The special connections ensure that the system has excellent air tightness. 特別的連接方式保證了系統優(yōu)良的氣密性。
Dormancy for hard seeds is caused by impermeability to water and gas and mechanical constraint of the seed coat. 硬實(shí)種子種皮透水透氣性差和對胚生長(cháng)的機械限制，引起種子休眠。
Hollow fiber membranes with good gas permeability can be obtained after the extraction of the paraffin oil and stretching to a small extension. 將石蠟油提取掉后稍加拉伸即可得到透氣性很好的微孔中空纖維滲透膜。
