一种纳米颗粒粒度分布的非接触测量方法

研究了基于高频宽带超声衰减谱非接触式方法测量纳米颗粒悬浊液中颗粒相粒度分布问题. 通过理论分析和数值计算，选择ECAH模型作为反演计算的理论模型. 以1%(j)的纳米银水悬浊液作为实验样品，采用标称中心频率为50 MHz的超声换能器和变声程脉冲回波法进行了非接触测量，获得了可利用的高频宽带(10~50 MHz)超声衰减谱，结合理论模型和最优正则化算法反演出纳米颗粒的粒度分布. 实验结果与透射电子显微镜法和高速离心沉降法的测定结果吻合较好，表明该方法可测量悬浊液中纳米颗粒粒度分布.

An Investigation on Measurement of Nanoparticle Size Distribution Using Non-invasive Method

A non-invasive method with high and broad frequencies acoustic attenuation spectra to measure nano-particle size distribution in solid-liquid two-phase system was investigated. Through theoretical analysis and numerical calculation, ECAH (Epstein-Carharts- Allegra-Hawley) model was presented for the theoretical model of inversion calculation. Nano-silver particle suspensions with volume fraction of 1% were used for experimental samples. Using an ultrasonic transducer with center frequency of 50 MHz, the variable path-length and pulse-echo methods were employed to carry out experimental measurements, in which sound attenuation spectra of high and wide frequencies (10~50 MHz) were obtained, and combined with theoretical model and optimal regularization technique to inverse nano-particle size distribution. Experimental results compared with those from the transmission electron microscopy method and the high-speed centrifugal sedimentation method demonstrated that the method could be used for measurement of nano-particle size distribution in solid-liquid two-phase system.