Department of Mathematical Sciences, Ibaraki University, Bunkyo, Mito 310-8512, Japan.
J Phys Chem A. 2010 Sep 23;114(37):10090-6. doi: 10.1021/jp106700f.
This study was aimed at identifying a quantitatively accurate reaction model of the bromate-sulfilte-ferrocyanide (BSF) pH oscillator by using the simulation-based model estimation algorithm known as the particle filter. The Rbai-Kaminaga-Hanazaki (RKH) model proposed for the BSF system was extended by adding the protonation equilibrium of SO42-, for which the particle filter analysis was carried out to optimize the rate constants involved with reference to the measured pH oscillation data. The extended RKH model with the optimized rate constants almost completely reproduced the measured pH oscillations and the state diagram, showing the validity of the present analysis. Chemical oscillators such as the BSF system show drastic switching of the dominant reaction path, which strongly disturbs the convergence of the rate constants if the objective function is defined in a conventional manner to reflect only a single time step datum. In this study, the objective function was defined as the residual sum of squares with respect to pH taken over an interval longer than one oscillatory period, so that all of the relevant reaction steps can contribute to the objective function. This is the first report which exemplifies the effectiveness of the particle filter in the analysis of real complex chemical systems.
本研究旨在通过使用基于模拟的模型估计算法（即粒子滤波器），确定溴酸盐-亚硫酸盐-亚铁氰化物（BSF）pH 振荡器的定量准确反应模型。针对 BSF 系统提出的 Rbai-Kaminaga-Hanazaki（RKH）模型通过添加 SO42-的质子化平衡进行了扩展，针对该模型进行了粒子滤波器分析，以参考测量的 pH 振荡数据来优化涉及的速率常数。具有优化速率常数的扩展 RKH 模型几乎完全再现了测量的 pH 振荡和状态图，表明了本分析的有效性。BSF 系统等化学振荡器表现出主导反应路径的剧烈切换，如果目标函数以传统方式定义以仅反映单个时间步数据，则会强烈干扰速率常数的收敛。在本研究中，目标函数定义为 pH 的残差平方和，该 pH 的残差平方和是在超过一个振荡周期的时间段上取的，从而使所有相关的反应步骤都可以对目标函数做出贡献。这是第一个例证说明了粒子滤波器在分析真实复杂化学系统中的有效性的报告。
