摘要：

根据国家标准GB11894—1989测定地表水中的总氮时，发现了空白实验的吸光度异常偏高的现象。由于实验过程中，氧化剂的纯度、氧化溶液的放置时间、氧化时间的长短、蒸馏水的纯度、检测仪器的稳定性及实验环境等因素都会对空白实验的吸光度产生影响，因此，通过一系列对比实验，系统地检查了实验用水、试剂、器皿、全自动高压灭菌器和紫外可见分光光度计，对可能的影响因素逐一进行了分析和排除，找到了实验出现问题的原因，并进行了校正。

关键词: 总氮, 空白实验, 吸光度

Abstract:

According to GB 11894-1989, when the concentration of the total nitrogen in surface water is determined, the absorbance of the blank test is rather high. During the tests, the factors, such as the purity of oxidant, the deposited time of oxidation solution, the stability of experimental apparatus, the purity of distilled water, experi-mental environment, etc. bring negative influences on the experimental results. Through a series of contrast tests, the water in the tests, reagent, vessels, autoclave and ultraviolet visible spectrophotometry which have influences on the tests have been examined systematically one by one. The main causes for problems have been found out and adjustments have been made.

Key words: total nitrogen, blank test, absorbance

中图分类号: 

• X832