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Book Review Grundlagen der photographischen Prozesse mit Silberhalogeniden (Principles of Photographic Processes Involving Silver Halides). Edited by H. Frieser G. Haase and E

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gave a 40 % yield of 5,6,7,8-tetraphenyl-1,4-naphthoquinone
( 3 ) (orange crystals, whose formation is most simply explained by cycloaddition of intermediate (2) to tetracyclone and
decarbonylation). Oxidation of ( I ) by lead tetraacetate in the
presence of tetracyclone afforded (3) in 60% yield. / Chem.
Commun. 1969, 647 / -Ma.
[Rd 73 IE]
presumably, the other compounds have covalent XeO bonds.
On the basis of X-ray structure analysis the FXeO group in
FXeOS02F is almost linear, the Xe-F and Xe-0 bond
lengths being 1.94 and 2.16 A resp. and the FXeO angle
being 177.5 '- 0.4O; the XeOS angle is 123.4 0.6". In the
Raman spectra the XeF stretching vibrations were detected
at ca. 500cm-1, the XeO vibrations between 433 and 507
cm-1. / Chem. Commun. 1969, 703 /--HB.
[Rd 77 IEI
-
The adduct BrF3 SbF5 OCCUIS as [BrFz]+ISbF& according
to an X-ray structure analysis carried out by A . J. Edwards
and G. R. Jones. BrFzSbF6 crystallizes orthorhombically in
the space group Pcca with a = 10.12, b = 5.81, and c =
10.95 8, i 0.01 8,; Z = 4. The BrF2+ ion is bent (93.5 ").
the BrF bond lengths having a value of 1.69 8,.The distorted
SbF6 octahedron has four short SbF distances of 1.83 A
( 2 x ) and 1.84 8, (2x). The two remaining F atoms, which are
cis to each other, are bridging atoms to two different BrFz
ions (Sb-F. 1.91 8,; BrF2 . . . F, 2.29 8,; Q B r . . . F-Sb.
153.5 "); the F . . . BrF2 . . . F unit is planar. Cations and
anions combine in this way to form an infinite chain, for
which a purely ionic formulation [BrFz]+[SbF& is only of
limited validity. / J. chem. SOC.(London) A 1969,1467 /-HB.
[Rd 76 IE]
FXeOSOZF, FeXeOCIOj, Xe(OSO2F)2, and Xe(OC103)~
have been prepared by N . Burtlett et al. by reaction of XeF2
with stoichiometric amounts of either HOSOzF or HOClO3
at -110 to -60°C. All the compounds are colorless to pale
yellow; the first three melt at 36.6, 16.5, and 4 3 4 5 " C ,
respectively. Xe(OS02F)Z decomposes into Xe and S206F2
at 20°C; Xe (OC103)2 decomposes in an undefined fashion
into Xe, 0 2 , C1207, and ClOz at -20OC. FXeOSOzF and,
The homogeneous catalyzed H-D-exchange in polycyclic
aromatic compounds using acetic acid as solvent and tetrachloroplatinate(I1) as catalyst has been investigated by R. J .
Hodges and J . L. Garnetf. The rates of exchange are found
to be related to the highest bond order occurring in the molecule: A sharp maximum in the exchange rate is found at a
bond order of about 1.77 (e.g. C-9 H and C-10 H bonds of
phenanthrene). At smaller bond orders the formation of the
x complex ( I ) is rate determining whereas at higher bond
orders the formation of the a complex (2) is rate determining.
Polyphenyls exchange several H atoms during a catalytic
cycle, condensed aromatic compounds exchange only one
H atom. In ortho-condensed aromatic compounds, except
those which contain condensed five-membered rings (e.g.
acenaphthylene), the exchange is hindered. / J. physic. Chem.
73, 1525 (1969) / -Hz.
[Rd 78 IE]
69
BOOK REVIEWS
Grundlagen der photographischen Prozesse mit Silberhalogeniden (Principles of Photographic Processes Involving
Silver Halides). Edited by H. Frieser, G. Huase, and E.
Klein. Vol. 1: Physical and Chemical Properties of Silver
Halides and of Silver; Vol. 2: The Photographic Emulsion
and the Processing of Sensitive Materials; Vol. 3: Photographic Sensitivity. Akademische Verlagsgesellschaft,
Frankfurt/Main, 1968. 1st Edit., 1500 pp., D M 390.-.
When the publications in a large field of research consist
entirely of journal articles and monographs, it is time for
existing knowledge to be gathered into one large work and
presented without ballast.
