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Equations and their physical interpretation in numerical modeling of heavy metals in fluvial rivers

中国科学：技术科学英文版 2010年第2期53卷 548-557页

作者： HUANG SuiLiang Numerical Simulation Group for Water Environment, Tianjin Key Laboratory of environmental Remediation and Pollution Control, Key Laboratory of Pollution Processes and environmental Criteria of the Ministry of Education college of environmental science and Engineering, Nankai university, Tianjin 300071, china 1. Numerical Simulation Group for Water Environment Tianjin Key Laboratory of Environmental Remediation and Pollution Control Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education college of environmental science and Engineering Nankai University Tianjin 300071 China

Based on the previous work on the transport-transformation of heavy metal pollutants in fluvial rivers, this paper presented the formulation of a two-dimensional model to describe heavy metal transport-transformation in fluvial rivers by considering basic principles of environmental chemistry, hydraulics, mechanics of sediment transport and recent developments along with three very simplified test cases. The model consists of water flow governing equations, sediment transport governing equations, transport-transformation equation of heavy metal pollutants, and convection-diffusion equations of adsorption-desorption kinetics of particulate heavy metal concentrations on suspended load, bed load and bed sediment. The heavy metal transport-transformation equation is basically a mass balance equation, which demonstrates how sediment transport affects transport-transformation of heavy metals in fluvial rivers. The convection-diffusion equations of adsorption-desorption kinetics of heavy metals, being an extension of batch reactor experimental results and a major advancement of the previous work, take both physical transport, i.e. convection and diffusion and chemical reactions, i.e. adsorption-desorption into account. Effects of sediment transport on heavy metal transport-transformation were clarified through three examples. Specifically, the transport-transformation of heavy metals in a steady, uniform and equilibrium sediment-laden flow was calculated by applying this model, and results were shown to be rational. Both theoretical analysis and numerical simulation indicated that the transport-transformation of heavy metals in sediment-laden flows with clay-enriched riverbed possesses not only the generality of common tracer pollutants, but also characteristics of transport-transformation induced by sediment motion. Future work will be conducted to present validation/application of the model with available data.

关键词： heavy metals transport-transformation water-sediment-pollutants interaction fluvial rivers numerical modeling

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Research on Indicator System of Regional Eco-efficiency:A Case Study of Chengyang District

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Chinese Journal of Population,resources and Environment 2006年第4期4卷 54-58页

作者： Zhou Zhenfeng1,2,Sun Lei2,Sun Yinglan2 1.college of resources&Environment,Laiyang Agricultural college,Qingdao,Shandong 266109,china 2.School of environmental science and Engineering,Ocean university of china,Qingdao,Shandong 266003,china college of resources & Environment Laiyang Agricultural College Qingdao Shandong 266109 China School of environmental science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China

Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production *** the popularity of the term"eco-efficiency"in business,limited attention has been paid to measuring and reporting regional eco-efficiency for local government policy *** on the concept and method of eco-efficiency,an indicator system of regional eco-efficiency is established in this *** indicator system comprises 22 indicators,which are divided in to three categories including socio-economic development,resources consumption, environmental *** a promising statistical technique, principle component analysis is used to set the weight of indicators which attempts to calculate the eco-efficiency indices of Qingdao's Chengyang *** results show that the eco-efficiency of Chengyang District has clearly improved 35.1% with small fluctuation from 1995 to ***-economic development index and resources consumption index also represent obvious increasing *** correlation coefficient between soci-economic development index and resources consumption index is 0.979,which means the social progress and economic growth of Chengyang District depend on an extravagant consumption of *** environmental pressure index increased slowly before 1997 and declined gradually after 1997,due to more attention being paid to environmental protection by local government in recent *** District still keeps the traditional economic development mode with a high consumption and high production,so the emphases of future development should put on improving the improving the efficient use of natural resources and promoting environmental management *** results show that the indicators system of regional eco-efficiency is a promising method to quantitatively evaluate resources and environmental efficiency and provide an effective decision-making support for local governments.

