Autowaves in non-equilibrium extended systems

According to the classification [5], the spatial structures existing in homogeneous active (in particular, chemical) media are as follows  

Switch-like wave motion (fire spreading)  

Of special interest is the so-called Belousov-Zhabotinsky class of similar reactions [4,6-12], This system can serve as an extremely successful example of self-organisation proper mixing of several liquids in a given proportion and at certain temperature demonstrates practically all kinds of the autowave processes just mentioned. 

Numerous versions of the Belousov-Zhabotinsky system differ by chemical compounds used. The typical reaction involves oxidation of some organic compound by bromate ion (BrOj ) occurring in acid medium with metal catalyst (Ce , Mn , as well as complexes of Fe , Ru ). As an example, a particular reaction [4] could be mentioned, where an organic reductor is malonic acid CH2(COOH)2 and Ce + ions serve as a catalyst. In this reaction a solution changes periodically its colour due to oscillations in Ce concentration. Generally speaking, the reaction consists of two stages. At the first one metal is oxidized 

Despite the fact that from a principal point of view a problem of concentration oscillations could be considered as solved [4], satisfactory theoretical descriptions of experimentally well-studied particular reactions are practically absent. Due to very complicated reaction mechanism (in order to describe the Belousov-Zhabotinsky reaction even in terms of standard chemical kinetics several tens of concentration equations for intermediate products should be written down and solved numerically [4, 9,10]) these equations contain large number of ill-defined parameters - reaction rates [10]. 

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