Integrated Approach to Analytical Separation Methods

tion processes, and physical-mechani- cal-chemical contributions to separa- tion. The general approach here ... and standard states are wrong or mis- ...
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Integrated Approach to Analytical Separation Methods Separation Methods in Chemical Anal­ ysis. James M. Miller, χ + 309 pages. John Wiley & Sons, Inc., 605 Third Ave., New York, N.Y. 10016. 1975. $14.95

Reviewed by Lloyd R. Snyder, Technicon Instruments Corp., Tarrytown, N.Y. 10591 This book provides an integrated approach to analytical separation methods, with about half the book de­ voted to general theory and half to a description of individual methods. The coverage is reasonably complete (no important areas have been over­ looked), the treatment is up-to-date with a good bibliography, the book is well produced with few typographical errors, and the single authorship pro­ vides a coordinated and even handling of different topics. The general aim of the book is to provide "a unifying outline of the major methods of (analytical) separa­ tion," with attention to the "basic theory of separation science." The level seems appropriate to an under­ graduate course on analytical separa­ tions. The scope, size, and theoretical emphasis of the book may restrict its value as a general reference book on the subject. However, the level and style will appeal to many who are now working in the field. The first six chapters provide a gen­ eral theoretical orientation, where such topics are discussed as subject classification and nomenclature, ther­ modynamics and kinetics of separa­ tion processes, and physical-mechani­ cal-chemical contributions to separa­ tion. The general approach here is similar to that followed by other books and generally used in the field—with some important differences. The de­ sire for a unified, self-consistent treat­ ment has led to innovations in both classification and nomenclature. In many cases these differ from current practice; for example: the widely used separation factor is replaced by sepa­ ration quotient, adsorption is referred to as a partition process, chemisorption is defined in terms of the strength of the interaction (rather than the speed of equilibration), and there is some confusion in the use of partition coefficient vs. capacity factor. Al­

though the changes proposed may have ultimate merit, they may also confuse the beginner trying to make sense out of analytical separations as presently practiced. I was somewhat disappointed in the treatment of thermodynamics, which was short and inflicted with occasional errors; example: on page 37 it is stat­ ed, for an ideal solution of A and B, "no interactions are present between (molecules) A and B." Similarly, sev­ eral statements on activity coefficients and standard states are wrong or mis­ leading. The discussion of the Donnan equilibrium on pages 46-7 came across as confusing and unclear; however, the discussion of intermolecular forces is well done and simple. Adsorption phe­ nomena receive a rather uneven treat­ ment which is marred by several er­ rors and ambiguities (the discussion of adsorption isotherms is particularly disappointing). In these chapters one begins to notice a peculiar writing de­ fect, where the unnecessary addition of words such as "however," "other," and "therefore" (for stylistic pur­ poses?) leads to confusion over the in­ tended meaning of a sentence (see page 67, par. 3; page 71, line 6; page 106, line 5 from bottom, as examples). Chapters 8 and 9 on band broaden­ ing and separation (mainly for appli­ cation in chromatography) conclude the general treatment of separation theory. Although the treatment here is more or less conventional, there are important differences. My feeling was that these chapters would be more useful after a student had been ex­ posed to these topics elsewhere, as I found the subject matter hard to fol­ low in an initial reading. Chapters 7 and 10-17 treat the indi­ vidual separations methods. These in­ clude distillation, liquid-liquid extrac­ tion, chromatography (general), gas chromatography, liquid chromatogra­ phy, plane chromatography, zone elec­ trophoresis, and dialysis. The overall emphasis is heavily on the chromato­ graphic methods, and most of the lat­ est developments in this area are dis­ cussed. The discussion of the liquid chromatography methods stands out particularly, a result no doubt of Mil­ ler's active research in this area.

An overall assessment of the book depends pretty much on the reader and what he is looking for. This is probably the best of recent "small" books on the subject and certainly the most up-to-date. A really good book for undergradu­ ates has probably not yet been writ­ ten, although the second edition of this book could approach that goal. Anyone wanting a reference book on individual separation methods will do better with Heftmann's forthcoming 3rd edition of "Chromatography," al­ though this book is a useful supple­ ment.

