单词：space charge density
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As the old song has it, breaking up is hard to do. 正如一首老歌唱的一样，分手太难。 Not only is there the emotional angst, but in many cases one partner has to pack up and move out. 这困难之处不仅在于情感上的忧虑，在许
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By Peter Fedynsky Moscow 03 October 2007 October 4th marks 50 years since the former Soviet Union hurled humanity's first object into Earth orbit. It was a small round device known as Sputnik -- Russian for satellite -- with four antennas and a trans
2007年VOA常速英语（十月）
I should say that everything is just right so far. In the long term, gravity may turn out to be a little too strong, and one day it may halt the expansion of the universe and bring it collapsing in upon itself, till it crushes itself down into anothe
万物简史
Science and technology 科学技术 Astrochemistry 天体化学 The great test tube in the sky 空中的大试管 Space is one big chemistry set 宇宙是一个很大的化学装置 MOST people think of the empty space between the stars as being, wel
经济学人科技系列
The first rockets were Chinese. In the 1230s the armies of the Song dynasty, 首批火箭出现在中国。十三世纪三十年代，宋朝军队 who were fighting Mongol invaders, started launching fire arrows propelled by gunpowder some 300 metres
经济学人科技系列
After failing in Beijing's license plate lottery system for some three years, Qin Xiaofei finally made his decision in January to buy a battery-driven car to chauffeur his wife who has recently become pregnant. But, he says, one of the biggest concer
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