Nitrogen monoxide, formation

C. At that temperature some endothermic reactions take place that at lower temperatures are not spontaneous under standard conditions (pure substances, each at I bar). Estimate the temperatures at which the following stratospheric reactions become spontaneous under standard conditions. Which ones could occur during re-entry of the space shuttle (a) The formation of nitrogen monoxide from nitrogen and oxygen ... 

Herold, S., Rock, G., Reactions of deoxy-, oxy-, and methemoglobin with nitrogen monoxide. Mechanistic studies of the S-nitrosothiol formation under different mixing conditions, /. Biol. Chem. 278 (2003), p. 6623-34... 

Two major fragmentation pathways have been observed in the mass spectrum of l,2,3-benzotriazin-4-one (10, R = H), and these are outlined in Scheme 1. The primary mode of cleavage (Path a) involves loss of nitrogen and formation of the y3-lactam (179), which undergoes further fragmentation as shown. Alternatively, loss of HCNO or HNj (Path b) leads to a diazonium ion or acylium radical ion which then decomposes to CjH by loss of nitrogen or carbon monoxide. The mass... 

Eriksson, P., and L.-G. Johansson, The Formation of Sulfuric Acid, Nitrogen Monoxide, and Nitrous Acid on Gold in Air Containing Sub-ppm Concentrations of S02 and N02, J. Electrochem. Soc., 138, f227-f233 (199f). 

Toumay, Murphy, Damon and Van Dolah [41] examined the fumes produced by the detonation of ammonium nitrate-fuel mixtures. They came to the conclusion that carbon monoxide formation is within the allowed limits. However, the concentration of nitric oxide and nitrogen dioxide is much higher than in typical dynamite compositions. On the ground of these experiments they expressed the view that ammonium nitrate-fuel compositions should not be recommended for underground blasting. 

In the following reaction sequence for the catalytic formation of ozone from molecular oxygen, which chemical compound is the catalyst nitrogen monoxide or nitrogen dioxide ... 

A profile of average urban concentrations of nitrogen monoxide, nitrogen dioxide, and ozone is given in Figure 17.12, which neatly shows how the formation of one is related to the formation of the other two. Early morning rush hour causes a... 

The synthesis of paratolunitrile (PTN) and terephtalonitrile (TPN) by reaction of paraxylene with nitrogen monoxide was studied over a series of aerogel chromium oxide alumina catalysts. The stabilization of the active phase was interpreted on the basis of Cr O support interactions. Kinetic studies show that the reaction follows a "redox" mechanism for the formation of PTN and a Langmuir Hinshelwood mechanism for the production of TPN. 

The results obtained corresponding to the consumption of paraxylene and the formation of PTN (see Figs. 3 and 4) are interpreted by a redox mechanism which implies a stationary state whith equality between the rates of the two steps of reduction of the catalyst by paraxylene and its oxidation by nitrogen monoxide (ref. 3). Table 3 gives the values of the rate constants of the two steps and shows that Kq and calculated for the consumption of paraxylene or the formation of paratolunitrile, the main product, are very similar in agreement with the redox mechanism. 

Finally, nitric acid is formed by the reaction of dissolved nitrogen peroxide with water (Reactions 5 and 6). The formation of two moles of acid is accompanied by the formation of one mole of nitrogen monoxide gas. This nitrogen monoxide must be recycled within the... 

As Barr et al. (2003) pointed out, the importance of such emissions is determined mainly by their impact on the three processes taking place in the atmosphere. The first consists in that such NMHCs as isoprene form in the course of carboxylization in plants and contribute much thereby to the formation of biospheric carbon cycle. The second process is connected with NMHCs exhibiting high chemical activity with respect to such main oxidants as hydroxyl radicals (OH), ozone (03), and nitrate radicals (N03). Reactions with the participation of such components result in the formation of radicals of alkylperoxides (R02), which favor efficient transformation of nitrogen monoxide (NO) into nitrogen dioxide (N02), which favors an increase of ozone concentration in the ABL. Finally, NMHC oxidation leads to the formation of such carbonyl compounds as formaldehyde (HCHO), which stimulates the processes of 03 formation. Finally, the oxidation of monoterpenes and sesquiterpenes results in the intensive formation of fine carbon aerosol with a particle diameter of <0.4 pm... 

The reaction of Ph2P(CH2)2SnCl3 with nitrogen monoxide in acetone or sulfur in dichloromethane results in the formation of pentacoordinated chelates, which can form dimeric hexacoordinated structures in the solid state (Equation 7) <2002JOM25>. 

The formation of nitrophenols and nitrobenzene by the photochemical reaction of benzene in the presence of nitrogen monoxide. Chemosphere 2 77-82. 

The mechanistic situation is complicated by the competing photolysis of nitrite, which results in the formation of nitrogen monoxide and oxide radical anions (Eq. 6-9). The latter are immediately protonated in water at pH <12 to yield hydroxide and hydroxyl radicals according to Eq. 6-8. 

Use of ceramic fiber burners with natural gas can result in reduced emissions of nitrogen oxide. Ceramic fiber burners can lead to a high radiative heat transfer and thus a lower flue gas temperature, which in turn results in lower nitrogen monoxide emission. The nitrogen oxide formation depends on the flue gas temperature in a more or less exponential manner. Thus, a reduced flue gas temperature results in a reduced NO, production. Ceramic fiber burners can thus lead to less NO, than conventional burners. 

Metal- and proton-exchanged zeolites have been recently attracted much attention because of their selective catalytic activity to efficiently reduce nitrogen monoxide (NO) by hydrocarbon in an 02-rich atmosphere [1]. The formation of nitrogen dioxide (NO2) from NO and O2 has been suggested as an important step in the selective reduction [2, 3] NO2 is one of rare stable paramagnetic gaseous molecules and has been subjected to electron spin resonance (ESR) studies [4-7]. The ESR parameters and their relation/to the electronic structure have been well established [4] and NO2 can be used as a "spin probe" for the study of molecular dynamics at the gas-solid interface by ESR. 

Table 2 Using the RADMASTE Molecular Stencil to represent the formation of nitrogen monoxide in the presence of a nitrogen oxygen molecular ratio of 4 1...

Nojima, K., K. Fukaya, S. Fukui and S. Kanno, The formation of nitrophenol and nitrobenzene by the photochemical reaction of benzene in the presence of nitrogen monoxide, Chemosphere, 2 (1975), 77-82. 

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