Elements of ordinary differential equations

polymers, plus a new chapter on mechanical properties. It is in these four fields that much of the work of the last ten years has been concentrated; i...
0 downloads 0 Views 1MB Size
NOVEMBER, 1950 mize on space, several subjects (for example, X-rays, electrical and light scattering) are treated mostly from the fundamental rather than the applied point of view, although references are given to review srticles. Industrial readers will probably welcome the convenience of having this fundamental physical chemistry in a reference book on polymers; academic readers, on the other hand, possibly would prefer to have the general material covered by reference and to see more details of applications to polymeric systems. The second half of the book is an expansion from 128 to 242 pages on the thermodynamics, hydrodynamics, and kinetics of polymers, plus a new chapter on mechanical properties. I t is in these four fields that much of the work of the last ten years has been concentrated; it is natural, therefore, to expoot a considerable increase in the space devoted to them. Our present understanding of thermodynnmics and hydrodynamics of polymer solutions represents a tremendous advance over tho status of these ten years ago; the authors present in a very readable style an outline of this work, with an exrellent bibliography. The section on mechanical properties is a review of clsssical theory, followed by a summary of the recent significant work from the Princeton laboratories. In kinetics, copolymeriaation (st best, a beginning art ten years ago), redox system, absolute reaction rat&, emhlsion polymerization, and chain transfer are all modern subjects which are carefully summarised, along with the previous material. The book is warmlv recommended to all research workem in the field of polymers. It is essentially a reference and aonrce book rather than a text hook: the field is now so brosd that m n y detailils of derivation and procedure were of necessity omitted, as the authors state in their preface. RAYMOND M. FUOSS

INTRODUCTION TO PLANT BIOCHh'MISTRY Catherine C. Steele, M.A., BSo., Ph.D. St. Andrews, sometime ledurer in chemistry at the Horticultural College, Swanley, Kent. Second revised edition. G. Bell & Sons. Ltd., London. 1949. viii 346 pp. 12 figs. 6 tables. 14.5 X 22 cm. 22/6d.

+

T m s book, a revision of that published in 1934, is designed to pmvide the botany student ". . .with an introductory account of the chemical nature and relationships of the substances elahorated by plants." The book is divided into seven sections. The first deals with the colloidal state and chemical composition of plants. The next five sections survey the kinds of organic compounds found in plants: 11, alcohols, fatty acids, fats, and oils; 111, aldehydes, ketones, and carbohydrates; IV, plant acids; V, proteins and related compounds; VI, cyclic compounds. Each subject is introduced by a. consideration of the general organio chemistry and properties of the compounds. This is followed by a short treatment of the hiogenesis and physiological function of the eompounds as plant metabolites. The author often offers interesting notions on the function of these compounds, examples of which are: "[glycosidesl. . perform a biologicsl fundon in protecting the plant from raids by animals.. . " and "[fat synthesis]. . plays sn important part in the defence mechanism of the plent against low temperatures." However, as a general s u m y of plant products the fimt six sections of the book will be found useful, although some of the subjects such as the pectins receive a very brief treatment in spite of the wealth of information that has itccumul~tedsince 1934. The seventh section, Plant Metabolism, is subdivided into chapters on eneymes, photosynthesis, respiration, nitrogen metab o h m , plant growth, and fmit ripening. Unfortunately, lack of clarity and general sketchiness serve to detract greatly from what might have been the most useful part of the book. The chapter on respiration is particularly disappointing because of the failure to provide the student with a clear and precise picture of the biochemiesl mechanisms involved in respiration and fermentation. Thus, the citric acid oyde isdismissed with one page and sum-

marized by the statement that ". . . isocitric acid is the most oxidizable substance in the cycle and experiments indicate that h a 1 oxidation to carbon dioxide and water ocour a t this point." The chapter on plant growth suffers from the author's apparent unfamiliaritv with the literature an the hormonal control of ~ l a n t maize germ oil. S.

Q. WILDMAN

CALIFORNIA I R ~ T I T OOP T ~T ~ E N O L O O I

P * a ~ o e ~ aC~u.laonrna .

ELEMENTS OF ORDINARY DIFFERENTIAL EQUATIONS Michael Golomb, Associate Professor of Mathematics, Purdue University; and Merrill Shonks, Associate Professor of Mathe. matics and Aeronautical Engineering, Pmdue University. First Edition. International Series in Pure and Applied Mathematics, Consulting Editor: William Ted Martin. MeGraw-Hill B w k Company. New York. 1950. ix 356 pp. 49 figs. 16 X 24 cm. $3.50.

+

To quote from the preface: "This text is intended for use in s first course in ordinary differential equations and is written for students who have had hut a year's course in elementmy calculus. It is designed to appeal to studenta majoring in engineering, science, or mathematics." The book opens with a chapter devoted to a review (and collection of formulas) of such a first course in calculus. The remaining chapters of the book are based on this chapter in such a way that it is apparent that the first o b jective has been well attained. The authors are in the Mathematics and Aeronautical Engineering Departments of Purdue University. The result of their combined effortsis a b w k which mixes in an admirable fashion the demands for logic and rigor of a mathematician and the practical ideas of an engineer. The reader is introduced to the concepts of differential equetions by means of geometric interpretations. Various types of differential equations are solved by methods suggestive of general procedures. The use of special rules and formulas is avoided. Operator notation is introduced and the operational methods are discussed in a logical fashion. Later, various special equations srre discussed. The authors are to be commended for the introduction of a chapter devoted to the discussion of Bessel functious, Legendre polynomials, hypergeometric functions, and various other related subjects not usually discussed in such a book. The procedures me well illustrated by the inclusion of many examples. These examples are well chosen as problems which are often met in theoretical physics and related fields. The examples themselves will form a useful reference collection for the student. Many problems for the readw, with answers, m e provided.

ELECTRONIC MECHANISMS OF REACTIONS

ORGANIC

Allon R. Day, Associate Professor of Organic Chemimky, Uni-' versity of Pennsylvania, Philadelphia, Pennsylvania. America. Book Company, New York, 1950. 314 pp. 15 X 2 3 em. $3.50. THIS book is an outgrowth of a course developed by Professor Day for advanced undergraduate and beginning graduate students. Its expressed purpose is to systematize the study of organic chemistry through the use of electronic mechanism. There a x thirty chapters ranging from two pages in length (alkane hydrocarbons) to twenty-nine pages (carboxylio acids and derivatives). The electronic interpretations of the wellknown reactions for each elass of compounds are taken up in an orderly fashion. The treatment is entirely qualitative, and i a