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201.
A. V. Shapovalov I. V. Shirokov Ya. V. Lisitsyn V. I. Firstov 《Russian Physics Journal》1995,38(2):209-212
D'alambert's equation is used as an example to study the possibilities of a new method of exactly integrating systems of linear differential equations — the method of noncommutative integration (NI). The results confirm that use of the NI is equivalent to complete separation of the variables in the case of four-dimensional subalgebras of conformal algebra. However, the method does simplify determination of the exact solution in this instance.Tomsk University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 120–124, February, 1995. 相似文献
202.
We calculate aPT-odd one-loop meson radiative correction to the scattering amplitude of a nucleon on the external field of the nucleus. The nonrelativistic limit of this amplitude, Fourier transformed to the configuration space, can be interpreted as a single particlePT-odd potential for a valence nucleon. Bound state effects on this potential are evaluated and found to be negligible. 相似文献
203.
The Lie symmetries of nonlinear diffusion equations with convection term are completely described. The Lie ansatzes and exact solutions of a certain nonlinear generalization of the Murray equation are constructed. An example of the family of non-Lie solutions of the Murray equation is given. 相似文献
204.
205.
A new scheme is presented for the physical processes leading to the nuclear fusion reaction d(3He, 4He)p catalyzed by a negatively charged muon μ−. It is shown that the observable rate and yield of the nuclear reaction depend on a chain of ion-molecular reactions involving
the participation of the dμ 3He molecule. New calculations of the nuclear fusion rates in the dμ3He molecule are presented.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 2, 89–94 (25 January 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
206.
We use integrals of Cauchy type and the complex potentials of S. G. Lekhnitskii to solve the problem of the stress-strain
state of a piecewise-homogeneous anisotropic rock during the working of a horizontal seam of mineral. We study the stress
distribution in the deloaded zones. Three figures, 1 table. Bibliography: 4 titles.
Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 27, 1997, pp. 81–86. 相似文献
207.
M. D. Bavizhev V. L. Burlikov V. I. Simanchuk A. V. Kargapol'tsev 《Russian Physics Journal》1991,34(8):727-730
Experimental data on the generation of acoustic radiation in solid targets by pulsed high-energy proton beams are outlined. The features of ultrasound generation in solids by beams of heavy charged particles are analyzed, and the possibility of using the acoustic effect of heavy charged particles to investigate the interaction between radiation and condensed media and to determine particle energies is shown.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 95–99, August, 1991. 相似文献
208.
209.
J. I. Hall 《Combinatorica》1987,7(1):77-85
Within the Johnson schemeI(m, d) we find the graphK(m, d) ofd-subsets of anm-set, two such adjacent when disjoint. Among all connected graphs,K(m, d) is characterized by the isomorphism type of its vertex neighborhoods providedm is sufficiently large compared tod.
Partial support provided by NSF (USA), SERC (UK), ZWO (NL). 相似文献
210.
Mechanisms for the formation of toxisterol A are suggested. The connection between the conformation of the initial previtamin and the stereochemistry of the reaction products is discussed.Lensoviet Leningrad Technological Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 225–229, March–April, 1989. 相似文献