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Showing result 1 - 5 of 153 swedish dissertations matching the above criteria.

2. 1. Capturing Air Pollutants : Photochemical Adsorption and Degradation of SO2, NO2 and CO2 on Titanium Dioxide

   Author : David Michael Langhammer; Lars Österlund; Tomas Edvinsson; Gunnar Niklasson; Günther Rupprechter; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; titanium dioxide; photocatalysis; surface reaction; oxygen vacancies; air pollution; sulfur dioxide; nitrogen dioxide; carbon dioxide; sulfate; nitrate; carbonate; Engineering Science with specialization in Solid State Physics; Teknisk fysik med inriktning mot fasta tillståndets fysik;

   Abstract : Titanium dioxide (TiO2) is a material with many useful properties. It is used most widely as a pigment in white paint, although in technological research it is better known for its ability to catalyze chemical reactions during light absorption. READ MORE

4. 2. Delignification and bleachability of kraft pulps pretreated with nitrogen dioxide

   Author : Per Larsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; chlorine dioxide; oxygen bleaching; molecular mass; paper properties; ozone bleaching; nitrogen dioxide; kraft pulps; pretreatment; gel permeation chromatography; indulin AT; hydrogen peroxide; consecutive alkaline extractions;

   Abstract : .... READ MORE

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

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

   Abstract : 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). READ MORE

6. 4. Molecular Beam Studies of Interactions Between Ice Surfaces and Atmospherically Relevant Molecules

   Author : Liza Romero Lejonthun; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; molecular beam; surface; surface scattering; collision; water ice; ice; chlorine; nitrogen oxides; nitrogen monoxide; nitrogen dioxide; dinitrogen tetroxide; dinitrogen pentoxide; nitric acid; helium; graphite;

   Abstract : The discovery of the ozone hole over Antarctica in 1985 was one of the environmental issues that attracted most attention worldwide in the end of the last century. The cause of the ozone hole formation was proven to be coupled to the emission of chlorofluorocarbons (CFCs). READ MORE

7. 5. Remote Measurements of Ship Emissions

   Author : Niklas Berg; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; airborne; Ship emissions; sulphur dioxide; nitrogen dioxide; DOAS; in situ measurements; carbon dioxide;

   Abstract : The combustion of sulphur-containing fossil fuels gives rise to emissions of sulphurdioxide. Nitrogen oxides are also emitted when fuels are burned. The InternationalMaritime Organization (IMO) has ratified regulations regarding Sulphur Fuel Content(SFC) and NOx emissions from the shipping sector. READ MORE