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dc.contributor.authorZaveri, Rahul A.en
dc.date.accessioned2014-03-14T20:22:26Zen
dc.date.available2014-03-14T20:22:26Zen
dc.date.issued1997-06-27en
dc.identifier.otheretd-7197-18361en
dc.identifier.urihttp://hdl.handle.net/10919/30673en
dc.description.abstractAccurate simulations of the global radiative impact of anthropogenic emissions must employ a tropospheric chemistry model that predicts realistic distributions of aerosols of all types. The need for a such a comprehensive yet computationally efficient tropospheric chemistry model is addressed in this research via systematic development of the various sub-models/mechanisms representing the gas-, aerosol-, and cloud-phase chemistries. The gas-phase model encompasses three tropospheric chemical regimes - background and urban, continental rural, and remote marine. The background and urban gas-phase mechanism is based on the paradigm of the Carbon Bond approach, modified for global-scale applications. The rural gas-phase chemistry includes highly condensed isoprene and a-pinene reactions. The isoprene photooxidation scheme is adapted for the present model from an available mechanism in the literature, while an a-pinene photooxidation mechanism, capable of predicting secondary organic aerosol formation, is developed for the first time from the available kinetic and product formation data. The remote marine gas- phase chemistry includes a highly condensed dimethylsulfide (DMS) photooxidation mechanism, based on a comprehensive scheme available in the literature. The proposed DMS mechanism can successfully explain the observed latitudinal variation in the ratios of methanesulfonic acid to non-sea-salt sulfate concentrations. A highly efficient dynamic aerosol growth model is developed for condensing inorganic gases. Algorithms are presented for calculating equilibrium surface concentrations over dry and wet multicomponent aerosols containing sulfate, nitrate, chloride, ammonium, and sodium. This alternative model is capable of predictions as accurate for completely dissolved aerosols, and more accurate for completely dry aerosols than some of the similar models available in the literature. For cloud processes, gas to liquid mass-transfer limitations to aqueous-phase reactions within cloud droplets are examined for all absorbing species by using the two-film model coupled with a comprehensive gas and aqueous-phase reaction mechanisms. Results indicate appreciable limitations only for the OH, HO₂, and NO₃ radicals. Subsequently, an accurate highly condensed aqueous-phase mechanism is derived for global-scale applications.en
dc.publisherVirginia Techen
dc.relation.haspartzaveri.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectAir quality modelen
dc.subjectmonoterpenesen
dc.subjectdimethylsulfideen
dc.subjectaerosol chemistryen
dc.subjectaqueous chemistryen
dc.titleDevelopment and Evaluation of a Comprehensive Tropospheric Chemistry Model for Regional and Global Applicationsen
dc.typeDissertationen
dc.contributor.departmentChemical Engineeringen
dc.description.degreePh. D.en
thesis.degree.namePh. D.en
thesis.degree.leveldoctoralen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.disciplineChemical Engineeringen
dc.contributor.committeechairPeters, Leonard K.en
dc.contributor.committeememberSaylor, Rick D.en
dc.contributor.committeememberLittle, John C.en
dc.contributor.committeememberNeu, Wayne L.en
dc.contributor.committeememberConger, William L.en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-7197-18361/en
dc.date.sdate1997-06-27en
dc.date.rdate1997-08-05en
dc.date.adate1997-08-05en


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