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991.
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
992.
A.P. Seitsonen D. Crihan M. Knapp A. Resta E. Lundgren J.N. Andersen H. Over 《Surface science》2009,603(18):L113-L116
Combining state-of-the-art density functional theory (DFT) calculations with high resolution core level shift spectroscopy experiments we explored the reaction mechanism of the ammonia oxidation reaction over RuO2(1 1 0). The high catalytic activity of RuO2(1 1 0) is traced to the low activation energies for the successive hydrogen abstractions of ammonia by on-top O (less than 73 kJ/mol) and the low activation barrier for the recombination of adsorbed O and N (77 kJ/mol) to form adsorbed NO. The NO desorption is activated by 121 kJ/mol and represents therefore the rate determining step in the ammonia oxidation reaction over RuO2 (1 1 0). 相似文献
993.
WANG Yue-Yue DAI Chao-Qing ZHANG Jie-Fang 《理论物理通讯》2009,51(1):81-89
In this paper, exact and numerical solutions are calculated for discrete complex Ginzburg-Landau equation with initial condition by considering the modified Adomian decomposition method (mADM), which is an efficient method and does not need linearization, weak nonlinearity assumptions or perturbation theory. The numerical solutions are also compared with their corresponding analytical solutions. It is shown that a very good approximation is achieved with the analytical solutions. Finally, the modulational instability is investigated and the corresponding condition is given. 相似文献
994.
** Email: julius.kaplunov{at}brunel.ac.uk Explicit models for the Rayleigh and BleusteinGulyaevsurface waves are extracted from the original 2D formulationswithin the general framework of linear elasticity and electroelasticity.The derivations are based on perturbing in slow time the self-similarsolutions for homogeneous surface wave. Both the proposed modelsinvolve hyperbolic equations on the surface along with ellipticequations over the interior, emphasizing the dual nature ofa surface wave. Comparisons with exact solutions are presented,including that for the plane Lamb problem. 相似文献
995.
研究了半结晶聚合物交联聚乙烯的聚集态和陷阱等对真空沿面闪络特性的影响.交联聚乙烯(XLPE)在135℃下恒温10min后,分别经过-56℃,-25℃淬火处理,自然降温,或1℃/min,0.5℃/min慢速降温等热处理过程,测量了热处理后试样的电气性能、显微结构、陷阱分布和真空中的沿面闪络特性.实验结果表明,与未热处理试样相比,热处理试样的直流闪络电压最高提高了76%,脉冲闪络电压最高提高了19%.认为热处理改变了XLPE试样的聚集态和陷阱,从而提高了XLPE试样的真空沿面闪络性能,提出了可以通过控制半结晶聚合物的聚集态和缺陷结构提高其真空沿面闪络性能. 相似文献
996.
997.
998.
Kuan-Wen Wang 《Applied Surface Science》2009,255(11):5802-5805
A series of PdxNi100−x nanoparticles were prepared by the co-precipitation method and analyzed using a temperature-programmed surface reaction (TPSR) of their methanation reactions. ESCA measurement suggested that the as-prepared Pd-Ni alloys had Pd-core/Ni-shell structure. Surface Pd segregation occurred during H2 reduction and resulted in a surface composition close to the nominal value. The TPSR experiments were performed by pre-adsorption of CO with H2 to form methane. The peak temperature of methanation increased as Pd content increased, indicating that a methanation reaction is favored on Ni and Ni-rich alloy nanoparticles. For physical mixtures of Pd and Ni nanoparticles, methanation behaviors is similar to those of alloy nanoparticles; but the methanation temperatures of physical mixtures are always higher than those of alloy nanoparticles. This may be due to the formation of a Pd-enriched alloy surface layer during reduction in H2 at 400 °C, or because the CO molecules adsorbed on the Pd sites spill over onto the Ni sites for methanation. Using TPSR technique and measuring methanation temperature, the top-most surface of such bimetallic nanoparticles can be probed. 相似文献
999.
Sigurd Angenent 《数学学报(英文版)》2008,24(12):1949-1952
Given a symmetric Finsler metric on T^2 whose geodesic flow has zero topological entropy, we show that the lift in the universal covering R^2 →T^2 of any closed geodesic on T^2 must be an embedded curve in R^2. 相似文献
1000.
This paper reports that an experimental investigation of fast pitch angle scattering(FPAS) of runaway electrons in the EAST tokamak has been performed.From the newly developed infrared detector(HgCdTe) diagnostic system,the infrared synchrotron radiation emitted by relativistic electrons can be obtained as a function of time.The FPAS is analysed by means of the infrared detector diagnostic system and the other correlative diagnostic systems(including electron-cyclotron emission,hard x-ray,neutrons).It is found that the intensity of infrared synchrotron radiation and the electron-cyclotron emission signal increase rapidly at the time of FPAS because of the fast increase of pitch angle and the perpendicular velocity of the energetic runaway electrons.The Parail and Pogutse instability is a possible mechanism for the FPAS. 相似文献