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Chen Y.,Capital University of Economics and Business | Xie S.-D.,Peking University | Luo B.,Sichuan Provincial Environmental Monitoring Center | Zhai C.-Z.,Chongqing Environmental Monitoring Center
Science of the Total Environment | Year: 2017

Chongqing, the largest megacity in southwest China, faces serious aerosol pollution but lacks information on particle characteristics and its sources. Official data released by Chongqing Environmental Protection Bureau demonstrated that urban PM10 concentrations decreased remarkably from 150 μg m− 3 in 2000 to 90 μg m− 3 in 2012. However, only several peer-reviewed studies paid attention to local fine particle (PM2.5) pollution. In the study, PM2.5 samples were obtained and subjected to chemical analysis in an urban site of the city during 2012 to 2013. The annual mean PM10 and PM2.5 concentrations in urban Chongqing were 103.9 ± 52.5 and 75.4 ± 42.2 μg m− 3, respectively. PM2.5 showed a distinct seasonality of high concentration in winter and similar levels in other seasons. The average OC/EC (organic carbon/element carbon) ratio was 3.7 with more high-OC/EC ratio sources contribution in autumn and winter. The varying sources and formation mechanisms resulted in SO4 2 − and NH4 + peaks in both summer and winter, whereas high nitrate concentration was only observed in winter. In the average mass closure, PM2.5 was composed of 23.0% SO4 2 −, 11.7% NO3 −, 10.9% NH4 +, 30.8% OM (organic matter), 5.2% EC, 8.2% mineral dust, 0.6% TEO (trace elements), 1.0% Cl− and 1.1% K+, while exhibiting large seasonal variability. Using positive matrix factorization (PMF), six sources were apportioned in PM2.5: secondary inorganic aerosols, coal combustion, other industrial pollution, soil dust, vehicular emission, and metallurgical industry. The annual mean contribution of above sources to PM2.5 was 37.5, 22.0, 17.5, 11.0, 9.8 and 2.2%, respectively. Coal combustion was identified by As tracer and dominated the primary sources of PM2.5, while the two different industrial sources were characterized by Cr and Mo, Co, Ni, and Se, respectively. The study is of great importance in characterizing the historical trends, current chemical characteristics and sources of fine particles in urban Chongqing. © 2017 Elsevier B.V.


PubMed | Capital University of Economics and Business, Peking University, Chongqing Environmental Monitoring Center and Sichuan Provincial Environmental Monitoring Center
Type: | Journal: The Science of the total environment | Year: 2017

Chongqing, the largest megacity in southwest China, faces serious aerosol pollution but lacks information on particle characteristics and its sources. Official data released by Chongqing Environmental Protection Bureau demonstrated that urban PM


PubMed | Environment Canada, Chongqing Environmental Monitoring Center and CAS Chongqing Institute of Green and Intelligent Technology
Type: | Journal: The Science of the total environment | Year: 2016

To investigate the characteristics of water-soluble inorganic ions (WSIIs) in Chongqing, a well-known foggy and acid region in southwestern China, hourly real-time concentrations of five cations (Na


Cheng Z.,Chongqing University of Technology | Xiong Y.,Chongqing Environmental Monitoring Center | Quan X.,Chongqing University of Technology
Key Engineering Materials | Year: 2016

A sequential ultrasound intensified photocatalytic reactors was investigated to degrade and mineralize typical endocrine disruptor, bisphenol A (BPA) using nanometer TiO2 as photocatalyst. The process parameters i.e., US power, TiO2 dosages, air flow rate and circulating liquid velocity of the reactors were optimized of the process. Under the optimum operation condition, nearly 90% and 80% BPA was degraded and mineralized in the reactor within 2.5 h. The combination of sonolysis and photocatalysis of TiO2 exhibits a synergetic effect, and benefits for BPA mineralization. © 2016 Trans Tech Publications, Switzerland.


