Activity and activity coefficient of water in aqueous solutions and their relationships with solution structure parameters
Activity and activity coefficient of water in aqueous solutions and their relationships with solution structure parameters
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DOI：
10.1271/bbb.61.466
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发表时间：
1997-03-01
影响因子：
1.6
通讯作者：
Nakamura, K
中科院分区：
文献类型：
--
作者：
Miyawaki, O;Saito, A;Nakamura, K
用Hildebrand和Scott方程计算了不同电解质、糖、醇、酰胺和尿素溶液的凝固点降低值，并计算了水活度和水活度系数γ（W）。由凝固点降低值测得的水活度与室温下的水活度非常接近，表明温度对水活度的影响是明显的。水的活度系数可以用下面的公式很好地描述为溶质摩尔分数（X（S））的函数：γ（W）=exp（α X（S）（2）+ β X（S）（3））该方程中的参数α与单价电解质的B-粘度系数以及非电解质的水合参数相关性良好，并且糖的赤道-OH基团的数量表明溶液结构反映在该参数中。
The water activity and the activity coefficient of water (gamma(W)) were calculated from the freezing point depression by using the Hildebrand and Scott's equation for various solutions of electrolytes, sugars, alcohols, amide, and urea, The water activity measured from the freezing point depression was very close to that at room temperature, showing that the effect of temperature on the water activity is neglegible. The activity coefficient of water was described well as a function of the solute mole fraction (X(S)) by the following equation.gamma(W)=exp(alpha X(S)(2)+beta X(S)(3))The parameter alpha in this equation correlated well with the B-coefficient of viscosity for single-valent electrolytes, with the hydration parameter for nonelectrolytes, and with the number of equatorial-OH groups for sugars suggesting that the solution structure was reflected in this parameter.