关键词： regional eco-efficiency indicator system Ecoefficiency Synthetic Index (ESI) Principle Component Analysis (PCA)

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Dark respiration in the light and in darkness of three marine macroalgal species grown under ambient and elevated CO_2 concentrations

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Acta Oceanologica Sinica 2011年第1期30卷 106-112页

作者： ZOU Dinghui GAO Kunshan XIA Jianrong college of environmental science and Engineering South China University of Technology Guangzhou 510006 China The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of Education Guangzhou 510006 China State Key Laboratory of Marine environmental science Xiamen University Xiamen 361005 China college of environmental science and Engineering Guangzhou University Guangzhou 510006 China

Dark respiration （non-photorespiratory mitochondrial respiration）, which occurs both in the light and in darkness, is vital for growth and survival of algae and plays a critical role in modulating the carbon balance of them. In the present study, we have investigated dark respiration in the light （RL） and in darkness （RD） in three marine macroalgal species, Hizikia fusiformis （phaeophyta）, Gracilaria lemaneiformis （Rhodophyta） and Ulva lactuca （Chlorophyta）, cultured at 20 ℃ using aeration with two CO2 conditions： current ambient （CO2 concentration about 380 μl/L） and elevated CO2 （approximately 720 μl/L） air. RL was estimated by using the Kok method, whereas RD was determined as the rate of O2 influx at zero light. The results showed that both RL and RD were unchanged for the elevated CO2-grown algae relative to ambient CO2 concentration for all the algal species tested. However, RL was significantly lower than RD across all the algal species and growth CO2 treatments, demonstrating that daytime respiration was partly depressed by the light. The percentage of inhibition of respiration by light was similar between ambient and elevated CO2- grown algae. The ratio of respiration to photosynthesis, which tended to decrease when estimated using RL instead of RD, was not altered for the elevated relative to ambient CO2 concentration. The results suggest that RL, rather than RD, is a more accurate estimate of nonphotorespiratory carbon loss in marine macroalgae during the daytime. It would not be anticipated that elevated atmospheric CO2 would exert a substantial influence on respiratory flux either in the light or in darkness in these particular marine macroalgal species.

关键词： marine macroalgae respiration CO2 carbon balance

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Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural science:Materials International 2008年第7期18卷 873-878页

作者： Changgen Lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a college of Atmospheric science, Nanjing university of Information science & Technology, Nanjing 210044, china b college of environmental science and Engineering, Hohai university, Nanjing 210098, china college of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 China college of environmental science and Engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： Boundary layer Pressure gradients Impulse Large eddies

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Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2, TAN Zhi-xiang1, 2, DENG Ka-zhong1, 2 1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 221116, china 2. Jiangsu Key Laboratory of resources and environmental Information Engineering, china university of Mining and Technology, Xuzhou 221116, china [a] Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu Key Laboratory of resources and environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2π] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

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New stylophorans(Echinodermata) from the Upper Cambrian of Guangxi,South china

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science china Earth sciences 2008年第2期51卷 181-186页

作者： HAN NaiRen1 & CHEN GuiYing1,2 1 Department of resources and environmental Engineering, Guilin university of Technology, Gulin 54.004. china 2 Faculty of Earth sciences, china university of Geoscience, Wuhan 430074, china Department of resources and environmental Engineering Guilin University of Technology Gulin 541004 China Faculty of Earth sciences China University of Geoscience Wuhan 430074 China

This paper describes for the first time the cornute stylophorans (Echinodermata) in china. The new material came from the Guole Formation of the Furongian (Late Cambrian) in the Guole area of Jingxi, Guangxi Province, South china. These new cornute specimens are preserved in situ and found along with well-preserved trilobites and brachiopods. One new species, Phyllocystis jingxiensis sp. nov., is proposed to accommodate these unusual materials. The new species is defined by the small, heart-shaped theca with the frame composed of ten narrow, smooth and thick marginal plates, three adoral plates and distinctive zygal and aulacophore. Both supracentrals and infracentrals are polygonal-outlined. The marginal plate M1' on the inferior face extends posteriorly to form zygal that possesses a broadened proximal end and the proximal portion joining with the conjunction between M4 and M5 on the inferior face. Aulacophore comprises ten segments at its proximal part and is conical at the middle part (named stylocone). Its distal portion is rather long and bears conspicuous ambulacrum grooves. Tectals are horizontally arranged on superior face and obliquely arranged on inferior face. Both cothurnopore and anal pyramid are vaguely seen on the right anterior corner and the extremity of theca's superior face.

