Direct measurements of the total rate constant of the reaction NCN + H and implications for the product branching ratio and the enthalpy of formation of NCN.

The overall rate constant of the reaction (2), NCN + H, which plays a key role in prompt-NO formation in flames, has been directly measured at temperatures 962 K < T < 2425 K behind shock waves. NCN radicals and H atoms were generated by the thermal decomposition of NCN3 and C2H5I, respectively. NCN concentration-time profiles were measured by sensitive narrow-line-width laser absorption at a wavelength of λ = 329.

Direct measurements of the high temperature rate constants of the reactions NCN + O, NCN + NCN, and NCN + M.

The rate constant of the reaction NCN + O has been directly measured for the first time. According to the revised Fenimore mechanism, which is initiated by the NCN forming reaction CH + N(2)→ NCN + H, this reaction plays a key role for prompt NO(x) formation in flames. NCN radicals and O atoms have been quantitatively generated by the pyrolysis of NCN(3) and N(2)O, respectively.

HCO formation in the thermal unimolecular decomposition of glyoxal: rotational and weak collision effects.

The multi-channel thermal unimolecular decomposition of glyoxal was experimentally investigated in the temperature range 1106 K < T < 2320 K and at total densities of 1.7 x 10(-6) mol cm(-3) < rho < 1.9 x 10(-5) mol cm(-3) by monitoring HCO (frequency modulation spectroscopy, FMS), (CHO)(2) (UV absorption), and H atom (atom resonance absorption spectroscopy, H-ARAS) concentration-time profiles behind shock waves.