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921.
O. A. Éismont 《Fluid Dynamics》1971,6(2):197-202
The convective instability of a layer of conducting liquid carrying a current and lying in a magnetic field perpendicular to the current is considered. The problem of the nonconductive approximation in a linear setting is solved. The relationships between the Rayleigh number and the Hartmann number (determining the neutral stability) are derived.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza. No. 2, pp. 20–26, March–April, 1971. 相似文献
922.
I. Ya. Édel'man 《Fluid Dynamics》1996,31(4):552-559
The propagation of nonlinear waves through a porous medium saturated with a viscous liquid and a gas is investigated with allowance for the capillary pressure. Numerical solutions of the traveling-wave type are constructed for the generalized Korteweg-de Vries-Burgers equation for the wave amplitudes. Three types of regimes of longitudinal wave propagation, including soliton-like regimes, are found.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 86–95, July–August, 1996. 相似文献
923.
L. A. Épshtein 《Fluid Dynamics》1975,10(6):1008-1010
The article sets forth an approximate method for calculating the effect of the walls on the area of the midsection of a plane or axisymmetric cavity, modelled in accordance with the Éfros or Ryabushinskii schemes. For the plane problem, a comparison with the results of an exact solution is given.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 161–163, November–December, 1975.The author takes the occasion to thank A. G. Terent'ev for kindly furnishing his calculations. 相似文献
924.
We investigate the equations of motion of large snow avalanches, and in contrast with [1–3] we take into account the fact that the dry friction can reach a critical value above which the snow in the avalanche or the underlaying material cannot sustain the friction. We find asymptotic solutions for long times after the beginning of motion. These solutions describe the avalanche motion in which a part of the snow moves in the conditions of limiting friction over a tilted plane with a uniform layer of snow. The equations which are used to find these asymptotic solutions have the property that for certain depths the flow velocity of small perturbations decreases with increasing depth. This is related to a number of unusual features (from the hydraulic point of view) of the solutions. In particular, on relatively gentle slopes two zones are formed in the avalanche: the forward part, with a large velocity and thickness of the moving layer, and the rear part, which is significantly slower and thinner. The two parts are separated by a narrow region characterized by a sharp decline in velocity and thickness of the moving layer.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 30–37, September–October, 1977. 相似文献
925.
Dr. Enrico Mugnaioli Dr. José Reyes‐Gasga Prof. Ute Kolb Dr. Joseph Hemmerlé Prof. Étienne F. Brès 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):6849-6852
Herein, we investigate human single hydroxyapatite crystals (enamel and dentine) by convergent‐beam electron diffraction (CBED) and automated electron‐diffraction tomography (ADT). The CBED pattern shows the absence of the mirror plane perpendicular to the c axis leading to the P63 space group instead of the P63/m space group considered for larger‐scale crystals, this is confirmed by ADT. This experimental evidence is of prime importance for understanding the morphogenesis and the architectural organization of calcified tissues. 相似文献
926.
The automodel problem of the motion of a turbulent vortex couple and the transfer of heat by the latter is solved numerically. The singularities of the resultant solutions are analyzed for various rates of change of the turbulent viscosity coefficient.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 21–25, January–February, 1976.In conclusion, the authors wish to thank G. I. Petrov, L. A. Chudov, and the participants of their seminar for discussions of the work involved. 相似文献
927.
928.
JPC – Journal of Planar Chromatography – Modern TLC - Plant resistance breeding has, so far, been based on specific resistance genes which regulate hypersensitive reaction, resulting in... 相似文献
929.
A. V. Shaposhnikov D. V. Gritsenko I. P. Petrenko O. P. Pchelyakov V. A. Gritsenko S. B. Érenburg N. V. Bausk A. M. Badalyan Yu. V. Shubin T. P. Smirnova H. Wong C. W. Kim 《Journal of Experimental and Theoretical Physics》2006,102(5):799-809
The atomic structure of amorphous and crystalline zirconium dioxide (ZrO2) films is studied using X-ray diffraction and extended X-ray absorption fine structure techniques. The electron structure of ZrO2 is experimentally determined using X-ray and UV photoelectron spectroscopy, and the electron energy band structure is theoretically calculated using electron density functional method. According to these data, the valence band of ZrO2 consists of three subbands separated by an ionic gap. The upper subband is formed by the O2p states and Zr4d states; the medium subband is formed by the O2s states; and the narrow lower subband is formed predominantly by the Zr4p states. The bandgap width in amorphous ZrO2, as determined using the electron energy loss spectroscopy data, amounts to 4.7 eV. The electron band structure calculations performed for a cubic ZrO2 phase point to the existence of both light (0.3m 0) and heavy (3.5m 0) holes, where m 0 is the free electron mass. The effective masses of band electrons in ZrO2 fall within (0.6–2.0)m 0. 相似文献
930.