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Schleicher N.J.,Karlsruhe Institute of Technology | Schafer J.,CNRS Laboratory of Oceanic Environments and Paleo-environments (EPOC) | Chen Y.,Karlsruhe Institute of Technology | Blanc G.,CNRS Laboratory of Oceanic Environments and Paleo-environments (EPOC) | And 5 more authors.
Atmospheric Environment | Year: 2016

Atmospheric particulate mercury (HgP) was studied before, during, and after the Olympic Summer Games in Beijing, China, in August 2008 in order to investigate the efficiency of the emission control measures implemented by the Chinese Government. These source control measures comprised traffic reductions, increase in public transportation, planting of vegetation, establishment of parks, building freeze at construction sites, cleaner production techniques for industries and industry closures in Beijing and also in the surrounding areas. Strictest measures including the "odd-even ban" to halve the vehicle volume were enforced from the 20th of July to the 20th of September 2008. The Olympic period provided the unique opportunity to investigate the efficiency of these comprehensive actions implemented in order to reduce air pollution on a large scale. Therefore, the sampling period covered summer (August, September) and winter (December and January) samples over several years from December 2005 to September 2013. Average HgP concentrations in total suspended particulates (TSP) sampled in August 2008 were 81 ± 39 pg/m3 while TSP mass concentrations were 93 ± 49 μg/m3. This equals a reduction by about 63% for TSP mass and 65% for HgP, respectively, compared to the previous two years demonstrating the short-term success of the measures. However, after the Olympic Games, HgP concentrations increased again to pre-Olympic levels in August 2009 while values in August 2010 decreased again by 30%. Moreover, winter samples, which were 2- to 11-fold higher than corresponding August values, showed decreasing concentrations over the years indicating a long-term improvement of HgP pollution in Beijing. However, regarding adverse health effects, comparisons with soil guideline values and studies from other cities highlighted that HgP concentrations in TSP remained high in Beijing despite respective control measures. Consequently, future mitigation measures need to be tailored more specifically to further reduce HgP concentrations in Beijing. © 2015 Elsevier Ltd.


Yang Y.,Tsinghua University | Shao X.,Tsinghua University | Zhou G.,China Research Academy of Environmental science | Qin C.,Tsinghua University
Qinghua Daxue Xuebao/Journal of Tsinghua University | Year: 2015

30 surface water environmental quality models in the literatures were analyzed to classify model indicators according to the research topic, assessment criteria, and operation grade. Some features of these models such as model development, functional diversity, methodological diversity and application were used to develop an assessment system for hydrodynamic models while the classification variable was the research topic. An application of the ELCIRC model showed that the ELCIRC model does well. ©, 2015, Press of Tsinghua University. All right reserved.


An J.,CAS Institute of Atmospheric Physics | Xiang W.,CAS Institute of Atmospheric Physics | Han Z.,Chinese Academy of Sciences | Xiao K.,Tsinghua University | And 7 more authors.
Atmospheric Environment | Year: 2013

The urban canopy layer parameterization (UCP), a successive bias correction method (SBC), an atmospheric dispersion module for denser-than-air releases, and the emission intensity of chemicals monitored by a Fourier-transform-infrared remote sensor (EM27) were incorporated into the Institute of Atmospheric Physics emergency response model (IAPERM). IAPERM's performance was tested in Beijing using the field data collected from a 325-m meteorological tower and sulfur hexafluoride (SF6) diffusion and pool fire experiments. The results show that the IAPERM simulations of the vertical wind speeds in the urban canopy layer (UCL) with the UCP perform much better than those with the Monin-Obukhov similarity parameterization scheme. The IAPERM forecasts for air temperature and relative humidity are more accurate than those for wind speed and direction, which require correction. When the SBC with the local terrain effect is adopted, the wind speed and direction and the maximum concentrations of black carbon near the ground are well forecasted. IAPERM reproduces the spatial distributions of the SF6 observations more accurately near the release source (≤500m) than at locations far away from the release source with the use of the observed meteorological parameters. These results suggest that IAPERM could be a promising tool for passive and dense gas diffusion simulations or forecasts. © 2013 Elsevier Ltd.


