AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Chemical Analysis of Various Laboratory-Generated Particles by Using a Newly Developed Single Particle Mass Spectrometer
HEE-JOO CHO, Donggeun Lee, Kihong Park, Gwangju Institute of Science and Technology, Gwangju, Korea
Abstract Number: 261 Working Group: Instrumentation and Methods
Abstract Atmospheric aerosols are very important on atmospheric chemistry, global climate, air quality, and adverse health effects. Most of these atmospheric processes are closely related with individual particle size, chemical composition and mixing state. However, it is very challenging to determine single particle chemical composition in real time due to its small mass and complex mixing state. Single particle aerosol mass spectrometry (SPMS), which commonly uses laser for evaporation and ionization of individual particles, can be considered as a useful tool to determine chemical constituents of single particles in real time. It can detect not only non-refractory components, but also refractory constituents. In this study, a new SPMS was developed to analyze chemical composition and mixing state of single particles produced from various sources. The SPMS consist of two high vacuum chambers that are separated by a skimmer with 3 mm inner diameter, and each chamber is pumped down by two turbo molecular pumps. An orifice (with inner diameter of 100 micro-meter) and aerodynamic lens were newly designed to transport 90-1100 nm particles with high efficiency. The Nd:YAG laser with a 266 nm wavelength and a frequency of 20 Hz was used for particle ionization to achieve high hitting efficiency. Also, a triggering system by using a scattering laser was developed to detect particles at low concentration. Single particle mass spectra for particles from biomass burning, coal combustion, bubble bursting from seawater, and re-suspended particles from collected road dust were compared. Clustering of various types of particles is being performed.