In this paper,a method is established to quantitatively partition fractional contributions of polycyclic aromatic hydrocarbons(PAHs) in fine atmospheric particulate matters by using stable carbon isotopic analysis. Dichloromethane extraction,TLC purification,and gas chromatography-combustion system and isotope mass spectrometry(GC/C/IRMS),are used to measure the stable carbon isotope compositions(δ~(13)C).The fractional contributions of coal combustion,vehicle exhaust and biomass burning to the PAHs in the fine particulate matters (PM_(2.5)) collected in Jiading district,a suburb of Shanghai,are estimated.The results show that theδ~(13)C values increase with decreasing molecular weight.The coal combustion and biomass burning play bigger role than vehicle exhaust in the PAHs,compared to theδ~(13)C values of PAHs in all kinds of potential pollution sources.The estimated contributions from coal combustion,vehicle exhaust and biomass burning to PAHs of PM_(2.5) range from 3%- 21%, 29%- 33%and 46%- 67%,respectively,which agree well with the surrounding condition of the sampling site, indicating that it is feasible to estimate the fractional contributions of PAHs quantitatively by using stable carbon isotopic analysis.

To effectively reduce urban carbon emissions and verify the effectiveness of currently project for urban carbon emission reduction,quantitative estimation sources of urban atmospheric CO2 correctly is necessary.Since little fractionation of carbon isotope exists in the transportation from pollution sources to the receptor,the carbon isotope composition can be used for source apportionment.In the present study,a method was established to quantitatively estimate the source of urban atmospheric CO2 by the carbon isotope composition.Both diurnal and height variations of concentrations of CO2 derived from biomass,vehicle exhaust and coal burning were further determined for atmospheric CO2 in Jiading district of Shanghai.Biomass-derived CO2 accounts for the largest portion of atmospheric CO2.The concentrations of CO2 derived from the coal burning are larger in the night-time（00：00,04：00 and 20：00） than in the daytime（08：00,12：00 and 16：00）,and increase with the increase of height.Those derived from the vehicle exhaust decrease with the height increase.The diurnal and height variations of sources reflect the emission and transport characteristics of atmospheric CO2 in Jiading district of Shanghai.

Number concentrations of particulate matters with different diameters(mass medium diameter: 0.03,0.06,0.11,0.17,0.26,0.40,0.65,1.00,1.60,2.50,4.40,6.80 μm) were on-line monitored using an ELPI(electrical low pressure impactor) during 2009 Spring Festival in Jiading District,a suburb area in Shanghai.Several chemical components including 17 elements,10 ions,organic and elemental carbon in particulate matters with different diameters(0.49,0.49—0.95,0.95—1.50,1.50—3.00,3.00—7.20,7.20 μm) were further determined.These particulate matters were collected on both the Spring Festival and ordinary days on the same sampling site.Experimental results showed that the influence of Festival Spring on the number concentrations was mainly on the particulate matters with size range of 0.11— 1.60 μm.If the particulate matters are divided into fine(≤3.00 μm) and coarse(3.00 μm) ones by the diameter of 3.00 μm,it can be seen that the trace elements of Na,As and Pb in fine particulates were greatly affected by the Spring Festival and such effects appeared mainly in the particulate matter with size of 0.49 μm.The trace elements of Ni,Co in coarse particles with size of 7.20 μm were affected by the Spring Festival while Ca,V,Mn,Fe,Zn,Se didn′t show significant effect of the Spring Festival.F-,SO2-4,NH+4,K+,Mg2+ in both fine and coarse particulates were influenced by the Spring Festival.K+ and Mg2+ were influenced seriously in fine particles,and Cl-,NO-3,Na+,NO-2 and Ca2+ in coarse particles were influenced.The OC and EC were much higher in TSP during the Spring Festival than those on ordinary days,and the increases mainly occurred in the fine particles.

With the continue improvement of atmospheric environment in Mega-City,the atmospheric conditions of the surrounding satellite city has received wide public concern.In the present study,both the number and mass weighted size distributions of fine particles(0.03-2.50 μm) in Taicang,a satellite city surrounding Shanghai,were online determined by ELPI.The source analysis was conducted by using mass concentrations and enriched factors of 15 trace elements(Ca,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Sr,Cd,Pb) in the PM2.5.Results show that the concentrations of airborne fine particles in Taicang were higher in night than in daytime.The number weighted size distributions clearly showed a unimodal mode,while the mass weighted size distributions was bimodal distributed.The concentrations of monitored elements,except for Se,in PM2.5 in Taicang were lower than that in other nearby cities,but the enriched factors of Ca,Ti,V,Mn,Ni,Cu,Zn,As,Se,Sr and Pb were relative high.The source analysis showed that those main enriched elements(such as Ca,Ni,Zn,As,Se,Cd,Pb) of PM2.5 in Taicang were affected by urban construction and small-scale processing enterprises.

The concentration of airborne particles (0.03–4.4 µm) in clear and haze days in Shanghai was online investigated by ELPI (electrical low pressure impactor). The concentration of typical elements (K, Ca, Ti, Mn, Cr, Ni, Cu, S, Cl, Zn, As, Pb, Fe) was measured by synchrotron radiation X-ray fluorescence. In this work, Fe was used as the reference element to demonstrate the enrichment of other elements. Experimental results show that, the concentration of airborne particles appeared bi-modal in haze days while appeared single modal in clear days. Also, the particle number concentration showed more remarkable peaks in size segregated particles (0.07–0.3 µm) in haze days than in clear days. Ca, Ti, Cl, Mn, Cr, Zn, As, Pb exhibited single modal in clear days and exhibited bi-modal in haze days; K exhibited single modal in clear and haze days; Cu, S exhibited bimodal in clear and haze days; Ni exhibited bi-modal in clear days and exhibited tri-modal in haze days; Cu, S, Ni showed prominent differences in clear and haze days. For the reason that the enrichment factors of K, Ca, Ti, Mn, Cr were less than 10, they were mainly from natural sources. The enrichment factors of Cl, Pb, As, Ni, Cu, S, Zn were much larger than 10 in clear and haze days, and also the enrichment factors of Ni, Cu, S, Zn were obviously larger in haze days than in clear days.

