单词：eka-cesium
【金+法】
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Youve given some thought to oxygen, carbon, uranium. But youve probably never mused about the element ytterbium, symbol Yb. A new study by scientists at the National Institute of Standards and Technology, or NIST, says that ytterbium could find a rol
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By Saqib ul-Islam Washington 12 October 2009 Amreeka's stars, pictured on the movie's promotional poster What is it like for a mother and her teenage son to settle in America? And what if they are Palestinian and their arrival coincides with the ons
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