碳链末端的原子发射电子到周围的磷光屏，得到原子核周围电子云的图像。

The atom at the tip of the chain emitted electrons onto a surrounding phosphor screen, rendering an image of the electron cloud around the nucleus.

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This blue chain here goes from 5' carbon all along the chain and there's a 3' carbon left open at the bottom.

这条蓝色的链,从5'碳开始一直向下延伸,以3'碳做为链的末端

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