The authors of the present three-volume work have succeeded
in doing just this, i.e. in presenting more information by
pruning. They have been able to demonstrate experimental
results clearly, to emphasize the problems, and in part even
to provide a retrospective view of the early stages of photography. It is surprising, particularly since the three volumes
extend to a total of 1500 pages, to find that the book is very
up-to-date, the literature being covered in part up to 1967.
It contains almost 5000 references to the original literature or
to other reviews. The Russian and Japanese literature, which
is often treated very sketchily because of language difficulties,
is given due recognition.
Volume 1, by J . Eggers, G . Haase. and R. Matejec, deals
with the physical properties of silver halides and of metallic
silver. The data on structure and bonding, mixed systems
with other metal halides, defects, and crystal dislocations, as
well as on the thermal, mechanical, electrical, and optical
properties, are so comprehensive and up-to-date that they
will often avoid the need for laborious searches in the literature, which is widely scattered in some cases. The chemical
Angew. Chem. internat. Edit. 1 Vol. 8 (1969) J No. 9
properties of silver and its compounds are given less space,
but the treatment is just as detailed.
It is unfortunate that the work is sold only as a set, since the
first volume in particular could be an important reference
book to scientists who are concerned with silver, though not
with photography.
Volume 2, by J. Beersmans, H. Borginon, L. Busch, J. Eggers,
R. Mutejec, R. Meyer, E. Moisar, and M . N . Vrancken, describes the preparation and chemical sensitization of photographic emulsions and their processing. Section 2 (of the
complete work) describes, very briefly but impressively,
gelatin and its properties. In the reviewer's opinion, more
space might have been devoted to this important chapter.
A few lines should perhaps also have been written about
synthetic binders.
Chapter 3 presents an excellent account of the photographic
emulsion and the complex subject of sensitization. The treatment is so skillful that even readers who do not work in this
field should have no difficulty in understanding the material.
No mention is made of the economically important rhodium
effect, on which readily available literature exists.
Chapter 4 consists of three sections on the development of the
photographic emulsion. The theory of development, which is
based mainly on physical concepts, is followed by a section
on the chemistry of the process. This section contains a very
good survey of the most important developing agents known
at present, and color development is also given the attention
it warrants. A more detailed chapter on the Copyrapid
process and on the related Polaroid process would have been
preferred by the reviewer.
Chapter 5 deals with fixing, washing, and stabilization of the
developed silver image. It is regrettable that so little is said
685
about the topical problem of the life of the silver in the image
during storage.
Volume 3, by W. F. Berg, F. Dorr, J . Eggers, C . Hanse, R .
Mfltejec, H . Metz, R . Meyer, E. Moisar, and F. Tomumichel,
presents, in Chapter 6, a review of spectral sensitization by
dyes. After a description of the properties of sensitizing dyes
and of spectrally sensitized emulsions, the two model views of
sensitization, i.e. energy transfer and electron transfer, are
discussed.
Chapter 7 gives an readily understandable description of the
production of a blackening curve, and this is followed by a
long chapter (8) on photographic effects. The two authors in
this section have not only managed to present clearly the
present state of knowledge on the bewildering multiplicity of
photographic effects, but have also traced the literature back
to the early stages of photography, and have thus made a
valuable contribution to the history of scientific photography.
The last chapter (9) is devoted to the latent image and its
formation. The many stages in the formation of a latent
image and the calculation models used for the understanding
of the process are described in detail. From his own overall
view, the author presents a survey that makes it easy for the
reader to understand the relations involved.
This three-volume work will be useful to all who are concerned with the fundamentals of photography in theory or in
W. Buhnmuller [NB 816 IE]
practical research.
Physikalisch-chemische Kristallographie (Physico-chemical
crystallography). By K. Meyer. VEB Deutscher Verlag fur
Grundstoffindustrie, Leipzig 1968. 1st Edit. 337 pp., 225
figures, 69 tables, bound DM 39.80.
Whereas crystal physics and crystal chemistry are normally
treated quite independently in textbooks of crystallography,
with seperate, systematically constructed chapters, the value
of and the need for a complete, systematic discussion of the
typically “physico-chemical” problems of crystallography,
such as crystal formation and transformation, crystal habit
and changes in habit and the many processes and reactions
of and on crystal surfaces (epitaxy, topotaxy corrosion, etc.)
are evidently not yet sufficiently recognized. This is surprising
when one thinks of the importance attached by crystallographers and mineralogists to physico-chemical methods. This
is shown in particular by the test methods used in these two
fields.
