Sökning: "kväveoxid"

Visar resultat 1 - 5 av 42 avhandlingar innehållade ordet kväveoxid.

  1. 1. On the Impact of Piston Motion and In-Cylinder Charge Composition on Energy Release, Auto Ignition and Emission Formation in Premixed Charge Internal Combustion Engines

    Författare :Ola Stenlåås; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bränslen; sprängämnen; Carbochemistry; petrochemistry; fuels and explosives technology; Petrokemi; Internal Combustion Engine; Emission; SI; Spark Ignition; HCCI; Homogeneous Charge Compression Ignition; zone model; Chemical Kinetic; Engine simulation; Reformed Methanol; Hydrogen; Knock; Auto Ignition; NO; Piston Motion; Nitric Oxide; Premixed Charge;

    Sammanfattning : The results presented in this thesis can be divided into four areas of investigation: Investigation of the effect of new volume-crank angle relations on engine emissions, power and efficiency; investigation of nitrogen oxides effect on auto ignition and knock in SI engines; investigation of premixed SI and HCCI engine operation with the alternative fuels hydrogen and reformed methanol gas (RMG); software development of a detailed chemical kinetics zonal engine model. Model development of the in-house two-zone chemical kinetic code focused on expansion of the Jacobian matrix to allow simulations of variable in-cylinder charge. LÄS MER

  2. 2. NO, Immunosuppression and Tumor Immmunotherapy

    Författare :Pontus Hegardt; Neurokirurgi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Immunology; serology; transplantation; Immunologi; serologi; IL-18; IFN-gamma; rat; colon carcinoma; glioma; tumor immunotherapy; immunosuppression; NO; iNOS;

    Sammanfattning : This study aims at clarifying the role of NO in the immunosuppression induced by in vivo tumor growth and by tumor immunotherapy, and determining whether the inhibition of NO production can be used as an adjuvant in tumor immunotherapy. We have shown previously that tumor cells, glioma (N32) and colon carcinoma (H1D2), when genetically engineered to express such immune stimulatory cytokines as IFN-g and IL-18, induce strong anti-tumor immune response, in immunized tumor-free rats, whereas only a limited therapeutic effect is achieved in rats in which a tumor has already become established. LÄS MER

  3. 3. Prevention of intimal hyperplasia after balloon angioplasty and / or stent insertion. or How to mend a broken heart - Just say NO

    Författare :Jan Harnek; Kardiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Kardiovaskulära systemet; Cardiovascular system; Remodeling. Endothelium-derived factors. Self-expanding stents. Restenosis. Scanning -electron microscopy. Endothelial factors. Nitric oxide. Intimal hyperplasia. Angioplasty. Stents. Interventional procedures. Endothelium.;

    Sammanfattning : Background: Restenosis is the most frequently occurring adverse event after percutaneous intravascular treatment of atherosclerotic lesions, which limits long-term patency of the intervention. Objective: The aim of the study was to evaluate if minimizing vascular injury during treatment by insertion of self-expanding stents or modifying the reparative mechanisms by local drug delivery can reduce restenosis. LÄS MER

  4. 4. Thermodynamic Simulation of HCCI Engine Systems

    Författare :Olof Erlandsson; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HAM; Turbine; Compressor; Turbocharger; Engine; Modeling; HCCI; Simulation; Motors and propulsion systems; Motorer; framdrivningssystem;

    Sammanfattning : This thesis focuses on engine system simulation using thermodynamics and chemical kinetic models to investigate the performance and efficiency of Homogeneous Charge Compression Ignition (HCCI) engines for stationary applications. It includes the development of software as well as models for engine, turbocharger, intercooler, inlet and exhaust manifolds, wastegate valve, inlet air humidifier, inlet air heater and more. LÄS MER

  5. 5. Homocysteine and Coronary Artery Disease With special Reference to Biochemical Effects Of Vitamin Therapy

    Författare :Torfi Jonasson; Kardiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Klinisk kemi; Clinical chemistry; pyridoxine.; oxidative stress; lipid peroxidation; inflammation; homocysteine; endothelial function; folate; F2-isoprostanes; cystatine C; Acut coronary syndrome; cardiovascular disease; asymmetric dimethylarginine; cobalamine;

    Sammanfattning : An elevated plasma level of homocysteine has been suggested as a risk factor for cardiovascular disease. The objectives of this thesis were to study the influence of renal function on homocysteine levels in patients with coronary artery disease and to explore the association of elevated plasma levels of homocysteine to oxidative stress, inflammation, and endothelial dysfunction. LÄS MER