Sökning: "rare earths"

Visar resultat 11 - 15 av 17 avhandlingar innehållade orden rare earths.

1. 11. Isotope enrichment by countercurrent electromigration in molten salts

   Författare :Arnold Lundén; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : A series of isotope enrichments by electromigration in molten saltslias been carried out during the last, years. The running conditions aresummarized in table 1 and the enrichments achieved are given intables 2—13. Practical details such as the arrangement of the electricalcircuits and the construction of the separation columns are discussed. LÄS MER

3. 12. The flux of extraterrestrial spinels to Earth associated with He-3 anomalies in Cenozoic and Ordovician sediments

   Författare :Samuele Boschi; Kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Chromite; He-3 anomaly; Cenozoic; mid-Ordovician; asteroid breakup; ordinary chondrites; Popigai ejecta; iridium anomaly; Zircons; ice age;

   Sammanfattning : The main goal of this thesis is to reconstruct the flux of extraterrestrial matter to Earth in specific time intervals of our past in order to add an astronomical dimension to the understanding of Earth's history. To accomplish this, extraterrestrial chrome-spinel grains have been extracted and analysed. LÄS MER

4. 13. Electronic Structure and Atomistic Spin Dynamics of Nanostructured Materials

   Författare :Debora C. M. Rodrigues; Anders Bergman; Manuel Pereiro; Olle Eriksson; Helena Petrilli; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : The theoretical studies of several magnetic materials are presented in this thesis. To each of them, it was investigated the electronic structure, by means of density functional theory calculations, and/or magnetization dynamics, in the context of atomistic spin dynamics (ASD). LÄS MER

5. 14. U-Pb dating of detrital zircon from the Mt. Alfred area, Yilgarn Craton, Western Australia

   Författare :Ross Kielman; Martin Whitehouse; Alexander Nemchin; Victoria Pease; Åke Johansson; Jenny Andersson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Detrital zircon; Geochronology; Archean; Hadean; Western Australia; Geology; geologi;

   Sammanfattning : Hadean and Paleo-Eoarchean aged detrital zircon provide a rare glimpse into the nature of the early Earth. Thus, the characterisation of new localities with rocks that host Hadean and Paleo-Eoarchean zircon provide invaluable insight into the Earth’s early crust. LÄS MER

7. 15. Synthesis, Surface Modification, and Characterization of Metal Oxide Nanoparticles : Nanoprobes for Signal Enhancement in Biomedical Imaging

   Författare :Linnéa Selegård; Kajsa Uvdal; Pentti Tengvall; Linköpings universitet; []
   Nyckelord :;

   Sammanfattning : In this thesis we investigate crystalline metal oxide nanoparticles of our own design to obtain nanoprobes for signal enhancement and bioimaging purposes. We report fabrication, surface modification and characterization of nanoparticles based on zinc (Zn), and rare earths (i.e. gadolinium (Gd) and europium (Eu)) singly and in combination. LÄS MER