Control of chemical chaos through medium viscosity in a batch ferroin-catalysed Belousov–Zhabotinsky reaction

Abstract

In this paper we show that the active interplay of nonlinear kinetics and transport phenomena in a chemical oscillator can be exploited to induce and control chaos. To this aim we use as a model system the ferroin-catalysed Belousov-Zhabotinsky (BZ) oscillating reaction, which is known to evolve to characteristic chaotic transient dynamics when carried out under batch and unstirred conditions. In particular, chemical chaos was found to appear and disappear by following a Ruelle-Takens-Newhouse (RTN) scenario. Here we use medium viscosity as a bifurcation parameter to tune the reaction-diffusion-convection (RDC) interplay and force the reaction in a specific sequence of dynamical regimes: either (i) periodic → quasi-periodic → chaotic or (ii) periodic → quasi-periodic or (iii) only periodic. The medium viscosity can be set by adding different amounts of surfactant (sodium dodecyl sulphate), known to have a little impact on the reaction mechanism, above its critical micelle concentration. Experimental results are supported by means of numerical simulations of a RDC model, which combines self-sustained oscillations to the related chemically-induced buoyancy convection.

A New Image Encryption Algorithm Based on Composite Chaos and Hyperchaos Combined with DNA Coding

“…The Qi hyperchaotic system is a four-dimensional hyperchaotic system. The dynamic equation is shown as formula (4) as follows: (4) When the system parameters a = 50, b = 4, c = 13, d = 20, e = 4, the system is in a hyperchaotic state. When the initial value [1; 2; 3; 4] is selected, its attractor phase diagram develops as shown in Figure 4.…”

“…Due to its high sensitivity to initial values and system parameters, excellent ergodicity, and good pseudo-randomicity, chaotic systems have become the primary choice of cryptographic systems [3,4]. Therefore, many image encryption schemes based on chaos have been proposed [5,6].…”

Hofmeister Effect in Self-Organized Chemical Systems

“…To further support this view, new experiments with other redox catalysts are in progress. In particular, the isolation of specific ion effects in the ferroin-catalyzed BZ system would open new perspectives to study this phenomenon in pattern formation in spatially extended systems and more complex dynamics such as spatiotemporal chaos …”

Visualizing the Template of a Chaotic Attractor

“…Resulting of theoretical studies on chaos attractors, applications including chaotic dynamics can be found in a multitude of domains. Their range goes from computer science [23], through classical sciences with physical networks [14], biology and genetics [27] and chemistry with chaotic dynamics in chemical reactions [8], all the way to electronics and chaos in electronic devices [13] and even environmental studies on population evolution [5].…”