Aerosol observation was conducted for four seasons from September 2001 to August 2002 at five sampling sites in Hangzhou, South China, on PM10 mass, 22 elements （Na, Mg, AI, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu...Aerosol observation was conducted for four seasons from September 2001 to August 2002 at five sampling sites in Hangzhou, South China, on PM10 mass, 22 elements （Na, Mg, AI, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As. Se, Br, Cd, Ba, and Pb）, 5 major ions （F^-, Cl^ , NO3^-, SO4^2- , and NH4^＋）, and organic and elemental carbon （OC and EC）, showing that PM10 mass ranged from 46.7 to 270.8 μg/m^3, with an annual average of 119.2 μg/m^3. Na, AI, Si, S, K, Ca, and Fe were the most abundant elements in PM10, most of S being in the form of SO4^2- . SO4^2-, NO3^-, and NH4^＋ were the major ions, which contributed to about 20% of the PM10 mass. The mean seasonal concentrations for SO4^2- , averaged over all sites, were found to be 18.0, 18.5, 24,Z and 21.4 μg/m^3, for spring, summer, autumn, and winter, respectively, while the corresponding loadings for NO3^- were 7.2, 4.7, 7.1, and 11.2 μg/m^3, and for NH4^＋ were 6.0, 5.9, 8.2, and 9.3 μg/m^3, in the form mostly of NH4NO3 in spring, autumn, and winter, and mostly of （NH4）2SO4 in summer. The low NO3^-/SO4^2- ratio found indicates coal combustion as the major source throughout the year. The mean annual concentrations of OC and EC in PM10 were found to be 21.4, and 4.1 μg/m^3, respectively. Material balance calculation indicated that fugitive dust, the secondary aerosol, and carbonaceous matter were the most abundant species in PM10 for the four seasons, as is characteristic for cities in South China.展开更多
Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, ...Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, and Cu in PM10 samples, were determined using atomic absorption spectrometer （AAS）. Beta attenuation method was applied to observe the hourly variation of PM10 levels. Results show that average PM10 concentrations at the entrance and at the exit were 101.3 μg/m3 and 234.4 μg/m3, respectively, and average PM2.5 concentrations at the entrance and at the exit were 47.7 μg/m3 and 62.7μg/m3, respectively. PM pollution was worse at the exit than at the entrance. Hourly PMlo concentration was weakly correlated with traffic flow. Regarding element concentrations, the most enriched element in PM10 samples was Fe. Re-suspension of soil dust at the exit is an important source of PM10.展开更多
基金supported by the National Natural Science Foun-dation of China (Grants 40675081 and 40599422)
文摘Aerosol observation was conducted for four seasons from September 2001 to August 2002 at five sampling sites in Hangzhou, South China, on PM10 mass, 22 elements （Na, Mg, AI, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As. Se, Br, Cd, Ba, and Pb）, 5 major ions （F^-, Cl^ , NO3^-, SO4^2- , and NH4^＋）, and organic and elemental carbon （OC and EC）, showing that PM10 mass ranged from 46.7 to 270.8 μg/m^3, with an annual average of 119.2 μg/m^3. Na, AI, Si, S, K, Ca, and Fe were the most abundant elements in PM10, most of S being in the form of SO4^2- . SO4^2-, NO3^-, and NH4^＋ were the major ions, which contributed to about 20% of the PM10 mass. The mean seasonal concentrations for SO4^2- , averaged over all sites, were found to be 18.0, 18.5, 24,Z and 21.4 μg/m^3, for spring, summer, autumn, and winter, respectively, while the corresponding loadings for NO3^- were 7.2, 4.7, 7.1, and 11.2 μg/m^3, and for NH4^＋ were 6.0, 5.9, 8.2, and 9.3 μg/m^3, in the form mostly of NH4NO3 in spring, autumn, and winter, and mostly of （NH4）2SO4 in summer. The low NO3^-/SO4^2- ratio found indicates coal combustion as the major source throughout the year. The mean annual concentrations of OC and EC in PM10 were found to be 21.4, and 4.1 μg/m^3, respectively. Material balance calculation indicated that fugitive dust, the secondary aerosol, and carbonaceous matter were the most abundant species in PM10 for the four seasons, as is characteristic for cities in South China.
基金supported by the Fundamental Research Funds for the Central Universities of China(Grant No. 2011PY049)
文摘Particulate matter （PM） pollution in an underground car park in Wuhan was investigated. Mass concentrations of PM10 and PM2.5 were obtained using gravimetric method. Selected metal elements, such as Fe, Mn, Zn, Pb, and Cu in PM10 samples, were determined using atomic absorption spectrometer （AAS）. Beta attenuation method was applied to observe the hourly variation of PM10 levels. Results show that average PM10 concentrations at the entrance and at the exit were 101.3 μg/m3 and 234.4 μg/m3, respectively, and average PM2.5 concentrations at the entrance and at the exit were 47.7 μg/m3 and 62.7μg/m3, respectively. PM pollution was worse at the exit than at the entrance. Hourly PMlo concentration was weakly correlated with traffic flow. Regarding element concentrations, the most enriched element in PM10 samples was Fe. Re-suspension of soil dust at the exit is an important source of PM10.
