Fourteen major cities in northwest China's Xinjiang Uygur Autonomous Region had their air quality improved in 2018, thanks to intensified efforts in environmental control.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/xinjiangs-major-cities-see-improved-air-quality
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/xinhua
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/china
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-monoxide
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ozone
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/pm-25
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-quality-monitoring
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/transport
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/nitrogen-dioxide
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/asia