加氟化物的酸热分解

SSS 2010-12-29

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

发表于:2018-12-02 / 阅读(89) / 评论(0)

Scientific American(十二)月

Dental Health

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

发表于:2018-12-07 / 阅读(57) / 评论(0)

科技之光

CRI实用英语课堂 Unit 25 Environmental Protection II 环境保护（中）

Part 4 Air Pollution 空气污染 Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99.9% nitrogen, oxygen, water vapor and inert gases. Human activities ca n release substances into the air, some

发表于:2019-01-02 / 阅读(109) / 评论(0)

CRI实用英语课堂

VOA标准英语2010年-Coal Burning Linked to Fluoride Diseas

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

发表于:2019-01-14 / 阅读(69) / 评论(0)

VOA标准英语2010年(十)月

SCIENCE IN THE NEWS - Dental Health

SCIENCE IN THE NEWS - November 26, 2002: Dental Health By Nancy Steinbach VOICE ONE: This is Steve Ember. VOICE TWO: And this is Bob Doughty with Science in the News, a VOA Special English program abo

发表于:2019-01-30 / 阅读(67) / 评论(0)

科技之光

学个词 Learn a Word-VOA英语教学 2280-fluoride

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

发表于:2019-02-02 / 阅读(60) / 评论(0)

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