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1. 1. Phase transformation and stability studies of the Zr-H system

   Författare :Tuerdi Maimaitiyili; Lars Hallstadius; Malmö högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zirconium hydride; synchrotron X-ray diffraction; Nuclear materials; phase transformation; in-situ hydrogen charging; hydrogen related degradation; neutron diffraction; powder diffraction; Rietveld analysis; γ-ZrH; hydrogen embrittlement; zirconium hydride; γ-ZrH; synchrotron X-ray diffraction; neutron diffraction; hydrogen charging; in situ phase transformation; hydrogen embrittlement; hydrogen induced degradation;

   Sammanfattning : Zirconium alloys are widely used in the nuclear industry because of their high strength, good corrosion resistance and low neutron absorption cross-section. Zirconium has a strong affinity for hydrogen, however, and if hydrogen concentration builds up, the material will gradually degrade. LÄS MER

3. 2. Structure and Properties Investigations of the La2Co1+z(Ti1-xMgx)1-zO6 Perovskite System

   Författare :Samrand Shafeie; Gunnar Svensson; Mari-Ann Einarsrud; Mats Johnsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; solid oxide fuel cell; SOFC; LaCoO3; cobaltates; cobalt oxide; perovskite; XANES; XRD; Neutron powder diffraction; thermal expansion; electronic conductivity; magnetism; citrate; electron diffraction; synthesis; phase diagram; spin state; fast fas oxid bränslecell; LaCoO3; koboltoxid; perovskit; XANES; XRD; neutron diffraktion; elektron diffraktion; termisk expansion; elektrisk ledningsförmåga; magnetism; citrat; SOFC; syntes; fasdiagram; spin tillstånd; Solid state chemistry; Fasta tillståndets kemi; Materials chemistry; Materialkemi; Structural Chemistry; strukturkemi; Materials Chemistry; materialkemi;

   Sammanfattning : Perovskite based materials have great potentials for various energy applications and the search for new materials for uses in SOFCs has largely been concentrated to this class of compounds. In this search, we have studied perovskite phases in the system La2Co1+z(Ti1-xMgx)1-zO6, with 0  x 0.9 and z = 0.0, 0. LÄS MER

4. 3. Alkali Metal Aurivillius Phases Structure and Electrical Properties

   Författare :Stefan Borg; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; neutron powder diffraction; phase transition; X-ray powder diffraction; Aurivillius phases; impedance spectroscopy; Curie temperature; electron microscopy;

   Sammanfattning : The quest for new materials is crucial for the development of smaller and more efficient electronic components. Aurivillius phases have recently received considerable attention due to their wide-ranging properties and are considered promising candidates in e.g. memory devices, microwave filters and fuel cells. LÄS MER

5. 4. Structure-Magnetic Relationships in the Fe-Mn-P-Si System for Energy Applications

   Författare :Viktor Höglin; Yvonne Andersson; Per Nordblad; Martin Sahlberg; Mogens Christensen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetocaloric; X-ray powder diffraction; Neutron powder diffraction; Magnetization measurements; Phase diagram; Crystal structure; Magnetic structure; Incommensurate structure; Ferromagnetic; Antiferromagnetic; Fe2P; Fe-Mn-P-Si.; Kemi med inriktning mot oorganisk kemi; Chemistry with specialization in Inorganic Chemistry;

   Sammanfattning : Demands for new, energy-efficient appliances have greatly increased in response to our growing need for a more environmentally friendly society. Magnetic refrigeration is a technique that utilizes the magnetocaloric effect, with possible energy savings of up to 30% compared to commercial gas compression refrigerators. LÄS MER

7. 5. Structural and Electrical Transport Properties of Doped Nd-123 Superconductors

   Författare :Shaban Reza Ghorbani; KTH; []
   Nyckelord :high temperature superconductors; critical temperature; resistivity; thermoelectric power; Hall coefficient; X-ray diffraction; Neutron diffraction; NdBa2Cu3O7-delta; hole concentration; substitution;

   Sammanfattning : It is generally believed that one of the key parameterscontrolling the normal state and superconducting properties ofhigh temperature superconductors is the charge carrierconcentrationpin the CuO2planes.By changing the non-isovalent dopingconcentration on the RE site as well as the oxygen content in(RE)Ba2Cu3O7−δ, an excellent tool is obtained tovary the hole concentration over a wide range from theunderdoped up to the overdoped regime. LÄS MER