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dc.contributor.advisorZhang, Renyien_US
dc.creatorZhao, Junen_US
dc.date.accessioned2010-01-15T00:11:07Zen_US
dc.date.accessioned2010-01-16T00:32:08Z
dc.date.available2010-01-15T00:11:07Zen_US
dc.date.available2010-01-16T00:32:08Z
dc.date.created2007-12en_US
dc.date.issued2009-05-15en_US
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-2424
dc.description.abstractAerosol particles have profound impacts on human health, atmospheric radiation, and cloud microphysics and these impacts are strongly dependent on particle sizes. However, formation and growth of atmospheric particles are currently not well understood. In this work, laboratory and theoretical studies have been performed to investigate the formation and growth of atmospheric particles. The first two parts of the dissertation are a laboratory investigation of new particle formation and growth, and a theoretical study of atmospheric molecular complexes and clusters. The nucleation rate was considerably enhanced in the presence of cis-pinonic acid and ammonia. The composition of the critical cluster was estimated from the dependence of the nucleation rate on the precursor concentration and the time evolution of the clusters was then simulated using molecular dynamic simulations. Results from quantum chemical calculations and quantum theory of atoms in molecules (QTAIM) reveal that formation of strong hydrogen bonding between an organic acid and sulfuric acid is likely responsible for a reduction of the nucleation barrier by modifying the hydrophobic properties of the organic acid and allowing further addition of hydrophilic species (e.g., H2SO4, H2O, and possibly NH3) to the hydrophilic side of the clusters. This promotes growth of the nascent cluster to overcome the nucleation barrier and thus enhances the nucleation in the atmosphere. The last part of this dissertation is the laboratory investigation of heterogeneous interactions of atmospheric carbonyls with sulfuric acid. Direct measurement has been performed to investigate the heterogeneous uptake of atmospheric carbonyls on sulfuric acid. Important parameters have been obtained from the time-dependent or timeindependent uptake profiles. The results indicated that the acid-catalyzed reactions of larger aldehydes (e.g. octanal and 2, 4-hexadienal) in sulfuric acid solution were attributed to aldol condensation in high acidity. However such reactions do not contribute much to secondary organic aerosol (SOA) formation due to the low acidity under tropospheric conditions. On the other hand, heterogeneous reactions of light dicarbonyl such as methylglyoxal likely contribute to SOA formation in slightly acidic media. The reactions of methylglyoxal in the atmospheric aerosol-phase involve hydration and subsequent polymerization, which are dependent on the hygroscopicity, rather than the acidity of the aerosols.en_US
dc.format.mediumelectronicen_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.subjectaerosolen_US
dc.subjectnucleationen_US
dc.subjectsulfuric aciden_US
dc.subjectorganic aciden_US
dc.titleExperimental and theoretical investigation of nucleation and growth of atmospheric aerosolsen_US
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentAtmospheric Sciencesen_US
thesis.degree.disciplineAtmospheric Sciencesen_US
thesis.degree.grantorTexas A&M Universityen_US
thesis.degree.nameDoctor of Philosophyen_US
thesis.degree.levelDoctoralen_US
dc.contributor.committeeMemberCollins, Don R.en_US
dc.contributor.committeeMemberDuce, Robert A.en_US
dc.contributor.committeeMemberMcGraw, Robert L.en_US
dc.contributor.committeeMemberNorth, Simon W.en_US
dc.type.genreElectronic Dissertationen_US
dc.type.materialtexten_US
dc.format.digitalOriginborn digitalen_US


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