共查询到18条相似文献,搜索用时 78 毫秒
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针对最新发展的气-固界面作用物理模型,提出一种确定性计算方法.算法的核心是:针对离散速度空间分布函数,采用确定性算法计算出单轮气-固碰撞作用的散射核函数矩阵,并通过考虑吸引势阱作用和迭代累加多次气-固碰撞作用,物理地反映气体分子入射/反射速度分布函数在气-固界面上的变化.与现有基于Monte Carlo随机采样的实现方... 相似文献
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流-固界面波的激光激发与光偏转检测 总被引:1,自引:1,他引:0
基于光偏转原理,研制了可用于流-固界面波探测的光纤传感装置.在此基础上,建立了以调Q Nd∶YAG激光为流-固界面波激发光源的实验系统.实验上探测了激光在空气-铝、水-铝和酒精-铝等界面上激发的界面波波形.根据实验波形,算得在这三种界面上的泄漏Rayleigh波和Scholte波的速度分别为2889 m/s和339 m/s、2916 m/s和1512 m/s、2872 m/s和1184 m/s,此实验值与理论计算值相比,偏差小于5%. 相似文献
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针对目前国际上中子评价核数据库中没有n 12C反应在20MeV以上的第一、第二激发态非弹散射角分布数据的情况,利用最小二乘法给出了数据库中缺失的Legendre系数,并且能很好地符合现有的实验数据,从而使评价数据库的数据更加齐全,给出的信息更加完整。 相似文献
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Yu-Chen Shu Chiu-Yen Kao I-Liang Chern Chien C. Chang 《Journal of computational physics》2010,229(24):9246-9268
In this paper, we propose an augmented coupling interface method on a Cartesian grid for solving eigenvalue problems with sign-changed coefficients. The underlying idea of the method is the correct local construction near the interface which incorporates the jump conditions. The method, which is very easy to implement, is based on finite difference discretization. The main ingredients of the proposed method comprise (i) an adaptive-order strategy of using interpolating polynomials of different orders on different sides of interfaces, which avoids the singularity of the local linear system and enables us to handle complex interfaces; (ii) when the interface condition involves the eigenvalue, the original problem is reduced to a quadratic eigenvalue problem by introducing an auxiliary variable and an interfacial operator on the interface; (iii) the auxiliary variable is discretized uniformly on the interface, the rest of variables are discretized on an underlying rectangular grid, and a proper interpolation between these two grids are designed to reduce the number of stencil points. Several examples are tested to show the robustness and accuracy of the schemes. 相似文献
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This paper presents the physical properties of vacuum evaporated CdTe thin films with post-deposition thermal annealing. The thin films of thickness 500 nm were grown on glass and indium tin oxide (ITO) coated glass substrates employing thermal vacuum evaporation technique followed by post-deposition thermal annealing at temperature 450 °C. These films were subjected to the X-ray diffraction (XRD),UV-Vis spectrophotometer, source meter and atomic force microscopy (AFM) for structural, optical, electrical and surface morphological analysis respectively. The X-ray diffraction patterns reveal that the films have zinc-blende structure of single cubic phase with preferred orientation (111) and polycrystalline in nature. The crystallographic and optical parameters are calculated and discussed in brief. The optical band gap is found to be 1.62 eV and 1.52 eV for as-grown and annealed films respectively. The I–V characteristics show that the conductivity is decreased for annealed thin films. The AFM studies reveal that the surface roughness is observed to be increased for thermally annealed films. 相似文献
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The effect of vacuum polarisation on internal conversion coefficients is investigated for the nuclear charge numbersZ=26 andZ=80; it contributes less than one percent to the conversion rate. 相似文献
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Jun Sun 《Molecular physics》2013,111(19):2325-2332
The tangential momentum accommodation coefficient (TMAC), usually used in slip boundary conditions in micro-gas flows, is reported to be always less than unity and greatly influenced by temperature and the strength of gas–wall interactions. According to the definitions of accommodation coefficients, a proper statistical algorithm in non-equilibrium molecular dynamics method was described and verified. In planar Poiseuille gas flow in a smooth microchannel, the TMAC were calculated considering both the effects of temperature and gas–wall interaction. In the simulation processes, more gas molecules began to be adsorbed near walls under the condition of stronger gas–wall interaction and lower temperature. The gas adsorption resulted in a longer gas–wall interaction time so that the TMAC increased. While the gas–wall interaction became much stronger, more and more gas molecules were adsorbed to form an explicit layer above the wall. The full coverage of gas molecules on the wall prevented further adsorption; therefore the TMAC did not keep on increasing as the interaction strength continued to increase. Meanwhile, the normal momentum accommodation coefficient (NMAC) was also calculated according to the definition. In the isothermal flow, the average gas momentum normal to the wall was in complete accommodation with the wall, and the NMAC was almost unity in smooth micro channels. 相似文献
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Phase aberration compensation of digital holographic microscopy based on least squares surface fitting 总被引:1,自引:0,他引:1
Jianglei Di Jianlin Zhao Weiwei Sun Hongzhen Jiang Xiaobo Yan 《Optics Communications》2009,282(19):3873-3877
Digital holographic microscopy allows the numerical reconstruction of the complex wavefront of samples, especially biological samples such as living cells. In digital holographic microscopy, a microscope objective is introduced to improve the transverse resolution of the sample; however a phase aberration in the object wavefront is also brought along, which will affect the phase distribution of the reconstructed image. We propose here a numerical method to compensate for the phase aberration of thin transparent objects with a single hologram. The least squares surface fitting with points number less than the matrix of the original hologram is performed on the unwrapped phase distribution to remove the unwanted wavefront curvature. The proposed method is demonstrated with the samples of the cicada wings and epidermal cells of garlic, and the experimental results are consistent with that of the double exposure method. 相似文献