Sökning: "Rare earth elements"
Visar resultat 1 - 5 av 67 avhandlingar innehållade orden Rare earth elements.
1. Microbially mediated formation of birnessite-type manganese oxides and subsequent incorporation of rare earth elements, Ytterby mine, Sweden
Sammanfattning : Microbes exert extensive control on redox element cycles. They participate directly orindirectly in the concentration and fractionation of elements by influencing the partitioningbetween soluble and insoluble species. LÄS MER
Sammanfattning : Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. LÄS MER
3. Abundance and fractionation of rare earth elements in calcite and other secondary minerals in fractures in the upper kilometre of crystalline bedrock, SE Sweden
Sammanfattning : This thesis focuses on the geochemistry of secondary minerals, mainly calcite but also others such as fluorite and Ca/Al silicates, precipitated throughout the last 1.5 billion years in fractures of crystalline rock, SE Sweden. LÄS MER
4. 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
5. 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