Direct Detection of NO Produced by High-Temperature Surface-Catalyzed Atom Recombination

c = concentration or molar density, molm 3 D = diffusion coefficient, m s 1 E = activation energy, Jmol 1 fs;r = branching fraction of reactant s into product r j = diffusive mass flux, kgm 2 s 1 ki = rate coefficient for reaction i, cm molecule 1 s 1 or cm molecule 2 s 2 L = sidearm length, m M = molar mass, kgmol 1 P = pressure, Pa R = sidearm radius, m R = universal gas constant, 8:314 Jmol 1 K 1 r = radial sidearm coordinate, m T = temperature, K v = average thermal speed, ms 1 w = gas-phase production rate, kgm 3 s 1 ww = surface production rate, kgm 2 s 1 x = mole fraction z = axial sidearm coordinate, m = loss probability = mass density, kgm 3 = diffusion velocity, ms 1 Subscripts