Surface and colloid science, vol. 9

Book Reviews Surface and Colloid Science, Vol. 9. Edited by EGON MATIJEVIt~, Wiley (Interscience), New York, 1976, 382 pp. $34.95. Surface and Colloid Science, Volume 9, edited by Egon Matijevic is the latest in the open ended series on the chemistry, physics and technology of colloid systems. The present volume contains four chapters, three dealing with various aspects of emulsions and micelles and a fourth on gas-solid adsorption phenomena. The overall quality of the publication is high and well-edited with very few typographical errors. The lack of coherence among the various chapters is a problem this series has had from the beginning, and although this was recognized by the editor, one wishes there was some way to surmount the problem. The first chapter is entitled "The Stability of Emulsions and Mechanisms of Emulsion Breakdown" by B. J. Carroll. This is an interesting article which has its stated purpose to "set out the present state of the theory and . . . the technology of the stabilization and destabilization of emulsions." It does neither of these very well but does outline in a very qualitative and conversational manner the factors involved in the theory and investigation of emulsion stability. It is neither an authorative nor a critical review in the sense or spirit of the Surface and Colloid Science series. It discusses in general terms the phenomena of flocculation and coagulation with emphasis on the Derjaguin-Landau-Verwey-Overbeek theory and modifications thereof. The coalescence process is discussed with reference to several experimental techniques including ultracentrifuge studies, thin film studies and temperature dependent studies among others. The section on the breakdown of emulsions lists and comments on several techniques for inducing breakdown including electrolyte addition, heterocoalescence, reduction in film elasticity, mass transport of a surfactant between droplets and surfactant control, elastic and magnetic field effects and third body effects. Again the treatment is general and conversational. The bibliography contains 300 references, about one-third of which are post-1970. The second chapter "Nuclear Magnetic Resonance of Surfactant Solutions" by T. Nakagawa and F. Tokiwa is a well written review of the manner in which chemical shift and relaxation parameters can be used to explore the structural and dynamic aspects of micelles, mixed micelles and emulsions. The authors expeditiously draw from a large body of studies in the literature to demonstrate the type of questions 0021-9797/78/0631-0174502.00/0 Copyright © 1978 by Academic Press, Inc. All fights of reproduction in any form reserved.

NMR studies can be directed towards. Only passing mention is given to 13C-Fourier transform NMR. A useful bibliography is included. Chapter three by D. G. Schmidt and T. A. J. Payens on "Micellar Aspects of Casein" is a most interesting article. It is written in an expository manner leading from the colloidal and structural properties of casein micelles to the characterization and study of the properties of the component proteins, to the organization of these components in the micelle assembly. The authors discuss a variety of experimental techniques for studying micellar systems and in particular casein micelles and point out some of the weakness of the methods and emphasize caution in the interpretation of data. By far the most comprehensive of the review chapt e r s is "The Adsorption of Gases on Porous Solids" by S. J. Gregg and K. S. W. Sing. The coverage is very broad including not only the adsorption on porous solids but on nonporous solids as well. Ample space is devoted to discussion of surface forces, adsorption thermodynamics and theories of isotherms, the distinction between adsorption in micropores versus mesopores, the Kelvin equation and its application and misapplication to the determination of pore size distributions, a fine discussion and comparison of the Dubinin-Radushkevich and the Langmuir equations, and detailed description of the use of the t-plot and a-plot as standard isotherms. There was some disappointment of my part in the discussion of hysteresis. This may be more a result of the state of science rather than treatment of the phenomena by Gregg and Sing. There are, however, a few points which left me with an uneasy feeling. Figure 20 purports to be a plot of "chemical potential" versus "distance from wall of capillary." The figure is used to explain the necessity of the Derjaguin correction to the Kelvin equation and is taken from the Everett and Haynes Specialist Periodical Reports in Colloid Science. The reader is urged to refer to them for a proper explanation of the figure and its import. Professor Sing's recent reviews in Volume 1 and 2 of the Specialist Periodical Report in Colloid Science along with the chapter in the present volume constitute important and very useful contributions and critiques of the area of gas-solid interactions. ROBERT A. PIEROTTI

School of Chemistry Georgia Institute of Technology Atlanta, Georgia 30332 174 Journal of Colloid and Interface Science, Vol. 63, No. 1, January 1978