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1.
河流污染带的随机模拟方法   总被引:10,自引:0,他引:10  
黄平  陈铣成 《水文》1995,(3):8-12
根据随机理论,推导了一个描述污染带变化的概率模型,并采用Monte-Carlo抽样法对其求数值解。该随机模型的解是一个随机物,实例计算表明,它的解能够反映任一计算点的浓度变化趋势及范围,并能够给浓度等值线附加上概率的意义,表现了在不确定因素的影响下,污染带随机变化的情况。  相似文献
2.
运用简易、快捷、灵敏的ICP-MS法直接测定稀有多金属矿以及河水样品中的铀钍含量,并推算其与比放射性活度之间的定量关系,客观评价了某稀有多金属矿废水中的放射性水平以及额尔齐斯河流域的放射性污染现状。研究表明,某稀有多金属选矿废水铀含量可达78.311μg/L,钍含量达0.627μg/L。额尔齐斯河流域各支流河水铀、钍平均含量分别为0.584μg/L、0.025μg/L,其干流河水钍平均含量为0.019μg/L,而铀平均含量达2.234μg/L,远高于世界河水铀平均含量0.309μg/L。  相似文献
3.
傍河地下水水源地污染模式研究   总被引:5,自引:2,他引:3       下载免费PDF全文
李铎  宋雪琳  张燕君 《地球学报》2000,21(2):202-206
傍河取水是常见的地下水供水形式之一,但水源地的水质常常受到河流污染物的威胁。近年来,随着区域地下水位的下降和开采条件的变化,河水补给地下水的形式也趋于多样化,从而影响着污染物的迁移。本文通过对河水与地下水的各种关系的分析,给出了河水污染地下水的各种模式,并综合得出其数学模型及其解,最后用实例说明其应用过程。  相似文献
4.
弹性填料处理河道污水实验研究   总被引:1,自引:0,他引:1  
采用弹性填料曝气生物膜法对污染的河道水体进行处理的实验研究,结果表明,在2m/h的流速、水温为16℃~18℃、气水比为1∶1的条件下,采用弹性填料的生物膜处理系统运转正常,不易发生堵塞或系统短流,系统此时的水力停留时间为3.5h左右,污水中的COD和NH3-N去除率稳定,其均值分别为49.4%和19.1%。  相似文献
5.
河流生态修复技术研究概述   总被引:1,自引:0,他引:1  
李晋 《地下水》2011,(6):60-62
河流在人类社会发展中扮演着重要的角色,但由于人类的过度使用以及随意将污染物排放入河流中,造成河流的生态破坏、水体污染。对于河流的治理,国外已从传统的"污水处理、达标排放"治理目标转变为以水质再生为核心的"水的循环再利用",由单纯的"污染控制"技术发展为"水生态的修复与恢复"。本文介绍了河流生态修复的理念及其修复技术。  相似文献
6.
“井水不犯河水”水文地质学含义初步探讨   总被引:1,自引:0,他引:1  
利用水化学及同位素水文地质学的方法,对密云水库、潮白河及位于潮白河边的2个地下水分层专门监测井进行取样测试,并结合收集相关资料,从水位、水质及氚、氘、氧-18等同位素方面进行分析研究,对中国古语"井水不犯河水"的水文地质学方面的含义进行了一定的微观层次的分析探讨。得出研究点处潮白河水对50 m外的25 m深的浅井井水有一定的影响,而对67 m深井的影响很小,渗透作用分别滞后约20年和50年。另外三处实例也表现出了这一特点。认为产生这种现象的主要原因是由于粘土类地层的阻水作用以及地层沉积过程中的压实作用,尤其是差异性压实作用会使得水交替非常缓慢。  相似文献
7.
