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Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of Beijing

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Journal of environmental Sciences 2008年第4期20卷 505-512页

作者： College of environmental Sciences and engineering, Peking University, Beijing 100871, china GUO Huaicheng LIU Yong HUANG Kai WANG Zhen ZHAN Xinye 不详 School of Natural Resources and Environment University of Michigan Ann Arbor 48109 USA department of civil and Resource engineering Dalhousie University Halifax NS B3JIZ1 Canada

This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons （PAHs） in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate （IR） representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction （AF） ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in Beijing, china, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in Beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in Beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 272-309 individual cancer incidences can be attributed to PAHs pollution in the air. The probability of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in Beijing, while the contribution might not be the most significant one.

关键词： polycyclic aromatic hydrocarbons (PAHs) uncertainty analysis human health risk

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AN ANALYSIS OF THE OXYGEN BALANCE IN AN ANOXIC TIDAL RIVER

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Journal of Hydrodynamics 1994年第4期6卷 83-92页

作者： Joseph H. W. Lee, K. W. Choi (department of civil and Structural engineering, University of Hong Kong)Chen Hui-guo Lin Ming-he(environmental Sciences Research Centre, Zhongshan University, Guangzhou 510275, P. R. china) department of civil and Structural engineering University of Hong Kong Hong Kong environmental Sciences Research Centre Zhong.shan University Guangzhou 510275 China

A time-dependent, mixed-segment, slack tide oxygen balance model has been developed for the study of a heavily polluted tidal river discharging to a coastal *** and reaeration, BOD settling, benthal demand, freshwater flushing, and tidal mixing are the key processes modelled. Significant features of the model include the oxygen balance formulation under anoxic conditions and the tidal exchange condition at the seaward boundary. The simple model enables a clear and consistent interpretation of a set of dry season water quality data and an assessment of the assimilative capacity of the river is also made.

关键词： tidal river coastal bay water quality oxygen balance.

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HYDRAULIC RESISTANCE OF SUBMERGED VEGETATION RELATED TO EFFECTIVE HEIGHT

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Journal of Hydrodynamics 2010年第2期22卷 265-273页

作者： WANG Pei-fang WANG Chao ZHU David Z. Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationCollege of Environmental Hohai University Nanjing 210098 China department of civil and environmental engineering University of Alberta Edmonton Canada T6G 2W2

Submerged vegetation has a significant impact on water flow *** investigations include the impact through adding drag resistance and increasing bottom roughness coefficient,which cannot elucidate the characters of real submerged *** evaluate the effects of submerged vegetation on water currents at different velocities,a laboratory experiment was conducted using three kinds of *** effective heights of these vegetations on varying flow velocities were *** equation describing the relationship between the normalized resistance of the submerged plants and the Reynolds number based on the plant effective height was then established and used to calculate the hydraulic resistance parameters of submerged plants in different stages of growth.

关键词： hydraulic resistance submerged vegetation drag force effective height

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Research and Practice of New Rural Community Development Model in Northeast Area

Research and Practice of New Rural Community Development Mod...

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2014年环境污染与大众健康学术会议

作者： Chen LV 1 Jing LV 2 Hong YANG 3 4 1 china University of Geosciences Beijing china 100083 2 jilin institute of Architecture and civil engineering changchun china 130118 3 Harbin institute of Technology Harbin china 150001 4 china Northeast Municipal engineering Design and Research institute changchun china 130021

The change of production mode and increase of farming radius in Northeast Rural recently, led to each area of agricultural cultivation reach to 20 square kilometers become possible. In this paper, make plan ning of Yilong town in Yi’an country of Heilongjiang Province as example, explore the implementation of the new "secondary" level of the town structure. According to the distribution such as farming, transport, pro duction, life, status of infrastructure and other factors, proposed to replace the natural villages in rural com munities, construction of new rural communities with improved social function, complete infrastructure and unique industries. Make rural space system model village organizations with more affordability than the original system of central planning （For short "complex community model"）. Want to take this opportunity to try for the helpful suggestions with construction of new rural villages in the form of sustainable building in Northeast area.

