摘要
利用电泳光散射法可以确定带电颗粒的电泳迁移率,由电泳迁移率计算颗粒的Zeta电位需要准确确定Henry函数的数值。为此,利用最小二乘算法对精确Henry函数值进行拟合,获得优化Henry函数表达式;基于Gouy-Chapman-Stern双电层模型理论,求解不同浓度、不同类型电解质溶液中颗粒的双电层厚度,从而获得准确的颗粒半径a与双电层厚度k-1的比值ka;最后利用优化的函数表达式获得准确的Henry函数值。使用该方法分别计算4种不同浓度电解质下颗粒的Zeta电位,实验结果表明,利用优化的Henry函数可以有效提高颗粒Zeta电位的计算精度,计算结果的相对误差小于1.0%。
The electrophoretic mobility of a charged particle can be determined using the electrophoretic light scattering method.To accurately determine the particles Zeta potential from the mobility requires the use of Henry function.An optimal expression for Henry function can be fitted by using the least squares algorithm.The thickness of the electric double layer in different concentrations and different types of electrolyte can be calculated using the Gouy-Chapman-Stern double layer model.An accurate value of kais obtained,here k-1 is the thickness of the double layer and ais the particle radius.The value of ka can be used in the optimal expression to determine an accurate value of Henry function.The particles Zeta potentials for four different concentrations are measured using this approach.The experimental results show that the optimal Henry function can be used to improve the calculation precision of particles Zeta potential,and the relative error of the calculation results is less than 1.0%.
引文
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