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991.
In this article we have studied the nonlinear interaction between ellipticity and dissipation in a set of model equations (1.1) and established the relation between this interaction and chaos. In addition to theoretical investigations, extensive numerical simulations with these equations have been made, and different routes to chaos have been found. The numerical studies have revealed the chaotic nature of the solutions. 相似文献
992.
An investigation on nonconnectedness of numerical range for monic matrix polynomials L(λ) is undertaking here. The distribution of eigenvalues of L(λ) to the components of numerical range and some other algebraic properties are also presented. 相似文献
993.
A. Hoffknecht O. Uwira A. Frank S. Schennach W. Spies M. Wagner S. Schippers A. Müller R. Becker M. Kleinod N. Angert P.H. Mokler 《Hyperfine Interactions》1998,114(1-4):257-261
The origin of the widely observed enhancement of rates for electron-ion recombination at very low energies is still unknown.
We investigated the recombination of Au25+ with free electrons in a merged-beams experiment at the UNILAC accelerator of the GSI in Darmstadt. At E
rel= 0 eV we found an enormous enhancement factor of 365 compared to the theory of radiative recombination. An increase of the
electron density by a factor of 10 had not much influence on the measured rate coefficient.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
We consider the application of asymptotic methods of nonlinear mechanics (the Krylov-Bogolyubov-Mitropol'skii method) and
the method of separation of motions in nonlinear systems for the construction of an approximate solution of a nonlinear equation
that describes a nonstationary wave process.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 3, pp. 357–371, March, 1998. 相似文献
995.
S. M. Stishov 《JETP Letters》1998,67(1):90-94
Explanations are given for why there is no real first-order phase transition in the one-component plasma (OCP) model. The
fluid (liquid) and crystalline states of the OCP observed in computer experiments are not in equilibrium, on account of instability
of the system. However, specific features of the free energy suggest that some sort of a “virtual” phase transition occurs
in the model. Such a transition can be turned real by choosing the right form of the background energy.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 1, 82–85 (10 January 1997)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
996.
The electronic spectrum of an icosahedral quasicrystal with a central-atom decoration of the Amman-Mackay network is investigated
in the tight-binding approximation. The quasicrystal is described as a structural limit of the optimal cubic approximants
with increasing period. The electronic spectra for the first four optimal cubic approximants do not contain the hierarchical
gap structure which is typical for the Cantor set of the spectrum of a one-dimensional quasicrystal. At the same time, as
the order of the approximant increases, the spectrum becomes singular throughout the entire energy scale.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 8, 557–562 (25 April 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
997.
We show that “top-down” mechanisms of ultrahigh-energy cosmic rays which involve heavy relic particle-like objects predict
a Galactic anisotropy of the highest-energy cosmic rays at the level of minimum ∼ 20%. This anisotropy is large enough to
be either observed or ruled out in the next generation of experiments.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 2, 99–103 (25 July 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
998.
999.
S. Pumplün 《manuscripta mathematica》1998,97(1):93-108
For a Brauer–Severi variety X over a field k of characteristic not two, every symmetric bilinear space over X up to Witt equivalence is defined over k.
Received: 2 February 1998 相似文献
1000.
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