Books and Software: A complete lesson on chromatography

and Software. Mixed Bag of Particles. Particle Size Distributions III. Edited by Theodore Provder. Oxford University Press. 198 Madison Ave. New York,...
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Mixed Bag of Particles volves the selection of a priori distribution forms or requires some heroic attempt to extract a distribution from various measurements of the unfractionated ensemble. The general failure of such techniques has long been recognized in a quantitative sense (even truly monodisperse polystyrene latex spheres yield a distribution breadth). From a qualitative sense, they also often fail as well, as seen by examining a bi-modal distribution formed by mixing Particle Size Distributions III two monodisperse contributions. In conEdited by Theodore Provder trast, the several articles showing the appliOxford University Press cation of fractionation procedures (CHDF 198 Madison Ave. and FFF, for the most part) before sizing New York, NY 10016 confirm the significance and validity of this 1998, 368 pp, $125 technique for extracting a meaningful and valid distribution This reviewer has long felt that the books in the ACS Symposium Series have been This book contains some other minor "mixed bags". This book is no exception. flaws that detract from its intended integraLike many of its companion volumes, it tion. It is replete with examples of poor suffers from poor editing and the inclusion editing, including the frequent use of the of irrelevant contributions. The title of the archaic term "micron" in many of the conbook is Particlleize Distributions III, yet tributions. Reference styles are quite varied 30% of the contributions do not even disand inconsistent, even within a single concuss the subject. The contributions span a tribution. Some illustrations are of poor broad range of quality—from exceptional quality, and figure caption styles are not to rejectable. Noticeably absent are any consistent. The index itself is a cry for help. papers dealing with aerosol particles. Some of the topics indexed require two full lines. There is little or no integration of the Many of the book's contributions conbook's sections, and every author seems to tain references to the previous symposium have his or her own index. The layout of the proceedings on the same topic, Particll Size Distributions II, ana other papers pub- index seems to have no plan or organization. lished before 1991—at least a full seven Despite the book's general flaws, it's an years earlier. One would hope that there interesting and fun read. It might be purhave been improvements since then. Refer- chased by scientists involved with the meaences to unpublished symposium proceedsurement and characterization of particles ings, abstracts of contributed (read, not in solution. Some of the articles provide refereed) papers at professional meetings, excellent descriptions of measurement and inaccessible company or private retechniques and their associated instrumenports are of little use to the reader. tation. Many of the articles contain interesting raw data and are well worth skimming. The book presents a dichotomy of apThe book contains some good reviews on proaches by which a particle size distributo the methods proposed, some interesting tion may be obtained: from measurements papers on particle aggregation and modifimade on fractionated samples and from cation, and good introductions to electromeasurements made on unfractionated acoustic techniques. The commercial imsamples. Obtaining the size distribution plementation of phase analysis light scatfrom unfractionated samples generally in552 A

Analytical Chemistry News & Features, August 1, 1999

tering is well described, as are some newer developments with the Honeywell Microtrac device. A lot of discussion about photon correlation spectroscopy methods and their variants fills many of the articles. Another reason to buy the book is its future scarcity. Unlike scientific articles published in first-class journals, these articles are, for the most part, destined to oblivion, because few copies of ACS Symposium Series books are sold, and few major libraries keep them on hand. Reading many of these contributions is both stimulating and interesting, whether one agrees with them or not. In addition, it is so easy to spot the poor papers that little time need be spent on them. Philip J. Wyatt, Wyatt Technology Corporation

A Complete Lesson on Chromatography

Advances in Chromatography, Volume 3 9 Edited by Phyllis R. Brown and Eli Grushka Marcel Dekker, Inc. 270 Madison Ave. New York, NY 10016 1998, 351 pp, $175

Volume 39 of Advances in nhromatography continues J. Calvin Giddings's tradition of helping to convert the art of chromatogra-

phy into the science of chromatography. These seven articles are not simply reviews; they advance our knowledge of separation science and its application. Giddings spent 30 years doing research on field-flow fractionation, the topic of the first section in this volume. He would be pleased to see the physical chemistry of this subject presented in what is very nearly a complete textbook. A few equations still resist direct solution, even by fast computers, but that is to be expected for a technology still in development. All that is known about the quantitative theory of all the subjects in this volume, including particle simulation methods, the analysis of multicomponent chromatograms, the determination of association constants, the selectivity optimization and chemical equilibria in ion chromatography, and simulated moving bed chromatography, has been gathered and arranged in a logical presentation, which progresses from the simple to the complex. This is more of a teaching book than a reference book. The reader will not only use the extensive lists of literature references to find specific data but will also gain an understanding of the principles and quantitative predictability of the techniques discussed Several of the topics in this volume (e.g, selectivity optimization and analysis of multicomponent chromatograms) are familiar to today's chromatographers primarily through the use of commercial computer software. Each of the book's sections serves a very important function by helping chromatographers resist the temptation to let software do the research in "black box" mode. These articles explain what the computer is trying to accomplish, the factors that must be taken into consideration, and how various parameters interact in predictable ways. Because anticipate that an ever-increasing percentage of theoretical knowledge will only be applied through the use of fast computers the articles in this book show that future

aration science will certainly be linked to "components" in the data set other than the advances in computer science. chemicals, such as differences in samples Reviewed by Phillip W. Albro, Trianglecells. It also stressed that these other components need to be included in data sets to Laboratories, Inc. obtain a proper model. Although this may appear to be trivial information, there are experienced spectroscopists who build training data sets that only contain the components of interest, taking great efforts to avoid "impurities" in their calibration samples. For a lot of scientists, it is counter-intuitive to train algorithms with data sets that contain contaminants. The book does a good job of explaining why the creation of data and experimental design is important (e.g., avoiding extrapolation). Several simulated experimental design schemes are used to create data training and validation date sets, ranging from noiseless sets to sets with baselines, nonlinearities, and extra components. The details of the data sets are shown in terms Chemometric Techniques for of the matrix algebra. To keep track of the data files, the book has a crib sheet; unforQuantitative Analysis tunately, the sheet was missing in my Richard Kramer book which made it difficult sometimes Marcel Dekker, Inc. to avoid confusion among the data sets 270 Madison Ave. These date sets are analyzed with several New York, NY 10016 techniques, starting with a clear explanation 1998, 197pp, $99.75 of classical least squares (CLS). A lot of emRichard Kramer has done a remarkable job phasis is placed on the diagnostic tools, and the book discusses the problems associated writing a book for chemists who do not with combining CLS with extra components have a strong background in matrix algethat were not used in the calibration. bra and multivariate analysis. The book takes a "datacentric" approach, focusing The diagnostic tools available for calimore on data and practicalities than on the- brations, such as predicted residual error ory. For example, the Introduction dissum-of-squares (PRESS), standard error of cusses practical problems with data caused calibration (SEC), standard error of predicby factors such as operator influences, tion (SEP), and correlation coefficients are drift, and the use of improper training sets. discussed extensively. Graphic aids for evaluating the calibration, such as plots of The book also provides a very nice inregression coefficients, are also discussed. troduction to matrix algebra; it starts by showing the different conventions of orgaA chapter is devoted to inverse least nizing spectra column-wise or row-wise. squares (ILS). Again, the matrix algebra is Matrices are written out element by elederived in clear steps, which shows why ment, and graphic representations of matri- the number of variables needs to be limces are discussed. The Introduction also ited. Examples with the simulated date sets discusses the possibility that there may be are discussed extensively. The chapter

Quantitative Analysis Made Easy

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