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研究了GA(没食子酸)-KBrO_3-H_2SO_4体系的诱导期τ、振荡周期T_2与反应物起始浓度的依赖关系,302K时的经验式为τ及T_2都随~CGA的增加而增长,这与B-Z反应中关于有机物的结论不同。用循环伏安法研究该体系的结果表明,GA在诱导期结束时就基本上都被氧化为中间物,GA并不象前人所认为的是维持振荡的物种,实际参与振荡的是由GA生成的物质。本文还研究了Fe(Phen)_3~(2+)对GA-KBrO_3-H_2SO_4体系振荡的影响,发现Br~-振荡行为随Fe(Phen)_3~(2+)的浓度而变。低~CFe(phen)_3~(2+)时,Br~-的振荡行为与GA-KBrO_3-H_2SO_4体系的基本相似,其特征是每个振荡周期内,Br~-振荡脉冲发生前是逐渐积累的。随着~CFe(phen)_3~(2+)的增大,Br~-出现另一特征的振荡行为,在每个振荡周期内,Br~-振荡脉冲发生前是逐渐减小。我们认为,GA-KBrO_3-H_2SO_4-Fe(Phen)_3~(2+)体系的振荡不能单一地用OKN机理加以解释,它可能是两套振荡机理耦合的振荡。
The dependence of the induction period τ and the oscillation period T_2 on the initial concentration of reactants in GA (gallic acid) -KBrO_3-H_2SO_4 system was studied. The empirical formula τ2 and T_2 at 302K both increased with increasing CGA BZ reaction on the conclusions of different organic matter. The results of cyclic voltammetry studies of this system showed that GA was essentially oxidized to an intermediate at the end of the induction period. GA did not, as previously thought, maintain oscillatory species. The actual oscillation involved was GA Generated material. The effect of Fe (Phen) _3 ~ (2+) on the oscillation of GA-KBrO_3-H_2SO_4 system was also studied. It is found that the Br_ - oscillation behavior changes with the concentration of Fe (Phen) __3 ~ (2+). The oscillation behavior of Br ~ - is similar to that of GA-KBrO_3-H_2SO_4 system at low ~ CFe (phen) _3 ~ (2+), and is characterized by the gradual accumulation of Br ~ - oscillation pulses in each oscillation period of. With the increase of ~ CFe (phen) _3 ~ (2+), another characteristic of Br ~ - oscillates. In each oscillation period, the Br ~ - oscillation pulse gradually decreases. In our opinion, the oscillation of the GA-KBrO_3-H_2SO_4-Fe (Phen) _3 ~ (2+) system can not be explained by the single OKN mechanism. It may be the oscillation of the coupled oscillation mechanism.