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51.
本文讨论了气体击穿、空间电行与温度的关系,给出了测定原子第一激发电位和电离电位曲线时选择温度应遵循的规律.  相似文献   
52.
对于高温高压下氩等离子体的电离度和物态方程,本文给出了一种基于Thomas-Feimi(TF)统计模型的简化计算新方法:首先将TF模型电离势的数值结果进行函数逼近,给出一个便于数值求解的计算电离度的近似计算方法,并由此计算了局部热动平衡下的氩等离子体在10~1000 eV高温范围内的物态方程.计算结果与国外报道的其他几种理论模型的计算结果均符合很好,与实验值也吻合较好.本文所提出的简单模型也适用于计算混合物物态方程,可以在电磁发射技术领域中的强电离等离子体中有更为广阔的应用前景.  相似文献   
53.
We study the equilibrium statistical mechanics of classical two-dimensional Coulomb systems living on a pseudosphere (an infinite surface of constant negative curvature). The Coulomb potential created by one point charge exists and goes to zero at infinity. The pressure can be expanded as a series in integer powers of the density (the virial expansion). The correlation functions have a thermodynamic limit, and remarkably that limit is the same one for the Coulomb interaction and some other interaction law. However, special care is needed for defining a thermodynamic limit of the free energy density. There are sum rules expressing the property of perfect screening. These generic properties can be checked on the Debye–Hückel approximation, and on two exactly solvable models, the one-component plasma and the two-component plasma, at some special temperature.  相似文献   
54.
The present study aims at antimicrobial polyethylene surfaces. To achieve this, LLDPE was compounded with the polymeric biocide poly(2-tert-butylaminoethyl) methacrylate TBAM (bulk modification with 1.5-5.0 wt.% of TBAM). Surfaces of these polymer compounds were then subjected to microbial assays. Using standard methods the colony forming units (CFU) for Escherichia coli and Staphylococcus aureus were determined on these surfaces. In all cases, polyethylene surfaces with highly antimicrobial properties were achieved. An average reduction of 104 CFU ml−1 compared to neat LLDPE was achieved. The surfaces of these LLDPE/TBAM compounds were assessed by electrokinetic (zeta potential) measurements. The results indicate a relation between the antimicrobial activity and the zeta-potential of the polymer compounds. Moreover, the antimicrobial compounds were investigated towards biofilm formation. Compared to pristine LLDPE, the surfaces of the polymer compounds showed less adhering biofilm after a testing period of 16 weeks.  相似文献   
55.
Summary The complete error potential is used for the study of the correlation of molecules. The correlation can be seen as a relaxation of the electrons and a relaxation of the nuclei. From the Fermi sea, the electronic relaxation gives rise to a partial excitation of each orbital which collectively generates a linear, a surface or a volume pressure; the resulting forces acting on the nuclei are defined in a general theory of the intramolecular forces. H3, H 3 + , the diatoms and the hydrid of the first nine elements are taken as examples.  相似文献   
56.
多电解质溶液中带电胶体粒子的电势分布由球形Poisson-Boltzmann方程(PBE)描述.PBE是一个非线性的微分方程,且难以求得其解析解.本文采用非线性P-B积分方程,计算电势分布的数值解.首先,根据静电场和热力学系统中的物理定理,导出描述电势分布的P-B积分方程(PBIE);其次,用迭代方法求PBIE的数值解.最后,计算了在3-1型电解液中无量纲半径κa分别为0.12和0.22,无量纲表面电势ξ分别为1,2,4,6时球形胶体粒子外部的电势值.为了检验数值解的精度,计算了表面电荷密度,并与Loeb(1961)和Oshima(1995)等人的结果比较,本文结果的相对误差小于1%,优于Oshima的结果.  相似文献   
57.
Polymer electrolyte systems were prepared for the first time by dissolution of amidomagnesium chlorides in poly(ethylene oxide), (PEO). For the preparation, solutions of (hexamethyldisilylamido)magnesium chloride, (dimethylpyrrolyl)magnesium chloride, (diisopropylamido)magnesium chloride, piperidinomagnesium chloride and morpholinomagnesium chloride were chosen. The composition of these polymer electrolyte systems corresponds to the general formula R2NMgCl·P(EO)n·THF. Most work has been done with the system (hexamethyldisilylamido)magnesium chloride in PEO, (Me3Si)2NMgCl·P(EO)n·THF, with n= 3, 4, 5, or 7. The electrolytes have a soft rubber-like consistency. At 30 °C, electrical conductivities of 10−6–10−5 S/cm were found. The conductivities were measured in the temperature range 20–60 °C. Within this temperature range a linear dependence of the logarithms of the conductivity on the inverse temperature was found and activation energies for the conducting process of 30–60 kJ/mol were calculated. Using those polymer electrolytes with a high content of the amidomagnesium compound, a reversible magnesium deposition takes place by cathodic reduction at potentials below −1.9 V vs. a Ag/AgCl reference electrode. These polymer electrolytes were found to be stable against oxidation up to about −0.3 V vs. Ag/AgCl. Electronic Publication  相似文献   
58.
The calculation of Franck–Condon factors between different 1‐D Morse potential eigenstates using a formula derived from the Wigner function is discussed. Our numerical calculations using a simple program written in Mathematica are compared with other calculations. We show that our results have a similar accuracy as those calculations performed with more sophisticated methods. We discuss the extension of our method to include non‐Condon effects in the calculation. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem 88: 280–295, 2002  相似文献   
59.
Application of multiple scattered-wave X_α method with overlapping atomic-sphere to ionization potentials is reported for benzene, pyridine, pyrazine, pyrrole and imidazole. The calculated results show that the orbital charges in the intersphere region are non-negative and the energy levels get improvements in orderings.  相似文献   
60.
从理论上研究了非骨架阳离子可能的分布位置.计算了分子筛晶体基本结构单元在整个空间的静电势分布,找出空间中静电势的各个极小点.在静电势最低点逐个放置钠离子,优化,重新计算模型分子筛的电势分布.研究了阳离子放置过程中静电势变化的趋势.  相似文献   
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