"When you have a situation like this occur, you are bound to have a situation down the line where there could be a shortage in food, which can also trigger other negative situations, such as malnutrition, for example, or insufficient food for cattle, which is also another important economic sector in West Africa,".

VOA: standard.2009.09.08

But, can you see that as you get really close together the negative electronic cloud surrounding the two ions start to sense one another.

然后当你真的让它们,离得很近时,这两个离子周围的负电子云能感应到对方。

麻省理工公开课 - 固态化学导论课程节选

And shielding is a little bit of a misnomer because it's not actually that's the electron's blocking the charge from another electron, it's more like you're canceling out a positive attractive force with a negative repulsive force.

屏蔽有一点点用词不当,因为它事实上不是,电子阻挡了来自另一个电子的电荷,它更像你在用一个负排斥力，抵消一个正吸引力,但是屏蔽是考虑这个问题,的很好的方式。

麻省理工公开课 - 化学原理课程节选