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991.
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993.
三层介质长圆柱界面上极化电荷和磁化电流的分立镜像 总被引:1,自引:0,他引:1
计算表明,三层介质无工圆柱界面上的极化电荷和磁化电流可用多个分立镜像代替,从而使电场和磁场的计算更简单和直观。 相似文献
994.
Wei‐Ping Su Mao‐Chun Hong Rong Cao Jia‐Bao Weng Zhong‐Yuan Zhou S. C. Chan Albert 《中国化学》2001,19(9):817-821
The supramolecular silver(I)‐thiolate complex [Ag(μ2‐SC4N2H4)2(SCN)]n has been prepared from the reaction of AgSCN and pyrimidine‐2‐thiol in DMF. X‐ray diffraction analysis shows that the supramolecular structure exhibits one‐dimensional chain through the secondary Ag‐S interactions and the chains are further linked by strong hydrogen bonds to form a three dimensional network. The luminescence effect from the silver‐centered state of S→Ag LMCT in solid state is different from that in solution due to the secondary Ag‐S interactions. 相似文献
995.
Ni(OAc)2 was found to be an efficient catalyst for the synthesis of β‐enamino ketones or esters from β‐dicarbonyl compounds and amines under solvent‐free conditions. The reusability of the catalyst was successfully examined without noticeable loss of its catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
996.
997.
Dong-Xing Cao·Wei Zhang·Ming-Hui Yao College of Mechanical Engineering Beijing University of Technology Beijing China 《Acta Mechanica Sinica》2010,26(6):967-976
This paper focuses on theoretical and experimental investigations of planar nonlinear vibrations and chaotic dynamics of an L-shape beam structure subjected to fundamental harmonic excitation,which is composed of two beams with right-angled L-shape.The ordinary differential governing equation of motion for the L-shape beam structure with two-degree-of-freedom is firstly derived by applying the substructure synthesis method and the Lagrangian equation.Then,the method of multiple scales is utilized to obtain a four-dimensional averaged equation of the L-shape beam structure.Numerical simulations,based on the mathematical model,are presented to analyze the nonlinear responses and chaotic dynamics of the L-shape beam structure.The bifurcation diagram,phase portrait,amplitude spectrum and Poincare map are plotted to illustrate the periodic and chaotic motions of the L-shape beam structure.The existence of the Shilnikov type multi-pulse chaotic motion is also observed from the numerical results.Furthermore, experimental investigations of the L-shape beam structure are performed,and there is a qualitative agreement between the numerical and experimental results.It is also shown that out-of-plane motion may appear intuitively. 相似文献
998.
The tree graph method of evaluating the local molecular moment is proposed. By applying this method and the molecular moment
formula of π-electron energy in the molecular orbital graph theory, a topological method of using the molecular moment to
judge the relatively reactive point of even AH is achieved. 相似文献
999.
Yaliang Shen Yueping Zhu Nanbin Cao 《Communications in Nonlinear Science & Numerical Simulation》2009,14(4):1176-1185
The overall aim of the present paper is to find and analyze the new non-travelling wave solutions of the nonlinear evolution and wave equations. With the aid of symbolic computation and based on the generalized extended tanh-function method, we propose the newly extended tanh-function expansion algorithm and get many new non-travelling wave solutions of the (2 + 1)-dimensional Broer–Kaup–Kupershmidt equations. The solutions which we obtain are more abundant than the solutions which the generalized extended tanh-function method gets. At the same time, the solutions contain arbitrary functions which may be helpful to explain some complex phenomena. We also give some figures to describe the property of these solutions. In additions, the method can also be successfully applied to other nonlinear evolution and wave equations. 相似文献
1000.