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In December 2013,a lasting haze pollution event occurred in the Central and East regions of China.Here in this paper,using a single-particle soot photometer (SP2),we studied mass concentrations,mixing states,and size distributions of black carbon (BC) in this event.The results showed that BC mass concentration in Nanjing during the observation period was in the range of 1.01-14.05 μg·m

Secondary organic aerosol (SOA) derived from isoprene epoxydiols (IEPOX) has potential impacts on regional air quality and climate yet is poorly characterized under NOx-rich ambient environments. We report the first real-time characterization of IEPOX-derived SOA (IEPOX-SOA) in Eastern China in summer 2013 using comprehensive ambient measurements, along with model analysis. The ratio of IEPOX-SOA to isoprene high-NOx SOA precursors, e.g., methyl vinyl ketone and methacrolein, and the reactive uptake potential of IEPOX was lower than those generally observed in regions with prevailing biogenic emissions, low NOx levels, and high particle acidity, elucidating the suppression of IEPOX-SOA formation under NOx-rich environments. IEPOX-SOA showed high potential source regions to the south with large biogenic emissions, illustrating that the interactions between biogenic and anthropogenic emissions might have played an important role in affecting the formation of IEPOX-SOA in polluted environments in Eastern China.

Volatile organic compounds (VOCs) is an important precursor of photochemical ozone pollution (O3) in the atmosphere. Their concentration variation directly affects the characteristics of the ozone pollution. The concentration, speciation of VOCs, ozone and its precursors in Nanjing were analyzed and measured using online gas detection systems in August 2013. VOCs/NOx discriminant method was used to get the sensitive control factors of ozone. The results showed that the averaged volume fraction of VOCs was 52. 05 x 10(-9), and the largest one reached 200 x 10(-9) in Nanjing urban district. The order of volume fraction of each species VOCs was alkaneoxygen-containing VOCsalkenearomatics. The averaged concentration of ozone was 76.5 microg x m(-1) and the exceeding concentration of hourly standard was 5.9%. The change trends of ozone precursors VOCs and NOx were basically identical and Ozone showed the obvious negative correlation during the period of high concentrations of ozone. There were some differences in the concentrations of the same VOCs in different ozone concentration periods. The ozone generation in Nanjing urban district was sensitive to VOCs, and Nanjing belonged to VOCs control area in summer.

Three catalysts CuO/Al2O3, CeO2/Al2O3 and CuO-CeO2/Al2O3 were prepared by the impregnation method. The textural and structural properties of the synthesized catalysts were characterized by N2 adsorption/desorption, SEM and XRD, and the effect of active ingredients, flow rate and reaction temperature on catalytic degradation of naphthalene (NaP) were investigated in fixed-bed reactor. The experimental results show that the prepared 18% CeO2/Al2O3 has a low catalytic activity of NaP. Nevertheless, both 18% CuO/Al2O3 and 9% CuO-9% CeO2/Al2O3 exhibit high catalytic activity whose removal efficiencies at 300°C can reach 91% and 89%, respectively. Besides, compared with CuO/Al2O3, CuO-CeO2/Al2O3 possesses a higher low-temperature activity. Furthermore, the variation of flow rates has little effect on the performance of two catalysts.

The influence of inorganic additives (NaCl, Na2CO3 and CaCO3) on the distribution of polycyclic aromatic hydrocarbons (PAHs) in the smoke and ash from mosquito coils burning was studied, GC-MS technique was applied to analyze the contents of 16 priority-controlled PAHs recommended by US EPA. The results show that 16 priority-controlled PAHs are detected in the smoke of mosquito coil without additives, characterized by the predominance of 2- to 3-ring PAHs, which are ranked as NaP (3.109 microg x g(-1))Phe (1.230 microg x g(-1))AcP (0.495 microg x g(-1))FluA (0.311 microg x g(-1)); the emission factors in the ash are also predominated by 2- to 3-ring PAHs, but the total PAHs emission factors in the ash are only 4.7% of those in the smoke. NaCl and Na2CO3 additives can not decrease the emission of PAHs but promote total emission factors and TEQ of PAHs in the smoke of mosquito coils increase remarkably. The best additive in this study is CaCO3. With the increase of the addition of CaCO3, the proportion for 2- to 3-ring PAHs in the smoke increases remarkably than that in the ash, while the status reverse for 5- to 6-ring PAHs. CaCO3 with mole fraction of 2.0% has the most excellent property to decrease total emission factors and TEQ of PAHs in the smoke of mosquito coils, and the total emission factors and TEQ of PAHs decrease 1.8% and 86.6% respectively compared with the control.

The hazardous organic pollutants generated from coal gasification, such as polycyclic aromatic hydrocarbons(PAHs), are highly mutagenic and carcinogenic. More researchers have paid particular attention to them. Using air and steam as gasification medium, the experiments of three kinds of coals were carried out in a bench-scale atmospheric fluidized bed gasifier. The contents of the 16 PAHs specified by US EPA in raw coal, slag, bag house coke, cyclone coke and gas were measured by HPLC to study the contents of PAHs in raw coal and the effects of the inherent characters of coals on the formation and release of PAHs in coal gasification. The experimental results showed that the distributions of PAHs in the gasified products are similar to raw coals and the total-PAHs content in coal gasification is higher than in raw coal(except Coal C). The total-PAHs contents increase and then decrease with the rise of fixed carbon and sulfur of coal while there has an opposite variation when volatile matters content increase. The quantities of PAHs reduce with the increase of ash content or the drop of heating value during coal gasification.