It is an electron beam. In the 1890s, the latter part of the 19th century a very fashionable word was "ray."

那是个电子束，在十九世纪九十年代，就是19世纪末，一个很时髦的词汇-“光线。”

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Instead, a single wavelength can be selected to produce the X-ray equivalent of a pure-colour beam of light.

事实上单独某一个波长的射线就可以产生好象一束单色光一样的纯净的伦琴射线。

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The researchers then narrowed down the X-ray beam so that it was just a tenth of a millimetre across and found that the fractal-like regions occurred only where the beam struck the sample.

研究人员随后将X射线的光束收窄，使其只有十分之一毫米宽，这时他们发现，碎片形的区域只出现在射线照射的地方。

youdao

It is an electron beam. In the 1890s, the latter part of the 19th century a very fashionable word was "ray."

那是个电子束，在十九世纪九十年代，就是19世纪末,一个很时髦的词汇-“光线“

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