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On the Chemistry of Amphoteric Oxides.

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uniformity in the degree of chlorination as possible explanations may be excluded. It is probable that products are
formed during the chlorination in gels with great differences
in the lengths of the sequences of the three basic structural
units.
Elucidation o f the Microstructure of Polymers by
Nuclear Magnetic Resonance Specrroscopy
U. Johnsen, Darmstadt (Germany)
The proton resonance spectra of vinyl polymers with a
simple cc-substituent are much easier to analyse when the
coupling between the a- and @-protonsis cancelled by double
resonance. This method was used t o elucidate the microstructures of some poly(viny1 chlorides).
The spectra reveal that o n chlorination of PVC, the methylene
groups are substituted with three to four times higher
probability than the chloromethylene groups. I n addition t o
non-chlorinated monomer units, the chains contain only the
structural units -(CHCI-CHCI)and -(CCI~-CHZ)-. The
frequency of recurrence of these structural units, the average
lengths of uniform blocks made UD of these units. and the
chlorine contents of the products studied were determined.
KGa02 is the first compound of the KFeO2 structure-family
with a proven structure. According to powder photographs
this family includes the cubic or pseudocubic compounds
KFeOz (a = 7.958 8)111, RbFeO2 (a = 8.10 A) [2], CsFeO2
(a = 8.32 8)[21, KAlO2 (a = 7.79 A) 131, RbAlO2 (a =
7.73 A) [41, CsA102 (d = 8.10 A) [4], RbGa02 (rhombic,
a = 5.64 A, b = 11.37 A, c = 16.19 A, isotypic with KGa02)
141, CsGaO2 (rhombic, a = 5.83 A, b = 11.68 A, c = 16.50 A,
perhaps isotypic with KGa02, possibly also cubic with
a = 16.50 A) [41, and, according to single-crystal investigations, the cubic CsScOz (a = 17.45 A) [4]. As already supposed from powder photographs these compounds have a
“filled framework structure” of the $-cristobalite type.
Distances for K G a 0 2 : Ga-0 = 1.68-1.95 8 ( 4 x ) ; K - 0 =
2.53-3.52
A
(8x).
NaGaO2 [51 occurs as two modifications; the low-temperature form (a) is of the B-NaFe02 type according to
single-crystal investigations, and is a variant of the wurtzitetype. The rhombic unit cell with a = 5.301 A, b = 5.519 A,
c = 7.201 A, space group CZv-P2lnb, contains four formula
units; all particles occupy the equivalent positions 4 (a), with
the parameters:
l x
[VB 910/228 IE)
Na
Ga
German sersion: Angew. Chem. 77. 509 (1965)
01
0 2
0.240
0.746
(0.81)
0.418
I -B
I y
0.410
0.061
0.395
0.060
0.126
0.123
0.173
0.102
2.70
1.05
1.70
1.60
On the Chemistry of Amphoteric Oxides
R. Hoppe, Miinster (Germany)
Amphoteric metal oxides can react with “acidic” non-metal
oxides [e.g. T I 2 0 3
3 SO3 + Tl~(S04)3] as well as with
“basic” metal oxides [ e . g . TI203 + NazO -f 2 NaT1021.
Little has been reported on ternary oxides of the alkali metals
which, like NaT102, belong to the second group of compounds.
+
Many new oxides have been prepared which, according to
their crystal structure, represent transitions between the
extreme types“mixed oxide” and ‘‘0x0 complex”. Of these, the
following are noteworthy:
The previously unknown oxogallates KGa02, RbGaOz, and
CsGaO2 were prepared at 400-450 ”C in 20-24 hours under
dry nitrogen, e.g.
2 CsO1.25
+ Ga203
+ 2 CsGaOz
They are colorless powders and extremely sensitive to moisture. The crystal structure of KGaO2 was determinedon
single-crystals using Fourier methods. KGaOZ crystallizes
pseudocubic, orthorhonibic with a = 5.515 A, b = 11.076 8,
and c = 15.818 A, with Z = 16 formula units per unit cell
Idx-ray = 3.87 and dpyk = 3.78 g.cm-31 in the space group
D:;-Pbca. All particles occupy the equivalent position 8 (c)
with the following provisional parameters:
X
Y
2
-B
0.260
0.279
0.749
0.008
0.189
0.065
0.062
0.186
0.014
0.100
0.59
0.68
1.71
1.12
0.796
0.578
0.170
0.286
0.905
0.264
0.014
0.264
0.298
0.404
0.173
0.479
0.155
0.224
C. Boron, Djjon (France)
Preparative, enzymological, and physiological investigations
of two liver enzymes were discussed. These enzymes play
a role in the metabolism of healthy and cancerous cells which
has but little been studied. They are catalase, an otherwise
well-investigated enzyme, and amine oxidase, of the properties of which relatively little is known.
As catalase has a healing effect on skin injuries, experiments
with artificially (by calcium triphosphate) produced granulomas were performed. Catalase caused intensive fibroblast
proliferation and the formation of collagen fibres.
The enzyme preparations were crystalline catalase and less
pure amine oxidase preparations. This second enzyme is
firmly attached to mitochondria and thus difficult to enrich.
Detergents, especially a 0.2 %, solution of sodium lauryl
sulfate at p H 7 and 20 OC, proved most effective in loosening
this attachment. In this way, it was possibIe to bring into
solution about 30 of the enzyme, without loss of activity,
in the first step, and a further 20 % in the second step. The
preparations were free from diamine oxidase activity.
2.46
0.46
1.75
2.77
Of 976 possible reflections (Okl) to (4kl), 663 have been
observed; Mo-K, radiation; I, determined photometrically
from “integrated” Weissenberg photographs, R = 0.153 and
R‘ = 0.25.
534
Recent Investigations on Oxidases and Peroxidases
[ I ] S . Hilpert and A . Lindner, Z. physik. Chern. B 22, 395 (1933).
[2] C.-J. Brendel, G. Wehrmeyer, and W. Klemm, unpublished
work; cf. G. Wehrmeyer, Ph. D. Thesis, Universitat Miinster 1959.
[3] L . T . Brownmiller, Amer. J. Sci. 29, 260 (1935); T. F. W.
Earth, J. chem. Physics 3, 323 (1935).
[4] Author’s own investigations.
[ S ] Recently prepared by B. N . Ivanov-Emin and J . I . Rabovik,
Zhur. obshch. Khim. 17, 1061 (1947).
Angew. C h m . internut. Edit.
Vol. 4 (1965) 1 No. 6
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