K . Meyer’s book probably provides the first systematic treatment, within the scope of a textbook, of the typically “physico-chemical” problems of crystalline materials, in which
both the necessary physico-chemical (particularly thermodynamic) principles and their application to the range of
crystallographic problems mentioned above are presented in
clear, adequate, and neat definitions, formulations, and
derivations. The treatment of the material is always carried
through to the quantitative description and to the latest
position, without the use of excessively demanding mathematics.
The book is fluent, well presented, and always technically
adequate. It is unreservedly successful, and is strongly recommended to all crystallographers, mineralogists, chemists,
physicists, and material scientists. Better paper would have
been preferred for such a good book. The modest price is
insufficient compensation from this point of view.
A . Neuhaus [NB 823 IE]
Die natiirlichen und kiinstlichen Aromen. Zusarnmensetzung
und Herstellung. (Natural and Synthetic Flavors. Composition and Preparation.) By A . M. Burger. Dr. Alfred
Hiithig Verlag, Heidelberg 1968. 3rd Edit., 338pp., 65
figures, plastic cover DM 48.-.
Behind this new, somewhat pretentious title is concealed the
familiar “Buch der Aromen” (Book of Flavors) by the
686
distiller and planter Alfons M. Burger, who died some time
ago in Africa. Dr. J. Hilger of Miinchen has revised the
manuscript, taking the latest knowledge into account. After
the introduction and a short historical section, considerable
space is devoted to the description of the various distillation
processes and the apparatus required for them. Freezedrying, spray-drying, extraction, and other industrial processes used in the commercial production of aroma complexes
are also discussed at some length. This chapter should be
made more concise in future editions, since sufficient firstclass literature on these technological problems is already
available.
This is followed by a section on the chemically definite
aromatic essences, which is necessarily incomplete because
of the very rapid progress that is currently being made in this
field. Nevertheless, it provides a firm foundation for the newcomer. It would have been helpful to practical workers if the
discussion of the individual aromatic essences had been accompanied by some information on their occurrence in
natural products. A short chapter dealing with the different
legal situations concerning the flavoring of foods and beverages in the principal countries would undoubtedly also
have been welcome.
The most useful part to those who work in this field is a section of about 150 pages describing the production of spice
oils, brandy flavors, citrus flavors, and fruit flavors. A simple
formula is always given for the preparation of the corresponding synthetic flavor, though the legal permissibility of the
components used has unfortunately not been considered. The
user should therefore check the legal situation in every case.
After a short discussion of flavors of animal products (honey,
butter, cheese), the book ends with a section on the flavoring
of special products such as baker’s produce, vinegar, confectionery and meat, as well as tobacco. An appendix provides information on solvents and solubilities. Whereas there
are several very good English books, this volume closes a gap
that has existed in the German literature on flavors. It should
be welcomed by interested laymen and practical workers,
and should always be available in the reference libraries of
E. Klein WB 824 IEI
distillers.
Disk-Elektrophorese. Theorie und Praxis der diskontinuierlichen Polyacrylamidgel-Elektrophorese (Disc Electrophoresis. Theory and Practice of Discontinuous Electrophoresis on Polyacrylamide Gel). By H. R. Maurer. W. de
Gruyter und Co., Berlin 1968. 1st Edit. xvi + 221 pp., 82
illustrations, 15 tables, plastic binding, DM 36.-.
Disc electrophoresis, which one connects with the names of
Ornsfein and Davis, is a variant of electrophoresis in polyacrylamide gel and differs from this in that discontinuities
(discs) are set up with respect to pH and pore size within the
separation medium. These cause concentration of the mixture to be separated, which collects as a sharp zone at the
upper end of the column of gel and on subsequent separation
leads to appearance of disc-like zones containing the individual components.
Technical details about the method - known for almost ten
years - and modifications and applications are scattered
through many different publications. It is thus especially
welcome that the author, who has himself contributed several
times to disc electrophoresis. has reviewed the material (602
references) and described the theory and practice of the
method in a n exemplary concise and precise manner. Fourteen gel systems, differing in pH, buffer composition, acrylamide concentration, efc., have been summarized in tabular
form; they should suffice for most problems of separation.
The book is well produced and of convenient form; since it is
aimed at the practice of discontinuous polyacrylamide electrophoresis it should be consulted whenever knowledge is or
should be sought about this technique needing only a minimum of technical equipment. The book is highly recomB. Kickhofen WB 818a IE]
mended.
Angew. Chern. internat. Edit. 1 Vol. 8 (1969) / No. 9
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