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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.
81

Nitrogen Transport and Connectivity in two Wetland-Rich Boreal sites in the Athabasca Oil Sands Region, Canada

Cherry, Mikaela 13 January 2016 (has links)
Development of the Athabasca Oil Sands Region (AOSR) has increased atmospheric nitrogen emissions, a trend which is expected to increase in the future. The area surrounding development is comprised of Boreal upland forests and peatlands. Improved understanding of the hydrological connectivity between Boreal peatlands and uplands is needed to predict the fate and transport of atmospheric N deposited across the region. Two field sites: Jack Pine High (JPH, located 45 km north of Fort McMurray) and Mariana Lakes (ML, located 100 km south of Fort McMurray) were instrumented with piezometers nests and water table wells for this study (n= 108 sampling locations). The wells were placed along transects that cover target landscape units (bog, fen, upland). Wells were sampled for water isotopes and geochemical parameters during the summers of 2011-2014 to characterize the baseline geochemistry of groundwater in the different landscape units. Inorganic (nitrate, ammonium) and organic forms of nitrogen (dissolved organic nitrogen), major and minor ions and water isotope tracers (18O, 2H and 3H) were measured to identify the various forms of nitrogen in the different landscape units, as well as to assess connectivity and potential for nitrogen transport between the different units. At JPH surface and groundwater flow is from the uplands to the fen. There was little (<0.1-1.5 mg/L) nitrate, ammonium, or dissolved organic nitrate (DON) found throughout JPH. At ML nitrogen concentrations were higher (<0.1-30 mg/l) and concentrations of ammonium and DON increased at depths throughout ML. The distribution of 3H with depth within the peatland reveals limited connectivity between the peat and underlying mineral soils. Tritium sampling at ML indicates that at some locations the wetland residence time is greater than 50 years. Nitrogen movement out of peatlands may take longer due to conversions and storage. At ML nitrogen (NH4 and DON) is produced and stored at depth in the wetlands. At JPH higher nitrogen concentrations are found in the shallow groundwater of the fen. Increases in nitrogen inputs to JPH and ML are likely to be utilized by plants, but dramatic changes to the peatland may cause stored nitrogen to become mobile. / Graduate
82

Calculo dos parametros de separacao de uma centrifuga a contracorrente com variacao axial do fluxo interno

MIGLIAVACCA, SYLVANA C.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:46Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:32Z (GMT). No. of bitstreams: 1 04246.pdf: 1952463 bytes, checksum: fa9b00e6cc85c03466e3dfe096bbcf90 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
83

Preparacao de gerador de indio-113m

HO, WOUI L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:52Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:22Z (GMT). No. of bitstreams: 1 00377.pdf: 1144428 bytes, checksum: ff90dddba23a57911d88d08a78e8557f (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
84

Estudo da determinacao de cobre por analise por diluicao isotopica subestequiometrica

FAQUIM, ELAINE de S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:33Z (GMT). No. of bitstreams: 1 05657.pdf: 4842908 bytes, checksum: 494ca773331866a32eca85a48d2e214c (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
85

Distribuicao biologica de heparina marcada com CR-51 .Estudos farmacocineticos com auxilio da analise compartimental

ALMEIDA, MARIA A.T.M. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:04Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:20Z (GMT). No. of bitstreams: 1 11269.pdf: 1856747 bytes, checksum: b76814c0b5cd3ff897d8e9bb0f9b3990 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
86

Calculo dos parametros de separacao de uma centrifuga a contracorrente com variacao axial do fluxo interno

MIGLIAVACCA, SYLVANA C.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:46Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:32Z (GMT). No. of bitstreams: 1 04246.pdf: 1952463 bytes, checksum: fa9b00e6cc85c03466e3dfe096bbcf90 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
87

Preparacao de gerador de indio-113m

HO, WOUI L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:52Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:22Z (GMT). No. of bitstreams: 1 00377.pdf: 1144428 bytes, checksum: ff90dddba23a57911d88d08a78e8557f (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
88

Estudo da determinacao de cobre por analise por diluicao isotopica subestequiometrica

FAQUIM, ELAINE de S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:33Z (GMT). No. of bitstreams: 1 05657.pdf: 4842908 bytes, checksum: 494ca773331866a32eca85a48d2e214c (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
89

Distribuicao biologica de heparina marcada com CR-51 .Estudos farmacocineticos com auxilio da analise compartimental

ALMEIDA, MARIA A.T.M. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:04Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:20Z (GMT). No. of bitstreams: 1 11269.pdf: 1856747 bytes, checksum: b76814c0b5cd3ff897d8e9bb0f9b3990 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
90

The effect of structure on kinetic isotope effects

Goodall, D. M. January 1965 (has links)
No description available.

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