems were also available where feedback control varied the pumping rate to maintain a constant titration end-point condition the rate being directly proportional to the concentration of the flowing sample. Coulometric reagent generation was an attractive alternative to volunaetric systems. For potentiometric measurement a distinction could be made between a common poteiztio- metric measurement (e.g. of pH) and the application of such a measurement where some sample pre-treatment was required. Continuous or batch equipment for this operation was commercially available and had been applied to automatic determination of chloride and to automatic determination of cyanide both with a silver - calomel electrode pair and to sodium in natural waters with a sodium ion - responsive glass - calomel electrode pair.In colorimetric measurement the sample handling and automatic standardisation princi- ples were applied on a basis of a fixed reagent - sample ratio to produce a solution suitable for the measurements of colour density. Two important examples were in the automatic determination of silica and of fluoride. Chief interest in voltammetric measurement had centred on the determination of dis- solved oxygen (particularly with the Mackereth electrode) but other applications e.g. determination of trace metals in effluents have also been investigated. A Pfllication of A ytalytical Results Although an automatic analyser did not intrinsically provide more than analytical results consideration had to be given to their utilisation.It was not really appropriate to use the equipment simply as a monitor in industrial plants even as a preliminary to closed- loop control. Monitoring over a wide range required relatively complex and expensive instruments whereas direct application into closed-loop control permitted the designer to concentrate on a narrow band corresponding to one analytical condition which resulted in production of a cheaper and simpler instrument. Some examples of closed-loop control were in the determination of acid in spin-bath liquors (pH titration) of alkali in synthetic detergents (pH titration) of chloride in make-up water (potentiometric measurement) and of silica in boiler feed water and in water treatment (colorimetric measurement). Dr. Mattock then referred to the approximate costs of representative commercial equip- ment which were important for assessment of potential value. A typical titrator cost about k1,750; the cyanide and chloride monitors mentioned above were about FlOOO each; while one commercial silica analyser cost L1300 including automatic self-standardisation but excluding an industrial cabinet. Consideration should also be given to reagent costs (which could have a bearing on the choice between continuous and batch instruments) and to the level of skill required for maintenance and these should be compared with the advantages (when closed-loop control was applied) of a more closely controlled product.

