| The non-classical kinetics of elementary reactions in some basic diffusion-limited systems are studied in this thesis. Two reaction types are explored in detail: (1) Trapping reaction A + T → T and (2) elementary bimolecular reaction A + B → C. Different methods are used in both systems: experiments, Monte Carlo simulations, exact enumeration, and analytical theory. Experimentally the trapping reaction A + T → T was realized by photobleaching fluorescein molecules in solution by a focused laser beam. By changing the shape of the reactor and the laser beam, different dimensionalities are achieved: line trap in gaps between glass slides (1D behavior), point traps in gaps in-between glass slides (2D behavior), point trap in a flat rectangular capillary (2D to 1D behavior) and short line trap in a flat rectangular capillary (1D to 2D to 1D behavior). Reaction front kinetics of the bimolecular reaction A + B → C was discussed in quasi-1D confined systems. An experimental manifestation was the reaction between calcium ions and Calcium-Green-1 (Dextran attached) dye molecules, initially separated by a semi-permeable membrane. The experimental and theoretical approaches agree well with each other. The results show that non-classical kinetics in diffusion-limited systems differ from classical kinetics in two main aspects: an overall slowing down of the reaction rate with time and a dependency of the rate law on the dimensionality of the systems. |
