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971.
V. P. Makarov 《Theoretical and Mathematical Physics》2006,146(3):373-375
We show that the criticism of the well-known result for the spin—spin part of the Breit potential (see the paper by Kuz’menkov,
Maksimov, and Fedoseev, 2001) is erroneous. We prove that the formula for the Breit potential presented in the book by Berestetskii,
Lifshitz, and Pitaevskii is correct.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 146, No. 3, pp. 443–446, March, 2006. 相似文献
972.
C.H. Yang W. Xu Z. Zeng C.S. Tang C. Zhang 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):363
We present a theoretical study on how many-body effects can affect the spin-splitting of a two-dimensional electron gas in the presence of the Rashba spin–orbit interaction. The standard Hartree–Fock approximation and Green's function approach are employed to calculate the energy spectrum and density of states of a spin-split two-dimensional electron gas (2DEG). We find that the presence of the exchange interaction can enhance significantly the spin-splitting of a 2DEG on top of the Rashba effect. The physical reasons behind this important phenomenon are discussed. 相似文献
973.
Low-energy (0.4-1.2 eV) electron backscattering is applied for the investigation of kinetics of residual gas adsorption effect on the concentration and energy positions of surface electron states of Ge(1 1 1) surface. Chemosorption of residual gas molecules on Ge(1 1 1) at P ∼ 10−7 Pa and room temperature is shown to be most active during the first 48 h. Low concentration of dangling valence bonds on the reconstructed Ge(1 1 1) (2 × 8) surface is shown to determine its low activity to chemosorption. 相似文献
974.
The jump relations of the quadruple layer potential on a regular surface in three dimensions are derived. The jumps are shown to be proportional to the product of the density of the potential and the mean curvature of the underlying surface. 相似文献
975.
A skin–air model is developed to model the water barrier function of skin. The skin model is a porous solid saturated with a monovalent salt solution. The air model is a vapor diffusion model in non-moving air. In vivo measurements of water loss from human skin under varying ambient conditions are used to validate the model. 相似文献
976.
导体旋转椭球电学量的一种计算方法 总被引:8,自引:4,他引:4
用一种新方法,计算了孤立导体旋转椭球的面电荷密度、电容、电势和电场强度,并得出相应的解析表达式。 相似文献
977.
978.
S. Cafieri M. D’Apuzzo M. Marino A. Mucherino G. Toraldo 《Journal of Optimization Theory and Applications》2006,129(1):55-75
In this paper, we present an interior-point algorithm for large and sparse convex quadratic programming problems with bound
constraints. The algorithm is based on the potential reduction method and the use of iterative techniques to solve the linear
system arising at each iteration. The global convergence properties of the potential reduction method are reassessed in order
to take into account the inexact solution of the inner system. We describe the iterative solver, based on the conjugate gradient
method with a limited-memory incomplete Cholesky factorization as preconditioner. Furthermore, we discuss some adaptive strategies
for the fill-in and accuracy requirements that we use in solving the linear systems in order to avoid unnecessary inner iterations
when the iterates are far from the solution. Finally, we present the results of numerical experiments carried out to verify
the effectiveness of the proposed strategies. We consider randomly generated sparse problems without a special structure.
Also, we compare the proposed algorithm with the MOSEK solver.
Research partially supported by the MIUR FIRB Project RBNE01WBBB “Large-Scale Nonlinear Optimization.” 相似文献
979.
980.