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61.
M. K. Pandey R. K. Dubey D. N. Tripathi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(2):275-279
The Classical Trajectory Monte Carlo (CTMC) Method has
been used to calculate the differential, partial and total single electron
capture cross sections for the collision of H+/D+ with Ca and Mg
atoms in the energy range of 1–100 keV. The differential cross sections
at angles near the diffraction limit (<0.1○) in both systems
show a forward peak followed by an asymptotic fall at higher angles. Total
and partial capture cross sections are found to be in good agreement with
the experimental observations. Oscillations in the partial capture cross sections have been explained due to the swapping
of the field electron.
Isotope effect in the electron transfer is reported to be negligible. 相似文献
62.
The concept of table algebra in the title is a real nonsingular generalized table algebra in the sense of [Z. Arad, E. Fisman, M. Muzychuk, Generalized table algebras, Israel J. Math. 114 (1999) 29–60]. In this paper we first give some definitions and facts about table algebras. It is well known that every association scheme gives a Hecke-algebra which is a table algebra too. This leads to the natural question which properties of association schemes stay valid for table algebras. For instance, we prove the Second Isomorphism Theorem and the Jordan–Holder's theorem for standard table algebras. 相似文献
63.
Summary We have studied the scattering of electrons by a structured target in the presence of a quantizing static magnetic field,
under the assumption that the presence of the field does not affect the behaviour of the massive target nuclei, but it influences
only the motion of the incident electrons. In this case, the electron motion in the plane perpendicular to the magnetic field
is confined within a typical distance given by the cyclotron radius ρ0=(cℏ/|e|B)1/2, that for particular values of the intensity of the magnetic field can be comparable with the distance between two scattering
centres. The known field-free interference conditions are modified, depending both on the energy of the incident particle
and on the intensity and the direction of the magnetic field. The general case of a three-dimensional scattering array has
been derived in detail. Numerical results are given for the case of two scattering centres in perpendicular geometry.
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction. 相似文献
64.
Erik Aurell 《Journal of statistical physics》1987,47(3-4):439-458
The two standard literature definitions of the function associated with the Feigenbaum attractor are not equivalent. The method due to Vulet al. and Feigenbaum is used to calculate the Haussdorff dimension of the Feigenbaum attractor, using as input the trajectory scaling functions. The two calculations yield the same Hausdorff dimensionD=0.5380451435 to within the accuracy of the computation. 相似文献
65.
N. R. Sadykov 《Theoretical and Mathematical Physics》2009,158(1):105-111
We show that the optical Magnus effect for dissipative solitons is determined not only by the helicity but also by the topological
index, i.e., by the magnetic quantum number or by the projection of the soliton orbital moment on its trajectory. In the case
of inhomogeneous media, we find a relation between the optical Magnus effect and the nonholonomy of the field of unit vectors
tangent to the trajectory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 158, No. 1, pp. 126–134, January, 2009. 相似文献
66.
67.
Quantum mechanical ab initio simulation of the electron screening effect in metal deuteride crystals
A. Huke K. Czerski S. M. Chun A. Biller P. Heide 《The European Physical Journal A - Hadrons and Nuclei》2008,35(2):243-252
In antecedent experiments the electron screening energies of the d+d reactions in metallic environments have been determined
to be enhanced by an order of magnitude in comparison to the case of gaseous deuterium targets. The analytical models describing
averaged material properties have not been able to explain the experimental results so far. Therefore, a first effort has
been undertaken to simulate the dynamics of reacting deuterons in a metallic lattice by means of an ab initio Hartree-Fock calculation of the total electrostatic force between the lattice and the successively approaching deuterons
via path integration. The calculations have been performed for Li and Ta, clearly showing a migration of electrons from host
metallic to the deuterium atoms. However, in order to avoid more of the necessary simplifications in the model the utilization
of a massive parallel supercomputer would be required. 相似文献
68.
H+SO2→OH+SO反应在燃烧、大气和星际化学中都扮演着重要角色. 它还是具有深势阱中间体形成的典型反应,是检验速率理论和提供有趣反应动力学现象的理想候选反应. 基于之前构建的全维高精度势能面,本文对该反应进行了准经典动力学研究. 在1400 K≤T≤2200 K的温度范围内,计算值重现了实验速率常数. 当反应物SO2处于振-转基态,在31.0∽40.0 kcal/mol的碰撞能范围内,计算得到的积分反应截面随碰撞能增加;在40∽55 kcal/mol的碰撞能范围内,积分反应截面几乎不受碰撞能影响. 产物角度分布呈现对称的前后向双峰结构. 本文还分析了产物OH和SO的振动态分布. 相似文献
69.
We address the problem of inverse dynamics for flexible multibodies, which arises, in trajectory tracking control of flexible multibodies such as space manipulators and articulated flexible structures. Previous research has resolved this trajectory tracking problem by computing the system inputs for feedforward control of actuators at the joints. Recently, the use of distributed actuators like electro-strictive actuators in flexible structures has introduced a new dimension to this trajectory tracking problem. In this paper we optimally utilize such actuators to aid joint actuators for tracking control, and introduce a new inverse dynamics scheme for simultaneously (1) tracking a prescribed trajectory and (2) minimizing ensuing elastic deflections. We apply this scheme for trajectory tracking of a two-link two-joint planar manipulator with joint motors and distributed electro-strictive actuators. Experimental results are presented to contrast our new scheme with other existing methods. 相似文献
70.
Residual stress field and reduction of stress intensity factors in cold-worked holes 总被引:1,自引:0,他引:1
S.T. Pinho H.B. Martins P.P. Camanho M.H. Santare P.M.S.T. de Castro 《Theoretical and Applied Fracture Mechanics》2005,44(2):168-177
Closed-form and semi-analytical solutions are obtained for the residual stress distributions in a plate caused by pressure acting on a central circular hole, representing the cold-work process. The material is elastic–perfectly plastic. Both Tresca and von Mises yield criteria are used and the corresponding residual stress distributions are compared. The relation between the dimension of the plastic zone and the value of internal pressure is presented. The relation between the magnitude of the residual stresses and the remote uniform tensile stress required to open symmetrical radial cracks is also presented. The reduction of the stress intensity factors of cracked open and riveted holes as a function of the internal pressure applied (or mandrel radial displacement) is investigated using numerical models for both an elastic–perfectly plastic material and for an Al 2024-T3 Alclad aluminum alloy. 相似文献