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Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2, XIE Zheng-Hui1,* 2, LIU Qian1 and XIA Jun 3 1LASG, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029 (china). 2 college of Water resources and Environment, Hohai university, nanjing 210098 (china)3 Institute of Geographical science & Natural resources, Chinese Academy of sciences, Beijing 100101 (china) Institute of Atmospheric Physics Chinese Academy of Sciences LASG CAS Beijing 100029 Institute of Geographical science & Natural resources Chinese Academy of Sciences Beijing 100101

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3L model

Detection of subcritical crack propagation for concrete dams

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science china(Technological sciences) 2009年第12期52卷 3654-3660页

作者： BAO TengFei1 ,2&YU Hong 1,2 1college of Water Conservancy&Hydropower Engineering,Hohai university,nanjing 210098,china 2National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety,nanjing 210098,china college of Water Conservancy & Hydropower Engineering Hohai University Nanjing China National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety Nanjing China

Subcritical propagation of cracks is a warning sign of *** such propagation is detected at an early stage,timely maintenance measures can be taken to prevent the failure of *** detect the subcritical propagation of a crack,the crack needs to be monitored continuously in a long term, which is not realistic under certain ***,cracks in concrete dams can be monitored continuously by dam monitoring to offer possible detection for subcritical *** this paper, with measured crack openings from dam monitoring,a state equation for characterizing crack development is established based on the grey system *** relation between the stability of the equation and the subcritical crack propagation is investigated,then a criterion is proposed for detecting subcritical *** example demonstrates the validity of the criterion and its potential for practical application.

关键词： crack subcritical propagation criterion concrete

Variation of δ^(13)C in karst soil in Yaji Karst Experiment Site, Guilin

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Chinese science Bulletin 2002年第6期47卷 500-503页

作者： PAN Genxing, HE Shiyi, CAO Jianhua, TAO Yuxiang & SUN Yuhuacollege of Resource and Environment science, nanjing agricultural university, nanjing 2.0095, china Karst Dyanmics Laboratory, Ministry of Land and resources, Guilin 541004, china college of Resource and Environment science Nanjing Agricultural University Nanjing China Karst Dyanmics Laboratory Ministry of Land and Resources Guilin China

This study deals with δ13C variation in karst soil system of Yaji Karst Experiment Site, Guilin, a typical region of humid subtropical karst formations. Samples of near ground air, plant tissue, soil and water (soil solution and karst spring) were respectively collected on site in different seasons during 1996-1999. Considerable variation of δ13C values are not only found with different carbon pools of soil organic carbon, soil air CO2 and soil water HCO3-, but also with the soil depths and with different seasons during a year. The δ13C values of CO2 both of near ground air and soil air are lower in July than those in April by 1‰-4‰ PDB. Our results indicate that the δ13C values of carbon in the water and air are essentially dependent on interface carbon interaction of air-plant-soil-rock-water governed by soilorganic carbon and soil CO2 in the system.

关键词： karst soil carbon δ13C.

Effect of Bacterial-Feeding Nematode Inoculation on Wheat Growth and N and P Uptake

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Pedosphere 2001年第1期11卷 57-62页

作者： LIHULXIN HUFENG collegeofresourcesandEnvironmentalsciencesandInstituteofAgiculturalresourcesandEco－environment NanjingAgriculturalUniversityNanjing210095（China） collegeofresourcesandEnvironmentalsciencesandInstitute

A 40-day gnotobiotic microcosm experiment was carried out to quantify the effect of hastenal-feeding nematode on plant growth and nutrient absorption. The results showed that inoculation of bacterial-feeding nematode Protorhabditis sp. stimulated the growth of wheat (Triticum aestivum) and the uptake of N. By the end of the 40-day incubation wheat biomass and N uptake in the treatment with nematode and bacteria (Pseudomonas sp.) increased by 6.5% and 5.9%, respectively, compared with bacteria alone treatment. The presence of nematode mainly accelerated the growth of aboveground of wheat, while it slightly inhibited the root development. There was little difference in plant tissue N concentration between treatments. P concentration and uptake of wheat, however, were generally reduced by nematode. It appears that the enhancement of plant growth and nitrogen uptake is attributed to the enhancement of nitrogen mineralization induced by nematode feeding on bacteria, and the reduction of phosphorous uptake is the result of weak root status and competition by bacteria immobilization.

