Initiator efficiency definition

The differences of the initial structure generation procedure will influence the quality of NMR structures, because of the initial structure dependency of the calculations. The ability to cross the potential barrier (i.e., conformational space exploration efficiency) definitely depends on the molecular dynamics conditions (typically simulation time). The conditions, however, are usually not validated, because of limitations by computational resources. The computing power required is linearly dependent on the simulation time, and thus has been a strong limitation of the calculations. Furthermore, temperature and steric repulsion weighing schedules as well as the force field will influence the structural quality. 

Definition of a method for obtaining samples for a source of kinetic data on this reactive extmsion must take several factors into account o Extremely small initiator to polymer ratios are involved, o The rate of dispersion of the initiator and the degree of dispersion obtained is likely itiq>ortant to both the homogeneity of the product and the efficiency of the initiator. 

Equation 27 can be numerically integrated along the conversion trajectory to obtain the Initiator concentration as function of time. Therefore, calculation of t, 6 and C together with the values of M, Rp, rw and rn from the equations In Table II allows the estimation of the ratios (ktc/kp1), (kx/kp) and the efficiency as functions of conversion. Figure 3 shows the efficiency as function of conversion. Figure 4 shows the variation of the rate constants and efficiencies normalized to their initial values. The values for the ratio (ktc/kpl)/(ktc/kpl)o reported by Hui (18) are also shown for comparison. From the definition of efficiency it is possible to derive an equation for the instantaneous loading of initiator fragments,... 

However, the foregoing observations cannot definitely be ascribed to triplet CH2 for the following reasons. Dilution of the reaction mixture with argon while maintaining constant total pressure leads to decreased deactivation efficiency, as pointed out by Frey, and therefore the loss of stereospecificity may result from geometric isomerization of the initial excited adducts rather than from a different mechanism of reaction of triplet methylene. 

The initial rate in the liquid phase reaction is zero-order in methanol, first-order in isobutene and about third-order in the sulphonic groups of the ion exchanger [365]. A comparison of catalysis by an ion exchanger and anhydrous p-toluenesulphonic acid indicated an efficiency of between 5 and 8, depending on temperature, according to the Hammett definition [366]. 

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