Search for dissertations about: "Chemical Shrinkage"

Showing result 1 - 5 of 49 swedish dissertations containing the words Chemical Shrinkage.

  2. 1. Modelling of Mass and Heat Transport in Paper - Evaluation of Mechanisms and Shrinkage

    Author : Erik Baggerud; Avdelningen för kemiteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; solid-based coordinates; paper; porous medium; convection; diffusion; volume fractions; mercury displacement; shrinkage; simulations; convective; hot surface; Modelling; drying; Wood; pulp and paper technology; Pappers- och massateknik;

    Abstract : In this work a one-dimensional model for the mass and heat transport in the thickness direction of paper has been developed. Solid-based coordinates were applied to simplify incorporation of shrinkage. Liquid diffusion, gas convection and vapour and air diffusion were incorporated as mass transport mechansims. READ MORE

  4. 2. Variations Related to Print Mottle in Starch-Containing Paper Coatings

    Author : Micael Ragnarsson; Lars Järnström; Gunnar Engström; Martti Toivakka; Karlstads universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pigment coating; porosity variations; coating structure; coat weight variations; starch; dextrin; CMC; latex; print mottle; calendering; pilot coating; offset printing; Chemical Engineering; Kemiteknik;

    Abstract : Starch in paper coatings is known to increase the risk of print mottle in lithographic offset printing. The objective of this study was to increase the understanding of this behaviour. READ MORE

  5. 3. The Effect of Drying Conditions on Paper Curl

    Author : Magnus Persson; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical Engineering; Kemiteknik;

    Abstract : The aim of this study was to further increase the understanding on the mechanisms that influence the development and magnitude of curl after drying. We focused both on the immediate curl measured immediately after drying, and on the process-induced curl measured after conditioning. Both experimental studies and modeling have been conducted. READ MORE

  6. 4. Laboratory method for the study of moisture-induced waviness in paper

    Author : Cecilia Land; Göran Ström; Karlstads universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; method; moisture; paper; paper web; wavelength; waviness; Cellulose and paper engineering; Cellulosa- och pappersteknik; Chemical Engineering; Kemiteknik;

    Abstract : Paper that is subjected to moisture undergoes dimensional changes. It expands during moistening and shrinks during drying. When the paper is under tension between rollers, the effects are complex since shrinkage and expansion are restricted in the width direction. Waves can then appear on the paper web. READ MORE

  7. 5. Phase development, heat of hydration and expansion in a blended cement with b-hemihydrate and anhydrite as calcium sulfate

    Author : Cecilie Evju; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; dilatation; isothermal calorimetry; in-situ synchrotron powder diffraction; ettringite; calcium sulfate; Shrinkage compensating cement; expansive cement; Materiallära; Material technology; materialteknik;

    Abstract : Expansive cements are utilised in special applications to improve properties such as cracking caused by drying shrinkage. Several types of expansive cements exist and the main hydration product responsible for the expansion is ettringite, [Ca3Al(OH)6]2(SO4)3·26H 2O. READ MORE