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Blue skies pictured at Beijing Economic-Technological Development Area (BDA), Aug 31. BDA recently announced that the average concentration of PM2.5 in the area during July was 46 ug/m3, representing a year-on-year decrease of 20.7 percent, thanks to BDA’s efforts to control dust pollution and the emission of volatile organic compounds. [Photo/kfqgw.beijing.gov.cn]