Ozone is the most damaging component of smog and results in a variety of physiological effects that may significantly impact public health in polluted urban areas. The mechanism by which ozone is formed in photochemical smog involves an alkyl peroxy radical intermediate that couples the chemistry of NO to odd oxygen formation. The goal of this project is to measure the rate coefficients for reactions of alkyl peroxy radicals with a number of trace atmospheric constituents. The project has three distinct components. First, the mid-IR spectra of alkyl peroxy radicals will be determined using a long path length absorption FTIR apparatus. Alkyl peroxy radicals will be generated by reaction of atomic chlorine with the parent alkane followed by association with molecular oxygen. Second, the IR spectra will be verified using both experimental and theoretical techniques. Experimentally, disappearance of the observed bands will be monitored followed titration of the alkyl peroxy radical with an excess of either chlorine or nitric oxide. IF frequencies and intensities will also be determined using ab initio computations. The geometry and energetics of the radical will be calculated using 2nd order Moeller-Plesset perturbation theory with a 6-31G* basis set. Frequencies and intensities are calculated from the optimized geometry of the radical. Third, the rate coefficients will be measured for reactions of alkyl radical with nitric oxide (NO), nitrogen dioxide (NO2), ozone (O3), and sulfur dioxide (SO2). Kinetic measurements will be performed on a flash photolysis/pulsed CO2 laser thermal lens spectrometry apparatus in which peroxy radicals are generated by photolysis of a gas mixture including Cl2, the parent alkane, and oxygen, and the concentration of the peroxy radical is monitored using thermal lens spectroscopy. Kinetic information is acquired by varying the time delay between firing of the xeno flashlamp and Co2 laser. The rate coefficients determined in this study will ultimately be used in chemical models of urban air chemistry to determine the impact of individual hydrocarbon species on the production of ozone in smog.

Project Start
2000-07-01
Project End
2001-06-30
Budget Start
Budget End
Support Year
29
Fiscal Year
2000
Total Cost
$73,250
Indirect Cost
Name
California State University Los Angeles
Department
Type
DUNS #
City
Los Angeles
State
CA
Country
United States
Zip Code
90032
Durvasula, Ramani S (2017) Personality Disorders and Health: Lessons Learned and Future Directions. Behav Med 43:227-232
Crespo, Noe C; Yoo, Eun Jung; Hawkins, Steven A (2011) Anthropometric and lifestyle associations of bone mass in healthy pre-menopausal Mexican and Asian American women. J Immigr Minor Health 13:74-80
Kumar, Satish; Velasco, Kriya; McCurdy, Alison (2010) X-ray, kinetics and DFT studies of photochromic substituted benzothiazolinic spiropyrans. J Mol Struct 968:13-18
Pech, Herbe; Henry, Amanda; Khachikian, Crist S et al. (2009) Detection of geothermal phosphite using high-performance liquid chromatography. Environ Sci Technol 43:7671-5
Jiang, Dianlu; Dinh, Kim Lien; Ruthenburg, Travis C et al. (2009) A kinetic model for beta-amyloid adsorption at the air/solution interface and its implication to the beta-amyloid aggregation process. J Phys Chem B 113:3160-8
Hong, Hyun-Seok; Rana, Sandeep; Barrigan, Lydia et al. (2009) Inhibition of Alzheimer's amyloid toxicity with a tricyclic pyrone molecule in vitro and in vivo. J Neurochem 108:1097-1108
Jiang, Dianlu; Li, Xiangjun; Williams, Renee et al. (2009) Ternary complexes of iron, amyloid-beta, and nitrilotriacetic acid: binding affinities, redox properties, and relevance to iron-induced oxidative stress in Alzheimer's disease. Biochemistry 48:7939-47
Kumar, Satish; Chau, Cindy; Chau, Gordan et al. (2008) Synthesis and metal complexation properties of bisbenzospiropyran chelators in water. Tetrahedron 64:7097-7105
Kumar, Satish; Hernandez, David; Hoa, Brenda et al. (2008) Synthesis, photochromic properties, and light-controlled metal complexation of a naphthopyran derivative. Org Lett 10:3761-4
Valentine, Sonya C; Contreras, Deisy; Tan, Stephanie et al. (2008) Phenotypic and molecular characterization of Acinetobacter baumannii clinical isolates from nosocomial outbreaks in Los Angeles County, California. J Clin Microbiol 46:2499-507

Showing the most recent 10 out of 42 publications