Bacterial cells are small, one to two microns in diameter and this shows a picture of a common bacterium called E. Coli.

细菌细胞很小,直径只有一到两个微米,这张图片是一种常见细菌,大肠杆菌

耶鲁公开课 - 生物医学工程探索课程节选

If we think of the size of a typical atom, we would say that would be about 10 to the negative 10 meters. So, we can see the diameter of a nucleus is absolutely smaller really concentrating that mass into a very small space.

一个普通细胞的大小，抱歉，我和细胞核搞混了0,如果我们考虑，一个普通原子的大小,这大概是10的负十次方米,所以原子核的直径确实非常小,真的是把质量。

麻省理工公开课 - 化学原理课程节选

It looks a little something like that, and the screen doesn't quite do it justice here, Z but there's two alphabets; A through Z, and then A through Z, -- but the inner A through Z is on a small -- it has a smaller diameter; so it's a ring of letters.

它看起就像那样的东西，那个画面做的不是这么公正，这里有两个字母表，A到Z，然后A到，但是戒指内部的A到Z是在一个小直径的上面-,它有一个小的直径，所以它是一个有字母的戒指。

哈佛公开课 - 计算机科学课程节选