基于镀铜镉柱海水中硝酸盐氮的检测技术的研究

镀铜镉柱还原——重氮偶氮染色法在检测海水领域具有重要的位置，算法的不断创新优化成为海水水质检测质量的的关键。本研究以硝酸钾作为标准溶液，海水作溶剂做相关实验，并且在实际海水检测应用中得到良好的效果。通过对实验原理的分析及实验过程的探究，确定了本研究的最佳还原与显色条件。并采用偏最小二乘法（partial least squares regression，PLS）算法模型对实验数据进行预处理，利用浊度对其进行补偿，最终得到硝酸盐氮的最优模型。经实验结果比对，该方法确定的检测系统线性范围宽、检出限低，符合海水的快速检测要求。在此基础上设计了一套在线自动检测装置，解决了海水在线、实时监测的难题。

Research for detection technology of nitrate nitrogen in seawater based on a copper-plated cadmium column

In this paper, the traditional method of Cu-Cd column reduction-Diazo staining is studied to fully understand the application of this method in nitrate nitrogen seawater detection. Potassium nitrate standard solution is used to replace seawater in relevant experiments, and good results have been obtained in the practical application of seawater nitrate nitrogen detection. On the basis of previously determined parameters, the optimal conditions for reduction and color rendering were determined through experiments. At a reduction pump speed of 20 r/min, column height of 10 cm, and a pH range of 8-9, the reduction efficiency reached more than 99%. The amount of added p-aminobenzoic acid was 1 mL, the reaction time was 80 s, the amount of added naphthalene ethylenediamine hydrochloride was 0.75 ml, and the color development time was 5 min. Moreover, the PLS algorithm model was established to preprocess the data and obtain the prediction model. Turbidity compensation was made to obtain the optimal model of total nitrogen. Under the above conditions, the method displayed a wide linear range, low detection limit, and high standard recovery. On this basis, an online automatic detection device is designed to solve the problem of online and real-time monitoring of seawater.