中文摘要：

利用Anton Paar DMA55精密数字密度计测定了288．15，298．15和308．15K甘氨酰甘氨酸在蔗糖-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Vφ和极限偏摩尔体积Vφ^0，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△trsVφ^0和理论水化数Nh．根据共球交盖模型，讨论了迁移偏摩尔体积和水化数的变化规律．结果表明，甘氨酰甘氨酸带电中心与蔗糖之间的结构相互作用对其迁移体积有正贡献，且占主导地位．甘氨酰甘氨酸的迁移偏摩尔体积为正值，且随着蔗糖浓度的增大而增大；理论水化数随温度升高、蔗糖浓度的增大而减小；温度升高，极限偏摩尔体积增大，迁移偏摩尔体积变化很小。

英文摘要：

Densities of glycylglycine in sucrose-water mixed solvent have been measured at 288.15, 298.15 and 308.15 K by Anton Paar DMA55 vibrating-tube digital densimeter. The apparent molar volume Vφ, limiting partial molar volume Vφ^0, partial molar volumes of transfer △trVφ^0 from water to sucrose-water mixed solvent and the hydration numbers Nh for glycylglycine have been calculated. The transfer volumes from water to sucrose-water mixed solvent and hydration numbers have been discussed in terms of the cosphere overlap model. The results show that a dominant structural interaction between the charged centers of glycylglycine and sucrose gives positive contribution to the transfer volume. The partial molar volumes of transfer of glycylglycine are positive, and increase with increasing sucrose concentration; while the hydration numbers decrease with increasing temperature and sucrose concentration. The limiting partial molar volume increases with increasing temperature, and partial molar volumes of transfer depend less on temperature.