The method of preparing cobalt blue pigment in the liquid phase was studied by using urea as homogeneous precipitating agent.

研究了用尿素为均匀沉淀剂，在液相中制备钴蓝颜料的方法。

Method: Same mobile phase and detection wavelength were selected and suitable precipitating agent was used. The HPLC conditions were optimized.

方法：选择相同的流动相和检测波长，采用适当的沉淀剂，对四种添加剂的检测条件进行了优化。

This paper discusses the effects of sample resting when precipitating agent is added on experiment results by using EDTA volumetric method for the determination of SO 2- 4 in water.

对EDTA容量法测定水中硫酸根时，对加入沉淀剂后样品静置时间对测定结果的影响进行了研究。