The agreement to be signed Thursday replaces the START-1 treaty, which U.S.President George H.W.Bush and Soviet President Mikhail Gorbachev signed in 1991.

VOA: standard.2010.04.04

And if you put this in the well-ventilated area, if you prepare this outside, the h c n gas will actually be released into the air, so you're safe, you can eat it later.

而如果你把它们放在通风良好的地方，在室外处理，那么氰化氢气体,将会被释放到空气中，这样你就安全了，过后就可以吃了。

麻省理工公开课 - 化学原理课程节选

So in terms of thinking about ethane, we actually have two bond types that we're going to be describing just in terms of the carbon-carbon bond and then the carbon h bonds.

对于乙烷，我们有两种键,我们继续讨论一下,碳碳键,和碳氢键。

麻省理工公开课 - 化学原理课程节选