Search for dissertations about: "chemical effects"

Showing result 6 - 10 of 1863 swedish dissertations containing the words chemical effects.

  2. 6. Aging effects on commercial lean NOx trap catalysts

    Author : Jesus De Abreu Goes; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aging; thermal degradation; sulfur poisoning; characterization; commercial lean NOx traps; NOx storage and reduction;

    Abstract : As a countermeasure to global warming, vehicles with low carbon emissions are being investigated by promoting lean-burn engines and high combustion efficiencies. However, one limitation to the increasing use of these engines is the need to develop corresponding catalytic systems for controlling the nitrogen oxide (NOx) emissions in their lean exhaust. READ MORE

  4. 7. Fundamentals of NH3-SCR and SOx chemistry over copper zeolite for the control of NOx and greenhouse gas (N2O) emissions

    Author : Joonsoo Han; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; DeNOx; Cu SSZ-13; NH3-SCR; N2O; EATS; SO3; ammonium nitrate; SO2;

    Abstract : The release of N2O over Cu-zeolite was investigated due to the critical contribution it makes to the atmosphere as one of the greenhouse gases (GHGs). An exhaust after-treatment system (EATS) for heavy-duty vehicles that uses Cu/SSZ-13 as the selective catalyst reduction (SCR) catalyst experiences not only a variety of flow, temperature and chemical conditions but is also exposed to various resulting contaminants. READ MORE

  5. 8. Catalytic Conversion of Undesired Organic Compounds to Syngas in Biomass Gasification and Pyrolysis Applications

    Author : Pouya H. Moud; Klas Engvall; Klas J. Andersson; Roberto Lanza; Mats Ahmadi Götelid; Anker Degn Jensen; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tar reforming; biomass gasification; Ni-based catalyst; potassium; sulfur; pyrolysis gas; bio-crude conditioning; gas conditioning; Fe-based catalyst; tjärreformering; biomassaförgasning; Ni-baserad katalysator; kalium; svavel; pyrolysgas; konditionering bio-råolja; gaskonditionering; Fe-baserad katalysator; Chemical Engineering; Kemiteknik;

    Abstract : Reliable energy supply is a major concern and crucial for development of the global society. To address the dependency on fossil fuel and the negative effects of this reliance on climate, there is a need for a transition to cleaner sources. An attractive solution for replacing fossil-based products is renewable substitutes produced from biomass. READ MORE

  6. 9. The cell wall ultrastructure of wood fibres : effects of the chemical pulp fibre line

    Author : Jesper Fahlén; Ulf W. Gedde; Drek G. Gray; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; atomic force microscopy; cellulose; cell wall; drying; fiber; Kemiteknik; Chemical engineering; Kemiteknik;

    Abstract : Knowledge of the ultrastructural arrangement within wood fibres is important for understanding the mechanical properties of the fibres themselves, as well as for understanding and controlling the ultrastructural changes that occur during pulp processing. The object of this work was to explore the use of atomic force microscopy (AFM) in studies of the cell wall ultrastructure and to see how this structure is affected in the kraft pulp fibre line. READ MORE

  7. 10. Nanoplasmonic Spectroscopy of Single Nanoparticles Tracking Size and Shape Effects in Pd Hydride Formation

    Author : Svetlana Syrenova; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hole-mask colloidal lithography; enthalpy of formation; palladium nanoparticles and nanocrystals; metal-hydrogen interactions; shrinking-hole colloidal lithography; localized surface plasmon resonance; dark field scattering spectroscopy; single particle spectroscopy; nanoscale effects; plasmonic sensors;

    Abstract : Localized surface plasmon resonance (LSPR) is a phenomenon of collective oscillation of conduction electrons in metal nanoparticles smaller than the wavelength of light that is used for its excitation. Plasmonic metal nanoparticles are able to confine light to extremely small volumes around them, i.e. below the diffraction limit. READ MORE