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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
VOA常速英语2008年（四月）
New Laser Heals Wounds Faster, Without Scarring 新激光治疗伤口好的更快且没有疤痕 All surgical patients want their wounds to heal quickly with the least possible scarring. But traditional stitches, clips and more modern chemical glues
VOA标准英语2015年(四月)
Sometimes it is hard to see the light, especially it lies in the invisible spectrum, like ultrared, ultraviolet radiation. But if you long to see the unseeable, you might interested to hear that under certain conditions people can catch a glimpse of
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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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This is Scientific American 60 Second Science, I am Karen Hopkin, this will just take a minute. Every year, about 10 million tons of paper winds up in American landfills and incinerators, which is not only wasteful but adds CO2 to the atmosphere. Rec
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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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