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4 Uppsatser om Extractive acetylation - Sida 1 av 1

Metodutveckling för analys av klorfenoler i jord samt analys av förorenad jord från ett sågverk

In this final thesis, an existing method for analysis of chlorophenols (CP) in bottom sediments has been updated and adjusted for analysis of chlorophenols in soil. The covalent bonds between the chlorophenols and the soil matrix were broken through basic hydrolysis and the chlorophenols were then separated from the water phase through addition of sulphuric acid followed by ether extraction. The chromatography was improved through Extractive acetylation of the chlorophenols.The updated method was then applied on soil samples from a contaminated area (a former sawmill in Hyttsjö, Östergötland, Sweden).The analyse was preformed by GC/MS with respect to 2-MonoCP, 4-MonoCP, 2,4-DiCP, 2,6-DiCP, 2,4,6-TriCP, 2,3,4,6-TetraCP and pentachlorophenol (PCP).Contamination of chlorophenols in nature can be explained by the former use of wood preservative chemicals based on chlorophenols. In the 1960s and the 1970s these chemicals were used in Sweden, but due to their toxicity they were banned by the Swedish government in 1978.In Hyttsjö a pentachlorophenol-based product named Santobrite was used for several years. The concentration of PCP in the soil samples from Hyttsjö varied from 0.2->1.8 ng/mg dry substance.

Trä som fasadmaterial ? behandling och beständighet

Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.

Flavour improvement of water solutions comprising bitter amino acids

The aim of this project was to improve taste of a liquid food product, comprising extremelybitter and unpalatable amino acids and one unrevealed ingredient. The amino acids were Lleucine,L-isoleucine, L-valine, L-threonine and L-lysine monohydrochloride. Experimentaldesign was set up as a screening of water solutions comprising these ingredients (called BCAAsolutions) and added ingredients with potential to improve flavour. BCAA solution withingredients that were potential bitterness suppressors were evaluated in flavour, bitternessand/or palatability. Solutions of separate amino acids were also studied.

Effects of storage time, die channel length and moisture content on pellet quality of lodgepole pine (Pinus contorta Dougl. var. latifolia)

The use of renewable resources is rapidly increasing in Sweden, especially the use of fuel pellets. Through pelletizing the energy content per volume unit is greatly increased and the pellets are more homogeneous with regard to moisture content, particle size and density compared to unrefined fuels like forest residues and chips. For further development of the Swedish pellet industry, the use of different assortments from lodgepole pine (Pinus contorta Dougl. var. latifolia) is of particular interest, mainly because of its high volume production.