氟化汞(II) {二氟化汞}

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(223) / 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

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科技之光

VOA慢速英语2012 Project Mercury: The American Space Program Begins

Project Mercury: The American Space Program Begins SHIRLEY GRIFFITH: EXPLORATIONS -- a program in Special English by the Voice of America. (SOUND) That announcement was made May fifth, nineteen sixty-one. It was the first manned flight of project Mer

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2012年VOA慢速英语(七)月

2005年NPR美国国家公共电台三月-Studies Find High Mercury Levels in the W

Studies that will be released today show that fish, birds and mammals in New England have significant amounts of mercury in their bodies. The studies find the toxic metal in some unexpected habitats and they suggest that power plants in the Midwest a

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2009年NPR美国国家公共电台7月

彭蒙惠英语：The Mercury Mess

The Mercury Mess By Samantha Levine / 2004, as first appeared in U.S. News nbsp; What are the dangers of mercury in fish? Can the mercury mess be cleaned up? 1 Are these fish safe to eat?” It’s a

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彭蒙惠英语

口腔临床英语对话第29期:正畸治疗(2)

Is it necessary to have cavities in the baby teeth repaired? 乳牙蛀成了洞还有必要补上吗？ If the baby teeth are going to fall out, I don't think that it matters if they become decayed. 如果乳牙是要脱落的，我想蛀了也没有关

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口腔临床英语对话

VOA慢速英语2009-EXPLORATIONS - Project Mercury: The US Space

VOICE ONE: EXPLORATIONS -- a program in Special English by the Voice of America. (SOUND) That announcement was made May fifth, nineteen sixty-one. It was the first manned flight of project Mercury. Today, Tony Riggs and Larry West tell about the beg

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VOA慢速英语2009年（六）月

VOA慢速英语2013 How the 'Mercury 13' Led the Way for Women in the US Space Program

How the 'Mercury 13' Led the Way for Women in the US Space Program Im Steve Ember. And Im Barbara Klein with EXPLORATIONS in VOA Special English. Today we tell about a program in the nineteen sixties to train women as astronauts. Today they are known

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2013年VOA慢速英语(五)月

VOA慢速英语2013 EXPLORATIONS - How the 'Mercury 13' Led the Way for Women in the US Space Program

EXPLORATIONS - How the 'Mercury 13' Led the Way for Women in the US Space Program Im Steve Ember. And Im Barbara Klein with EXPLORATIONS in VOA Special English. Today we tell about a program in the nineteen sixties to train women as astronauts. Today

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2013年VOA慢速英语(四)月

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

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VOA标准英语2010年(十)月

科学美国人60秒 SSS 海狸牙齿的奥秘

Ah yes.The ol' fluoride rinse at the dentist. Not pleasant. But hey, good for your teeth, right? 没错，这是牙医洗牙用的含氟漱口水。确实够闹心的。但毕竟对你的牙齿有益不是吗? Well now materials scientists have been

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2018年科学美国人1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

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科技之光

SCIENCE IN THE NEWS - Mercury in Fish / Life on Land / The G

SCIENCE IN THE NEWS - Mercury in Fish / Life on Land / The Goldman Environmental Prize By Broadcast: Tuesday, May 11, 2004 (THEME) VOICE ONE: This is SCIENCE IN THE NEWS, in VOA Special English. I'm B

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科技之光

MESSENGER Probe Sends First Mercury Images

The U.S. space agency(代理中介) has released the first ever image taken of the surface of Mercury from a spacecraft orbiting the planet. The black and white image, posted on the NASA website Tuesday, shows a surface pocked with craters of varying

发表于:2019-01-31 / 阅读(177) / 评论(0)

英语新闻

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(171) / 评论(0)

英语单词荟萃

NASA Messenger Probe Set for Historic Orbit Around Mercury

The U.S. space agency NASAs Messenger probe（正直的，廉洁的） is scheduled to reach Mercury later this week, and become the first spacecraft to orbit the planet closest to the sun. During Messengers year-long orbital mission, scientists exp

发表于:2019-02-05 / 阅读(169) / 评论(0)

英语新闻

MESSENGER Spacecraft Will Be First to Orbit Planet Mercury

The U.S. space probe MESSENGER is poised to enter orbit around Mercury（水银） early Friday, Universal time, capping a nearly seven-year journey to the solar systems innermost planet. Scientists with the U.S. space agency, NASA, hope the orbiting

发表于:2019-02-05 / 阅读(153) / 评论(0)

英语新闻

英语听力：自然百科金星和水星旅行指南 Venus and Mercury-2

Ever wanted to be an astronaut? Imagine it was you, who was heading to the hot zone of the two inner planets, where would you go? What would you see? And how would you survive? The latest robotic machines have revealed more about these worlds than ev

发表于:2019-02-05 / 阅读(211) / 评论(0)

自然百科2012年

VOA常速英语2008年-Mercury Seen in New Light

By Paul Sisco Washington, DC 15 February 2008 Scientists have started analyzing data and images acquired when the Messenger space probe passed within 200 kilometers of the planet Mercury last month. It was the first flyby of the solar system's inner-

发表于:2019-02-06 / 阅读(227) / 评论(0)

VOA常速英语2008年（二月）

英语听力：自然百科金星和水星旅行指南 Venus and Mercury-7

Like Mercury, the earth takes a beating from the sun's violent temper. Flares, sun storms and other solar hissy fits can cause electronic mayhem for the satellites that roam above our heads. Fortunately, the earth is protected from this radiation by

发表于:2019-02-15 / 阅读(297) / 评论(0)

自然百科2012年

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