AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
The Roles of Gaseous Oxidation Products in Organic Nucleation from Ozonolysis of Atmospheric Terpenes
JUN ZHAO, Paul M Winkler, John Ortega, Peter McMurry, James N. Smith, National Center for Atmospheric Research
Abstract Number: 636 Working Group: Aerosol Nucleation: From Clusters to Nanoparticles
Abstract New particle formation due to ozonolysis of atmospheric terpenes may represent an important source of atmospheric particles, particularly in forested areas. In this work, we present chamber and flow tube measurements of gas-phase oxidation products from ozonolysis of monoterpenes (e.g., α-pinene) and sesquiterpenes (e.g., β-caryophyllene) with the Cluster Chemical Ionization Mass Spectrometry (the Cluster CIMS) using both positive and negative ion detection schemes. In either mode of operation, the oxidation product compounds/clusters were broken up by applying high collision energy in the conical octopole region and the pattern of the oxidation products was thus obtained. A series of high molecular weight oxidation products/clusters that likely contain carboxylic groups were observed from ozonolysis of both α-pinene and β-caryophyllene. Positive Matrix Factorization (PMF) was used to study the temporal evolution and category of the oxidation products that are related to particle production. The possible roles of those products/clusters in the formation of new particles in the chamber and flow tube experiments will be discussed.