Scientists from the National Institute of Diabetes and Digestive and Kidney Diseases measured the energy content of America's wasted food.

VOA: special.2010.11.23

So, if you could make automobiles with a high magnesium content, you would reduce the mass, reduce the energy required, and thereby reduce the environmental impact.

所以，如果你能用含镁量,很高的材料来制造手机，你就能减轻手机的质量，减少制造所需能量，因此减轻了对环境的破坏。

麻省理工公开课 - 固态化学导论课程节选