HR: 1340h
AN: A13A-0881 [Abstracts]
TI: Experimental and Theoretical Investigation of Nucleation and Growth of Atmospheric Aerosols
AU: * Zhao, J
EM: jzhao@tamu.edu
AF: Department of Atmospheric Sciences, Texas A&M University, 3150 TAMU, College Station,
TX 77843-3150, United States
AU: Zhang, R
EM: Zhang@ariel.met.tamu.edu
AF: Department of Atmospheric Sciences, Texas A&M University, 3150 TAMU, College Station,
TX 77843-3150, United States
AU: Khalizov, A
EM: khalizov@neo.tamu.edu
AF: Department of Atmospheric Sciences, Texas A&M University, 3150 TAMU, College Station,
TX 77843-3150, United States
AU: Levitt, N P
EM: nicholas-paul-levitt@neo.tamu.edu
AF: Department of Atmospheric Sciences, Texas A&M University, 3150 TAMU, College Station,
TX 77843-3150, United States
AU: McGraw, R
EM: rlm@bnl.gov
AF: Atmospheric Sciences Division, Brookhaven National Laboratory, 2887 Bldg. 815E (75
Rutherford Dr.) PO Box 5000, Upton, NY 11973-5000, United States
AB:
Aerosol particles have profound impacts on human health, atmospheric radiation, and cloud microphysics and
these impacts are strongly dependent on the particle sizes. Currently, formation and growth of atmospheric
aerosol particles are not well understood. Our recent experimental study has shown that new particle formation in
the H2SO4–H2O system is considerably enhanced in the presence of sub-ppb level of aromatic acids (e.g.
benzoic acid, m-toluic acid, p-toluic acid), which represent the oxidation products of anthropogenic VOCs. In this
presentation, we present experimental study of ternary nucleation of sulfuric acid, water and cis-pinonic acid to
elucidate the role of biogenic organic acids in the new particle formation. In addition, we also discuss quantum
chemical calculations, quantum theory of atoms in molecules (QTAIM) and molecular dynamic simulations to
investigate the nature of the bonding interactions between the atmospheric nucleation precursors.
Recent environmental chamber studies have suggested that acid-catalyzed particle-phase reactions of organic
carbonyls lead to multifold increases in secondary organic aerosol (SOA) mass, contributing to the growth of the
atmospheric aerosol particles. We present experimental measurements of heterogeneous uptake of several
carbonyls on liquid H2SO4 in a wide range of acid concentrations and temperatures. The results indicate that the
uptakes of small carbonyls and large carbonyls on liquid sulfuric acid correspond to different mechanisms, which
may have important implication on the initial growth of newly nucleated nano-particles.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0320 Cloud physics and chemistry
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting