Sökning: "density gradients"

Visar resultat 1 - 5 av 94 avhandlingar innehållade orden density gradients.

  1. 1. Bipolar electrochemistry for high throughput screening applications

    Författare :Sara Munktell; Fredrik Björefors; Maria Hahlin; Tautgirdas Ruzgas; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; bipolar electrochemistry; electrodeposition; corrosion; screening; gradients; recycling; gold nanoparticles; Scanning Droplet Cell; Hard x-ray photoelectron spectroscopy; pitting corrosion; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

    Sammanfattning : Bipolar electrochemistry is an interesting concept for high throughput screening techniques due to the ability to induce gradients in a range of materials and their properties, such as composition, particle size, or dopant levels, among many others. One of the key advantages of the method is the ability to test, create or modify materials without the need for a direct electrical connection. LÄS MER

  2. 2. New Approaches to Large-Scale Electronic Structure Calculations

    Författare :Francesco Aquilante; Teoretisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Theoretical chemistry; orbital localization; electron correlation; analytic gradients; Cholesky decomposition; density fitting; quantum chemistry; Teoretisk kemi; kvantkemi;

    Sammanfattning : Recent years have witnessed a growing interest of the scientific community for the use of ab initio and density functional theory methods in theoretical studies of molecules containing many atoms. However, the `scaling wall' of some of the most accurate of such methods is often an obstacle for their applicability to systems of real-life interest, e. LÄS MER

  3. 3. Freshwater, density gradients and biological processes in cold, brackish seas : aspects of the biogeophysical fluid dynamics characterising the Baltic Sea

    Författare :Tapani Stipa; Peter Haugan; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Östersjön; Oceanografi; meteorologi; Meteorology;

    Sammanfattning : The dominant component in the ocean water is freshwater. In this thesis its mixing and the freshwater-induced dynamics are discussed, with cold, brackish basins such as the Baltic Sea especially in mind. A mathematical framework is derived to allow for a consistent way of adding freshwater effects to the governing equations. LÄS MER

  4. 4. Extending the Reach of Accurate Wavefunction Methods

    Författare :Mickaël G. Delcey; Roland Lindh; Per-Åke Malmqvist; Martin Schütz; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; Density fitting; CASSCF; Analytical gradients; Photochemistry; X-ray spectroscopy; Kemi med inriktning mot kvantkemi; Chemistry with specialization in Quantum Chemistry;

    Sammanfattning : Multiconfigurational quantum chemistry methods, and especially the multiconfigurational self-consistent field (MCSCF) and multireference perturbation theory (MRPT2), are powerful tools, particularly suited to the accurate modeling of photochemical processes and transition metal catalysis. However, they are limited by their high computational cost compared to other methods, especially density functional theory. LÄS MER

  5. 5. Waves and instabilities in quantum plasmas

    Författare :Shahid Ali; Padma Kant Shukla; Mattias Marklund; Jose Tito Mendonca; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Quantum mechanical effects; dusty plasma; linear and nonlinear waves; instabilities; nonlinear wave interactions; density gradients; magnetoplasmas.; Plasma physics; Plasmafysik;

    Sammanfattning : The study of waves and instabilities in quantum plasmas is of fundamental importance for understanding collective interactions in superdense astrophysical objects, in high intense laser-plasma/solid-matter interactions, in microelectronic devices and metallic nanostructures. In dense quantum plasmas, there are new pressure laws associated with the Fermi-Dirac distribution functions and new quantum forces associated with the quantum Bohm potential and the Bohr magnetization involving electron ½ spin. LÄS MER