PT Unknown AU Faßheber, N TI Laser spectroscopic shock tube studies on NOx and CO forming bimolecular reactions of NCN, HNO and HCO PY 2015 PU Christian-Albrechts-Universität zu Kiel WP https://macau.uni-kiel.de/receive/diss_mods_00017475 LA en DE shock tube; chemical kinetics; Laser diagnostic; NOx formation; Stoßrohr; Kinetik; Laserdiagnostik; NOx-Bildung AB Five rate constant expressions for combustion relevant bimolecular reactions of NCN, HNO and HCO have been measured directly behind shock waves. NCN and HNO are known as short-lived flame intermediates that are involved in the formation of nitrogen oxide (NOx) pollutants. HCO is a key radical on the main oxidation pathway of hydrocarbons yielding CO. Accurate knowledge of the rate constants of all involved reactions in the ensuing complex reaction mechanisms makes it possible to develop strategies to (at least) reduce the problem of pollutant formation in combustion processes. Concentration-time profiles of NCN radicals have been detected via UV laser absorption spectroscopy to measure the rate constants of the reactions NCN + H, NCN + H2, and NCN + O2. The thermal decomposition of cyanogen azide (NCN3) was used as quantitative NCN source behind shock waves. The extremely toxic and highly explosive NCN3 had to be directly synthesized from the reaction of NaN3 with BrCN since it could not be purified. The thermal decomposition of ethyl iodide (C2H5I) has been used as high temperature H atom source. The rate constant of the reaction NCN + H, which critically determines the formation of HCN along the prompt-NO formation pathway, has been directly measured for the first time... PI Kiel ER