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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.
601

Avaliacao dosimetrica da solucao fricke gel usando a tecnica de espectrofotometria para aplicacao na dosimetria de eletrons e neutrons / Dosimetric evaluation of the fricke gel dosimeter using the spectrophotometric technique for application in electron and neutron dosimetry

MANGUEIRA, THYAGO F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:05Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
602

Estudo da influencia do campo magnetico na resistencia a corrosao em imas permanentes de Nd=Fe-B

OLIVEIRA, MARA C.L. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:34Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:22Z (GMT). No. of bitstreams: 1 09675.pdf: 5315534 bytes, checksum: 8697e231fcc0636d3cbf06b636bc5b95 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
603

Caracterização magnética e microestrutural de ímãs sinterizados de Pr-Fe-B processados pela técnica de transferência de pós e utilizando decrepitação por hidrogênio

SOARES, EDSON P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:50:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:56Z (GMT). No. of bitstreams: 1 10449.pdf: 4731393 bytes, checksum: e712ff415dbc885976e03c8cf9a7af16 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
604

Estudo microestrutural e propriedades magnéticas em imãs permanentes sinterizados à base de PrFeCoBNb com adições de elementos de liga / Microstructural study and magnetic properties of PrPeCoBNb-based permanent sintered magnets with alloy additions

MENDES NETO, TEOFILO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:41Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
605

Efeito da adição de óxido de zinco e de óxido de boro nas propriedades de zirconato de bário dopados com ítrio / Effect of zinc oxide and boron oxide addition on the properties of yttrium-doped barium zirconate

ANDRADE, TIAGO F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:23Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:31Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
606

Componentes derivados de venenos de serpentes com ação antitumoral em células de melanoma murino / Snake venoms components with antitumor activity in murine melanoma cells

QUEIROZ, RODRIGO G. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:11Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
607

Caracterização do campo de nêutrons na instalação para estudo e, BNCT no reator IEA-R1 / Neutron field characterization in the installation for BNCT study in the IEA-R1 reactor

CARNEIRO JUNIOR, VALDECI 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:52Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP
608

Estudo eletroquimico da co-reducao de KBFsub4 e Ksub2 TIFsub6 em meio de uma mistura eutetica de LiF-NaF-KF para a obtencao do diboreto de titanio [TIB sub 2]

ETT, GERHARD 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:43:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:02Z (GMT). No. of bitstreams: 1 06778.pdf: 10838321 bytes, checksum: da09e815b4eb68ff38370a4f1987faaa (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
609

Avaliacao do efeito de tratamentos superficiais na resistencia a corrosao de magnetos de Nd-Fe-B / Assessment of the effect of surface treatments on the corrosion resistance of Nd-Fe-B Magnets

MARTINS, EMERSON A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:32Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:42Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
610

Obtenção e evolução da fase icosaedral quasicristalina em ligas Al-Cu-Fe e Al-Cu-Fe-B por Melt-Spinnin / OBTAINING AND EVOLUTION OF PHASE ICOSAHEDRAL QUASICRISTALINA IN ALLOYS Al-Cu-Fe AND Al-Cu-Fe-B BY MELT-SPINNING

Feitosa, Francisco Riccelly P. 03 March 2009 (has links)
Made available in DSpace on 2015-05-08T14:59:46Z (GMT). No. of bitstreams: 1 parte1.pdf: 1839351 bytes, checksum: 34e86046fc8cf8f52125675d2e7267f6 (MD5) Previous issue date: 2009-03-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Melt spinnng processing is one of the most common processes to obtaining quasicrystaline structures. This is because of the fast cooling rate it imposes on the system, favoring such type of structure. This work deals with the production of quasycristaline phases (Al60Cu27,5Fe12,5 e Al57Cu27,5Fe12,5B3) via melt-spinning. The alloys were initially cast via induction melting under atmospheric air, with the designed chemical composition of the quasicrystals. Hence, the ribbons were produce by melt-spinning were characterized by means of x-ray diffraction and scanning electron microscopy. The results indicate that the icosahedral ψ - Al65Cu20Fe15 phase formed in both types of starting compositions. It seams that the boron contributes to stabilize the icosahedral phase. / O processo melt-spinning por imprimir altas taxas de resfriamento, é um dos principais meios para a obtenção de ligas com estrutura quasicristalinas, sendo o primeiro método utilizado para produzir materiais quasicristalinos. Neste trabalho utilizou-se este processo para a elaboração das ligas quasicristalinas Al(60-x)Cu25Fe15Bx, Al(60-x)Cu27,5Fe12,5Bx e Al(65-x)Cu20Fe15Bx (x=0 e x=3%at de boro). As ligas foram previamente fabricadas, por fusão, em atmosfera de argônio, em forno à indução, para em seguida serem submetidas ao processo melt-spinning , onde se obteve o material na forma de fita. As amostras foram caracterizadas por difração de raios-x e microscopia eletrônica de varredura. Os resultados indicaram a formação da fase icosaedral ψ - Al65Cu20Fe15 nas composições estudadas e uma provável contribuição do boro na produção dessa fase icosaedral

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