ISSN:0037-9697    

DOI:10.1039/SA9650200165

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

November 1 9651 THERMAL ANALYSIS 167 Thermal Analysis The following are summaries of papers presented at the Inaugural Meeting of the Thermal Analysis Group held on May 28th 1965 and reported in the July 1965 issue of Proceediutgs (p. 104). Differential Thermal Analysis and Therrnogravimetric Analysis Studies at Salford on Metal Oxy-salts Coals and Polymers BY D. DOT,LIMORE (The Hoyal College of A dvaw,ced TecJmology Salfovd LancasJaive) DR. DOLLIMOIIE said that the physico-chemical changes to be noted on heat treatment 01 materials included those of surface area density and strength of powder compacts. To make a full correlation it was usually necessary to use thermogravimetric analysis to provide details of the isothermal decomposition and then to establish the kinetics of decomposition.Differential thermal analysis gave indication of enthalphy changes separated over lapping decompositions and indicated the existence of phase transformations. The equipment employed at Salford had enabled these studies to be made in different gas atmospheres in dynamic or static systems at different pressures or iut 'uaczzo. The changes taking place in samples could also be confirmed by chemical analysis or X-ray diffraction. Thermogravimetric analysis 'was carried out on a variety of instruments such as the commercially available equipment from Stanton Webb and Cahn or the laboratory-con- structed apparatus such as that described by Gregg with subsequent modifications by other workers. Dr. Dollimore went on to say that the usual pattern of experiments that had been adopted for kinetic studies involved the determination of the rate of weight change while the sample was heated isothermally over a range of temperatures.Wide use was also made of apparatus which recorded pressure changes while the sample was being heated. On occasions when there were no pressure changes e.g. when the sample was heated under vacuum with continuous pumping the weight change was then measured and invariably recorded as the fraction of material decomposed versus time. It sl-iould be remembered that as the reaction was heterogeneous it was not expected that the same kinetic mechanism would describe the entire reaction. Differential thermal analysis was carried out on a Netsch or similar apparatus in which the atmosphere could be controlled. The equipment should be capable of recording AT the temperature of the inert reference material and the evolution of gaseous products enabling distinction to be made between phase changes and chemical reactions.X-ray diffraction data density and the low-temperature nitrogen adsorption isotherm were other parameters which aided the study of physico-chemical changes accompanying thermal decomposition. The systems studied at Salford included the decomposition of oxysalts especially oxalates the carbonisation of polymers and various lieat treatments of coal. With oxalates and oxysalts of metals of variable valency e.g. manganese a variety of oxides might result on thermal decomposition and the free-cnergy data might best be repre- sented in terms of dissociation pressure. The situation revealed by thermogravimetric analysis was that the following transition temperatures existed between the manganese oxides- but this varied somewliat according to circumstances.Free energy for the reaction- 2Mn0 -+ Mn,O + $0 could be expressed as a function of temperature and from this a dissociation pressure equation could be derived which indicated that the dissociation pressure reached the partial pressure of oxygen in the atmosphere a t 448" C. This was in reasonable agreement with the experi- mentally observed value of 550" C for the conversion- MnO -+ Mn,O, 168 THERMAL ANALYSIS [Proc. SOC. AmaE. Chem. A similar treatment for the conversion- 3Mn20 -+ 2Mn30 -# +02 indicated a conversion temperature of 1127' C. This was higher than the recorded tempera- ture of 950" C but could have arisen from an a +? transformation which was not reflected in the free-energy data.Differential thermal analysis results confirmed the above observa- tions but in this instance the a -+ y transformation had proved difficult to detect. The presence of copper made the change- Mn20 -+ Mn,O reversible and this was of importance in considering the mechanism of catalysis in which binary oxides of manganese and copper were used in the oxidation of carbon monoxide. The isothermal decomposition of manganese oxalate and carbonate had been studied in some detail and the first-order decay law only held over less than the last 10 per cent. of the reaction ; this illustrated the cautionary attitude that had to be exercised in attempting the evaluation of kinetic parameters from thermogravimetric analysis curves. Thermogravi- metric and differential thermal analysis studies on coal systems had revealed two processes occurring in coal on carbonisation in nitrogen uix primary and secondary gasification or carbonisation.In the primary process compounds of carbon hydrogen and oxygen were released while in the secondary process mainly hydrogen was evolved. Differential thermal analysis results showed that the two processes were separate for low-grade coals but those for high-grade coals and anthracite showed no such distinction. In studying the isothermal decomposition of coal in nitrogen typical S-shaped curves were obtained for plots of weight- loss versus time while a plot of surface area versus time always showed a break. It was Dr. Dollimore's assumption that the reduction of surface area was caused