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901.
本文引入单参数λ,利用β函数,建立Hardy-Hilbert不等式与Mulholland不等式的一个具有最佳常数因子的联系式.作为应用,给出它的等价形式及一些特殊结果. 相似文献
902.
An analytic expression of the potential energy surface (PES) of the ground state of the Ne-HF complex is obtained by utilizing
nonlinear least square method to fit the intermolecular interaction energies [Zhang Y. Guizhou Science, 2003, 21(3): 9–13 (in Chinese)], which have been computed using the augmented correlation-consistent polarized quadruple
zeta basis set aug-cc-pVQZ at the theoretical level of CCSD (T). On the basis of the PES, the partial cross sections (PCSs)
at the incident energies of 60, 75, 100 and 150 meV for collisions between Ne atoms and HF molecules are calculated using
the quantum close coupling approach. The effects of the long-range attractive and the short-range anisotropic interactions
on the inelastic PCSs are discussed in detail. The results show: (1) The long-range attractive well of the EPS makes the significant
contribution to the lower excitation PCSs, especially the tail maximum for j = 0→j′ = 1 transitions, whereas no contribution is to the j′⩾3 inelastic transitions. (2) The short-range (the repulsive and attractive) interaction makes the significant contribution
to the lower excitation PCSs, especially the main peak for j = 0→j′ = 1, 2. As for the transitions of j′⩾3, the short-range interaction plays a key role in the inelastic excitation. (3) Although the positions of the maximums
and minimums of the inelastic PCSs are different at the collision energies, they correspond to almost the same impact parameter.
Supported by the National Natural Science Foundation of China (Grant Nos. 10676025 and 10574096) 相似文献
903.
In this paper, the existence of solutions for a system of nonlinear equations is considered. n2 nonzero real solutions are obtained by using the critical point theory. Additionally, the Dirichlet boundary value problems of even order difference equations and partial difference equations are investigated. 相似文献
904.
Naturally existing tritium in groundwater was applied as a tracer to evaluate the natural recharge of the Chingshui geothermal reservoir. The residence time (or, age) of Chingshui geothermal water was first determined with tritium data at 15.2 and 11.3 year using the plug flow and dispersive model, respectively. The annual natural recharge was then estimated by combining the use of the residence time and the fluid-in-place of the Chingshui geothermal reservoir. The natural recharge for Chingshui geothermal reservoir was estimated at 5.0 × 105 and 6.7 × 105 m3 year?1 using the plug flow and dispersive model, respectively. Chingshui geothermal water is largely from a fractured zone in the Jentse Member of the Miocene Lushan Formation. The dispersive model more adequately represents the fracture flow system than the simple plug flow model. 相似文献
905.
Ming Cheng 《Mathematical Methods in the Applied Sciences》2014,37(5):645-656
In the present paper, we consider the dissipative coupled fractional Schrödinger equations. The global well‐posedness by the contraction mapping principle is obtained. We study the long time behavior of solutions for the Cauchy problem. We prove the existence of global attractor. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
906.
907.
908.
Feng-Hsi Huang Ching-Chung Chen Dar-Jong Lin Trong-Ming Don Liao-Ping Cheng 《Journal of nanoparticle research》2010,12(8):2941-2950
A series of photochromic phosphotungstic acid (PWA)/SiO2 composites were synthesized using the sol-gel method. Depending on the feeding schedule of PWA during synthesis, the size of the formed PWA/SiO2 particles varied considerably from as small as 1.2 nm to ca. 10 nm. With decreasing silica particle size, the total contact area/interaction between SiO2 and PWA increases, as revealed by FT-IR and solid-state 29Si-NMR analyses. Particularly, when the size of PWA/SiO2 is ~1 nm, crystallization of PWA is inhibited, and PWA presents as amorphous molecular entities distributing uniformly in the SiO2 host, which is in evidence in the XRD spectroscopy and HR-TEM imaging. In contrast, substantial crystallization of PWA takes place when PWA/SiO2 particles are as large as 10 nm, in which case less amount of surface free Si-OH is available for PWA to make bonds with. Photochromism occurs activated by ultraviolet light irradiation. The rate of coloration/bleaching is found to depend strongly on the particle size of PWA/SiO2; specifically, the rate increases twice when the particle size is reduced from 10 nm to 1.2 nm. 相似文献
909.
A new three-matrix mixed vanadate crystal Nd:Lu0.33Y0.36Gd0.3VO4 (Nd:LuYGdVO4) crystal was grown by the Czochralski method. Room temperature absorption and fluorescence spectra of the Nd:LuYGdVO4 crystals were measured and the spectroscopic parameters were calculated by the Judd-Ofelt theory. The intensity parameters
of the Nd:LuYGdVO4 crystal were Ω2 = 9.736 × 10−20 cm2, Ω4 = 4.179 × 10−20 cm2, Ω6 = 8.020 × 10−20 cm2 and the stimulate emission cross section was 5.3 × 10−19 cm2. Diodepumped actively Q-switched and passively Q-switched Nd:LuYGdVO4 and Nd:Lu0.14Y0.86VO4 lasers at 1.06 μm were demonstrated. The results indicate that, for both actively and passively Q-switched lasers, the Nd:LuYGdVO4 lasers can generate shorter pulse width with higher peak power than the Nd:Lu0.14Y0.86VO4 lasers at the same cavity conditions. 相似文献
910.
We propose and experimentally demonstrate a novel subwavelength grating coupler on silicon-on-insulator, for coupling to optical fibers with a wide optical bandwidth. Theoretical analysis and design optimization of the coupler are described. About 73?nm 1?dB bandwidth was experimentally demonstrated with -5.6 dB coupling efficiency. Better than -3.4 dB efficiency with 86?nm 1?dB bandwidth is predicted for these structures with optimized buried oxide thickness. 相似文献