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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
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By Brian Padden Irbil, Iraq 27 September 2007 Recent outbreaks of cholera in parts of Iraq highlight the need for basic services like clean water.Development projects in much of the country have been delayed because of the deteriorating security situ
2007年VOA标准英语（九月）
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
Scientific American(四)月
This is the VOA Special English Development Report. More than one billion people around the world do not have clean drinking water. Their water supplies are unsafe because of natural or man-made pollution, such as industrial chemicals or human and a
VOA慢速英语2007年（九）月
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Ecolab Inc., an American global provider of clean energy technologies and services, has made great progress on helping industries in China to produce their goods with less water consumption. Those industries include dairy plants, food industries, ste
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