Sökning: "porous silica"

Visar resultat 1 - 5 av 63 avhandlingar innehållade orden porous silica.

  1. 1. Colloidal suspensions of mesostructured silica

    Författare :Andreas Berggren; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; formation mechanism; non-ionic surfactants; silica; inorganic silica; colloidal suspension; control of particle size;

    Sammanfattning : Mesoporous silica is a porous material with walls made of silica and pores in the size range of 2-50 nm. Since the silica most often is amorphous, the material lacks short range order but the pores may be arranged in different structures generating a long-range order. LÄS MER

  3. 2. Functionalization and processing of porous powders into hierarchically porous monoliths

    Författare :Petr Vasiliev; Lennart Bergström; Yoshio Sakka; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Porous; zeolite; hierarchical; monolith; nanoparticle; functionalization; amorphization; PCP; SPS; pulsed current processing; spark plasma sintering.; Chemistry; Kemi; Inorganic Chemistry; oorganisk kemi;

    Sammanfattning : Inorganic porous materials are widely used in a number of applications, where is a need to functionalize and produce materials with a multiscale porosity. The first part of the thesis describes how a novel and facile powder processing approach, using pulsed current processing (PCP) or, as it is commonly called, spark plasma sintering (SPS), has been employed to produce mechanically stable, hierarchically porous bodies from different porous powders. LÄS MER

  4. 3. Aqueous behaviour of characteristic molecules in the synthesis of porous silica materials : - an atomistic description

    Författare :Emelie Nilsson; Fysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; porous silica; struture directing agents; 29Si-NMR; neutron scattering; empirical potentail structure refinement; micelles;

    Sammanfattning : The formation process of porous silica materials is an intricate process, involving a number of components that interact to form a highly organized material. Both zeolites and mesoporous silica materials typically require the presence of organic structure director agents (SDAs) around which the silica network polymerizes. LÄS MER

  5. 4. Preparation and Evaluation of New Nanoporous Silica Materials for Molecular Filtration and for Core Materials in Vacuum Insulation Panels

    Författare :Ebenezer Twumasi Afriyie; Folke Björk; Christer Sjöström; Kjartan Gudmundsson; Per Jostein Hovde; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Adsorbents; activated carbon; MgCa-silica; carbon-silica composite; characterization; porous parameters; molecular filtration; thermal conductivity; thermal insulation;

    Sammanfattning : Nanoporous materials for gas purification and thermal insulation have been studied and developed for application in many areas. It is known that a single adsorbent may not adequately control multiple contaminants. Further the utilization of nanoporous material as thermal insulator in building applications is limited due to high cost. LÄS MER

  7. 5. Microstructure and liquid mass transport control in nanocomposite materials

    Författare :Christoffer Abrahamsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; magnetic alignment; permeability; colloidal gels; microgels; bond water; clay; flow; microstructure; nanocomposites; poly N-isopropylacrylamide ; porous materials; liquid mass transport; diffusion; diffusion NMR; particle aggregation; phase behavior; silica;

    Sammanfattning : Some of the biggest problems currently facing the world are closely tied to unsolved technological challenges in the material sciences. Many materials have a porous microstructure that controls their overall properties. LÄS MER