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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

Desenvolvimento de método de medição das espessuras de núcleos e revestimentos de placas combustíveis / Development method for measuring thickness of nuclei and coating of fuel plates

BORGES JUNIOR, REINALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:10Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
52

Desenvolvimento de metodos de medida de atividade de radionuclideos utilizados em medicina nuclear - aplicacao na padronizacao do sup(51) Cr e sup(153) Sm

LAVRAS, WILSON de O. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:39Z (GMT). No. of bitstreams: 1 08346.pdf: 3889708 bytes, checksum: 998810087525503d37c9b42eac89fcec (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
53

Datacao de pecas arqueologicas pelo metodo termoluminescente

SZMUK, PETER R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:23:35Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:59Z (GMT). No. of bitstreams: 1 01126.pdf: 2703621 bytes, checksum: c9690fe8a870c90938ebd51a03303dc6 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Fisica, Universidade de Sao Paulo - IF/USP
54

Aplicacao do metodo dos elementos finitos na solucao da equacao de difusao em estado estacionario

ONO, SHIZUCA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:31:02Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:48Z (GMT). No. of bitstreams: 1 01368.pdf: 3640499 bytes, checksum: ccba7944ce0eb5025a31bde960ef457a (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
55

Medidas de desgaste em aco inoxidavel AISI 316 por meio de ativacao superficial em ciclotron

SUMIYA, LUIZ C. do A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:30Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:38Z (GMT). No. of bitstreams: 1 06900.pdf: 5199147 bytes, checksum: 04b402ce42beb81a3094fe2294696f9f (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
56

Descricao, caracteristicas e desempenho de um prototipo de contador de corpo inteiro para uso clinico

KIEFFER, JULIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:23:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:36Z (GMT). No. of bitstreams: 1 00617.pdf: 4446323 bytes, checksum: 2472e6b6e02afc6e4ba94b64e17ccf87 (MD5) / Tese (Doutoramento) / IEA/T / Faculdade de Medicina, Universidade de Sao Paulo - FM/USP
57

Desenvolvimento de método de medição das espessuras de núcleos e revestimentos de placas combustíveis / Development method for measuring thickness of nuclei and coating of fuel plates

BORGES JUNIOR, REINALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:10Z (GMT). No. of bitstreams: 0 / Um dos componentes mais importantes de um Reator Nuclear é o Combustível Nuclear. Atualmente, o mais avançado combustível comercial, cuja aplicabilidade nos reatores brasileiros vem sendo desenvolvida pelo IPEN desde 1985, é o siliceto de urânio U3Si2. Este é formado por placas combustíveis com núcleos de dispersão (onde o material físsil (U3Si2) é disperso homogeneamente em uma matriz de alumínio) revestidos por alumínio. Tal combustível é produzido no Brasil com tecnologia totalmente nacional, resultado do esforço realizado pelo grupo de fabricação de combustíveis nucleares (CCN Centro do Combustível Nuclear) do IPEN. Diante da necessidade do aumento da potência do reator IEA-R1 e da construção do Reator Multipropósito Brasileiro (RMB), para a produção de radioisótopos principalmente para fins na área da medicina , haverá significativo aumento na produção deste combustível nuclear no IPEN. Em face desta conjuntura, faz-se necessário o desenvolvimento de técnicas de qualificação mais modernas e automatizadas. Visando a este objetivo, neste trabalho foi desenvolvido um novo método computacional de medição de espessuras de núcleos e revestimentos de placas combustíveis, o qual é capaz de realizar tais medidas em tempo menor e com dados estatísticos mais significativos, quando comparado com o método atual de medição. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
58

Desenvolvimento de metodos de medida de atividade de radionuclideos utilizados em medicina nuclear - aplicacao na padronizacao do sup(51) Cr e sup(153) Sm

LAVRAS, WILSON de O. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:39Z (GMT). No. of bitstreams: 1 08346.pdf: 3889708 bytes, checksum: 998810087525503d37c9b42eac89fcec (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
59

Photomodulated reflectance spectroscopy of novel semiconductor materials

Rowland, Gareth Llywelyn January 1999 (has links)
Room temperature photomodulated reflectance (PR), Photoluminescence (PL) and double crystal x-ray diffraction (DCXRD) measurements have been performed on a series of tensilely strained InxGa1-xAs (0.316 ≤ x ≤ 0.533) multiple quantum well (QW) structures, with In0.80Ga0.20As0.43P0.57 barriers. The DCXRD measurements provided accurate information on composition, strain and layer thickness, while PR was used to determine the energies of the full manifold of allowed and forbidden critical point interband QW transitions. A three-band effective mass formalism was used to model the QW transitions to derive structural information on each sample. The energies of the ground-state QW transitions, H11 and L11, were found to increase with tensile strain, becoming degenerate near 0.36% tensile strain. Room temperature PR and conventional reflectance (R) measurement have been performed on two I.R. emitting InGaAs/GaAs/A1As vertical cavity surface emitting laser (VCSEL) structures. The R measurements were modelled using a transfer matrix formalism to determine errors in the growth fluxes. A new PR lineshape model has been developed based on energy dependent Seraphin coefficients, to describe the cavity mode interaction with a confined-state QW transition. The model is demonstrated on a set of PR spectra, and used in a novel way to derive the Deltaepsilon2 spectrum of the QW layers directly. The results are compared with those taken of the QW layers directly after removing the top Bragg stack reflector. Whilst the QW layers in one sample were found to be close to nominal, the in composition of QW in the other sample was found to depart significantly from the nominal 23%, and was found to be 28%. Room temperature and ~ 80K PR measurements were performed on three InAs/GaAs self-assembled quantum dot (QD) structures: a sample with a single layer of QDs, and two with two layers. The PR revealed five equally spaced confined-state QD transitions, at both 80K and room temperature, with ~ 54 meV separation. The behaviour of the QD1 transition as a function of temperature was investigated and an anomalous increase in linewidth was observed on cooling. Annealing of one of the samples produced a strong blue shift (~ 250 meV) and narrowing of the QD transitions.
60

Bezkontaktní měření v procesním inženýrství / Contactless measuring in process engineering

Lavický, Jiří January 2010 (has links)
The objective of my thesis is description of contactless measuring methods, their principle and distribution. There are compiled basic facts about the measurement of laser and ultrasound. In this work is also described non-contact temperature measurement. Part of thesis is non-contact flow measurement on the model.

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