LASER-INDUCED FLUORESCENCE DETECTION OF THE NS RADICAL IN SULFUR AND NITROGEN DOPED METHANE FLAMES

The nitrogen sulfide radical, NS, has been observed for the first time in methane flames. Methane doped with H//2S and NH//3 was burned with oxygen, nitrous oxide, and air as oxidizers with equivalence ratios between 1. 2 and 2. 3. Laser-induced fluorescence (LIF) was used to detect the NS. Steady-state concentrations of NS were estimated from the LIF signal to be about 0. 1% of the added sulfur concentration, indicating that NS may be an important reactive intermediate in these flames. This radical is a direct interconnection between the NO//x and SO//x production mechanisms.