Sökning: "dispersion forces"

Visar resultat 21 - 25 av 51 avhandlingar innehållade orden dispersion forces.

  1. 21. Theory of van der Waals bonding: from bulk materials to biomolecules

    Författare :Elisa Londero; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; alkanes; extended systems; DNA; band structure; van der Waals Density Functional vdW-DF ; exchange functionals; Density Functional Theory; non-local correlation; layered oxides;

    Sammanfattning : Sparse matter is abundant in Nature.It encompasses systems characterized by an intrinsic low density of electrons in sizeable regions, where the van der Waals forces contribute considerably to cohesion.Given the length scale of the problem, a prediction of these materials requires appropriate tools within a quantum-mechanical framework. LÄS MER

  3. 22. Asymmetric transfer hydrogenation of aromatic ketones and azirines with NH-ligands

    Författare :Peter Roth; Krister Zetterberg; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : The Ru(arene)[(1S, 3R, 4R)-3-(Hydroxymethyl)-2-azabicyclo[2.2.1]heptane catalyst was optimized as ligand in the asymmetric transfer hydrogenation of ketones and resulted in increased activity and enantioselectivity of the catalyst. LÄS MER

  4. 23. Cellulose nanofibril materials with controlled structure : the influence of colloidal interactions

    Författare :Andreas Fall; Lars Wågberg; Anna Finne Wistrand; Paul Gatenholm; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Colloidal stability; cellulose nanofibrils; nanofibers; nanostructured materials; biocomposite; DLVO; gel;

    Sammanfattning : Nanoparticles are very interesting components. Due to their very large specific surface area they possess properties in between molecules and macroscopic materials. In addition, a material built up of hierarchically assembled nanoparticles could obtain unique properties, not possessed by the nanoparticles themself. LÄS MER

  5. 24. Numerical modeling of air-fiber flows

    Författare :Jelena Andric; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aggregation; particle-level simulation; rheology; fiber; dry-forming; fiber suspension;

    Sammanfattning : The dynamics of fiber suspensions are of great importance in applications such as the dry-forming process of pulp mats for use in hygiene products. In this forming process, fibers are transported in flowing air. The fibers interact with the fluid, and may interact with each other and interlock in flocs. LÄS MER

  7. 25. Dynamic higher order equations

    Författare :Hossein Abadikhah; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Torsion; Series expansion; Elasticity; Micropolar; Functionally graded material;

    Sammanfattning : The subject of this thesis is to derive and evaluate governing equations and correspondingboundary conditions for solid cylinders and rectangular plates, where the materialconstituting the cylinder or plate are governed by classical elasticity, micropolar elasticityor a functionally graded case of the previously mentioned models. This is achieved by asystematic power series expansion approach, by either adopting a generalized Hamilton'sprinciple or a direct approach. LÄS MER