Measuring Double Layer Forces Using Total Internal Reflection Microscopy

这项研究将使用一种名为全内反射显微镜(TIRM)的技术来测量胶体颗粒相对于平面的位置。TIRM是基于测量粒子在全反射表面的逝去波区散射的光的强度。由于光强随距离的强烈变化，使得纳米分辨率成为可能。通过测量处于平衡状态的系统的位置随时间的变化，人们能够推断粒子与表面之间的相互作用或力的势能作为分离的函数。将改进该技术，并将其用于推导双电层力。这项研究将为胶体科学提供一种新的、极其有用的工具。它将对胶体力的理论进行批判性的评价。这一结果对于理解颗粒沉积速率和沉积模式以及胶体力主导的绿色物体的固结将非常重要。

This research will employ a technique called total internal reflection microscopy (TIRM) for the measurement of colloidal particle position relative to a flat surface. TIRM is based on measuring the intensity of light scattered by a particle in the evanescent wave region of an otherwise totally reflecting surface. Due to the strong variation of intensity with distance, nanometer resolution is possible. By measuring the time variations of position for a system at equilibrium, one is able to infer the potential energy of interaction or force between the particle and surface as functions of the separation. The technique will be improved and used to deduce electrical double layer forces. The research should provide a new and extremely useful tool for colloid science. It will give a critical evaluation of the theories for colloidal forces. The results will be very important to understanding particle deposition rates and deposition patterns as well as consolidation of green bodies dominated by colloidal forces.