Die Chemische Affinitat (Wiberg, Egon)

It is no exaggeration toexpect that this text will become the. “Bible” of tube engineers ... here or in the cited references. While the material w...
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MAY. 1952 It is no exaggeration to expect that this text will became the "Bible" of tube engineers concerned with the properties of pertinent materials. I t will he the starting point of the quest for information. The answers will, in the majority of cases, be found here or in the cited references. While the material was prepared by a man with extensive experience in the electron tube field, the scope of the cantents extends beyond this field. Experimenters, physicists, chemists, technicians, and teachers in other branches of science can spend many profitable hours with this text. There are 19 chapters whieh discuss seven general topics: glass, structure of solids, metals, ceramics, phase rule, vacuum technique, and thermionic emission. The first six chapters describe the physics of glass, annealing, strain analysis, g l e t o metal seals, electrical conduction, and glhss in radiation fields, respectively. These topics are well chosen and are of great imnortanoe in the tube industrv. However. it is this reviewer's rury, raesium, err., iniread of ilevor~ngalwur 31 per crnr n i rlw trut gl.~ss. The referenreg II.,~ wrw vrvcllvnt vdurnes readily nrnil>tldeon thr sul,jerr of g h ~ owhrrea.; thew I. n nrxrrits of classified information on the other subjects. Chapter 7 presents a review of metallurgical concepts of structures. Methods of analysis such as sections, X-ray and electron diffraction, spectrographic, fractogrephy, crystallography, petrography are listed, in addition to chemical analysis. Space lattices and crystal systems are tabulated. A classifieation of orystals according to the prevailing bond is given. The hand theory of solids is of necessity presented in a brief but meatv .. treatmant. A chapter is devoted to each of the following elements: tungsten, molybdenum, tantalum, nickel, copper, and carbon. Physical, chemical, and electrical properties are given in a manner that is concise but still rather complete. Reactions of oxides and compounds will be of particular interest to chemists. Gas evolution and references to the works of Norton. Marshall. Gulhransen. . h o i thew m:>trrit~l hub and otlwrs will ~ I S Oht. of i ~ ~ r r r r s t F::N one or mow eluwwtrriqtivs lhnr have :wquirrrl lnrtirulnr ignificane6 in the rube hur;int.ss. 'l'hij l e u hring.3 our thrw important qualities, like the crystal structure of tungsten, oxygen content of capper, controlled impurities in nickel, etc. The information is presented in perspectivenot found in other books. Since metals are so important in the vacuum tuhe industry, the author has wisely devoted over one-third of his hook to them. The importance of joining metals by soldering cannot be overemphasized. The material an this subject has been judiciously chosen and clearly presented. Theoretical discussion has been aided by many references to the phase diagrams so indispensable to chemists and metallurgists. A table of solders and brazing materials is given which lists 128 compositions with melting points ranging from 38' to 1966'C. It is regrettable, hut not the fault of the author, of course, that there are so few solders in the 400600°C. and 15004300°C. ranges. Ceramics, mica, and ceramic-metal seals are discussed in two very valuahle chapters. The author has recognized that the use and importance of ceramics has increased rapidly in recent years: "The use of ceramics for tube envelopes has gained in importance over glass since the later is too fragile and has a low softening point. If we add to this enumeration the extensive use of ceramics for circuit components, such as resistors, condensers, transducers, printed circuits, coil forms, etc., there can he little doubt that a. ceramist should he included on the staff of a modern tuhe lahoretory." Rswmateriills, fabrication methods, speoial bodies, applications, and properties are all treated. History and development of ceramic seals is summarized up to the time of publication. Although Gibbs' Phase Rule is well known to chemists Chapter 17 presents a valuable review for them; for one less experienced in this field it provides a. good introduction. The phase rule is useful in the understanding of g l m composition, alloy phases, and the equilibria formed in brazing operations. Data in the chapter on high-vacuum technique pertain to fore pumps, diffusion pumps, greases, waxes, cements, and getters. Most of this infor-

267 mation is presented in tabular farm, which conserves space while at the same time presenting extensive data. A beginner may need the aid of more descriptive texts before obtaining full value from this chapter, however. High lights and recent developments in electron emission are reported in the last chapter. Here again previous experience is necessary for full apppreoiation of the contents. Allusion is made to new materials and developments whieh are to he further explored in the future. These developments include thoria, carbides, borides, oermets, "L" cathodes, and new facts concerning the oxide cathode. In summary, this hook fills a long felt need in the electron-tube industrv. It is a hook that scientists will want to own individually and keep handy for ready reference. Because its stated aim is the scientific treatment of the main solids of electron-tube construction other allied subjects have not been thoroughly covered. Avaluahle companionvolumcmight describe processes,techniques gases, and secondary solids. LEO L CRONIN COPPANT R ~ r ~ a M*NDFAOTDB~N~ ~ o a WALTHAM. MABBACRUB~TB

DIE CHEMISCHE AFFIMTAT Egon Wiberg, Professor of Inorganic Chemistry, University of Co., Berlin, 1951. Munich (Germany). Walter De Bruyter xii 254 DD. 56 fias. 281 eauations and tables. 14 X 22 cm. DM 24..


T m s hook is hased on a course which the author offered as an experiment during the summer of 1950 a t the University of Munich. He tried to explain the problems of chemical affinity and the questions connected therewith to his students by limiting his discussion to the most basic facts and by replacing the abstract with factual evidenoe. To accomplish this he treated the prevailing conception of entropy, for example, as the capacity factor of thermal energy analogous to the concept of the amount of electricity in electrostatics or electrodynamics, or the concept of water volume in hydrostatics or hydrodynamics. Professor Wiberg derserves credit for having had the coursgo to disregard the oonservstism which is so typical of higher education. With his book he has offered factual proof that far more can he accomplished by broadening the scope of our education, instead of making living slide rules or living textbooks out of our younger generation. This book deserves the special attention of every educator who is teaching physical chemistry in the United States. ERNST A . HAUSER

M ~ s s ~ c ~ o s1m ~ s~ns l . mor ~ TBcam~oau AND WOBCEBTER POLYTECBNIC INBTITDTE MA~%ACBUBETTB



Louis Diserens. Translated and revised from the second German edition by Paul Wengrof and Herman P. Baumann. Rein446 pp. 16 hold Publishing Corp., New York, 1951. xii tables. 16 X 23.5om. $12.


THIStext is an extension of the first book, now considered as Volume I, whieh treated vat, sulfur, indigosol, azo, and chrome dyestuffs. The present hook comprises a translation and revision of the remaining important chapter8 of Diserens' "Die neuesten Fortschritte in der Anwendung der Farhstoffe" with newer references added to bring the material up to date. In eight chapters, 6 to 13, the history, theory, technology, and formulas far dyeing and printing substantive and basic dyestuffs, aniline black, and acid dyes are presented; also theuse of various types of dyestuffs in the dyeing and printingof cellulose acetate,