"Just a back-of-the-envelope calculation shows that in the Philippines, if we in a year can be reaching just five thousand farmers and their fields can be increasing the yield by half a ton per hectare, we could be looking at profitabilities for those farmers in the range of half a million dollars."

VOA: standard.2010.07.28

But the beauty in this calculation is it shows that this concept of electron sharing in an unequal manner is sound and it gets you into the right ballpark.

但在这个计算过程中,真正漂亮的是对电子,非平均共价的考虑很完全,从而指引我们向一个正确的方向思考。

麻省理工公开课 - 固态化学导论课程节选