Optimization of the cadmium-reductor for the determination of nitrate with a carrier-free designed automated analyzer

• Main Authors: CLChiang, 江承濂
• Other Authors: 白書禎
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/32297087792028757337

碩士 === 國立臺灣大學 === 海洋研究所 === 91 === This dissertation is aimed to improve stability of the automated determination of nitrate in natural waters using the cadmium-reductor. The coating conditions were examined for three copper solutions, including copper sulphate, copper chloride and copper nitrate. It was found that the best result can be obtained by immersing the cadmium wire into a 0.1% w/v concentration for 20 seconds, and the efficiency can reach to a stable level within 3 minutes. Using a 150 cm coiled redactor, a carrier-free automated system was implemented. The detection limit of this novel system was lowered to a 0.03 µM level. The precision at 10 µM was found to be 0.3% for freshwater and 0.7% for seawater. The suitable working concentration range was 0-45 µM, and a throughput of 10-12 sample per hour has been achieved.