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21. |
Book reviews |
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Analyst,
Volume 104,
Issue 1240,
1979,
Page 700-704
P. M. A. Sherwood,
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PDF (640KB)
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摘要:
700 Book Reviews Analyst, Jzcly, 1979 PHOTOELECTRON SPECTROSCOPY AND MOLECULAR ORBITAL THEORY. By R. E. BALLARD. Pp. xii + 192. Bristol: Adam Hilger. 1978. Price LlS. The book attempts to present the main features of molecular orbital theory through the interpretation of gas-phase ultraviolet photoelectron spectroscopy, and to cover the chemical applications of photoelectron spectroscopy. It begins with a preliminary survey of traditional molecular and atomic spectroscopy, covering angular momentum, spin and atomic energy levels and their calculation by self-consistent field theory. The second chapter introduces molecular orbital theory with energy-level diagrams and photoelectron spectra of hydrides isoelectronic with neon, hydrogen halides, water and ammonia. Later chapters cover diatomics, molecules related to ethylene, xenon compounds and tetrahedral and octahedral molecules, including transition metal compounds.The molecular orbital energy diagrams are nearly all illustrated by electron-density contour diagrams of Jorgensen and Salam, “The Organic Chemist’s Book of Orbitals,” Academic Press, 1973. There are separate chapters on vibrational structure illustrated by many examples with group theoretical analysis and coverage of Jahn - Teller effects, spin - orbit coupling, again illustrated by examples, and the angular distribution of photoelectrons. Each chapter ends with a useful set of problems. The approach to the subject presents an original attempt to develop molecular orbital theory through increasingly complex photoelectron spectra, which has the advantage of making the theory immediately relevant, although the depth of the theoretical coverage is somewhat varied.For example, the treatment of atomic charge and its relation to core electron binding energy and dipole moments is oversimplified. The book is well written and produced, with many clear diagrams and useful tables, and would be a valuable book for research students in this field and for postgraduate courses, although at LlS it is rather expensive. P. M. A. SHERWOOD AN INTRODUCTION TO MICROSCOPY BY MEANS OF LIGHT, ELECTRONS, X-RAYS OR ULTRASOUND. By THEODORE GEORGE ROCHOW and EUGENE GEORGE ROCHOW. Pp. xvi + 368. New York and London: Plenum. 1978. Price fllS.58. The dust jacket claims that this is the first book to deal with all aspects of microscopy; however, a number of topics such as cine and television, fluorescence and infrared microscopy are not dealt with, and measurements are not properly described.Most of the topics treated are covered in a rather wide-ranging approach that occasionally lacks depth. After a brief history of light, electron, field emission and acoustic microscopy, a second chapter deals with definitions of basic terms and principles. Simple and compound microscopes are then treated in a somewhat fragmented manner, but this is followed by an interesting and useful chapter on reflected light. The Pointolite source mentioned on p. 75 is now obsolete. A group of three chapters deal with polarised light, fibres and crystals in some detail. Photomicrography receives a wide-ranging treatment, and the authors favour a combination of an exposure meter and photo- graphic records to achieve satisfactory exposures.A very useful chapter is that on contrast, which usually receives less consideration than magnification and resolution. Interference micro- scopy is well treated in a separate chapter, although only a few applications are described. A wide range of microscope stages are covered, including hot and cold stages, and other special cells such as the stage refractometer. The chapter on transmission electron microscopy covers instrumentation reasonably well but, as the authors say, specimen preparation is too large a topic to discuss in detail; their summary on preparation covers powders, surfaces, ultramicrotomy and freeze-fracturing, but does not mention freeze-etching.Scanning and field emission microscopy are given separate chapters and good summaries are given. The problems involved in the development of X-ray microscopes are discussed in a short but informative chapter, and the long-term promise of X-ray holography is mentioned. The final chapter deals with the newer technique of acoustic microscopy, in which the modifications of an ultrasonic wave by a specimen are converted, in video fashion, to give an acoustic image. The technique shows microvariations in density, stiffness, viscosity and other rheological properties, and shows promising applications to biological tissues and medical problems.JuIy, 1979 BOOK REVIEWS 701 An attractive feature of the book is that for most types of microscopy discussed, the authors consider all of the fundamental parameters such as resolution, useful magnification, contrast, aberrations, depth of field and focus, field of view and, where appropriate, working distance.A disadvantage is that the field of microscopy is now so vast that encyclopaedic coverage is difficult for two authors to achieve. The modern answer to this problem is the multi-authored book with 10 to 20 authors or more, each expert in a particular field. Despite some shortcomings, this is a thought-stimulating book, with a fresh approach to many familiar topics, and one that can be recommended for general reading. G. W. WHITE ENVIRONMENTAL POLLUTION ANALYSIS. By P. D. GOULDEN. Heyden Internatiovlal To+cs in Science. Pp.xii + 209. London, Philadelphia and Rheine: Heyden. 1978. Price $16.50; L8.30; DM53. This volume is one of a series on topics in science, indeed one monograph has already been published describing the role of classical liquid - solid chromatography in environmental analysis. When concern for the environment became all the vogue about 10 years ago, it was obvious that a large stumbling block was the almost log-jam problem in developing methods of analysis for an ever increasing number of pollutants. The basic problem was that, as the majority of such pollutants are physiologically active at low levels, typically micrograms per gram or below, then there was a need for both matrix removal techniques as well as very selective methods of deter- mination for the isolated or partially purified product.In addition there are two forms of physiologicallv active material, inorganic and organic, in nature. So much work has been put into the topic and great advances made, as many of the techniques are specialised ones often full of intricacies and fine detail, that the field has tended to become extremely specialised and the scientists involved almost cabbalistic in outlook. Such work was badly needed to replace or supplement the older methods that involved themselves with bulk parameters, e . g . , BOD. These classical methods do not inform the analyst of the fate of a particular organic compound in the environment. Hence, this volume attempts to place some order and credence to the methods that have been adopted and is an attempt to provide a bridge of explanation so that non-analytical scientists can become aware of how environmental samples should be collected and how such low levels of pollutants may be determined.The methods are described in the order of how they are carried out; thus the first chapter is concerned with sampling. The methods are divided under the headings of the types of samples that are normally taken, e . g . , water and sediment. However, what is surprising is that although fish are dealt with as an example of the upper trophic aquatic layers, no mention is made of procedures for terrestrial or avian species. Perhaps this reflects the interest of the author. Next comes a chapter dealing with the determination of metals, which is basically a description of the more usual instrumental techniques, e .g . , atomic spectroscopy and electrochemical methods. It is surprising that atomic fluorescence is given more space than molecular-absorption spectro- photometry in view of the relevant importance of the respective techniques. Chapter 3 discusses an area of work-cum-research that is involved with metal speciation, so it starts with mercury alkyls, which are described in fascinating detail. Next come lead, selenium and arsenic, all as alkyls, each section carrying a brief historical introduction to the topic. The chapter is finally completed with a full discussion on the speciation of metds in natural waters, which even includes a section on complexing capacity with a full description of the Batley and Florence scheme for classifying metals.The following chapter is entitled “Analysis of Inorganic Materials,” which is frankly a misnomer as it deals largely with the analysis of non-metals in aqueous solution especially anions such as sulphate, chloride and phosphate. Within this context the differentiation between the various forms of phosphorus, e.g., particulate phosphorus, soluble orthophosphate and organic phosphorus, are made, together with the appropriate analytical scheme. The determination of particulates, especially asbestos, using electron microscopy completes the chapter. After a short chapter on radionuclides there is a fairly lengthy chapter on the identification and determination of organic materials. The significance as well as the methods of determining bulk parameters, such as BOD and COD, are described first, followed by the methods for chemicals under general headings such as surfactants, phenols, tannins and complex ions.The chapter