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101.
采用密度泛函的B3P86方法,以6-311+G(3df)为基函数优化得到不同外电场下FO基态分子的稳定几何结构、键长、总能量、HOMO能级、LUMO能级、费米能级、能隙、红外光谱和谐振频率.结果表明,分子结构与外电场有着强烈的依赖关系,且对电场方向的依赖呈现出不对称性;随着正向电场的增大,HOMO能级、LUMO能级和费米能级是减小的,能隙是先增大后减小;红外光谱和谐振频率是增大的,而频率间隔是不断减小的. 相似文献
102.
《Mathematical Methods in the Applied Sciences》2018,41(1):317-335
This paper is focused on following time‐harmonic Maxwell equation: where is a bounded Lipschitz domain, is the exterior normal, and ω is the frequency. The boundary condition holds when Ω is surrounded by a perfect conductor. Assuming that f is asymptotically linear as , we study the above equation by improving the generalized Nehari manifold method. For an anisotropic material with magnetic permeability tensor and permittivity tensor , ground state solutions are established in this paper. Applying the principle of symmetric criticality, we find 2 types of solutions with cylindrical symmetries in particular for the uniaxial material. 相似文献
103.
Existence of ground state solutions for Kirchhoff‐type problems involving critical Sobolev exponents
《Mathematical Methods in the Applied Sciences》2018,41(1):371-385
In this paper, we study the existence of ground state solutions for a Kirchhoff‐type problem in involving critical Sobolev exponent. With the help of Nehari manifold and the concentration‐compactness principle, we prove that problem admits at least one ground state solution. 相似文献
104.
This paper is concerned with the existence and asymptotical behavior of positive ground state solutions for a class of critical quasilinear Schrodinger equation.By using a change of variables and variational argument,we prove the existence of positive ground state solution and discuss their asymptotical behavior。 相似文献
105.
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107.
考虑一个特殊的非线性奇偶对称模型,研究相关的基态光学模式,并通过功率和复折射率虚部的振幅之间的依赖关系来直观地判断光学模式的稳定性,这对理解和掌握奇偶对称复折射率分布波导中的光传输特性具有非常重要的实际意义. 相似文献
108.
The performance of a domestic heat pump that uses a low quantity of propane as refrigerant has been experimentally investigated. The heat pump consists of two minichannel aluminium heat exchangers, a scroll compressor, and an electronic expansion valve. It was charged with the minimum amount of refrigerant propane required for the stable operation of the heat pump without permitting refrigerant vapor into the expansion valve at incoming heat source fluid temperature to the evaporator of +10°C. The inlet temperature of the heat source fluid passing through the evaporator was varied from +10°C to ?10°C while holding the condensing temperature constant at 35°C, 40°C, 50°C, and 60°C, respectively. The minimum refrigerant charges required at above-tested condensing temperatures were found to decrease when the condensing temperature increased and were recorded as 230 g, 224 g, 215 g, and 205 g, respectively. The results confirm that a heat pump with 5 kW capacity can be designed with less than 200 g charge of refrigerant propane in the system. Due to the high solubility of propane in compressor lubrication oil, the amount of refrigerant which may escape rapidly in case of accident or leakage is less than 150 g. 相似文献
109.
Klaus Wittmaack 《辐射效应与固体损伤》2013,168(1-4):205-218
The present state of the art of secondary ion mass spectrometry (SIMS), applied to the in-depth analysis of impurity concentration profiles, is reviewed critically. It is shown that SIMS has reached a level of perfection which is unparalleled by other analytical techniques. There are, however, several effects which may cause deviations of the measured profile from the original dopant distribution. These detrimental effects are due to interaction of primary ions with the residual gas, adsorption and incorporation of residual gases, sputtering yield variations due to the accumulation of probe atoms in the sample, mass interference between molecular ions and the atomic species under study and, last but not least, beam-induced relocation of dopant atoms (“atomic mixing”). Methods for minimizing the respective disturbing effect are discussed. 相似文献
110.