Nitrogen, chemical exchange between oxides

Preparation of 99.5% Nitrogen-15 by Chemical Exchange between Oxides of Nitrogen in a Solvent Carrier System... 

In the above equations n and N are the atom fractions of nitrogen-15 species in the gas phase and the liquid phase respectively c (moles/cc.), d (cm.2/sec.), b (cm.) for the gas phase are respectively the concentration of oxides of nitrogen, the diffusion coefficient, and the thickness of the boundary layer, while C, D, and B are the same quantities for the liquid phase k (cc./moles-sec.) is a rate constant for the exchange of oxides of nitrogen between the gas and liquid phase. The specific transfer rate kr (moles/sec.-cm. ) when multiplied by the interfacial area a (cm.2/cc.) in a 1 cm. length of column per cm. of cross-sectional area gives an interphase transfer rate fc a (moles/sec.-cc.). If chemical reaction is rate limiting, fc a will be determined by the first term of Equation 25, otherwise it will be determined by the diffusion terms. 

Saraceno, A. J., and C. F. Trivisonno (eds.) Uranium Isotope Separation by Chemical Exchange Reactions Between UF and UFj-Nitrogen Oxide, Report GAT-674, Feb. 4, 1972. 

Hydrogen isotope exchange at the nitrogen atom of A, A -dimethylanilinium ions is catalyzed by acid " and nitrosonium ion. The latter reaction has been studied at acidities for which the subsequent chemical reaction between NO and amines is much slower. The mechanism postulates the formation of a loose complex between NO" and the anilinium ion, followed by proton loss from the nitrogen. This process is related to the direct diazotization of some anilinium ions, and to the nitrous acid-catalyzed nitration and oxidation of the A, A -di-methylanilinium ion. 

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