next goes on to discuss methods for organochlorine pesticides and industrially used compounds, organophosphorus pesticides, poly- nuclear aromatic compounds and finally herbicides such as the triazines and chlorophenoxy702 BOOK REVIEWS Analyst, Vol. 104 materials. However, we next move back to techniques, in that the chapter closes with about 15 pages of discussion on gas and liquid chromatography followed by mass spectrometry. Bluntly, this is almost placing the cart before the horse in that to be consistent with Chapter 2 it may have been better to discuss the techniques of identification and determination and then illustrated the chapter with examples, but as it stands Fig.6.2 for the separation of pesticide mixtures on page 153 comes some 15 pages before an electron-capture detector is discussed on page 168. Therefore, the organisation of this chapter leaves more than a little to be desired. Chapter 7 is concerned with the assay of micro-organisms, which is novel in that this is carefully avoided in most of the classical analytical textbooks, while the final chapter describes continuous monitoring methods including methods of chemiluminescence for ozone and trioxides of nitrogen. Thus, the book is unconventional in the approach that is adopted to analytical chemistry but perhaps that is no bad thing for the subject. However, I do believe that reorganisation of some of the material within the chapters is needed.A more serious error is the lack of a chapter or section on precision, accuracy and statistical validity of results, as from the Preface we are led to believe that the data acquired will be used to enforce legislators’ decisions. The first question that is asked in such instances is “what is the quality of the data ?” Likewise a discussion on the use of standard reference materials for the calibration of instruments would have been welcome, as in many instances they are the limiting factor in assessing the performance of various instru- ments. Thus, the book is a very interesting one, certainly it is a good attempt to cover a vast, complicated and growing subject, but perhaps the subject is too wide to discuss adequately in such a slim volume; hence the adverse comments.The book is well produced and is furnished with plenty of clear diagrams, tables and some photographs. For the worker in the field it will be a stimulating book to read as well as for workers about to enter this rapidly growing area. G. NICKLESS IARC MONOGRAPHS ON THE EVALUATION OF THE CARCINOGENIC RISK OF CHEMXCALS TO MAN. COLOURING AGENTS AND MISCELLANEOUS INDUSTRIAL CHEMICALS. Pp. 400. Lyon : International Agency for Research on Cancer. Distributed by the World Health Organi- zation. Available in the UK through HM Stationery Office. 1978. Price SwFr50; $20. Volume 16. SOME AROMATIC AMINES AND RELATED NITRO COMPOUNDS-HAIR DYES, This volume is a review of published data on substances used as ingredients of hair dye and other cosmetic preparations, and data on likely impurities in such ingredients, which naturally have other uses.There follow the monographs, eight on “Hair Dyes” (oxidation colourants) , nine on “Colouring Agents” (dyestuffs including semi-permanent colours) and fifteen on “Miscellaneous Industrial Chemicals,” being mostly dyestuff intermediates. A half, or more, of each monograph concerns the chemistry of the substance including material on identity and nomenclature, properties of pure and commercial substances, production and use and analysis. As much biological testing is carried out on commercial products, there is the possibility, if not probability, of variation between different commercial preparations of a given substance ; hence the importance of identity and nomenclature.However, it appears that the sort of information given a t the beginning of these monographs is not always carried through to reports on biological tests. The section on production and use gives some idea of relative amounts manufactured and the principal end-products. This leads naturally to a consideration of the biological data, leaving analysis on one side for a moment. I cannot help but feel that the frequent indecisive results reported herein hardly justify the animal sacrifice necessary to obtain them; I will refrain from comment on the expenditure of other resources involved. Hopefully bacterial and tissue testing can replace live animal experi- mentation to an increasing extent and sophistication of interpretation can reduce the scale of experimentation.This volume deals with 32 substances. A recent list included 153 substances with an aromatic amine function, stated to be in current use by European manufacturers in various types of hair colouring products, indicating the massive Two introductory chapters are included, the second being specifically about hair dyeing. Further studies are called for on many of