Sökning: "oak wood"

Visar resultat 21 - 25 av 28 avhandlingar innehållade orden oak wood.

  1. 21. Holocene climate change and peatland dynamics in southern Sweden based on tree-ring analysis of subfossil wood from peat deposits

    Författare :Johannes Edvardsson; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; The Holocene.; Peatland development; Scots pine; Palaeoclimatology; Dendrochronology; Subfossil trees; Raised bog; Palaeohydrology;

    Sammanfattning : Dendrochronological analysis was applied to subfossil remains of Scots pine (Pinus sylvestris L.) buried in South Swedish peat deposits. LÄS MER

  3. 22. Effects of Cell Wall Structure on Tensile Properties of Hardwood : Effect of down-regulation of lignin on mechanical performance of transgenic hybrid aspen. Effect of chemical degradation on mechanical performance of archaeological oak from the Vasa ship

    Författare :Ingela Bjurhager; Lars Berglund; Ulrike Wegst; KTH; []
    Nyckelord :tensile strength; transgenic hybrid aspen; lignin down-regulation; the Vasa ship; chemical degradation; longitudinell draghållfasthet; transgen hybridasp; ligninnedreglering; Vasaskeppet; kemisk nedbrytning; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : Wood is a complex material and the mechanical properties are influencedby a number of structural parameters. The objective of this study has been toinvestigate the relationship between the structure and the mechanical propertiesof hardwood. Two levels were of special interest, viz. LÄS MER

  4. 23. Habitat requirements and preservation of the beetle assemblages associated with hollow oaks

    Författare :Nicklas Jansson; Per Milberg; Karl-Olof Bergman; Simon Grove; Linköpings universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : One of the most endangered assemblages of species in Europe is saproxylic beetles associated with old trees. To be able to conserve these species there is a need of developing methods to survey the fauna and to evaluate the conservation value of different oak habitats, develop instruments for landscape planning and detailed knowledge of species habitat requirements. LÄS MER

  5. 24. Fractionation of woody biomass : lignin and suberin in focus

    Författare :Ivan Kumaniaev; Joseph Samec; Claudia Crestini; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lignocellulose; lignin; suberin; biomass; palladium; catalysis; flow chemistry; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis is dedicated to the research of fractionation and valorization of different types of woody biomass. In the first part, oak (Quercus suber) and birch (Betula pendula) barks are considered. Bark is the outer layer of wood and is treated as waste in the current wood processing technologies. LÄS MER

  7. 25. In-situ assessment of timber structures - Assessment methods and case studies

    Författare :Thomas Lechner; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; non-destructive testing NDT ; historical structures; density; In-situ assessment; timber structures; mechanical properties; assessment methods; X-ray;

    Sammanfattning : In the assessment of timber structures, diagnostic investigations with reference to the condition and structural performance of these structures are necessary and often require appropriate health monitoring techniques. This thesis covers four aspects within the research area of the in-situ assessment of timber structures based on scientific knowledge and guidelines to perform assessment of existing timber structures:IDetermination of density of wood with portable X-rayThe mechanical performance of timber is often strongly related to the density of wood. LÄS MER