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K.0.NEUIE AMD C.JLMMEWMD Liquid Scintillation Counting. K. D. Neame and C. A. Homewood. viii + 1 8 0 pages. Halsted Press, 605 Third Ave., New York, N.Y. 10016. 1974. $13.75

Reviewed by Donald L. Horrocks, Sci­ entific Instruments Division, Beckman Instruments, Inc., 2500 Harbor Blvd., Fullerton, Calif. 92534 This book, as pointed out by the au­ thors, relates many of their experi­ ences and observations while using liquid scintillation counting tech­ niques. However, most of these are so closely allied with the operation of a single type of counter (Nuclear-Chica-

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Books

go) that many readers will have difficulty in relating this information to a different type of counter that they may have at their disposal. Only a person quite knowledgeable in the workings of different liquid scintillation counters is able to see how the information is translated to be applicable for different types of counters. This book is well written and easy to read. It should provide a good introduction to many of the practices of liquid scintillation counting. However, for those more interested in the theory of the scintillation process or special applications and sample preparation techniques, it will be necessary to seek other sources. There are some statements in the book which I feel deserve special comment. The authors relate the effect of temperature on the counting efficiency of different quenched samples (page 53). The scintillation process is not temperature dependent (at least over this reported temperature range); therefore, the effect they report must be due to some special property of the type of samples used. The authors state in several places (pages 58, 60, and 159) that samples in plastic vials usually give lower counting efficiency than the same samples in a glass vial. This is just the opposite effect as reported by many other investigators. They further state that xylene gives a 10% greater counting efficiency than toluene when used as a scintillation solvent (page 68). p-xylene gives 10-20% higher light output (scintillation efficiency), but this is not directly translated into an equal increased counting efficiency. In Chapter 7 the authors talk about using the same channels that are used for sample counting for the measurement of the external standard counts (or ratio of counts). But they fail to mention the necessity to correct the measured counts for the contribution of the sample counts before the external standard count or ratio is calculated. Most modern instruments have two special counting channels separate from the sample counting channels and designated for counting the external standard. Many instruments even make the correction for sample count contribution and calculate the external standard channel ratio value. Chapter 8 is concluded with a statement (page 128) that the effect of equal amounts of quench agents is different for single-labeled and dual-la-

beled samples. This is not true; if it were, it would not be possible to use single isotope quench curves for calculations of the amounts of the two isotopes in a dual-labeled sample. In Chapter 11 the authors state that linear amplification is more stable than logarithmic amplification (page 154). In most modern instruments both of these types of amplification are equally stable. In spite of these differences of opinion, I feel that this book was well worth reading. If other readers are able to take the large amount of information presented and apply it to the many different types of counters, I am sure that they too will find this book informative.

Principles of Chromatography Chromatographic Methods. R. Stock and C. B. F. Rice, viii + 383 pages. Halsted Press, 605 Third Ave., New York, N.Y. 10016. 1974. $8.95

Reviewed by Erich Heftmann, Western Regional Research Center, U.S. Department of Agriculture, Berkeley, Calif. 94710 As the editor and coauthor of the third edition of "Chromatography" (Van Nostrand Reinhold Co.), which is about to appear at approximately four times the price of the third edition of "Chromatographic Methods" and as one who has been aggravated by seeing his name and the names of his associates misspelled several times (refs. 22 and 23, page 102, and page 371), I had a very stern attitude when I started to read this book by Stock and Rice. However, as I continued to read, my mood gradually changed from a grudging admission that British authors usually express themselves much better than Americans to a genuine admiration for their lucid treatment of the principles of chromatography. Stock and Rice must be great teachers to organize such a vast body of information so well and to present it in such a beautifully clear and interesting manner. "Chromatographic Methods" covers not only the theory and techniques of liquid column, paper, gas, and thinlayer chromatography at the level of a college textbook, but it also offers a short laboratory course of 22 experiments, suitable for adoption by chemistry departments of modest means. In addition, the book contains valuable directions for the construction of inexpensive equipment (including detectors for gas chromatography) and lists of references and visual aids. The authors have also tried to include electrophoresis, but in my opin-

