动态光散射颗粒测量中相关函数最优截断点的确定  

Determination of Optimal Autocorrelation Function Truncation Point for Particle Size Measurement with Dynamic Light Scattering

作　　者：齐甜甜 刘伟[1] THOMAS J C 贾宏燕[1] 魏芹芹[1] 王雅静[1] 申晋[1] QI Tiantian;LIU Wei;THOMAS J C;JIA Hongyan;WEI Qinqin;WANG Yajing;SHEN Jin(School of Electrical and Electronic Engineering,Shandong University of Technology,Zibo,Shandong 255049,China;Group Scientific Pty Ltd.,Grange,South Australia 5022,Australia)

机构地区：[1]山东理工大学电气与电子工程学院,山东淄博255049 [2]科学集团有限公司,澳大利亚南澳大利亚州葛兰许5022

出　　处：《光子学报》2022年第3期357-366,共10页Acta Photonica Sinica

基　　金：Key Research and Development Project of Guangdong Province(No.2020B0101320002);Natural Science Foundation of Shandong Province(No.ZR2020MF124);Key Research and Development Program of Shandong Province(No.2019GGX104017)。

摘　　要：从动态光散射信号中反演纳米颗粒粒度分布,结果准确性和重复性受测量的自相关函数数据点影响,数据点长度不同会导致不同的反演结果。为了解决该问题,提出了一种根据拟合自相关函数的均方根误差来截断自相函数的方法,该方法通过设置拟合误差阈值来自适应地选择最佳自相关函数数据点数。实验结果表明,使用均方根误差阈值方法获得的颗粒粒度分布比其他方法获得的结果具有更高的准确性和更好的重复性。Dynamic light scattering technology is a common measurement method that can calculate the particle size distribution of nanoparticles at present.The particle size distribution obtained by the inversion of the autocorrelation function belongs to the problem of solving the first type of Fredholm integral equation,which is a typical ill-posed problem.The data near the baseline of the autocorrelation function has a lot of noise.Therefore,the accuracy and repeatability of the inversion results are affected by the data points of the autocorrelation function,and different data points of the autocorrelation function may lead to different inversion results.To overcome the shortcomings,the characteristics of the root-mean-square error of the fitted correlation function with the number of autocorrelation function points are investigated.The root-mean-square error curve as a function of number of autocorrelation function points can be divided into two stages:in the first stage,the root-mean-square error value of the fitted correlation function grows smoothly with the increase of the number of autocorrelation function points,and in the second stage,as the number of correlation function points increases,the root-mean-square error value of the fitted correlation function grows rapidly.The rapid growth of the root-mean-square error indicates that the noise contained in the autocorrelation function data increases and the reliability of the correlation function data decreases with increasing number of data points.The point of inflection of the root-mean-square error curve marks where the noise contribution from subsequent data points significantly increases the fitting error and produces poorer inversion results.With this in mind,root-mean-square error threshold method as the criterion to truncate the autocorrelation function be proposed.This method adaptively selects the optimal number of autocorrelation function data points by setting the root-mean-square error threshold.It can truncate the autocorrelation function according to

关 键 词：动态光散射 光子相关光谱 最佳数据点 自相关函数 均方根误差 颗粒粒度分布 纳米颗粒测量 

分 类 号：O439[机械工程—光学工程]