An amplified Oregonator model simulating alternative excitabilities, transitions in types of oscillations, and temporary bistability in a closed system.

The original Oregonator model of five irreversible steps and one stoichiometric parameter has been amplified to seven irreversible steps. The amplified model simulates excitability of a reduced steady state induced by silver ions and of an oxidized steady state induced by bromide ions. It also simulates how oscillations during a single run might change from reduction pulses to oxidation pulses. Finally, it simulates a temporary bistability persisting for over two hours in a closed system. If independent measurements determine the rate of enolization of the organic substrate and the rate of reaction of that substrate with the oxidized form of the catalyst, this model may be able to simulate semiquantitatively a large fraction of reported behaviors of catalyzed homogeneous Belousov–Zhabotinsky systems. It will not model systems in which Br2 accumulates or in which there are high-frequency small-amplitude oscillations around an oxidized steady state. Procedures are suggested for simulating such behaviors. [ABSTRACT FROM AUTHOR]