during the primary- gasification process and represented the filling of the pores with tarry matter.The reproduc- tion o f the surface area after some time then represented the decomposition of the tarry material. The speaker next outlined several mechanisms that had been formulated for the production of tarry matter. Dr. Dollimore concluded by briefly outlining work on the thermal degradation of pofy- mers in which field differential thermal and thermogravimetric analysis had been used for carbonisation studies in nitrogen. The carbon residues had been further heat-treated with a view to graphitisation. The extent to which this had been achieved was then determined by X-rav diffraction. Two points emerged from this work firstly that in a large number of instances an initial complete endothermic peak overlaped a developing exothermic peak and secondly that in all cases where graphitisation occurred the first decomposition was endo- thermic.Thermal Stability Studies on Polymers By W. W. WRIGHT (Hqyal A ivwaft Establishment Favnbovough flavtzfishive) DTI. WRIGHT pointed out that there was no clear definition or standard of thermal stability or generally acxepted method for its assessment. Clearly the final practical criterion of thermal stability was that a material should maintain its properties o E interest at a certain temperature for a certain time. This might be achieved even if considerable degradation occurred (6.g. the use of polymers under ablative conditions) but on the other hand even a minute change in a material might be sufficient to invalidate its use.For a really basic knowledge of the thermal stability of a polymer information was required of both thci rnechan- ism and kinetics of breakdown. This involved elucidation of the nature c9f the volatile degradation products of the changes in the structure and molecular weight of the residual material and of the rates at which these changes occurred. Such investigations could be very time consuming and most workers in the field in assessing new polymers adopted the rnuch more qualitative approach of tliermogravimetric analy Even with this approach there was a ver diversification in the experimental techniques and in the methods of express- ing or ass he results reported in the literature. It was to be hoped that with the setting up of t)odies such as the Thermal Analysis Group some standardisation would arise in the field.. November 19651 THERMAL AXALYSIS 169 Even with standardisation however it had to be remembered that many factors had a pro- found effect on the stability determined by weight-loss measurements. This pointed to the necessity of characterising the polymer used as completely as possible if valid correlations were to be drawn between chemical structure and thermal stability. The type of apparatus used at the Royal Aircraft Establishment was based on that of Madorsky of the National Bureau of Standards though a fused-quartz spring of sensitivity approximately 400 ,u per mg was employed rather than one made from tungsten wire. No difficulties had been experienced through the use of quartz. The base of the balance housing was also of silica and could be heated to 900" C.The temperature recorded by a thermo- couple within the balance housing could be kept constant within 0.25" C by means of a platinum resistance-thermometer operating in conjunction with a proportional temperature controller. In vacuum large differences between the temperature of the platinum crucible and that of the recording thermocouples could arise even though these were only 1 mm or so apart. These differences which could amount to as much as 30" to 40" C arose because heating was effectively by radiation only. Very careful pre-calibration of the apparatus was necessary to obtain the correct temperature measurement. For work in gaseous atmospheres (normally oxygen or nitrogen) the apparatus incor- porated a glass solenoid pump for continuous circulation of the gas an absorption vessel to remove carbon monoxide carbon dioxide and water and a manometric system to maintain a constant pressure and measure the oxygen uptake when oxygen was used.Pressures in the apparatus were restricted to a maximum of 300 mm of mercury since above this limit con- vection currents in the balance housing set up vibrations in the spring or variations in the temperature of the thermocouple. The sample size was approximately 10 mg all material being brought to constant weight at 100" C and to mm of mercury pressure before examination. With this size of sample the reaction was not significantly controlled by diffusion. These included the profound effect that trace impurities rniglit have on weight-loss results which was illustrated by thermogravimetric-analysis curves for a fluorosilicone free from and containing residual basic catalyst.The effect of configuration of the linkage between aryl groups was demonstrated with thermogravimetric-analysis curves for polyamides derived from 0- m- and fi-phenylene diarnines and phthalyl isophthalyl and terephthalyl chlorides. The $ara-$ara and meta- $ara linked polymers were much more stable thermally. Relative thermal stability plots derived from isothermal data were then shown for various polymer systems. The first gave results for polymers containing fluorine in both vacuum and oxygen. The spread of results showed that the incorporation of large quantities of fluorine in a polymer did not of necessity confer thermal stability. The remainder of the relative thermal stability plots showed results in vacuum for polymers containing aromatic rings in the chain e.g.polyphenylenes and polyphenylene oxides. In general the simple unsubstituted polymers were the most stable substitution in the aromatic nuclei resulting in lower stability and complete breakdown of the polymers over a relatively narrow temperature-range. Linking groups such as -C0- -0- and -SO,- had considerable thermal stabilities. I n conclusion the speaker made a plea for weight-loss studies to be coupled with some analysis of the volatile products. The speaker then detailed some of the results obtained with this apparatus. Thermal Analysis Studies of Phenolic Resin Systems RY 13. 