中文摘要：

利用精密数字密度计测定了298．15和308．15 K甘氨酰甘氨酸在KCl-水和NaCl-水混合溶剂中的密度，计算了甘氨酰甘氨酸的表观摩尔体积VФ和极限偏摩尔体积VФ^-，得到了其由纯水溶剂转移至混合溶剂中的迁移偏摩尔体积△trsVФ^-和理论水化数Nh.正的迁移偏摩尔体积说明在本文所研究的浓度范围内盐溶液可以提高球形蛋白的结构稳定性．结果表明，温度对迁移偏摩尔体积的影响很小；溶液中离子与甘氨酰甘氨酸带电中心间的相互作用占主导地位．利用共球交盖模型对结果进行了讨论．

英文摘要：

Apparent molar volumes VФ of glycylglycine in aqueous KCI and NaCl solutions have been obtained from densities at 298.15 and 308.15 K measured with a vibrating-tube densimeter. These data have been used to deduce partial molar volumes of transfer △trs VФ^- from water to different salt water mixtures. △trs VФ^- values are positive. This result arises from the interaction of KCI and NaCl with the charged centers of glycylglycine. The positive △trs VФ^- of glycylglycine shows that salts in the concentration range studied will stabilize the globular protein. The results show that △trs VФ^- depends less on temperature. The interaction between the charged centers of glycylglycine and ions dominates other forms interactions. The results have been explained using the cosphere overlap model.