造船工业。救火水管。双铰链卷盘。

Shipbuilding. fire hose. double hinge reels.

youdao

Lewin教授利用橡胶水管、有孔的木盒、金属盘以及其它自制的装置来示范物体如何发声。

Walter Lewin USES rubber hose, wooden boxes with holes, metal plates and an assortment of other home-made instruments to demonstrate how objects produce sound.

youdao

分层注水管柱有效率低一直是困扰临盘油田开发生产的一大难题。

Low separate flooding string efficiency is one of the main problems in the exploitation of the Lin-pan Oilfield.

youdao