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Efficiency of sediment transport by flood and its control in the Lower Yellow River

Science china(Technological sciences) 2004年第z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2. LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking University {2., ministry of education, Beijing 100871, china 2. General Institute of water Resources and Hydropower Planning and Design, ministry of water Re- sources, Beijing 100011, china 3. The Yellow River Conservancy Commission, Zhengzhou 450003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China 2. The key laboratory of {2. and sediment sciences Ministry of Education 100871 Beijing China 3. General Institute of water Resources and Hydropower Planning and Design Ministry of Water Resources 100011 Beijing China 4. The Yellow River Conservancy Commission 450003 Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on {2. Use for sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 2. kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 2. kg/m3, the optimized controlling discharge ranges from 2.90 to 2.00 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower Yellow River, flood, sediment transport, efficiency, simulation, control.

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On the variation of water resource structure in the Lower Yellow River

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Science china(Technological sciences) 2004年第z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, LI Tianhong1 & ZHAO Yean2.1. Department of Environmental Engineering, Peking University {2., ministry of education, Beijing 100871, china 2. Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China3. Institute of Hydraulic Research YellowRiver Conservancy Commission 450003 Zhengzhou China

In view of river functions and the Minimum water Demand for River Ecosystem (MWDRE), the water resources in the Lower Yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2.01 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the Yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

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Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science china(Technological sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN XiaoLing 1,2.3,YU ZhiFeng 1,XIAO JingJing 1,QIU Feng 1 & ZHAO Xi 1 1 State key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430079,{2. 2.0} laboratory of Poyang Lake Wetland and watershed Research,ministry of education,Jiangxi Normal University,Nanchang 33002.,{2. 3 The key laboratory of Poyang Lake Environment and Resource Utilization,ministry of education,Nanchang University,Nanchang 330031,{2. 1. State key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. key laboratory of Poyang Lake Wetland and {2.shed Research Ministry of Education Jiangxi Normal University Nanchang 330022 China 3. The key laboratory of Poyang Lake Environ{2. and Resource Utilization Ministry of Education Nanchang University Nanchang 330031 China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote sensing study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

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Preparation of Nanosized AlOOH and Its Application in Polymer-inorganic Nanocomposites

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 638-643页

作者：廖海达 State key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology College of Chemistry and Ecological Engineering Guangxi University for Nationalities key Lab of Nonferrous Materials and New Processing Technology (Guangxi University Guilin University of Technology) Ministry of Education

With industrial grade Al（OH）3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automatically disperse to a single-dispersing state in water without surface modification, dispersant, additive and accessional conditions （ultrasonic wave dispersing, ball-mill dispersing）. The application results of the product indicate that the nanosized AlOOH can be composed into a toughened nanocomposites without surface modification. Accordingly, the self dispersion characteristic and mechanism of hydrothermal crystallization and charging composite dispersion of nanosized AIOOH are found, and a new technique of preparing polymer/inorganic nanocomposites is proposed, which is called blending compositing new techniques of sol even dispersing at auasi-homogeneous phase.

关键词： self dispersion nanosized AlOOH peptizing-hydrothermal method nanocomposites

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Determination of decabromodiphenyl ether in water samples by single-drop microextraction and RPHPLC

Determination of decabromodiphenyl ether in water samples by...

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中国化学会第十四届有机分析及生物分析学术研讨会

作者： LI Yan-yan FU Ling-yan WANG Xue-dong~* ZHANG Tao-zhi (key laboratory of Pesticide & Chemical Biology of{2. Central china Normal University)

＜正＞This paper describes the development of a new method using single-drop microextraction （SDME） and RP-HPLC for the determination of decabromodiphenyl ether （BDE-2.9） in water samples. The effects of SDME parameters such as extraction solvent,microdrop volume,extraction time,stirring speed,salt concentration,and sample pH on the extraction performance are *** optimal extraction conditions （extraction solvent,toluene;solvent drop volume,3.0 μL;extraction time,15 min;stirring speed,600 rpm;no addition of salt and change of sample pH）,the calibration curve was drawn by plotting peak area against a series of BDE-2.9 concentrations （0.001～1 μg/mL） in aqueous solution;the correlation coefficient （r） was *** limit of detection was 0.7 ng/*** enrich- ment factor was *** precision of this method was obtained by six successive analyses of a 100 ng/ mL standard solution of BDE-2.9,and BSD was 4.8%.This method was successfully applied to the ex- traction of BDE-2.9 from tap and east lake water samples with relative recoveries ranging from 92.5% to 102.8% and from 91.5% to 96.2.,respectively,and the relative standard deviations （a=3） were 4.4% and 2.2..The proposed method is acceptable for the analysis of BDE-2.9 in water samples.

