In this paper we calculate the transfer coefficients for evaporation and condensation of mixtures. We use the continuous profiles of various thermodynamic quantities through the interface, obtained in our previous works using the square gradient model. Furthermore we introduce the Gibbs surface and obtain the excess entropy production for a surface. Following the traditional non-equilibrium thermodynamic approach we introduce the surface transfer coefficients which we are able to determine from the continuous solution. The knowledge of these coefficients is important for many industrial applications which involve transport through a surface, such as for instance distillation. In our approach the values of the local resistivities in the liquid and the vapor phases are chosen on the basis of experimental values. In the interfacial region there are small peaks in these resistivities. Three amplitudes control the magnitude of these peaks. Possible values of these amplitudes are found by matching the diagonal transfer coefficients to values predicted by kinetic theory. Using these amplitudes we find that the value of the cross resistivities is 1-2 orders of magnitude higher then the one from kinetic theory. The results of both kinetic theory and molecular dynamics simulations support the existence of small peaks in the local resistivities in the interfacial region. The square gradient approach gives an independent way to determine the transfer coefficients for surfaces. The results indicate that kinetic theory underestimates the interfacial transfer coefficients in real fluids.
Adam-Gibbs Model for the Supercooled Dynamics in OTP-OPP Mixture
α-弛豫时间的介电测量进行邻-三联苯(OTP)与邻-苯基苯酚(OTP)的混合物,在两个压力,0.1和28.8 MPa的温度范围内。这些条件与Takahara等人报道的热容、热膨胀率和压缩性测量条件相同。Takahara,M.石川岛Yamamuro和T. Matsuo,Journal of Physical Chemistry B 103(16),3288(1999).]同样的混合物。从相结合的动力学和热力学数据,我们确定,密度和温度的弛豫时间随温度的变化在同等程度上。在整个测量范围内,弛豫时间对组态熵的依赖关系符合Adam-Gibbs模型,并且这种依赖关系不随压力变化。与松弛和热力学性质之间的隐含连接一致,动力学和热力学的脆弱性被发现具有相同的压力独立性。在将混合物的弛豫性质与纯OTP的弛豫性质进行比较时,密度效应在前者中更强,这可能暗示较低效率的堆积。
Using a minimal algebraic model for the thermodynamics of binary rod--polymer mixtures, we provide evidence for a quintuple phase equilibrium; an observation that seems to be at odds with the Gibbs phase rule for two-component systems. Our model is based on equations of state for the relevant liquid crystal phases that are in quantitative agreement with computer simulations. We argue that the appearance of a quintuple equilibrium, involving an isotropic fluid, a nematic and smectic liquid crystal, and two solid phases can be reconciled with a generalized Gibbs phase rule in which the two intri…
We study the competitive irreversible adsorption of a binary mixture of monomers and square-shaped particles of linear size $R$ on the square lattice. With the random sequential adsorption model, we investigate how the jamming coverage and percolation properties depend on the size ratio $R$ and relative flux $F$. We find that the onset of percolation of monomers is always lower for the binary mixture than in the case with only monomers ($R=1$). Moreover, for values $F$ below a critical value, the higher is the flux or size of the largest species, the lower is the value of the percolation thres…
We develop the rheology of a dilute granular gas mixture. Motivated by the interaction of charged granular particles, we assume that the grains interact via a square shoulder and well potential. Employing kinetic theory, we compute the temperature and the shear viscosity as functions of the shear rate. Numerical simulations confirm our results above the critical shear rate. At a shear rate below a critical value, clustering of the particles occurs.
Using the Fundamental-Measure Density Functional Theory, we have studied theoretically the phase behavior of extremely confined mixtures of parallel hard squares in slit geometry. The pore width is chosen such that configurations consisting of two consecutive big squares, or three small squares, in the transverse direction, perpendicular to the walls, are forbidden. We analyzed two different mixtures with edge-lengths of species selected so as to allow or forbid one big plus one small square to fit into the channel. For the first mixture we obtained first-order transitions between symmetric an…
A Unified Rational-Function Approximation for Square-Well, Square-Shoulder, and Nonadditive Hard-Sphere Mixtures
Universidad de Extremadura(埃斯特雷马杜拉大学);Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura(埃斯特雷马杜拉大学先进科学计算研究所);Instituto de Energías Renovables, U.N.A.M.(墨西哥国立自治大学可再生能源研究所)