1,. TREHERNE ( TJniveusnl (;Finding Whee2 Co. Lld. Stafford) MR. TREHEKNE said that of the many thermal methods available for studying phenolic resins lie would limit his lecture to describing differential thermal analysis - gas evolution and pyrolysis - gas chromatography.The D.T.A. gas evolution apparatus consisted of a thermistor detector fitted to one elid of the D.T.A. furnace tube. The volatile products were collected in a cold trap and sub- sequently analyscd by gas - liquid chromatography. D.T.A. results on phenolic resins were 170 THERMAL ANALYSIS [PYOC. SOC. Anal. Chem. very variable indeed. Mr. Trelierne commented that he had yet to see two identical published results for the same material. However much useful information could be obtained from such thermograms. For example the curing cycle and the degradation of a fully-cured resin could both be used as methods of quality control and further it was a fairly easy matter to distinguish between novolak and resole resins.The extent of polynierisation using different phenol to formaldehyde ratios and catalyst concentrations had also been studied. Gas evolution studies had not yet been translated into a quantitative basis but with the ther- mistor detector mentioned earlier volatile products such as water and ammonia had been identified together with general degradation products. Difficulties encountered with the D.T.A. gas-evolution technique included coalescence and shrinkage of the sample and different conductivities of the gas atmosphere that caused peak shifting. The pyrolysis unit which was connected directly to a commercial gas chromatograph consisted of an electrically heated NicEirome spoon which attained the required temperature within a few seconds.The pyrolysis - gas chromatography studies had shown over 25 products to be formed on degradation most of which had been identified with dual detectors on the gas chromatograph. Quantitative determination of the individual volatile products bad so far been unsuccessful. In these studies the nature of the phenolic resin caused con- ductivity problems which favoured surface degradation only. li' the temperature rise was rapid a skin was formed on the resin (similar to ablation phenomena) and degradation products formed by a break in this skin leaving the centre of the resin sample virtually unchanged. Mr. Treherne concluded by commenting that in spite of all these difficulties much useful information could be obtained and that this was an exciting field in which to work with plenty of scope for speculation.Thermal Analysis in the Investigation of Naturally-occurring Inorganic and Organic Materials BY R. 13. MITCHELL (The Macaulay lulstitute jov Soil Reseavch Abevdeepz) MR. MITCHELL said that differential thermal analysis had been used in the Department of Pedology of the Macaulay Institute for Soil Research since 1947. During this period con- siderable alterations and refinements had been made to the equipment which had greatly improved the reproducibility of the thermal curves and had enabled the unambiguous cletec- tion of very small heat-energy changes. However the development of controlled-atmosphere techniques had more than any other innovation or refinement served to increase the applica- tion of the method.APPLICATION TO INORGANIC MATERIAIS D.T.A. was used for the rapid mineralogical assay of clays separated from the morpho- logically-diff erentiated horizons of soil profiles and on the basis of the D .T.A. curves samples were selected for further examination by X-ray infrared absorption spectroscopy electron microscopy and chemical methods. Soil clays constituted a continuum from completely disordered through poorly ordered to highly crystalline material but for several years it had been assumed that the clay fraction of soils consisted almost entirely of crystalline clay-rninerals and that inorganic material so poorly ordered as to be amorphous to X-Rays or electrons was present only in small amounts. However with refined thermal methods in conjunction with chemical pretreatments it had been recently demonstrated that many soil clays of the temperate zone contained a high proportion of X-ray amorphous material.Goethite and gibbsite (hydrates of iron oxide and alumina respectively) were commonly occurring accessory minerals in soil clays. 