The Abrud–Arieş river system, western Romania, is subject to ongoing mining activity associated with Cu, Pb and Zn ore extraction. The catchment contains what is believed to be Europe's largest unutilized Au deposit at Roşia Montană that is planned to be exploited by open-cast mining techniques. The magnitude and environmental significance of metal (Cd, Cu, Pb, and Zn) concentrations in surface water and river channel sediment have been investigated along a 140 km reach of the Rivers Abrud and Arieş and 9 tributaries affected by mining. The speciation of sediment-bound metals was established using a 4-stage sequential extraction procedure (SEP) that identified four chemical phases: (1) exchangeable, (2) Fe/Mn oxides, (3) organic matter/sulphides and (4) residual. Peak solute and sediment-bound metal concentrations were found to occur in the River Abrud downstream of the EM Bucium mine and in mining-affected tributaries, with up to 71% of sites containing sediment metal concentrations in excess of Dutch intervention values. The River Arieş was found to be much less polluted than the River Abrud, with only Cu showing concentrations above guideline values, as a consequence of porphyry Cu mineralization in the catchment. The magnitude and spatial extent of metal pollution is influenced by local physico-chemical conditions and hydrological linkages between mining and local river systems. Sediment-bound Cd and Zn were found to be predominantly associated with the exchangeable phase of the sediment (9–74% and 6–65%, respectively), whilst Fe/Mn oxides (5–76%) and organic matter/sulphides (1–45%) generally accounted for a majority of Pb and Cu partitioning, respectively. Sites of environmentally significant sediment-metal pollution were identified in the Rivers Abrud and Arieş where exchangeable metal concentrations exceeded Dutch intervention values. The implications of metal contamination in the Arieş river basin to the proposed mining development at Roşia Montana are discussed in relation to other contaminated Romanian catchments and with the EU Water Framework Directive.  相似文献
8.
赵忠海 《城市地质》2001,13(4):36-42
本文在1/5万区域地质调查及顺义区国土资源与生态环境大调查的基础上,对顺义区内主要河流的污染情况进行了初步的调查与评价,并对其污染治理工作提出了几点建议。  相似文献
9.
Uranium and Th are important radioactive elements. Most studies were focused on their environmental impact from uranium deposits and mining sites. But other sorts of mines such as rare metals mines are associated highly with uranium and thorium, too. In China, the Irtysh River is the only river that runs into the Arctic Ocean. The famous Koktokay rare metal pegmatite deposit is located in the headwater region of this river and has been exploited for several decades. The waste ore piled along the riverside as long as several kilometers. The wastewater flom the concentrating plant is discharged into the river directly. In addition, uranium and thorium can be leached from the waste ore into the river in the weathering process. So it is necessary to study the uranium and thorium distribution in the branch and trunk streams of the Irtysh River and the wastewater from the mining site impact on it. In this study, the contents of uranium and thorium in water samples from the Irtysh River and rare metal mine wastewater have been detected directly with ICP-MS. Uranium and thorium distribution and geochemical behaviors in the Irtysh River basin have been studied. The environmental uranium and thorium pollution status in the Irtysh River and wastewater from a rare metal mine impact on it have also been evaluated. The study shows that uranium and thorium contents in wastewater from a rare metal mine are as high as 78.311 μg/L and 0.627 μg/L, respectively, so we should also pay attention to the radioactive pollution from the rare metal mine. The average contents of U and Th in the branch streams of the Irtysh River are 0.572 μg/L and 0.015 μg/L, respectively. At the mean time, in the trunk of the Irtysh River, average thorium content is 0.019 μg/L while U is up to 2.234 μg/L, much higher than the average content (0.0309 μg/L) of the world rivers. From upstream to downstream in the trunk of the Irtysh River, thorium content declines gradually due to dilution by other branches and deposition itself.  相似文献
10.
The study of hydrogeochemical data sets frequently calls for statistical dimension reducing techniques. It is well known that hydrochemical parameters are compositions and, for this type of data, the direct application of classical statistical methods based on the correlation matrix yield spurious results. But new results on compositional data analysis have identified the sampling space, the simplex, with an Euclidean space, a fact that allows us to define a simplicial factor analysis strategy, thus overcoming the problem. For illustration, we use samples from the Llobregat River and its tributaries (NE Spain). Three unobservable or latent factorial components are extracted, which are identified with pristine waters, potash-mining influence and urban sewage influence. These three factorial components or compositional factors are plotted in a factorial ternary diagram, which reflects the relative influence of each one of these factors on each observation.  相似文献
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