Liang A.,Chongqing Academy of Environmental Science | Wang Y.,Chongqing Academy of Environmental Science | Guo H.,Chongqing Academy of Environmental Science | Bo L.,Chongqing Academy of Environmental Science | And 2 more authors.
Environmental Science and Pollution Research | Year: 2015

To assess the heavy metal pollution in Changshou Lake, sediments were collected from nine sites at three periods (dry, normal, and wet) in 2013. The Hg, As, Cr, Cd, Pb, Cu, and Zn levels were then determined. The index of geoaccumulation (Igeo) and the sediment pollution index (SPI) were applied to the sediment assessment, and Pearson’s correlation analysis and factor analysis (FA) were performed to identify common pollution sources in the basin. The results showed that heavy metals presented significant spatial variations with Cr, Cd, Pb, Cu, Zn, Hg, and As concentrations of 29.66~42.58, 0.62~0.91, 24.91~37.96, 21.18~74.91, 41.65~86.86, 0.079~0.152, and 20.17~36.88 mg kg−1, respectively, and no obvious variations were found among the different periods. The average contents of the metals followed the order Zn > Cu > Cr > Pb > As > Cd > Hg, which showed a high pollution in the sediments collected from open water and at the river mouth. The assessment results indicated that toxic heavy metals presented obvious pollution with IHg of 0.64~1.36 (moderately polluted), ICd of 1.66~2.22 (moderately to heavily polluted), and IAs of 1.21~2.07 (moderately to heavily polluted). The heavy metal pollution states followed the order Cd > As > Hg > Cu > Pb > Zn > Cr, and the SPI showed that the sediment collected from open water area was more polluted than those obtained from the tributaries and the river mouth. Cr, Cd, Hg, Pb, Cu, As, and Zn were mainly attributed to sediment weathering with Hg, Pb, and Cu and partially due to domestic sewage from the upper reaches. These results indicate that the more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution. © 2015 Springer-Verlag Berlin Heidelberg


Yang M.,Chongqing Environmental Monitoring Center | Yang M.,Chongqing Academy of Environmental science | Zhang S.,Chongqing Academy of Environmental science | Liu S.-R.,Chongqing Environmental Monitoring Center | Liu S.-R.,Chongqing Academy of Environmental science
Huanjing Kexue/Environmental Science | Year: 2015

The variation of phytoplankton community and the water quality in Jialing River after the impoundment of Caojie Reservoir was studied in this paper. There were 145 species of phytoplankton under the membership of 8 divisions and 74 genera. Bacillariophyta was the first dominant division, with a total of 57 species of 23 genera, accounted for 39.3% of total phytoplankton species, followed by Chlorophyta, with 53 species of 28 genera and accounted for 36.6%. Only 35 species of 23 genera belonged to Euglenphyta, Cryptophyta, Pyrrophyta, Chrysophyta, and Cyanophyta. The average phytoplankton abundance was 1.82×105 cell·L-1, and the top three taxon of most abundant were Bacillariophyta, Cryptophyta and Pyrrophyta, accounted for 39.2%, 29.9%, and 24.5% of total abundance, respectively. The cell abundance in spring was significantly higher than those in other seasons. The dominant species included Aulacoseria granulata, Melosira varians, Peridiniopsis niei, Komma caudata, Cryptomonas erosa etc., indicated by the dominant index. Excluded by cluster analysis, the influence on phytoplankton had initially emerged after the impoundment of Caojie Reservoir. The reservoir area could be divided into different ecological regions longitudinally after Caojie Reservoir impoundment, which had an important impact on the phytoplankton. Meanwhile, the phytoplankton and flow velocity between upstream and downstream of the dam significantly varied. Shannon-Wiener species diversity index, Margalef species richness index and Pielous evenness index ranged 2.06-3.55, 0.76-1.90 and 0.50-0.78, respectively. The evaluation results of phytoplankton community structure showed that the eutrophic state was at medium eutrophication level, while diversity analysis results indicated light to moderate pollution. ©, 2015, Science Press. All right reserved.


Yang S.,Chongqing Institute of Meteorological science | Liu C.,Chongqing Environmental Monitoring Center | Gao Y.,Chongqing Institute of Meteorological science
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

This paper selected 6S (second simulation of the satellite signal in the solar spectrum) model with dark pixel method to inversion aerosol optical depth by MODIS data, and got the spatial distribution and the temporal distribution of Chongqing urban area. By comparing with the sun photometer and API data, the result showed that the inversion method can be used in aerosol optical thickness monitoring in Chongqing urban area. © 2015 SPIE.


