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来源: 于 2013-04-04 05:27:15 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

Obviously 24/7 monitoring and charting, or even simpler methods is more effective for pollution control.  

 However, that will increase the costs. 

Sometimes, a plant may simply passe tests by bribing EPA, due to the wide spread corrections in China, as you can imagine.