If the rate of interphase exchange is comparable with the rates of the reactions and decay of excited molecules, one can use equation similar to Eq. (54), taking into account the value of the coefficient d, which determines the average excess of the concentration C in a micelle during the lifetime of the excited species [Pg.220]

The rate coefficient km would contain factors for the thermal accommodation of a molecule in collision with the filament, the geometry of the filament and the trap, and the efficiency of capture of thermally excited molecules by the trap. The observed fall in pressure in a static atomisation reaction, occurring at the rate ua = kaP21/2 for a given filament temperature, would then be [Pg.195]

Here [A] is the concentration of A. and t refers to time. 8ki (E) is a differential rate coefficient for the reaction in which a molecule is excited to an energy between E and E + 8E. Thus, Equation 14.5 is the equation for the rate of appearance of A molecules with energy between E and E + 8E. [Pg.428]

In the literature there are several, mostly just slightly different, equations that describe the rate coefficient of the diffusion controlled reactions these equations are usually based on the solutions of Pick II diffusion law assuming that the reaction probability at contact distance is 1. Andre et al. [131] used the following equation to describe the time dependence of excited molecule concentration [RH ] produced by an infinite excitation pulse [Pg.386]

Case la. Reactions occur completely in the micellar phase (the exit rate constant for out lAo ) interphase exchange by product C is much faster than the reactions and decay of excited molecules (exit rate constant for C /c"ut kout lAo )- The stationary concentration [C] of the product is equal to its equilibrium concentration in the micellar phase, which is determined by its overall concentration [C] in the solution, its distribution coefficient q" and the volume concentration of the micellar phase X [Pg.219]

Ion-molecule association reactions and the collisional deactivation of excited ions have been the subjects of recent reviews.244-246 Several systematic studies have been performed in which the relative deactivating efficiencies of various Mf species have been determined. By applying the usual kinetic formulations for the generalized reaction scheme of equation (11.31), and assuming steady-state conditions for (AB+), an expression for the low-pressure third-order rate coefficient can be derived [Pg.150]

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