YRD	Yangtze River Delta
CFCs	Chlorofluorocarbons
HCFCs	Hydrochlorofluorocarbons
HFCs	Hydrofluorocarbons
ODSs	Ozone Depleting Substances
PMF	Positive Matrix Factorization
VOCs	Volatile Organic Compounds
CBPF	Conditional Bivariate Probability Function
EPA	U.S. Environmental Protection Agency
GC	Gas Chromatography
FID	Flame Ionization Detection
PLOT	Porous Layer Open Tubular
MS	Mass Spectrometric