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241.
An efficient general algorithm for the computation of molecular momentum intracule densities from Hartree-Fock wavefunctions using Gaussian basis functions is described. The momentum intracules for a number of systems are examined, and comparison with their position space counterparts discussed. 相似文献
242.
Time-delayed nonlinear evolution equations and boundary value problems have a wide range of applications in science and engineering. In this paper, we implement the differential transform method to solve the nonlinear delay differential equation and boundary value problems. Also, we present some numerical examples including time-delayed nonlinear Burgers equation to illustrate the validity and the great potential of the differential transform method. Numerical experiments demonstrate the use and computational efficiency of the method. This method can easily be applied to many nonlinear problems and is capable of reducing the size of computational work. 相似文献
243.
In fluid-structure interaction systems, baffles as a dynamic damping device are being widely used to suppress the fluid sloshing motion. Meanwhile, natural and dynamic behaviors of such systems are significantly influenced by the baffle parameters, such as the baffle number, the installation location, the inner-hole diameter and the liquid fill height. This paper intends to numerically investigate the parametric eigen characteristics, by the coupled structural-acoustic finite element method (FEM), of baffled cylindrical liquid-storage tank. According to the symmetric two-field formulation, a test FEM program is developed, in which the reduced integration for avoiding the shear and membrane locking and the modified shear correction factor as well as degenerated 8- and 6-node shell elements and 3-D trilinear acoustic elements are used. Through the comparison with the available analytic solutions of no-baffled axisymmetric tank, the validity of the test program and theoretical work is verified. Next, with the verified test FEM program, various combinations of major baffle parameters are intensively examined, in order for the parametric baffle effects on the natural frequency of baffled tanks. 相似文献
244.
Kuo Hsiung LEE 《中国化学快报》2005,(10)
In our prior studies,3′,4′-di-O-(S)-camphanoyl-(+)-cis-khellactone(DCK,1,Figure1)and its derivatives including mono-and di-substituted DCK analogs were identified as a novel class of potent anti-HIV agents1-4.Because of its high potency and efficient syn-thesis,4-methyl-DCK25was chosen as a drug candidate for preclinical studies.How-ever,the low solubility and poor oral bioavailability of4-methyl-DCK limited its further development.Because high molecular hydrophobicity might be one re… 相似文献
245.
246.
THE -PROBLEM FOR HOLOMORPHIC (0,2)-FORMS ON PSEUDOCONVEX DOMAINS IN SEPARABLE HILBERT SPACES AND D.F.N. SPACES 下载免费PDF全文
This paper shows that the -problem for holomorphic (0, 2)-forms on Hilbert spaces is solv able on pseudoconvex open subsets. By using this result, the authors investigate the existence of the solution of the -equation for holomorphic (0, 2)-forms on pseudoconvex domains in D.F.N. spaces. 相似文献
247.
Y.Y. LEE 《Journal of sound and vibration》2003,259(3):625-636
In this paper, the insertion loss of a cavity-backed semi-cylindrical enclosure panel is studied theoretically and experimentally. The classical approach based on Narayanan [1] and Lee [2] is employed to the semi-cylindrical enclosure modelling. The theoretical model considers the three-dimensional acoustic modes of the semi-cylindrical cavity and the noise source vibration mode shape. The experimental result agrees reasonably with the theoretical prediction. It is found that the higher structural resonance in the semi-cylindrical can significantly deteriorate the insertion loss performance while only the (1,1) mode structural resonance in the rectangular models is the important one. The noise source panel vibrating in the (3,1) mode shape induces higher air pressure on the semi-cylindrical panel through the air cavity than the (1,1) mode shape. 相似文献
248.
249.
We develop a method for calculation of the total reaction cross sections induced by the halo nuclei and stable. nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energies. It is extended for nuclear reactions at low energies and intermediate energies by including both the quantum correction and Coulomb correction under the assumption of the effective nuclear density distribution. The calculated results of the total reaction cross section induced by stable nuclei agree well with 30 experimental data within 10 percent accuracy. The comparison between the numerical results and 20 experimental data for the total nuclear reaction cross section induced by the neutron halo nuclei and the proton halo nuclei indicates a satisfactory agreement after considering the halo structure of these nuclei, which implies quite different mean fields for the nuclear reactions induced by halo nuclei and stable nuclei. The halo nucleon distributions and the root-mean-square radii of these nuclei can be extracted from the above comparison based on the improved Glauber model, which indicates clearly the halo structures of these nuclei. Especially,it is clear to see that the medium correction of the nucleon-nucleon collision has little effect on the total reaction cross sections induced by the halo nuclei due to the very weak binding and the very extended density distribution. 相似文献
250.
采用柠檬酸合成高分散铜催化剂用于选择氢解反应 总被引:3,自引:0,他引:3
A highly dispersed Cu catalyst supported on silica was prepared by an incipient wetness impregnation method with citric acid.The synthesis was studied by nitrogen physisorption,X-ray diffraction,and temperature-programmed reduction by comparing with a reference prepared without citric acid.The catalyst precursor obtained after impregnation was X-ray amorphous.The precursor was readily transformed to crystalline CuO upon calcination.The CuO particles were of uniform size in a highly dispersed state and can be reduced to Cu at a lower temperature.The activity of the Cu catalyst obtained was an order of magnitude higher than that of the reference for the hydrogenolysis of methyl laurate to dodecanol. 相似文献