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In business, Optus has called for Telstra's proposals on its participation in the national broadband network to be blocked. Optus' chief executive Paul O'Sullivan says Telstra's current plan for the separation of its retail and wholesale arms wholesa

发表于:2018-12-11 / 阅读(78) / 评论(0) 分类 澳洲ABC新闻快递2011年

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

AGRICULTURE REPORT – March 12, 2002: Carbon Dioxide and Crops By George Grow This is the VOA Special English AGRICULTURE REPORT. Increasing levels of carbon dioxide gas in Earth’s atmosphere have

发表于:2019-01-30 / 阅读(71) / 评论(0) 分类 农业与发展