Wei C.-Y.,Petrochina | Wang H.-T.,Petrochina | Zhao L.-N.,China Research Academy of Environmental science | Zhang S.-C.,Petrochina | Cheng L.,Petrochina
Bulletin of Mineralogy Petrology and Geochemistry | Year: 2012

Two groups of chloroform bitumen "A" samples were separated from some selected sedimentary rock samples using an accelerated solvent extraction apparatus (ASE300) and a fast Soxhlet extraction apparatus, respectively. The geochemical parameters of saturated hydrocarbons, aromatics, resin and asphaltene from the different chloroform bitumen "A" sample groups were systematically studied and compared. The experiment results showed that the obtained amounts of chloroform bitumen "A" are slightly higher using the ASE300 than using the fast Soxhlet in most cases, and that the main increments of using ASE300 are resin and asphaltene. GC-MS study indicated that saturated and aromatic hydrocarbons extracted from two groups of chloroform bitumen "A" samples are highly consistent, the deviations of the quantitative results are less than 5%, the differences of measured carbon stable isotope compositions for any identical component obtained respectively from two extraction methods fall into the range of ± 0.5‰. These results indicated that ASE300 and fast Soxhlet extracted instruments are comparative. Therefore, the ASE300, the relatively consumption saving and analytically efficient method, can replace the fast Soxhlet extraction apparatus in geochemical pretreatment experiments.


Huo T.,Agricultural University of Hebei | Bai S.,China Research Academy of Environmental science | Bai S.,Agricultural University of Hebei
Advanced Materials Research | Year: 2012

Through large-scale model tests on composite foundation of cement-soil piles under cyclic loading, a program was compiled based on the platform of MATLAB 7.0, considering the effects of cement mixing ratio, replacement ratio, cyclic stress ratio and number of cyclic on the permanent settlement of composite ground. A back-propagation neural network model to predict the settlement was established, and its prediction accuracy was inspected. Meanwhile, an predicting model of multivariable linear regression analysis was established .To compare the prediction accuracy of the two methods, and the result shows that the trained neural network have the better predictive and generalization. © (2012) Trans Tech Publications, Switzerland.


Liu M.,Tongji University | Liu M.,China Research Academy of Environmental Science | Zhao Y.,China Research Academy of Environmental Science | Xi B.,China Research Academy of Environmental Science | Hou L.-A.,Tongji University
Desalination and Water Treatment | Year: 2015

A hybrid granular bed-contact oxidation biofilm baffled reactor (GBCOBBR) was studied with molasses wastewater for combined carbon and nitrogen removal. The GBCOBBR was operated at various organic loading rates ranged from 1.5 to 7 kg chemical oxygen demand (COD) m−3d−1 and ammonia nitrogen loading rates ranged from 0.05 to 0.204 kg (Formula presented.)  m−3d−1. Carbonaceous matter and nitrogen were removed simultaneously in the GBCOBBR at different recycle to influent ratios ranged from 1.5 to 2.5. The results demonstrated that when the loading rates of COD and ammonia were 3 kg COD m−3d−1 and 0.085 kg (Formula presented.)  m−3d−1, COD removal efficiencies of 90.2–91.5% were observed in the anaerobic unit, and over 92% by the two-stage treatment configuration (anaerobic and aerobic units) at all recycle to influent ratios. At all the recycle to influent ratios studied, almost all ammonia was converted to nitrate nitrogen with only small traces of nitrite nitrogen in the nitrification unit and total nitrogen removal efficiencies of 80.5–82% were observed. © 2014, © 2014 Balaban Desalination Publications. All rights reserved.


