We have constructed a small ferroin-catalyzed Belousov-Zhabotinsky reactor connected with a main reactor through continuous mass flow. When each reactor is in an independent oscillating state. the activation energy of the oscillation frequency differs considerably from each other, which enables us to investigate the oscillating state of the former under precise control of the latter through coupling strength and frequency difference. With increasing flow rate. both synchronized and intermittent oscillations appear according to the sign of the frequency difference. A precursor exists near the synchronization, while the transition from resting to oscillating state takes place in a timely manner for the intermittent oscillation. (C) 2004 Published by Elsevier B.V.