the substances. Quantity of testing arises in another direction.July, 19 79 BOOK REVIEWS 703 problem facing an enforcement agency that tries to exercise thorough and systematic control of cosmetic products. The monographs include a variety of data, including much from less readily available sources, whilst making some surprising omissions. Thus, no reference is given to Silk, Perdih or Tonet, all of whom produced separation schemes that included at least some of the dyestuffs listed in the monographs, even though the titles of their papers referred to lipsticks.Tonet’s scheme has been chosen as the basis for a standard EEC method for the identification of all cosmetics colourants, other than the oxidation colourants. Although HPLC looks so promising for application in this field and is the technique used in a number of recent studies on dyestuffs analysis, only one reference to this technique was noted in this volume. It has to be admitted that this book seems likely to become dated rather quickly in respect of its commentary on analytical techniques. Overall, then, the book constitutes a review, and probably a unique one, of the work done to evaluate the carcinogenic hazard of hair dye ingredients and is at the same time a useful com- pendium of their chemical and analytical properties.It is probably an essential source book for toxicologists, but for chemists working in the field it still provides much of interest. At USQ620 it is not exorbitantly expensive. Coming a t last to the sections on analysis we are on somewhat firmer ground. M. J. GLOVER PROCEEDINGS OF THE 1976 INTERNATIONAL CONFERENCE ON MODERN TRENDS IN ACTIVATION Volumes Edited by T. BRAUN, E. BUJDOS~, R. HENKELMANN, J. I. KIM, F. LUX, H. Volume 1978. Price ANALYSIS, MUNICH, FEDERAL REPUBLIC OF GERMANY, 13 TO 17 SEPTEMBER, 1976. I and 11. STARK and R. ZEISLER. I, pp. iv + 955; Volume 11, pp.iv + 1008. $175 (2 volumes) . Reprinted from the Journal of Radioanalytical Chemistry. Budapest: AkadCmiai Kiad6. The series of international conferences on Modern Trends in Activation Analysis was initiated by Professor R. E. Wainerdi and the present reviewer at Texas A & M University in College Station in December 1961. The first conference was a relatively informal affair, but was SO successful that an International Committee was set up and further conferences were organised in College Station (1965), Gaithersburg (1968), Saclay (1972) and Munich (1976). The proceedings of the first three conferences were published privately by the local organisers, but starting with the 4th conference the proceedings have been published first in the Journal of Radioanalytical Chemistry and later as a hard-backed collection.The two volumes under review are therefore simply bound versions of volumes 37, 38 and 39 of the above journal and, as such, they perpetuate the typographical errors of the original. The contents, comprising 173 contributions, are divided up into some ten subject areas with the Plenary and Special Lectures brought together in an opening section. These lectures cover the interrelation of activation analysis and radiochemistry (H. J. Born), the medical significance of the essential biological metals (I. J. T. Davies), the discovery and study of the nuclear reactor in Oklo (E. Roth), chemical fractionation in the solar system (J. W. Morgan) and analytical methods applied to water pollution (G. Baudin). “Fundamental Contributions and Technical Developments’’ includes 18 papers, which mainly show an extension of radiation measurement techniques to include practical use of X-ray spectro- metry, and the use of a range of bombarding particles other than neutrons, including even heavy ions.“Biological and Biomedical Applications” is the largest section with 32 papers and, together with the related environmental/ecological section, forms almost one third of the whole. Several papers cover in vivo analysis, but the majority deal with the determination of a wide range of trace elements in blood, organs and tissue. These were concerned with establishing normal levels, rather than measuring abnormal conditions and no new connections between trace elements and disease were reported. A surprising proportion of the 29 papers in the section on “Environmental and Ecological Application” describe pre-concentration techniques.It can be argued that, if the risks of loss or contamination in such a procedure can be overcome or accepted, there are cheaper and simpler methods than activation analysis suitable for use. A whole range of environmental investigations are reported and it is noteworthy that forms of power generation, other than nuclear, are now receiving the attention of the environmentalists.704 BOOK REVIEWS Analyst, Vol. 104 Although many of the 20 papers in “Materials Sciences and Industrial Applications” deal with the now well established