关键词： new rural rural communities complex community model planning preparation

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Spatial distribution of nitrification and denitrification rates of sediment in Wenruitang River, Wenzhou, china

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Acta Geochimica 2006年第S1期 20-21页

作者： Shaoyong LU1,2, Xiangcan JIN2, Jianning GUO2, Qingyun BU2, Feipen YANG3, Xiping CHEN3, Yuye YAO3 1 Research Center of Lake Environment, Chinese Research Academy of environmental Sciences, State environmental Protection Key Laboratory for Lake Pollution Control, Beijing 100012, china 2 department of Environment engineering, jilin architectural and civil engineering institute, changchun 130021, china 3 Headquarters of River Wenruitanghe Regulation Project, Wenzhou, 404042, china

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日本城市污水热能回收利用的发展现状

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吉林建筑工程学院学报 2003年第3期20卷 4-6页

作者：全贞花尹军吉林建筑工程学院环境工程系长春130021

由于热容大,污水及其处理后的水可以成为城区的一个热源,因此,人们非常希望在污水系统规划中回收和再利用这些热能.本文对污水中热能的特征、再利用的规划及日本的实施经验进行了介绍与分析,同时,还介绍了东京市区对热能全面再利用的供... 详细信息

由于热容大,污水及其处理后的水可以成为城区的一个热源,因此,人们非常希望在污水系统规划中回收和再利用这些热能.本文对污水中热能的特征、再利用的规划及日本的实施经验进行了介绍与分析,同时,还介绍了东京市区对热能全面再利用的供热与制冷工程,以及札幌市的融雪工程.

关键词：污水热能利用现状

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生物流化床反硝化工程实例

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吉林建筑工程学院学报 2004年第2期21卷 36-38页

作者：崔玉波吉林建筑工程学院环境工程系长春120021

生物流化床污水处理技术,以其独具的优点受到业内人士的广泛关注和研究.但由于从试验到放大应用存在许多困难,因而实际工程很少.现介绍国外两例将流化床应用于城市污水二级处理出水反硝化的工程实例及其运行中的经验.

关键词：生物流化床反硝化污水处理

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, Beijing 100101, china 2. institute of Forestry, Chinese Academy of Forestry Sciences, Beijing 100091, china 3. department of civil engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, Chinese Academy of Sciences, Beijing 100085, china 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, china Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. department of civil engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Preliminary study on different nutrient pools supplies for the phytoplankton growth in the Jiaozhou Bay in china in the fall of 2004

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Acta Oceanologica Sinica 2007年第3期26卷 110-120页

作者： WANG Dan SUN Jun SONG Shuqun LUAN Qingshan Joey McMurdie Key Laboratory of Marine Ecology ＆ environmental Science Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Depatment of civil ＆ environmental engineering Stanford University California 94305 USA

The source and significance of two nutrients, nitrogen and phosphorous, were investigated by a modified dilution method performed on seawater samples from the Jiaozhou Bay, in autumn 2004. This modified dilution method accounted for the phytoplankton growth rate, microzooplankton grazing mortality rate, the internal and external nutrient pools, as well as nutrient supplied through remineralization by microzooplankton. The results indicated that the phytoplankton net growth rate increased in turn from inside the bay, to outside the bay, to in the Xiaogang Harbor. The phytoplankton maximum growth rates and microzooplankton grazing mortality rates were 1.14 and 0.92 d^-1 outside the bay, 0.42 and 0.32 d^ -1 inside the bay and 0.98 and 0.62 d^-1 in the harbor respectively. Outside the bay, the remineralized nitrogen （Kt = 24.49） had heavy influence on the growth of the phytoplankton. Inside the bay, the remineralized phosphorus（Kt = 3.49） strongly affected the phytoplankton growth. In the harbor, the remineralized phosphorus （Kt = 3.73） was in larger demand by phytoplankton growth. The results demonstrated that the dif- ferent nutrients pools supplied for phytoplankton growth were greatly in accordance with the phytoplankton community structure, microzooplankton grazing mortality rates and environmental conditions. It is revealed that nutrient remineralization is much more important for the phytoplankton growth in the Jiaozhou Bay than previously believed.

关键词： phytoplankton external nutrient internal nutrient remineralized nutrient maximum growth rate microzooplankton grazing mortality rate Jiaozhou Bay

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The Principle of Interaction between Plastic Volumetric and Shear Strains for Unsaturated Soils

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工程科学（英文版） 2007年第3期5卷 51-56页

作者： Wang Jingtao1,2(1.department of architectural engineering,Xinyang Normal University,Xinyang,Henan,464000,china 2.School of civil engineering and Mechanics,Huazhong University of Science and Technology,Wuhan,430074,china)

The principle of interaction between plastic volumetric and shear strains for rock and soil has been extended to the field of unsaturated *** new interactions of suction-plastic volumetric strain and pore air pressure-plastic volumetric strain appear in the unsaturated state of a soil except the interaction between plastic volumetric and shear *** is very important to find that the suction possesses a dual property,which is the origin of generating its special *** the effect of the suction on volumetric strain includes two opposite *** means of this property of suction,the physical significance of effective stress parameter,effects of suction on volume change and preconsolidation pressure,and the mechanism of collapse upon wetting all can be *** addition,it is theoretically proved by application of this principle of interaction that the critical state line for unsaturated soils exists,and is unique and independent of the stress history.

关键词： the principle of interaction between plastic volumetric and shear strains unsaturated soil matric suction the principle of effective stress

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