The complexation of Cr^3＋ with F^- undergoes a muhistep reversible process. An approach to research the involved equilibria and kinetics using suitable chemometrics methods to the online measured UV-Vis spectra is proposed. By investigating the equilibrium spectra of the complexes at different molar ratios of M to L（ metal to ligand） and 50 ℃, the result of Principal Component Analysis（PCA） shows that three complexes, ML, ML2 and ML3, can be formed under the research conditions. The spectrum of each complex was then analyzed and the accumulated equilibrium constants were calculated by applying Target Testing Factor Analysis（TITA）. Meanwhile, a reactive intermediate was observed before the formation of MLx during the specific kinetic study at 15℃. The equilibrium constant and spectrum of the intermediate as well as the rate constants were all resolved by using TTFA.
采用Borland C++ Builder 6.0可视化编程环境和基于面向对象的C++语言开发动力学模拟软件。该软件中对微分方程组的求解采用四阶龙格-库塔法。该软件适用于模拟各种化学动力学过程,用户可以根据不同情况设置复杂反应的任意步骤及其基元反应、相应反应速率常数及各物种的初始浓度和反应时间等。软件根据用户设定的参数自动计算出参与反应过程中各物种的浓度变化,同时提供Excel输出功能和绘图功能,可以直观地看到反应的动力学曲线。该软件不需要其他应用软件支持,可以在Windows 98/Me/2000/XP/2003下直接运行。程序涉及到的算法,需要较复杂的数据结构,程序采用C++语言提供的标准模板库,简化了程序设计并提高了运行效率。该软件模拟了一个包含平行-连串反应的化学动力学过程,运行速度较快,并得到精确的计算结果。
The electrochemical characteristics of multi-component phenolic pollutants, such as phenol （Ph）, hydroquinone （HQ） and 4-nitrophenol （4-NP）, were investigated on boron-doped diamond （BDD） film electrode by differential pulse voltammetry （DPV） technique. A simple and feasible platform was accordingly established for the direct and simultaneous determination of these three phenolic pollutants. Results showed that, Ph, HQ and 4-NP gave obvious oxidation peaks on BDD electrode at the potential of 1.24, 0.76 and 1.52 V, respectively. Each of them displayed good linear relationship between their oxidation peak currents and their corresponding concentrations in a rather wide range coexisting with one or two of the other phenolic pollutants. The detection limits of Ph, HQ and 4-NP were estimated to be as low as 1.82×10^-6, 1.67×10^-6 and 1.44×10^-6 mol·L^-1, respectively. Therefore, a promising direct and simultaneous electrochemical determination method of multi-component phenolic pollutants in wastewater samples was constructed successfully on BDD electrode with advantages being rapid, simple, convenient, sensitive, in situ and inexpensive.
