单词：erbium-doped yttrium lithium fluoride laser
单词：erbium-doped yttrium lithium fluoride laser 相关文章
07 牙病的预防与治疗 DATE=2-27-01 TITLE=SCIENCE IN THE NEWS #2113 - (1)Dental Health BYLINE=Nancy Steinbach VOICE ONE: This is Sarah Long. VOICE TWO: And this is Bob Doughty with Science in the
科技之光
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）
Parts of Chile are facing a growing water crisis. The Reuters news agency reports the government is taking steps to protect the countrys water supplies from mining operations. But for many years, the Chilean government approved water extraction right
2018年VOA慢速英语(九)月
A cluster of villages in China's Guizhou province has been plagued by an outbreak of disease that damages teeth and bones. Now, a new study by Chinese and American researchers puts the blame on polluted coal burned in home fireplaces. In small quanti
VOA标准英语2010年(十)月
今天我们要学的词是 fluoride. Fluoride 氟化物。The U.S. government is lowering the recommended amount of fluoride added to drinking water for the first time in more than 50 years. 美国政府50多年来首次降低饮用水建议添加的氟
英语单词荟萃
Ytterby 瑞典小镇伊特比 yttrium 钇 (1794) erbium 铒 (1842) terbium 铽 (1842) ytterium 镱 (1907) 1794年在瑞典小镇伊特比的黑石中发现了化学元素钇，决定用 Ytterby命名该元素：yttrium。1842 年在该镇的黑石中发
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