Sökning: "extractives"

Visar resultat 41 - 45 av 45 avhandlingar innehållade ordet extractives.

1. 41. Interactions between non-polar surfaces in water: Fokus on talc, pitch and surface roughness effects

   Författare :Viveca Wallqvist; Per Claesson; Janne Laine; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Talc; surface forces; capillary attraction; hydrophobic interaction; pitch control; wetting agent; dispersing agent; adsorption; imbibition; absorption; permeation; atomic force microscopy; colloidal probe; Hamaker constant; surface roughness; nanostructure.; Talk; kapillärattraktion; ytkrafter; hydrofob växelverkan; hartskontroll; vätningsmedel; dispergeringsmedel; adsorption; uppsugning; absorption; permeabilitet; atomkraftsmikroskopi; kolloidal partikel; Hamakerkonstant; ytråhet; nanostrukturerad yta.; Surface and colloid chemistry; Yt- och kolloidkemi; Physical chemistry; Fysikalisk kemi; Chemistry; Kemi;

   Sammanfattning : The aim of this thesis work was to gain understanding of the interactions between talc mineral and surfaces, liquids and chemicals relevant for industrial applications, such as pulp and paper. Talc is used in the pulp and paper industry as a filler pigment, in control of pitch (lipophilic extractives) deposits and as a coating pigment. LÄS MER

3. 42. On the Internal Sizing Mechanisms of Paper with AKD and ASA Related to Surface Chemistry, Wettability and Friction

   Författare :Rauni Seppänen; Mark Rutland; John Roberts; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Surface and colloid chemistry; Yt- och kolloidkemi;

   Sammanfattning : Paper and board are hydrophobized (sized) to control the spreading and absorption of waterbased inks and retard the absorption and edge penetration of liquid packaging by aqueous liquids. Alkenyl ketene dimers (AKD) and alkenyl succinic anhydride (ASA) are synthetic sizing agents that are generally used under neutral or slightly alkaline papermaking conditions. LÄS MER

4. 43. Combination of heating and preservative impregnation of wood for outdoor exposure

   Författare :Ekaterina Sidorova; Magdalena Kutnik; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wood Physics; Träfysik;

   Sammanfattning : The research is presented as a composite thesis containing a theoretical explanatory review based on four scientific articles. The thesis covers the investigation of wood modification methods, which in the future could possibly be developed further to enhance the performance of wood products in an efficient and economical way. LÄS MER

5. 44. Storage of Hydrogen Peroxide Bleached Mechanical Pulp : Reduction in Reflectance over the Visible Spectrum

   Författare :Sofia Enberg; Per Engstrand; Magnus Paulsson; Mats Rundlöf; Patrik Axelsson; Øyvind Eriksen; Yonghao Ni; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : The objective of this thesis is to determine possible causes of the darkening of hydrogen peroxide bleached mechanical pulp over the visible spectrum and their relative contributions. It focuses on both process conditions and the composition of the pulp and the dilution water, including additions or losses of material along the process line from the bleach tower to the paper machine. LÄS MER

7. 45. Frictional studies and high strain rate testing of wood under refining conditions

   Författare :Birgitta Svensson; Hans Höglund; Per A. Gradin; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Friction; High strain rate testing; Wood; Mechanical pulping; Tribology; Refining; Energy consumption; Chemical engineering; Kemiteknik;

   Sammanfattning : When producing thermomechanical pulps (TMP), wood chips and fiber material are loaded mechanically in a disc-refiner to separate the fibers and to make them flexible. In the process, much of the energy supplied is transferred to the fiber material through cyclic compression, shear and friction processes. LÄS MER