Chemical Composition of Newly-Formed Organic Aerosols by Spot-Sampler nano-DESI
EMSL Project ID
49231
Abstract
One of the important challenges in elucidating the role of atmospheric particles in global climate is to identify the chemical pathways by which nanometer-sized particles grow to sufficient size to become cloud condensation nuclei. Although too small when first formed to directly affect climate, their number concentrations and observed growth rates are large, and significant numbers may reach the sufficient size to serve as cloud condensation nuclei, and thereby influence the physical characteristics and lifetime of clouds. Of specific interest is the role played in the growth of these newly formed particles by amines, and sulfonated organic compounds and other organic species. Proposed is detailed, off-line characterization of ambient nanoparticle aerosol samples using the nano-Desorption Electrospray Ionization Mass Spectrometery (nano-DESI-MS) at Environmental Molecular Sciences Laboratory (EMSL). Samples will be collected with an aerosol concentrator – collector (the Spot Sampler) which provides highly focused deposits tailored to the nano-DESI-MS analysis. With its high-resolution mass spectrometer, the EMSL nano-DESI-MS provides the molecular formula of individual compounds, thereby readily identifying presence of amines, nitrated and sulfonated organics, as well as oxygen to carbon ratios. The data will be used in conjunction with other measurements at the site to elucidate pathways by which newly formed particles grow, and to characterize differences between nucleation and non-nucleation periods.Size-selected samples of atmospheric nanoparticles
Project Details
Project type
FICUS ARM Research
Start Date
2016-05-11
End Date
2017-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)