10.1021/acs.jpca.9b09642.s001 Ling Yuan Ling Yuan Zhuoxuan Li Zhuoxuan Li Mengfei Liu Mengfei Liu Xiaoli Lv Xiaoli Lv Qingyu Gao Qingyu Gao Modulation Effects of Permanganate and Manganese(II) Ions on the Oscillatory Dynamics in a Bromate–Sulfite Reaction System American Chemical Society 2020 pH oscillations pH feedback process study nonlinear temperature oscillations flow rate modulation effects Oscillatory Dynamics feedback loop period length change unmonotonically oscillatory dynamics nonmonotonic change Modulation Effects feedback agent permanganate concentration Large-amplitude temperature oscillations 2020-01-13 22:29:27 Journal contribution https://acs.figshare.com/articles/journal_contribution/Modulation_Effects_of_Permanganate_and_Manganese_II_Ions_on_the_Oscillatory_Dynamics_in_a_Bromate_Sulfite_Reaction_System/11594784 It is important to study nonlinear dynamical systems showing pH and temperature oscillations simultaneously. Here, we systematically investigated the bromate–sulfite reaction in its coupled system. Large-amplitude temperature oscillations could be measured accompanied by the pH oscillations with or without permanganate and manganese­(II) ions. The modulation effects on the oscillatory dynamics of the bromate–sulfite reaction system produced by permanganate and manganese­(II) ions were investigated in detail. On the one hand, with permanganate, an additional negative pH feedback process between permanganate and bisulfite occurs, leading to weakening the pH positive feedback. The above opposite effects make the period length change unmonotonically when adjusting the permanganate concentration and flow rate. On the other hand, with Mn<sup>2+</sup> as the feedback agent, the nonmonotonic change of period was not obvious because it only contained one feedback loop, which can only reinforce negative feedback without affecting positive feedback.