阳泉市地下水水质评价及趋势预测

文中对阳泉市各类地下水尤其是岩溶地下水进行了水质现状评价、污染机理分析及趋势预测。     

泰安岩溶水水质演化规律分析

通过了解泰安市岩溶地区水文地质条件,根据多年的岩溶水化学组分含量,分析该地区的水质演化规律,分析得知,泰安市岩溶水在朝着恶化的方向发展。最后分析影响岩溶水水质的主要因素:岩溶水超量开采引起地下水动力场的改变和岩溶塌陷。同时,人类活动在时间和空间尺度上与岩溶水水质的变化亦有密切的关系。     

石河子蘑菇湖水库污染现状及治理

本文对新疆石河子蘑菇湖水库水质污染现状进行了调查和分析,阐述了水库水质污染主要原因.根据蘑菇湖水库周边区域经济社会发展趋势,结合水库水质污染现状,对蘑菇湖水库2020年水质污染情况进行预测.针对水库污染现状、 原因和趋势,提出相应污染防治措施和建议.     

娘子关泉岩溶地下水污染途径分析

对娘子关泉域内岩溶地下水的污染途径从点、线、面等方面进行了全面分析,对水质污染趋势和成因机理进行了合理解释,并就如何防治地下水污染提出了合理化建议,为娘子关泉域地下水污染防治和决策管理提供了科学依据。     

黄河循化至五佛寺河段水污染现状及预测

随着沿黄地区经济的发展和城镇人口的迅速增加，大量的工业废水和生活污水排水黄河，使黄河水质污染加重。在评价该河段水污染现状的基础上，对未来水污染趋势进行了预测，同时指出应当通过强化水环境管理，建立和完善有关政策法规，实行排污总量控制和排污许可制度等一系列对策措施，逐步改善黄河水质。     

马尔科夫链与GM(1,1)模型在岩溶地下水四氯化碳污染预测中的应用对比

为选择更优的岩溶地下水水质预测模型,以七里沟岩溶地下水源地四氯化碳污染区为研究区域,选用马尔科夫链与GM(1,1)模型分别对四氯化碳污染进行预测研究,并将预测值与实测值进行对比分析,探讨两种预测模型的适用性及差异性。结果表明:研究区四氯化碳污染监测数据具有一定的波动性,马尔科夫链模型预测结果拟合程度更好,GM(1,1)适用于具有一定变化趋势的水质监测数据。     

官厅水库水质趋势分析及对策研究

官厅水库水质污染曾经比较严重，于1997年退出了北京市饮用水水源体系。经过9年的综合治理．官厅水库水质有明显改善。通过采用PWQTrend水质污染趋势模型分析软件．对官厅水库库区近9年来的水质监测资料进行模拟计算，并对水质趋势进行分析研究，发现官厅水库库区有一部分项目明显好转．还有一部分项目有污染加重的趋势，进而提出官厅水库水污染控制及治理的对策和建议。     

山西神头泉流量的灰色预测模型研究

本文在研究岩溶水运动规律的基础上，应用灰色系统方法，建立了神头岩溶泉流量灰色动态预测模型，对其流量进行了预测，预测结果显示，从2001～2015年，神头泉流量总的趋势是下降状态，为此提出了神头泉域岩溶水资源开发利用和保护措施。     

万家寨引黄一期工程供水沿线水质分析与趋势预测

根据2005～2010年万家寨引黄一期工程沿线水质监测数据,对万家寨水库及汾河水库水质演变及现状进行评价分析,并采用PWQTrend水质污染趋势模型分析软件,对引黄沿线水质趋势进行预测。     

天津市浅层地下水（包括Ⅱ组水）水质污染浅析

了解地下水水质状况及污染趋势，对合理开发，利用地下水资源是非常必要的。文章根据１９９７－１９９９年地下水水质监测资料，对天津市支地下水天然状况，水质污染现状，污染成因及污染趋势进行了分析。     

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。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

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.