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用高密度等离子体模型可以计算出一整套输运参数,并且在很宽的等离子体温度和密度范围内有合理的精度,可广泛应用于Z箍缩等离子体、激光聚变和磁约束聚变等领域,并将这个模型计算出的各种输运参数拟合成了实用的公式。     

Study of photon-induced L3 vacancy alignment for elements La to U

Alignment of photon-induced L₃ vacancies is studied in rare earth and highZ elements at energies of experimental interest, near thresholds to 60 keV, under nonrelativistic dipole approximation. Numerical calculations of the matrix element are undertaken to produce theoretical data for comparison with the experimental findings. The A₂ values being s>0.1 at photoelectron energies <20 keV are certainly higher than 5–8% uncertainties quoted in experimental results. Present findings are from a very basic model, hydrogen-like and can further be treated as reference to observe the impact of screening, relativistic, multipole and retardation corrections to the model     

A Particle-Mesh Method for the Shallow Water Equations Near Geostrophic Balance

In this paper we outline a new particle-mesh method for rapidly rotating shallow water flows based on a set of regularized equations of motion. The time-stepping method uses an operator splitting of the equations into an Eulerian gravity wave part and a Lagrangian advection part. An essential ingredient is the advection of absolute vorticity by means of translated radial basis functions. We show that this implies exact conservation of enstrophy. The method is tested on two model problems based on the qualitative features of the solutions obtained (i.e., dispersion or smoothness of potential vorticity contours) as well as on the increase in mean divergence level.     

三维Minkowski空间中的曲面及其可积性

利用可积系统的思想,借助三维Minkowski空间L3的矩阵模型,研究了L3中具有调和逆平均曲率的类空曲面和洛伦兹调和逆平均曲率类时曲面的可积性及其形变.     

A Criterion for Spectrum Decomposition

We obtain a necessary and sufficient condition for the decomposition of the spectrum of an arbitrary nonsymmetric potential whose least value is attained at finitely many points.     

Band bending at the Si(1 1 1)–SiO2 interface induced by low-energy ion bombardment

Experiments employing photoreflectance spectroscopy have uncovered band bending due to electrically active defects at the Si(1 1 1)–SiO₂ interface after sub-keV Ar⁺ ion bombardment. The band bending of about 0.5 eV resembles that for Si(1 0 0)–SiO₂, and both interfaces exhibit two kinetic regimes for the evolution of band bending upon annealing due to defects healing. The healing takes place about an order of magnitude more quickly at the (1 1 1) interface, however, probably because of less fully saturated bonding and higher compressive stress.     

微分电位溶出法测定酒中痕量铅

本文研究了测定酒中痕量铅的微分电位溶出法。该法检测下限为0.1ug·L~(-1)pb,在0～10ug·L~(-1)浓度范围内有良好线性关系,用于酒中痕量铅的直接测定,其相对标准偏差小于4.5%,回收率为98.5～103%,结果令人满意。     

Electrochemical reduction of 1,1-dihalo-2,2-disubstituted cyclopropanes

The electrochemical reduction of 1,1-dihalo-2-R-2-methylcyclopropanes was studied by polarography and preparative electrolysis. A mixture of stereoisomeric monoboro- and monochlorocyclopropanes was obtained with preparative yield of 60–70% in preparative electroreduction in methanol against a background of 0.1 M LiClO₄. In the case of bromine derivatives of cyclopropanes (except when R = CN) an effect was found on the part of the current density on the ratio of cis and trans isomers, which was interpreted as a change, in dependence on current density, of the contributions of the reactions of reduction of the starting compounds (S_N2 mechanism) and ionic pairs (S_N1 mechanism). The effect of the solvent (CHCl₃, DMF, DMSO, MeOH) and background salt (LiClO₄, Et₄NBr) on the ratio of stereoisomers is in agreement with this interpretation.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, Kazan. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2023–2032, September, 1992.     

像势对量子阱中类氢杂质结合能的影响

在有效质量近似下，利用变分方法研究了像势对量子阱中类氢杂质结合能的影响。计算中考虑到了阱和垒中电子有效质量的不同。数值计算结果表明：阱和垒中质量的不连续只对阱宽较窄的区域有影响，而像势则在整个区域都有影响．对于阱和垒中介电常数之比较大和阱宽较小的量子阱，考虑像势对阱中杂质结合能的修正是非常必要的     

高压下氢化锂晶体中的离子间力与结合能公式的原子分子设计

本文提出一种利用材料Hugoniot数据研究高压下离子晶体中微观离子状态及其离子间排斥作用势的新方法。对氢化锂晶体进行研究时,我们得到Li~+和H~-离子之间排斥作用势函数,结果表明文献〔1〕中提出的离子压缩效应具有客观性。