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101.
Palacián JF 《Chaos (Woodbury, N.Y.)》2005,15(3):33111
We propose a method to decompose a smooth vector field into conservative and dissipative components. The procedure is based on the identification of the kernel of a linear operator associated with a given Hamiltonian combined with the use of Lie transformations for vector fields. Moreover, under certain conditions the nonconservative part of the splitting can be dropped at a given order of the transformation, obtaining after truncation, a Hamilton vector field. The technique is illustrated through the application to the motion of a particle subject to the potential of a champagne bottle plus a small friction. 相似文献
102.
103.
Zúñiga-Pérez J Muñoz-Sanjosé V Palacios-Lidón E Colchero J 《Physical review letters》2005,95(22):226105
The surface electrical properties of ZnO thin films grown along the nonpolar [1120] direction have been investigated by Kelvin probe microscopy on a nanometer scale. Two different charge domains, with a 75 meV work function difference, coexist within the ZnO surface, which is covered by rhombohedral pyramids whose sidewalls are shown to be {1011}-type planes. The presence and relative orientation of the two kinds of charge domains are explained in terms of the atomic arrangement at the {1011} polar surfaces. 相似文献
104.
The short-time dynamic properties of colloidal particles in quasi-two-dimensional geometries are studied by digital video microscopy. We demonstrate experimentally that the effective-two-dimensional physical quantities such as the dynamic structure factor, the hydrodynamic function, and the hydrodynamic diffusion coefficients are related in exactly the same manner as their three-dimensional counterparts. 相似文献
105.
A new route for the degradation of the saturated side chain of dihydrozamoranic acid has been devised, giving an advanced intermediate, compound 14, useful for the synthesis of insect antifeedants such as warburganal and polygodial. 相似文献
106.
Complexes [Pd(3)(mu(3)-S)(mu(3)-X)(L)(3)] (L = orthometalated imine), obtained by an unusual reaction of mu(2)-OH dimeric complexes and CS(2), are an unprecedented type of asymmetrical bridges between metallatriangles, which force an all-cis arrangement of the three orthometalated ligands relative to the metallatriangle. 相似文献
107.
108.
For a synthetic hexasaccharide model it is shown that the conformational flexibility of the L-iduronate ring in glycosaminoglycans can be adequately described by using the PME methodology together with simulation protocols suitable for highly charged systems. 相似文献
109.
Ortiz-Marciales M González E De Jesús M Espinosa S Correa W Martínez J Figueroa R 《Organic letters》2003,5(19):3447-3449
[reaction: see text] Representative B-butyl- and B-methyl-1,3,2-oxazaborolidines derived from ephedrine and norephedrine were prepared in good yield and excellent purity by one-pot treatment of B-H oxazaborolidines with the corresponding organolithium reagent and subsequent hydrolysis of the cyclic borohydride intermediate with anhydrous ammonium chloride. 相似文献
110.