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Dynamic calculation model and seismic response for frame supporting structure with prestressed anchors

science china(Technological sciences) 2010年第7期53卷 1957-1966页

作者： DONG JianHua1’2, ZHU YanPeng1, ZHOU Yong1 & MA Wei2 1 College of Civil Engineering, Lanzhou University of technology, Lanzhou 730050, china 2 State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions environmental and Engineering research Institute, Chinese Academy of sciences, Lanzhou 730000, china 1. College of Civil Engineering Lanzhou University of Technology Lanzhou 730050 China2. State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed. The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope. The lateral displacement of frame and soil is nearly in phase. The movement characteristic satisfies the theory of elastic foundation beam. The frame is treated with elastic foundation beam in this model. The influence of prestressed anchors is simplified as linear spring and damped system related with velocity. Under the condition of horizontal earthquake excitation, the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration. This method is applied to a case record for illustration of its capability, in order to verify the method, 3D nonlinear FEM (ADINA) is used to analyze the seismic performance of this case, the comparative results show that the design and the analysis are safe and credible by using the proposed method. The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.

关键词： frame supporting structure with prestressed anchor slope dynamic calculation model seismic performance seismic design

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ANALYTICAL MODELS OF FLOATING BRIDGES SUBJECTED BY MOVING LOADS FOR DIFFERENT WATER DEPTHS

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Journal of Hydrodynamics 2008年第5期20卷 537-546页

作者： ZHANG Jun MIAO Guo-ping LIU Jian-xun SUN Wen-jun The First Engineers Scientific research Institute of the General Armaments Department Wuxi 214035 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030China The First Engineers Scientific research Institute of the General Armaments Department Wuxi 214035 China

There are two types of floating bridge such as discrete-pontoon floating bridges and continuous-pontoon floating bridges. Analytical models of both floating bridges subjected by raoving loads are presented to study the dynamic responses with hydrodynamic influence coefficients for different water depths. The beam theory and potential theory are introduced to produce the models. The hydrodynamic coefficients and dynamic responses of bridges are evaluated by the boundary element method and by the Galerkin method of weighted residuals, respectively. Considering causal relationship between the frequencies of the oscillation of floating bridges and the added mass coefficients, an iteration method is introduced to compute hydrodynamic frequencies. The results indicate that water depth has little influence upon the dynamic responses of both types of floating bridges, so that the effect of water depth can be neglected during the course of designing floating bridges.

关键词： floating bridge analytical model moving load water depth

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Influence of organic amendments on the sorption of pentachlorophenol on soils

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Journal of environmental sciences 2009年第4期21卷 474-480页

作者： LI Ruijuan, WEN Bei, ZHANG Shuzhen, PEI Zhiguo, SHAN Xiaoquan State Key Laboratory of environmental Chemistry and Ecotoxicology, research center for Eco-environmental sciences, Chinese Academy of sciences,Beijing 100085, china [a]State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influence of pH on the sorption of pentachlorophenol （PCP） onto three organic amendments, char, humic acid （HA） and peat, and the effect of organic amendments on PCP sorption to three kinds of soils were evaluated. The sorption of PCP on these sorbents fitted the Freundlich model well, suggesting that PCP sorption isotherms were nonlinear with exponential coefficient （N） value lower than 1. The PCP sorption capacity on three organic amendments and the N values increased with decreasing pH. The sorption capacities were in the order： char 〉 HA 〉 peat. Organic amendments resulted in an enhancement of sorption capacities of soils. The N values of PCP sorption on soils were decreased by char amendment and increased by HA and peat amendments. This study demonstrated that application of traditional organic amendments led to the enhancement of PCP sorption by soils. This information may aid both in predicting environmental fates of hydrophobic ionizable organic compounds and in developing remediation strategies for them.

关键词： sorption pentachlorophenol char peat humic acid pH

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Fate　of　pesticide　N’-(2,4-dimethylphenyl)-N-methylformamide　hydrochloride　in　simulated　aquatic　ecosystem

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Journal of environmental sciences 1997年第3期9卷 119-122页

作者： Yang Kewu, Mo Hanhong, An Fengchun research center for Eco environmental sciences, Chinese Academy of science, Beijing 100085, china

The degradation and fate of pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride in simulated aquatic ecosystem were investigated. The results showed that the pesticide was not stable in simulated aquatic ecosystem with pH value of 7.4—8.9 and water temperature of 18.0—26.5℃. In the first 9 days, 95% of DMAH was disappeared, whereas the concentration of its degradation product 2,4 dimethylformanilide increased with time and was of a maximum value at about 9 days and then decreased. The concentration of 2, 4 dimethylaniline, which is another degradation product of DMAH, nearly did not change in the early of experiment. However, it decreased rapidly after 9 days. The experiment lasted 51 days. At the end of experiment, there were no N' 2, 4 dimethylphenyl) N methylformamidine, 2, 4 dimethylformanilide and 2, 4 dimethylaniline detected in water, but they were all detected in the sediment and water grass, and the total amount of them covered 2%—3% of application amount of DMAH. It indicated that water grass and sediment could absorb and concentrate these compounds.

