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Scientists know that the combination of extreme heat and pressure changes carbon into diamonds. Such heat and pressure exist only in the hot, liquid mass of molten rock deep inside the earth. It is th
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Rare Minerals May Be in North Korea 稀有矿物质可能在朝鲜发现 Hello and welcome back. Im Jim Tedder in Washington. Today we are going to talk about something that is worth a lot of money, and it is buried in the ground. Were not exactly go
2014年VOA慢速英语(二)月
This is Scientific American's 60-Second Science. I'm Steve Mirsky . Got a minute ? Were on the verge of finding out how frequently habitable planets occur in the universe. That was astronomer Alan Boss at the AAAS meeting on February 14th. And I thin
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This is the VOA Special English Economics Report. Today we continue our report on the group of chemical elements known as rare earth metals. These are mined from the earth and used to make technology from mobile phones to missiles. The United States
2010年VOA慢速英语(十)月
China has scrapped a quota system that was intended to restrict rare earth exports. The move involves 17 metals used in high tech sectors, it's aimed at complying with a World Trade Organization ruling released last year. The Ministry of Commerce iss
cctv9英语新闻2015年
Vital for so many modern technologies, rare earths remain among the most sought-after minerals on the planet. It was recently suggested at the American Association for the Advancement of Science that the sea beds should be mined for them. 对如此多现
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