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991.
On the basis of exactly solvable stationary models for the Schrödinger equation, we develop a procedure for solving the nonstationary Schödinger equation in an explicit analytic form. We investigate the formation of the nonadiabatic geometric phase during cyclic evolution of a quantum system. 相似文献
992.
Foda Omar Leclerc Bernard Okado Masato Thibon Jean-Yves Welsh Trevor A. 《Letters in Mathematical Physics》1998,43(1):31-42
A special family of partitions occurs in two apparently unrelated contexts: the evaluation of one-dimensional configuration sums of certain RSOS models, and the modular representation theory of symmetric groups or their Hecke algebras Hm. We provide an explanation of this coincidence by showing how the irreducible Hm-modules which remain irreducible under restriction to Hm_1 (Jantzen–Seitz modules) can be determined from the decomposition of a tensor product of representations sln. 相似文献
993.
Mass distributions of fragments in the low-energy fission of nuclei from 187Ir to 213At have been analysed. This analysis has shown that shell effects in symmetric-mode fragment mass yields from the fission of pre-actinide nuclei could be described if one assumes the existence of two strongly deformed neutron shells in the arising fragments with neutron numbers N1 ≈ 52 and N2 ≈ 68. A new method has been proposed for quantitatively describing the mass distributions of the symmetric fission mode for pre-actinides with A ≈ 180–220. 相似文献
994.
We show that, contrary to earlier reports, application of the one-parameter variational technique to the classical (image) model for H in front of an Al surface leads to energy shifts for the ground state which are very close to those obtained numerically with a more sophisticated model of the system. 相似文献
995.
996.
We review data on methods for synthesis, chemical and pharmacological properties of pyrido[1,2-a)pyrimidines.Scientific-Research Institute of Pharmacology of the Russian Academy of Medical Sciences, All-Union Science Center for Biologically Active Substances, Staraya Kupavna, 124432. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 579–596, May, 1994. Original article submitted March 3, 1994. 相似文献
997.
998.
999.
1000.
A. A. Bormisov E. S. Gudkova F. Kh. Mukminov 《Theoretical and Mathematical Physics》1997,113(2):1418-1430
We consider equations of the form Uxy = U * Ux, where U(x, y) is a function taking values in an arbitrary finite-dimensional algebra T over the field ℂ. We show that every
such equation can be naturally associated with two characteristic Lie algebras, Lx and Ly. We define the notion of a ℤ-graded Lie algebraB corresponding to a given equation. We prove that for every equation under consideration, the corresponding algebraB can be taken as a direct sum of the vector spaces Lx and Ly if we define the commutators of the elements from Lx and Ly by means of the zero-curvature relations. Assuming that the algebra T has no left ideals, we classify the equations of the
specified type associated with the finite-dimensional characteristic Lie algebras Lx and Ly. All of these equations are Darboux-integrable.
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 113, No. 2, pp. 261–275, November, 1997. 相似文献