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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

One of the world's most amazing migration is about to begin in earnest: 300 million monarch butterflies spread across North America are about to converge on small forests in the mounts of Mexico. This year, the butterflies have an unusual company as

发表于:2019-01-08 / 阅读(119) / 评论(0) 分类 2005年NPR美国国家公共电台

By Robert Berger Jerusalem 14 November 2009 An ultra-orthodox Jewish man is seen next to Intel's Jerusalem office building, 14 Nov 2009 Alleged violations of the Jewish Sabbath by a top international company prompted religious protests in Jerusalem

发表于:2019-01-14 / 阅读(58) / 评论(0) 分类 VOA标准英语2009年(十一月)

China has long depended on coal-burning power plants to fuel its explosive growth over the past three decades. As a result, air pollution has risen to alarming levels in central and eastern regions. Policymakers have been working hard to shift the co

发表于:2019-01-19 / 阅读(102) / 评论(0) 分类 2017CRI中国国际广播电台

1. The shortest complete sentence in the English language consists of only one word and that is Go. 英语里由一个单词组成的最短的完整的句子就是GO. 2. The oldest word in the English language is town. 英语里最有年头的一个词

发表于:2019-02-25 / 阅读(103) / 评论(0) 分类 英文语法词汇