Sökning: "Kemisk bindning"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden Kemisk bindning.

  1. 1. Interfacial properties of calcium montmorillonite in aqueous solutions : Density functional theory and classical molecular dynamics studies on the electric double layer

    Författare :Guomin Yang; Göran Lindbergh; Ivars Neretnieks; Michael Holmboe; Jan Forsman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Clay minerals; Bentonite; density functional theory; molecular dynamics; GROMACS; electric double layer; electrolytes; ionic liquids; primitive model; CLAYFF forcefield.; Chemical Engineering; Kemiteknik;

    Sammanfattning : The swelling properties of Bentonite are highly affected by clay content and the clay-water interactions that arise from the ion distribution in the diffuse double layer formed near the charged montmorillonite (or smectite) surfaces. Existing continuum models describing the electric double layers, such as classical Poisson-Boltzmann and DLVO theory, ignore the ion-ion correlations, which are especially important for multivalent ions at high surface charge and ionic strength. LÄS MER

  3. 2. Computational-chemistry studies of hydrogen bonding networks in crystalline materials and liquid water

    Författare :Tomas Hirsch; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemisk bindning;

    Sammanfattning : .... LÄS MER

  4. 3. Drama i kemisalen : En designbaserad studie av hur kreativt drama kan stödja gymnasieelevers lärande av kemisk bindning

    Författare :Kerstin Danckwardt-Lillieström; Maria Andrée; Margareta Enghag; Marianne Ødegaard; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; naturvetenskapsämnenas didaktik; Science Education;

    Sammanfattning : A major challenge for chemistry education is to develop the students' understanding of chemical bonding. In upper-secondary school, the challenges are commonly expressed as difficulties for students to distinguish between intra and intermolecular bonding and to understand chemical bonding in terms of electronegativity. LÄS MER

  5. 4. Femtosecond Dynamics and Photochemistry in Solution

    Författare :Marcus Rasmusson; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry; cross-correlation function; chloroiodomethane; dihalides; bromobenzene; ion pairs; solvation; vibrational relaxation; charge-transfer; tetranitromethane; electron transfer; femtosecond spectroscopy; dissociation; Photochemistry; Fotokemi; Chemical technology and engineering; Kemiteknik och kemisk teknologi;

    Sammanfattning : The reaction dynamics of several polyatomic systems have been investigated in solution by femtosecond spectroscopy. Tetranitromethane-naphtalene complexes excited in the charge-transfer band at 400 nm undergo dissociative electron transfer, resulting in three primary products: [naphthalene].+, NO2 and C(NO2)3-. LÄS MER

  7. 5. Modeling of Hindered Diffusion in Gels

    Författare :Jan Gutenwik; Avdelningen för kemiteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; effective diffusion coefficient; pore size distribution; obstruction; immobilization; modeling; adsorption kinetics; hindered diffusion; simulation program; proteins; Chemical technology and engineering; Kemiteknik och kemisk teknologi;

    Sammanfattning : Hindered diffusion occurs in the most different processes, as has been described in this thesis. It is very important to have an understanding of the influence of hindered diffusion on the mass transfer rate, especially when competing rate processes are acting simultaneously. LÄS MER