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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.
71

Evaluation of yttrium-doped SrTiO3 as a solid oxide fuel cell anode /

Hui, Shiqiang January 2001 (has links)
Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references. Also available via World Wide Web.
72

Production and characterisation of novel kinds of cluster matter and their behaviour under the influence of hydrogen and oxygen

Bour, Giorah. Unknown Date (has links) (PDF)
Techn. Hochsch., Diss., 2003--Aachen.
73

Messung und Analyse neutroneninduzierter Aktivitäten in Materialien zukünftiger Kernfusionsreaktoren

Eichin, Randy. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2004--Dresden.
74

Influencia da microestrutura na tenacidade a fratura e resistencia a flexao da zirconia tetragonal policristalina

BASANI, HOMERO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:08Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:40Z (GMT). No. of bitstreams: 1 01908.pdf: 6409813 bytes, checksum: a4da653568b2a1fde0228c02cc3838b9 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
75

Síntese, caracterização e estudo termoanalítico dos mandelatos de lantanídeos(III), exceto o promécio, e de ítrio(III) no estado sólido

Gigante, Andréa Cristina [UNESP] 21 March 2014 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-21Bitstream added on 2014-12-02T11:21:04Z : No. of bitstreams: 1 000774878_20150321.pdf: 503929 bytes, checksum: 39ee2d23c6cdfba5667bdbc9462f7401 (MD5) Bitstreams deleted on 2015-03-27T11:50:05Z: 000774878_20150321.pdf,Bitstream added on 2015-03-27T11:50:37Z : No. of bitstreams: 1 000774878.pdf: 3285029 bytes, checksum: f9278189a2600465588ac1ce4e4a2608 (MD5) / No presente trabalho foram sintetizados em solução aquosa os compostos Ln(L)3nH2O – onde Ln representa os íons lantanídeos trivalentes (La ao Lu, exceto o promécio) e o ítrio(III) e L representa o íon mandelato (C6H5CH(OH)CO2 -)). Os compostos foram sintetizados por lenta adição de quantidades estequiométricas do ligante mandelato de sódio nas respectivas soluções de cloretos ou nitratos de lantanídeos e de ítrio, sob agitação contínua. A formação dos compostos de lantânio ao neodímio foi verificada após a manutenção das soluções em ebulição durante 30 minutos. Após a sua filtração, observou-se grande perda por solubilidade destes compostos durante a lavagem dos seus precipitados, sendo obtidas apenas pequenas quantidades dos mesmos. Devido a isso, foi realizada nova preparação destes compostos por meio da reação dos seus respectivos carbonatos com o ácido mandélico em ligeiro excesso. Já para os compostos de samário ao lutécio e ítrio a precipitação ocorreu de forma instantânea assim que se adicionou o ligante aos cloretos dos respectivos íons metálicos. A caracterização dos compostos no estado sólido foi realizada através da utilização das seguintes técnicas: complexometria; difratometria de raios X pelo método do pó; espectroscopia de reflectância total atenuada na região do infravermelho; termogravimetria e análise térmica diferencial simultâneas (TG–DTA); termogravimetria e termogravimetria derivada (TG/DTG); termogravimetria e calorimetria exploratória diferencial simultâneas acopladas à espectroscopia de absorção na região do infravermelho com transformada de Fourier (TG-DSC/FTIR) e calorimetria exploratória diferencial (DSC). Estas técnicas forneceram informações sobre a estequiometria, a desidratação, os sítios de coordenação, o comportamento térmico, composição e estrutura dos compostos sintetizados. Com os resultados obtidos pelas curvas TG e pela... / In the present work, the compounds Ln(L)3nH2O – where Ln represents trivalent lanthanide (La to Lu, except promethium) and yttrium(III) ions and L is mandelate (C6H5CH(OH)CO2 -)) – have been synthesized. The compounds were synthesized by stoichiometric addition of the sodium mandelate ligand to the respective solutions of chloride or nitrate lanthanides and yttrium, slowly with stirring. The formation of the lanthanum to neodymium compounds occurred after maintaining the solutions under ebullition for 30 minutes. After filtration, due to a great loss during the washing of these precipitates, small quantity of these mandelates were obtained. Thus, the same were also prepared by neutralization of the respective lanthanide carbonates with mandelic acid in slight excesso. The characterization of these compounds in solid state was performed using the following techniques: complexometry; X-ray powder diffractometry; infrared spectroscopy; simultaneous thermogravimetry and differential thermal analysis (TG–DTA); thermogravimetry and derivative thermogravimetry (TG/DTG); simultaneous thermogravimetry and differential scanning calorimetry coupled to absorption spectroscopy in the infrared region with Fourier transform (TG-DSC / FTIR) and differential scanning calorimetry (DSC). These techniques provided information about stoichiometry, dehydration, coordination sites, thermal behavior, composition and structure of synthesized compounds. From TG curves and complexometry results, a general formula could be established for these compounds in the solid state. The X-ray powder patterns pointed out that the synthesized compounds have a low crystalline structure and evidence concerning the formation of isomorphous series. The infrared spectroscopy data suggest that the mandelate ion acts as a chelating bidentate ligand towards the metal ions considered in this work, with a prominently ionic character. The TG–DTA and DSC curves provided...
76

Estudo para a determinacao de Samario, Europio, Terbio, Disprosio e Itrio em matriz de oxido de Gadolinio por espectofotometria de absorcao atomica

CAIRES, ANTONIO C.F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:56Z (GMT). No. of bitstreams: 1 02298.pdf: 1286663 bytes, checksum: ed62610cdfd3bfac1a6ef998fc9615de (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
77

Determinacao da eficiencia quantica de luminescencia di LiYF4:Nd+3 utilizando a espectroscopia fotoacustica

FRANCA, ECIO J. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:21Z (GMT). No. of bitstreams: 1 11280.pdf: 1220479 bytes, checksum: 742330818e5ef1d5873aaac2cc8ca3b4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
78

Filmes supercondutores do sistema YBsubaCsubuO

COELHO, ALVARO L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:10Z (GMT). No. of bitstreams: 1 01819.pdf: 965861 bytes, checksum: 0c698783e4fc27b453a2c0225bd8ff99 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
79

Obtencao e caracterizacao de ceramicas de ceria com dupla dopagem

TADOKORO, SANDRA K. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:52Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:36Z (GMT). No. of bitstreams: 1 09984.pdf: 10774307 bytes, checksum: a193fefe92c978f1963dcaad657ea1e2 (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:00/08908-1
80

Aplicacao conjunta de analise por ativacao e diluicao isotopica a determinacao dos elementos de terras raras em oxido de itrio

ATALLA, LAURA T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:24:20Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:28Z (GMT). No. of bitstreams: 1 00288.pdf: 1133493 bytes, checksum: cc3bee26beefe753c5695b8f356ce09e (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

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