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sediment transport capacity of hyperconcentrated flow

Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2.& FEI XiangJun2.1 School of Environment & key laboratory of {2. and sediment sciences,ministry of education,Beijing Normal University,Beijing 100875,china 2.State key laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,china School of Environment & key laboratory of {2. and sediment sciences Ministry of Education Beijing Normal University Beijing 100875 China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity

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Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2. SHEN Zhenyao1 and LI Jianqiang3(1. State key laboratory of {2. Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, china 2. key laboratory for {2. and sediment sciences ministry of education, School of Environment, Beijing Normal University, Beijing 100875, china 3. {2. Resources and Hydropower Planning and Design General Institute, MWR, Beijing 100011, china) State key laboratory of {2. Environment Simulation School of Environment Beijing Normal University Beijing 100875 China key laboratory for {2. and sediment sciences ministry of education School of Environment Beijing Normal University Beijing 100875 China water Resources and Hydropower Planning and Design General Institute MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

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Analysis of china’s water Security and Virtual water Trade

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Chinese Journal of Population,Resources and Environment 2006年第4期4卷 18-23页

作者： Wang Hongrui1,2.Liu Xinghan3,Dong Yanyan1,2.Wang Junhong1,2.1.College of water sciences,Beijing Normal University,Beijing {2.,china 2.key laboratory for water and sediment sciences ministry of education,Beijing {2.,china 3.College of Economics&Management,Beijing University of Technology,Beijing 10002.,china College of water sciences Beijing Normal University Beijing 100875 China key laboratory for {2. and sediment sciences ministry of education Beijing 100875 China College of Economics & Management Beijing University of Technology Beijing 100022 China College of Water Sciences Beijing Normal University Beijing 100875 China key laboratory for {2. and sediment sciences ministry of education Beijing 100875 China College of water sciences Beijing Normal University Beijing 100875 China key laboratory for {2. and sediment sciences ministry of education Beijing 100875 China

Producing goods and services all needs water *** water used in the process of an agricultural or industrial product is called the"Virtual water"contained in this product. Through international trade,water-scarce countries and regions could purchase water-intensive products--especially foods,from water-rich countries to balance their water deficits and achieve water *** is one of the 13 most water-deficit countries whose water safety have been severely *** paper generalized the recent global research development and made a brief introduction about the methods calculating virtual water content in specific *** a case study,we qualified china's annual virtual water flows from year 2.00 to 2.02.with trade in crops,and ended with some policy advice for application and practice of virtual water strategy.

关键词： water security virtual water virtual water trade crops

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An ecological hydraulic radius approach to estimate the instream ecological water requirement

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Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( key laboratory of {2. Cycle and Related Land Surface Process, Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china key laboratory of {2. and sediment sciences, ministry of {12. & {2. sciences College, Beijing Normal University, Beijing 100875, china Department of Hydraulic and Hydropower Engineering, North china Electric Power University, Beijing 102.06, china) [a]key laboratory of {2. Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China [b]key laboratory of {2. and sediment sciences Ministry of Education & Water Sciences Gllege Beijing Noirnal University Beijing China [c]Departhent of Hydraulic and Hydropower Engineering North China Elecfric Power University Beijing China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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Development and application of ergodicity model with FRCM and FLAR for hydrological process

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Science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2. LIN Xin3 & ZENG WenYi4 1 College of water Science, key {2. for water and sediment sciences of the ministry of education, Beijing Normal University, Beijing 100875, china 2.School of Science, Beijing Institute of education, Beijing 100011, china 3 School of Mathematical sciences, Beijing Normal University, Beijing 100875, china 4 College of Information Science and Technology, Beijing Normal University, Beijing 100875, china 1. College of water Science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of Science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical sciences Beijing Normal University Beijing 100875 China 4. College of Information Science and Technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2.04) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

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An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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Science china(Technological sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2. SHEN Zhenyao1 & LI Jianqiang3 1. School of Environment, State key laboratory of {2. Environment Simulation, Beijing Normal Univer- sity, Beijing 100875, china 2. School of Environment, key laboratory for {2. and sediment sciences of ministry of education, Beijing Normal University, Beijing 100875, china 3. {2. Resources and Hydropower Planning and Design General Institute, MWR, Beijing 100011, china Beijing Normal Univ Sch Environm State Key Lab Water Environm Simulat Beijing 100875 Peoples R China Beijing Normal Univ Sch Environm Key Lab Water & Sediment Sci Minist Educ Beijing 100875 Peoples R China MWR Water Resources & Hydropower Planning & Design Ge Beijing 100011 Peoples R China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective Decision-Making (IIMMODM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMODM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMODM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMODM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.