关键词： pesticide N' (2,4 dimethylphenyl) N methylformamidine hydrochloride hydrolysis 2,4 dimethylformanilide 2,4 dimethylaniline.

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Understanding the endocrine disruption of chiral pesticides:The enantioselectivity in estrogenic activity of synthetic pyrethroids

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science china Chemistry 2010年第5期53卷 1003-1009页

作者： WANG Cui 1,ZHANG Quan 1,ZHANG XiaoFeng 1,LIU Jing 2 & LIU WeiPing 2 1College of Biological and environmental Engineering,Zhejiang University of technology,Hangzhou 310032,china 2Key Laboratory of environmental Remediation and Ecosystem Health,Ministry of Education College of environmental and Resource sciences,Zhejiang University,Hangzhou 310029,china 1. College of Biological and environmental Engineering Zhejiang University of Technology Hangzhou 310032 China2. Key Laboratory of Environmental Remediation and Ecosystem Health Ministry of Education College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p2R-Fen and αS-2S-Fen also induced the β-galactosidase *** inability to initiate the reporter gene expression by the racemic chemicals may be due to the low ratios of these isomers or the antagonism among *** strong hydrophobic interaction and the hydrogen bond between positive estrogenic isomers and ERα support our biological testing *** research demonstrated that the enantioselective estrogenic activity of chiral SPs was due to selective binding between their isomers and the ERα*** data suggests that enantioselectivity of these chiral pesticides is significant to their estrogenic activities.

关键词： enantioselectivity synthetic pyrethroids (SPs) endocrine disruption yeast molecular docking

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Levels and distributions of polychlorinated biphenyls in sewage sludge of urban wastewater treatment plants

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Journal of environmental sciences 2009年第4期21卷 468-473页

作者： GUO Li, ZHANG Bing, XIAO Ke, ZHANG Qinghua, ZHENG Minghui State Key Laboratory of environmental Chemistry and Ecotoxicology, research center for Eco-environmental sciences, Chinese Academy of sciences,Beijing 100085, china [a]State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Concentrations of polychlorinated biphenyls （PCBs） have been measured in sewage sludge samples from 8 urban wastewater treatment plants in Beijing, china. The PCB congeners were analyzed by isotope dilution high resolution gas chromatography/high resolution mass spectrometry method. The concentration of PCBs ranged from 65.6 to 157 ng/g dry weight （dw）, with a mean value of 101 ng/g dw. The dioxin-like PCB WHO-TEQs （World Health Organization-Toxic Equivalents） of the sludge were lower than 1 pg /g dw. Consequently, all the concentrations of PCBs in sludge samples were below the upper limit for land application according to the Chinese legislation law for agriculture use. The PCB homologue profiles in sludge samples were dominated by tri-CBs and tetra- CBs. Similar distributions have been found in one of the Chinese PCB commercial products. The patterns of dioxin-like and indicator congeners observed in this study were quite similar in all samples. The predominant congener for dioxin-like and indicator PCBs were PCB-118 and PCB-28, respectively, while PCB-126 had the highest TEQ value.

关键词： polychlorinated biphenyls wastewater treatment plant sewage sludge distribution

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Exploring the Mechanical Properties,Shrinkage and Compensation Mechanism of Cement Stabilized Macadam-Steel Slag from Multiple Perspectives

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Journal of Renewable Materials 2023年第5期11卷 2513-2529页

作者： Wei Zhang Mulian Zheng Yifeng Li wuxi Zheng Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang’an UniversityXi’an710064China Rizhao Transportation Management center Rizhao27680China Central-South Safety&Environment technology Institute Co. Ltd.Wuhan43000China

