ChE Seminar – Dr. Don Collins (Texas A&M University)
November 28 @ 3:30 pm - 4:30 pm
Host: Drs. Lea Hildebrandt Ruiz and David Allen
Director of the Center for Atmospheric Chemistry and the Environment
My research focuses on the properties and effects of atmospheric aerosols. On a regional to global scale, the efforts of our research group are concentrated on investigating radiative forcing by tropospheric aerosols, while on a local to regional scale, similar analytical tools are used to improve our understanding of air pollution. Most of our work is done in the field with instruments that we design and build.
Much of our recent and near-future research is centered on use of field-deployable environmental chambers in which gas phase composition and solar intensity mirror ambient conditions. These Captive Aerosol Growth and Evolution (CAGE) chambers are roughly 1 cubic meter all-Teflon cylindrical enclosures into which generated and size-classified particles are injected. Those captive particles are then repeatedly sampled over periods of several hours or even a day using various instruments. Recent experiments have included measurement of the structural and optical changes of soot particles, of the fluorescence characteristics and viability of biological particles, and of the nighttime production of secondary organic aerosol through nitrate radical reactions.