Mass concentrations of Total Suspended Particles （TSP） and size-segregated particles were obtained from July 2001 to June 2002 in Qingdao to characterize the seasonal variations of atmospheric aerosols and to show t...Mass concentrations of Total Suspended Particles （TSP） and size-segregated particles were obtained from July 2001 to June 2002 in Qingdao to characterize the seasonal variations of atmospheric aerosols and to show the impact of dust events on the air quality in Qingdao. Data on size-segregated aerosols show that 73.74% of the TSP mass concentration is contributed by particles with diameters less than 11 μm. Particles with diameters less than 1.1μm have a higher concentration during the winter. In spring, larger particles tend to have higher mass concentrations. Bimodal particle size distributions have been observed, with maxima around 4.7-7 μand 0.43-0.65 μm in the winter season, and 7-11 μm and 0.65-1.1 μm in the autumn season. Measurements made during the dust events in March 2002 show high concentrations of particles in the size range 2.1-7μm.展开更多
This paper has demonstrated that there is great variation in the size range and chemical composition of metalliferous PM （particulate matter） present within Comarca Lagunera, M6xico due to the physiography of the te...This paper has demonstrated that there is great variation in the size range and chemical composition of metalliferous PM （particulate matter） present within Comarca Lagunera, M6xico due to the physiography of the terrain together the intense vehicular traffic, unpaved roads, cement and lime plants, marble quarries, brick plants, and the largest smelter of non-ferrous material in Latin America. Cascade impactor PM samples from six size ranges： 〈 0.49 μm, 0.49-0.9 μm, 0.9-1.5μm, 1.5-3.0 p.m, 3.0-7.2 μm and 7.2-10 μm were collected from inside two stacks within G6mez Palacios and Torreon cities. ICP-AES （inductively coupled plasma-atomic emission spectrometry） analysis on collected Whatman fiberglass filters demonstrates that the PM are matrices mostly constituted of carbonates and silicates with abundant fine metalliferous particles. The metals with the most concentrations averaged over all size ranges were Cu, Fe, Mn, Ni, Pb and Ti. The size distributions of metals detected in this work have been plotted as normalized histogram concentration of each size fraction, the total concentration, and the aerodynamic particle diameter, which is a useful method for comparing the contributions of coarse and fine particles to pollutant concentrations.展开更多
The mass concentration and size distribution of aerosols in Tokaimura were investigated using a high-volume and a low-volume Andersen sampler. A difference was found using the two samplers： the concentration of total...The mass concentration and size distribution of aerosols in Tokaimura were investigated using a high-volume and a low-volume Andersen sampler. A difference was found using the two samplers： the concentration of total aerosols determined with the high-volume sampler is smaller than that of the low-volume sampler by 70-90% throughout the year. Compared to the high-volume sampler, low-volume sampler gave lower concentration for aerosols 〉7 μm, higher concentration for aerosols of 3.3-7.0 μm and 〈 1.1 μm, though similar results for aerosols of 1.1-3.3 μm. The low-volume sampler was found to have better separation efficiency and higher accuracy.展开更多
基金This study is supported by National Natural Science Foundation of China(No.40490262).
文摘Mass concentrations of Total Suspended Particles （TSP） and size-segregated particles were obtained from July 2001 to June 2002 in Qingdao to characterize the seasonal variations of atmospheric aerosols and to show the impact of dust events on the air quality in Qingdao. Data on size-segregated aerosols show that 73.74% of the TSP mass concentration is contributed by particles with diameters less than 11 μm. Particles with diameters less than 1.1μm have a higher concentration during the winter. In spring, larger particles tend to have higher mass concentrations. Bimodal particle size distributions have been observed, with maxima around 4.7-7 μand 0.43-0.65 μm in the winter season, and 7-11 μm and 0.65-1.1 μm in the autumn season. Measurements made during the dust events in March 2002 show high concentrations of particles in the size range 2.1-7μm.
文摘This paper has demonstrated that there is great variation in the size range and chemical composition of metalliferous PM （particulate matter） present within Comarca Lagunera, M6xico due to the physiography of the terrain together the intense vehicular traffic, unpaved roads, cement and lime plants, marble quarries, brick plants, and the largest smelter of non-ferrous material in Latin America. Cascade impactor PM samples from six size ranges： 〈 0.49 μm, 0.49-0.9 μm, 0.9-1.5μm, 1.5-3.0 p.m, 3.0-7.2 μm and 7.2-10 μm were collected from inside two stacks within G6mez Palacios and Torreon cities. ICP-AES （inductively coupled plasma-atomic emission spectrometry） analysis on collected Whatman fiberglass filters demonstrates that the PM are matrices mostly constituted of carbonates and silicates with abundant fine metalliferous particles. The metals with the most concentrations averaged over all size ranges were Cu, Fe, Mn, Ni, Pb and Ti. The size distributions of metals detected in this work have been plotted as normalized histogram concentration of each size fraction, the total concentration, and the aerodynamic particle diameter, which is a useful method for comparing the contributions of coarse and fine particles to pollutant concentrations.
基金partly supported by National Natural Science Foundation of China(NSFC,40575066)Japan Society for the Promotion of Science(JSPS).
文摘The mass concentration and size distribution of aerosols in Tokaimura were investigated using a high-volume and a low-volume Andersen sampler. A difference was found using the two samplers： the concentration of total aerosols determined with the high-volume sampler is smaller than that of the low-volume sampler by 70-90% throughout the year. Compared to the high-volume sampler, low-volume sampler gave lower concentration for aerosols 〉7 μm, higher concentration for aerosols of 3.3-7.0 μm and 〈 1.1 μm, though similar results for aerosols of 1.1-3.3 μm. The low-volume sampler was found to have better separation efficiency and higher accuracy.
