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151.
152.
153.
Yuriy K. Tovbin 《Adsorption》2005,11(3-4):245-257
The equilibrium distribution and the concentration dependence of the local and average self-diffusion coefficients for pure
fluid and binary mixture components in narrow slitlike pores were analyzed. The coefficients were calculated using the lattice
gas model in the quasi-chemical approximation on the assumption of a spherical shape and approximately equal sizes of the
components. For the pure adsorbate, these calculations were compared with molecular dynamics simulations. Both methods gave
similar concentration profile changes and dynamic characteristics of interlayer particle redistributions in strong nonuniform
adsorption fields for dense fluids. A satisfactory agreement was obtained for the temperature dependences of the self-diffusion
coefficients along the pore axis. The influence of the molecule–wall potential and of intermolecular interaction were considered.
The self-diffusion coefficients of the adsorbate were shown to strongly depend on the density of the mixture and the distance
from pore walls. 相似文献
154.
提出一个用于电磁内爆过程数值模拟的准一维模型,对1 MJ电容器组电磁内爆优化方案进行了计算,并将计算结果与零维模型和一维模型的结果进行了比较。 相似文献
155.
Theoretical equations were proposed to adequately simulate the electrical conductivity behavior of aqueous solutions of both
charged and uncharged polymers. The theory, based on the mixture equation of Boned and Peyrelasse, was experimentally verified
on poly(acrylic acid) (PAA) in water and poly(ethylene oxide) (PEO) in aqueous electrolyte solutions. The data analysis suggested
that both the polymer coils may be depicted as oblate ellipsoids. Subsequently, the semiaxes values of the polymer coils were
determined, and they were in good agreement with the results reported in the literature.
Received: 25 June 1996 Accepted: 2 October 1996 相似文献
156.
We consider a continuum model describing steady flows of a miscible mixture of two fluids. The densities ϱ
i
of the fluids and their velocity fields u
(i) are prescribed at infinity: ϱ
i
|∞ = ϱ
i∞ > 0, u
(i)|∞ = 0. Neglecting the convective terms, we have proved earlier that weak solutions to such a reduced system exist. Here we
establish a uniqueness type result: in the absence of the external forces and interaction terms, there is only one such solution,
namely ϱ
i
≡ ϱ
i∞, u
(i) ≡ 0, i = 1, 2.
This work was supported by the SFB 611 at the University of Bonn and the European HYKE network (contract no. HPRN-CT-2002-00282).
The third author was also supported by the project CSF 201/03/0934, and by MSM 0021620839. 相似文献
157.
158.
聚乙烯醇/壳聚糖共混膜优先透醇性能的研究 总被引:8,自引:1,他引:7
聚乙烯醇/壳聚糖共混膜优先透醇性能的研究王新平,沈之荃,张富尧,林荣轩(浙江大学高分子系,化学系,杭州,310027)关键词渗透蒸发,聚乙烯醇/壳聚糖共混物膜,乙醇水溶液本文首次报道利用亲水性的聚乙烯醇和壳聚糖制得具有很高的乙醇优先透过选择性的透醇型... 相似文献
159.
Paul Marriott 《Annals of the Institute of Statistical Mathematics》2007,59(1):95-110
Local mixture models have proved useful in many statistical applications. This paper looks at ways in which the local assumption,
which is used in an asymptotic approximation, can be relaxed in order to generate a much larger class of models which still
have the very attractive geometric and inferential properties of local mixture models. The tool used to develop this large
class of models is the Karhunen–Loève decomposition. Computational issues associated with working with these models are also
briefly considered. 相似文献
160.
Jõgi Henna 《Annals of the Institute of Statistical Mathematics》1985,37(1):235-240
Summary Suppose thatH is a mixture of distributions for a given familyF A necessary and sufficient condition is obtained under whichH is, in fact, a finite mixture. An estimator of the number of distributions constituting the mixture is proposed assuming
that the mixture is finite and its asymptotic properties are investigated. 相似文献