Sökning: "screened interaction"

Visar resultat 1 - 5 av 66 avhandlingar innehållade orden screened interaction.

  1. 1. Role of charge and spin fluctuations and their interplay in solids : A Green’s function approach

    Författare :Tor Sjöstrand; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Green’s function; correlations; collective excitations; screened interaction; electric polarization; orbital and spin magnetization; magnon-phonon interaction; Fierz ambiguity; time-dependent exchange-correlation potential;

    Sammanfattning : Due to the large number of electrons, solid state physics boils down to many-body approximations in which only selected types of collective excitations are taken into account, guided by the emergent properties of the material under study. In this thesis, the collective excitations of primary interest are electronic charge and spin fluctuations(plasmons and magnons) and nuclear charge fluctuations (phonons). LÄS MER

  3. 2. First principles methods for electronic structure calculations of solids

    Författare :Martin Springer; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; screened interaction; T-matrix; vertex function; GW approximation; Green function; density functional theory; gradient expansion; order N method; Physics; Fysik;

    Sammanfattning : A straightforward gradient expansion of the exchange energy of a perturbed electron gas is performed. Studied perturbations range from very weak to those that produce, e.g., a silicon-like band structure with a band gap. LÄS MER

  4. 3. Interfacial Properties of Lipid Liquid Crystalline Nanoparticles

    Författare :Pauline Vandoolaeghe; Fysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; interaction; adsorption; surface; peptide; bilayer; cubic phase; monoolein; cubosome; lipid; liquid crystalline nanoparticles; ellipsometry; neutron reflectivity; QCM-D; SAXD;

    Sammanfattning : Lipid liquid crystalline nanoparticles are studied for their potential as biocompatible carriers for pharmaceutical, food and cosmetic applications. Their potential as delivery vehicles is due to their nanometer size, their controllable structure and physical properties and their large carrying capacity of a wide range of molecules. LÄS MER

  5. 4. Välviljans variationer : Moraliska gränsdragningar inom brottsofferjourer

    Författare :Anna Rypi; Sociologi; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; theory of social work; Social changes; Sociology; Criminology; crises; emotion work; voluntary work; crime victim support; interaction; morality; definition process; Care and help to handicapped; Social psychology; teorier om socialt arbete; Sociala förändringar; Sociologi; Kriminologi; Handikappade; vård och rehabilitering; Socialpsykologi;

    Sammanfattning : Voices from within the victim movement express a need for morality to have fixed boundaries between good and evil, right and wrong. However, such a morality is not always easy to define and uphold. It is thought important to consider the victims particular experiences, through another logic and morality than the strictly legally defined. LÄS MER

  7. 5. Mechanisms of microbial-host interaction during asymptomatic bacteriuria

    Författare :Jenny Grönberg Hernandez; immunologi och glykobiologi - MIG Avdelningen för mikrobiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Asymptomatic bacteriuria; Urinary tract infection; Escherichia coli 83972; IRF3; TLR4; Evolution; host response; promoter polymorphisms; transcription; P fimbriae; Type 1 fimbriae;

    Sammanfattning : Urinary tract infections (UTIs) present an interesting and relevant model for studying microbial adaptation. After establishing significant numbers, the bacteria either cause severe disease, or an asymptomatic carrier state resembling the normal flora at other mucosal sites. LÄS MER