130th of these minerals underwent endothermic reactions in the region of 300" C and frequently occurred in admixture. However again by a combination of chemical and thermal methods each might be satisfactorily identified and determined. Also since the crystalline clay- mineral fraction was usually heterogeneous and the components might exhibit thermal effects within the same temperature range the development of techniques that would render their thermal curves more diagnostic was o f the utmost importance. One such method namely November 19651 THERMAL ANALYSIS 171 the treatment of the clay with 5 per cent.piperidine solution had been investigated in detail and the tracing of the complete-combustion curve of the piperidine - clay complex improved the subjective estimation of the crystalline clay-mineral complement. These examples served to show the value of sample pre-treatment in soil clay studies and it should also be mentioned that in this connection strict attention must also be given to methods of removing organic matter and to the particle size of the sample. It had become increasingly evident that hydroxides of aluminium iron and magnesium might be precipitated during pedogenic weathering in the interlayer space of layer-lattice minerals leading to the formation of intergradient minerals showing some of the features of chlorite.Mr. Mitchell said that aluminium-interlayered clay minerals had been synthesized in his laboratory and that their thermal curves exhibited endothermic peaks at about 250" C thought to be associated with the dehydroxylation of the alumina coating the clay-mineral surface and at 450" C reflecting the dehydroxylation of alumina fixed in the interlayer space. From D.T.A. evidence the former might be removed by treatment with 5 per cent. sodium carbonate solution but one or more digestions with sodium citrate were required to remove the int erlay er material . Phosphates were of considerable importance in soils and while it was seldom possible to detect their presence by thermal methods the differential thermal and thermogravimetric characteristics of a number of synthetic and naturally-occurring acid neutral and basic phosphate hydrates had been determined.The dehydration features of these compounds might be followed readily by thermal techniques; size and peak temperatures of the energy changes were related to particle size and degree of crystallinity. Although gypsum and carbonate were seldom present in Scottish soils they were fre- quently encountered in the soils examined from the warmer overseas territories. Gypsum was identified by D.T.A. from the 2 dehydration peaks at 150" C and 170" C and it was possible to detect as little as 1 per cent. of this mineral even in a soil clay containing a large amount of absorbed water e.g. a montmorillonitic clay. Carbonate was usually present in soil in the form of either calcite or dolomite and D.T.A.was also used for the rapid assay of these minerals. Calcite gave a large single endothermic peak at about 850" C whereas dolomite gave 2 endothermic effects a subsidiary in the region of 780" C and a principal peak a t about 850" C. The peak at 780" C resulted from a lattice rearrangement and the rate was determined by the diffusion processes in the solid state. Calcite was formed and determin- ation by this reaction in an atmosphere of carbon dioxide did not therefore affect the peak temperature whereas the calcite decomposition peak was elevated to 925" C. For the lxnambiguous detection of these minerals it was generally considered desirable to deter- mine their thermal curves in both nitrogen and carbon dioxide atmospheres. Such a procedure was however not infallible since sodium chloride decomposed within the temperature range of the first dolomite peak and consequently a soil clay containing sodium chloride and calcite gave a high-temperature pattern similar to that of dolomite.APPLICATION TO ORGANIC MATERIALS The introduction of controlled-atmosphere techniques to D.T.A. and T.G.A. had been responsible for the recent wide application of the method to organic materials. I t was normal practice to examine naturally-occurring organic materials in either an oxidising atmosphere which enabled the complete cornbustion characteristics to be elucidated or in an inert atmosphere which permitted the assessment of the low-boiling volatile content and also indicated the energy required to initiate the principal decomposition reactions.Thermal techniques were used for the characterisation of the morphologically distinct zones of peat profiles and D.T.A. had also been applied to an exploratory investigation of fresh plant materials including the leaves of higher plants pollen lower plants such as ferns mosses algae fungi and yeasts and a range of reference organic chemical compounds. Tenta- tive interpretations of the curves in terms of peak patterns and botanical classifications had been made. Also it had been found that the area of the exothermic peak system in the complete combustion of peat and fresh plant material bore a simple relationship to the amount of reacting material and to the calorific value determined by a direct method. Many plants had the ability to fix calcium in the form of oxalate and of the lower plants capable of this function lichens were probably the most important since they were frequently during the initial stages of soil formation the only readily observable representatives of the 172 THEKMAL ANALYSIS [Proc.SOC. Aml. Chem. biotic factor. A series of well defined energy changes accompanied the heating of calcium oxalate and these had been used recently to monitor conveniently and rapidly both large and trace amounts of calcium oxalate in specific lichen species. Finally since bacteria played an important part in soil processes and soil - plant relationships the thermal characteristics of a number of species had recently been determined and the initial results showed that the com- plete-combustion curves reflect the carbon to nitrogen ratio. The speaker concluded by saying that the potential of thermal methods was not yet fully exploited and that probably the most promising development at the moment was the incorporation of gas-sampling equipment which would enable qualitative and quantitative determination of the gaseous products associated with the various energy changes.

