动态光散射技术测定土壤/粘土胶体的Hamaker常数  

Dynamic Light Scattering Technology Determination the Hamaker Constant of Soil/Clay colloids

作　　者：郭霞[1] 傅强[1] 田锐[1] 高晓丹[1] 朱华玲[1] 李航[1] 

机构地区：[1]西南大学资源环境学院/土壤多尺度界面过程与调控重庆市重点实验室,重庆400716

出　　处：《西南大学学报（自然科学版）》2016年第6期74-81,共8页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金项目(41371249);重庆市基础科学与前沿技术研究专项项目(cstc2014jcyjA00034);中央高校基本业务费专项基金项目(XDJK2015C174)

摘　　要：根据DLVO理论,带电胶体颗粒相互作用是范德华引力和静电斥力共同作用的结果.Hamaker常数是表征范德华引力的一个关键参数,因此获得胶体的Hamaker常数是定量表征颗粒相互作用力的一个重要基础.本研究提出了基于动态光散射技术测定土壤胶体Hamaker常数的新方法.并以蒙脱石、紫色土和黄壤胶体为实验材料,成功实现了其Hamaker常数的测定.测定结果表明:蒙脱石胶体的Hamaker常数A_(eff)=6.5×10^(-20)J,紫色土胶体的Hamaker常数A_(eff)=7.5×10^(-20) J,黄壤胶体的Hamaker常数A_(eff)=5.3×10^(-19) J.虽然理论上用动态光散射技术测定胶体的Hamaker常数应该具有一定优势.但是,由于目前没有测定Hamaker常数的标准方法,本法的精读验证难以实现.所以,采用动态光散射技术测定物质Hamaker常数,其可靠性还需要更多的研究进行确认.In the light of DLVO theory,the interaction of charged colloidal particles are the common result of the van der Waals interaction and electrostatic repulsion.The Hamaker constant is always an essential parameter involved.Therefore,determining the Hamaker constant of colloids is an important basis for quantitative characterization of the interaction force between colloidal particles.This study presents a new method to determine the Hamaker constant of soil colloids based on dynamic light scattering technology.We choose montmorillonite,purple soil and yellow soil colloids as experimental material.we achieved the determination of Hamaker constant successfully.The experimental results show that：the Hamaker constant was determined to be Aeff=6.5×10（-20） J for montmorillonite colloid,the Hamaker constant determined to be Aeff=7.5×10（-20） J purple soil colloid,the Hamaker constant determined to be Aeff=5.3×10（-19） J for yellow soil colloid.Although determining the Hamaker constant of colloid should have a certain advantage by dynamic light scattering technology theoretically.But,because now there is no standard method for determining of the Hamaker constant,the intensive verification of this method is difficult to achieve.Therefore,Determining the Hamaker constant of material by dynamic light scattering technology also need more research to confirm.

关 键 词：土壤胶体 Hamaker常数 范德华力 动态光散射 

分 类 号：S153.3[农业科学—土壤学]