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排序方式: 共有58条查询结果,搜索用时 15 毫秒
41.
Measurement and interpretation of electrokinetic phenomena 总被引:1,自引:0,他引:1
42.
Hafeez Ur-Rehman 《中国物理 B》2013,(3):370-375
Using the reductive perturbation method,we have derived the Kadomtsev-Petviashvili(KP) equation to study the nonlinear properties of electrostatic collisionless dust ion-acoustic solitons in pair-ion(p-i) plasmas.We have chosen the fluid model for the positive ions,the negative ions,and a fraction of static charged(both positively and negatively) dust particles.Numerical solutions of these dust ion-acoustic solitons are plotted and their characteristics are discussed.It is found that only the amplitudes of the electrostatic dust ion-acoustic solitons vary when the dust is introduced in the pair-ion plasma.It is also noticed that the amplitude and the width of these solitons both vary when the thermal energy of the positive or negative ions is varied.It is shown that potential hump structures are formed when the temperature of the negative ions is higher than that of the positive ions,and potential dip structures are observed when the temperature of the positive ions supersedes that of the negative ions.As the pair-ion plasma mimics the electron-positron plasma,thus our results might be helpful in understanding the nonlinear dust ion acoustic solitary waves in super dense astronomical bodies. 相似文献
43.
A variety of alkyl-arenes and cyclohexane were converted to the corresponding ketones with NaCIO as the oxidant in the presence of l-glycyl-3-methyl imidazolium chloride-copper(Ⅱ) complex.This method contains simplified product isolation and catalyst recycling,affording benzylic C-H oxidation of alkyl-arenes imparting high yield of ketones.Furthermore,complex could be reused seven times without a significant loss of its catalytic activity. 相似文献
44.
<正>Second harmonic generation(SHG) results from molecules which are polarized by an external electric field often provided by an intense laser beam.The polarizability depends on firstly the intrinsic structural properties of the substance and hence the second-order nonlinear susceptibility,and secondly the intensity and polarization direction of the incident light.The polarization characteristics of the beam are therefore of interest.In this letter,we discuss some considerations in SHG microscopy of collagen when the incoming beam is circularly polarized,and present some supporting results as well as a numerical analysis.We propose a quasi-crystal model of collagen microstructure in an effort to further our understanding on this protein. 相似文献
45.
We propose a method for exaggerating facial expressions derived from exaggeration mappings that transform facial motions into exaggerated motions. The exaggeration mapping of facial motions is defined by non-negative matrix factorization. Three-dimensional facial expressions are simulated using the exag- gerating rate as an input value to convey the degree of variation. Experiments show the validity of the exaggeration mapping and facial expression simulations. 相似文献
46.
TENSILE STRENGTH FOR SPLITTING FAILURE OF BRITTLE PARTICLES WITH CONSIDERATION OF POISSON''''S RATIO
Guoming Hu* Yanmin Wang Pingbo Xie Zhidong Pan Division of Powder & Particle Technology College of Materials Science Engineering South China University of Technology Guangzhou P. R. China *Author to whom correspondence should be addressed. E-mail: hu_guoming@hotmail.com 《中国颗粒学报》2004,2(6)
1. Introduction The core mechanism of comminution could be reduced to the breakage of individual particles that occurs through contact with other particles or with the grinding media, or with the solid walls of the mill (Potapov & Campbell, 1994). When a particle is subjected to a load, the nature of the stress field around and within the brittle particle, its material properties, and the size and distribution of micro-flaws within the particle govern the size and shape distribution of the fra… 相似文献
47.
弹性功能梯度材料板条中周期裂纹的反平面问题 总被引:1,自引:0,他引:1
讨论了弹性功能梯度材料板条中裂纹的反平面问题. 用Fourier
变换方法得到了一个基本解. 这个基本解表示了实轴上一点作用有点位错时引起的影响. 利
用此基本解可得单裂纹和周期裂纹问题的奇异积分方程. 在周期裂纹求解时,
远处裂纹对于中央裂纹的影响作了有效的近似处理. 最后, 给出了数值结果,
它表示了材料性质对于裂纹端应力强度因子的影响. 相似文献
48.
49.
Preparation of iron oxide ( -Fe 2 O 3 ) nanoparticles was carried out via a sonochemical process. The process parameters such as temperature, sonication time and power of ultrasonication play important roles in the size and morphology of the final products. The iron oxide nanoparticles were characterized by transmission electron microscopy, X-ray powder diffraction, and thermogravimetric and differential thermal analyses. From transmission electron microscopy observations, the size of the iron oxide nanopar... 相似文献
50.
将多电子原子、离子模型势理论(WBEPM)处理方式加以推广,讨论等电子系成员的基态和激发态能量差的规律性,并具体研究了类氖等电子系成员的各激发态能级结构,结果与其它计算值进行了比较。 相似文献