基于SC-GD耦合滤光分选系统检测水体金属离子的研究

发布时间：2018-04-09 16:10

本文选题：溶液阴极放电　切入点：滤光分选　出处：《重庆邮电大学》2016年硕士论文

【摘要】：随着现代工农业的飞速发展,水体污染越来越严重。因此,研究一种高效低成本的水中金属离子检测方法来实现对环境和食品安全等领域的水中金属离子的检测是很有必要的。目前,传统的水中金属离子检测方法主要包括两大类,一类是以电化学原理为基础的检测方法,此方法在稳定性和选择性方面存在一些不足,另一类是以光谱质谱技术为原理的检测方法,该方法的缺点是设备体积大,检测成本偏高,不能很好的满足便捷检测及设备小型化的检测要求。溶液阴极辉光放电发射光谱检测金属是近几年得到国内外普遍关注的一种高效的水中金属离子检测方法,但是目前光谱检测部分均采用光谱仪进行采集和处理,使得整套检测装置的便捷性降低,成本增加。为了解决这些问题,本论文尝试研究了一种基于溶液阴极辉光放电发射光谱技术与滤光分选技术相结合的一种水中金属离子检测方法,设计并完成了一套新型的水中金属离子光电检测装置。该检测装置包括溶液阴极辉光放电光源产生部分、滤光分选部分以及数据采集部分,光源产生装置以金属钨棒为阳极,溶液从玻璃毛细管流出并作为放电阴极,通过对两极施加高压产生放电等离子体。滤光分选部分由石英透镜、可调狭缝和滤光片轮组成,数据采集部分由光电倍增管和皮安表构成。文章首先在理论上阐述了基于溶液阴极辉光放电耦合滤光分选系统的工作原理,之后搭建了溶液阴极辉光放电光源装置,利用滤光分选部分实现了特征光谱信号的选取和收集,并通过数据采集部分对信号进行采集和处理,最后对整个检测系统进行测试,优化实验条件,研究不同元素原子谱线强度的垂直分布,在此基础上对Na、K、Ca、Li、Sr、Rb和Cs七种金属元素标准溶液进行了检测,得到的检出限分别为0.0007mg/L、0.0028mg/L、0.4240mg/L、0.0042mg/L、2.1000mg/L、0.0044mg/L和0.0595mg/L。通过基质效应实验发现,高Na环境对K的信号强度具有抑制作用,并且当Na浓度达到一定值时,抑制作用趋于饱和,最后利用此特性检测并得到了生理盐水中K元素的含量为0.534mg/L。与常见的检测方法相比,溶液阴极辉光放电耦合滤光分选装置体积更小,检测成本更低,而且兼具了可在线连续检测和低检出限的特点,使得该检测技术更适合水中金属元素的检测。
[Abstract]:With the rapid development of modern industry and agriculture, water pollution is becoming more and more serious.Therefore, it is necessary to study a high efficiency and low cost method to detect metal ions in water in the field of environment and food safety.At present, the traditional detection methods of metal ions in water mainly include two categories, one is based on electrochemical principle, this method has some shortcomings in stability and selectivity.The other is the detection method based on spectrum mass spectrometry. The disadvantages of this method are the large size of the equipment and the high detection cost, which can not meet the requirements of convenient detection and miniaturization of the equipment.Solution cathodic glow discharge emission spectrometry is a highly effective method for metal ion detection in water, which has received widespread attention in recent years. However, at present, spectrometer is used to collect and process metal ions in water.The convenience of the whole detection device is reduced and the cost is increased.In order to solve these problems, this paper attempts to study a method of metal ion detection in water based on the combination of cathodic glow discharge emission spectroscopy and filter separation.A new photoelectric detection device for metal ions in water is designed and completed.The detecting device includes a solution cathode glow discharge light source generation section, a filter light sorting section and a data acquisition section. The light source generating apparatus uses a metal tungsten rod as the anode, the solution flows out from the glass capillary and acts as the discharge cathode.Discharge plasma is produced by applying high voltage to the two poles.The filter sorting part is composed of quartz lens, adjustable slit and filter wheel, and the data acquisition part is composed of photomultiplier tube and picoammeter.In this paper, the working principle of the solution cathodic glow discharge coupling filter sorting system is described in theory, and then a solution cathode glow discharge light source device is built, and the characteristic spectral signal is selected and collected by the filter sorting part.The signal is collected and processed through the data acquisition part. Finally, the whole detection system is tested, the experimental conditions are optimized, and the vertical distribution of the atomic spectral line intensity of different elements is studied.Through the matrix effect experiment, it was found that the signal intensity of K was inhibited in high Na environment, and when Na concentration reached a certain value, the inhibitory effect tended to saturation. Finally, the content of K element in normal saline was determined and obtained to be 0.534 mg / L by using this characteristic.Compared with the common detection methods, the solution cathodic glow discharge coupled filter separator is smaller in size, lower in detection cost, and has the characteristics of on-line continuous detection and low detection limit.The detection technology is more suitable for the detection of metal elements in water.
【学位授予单位】：重庆邮电大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：X832

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