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

形成异常地的原因主要有成岩作、热作、生化作、构造作、及流体密度差异作等。

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法从粗钨酸钠溶液中脱除游离碱是经济可行的。