ISSN:0037-9697    

DOI:10.1039/SA9650200167

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

172 THEKMAL ANALYSIS [Proc. SOC. Aml. Chem. Papers Accepted for Publication in The Analyst THE following papers have been accepted for publication in The Analyst and are expected to appear in the near future. “Vacuum Fusion Analysis with a Mass Spectrometer,” by M. S. Aspinal. “The Analysis of Electrolytic Capacitor Electrolyte The Determination of Chloride and Sulphate in the p.p.m. Range,” by €3. H. Priscott T. G. Hand and E. J. Young “The Solvent Extraction and Colorimetric Determination of Iron with Z-Mercaptopyridine- 1-oxide,” by J. A. W. Dalziel and M. Thompson. “Observations on the lJse of Titan Yellow for the Determination of Magnesium with Special Reference to Soil Extracts,” by K. J. Hall G. A. Gray and L. Ii. Flynn. “A Sensitive and Selective Spectrophotometric Procedure for Determining Phosphorus,” by V. Djurkin G. F. Kirkbright and T. S. \Vest. “The Use of Lithium-drifted Germanium Diodes for the y-Spectrometric Determination of liadioactive Fission Product Nuclides,” by M. F. Ihnham A. ,J. Fudge and J. H. €€owes. “The Analysis and Composition of Potable Spirits The Determination of C, C and C Alcohols in Whisky and Brandy by Direct Gas Chrorriatography,” by D. I). Singer.

