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Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,nanjing university,nanjing {3.,china 2. nanjing College of Chemical Technology,nanjing 210048,china 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse,nanjing 21003.,china State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing China nanjing College of Chemical Technology Nanjing China Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

3. mathematical model for suspended load transport by turbulent flows and its applications

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science china(Technological sciences) 2004年第2期47卷 237-256页

作者： LU Yongjun1,DOU Guoren1,HAN Longxi2,SHAO Xuejun3.& YANG Xianghua1,3.1.nanjing Hydraulic Research Institute,nanjing 210029,china 2.College of {3. engineering of Hohai university,nanjing 210098,china 3.department of Hydraulic engineering,Tsinghua university,Beijing 100084,china nanjing Hydraulic Research Institute Nanjing 210029 China

This paper presents a 3. mathematical model for suspended load transport in turbulent flows. Based on Dous stochastic theory of turbulent flow, numerical schemes of Reynolds stresses for anisotropic turbulent flows were obtained. A refined wall function was employed to treat solid wall boundaries. The equations for 2D suspended load motion and sorting of bed material have been expanded into 3. cases. Numerical results are validated by the measured data of the Gezhouba Project, and proved to be in good agreement with the experimental. The present method has been employed to simulate sediment erosion and deposition in the dam area of Three Gorges Project, and for the operation of the project, siltation process and deposition pattern in the near-dam area of the reservoir, size distribution of the deposits and bed material, and flow fields and sediment concentration fields at different time and elevations are predicted. The predicted results are close to the experimental observations in physical model studies. Thus, a new method is established for 3. simulation of sediment motion in dam areas of multi-purpose water projects.

关键词： turbulent flows, Dou's stochastic theory, nonuniform suspended load, riverbed erosion and deposition, 3. mathematical model, Three Gorges Project.

INFLUENCE OF SEEPAGE FACE OBLIQUITY ON DISCHARGE OF GROUNDWATER AND ITS POLLUTANT INTO LAKE FROM A TYPICAL UNCONFINED AQUIFER

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Journal of Hydrodynamics 2007年第6期19卷 756-761页

作者： LI Yong WANG Chao YANG Lin-zhang LI Yi-ping State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing 210098 China College of environmental science and engineering Hohai University Nanjing 210098 China Institute of Soil science Chinese Academy of Sciences Nanjing 210008 China

Lab experiment and mathematical simulation Modular three dimensional finite difference groundwater （MODFLOW） were performed in a soil tank to simulate the hydrogeochemical interaction between lake and typical unconfined aquifer. Results show that the velocity decreases exponentially with the transect distance on seepage face. The maximal velocity occurs at the top point of seepage face. The obliquity of seepage face has a great influence on the maximum and distribution of seepage velocity. With the increase of the obliquity of seepage face, the maximal velocity decreases quickly and the velocity distribution becomes much more even. Most of groundwater flow and pollutant flux discharges through a narrow portion near the top of seepage face. The flow and mass concentrated in the narrow portion increase with the decrease of the obliquity of seepage face. These will benefit to design a reasonable and economical scenario to manage lakeshore and to control the pollution of lake water near lakeshore.

关键词： shallow lake unconfined aquifer groundwater discharge velocity distribution chloride MODFLOW

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,{3. 2 State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, nanjing university, nanjing 210093,{3. 3.Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of environmental science and engineering, Tongji university, Shanghai 200092,{3. College of Chemistry and Environment Nanjing Normal UniversityNanjing 210097China 2 State Key Laboratory of Pollution Control and Resources Reuse School of the EnvironmentNanjing UniversityNanjing 210093China Key Laboratory of Yangtze Aquatic En

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 <,- C not <,-O-.The high values of r2 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

Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a department of Earth sciences,nanjing {3.,nanjing 210093,china b College of Resource and environmental engineering,Guizhou {3.(Caijiaguan Campus),Guiyang 550003.china c nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,nanjing 210008,china department of Earth sciences Nanjing University Nanjing 210093 China College of Resource and environmental engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13.h pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

Study on Tribological Properties of Irradiated Crosslinking UHMWPE Nano-Composite

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Journal of Bionic engineering 2009年第1期6卷 7-13页

作者： Lei Xiong, Dang-sheng Xiong, Jia-bo Jindepartment of Materials science and engineering,{3. of science and Technology, nanjing 210094, P. R. china department of Materials science and engineering Nanjing University of Science and Technology Nanjing P. R. China

