The Briggs–Rauscher reaction containing malonic acid may undergo a sudden transition from low (state I) to high iodide and iodine (state II) concentration states after a well-defined and strongly reproducible oscillatory period. This study clearly shows that even though the time-dependent behavior of the oscillatory state is reproducible, the time lag necessary for the appearance of the state I to state II transition after the system leaves the oscillatory state becomes irreproducible for an individual kinetic run. This crazy clock behavior of the state I to state II transition is identified by repeated experiments in which stirring rate is taken as a control parameter and all other parameters such as initial conditions, temperature, vessel surface, and the age of solution were kept constant. Surprisingly, a better stirring condition does not make the transition reproducible; it simply does not allow the transition to happen at all. The proposed mechanism, additional explanations, and proposals for this irreproducibility of state I to state II transition have been presented. Considering the fact that the number of crazy clock reactions is only a few, this study may contribute to a better understanding of fundaments of this phenomenon.

中文翻译：

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Briggs-Rauscher反应中低碘和高碘浓度状态的转变：有关疯狂时钟行为的证据

经过明确定义且可高度重现的振荡周期后，含有丙二酸的Briggs-Rauscher反应可能会突然从低（状态I）变为高碘和碘（状态II）浓度状态。这项研究清楚地表明，即使振荡状态的时间依赖性行为是可重现的，但对于系统而言，从单个振荡运行开始，从系统离开振荡状态到出现状态I到状态II过渡所必需的时间滞后也是不可重现的。状态I到状态II转换的这种疯狂的时钟行为是通过重复实验确定的，其中将搅拌速率作为控制参数，并将所有其他参数（例如初始条件，温度，容器表面和溶液的使用期限）保持恒定。出奇，更好的搅拌条件不能使过渡重现；它根本不允许过渡发生。已经提出了针对I状态向II状态过渡的不可复制性的机制，其他解释和建议。考虑到疯狂的时钟反应的数量很少，这一研究可能有助于更好地理解这种现象的基本原理。