CAREER: Vehicle-derived Ultrafine Particles and Their Adsorbates: Formation and Aging Effects on Organic Composition and Size Distribution

University Of Connecticut, Storrs CT

Investigators

Abstract

0132759 Holmen Very little is known about the organic chemical composition of the ultrafine particles emitted by vehicles and about the atmospheric processing of these particles as they age during transport in the atmosphere. This is especially true for the more polar organic compounds that have been linked to stronger mutagenic effects. The composition of these ultrafine particles, and the organic species adsorbed to the particles, has very important implications for particle reactivity and the resulting endpoint effects on environmental and human health. The Research Component focus is the processes that control the physical and chemical attributes of vehicle-derived ultrafine particles. The Research Component will: (1) design and build a new sampler for size- and time-resolved collection of ultrafine particles from vehicles; (2) conduct "aging" experiments on vehicle-derived ultrafine particles to determine reaction products during exposure to UV light, ozone, and NOx under controlled laboratory conditions; and (3) develop new analytical techniques to analyze the composition of both fresh and aged ultrafine particles. This research will help close the gap in understanding the mechanism of diesel soot toxicity and identify the conditions under which aging mechanisms produce significant polar organic species. The results of this research will allow the most complete model yet of the processes governing the formation of vehicle-derived PM polar organic species in the atmosphere.