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951.
V. A. Kaganovskii A. S. Plachinda V. M. Chertov L. V. Baksheev V. I. Khromov 《Theoretical and Experimental Chemistry》1987,23(5):596-600
Mössbauer spectroscopy and x-ray phase analysis have been used to examine the structural states and grain sizes of the iron-bearing phase in ferrosilica gels in the initial state and after hydrothermal treatment at 673 K. The component ratio has a substantial effect on the phase composition. The specific surface is also related to the phase composition.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 23, No. 5, pp. 647–651, September–October, 1987. 相似文献
952.
V. G. Kokacheva L. V. Menshikova S. K. Talitskikh P. G. Khalatur 《Journal of Structural Chemistry》1995,36(5):734-738
A system of Ornstein-Zernike integral equations is solved numerically to determine the heats of vaporization ΔHV of liquid ethane, propane, and n-butane. It is shown that the calculations (the deformations of valence bonds and bond angles
in the liquid-phase molecules are ignored) give rather accurate values of ΔHV, which are in agreement with the corresponding experimental data. On the other hand, it is established that if there are
intramolecular rotational degrees of freedom, ΔHV depends on the angle of internal rotation ϕ. The function ΔHV(ϕ) is minimum for trans-conformations (ϕ=0) and maximum for cis-conformations (ϕ=180°). Hence, intermolecular interactions
stabilize compact (convolute) conformations. The energy of this effect is of the order of 1 kJ/mole.
Tver State University. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 5, pp. 808–813, September–October, 1995.
Translated by I. Izvekova 相似文献
953.
954.
The diffusion of copper, nickel and cobalt in silicon single crystals during irradiation with MeV protons, was studied under various experimental conditions. Under the irradiation normally used for charged-particle activation radiation enhanced diffusion negligible. The diffusion of radioisotopes caused by thermal effects however, lead to important errors. It is important to control the temperature of the irradiated samples. 相似文献
955.
Ya. L. Gol'dfarb G. P. Gromova L. I. Belen'kii 《Chemistry of Heterocyclic Compounds》1986,22(6):663-666
Bromination of thiazole by bromine in the presence of aluminum chloride in neutral solvent or without solvent takes place at the 2-position. Such an orientation contradicts the traditional addition-cleavage mechanism, and agrees with the ylid mechanism of electrophilic substitution. 2-Methylthiazole brominates at the 5-position, and the reaction is impeded in the presence of aluminum chloride; this is due to heterocycle deactivation by complexation with the Lewis acid at the nitrogen atom.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 837–840, June, 1986. 相似文献
956.
957.
A. V. Bulatov I. M. Sosonkin A. T. Nikitaev G. A. Kalb M. L. Khidekel' 《Russian Chemical Bulletin》1985,34(5):895-899
Conclusions In the electroreduction of alizarin in an aprotic medium the stepwise formation of the anion-radical and subsequently of the dianion has been observed; under conditions of the prolonged process the anion-radical disproportionates and through intermediate stages of deprotonation and reduction is converted into the stable dianion-radical.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 983–988, May, 1985. 相似文献
958.
959.
A. V. Bobylev N. E. Buyanova A. P. Karnaukhov V. L. Khudyakov N. P. Manyakin 《Reaction Kinetics and Catalysis Letters》1976,5(4):389-394
The systematic and random errors in the determination of the surface area of adsorbents and catalysts by argon thermodesorption chromatography are analyzed.
.相似文献
960.