Search for dissertations about: "NATURAL SCIENCES Physics Condensed matter physics Defects and diffusion"

Showing result 1 - 5 of 20 swedish dissertations containing the words NATURAL SCIENCES Physics Condensed matter physics Defects and diffusion.

  2. 1. Simulation of relaxation processes in complex condensed matter systems : Algorithmic and physical aspets

    Author : Tomas Oppelstrup; Mikhail Dzugutov; Göran Wahnström; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Condensed matter physics; Kondenserade materiens fysik; Numerical analysis; Numerisk analys; Materials science; Teknisk materialvetenskap; Defects and diffusion; Defekter och diffusion;

    Abstract : This thesis summarizes interrelated simulation studies of three different physical phenomena. The three topics are: simulation of work hardening of materials using dislocation dynamics, investigation of anomalous diffusion in supercooled liquids using molecular dynamics,and kinetic Monte-Carlo simulation of annealing of radiation damaged materials. READ MORE

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

    Author : Andreas Blomqvist; Rajeev Ahuja; Christopher Wolverton; Uppsala universitet; []
    Keywords : 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;

    Abstract : 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. READ MORE

  5. 3. Novel Layered and 2D Materials for Functionality Enhancement of Contacts and Gas Sensors

    Author : Hossein Fashandi; Per Eklund; Anita Lloyd Spetz; Mike Andersson; Lars Hultman; Ganpati Ramanath; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Chemical gas sensors are widely-used electronic devices for detecting or measuring the density levels of desired gas species. In this study, materials with established or potential applications for gas sensors are treated. READ MORE

  6. 4. Influence of defects and impurities on the properties of 2D materials

    Author : Soumyajyoti Haldar; Biplab Sanyal; Olle Eriksson; Torbjörn Björkman; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 2D Materials; Defects on 2D materials; Impurities on 2D materials; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Abstract : Graphene, the thinnest material with a stable 2D structure, is a potential alternative for silicon-based electronics. However, zero band gap of graphene causes a poor on-off ratio of current thus making it unsuitable for logic operations. This problem prompted scientists to find other suitable 2D materials. READ MORE

  7. 5. Multiscale modeling of atomic transport phenomena in ferritic steels

    Author : Luca Messina; Pär Olsson; Nils Sandberg; Pål Efsing; Pascal Bellon; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; diffusion; impurities; iron; metals; kinetic Monte Carlo; ab initio; mean field; defects; embrittlement; reactor pressure vessel; neural networks; Fysik; Physics;

    Abstract : Defect-driven transport of impurities plays a key role in the microstructure evolution of alloys, and has a great impact on the mechanical properties at the macroscopic scale. This phenomenon is greatly enhanced in irradiated materials because of the large amount of radiation-induced crystal defects (vacancies and interstitials). READ MORE