中文摘要：

采用等温溶解平衡法研究了五元体系Na^＋，K^＋，Mg^2＋／／Cl^-，NO3^--H2O在298．16K、氯化钠饱和时各盐的溶解度和饱和溶液的物化性质（密度，电导率）以及四元体系Na^＋，Mg^2＋／／Cl^-，NO3^-- H2O的相平衡关系．研究表明：在298．16K，氯化钠饱和时该五元体系溶解度相图由六个结晶区、九条单变量溶解度曲线和四个零变量点构成，六个结晶区分别对应于NaNO3＋NaCl，KNO3＋NaCl，KCl＋NaCl，Mg（NO3）2·6H2O＋NaCl，MgCl2·6H2O＋NaCl和复盐KCl·MgCl2·6H2O＋NaCl：在298．16K时，该四元体系的相图由四个结晶区、五条单变量溶解度曲线和二个零变量点构成，四个结晶区分别对应于NaNO3，NaCl，Mg（NO3）2·6H2O，MgCl2·6H2O．

英文摘要：

Solubilities of each salt in the system Na^＋, K^＋, Mg^2＋//Cl^-, NO3 -H2O saturated with NaCl and the system Na^＋, Mg^2＋//Cl^-, NO3 ^--H2O were investigated by isothermal method at 298.16 K. The physico-chemical properties, such as densities and conductivities, of the corresponding solutions were determined too. The dry salt phase diagram of the system Na^＋, K^＋, Mg^2＋//Cl^-, NO3 ^--H2O saturated with NaCl consists of six crystallization regions （NaNO3＋NaCl, KNO3＋NaCl, KCl＋NaCl, Mg（NO3）2·6H2O＋ NaCl, MgCl2·6H2O＋NaCl and KCl·MgCl2·6H2O＋NaCl）, nine univariant curves and four invariant points. The dry salt phase diagram of the system Na^＋, Mg^2＋//Cl^-, NO3 -H2O consists of four crystallization regions （NaNO3, Mg（NO3）2·6H2O, MgCl2·6H2O and NaCl）, five univariant curves and two invariant points.