中文摘要：

五的系统Na+的溶解度，K+， Mg2+//Cl ?，没有? 3 -H2O 和它的二个第四级的分系统，Na+，K+， Mg2+//NO ? 3 -H2O 和K+， Mg2+//Cl ?，没有? 3 -H2O,被等温的方法在 25 点学习( C 和他们的阶段图被阴谋。在第四级的系统 Na+ 的平衡阶段图， K+ ， Mg2+//NO ? 在那里的 3 -H2O, 是一个不变的点，三条 univariant 曲线和有一盐的结晶化的三个区域：NaNO3， KNO3 和 Mg (NO3 ) 2

英文摘要：

The solubilities of the quinary system Na^＋ ,K^＋ ,Mg^2＋ //Cl ,NO 3 ^-H2O and its two quaternary subsystems, Na^＋ ,K^＋ ,Mg^2＋ //NO 3 -H2O and K^ ＋ ,Mg ^2＋ //Cl ,NO 3 ^-H2O,were studied by isothermal method at 25°C and their phase diagrams were plotted.In the equilibrium phase diagram of quaternary system Na^ ＋ ,K^ ＋ ,Mg ^2＋ //NO 3 ^-H2O, there are one invariant point,three univariant curves and three regions of crystallization with one salt：NaNO3, KNO3 and Mg（NO3）2·6H2O.In the equilibrium phase diagram of quaternary system K ^＋ ,Mg ^2＋ //Cl ,NO 3 ^-H2O,there are three invariant points,seven univariant curves and five regions of crystallization with one salt：KNO3,KCl, Mg（NO3）2·6H2O,MgCl2·6H2O and KCl·MgCl2·6H2O.In the equilibrium phase diagram of the quinary system Na ^＋ , K^ ＋ ,Mg ^2＋ //Cl ,NO 3^ -H2O,there are four invariant points,and seven regions of crystallization with one salt：NaCl, KCl,NaNO3,KCl·MgCl2·6H2O,KNO3,MgCl2·6H2O and Mg（NO3）2·6H2O.