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COMPOSITE MODELING APPROACH AND EXPERIMENTAL STUDY FOR SUBSURFACE TRANSPORT OF CONTAMINANTS FROM LAND-DISPOSAL SITES

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Journal of Hydrodynamics 2003年第4期15卷 1-9页

作者： Wang Chao, Wang Pei-fang, Li Yong department of environmental {2., Hohai {3., nanjing 2.0098, China Dept. of Environ. Eng. Hohai Univ. Nanjing 210098 China

A composite modeling approach was presented for simulating thethree-dimensional (3.D) subsurface transport of dissolved contaminants with transformation *** approach was based on vertical infiltration and contaminant transport in the unsaturated zoneand 3.D groundwater flow and contaminant migration in the saturated zone. Moisture movement andgroundwater flow were considered to be steady, but contaminant transport was treated as continuousand transient. The transformed unsaturated zone and saturated zone transport equations were solvednumerically with different techniques. The model contains a 3.D solution to flow and transport inthe saturated zone, as well as two-dimensional solutions to vertical cross-sectional and arealscenarios. In order to verify the composite modeling, extensive experiments were conducted in twolarge-scale variable-slope soil tanks of 12.0cm in length, 150cm in width and 150cm in height. Sandsoil was filled in the tank as the porous media. The solutions of KBr or NH_4C1 were introduced intoeach soil tank from 80 X 3.cm^2.area sources located on the top of the porous medium. Results fromnumerical simulations were compared with the data from tests. Predicted results are in goodagreement with the experimental data.

关键词： composite modeling groundater flow finite element model experiment

Two Novel Compact High-Isolation Polarization-Independent Four-Port Optical Circulators

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光通信技术 1998年第2期 160-165页

作者： Xu Rongkai Xu Peiying(department of Electronic science & {2.,{3. university,{3. 2.0093)

Two new designed compact high-isolation polarization-independent opticalcirculator have been conceived. The four-port circulators have been designed for 1. 3.msingle-mode fiber systems. Their composition are very simple. Theoretical calculationsindicate the second one has the insertion loss and isolation are≤1. 2.B and ≥50dB respectively.

关键词： Optical circulator Isolation Extinction ratio

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, {3. 2.0044, China b College of environmental science and engineering, Hohai university, {3. 2.0098, China College of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 China College of environmental science and {2. 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

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 {2., nanjing 2.0097, China 2.State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment,{3., nanjing 2.0093, China 3.Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of environmental science and engineering, Tongji {2., Shanghai 2.0092. 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

Study on the simulation of transparency of Lake Taihu under different hydrodynamic conditions

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science China Earth sciences 2006年第z1期49卷 162-175页

作者： PANG Yong, LI Yiping & LUO Liancong College of environmental science and {2., Hohai {3., nanjing 2.0098, China nanjing Institute of Geography & Limnology, Chinese Academy of sciences, nanjing 2.0098, China Hohai Univ Coll Environm Sci & Engn Nanjing 210098 Peoples R China Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210098 Peoples R China

It was indicated in this study that there were negative relations between the concentrations of suspended solid (SS) and transparency according to the analysis of measured data of Lake Taihu. Their relations in pervious studies were reviewed, which showed that the changes of transparency in Lake Taihu could be reflected by simulating suspended solid concentration (SSC). Measured data showed that the changes of SSC with wind speed were similar at different water *** increased with the increasing of wind speed. Both wave and lake current of Lake Taihu had positive relations with SSC. However, wave was the main factor affecting sediment suspension, while flow took the second place. In this study, a numerical model coupling lake current, wave and SSC of Lake Taihu was developed. In the SS model, the combined effects of wave and current were *** amounts of suspended and deposited sediments near the lake bed surface layer were treated separately. The stochastic characteristics of turbulent flow pulsation near lake beds were also considered, and the start-up conditions of sediment suspension were introduced to the model. The model elucidated the mutual exchange processes between sediment particles in SS and active sediments within and on the bed surface layer. Simulated results showed that lake current had relatively significant effects on the SSC at littoral areas of Lake Taihu, while SSC at the central area of the lake was mainly influenced by wave. The changes of transparency with SSC were simulated for Lake Taihu using this model. Calculated results were validated by measured data with good fitness, which indicated that the model is basically suitable for the simulation and prediction of transparency of Lake Taihu.

关键词： transparency suspended solid hydrodynamlc sediment suspension model.

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern China

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science China Earth sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2.1. Cold and Arid Regions environmental and engineering Research Institute, Chinese Academy of {2.s, Lanzhou 73.000, China 2. College of Geography, {3. Normal university, {3. 2.0097, China 1. Cold and Arid Regions environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. College of Geography Nanjing Normal University Nanjing 210097 China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2.01. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan university of Technology(Materials science) 2009年第2期24卷 326-329页

作者：郭伟 department of Material engineering Yancheng Institute of Technology Institute of Material science and engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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science China Chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2.ZHONG QingDong2.& LU TianHong3.1department of Chemical {2.,Shanghai Institute of Technology,Shanghai 2.02.0},China 2.chool of Materials {2. and {2.,Shanghai university,Shanghai 2.0072.China 3.0} of Chemistry,nanjing Normal university,nanjing 2.0097,China 1. department of Chemical engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPS that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.73. × 10-12.mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

Web Application Comprehension Based on Dependence Analysis

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Wuhan university Journal of Natural sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2., XU Bao-wen 1 , JIANG Ji-xiang 1 1.department of Computer science and {2., Southeast {3., nanjing 2.0096, Jiangsu, China 2.College of Computer science and {2., nanjing university of Technology, nanjing 2.0009, Jiangsu , China Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***) Najing university of Technology College of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.41156.37) (ISNI:***) Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 3.1 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (603.3.66, 603.3.2.). National Grand Fundamental Research 973.Program of China (2.02.B3.2.00) and National Research Foundation for the Doctoral Program of Higher Education of ChinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing