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951.
An analytical expression for the phase shift contribution to the internal partition function for the Morse potential is derived
by using an approximate Jost function. This function is shown to be a convergent sum. The numerical results obtained for H2 and HCl show the partition function to be a monotonically increasing function of temperature. This observation agrees with
the results of Rogers and co-workers.
Work supported in part by the Department of Atomic Energy, Government of India. 相似文献
952.
953.
It is well-known that not all instances of the stable roommates problem admit a stable matching. Here we establish the first nontrivial upper bound on the limiting behavior of Pn, the probability that a random roommates instance of size n has a stable matching, namely, lim n→∞ Pn? e1/2/2 (=0.8244…). © 1994 John Wiley & Sons, Inc. 相似文献
954.
A simple model for the adsorption of gas molecules on fractal surfaces is formulated. For surface reactions where adsorption
is the rate determining step, considerations based on the probability of adsorption are sufficient to describe the kinetics.
Different values of fractal dimension correspond to different values of rate constant for adsorption. A linear relationship
between the dynamics and the geometric properties of a solid surface as well as a statistical mechanical relationship between
internal partition functions of the gas molecule and the adsorption complex are obtained. 相似文献
955.
Hoonjoo Kim Sung‐Jin Lee Hae‐Soo Oh 《Numerical Methods for Partial Differential Equations》2003,19(3):399-420
The method of auxiliary mapping (MAM), introduced by Babu?ka and Oh, was proven to be very successful in dealing with monotone singularities arising in two‐dimensional problems. In this article, in the framework of the p‐version of FEM, MAM is presented for one‐dimensional elliptic boundary value problems containing singularities. Moreover, in order to show the effectiveness of MAM, a detailed proof of an error estimate is also presented, which gives a sharp error bound of MAM. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 399–420, 2003. 相似文献
956.
Zoltán Aigner Ágnes Kézsmárki Mihály Kata Csaba Novák István Erös 《Journal of inclusion phenomena and macrocyclic chemistry》2002,42(3-4):227-233
Tenoxicam is a widely used non-steroidal anti-inflammatory drug (NSAID). Itscomplexation with cyclodextrin was studied in order to improve its aqueoussolubility and to decrease its side-effects. Two- and three-component systems inseveral mole-ratios were prepared by means of two different methods. The drugliberation profile, the in vitro membrane diffusion and the n-octanol/water partitioncoefficient were investigated. The presence of complexes was detected via thermoanalyticaland X-ray diffractometric studies. On the basis of these data, several compositionswere selected for incorporation into topical dosage forms. 相似文献
957.
特殊二元生成t-半群 总被引:1,自引:0,他引:1
邓明香 《纯粹数学与应用数学》2002,18(1):36-41
主要考虑了满足生成关系xy=x^2=yx,或者yx=y=yx的二元生成t-半群,给出了它的三个等价条件,并且定义了局部循环半群,可分半群,不可分半群,及条件P^*,条件A^*。从而给出循环半群的等价刻画。这些都可看作文[2]关于循环t-半群结论的推广。为使某些引理,命题或定理的作用更为明朗。本文还举出相应的例题来体现所述目的。 相似文献
958.
Ernesto Vallejo 《Linear algebra and its applications》2002,340(1-3)
Minimal matrices were introduced to give an algebraic characterization of sets of uniqueness, a notion of interest in Discrete Tomography. They have also been used to produce minimal summands in Kronecker products of complex irreducible characters of the symmetric group. In this paper, motivated by these two applications, we classify all minimal matrices of size 2×q. 相似文献
959.
The generalized Trotter formula is used to derive two different classical representations of the partition function of a one-dimensional fermion model. Shortchain calculations are used to study the corresponding approximants for the energy and specific heat. A Monte Carlo technique has been used to calculate the temperature-dependent properties of a chain of 64 sites. 相似文献
960.
F. Y. Wu 《Journal of statistical physics》1988,52(1-2):99-112
Elementary exposition is given of some recent developments in studies of graphtheoretic aspects of the Potts model. Topics discussed include graphical expansions of the Potts partition function and correlation functions and their relationships with the chromatic, dichromatic, and flow polynomials occurring in graph theory. It is also shown that the Potts model realization of these classic graph-theoretic problems provides alternate and direct proofs of properties established heretofore only in the context of formal graph theory. 相似文献