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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The specific features of the transformation and shift of a Gaussian beam reflected from a resonant absorbing medium are analyzed numerically. The study is based on the expansion of the field of the incident Gaussian beam into plane-wave components by using the Fourier integral transform. The calculations are performed for a frequency range covering the resonance region. The conditions for the splitting of the profile of the reflected beam and for its negative shift are established. 相似文献
992.
Michael I. Mishchenko 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,101(3):411-415
The volume integral equation formalism is used to prove the scale invariance rule for an arbitrarily sized scatterer with an arbitrary shape, morphology, and orientation. The only assumptions are that the scatterer is made of optically isotropic linear materials and is embedded in a homogeneous, linear, isotropic, and nonabsorbing infinite medium. 相似文献
993.
Surface reconstructions of InGaAs alloys 总被引:1,自引:0,他引:1
The surface reconstructions of InxGa1−xAs alloys grown by molecular beam epitaxy on the (0 0 1) surfaces of GaAs and InAs have been studied by reflection high-energy electron diffraction and scanning tunnelling microscopy. A surface phase diagram is presented for the nominally strain-free alloy as a function of substrate temperature and alloy composition, and structural models for the commonly observed 3× reconstructions are discussed. Two new, electronically stable structural models are described that account for the transition of the InxGa1−xAs surface alloy from a c(4 × 4) to an asymmetric 3× reconstruction and that are fully consistent with all current experimental evidence. 相似文献
994.
995.
Binding energy spectra of the valence electrons of the open shell molecule NO have been obtained up to 55 eV at azimuthal angles of 0° and 7° using binary (e, 2e) spectroscopy at an impact energy of 1200 eV. The momentum distribution has been obtained for the least tightly bound (unpaired) electron, removal of which leads to formation of the X 1Σ+ ground state of NO+. Momentum distributions have also been measured at 21.0 and 40.5 eV. The measured momentum distributions are compared with several literature wavefunctions of varying complexity. They are found to be in excellent agreement with those calculated using the natural spin orbital wavefunctions of Kouba and Ohrn. 相似文献
996.
I. V. Nezhinskaya 《Journal of Mathematical Sciences》2006,132(4):428-440
We consider the Neumann boundary value problem for the class of (p,q)-nonlinear elliptic equations. The numbers p and q, 2
⩽ p < q, characterize the power growth with respect to the gradient of eigenvalues of the leading matrix of the equation.
An a priori estimate for the maximum of the modulus of the gradient of the solution is obtained in a neighborhood of the boundary
of the domain for some interval of p and q. Bibliography: 5 titles.
__________
Translated from Problemy Matematicheskogo Analiza, No. 31, 2005, pp. 47–57. 相似文献
997.
I. A. Polonsky A. E. Romanov V. G. Gryaznov A. M. Kaprelov 《Czechoslovak Journal of Physics》1991,41(12):1249-1255
The elastic fields generated by a straight-line screw dislocation axially arranged in a spherical particle have been calculated and analyzed. Some features of the distribution of elastic fields in this case and in the case of a screw dislocation lying along the axis of a cylindrical whisker are similar. The elastic energies per unit dislocation length differ slightly in the two cases. This corroborates the validity of application of some of the results obtained for screw dislocations in elastic cylinders to the study of properties of screw dislocations in equiaxed particles.Authors are very indebted to dr. A. B. Lebedev for his kind support. 相似文献
998.
999.
V. M. Kuz’kin O. Yu. Lavrova S. A. Pereselkov V. G. Petnikov K. D. Sabinin 《Acoustical Physics》2006,52(1):65-76
The space-time spectral characteristics of the field of background internal waves (IW) are obtained for two oceanic shelf
regions (the Atlantic shelf of the United States and the Kamchatka shelf) and analyzed. Within the framework of a numerical
experiment, it is shown that the observed anisotropy of the IW field may considerably affect the low-frequency sound fluctuations
in the aforementioned regions and, in particular, may change the interference invariant of the sound field. 相似文献
1000.
A. I. Alekseev 《Few-Body Systems》2006,40(1-2):57-70
Based on a study of the analytic running coupling obtained from the standard perturbation-theory results up to four-loop order,
the QCD “synthetic” running coupling αsyn is built. In so doing the perturbative time-like discontinuity is preserved and nonperturbative contributions not only remove
the nonphysical singularities of the perturbation theory in the infrared region but also decrease rapidly in the ultraviolet
region. In the framework of the approach, on the one hand, the running coupling is enhanced at zero and, on the other hand,
the dynamical gluon mass m
g
arises. Fixing the parameters which characterize the infrared enhancement corresponding to the string tension σ and normalization,
say, at M
τ completely define the synthetic running coupling. In this case the dynamical gluon mass appears to be fixed and the higher-loop
stabilization property of m
g
is observed. For σ = (0.42 GeV)2 and αsyn(M
τ
2) = 0.33 ± 0.01 it is obtained that m
g
= 530 ± 80 MeV.
Deceased 相似文献