本文根据准曲线测定样品的原理,经过对过期二氧化氮标准溶液实验,论述了比色分析标准溶液过期后仍可继续使用的方法。该方法的应用解决了长期以来大量过期标准溶液废弃流失,变相浪费、损失和增加环境污染的问题,并使化验室试剂费用成本得以下降、国家物质资源得以节省。 In this paper, based on the principle of quasi-curve determination of samples, after expiration of nitrogen dioxide standard solution experiments, discusses the colorimetric analysis standard solution can continue to use after the expiration of the method. The application of this method solves the problems of waste disposal, disguised waste, loss and increase of environmental pollution of a large number of outdated standard solutions for a long time, as well as the cost of reagent cost in laboratories can be reduced and national material resources can be saved.