Researchers usethese X-ray flashes to resolve structures as small as one ten billionth of ameter (0.1 nanometer) in size. That is roughly the diameter of a hydrogen atom.

【译】研究人员用X射线光来分辨尺寸为百亿分之一米（即0.1纳米）的微小结构，这种尺寸结构接近氢原子直径。

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And, that's a good thing to know because if you come out with an answer that's somewhere near the diameter of the universe and it's supposed to be the diameter of an atom, then you will know that you probably made a mistake.

这是我们需要知道的,因为当你做一道题得到的答案,是宇宙的直径,而正确答案是原子直径时，你能很快发现你的错误。

麻省理工公开课 - 固态化学导论课程节选

In addition, if we compare this to the diameter of an atom, which is on the order of somewhere between one and ten angstroms, now we're seeing that, in fact, this wavelength is significantly larger than its environment.

另外，如果我们把它,与原子的直径相比，原子直径近似1到10埃米之间,我们现在来看看，事实上，这个波长比它所处的环境大很多。

麻省理工公开课 - 化学原理课程节选

Even if experimenters bounce the beams to and fro to increase the effective length of an interferometer's arms to more than 100 kilometres, the expected difference in length between the two beams' paths still amounts to less than a hundred-millionth of the diameter of a hydrogen atom.

ECONOMIST: Fundamental physics

Laser interferometers are looking for disturbances in their experimental set-ups that are equivalent to mere fractions of the diameter of a proton, one of the particles that make up the nucleus of an atom.

BBC: Lab tuned to gravity's 'ripples'