[Comparison of Characteristics and Reactive Oxidative Species of PM2.5 in Xi'an, China During Haze and Clean Days].

摘要: PM2.5 samples were collected in Xi'an, China during haze(2015-11-30-2015-12-9) and clean days(2016-01-13-2016-01-22). mass, organic carbon(OC), elemental carbon(EC), water-soluble ions(i.e., NH4+, NO3-, SO42-) measured to investigate the characteristics of two typical pollution processes. The result showed that masses were(170±47.5) μg·m-3 and(48.6±17.9) for haze days, respectively, with accompanied by low visibility, high humidity, calm wind, other adverse weather conditions. secondary inorganic aerosol(SIA) including SO42- accounted 49.8%±13.1% 19.4%±5.95% mass respectively. sulfur nitrogen oxidation ratios(SOR NOR) on days 0.282±0.157 0.269±0.124, which much higher than those days(0.189±0.057 0.077±0.046). average concentration carbon(SOC) days(6.22±3.87) was 5 times days(1.44±1.63) μg·m-3. Secondary conditions main reasons heavy haze. Finally, level particulate-Reactive Oxygen Species(ROS)was 2',7'-dichlorofluorescin diacetate(2',7'-DCFH) fluorescence method, ROS (as H2O2) was(4.99±1.54) nmol·m-3 and(0.492±0.356) days. Accumulation effect process may be increase under Xi'an. Positive correlations(P<0.05) between concentrations ions NO3- indicated participate SIA.