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101.
Translated from Aktual'nye Voprosy Prikladnoi Matematiki, pp. 222–228, 1989. 相似文献
102.
A. S. Kosmodamianskii V. I. Storozhev V. A. Shpak 《Journal of Mathematical Sciences》1991,57(1):2918-2922
A solution is constructed for an orthotropic layer with free plane faces, that corresponds to the plane elastic waves symmetric over the thickness. The dynamical reconstruction of the normal wave spectrum during rotation of the wave vector from one to another elastically equivalent direction is investigated on the basis of a numerical analysis of the dispersion equation.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 19, pp. 116–121, 1988. 相似文献
103.
Defect formation and annealing processes in fullerene C60 at T = (4000–6000) K are studied using molecular dynamics with a tight-binding potential. The cluster lifetime until fragmentation, which proceeds, as a rule, through the loss of a C2 dimer, has been found as a function of temperature. The activation energy and the frequency factor in the Arrhenius equation for the fragmentation rate have been found to be E a = (9.2 ± 0.4) eV and A = (8 ± 1) × 1019s?1. It is shown that fragmentation can occur already after the C60 cluster loses its spherical shape. This fact must be taken into account in theoretical calculations of E a. 相似文献
104.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 6, pp. 965–969, June, 1991. 相似文献
105.
I.L. Lyubchanskii N.N. Dadoenkova M.I. Lyubchanskii E.A. Shapovalov A.E. Zabolotin K.Y. Guslienko T. Rasing 《Applied physics. B, Lasers and optics》2002,74(7-8):711-714
Nonlinear (at the second-harmonic frequency of the incident light) optical reflection by two-dimensional magnetic superstructures
is theoretically studied. A square lattice of magnetic dots and a hexagonal lattice of magnetic bubbles (cylindrical magnetic
domains) are considered. Because the periods of these structures are comparable with the wavelengths of the fundamental and
the second-harmonic radiation, it would be possible to observe diffraction at the second-harmonic frequency. A polarization
analysis of nonlinearly diffracted radiation is performed and the numbers of observable diffraction orders for the above structures
are estimated.
Received: 10 January 2002 / Published online: 11 June 2002 相似文献
106.
V. I. Psarev 《Russian Physics Journal》1991,34(12):1110-1113
A method is proposed for determining the similarities and differences between the experimental distribution of particles in a disperse system with respect to a significant feature-particle size (sample) and the corresponding distribution (likeness), selected from the diversity of theoretical distributions with positive and negative asymmetry. The aim of the comparison is to extract the necessary information about the nature of the internal processes in the disperse system evolving as a result of the Ostwald reaction coagulation of microparticles. The procedure of comparing the distributions is illustrated on the example of the histogram of disperse Al3Mg2 particles of an aluminum-magnesium alloy heated isothermally at 430°C.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 80–84, December, 1991. 相似文献
107.
108.
I. V. Yakushin 《Russian Physics Journal》1991,34(12):1090-1094
The contribution of the interacting vector and pseudovector torsion components to the interaction of polarized photons in an atomic sodium vapor is investigated. Estimates are obtained for the parameters of the gauge-theoretical model of gravitation.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 50–55, December, 1991. 相似文献
109.
D. D. Bainov S. I. Kostadinov P. P. Zabreiko 《International Journal of Theoretical Physics》1992,31(8):1521-1526
Necessary and sufficient conditions for the existence of an exponential dichotomy of impulsive differential equations in a Hilbert space are found. 相似文献
110.
I Cserpan M Kalman M L Tj?rnhammar A Simoncsits 《Acta chemica Scandinavica (Copenhagen, Denmark : 1989)》1991,45(3):265-272
A general method to convert single-stranded, chemically synthesized oligonucleotides into cloned duplexes is described. Oligonucleotides supplied with 3'-terminal extensions that are complementary to 3'-protruding ends obtained by certain restriction enzymes can be cloned either directly or with the help of an adapter molecule into double-stranded vectors. Two methods have also been developed for consecutive cloning applications. According to these methods, the synthetic oligonucleotides (and their enzymatically prepared complementary strands) are joined, one after the other, inside a cloning vector, each joining requiring one cloning step. Synthetic genes are thus built up from oligonucleotides corresponding to only one strand of the DNA. The sequential assembly of the cloned duplex takes place in the 5' to 3' direction. Each oligonucleotide is supplied with a four-nucleotide-long 3'-terminal extension, but this sequence is eliminated when the joining takes place, leaving no limiting sequence between the oligonucleotides. The two consecutive cloning methods, the adapter and the polycloning site methods, are illustrated by the assembly of short artificial genes. 相似文献