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The Global ETD Search service is a free service for researchers
to find electronic theses and dissertations. This service is
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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.
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Filmes supercondutores do sistema YBsubaCsubuOCOELHO, 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
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Filmes supercondutores do sistema YBsubaCsubuOCOELHO, 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
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Copper-oxides catalyzed polyethylene depolymerization in a pilot-scale reactorWang, Bing January 2000 (has links)
No description available.
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Static and dynamic phases of vortices in the high temperature superconductor YBaâ†2Cuâ†3Oâ†7â†-â†#delta#Rassau, Andreas Peter January 2000 (has links)
No description available.
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Investigation of the vortex phase diagram and dynamics in single crystalline samples of the high temperature superconductor YBaâ†2Cuâ†3Oâ†7â†-â†#delta#Kokkaliaris, Stylianos January 2000 (has links)
No description available.
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Ac susceptibility and resistivity studies of YBaâ†2Cuâ†3Oâ†7â†-â†#delta# high-temperature superconductorsBracanovic, Darko January 1999 (has links)
No description available.
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Current and field distribution in high temperature superconductorsJohnston, Martin David January 1998 (has links)
No description available.
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The growth and characterisation of YBaâ†2Cuâ†3Oâ†7â†-â†#â†dâ†eâ†lâ†tâ†aâ†# superconducting thin filmsMcCurry, Martin Peter January 1999 (has links)
No description available.
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The vortex-related phase transition in YBCO thin filmsMisat, Sylvain January 1999 (has links)
No description available.
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Characterisation of superconducting Nd123 solid solutions and related phasesDuncan, Fiona Hazel January 1999 (has links)
The stoichiometry of the Nd<sub>1+x</sub>Ba<sub>2-x</sub>Cu<sub>3</sub>O<sub>7-δ</sub> solid solution has been investigated using XRD and EPMA. At 980°C in air, an essentially continuous solid solution forms with limiting compositions x<sub>min</sub> = 0.03(1) and x<sub>max</sub> = 0.92(2). The solid solution limits are independent of temperature over the range 300 to 1050°C, i.e. stoichiometric Nd123 does not form. Preliminary studies show that annealing in an Ar atmosphere does not affect x<sub>min</sub>. Three structurally distinct polymorphs of Nd123ss exist - tetragonal Nd123ss, orthorhombic Nd123ss and orthorhombic Nd123ss. The stability range of each in air has been determined. Quenched samples with 0.03 ≤ x ≤ 0.6 have the tetragonal Nd123ss structure. On oxygenation, samples with 0.03 ≤ x <0.2 are orthorhombic. The orthorhombic-tetragonal phase transition is second order, both with increasing temperature and increasing x. Samples with 0.7-0.9 have the orthorhombic Nd213ss structure at all oxygen contents. Tetragonal Nd123ss is isostructural with tetragonal Y123 and orthorhombic Nd123ss is isostructural with orthorhombic Y123. Orthorhombic Nd213ss has the ideal stoichiometry Nd<sub>2</sub>BaCu<sub>3</sub>O<sub>7-δ</sub> and is based on a 2a x b x 2c superstructure of the Nd123ss structure. The supercell is due to ordering of the Nd and Ba atoms, which leads to ordering of the oxygen atoms. Melting temperatures decrease with x. Two distinct regions of melting behaviour are observed; the first for 0.03 ≤ x ≤ 0.6 with a thermal minimum at x0.4, and the second for 0.7 ≤ x ≤ 0.9. Oxygen contents increase with x. Samples with larger x values have a smaller range of oxygen contents. High pressure oxygen annealing results in a constant Cu valence state of 2.35 for all values of x. Average copper valence states <2 are only obtained readily for x ≤ 0.3. T<sub>c</sub> decreases with x and samples become non-superconducting at x0.5. For samples annealed in 1 bar O<sub>2</sub>, 'double plateau' behaviour is observed.
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