ducted

a ventilation system that must be ducted through the wall.

必须穿过墙壁管道通风系统。

A test of arrosion performance of anticorrocive built-up weld layer in different meeiums was con-ducted by using a self-made arrosion testing machine.

用自制腐蚀磨损试验机对耐蚀堆焊层在不同介腐蚀磨损性能进行了试验，结果表明：腐蚀介不同，堆焊层磨损速率也不同。

In addition, the USAF continues to fund development work of the Aerojet (formerly Atlantic Research) Variable Flow Ducted Rocket ramjet system as a future propulsion option for an extended range AAM.

此外，美国军继续投资于航喷气研究所（原来大西洋研究所）可变喷流管火箭发动机系统，将其作为增程弹未来推进选项。