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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.
441

Fingerprints of Volatile Organic Compounds from Stationary Sources and the Ozone Formation Potentials in the Kaohsiung Area

Wu, Li-Yen 26 June 2002 (has links)
ABSTRACT Being a densely populated and heavily industrialized harbor, the emissions of air pollutants in the Kaohsiung area are very huge. There is substantial amount of VOCs (volatile organic compounds) present in the ambient air. Furthermore, relative high temperature and strong sunlight tend to transform these VOCs to oznone, causing high ozone episodes. This study aimed to determine the VOCs source profiles (or fingerprints) from 20 stationary sources, 10 from each of Kaohsiung City and Kaohsiung County. These include flue gas emission from incineration plants, sewage treatment plants, petroleum plants, and others. The samples was collected using a stainless-steel thermal desorption tube, then analyzed a Hewlett-Packard 58900-II gas chromatograph, fitted with a flame ionization detector and desk-top personel computer. The OFP (ozone formation potential) of VOCs from individual sources were evaluated based on MIR (maximum incremental reactivities). The results show that the speciations of VOCs depend on the raw material and air pollution control equipments used in the processes. The major VOCs in the petro-chemical industries are benzene, toluene, xylene, and 1,3,5-trimethylbenzene. The major VOCs in the PVC processes and surface-painting industries are 2-methylbutane, 2-methylpentane, and ethylbenzene. The major VOCs in the sewage treatment plants are ethylene, hexane, benzene, toluene, and m-xylene. The highest average reaction of the samples is 27.94 g-O3/g-VOCs from intermediary process, the next are from lubrication oil distillation tower, TPE process, ABS process, and maleic anhydride process, ranging from 3 ~ 5 g-O3/g-VOCs. Thus, the reactivity of aromatic-related process is highest, the next are aldehydes - and ketones -related processes. Keywords: Volatile Organic Compounds, Fingerprints, Ozone Formation Potential
442

Geoarchaeological investigation of natural formation processes to evaluate context of the clovis component at the Gault site (41BL323), Bell County, Texas

Alexander, Dawn Aileen Joyce 10 October 2008 (has links)
Texas A&M University completed excavations at the Gault site (41BL323) in Bell County, Texas, in the spring season of 2000. Located at the head of Buttermilk Creek, past inhabitants have enjoyed perennial springs and a variety of natural resources available in the immediate area, including high quality chert from the Balcones Escarpment of the Edwards Plateau. Chipped stone material diagnostic of the Clovis period was recovered during the TAMU block excavation, informally referred to as the "Lindsey Pit," from clay deposits approximately 35 cm thick. Natural agents that may have impacted contextual integrity of the Clovis cultural deposits include stream action, pedoturbation, and bioturbation. Artifact spatial analyses examined long axis orientations and artifact degree of dip to identify non-random patterns that would result from stream action. Vertical and horizontal relationships of refitting artifacts were examined to evaluate post-depositional displacement. Orientations of chipped stone artifact long axes and inclination were found to be statistically random, with minor patterns that reflect the paleotopography. Thirty-three groups of refitting artifacts were identified, none of which contained elements recovered from deposits more recent than the Clovis clays. Five groups have elements that appear to come from both of the Clovis clay deposits, indicating a small degree of vertical displacement. The results of this research indicate the clays bearing Clovis materials retained a high degree of integrity such that the spatial patterns preserved in the archaeological record at this location are the result of cultural activities and not natural processes. Though time-consuming in the field and laboratory, additional fine-grained analyses such as artifact orientation and refit studies provide separate lines of evidence to account for natural processes that may have acted to obscure the original patterns of the archaeological record, and our understanding of past human cultures.
443

Orientation professionnelle des adultes et relation éducative la pratique des Maisons de l'information sur la formation et l'emploi (MIFE) /

Berjon, Agnès. Avanzini, Guy. January 2001 (has links)
Thèse de doctorat : Sciences de l'éducation : Lyon 2 : 2001. / Titre provenant de l'écran-titre. Bibliogr.
444

Formation continue et initiation étude de trois formations /

Babin, Marc. Avanzini, Guy. January 1999 (has links)
Thèse de doctorat : Sciences de l'éducation : Lyon 2 : 1999. / Titre provenant de l'écran-titre. Bibliogr. (82 ref.).
445

Approche comparative de la fonction de médiateur de presse dans les quotidiens brésilien Folha de Sao Paulo e français Le Monde par

Ferreira Maia, Kenia Beatriz. Walter, Jacques January 2008 (has links) (PDF)
Reproduction de : Thèse doctorat : Perspectives interculturelles. Ecrits, médias, espaces et sociétés : Metz : 2003. / Titre provenant de l'écran-titre. Notes bibliographiques.
446

La formation professionnelle des immigrés en France attentes, stratégies et enjeux /

Ayachi, Annouar Vieille-Grosjean, Henri. January 2009 (has links) (PDF)
Thèse de doctorat : Sciences de l'éducation : Strasbourg 1 : 2008. / Titre provenant de l'écran-titre. Bibliogr. p. 256-258.
447

Building for the future sharpening the tools of spiritual formation in the Québec evangelical context /

Whatley, Barry M., January 2000 (has links)
Thesis (D. Min.)--Gordon-Conwell Theological Seminary, Charlotte, NC, 2000. / Abstract and vita. Includes bibliographical references (leaves 283-296).
448

CFD simulation of soot formation and flame radiation

Lautenberger, Christopher W. January 2002 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: soot formation; FDS; flame radiation; soot oxidation; field modeling; diffusion flames; soot. Includes bibliographical references (p. 14-15).
449

Soil formation on the Namaqualand coastal plain /

Francis, Michele Louise. January 2008 (has links)
Dissertation (PhD(Agric))--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet
450

Interpersonal affirmation: How close others influence self-authenticity.

DiDonato, Theresa E. January 2008 (has links)
Thesis (Ph.D.)--Brown University, 2008. / Vita. Advisor : Joachim I. Krueger.

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