中文摘要：

用阿基米德法测定了NaCl-KCl-NaF-（SiO2）熔盐体系的密度，结果表明：体系的密度与温度呈良好的线性关系，且随温度的升高而降低；当NaCl含量不变时，用KCl逐步代替NaF时体系的密度逐渐减小；当KCl含量不变时，用NaCl逐步代替NaF时，体系的密度与NaCl含量呈倒抛物线关系；体系在XNaCl：XKCl=1：1时，随NaF含量的增加，体系密度逐渐增大。

英文摘要：

The density of KCl-NaCl-NaF-（SiO2） system was researched by Archimedes method. The results show that there is an liner relationship between density and temperature in the system. When the content of NaCl is constant, the density of the system decreases with substituting KCl for NaF little by little. When the content of KCl is constant, there is an inverse paracurve relation between the density and content of NaCl. When the ratio value of XNaCl to XKCl equal to 1, the density of the system increases with the increase of NaF content.