Steel slag is characterized by high strength,good wear resistance and *** study aims at exploring the potential of steel slag in cement stabilized aggregates,mainly including mechanical properties,shrinkage and compensation *** this purpose,the compressive strength and compressive resilient modulus of cement stabilized aggregates with different steel slag contents(CSMS)were initially ***,the effects of steel slag and cement on dry shrinkage,temperature shrinkage,and total shrinkage were analyzed through a series of shrinkage test ***,in combination with X-ray diffraction(XRD)and Scanning electron microscope(SEM),the characteristic peaks and microscopic images of cement,steel slag and cement-steel slag at different hydration ages were analyzed to identify the chemical substances causing the expansion volume of steel slag and reveal the compensation mechanism of *** results show that the introduction of 20%steel slag improved the mechanical properties of CSMS by 16.7%,reduced dry shrinkage by 21%,increased temperature shrinkage by 5.8%and reduced its total shrinkage by 19.2%.Compared with the hydration reaction of cement alone,the composite hydration reaction of steel slag with cement does not produce new ***,it is noteworthy that the volume expansion of the f-CaO hydration reaction in steel slag can compensate for the volume shrinkage of cement-stabilized *** research can provide a solid theoretical basis for the application and promotion of steel slag in cement-stabilized macadam and reduce the possibility of shrinkage cracking.

关键词： Cement stabilized macadam-steel slag compensate mechanical properties pavement base shrinkage steel slag

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Designing regional pattern for ecosystem restoration:A case study

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science china(Technological sciences) 2006年第z1期49卷 86-97页

作者： LI Guoqiang , MA Keming, FU Bojie & LIU Shiling State Key Lab of Systems Ecology, research center for Eco-environmental sciences, Chinese Academy of sciences, Beijing 100085, china Department of Water Environment, china Institute of Water Resources and Hydropower research, Beijing 100038, china School of environmental sciences, Beijing Normal University, Beijing 100875, china 1. State Key Lab of Systems Ecology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. Department of Water Environment China Institute of Water Resources and Hydropower Research Beijing 100038 China 3. School of environmental sciences Beijing Normal University Beijing 100875 China

Designing regional pattern is challenging for ecosystem restoration both in theory and in practice. The present study proposed a new approach to design regional pattern for ecosystem restoration with a case in the arid valley of Upper Minjiang River, SW china. The procedures are: (1) Determine the regional pattern of main environmental factors based on the relationships between the important environmental factors and the main geographical factors generated from DEM data. (2) Overlay the maps of the main environmental factors. (3) Generate a lookup table according to the species selection rule we proposed to link the candidate restoration species to the main environmental factors.(4) Determine the regional pattern of ecosystem restoration by positioning the restoration species in the map of environmental factors according to the lookup table. The regional restoration pattern designed in this way would be applicable not only to restoring a region, but also to predicting the future landscape change.

关键词： environmental factors, GIS, restoration species, Upper Minjiang River Valley.

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Exergy and ecological modelling of lake environment

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Journal of environmental sciences 1998年第4期10卷 114-121页

作者： Zhang Yong ze environmental Engineering center, Chinese research Academy of environmental sciences, Beijing 100012, china Wang Xuan Institute of environmental science, Beijing Normal University, Beijing 100875, china

The thermodynamic theories and ecological theories can be integrated effectively by exergy(biogeochemical energy of the system) to study the environmental problems of the lakes and reservoirs. In this paper, the applications of exergy in the ecological modelling of lake environment were reviewed. Results showed that exergy can be used as a goal function to estimate the parameters of the ecological model for lakes and reservoirs and to develop the structural dynamic models accounting for the changes in lake ecosystems, and as an ecological indicators for the development and evolution of lake ecosystems.

关键词： exergy ecological indicator structural dynamic model goal function.

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WAVES GENERATED BY A 3D MOVING BODY IN A TWO LAYER FLUID OF FINITE DEPTH

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Journal of Hydrodynamics 2005年第1期17卷 92-101页

作者： ZHUWei YOUYun-xiang MIAOGuo-ping ZHAOFeng ZHANGJun SchoolofNavalArchitecture OceanandCivilEngineeringShanghaiJiaotongUniversityShanghai200030China chinaShipScientificresearchcenter Wuxi214082China

This paper is concerned with the waves generated by a 3 D body advancing beneath the free surface with constant speed in a two layer fluid of finite depth. By applying Green’s theorem, a layered integral equation system based on the Rankine source for the perturbed velocity potential generated by the moving body was derived with the potential flow theory. A four node isoparametric element method was used to treat with the solution of the layered integral equation system. The surface and interface waves generated by a moving ball were calculated numerically. The results were compared with the analytical results for a moving source with constant velocity.

关键词： internal waves two-layer fluid Rankine source wave-making wave pattern

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