Liu M.,Tongji University | Hou L.-A.,Tongji University | Xi B.,China Research Academy of Environmental Science | Zhao Y.,China Research Academy of Environmental Science | Xia X.,China Research Academy of Environmental Science
Applied Surface Science | Year: 2013

A novel hybrid mesoporous aluminosilicate sieve (HMAS) was prepared with fly ash and impregnated with zeolite A precursors. This improved the mercury adsorption of HMAS compared to original MCM-41. The HMAS was characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, Fourier transform infrared (FTIR) analysis, transmission electron microscopy (TEM) images and 29Si and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra. These showed that the HMAS structure was still retained after impregnated with zeolite A. But the surface area and pore diameter of HMAS decreased due to pore blockage. Adsorption of mercury from aqueous solution was studied on untreated MCM-41and HMAS. The mercury adsorption rate of HMAS was higher than that of origin MCM-41. The adsorption of mercury was investigated on HMAS regarding the pH of mercury solution, initial mercury concentration, and the reaction temperature. The experimental data fit well to Langmuir and Freundlich isotherm models. The Dublin-Radushkevich isotherm and the characterization show that the mercury adsorption on HMAS involved the ion-exchange mechanisms. In addition, the thermodynamic parameters suggest that the adsorption process was endothermic in nature. The adsorption of mercury on HMAS followed the first order kinetics. Crown Copyright © 2013 Published by Elsevier B.V. All rights reserved.


Chen Z.,China Aerospace Science and Technology Corporation | Xue H.,China Research Academy of Environmental Science
2010 2nd Conference on Environmental Science and Information Application Technology, ESIAT 2010 | Year: 2010

After several years of implementation, the EIA system in China has developed into a framework that is suitable for its unique conditions. However, since there are some problems in China's EIA system, the aims of this paper are to evaluate both the strength and weakness of practice and provide suggestions for its improvement. ©2010 IEEE.


Liu M.,Tongji University | Hou L.-A.,Tongji University | Yu S.,Tongji University | Xi B.,China Research Academy of Environmental Science | And 2 more authors.
Chemical Engineering Journal | Year: 2013

In this paper, the MCM-41 has been modified by impregnation with zeolite A to prepare a kind of new adsorbent. The adsorption of TC from aqueous solutions onto modified MCM-41 has been studied. It was discovered that the adsorption capability of zeolite A modified MCM-41 (A-MCM-41) increased dramatically after modification. The modified MCM-41 was characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, Fourier Transform Infrared (FTIR) analysis, Transmission electron microscopy (TEM) images, and 29Si and 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) spectra. The modified MCM-41 structure was still retained after impregnated with zeolite A but the surface area and pore diameter decreased due to pore blockage. The adsorption of TC on modified MCM-41 was discussed regarding various parameters such as pH, initial TC concentration, and the reaction time. The pH effects on TC adsorption indicated that the adsorbents had better adsorption performances in acidic and neutral conditions. The adsorption isotherms were fitted well by the Langmuir model. The adsorption kinetics was well described by both pseudo-second order equation and the intra-particle diffusion model. The adsorption behavior in a fixed-bed column system followed Thomas model. The adsorption behavior of TC was the chemical adsorption with an ion exchange process and electrostatic adsorption. © 2013 Elsevier B.V.


PubMed | China Research Academy of Environmental Science and Tongji University
Type: Journal Article | Journal: Chemical engineering journal (Lausanne, Switzerland : 1996) | Year: 2014

In this paper, the MCM-41 has been modified by impregnation with zeolite A to prepare a kind of new adsorbent. The adsorption of TC from aqueous solutions onto modified MCM-41 has been studied. It was discovered that the adsorption capability of zeolite A modified MCM-41 (A-MCM-41) increased dramatically after modification. The modified MCM-41 was characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, Fourier Transform Infrared (FTIR) analysis, Transmission electron microscopy (TEM) images, and

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