Emulsions: Theory and practice (Becher, Paul) - Journal of Chemical

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by the smaller number of larger suhvolumes which chrtrrtcteriaed the first edition. The present Part C consists of four chrtpters (8 through 11) of Volume 1. These deal with Aldehydes and Ketones (91 pages), by J. G. Buchanan, N. A. Hughes, F. J. MeQuillin and G. A. Swan; Manobasic Carhoxylic Acids (161 pages), by M. F. Ansell and R. H. Gigg; Carhon Monoxide, Isoeyanides and Fulminic Acid (15 pages), by M. F. Ansell; and Ct~rbonicAcid and Its Derivatives (115 pages), by R. Howe. The chapters are adequately organized in the usual way, well documented with both old as well as very recent references, and contain sections dealing with nitrogen and sulfur amlogs of the functional systems discussed. References to specialized texts and review articles are extensive. The volume is completed with a 4&page index to its own contents. No author index is included. The good typography and careful editing characteristic of previous volumes of both editions of Rodd continue in the present one. The principal objection which this reviewer finds to the present volume is its price, whieh seems quite excessive for a mere 382 pages of reference matter, and which (an s. per page basis) proves to be increased almost 9% over that of the recently published Volume I B and almost 23% over that of Volume IA (1964). Libraries will undoubtedly want this volume, but individual chemists, thinking of the probable total cost of the complete revision ($74 for the &st three suhvolumes alone!), may find the rate too steep.

A Labo-

Thin-Layer Chromatography: ratory Handbook

Tbin-Layer Chromatogram (H. Ginshirt); Isotope Techniques (H. K. Mangold); and Theoretical Aspects of ThinLayer Chromatography (M. Brenuer, A. Niederwieser, G. Pataki, and R. Weber). The Special Section is primarily concerned with the application of the method to the resolution, snalysis, and isolation of s wide variety of organic and inorganic materials. This section is divided into the following major topics: Aliphatic Lipids (H. K. Mangold); Terpene Derivatives, Essential Oila, Balsam and Resins (E. Stahl and H. Jork); Vitamins (H. R. Bolliger); Steroids-Sterols; Pregnane-, Androstane-, and Estrane-Compounds; Bile Acids and Cardiac Glycosides (D. Wsldi); Organic Bases (D. Waldi and E. Stahl); Pharmaceutical Products (H. Ginshirt; Thin-Layer Chromatography in Clinical Diagnosis and Pharmacology (D. Wsldi); Synthetic Organic M a t e r i b (H. Giinshirt, D. Waldi, and E. Stahl); Hydrophilic Constituents of Plants (E. Stahl and P. J. Scborn); Amino Acids and Derivatives (M. Brenner, A. Niederwieser and G. Pataki); Nucleic Acids and Nuclwtides (H. K. Mangold); Sugars tlnd Derivatives (E. Stald and U. Kdtenbeeh); Thin-Layer Chromatography of Inorganic Ions (H. Seiler); Spray Reagents for Thin-Layer Chromatography (D. Waldi); Terminology of Thin-Layer Chromatography (English-German-French) (H. K. Mangold and M. Brenner); and Commercial Suppliers. Althoueh the book is nenerallv well primarily because of tremendous advances made in thin-layer techniques in the last few years. One cannot help wondering why a greater effort was not made to update the text in going from the German to the English edition. Also, it seems incongruous that ouly a sketchy treatment was accorded quantitative techniques. Some effort was made, however, to offset the difficulties imposed by rapid advances in technique: an addendum of recent noteworthy articles was included at the end of most chapters.

Edited by Egon Stahl. Academic Press, 553 pp. Inc., New York, 1965. v Figs. and tables. 16 X 23.5 cm. 517.

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The present work represents the English translation of the original handhook compiled by Egon Stahl, which was published over two years ago in German. I t is undoubtedly the most comprehensive and best illustrated of the several hooks on the subject. This volumeshould be viewed as an important reference text for chemical libraries and workers concerned with micromethods of isolation and analysis. Each chapter has been competently written by well-chosen specialists and both theoretical and practicd aspects are knowledgeably and clearly discussed. The book is divided into a General Section and a Specialized Section. The General Section comprises the following major topics: History of the Development of Thin-Layer Chromatography (E. Stahl); Coating Materials for Thin-Layer Chmmetograpby (D. Waldi); Special Techniques (E. Stithl); Dacumentation of Thin-Layer Chromatograms (H. Ginshirt); Quantitative Evaluation of

692 / Journal of Chemical Education

Emulsions:

Theory and Practice

Paul Beckm, Atlas Chemical Industries, Inc., Wilmiugton, Delaware. 2nd ed. ACS Monograph No. 162. Reinhold Publishing Corp., New York, 1965. xi 440 pp. Figs. and tables. 16 X 23.5 cm. $22.

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No one concerned with emulsions whether he he formulating emulsions for commercial use, studying emuhions from the development standpoint, or working on the theory of emulsification, can afford to he without access to this second edition. This edition is almost twice the size of the first edition and has been updated very considerably. The farmet is almost iden-

tical with that of the first edition with the exceution that the former Amendix A on , , mcrla,diof resting has hern r..nvrrt+d inta rr terrninnl chapter, sod the i o m r r Appendix It of cor~mcrwa!lvarnilable emulsifying agents, their trade names and compositions, has been omitted primitrily because it could not be complete within the space limits of the monograph, and secondarily because the field is growing so fast that it would soon he out of date. I t is still true that the formulation of emulsions is partly an art, and only partly a science, but an enormous number of "trich of the trade" are incorporated into the book, and are invaluable to any of the categories of workers mentioned above. The bihliography appears to be very nearly complete and is about twice a? voluminous as that in the first edition. I t include almost all of the important papers of whieh the reviewer is aware, but it would have been helpful if an author index had been provided. The papers cited appear as s series of bibliographies in order of appearance at the end of each chapter so that it is difficult to locate Dr. Becher's evaluation of any given paper. There are ten chaptern. While it i9 true that a, considerable portion of the text of each of these chapters has been repeated verbatim from the first edition, it is also true that the new developments have been incorporated in considerable measure. I t would be very difficult to find the material contained in this monograph without an extensive search of the original literature. Naturally it seems that no book can be written to the complete satisfaction of all readers, w t l rherr YIV a nurnlwr of point> in whivh this book ,runs to be Isvkingfrml intrrrdwl t i e .rxndpuintoi~hci~~rrlriaatc,r in the ha& theory of emdsions. One is the complete lack of any definition of what the author means by the term "stability," no cognizance being taken of the fact that most emulsions are thermodynamically unstable with respect to reversion to the bulk phases. What the author seems to mean by "stability" is a slow rate of reversion to the bulk phases, or a slow separation into a cream or collection of emulsion droplets with a clear, continuous external phase, at the bottom of the containing vessel for O/W emulsions. The distinction between emulsions such as these, which can be restored to their initial st& by mild agitation and those whieh instead undergo irreversible coalescence, is not clearly recognimd. Other omissions of a theoretical nature are the virtual lack of discussion of recent work on the role of the mechanical properties of the emulsifier film in the coalescence process, and of a& tempts to put the HLB number on a sound theoretical basis. Nevertheless, the large collection of factual observations with whichanyone working in this area,needs to be familiar in order to direct his thinking cannot he found easily anywhere else. 811 in all, the reviewer recommends that anyone concerned with emulsions, whether or not he already owns the first edition of this book, acquire the second edition as soon as possible. I t will be a worth while investment.