Environment Research Institute University 266237;
Department of Environmental Systems Science Federal Institute of Technology Zurich 8092;
Department of Water Resources and Drinking Water Federal Institute of Aquatic Science and Technology 8600;
Qingdao Eco-Environment Monitoring Center of Shandong Province 266003;
College of Oceanic and Atmospheric Sciences University of China 266100;
School of Environmental and Geographical Sciences Normal University 200234;
Nitro-aromatic compounds; Fine particles; Source apportionment; Originating region; Combustion activities;