方法基于 N_(263)—甲基三烷基氯化胺与间胺基黄形成1:1的稳定有色化合物。用氯仿萃取可与干扰离子分离,直接于有机相中比色测定。一、主要试剂:N_(263)标准溶液:1毫克/毫升。(溶剂为10%二乙基已醇,90%(?)化煤油)。取用时用微量取样器吸取。混合缓冲溶液:63.03克氯乙酸及243克柠檬酸溶解于500毫升水中,加12N 氨水61.4毫升,用水稀释至1400毫升。二、操作步骤; The method is based on the formation of a 1: 1 stable colored compound with N - (263) - methyltrialkylammonium chloride and m - aminopyridine. Extraction with chloroform can be separated from interfering ions, directly in the organic phase colorimetric determination. First, the main reagent: N_ (263) standard solution: 1 mg / ml. (Solvent is 10% diethylhexanol, 90% (?) Kerosene). Take when using micro-sampler suction. Mixed Buffer Solution: 63.03 g of chloroacetic acid and 243 g of citric acid were dissolved in 500 ml of water, 61.4 ml of 12N aqueous ammonia and diluted to 1400 ml with water. Second, the operation steps;