单词：double heterojunction laser
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By Carol Pearson Washington 30 April 2008 Ten years ago, the U.S. Food and Drug Administration approved LASIK, eye surgery with a laser that enables people to see without glasses. But about five percent of LASIK procedures fail, and those patients ca
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The United States Navy has demonstrated a new laser weapon operating in the Persian Gulf. The Laser Weapons System, or LaWS, is deployed on the USS Ponce transport ship. A live test firing of the weapon was recently carried out for Cable News Network
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By Paul Sisco Washington 14 November 2007 At the McDonald Observatory in western Texas, a unique space program has been quietly underway for more than 30 years. It is called the Lunar Laser Ranging Program. VOA's Paul Sisco has more. Research scienti
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Unit 17 第十七单元 Conversation 1 会话 1 A:Miss Sun,could you please type this report for me? A:孙小姐，请替我打这份报告好吗？ B:Certainly,Mr. Baker. B:当然，贝克先生。 A:Could you please double space it so I can make co
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