关键词： Decabromodiphenyl ether Reversed phase high performance liquid chromatography Single drop microextraction water samples

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利用GPS进行切沟侵蚀监测研究

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水土保持学报 2004年第5期18卷 91-94页

作者：游智敏伍永秋刘宝元北京师范大学沙漠与沙区资源研究所北京师范大学地理与遥感科学学院北京100875

切沟侵蚀在土壤侵蚀中占据重要位置,切沟侵蚀监测研究是切沟侵蚀研究的重要方面。目前进行切沟侵蚀监测研究主要利用摄影测量的方法,该方法存在一定的局限性。对利用GPS进行切沟侵蚀监测研究进行了探讨,对切沟在不同时间进行测量,获得... 详细信息

切沟侵蚀在土壤侵蚀中占据重要位置,切沟侵蚀监测研究是切沟侵蚀研究的重要方面。目前进行切沟侵蚀监测研究主要利用摄影测量的方法,该方法存在一定的局限性。对利用GPS进行切沟侵蚀监测研究进行了探讨,对切沟在不同时间进行测量,获得多个时相的DEM,通过对比不同时相的DEM来获取该时间段的切沟侵蚀变化。最后以位于黑龙江省漫川漫岗黑土区的丰产电流域的一条切沟为研究实例,建立了2.02.2.03年10月两个时段分辨率为0.4 m的DEM,对比这两个时段的数据表明,该切沟沟头后退达13.78 m,侵蚀面积增大了711m^2.切沟的土壤侵蚀量增加了2.77 m^3,展示了GPS在切沟侵蚀研究中精度高、速度快等优越性,可为切沟侵蚀监测研究提供参考。

关键词： GPS 切沟侵蚀监测土壤侵蚀精度

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黄土丘陵沟壑区第五副区产沙机制初步分析

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水利学报 2018年第3期49卷 282-290页

作者：刘晓燕董国涛高云飞夏润亮孙一党素珍黄河水利委员会河南郑州450003 黄河水利科学研究院河南郑州450003 黄河上中游管理局陕西西安710021

黄土丘陵沟壑区第五副区主要分布在黄土高原西北部,是黄河流域的主要产沙区之一。通过实地调查,结合下垫面、降雨和水文实测数据,本文分析了该区泥沙来源、产沙特点及其影响因素,揭示了该区的产沙机制。实地调查表明,黄土丘陵沟壑区第... 详细信息

黄土丘陵沟壑区第五副区主要分布在黄土高原西北部,是黄河流域的主要产沙区之一。通过实地调查,结合下垫面、降雨和水文实测数据,本文分析了该区泥沙来源、产沙特点及其影响因素,揭示了该区的产沙机制。实地调查表明,黄土丘陵沟壑区第五副区大体是黄土丘陵和黄土台塬的结合产物,地表光滑的黄土丘陵群包围着一片黄土盆地或阶地是其地形特点,土壤疏松、植被稀疏是其地貌特点,雨量和雨强小、蒸发强是其气候特点。该区泥沙不仅产自周边丘陵,且相当部分来自中部盆地的河(沟)岸崩塌或滑坡,是黄土高原河沟侵蚀最剧烈的地方,有些河流的河沟产沙占比甚至高达2.3;从支毛沟,到干沟和河道,随着汇入水量的增加,产沙强度逐级增大。周边丘陵所产洪水是河(沟)岸崩塌或滑坡的主要动力,其植被覆盖或梯田规模是影响产洪的关键因素。该区产洪能力偏低,但洪水的含沙量高、且很难显著降低。

