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31	Spin injection into high temperature superconductor Severac, Childerick Henri Louis January 2000 (has links) No description available. 530.41
32	Surface Modification of a Doped BaCeO3 to Function as an Electrolyte and as an Anode for SOFCs Sano, Mitsuru, Hibino, Takashi, Tomita, Atsuko January 2005 (has links) No description available. heat treatment oxidation catalysis electrical conductivity vaporisation porous materials electrochemical electrodes solid oxide fuel cells electrolytes yttrium compounds barium compounds
33	Investigation of Reactions between Barium Compounds and Tungsten in a Simulated Reservoir Hollow Cathode Environment Schoenbeck, Laura 24 March 2005 (has links) Reservoir-type dispenser hollow cathodes are currently being developed for use on NASAs Prometheus 1 mission. In these cathodes, the reaction between a barium source material and tungsten powder contained in a cavity surrounding a porous tungsten emitter produces barium vapor which is crucial to operation of the cathode. The primary objective of this research was to investigate the reactions between tungsten and a commercial barium source material in a simulated reservoir hollow cath-ode environment. Mixtures of tungsten and a barium calcium aluminate material were sealed inside molybdenum capsules with porous tungsten closures and heated to 1000?1200?and 1300?or 100, 200, and 400 hours. Based on the reaction products, which were identified to be BaAl2O4 and Ba2CaWO6, a reaction was proposed for the barium calcium aluminate material with tungsten. The bottom pellets in the capsules were found to have reacted to a much further extent than the top pellets in all of the samples, possibly due to a temperature gradient or excessive moisture in the base of the capsules. Quantita-tive and semi-quantitative x-ray analysis results did not show a clear trend as to how the concentrations of BaAl2O4 and Ba2CaWO6 vary with time. Most of the barium source materials are hygroscopic, and hydration of the materi-als would substantially reduce the performance of the cathode. Therefore, the environ-mental stability of several barium compounds, 3BaO??2O3 (B3A), 6BaO????2O3 (612), 4BaO????O3 (411), Ba2.9Ca1.1Al2O7 (B4ASSL), and Ba3Sc4O9, were investi-gated in order to evaluate their suitability for use as barium source materials. A micro-balance was used to measure weight gain of the materials as they were exposed to dew points of ??C and 11?t room temperature. The results showed that B3A hydrated more extensively than any of the other materials tested in the low- and intermediate-humidity environments, while the 612, 411, and B4ASSL materials were all reasonably stable in the low-humidity environment. The Ba3Sc4O9 was extremely stable compared to the barium aluminates in the intermediate-humidity conditions. Reservoir hollow cathode Barium source material Tungsten Barium compounds Cathodes Nuclear propulsion
34	High temperature superconducting thin films and quantum interference devices (SQUIDs) for gradiometers Graf zu Eulenburg, Alexander January 1999 (has links) No description available. 530.41
35	Spin coating of passive electroactive ceramic devices Carson, Emma January 2001 (has links) No description available. 621.31042
36	The magnetic properties of superconductors Lloyd, Sion January 1999 (has links) No description available. 530.41
37	A study of structure-property relationships in layered copper oxides Hyatt, Neil January 2000 (has links) No description available. 541
38	Dissociation of hexavalent chromium from primer paint particles into simulated mucus fluid / Moran, Michael Patrick. January 2005 (has links) (PDF) Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).

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