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1. 1. Generation, stability and migration of montmorillonite colloids in aqueous systems

   Författare :Sandra García García; Mats Jonsson; Tiziana Missana; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bentonite; montmorillonite; colloid stability; colloid migration; geological disposal; nuclear waste; granitic fractures; ; Environmental chemistry; Miljökemi; Environmental toxicology; Miljötoxikologi; Surface and colloid chemistry; Yt- och kolloidkemi; Nuclear chemistry; Kärnkemi;

   Sammanfattning : In Sweden the encapsulated nuclear waste will be surrounded by compacted bentonite in the granitic host rock. In contact with water-bearing fractures the bentonite barrier may release montmorillonite colloids that may be further transported in groundwater. LÄS MER

3. 2. NH3-SCR chemistry for NOx abatement: Influence of zeolite support on N2O formation & phosphorus species addition

   Författare :Joonsoo Han; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Copper; NH3 SCR chemistry; Zeolite topology; N2O; Phosphorus poisoning;

   Sammanfattning : Different lattice arrangements of Si, Al, and O atoms result in a variety of pore dimensions and zeolite channel network systems, giving rise to different physicochemical environments inside the catalyst cage. The objective of the thesis work was to understand the influence of zeolite topology on NH3-assisted SCR chemistry over CHA, MFI, and BEA frameworks, on the formation of N2O and the addition of phosphorus species to attain fundamental insight into NOx emission control. LÄS MER

4. 3. Catalyst Design for the Valorisation of Biomass-derived Furans into Aromatics

   Författare :Guido J.L. de Reijer; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; aromatics; 2; 5-dimethylfuran; gallium; biomass; furans; production of aromatics; zeolites; biomass conversion; catalysis;

   Sammanfattning : Anno 2023, mankind must strive towards a more sustainable chemical industry; one that does not solely rely on fossil fuels but also utilises renewable feedstocks such as biomass. Biomass can be catalytically converted into commodity chemicals such as aromatics, through intermediates like furans. LÄS MER

5. 4. Assessment of human exposure to per- and polyfluorinated compounds (PFCs) : exposure through food, drinking water, house dust and indoor air

   Författare :Ingrid Ericson Jogsten; Gunilla Lindström; Bert van Bavel; Stuart Harrad; Örebro universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; human exposure; per- and polyfluorinated compunds PFCs ; dietary intake; drinking water; indoor environment; TECHNOLOGY; TEKNIKVETENSKAP; Environmental chemistry; Miljökemi; Chemistry; Kemi; Miljökemi; Environmental Chemistry; Kemi; Chemistry;

   Sammanfattning : Per- and polyfluorinated compounds (PFCs) are detected in humans worldwide but all sources of human exposure have not been fully characterized. The aim of this thesis was to evaluate the contributions from food, water, air and dust as sources for human PFC exposure in the general population. LÄS MER

7. 5. Water film-mediated mineralogical transformations and photocatalytic reactions

   Författare :N. Tan Luong; Jean-Francois Boily; Michael Holmboe; Alejandro Fernandez-Martinez; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; mineral; water films; carbon dioxide; MgO; MnCO3; TiO2; hydroxylation; carbonation; oxidation; transformation; photocatalysis; Inorganic Chemistry; oorganisk kemi; nanomaterials; nanomaterial; Physical Chemistry; fysikalisk kemi;

   Sammanfattning : Mineral particles capture water vapor in the atmosphere in the form of water films that are only few monolayers thick. Water films form nanoscale hydration environments that mediate a wide range of important reactions in nature and technology. LÄS MER