节水型社会建设的重点与难点

水资源短缺成为制约经济社会发展的"瓶颈"因素,建设节水型社会是实现水资源可持续利用与经济社会可持续发展的战略举措.通过探讨,明确了我国节水型社会建设的目的与任务,根据用水现状和节水潜力,以及我国国情和体制与机制,对节水型社会建设的重点进行了分析,指出了节水型社会建设的难点.     

海河流域节水型社会建设若干问题探讨

海河流域水资源短缺、水资源和水生态环境恶化已成为流域经济社会可持续发展的瓶颈,建设节水型社会是海河流域经济社会协调发展的必然要求,是解决流域水资源问题的战略举措.根据流域水资源状况,对"十一五"期间推进节水型社会建设所面临的问题进行分析,提出流域节水型社会建设构想.     

浅谈总量控制在建设节水型社会中的作用

我国北方干旱地区水资源短缺,严重制约了经济社会的发展,生态环境形势严峻;同时水资源利用效率及效益低下。因此,大力推行节水、建设节水型社会成为北方干旱地区可持续发展战略的重要保障。本文分析了聊城市水资源特点及用水现状,分析了需水总量在建设节水型社会中的作用和地位,提出了聊城市建设节水型社会的思路、目标和措施。     

浅谈总量控制在聊城市建设节水型社会中的作用

我国北方干旱地区水资源短缺,严重制约了经济社会的发展,生态环境形势严峻;同时水资源利用效率及效益低下,因此大力推行节水、建设节水型社会成为北方干旱地区可持续发展战略的重要保障。本文以山东省聊城市为代表,分析了该市水资源特点及用水现状,分析了需水总量控制在建设节水型社会中的作用和地位,提出了聊城市建设节水型社会的思路、目标和措施。     

宁夏节水型社会建设的思路与做法

宁夏回族自治区是水资源严重短缺的省区之一,人均水资源可利用量664 m3,水资源供需矛盾成为宁夏经济社会发展的重要制约因素。作为第一个省级全国节水型社会建设试点,近年,宁夏结合自身情况,确定节水型社会建设总体思路并积极推动,取得了显著成效和宝贵经验,为西北同类干旱地区节水型社会建设提供参考。     

长江流域节水型社会建设效果分析

长江流域水资源丰富,是我国水资源配置的战略水源地.加强长江流域节水型社会建设,对保证本流域及全国经济社会可持续发展均具有非常重要的意义.结合长江流域水情特点,分析了长江流域节水现状用水量和用水水平,预测了近期长江流域节水型社会建设效果.长江流域节水型社会建设试点工作的成功,对全国丰水地区节水型社会建设具有很好的示范作用.     

关于广东建设节水型社会的几点思考

广东自然水资源条件较优越,但人均水资源拥有量却低于全国平均水平,干旱缺水以及水污染导致的水质型缺水日趋严重.水资源问题已成为广东经济社会持续发展的制约因素.以科学发展观为指导思想,建设人水和谐的节水型社会,是广东应对水资源问题日趋严重情势的战略对策.在剖析广东省存在的主要水资源问题的基础上,阐述广东建设节水型社会的战略意义,并对广东建设节水型社会提出几点对策建议:节水与治污相结合,准确把握节水型社会建设的战略重点,着力培养社会节水意识,全面推动节水体制的建设,设立建设节水型社会的专门机构,加强节水技术的研究与开发.     

辽阳市节水型社会建设模式探究

辽阳市是我国北方缺水城市之一,水资源短缺、水污染严重和水生态恶化已经成为制约全市经济社会发展的主要＂瓶颈＂。文章在全面分析辽阳市气候特征、水资源条件及经济社会发展水平的基础上,重点剖析了辽阳市在节水型社会建设中面临的形势和存在的主要问题,并结合辽阳市实际,从法律、行政、经济、工程技术等方面,提出了该地区节水型社会建设模式和发展战略。     

建设节水型社会 保护敦煌生态环境和历史文化遗产

敦煌市位于甘肃省河西走廊最西端,是一个自然条件差、生态环境脆弱、水资源匮乏的城市,水资源供需矛盾和生态环境的渐趋恶化成为制约敦煌市经济社会可持续发展的瓶颈。加快节水型社会建设,实现水资源的优化配置,是敦煌市经济社会可持续发展的希望所在。通过对敦煌市节水型社会建设重要性和紧迫性的分析,总结了其主要做法、主要成效和经验。     

解决中国水资源短缺问题的根本出路——汪恕诚部长答学习时报记者问

6月23日,汪恕诚部长在中央党校作了《建设节水型社会,保障经济社会可持续发展》的报告。日前,记者就中国水资源短缺的严峻形势,节水型社会的本质特征和实现途径,我国节水型社会建设的目标任务和工作要求等问题,采访了汪恕诚。记者:您在中央党校的报告中主要谈了如何解决我国水资源短缺的问题。这个问题可以说由来已久,而且,随着人口的增加,经济的发展,愈显沉重。水资源问题关系到人类的生存和经济社会的可持续发展,决不可等闲视之。作为国家的水利部部长,您觉得有什么有效的应对之策?汪恕诚:我认为,建设节水型社会是解决我国水资源短缺问题…     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。