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991.
We calculate aPT-odd one-loop meson radiative correction to the scattering amplitude of a nucleon on the external field of the nucleus. The nonrelativistic limit of this amplitude, Fourier transformed to the configuration space, can be interpreted as a single particlePT-odd potential for a valence nucleon. Bound state effects on this potential are evaluated and found to be negligible. 相似文献
992.
The Lie symmetries of nonlinear diffusion equations with convection term are completely described. The Lie ansatzes and exact solutions of a certain nonlinear generalization of the Murray equation are constructed. An example of the family of non-Lie solutions of the Murray equation is given. 相似文献
993.
994.
C. D. Schaper Y. M. Cho T. Kailath 《Applied Physics A: Materials Science & Processing》1992,54(4):317-326
A low-order model of rapid thermal processing (RTP) of semiconductor wafers is derived. The first-principles nonlinear model describes the static and dynamic thermal behavior of a wafer with approximate spatial temperature uniformity undergoing rapid heating and cooling in a multilamp RTP chamber. The model is verified experimentally for a range of operating temperatures from 400° C to 900° C and pressures of 1 Torr and 1 atmosphere in an inert N2 environment. Theoretical predictions suggest model validity over a still wider range of operating conditions. One advantage of the low-order model over previous high-order and statistical models is that the proposed model contains a small number of fundamental parameters and functions that, if necessary, are easily identifiable. Furthermore, because of reduced computational complexity, the low-order model can be used in real-time predictive applications including signal processing and process control design. In studying and verifying the model, the dynamic behavior of a semiconductor wafer undergoing rapid temperature changes is characterized. Close comparison between theory and experiment in terms of the wafer eigenvalue and dc gain is demonstrated; the strong nonlinear effects of temperature are shown. Convective heat transfer losses are also examined and are shown to increase with radial position on the wafer. 相似文献
995.
A. B. Drovosekov N. M. Kreines D. I. Kholin V. F. Meshcheryakov M. A. Milyaev L. N. Romashev V. V. Ustinov 《JETP Letters》1998,67(9):727-732
The excitation spectrum in an [Fe/Cr]n multilayer structure with non-collinear magnetic ordering was studied by the ferromagnetic resonance (FMR) method in the
frequency interval 9.5–37 GHz at room temperature. Besides an acoustic branch, several additional modes were observed under
parallel excitation of resonance. The FMR spectrum was calculated analytically in a biquadratic exchange model, neglecting
in-plane anisotropy, for an infinite number of layers in the structure and numerically for a finite number of layers contained
in real samples. It was shown that the observed modes correspond to excitation of standing spin waves with wave vectors perpendicular
to the film plane.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 9, 690–695 (10 May 1998) 相似文献
996.
D. A. Ténné V. A. Gaisler N. T. Moshegov A. I. Toropov A. P. Shebanin 《JETP Letters》1998,68(1):53-58
Experiments on Raman scattering in the “forward” geometry, permitting observation of anisotropy of the optical phonons, are
performed on specially prepared short-period GaAs/AlAs superlattice structures with the substrates removed and the surfaces
covered with an antireflective layer. The experimental data agree well with the computational results obtained for the angular
dispersion of optical phonons in superlattices on the basis of a modified continuum model.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 1, 50–55 (10 July 1998) 相似文献
997.
A new scheme is presented for the physical processes leading to the nuclear fusion reaction d(3He, 4He)p catalyzed by a negatively charged muon μ−. It is shown that the observable rate and yield of the nuclear reaction depend on a chain of ion-molecular reactions involving
the participation of the dμ 3He molecule. New calculations of the nuclear fusion rates in the dμ3He molecule are presented.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 2, 89–94 (25 January 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
998.
We use integrals of Cauchy type and the complex potentials of S. G. Lekhnitskii to solve the problem of the stress-strain
state of a piecewise-homogeneous anisotropic rock during the working of a horizontal seam of mineral. We study the stress
distribution in the deloaded zones. Three figures, 1 table. Bibliography: 4 titles.
Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 27, 1997, pp. 81–86. 相似文献
999.
The Zubarev nonequilibrium statistical operator is used to describe the generalized hydrodynamic state of a magnetic fluid
in an external magnetic field. The magnetic fluid is modeled with “liquid-state” and “magnetic” subsystems described using
the classical and quantum statistics methods respectively. Equations of the generalized statistical hydrodynamics for a magnetic
fluid in a nonhomogeneous external magnetic field with the Heisenberg spin interaction are derived for “liquid-state” and
“magnetic” subsystems characterized by different nonequilibrium temperatures. These equations can be used to describe both
the weakly and strongly nonequilibrium states. Some limiting cases are analyzed in which the variables of one of the subsystems
can be formally neglected.
Translated from Teoreticheskaya i Matematicheskaya Fizika. Vol. 115, No. 1, pp. 132–153, April, 1998. 相似文献
1000.
The study of the distribution of thermal fields and the thermal stresses they generate, and the influence of these factors
on the strength of piecewise-homogeneous bodies was begun and developed in the work of Ya. S. Pidstrigach, Yu. M. Kolyano,
and their students [5, 12, 13]. In the present paper we use the theory of generalized functions to reduce the two-dimensional
quasistatic problem of thermal stresses for piecewisehomogeneous bodies to solving systems of integral equations. The kernels
of these equations are chosen as the corresponding Green's functions. We obtain a single system of integral equations for
the entire region under consideration. To solve the system we apply the method of boundary elements [2]. On the basis of the
results obtained we carry out a study of the thermostressed state of a half-plane with rectangular inclusions.
Translated fromMatematichni Metodi i Fiziko-mekhnichni Polya, Vol. 40, No. 1, 1997, pp. 53–58. 相似文献