A field-deployable instrument has been developed that isolates from an ambient aerosol population only those particles that have critical supersaturations, Sc, within a narrow, user-specified, range. This Differential Critical Supersaturation Separator (DScS) is designed to supply one or more particle size and/or composition analyzers to permit the direct examination of the factors that influence the activation properties of ambient aerosols. The DScS consists of two coupled parallel plate continuous flow thermal gradient diffusion cloud chambers housed within a single enclosure. Descriptions of instrument operation, construction and calibration data collected, when pure ammonium sulfate aerosols were injected into the DScS for operation at 0.15%< Sc<0.175%, 0.30%< Sc<0.35%, and 0.60% < Sc<0.70%, are included. Following instrument development, the DScS was deployed during March 2006 for the Megacities Impact on Regional And Global Environment (MIRAGE) field campaign in Mexico City, Mexico. Throughout the MIRAGE field campaign a Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) system measured aerosol size distributions and size-resolved hygroscopicity of DScS separated aerosol. The dry diameter (Dp*) of particles sampled in the TDMA system as well as the known Sc prescribed in the DScS were combined in a modified version of Köhler Theory to make predictions of particle hygroscopicity. These predictions frequently overestimated the measurements. Further analysis of DScS separated aerosols compares the known particle Sc to a predicted particle Sc, providing insight into particle activation efficiency. Overall, the sampled aerosol exhibited properties that indicate they were more efficient at activation than Köhler Theory would predict.

A field-deployable instrument has been developed that isolates from an ambient aerosol population only those particles that have critical supersaturations, Sc, within a narrow, user-specified, range. This Differential Critical Supersaturation Separator (DScS) is designed to supply one or more particle size and/or composition analyzers to permit the direct examination of the factors that influence the activation properties of ambient aerosols. The DScS consists of two coupled parallel plate continuous flow thermal gradient diffusion cloud chambers housed within a single enclosure. Descriptions of instrument operation, construction and calibration data collected, when pure ammonium sulfate aerosols were injected into the DScS for operation at 0.15%< Sc<0.175%, 0.30%< Sc<0.35%, and 0.60% < Sc<0.70%, are included. Following instrument development, the DScS was deployed during March 2006 for the Megacities Impact on Regional And Global Environment (MIRAGE) field campaign in Mexico City, Mexico. Throughout the MIRAGE field campaign a Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) system measured aerosol size distributions and size-resolved hygroscopicity of DScS separated aerosol. The dry diameter (Dp*) of particles sampled in the TDMA system as well as the known Sc prescribed in the DScS were combined in a modified version of Köhler Theory to make predictions of particle hygroscopicity. These predictions frequently overestimated the measurements. Further analysis of DScS separated aerosols compares the known particle Sc to a predicted particle Sc, providing insight into particle activation efficiency. Overall, the sampled aerosol exhibited properties that indicate they were more efficient at activation than Köhler Theory would predict.

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A series of ferrocenylimine [(£b5-C5H5)Fe(£b5-C5H4-C(Me)=N-R)]¡AR= nhexyl(1a)¡Acyclohexyl(1b)¡Aphenyl(1c)¡AN,N-dimethylethylamino(1d) ¡A4-methoxyphenyl(1e)¡A4-nitrophenyl(1f)¡Aand 2-methoxyethyl(1g)¡Ahave been synthesized by reaction of acetylferrocene and the corresponding amines through condensation reaction. Also 1,1¡¦-ferrocenyldiimines [Fe{(£b5-C5H4)-C(Me)=N-R}2]¡AR= nhexyl(2a)¡Acyclohexyl(2b)¡Aphenyl(2c)¡AN,N-dimethylethylamino(2d)¡A4-methoxyphenyl(2e)¡A4-nitrophenyl(2f)¡A3-nitrophenyl(2g)¡A2-methoxyethyl(2h) have been synthesized by reaction of 1,1¡¦-diacetylferoocene and the corresponding amines through condensation reaction. Solid state crystal X-ray structural analysis revealed the geometry of the ferrocene derivatives are various with the different substituents . In addition, these ferrocene derivatives might coordinate with CuBr to form a series of iminoferrcenyl copper(¢¹) complexes. Solid state crystal X-ray structural analysis revealed the iminoferrcenyl copper(¢¹) complexes 3a~3d showed monomeric or dimeric geometry and diiminoferrcenyl copper(¢¹) complexes 4a~4d exhibited polymeric or dimeric geometry. All synthesized ferrocenylimine and1,1¡¦-ferrocenyldiimines derivatives exhibited a reversible one ¡Velectron redox process in their cyclic voltammograms, and the values of their redox potentials relied on the R groups. The correlation between the redox potential and the Hammett substituent constant, £mp was quite well, with a correlation coefficient of 0.96 in CH2Cl2 and CH3CN. According to the cyclic voltammograms, iminoferrocenyl copper complexes showed that the substituents on the imino parts strongly affect the redox potentials of the iron centers in the ferrocenyl segments as well as the copper metal center. The Cu+/Cu2+ couple redox potentials are in the range of 0.269V and 0.719V dependent on solvent effect. The iminoferrocenyl copper complexes¡¦s UV-vis absorption seems to be red shift comparing with iminoferrocene. In the CH2Cl2, compound 3a¡B3b¡B4d shows emission at £fmax ~ 408 nm . In the CH3CN, compound 3a¡B3b¡B3c¡B3d¡B4a¡B4b and 4c show the blue shift emission band comparing with iminoferrocenyl copper complexes in CH2Cl2. In addition, complex 4d in CH2Cl2 and complex complex 3d in CH3CN showed higher quantum yield value. Moreover, compound 1a and 2a combined with CuBr exhibit good catalytic activity and controlling ability in the MMA ATRP process.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 141-142). Also available on the Internet.

Reproduction de : Thèse doctorat : Mécanique des fluides : Toulouse, INPT : 1996. / Titre provenant de l'écran-titre. Bibliogr. 94 réf.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 141-142). Also available on the Internet.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 65-72). Available also in a digital version from Dissertation Abstracts.

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