农用复(合)肥料常以尿素、硝铵等为主要原料,经机械混合造粒生产。为准确测定复混肥中尿素含量,本文通过试验,建立了含尿素氮、铵态氮和硝态氮混合肥料中尿素氮测定方法——二乙酰一肟分光光度法和计算法。二乙酰一肟分光光度法回收率为94.8%~102.32%,相对误差为1.94%;计算法相对误差为2.37%,两种方法均满足产品测定误差要求。 Agricultural compound (co) fertilizer often urea, ammonium nitrate as the main raw material, granulated by mechanical mixing production. In order to accurately determine the urea content in the compound fertilizer, the urea nitrogen determination method - diacetyl-oxime spectrophotometry and the calculation method were established in the experiment, including urea nitrogen, ammonium nitrogen and nitrate nitrogen. The recoveries of diacetyloxime were 94.8% ~ 102.32%, the relative error was 1.94%. The relative error of the calculation method was 2.37%. Both methods met the requirements of product determination error.