化学分析室张积学、林克恭、吴济青等同志,苦战四昼夜,试验成功一种新的以容量法代替重量法的测定矽酸盐、碳酸盐和粘土中的氧化钙、氧化镁的方法。在试验过程中,解决了下面几个问题: 1.用EDTA测定CaO时,以紫脲酸铵为指示剂,终点突变不明显,当稀释10倍时终点才明显; Chemical Analysis Room Zhang Ji Xue, Lin Kegong, Wu Jiqing and other comrades, fighting hard four days and nights, a successful test of a new volumetric method instead of gravimetric method for the determination of silicate, carbonate and clay in the calcium oxide, magnesium oxide method. In the course of the experiment, the following problems were solved: 1. When CaO was determined by EDTA, the endpoint mutation was not obvious when ammonium oxalate was used as an indicator, and the end point was not obvious when diluted by 10 times.