Sökning: "nitrogen iron"

Visar resultat 16 - 20 av 78 avhandlingar innehållade orden nitrogen iron.

  1. 16. Characteristics and Sintering of Fine Water-atomized and Carbonyl Iron Powder

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Johan Wendel; [2018]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sintering; powder metallurgy; iron powder; dilatometry; surface analysis; thermal analysis;

    Sammanfattning : Various types of iron powder are extensively used in the powder metallurgy (PM) industry. Water-atomized iron powder is commonly used as the base in many low-alloyed steel products manufactured through the conventional 'press and sinter' route, while carbonyl iron powder is often used for metal injection moulded (MIM) components. LÄS MER

  2. 17. Factors Influencing the Formation of Shrinkage Porosity in Grey Cast Iron

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Lennart Elmquist; [2008]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CET; Oxygen; Columnar zone; Grey iron; Shrinkage porosity; Equiaxed zone; Solidification; DAAS; Hydrogen; Primary austenite;

    Sammanfattning : The presence of shrinkage defects is of major concern in the production of grey iron castings. This type of defect can penetrate through the casting as a three-dimensional network. LÄS MER

  3. 18. Crystallization on the Mesoscale Self-Assembly of Iron Oxide Nanocubes into Mesocrystals

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Michael Agthe; Lennart Bergström; German Salazar-Alvarez; Tommy Nylander; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Self-assembly; iron oxide nanocubes; mesocrystal; small angle X-ray scattering; video microscopy; QCM-D; materialkemi; Materials Chemistry;

    Sammanfattning : Self-assembly of nanoparticles is a promising route to form complex, nanostructured materials with functional properties. Nanoparticle assemblies characterized by a crystallographic alignment of the nanoparticles on the atomic scale, i.e. mesocrystals, are commonly found in nature with outstanding functional and mechanical properties. LÄS MER

  4. 19. Brownification of freshwaters - the role of dissolved organic matter and iron

    Detta är en avhandling från Department of Biology, Lund University

    Författare :Sara Ekström; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Brownification; freshwater; water color; dissolved organic matter DOM ; iron Fe ; decreasing acidification; climate change;

    Sammanfattning : The term brownification refers to the trend of increasing water color, i.e. the water becoming browner, which has been observed throughout the northern hemisphere over the last decades. Brownification has both ecological and societal implications. LÄS MER

  5. 20. Iron-nitrogen containing carbon catalysts for oxygen reduction in fuel cells

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Caroline Janson; [2018]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; active site; mesoporous carbon; fuel cell; electron paramagnetic resonance; oxygen reduction reaction; cathode catalyst; non-precious metal catalyst;

    Sammanfattning : New solutions to efficiently convert energy are needed to mitigate global climate changes and sustain the needs of the growing population. An energy device with high potential is the proton exchange membrane (PEM) fuel cell. PEM fuel cells can convert chemical energy to electrical energy with extraordinary high conversion efficiency. LÄS MER