Sökning: "Picea abies"

Visar resultat 36 - 40 av 179 avhandlingar innehållade orden Picea abies.

  1. 36. Extended impregnation kraft cooking of softwood : Effects on reject, yield, pulping uniformity, and physical properties

    Författare :Katarina Karlström; Mikael E. Lindström; Elisabet Brännvall; Kristofer Gamstedt; Anna Jacobs; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high kappa number pulp; extended impregnation; softwood; spruce; picea abies; pine; pinus sylvestris; uniform delignification; kappa number distribution; reject; yield; tensile index; tensile stiffness index; SCT; starch multilayers; mechano-sorptive creep; hygroexpansion; dimensional stability; eucalypt; birch; acacia; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : Converting wood into paper is a complex process involving many different stages, one of which is pulping. Pulping involves liberating the wood fibres from each other, which can be done either chemically or mechanically. LÄS MER

  3. 37. Effects of future climate on carbon assimilation of boreal Norway spruce

    Författare :Marianne Hall; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bud development; climate change; empirical models; gas exchange; photosynthesis; Picea abies; seasonality; whole-tree chambers;

    Sammanfattning : In boreal forests, the main factors limiting biomass production are the harsh climate, which combines a short growing season and low annual levels of incoming solar energy, and the limited availabilit... mery of nitrogen. LÄS MER

  4. 38. Spiral Grain in Norway Spruce

    Författare :Harald Säll; Thomas Thörnqvist; Rolf Birkeland; Växjö universitet; []
    Nyckelord :Spiral grain angle; drying deformation; warp; wood quality; Norway spruce; Picea abies; FORESTRY; AGRICULTURAL SCIENCES and LANDSCAPE PLANNING; SKOGS- och JORDBRUKSVETENSKAP samt LANDSKAPSPLANERING;

    Sammanfattning : Wood is a major construction material that is used in many contexts, and for different purposes. Serious problems may arise, however, when moisture related deformations as twist occur in wood used in different types of building structures, joinery and furniture. LÄS MER

  5. 39. Above Ground Durability of Swedish Softwood

    Författare :Åsa Blom; Mikael Bergström; Thomas Thörnqvist; Birger Eikenes; Växjö universitet; []
    Nyckelord :above ground; durability; field test; mass loss; Mycologg; Norway spruce; permeability; Picea abies; Pinus sylvestris; Scots pine; FORESTRY; AGRICULTURAL SCIENCES and LANDSCAPE PLANNING; SKOGS- och JORDBRUKSVETENSKAP samt LANDSKAPSPLANERING;

    Sammanfattning : This thesis describes aspects of durability of Swedish softwood in above ground applications. The thesis consists of a summary of nine papers, which all aim to explain the existing variation in above ground microbial durability and moisture sensitivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris). LÄS MER

  7. 40. Distributions Of Fiber Characteristics As A Tool To Evaluate Mechanical Pulps

    Författare :Sofia Reyier Österling; Per Engstrand; Hans Höglund; Olof Ferritsius; Rita Ferritsius; Hans Ersson; Per Gradin; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber; fibre; fiber characteristics; fiber dimension; fiber properties; mechanical pulp; FiberLab; raw data; distribution; fiber wall thickness; BIN; bonding ability influence; bonding indicator; bonding ability; fiber width; fibrillation; collapse resistance; laboratory sheet; fiber analyzer; optical analyzer; TMP; CTMP; SGW; sheet model; prediction; fiber characterization; hydrocyclone; fractionation; kernel density estimation; KDE; diffusion mixing; acoustic emission; F0.90; Norway spruce; Picea abies;

    Sammanfattning : Mechanical pulps are used in paper products such as magazine or news grade printing papers or paperboard. Mechanical pulping gives a high yield; nearly everything in the tree except the bark is used in the paper. This means that mechanical pulping consumes much less wood than chemical pulping, especially to produce a unit area of printing surface. LÄS MER