中文摘要：

以NH4HCO3与MgSO4·7H2O为反应物料,采用低温液相法合成了放射状三水碳酸镁晶体,采用XRD,SEM、FTIR对合成的试样进行了测试表征,重点讨论了NH4HCO3反应初始浓度及不同反应时间对晶体结晶形貌的影响。研究结果表明：当NH4HCO3的反应初始浓度为0.2~0.5 mol/L,反应初始浓度越小,越有利于放射状晶体的结晶生长。反应体系中Mg（NH3）2＋y络合物的形成成为放射状晶体形成的主要原因。在此基础上,探讨了放射状晶体的结晶生长机理。

英文摘要：

The radial nesquehonite crystal was synthesized by low-temperature liquid phase method using NH4HCO3and MgSO4·7H2O as raw materials. The products were characterized by XRD,SEM and FTIR,and the effect of NH4HCO3initial concentration and reaction time on the morphlogy were studied. The results show that when the initial reaction concentration of NH4HCO3is 0. 2-0. 5 mol / L,the lower of the initial reaction concentration was more benefit for the crystallization growth of radial crystals. It was the main reason for radial crystal formation that the complexformation of Mg（NH3）2 ＋ y. On this basis,the crystallization growth mechanism of radial crystal was discussed.