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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.
51

Oxygen Transport Measured by Isotope Tracing through Solid Oxides

Wood, Thomas 31 May 2011 (has links)
The following thesis demonstrates two isotope tracing experiments that measure oxygen transport through electrochemically polarized solid oxides. Cathode-symmetric ‘button’ cells with yttria stabilized zirconia(YSZ) electrolytes and either strontium doped lanthanum manganate(LSM) or composite LSM/YSZ cathodes were studied. The first experiment measured the residence time distributions(RTD) of 34O2. The measured RTDs were compared at different temperatures(700-800°C) and applied potentials(-2 to -8V). Comparisons with simulated RTDs revealed that oxygen transport was laterally heterogeneous. Delamination of the counter electrode is likely the source of the heterogeneity. The second experiment measured a wave of 18O by exposing an interior cross section and applying ToF-SIMS analysis. A depth profile was produced that spans the cathode and electrolyte interface. The depth profile was compared with a variety of limiting oxygen activation scenarios predicted by a simple 1-D model. Comparisons demonstrated that oxygen activation is likely not restricted to the cathode and electrolyte interface.
52

Detection and quantification of sub-micromolar concentrations of aqueous anions using infrared spectroscopy and mass spectrometry

Hebert, Gretchen N. January 2004 (has links)
Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.
53

Analise multielementar e isotopica em compostos de uranio por espectrometria de massa com fonte de plasma induzido ( ICPMS )

OLIVEIRA JUNIOR, OLIVIO P. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:23Z (GMT). No. of bitstreams: 1 06890.pdf: 3271433 bytes, checksum: 57399ce5f630231a9b2741455ed096f0 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
54

Uso da monitoracao ambiental como tecnica de identificacao de atividades de enriquecimento isotopico

BUCHMANN, JOSE H. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:34Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:11Z (GMT). No. of bitstreams: 1 06861.pdf: 8656275 bytes, checksum: 33d75be9bc7f27a315785b762567f56c (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
55

Avaliação da poluição atmosférica por metais na região metropolitana de São Paulo utilizando a bromélia Tillandsia usneoides L. como biomonitor

NOGUEIRA, CLAUDIO A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:06Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:50Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
56

Developments in, and applications of, capillary electrophoresis inductively-coupled plasma mass spectrometry

Taylor, Karen Anne January 1999 (has links)
This project has set out to design and optimise a robust and efficient interface for capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICP-MS) and to investigate the application of the technique in elemental speciation studies. An interface was constructed using a commercial microconcentric nebuliser (MCN) and a cyclonic spray chamber. The cyclonic spray chamber was designed specifically to provide rapid sample response and washout and to minimise sample dispersion. Isoforms of the heavy metal binding protein, metallothionein, were separated and the bound metals detected to characterise the interface. Suction from the self-aspirating nebuliser was identified as the principal factor controlling electrophoretic resolution.
57

Rastreamento da origem geográfica de amostras de maconha apreendidas nas ruas de São Paulo, por meio de assinaturas químicas

SHIBUYA, ELISA K. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:50:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:44Z (GMT). No. of bitstreams: 1 10554.pdf: 11520405 bytes, checksum: 77369e7569e528de44a78a67c7e707b6 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:00/09814-0
58

Desenvolvimento de método multirresíduo para determinação de pesticidas benzimidazóis, carbamatos e triazinas em milho por cromatografia líquida acoplada à espectrometria de massas em Tandem e sua certificação

KUSSUMI, TEREZA A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:32Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:56Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
59

Desenvolvimento de metodologia para determinacao de alguns pesticidas em aguas empregando microextracao em fase solida (SPME)

KOMATSU, EMY 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:31Z (GMT). No. of bitstreams: 1 09814.pdf: 3649987 bytes, checksum: 2ebdfca1ffee2ffc9e0dc65e2ac1df10 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
60

Desenvolvimento e avaliacao da incorporacao e liberacao de oleo de acai em hidrogeis de poli(N-vinil-2-pirrolidona / Açaí oil development and evaluation of immobilization and release in poly (N-vinyl-pyrrolidone) hydrogels

MACHADO, ANA C.H.R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:57Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:55Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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