矿质磷矿石

By David Lewis A natural resources watchdog group issued a report Tuesday warning that smuggling and corruption are costing the Democratic Republic of Congo millions of dollars a month in lost revenue

发表于:2018-12-08 / 阅读(63) / 评论(0) 分类 VOA2004(下)--世界经济

pH - a measure of how acid or alkali a solution is. As the pH gets lower, the solution is more acid. At a pH of 7 the solution is neither acid nor alkali. pH is the inverse of the logarithm of the con

发表于:2019-01-03 / 阅读(59) / 评论(0) 分类 医务英语

This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. Batteries of the future need to deliver more energy, and they need to be smaller. Researchers at MIT think they have developed a technology that can, a

发表于:2019-01-08 / 阅读(78) / 评论(0) 分类 Scientific American(四)月

Harnessing the Mineral Wealth of Poor Countries 新方针指导贫穷国家正确利用其丰富矿藏 Developing countries with potential mineral riches have often fallen prey to corruption and mismanagement. As a result, theyve failed to benefit fr

发表于:2019-01-14 / 阅读(50) / 评论(0) 分类 VOA标准英语2012年(二月)

Cameroon's new mineral research center will begin operations this year. South Korean mining researchers are making trips to Cameroon to determine the overall cost of the facility, to be located in the capital, Yaounde. They say the center will cost s

发表于:2019-01-14 / 阅读(89) / 评论(0) 分类 VOA标准英语2011年(二月)

gullet 水道 stream, brook 小溪 rapids 急流 whirlpool 旋涡 underground river 暗河 subterranean river 地下河 drainage net 河网 upstream , headwaters上游 midstream 中游 deflation 干涸 mother river 主流 tributary 支流 deposit 淤积

发表于:2019-03-13 / 阅读(118) / 评论(0) 分类 托福英语