Sökning: "Enriched environment"

Visar resultat 21 - 25 av 93 avhandlingar innehållade orden Enriched environment.

  1. 21. Microbially mediated manganese oxides enriched in yttrium and rare earth elements in the Ytterby mine, Sweden

    Författare :Susanne Sjöberg; Christophe Dupraz; Per Persson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; manganese oxidizers; birnessite; yttrium and rare earth elements YREE ; biofilms; shallow subsurface; Ytterby mine; geomicrobiology; microbial geochemistry; manganoxiderare; birnessit; yttrium och sällsynta jordartsmetaller YREE ; underjordisk; Ytterby mine; geomikrobiologi; mikrobiell kemi; geokemi; Geochemistry;

    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

  3. 22. Environment Related Surface Phenomena and their Influence on Properties of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo : Oxidation at Elevated Temperature and Corrosion During Chemical Treatment

    Författare :Birhan Sefer; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials;

    Sammanfattning : This doctoral thesis covers investigation of the surface phenomena of Ti-6Al-4V and Ti-6Al-2Sn-4Zr-2Mo alloys related with oxidation at elevated temperature and corrosion duringchemical treatment in hydrofluoric-nitric acid (HF/HNO3) solutions. The explored phenomenaare related to manufacturing and service conditions of aero-engine components. LÄS MER

  4. 23. Removing the barriers of plasticity after experimental brain injury

    Författare :Jakob Hakon Christensen; Neurokirurgi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Resting-state functional connectivity; Optical imaging; Stroke; Recovery; Enriched environment; Parvalbumin; Perineuronal nets; Traumatic brain injury; Microglia.;

    Sammanfattning : Ischemic stroke and traumatic brain injuries (TBI) are leading causes of disability and death worldwide. Both injuries result in regional cell death and disruption of local and remote functional neuronal networks, leading to loss of neurological function. LÄS MER

  5. 24. Nanostructure and biomolecule interactions : Characterizing the complex

    Författare :Stefan Gunnarsson; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nanostructures; Proteins; Lipids; Protein corona; Aggregation; Sedimentation; Diffusion; Electron microscopy; Enzyme activity; Nanowires; Nanoparticles;

    Sammanfattning : This thesis presents the results of studies done on various biomolecules and their interactions with nanomaterials. The biomolecule sources are everything from purified, single proteins to the complicated mixture of blood serum and cell culture media. LÄS MER

  7. 25. Diatom and Sedimentological Investigations on West Antarctic Shelf Sediment

    Författare :Charlotte Sjunneskog; Bjorg Stabell; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Antarctica; climate change; diatom abundance; geochemistry; Geovetenskap; Earth sciences; Geovetenskap; Quarternary Geology; kvartärgeologi;

    Sammanfattning : Climate and environmental change following the retreat of the last glacial ice sheet in the Antarctic Peninsula has been interpreted, employing diatom abundance, relative abundance of Chaetoceros resting spores and diatom assemblages as proxies. These together with sedimentological data and radiocarbon dating, suggest four major events that can be further subdivided. LÄS MER