Sökning: "Mats Boman"

Visar resultat 6 - 10 av 17 avhandlingar innehållade orden Mats Boman.

  1. 6. On the Attachment of Lightning Flashes to Grounded Structures

    Författare :Marley Becerra; Vernon Cooray; Rajeev Thottappillil; Mats Boman; Ivo Gallimberti; Uppsala universitet; []
    Nyckelord :Engineering physics; Lightning; Lightning attachment; Positive leader discharges; Lightning protection; Thunderstorms; Numerical modeling; Teknisk fysik;

    Sammanfattning : This thesis deals with the physical modeling of the initiation and propagation of upward positive leader discharges from grounded structures during lightning strikes. It includes the analysis of upward leaders initiated under the influence of the electric field produced by a dominant negative cloud charge and due to the combined action of a negative thundercloud and a descending downward stepped negative leader. LÄS MER

  3. 7. Chemical vapor deposition of hard coatings : Development of W(C,N) coatings for cemented carbide and TiN deposition on a CoCrFeNi substrate

    Författare :Katalin Böőr; Mats Boman; Markku Leskelä; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : There is a constant need for cutting tool material development to be able to machine new materials and improve the metal cutting efficiency. Inserts of indexable cutting tools usually consist of WC-Co cemented carbide (cc) with μm thick layers of ceramic coatings. LÄS MER

  4. 8. Synthesis and Characterisation of Ultra Thin Film Oxides for Energy Applications

    Författare :Mattis Fondell; Mats Boman; Tomas Edvinsson; Andreas Lindblad; Christophe Detavernier; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Atomic Layer Deposition; Iron oxides; Hematite; Solar Water Splitting; Hard X-Ray Photoelectron Spectroscopy;

    Sammanfattning : This thesis describes studies of materials which can be exploited for hydrogen production from water and sunlight. The materials investigated are maghemite (γ-Fe2O3), magnetite (Fe3O4) and especially hematite (α-Fe2O3), which is an iron oxide with most promising properties in this field. LÄS MER

  5. 9. Muspel and Surtr : CVD system and control program for WF6 chemistry

    Författare :Johan Gerdin Hulkko; Mats Boman; Tobias Törndahl; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CVD; W; WN; system; WF6; TiN; control program; LabView; CVD; W; WN; system; WF6; TiN; styrprogram; LabView; Chemistry with specialization in Inorganic Chemistry; Kemi med inriktning mot oorganisk kemi;

    Sammanfattning : CVD (Chemical Vapour Deposition) is an advanced technique for depositing a coating on a substrate. CVD implies that a solid phase is deposited on a normally heated substrate surface using a reactive, gaseous mixture. The reaction gas mixture must be carefully chosen to prevent homogeneous nucleation in the gas phase. LÄS MER

  7. 10. Template-Based fabrication of Nanostructured Materials

    Författare :Anders Johansson; Mats Boman; Kornelius Nielsch; Uppsala universitet; []
    Nyckelord :Inorganic chemistry; Nanoparticles; nanotubes; anodic aluminium oxide; electroless deposition; ALD; Nb2O5; Prussian blue; palladium; copper; ion beam lithography; TiO2; SiO2; Oorganisk kemi;

    Sammanfattning : Materials prepared on the nanoscale often exhibit many different properties compared to the same materials in their bulk-state. Interest in nanostructured materials has increased because of these properties in fields such as microelectronics, catalysis, optics and sensors. LÄS MER