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ion, without success. The treatment is inadequate (five pages + one experiment) and obsolete. I regret to say that I have also found large sections of the book out of date. This is a common fault of many textbooks, especially those which have gone through several editions. However, this does not detract from their teaching value. The principles of chromatography can be very well learned from, e.g., obsolete methods of paper chromatography. I consider this an outstanding textbook and recommend it warmly to college teachers and students, who will find it a great bargain (the book is also available in paperback edition). I do not recommend it to advanced students, researchers, and practicing analysts, however, because many of the techniques, applications, and references are either obsolete or indiscriminately selected. It is just impossible for two teachers, no matter how great they are, to keep up with the latest developments in all ramifications of chromatography and to select the best methods from the immense volume of current literature on this subject.

Effects of Pollutants on Biological Systems Environment and Pollutions: Sources, Health Effects, Monitoring and Control. Francis K. V. Leh and Richard K. C. Lak. xx + 288 pages. Charles C Thomas, 301-327 East Lawrence Ave., Springfield, III. 62703. 1974. $14.75

Reviewed by Arthur C. Stern, Department of Environmental Sciences & Engineering, University of North Carolina, Chapel Hill, N.C. 27514 Although this work has seven chapters and four appendices on air pollution and only five chapters and three appendices on water pollution, there is about an equal coverage (approximately 140 pages) of each subject, including a 28-page chapter on chemical analysis of air pollutants and a 16page chapter on chemical analysis of water pollutants. These latter are too abbreviated to qualify the book as a reference or guide to analysis, measurement, or monitoring of pollutants or as a text for the training of chemists. The preface states that the book is "intended for students at college level and for research workers from many disciplines of environmental study." In addition to analysis, its chapters on air pollution cover photochemical and "London-type" smog; the effects of air pollution on vegetation, animals, materials, man, and the atmosphere; and 21 pages on air pollution control. Its chapters on water pollution cover trace metals, pesticides, nutrients, and 18 pages on waste water treatment.

Here again, the number of pages on engineering control of air and water pollution are too few to qualify the book for engineers or engineering students. Discounting the chapters on measurement and control, what remains is a set of chapters on air and water pollution effects on the environment. Since these effects are not treated in an ecological context and since environmental concerns beyond air and water are not discussed, the book fails to qualify for reference or text for courses in ecology or environmental studies. The greatest strength is in its discussion of the biochemistry and effects of pollutants on biological systems and of the mechanisms of their toxicity. The book is attractively printed; the figures are sharp; there is extensive use of structural formulae of organic substances, and there is a six-page subject index. Each chapter is terminated by a reference list.

An Aid to Spectroscopists Polymer Spectroscopy. Dieter O. Hummel, Ed. xii + 401 pages. Verlag Chemie GmbH, Weinheim/Bergstr., Germany. 1974. DM 125 (English)

Reviewed by J. P. Heeschen, R. A. Nyguist, and J. C. Tou, Analytical Laboratories, Michigan Division, Dow Chemical U.S.A., Midland, Mich. 48640 This multiauthored book covers vibrational spectroscopy, high-resolution nuclear magnetic resonance, electron spin resonance, and mass spectrometry of synthetic polymers. It is well organized. All sections have the same format, and a single index is provided. The authors are commended on their English style, in view of the fact that only one, Hendra, resides in an English-speaking country. The literature is covered into 1971. Each section consists of a brief introduction to the method, a detailed exposition on fundamental aspects of the method as applied to polymers, and a presentation of significant applications that have been made. Corollary to this approach is the education the reader may acquire regarding concepts of polymer structure. The vibrational analysis of highly ordered polymers is treated thoroughly by H. Tadokoro and M. Kobayashi. D. O. Hummel discusses IR spectroscopy applied to polymer structure elucidation. Raman spectroscopy, experiment and applications, is presented by P. J. Hendra. The NMR section (E. Klesper and G. Sielaff) is directed toward elucidation of taxis in homopolymers, se-

