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911.
Vladimir V. Vershinin 《Acta Appl Math》2003,75(1-3):281-292
Malcev–Poisson structure on a manifold is analogous to a Poisson structure with the Lie identity replaced by a slightly more general Malcev identity. Examples of such structures arise naturally. In the second part of the paper we study Malcev bialgebras. A theorem of characterization is proved. 相似文献
912.
I. V. Denisova O. A. Ladyzhenskaya G. A. Seregin N. N. Uraltseva E. V. Frolova 《Journal of Mathematical Sciences》2005,130(4):4775-4779
Bibliography: 42 titles.__________Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 306, 2003, pp. 7–15. 相似文献
913.
A. A. Rajabi 《Few-Body Systems》2005,37(4):197-213
A mathematical method is presented for solving the Schr?dinger equation for a system of identical body forces. The N-body forces are more easily introduced and treated within the hyperspherical harmonics. The problem of the N-body potential has been used at the level of both classical and quantum mechanics.
The hypercentral interacting potential is assumed to depend on the hyperradius x = (ξ12 + ξ22 + ⋯ + ξN−12)1/2 only, where ξ1,ξ2,…,ξN−1 are Jacobi relative coordinates which are functions of N-particle relative positions r12,r23,…,rN1. The problem of the harmonic oscillator and the Coulomb-type potential has been widely studied in different contexts.
Using the N-body potential V(x) = ax2 + bx − (c/x) as an example, and assuming an ansatz for the eigenfunction, an exact analytical solution of the Schr?dinger equation for
an N-body system in three dimensions is obtained. This method is also applicable to some other types of potentials for N-identical interacting particles. 相似文献
914.
Thin films of Ti1−xCoxO2 (x=0 and 0.03) have been prepared on sapphire substrates by spin-on technique starting from metalorganic precursors. When heat treated in air at 550 and 700 °C, respectively, these films present pure anatase and rutile structures as shown both by X-ray diffraction and Raman spectroscopy. Optical absorption indicate a high degree of transparency in the visible region. Such films show a very small magnetic moment at 300 K. However, when the anatase and the rutile films are annealed in a vacuum of 1×10−5 Torr at 500 and 600 °C, respectively, the magnetic moment, at 300 K, is strongly enhanced reaching 0.36μB/Co for the anatase sample and 0.68μB/Co for the rutile one. The ferromagnetic Curie temperature of these samples is above 350 K. 相似文献
915.
The results of experimental investigations on thermal nonequilibrium ionization in CO2: N2: He mixtures are presented. Measurements of electron density, ne, in vibrationally excited nitrogen were made in a supersonic flow with different CO2 contents as well as in a CO2: N2: He = 1 : 5 : 4 mixture laser gas. The mixtures were heated in a shock tube and expanded through a supersonic nozzle. Furthermore, supersonic mixing of N2 and CO2 + He was used in some experiments. The measured values of ne in the plenum chamber and in the supersonic nozzle are reported, and the processes responsible for nonequilibrium ionization in a laser-active medium are discussed. 相似文献
916.
917.
A.J.?Lpez-Moreno 《Acta Mathematica Hungarica》2005,106(4):343-354
Summary We obtain preservation inequalities for Lipschitz constants of higher order in simultaneous approximation processes by Bernstein type operators. From such inequalities we derive the preservation of the corresponding Lipschitz spaces. 相似文献
918.
The effect of the amount of desorbed water on the mechanical properties of composites based on low-density polyethylene and linen yarn production waste (LW) is analyzed by statistical methods. It is shown that the amount of absorbed water decreases during the desorption process at room temperature both for specimens modified and unmodified with diphenylmethane diisocyanate (DIC.) The most sensitive to the action of water is the elastic modulus, which decreases considerably under the effect of water and is fully restored in the desorption process. The tensile strain also increases with the amount of absorbed water. It is found that the elastic modulus of the unmodified composite correlates linearly with the amount of desorbed water. Between the amount of desorbed water and the tensile strain, as well the specific work of deformation, a negative linear correlation is revealed. After water desorption, all strength and deformation characteristics of both the modified and unmodified composites are fully recovered.__________Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 515–524, July–August, 2005. 相似文献
919.
V. V. Kozlov 《Functional Analysis and Its Applications》2005,39(4):271-283
We discuss the symplectic geometry of linear Hamiltonian systems with nondegenerate Hamiltonians. These systems can be reduced to linear second-order differential equations characteristic of linear oscillation theory. This reduction is related to the problem on the signatures of restrictions of quadratic forms to Lagrangian planes. We study vortex symplectic planes invariant with respect to linear Hamiltonian systems. These planes are determined by the solutions of quadratic matrix equations of a special form. New conditions for gyroscopic stabilization are found. 相似文献
920.
M. Stangl V. Dittel J. Acker V. Hoffmann W. Gruner S. Strehle K. Wetzig 《Applied Surface Science》2005,252(1):158-161
At room temperature electroplated copper layers exhibit changes in resistivity, residual stress, and microstructure. This process, known as self-annealing, is intimately linked to the release of organic impurities, which stem from the incorporation of organic additives into the Cu layer in the course of the electroplating process. The behavior of these impurities during self-annealing, represented by the carbon content, could be detected by analytical radio frequency glow discharge optical emission spectrometry (GD-OES) and carrier gas hot extraction (CGHE). The precondition of a quantitative determination is a surface cleaning procedure to remove adsorbed organics from the copper surface. It was observed that at first almost all impurities have to leave the Cu metallization before an accelerated abnormal grain growth can start. The small amount of remaining organic species after self-annealing could be quantified by both examination techniques, GD-OES and CGHE. 相似文献