甘氨酸在麦芽糖水和乳糖水溶剂中的体积性质

利用精密数字密度计在等电点下测定了甘氨酸分别在不同组成的麦芽糖-水和乳糖-水混合溶剂中的密度．计算了甘氨酸的表观摩尔体积、极限摩尔体积和理论水化数．根据结构水合作用模型讨论了迁移偏摩尔体积的变化规律，并与葡萄糖-纯水和蔗糖-纯水体系做了比较．结果表明，在等电点时甘氨酸分子在糖-水混合溶剂中体积效应的大小与三者的相对比例紧密相关，但最重要影响因素是等电点下的疏水相互作用。

Volumetric Properties of Glycine in Maltose-Water and Lactose-Water Mixed Solvents at 298.15 K

The densities of glycine in maltose-water and lactose-water mixed solvents were determined on isometric point at 298. 15 K. The apparent molar volumes,limiting partial molar volumes and hydration numbers of glycine were calculated. The transfer volumes from water to sugar-water mixtures were obtained and discussed in terms of the structural hydration interaction model. The results obtained were compared with that in glucose pure water and sucrose-pure water mixtures. It is concluded that the magnitude of enhancement effect on volume was related to molar ration among the glycine sugar and water, and was controlled by the stronger hydrophobic interaction between hydrophobic groups on isoelectric point.