流体的传递性质如扩散系数和导热系数等，是化工冶金、环境化工、生物化工以及核工业过程的工艺设计所必需的数据，另外对传递性质的研究也有助于人们对物质的微观作用力及微观结构的认识。本文根据现有的统计力学理论对流体的导热系数和扩散系数进行理论研究和数据关联，为各种工业过程的工艺设计及计算提供基础数据。在流体导热系数研究方面，以方阱模型为基础，提出了液体导热系数的计算方程，该方程包括分子平动贡献项和分子内部能量贡献项两部分。同时，为了计算方便，根据分子模拟数据提出了计算中所需的方阱流体的径向分布函数的关联式。导热系数方程中的能量参数由物质的临界温度估算，而硬壳体积则由基团贡献法获得。考虑到实际液体有别于方阱流体，在实际液体导热系数计算时引入了一个与密度有关的校正参数。使用该导热系数计算方程，对液体氩及10种液态烃类物质的导热系数进行了计算，其计算的平均相对误差小于5.3%。在流体的扩散系数性质研究方面，利用普遍化的van der Waals方程中的自由体积，结合Cohen-Turnbull理论以及硬球流体的空穴函数，对纯流体以及二元混合物的扩散系数进行研究。计算中，纯物质的硬球直径σ和特征参数α根据各物质的自扩散系数的实验数据回归得到。计算结果表明本文的自由体积理论能够很好地关联纯液体地自扩散系数。另外我们还将本文的自由体积理论直接扩展应用于液体混合物的互扩散系数的预测，对大部分体系的预测偏差在10%以内。关键词：导热系数，方阱，径向分布函数，扩散系数，硬球，普遍化范德华方程

Thermal conductivity and diffusion coefficient for fluids and their mixtures are the basic properties in the industry and process design such as metallurgy, environment chemistry, biochemistry and nuclear engineering. The investigation on these transport properties provides a macroscopic physical understanding of the intermolecular potentials and microstructures. The thermal conductivity and diffusion coefficients for fluids and their mixtures are studied in this work, using the exist statistical mechanic theories, and this will provides basic data for the design of various industrial process involved.In present work, an equation based on the squared-well model is proposed to calculate thermal conductivities of liquids. The obtained equation includes two distinct parts, a translational and an internal part. For the convenience of calculation, empirical expressions of the radial distribution functions for the square-well fluid are obtained according to the molecular simulation data. The energy parameter in the equation for thermal conductivity is estimated from critical temperature of corresponding substance and the hard-core volume is obtained using a group contribution method. In the calculation of thermal conductivities of real liquids, a correction parameter dependent on density is introduced to consider the difference between the real fluid and the square-well model fluid. The thermal conductivities of liquid argon and ten hydrocarbons are calculated using the proposed equation and the average relative deviations are smaller than 5.3%.Investigation on the self-diffusion coefficients of liquids and mutual diffusion coefficients of liquid mixtures by combining the generic van der Waals equation of state and the Cohen-Turnbull free volume theory is also carried out. The state and the Cohen-Turnbull free volume theory is also carried out. The Cohen-Turnbull characteristic parameter α and hard-core σ are regressed from the experimental self-diffusion coefficient data by using the cavity function for hard sphere fluid. The calculated results show that the present free volume theory can be used to correlate the self-diffusion coefficients of liquids with high accuracies. In addition, the present free volume theory has been directly extended to predict the mutual diffusion coefficients for liquid mixtures. For most binary systems, the predicted deviations are within ±10%. Key words: thermal conductivity, squared-well model, radial distribution function, diffusion coefficient, hard sphere, generic van der Waals equation