n.瓣膜；真空管；阀门；电子管
The valve of the heart allows the blood to pass in one direction only. 心脏的瓣膜使血液只能朝一个方向流动
We need a valve detector. 我们需要个真空管检波器。
The pump sucks air out (of the vessel) through this valve. 这台泵通过这个阀门把(容器中的)空气抽出。
We need an eye bolt to fit this valve. 我们需要一个有眼螺栓来固定这个阀门。
Have you turned off the water valve? 你关掉水阀了吗？
John Ambrose Fleming invents the two-element "Fleming Valve". 约翰.
双壳类,蚌类
