Light Scattering Method for Aerosol Sizing Based on Machine Learning

Abstract

Optical scattering has been widely used for aerosol sizing due to its noninvasive and real-time measurement. However, it is crucial to retrieve the particle size distribution (PSD) of aerosols without prior knowledge of the refractive index. Now, it has been a great challenge to measure the refractive index in situ. In this study, a novel PSD sensing method utilizing the light scattering angular spectrum (LSAS) and machine learning techniques is proposed to address this challenge. The complex nonlinear relationship between LSAS and PSD can be constructed while accounting for the refractive index of aerosols. A miniaturized prototype sensor is designed and tested on different sizes of aerosol samples. The experiment results showed that the maximum Kullback−Leibler divergence (D KL ) of PSD is 0.07, which indicates that the sensing method can provide the ability for highly accurate aerosol PSD measurement without requiring prior knowledge of the refractive index. The compacted prototype sensor shows great potential for aerosol analysis in conventional field measurements outside the laboratory.

Preparation of Ni Nanowires Covalent Organic Framework Composites with High Electrochemical Stability and Supercapacitor Performance

“…As one of the energy storage devices, supercapacitors have received widespread attention due to their high power density, long cycle life, excellent charging and discharging performance, safety and reliability . These functions of supercapacitors are influenced mainly by their electrodes, which can be divided into electrochemical (EC) double-layer and pseudocapacitance behaviors. Typically, electrode materials are divided into four main categories: carbon-based electrode materials, , transition metal oxide materials, , conductive polymers, , and composites. , Covalent organic frameworks (COFs) are porous crystalline materials connected by covalent bonds with high specific surface area, open channels and active sites, stable backbone structure, and highly ordered periodic structure, which have a wide range of applications in many fields.…”