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991.
992.
The correlation-polarization (CP) model-potential, given by O’Connell and Lane (1983) as well as Padial and Norcross (1984)
is examined for the elastic scattering of electrons by oxygen atoms, at intermediate energies. The correlation potential is
found to be stronger than necessary at low energies. Two model polarization potentials based on the CP model, are suggested
and employed to thee
− — O scattering at 8.7, 30, 50 and 100 eV energies. The calculated total cross-sections agree in general with the other data
at these energies. 相似文献
993.
994.
We propose a general model for describing the phenomena of phase coexistence in relation to pressure induced phase transformations by means of the T–P distribution in statistical thermodynamics. Using the well‐known B1–B2 transition in NaCl as a prototype, we demonstrate how phase coexistence gives rise to the changes in the bulk modulus and the equation‐of‐state across the transition. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
995.
A. A. Zazhogin A. P. Zazhogin A. I. Komyak A. I. Serafimovich 《Journal of Applied Spectroscopy》2003,70(4):588-592
Based on an analysis of the low-temperature luminescence spectra of tri- and tetranitrate uranyl compounds, the influence exerted by the nature of outer-sphere cations (Na, K, Rb, NH4, and Cs) on the position of a purely electron transition in the uranyl ion has been studied. Linear correlation dependences of the position of a purely electron transition on the value of the ionization potential of cations have been established. It is shown that the upper occupied molecular orbital, whose position is determined by the total donating capacity of ligands and their number, is essentially of ligand character. 相似文献
996.
We have treated the Hulthén-modified separable potentials within the framework of the phase-function method and obtained a
closed form expression fors-wave scattering phase shift. Specializing to a rank one separable potential we have found out the limiting conditions in
which the Hulthén-modified phase shift goes over to its Coulomb counterpart. We demonstrate the usefulness of our approach
by means of a model calculation.
Based in part on a Ph.D. thesis to be submitted by one of the authors (AKJ) to Visva-Bharati University. 相似文献
997.
Stephan Dahlke 《manuscripta mathematica》1998,95(1):59-77
This paper is concerned with some theoretical foundations for adaptive numerical methods for elliptic boundary value problems.
The approximation order that can be achieved by such an adaptive method is determined by certain Besov regularity of the weak
solution. We study Besov regularity for second order elliptic problems in bounded domains in ℝ
d
. The investigations are based on intermediate Schauder estimates and on some potential theoretic framework. Moreover, we
use characterizations of Besov spaces by wavelet expansions.
This work has been supported by the Deutsche Forschungsgemeinschaft (Da 360/1-1) 相似文献
998.
Jeannette H. A. M. Wonders Herman P. Van Leeuwen Johannes Lyklema 《Colloids and surfaces. A, Physicochemical and engineering aspects》1997,120(1-3):221-233
The cadmium binding properties of a core-shell latex were investigated using differential pulse polarography. The latex particles have a polystyrene core which is surrounded by a hydrophilic shell containing a low density of sulphonic and carboxylic groups. For this core-shell latex dispersion, the binding of protons and metal ions can be analyzed reasonably well using Donnan's potential model [J.T. Davies and E.K. Rideal, Interfacial Phenomenon, Academic Press, New York, 1961]. However, the correction of Ohshima and Kondo [H.O. Ohshima and T. Konda, Biophys. Chem., 39 (1991) 181] of the Donnan model for the distribution of ions in the double layer near and in the shell is a real improvement. In this way, the binding constants of cadmium(II)with the surface groups of latex were separated into their intrinsic and electrostatic parts. The intrinsic constant for binding of cadmium(II) to carboxylic groups, obtained in this way, was similar to literature values. 相似文献
999.
Two approximate methods for calculating singular integrals appearing in the numerical solution of three-dimensional potential flow problems are presented. The first method is a self-adaptive, fully numerical method based on special copy formulas of Gaussian quadrature rules. The singularity is treated by refining the partitions of the copy formula in the vicinity of the singular point. The second method is a semianalytic method based on asymptotic considerations. Under the small curvature hypothesis, asymptotic expansions are derived for the integrals that are involved in the calculation of the scalar potential, the velocity as well as the deformation field induced from curved quadrilateral surface elements. Compared to other methods, the proposed integration schemes, when applied to practical flow field calculations, require less computational effort. 相似文献
1000.
陈华鹏 《宁波大学学报(理工版)》1990,(1)
假定位移场,并将位移势函数展开成一系列的特征函数,代入空间轴对称变形的基本方程,推得界面裂纹的特征值理论。把这一理论应用到单向增强的连续纤维复合材料上,建立了纤维断裂、基体开裂等模型下应力奇异性的特征方程,分析了界面裂纹尖端的应力奇异性。 相似文献