报告题目：Mass Spectrometry of Atmospheric Aerosol: 1 nanometer to 1 micron

报告人： Douglas Worsnop, Aerodyne Research and University of Helsinki

报告地点：LAPC多功能厅

报告时间：2013年4月18日（周四）下午3：00

Abstract

Despite much effort in the past decade, uncertainties in both climate impacts and health effects of atmospheric aerosols remain large.  During the last ten years, aerosol mass spectrometry (AMS) has enabled size resolved measurement of sub-micron aerosol, showing that chemical composition is roughly 50:50 inorganic and organic worldwide.  Elemental analysis (C, H, O, N, S; via time-of-flight mass spectrometry, ToFMS) has separated primary and secondary aerosol organic and shown that organics become highly oxidized on a time scale of days, with low volatility oxidized organic dominating remote aerosol organic loading.  Recently soot particle aerosol mass spectrometer (SP-AMS), which uses an intracavity infrared laser for particle vaporization, has distinguished carbon cluster ion distributions from synthetic, diesel and biomass burning derived black carbon.  Size and chemically resolved organic and inorganic coatings of ambient BC have resolved emission and subsequent aging of urban BC containing particles.  Parallel application of ToFMS to directly sample the composition of atmospheric ions has provided the first observation of molecular cluster ions involved in atmospheric nucleation.  Chemical ionization mass spectrometry (CIMS), based on high pressure TOFMS, has extended detection to neutral molecules and clusters, detecting highly oxidized multifunctional organics (HOM) in the gas phase.  Ambient sampling and photochemical chamber experiments (Hyyti？l？, Finland, and Cosmics Leaving OUtdoor Droplets (CLOUD) at CERN, respectively) have resolved the interaction of H2SO4 and HOM vapors in nanoparticle particle nucleation and growth.