That compresses the plutonium while it is simultaneously bombarded with neutrons from a trigger made of polonium, and thus begins the second stage.

这个过程能压缩钚，并与此同时钚也会受到由钋组成的触发器散发出的中子的轰击，这样就引发了第二个阶段。

youdao

The second leg of the call begins as soon as the destination party or answering device answers the telephone.

呼叫的第二档从目标方或应答设备接听该电话时就立即开始。

youdao

Now the second phase of SOA governance begins.

也昭示着第二个SOA治理时期的开始。

youdao

It's for this second printing that Milton adds the headnote that you see here that now begins the poem: "In this Monody the Author bewails a learned Friend, unfortunately drown'd in his Passage from Chester on the Irish Seas, 1637."

在第二版中，他加上了眉批,你们现在都能看到：,“周一作者缅怀了一位，不幸于1637年在爱尔兰海上,溺水而亡的挚友“

耶鲁公开课 - 弥尔顿课程节选

The second episode begins in a sweat lodge, where Walt has joined Henry and other tribal members in a sacred ceremony.

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The first and most important trial of the second Clinton Administration begins this week, when the President sends his budget to Congress.

CNN: AllPolitics - TIME This Week

The second series of the programme begins on BBC2 on 23 June with The Bodies in the Well.

BBC: Crime writers back Dundee University ?1m morgue fund