Search for dissertations about: "hydrothermal stability"

Showing result 1 - 5 of 23 swedish dissertations containing the words hydrothermal stability.

  1. 1. Hydrothermal Liquefaction of Lignin into Bio-Oil

    University dissertation from ; Chalmers tekniska högskola; Gothenburg

    Author : Huyen Nguyen Lyckeskog; [2016]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydrothermal conversion; aging; bio-oil; stability; subcritical water; lignin;

    Abstract : Lignin, one of the three main components of lignocellulosic biomass, is the second most abundant organic polymer found on Earth. Nowadays, most of the lignin (almost 99%) produced in the Kraft pulping process is used as internal fuel. READ MORE

  2. 2. Microfabricated Gas Sensors Based on Hydrothermally Grown 1-D ZnO Nanostructures

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Mingzhi Jiao; Uppsala universitet.; [2017]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gas sensor; zinc oxide; on-chip; hydrothermal growth; nanorods; nanowires; annealing; palladium oxide; photoluminescence; alloy; sensitivity; selectivity; stability;

    Abstract : In this thesis, gas sensors based on on-chip hydrothermally grown 1-D zinc oxide (ZnO) nanostructures are presented, to improve the sensitivity, selectivity, and stability of the gas sensors.Metal-oxide-semiconductor (MOS) gas sensors are well-established tools for the monitoring of air quality indoors and outdoors. READ MORE

  3. 3. Hydrothermally induced changes of lean NOx reduction over Cu-ZSM-5 and stability improvements by synthesis modification

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Malin Berggrund; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; hydrothermal stability; Cu-ZSM-5; propene; lean NOx reduction; HC-SCR; in-situ DRIFT;

    Abstract : The growing concern about the global warming coupled with the increasing emissions of the greenhouse gas carbon dioxide, combined with the climbing oil price, drives the interest to more fuel efficient lean combustion engines for automotive applications. Such engines require new technical solutions for reduction of NOx in the oxygen rich exhaust gases, where a conventional three-way catalyst cannot be used. READ MORE

  4. 4. Studies of the influence of ZSM-5 synthesis on activity and stability of Cu-ZSM-5 in leand NOx reduction

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Malin Berggrund; [2008]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HC-SCR; Cu-ZSM-5; catalysis; propene; lean NOx reduction; hydrothermal stability;

    Abstract : The growing concern about the global warming coupled with the increasing emissions of the greenhouse gas carbon dioxide, combined with the climbing oil price, drives the interest to more fuel efficient lean combustion engines for automotive applications. Such engines require new technical solutions for reduction of NOx in the exhaust gases, which are in excess oxygen, where a conventional three-way catalyst cannot be used to reduce NOx. READ MORE

  5. 5. Metal-exchanged zeolites for NH3-SCR applications - Activity and Deactivation studies

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Soran Shwan; [2014]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; modeling; NOX.; Hydrothermal; Chemical; Kinetic; Copper; Deactivation; Iron; Zeolite; Nitrogen oxides; NH3; Ammonia; Catalyst; NSR; Emissions; Poisoning; Ageing; NH3-SCR;

    Abstract : Emissions of nitrogen oxides (NOX) formed during the burning process in internal combustion engines is a major contributor to global air pollutions. One effective way to reduce NOX in lean environments, i.e. oxygen excess is selective catalytic reduction with ammonia (NH3-SCR). READ MORE