Characterization tests nitrogen containing compounds

To test our hypothesis that the generation of methyl radicals can enhance the reaction between CH4 and NOx compounds, we first examined NO reduction by CH4 over MgO and Li/MgO, which is the most characterized catalyst system for methane oxidative coupling. This study showed that Li/MgO catalysts as well as pure MgO are indeed active for NO reduction by CH4 and the activity continuously increased with temperature up to 953K. Both N2 and N2O as nitrogen-containing products were observed, and selectivity to N2 increased with temperature. N2 mass balances showed that litde or no NO2 formation occurred. Control experiments demonstrated that there was no reaction of either NO or CH4 in an empty quartz tube reactor with quartz wool inserted. Further experiments in the absence of CH4 showed that there was no direct NO decomposition over these catalysts, which implies that NO reduction can proceed only in the presence of gaseous CH4. 

The LMU Munich research group has also been looking at tetrazole-free nitrogen-rich compounds that contain oxidizing groups such as nitramine functionalities. In this context, the preparation and structural characterization of dinitrobiuret (DNB) (Fig. 31) was carried out [109,110]. The high chemical and thermal stability of DNB and the determined critical diameter of 6 mm for DNB (Figs. 32, 33) in the Koenen test (steel shell test) is comparable to the values reported for HMX (8 mm), RDX (8 mm), or PETN (6 mm) and prompted us to obtain the thermodynamic data and detonation pressures and velocities for DNB in a combined experimental and theoretical study. 

All compounds that behave as narcotic analgesics characterized by the usual criteria contain a basic nitrogen center that either forms parts of an alicyclic ring system, as in morphine and pethidine, or terminates an acyclic chain, as in methadone, etonitazene, and the enkephalins. Nonbasic compounds of high activity in antinociceptive tests invariably fail to satisfy criteria for narcotic analgesics, such as reversal of effects by naloxone or nalorphine or evidence of binding to opioid receptors recent examples are the barbiturate... 

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