关键词： Phyllocystis Stylophora Echinodermata Cambrian Guangxi South china

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Predicting bioconcentration factor values of organic pollutants based on medv descriptors derived QSARs

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science china Chemistry 2007年第5期50卷 587-592页

作者： CUI ShiHai1,2, YANG Jing1, LIU ShuShen2,3 & WANG LianSheng2 1 college of Chemistry and Environment, Nanjing Normal university, Nanjing 210097, china 2 State Key Laboratory of Pollution Control and resources Reuse, School of the Environment, Nanjing university, Nanjing 210093, china 3 Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, college of environmental science and Engineering, Tongji university, Shanghai 200092, china 1. college of Chemistry and Environment Nanjing Normal University Nanjing 210097 China 2. State Key Laboratory of Pollution Control and resources Reuse School of the Environment Nanjing University Nanjing 210093 China 3. Key Laboratory of Yangtze Aquatic Environment Ministry of Education College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The molecular electronegativity-distance vector (MEDV) is employed todescribe the chemical structure of organic *** linear relationships between themolecular descriptors and BCF values are developed by best subset regression and partial leastsquare regression *** main structural factors influencing the bioactivities are -CH2,-X,-Cnot 2 and q2_(LOO) present good estimation ability and stabilityof *** prediction power for external samples is validated by the model developed from thetraining set.

关键词： POPs, BCF, MEDV, QSAR

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Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, Harbin Normal university, Harbin 150080, china college of resources Environment & Tourism, Capital Normal university, Beijing 100037, china college of Economics and Management, Northeast Agricultural university, Harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China. college of resources Environment & Tourism Capital Normal University Beijing 100037 China. college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

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Research of E-Commerce System Based on EJB for Manufacture Enterprise

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厦门大学学报（自然科学版） 2002年第S1期41卷 286-287页

作者： WEI Zhao-wen 1, LI Yong 2, SU Yi-dan 1 (1. Computer & Information Engineering college, Guangxi university, N anning 530004, china 2. Business Administration college, chongqing university, chongqing 4.004., Chi na)

During the popular and development in Internet, mor e and more EC systems are running on Internet. Manufacture enterprise establishes EC system, integrates the systems between enterprises replace the traditional MI S system. The manufacture enterprise will face some difficulties when it begins to establish EC system. In order to solve the difficulties, the EC system not on ly includes the functions which in general EC system, but also integrates ERP sy stem, manages the enterprise from three aspects: relationship between manufactur er and customers, enterprise resources, and supplying chain, and gives the manuf acturer more intelligent information. As the departments of enterprise exchange data very frequently, connect the sellers and suppliers by using Internet, the t raditional C/S architecture isn’t satisfied by present needs. It is the only wa y that uses Multi-tier architecture. EJB (Enterprise Java Bean) is a Multi-tier distributed architecture designed by SUN company. The Enterprise JavaBeans architecture is a component architecture for the development and development of component-based distributed business app lications. Applications written using the Enterprise JavaBeans architecture are scalable, transactional, and multi-user secure. These applications may be writt en once, and then deployed on any server platform that supports the Enterprise J avaBeans specification. There are many superiorities using EJB when design compu ter system. The EC System for Manufacture Enterprise is based on EJB architecture. We define four EJB containers, namely, CRM component, POM component, Knowledge Management component and ERP component. CRM EJBs take the form of managing the customer- supplier relationship, reducing the number of contracts the manufacturer must ma ke with the end customers. POM EJBs take the form of order processing activities . These order taking, order fulfillment, and managing the logistics and transpor tation involved in the physical movement of the

关键词： E-Commerce EJB CRM ERP

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AN APPROACH TO SEPARATING THE CURRENT VELOCITY IN ESTUARINE AND COASTAL WATERS

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Journal of Hydrodynamics 2009年第4期21卷 512-519页

作者： NI Zhi-hui SONG Zhi-yao WU Li-chun State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Ocean College Hohai University Nanj ing 210098 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210097 China chongqing Education college Chongqing 400067 China

In the near-shore waters, the actual flow is mainly induced by tide, wind and salinity, and the river water runoff should also be included as a component in the estuary waters. The interactions among these major components are very complicated. Many approaches were proposed to study isolated tide and wind-driven currents or run-off based on the measured velocity, with all its components taken as a whole. In this article, firstly, based on the actual hydrodynamic characteristics of estuarine and coastal waters, an approach is proposed to separate the measured velocity by considering the theoretical current velocity profiles and using the least squares method. The vertical structures of tidal, wind-driven currents, density current and runoff can be obtained as well as their proportions in the measured velocity. Then, this approach is applied to the analysis of velocity data obtained in the North Branch of Yangtze River estuary and of laboratory test data. The results are found to be satisfactory. Finally, this approach is used to separate the measured velocity in the South Branch of Yangtze River estuary, to determine not only the bed friction velocity and roughness height, but also the surface wind stress, and to estimate the wind velocity data above the water surface. The results show that this method is simple in principle, practical in use, and reasonable in obtained results. So it can be used to effectively analyze the field data.

关键词： tide wind-driven current density current river water runoff friction velocity roughness height velocity separation

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