Sökning: "diffusion"

Visar resultat 1 - 5 av 1838 avhandlingar innehållade ordet diffusion.

  1. 1. Diffusion in Bone Tissue

    Författare :Gustav Lindberg; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bone growth; diffusion; stress enhanced; finite element method; steady-state; periosteal membrane; diffusion in bovine bone; diffusion experiment; Conductivity measurement; Fick’s law; Fourier series; Kalman filter; transient solution;

    Sammanfattning : In order to prevent or modify the processes of bone degeneration the modeling and remodeling of bone tissue must be better understood. In this thesis it is assumed that the primary condition leading to bone growth is a change of the chemical environment caused by transport of matter resulting from stress driven diffusion. LÄS MER

  2. 2. Insights into Materials Properties from Ab Initio Theory : Diffusion, Adsorption, Catalysis & Structure

    Författare :Andreas Blomqvist; Rajeev Ahuja; Christopher Wolverton; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Molecular dynamics; Diffusion; Catalysis; Adsorption; Random structure search; Hydrogen-storage materials; Phase-change materials; Defects and diffusion; Defekter och diffusion; Surfaces and interfaces; Ytor och mellanytor; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, density functional theory (DFT) calculations and DFT based ab initio molecular dynamics simulations have been employed in order to gain insights into materials properties like diffusion, adsorption, catalysis, and structure. In transition metals, absorbed hydrogen atoms self-trap due to localization of metal d-electrons. LÄS MER

  3. 3. Pushing diffusion MRI towards new dimensions

    Författare :Joao Martins; Fysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NMR; MRI; diffusion; relaxation; multidimensional diffusion MRI; relaxation-diffusion correlations; Laplace NMR; porous media; tissue microstructure; heterogeneity; anisotropy;

    Sammanfattning : Diffusion-MRI techniques allow the non-invasive investigation of microstructural changes in living tissues. However, a detailed interpretation of the data is complicated by the fact that multiple microscopic environments with varying diffusion properties all contribute to the measured signal. LÄS MER

  4. 4. Diffusion of Radionuclides in Bentonite Clay : Laboratory and in sity Studies

    Författare :Mats Jansson; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Bentonite; montmorillonite; cation; anion; diffusion; sorption; cobalt; caesium; strontium; iodide; pertechnetate; surface diffusion; in situ; Chemistry; Kemi;

    Sammanfattning : This thesis deals with the diffusion of ions in compactedbentonite clay. Laboratory experiments were performed toexamine in detail different processes that affect thediffusion. To demonstrate that the results obtained from thelaboratory investigations are valid under in situ conditions,two different kinds of in situ experiments were performed. LÄS MER

  5. 5. Diffusion of dynamic innovations : A case study of residential solar PV systems

    Författare :Emrah Karakaya; Cali Nuur; Antonio Hidalgo; Anna Bergek; KTH; []
    Nyckelord :SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; Dynamic innovations; diffusion; residential solar; photovoltaics; time; space; Industriell ekonomi och organisation; Industrial Engineering and Management;

    Sammanfattning : In the literature on diffusion of innovations, it is widely known that the characteristics and socio-environmental settings of adopters do evolve in space and time. What about innovations themselves? During the diffusion process, don’t some innovations continuously alter in space and time? If so, how does the dynamic character of an innovation influence the diffusion process? In previous research, it has been often assumed that innovations do not continuously alter or get modified when diffusing from a source to potential adopters. LÄS MER