Renyi Zhang
Professor of Atmospheric Sciences and of Chemistry
Ph.D., Massachusetts Institute of Technology
Contact
Information:
Department of Chemistry
Texas A&M University
College Station, TX 77843-3255
Phone:
(979) 845-7656
Fax:
zhang@ariel.met.tamu.edu
Our research program covers several aspects in atmospheric chemistry:
(i) photochemical oxidation of hydrocarbons emitted from anthropogenic and biogenic sources has major implications for local and regional air quality. We conduct laboratory work to investigate the hydrocarbon oxidation reactions initiated by hydroxyl radical OH and other radical species, focussing on the formation of intermediate radicals and their subsequent degradation reactions. In addition, calculations using quantum chemical and kinetic rate theories are performed to study the structures, energetics, and isomeric branching to assess the preferred pathways of the organic radicals. Our objective is to quantitatively understand the kinetics and mechanism of atmospheric volatile organic compounds (VOCs) and their roles in tropospheric ozone and secondary aerosol formation.
OH-isoprene Reactions:
(ii) Aerosols in the atmosphere profoundly impact human health, atmospheric radiative transfer, and climate. We combine experimental and theoretical approaches to investigate nucleation, growth, and transformation of aerosols at the fundamental molecular level. These include elucidation of the formation of thermodynamically stable clusters from molecular complexes and clusters, the growth of stable clusters to nano- and submicrometer-sized particles, and transformation and properties of submicrometer-sized particles.
Atmospheric Soot Aging:
Aerosol nucleation and growth:
(iii) We develop state-of-the-art instrumentation to measure trace gaseous compounds and aerosols in the atmosphere. Our instruments have been deployed to study multi-phase atmospheric chemical processes in Houston and Mexico City.
Levitt, N. P.; Zhang, R.; Xue, H.; Chen, J. Heterogeneous chemistry of organic acids on soot surfaces, J. Phys. Chem. A 2007, 111, 4804-4814.
Zhang, R.; Suh, I.; Zhao, J.; Zhang, D.; Fortner, E.C.; Tie, X.; Molina, L.T.; Molina, M.J. Atmospheric new particle formation enhanced by organic acids, Science 2004, 304, 1487-1490.
Zhao, J.; Zhang, R.; Fortner, E.C.; North, S.W. Quantification of hydroxycarbonyls from OH-isoprene reactions, J. Am. Chem. Soc. 2004, 126, 2686-2687.
Fortner, E. C.; Zhao, J.; Zhang, R. Development of ion drift-chemical ionization mass spectrometry, Anal. Chem. 2004, 76, 5436-5440.
Suh, I.; Zhang, R.; Molina, L.T.; Molina, M.J. Oxidation mechanism of aromatic peroxy and bicyclic radicals from OH-toluene reactions, J. Am. Chem. Soc. 2003, 125, 12655-12665.
Zhang, D.; Zhang, R. Ozonolysis mechanisms of α- and β-pienes: Kinetics and mechanism, J. Chem. Phys. 2005, 122, 114308 (1-12).
Molina, M.J.; Zhang, R.; Wooldridge, P.J., Kim, J.E.; McMahon, J.R.; Chang, H.Y.; Beyer, K.D. Physical chemistry of the H2SO4/HNO3/H2O System: Implications for the formation of polar stratospheric clouds, Science 1993, 261, 1418-1423.
U.S. Patent Pending
Ion Drift - Chemical Ionization Mass Spectrometry (US Provisional Application # 60/598,188, Full Patent Application # 11/193,560)