胶体分形聚集体分维数与随时间变化的SERS强度关系研究

A Study of Relationship Between Time Dependent SERS Intensity and Fractional Dimension of Colloidal Fractional Aggregates

由于胶体聚集的动力学过程可用分形理论描述,从而对胶体动力学生长机制有了新的理解。Lin等研究了金胶、硅胶及聚乙烯乳胶的直接光散射后认为,胶体的两种生长机制DLCA和RLCA聚集体具有不依赖于胶体个性的普适分数维。对这一结果用不同方法对不同胶体进行验证十分必要。我们曾研究了吡啶吸附于AgBr胶体随时间变化的SERS规律。

The relations between time dependent SERS intensity and fractional dimension of colloidal fractional aggregates formed in both the diffusion and the reaction limited regimes were established in the paper. According to the relationship, the fractional dimensions of silver bromide colloid aggregates formed in the two regimes were given by the time dependent SERS intensity of adsorbed pyridine in AgBr sol, they are in good agreement with the universal value and suggest that SERS will be a useful tool in the study of kinetics of colloid aggregation, especially in the study of fractional structure of colloidal aggregates.