Sökning: "Mineralisation"

Visar resultat 1 - 5 av 62 avhandlingar innehållade ordet Mineralisation.

1. 1. Geophysical vectoring of mineralized systems in northern Norrbotten

   Författare :Roshanak Vadoodi; Thorkild Maack Rasmussen; Maxim Smirnov; Behrooz Oskooi; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetotelluric; Electrical Conductivity; Potential Field; 3D Inversion; Mineralisation; Classification; Self-Organizing Map SOM ; Exploration Geophysics; Prospekteringsgeofysik;

   Sammanfattning : The Fennoscandian Shield as a part of a large Precambrian basement area is located in northern Europe and hosts economically important mineral deposits including base metals and precious metals. Regional geophysical data such as potential field and magnetotelluric data in combination with other geoscientific data contain information of importance for an understanding of the crustal and upper mantle structure. LÄS MER

3. 2. Nutrient and Organic Matter Dynamics in Beech Forest Floors, in Relation to the Presence of Ground Flora

   Författare :Frida Andréasson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bioavailability; mineralisation; soil acidity; soil matrix solution; soil leachate; nitrate; ammonia; dissolved organic carbon; beech; Ground flora; forest floor; O horizon; A horizon; Plant ecology; Växtekologi;

   Sammanfattning : The objective of this thesis was to quantify differences between adjacent patches with and without ground flora of Deschampsia flexuosa L. Trin or Anemone nemorosa L. in two acid European beech (Fagus sylvatica L.) forest floors in south-west of Sweden. LÄS MER

4. 3. Portland Cement Clinker - Composition and Hydration

   Författare :Anna Emanuelson; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; mineralisation; hydration; polymorphism; substitutions; ferrite; aluminate; belite; alite; Portland cement clinker; phase analysis; Oorganisk kemi; Material technology; Materiallära; materialteknik;

   Sammanfattning : The crystal structures of the main Portland cement clinker phases are reviewed and two anion centered models of Ca3SiO5 and Ca2SiO4 are presented. The effects of minor elements on the clinkering process, and on the qualitative and quantitative phase compositions of Portland cement clinker are discussed. LÄS MER

5. 4. The role of benthic macrofauna in nitrogen cycling in eutrophic lake sediment

   Författare :Jonas Martin Svensson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; nitrogen retention; nitrous oxide; oligochaetes; chironomids; mineralisation; nitrification; denitrification; eutrophic; sediment; lake; Macrofauna; nitrogen cycling; fish reduction.; Ecology; Ekologi;

   Sammanfattning : This thesis concerns the role of sediment-living macrobenthos in the cycling of nitrogen species and nitrogen transformation in eutrophic freshwater sediments. In my thesis I have, employing 15N-isotope techniques in laboratory experiments, shown the importance of infaunal chironomid larvae and oligochaetes on denitrification in eutrophic lake sediments. LÄS MER

7. 5. Mineralisation rates of natural organic matter in surface sediments affected by physical forces

   Författare :Carina Ståhlberg; Bo Svensson; Lars Rahm; David Bastviken; Anders Tengberg; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sediment; Organic matter mineralisation; Organic matter degradation; Redox; Electron acceptor; Resuspension; Advective pore water flow; Other chemistry; Övrig kemi;

   Sammanfattning : Nedbrytning av organiskt material är en nyckelfaktor som påverkar omvandlingar av de många grundämnen som utgör eller är associerade till just organiskt material. En stor del av nedbrytningen av akvatiskt organiskt material (OM) sker i gränsskiktet mellan sediment och vatten. LÄS MER