Modeling macro-activity

Smith et al. [64] reviewed kinetics of the WGSR and proposed micro- and macro-kinetic models. The micro-kinetic method is based on the knowledge about the elementary steps that are involved in the reaction and its energetics. This method explores the detailed chemistry of the reaction. Using this method it is possible to estimate the smface coverage, reaction order and activation enthalpy. This method provides the accm-ate pathway and prediction of the reac-ti(Mi, but is computationally intensive. On the other hand, the empirical models are based on the experimental results and are typically expressed in the Arrhenius model and provide an easy and computationally lighter way to predict the rate of reactiOTi. 

Students in this group always worked simultaneously with the macro, sub-micro and symbolic levels. They did so trying to make the representation in one level be a support for the development of both a representation in another level and a plausible model that could explain the systems they observed. In Activity 3, when building... 

Some authors consider diffusion (a), (b) as consecutive processes, and assume the existence of colliding pairs [7-9]. Other models stress the importance of segmental diffusion of the active ends in a common volume of the two colliding macro molecules [10-12]. A common drawback of the mathematical models is the lack of a generally formulated expression for the effective diffusion coefficient of the active end in a coiling chain. Most models try to solve this difficulty by introducing suitable parameters with some physical meaning. 

In this model, the rate constant, k, is expressed as a function of the pre-exponential factor, the ideal gas constant, R, temperature, T, and the activation energy, E. However, the Arrhenius temperature model often falls short of explaining the physical behavior of foods, especially of macro-molecular solutions at the temperatures above T. A better description of the physical properties is offered by the Williams-Landel-Ferry (WLF) model, which is an expression relating the change of the property to the T -T difference [37,38]. That is. 

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