双分散纳米颗粒系不同光强贡献比例下的动态光散射特性研究  

Study on the Characteristics of Dynamic Light Scattering for Dual Disperse Nano-Particles Based on Different Light-Intensity Contribution Ratio

作　　者：李誉昌 吴晓斌[1] 朱苏皖 邱健[1] 骆开庆[1] 韩鹏[1] 

机构地区：[1]华南师范大学物理与电信工程学院,广州510006

出　　处：《华南师范大学学报（自然科学版）》2015年第3期24-28,共5页Journal of South China Normal University(Natural Science Edition)

基　　金：国家自然科学基金项目(61371176);广东省自然科学基金项目(S2013010013699)

摘　　要：系统研究了103 nm/225 nm、103 nm/388 nm两种双分散颗粒系在不同光强贡献比例下的动态光散射特性,包括平均粒径、分散度poly、自相关函数及其斜率变化与光强贡献的关系.发现双指数法和最小二乘法反演平均粒径比较接近理论值,累积量法反演的平均粒径整体偏小;在大颗粒光强贡献较大时,poly的变化受小颗粒光强的影响较大,反之当小颗粒的光强贡献较大时,poly的变化受大颗粒光强的影响相对较小;在本文研究的条件下,光强贡献比和自相关函数斜率最小值对应的延迟时间具有较好的线性关系;指出在光强贡献比改变时,poly与自相关函数曲线斜率的最小值有相同的变化趋势.研究结果对双分散颗粒系动态光散射特性的精确测量及测量系统的优化有参考价值.Dynamic light scattering （DLS） for measuring the polydispersion nano-particles has become a hot area of research in recent years. The paper has investigated experimentally the characteristics of dynamic light scattering for dual disperse nano-partlcles of 103 nm/225 nm, 103 nm/388 nm under different light-intensity contribution ratio. The characteristics of the effective diameter, polydispersity （poly）, the autocorrelation function （ACF） and its first derivative have been analyzed systematically. It is found that the effective diameters inversed by the cumulant method tend to be smaller than those inversed by double exponential method and NNLS method. The plot of poly versus ratio is asymmetric, showing a fast increase when the ratio is low, i. e. , the large nano-particles contribute more light-intensity, whereas a slow decline when the ratio is high, that is, the small nano-particles contribute more. The delay time corresponding to the minimum value of the ACF slope has a good linear relationship to the light-intensity contribution ratio. The poly and the minimum value have the similar trend with the light-intensity contribu- tion ratio. These results can improve the date processing and the system promising of the DLS technique for measuring the polydispersion particles.

关 键 词：动态光散射 双分散纳米颗粒 平均粒径 分散度 自相关函数曲线 

分 类 号：O436.2[机械工程—光学工程]