关键词：黄土丘陵第五副区气候下垫面泥沙来源产沙机制

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岸坡崩塌条件下弯道环流与水流剪切力的变化特征

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水利学报 2018年第3期49卷 271-281页

作者：舒安平周星余明辉段国胜朱福杨北京师范大学环境学院水沙科学教育部重点实验室北京100875 北京市水科学技术研究院北京100048 武汉大学水利水电学院湖北武汉430072

河岸崩塌(又称为崩岸或塌岸)是水动力作用下岸坡失稳的一种主要形式,属于一种典型的水力与重力的复合侵蚀。本文采用黄河上游宁蒙河段的磴口黏性河岸沙为实验用沙,通过实施8组弯道水槽实验模拟塌岸过程与河道冲淤演变过程,重点观测并分... 详细信息

河岸崩塌(又称为崩岸或塌岸)是水动力作用下岸坡失稳的一种主要形式,属于一种典型的水力与重力的复合侵蚀。本文采用黄河上游宁蒙河段的磴口黏性河岸沙为实验用沙,通过实施8组弯道水槽实验模拟塌岸过程与河道冲淤演变过程,重点观测并分析崩塌近岸水位、流速、颗粒粒径及河床冲淤形态等水力-泥沙-河床三方面因子变化特点,揭示黏性岸坡崩塌过程水流剪切力分布特征及其对河道冲淤形态影响机制,结果显示崩塌体头尾部的剪切力突增,形成较大剪切力区,尾部剪切力大于头部剪切力,尾部形成涡流,流速分布混乱,加快崩塌体的分解和崩塌进程。实验进一步揭示了崩塌过程河床形态对水流剪切力的响应关系,为建立崩塌河段泥沙输移模型提供了基础依据,并可供河道整治工程规划设计参考。

关键词：岸坡崩塌黏性岸坡水槽实验弯道环流水流剪切力

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Feasibility and physics potential of detecting ^(8)B solar neutrinos at JUNO

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Chinese Physics C 2021年第2期45卷 93-110页