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Problems in wavelet analysis of hydrologic series and some suggestions on improvement

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Progress in Natural Science:Materials International 2007年第1期17卷 80-86页

作者： WANG Hongrui, YE Letian, LIU Changming, YANG Chi and LIU Peng ( College of water sciences, Beijing Normal University, Beijing {2., china key laboratory for water and sediment sciences, ministry of education, Beijing {2., china School of Mathematical sciences, Peking University, Beijing 100089, china College of Engineering sciences, University of Region, Canada) [a]College of water sciences Beijing Normal University Beijing China [b]key laboratory for {2. and sediment sciences Ministry of Education Beijing China [c]School of Mathematical sciences Peking University Beijing China [d]College of Engineering sciences University of Region Canada

Applying the wavelet theory and methods to investigate the hydrologic processes such as precipitation and runoff is a hot field. However, several aspects in research are usually ignored: the effect of admissible condition of wavelet functions and the disturbance of noises for the detection of periods, the effect of the length of a hydrologic time-series on the final result, and the choice between the anomaly and the original time series for wavelet analysis. In this paper, these issues are fully discussed. Precipitation data from Lanzhou Precipitation Station are taken for case study. The result indicates that in the wavelet analysis of hydrologic series, denoise methods should be used to eliminate the influence of noises. The MexHat wavelet function satisfies the admissible condition, which ensures that the periodic properties of hydrologic processes can be well represented by using the MexHat wavelet for decomposition. The affected range of hydro-logic series which should be discarded before analysis is given. It is also suggested that the anomaly series should be used to highlight the actual undulation of the hydrologic series.

关键词： wavelet analysis hydrologic process admissible condition noise period.

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Paper sludge as a feasible soil amendment for the immobilization of Pb^(2.)

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Journal of Environmental sciences 2010年第3期22卷 413-420页

作者： Xiaojia He, Lei Yao, Zhu Liang, Jinren NiThe key laboratory of {2. and sediment sciences, ministry of education, Department of Environmental Engineering, Peking University, Beijing 100871, china. The key laboratory of {2. and sediment sciences Ministry of Education Department of Environmental Engineering Peking University Beijing 100871 China

The possibility of amending Pb 2. contaminated soil （S） with paper sludge （P） was investigated through adsorption and desorption experiments. The adsorption process of Pb 2. in soil containing paper sludge （SP） could be well described by pseudo second-order kinetic model and the Langmuir isotherm model. After P addition, the equilibrium time decreased greatly （from 2. to 8 hr） and the Pb 2. maximum adsorbed amount （Q max ） increased by a factor of more than three to 102.04 mg/g. Q max reached its maximum as S：P was 9：1 （m/m） after 10 days contact between S and P. Moreover, Pb 2. adsorbed amount increased with the rise of pH during the adsorption process. Desorption experiments indicated that Pb 2. adsorption in SP was irreversible. The metal ion fraction was analyzed with Energy Dispersive Spectrometer and Environmental Scan Electron Microscope. As a result, the addition of P to soil was found to induce a decrease in the mobile forms. The Pb 2. complexes formation in the presence of carbonates was the main adsorption mechanism. Overall, the paper sludge could be one of the promising soil amendments for the remediation of soil with Pb 2. contamination.

关键词： paper sludge pb^2. adsorption

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Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas

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Science china Earth sciences 2005年第7期48卷 849-862页

作者： ZHENG Yadong 1 & WANG Tao2.1. key laboratory of Orogenic Belts and Crustal Evolution (Peking University), {2. of education, Beijing 100871, china 2. Institute of Geology, Chinese Academy of Geological sciences, Beijing 100037, china key laboratory of Orogenic Belts and Crustal Evolution (Peking University) Ministry of Education Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijinq 100037 China

The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.10 and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 165°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ～66°, while the later average kinematic vorticity was ～0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.

关键词： Mesozoic thrusting,late-orogenic collapse,kinematic vorticity number,stress state.

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The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor

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Journal of Environmental sciences 2003年第3期15卷 423-432页

作者： ZHANG Dai-jun 1,2.(1. Department of Environmental Science, Chongqing University, Campus A, Chongqing 400044, china 2. key {2. for the Southwest china Resources Exploitation and Environmental Disaster Control Engineering, ministry of education, china.) Department of Environmental Science Chongqing University China

The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 107 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91% to 97% of COD were removed at up to about 3.9 g COD/(L·d) of COD volumetric loading rate. More than 97% to 100% of nitrite was denitrified at up to about 0.8 g NO -_2.N/(L·d), which is 16 times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05 gN/(L·d)). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 15 days with sludge from the reactor showed that 100% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 15% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis.

关键词： methanogenesis denitrification ANAMMOX EGSB reactor

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