Comparisons of Physical Properties and Compositions of Irradiated Carbonyl-containing Aqueous Aerosols and Aerosol Mimic Solutions
JOSEPH WOO, Katherine Pierre-Louis, Bruno Loyola San Martin, Erin O'Leary, Daphna Fertil,
Lafayette College Abstract Number: 523
Working Group: Aerosol Chemistry
AbstractCarbonyl-containing volatile organic compounds (CVOCs) are ubiquitous in aqueous atmospheric aerosols, and have been identified as a source of a wide range of oligomeric products when aged under dark (nighttime) conditions. Recent studies exploring UV-irradiated (daytime) chemistry of dark-aged CVOC aqueous aerosol mimics have yielded further insight into their chemical fates, observing shifts in the extent of oligomerization in CVOC-derived heterocycles. The sustained gas-aerosol interface of droplets is hypothesized to enhance the formation of higher-mass and potentially surface-active products. This study explores the relative effect of surface/volume ratio on CVOC photochemistry by comparing the properties and extents of oligomerization of irradiated bulk, µL-scale hanging-droplet, and aerosolized CVOC/ammonium-sulfate solutions. ESI-MS, ex-situ surface tension, and UV/visible spectrophotometry measurements are reported.