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151.
152.
混合工质变浓度空调系统动态特性的模拟   总被引:1,自引:0,他引:1  
本文在分析混合工质变浓度空调系统的传热传质和参数间的相互耦合关系的基础上,以实际流体的质量、动量和能量守恒方程为基础,结合系统各部件的特点,分别建立了各部件的数学模型,并实现了对系统动态特性的模拟计算和分析。  相似文献   
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.
 提出了描述混合物固液相变的两个近似模型:混合相模型和等效物质模型。通过对304钢的计算和比较表明,由两个模型计算得到的结果与直接利用304钢的材料参数计算得到的结果相符合。  相似文献   
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.
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.
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   
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