Sökning: "nitrogen oxides"

Visar resultat 1 - 5 av 178 avhandlingar innehållade orden nitrogen oxides.

  1. 1. Assessing reactive nitrogen flows in European agricultural systems

    Författare :Rasmus Einarsson; Chalmers tekniska högskola; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; food; nitrogen indicator; nitrogen budget; nitrogen; agriculture; nitrogen footprint; uncertainties;

    Sammanfattning : In most ecosystems, nitrogen is a scarce and growth-limiting nutrient. Natural and anthropogenic processes convert unreactive atmospheric dinitrogen (N2) into reactive, bioavailable, nitrogen. LÄS MER

  3. 2. Optimization of Pretreatment of Kraft Pulp with Nitrogen Oxides

    Författare :Urban Öjteg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kappa number; lignins; Nitric acid; Magnesium; spent liquors; viscosity; softwood; oxygen bleaching; Nitrogen dioxide; Manganese; Oxygen; Nitrogen oxides; pretreatment; Kraft pulp;

    Sammanfattning : Modified kraft pulp subjected to oxygen bleaching following pretreatment with 2% nitrogen dioxide for 140 min with the addition of oxygen resulted in low selectivity after subsequent oxygen bleaching. In contrast, pretreatment in the absence of oxygen removed more than 80% of the lignin after oxygen bleaching and still maintained high selectivity (kappa number less than 5 at viscosity 950 dm3/kg). LÄS MER

  4. 3. Oxy-Fuel Combustion - The Control of Nitrogen Oxides

    Författare :Fredrik Normann; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; oxy-fuel; NOx; O2 CO2; combustion; emission; nitrogen oxides;

    Sammanfattning : Oxy-fuel combustion is one of the main candidates for carbon dioxide capture from power plants. In oxy-fuel combustion, oxygen diluted with recycled flue gas oxidizes the fuel. The elimination of air-borne nitrogen generates a flue gas that mainly consists of carbon dioxide and water. LÄS MER

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

    Författare :Elin M. Westin; John Ågren; KTH; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  7. 5. Conversion of nitrogen in a fixed burning biofuel bed

    Författare :Jessica I. Samuelsson; RISE; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biomass; model; fuel nitrogen; fixed bed; nitric oxide; Nitrogen oxides; combustion; measurements; biofuel; grate;

    Sammanfattning : .... LÄS MER