单词:noise levels
单词:noise levels 相关文章
This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute. Beauty is only skin deep. And the beauty of shiny white teeth is even less deep. Because a new study shows that fluoride forms a thinner protective shiel
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
[00:04.28]Reading COME AND EAT HEAR(1) [00:09.12]Wang Pengwei sat in his empty restaurant feelling very frustrated. [00:15.05]It had been a very strange morning. [00:17.92]Usually he got up early prepared his menu of mutton kebabs, [00:23.28]roast po
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
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
China's Tibet Autonomous Region is about to achieve a universal coverage of fibre-optical broadband service ahead of its schedule. As China further rolled out its universal broadband project, Tibet's broadband service is looking to reach 98% of admin