Filter bed should be exposurd as less as possible because alternation of exposure and immersion is disbennifit to the penetrability of filter bed.

依资料分析了源安全保障。

Its existence is due to its peculiar traits, among which the most important ones are particular autorhythmicity, self coerciveness, universal penetrability and lofty ideality.

道德力的主要特有:独特自律、自我强制、普遍渗透和崇高理想。

Argillaceous rheological property and penetrability of clay have been decided by zeta-potential,which is conducted by the mobile surface of clay particle and electroneutrality media of solution.

运动中的黏土颗粒表面电中介形成的电动电位决定了黏土的流变学和渗透。