Two types of modified silica gels were prepared by adsorption method and bonding method respectively. Enrichment and separation of trace metal ions have been done by using the column packed with modified silica gels.
Glass-plate sampling during 1988-1999 in Daya Bay and suitable corresponding analytical methods were used for the measurement of dissolved trace metals, dissolved organic carbon, biological oxygen demand, chemical oxy...Glass-plate sampling during 1988-1999 in Daya Bay and suitable corresponding analytical methods were used for the measurement of dissolved trace metals, dissolved organic carbon, biological oxygen demand, chemical oxygen demand, salinity of the sea surface microlayer and subsurface water. Apparent enrichment mechanism and diurnal variation have been revealed for dissolved trace metals in the microlayer in Daya Bay. The more dissolved organic matter was enriched in the sea surface microlayer, the more dissolved trace metals were enriched in the layer. The organic matter played an important role in the enrichment process. The diurnal variations of dissolved trace metals showed that their concentration was apparently inversely related to the tide activity that the concentration was low during rising tide, but high during falling tide. The behavior of dissolved trace metals expressed by the diurnal variation was clearly opposite to that of salinity.展开更多
Trace metals in PM2.5 were measured at one industrial site and one urban site during September, 2010 in Ji＇nan, eastern China. Individual aerosol particles and PM2.5 samples were collected concurrently at both sites....Trace metals in PM2.5 were measured at one industrial site and one urban site during September, 2010 in Ji＇nan, eastern China. Individual aerosol particles and PM2.5 samples were collected concurrently at both sites. Mass concentrations of eleven trace metals （i.e., Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, and Pb） and one metalloid （i.e., As） were measured by inductively coupled plasma atomic emission spectroscopy （ICP-AES）. The result shows that mass concentrations of PM2.5 （130μg/m3） and trace metals （4.03 μg/m3） at the industrial site were 1.3 times and 1.7 times higher than those at the urban site, respectively, indicating that industrial activities nearby the city can emit trace metals into the surrounding atmosphere. Fe concentrations were the highest among all the measured trace metals at both sites, with concentrations of 1.04 ixg/m 3 at the urban site and 2.41 Itg/m3 at the industrial site, respectively. In addition, Pb showed the highest enrichment factors at both sites, suggesting the emissions from anthropogenic activities existed around the city. Correlation coefficient analysis and principal component analysis revealed that Cu, Fe, Mn, Pb, and Zn were originated from vehicular traffic and industrial emissions at both sites; As, Cr, and part of Pb from coal-fired power plant; Ba and Ti from natural soil. Based on the transmission electron microscopy analysis, we found that most of the trace metals were internally mixed with secondary sulfate/organic particles. These internally mixed trace metals in the urban air may have different toxic abilities compared with externally mixed trace metals.展开更多
文摘Two types of modified silica gels were prepared by adsorption method and bonding method respectively. Enrichment and separation of trace metal ions have been done by using the column packed with modified silica gels.
文摘Glass-plate sampling during 1988-1999 in Daya Bay and suitable corresponding analytical methods were used for the measurement of dissolved trace metals, dissolved organic carbon, biological oxygen demand, chemical oxygen demand, salinity of the sea surface microlayer and subsurface water. Apparent enrichment mechanism and diurnal variation have been revealed for dissolved trace metals in the microlayer in Daya Bay. The more dissolved organic matter was enriched in the sea surface microlayer, the more dissolved trace metals were enriched in the layer. The organic matter played an important role in the enrichment process. The diurnal variations of dissolved trace metals showed that their concentration was apparently inversely related to the tide activity that the concentration was low during rising tide, but high during falling tide. The behavior of dissolved trace metals expressed by the diurnal variation was clearly opposite to that of salinity.
基金supported by the National Basic Research Program(973)of China(No.2011CB403401)the National Natural Science Foundation of China(No.41105088,41275141)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2011DQ001)the State Key Laboratory for Coal Resources and Safe Mining(No.SKLCRSM11KFB03)
文摘Trace metals in PM2.5 were measured at one industrial site and one urban site during September, 2010 in Ji＇nan, eastern China. Individual aerosol particles and PM2.5 samples were collected concurrently at both sites. Mass concentrations of eleven trace metals （i.e., Al, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, and Pb） and one metalloid （i.e., As） were measured by inductively coupled plasma atomic emission spectroscopy （ICP-AES）. The result shows that mass concentrations of PM2.5 （130μg/m3） and trace metals （4.03 μg/m3） at the industrial site were 1.3 times and 1.7 times higher than those at the urban site, respectively, indicating that industrial activities nearby the city can emit trace metals into the surrounding atmosphere. Fe concentrations were the highest among all the measured trace metals at both sites, with concentrations of 1.04 ixg/m 3 at the urban site and 2.41 Itg/m3 at the industrial site, respectively. In addition, Pb showed the highest enrichment factors at both sites, suggesting the emissions from anthropogenic activities existed around the city. Correlation coefficient analysis and principal component analysis revealed that Cu, Fe, Mn, Pb, and Zn were originated from vehicular traffic and industrial emissions at both sites; As, Cr, and part of Pb from coal-fired power plant; Ba and Ti from natural soil. Based on the transmission electron microscopy analysis, we found that most of the trace metals were internally mixed with secondary sulfate/organic particles. These internally mixed trace metals in the urban air may have different toxic abilities compared with externally mixed trace metals.
