A Kinetic Study of the Reaction of NH 2 with NO in the Temperature Range 1400-2800 K. -The title reaction is found two proceed via the following two main reaction channels: NH 2 + NO → N 2 + H 2 O and NH 2 + NO → N 2 + OH + H. The first reaction channel clearly dominates the second one at temp. ¡1000 K, however, the contribution of the second channel increases from around 50% at 1500 K

The formation of NH2 and NH radicals as well as H and N atoms during the thermal decomposition of hydrazine was investigated over a wide temperature range. For the first time frequency-modulated spectroscopy was used for the detection of NHp radicals behind shock waves. In comparison with the dual beam laser absorption technique, the detection limit has been improved by one and a half orders of magnitude.For reaction (5a) NH2+M + NH+H+M the rate constants were obtained in the temperature range from 2200 to 4000 K ks,=(1.2+0.5)10's~exp [-(318* 10) kJ mol-'/RT] cm'lmol s and for reaction (6) N H c M --t N + H + M in the temperature range from 2500 to 3400 K k6=(l.8+0.8)10'4.exp [-(313? 15) kJ mol-'/RT] cm3/mol s.The experimental apparent activation energies were found to be in good agreement with theoretical calculations and recently recommended enthalpies of formation for NH2 and NH. The competing NH2 decomposition channel (5b) NHz+M -+ N+H2+M was shown to be of minor importance ( < 5%). The kinetic behavior of the unimolecular decomposition of NH2 is compared with that of H20 and k H 2 .

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In this work the processes of nonequilibrium radiation and ionization in the weak shock waves (2 < M < 4) in argon or helium, containing a small admixture (0.1–2%) of Fe(CO)5 are experimentally studied. The spectra- and time-resolved measurements, performed using a ICCD camera (StreakStar II, LaVision GmbH) have shown, that the unresolved radiation spectra are situated in the range 400–700 nm. The maximum of the spectra lies approximately at 615 nm. The radiation appeared immediately at the propagating shock front and lasted about 8–12 μs. The following time-resolved measurements, performed using photomultipliers (at 615 ± 10 nm) and calibrated electric probes have shown intensive peaks of emission and electric current with duration of few μs, that correlates with the characteristic time of active growth of iron clusters. The analysis of the results obtained allowed to conclude that the real mechanism of generation of the observed peaks of radiation and ionization is the instant dissociation of Fe(CO)5 causing an active condensation process of a supersaturated vapor of iron atoms, which results in the formation of excited and ionized iron clusters.

The formation of carbon particles following the pyrolysis of C