Design of a Small, Battery-Operated Nanoparticle Sizer

摘要

A small, portable nanoparticle sizer has been developed to provide an affordable method to measure nanoparticle size distributions. The new nanoparticle sizer incorporates a SMPS Spectrometer into a chassis that is <1 cu.ft. The instrument consists of: 1) an inlet cyclone to remove large particles, 2) a cross-flow uni-polar charger to increase nanoparticle transmission efficiency and eliminate logistical issues with radioactive neutralizers, 3) a Radial DMA which is lightweight and compact, 4) an isopropyl based Condensation Particle Counter (CPC) to provide accurate measurements at high and low concentrations using a working fluid acceptable in workplace environments, and 5) the instrument control, analysis and data logging can be done through the instrument touch screen. In addition to nanoparticle size distributions, the instrument can be used to collect second by second concentration data at a single nanoparticle size. If the nanoparticle source of concern generates 50nm particles, the particle concentration at 50nm can be monitored with 1 second time resolution. Instrument design will be reviewed and performance data including counting efficiency, size resolution and concentration range will be discussed.