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

依据水质资料水源水质安全保障。

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

道德力的主要特质有: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.

运动中的黏表面与溶液电中介质形成的电动电位决定黏的流变学质和渗透质。