Search for dissertations about: "Rare earth elements"

Showing result 1 - 5 of 50 swedish dissertations containing the words Rare earth elements.

  1. 1. Agpaitic Rocks of the Norra Kärr Alkaline Complex: Chemistry, Origin, and Age of Eudialyte-hosted Zirconium and Rare-earth Element Ore

    University dissertation from Göteborg : University of Gothenburg

    Author : Axel S.L. Sjöqvist; Göteborgs universitet.; Gothenburg University.; [2015]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Norra Kärr alkaline complex; agpaitic rocks; eudialyte; rare-earth elements; geochronology; radiogenic isotope geochemistry;

    Abstract : 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. READ MORE

  2. 2. Robust Multi-objective Optimization of Rare Earth Element Chromatography

    University dissertation from Chemical Engineering, Lund University

    Author : Hans-Kristian Knutson; Lunds universitet.; Lund University.; [2016-06-03]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chromatography; Rare earth elements; Modeling; Multi-objective optimization; Robust optimization; Chromatography; Rare earth elements; Modeling; Multi-objective optimization; Robust optimization;

    Abstract : Rare earth elements comprise the metallic elements known as lanthanides as well as scandium and yttrium. They are extensively used in modern technological industries and are considered as strategic commodities in many countries. READ MORE

  3. 3. Hydrometallurgical recovery of rare earth elements from flourescent lamp waste fractions

    University dissertation from Chalmers University of Technology

    Author : Cristian Tunsu; Chalmers tekniska högskola.; Chalmers University of Technology.; [2016]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fluorescent lamp waste; rare earth elements; recycling; waste treatment; leaching; solvent extraction; Cyanex 923; Cyanex 572;

    Abstract : Recovery and reuse of materials is important for a circular economy. In recent years the recovery of critical metals from end-of-life products has received increased attention. Various streams, e.g. READ MORE

  4. 4. Radiative Properties of Rare Earth Elements - Free and Bound in Crystals

    University dissertation from Chalmers University of Technology

    Author : Huailiang Xu; Lunds universitet.; Lund University.; [2004]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Laser Spectroscopy; Upconversion; Lifetimes; Atomic and molecular physics; Atom- och molekylärfysik; Laser technology; Laserteknik; Rare earth Elements; Fysicumarkivet A:2004:Xu;

    Abstract : This thesis is devoted to fundamental aspects, and to spectroscopic applications of radiative properties in free atoms and ions, as well as in ions doped into crystals. Using the time-resolved laser-induced fluorescence technique, measurements of radiative lifetimes for rare earth elements have been performed in neutral Pr, Nd, Tm, and in singly ionized Sm, Er, Nd, Tm, Yb, as well as in doubly ionized Tm and Tb ions. READ MORE

  5. 5. Microbially mediated formation of birnessite-type manganese oxides and subsequent incorporation of rare earth elements, Ytterby mine, Sweden

    University dissertation from Stockholm : Department of Geological Sciences, Stockholm University

    Author : Susanne Sjöberg; Stockholms universitet.; [2017]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; microbial diversity; manganese oxides; birnessite; rare earth elements; subterranean; Ytterby mine; geokemi; Geochemistry;

    Abstract : 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. READ MORE