Dividing Blobs, Chemical Flowers, and Patterned Islands in a Reaction−Diffusion System

In an one-side-fed open spatial reactor operated with the chlorine dioxide−iodine−malonic acid reaction in the presence of polyvinyl alcohol, we systematically studied the growth dynamics of Turing patterns after a supercritical parameter change. We describe different modes of propagation of the patterned state in an absolutely unstable uniform state, among which are a spot division and a finger splitting mode. We attribute these peculiar growth modes to the existence of two different uniform states and to a morphological instability of a propagating front linking these two states. In regions where bistability between the Turing state and a uniform state is obtained, the interface between the patterned state and the uniform state can be brought to a halt and thus localized patterned states are observed.