作者： Angel Abusleme Thomas Adam Shakeel Ahmad Sebastiano Aiello Muhammad Akram Nawab Ali Fengpeng An Guangpeng An Qi An Giuseppe Andronico Nikolay Anfimov Vito Antonelli Tatiana Antoshkina Burin Asavapibhop João Pedro Athayde Marcondes de André Didier Auguste Andrej Babic Wander Baldini Andrea Barresi Eric Baussan Marco Bellato Antonio Bergnoli Enrico Bernieri David Biare Thilo Birkenfeld Sylvie Blin David Blum Simon Blyth Anastasia Bolshakova Mathieu Bongrand Clément Bordereau Dominique Breton Augusto Brigatti Riccardo Brugnera Riccardo Bruno Antonio Budano Max Buesken Mario Buscemi Jose Busto Ilya Butorov Anatael Cabrera Hao Cai Xiao Cai Yanke Cai Zhiyan Cai Antonio Cammi Agustin Campeny Chuanya Cao Guofu Cao Jun Cao Rossella Caruso Cédric Cerna Jinfan Chang Yun Chang Pingping Chen Po-An Chen Shaomin Chen Shenjian Chen Xurong Chen Yi-Wen Chen Yixue Chen Yu Chen Zhang Chen Jie Cheng Yaping Cheng Alexander Chepurnov Davide Chiesa Pietro Chimenti Artem Chukanov Anna Chuvashova Gérard Claverie Catia Clementi Barbara Clerbaux Selma Conforti Di Lorenzo Daniele Corti Salvatore Costa Flavio Dal Corso Christophe De La Taille Jiawei Deng Zhi Deng Ziyan Deng Wilfried Depnering Marco Diaz Xuefeng Ding Yayun Ding Bayu Dirgantara Sergey Dmitrievsky Tadeas Dohnal Georgy Donchenko Jianmeng Dong Damien Dornic Evgeny Doroshkevich Marcos Dracos Frédéric Druillole Shuxian Du Stefano Dusini Martin Dvorak Timo Enqvist Heike Enzmann Andrea Fabbri Lukas Fajt Donghua Fan Lei Fan Can Fang Jian Fang Marco Fargetta Anna Fatkina Dmitry Fedoseev Vladko Fekete Li-Cheng Feng Qichun Feng Richard Ford Andrey Formozov Amélie Fournier Haonan Gan Feng Gao Alberto Garfagnini Alexandre Göttel Christoph Genster Marco Giammarchi Agnese Giaz Nunzio Giudice Franco Giuliani Maxim Gonchar Guanghua Gong Hui Gong Oleg Gorchakov Yuri Gornushkin Marco Grassi Christian Grewing Maxim Gromov Vasily Gromov Minghao Gu Xiaofei Gu Yu Gu Mengyun Guan Nunzio Guardone Maria Gul Cong Guo Jingyuan Guo Wanlei Guo Xinheng Guo Yuhang Guo Paul Hackspacher Caren Hagner Ran Han Yan Yerevan Physics Institute YerevanArmenia UniversitéLibre de Bruxelles BrusselsBelgium Universidade Estadual de Londrina LondrinaBrazil Pontificia Universidade Catolica do Rio de Janeiro RioBrazil Pontificia Universidad Católica de Chile SantiagoChile Universidad Tecnica Federico Santa Maria ValparaisoChile Beijing Institute of Spacecraft Environment Engineering BeijingChina Beijing Normal University BeijingChina china Institute of Atomic Energy BeijingChina Institute of High Energy Physics BeijingChina North china Electric Power University BeijingChina School of Physics Peking UniversityBeijingChina Tsinghua University BeijingChina University of Chinese Academy of sciences BeijingChina Jilin University ChangchunChina College of Electronic Science and Engineering National University of Defense TechnologyChangshaChina Chongqing University ChongqingChina Dongguan University of Technology DongguanChina Jinan University GuangzhouChina Sun Yat-Sen University GuangzhouChina Harbin Institute of Technology HarbinChina University of Science and Technology of china HefeiChina The Radiochemistry and Nuclear Chemistry Group in University of South china HengyangChina Wuyi University JiangmenChina Shandong University JinanChina Institute of Modern Physics Chinese Academy of SciencesLanzhouChina Nanjing University NanjingChina Guangxi University NanningChina East china University of Science and Technology ShanghaiChina School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuangChina Nankai University TianjinChina Wuhan University WuhanChina Xi’an Jiaotong University Xi’anChina Xiamen University XiamenChina School of Physics and Microelectronics Zhengzhou UniversityZhengzhouChina Institute of Physics National Chiao-Tung University Hsinchu National United University Miao-Li Department of Physics National T

The Jiangmen Underground Neutrino Observatory(JUNO)features a 2. kt multi-purpose underground liquid scintillator sphere as its main *** of JUNO's features make it an excellent location for^8B solar neutrino measurements,such as its low-energy threshold,high energy resolution compared with water Cherenkov detectors,and much larger target mass compared with previous liquid scintillator *** this paper,we present a comprehensive assessment of JUNO's potential for detecting^8B solar neutrinos via the neutrino-electron elastic scattering process.A reduced 2.MeV threshold for the recoil electron energy is found to be achievable,assuming that the intrinsic radioactive background^(2.8)U and^(2.2.Th in the liquid scintillator can be controlled to 10^(-17)g/*** ten years of data acquisition,approximately 60,000 signal and 30,000 background events are *** large sample will enable an examination of the distortion of the recoil electron spectrum that is dominated by the neutrino flavor transformation in the dense solar matter,which will shed new light on the inconsistency between the measured electron spectra and the predictions of the standard three-flavor neutrino oscillation *** m^(2._(2.)=4.8times10^(-5);(7.5times10^(-5))eV^(2.,JUNO can provide evidence of neutrino oscillation in the Earth at approximately the 3sigma(2.igma)level by measuring the non-zero signal rate variation with respect to the solar zenith ***,JUNO can simultaneously measureDelta m^2.(2.)using^8B solar neutrinos to a precision of 2.% or better,depending on the central value,and to sub-percent precision using reactor antineutrinos.A comparison of these two measurements from the same detector will help understand the current mild inconsistency between the value of Delta m^2.(2.)reported by solar neutrino experiments and the KamLAND experiment.

关键词： neutrino oscillation solar neutrino JUNO

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