Stabilization rate constant

This effect is not due to deformation impact on hydroperoxide stability rate constants of thermal decomposition of hydroperoxide in PP are the same for both isotropic and deformed samples. Moreover, even at 20°C, when hydroperoxide is stable, its escape during radiation-induced oxidation sharply drops with the growth of X. 

Hase s trajectory value for the association rate constant, /cp of 1.04 cm- s maybe used in conjunction with the above Langevin value of the collisional stabilization rate constant to yield a unimolecular dissociation rate constant of 3.75 x 10 ° s and a lifetime of 27 ps. In each case, these values are in excellent agreement with the order of magnitude of lifetimes predicted by Hase s calculations for cr/CHjCl collisions at relative translational energies of 1 kcal mor , rotational temperatures of 300 K, and vibrational energies equal to the zero-point energy of the system. 

Therefore the derived expression for the stabilization rate constant is... 

It is easy to determine the high- and low-pressure limits of the stabilization rate constant. In the limit of high pressure,... 

This is the same result (and the same set of phenomena) as the high-pressure limit for the association reaction rate constant derived in Eq. 9.127. The high-pressure stabilization rate constant is independent of pressure, and simply equals the rate constant for the excitation reaction, ka. 

The collisional stabilization (de-activation) efficiency is assumed to be unity, which is consistent with the strong collision assumption. Thus the stabilization rate constant ks is equal to the hard-sphere rate constant kHS, and Eq. 10.120 becomes... 

Calculate the stabilization rate constant kstab and bimolecular product formation rate constant ftprod using QRRK theory, as specified below. 

Stabilizer Rate constant (K xIO /hr) Percentage increase in stability ... 

As the experiment is operating in the kinetic low-pressure regime, the decomposition rate constant can consequently be considered to be much larger than the stabilization rate constant term k fcs[He]. This leads to a simplified expression for the termolecular rate constant, which can be applied to the experimental conditions present in the ion trap experiment... 

One thus obtains the apparent rate constants k g and kg3 by evaluation of the rate constants for the elementary steps (k , kr> kjj, and kg) and using tables of the Kassel integral (13) to estimate the degree of fall-off (I) from the limiting high pressure rate constant, k. k can be taken to be the high pressure recombination rate constant kg is the collisional stabilization rate constant k and kjj are the unimolecular rate constants corresponding to N-N and N-H bond fission, respectively, of the collision complex. These decay rate constants were estimated from the RRK expression. 

A look at the equations (110) 113) clarifies this conclusion the apparent high-pressure rate constant for stabilization of A is obviously pressure independent and the high-pressure rate constant for product formation from A is inversely proportional to [M] (due to This is reasonable because product formation competes with collisional stabilization. The high-pressure stabilization rate constant for B formation ( stab,B) also depends inversely on [M] for the same reason and thus its dependence of [M] differs from Arstab hy [M] The same [M] difference is observed between AprodA and Apr dB, since latter high-pressure rate constant shows a quadratic inverse dependence on [M]. 

Within their low-pressure limits both stabilization rate constants depend linearly on [M] (incorporated in and 5,b), while the rate constants for product formation are both pressure independent under these conditions. 

At the high-pressure limit, the stabilization rate constant for C2H3O2 is equal to the total rate constant. 

Figure 3.8 Arrhenius diagram for stabilization rate constant k, for vitamin E ( ) and...

---