ISSN:0037-9697    

DOI:10.1039/SA965020172b

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

November 19651 PUBLICATIONS RECEIVED 173 Publications Received Thc publications listed below have been received by the Editor of Tlze Analyst in which journal Book Reviews will continue to appear. D~CTIONARY OF ORGANIC COMPOUNDS. Editorial Board The late Sir TAN HEILBRON D.S.O. F.R.S. A. H. COOK F.R.S. H. M. BUNBURY and D. H. HEY F.K.S. Managing Editor G. HARRIS. Contributors J. I. G. CADOGAN 1. C. MACWILLTAM Ti. PARSONS C. W. REES K. W. RICKBTTS and C. A. SLATER. Consultant on Nomenclature L. C. CROSS. London Eyre & Spottis- woode (Publishers) Ltd.; E. & F. N. Spon Ltd. 1965. Price (including First Supplement see below) k100. Fourth Edition First Supplement. Editorial Hoard and Editors as above. Pp. vi -+ 207. 1,ondon Eyre & Spottiswoode (Publishers) Ltd. ; E. & F. N. Spon Ltd.1965. Supplied with basic 5 volumes. HTOCHEMISTIXY OF QUINONES. Edited by R. A. MORTON. Pp. xviii 4- 585. London and New York Academic Press Inc. 1965. Price 117s. 6d. London Butterworth and Co. (Publishers) Ltd. 1965. Price 22s. 6d. GAS CHROMATOGRAPHY 1964. Proceedings oC the fifth symposium organised by the Gas Chromato- graphy Discussion Group of the Jnstitute of Petroleum held at the Hotel Metropole Brighton 8-10 September 1964. Edited by A. GOLDUP. Pp. xii + 386. London The lnstitute of Petroleum. Distributed outside the U. K. by the Elsevier Publishing Company Amsterdam. 1965. Price 90s. VITAMIN ASSAY ; T F s r i m METHODS. By ROLF STROH~XKI~R and HEINZ M. HENNING. ‘i’ranslatetl by I). I). Iihman. Weinhelm Verlag Chemie GrnbH. Pp. 360. 1965. Price 1)M 48.00; $12.00.Program for Scientific Translations. Distributed in Great Bri tain and the Commonwealth South Africa Eire and Europe by the Oldbourne Press Tandon. 1965. Price 72s. EPOXIIJES AND THEIR I?F;RIVATIVES. Ky M. S. iYIALrNovsKn. Pp. xviii + 493. Jerusalem 1 srael Program for Scientific ‘Translations. IXstributecl in Great Britain and the Common- wealth South Africa Eire and Europe by the Oldbourne Press London. 1965. Price 144s. Proceedings of the fifteenth Annual Mid-America Spectroscopy Symposium held in Chicago Tllinois June 2-5 1964. Edi ttd by ELWIN N. I > A v r s . Pp. xii + 546. New York Plenum Press. 1965. Price $18.50. By A. RISRKA J. VULTEIIIN and J. ZT~KA. Translated by H. ~VICISZ. Pp. x + 245. Oxford London Edinburgh New York Paris and Frankfurt Pergamon Press. 1965. Price 60s.and Amsterdam W. A. Benjamin Inc. 1965. Price (cloth) $7.70; (payer) $4.35. IAT~ORA-~ORY AN]) ~ ~ O R K S H O P ~ Y O T E ~ S 1962-1964. A.Inst.I’. for the Institute of Physics and The Physical Society. Arnold (l’ublishers) I,td. 1965. Price 60s. ANr\.LTA12 1<ISI-’ORTS OX THE L’ROGR~:SS CHICMrSTIIY ITOR 1964. Volunle 1,xI. Editor 1,. c. ClIOSS I’h.I). A.R.C.S. F.TI.1.C. F’p. vi $- 690. J,ontlon ’The Chemical Society. 1965. L’rice 40s. OXYGEN F:LIcMENmT<Y FOIIMS AND HYDKOGISN I’ICKOX~D~L Uy MICHAEL AKIX)N. Pp. xii -{ 106. New York and AmsteEtfani Mi. A. Benjamin lnc. MrCTH01)S OF HTOCHICMTCAL ANALYSIS. Volume 13. Edited by D ~ v r n GLICK. Pp. x + 488. New York TJontion and Sydney lnterscience Publishers a division of John Wiley & Sons Tnc. 1965. I’rice 110s. ”~‘ItEATISL~ ON ANALYTICAL CH AX I> PRACTICE.Volume 6 Section 73-3 (Conti.tzued) OPTICAL M ited by 1. M. KOLTHOFF and I”FIIixP J’. ELVING with the assistance of Emisr 11. SANDELL. Pp. xxiv + 3347-4246. New York London and Sydney Interscience T3ublis1-1ers a division of John Wiley & Sons Inc. 1965. I’ricc 175s. Editors J. R. A. POLLOCK and K. STEVENS. Fourth Edition in 5 volumes. DICTIONARY OF ORGANIC COMPOIJNIS. ELEMENTARY ELECTROCHEMISTRY. By A. R. J ~ N A R O M.Sc. Ph.D. F.R.1.C. Pp. viii 4- 221. PHOTOSYNTHETIC J3AC IA. By E. N. KONURAT’EVA. Pp. vi + 243. Jerusalem Tsrael DEVELOPMENTS in ApPu RI) SP~CTROSCOPY. Volume 4. Niswim R I I I ~ X ”I’ITiuwrs. $_)UANTUM MICCHANICS TN CHBMISTTIY. T3y MELVIN w. HANNA. Pp. Xi -$- 253. New YOrk Cornpiled and Edited by IXUTH I,ANG T’h. l). 