PNNL 2014

Atmospheric chemical models generally underestimate the SOA burden. One reason may be that laboratory derived SOA yields from VOC oxidation represent a lower limit. We probed the photo-oxidation of isoprene at the Pacific Northwest National Laboratory (PNNL) Atmospheric Measurement Laboratory (AML) in collaboration with John Shilling. The chamber experiments were conducted in steady state mode to determine how SOA yields and the yields of their semi-volatile gaseous precursors change with varying levels of NOx. The HR-ToF-CIMS was instrumented with the FIGAERO inlet to measure the chemical composition in both the gas and particle phases.

Graduate student Emma D'Ambro installing the HR-ToF-CIMS instrument at the beginning of experiments at PNNL chamber...
Mid-experiment Indian dinne
Emma AFTER the completion of the experiments!