水质.使用小型密封管测定水中总结合氮（ST-TNb）.第2部分：变色酸显色反应

[中文适用范围]： 本文件规定了测定各种来源水中总结合氮（ST-TNb）的方法：地下水、地表水和废水，浓度测量范围通常为 0.5 mg/l 至 150 mg/l ST-TNb采用小规模密封管法。 小型密封管方法可能需要不同的测量范围。 根据不同制造商的小型密封管方法的类型，测量范围可能有所不同。 用户可以选择适合应用范围的小规模密封管测试，或者通过初步稀释来调整浓度超过测试测量范围的样品。 注：小规模密封管测试的结果在测试应用范围的中间最为精确。 所有小规模密封管方法均基于在 100 °C 加热块中加热碱性过硫酸钾氧化，并且适用不同的消解时间。 根据所使用的小型密封管的典型操作程序，应用显色显色反应，参见第 9 条。 [外文原描述]： This document specifies a method for the determination of total bound nitrogen (ST-TN b ) in water of various origins: groundwater, surface water and wastewater, in a measuring range of concentration generally between 0,5 mg/l and 150 mg/l of ST-TN b using the small-scale sealed tube method. Different measuring ranges of small-scale sealed tube methods can be required. The measuring ranges can vary depending on the type of small-scale sealed tube method of different manufacturers. It is up to the user to choose the small-scale sealed tube test with the appropriate application range or to adapt samples with concentrations exceeding the measuring range of a test by preliminary dilution. NOTE The results of a small-scale sealed tube test are most precise in the middle of the application range of the test. All small-scale sealed tube methods are based on a heated alkaline potassium persulfate oxidation in a heating block at 100 °C and different digestion times are applicable. Chromotropic colour reaction is applied, depending on the typical operating procedure of the small-scale sealed tube used, see Clause 9 .