Sökning: "Wood"

Visar resultat 1 - 5 av 1278 avhandlingar innehållade ordet Wood.

  1. 1. Wood Fingerprints : Recognition of Sawn Wood Products

    Författare :Tobias Pahlberg; Luleå tekniska universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Träproduktutveckling; Wood Products Engineering;

    Sammanfattning : This thesis deals with wood fingerprints and presents ways to track sawn wood products through an industrial process using cameras. The possibility to identify individual wood products comes from the biological variation of the trees, where the genetic code, environment and breakdown process creates a unique appearance for every board. LÄS MER

  2. 2. Moisture-induced stress and distortion of wood : A numerical and experimental study of wood's drying and long-term behaviour

    Författare :Sara Florisson; Sigurdur Ormarsson; Johan Vessby; Kent Persson; Linnéuniversitetet; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; LANTBRUKSVETENSKAPER; ENGINEERING AND TECHNOLOGY; AGRICULTURAL SCIENCES; analytical method; calibration; controlled climate; creep; distortion; experimental methodology; FEM; fibre orientation; mechano-sorption; moisture transport; natural climate; Norway spruce; numerical model; three-dimensional; timber beam; validation; wood; Byggteknik; Civil engineering; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : With the current advances made in three-dimensional modelling of wood, it is possible to provide an overall picture of moisture flow, and moisture-induced stress and deformations, whereas previously, experiments only provided local measurements. The main aim of the doctoral thesis is to investigate the possibilities of the developed three-dimensional numerical model to predict the behaviour of wood when simultaneously exposed to a mechanical load and a particular climate. LÄS MER

  3. 3. Acid-catalyzed Liquefaction of Industrial Side-streams for Producing Wood Adhesives and Particleboard

    Författare :Wen Jiang; Stergios Adamopoulos; Sheikh Ali Ahmed; Sergej Medved; Carsten Mai; Johannes Konnerth; Linnéuniversitetet; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Bark; Catalysts; Industrial side-streams; Liquefaction; Oat husks; Optimization; Particleboards; Polyurethane; Polyhydric alcohols; Wood adhesives; Wood sawdust; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Big quantities of residues and side-streams are generated annually from forest-based and agricultural industries all around the world and present a relatively unexplored renewable resource. Due to the absence of a regularly updated and systematic database of supply, industrial residues and side-streams usually end up in landfill disposal, are used for energy generation, or remain at the production sites. LÄS MER

  4. 4. Adhesion to machined and laser ablated wood surfaces

    Författare :Micael Stehr; KTH; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; ablation; adhesion; checks; coating; cracks; excimer laser; gluing; IR laser; mechanical machining; mechanical weak boundary layer; microscopy; notched specimens; pine; planing; sample preparation; sawing; scanning electronmicroscopy; spruce; tip-cracks; UV laser; weak boundary layer; wood;

    Sammanfattning : This thesis is a contribution to the R&D-program ValueActivation at KTH,Division of Wood Technology and Processingand containsfive papers related to the evaluation and development ofmachining techniques (mechanical and irradiation treatments)whereby weak boundaries at the wood surfaces in the form of(mechanical) weak boundary layers and (micro) cracks due tomechanical treatment can be avoided.The first paper describes the development of a method–using a UV laser–to study the mechanically weakenedboundaries. LÄS MER

  5. 5. Wood Hemicelluloses - Fundamental Insights on Biological and Technical Properties

    Författare :Jennie Berglund; Mikael Lindström; Gunnar Henriksson; Francisco Vilaplana; Jakob Wohlert; Martin Lawoko; Maija Tenkanen; KTH; []
    Nyckelord :AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; TEKNIK OCH TEKNOLOGIER; LANTBRUKSVETENSKAPER; LANTBRUKSVETENSKAPER; ENGINEERING AND TECHNOLOGY; AGRICULTURAL SCIENCES; AGRICULTURAL SCIENCES; hemicellulose; wood; glucomannan; xylan; structure; acetylation; flexibility; solubility; interaction with cellulose; stability.; hemicellulosa; trä; glukomannan; xylan; struktur; acetylering; flexibilitet; löslighet; interaktion med cellulosa; stabilitet.; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Hemicelluloses are a group of heterogeneous polysaccharides representing around 30 % of wood where the dominating types are xylans, glucomannans and xyloglucans. Hemicelluloses complex molecular structure makes it difficult to understand the relationship between structure and properties entirely, and their biological role is not yet fully verified. LÄS MER