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991.
对无限大导体表面,楔形导体表面,半圆柱形凸起表面电荷面密度进行了具体的计算,结果表明在静电平衡的条件下导体表面虽曲率相同,但表面电荷面密度却可以不同. 相似文献
992.
Sergei V. Shirin Oleg L. Polyansky Nikolai F. Zobov Roman I. Ovsyannikov Jonathan Tennyson 《Journal of Molecular Spectroscopy》2006,236(2):216-223
Adiabatic potential energy surfaces (PESs) for three major isotopologues of water, H216O, H217O, and H218O, are constructed by fitting to observed vibration-rotation energy levels of the system using the nuclear motion program DVR3D employing an exact kinetic energy operator. Extensive tests show that the mass-dependent ab initio surfaces due to Polyansky et al. [O.L. Polyansky, A.G. Császár, S.V. Shirin, N.F. Zobov, P. Barletta, J. Tennyson, D.W. Schwenke, P.J. Knowles, Science 299 (2003) 539-542.] provide an excellent starting point for the fits. The refinements are performed using a mass-independent morphing function, which smoothly distorts the original adiabatic ab initio PESs. The best overall fit is based on 1788 experimental energy levels with the rotational quantum number J = 0, 2, and 5. It reproduces these levels with a standard deviation of 0.079 cm−1 and gives, when explicit allowance is made for nonadiabatic rotational effects, excellent predictions for levels up to J = 40. Theoretical linelists for all three isotopologues of water involved in the PES construction were calculated up to 26 000 cm−1 with energy levels up to J = 10. These linelists should make an excellent starting point for spectroscopic modelling and analysis. 相似文献
993.
This is the first of a couple of papers in which the peculiar capabilities of the Hamiltonian approach to general relativity
are exploited to get both new results concerning specific technical issues, and new insights about old foundational problems of the theory. The first paper includes: (1) a critical analysis of the various concepts of symmetry
related to the Einstein-Hilbert Lagrangian viewpoint on the one hand, and to the Hamiltonian viewpoint, on the other. This
analysis leads, in particular, to a re-interpretation of active diffeomorphisms as passive and metric-dependent dynamical symmetries of Einstein's equations, a re-interpretation which enables to disclose the (not widely known)) connection
of a subgroup of them to Hamiltonian gauge transformations on-shell; (2) a re-visitation of the canonical reduction of the ADM formulation of general relativity, with particular emphasis on
the geometro-dynamical effects of the gauge-fixing procedure, which amounts to the definition of a global non-inertial, space-time laboratory. This analysis discloses the peculiar dynamical nature that the traditional definition of distant simultaneity and clock-synchronization assume in general relativity, as well as
the gauge relatedness of the “conventions” which generalize the classical Einstein's convention. (3) a clarification of the physical role of Dirac
and gauge variables, as their being related to tidal-like and generalized inertial effects, respectively. This clarification is mainly due to the fact that, unlike the standard formulations of the equivalence principle,
the Hamiltonian formalism allows to define a generalized notion of “force” in general relativity in a natural way. 相似文献
994.
995.
William J. Rolli 《Journal of Mathematical Analysis and Applications》2006,321(1):388-395
In this paper, we use the characterization of frames, introduced in [W. Rolli, A characterization of frames for finite dimensional Hilbert spaces, preprint], to construct frames for finite dimensional Hilbert spaces. Furthermore this approach allows for the construction of frames with prescribed properties. 相似文献
996.
S Kailas R Vandenbosch A Charlop A Garcia S Gil S J Luke B McLain D Prindle 《Pramana》1990,35(5):439-447
The fusion cross section for the system6Li+28Si has been measured atE∼36 MeV. Combining this with the data available at lower energies, the nucleus-nucleus real potentials have been determined
for a range of interaction distances. 相似文献
997.
本文讨论了一类带调和势|x|^2的非线性Schroedinger方程解的长时间行为,证明了整体吸引子的存在性. 相似文献
998.
Haruko Ikeuchi Kaoru Naganuma Marie Ichikawa Hiromichi Ozawa Tomoya Ino Makoto Sato Hiroko Yonezawa Sonomi Mukaida Akihiro Yamamoto Takeshi Hashimoto 《Journal of solution chemistry》2007,36(10):1243-1259
The diffusion coefficients of several tris(β-diketonato) ruthenium complexes in acetonitrile solutions containing a supporting electrolyte were determined by chronoamperometry.
The diffusion coefficients of the charged complexes, which were produced by electrochemical oxidation or reduction, were also
determined by double potential step chronoamperometry. Two kinds of radii of the complexes were evaluated. One was the Van
der Waals radius and the other was the geometric distance from the center of the complex to the outer surface of the farthest
atom. The latter quantity was determined from X-ray diffractometric data. The diffusion coefficients of the neutral complexes
were discussed on the basis of the Stokes-Einstein equation. Those of charged complexes could not be explained by the theoretical
equation presented by Hubbard and Onsager. 相似文献
999.
1000.
T. Q. Dang 《国际流体数值方法杂志》1993,16(9):777-791
This paper summarizes a combined analytical-computational technique which models vortex sheets in transonic potential-flow methods. In this approach, the inviscid nature of discontinuities across vortex sheets is preserved by employing the step function to remove singularities at these surfaces. The location and strength of the vortex sheets are determined by satisfying the flow-tangency boundary condition and the vorticity transport equation. The theory is formulated for the general three-dimensional case, but its application is confined to the problem of computing slipstreams behind propellers with free-vortex blading in axisymmetric flows. 相似文献