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971.
We perform the Painlevé test for a coupled Higgs system to determine its Painlevé integrability. Moreover, a class of exact complexiton-like solutions, including breather solutions and dark and bright solitary solutions, is explicitly constructed for the coupled Higgs model by using a generalized Hirota’s bilinear form. 相似文献
972.
Yan-Qiu Deng Zhen-Wei Zhang Ya-Hui Feng Albert S.C. Chan Gui Lu 《Tetrahedron: Asymmetry》2012,23(24):1647-1652
An effective asymmetric synthesis of optically active 1,3-dinitro compounds via the direct Michael addition of nitroalkanes onto nitroalkenes has been described. In the presence of readily modified cinchona alkaloid derivatives, nitroethane reacted well with a variety of aromatic and heterocyclic aromatic nitroalkenes to afford products with good diastereoselectivities (dr up to 72/28) and enantioselectivities (ee up to 94%). The catalyst loading can be decreased to 2 mol % without compromising the asymmetric induction or the reaction rate. 相似文献
973.
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976.
In this work it was presented an application of task specific onium salt as soluble support for the synthesis of 3-amino-5-aryl-2,5- dihydropyridazines.This soluble support is of wide applicability and combines advantages of solid phase synthesis without its limitations with those of solution phase chemistry.After a simple washing step,products were cleaved from the supports and obtained in good yields. 相似文献
977.
Chen Guang Xu Bai Qiang Xu Gui Dong Xu 《Applied Physics A: Materials Science & Processing》2011,105(2):379-386
A model based on the theory of fluid–structure interaction is developed to simulate the laser thermoelastic generation and propagation of Leaky Lamb waves at the water–aluminum interface. Each component of displacement, stress, and temperature are derived in transform domain by the photothermoelastic transfer matrix method. The time domain solutions are obtained by numerically inverting the transforms while the dispersion curves and attenuation curves for the leaky waves are also calculated. Then the propagation characteristics of different modes are analyzed. The model establishes a quantitative relation between the laser parameters, the material parameters, the corresponding waveforms, and the dispersion curves, which provides a useful tool for the Leaky Lamb waves applied to nondestructive evaluation. 相似文献
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979.
Ming Jie ZHANG* Ling HUANG Xiu Fang SHI De Qing GAO Song Lin LI Gui Mei CAI Yan Yi HUANG Guang Qing YAO Jing LI Department of Chemistry Tianjin University Tianjin State Key Laboratory of Rare Earth Materials Chemistry App 《中国化学快报》2001,(7)
Imidazole groups play an important role in the coordination chemistry of the metal ions in many biological systems1. Earlier work has established its suitability for formations of binuclear copper1, iron2 and manganese3 complexes. Reaction of EDTB with Cu(H2O)6(BF4)2 in absolute ethanol has given a six-coordinate complex of [Cu(EDTB)](BF4)(BF3?O(C2H5)2)H2O4. Rare earth ions have similar physical and chemical properties with Ca2+ and Mg2+ which are important in biological systems. Wan… 相似文献
980.
Changfeng Gui 《Frontiers of Mathematics in China》2008,3(2):195-204
Using the Hamiltonian identities and the corresponding Hamiltonian constants for entire solutions of elliptic partial differential
equations, we investigate several new entire solutions whose existence were shown recently, and show interesting properties
of the solutions such as formulas for contact angles at infinity of concentration curves.
相似文献