[Objective] This study was conducted to investigate soil heavy metal Pb pol ution level and spatial distribution characteristics at two sides of arterial traffic in Yel ow River delta area. [Method] Soil samples were ...[Objective] This study was conducted to investigate soil heavy metal Pb pol ution level and spatial distribution characteristics at two sides of arterial traffic in Yel ow River delta area. [Method] Soil samples were col ected by sample-plot sur-vey method, and soil Pb pol ution condition in road area of Yel ow River delta was determined and analyzed by atomic absorption spectrometry. [Result] Pb pol ution at two sides of national road G205 and provincial road S312 was mainly from auto-mobile exhaust, and Pb content in soil decreased with the distance from road in-creasing. Soil samples col ected at points with distances in the range of 1-50 m from truck road of G205 was 32.46-86.04 mg/kg, which was 1.2-3.3 times of soil Pb background value in this area, and the pol ution was more remarkable. Further study showed that green belt aside road could effectively reduce soil Pb pol ution level. [Conclusion] This study provides theoretical basis and basic information for in-vestigation of soil heavy metal Pb pol ution level and spatial distribution characteris-tics at two sides of arterial traffic in Yel ow River delta area.展开更多
The horizontal and vertical distribution characteristics of Pb in urban soil of Shenyang City, China were investigated in this study. The range of Pb concentration in the soil was 22.02-2910.60mg/kg. The standard devi...The horizontal and vertical distribution characteristics of Pb in urban soil of Shenyang City, China were investigated in this study. The range of Pb concentration in the soil was 22.02-2910.60mg/kg. The standard deviation was 443.07mg/kg, and coefficient of variation was 1.64. Tiexi District was seriously contaminated by lead. In general, Pb concentration in the soil decreased with distance from pollution source. Lead concentration varied in different functional areas with the order of industrial area>commercial area>residential area>suburb>reference area. Pb concentration decreased with the depth of soil profile. Both geo-accumulation index and ecological risk index were used to estimate the potential risk of soil Pb pollution in Shenyang City. The results showed that the high potential risk area included Tiexi District and traffic roads.展开更多
Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synt...Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synthesized Pt-Pb hexagonal nanoplates as a model catalyst for the methanol oxidation reaction(MOR) and further controlled the Pt and Pb distributions on the surface of the nanoplates through acetic acid(HAc) treatment. As a result, we obtained Pt-Pb nanoplates and HAc-treated Pt-Pb nanoplates with homogeneous and heterogeneous distributions of the Pt-Pb alloy surfaces, respectively. We showed that the MOR activity and stability of the Pt-Pb nanoplates improved compared to those of the HAc-treated Pt-Pb nanoplates, mainly due to the enhanced CO tolerance and the modified electronic structure of Pt under the influence of the oxophilic Pb.展开更多
基金Supported by Scientific Research Development Planning Project of Education Department of Shandong Province(J08LD51)~~
文摘[Objective] This study was conducted to investigate soil heavy metal Pb pol ution level and spatial distribution characteristics at two sides of arterial traffic in Yel ow River delta area. [Method] Soil samples were col ected by sample-plot sur-vey method, and soil Pb pol ution condition in road area of Yel ow River delta was determined and analyzed by atomic absorption spectrometry. [Result] Pb pol ution at two sides of national road G205 and provincial road S312 was mainly from auto-mobile exhaust, and Pb content in soil decreased with the distance from road in-creasing. Soil samples col ected at points with distances in the range of 1-50 m from truck road of G205 was 32.46-86.04 mg/kg, which was 1.2-3.3 times of soil Pb background value in this area, and the pol ution was more remarkable. Further study showed that green belt aside road could effectively reduce soil Pb pol ution level. [Conclusion] This study provides theoretical basis and basic information for in-vestigation of soil heavy metal Pb pol ution level and spatial distribution characteris-tics at two sides of arterial traffic in Yel ow River delta area.
基金Under the auspices of the National Natural Science Foundation of China (No. 40171089), Knowledge InnovationProgram of Chinese Academy of Sciences (No. KZCX1-SW-19-4-01) and National Basic Research Program of China (No.2004CB418507)
文摘The horizontal and vertical distribution characteristics of Pb in urban soil of Shenyang City, China were investigated in this study. The range of Pb concentration in the soil was 22.02-2910.60mg/kg. The standard deviation was 443.07mg/kg, and coefficient of variation was 1.64. Tiexi District was seriously contaminated by lead. In general, Pb concentration in the soil decreased with distance from pollution source. Lead concentration varied in different functional areas with the order of industrial area>commercial area>residential area>suburb>reference area. Pb concentration decreased with the depth of soil profile. Both geo-accumulation index and ecological risk index were used to estimate the potential risk of soil Pb pollution in Shenyang City. The results showed that the high potential risk area included Tiexi District and traffic roads.
文摘Bimetallic Pt-based catalysts have been extensively investigated to enhance the performance of direct methanol fuel cells(DMFCs) because CO, a by-product, reduces the activity of the pure Pt catalysts. Herein, we synthesized Pt-Pb hexagonal nanoplates as a model catalyst for the methanol oxidation reaction(MOR) and further controlled the Pt and Pb distributions on the surface of the nanoplates through acetic acid(HAc) treatment. As a result, we obtained Pt-Pb nanoplates and HAc-treated Pt-Pb nanoplates with homogeneous and heterogeneous distributions of the Pt-Pb alloy surfaces, respectively. We showed that the MOR activity and stability of the Pt-Pb nanoplates improved compared to those of the HAc-treated Pt-Pb nanoplates, mainly due to the enhanced CO tolerance and the modified electronic structure of Pt under the influence of the oxophilic Pb.