13p.xiv -+ 278. Eclwnrd 1965. Price $7.45. 174 PUBLICATIONS RECEIVED [Proc. SOC. Anal. Chew. 1)IsrILLATIoN. Edited by E. S. PERRY and A. WEISSBERGER. Second Edition. Pp. xx + 838. New York London and Sydney Tnterscience I’ublishers a division of John Wiley & Sons lnc. 1965. Price 180s. SCIENTIFIC RI+:PORT NO. 1. COLORIMETERS WITH FLOW TIIROUGH CELLS A CRITICAL ASSESSMENT 01.’ FOtJR INSTRUMENTS. Pp. 54. The Association of Clinical Biochemists. 1965. Price 13s. 6d. Obtainable from MY. J. T . Tveland Hioclzevnistvy Labovatovy A ldev Hey Childven’s Hospital TivevPool 12. STATIONARY PHASE IN PAPER AND THIN-LAYER CHROMATOGRAPHY. Proceedings of the Second Symposium held at Liblice June 10-12 1964. Edited by K. MACEK and 1. M. HAIS. PI). 358. Amsterdam London and New Vork Elsevier Publishing Company.1965. Price 85s. Amsterdam W. A. Benjamin Inc. 1965. Price (cloth) $7.70; (paper) $4.35. Program for Scientific Translations. South Africa Eire and Europe by Oldbourne Press L,ondon. ORGANIC IXEACTION MECHANISMS. By I<ONAI,T) 13KESLOW. Pp. xii + 232. New Vork and ZSOMERIZATZON OF AROMATIC COMPOUNDS. By V. A . KOPTYUG. Pp. x + 181. Jerusalem Israel Distributed in Great Britain and the Commonwealth 1965. Price 54s. METHODS IN ZONE ELECTROPHORESIS. By JOHN li. SARGISNT B.Sc. 1’h.T). Pp. iv + 107. Poole I’RACIICAL INSTRUMENTAL ANALYSIS. Pp. x +- 263. Amsterdam London and New Yorlr Elsevier Publishing Company. 1965. Price 60s. RINARY C o r j ~ x 1965. Prepared in the llepartment of Pharmaceutical Sciences and published by direction of the Council of the Pharmaceutical Society of Great Britain.Pp. xxxvi + 843. London The Pharmaceutical Press. 1965. Price 105s. Ilorset ‘The British Ilrug Houses Idid. 1965. E’rice 8s. 6d. Edited by J . KRUGERS and A. I. M. KEULEMANS. T,I?CTURSS ON GAS CHROMATOGRAPHY 1964 AGRICULTURAL AND BIOLOGICAL APPLICATIONS. New York I’lenum Press. Hased o n papavs fwesented at the 1964 Covnell 7Jniuevsity Pesticide Wovhshop and the 1964 Canisius College Gas Chvovnatogvaphy 1 nstitade. Part VIII. Prepared by the Committee on Specifications of the Food Chemicals Codex of the Food Protection Committee National Academy oi Sciences-National Research Council. Washington D.C. 1J.S. Department of Commerce. 1965. Subscription price for all parts including binder $25. Edited by 1,. K. MArrTrcK and H. A. SZYMANSKI. 1965. Price $12.50. Pp. viii + 256. Fooi- CHEMICALS Con~x. Pp. iii-vi + 473-583 (loose leaf). lncluded in this aye vei!&zcement pages fov the oviginal Pages iii-vi and the index. GUAIANOLIDISS ANI) GISRMACRANOLIDES. By FRANTISEK SORM and LAI)TSIAV DOLEJS. I’p. 153. f’aris Hermann. 1965. Price 48 I;.

ISSN:0037-9697    

DOI:10.1039/SA9650200173

出版商:RSC    

年代:1965

数据来源: RSC

摘要:

174 PUBLICATIONS RECEIVED [Proc. SOC. Anal. Chew. Notice BRITISH STANDARD INSTITUTION DRAFT SPECIFICATIONS A FEW copies of the following draft specifications issued for comment only are available to members of the Society and can be obtained from the Secretary The Society for Analytical Chemistry 14 Relgrave Square London S. W. 1. Draft Specification prepared by Sub-committee LBC/1/5-Volumetric Glassware. D65/9576-Draft R.S. Specification for Ostwald-Folin Pipettes (Revision of R.S. 773). Draft Specification prepared by Sub-Committee LBCjl/4-Lampblown Glassware. D65/9815-Draft B.S. Specification for Soxhlet Extractors (Revision of B.S. 2071).

ISSN:0037-9697    

DOI:10.1039/SA9650200174

出版商:RSC    

年代:1965

数据来源: RSC