quencing in copolymers, and chain conformation. A good discussion of the basic statistics of polymer chain growth is included here. A bibliography of polymers studied by NMR is furnished. H. Fischer and D. O. Hummel cover electron spin resonance as applied to irradiated polymers, study of free-radical polymerizations in both liquid and solid state, and free radical formation by mechanical working of fibers. The mass spectrometry section (D. O. Hummel, H. D. Schnuddemage, and K. Rubenacker) deals almost entirely with pyro-field ion mass spectrometry, where the polymer is pyrolyzed very close to a field ion source. It is gratifying to find in this book both rigor and depth in the treatment of significant topics. By concentrating on classic systems and on fundamentals of techniques, the authors have produced a working reference which can guide the user to applications in new systems. Of necessity, the concentration on some topics has led to deletion of others. Most notable are omissions of NMR of solid polymers and pyrolysisGC-electron impact mass spectrometry. C-13 NMR is given only short discussion (this is not serious, however, because general principles are transferable from proton considerations). For X-ray and electron diffraction the editor refers us to another book. There are some weaknesses. The introduction to mass spectrometry dismisses pyrolysis-GC-electron impact MS as "quite pretentious," an attitude with which we cannot agree, since this technique is better for structure elucidation and quantitative measurements of pyrolyzates. The introduction to MS also is more qualitative than the other introductions, and the only mathematical relation it contains is erroneous as printed—the mass of a metastable ion, m*, is given as m* = m\lm\, but should be m* = m\lm\. In addition, mi and m% are not defined. The chapter on applied IR contains a few errors in interpretation and fails to note the presence of nonpolymer absorptions in some illustrated spectra. The NMR discussion of sequencing in PVC becomes confused when the authors go through an apparently unconscious transition from speaking of sequences of placements of monomer units to speaking of sequences of monomer units themselves. There are typographical and grammatical errors, but they do not alter the sense of the text. An incorrect address is given in a reference to one author of this review (R.A.N.). In summary, the strengths of this book far outweigh its weaknesses. It is recommended as a good, authoritative

Books single volume on the application of vibrational spectroscopy, high-resolution NMR, ESR, and pyro-field ion mass spectrometry to synthetic polymers. It should be most useful to spectroscopists, both as an aid in their own areas of expertise and as a means for evaluating other approaches to polymer problems.

New Books Selected Methods in Determination of First Row Transition Metals in Natural Fresh Water. Richard G. Whitney and Terence H. Risby. xi + 94 pages. The Pennsylvania State University Press, 215 Wagner Building, University Park, Pa. 16802. 1975. $3.50

Intended as a reference, this paperbound book reviews the most recent literature covering the determination of trace quantities (less than 100 ppm) of first row transition metals in water by 10 methods: colorimetry, spectrophotometry, atomic fluorescence spectrometry, X-ray fluorescence spectrometry, atomic absorption spectrometry, conventional and pulse polarography, anodic stripping voltammetry, ion-selective electrodes, neutron activation analysis, and chromatography. The monograph contains seven chapters, the first three of which are devoted to an introduction and a discussion of sampling procedures and sources of these metals. The next three chapters cover the selected spectral, electrochemical, and other methods as listed above. In each of these sections describing different methods, a brief and easy-to-understand discussion of the theoretical background of different instrumentation is found. The last chapter outlines a procedure for comparison of these methods. Impact of Lasers in Spectroscopy. S. Ezekiel and S. M. Klainer, Eds. iii + 1 6 0 pages. Society of Photo-Optical Instrumentation Engineers, P.O. Box 1146, Palos Verdes Estates, Calif. 90274. 1974. $32

This 49th volume of a series contains the proceedings of a seminar held in August 1974 for the purpose of reviewing the current state-of-the-art and the future of laser spectroscopy. Priced rather high for a paperbound photo-offset copy of author-furnished typewritten text, the book includes 23 papers presented at four sessions entitled Laser Spectroscopy, Lasers, Environmental Monitoring, and Applications.

ANALYTICAL CHEMISTRY, VOL. 47, NO. 9, AUGUST 1975 · 847 A