Two oscillatory Belousov-Zhabotinsky reactions are serially mass coupled to generate additional periodic states, period doubling, phase locking, quasiperiodicity, and chaos. The time series for these states are characterized in terms of their power spectra, attractors (reconstructed by singular value decomposition), Poincare sections, return maps, Lyapunov exponents, and various dimensionalities (Dq spectra). Adding trace impurities to the system does not alter the observed chaos. Model calculations using a partially reversible Oregonator model qualitatively agree with the experimental findings for the coupled oscillators.

Experimental studies of the oscillatory chlorite oxidation of thiocyanate carried out in a continuous-flow stirred tank reactor reveal chemical chaos arising from a period-doubling route. Analysis of the observed aperiodicity in terms of time series, Fourier spectra, reconstructed attractors, Poincarb sections, return maps, and generalized Renyi dimensions confirms the deterministic nature of the chaotic behavior in this system. Under different experimental conditions, complex periodic states consisting of various combinations of large-and small-amplitude oscillations are observed, and aperiodic states intervene the complex periodic regions. Diversity in the aperiodic behaviors found in the chlorite-sulfur subfamily of chemical oscillators is discussed in a comparison of its chaotic constitutents.

The output redox potential of the chemical oscillations of the Belousov-Zhabotinskii (BZ) reaction was wed as the input for the flow rate with a built-in time delay between output and input. A variety of periodic states were observed when the time delay and the coupling strength were increased. Chaotic states are produced by delayed feedback which are normally not observed in the free-running oscillator at the same residence time, A BZ model containing at least two cycles is supported by the delay experiments: the BZ-limit cycle and the inflow cycle. All states are analyzed and characterized in terms of their power spectra, attractors (reconstructed by singular value decomposition), PoincarC sections, return maps, Lyapunov exponents, and the generalized Renyi dimensions.

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