The reasons forming abnormal formation pressure mainly includes digenesis, thermogenesis, biochemical action, tectonic action, dialysis, and fluid density difference action.

形成常地层压的原因主要有成岩、热、生化、构造、渗析及流体密度等。

It has been proved that it is economical and feasible to eliminate educt alkali from coarse sodium tungstate with electrodialysis method of negative ion (1) selective membrane.

一价阴离子选择膜电渗析法从粗钨酸钠溶液中脱除游离碱是经济可行的。