The physicochemical properties of the (LiF (1) + MgF₂ (2))_eut + LaF₃ (3) molten system have been investigated. The phase equilibria, density and volume properties, electrical conductivity, and surface tension have been selected for investigation. The phase equilibria have been measured by thermal analysis method, and the CALPHAD method for optimizing of the phase diagram has been used in order to interpret the obtained experimental data. Calculated values of the eutectic point of the binary system (LiF (1) + MgF₂ (2))_eut have the following coordinates: eutectic temperature T_eut = 998 K and x₂ = 0.3095 and calculated composition of the ternary eutectic, according to the thermodynamic model, are at x₁ = 0.6627, x₂ = 0.2718, and x₃ = 0.0655. The Archimedean method of hydrostatic weighing was used for density measurements, a method based on the principle of phase shift measurement was used for electrical conductivity measurements, and the maximum bubble pressure method was used for surface tension measurements. The calculated concentration dependencies of particular physicochemical properties showed increasing character for density, partial molar volume, and electrical conductivity, while decreasing character was observed for surface tension. These data have been compared with corresponding physicochemical properties of two other molten systems: (LiF + CaF₂)_eut + LaF₃ and (LiF + NaF)_eut + LaF₃.

中文翻译：

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三元（LiF + MgF ₂）_eut + LaF ₃熔体体系的理化研究

研究了（LiF（1）+ MgF ₂（2））_eut + LaF ₃（3）熔融体系的物理化学性质。选择了相平衡，密度和体积特性，电导率和表面张力进行研究。通过热分析方法测量了相平衡，并使用了用于优化相图的CALPHAD方法来解释获得的实验数据。二元体系的共晶点（LiF（1）+ MgF ₂（2））_eut的计算值具有以下坐标：共晶温度T _eut = 998 K和x ₂= 0.3095，根据热力学模型，计算出的三元共晶组成为x ₁ = 0.6627，x ₂ = 0.2718和x ₃= 0.0655。静压称重的阿基米德方法用于密度测量，电导率测量使用基于相移原理的方法，表面张力测量使用最大气泡压力法。计算出的特定物理化学性质的浓度依赖性显示出密度，部分摩尔体积和电导率的增加特性，而表面张力观察到减小的特性。这些数据已与其他两个熔融系统的相应理化性质进行了比较：（LiF + CaF ₂）_eut + LaF ₃和（LiF + NaF）_eut + LaF ₃。