【作者】 刘念；

【导师】 梁逸曾；

【作者基本信息】 中南大学 ， 化学， 2014， 硕士

【摘要】 相对其它检测方法而言,电化学分析方法具有快速、准确、检测限低、灵敏度高等特点,在食品药品分析领域具有广泛的意义。本文基于电化学分析技术的这些优点,着眼电化学伏安法数据挖掘以及便携式智能仪器的开发,以红茶绿茶为体系,探究了电化学电子舌技术实现茶叶分类以及铋膜修饰玻碳电极检测重金属等方面的内容,所作的主要工作如下：1)基于电化学技术实现红茶绿茶的分类,本文设计了一套金属氧化物(氧化锡、氧化锌、氧化钛、氧化铋)修饰电极,并对比了四种不同的金属氧化物修饰泡沫镍电极在系统中的分辨能力。以循环伏安法得到的数据矩阵作为输入信息,采用有监督(PCA)和无监督(SVM)的模式识别方法对样本进行了分类,得到的效果良好。2)通过铋膜电极结合方波溶出伏安法测定了铅、镉元素的含量。通过设计一系列的条件实验,讨论了富集参数和方波参数对金属离子测定的影响。在优化的实验条件下,作出了铅、镉含量的校准曲线。3)在以上电化学分析研究的基础上,着手研制开发了一种便携式重金属智能电化学分析仪。在硬件方面,本设计采用了优良的集成电路和电磁兼容性设计,系统误差小,性能优越；在软件方面,集成了先进的化学计量学算法,使得数据处理更加精确高效。最后,成功研制出该便携式重金属智能分析仪,对相关溶液体系进行了测量。最终,将电化学信号与化学计量学方法结合起来,从数学的角度深度挖掘了电化学信号中的含义,用软件性能取代部分硬件设施,能很好的促进便携式电化学智能分析仪以及电化学传感器的发展。更多还原

【Abstract】 Compared with other testing methods, the electrochemical analysis method is fast, accurate, and of high sensitivity, thus it has broad implications in the field of food analysis. Considering these advantages from electrochemical analysis methods, we focus on voltammetry data mining and the development of portable intelligent instruments. In this work, electrochemical methods are explored in tea classification and the detection of heavy metal contents, the main work is organized as follows:1) First, an electronic tongue was designed for classification of green and black teas, with multivariate data analysis of cyclic voltammogram of a homemade metallic oxide (SnO2, ZnO, TiO2, Bi2O3) modified nickel foam electrode. Several different combinations of sensors, were compared in their classification ability in this system. Using the electrochemical responses obtained from cyclic voltammetry as input information, supervised and unsupervised chemometric analysis methods, principal component analysis (PCA) was performed as the exploratory method and support vectors machine (SVM) as the classification method.2) Combining bismuth film electrode with square wave stripping voltammetry, the contents of lead and cadmium were detected. A series of experiments are designed to optimize conditions, and mainly the effects of enrichment parameters and square wave parameters were considered.3) On the basis of the above electrochemical analysis, a portable smart style heavy metal electrochemical analyzer was under research and development. In the terms of hardware, excellent design of integrated circuits and electromagnetic compatibility were adopted, thus to ensure the analyzer’s small systematic error and superior performance; On the software side, incorporated advanced chemometric algorithms were making data processing more accurate and efficient. Finally, the portable intelligent heavy metal analyzer was successfully made and applied to the related solution measurements.Finally, since chemometrics could definitely drag the mathematical meaning of electrochemical signals, part of the hardware performance could be replaced by software, thus there would be a good promotion of smart portable electrochemical analyzer and electrochemical sensors.更多还原