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81.
M. Petráš 《Czechoslovak Journal of Physics》1995,45(6):455-464
Dirac's and Proca's equations are unified in the sense that the algebras of Dirac -matrices and Duffin-Kemmer-matrices are shown to furnish two distinct matrix representations of the Lie algebra of the SO(3,3)-group. This fact is then interpreted as evidence for the classical picture of particles described by the above-mentioned equations to be a relativistic top. It is also argued that the shape of the top is rod-like. 相似文献
82.
V. B. Popov 《Journal of Mathematical Sciences》1994,70(5):2039-2042
Questions related to the development of a flexible dialogue component automatization system for hightechnology production methods are considered. A formal model of user—system interaction is described. The methods given allow us to approach the problem of the automatization of production of dialogue interactive program packages for SAPR TPP.Translated from Dinamicheskie Sistemy, No. 9, pp. 112–117, 1990. 相似文献
83.
We investigate the one-dimensional, stationary problem of the temperature distribution and rate of plastic deformation in a uniform material under the influence of friction on the surface. The temperature distribution in the material is found by numerically solving the nonlinear heat conduction equation taking into account heat released both at the surface and in the sample interior. We modeled the rate of plastic deformation as a power-law function of temperature. We observed a phenomenon in the solution that might be called a thermal instability wherein stable solution exist only for loads lighter than some critical load. The temperature and plastic deformation distribution have a macroscopic character, and cannot be explained by the formation of a thin, highly deformed surface layer that is usually observed experimentally.Institute of Strength and Materials Research Physics, Russian Academy of Sciences, Siberian Branch. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 23–27, February, 1994. 相似文献
84.
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86.
Spin configuration of Gd13 clusters 总被引:1,自引:0,他引:1
87.
O-Ethyl N-1-adamantylphosphoramidothioate was synthesized and found to fragment on heating in inert solvents to form the pyrophosphate AdNHP(S)(OEt)OP(S)(OEt)OH. The proposed mechanism involves an elimination of the amine portion with release of ethyl metathiophosphate (EtOP(S)O), as was confirmed in previous work for the comparable structure with oxygen. This transient compound then phosphorylates the starting phosphoramidothioate. O-Ethyl N,N-diethylphosphoramidothioate was also synthesized, and while it gave a similar pyro compound on heating, the reaction mixture was more complex. Both phosphoramidothioates, however, served effectively as thiophosphorylating agents toward alcohols, a silanol, and the silanol groups on the surface of silica gel. Exploratory experiments showed that these phosphoramidothioates also could thiophosphorylate the OH group of a monoester of phosphoric acid, as well as that of phosphinic acids, forming anhydrides with the partial structure 相似文献
88.
A new method of mixing sample and reagent due to the difference in their electrophoretic mobilities is introduced. Unlike electrophoretically-mediated microanalysis, sample and reagent are injected from the opposite ends of a capillary tube. This method is compared with electrophoretically-mediated microanalysis. Experiments are performed showing the possibilities of this new method. 相似文献
89.
V. A. Popov 《Journal of Elasticity》1993,30(2):107-121
An asympototic method developed by V.V. Kucherenko and the author is applied to the problem of free vibrations of a thin plate strip in a state of a plane strain. The first few terms of an asymptotic expansion of the natural frequencies are calculated. The results are compared with those obtained by using the classical and refined theories. 相似文献
90.