Office: Science I, ?
I am a firm believer that meaningful research experiences are an important aspect of undergraduate science education. Whenever possible, I provide research opportunities for interested students, and over the past four years, eleven undergraduate and high school students have carried out projects within the group. Several of these students have been co-authors of peer-reviewed journal articles, and have presented their work at professional meetings.
Field Studies of the Chemical Composition of Particulate Matter
High levels of particulate matter (PM) have been linked to adverse human health effects such as asthma and bronchitis. However, the origin of this link has not been established. Our work focuses on the possible role of quinones in inducing these health effects. It is well established that these chemicals can cause oxidative stress in biological systems that may result in cell damage. In this work, we are quantifying the mass loadings of quinones in PM samples collected within the San Joaquin valley. Preliminary data show that quinone levels are unusually high within the valley. We plan to investigate the possible correlation between quinone mass loadings and adverse health effects by comparing the levels of chemicals collected at various sites to the incidence of respiratory diseases among local residents.
Mechanistic Studies of Peroxy Radical Reactions
The reaction between organic peroxy radicals (RO 2 . ) and hydroperoxy radicals (HO 2 . ) is an important step in smog formation. Recently, we showed that these reactions are more complex than previously thought, and may result in the formation of multiple reaction products:
RO2. + HO 2. -> ROOH + O 2
We are conducting both experimental and theoretical studies to better establish the yields of these product sets. Determining the product yields from these reactions may improve our understanding of both smog formation and global warming.
Emissions Testing of ‘Environmentally-Friendly' Fuels
Biodiesel blends consist of mixtures of diesel fuel and vegetable oils such as canola. In addition to reducing our dependence on foreign oil, engines using biodiesel may also have cleaner emissions that may reduce ozone formation. Working with Dr. Gary Banuelos (USDA), we plan to test the emissions from biodiesels generated from crops grown within the San Joaquin valley to determine the possible environmental benefits of using these fuels.
Alam S. Hasson, Keith T. Kuwata, Manuel C. Arroyo a , and Erin B. Petersen “ Theoretical Studies of the Reaction of Hydroperoxy Radicals (HO 2 ) with Ethyl Peroxy (CH 3 CH 2 O 2 ), Acetyl Peroxy (CH 3 C(O)O 2 ), and Acetonyl Peroxy (CH 3 C(O)CH 2 O 2 ) Radicals ”, J. Photochem. Photobiol. A, 176, 218-230 (2005).
Myeong Y. Chung, Saddam Muthana, Rodhelen N. Paluyo, and Alam S. Hasson, “ Measurements of Effective Henry's Law Constants for Hydrogen Peroxide in Concentrated Salt Solutions ”, Atmos. Environ., 39, 2981-2989 (2005).
Keith T. Kuwata, Alam S. Hasson, Ray V. Dickinson, Erin B. Petersen, and Lukas K. Valin, “Quantum Chemical and Master Equation Simulations of the Oxidation and Isomerization of Vinoxy Radicals” , Journal of Physical Chemistry A, 109, 2514-2524 (2005).
Alam S. Hasson, Geoffrey S. Tyndall, and John J. Orlando, “ A Product Yield Study of the Reaction of HO 2 Radicals with Ethyl Peroxy (C 2 H 5 O 2 ), Acetyl Peroxy (CH 3 C(O)O 2 ), and Acetonyl Peroxy (CH 3 C(O)CH 2 O 2 ) Radicals” , J. Phys. Chem. A, 108 , 5979-5989 (2004).
Keith T. Kuwata, Kristen L. Templeton, and Alam S. Hasson, “Computational Studies of the Chemistry of Syn Acetaldehyde Oxide” , J. Phys. Chem. A, 107, 11525-11532 (2003).
Alam S. Hasson and Rhon E. Manor, “ Non-Steady State Behavior in Tropospheric Chemical Reactions ”, Atmos. Environ., 37 , 4735-3745, (2003).
Alam S. Hasson, Myeong Y. Chung, Keith T. Kuwata, Amber Converse, Debra Krohn and Suzanne E. Paulson, “The Reaction of Criegee Intermediates with Water Vapor – An Additional Source of OH Radicals in Alkene Ozonolysis?” , J. Phys. Chem. A, 107 , 6176-6182, (2003).
Alam S. Hasson and Suzanne E. Paulson, “ An Investigation of the Relationship between Gas-phase and Aerosol-borne Hydroperoxides in Urban Air ”, J. Aerosol Sci., 34 , 459-468 (2003) .