"The bacteria concentration after filtration depends on the initial concentration of bacteria in water, " said developer Dr Cui of Stanford University.

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Of the north-east's GDP, two-thirds was being produced by state-owned firms, many of which were loss-making, says Cui Wantian of Liaoning University (he thinks they now contribute less than 50%, compared with about 30% nationally).

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Also at the meeting were China's new finance minister Lou Jiwei, U.S. Ambassador Gary Locke, an assistant Chinese foreign minister Cui Tiankai, and other officials of both governments.

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Although a commercial version is some way off, Dr Cui believes there could be a mass-market version of his technology available.

CNN: Nanotech and 'tea bag' to clean up drinking water

"It would be appropriate for someone to step forward and give us an explanation, otherwise international confidence in the recovery and growth of the global economy might be hurt, " Mr. Cui said.

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"The GASC has decided to appoint Wei Di as the new director of China's Soccer Administrative Center, " its vice-minister Cui Dalin told reporters, according to Xinhua.

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"The value of China's currency is determined by the market fundamentals, not by any politicians, " Cui replied.

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