Zhang Z.,South China Institute of Environmental Sciences |
Tao J.,South China Institute of Environmental Sciences |
Xie S.,Peking University |
Zhou L.,Chengdu Academy of Environmental Protection |
And 4 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2013
Daily PM2.5 samples were collected from 2009 to 2010 during a typical month of each season at an urban site of Chengdu. The mass concentration and chemical compositions (including carbonaceous species, water-soluble inorganic ions and elements) of PM2.5 were determined. The results showed that the average PM2.5 mass concentration was (165.1±85.1) μg·m-3, which was 4.7 times the annual PM2.5 National Ambient Air Quality Standard of China. The average concentrations of OC, EC and total secondary inorganic ions (SO4 2-, NO3 - and NH4 +) were (22.6±10.2) μg·m-3, (9.0±5.4) μg·m-3 and (62.8±44.3) μg·m-3, accounting for 13.7%, 5.5% and 38.0% of PM2.5 mass concentration, respectively. Higher levels of PM2.5 mass concentration and their major chemical compositions were found in autumn and winter compared to those found in spring and summer. Positive Matrix Factorization (PMF) model was performed to identify the sources of PM2.5 at urban Chengdu. Four sources significantly contributing to the observed PM2.5 were: soil dust and fugitive dust, biomass burning, vehicle emissions and secondary nitrate/sulfate, with the contributions of 14.3%, 28.0%, 24.0% and 31.3% to PM2.5 mass concentration, respectively. These four sources exhibited distinct seasonal patterns: the relative contribution of biomass burning to total PM2.5 was relatively high for all seasons; the relative contribution of soil dust and fugitive dust increased significantly during spring; vehicle emissions contributed significantly during summer; and the highest relative contribution to PM2.5 during autumn and winter was secondary nitrate/sulfate factor.
Jia B.-Y.,University of Sichuan |
Jia B.-Y.,Chengdu Academy of Environmental Protection |
Fu W.-L.,Environmental Monitoring Station of Jianyang City |
Yu J.,Chengdu University of Technology |
And 2 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2013
Based on the 210Pb and 137Cs dating, the article analyzes the vertical and lateral changes in their physical and chemical features that have happened to the lake sediment in Sancha Lake in Sichuan Province, Southwestern China. It shows the changes of Sancha Lake sediment contents and deposition rates are closely related to human activities and lake eutrophication progress. The changes of total nitrogen (TN), total phosphorus (TP) and total organic carbon (TOC) concentrations in the lake sediment strongly coincide with that of Sancha Lake water quality. When the reservoir was first built, the lake water was in an oligotrophic state. As human activities increased, the water quality started to deteriorate and continued to do so. Human activities such as manufacturing, farming, fishing, and tourism have accelerated the eutrophication of Sancha Lake. The key to improve the water quality lies in limiting human activities. The most important source of phosphorus in sediment is from cage culture. It takes a very long time for the phosphorus concentration in the sediment to actually go down after such practices cease.
Xiao X.,Shandong University of Science and Technology |
Zhang Q.,Shandong University of Science and Technology |
Tian Y.,Shandong University of Science and Technology |
Wang Z.,Chengdu Academy of Environmental Protection
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011 - Proceedings | Year: 2011
An automatic, convenient method combined flow injection technique for determining organic phosphorus pesticide in environment water was developed based on the inhibition effects of organic phosphorus pesticide to plant-esterase. The optimized determining conditions were acquired, and the analytical characteristics of this method were studied. The linear ranges of dichlorvos' standard curves was 0.008 ∼ 4mg/L. The linear equation of dichlorvos was U(mV) =-4874.4 C (mg/L) + 110313. The correlation coefficient of dichlorvos was 0.9984. The detection limit (S/N= 3) was 0.02mg/L for dichlorvos. The relative standard deviation (RSD) of dichlorvos was 1.04% (n=6). The recoveries ranged from 95% to 105%. The analysis result was good. © 2011 IEEE.
Xiao X.-F.,Shandong University of Science and Technology |
Yang N.,Shandong University of Science and Technology |
Wang Z.-L.,Chengdu Academy of Environmental Protection |
Huang Y.-Q.,Shandong University of Science and Technology
Analytical Methods | Year: 2016
An on-line flow-injection spectrophotometric method coupled with supported liquid membrane enrichment was developed to determine trace Hg(ii) in water. Tributyl phosphate (TBP) dissolved in kerosene was used as the flow carrier in a supported liquid membrane extraction system. The effect of various parameters on Hg(ii) measurement was investigated. The optimum conditions were determined as 20% TBP in the membrane phase, 0.02 mol L-1 NaOH in the accepting phase, 0.8 mol L-1 HCl in the feeding phase, 0.2 μm PTFE membrane in the enrichment process, and 20 min enrichment time. Under these optimum conditions, the linear range for Hg(ii) measurement was from 0.2 to 30 μg L-1 with a detection limit of 0.06 μg L-1. Additionally, we demonstrated that this system can be used to determine trace Hg(ii) in wastewater. © 2016 The Royal Society of Chemistry.