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Die-hard advocates of alternate energy might fantasize about cars that could one day run on water. But scientists in India have gone a step further. They’ve mathematically modeled an engine that should allow a motorcycle to run on air—compressed air, that is. Their design is described in the Journal of Renewable and Sustainable Energy.

The hunt is on for alternatives to fossil fuels. Internal combustion¹ engines convert the energy in gasoline’s molecular² bonds into motion. But what if there were another way to make engine parts move?

Scientists in India were thinking of a well-directed wind. And after crunching³ the numbers on pressure and flow, they’ve concluded that a tank of compressed air could generate enough power to run a motorcycle for up to 40 minutes. The air would spin a turbine, which would then get things rolling.

Of course they’d need to design a tank that could store enough air to fuel a long haul. Current cylinders⁴ would need changing or charging after about 20 miles. Which would still cover a lot of commutes⁵ and trips to the grocery store.

And you’d still need to get air in the tank in a green way. Maybe a solar-powered, geothermal, wind-driven compressor?

Thanks for the minute for Scientific American’s 60-Second Science. I’m Karen Hopkin

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1 combustion
n.燃烧；氧化；骚动
参考例句：
We might be tempted to think of combustion.我们也许会联想到氧化。 The smoke formed by their combustion is negligible.由它燃烧所生成的烟是可忽略的。

2 molecular
adj.分子的；克分子的
参考例句：
The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。 For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

3 crunching
v.嘎吱嘎吱地咬嚼( crunch的现在分词 )；嘎吱作响；（快速大量地）处理信息；数字捣弄
参考例句：
The horses were crunching their straw at their manger. 这些马在嘎吱嘎吱地吃槽里的草。来自《简明英汉词典》 The dog was crunching a bone. 狗正嘎吱嘎吱地嚼骨头。来自《简明英汉词典》

4 cylinders
n.圆筒( cylinder的名词复数 )；圆柱；汽缸；（尤指用作容器的）圆筒状物
参考例句：
They are working on all cylinders to get the job finished. 他们正在竭尽全力争取把这工作干完。来自《简明英汉词典》 That jeep has four cylinders. 那辆吉普车有4个汽缸。来自《简明英汉词典》

5 commutes
上下班路程( commute的名词复数 )
参考例句：
She commutes from Oxford to London every day. 她每天上下班往返于牛津与伦敦之间。 Barbara lives in Oxford and commutes. 芭芭拉住在牛津，通勤往来。