Sökning: "hydration process"

Visar resultat 16 - 20 av 57 avhandlingar innehållade orden hydration process.

  1. 16. Steel fibrous cement based composites: material and mechanical properties : behavior in the anchorage zones of prestressed bridges

    Författare :Lutfi Ay; KTH; []
    Nyckelord :process improvement of bridges; prestressed concrete; high performance concrete;

    Sammanfattning : This PhD thesis is divided into two parts. Part one dealswith the development of the material and the mechanicalproperties of Steel Fibrous Cement Based Composites (SFCBC) forimproving bridge design and construction. It familiarizes thehydration mechanisms of the high performance concrete with thehelp of Powers´ and Jensen´s models. LÄS MER

  3. 17. Nuclear magnetic resonance studies on bentonite in complex mixed systems

    Författare :Alexander S. Goryan; Willis Forsling; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bentonite; montmorillonite; 23Na; 31P; 29Si NMR; interaction; ion exchange; sorption; Chemistry of Interfaces; Gränsytors kemi;

    Sammanfattning : In this work 23Na MAS NMR was validated as a successful quantitative method for studies of exchanging sodium in bentonites useful, in particular, for studies of ion-exchange kinetics. Na-enriched bentonites equilibrated in a re-circulated process water at iron-oxide pelletizing plants may acquire properties of Ca-bentonites after already 20 minutes of the equilibration time, since >50 % of sodium ions will be exchanged by calcium ions during first minutes of bentonite placed in contact with the process water. LÄS MER

  4. 18. Structure of Hardened Cement-Fly Ash Systems and Their Related Properties

    Författare :Aimin Xu; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; water vapour sorption isotherms; thermogravity analysis; mortar; scanning electron microscopy; differential thermal analysis; X-ray diffraction analysis; fly ash; pore structure; microstructure; cement paste;

    Sammanfattning : The influence of fly ash on the pore structure and microstructure of cement paste and mortar has been investigated. The methods applied include water vapour sorption isotherms, scanning electron microscopy, X-ray diffraction analysis and thermogravity/differential thermal analysis. LÄS MER

  5. 19. Specific ion effects in carboxymethyl cellulose adsorption on cellulose: A step towards modification of fibers in fiber line

    Författare :Vishnu Arumughan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Carboxymethyl cellulose; Polymer adsorption; Cellulose; Specific ionic effects;

    Sammanfattning : The increasing global demands for paper products have fuelled the research in developing new fibers from existing industrial processes. The adsorption of carboxymethyl cellulose (CMC) has been shown to improve the tensile properties of the paper significantly. LÄS MER

  7. 20. Molecular-level controls on water and organics intercalation in layered minerals

    Författare :Jerry Lindholm; Michael Holmboe; Jean-Francois Boily; Virginie Marry; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Minerals; Dynamic Vapor Sorption; montmorillonite; XRD; adsorption model; intercalation;

    Sammanfattning : Layered minerals are naturally abundant and often display a large surface area in relation to their weight. For swelling layered minerals, most of this area is contained between the layers in the interlayer space. LÄS MER