They used a method called diffusion tensor imaging.

VOA: special.2010.12.21

Molecules are produced here and they flow directly over, usually by diffusion, to the neighboring molecule.

这里产生的分子,通常是以扩散的方式,直接到达临近的分子

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Diffusion mixes things very well, but as the size gets bigger, diffusion becomes very slow.

扩散作用使物质充分混合,但随着细胞变大后,扩散作用就捉襟见肘了

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There was no equivalent of the Royal Society that you're reading about in London that was very important in the diffusion of the scientific revolution.

在俄国没有与英国皇家学会一样的组织,伦敦的皇家学会对科学革命的传播非常重要

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On the other hand, if somebody says, "Somebody call the police," well, I got things to do and so diffusion of responsibility explains both when we're willing to do terrible things and also when we're willing to help people who are in trouble.

但是如果有人叫，“来人，快报警”,“我有事要忙”,责任分散,既能解释我们在什么情况下会干坏事,也能解释我们在什么情况下会帮别人。

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These details aren't important, it is described in your book, but the thing that is important to know is that diffusion occurs fast over short distances, but because of the physics of diffusion it occurs slowly over longer distances.

这些具体细节无关轻重,书上都有,重点是你要明白,距离越短扩散越快,由于扩散现象的物理特性,距离越长扩散越慢

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