Ultra High Molecular Weight Polyethylene(UHMWPE)has been widely used as a bearing material for artificial joint replacement over forty *** is usually crosslinked by gamma rays irradiation before its implantation into human *** this study,UHMWPE and UHMWPE/nano-hydroxyapatite(n-HA)composite were prepared by vacuum hot-pressing *** prepared materials were irradiated by gamma rays in vacuum and molten heat treated in vacuum just after *** effect of filling n-HA with gamma irradiation on tribological properties of UHMWPE was investigated by using friction and wear experimental machine(model MM-200)under deionized water ***-morphology of worn surface was observed by metallographic *** angle and hardness of the materials were also *** results show that contact angle and hardness are changed by filling n-HA and gamma *** coefficient and wear rate under deionized water lubrication are reduced by filling *** friction coefficient is increased and wear rate is reduced significantly by gamma *** worn surface of unfilled material is mainly characterized as adhesive wear and abrasive wear,and that of n-HA filled material is mainly characterized as abrasive *** gamma irradiation,the degrees of adhesive and abrasive wear for unfilled material and abrasive wear of n-HA filled material are significantly *** and filled materials after irradiation are mainly shown as slight fatigue *** results indicate that UHMWPE and UHMWPE/n-HA irradiated at the dose of 150 kGy can be used as bearing materials in artificial joints for its excellent wear resistance compared to original UHMWPE.

关键词： tribological properties irradiated crosslinking UHMWPE n-HA artificial joints

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2, BI GuangGuo3.& XU WeiYe4 1 College of Information science and Technology, nanjing university of Aeronautics and Astronautics, nanjing 210016,{3. 2 department of Electronic engineering, City university of Hong Kong, Hong Kong,{3. 3.National Mobile Communications Research Laboratory, Southeast university, nanjing 210096,{3. 4 department of Communication engineering, nanjing Institute of Technology, nanjing 211167,{3. College of Information science and Technology Nanjing University of Aeronautics and Astronautics department of Electronic engineering City University of Hong Kong National Mobile Communications Research Laboratory Southeast University department of

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

Evaluation of zeolites synthesized from fly ash as potential adsorbents for wastewater containing heavy metals

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Journal of environmental sciences 2009年第1期21卷 127-136页

作者： WANG Chunfeng,LI Jiansheng,SUN Xia,WANG Lianjun,SUN XiuyunSchool of Chemical engineering,nanjing university of {3. and Technology,nanjing 210094,china. School of Chemical engineering Nanjing University of Science and Technology Nanjing 210094 China

The pure-form zeolites （A and X） were synthesized by applying a two-stage method during hydrothermal treatment of fly ash prepared initial Cu and Zn gel. The difference of adsorption capacity of both synthesized zeolits was assessed using Cu and Zn as target heavy metal ions. It was found that adsorption capacity of zeolite A showed much higher value than that of zeolite X. Thus, attention was focused on investigating the removal performance of heavy metal ions in aqueous solution on zeolite A, comparing with zeolite HS （hydroxyl-solidate） prepared from the residual fly ash （after synthesis of pure-form zeolite A from fly ash） and a commercial grade zeolite A. Batch method was used to study the influential parameters of the adsorption process. The equilibrium data were well fitted by the Langmuir model. The removal mechanism of metal ions followed adsorption and ion exchange processes. Attempts were also made to recover heavy metal ions and regenerate adsorbents.

关键词： fly ash zeolite heavy metal adsorption recovery

New progress of lake sediments and environmental changes research in china

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Chinese science Bulletin 1999年第19期44卷 1744-1754页

作者： WANG Sumin and ZHANG ZhenkeLaboratory of Lake Sediment and Environment, nanjing Institute of Geography and Limnology, Chinese Academy of sciences , nanjing 210008,{3. department of Geography and Oceanology, nanjing university , nanjing 210093 ,{3. Laboratory of Lake Sediment and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China department of Geography and Oceanology Nanjing University Nanjing China

environmental change recorded by lake sediments is one of the important branches of the past global changes study. The new progress of lake sediments and environmental changes in china since the late 1980s has been comprehensively discussed. The highlights emphasized are Asian paleomonsoon migration reflected by lake level fluctuation, uplift of the Qinghai-Xizang Plateau recorded by lacustrine sediments, saltlake sediments and

关键词： lake sediments environmental change.