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871.
I. N. Ivchenko S. K. Loyalka R. V. Tompson 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2002,25(6):58-72
The slip phenomena in gas mixtures are of fundamental significance in the specification of boundary conditions for flows in the slip regime. In a recent paper, new explicit results for the slip coefficients appropriate to binary gas mixtures were reported. The present work being reported extends the previous work to a higher level of accuracy by involving a higher order Chapman-Enskog expansion. In particular, new expressions for the slip coefficients are presented which are applicable for arbitrary models of the intermolecular interaction. Limiting expressions for the slip coefficients are given (for a simple gas) and the accuracy of the theory is discussed. Numerical calculations of the slip coefficients for different binary gas mixtures using the first and second order Chapman-Enskog approximations and the rigid sphere and Lennard-Jones (12-6) potential models have been carried out. The thermal creep and diffusion slip coefficients are found to be sensitive to the order of the approximation and to the potential model used. A comparison of the new higher order results with some of our previously obtained experimental data for the thermal transpiration effect has also been carried out and shows excellent agreement between the theory and the experiments which confirms the accuracy of the theory. 相似文献
872.
873.
874.
V. I. Khromov V. V. Kharlamov A. M. Chekmarev G. A. Andropova B. A. Mamet A. S. Plachinda 《Hyperfine Interactions》1991,67(1-4):565-567
The iron containing corrosion products from water heat-carrier and deposits of the second circuit of the nuclear power plant were investigated by means of absorption Mössbauer spectroscopy. The nonstoichiometric magnetite and paramagnetic (superparamagnetic) iron oxide particles were found to be the main corrosion products. The fraction of the magnetically ordered phase varied in the range 0–100% depending on the location in the second circuit. 相似文献
875.
A study is made of the laws governing high-temperature creep and the evolution of the substructure in dispersion-hardened
alloy Ni — 3 vol. % HfO2 during its free annealing and creep. The polygonized substructure was formed in the alloy prior to annealing. An analysis
is made of structural transformations at different structural levels and the mechanism of high-temperature creep in the alloy.
Institute of the Physics of Strength and Materials Science, Siberian Branch of the Russian Academy of Sciences. All-Republic
Engineering-Technical Center, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 3, pp. 83–89, March, 1998. 相似文献
876.
877.
878.
879.
M. V. Patrakeev A. A. Lakhtin I. A. Leonidov A. V. Nikolaev V. L. Kozhevnikov 《Ionics》1997,3(1-2):89-95
A heat machine is studied of regenerative type, based on solid electrolytes with unipolar oxygen conductivity. The achieved
specific power is about 0.2 mW/cm2. Electrical characteristics are derived as a function of temperature, pressure and gas composition in the working chamber
of the converter. Factors which influence the specific power as well as optimal regimes for the functioning of the device
are determined. 相似文献
880.
D. I. Moldavanskii 《Ukrainian Mathematical Journal》1991,43(12):1569-1571
Necessary and sufficient conditions for the isomorphism of two groups, each defined by a single relation of the type a–1bma=bn, are obtained.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 12, pp. 1684–1686, December, 1991. 相似文献