TY - JOUR A1 - Zhang, Q. A1 - Zhang, J. A1 - Xue, H. T1 - The challenge of improving visibility in Beijing JO - Atmos. Chem. Phys. Discuss. J1 - ACPD VL - 2010 SP - 6199 EP - 6218 Y1 - 2010/03/05 PB - Copernicus Publications SN - 1680-7375 UR - https://acp.copernicus.org/preprints/10/6199/2010/ L1 - https://acp.copernicus.org/preprints/10/6199/2010/acpd-10-6199-2010.pdf DO - 10.5194/acpd-10-6199-2010 ER -