一兆焦相当于一个一吨重的物体以160公里/小时的速度撞一面墙产生的能量。
A megajoule is equivalent to the energy released when a one-tonne vehicle slams into a wall at 160kmh.
上述区域内每4平方公里范围的稀土元素储量，即可满足日本每年约30000吨的需求。
Rare earth elements from 4 square kilometers of such areas could meet Japan's annual demand of about 30, 000 tons.
这些由Wajih Naqvi和维克多•斯莫塔希克领导的研究者给300平方公里的海域里面投加了6吨的可溶于水的硫酸铁作为浮游生物的肥料已让他们生长。
Those researchers, led by Wajih Naqvi and Victor Smetacek, created a bloom of phytoplankton by fertilising an area of 300 square kilometres with six tonnes of iron sulphate, which dissolves in water.
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