单词：barium benzenesulfonate
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Abby: hi, my name's Abby. What's your name? Colin: I'm colin. It's nice to meet you. What do you do? A: I'm a freelance English teacher. How about you? C: I'm in between jobs at the moment. A: what kind of job are you looking for? C: I'd like to find
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This is Scientific Americans 60-Second Science. Im Sophie Bushwick. Got a Minute? What's the best way to find out if an unknown mixture contains a specific substance, like an environmental contaminant? You could use an expensive, bulky gas chromatogr
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By Sean Maroney Islamabad 28 September 2009 The head coordinator for the U.N. Humanitarian Affairs office in Pakistan says his agency is ready to handle what is expected to be a large number of families fleeing the South Waziristan tribal region as
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BBC Learning English Weekender Body image survey results Amber:Hello, I'm Amber, and youre listening to bbclearningenglish.com. In Weekender today, we listen to a report about a BBC survey of 25,000 young British people, asking about their body imag
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Indoor air pollution is a common threat to human health, the new study looked at five common house plants and found that when it comes to removing harmful chemicals from the air, those five plants are better than others. 室内空气污染对人类健康
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本期内容： A humble houseplant with a dash of rabbit DNA could help lower our exposure to indoor air pollution, new research suggests. Scientists have revealed that by inserting a rabbit gene into devils ivy the plant is able to clean the surrou
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