Atmospheric visibility becomes an important indicator of regional atmospheric environment study,and the effects of atmospheric particles on visibility are significantly different because of their different sizes.The daily mass and number concentrations for atmospheric particles of different sizes were monitored from November 2008 to January 2009 in Jiading district of Shanghai.The visibility was also collected synchronously in the same region.Correlations of the mass concentration for atmospheric particles of different sizes with horizontal visibility and extinction coefficient of particles were analyzed.The results indicate that the effects of atmospheric particles with 0.40 μm and 0.65 μm medium diameters on horizontal visibility are significant,so is with 0.17 μm,0.26 μm,0.40 μm and 0.65 μm medium diameters on extinction coefficient.The distributions of correlation coefficients are consistent with size distributions of five components(SO2-4,NO-3,NH+4,OC and EC) of atmospheric particles,which suggests that five components may be the important influencing factors of extinction coefficient.

The concentration of airborne particles (0.03–4.4 µm) in clear and haze days in Shanghai was online investigated by ELPI (electrical low pressure impactor). The concentration of typical elements (K, Ca, Ti, Mn, Cr, Ni, Cu, S, Cl, Zn, As, Pb, Fe) was measured by synchrotron radiation X-ray fluorescence. In this work, Fe was used as the reference element to demonstrate the enrichment of other elements. Experimental results show that, the concentration of airborne particles appeared bi-modal in haze days while appeared single modal in clear days. Also, the particle number concentration showed more remarkable peaks in size segregated particles (0.07–0.3 µm) in haze days than in clear days. Ca, Ti, Cl, Mn, Cr, Zn, As, Pb exhibited single modal in clear days and exhibited bi-modal in haze days; K exhibited single modal in clear and haze days; Cu, S exhibited bimodal in clear and haze days; Ni exhibited bi-modal in clear days and exhibited tri-modal in haze days; Cu, S, Ni showed prominent differences in clear and haze days. For the reason that the enrichment factors of K, Ca, Ti, Mn, Cr were less than 10, they were mainly from natural sources. The enrichment factors of Cl, Pb, As, Ni, Cu, S, Zn were much larger than 10 in clear and haze days, and also the enrichment factors of Ni, Cu, S, Zn were obviously larger in haze days than in clear days.

Size distributions of 9 water –soluble ions (SO42-、NO3-、NH4+、K+、Na+、Cl - 、Ca2+、Mg2+、F - ) in atmospheric particles of Shanghai were determined. SO42-、NO3- and NH4+ contributed 65%～81% of mass concentrations of the total ions. The average ratios of cations/anions (C/A) of the particles were 1.08, close to unity, indicating that particles were a bit more alkaline, which may be relative to the lack of determination of carbonate and so on. Mass concentrations of the ions focused in the particles with size of 1.5μm, which accounted for 52%～87% of those in the total suspended particles. Size distributions of NH4+and K+ showed mono-modals with the peak at the particle size of 0.95μm, SO42-、NO3-、Ca2+、 Cl- appeared bi-modals with peaks at the particle sizes of 0.95μm and 3.0～7.2μm, respectively. SO42-、NO3- were preferably enriched in the particles with size of 0.95μm, while Ca2+ in the particles with size of 3.0μm. Cl - appeared equal values in either of the two peaks. Na+、Mg2+ and F- showed both of bi-modals and mono-modals, and they were preferably enriched in the particles with size of 3.0μm. The size distributions of these ions depended on the meteorological conditions, formation mechanisms and sources.

Size distributions of organic carbon (OC), elemental carbon (EC) and secondary organic carbon (SOC) in atmospheric particles with size range from < 0.49, 0.49-0.95, 0.95-1.50, 1.50-3.00, 3.00-7.20, > 7.20 microm, collected in Jiading District, Shanghai were determined. For estimating size distribution of SOC in these atmospheric particles, a method of determining (OC/EC)(pri) in atmospheric particles with different sizes was discussed and developed, with which SOC was estimated. According to the correlation between OC and EC, main sources of the particles were also estimated roughly. The size distributions of OC and SOC showed a bi-modal with peaks in the particles with size of < 0.49 microm and > 3.0 microm, respectively. EC showed both of a bi-modal and tri-modal. Compared with OC, EC was preferably enriched in particles with size of < 0.49 microm. Mass concentrations of OC and EC in fine particles (< 3.00 microm) accounted for 59.8%-80.0% and 58.1%-82.4% of those in total suspended particles. OC and EC were preferably enriched in fine particles (< 3.00 microm). The concentrations of SOC in the particles with different sizes accounted for 15.7%-79.1% of OC in the particles with corresponding size. Concentrations of SOC in fine aerosols (< 3.00 microm) and coarse aerosols (> 3.00 microm) accounted for 41.4% and 43.5% of corresponding OC. Size distributions of OC, EC and SOC showed time-dependence. The correlation between OC and EC showed that the main contribution to atmospheric particles in Jiading District derived from light petrol vehicles exhaust.