Search for dissertations about: "Discoloration"

Showing result 1 - 5 of 28 swedish dissertations containing the word Discoloration.

  2. 1. Biochemical Study and Technical Applications of Fungal Pectinase

    Author : Jing Zhang; Gunnar Johansson; Gunnar Henriksson; Jonas Hafrén; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Pectin; pectinase; polygalacturonan; polygalacturonase; retting; flax; enzymatic retting; pre-incubation; discoloration; pulping; Biokemi; Biochemistry; Biokemi;

    Abstract : Pectinases are a group of enzymes produced by bacteria, fungi, higher plants and animals. Pectinases can modify and degrade pectins, a class of heterogeneous and multifunctional polysaccharides present in middle lamellae and primary cell walls of plants. READ MORE

  4. 2. on the thermal yellowing of TCF- bleached birch kraft pulp

    Author : Anders Granström; KTH; []
    Keywords : Ageing; Brightness reversion; Chalaton; Colour reversion; Dicarboxylic acids; Discoloration; HexA; Hexenuronic acid; Kraft pulp; Metal profile; Thermal yellowing; Xylan;

    Abstract : .... READ MORE

  5. 3. Welds in the lean duplex stainless steel LDX 2101 : effect of microstructure and weld oxides on corrosion properties

    Author : Elin M. Westin; John Ågren; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Duplex stainless steel; welding; weld metal; HAZ; nitrogen; manganese; austenite formation; phase balance; precipitates; pitting resistance; heat input; solidification; element loss; evaporation; deposition; weld oxides; discoloration; mechanical properties; thermo-mechanical simulation; Geeble; GTA; laser; LOM; SEM; EDS; TEM; Leco; EPMA; ferroxyl test; XPS; post weld cleaning; pickling; Materials science; Teknisk materialvetenskap;

    Abstract : Duplex stainless steels are a very attractive alternative to austenitic grades due to their higher strength and good corrosion performance. The austenitic grades can often be welded autogenously, while the duplex grades normally require addition of filler metal. READ MORE

  6. 4. The influence of high temperature on the discoloration and degradation of carbohydrates and on hydrogen peroxide bleaching of spruce TMP

    Author : Louise Logenius; Hans Höglund; Roland Agnemo; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Temperature; metal ions; cellulose; glucuronic acid; UV-Vis spectroscopy; spruce; TMP; hydrogen peroxide bleaching; spectroscopy; optical properties; Chemical engineering; Kemiteknik;

    Abstract : When processing wood to obtain pulp, the fibers are subjected to high temperatureat moisture levels and to the influence of metal ions. Many process developmentshave resulted in utilization of higher temperatures that induce chemical reactionsin the wood fibers. This thesis deals with some aspects of using high temperaturesin pulping processes. READ MORE

  7. 5. Colour Response in Drying of Nordic Hardwoods

    Author : Stefan Stenudd; Thomas Thörnqvist; Timo Kärki; Linnéuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beech; Betula pendula; birch; CIELAB; discolouration; drying; Fagus sylvatica; log storage; oak; press drying; wood colour; Quercus robur; Forestry and Wood Technology; Skog och träteknik;

    Abstract : Colour and appearance of hardwood are of great importance for the interiorand furniture industry. The widespread use of transparent surface treatmentand a fashion that prescribe light colour on many species, means that deviationfrom the ideal have considerable impact on the industrial operations. READ MORE