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961.
A base of the universal multiplicative envelope of the free Malcev superalgebra ℳ on one odd generator is constructed. Some
corollaries for skew-symmetric functions and central elements in free Malcev and free alternative algebras are obtained. Moreover,
a base of the Poisson-Malcev superalgebra of ℳ is constructed. As a corollary, a set of elements that spans the free alternative
superalgebra on one odd generator is obtained.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 4, pp. 97–106, 2004. 相似文献
962.
We investigate the Landau damping of Bogoliubov excitations in a dilute Bose gas moving in an optical lattice at a finite temperature. Using a 1D tight-binding model, we explicitly obtain the Landau damping rate, the sign of which determines the stability of the condensate. We find that the sign changes at a certain velocity, which is exactly the same as the critical velocity determined by the Landau criterion of superfluidity. This coincidence reveals the microscopic mechanism of the Landau instability. 相似文献
963.
964.
It is demonstrated theoretically that the initial (both elastic and viscous) magnetic susceptibility components for nanocrystalline
magnets caused by the processes of rotations (in the region of linear response) have resonant rather than relaxation character
typical already for the susceptibility component caused by displacements of domain boundaries.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 88–92, June, 2007. 相似文献
965.
966.
A. V. Govorkov A. Ya. Polyakov T. G. Yugova N. B. Smirnov E. A. Petrova M. V. Mezhennyi A. V. Markov I. -H. Lee S. J. Pearton 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(4):380-385
The relation between the density of etch pits revealed in GaN by etching in a KOH/NaOH eutectic and the density of dislocations determined by transmission electron microscopy (TEM) is studied along with the relation between the density of dislocations and the density of dark spot defects observed in GaN by microcathodoluminescence (MCL) and electron-beam-induced current (EBIC). It is demonstrated that selective etching is a reliable rapid method for the determination of the type and density of dislocations in GaN in the range 106–108 cm?2, while MCL and EBIC can be used for the rapid nondestructive determination of the density of dislocations in the range 106–108 cm?2. It is also found that some deep electron and hole traps are related to dislocations. 相似文献
967.
N. B. Valetova L. L. Semenycheva I. S. Il’ichev A. N. Artemov D. F. Grishin 《Russian Journal of Applied Chemistry》2007,80(5):818-821
Features of radical polymerization of styrene in the presence of (diphenylbutadiene)tricarbonylchromium were studied. 相似文献
968.
V. M. Arzhavitin 《Technical Physics》2003,48(6):797-799
The stressed state of in metallic composite systems is analyzed. It is analytically shown that the temperature dependences of the internal friction in the composites may have extrema that are caused by internal stresses. The analytical results are supported by the experimental temperature dependences of the internal friction in (Cu-13% Sn)-30% Nb and Cu-1.3% Cr composites. 相似文献
969.
Toluene adsorption reactions on the (1 1 0) surface of VSbO4 have been analyzed following the changes in the electronic structure of the hydrocarbon molecule and metal cation sites of the oxide using the Just Another Extended Hückel Molecular Orbital Program (JAEHMOP) code. The bonding character of these interactions has also been studied in the same theoretical framework. The calculations indicate that the exothermic hydrocarbon parallel interaction on Sb-V sites results in the weakening of one of the C-H bonds of the methyl fragment. This leads to a H-abstraction that involves the participation of a Sb-cation. Both methyl and phenyl fragments decrease their electronic population and so does the V-cation site. Most of these electrons are transferred to other V atoms in the bulk solid. As a result the LUMO of the toluene-oxide system fully populates. The analysis reveals that methyl-Sb bonding interactions mainly involve C2px and H1s orbitals with Sb5s orbital, while non-bonding phenyl-V interactions involve C2px orbitals with V3dx2−y2 orbital. This last interaction facilitates the desorption of the benzyl species after H-abstraction. 相似文献
970.