Pattern Selection in the Belousov−Zhabotinsky Reaction with the Addition of an Activating Reactant

Abstract

Using the ferroin-catalyzed Belosov-Zhabotinsky (BZ) reaction with the addition of an activating reactant in a reaction-diffusion system, we experimentally studied the competition between target waves and spiral waves when the system was in an oscillatory state. We found that when the period of background oscillation is smaller than that of spiral waves, target waves automatically appear in the reaction medium despite of the presence of spiral waves. The target waves compete with spiral waves and eventually win over the spirals, driving them out of the reaction medium. We also carried out numerical simulations using a modified Oregonator model. Our simulation results qualitatively agree with the experimental observations.

Intelligent image sensor based on probing the evolution of redox potentials distributed in reaction–diffusion medium

“…5 is the photograph of BZ membrane immediately after the projection of the input-image for 10 s. It is the initial state of the image evolution process in the BZ membrane. As shown from image (2) to image (7) in Fig. 5, the output-image becomes clearer and brighter, and its edges propagate outward slightly.…”

“…Moreover, in a photosensitive version of BZ reaction, the desired pattern of chemical waves can be obtained simply by projecting an image onto a thin layer of the light-sensitive reaction medium [6]. These features of the BZ reaction have made it a convenient model for the study of spiral waves and localized patterns and for modeling highly parallel computational devices, where each micro-volume of BZ medium can be regarded as a one-bit-processor [7][8][9][10][11][12][13]. There were a few attempts to explore potential use of BZ reaction-diffusion medium as highly parallel computing devices in the last two decades [6,14,15].…”

A Simple Feedback Control Approach for Output Modulation of Spatiotemporal Patterns in a Class of Tubular Reactors

“…We consider the ferrioncatalyzed BZ with the addition of methanol as an activating reactant. 27 A modified Oregonator model considering the reaction of methanol with sodium bromate and acid sulfuric was proposed by Zhang et al 27 The proposed model considers the following species: sodium bromate (A), malonic acid (B), methanol (M), H + form the sulfuric acid (H), bromous acid (U), and the oxidized catalyst (V). Methanol reacts with sodium bromate and sulfuric acid, with a rate constant of k m , producing bromous acid, which is the activator of BZ reaction system.…”

“…The model, 27 after a suitable rescaling, is written as eq 1 with the following values: q)), and f 2 (y(ξ,t),z(ξ,t)) = (y − z). Here, y is the dimensionless bromous acid (U), and z is the dimensionless oxidized catalyst (V).…”

Heterogeneity selected target waves and their competition: Outgoing or ingoing?

“…The existence of the great majority of target waves in practice is attributed to a local heterogeneity (e.g., a dust particle, gas bubble, etc.) that plays the role of a pacemaker [2,[6][7][8][9][10][11][12][13][14][15][16], while self-organized target waves are also found both in several models [17][18][19] and in the experiments [20]. Theoretical studies on the heterogeneity sustained target patterns have also been provided [21,22], which makes us understand better the mechanism underlying the formation of target waves.…”