And that's all that's big enough to pass through or small enough to pass through. And if we go up even just one row on the periodic table to potassium, what we actually see is now that it's going to be too large, and, in fact, a potassium solvated with one water molecule won't go through our channel.

就是这样刚好大到它通过,或者说刚好小到它通过,即使我们再沿着周期表往下走仅仅一行到钾离子，我们看到的就将是它的个头太大了，实际上，溶解于一个水分子的单个钾离子,不能穿过我们的通道。

麻省理工公开课 - 化学原理课程节选

Because it's a gel electricity is going to move through the gel because there are ions in it the same way - for the same reason you don't drop an electrical device into the bathtub because charge moves through water that has ions in it.

由于凝胶中存在离子,电流会通过凝胶,同样--,因为同样的原因你不会把电器扔进浴缸里,因为水里也有离子,所以水可以导电

耶鲁公开课 - 生物医学工程探索课程节选