The Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation supports the research of Professor Marcelo I. Guzman at the University of Kentucky to investigate important photoinduced and thermal aging processes of aqueous alpha-ketocarboxylic acids (alpha-KA, e.g., pyruvic, glyoxylic, and oxomalonic acids) as a mechanism of formation of Humic-like matter (HULIS). Cyclic thermal and photochemical processing will be used to mimic nighttime and daytime cycles of HULIS aging that will be monitored with different instruments in the presence of important electrolytes (e.g., Na+, HN4 +, Cl-, [SO4]2-) and surfactants. He will develop new fundamental understanding of chemical reaction mechanisms, as outline in a research plan based on direct, solid experimental evidence. The project will also study the production of reactive halogen species at the air-water interface. Solutions containing halides found in sea spray aerosol will be aerosolized and exposed to ozone gas to simulate the possible reactions of ozone destruction in the lower atmosphere.
The proposed research is undertaken because of the major role that marine aerosol plays in climate, visibility and air quality, and it is essential to understand the chemical reactions occurring in these airborne particles. This project will advance the scientific community's understanding of the mechanisms that deplete atmospheric ozone, and produce HULIS with implications to air quality, climate, and health. The principal investigator will develop the first atmospheric chemistry research and education program in the state and involve underrepresented graduate, undergraduate, and K-12 students. Graduate students will gain interdisciplinary knowledge and skills, and disseminate findings at scientific conferences and in peer-reviewed publications. Professor Guzman will continue his current research and mentoring relationships with the local Lafayette High School Pre-Engineering Program. The outreach activities are specifically oriented to training underrepresented graduate students, and mentoring minority undergraduates pursuing careers in science. Finally, through collaboration with the Appalachian Center at the University of Kentucky, the researcher will participate in educational forums requested by the public that will be videotaped and made available on the Internet.