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Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing

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Frontiers of environmental Science & Engineering 2007年第2期1卷 159-165页

作者： ZHAO Peng ZHU Tong LIANG Baosheng HU Min KANG Ling GONG Jicheng State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental SciencesPeking UniversityBeijing 100871China

Agricultural activity is one of the most important sources of aerosol *** understand the mass distribu-tion and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing,particle samples were collected using a microorifice uniform deposit impactor(MOUDI)in the summer of 2004 in a suburb vege-table *** distribution of the particles and their inor-ganic water-soluble ions in the diameter range of 0.18-18 mm were *** dominant fine particle ions were SO_(4)^(2−),NO^(3−),and NH_(4)^(+).The association of day-to-day variation of the concentration of these ions with temperature,humidity,and solar radiation suggested that they are formed by the reac-tion of NH_(3) released from the vegetable field with the acid species produced from photochemical *** particle K+is likely from vegetation emission and biomass *** particles like Ca^(2+),Mg^(2+),NO_(3)^(−),and SO_(4)^(2−)are sug-gested to come from the mechanical process by which the soil particle entered the atmosphere,and from the reaction of the acid species at the surface of the soil *** results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields,and vegetable fields in suburban Beijing contribute significantly to the aerosol particle.

关键词： mass size distribution coarse particle fine particle source

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Effects of road networks on ecosystem service value in the Longitudinal Range-Gorge Region

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Chinese Science Bulletin 2007年第A02期52卷 180-191页

作者： WANG Juan CUI BaoShan LIU ShiLiang DONG ShiKui WEI GuoLiang LIU Jie Sate Key Joint Laboratory of Environmental Simulation Pollution Control School of Environment Beijing Normal University Beijing 100875 China China Non-ferrous Metals Resource Geological Survey Beijing 100021 China

基于陆地使用(陆)(在 1985 和 2000 )并且在纵的范围峡区域( LRGR )的道路网络( RN )数据，在道路网络的骚乱下面的生态系统服务值( ESV )损失被使用风景降级索引( LDI )在生态系统服务功能( ESF )上澄清人的活动的效果估计。结果证明 E... 详细信息

基于陆地使用(陆)(在 1985 和 2000 )并且在纵的范围峡区域( LRGR )的道路网络( RN )数据，在道路网络的骚乱下面的生态系统服务值( ESV )损失被使用风景降级索引( LDI )在生态系统服务功能( ESF )上澄清人的活动的效果估计。结果证明 ESV 减少了超过

关键词：生态环境道路网络系统纵向岭谷区

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simulation and control strategy for the variational influent of WWTP

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Journal of environmental Sciences 2006年第1期18卷 62-68页

作者： LIU Yan-chen FAN Long SHI Han-chang WANG Zhi-qiang State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science and Engineering TsinghuaUniversity Beijing 100084 China

With the development of activated sludge model, the simulation software for the design and operation of wastewater treatment plant （WWTP） was produced and has been widely used. The dynamic change of the quality and flow of influent are major factors causing the unstable operation of wastewater treatment process. As a basic model, ASMI model was used for the simulation of activated sludge process, and double exponential model was selected for the simulation of secondary sedimentation tank. The influences of influent change to the aeration tank and secondary sedimentation tank were investigated, and the relationship among influent change, the quality of effluent and the level of sludge blanket in secondary sedimentation tank was established. On the basis of the simulation results, the operation of the WWTP could be adjusted under the dynamic change of the influent. Furthermore, the controlling strategy combined the feed-forward on the influent flow and the feedback on the level of sludge blanket in the secondary sedimentation tank was studied.

关键词： modeling dynamic simulation static simulation controlling strategy influent

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Decolorization of reactive brilliant red K-2BP by white rot fungus under sterile and non-sterile conditions

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Journal of environmental Sciences 2006年第3期18卷 428-432页

作者： GAO Da-wen WEN Xiang-hua QIAN Yi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environment Science and Engineering TsinghuaUniversity Beijing 100084 China.

Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is treated under sterile conditions. A feasible study was made for using white rot fungus Phanerochaete chrysosporium to degrade reactive brilliant red K-2BP dye under non-sterile conditions. The results showed that there was no decolorizing effect under non-sterile condition if white rot fungus was incubated under non-sterile condition, and the decolorization was always near to 0% during decolorizing test for 3 d; in the meantime, a lot of yeast funguses were found in liquid medium when white rot fungus was incubated under non-sterile conditions; however, if white rot fungus was incubated under sterile condition firstly, its decolorization was above 90% under non-sterile condition, which was similar to that of sterile condition. So we point out that the treating process for wastewater with dyes should be divided into two stages. The first stage is that white rot fungus should be incubated under sterile conditions, and the second stage is that reactive brilliant red K-2BP is decolorized under non-sterile conditions. The method not only save the operation cost which decolorizing reactive brilliant red K-2BP under sterile condition, but also provide the feasibility for using white rot fungus to degrade wastewater with dyes under non-sterile conditions.

关键词： white rot fungus Phanerochaete chrysosporium reactive brilliant red K-2BP decolorization non-sterile condition

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Heterogeneous reaction of NO_(2) on the surface of NaCl particles

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Science China Chemistry 2006年第4期49卷 371-378页

作者： LI Hongjun ZHU Tong DING Jie CHEN Qi XU Bingye State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental SciencePeking UniversityBeijing 100871China

The heterogeneous reaction of NO_(2)on NaCl particles has been investigated with the new sample preparation and the mode of gas-solid free *** Reflectance Infrared Fourier Transform Spectroscopy(DRIFTS)is used to characterize the adsorbed products in situ,combined with Ion Chromatographic(IC),X-ray Photoelectron Spectroscopy(XPS)and Scan Electron Micros-copy(SEM).Our results indicate that the reaction is not limited to the surface of the NaCl particles,but penetrated into the upper *** reactive sites determine the *** measurements show that nitrate formation on sodium chloride is second order in NO_(2)concentration and reactive uptake coefficient is(1.54±0.70)×10^(-5).

关键词： DRIFTS gas-solid diffusion heterogeneous reaction reaction order reactiveuptake coefficient

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Characteristics of wetland functional degradation and its ecological water requirement for restoration in Yilong Lake of Yunnan Plateau

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Chinese Science Bulletin 2006年第B11期51卷 127-135页

作者： CUI Baoshan ZHAI Hongjuan State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

The wetland functional degradation can be described as the weakening orunbalance of the wetland functions under natural interference or active jamming, which makes thewetland unable to perform its unique functions or causes the weakening of these functions. By usingfuzzing mathematics, this paper studied the grades the wetland functions and calculated their indexvalues. By this quantitative method and based on the function index values, we analyzed the wetlandfunction degradation and calculated the water quantity required to meet different functional needsin each season... Here we put forth three graded restoration schemes by integrating the ecologicalwater requirement of different grades with the ecological restoration including water replenishing,water consumption and water pollution. According to the calculated model, the water level and waterquantity for the low scheme are 1414.53 m and 1.30X10~8 m~3 respectively; 1415.38 m and 1.78X10~8m~3for the middle sheme, and 416.87 m and 2.14X10~8 m~3 for the high scheme.