关键词： bacterial-feeding nematode nematode-bacteria interaction nitrogen and phosphorous uptake wheat growth

HYDROELASTIC VIBRATIONS AND LIQUID SLOSHING SUPPRESSION IN A RECTANGULAR TANK WITH ELASTIC SPACER

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Journal of Hydrodynamics 2004年第3期16卷 336-340页

作者： CHENGXu-duo LIANGYong WENJi-hua SchoolofFoodscienceandEngineering NanjingUniversityofFinanceandEconomicsNanjing210003China

In this paper, the couple vibration of liquid and elastic spacer in arectangular tank is investigated. Two different velocity potential functions correspondingrespectively to the liquid above and below the elastic spacer are assumed. Complicated boundaryconditions corresponding to two velocity potential functions and vibrations of elastic spacer aregiven. Using the method of energy, the equation of couple frequency is obtained. Through numericalcomputation the natural frequencies that change according to the location and stiffness of thespacer are shown.

关键词： system dynamics liquid-solid coupling sloshing suppression liquid-filledspacecraft

Analysis of variance for testing method of cement in determination of strength

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Progress in Natural science:Materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of Materials-Oriented Chemical Engineering,college of Material science and Engineering, nanjing university of Technology,nanjing 210009,china State Key Laboratory of Materials-Oriented Chemical Engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

Partial discharge-induced crack growth in dielectric materials

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 886-891页

作者： LUO JiaCheng,GAO CunFa & DAI XiangHua college of Aerospace Engineering,nanjing university of Aeronautics & Astronautics,nanjing 210016,china college of Aerospace Engineering Nanjing University of Aeronautics & Astronautics Nanjing China

Partial discharge(PD) of an air-filled semi-permeable crack in a dielectric material is studied based on the streamer-type discharge mechanism to explore the effects of applied mechanical-electric fields on crack *** the frame of two-dimensional deformation,the electric field inside the crack is first derived by taking the crack deformation into ***,the effects of electric field before PD are discussed through considering the contribution of the induced electric field inside the deformed crack space to the total energy release ***,PD and its effects on crack growth are *** is found that:(1) before PD,the applied electric field always retards crack growth;(2) during PD,the applied electric field can induce crack growth in dielectric materials.

关键词： crack dielectric materials partial discharge electric field effects

Damage and progressive failure of concrete structures using non-local peridynamic modeling

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science china(Technological sciences) 2011年第3期54卷 591-596页

作者： HUANG Dan1,2, ZHANG Qing1,2 & QIAO PiZhong1,3 1 State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering, Hohai university, nanjing 210098, china 2 Department of Engineering Mechanics, Hohai university, nanjing 210098, china 3 Department of Civil and Environmental Engineering, Washington State university, Pullman, WA 99164-2910, USA State Key Laboratory of Hydrology-Water resources and Hydraulic Engineering Hohai University Nanjing China Department of Engineering Mechanics Hohai University Nanjing China Department of Civil and Environmental Engineering Washington State University Pullman USA

Peridynamics (PD), a recently developed theory of solid mechanics, which employs a non-local model of force interaction and makes use of integral formulation rather than the spatial partial differential equations used in the classical continuum mechanics theory, has shown effectiveness and promise in solving discontinuous problems at both macro and micro scales. In this paper, the peridynamics theory is used to analyze damage and progressive failure of concrete structures. A non-local peridynamic model for a rectangular concrete plate is developed, and a central pairwise force function is introduced to describe the interior interactions between particles within some definite distance. Damage initiation, evolution and crack propagation in the concrete model subject to in-plane uni-axial tension, in-plane uni-axial compression and out-of-plane impact load are investigated respectively. The numerical results show that discontinuities appear and grow spontaneously as part of the solution to the peridynamic equations of motion, and no special failure criteria or re-meshing techniques are required, which proves the potential of peridynamic modeling as a promising technique for analyzing the progressive failure of concrete materials and structures.

关键词： concrete damage progressive failure peridynamic model discontinuities

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:Materials International 2011年第3期21卷 246-253页

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design