单词：N-Triethylaminoethanol
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This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute. As Valentines day approaches, remember, its the thought that counts. Just ask a decorated cricket. Because according to a study published in the January
Scientific American(一)月
By Greg Flakus Houston 16 October 2007 In recent months food costs in the United States have gone up by well over six percent and some economists see government-mandated use of bio-fuels as a key reason. But, as VOA's Greg Flakus reports from Houston
2007年VOA常速英语（十月）
By Jeffrey Young Washington 16 October 2007 U.S. farmers have gone through many cycles of boom and bust. But as VOA's Jeffrey Young reports, prospects for American agriculture are looking up, thanks to rising crop prices and land values, especially i
2007年VOA常速英语（十月）
By counting back through these layers and measuring the amount of lead in each, he could work out global lead concentrations at any time for hundreds, or even thousands, of years. The notion became the foundation of ice core studies, on which much mo
万物简史
Lead is a neurotoxin. Get too much of it and you can irreparably damage the brain and central nervous system. Among the many symptoms associated with overexposure are blindness, insomnia, kidney failure, hearing loss, cancer, palsies, and convulsions
万物简史
If you were going to a restaurant and wanted a healthier option, 如果你去饭店，你想吃得健康一点， which would you choose, grilled or fried chicken? 你会选择哪种食品呢，烤鸡还是炸鸡？ Now most people would answer grill
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