Coupling of erratic Belousov-Zhabotinsky oscillators observed by spectrophotometric measure.

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One reason for the current interest in oscillating reactions is the numerous periodic phenomena that occur in spatial and temporal control of processes, including phenomena in living organisms such as reactions catalyzed by enzymes and reactions across membranes. The study of the interaction of two or more oscillating systems is directly connected with biological problems and with spatial pattern formation. For this reason, the coupling of chemical oscillators has been the subject of a number of studies. Experiments have been carried out using batch reactors, as well as CSTR reactors.The simplest system in which the coupling can be studied is a single solution. The coupling that occurs inside the same solution is very interesting; as in a closed reactor, the different parts of the solution are obviously physically coupled. We used the Belousov-Zhabotinsky (BZ) reaction, a metal ion–catalyzed oxidation and bromination of an organic substrate, this being the most frequently used reaction for experiments in chemical oscillations. In unstirred batch reactors, diffusion and convection may be as important for a system’s dynamics as for its local kinetics. In particular, the coupling between a temporal oscillation and a spatial dishomogeneity may produce chaotic behavior. Epstein and Showalter recently dedicated a review to nonlinear chemical dynamics, which contains an exhaustive discussion on coupled systems.The phenomenon most frequently observed in coupled systems is the adaptation of the oscillators of one to the other so that the frequencies are rationally related. In this paper the coupling of the chaotic or regular oscillating phenomena that occurs in different parts of the same well-premixed oscillating solution and the effect of splitting the solution into two different portions are investigated. In order to avoid ions transport resistance phenomena and other complications that are present in electrical coupling experiments, we used the spectrophotometric method instead of the electrochemical method.