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ESTABLISHMENT AND THEORETICAL CALCULATING FRAMEWORK FOR BEIJING water PRICE SYSTEM

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Deterioration Mechanisms of Sulfate Attack on Concrete under Alternate Action

第4届流域管理和城市供水国际会议

作者： Peiling Yang~* Yunkai Li Tingwu Xu Shumei Ren water conservancy and civil engineering college china agricultural university Beijing 100083 china

＜正＞ Rational water price is the economic measure for improving optimal water resources allocation and *** the issue of water price system is a rather complicated problem that involves many disciplines and *** on the delineation of the easily confused current concepts of cost water price,theoretical water price,production water price,target water price,shadow water price,equilibrium water price,water resources cost,water resourcesprice and water resources fee in price theory,this paper analyzed the primary problems existing in the current Beijing waterprice system and proposed a 3-fold water price theory pattern（resources water price,engineering water price andenvironment water price）for sustainability-oriented development in Beijing and described the calculating method for the3-fold water prices in ***,the model is be used to conduct the cost water price accounting tor Hong Weiwaterworks in Hai Dian District,Beijing.

关键词： sustainable development water price price system Beijing

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 355-359页

作者：高润东 State Key Laboratory of Hydroscience and engineering Tsinghua University

By micro- and macro-observations, the deterioration mechanisms of concrete under alternate action between repeated sub-high temperature/cooling by water and sodium sulfate solution attack （TW-SA） were studied; meanwhile, the single sodium sulfate solution attack （SA） was also done as comparison. Micro-observations included the analysis of attack products by thermal analysis method and the determination of sulfate-ion content from surface to interior by chemical titrating method （modified barium sulfate gravimetric method）. Macro-observations mainly included the mechanical behaviors such as compressive strength, splitting strength. The experimental results indicate, in both cases, the main attack product is ettringite, only in the first layer of case SA some gypsum is checked; in case SA, the sulfate ions mainly concentrate in the surface layer, so the attack is relatively mild; but in case TW-SA, the repeated sub-high temperature/cooling by water promotes the sulfate ions diffusing inwards, which leads to obvious strength degradation.

关键词： concrete sulfate repeated sub-high temperature/cooling by water attack product sulfate-ion content strength

青铜峡与八盘峡水电站水中泥沙含量对空化压力的影响

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水力发电学报 2008年第4期27卷 44-47页

作者：王磊朱茹莎常近时中国农业大学水利与土木工程学院北京100083

本文对黄河上游青铜峡、八盘峡水电站引用水中含沙量对水空化压力特性的影响进行了专项研究;实测了不同浓度含沙水样的初生空化与临界空化压力值。实测结果表明,随着含沙量的增大,初生空化与临界空化压力值均有所提高,且接近线性关系。... 详细信息

本文对黄河上游青铜峡、八盘峡水电站引用水中含沙量对水空化压力特性的影响进行了专项研究;实测了不同浓度含沙水样的初生空化与临界空化压力值。实测结果表明,随着含沙量的增大,初生空化与临界空化压力值均有所提高,且接近线性关系。此成果为黄河上游的水电站水轮机和水泵站的水泵合理确定安装高程提供重要依据,以减少空蚀带来的经济损失。

关键词：水力学空蚀泥沙磨损初生空化压力临界空化压力青铜峡水电站八盘峡水电站

Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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Science china Earth Sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2, LIU Han1, PAN Yinghua3, ZHAO Jun2, ZHAO Shiwei2 & YANG Yonghui2 1. The Key Laboratory of Modern Precision Agriculture System Integration Research, college of Hydraulic and civil Engineer-ing, china agricultural university, Beijing 100083, china 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and water Conservation, Yangling 712100, china 3. Geographic and Resources Management college, Yantai Normal university, Yantai 264025, china The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling China Geographic and Resources Management college Yantai Normal University Yantai China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2 cases were conducted. Case Ⅰ was done under a rainfall intensity of 20 mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 20° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82%/1.39% and4.49%/3.529% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

Household Fuel Structure and Effect on Indoor Air Quality in Rural North Sichuan Province

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Household Fuel Structure and Effect on Indoor Air Quality in...

国际农业工程大会

作者： Junhua Xiao graduate Studentcollege of water conservancy and civil English china agricultural university Beijing 100083 chinaQuanyuan Wei graduate Studentcollege of water conservancy and civil English china agricultural university Beijing 100083 china.Renjie Dong Professor PhDcollege of water conservancy and civil English china agricultural university Beijing 100083 china.

＜正＞ To explore the relation between household fuel structure and indoors air quality in rural regions. The concentration of SO2 and CO in kitchens of 90 families randomly selected in 3 villages of north Sichuan Province were monitored during period from May 18 to June 9 in 2004, and the local basic situation and the use of fuel for cooking and heating were investigated by questionnaire in every selected family. The main fuels in these regions are

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水工模型试验中薄壁堰缩尺效应分析

山东农业大学学报（自然科学版） 2002年第4期33卷 499-502页

作者：王仲发山东农业大学水利土木工程学院山东泰安271018

缩尺效应是影响水工模型试验精度的重要因素之一。本文通过矩形薄壁堰试验 ,验证了缩尺效应的存在 ,分析了缩尺效应对矩形薄壁堰泄水能力的影响 ,推荐了计算精度较高的计算公式 ,提出了减小缩尺效应的措施及建议。

关键词：水工模型试验薄壁堰缩尺效应分析表面张力

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, Beijing 100101, china 2. Institute of Forestry, Chinese Academy of Forestry Sciences, Beijing 100091, china 3. Department of civil engineering, university of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, Chinese Academy of Sciences, Beijing 100085, china 5. college of Resources and Environment, Southwest agricultural university, Chongqing 400716, china Correspondence should be addressed to Chen Hao Key Laboratory of water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of civil engineering University of Hong Kong Hong Kong China Eco-environmental Research Center Chinese Academy of Sciences Beijing China college of Resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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水环境变化对中华鲟的影响

水电能源科学 2009年第3期27卷 35-37页

作者：胡小琴姜翠玲裴海峰谢向前河海大学水文水资源学院江苏南京210098 内蒙古农业大学水利与土木建筑工程学院内蒙古呼和浩特010018 中国水电顾问集团华东勘测设计院浙江杭州310014

针对中华鲟为国家一级保护动物,其独特的生物学特性对生存的水域环境要求较高的特点,通过对长江宜昌段水质监测,分析了产卵场水质及水利工程建设对中华鲟生殖、繁育产生的影响,对保护中华鲟物种资源具有十分重要的现实意义。

关键词：中华鲟水环境污染水利工程建设影响

Studies on Photosynthetic Rate of Sunflower and Its Influence Factors under Salt Stress

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Studies on Photosynthetic Rate of Sunflower and Its Influenc...