EXPERIMENTAL STABILIZATION OF UNSTABLE STEADY-STATES IN OSCILLATORY AND EXCITABLE REACTION SYSTEMS

A feedback method is used to stabilize unstable stationary states in e xperiments with the chlorite-iodide reaction. The unstable stationary states occur in oscillatory and excitable regions of constraint space. Stabilization of unstable steady states provides information about th ese states and may be of practical importance. An analytical study of a model mechanism of this reaction is consistent with the experiments. This feedback method does not create new stationary states but stabil izes unstable stationary states present in the autonomous system. Unli ke ''thermostat'' type methods, knowledge of the exact location of the unstable stationary states of the autonomous system is not required t o implement this feedback method.