analysis of high-purity materials, there is obviously a growing interest in finding out more than just the general concentration of an impurity element; several papers therefore describe methods for obtaining trace element profiles.Genuine on-line analysis still requires considerable development, but the 14-MeV neutron generator is being used for the routine automatic determination of protein in foodstufis and the components of fertilisers. In “Geo- and Cosmo-Sciences,” 19 papers cover the multi-element analysis of a range of terrestrial, meteoritic and lunar material, but the significance of the results obtained is beyond the scope of this review. The nature of the sample matrices necessitates radiochemistry in many instances, and a number of interesting group separation schemes are reported, but it is surprising how many elements can be measured purely instrumentally in such materials.Virtually all the 13 papers in “Archaeology, Art and Forensic Sciences” deal with the trace- element characterisation of ancient objects with a view to group classification, exploration of population movement, evaluation of technological development or identification of fakes. From the 11 papers in “Accuracy and Precision” it would appear that one of the major problems of gamma-ray spectrometry still lies in the measurement of the area of a photopeak, although a few papers examine the over-all accuracy and precision of the method itself. In the related areas of “Sampling and Homogeneity Control” (6 papers) and “Standard Materials” (4 papers) the major concern appears to be homogeneity, of real as well as reference samples, but the problems of long-term storage are also discussed.The 6 papers in “Comparisons with Other Analytical Methods” seem more concerned with justifying the validity of the activation analysis technique than with actually comparing the merits and disadvantages of the methods being considered, but a series of IAEA inter-comparisons involving the determination of chromium by more than 8 different methods in a range of inter- comparison samples are described by the author as “a catalogue of failure.” He concludes “most of the results of chromium analyses, reported to IAEA in recent years, must have been subject to significant sources of error of which the analysts were presumably unaware.” The final discussion paper was concerned with representative sampling, but no firm recom- mendations were made. Overall, it is difficult to see how the expenditure of $175 on these two volumes is likely to be justified.Those analysts who were fortunate enough to be able to attend the conference will have their bound copies of the pre-prints (which are not so different from the final version), while the majority of librarians who might contemplate purchase will probably already have the Journal of Radioanalytical Chemistry on their shelves. D. GIBBONS RESONANCE RAMAN SPECTROSCOPY AS AN ANALYTICAL TOOL. Edited by A. J . MALVEGER. 1977 Eastern Analytical Syynposiuvn Series. Pp. viii + 84. Philadelphia : Franklin Institute Press. 1978. Price $10.50. I t has long been known that the intensity of Raman spectra can be greatly enhanced by using an exciting frequency close to an absorption band of the substance, a technique known as resonant Raman spectroscopy. A more recent development provides signals using two input frequencies, perhaps two dye lasers, separated by the Raman frequency. The best known version of such experiments is Coherent Anti-Stokes Raman Spectroscopy usually known as CARS, in which the anti-Stokes emission is detected. But there are other versions where the absorption or amplifica- tion of one of the exciting frequencies is detected. These techniques can be combined with resonant Raman enhancement and indeed a sensitivity of 10-7 mol dm-3 for vitamin B,, is claimed, but the noisy spectrum presented for Adriamycin at 10-3 mol dm-3 is far from impressive. How- ever, the analytical use of these techniques is new and the most effective methods of treating turbidity, background signals and fluorescence may not yet have been found. As yet no complete commercial equipment, as opposed to components, seems to be available. It was therefore opportune that the seventeenth Eastern Analytical Symposium (USA) in 1977 was devoted to these subjects and now four of the review/research papers have been photocopied and published in soft covers. The expertise of 1977 in the analytical field is contained therein, but the changes and improvements remain rapid. The price of $10.50 for 80 pages of open typing of ephemeral material is just, but only just, value for money for the analyst who wishes to be forewarned of a technique that may, or more likely may not, have an important future. D. H. WHIFFEN
ISSN:0003-2654
DOI:10.1039/AN9790400700
出版商:RSC
年代:1979
数据来源: RSC
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