减压过滤

土壤中乙草胺用甲醇提取，提取液经减压过滤，浓缩，石油醚定容用GC-ECD测定。

Acetochlor in soil was extracted by methanol , with pressure reduction and pressure filtration and constant volume of petroleum ether , and was subjected to gas chromatography with ECD .

水稻植株、稻米中乙草胺用二氯甲烷提取，提取液经减压过滤，浓缩，弗罗里硅土柱净化，定容后用GC-ECD检测。

Acetochlor existed in rice plant , rice was extracted by dichloromethane , with pressure reduction and pressure filtration , the extracts were concentrated , purified and detected by rotary densifier , Florisil column and GC-ECD respectively .

产物温合物减压过滤，以除去镁盐。

The mixture of products was filtrated by a vacuum pump to remove the magnesium salt .

基于对堤防管涌（流土）险情的发生、发展和破坏机理的分析，设计了一种新型的滤层结构，即包括减压、过滤和保护三层合一的滤垫。

Based on the analyses of the occurring , developing and failure mechanism of piping in a dike , a new filter structure , namely a filter mattress with a pressure reducing layer , a filter layer and a protective layer , is designed .