More powerful particle accelerators atom smashers, they used to call them have allowed physicists to learn ever more about the sub-atomic particles that are the basic building blocks of all matter.

VOA: standard.2010.03.05

And what we've been talking about with all of these properties are, of course, how can we figure out what that is for a certain atom by looking at the periodic table, so we want to think about the periodic trend for atomic radius.

对于我们讲过的这些性质，我们所讨论的一直都是,当然是，我们如何能够判断某一个原子的这些性质,通过观察周期表，因此我们需要思考一下原子半径的周期性规律。

麻省理工公开课 - 化学原理课程节选

The number of electrons in an atom is deduced to be approximately equal to half the atomic weight.

原子中的电子数,将近是原子质量的一般。

麻省理工公开课 - 固态化学导论课程节选

And many of these samples we study literally at the atomic, single-atom level.

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