[Single particle measurement of suspended soil dust using laser desorption/ionization time-of-flight mass spectrometry].
Real-time measurement of size and composition of single soil dust particles using an aerosol time-of-flight laser mas spectrometry (ATOFLMS) was designed in our lab. Each particle's aerodynamic diameter was determined by measuring the delay time between two continuous-wave lasers, a Nd:YAG laser with a 266 nm pulsed output was used to desorb and ionize aerosol particles, and ions formed in the laser desorption/ionization process were accelerated into the time-of-flight drift region where they separated by mass-to-charge ratio, then the composition of single particle was obtained. In the present paper, soil samples were collected from four different areas in China. After the pretreatment and suspension, the particle sample was then transferred to ATOFLMS through a plastic transfer line. During the campaign, a large number of size and mass spectra of single par ticles were obtained. The presence of crustal elements was observed in the mass spectra of individual particles. Iron, potassium aluminum and calcium constitute the two most commonly detected cations. Other common cations observed in the mass spectra o soil particles include magnesium, and sodium. The detection results exhibit that the coarse particles with size of 1-2 microm are dominate in the detected particles. Experimental results show the ATOFLMS have important practical value for researching and monitoring of atmospheric aerosol environment.
Guo
Xiao-yong
XY
Lab of Environmental Spectroscopy, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China. xyguo@aiofm.ac.cn
Zhao
Wen-wu
WW
Lin
Ying
Y
Gu
Xue-jun
XJ
Zheng
Hai-yang
HY
Fang
Li
L
Zhang
Wei-jun
WJ