The two major themes in this project involve transport in disordered media and the development of models for reaction kinetics in chemistry. In addition to work on these, some time was spent on the calculation of the dependence of the relaxation time for the transition from elastic viscosity to plastic viscosity behavior of a polymer on the molecular weight. Together with S. Havlin and R. Kopelman we have investigated the spatial distribution of reactants in one and three dimensions. In one dimension the kinetic properties do not follow classical laws while in three dimensions they do. We show that these effects are due in part to the non-Poisson spatial distribution of reactants in one dimension. Measurements of the dependence of the relaxation time polymer viscosity on the molecular weight deviate from the theoretical prediction that such dependence should go as the inverse third power. Experiments are consistent with the dependence on a power that ranges between -3.3 and -4. Together with J. Bendler, M. Dishon, and H. Kesten we have produced a physical model in which the indicated power is -10/3 which is in much better agreement with the experimental data than earlier theoretical work.
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