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Global warming may or not be the great environmental crisis of the 21st century, butregardless of weather it is or isn't we won't do much about it. We will argue over it and may even, as a nation, make some fairly solemn-sounding commitments to avoid
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This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. There's a huge, gunky brown cloud that lingers over south Asia and the Indian Ocean each winter. Its been known to cause respiratory diseases and even
Scientific American(一)月
(man) Today I want to discuss fossil fuels such as coat, oil, and natural gas. The term fossil fuel refers to the trapped remains of plants and animals in sedimentary rock. You see, living plants trap energy from the sun by the process of photosynth
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Researchers get same yields with fewer fertilizers, pesticides Steve Baragona | Washington, DC 18 May 2010 Fossil energy use was compared among different crop rotation systems in a field experiment conducted between 2003 and 2008 in Boone Co., Iowa R
VOA标准英语2010年(五)月
Oil is good and bad. Its good because it helps our energy needs. Its bad because it causes pollution. Oil is a fossil fuel. Burning it produces carbon dioxide (CO2). This is one of the biggest causes of global warming. There isnt much oil left in the
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By Paul Sisco Washington 07 March 2007 watch Ethanol Alternative Fuel President Bush speaks to reporters about how cellulosic ethanol can be produced from biomass such as spruce wood chips President Bush leaves this week for a five nation Latin Amer
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