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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Design and synthesis of volatile compounds for chemical vapor deposition of electronic materials

Matthews, Jason Shastri 05 1900 (has links)
No description available.
32

Studies of some volatile compounds of main group elements

Aldridge, Simon January 1996 (has links)
Methylzinc tetrahydroborate, [MeZnBH<sub>4</sub>], has been prepared by two routes and the structure of the solid determined by X-ray crystallography to reveal helical polymers in which MeZn and BH<sub>4</sub> units alternate. The latter functions as a bidentate ligand with respect to each of the adjacent metal atoms. Investigation by mass spectrometry and matrix isolation shows that the vapour consists of an equilibrium mixture of monomeric and dimeric species. The pattern of infrared bands for the monomer is characteristic of a bidentate BH<sub>4</sub> group, a finding consistent with the results of DFT calculations. Disproportionation into [Me<sub>2</sub>Zn] and [Zn(BH<sub>4</sub>)<sub>2</sub>] is a common feature of the chemistry of methylzinc tetrahydroborate, although it has been possible to isolate and characterize the adduct [MeZnBH<sub>4</sub>.SMe<sub>2</sub>]. The reaction between [B<sub>4</sub>H<sub>10</sub> and [Me<sub>2</sub>Zn] in the gas phase affords colourless acicular crystals of [(MeZn)<sub>2</sub>B<sub>3</sub>H<sub>7</sub>] in yields of ca. 10%. This compound has been characterized by chemical analysis and by NMR and vibrational spectroscopy. X-ray crystallography reveals that the product is a dimer, [(MeZn)<sub>2</sub>B<sub>3</sub>H<sub>7</sub>]<sub>2</sub>, featuring two distinct zinc environments. Two B<sub>3</sub>H<sub>7</sub>ZnNe ligands, formally derived from B<sub>3</sub>H<sub>8</sub> by replacement of a µ<sub>2</sub>-H by a µ<sub>2</sub>-ZnMe unit, each function in a bis(bidentate) manner linking together two other MeZn centres through pairs of Zn-H-B bridges. The structures of several aluminium tetrahydroborates in the solid phase have been investigated by X-ray diffraction. The structure of dimethylaluminum tetrahydroborate has been shown to consist of helical polymeric chains in which Me<sub>2</sub>-Al and BH<sub>4</sub> units alternate. Here, too, the BH<sub>4</sub> groups exhibit bidentate ligation with respect to each of the adjacent metal atoms, although the degree of interaction between the metal centre and the BH<sub>4</sub> group is somewhat less than in [MeZnBH<sub>4</sub> ]. Solid aluminium tris(tetrahydroborate) exhibits two phases with a transition temperature in the range 180-195 K. Each phase is made up of discrete Al(BH <sub>4</sub> )<sub>3</sub> units, the principal differences relating to the packing of the individual molecules. In the a phase the Al(BH <sub>4</sub> )<sub>3</sub> molecules display an angle of 78.2° between the AlB<sub>3</sub> and Al(µ-H)<sub>2</sub> planes and are disposed about a 2<sub>1</sub> crystallographic screw axis; in the ß phase the molecular units conform to D<sub>3h</sub> symmetry. Dimethylindium octahydrotriborate, [Me<sub>2</sub> lnB<sub>3</sub> H<sub>8</sub> ], has been synthesized by the reaction between trimethylindium and tetraborane(10) and characterized by chemical analysis and by NMR and vibrational spectroscopy. X-ray diffraction of a single crystal reveals that the solid consists of [Me<sub>2</sub> lnB<sub>3</sub> H<sub>8</sub>] units, although there is evidence of charge separation in the sense [Me<sub>2</sub>ln]<sup>+</sup>[B<sub>3</sub> H<sub>8</sub> ]<sup>-</sup> and of secondary interaction between terminal hydrogen atoms and adjacent indium centres. The infrared spectrum of the matrix-isolated vapour is consistent with a monomeric structure similar to that of [Me<sub>2</sub> AlB<sub>3</sub> H<sub>8</sub>].
33

Modelling radon-222 as a proxy for vapour phase transport in the unsaturated zone

Gibbons, Deirdre January 2000 (has links)
No description available.
34

Mathematical modelling of large low-rank coal particle devolatilization /

Heidenreich, Craig. January 1999 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Chemical Engineering, 1999. / Includes bibliographical references (leaves 322-335).
35

Semi-volatile organic compounds as molecular markers for atmospheric and ecosystem transport /

Genualdi, Susan A. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.
36

Biodegradation of paint VOC mixtures in biofilters

Park, Jung Su, Kinney, Kerry A., January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Kerry A. Kinney. Vita. Includes bibliographical references.
37

Novel membrane inlet mass spectrometric methods for analysis of organic compounds in aqueous and solid samples /

Ojala, Marja. January 2001 (has links) (PDF)
Thesis (doctoral)--University of Helsinki, 2002. / Includes bibliographical references. Also available on the World Wide Web.
38

Part I: from the lab to the field - recent developments in polymer coated ATR sensing for the determination of volatile organic compounds. Part II: from the field to the lab - investigating IR signatures for remote sensing applications

Karlowatz, Manfred. January 2004 (has links) (PDF)
Thesis (Ph. D.)--School of Chemistry and Biochemistry, Georgia Institute of Technology, 2005. Directed by Boris Mizaikoff. / Weck, Marcus, Committee Member ; Lyon, Andrew, Committee Member ; Loeffler, Frank, Committee Member ; Janata, Jiri, Committee Member ; Mizaikoff, Boris, Committee Chair ; Orlando, Thomas, Committee Member. Includes bibliographical references.
39

In-home formation of halogenated volatile organic compounds (VOCS) implications for human exposure and indoor air quality /

Olson, David Alan. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
40

Gas/solid and gas/particle partitioning of polychlorinated dibenzodioxins, polychlorinated dibenzofurans and polycyclic aromatic hydrocarbons to filter surfaces and ambient atmospheric particulate material /

Mader, Brian T. January 2000 (has links)
Thesis (Ph. D.)--Oregon Graduate Institute, 2000.

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