Search for dissertations about: "hc"

Showing result 1 - 5 of 173 swedish dissertations containing the word hc.

  2. 1. Cryptanalysis of Selected Stream Ciphers

    Author : Paul Stankovski; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stream cipher; cryptanalysis; FCSR; state recovery; linear relations; optimal sampling; distinguisher; HC; nonrandomness; greedy bit set algorithm.;

    Abstract : The aim of this dissertation is to show some cryptanalytical results on a selection of stream ciphers. We have grouped theory and results into three main parts. The first part focuses on the FCSR-based constructions X-FCSR and F-FCSR-H v3. For the X-FCSR family of stream ciphers we perform a severe state recovery attack. READ MORE

  4. 2. Experimental and kinetic studies of H2 effect on lean exhaust aftertreatment processes: HC-SCR and DOC

    Author : Muhammad Mufti Azis; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HC-SCR; NO oxidation.; Hydrogen effect; NOx reduction; Kinetic modeling; Silver Alumina; DOC; Platinum Alumina;

    Abstract : With a growing concern to lower greenhouse gas emissions from road transportation, lean burn and diesel engines will keep playing an important role in the future. Development of a highly efficient and durable process to reduce NOx to N2 becomes a challenging issue especially in the presence of ample O2 concentration as in lean burn exhaust. READ MORE

  5. 3. Studies of hydrocarbon-assisted selective catalytic reduction of nitrogen oxides - DME as reductant and reaction mechanism over silver/alumina

    Author : Stefanie Tamm; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ZSM-5; NCO; HC-SCR; Dimethyl ether; reaction mechanism; silver alumina;

    Abstract : Increasing amounts of carbon dioxide are attaining worldwide growing attention as one probable cause for global warming. Together with the expected peak in oil production and an increasing oil demand, this results in a greater interest in more fuel effective lean burn engines (i.e. operation with excess oxygen). READ MORE

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

    Author : Malin Berggrund; Chalmers tekniska högskola; []
    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

  7. 5. Lean NOx reduction over silver-alumina catalysts - Aspects on synthesis, structure and activity

    Author : Hannes Kannisto; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; freeze-drying; HC-SCR; DRIFTS.; aromatic hydrocarbons; silver-alumina; Lean NOx reduction; selective catalytic reduction; sol-gel; characterization; catalyst preparation; kinetic modeling;

    Abstract : The aim of this thesis is to increase the understanding of how to design highly active silver-alumina catalysts for selective catalytic reduction of NOx with hydrocarbons (HC-SCR) in oxygen excess at low temperatures (150-250 °C). Silver-alumina catalysts have been prepared using different methods, including a new unique preparation method developed during the thesis project. READ MORE