All bodies emit heat rays no matter how low or high their temperatures are.

不论物体的温度有多低或多高，它们都发射出热射线。

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When the sun's rays hit the earth, a lot of the heat is reflected back into space.

太阳光线照射到地球时，大量的热被反射回太空。

《牛津词典》

Heat, too, makes our environments tolerable and some ultraviolet rays penetrate the atmosphere.

热也使我们的环境变得适宜生存，而且一些紫外线会穿透大气层。

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But the earth itself radiating energy outwards in the form of long-wave heat rays.

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What is certain is that the limitless imagination of mankind has turned science fiction heat rays into the near future reality of weapons on the battleground.

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Using heat-rays on the enemy might look bad in the newspapers, and put civilians off their breakfast.

ECONOMIST: Electromagnetic weapons