关键词：泛函降解泛函索引生态水用水需求水文学

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Experimental Study on Aero Conductivity of Porous Media

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Journal of China University of Geosciences 2006年第4期17卷 332-336页

作者：陈家军杨官光刘运武郑冰杨建 State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Hegang Meteorological Bureau Hegang 154100 China

To study the variation pattern of aero conductivity of different porous media under low pressure conditions, three kinds of media are selected. These include sandy clay loam, fine sand, and medium sand, and air us fluid to conduct soil column ventilation tests. Pressure at both ends of the colruns is measured under different ventilation flow rates during testing. The test results show that the aero conductivity, solved by Darcy＇s law, is not a coustant. It is a variable, which increases first when air flow velocity is less than 0. 258 7 cm/s for sandy clay loam, 0. 637 3 cm/s for fine sand and then decreases when air flow velocity is bigger than that with the increase of the ventilation flow rate when the medium is determined. By analyzing various factors that influence the flow resistance, the reasons for variation in aero conductivity are found us follows： first, the change of pore structure results in better ventilation; second, the relatiouship hetwcen pressure head loss and air flow velocity is nonlinear, and it is beyond the condition of the Iminar flow domain to which Darcy＇ s law can he applied, when the air flow rate increases to a certain value and the flow velocity is in the transition range to turbulent flow.

关键词： aero conductivity Darcy＇ s law pressure head loss nonlinear.

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pollution characteristics of atmospheric fine particles and their secondary components in the atmosphere of shenzhen in summer and in winter

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Science China Chemistry 2006年第5期49卷 466-474页

作者： NIU Yuwen1,2,HE Lingyan1,2,HU Min2,ZHANG Jing2 & ZHAO Yunliang2 1. shenzhen Graduate School of Peking University,shenzhen 518055,China 2. State Joint key laboratory of environmental simulation and pollution control,College of environmental Sciences,Peking University,Beijing 100871,China 1. Shenzhen Graduate School of Peking University Shenzhen 518055 China 2. State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China

Two field measurements for atmospheric fine particles were conducted in Baoan district of shenzhen during the summer and winter in 2004. Totally 30 sets of 24 h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal varia- tions and secondary pollution characteristics of fine particles during the sampling periods were dis-cussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m-3 and 57 μg·m-3, respectively, and those in winter were 99 μg·m-3 and 135 μg·m-3, respec-tively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol compo-nents in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South China Sea in summer, and the air quality was good. The prevailing wind in winter was from China's Mainland to the north, and the polluted air mass led to poor air quality.

关键词： PM2.5, mass concentration, secondary pollution, seasonal variation, shenzhen.

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Effects of Micronutrient Niacin on Treatment Efficiency of Textile Wastewater

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 737-741页

作者： LIANG Wei HU Hongying GU Xin CHE Yuling WANG Hui GUO Yufeng SONG Yudong State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 Hubei China Environment Simulation and Pollution Control State Key Joint Laboratory Department of Environmental Science and EngineeringTsinghua University Beijing 100084 China

Textile wastewater is well known as one of the wastewaters to be most difficultly treated. The effects of niacin on textile wastewater treatment efficiency were studied by continuous addition of 1.0 mg·L^-1 niacin, the physical and chemical indexes of the water samples, such as COD, ammonia and dehydrogenase activities, were analyzed every day with standard methods, and obvious improvement in wastewater treatment performance was achieved. The exact results showed that：① Niacin could improve the COD removal efficiency signifcantly with removal rates being 1.31 times as to those of the control system; ② under this experimental condition, addition of niacin had almost no effect on the removal of ammonia;③ Addition of niacin could improve the activity of dehydrogenase by 130 %. It proved that the biological treatment performance of textile wastewater treatment system probably could be optimized through micronutrient niacin supplement.

关键词： textile wastewater biological treatment niacin, COD dehydrogenase activities

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pH effect on stabilization/solidification of industrial heavy metal sludge

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Chinese Journal Of Geochemistry 2006年第B8期25卷 86-87页

作者： Huili LIU Kaixuan ZOU Yinian ZHU Department of Resources and Environmental Engineering Guilin University of Technology Guilin 541004 China State Key Laboratory of Pollution Control andResources Reuse School of the Environment Nanjing University Nanjing 210093 China Industrial Waste Treatment Station of Baoan District Shenzhen City Shenzhen 518101 China

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