No abstract

This paper is an attempt to extract useful thermodynamic information from the experimental activity of zinc in Zn-Bi binary liquid alloy at different temperatures. The molecular interaction volume model (MIVM) was adopted to calculate a number of temperature dependent thermodynamic functions, including activity, free energy of mixing, concentration fluctuations in the long-wavelength limits, and diffusion. The reasonable agreement of the modeled thermodynamic parameters with the existing experimental data verified that the MIVM is quite convenient and reliable in the assessment of the thermodynamic properties of binary liquid alloys. K e y w o r d s : Zn-Bi, thermodynamic properties, molecular interaction volume model

Quoted measurements of viscosity and our results of electrical resistivity experiments indicate two anomalous changes of physical properties take place in molten eutectic Cu37Sb63. Effective pair inter-ionic potentials evaluated using the hyper-netted chain theory further confirms the presence of two discontinuous structural transitions within the ranges from 1273K to 1073K and from 1073K to 903K, respectively. Moreover, the result of electrical resistivity experiments suggests the two structural transitions for molten Cu37Sb63 are reversible.

The thermodynamic properties of fission products in molten salt and liquid metal have a great influence on the disposal of nuclear waste in the nuclear fuel cycle industrial system. This paper attempts to extract useful thermodynamic information from the only few experimental activities of lanthanides (Ce, Pr, La) in liquid Bi at different temperatures. The molecular interaction volume model (MIVM) was adopted to model and predict some temperature-dependent thermodynamic functions, including activity, infinite dilute activity coefficient, and molar excess Gibbs energy. The minor average of Δ G ¯ error indicated that assuming εji − εii is a constant is reasonable. On this basis, the natural logarithm of the interaction coefficients and the natural logarithm of the infinite dilute activity coefficient of lanthanides (Ce, Pr, La) in the Bi-based metal melt, these two parameters, show the linear relationship with the reciprocal of temperature. The reasonable agreement of the modeled thermodynamic parameters with the existing experimental data verified that the MIVM is quite convenient and reliable, which can provide guidance for separating fission products from molten salt reactors.

The self-association model is an effective theoretical method for determining the thermodynamic parameters of immiscible molten binary alloys. However, two important parameters (the ratios of numbers of two atoms in the cluster n and the interchange energy W) in the model had confusing temperature dependences, which prevented the statistical mechanical model from accurately predicting the physical and chemical properties at various temperatures. The ratios of the two atoms in the cluster and the interchange energy were proposed in this study to be linear with temperature, respectively, to analyze the segregation of liquid Zn–Bi alloys. The hypothesis about two key parameters is helpful to predict the segregating nature of liquid Zn–Bi alloys, as evidenced by the good accordance of the predicted thermophysical properties (activity, free energy of mixing, miscibility gap, entropy of mixing, partial molar entropy, and concentration fluctuation) with the existing experimental data.