Sökning: "non-collinearity"

Hittade 3 avhandlingar innehållade ordet non-collinearity.

  1. 1. Novel computational methods for image analysis and quantification using position sensitive radiation detectors

    Författare :Alejandro Sanchez Crespo; Stig A. Larsson; Magnus Dahlbom; Stockholms universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; SPET; PET; CMOS; spatial resolution; photon depth of interaction; positron annihilation; positron range; non-collinearity; scatter; attenuation; lung ventilation; lung perfusion; breast tumour; Medicine; Medicin;

    Sammanfattning : The major advantage of position sensitive radiation detector systems lies in their ability to non invasively map the regional distribution of the emitted radiation in real-time. Three of such detector systems were studied in this thesis, gamma-cameras, positron cameras and CMOS image sensors. LÄS MER

  3. 2. The Structural Basis for Magnetic Order in New Manganese Compounds

    Författare :Therese Eriksson; Yvonne Andersson; Helmer Fjellvåg; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; Crystal structure; Magnetic structure; Manganese compounds; Transition metal silicides; Transition metal germanides; Magnetic frustration; Neutron powder diffraction; X-ray diffraction; Magnetisation measurements; DFT; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi;

    Sammanfattning : Materials with new or improved properties are crucial for technological development. To provide the foundation for future successful products, it is important to prepare and characterise new chemical compounds that could show unusual properties. LÄS MER

  4. 3. Electronic structure and exchange interactions from ab initio theory : New perspectives and implementations

    Författare :Ramon Cardias Alves de Almeida; Olle Eriksson; Anders Bergman; Attila Szilva; R. B. Muniz; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio; exchange interactions; non-collinear magnetism; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, the magnetic properties of several materials were investigated using first principle calculations. The ab initio method named real space linear muffin-tin orbitals atomic sphere approximation (RS-LMTO-ASA) was used to calculate the electronic structure and magnetic properties of bulk systems, surface and nanostructures adsorbed on surfaces. LÄS MER