Search for dissertations about: "wood fibres"

Showing result 1 - 5 of 107 swedish dissertations containing the words wood fibres.

  1. 1. Strength grading of structural timber and EWP laminations of Norway spruce : Development potentials

    Author : Jan Oscarsson; Anders Olsson; Marie Johansson; Mikael Perstorper; SP Sveriges Tekniska Forskningsinstitut; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; bending strength; fibre angle; grain angle; knots; laser scanning; machine strength grading; modulus of elasticity; strain measurement; structural timber; tensile strength; wood; böjhållfasthet; draghållfasthet; elasticitetsmodul; fibervinkel; konstruktionsvirke; kvistar; laserskanning; maskinell hållfasthetssortering; trä; töjningsmätning; Byggteknik; Civil engineering;

    Abstract : Strength grading of structural timber is a process by which value is added to sawn products. It is to the greater part carried out using machine grading based on statistical relationships between so called indicating properties and bending strength. READ MORE

  2. 2. Fluid dynamics and flow structures of wood fibres suspended in gas flows

    Author : Olof Melander; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; two-fluid model; fibres; flocculation; multiphase flow; flow regimes; particle transport; fibre suspensions; Particle Image Velocimetry; Computational Fluid Dynamics; lift force; concentration measurement;

    Abstract : The flow of wood fibres suspended in gas plays a major role in the MDF (Medium Density Fibreboard) production process. Development of machinery in this industry has traditionally been based on experience. Only recently has the use of numerical methods such as CFD (Computational Fluid Dynamics) become an important part of the development process. READ MORE

  3. 3. Ultrastructure of the Primary Cell Wall of Softwood Fibres Studied using Dynamic FT-IR Spectroscopy

    Author : Jasna Stevanic Srndovic; Lars Wågberg; Per M. Claesson; Paul Gatenholm; KTH; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; primary cell wall; polymer interactions; viscoelasticity; dynamic FT-IR spectroscopy; dynamic 2D FT-IR spectroscopy; cellulose; xyloglucan; pectin; protein; lignin; low degree sulphonation; cellulose allomorphs; Wood fibre and forest products; Träfiber- och virkeslära;

    Abstract : The primary cell wall is a complex multipolymer system whose composite structure has been mostly determined from chemical and biochemical studies. Although the primary cell wall serves a central role, with regard to the connective properties of fibres, knowledge about the interactions among the polymers, when it comes to the mechanical properties, is very limited. READ MORE

  4. 4. Modification of fluff pulp fibres: Cross-linking and alkali extraction

    Author : Kristoffer Lund; Chalmers tekniska högskola; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; fibre network; dry defibration; network strength; fluff pulp; Absorption; cross-linking; alkali extraction; kraft pulp;

    Abstract : Fluff pulp has been one of the key components of hygienic products, such as diapers, for many years. Fluff pulp is dry defibrated and air-laid into the absorption core of diapers. The introduction of superabsorbent polymers (SAPs) in the 1980s decreased the dependence on fluff pulp, as the SAPs became the main absorbing material. READ MORE

  5. 5. Micromechanical Modelling of Wood and Fibre Properties

    Author : Kent Persson; Byggnadsmekanik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Environmental technology; Byggnadsteknik; Building construction; Microfibril angle; Density; Hygroexpansion; Stiffness; Simulation; Wood; Fibre; pollution control; Miljöteknik; kontroll av utsläpp; Material technology; Materiallära; materialteknik;

    Abstract : Wood is a material with mechanical properties that vary markedly, both within a tree and among trees. Moisture changes lead to shrinkage or swelling and modify the mechanical properties. READ MORE