It is shown that expansible ettringite forms in the topochemical reaction,and crystallizes in-situ on the surface of unhydrated aluminate minerals and orients radially.

发现能够产生的钙矾石是由学反应所生成；它们在未水的铝酸盐物表面原地结晶，呈放射状生长。

The expansion mechanism of hydroxide expanding phase for oil well cement slurry are discussed on the basis of principle of chemical thermodynamics and topochemical reaction model.

要基于原地反应模型和学热力学原理，讨论了晶体生长压的源动力及水泥浆体体积与结晶压的关系。