Sökning: "size-dependence"

Visar resultat 6 - 10 av 30 avhandlingar innehållade ordet size-dependence.

  1. 6. Resonance-enhanced Second Harmonic Generation from spherical microparticles in aqueous suspension

    Författare :Sviatlana Viarbitskaya; Tony Hansson; Micha Bonn; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; second harmonic generation; adsorption; molecules; Physics; Fysik; Physics; fysik;

    Sammanfattning : Second harmonic generation (SHG) is a nonlinear optical effect sensitive to interfaces between materials with inversion symmetry. It is used as an effective tool for detection of the adsorption of a substance to microscopic particles, cells, liposomes, emulsions and similar structures, surface analysis and characterization of microparticles. LÄS MER

  3. 7. Reactivity of Metal Clusters with Diatomic Molecules

    Författare :Lotta Holmgren; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nbn; cluster; reactivity; Rhn; NO; D2; CO; N2; laser vaporization; Wn; Nin; photoionization; time-of-flight mass spectrometer; ionization potential; Cun; O2; Vn;

    Sammanfattning : The reactivity of transition-metal clusters, in the approximate size range 10-60 atoms, with diatomic molecules has been investigated. A pulsed beam of neutral clusters is produced by a laser-vaporization source and passed through a low-pressure reaction cell containing the reactive gas. LÄS MER

  4. 8. Metal Cluster Reactivity. Adsorption of small molecules in biomolecular collisions

    Författare :Mats Andersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; O2; CO; ionization potential; Con; Fen; NO; sticking probability; laser ionization; D2; Wn; Cun; Rhn; reaction probability; cluster; jellium model; Nbn; metal cluster reactivity; N2; time-of-flight mass spectrometry; Nin;

    Sammanfattning : Metal clusters can be characterized as the tiniest possible metal particles, containing only an easily counted number of atoms. In this work, reactions between metal clusters and diatomic molecules have been investigated. We have constructed an experimental set-up to produce and detect clusters, and to investigate their chemical reactivity. LÄS MER

  5. 9. Methods to Generate Size- and Composition Controlled Aerosol Nanoparticles

    Författare :Martin Karlsson; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; differential mobility analyzer DMA ; transfer function; binary alloy nanoparticles; nanoparticle generator; thermal decomposition; Physics; sintering; Fysik; size selection; nanoparticles; aerosol technology; Fysicumarkivet A:2004:Karlsson;

    Sammanfattning : This thesis describes experiments performed using different methods to produce aerosol nanoparticles with control over size and composition. The process included differential mobility analyzers (DMAs) as size-selecting instruments and tube furnaces for particle synthesis. LÄS MER

  7. 10. Thermal and Photon Stimulated Reactions on Metal Particles

    Författare :Kristina Wettergren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Plasmons; Platinum Clusters; Platinum Nanoparticles; Hydrogen Oxidation; Sodium; Silver Nanoparticles; Nitric Oxide; Photodesorption; Sintering; Graphite; Water;

    Sammanfattning : The interaction between molecules and solid surfaces influence our daily lives in many ways. One important example is heterogeneous catalysis where surface reactions, for example, are used for production of chemicals and exhaust after-treatment. LÄS MER