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Book Review Electrochemische Stromerzeugung (Electrochemical Production of Current). By F. von Sturm

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of the class Blg is not available for calculation of force
constants in the case of SZNZ.since the substance is too unstable to furnish interpretable spectra. / J. chem. Physics 51,
268 (1969) / -Hz.
[Rd 99 IE]
electronic conductivity predominates in the whole range of
temperatures investigated. Similar studies were carried out
with CuCN, AgCN. AuCN. Trans. Faraday SOC.65,1912,
1920 (1969) /-&.
[Rd 100 IE]
The electrical conductivity of CuCl at high pressure, as determined for tablets at 370-670 “K and 10-55 kbar is reported
by R. S. Bradley, D . C. Munroe, and P. N . Spencer. A plot of
the logarithm of the conductivity against l / T at constant
pressure is a straight line which changes its slope at 220 20 “C. The slope, which can be regarded as a measure of the
activation energy of the conduction process, falls in the low
temperature range and rises in the high temperature region
with increasing pressure, from which it may be concluded
that electronic conduction predominates at lower temperatures and ionic conduction at higher temperatures. Doping
with CdC12 up to 1 mole-% has little effect on the conductivity; doping with CuCIz, on the other hand, causes a considerable increase in the conductivity; at higher pressures (40 kbar)
Solvent effects in the fluorescence and phosphorescence of
indole are discussed by C. M . Chopin and J. H . Wharton.
The relative quantum yields for fluorescence and phosphorescence change considerably on going from nonpolar to polar
solvents, without any corresponding changes becoming apparent in the absorption spectrum. The authors assume,
deviating from earlier interpretations, that isomerization
from the first excited singlet state of indole to the corresponding state of 2H-indole can take place relatively easily; the
triplet states of the two molecules also lie at very similar
energies. Varying solvent stabilization of the excited states
then affords a ready explanation of the observed anomalies
in the emission spectra. ’ Chem. Physics Letters 3 , 552 (1969) ’
-HZ.
[Rd 101 IE]
BOOK REVIEWS
Electrochernische Strornerzeugung (Electrochemical Production of Current). By F. von Sturm. Vol. 5 of “Chemische
Taschenbiicher”, edited by W . Foerst and H . Grunewald.
Verlag Chemie GmbH, Weinheim/Bergstrasse 1969. 1st
Edit., ix 189 pp., 83 illustrations, paper DM. 16.-.
+
The direct conversion of chemical into electrical energy has
aroused much interest in the last decade because of the
manifold requirements of our present technology and civilization. Although the thermodynamic and technical advantages of this type of energy production have been general
knowledge for a very long time. there are still great difficulties
preventing its realization in an economically rational manner.
This has stimulated research into the use of new methods
intended to supplement the classical established systems
for conversion of electrochemical energy or to replace them
by more efficient systems.
The pocketbook under review gives an excellent introduction
to this type of problem. It begins with a brief sketch of the
mode of action, construction, and limitations of classical
primary and secondary batteries; this section also treats
modern, alternative systems for such purposes. The main
weight, however, is placed on the problems of fuel cells
(about 2/3 of the text); the author attempts to delineate the
trend of their development, placing the main emphasis on
successful methods but without forgetting interesting sidelines even when there is no present prospect of their realization.
The presentation is clear and stimulating, and this well
written introduction can be very warmly recommended.
H . Gerischer [NB 838 IE]
Statistische Elektrizitat als Gefahr (The Dangers of Static
Electricity). By K. Haase. Verlag Chemie GmbH., Weinheim/Bergstr. 1967. 1st Edit., 124 pp., 21 illustrations,
DM 14.-.
Most of us have at one time or another picked up a static
charge from a modern floor-covering, and were unpleasantly
surprised by the resulting powerful sparks. Some of us may
also have tried to use this phenomenon to ignite a gas burner
or perhaps ether, and have found that this technique works
a11 too readily.
Static may be encountered in industry with transmission belts
and with spinning machines. Pneumatically conveyed materiAngew. Chem. internat. Edit. f Vol. 8 (1969)
1 No. 10
als can collect a high charge, as can insulating dusts on drying
and unloading. Static electricity also builds up whenever
insulating liquids or gases leave grounded equipment. It is
therefore laudable that K. Haase should have written this
readily understandable book on the dangers of static, a book
that will be welcomed especially by process engineers and by
those concerned with the design of new production plant.
The first section, occupying about a third of the book, describes the physical principles: electrostatics, charging up by
charge separation, physics of the ignition of explosive mixtures. The second section deals with measurement techniques,
including some specific methods of measurement for floors,
shoe soles, and drive belts. In the last two sections the author
discusses the ways of eliminating static electricity as a source
of danger. This part is illustrated by 19 practical examples.
The book ends with a bibliography, a formula index, and an
K. J. Euler [NB 817 IE]
alphabetical index.
Dreiringe rnit zwei Heteroatomen. Oxaziridine - Diaziridine Cyclische Diazoverbindungen (Three-membered Rings
containing Two Hetero Atoms. Oxaziridines, Diaziridines.
Cyclic Diazo Compounds). By E. Schmitz. Vol. 9 in the
series “Organische Chemie in Einzeldarstellungen”.
Springer-Verlag, Berlin-Heidelberg-New York 1967. 1st
Edit., xii + 179pp., 5 illustr., bound DM 58.- / S 14.50.
Since three-membered rings containing two hetero atoms
were first synthesized in the 1950’s, this monograph treats a
very young area of organic chemistry, one, by the way, to
whose rapid development the author has himself contributed
decisive material. It is true that nitrones, hydrazones, diazomethane, and certain peroxides were earlier formulated as
three-membered ring compounds, but all such structures
were finally abandoned in favor of acyclic ones.
Each chapter is developed in accord with the historical course
of discovery of its three-membered ring system. Treatment
begins with the oxaziridines, the proof of whose structure was
so important because, after a whole series of faulty interpretations, this provided the first certain occurrence of a
three-membered hetero ring system. Oxaziridines are among
the strongest organic oxidizing agents although they are
themselves oxidized by peracids, a reaction from which an
elegant synthesis of nitrosoalkanes in good yield has been
developed.
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