Sökning: "RARE-EARTH ELEMENTS"
Visar resultat 11 - 15 av 67 avhandlingar innehållade orden RARE-EARTH ELEMENTS.
11. Agpaitic Rocks of the Norra Kärr Alkaline Complex: Chemistry, Origin, and Age of Eudialyte-hosted Zirconium and Rare-earth Element Ore
Sammanfattning : Agpaites are peralkaline nepheline syenites that are denominated by rock-forming complex silicate minerals such as eudialyte. The exotic mineralogy and chemistry of these rocks are not only interesting for research, but globally these rocks also have potential as polymetallic resources of elements such as zirconium, niobium, rare-earth elements, zinc, and uranium. LÄS MER
12. Light-Matter Interaction and Quantum Computing in Rare-Earth-Ion-Doped Crystals
Sammanfattning : In this thesis, crystals of yttrium orthosilicate (Y2SiO5) that are randomly doped with another rare-earth element, such as praseodymium (Pr), europium (Eu), or cerium (Ce), are investigated with lasers locked to ultra-stable cavities using the Pound-Drever-Hall locking technique. Many of these rare-earth elements have long-lived 4f-4f transitions, hundreds of microseconds to a few milliseconds, with even longer ground hyperfine lifetimes of up to several days. LÄS MER
13. Microbially mediated manganese oxides enriched in yttrium and rare earth elements in the Ytterby mine, Sweden
Sammanfattning : Microorganisms are able to manipulate redox reactions and thus exert extensive control on chemical speciation and element partitioning in nature, affecting the formation and dissolution of certain minerals. One of these redox active elements is manganese (Mn), which in its oxidized states (III/IV), commonly forms Mn oxide-hydroxide minerals. LÄS MER
14. Origin and mobility of major and key trace elements (Cs, YREEs) in fracture groundwater in the upper 1.2 kilometres of coastal granitoids : Implications for future repositories of spent nuclear fuel
Sammanfattning : This thesis focuses on the chemical and isotopic features of groundwater residing in the upper 1.2 km of sparsely fractured crystalline bedrock of the Baltic Shield. LÄS MER
15. Structure-Magnetism Relations in Selected Iron-based Alloys : A New Base for Rare Earth Free Magnetic Materials
Sammanfattning : Materials for energy applications are of great importance for a sustainable future society. Among these, stronger, lighter and more efficient magnetic materials will be able to aid mankind in many applications for energy conversion, for example generators for energy production, electric vehicles and magnetic refrigerators. LÄS MER