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81.
电子离子碰撞激发速率系数在超组态碰撞辐射模型中真实模拟非局域热动力学平衡Au激光等离子体M带谱 5f 3d跃迁中各种复杂电荷态离子的电离态特性 (譬如离子的平均电离度 ,相对丰度和能级布居数 )是必不可少的。基于准相对论多组态Hartree Fock方法和扭曲波玻恩交换近似 ,采用自编的扭曲波程序ACDW (9)和Fit(9) ,从头计算了Au等离子体M带 5f 3d电子离子碰撞激发速率系数。结果表明 :在“神光II”实验装置诊断的电子温度约 2keV ,电子密度约 6× 10 2 1cm-3 范围内 ,这些电子离子碰撞激发参数有利于采用超组态碰撞辐射模型模拟Au的激光等离子体M带 5f~ 3d细致谱的平均电离度和电荷态分布。  相似文献   
82.
本文从速率方程出发,讨论了类锂铝复合等离子体的激发态结构,衰减常数,反转率和小信号增益等表征介质增益特性的物理量以及它们随电子温度,电子密度和光子逃逸几率的变化。找到了进行类锂铝离子通过复合机制产生X光激光设计应创造的等离子体状态目标区域。还讨论了这些物理量随原子序数变化的定标律。  相似文献   
83.
Entropy production per site in a (nonreversible) spin-flip process is studied. We give it a useful expression, from which a property stronger than affinity of the entropy production per site follows. Furthermore, quasi-invariance of nonequilibrium measures in the spin-flip processes is discussed via entropy production.  相似文献   
84.
聚丙烯微孔膜的等离子体接枝聚合改性   总被引:2,自引:1,他引:1  
利用拉伸时的晶型转变致孔特性,从β晶相聚丙烯经单向或双向拉伸制得了新型聚丙烯微孔膜、用等离子体接枝聚合技术接上了亲水性聚合物如聚丙烯酸、聚丙烯腈等。研究了等离子体处理时间、单体性质对得到的亲水膜的亲水性、离子/溶质渗透性的影响。发现接枝聚丙烯酸的双向拉伸膜对Na~+、Mg~(++),尿素有较大的渗透性,并具有优良的形状稳定性。  相似文献   
85.
X-ray absorption spectra of plasmas   总被引:1,自引:0,他引:1  
In this paper we present a theoretical method to calculate the absorption spectra of hot dense plasmas. Based on our fully relativistic treatment incorporated with the quantum defect theory to handle the huge number of transition arrays from many configurations with high principal quantum number, we can calculate the absorption spectra for any element or multi-element plasmas with little computational efforts. We calculate the absorption spectra of C10H1605 plasmas, which are in good agreement with the experimental spectra. We can then provide diagnostic analysis for plasmas in relevant inertial confinement fusion (lCF) experiments; namely not only to determine plasmas' temperatures and densities, but also to provide the population densities of various ionic stages. Our theoretical method verified by "benchmark experiments" will be a basic tool to provide "precise" opacity data for the ICF research.``  相似文献   
86.
A quick sample preparation method was used for the determination of sulphur and trace metals in oil and oily products by the ICP with a minitorch. Stable aqueous emulsions of oils and oil products were made by using two kinds of emulsifiers (one with low sulphur content, the other sulfonated). Aqueous standard solutions can be used for the preparation of calibration solutions. The contents of S, Al, Cr, Cu, Fe, Mg, Ni and Pb in aqueous emulsions were determined and the results were in good agreement with the composition of oil standard solutions used for control analysis procedure.  相似文献   
87.
We have investigated the effect of the surface state and surface treatment of the pores of an inorganic substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes. Shirasu porous glass (SPG) was used as the inorganic substrate, and methyl acrylate was used as the grafting monomer. The grafting rate increased as the density of silanol on the SPG substrate increased. This result suggests that radicals are generated mainly at the silanol groups on the pore surface by plasma irradiation. The SPG substrates were treated with silane coupling agents used to control the mass of organic material bonded to the pore surface. The thickness of the grafted layer became thinner as the mass of organic material bonded to the pore surface of SPG increased. This decrease in the thickness of the grafted layer could be explained by the decrease in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of the grafted layer inside the SPG substrates could be controlled through the control of the mass of organic material bonded to the pore surface of the SPG substrate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 846–856, 2006  相似文献   
88.
This study describes the preparation of polyethersulfone (PES)/layered silicate nanocomposites (PLSNs) by mixing PES polymer chain into organically‐modified layered silicate in 1‐methyl‐2‐pyrrolidinone (NMP) solution. Both X‐ray diffraction data and transmission electron microscopy images of PLSNs indicate that the silicate layers were almost exfoliated and randomly distributed into the PES matrix. The mechanical and barrier properties of PLSNs show remarkable enhancement in the storage modulus and water/oxygen permeability when compared with that of neat PES matrix. Surfaces modification of PES and PLSN films with various treated times, system pressures, and radio frequency (RF) powers were performed using a mixture of oxygen (O2) and nitrogen (N2) plasmas. The topographical and physical properties of plasma‐modified PES and PLSN surfaces were investigated using scanning probe microscopy (SPM), contact‐angle measurements, and X‐ray photoelectron spectroscopy (XPS). These results indicate that the surface roughness of PLSNs with the same condition of plasma modification is lower than that of neat PES matrix and is probably due to the increase of stiffness with the presence of inorganic layered silicates in PES matrix. The surface properties of the PES and PLSNs are also changed from hydrophobic to hydrophilic. The XPS spectra suggest that the exposure of the PES and PLSNs to the plasmas led to the combination of etching reactions of polymer surface initiated by plasma and the following addition reactions of new oxygen‐ and nitrogen‐containing functional groups onto polymer surfaces to change their surface properties. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3185–3194, 2006  相似文献   
89.
The dynamics of the electric arc inside a direct current non-transferred arc plasma torch are simulated using a three-dimensional, transient, equilibrium model. The fluid and electromagnetic equations are solved numerically in a fully coupled approach by a multiscale finite element method. Simulations of a torch operating with argon and argon–hydrogen under different operating conditions are presented. The model is able to predict the operation of the torch in steady and takeover modes without any further assumption on the reattachment process except for the use of an artificially high electrical conductivity near the electrodes, needed because of the equilibrium assumption. The results obtained indicate that the reattachment process in these operating modes may be driven by the movement of the arc rather than by a breakdown-like process. It is also found that, for a torch operating in these modes and using straight gas injection, the arc will tend to re-attach to the opposite side of its original attachment. This phenomenon seems to be produced by a net angular momentum on the arc due to the imbalance between magnetic and fluid drag forces.  相似文献   
90.
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