Gan W.,Chongqing Environmental Monitoring Center | Liu X.,Chongqing Huineng Biaopu Technology Co. | Sun J.,Chongqing Environmental Monitoring Center
Chinese Journal of Chromatography (Se Pu) | Year: 2015

This paper presents a method of regression evaluation index intelligent filter method (REIFM) for quick optimization of chromatographic separation conditions. The hierarchical chromatography response function was used as the chromatography-optimization index. The regression model was established by orthogonal regression design. The chromatography-optimization index was filtered by the intelligent filter program, and the optimization of the separation conditions was obtained. The experimental results showed that the average relative deviation between the experimental values and the predicted values was 0. 18% at the optimum and the optimization results were satisfactory.


Luo C.,Chongqing Environmental Monitoring Center | Guo Z.,Chongqing Environmental Monitoring Center | Sun J.,Chongqing Environmental Monitoring Center
Chinese Journal of Chromatography (Se Pu) | Year: 2010

A method for the determination of seventeen phthalate esters in sediment by accelerated solvent extraction CASE/, gel-permeation chromatography (GPC) and gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) has been developed. The target compounds were extracted at 100 °C and 103.4 MPa (l 500 psi) by ASE using the mixtures of dichloromethane and acetone (l: 1, v/v) as solvent. In order to eliminate the interferences from larger molecular sizes, the extract was purified at a flow rate of 5. 0 mL/min by GPC. Following that, the extract was concentrated to a final volume of 1 mL exactly. The GC-MS/MS was applied to quantitative and qualitative analysis. Internal standard calibration approach was adopted, and the detection limits of seventeen phthalate esters ranging from 0. 05 to 0. 40 μg/kg were obtained. The correlation coefficients were beyond 0. 996, the recoveries were from 50. 5% to 107. 9%, and the relative standard deviations were from 3. 5% to 13. 9%. Besides; the surrogate compounds spiked were used to monitor the performance of the method; and the recoveries were from 65. 3% to 95. 8% for the three surrogate compounds. The method is fast; sensitive and exact for analyzing seventeen phthalate esters simultaneously.


PubMed | Chongqing Environmental Monitoring Center and Chongqing Academy of Environmental Science
Type: Journal Article | Journal: Environmental science and pollution research international | Year: 2015

To assess the heavy metal pollution in Changshou Lake, sediments were collected from nine sites at three periods (dry, normal, and wet) in 2013. The Hg, As, Cr, Cd, Pb, Cu, and Zn levels were then determined. The index of geoaccumulation (I geo) and the sediment pollution index (SPI) were applied to the sediment assessment, and Pearsons correlation analysis and factor analysis (FA) were performed to identify common pollution sources in the basin. The results showed that heavy metals presented significant spatial variations with Cr, Cd, Pb, Cu, Zn, Hg, and As concentrations of 29.66~42.58, 0.62~0.91, 24.91~37.96, 21.18~74.91, 41.65~86.86, 0.079~0.152, and 20.17~36.88 mg kg(-1), respectively, and no obvious variations were found among the different periods. The average contents of the metals followed the order Zn>Cu>Cr>Pb>As>Cd>Hg, which showed a high pollution in the sediments collected from open water and at the river mouth. The assessment results indicated that toxic heavy metals presented obvious pollution with I Hg of 0.64~1.36 (moderately polluted), I Cd of 1.66~2.22 (moderately to heavily polluted), and I As of 1.21~2.07 (moderately to heavily polluted). The heavy metal pollution states followed the order Cd>As>Hg>Cu>Pb>Zn>Cr, and the SPI showed that the sediment collected from open water area was more polluted than those obtained from the tributaries and the river mouth. Cr, Cd, Hg, Pb, Cu, As, and Zn were mainly attributed to sediment weathering with Hg, Pb, and Cu and partially due to domestic sewage from the upper reaches. These results indicate that the more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution.

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