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81	Characterisation of superconducting Nd123 solid solutions and related phases Duncan, 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. 530.41
82	Estudo do processo de obtencao da liga magnetica NDsub(15) FEsub(77) Bsub(8) por reducao-difusao (R/D) calciotermica GUILHERME, ENEIDA da G. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:36:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:02Z (GMT). No. of bitstreams: 1 04373.pdf: 5945321 bytes, checksum: 2ab6ce764052bcd601cde1fffb3f7feb (MD5) / Disserta‡ao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP neodymium alloys reduction diffusion iron alloys reduction diffusion boron alloys reduction diffusion
83	Avaliação da adesão de fibroblastos sobre superfícies apicectomizadas pelo laser de Er:YAG e tratadas ou não com o laser de Nd:YAG LOBATO NETO, ARCELINO de M. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:51:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:01Z (GMT). No. of bitstreams: 1 11302.pdf: 6104294 bytes, checksum: 2f6603857241226128098a3cdc3f54ff (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo Dentistry Lasers TEETH DENTIN FIBROBLASTS CELL CULTURES ADHESION ERBIUM NEODYMIUM LASERS EVALUATION
84	Alteracoes na superficie de implantes de titanio apos a irradiacao com laser de Nd:YAG ROMERA, ROGERIO F. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:28:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:27Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de Sao Paulo, Sao Paulo TEETH IMPLANTS TITANIUM NEODYMIUM LASERS PULSES SURFACES MORPHOLOGICAL CHANGES SCANNING ELECTRON MICROSCOPY OPTICAL MICROSCOPY
85	Desenvolvimento de lasers no azul, a partir da geracao de segundo harmonico de um laser de Nd:YAG operando em 946nm / Development of blue lasers, from second harmonic generation using a Nd:YAG laser emitting at 946 nm NOGUEIRA, GUSTAVO B. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:28:17Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:45Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP SOLID STATE LASERS NEODYMIUM LASERS DIODE-PUMPED SOLID STATE LASERS HARMONIC GENERATION
86	Estudos dos mecanismos envolvidos em processos de endurecimento superficial a laser de ligas a base de aluminio / Studies of the mechanisms involved in the laser surface hardening process of aluminium base alloys SILVA, LUCIANA V. da 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:28:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:02Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP ALUMINIUM BASE ALLOYS SILICON ALLOYS SURFACE TREATMENTS HARDENING NEODYMIUM LASERS PULSES MICROSTRUCTURE MECHANICAL PROPERTIES
87	Estudo in vitro do uso do laser de Nd:YAG na permeabilidade dentinaria cervical MAGALHAES, MANOELITA F. de 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:46:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:17Z (GMT). No. of bitstreams: 1 07685.pdf: 7530747 bytes, checksum: e5dd91c203e5e13ff29c72d4f86260f5 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo dentistry lasers therapeutic uses teeth dentin morphological changes in vitro neodymium lasers
88	Obtencao de oscilacao em frequencia unica em lasers de estado solido bombeados por diodo-laser MATOS, PAULO S.F. de 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:44:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:50Z (GMT). No. of bitstreams: 1 07170.pdf: 3547961 bytes, checksum: 2b5adb1189f6eaea8048d92f88627ed4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP diode-pumped solid state lasers semiconductor diodes frequency selection oscillation modes neodymium lasers
89	Estudo in vitro da fusao de hidroxiapatita e esmalte em superficies de esmalte humano pelo laser de Nd: YAG FERREIRA, MARCUS V.L. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:44:45Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:00Z (GMT). No. of bitstreams: 1 06997.pdf: 4582469 bytes, checksum: 7c5c05e2d6d13841e0e7d53eb604c3d2 (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo Dentistry lasers neodymium lasers teeth enamels apatites calcium phosphates melting morphological changes
90	Laser de Nd:YVOsub(4) bombeado transversalmente em configuração com ângulo rasante interno CAMARGO, FABIOLA de A. 09 October 2014 (has links) Made available in DSpace on 2014-10-09T12:51:35Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:17Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:03/10164-9 NEODYMIUM LASERS DIODE-PUMPED SOLID STATE LASERS SEMICONDUCTOR DIODES CONFIGURATION CRYSTALS

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