基于DRWMLPE模型的岩溶潜水污染风险评价

选取中国北方某一典型岩溶潜水水源地为例,利用DRWM模型和DRWMLPE模型分别对其地下水本质脆弱性和地下水污染风险进行了评价.评价结果表明,研究区内地下水异常现象的发生与地下水本质脆弱性没有明显的相关性,而与地下水污染风险性具有较好的相关性,进而阐明了地下水本质脆弱性、污染负荷与污染风险之间的复杂关系.单参数敏感性分析结果验证了DRWMLPE评价模型的合理性并获知包气带介质是水源地地下水污染风险评价中最敏感的因素.DRWMLPE评价模型可推广到其他岩溶地下水污染风险评价,为地下水资源的可持续合理开发利用提供科学依据.     

贵阳市乌当区地下水脆弱性评价——基于AHP的改进DRASTIC模型

为了防止地下水在人类生产生活过程中受到污染,实现地下水资源合理利用及可持续发展,采用地下水脆弱性评价模型(DRASTIC模型),运用层次分析法(AHP)确定相应指标权重,以地理信息系统(MAPGIS软件)为平台,评价了贵阳市乌当区地下水脆弱性程度。通过MAPGIS软件做出贵阳市乌当区地下水脆弱性程度分区图,最后对贵阳市乌当区地下水的污染风险进行预测并提出了相应的对策。     

傍河区域地下水脆弱性研究——以第二松花江流域为例

 地下水脆弱性研究是合理开发利用和保护地下水的基础,它一直是国际水文地质研究的热点问题之一。以第二松花江流域地下水为研究对象,分别采用DRASTIC 方法和GOD 方法对地下水环境脆弱性进行评价,并利用实测铬含量对评价结果进行验证对比。研究结果表明:DRASTIC 模型对第二松花江流域地下水环境脆弱性的评价较为合适,评价结果更能真实地反映研究区地下水脆弱情况;第二松花江流域傍河区域的地下水环境较为脆弱,容易受到污染,故在布设水源地开采井时应尽量避开地下水高脆弱区,做到合理有效地开发利用地下水资源。     

寨底地下河系统脆弱性评价指标体系及方法

以研究岩溶地区地下水脆弱性评价指标体系、评价方法,为地下水资源保护提供对策为目的,本文以桂林寨底一海洋典型岩溶地下河系统为研究对象,针对西南岩溶区大气降水入渗的特点,选取覆盖层、地形坡度、地貌类型、地层岩性、地质构造、地下水水位埋深、降水量、人类活动8个指标,建立地下水脆弱性评价指标体系;结合地下水质量评价中的加附注评分法,突出地貌类型、地质构造作用的影响力;采用综合指数法,综合考虑各因子的权重,分别对系统内的地下水脆弱性进行评价,并根据系统内水井降雨后COD浓度的变化情况,对2种方法的地下水脆弱性评价结果进行验证评估。评价结果显示,区内地下水极度脆弱区主要分布在人类集中居住的岩溶谷地和洼地中。     

淮河流域平原区浅层地下水硝酸盐特殊脆弱性评价

特殊脆弱性评价是地下水硝酸盐污染区域性防治的前提.结合淮河流域水文地质条件和硝酸盐污染特点,对传统地下水特殊脆弱性模型DRASTIC进行了改进,建立了基于地下水位埋深(D)、净补给量(R)、含水层富水性(A)、土壤介质(S)、包气带介质(I)、土地利用类型(L)、地下水开采量(E)为评价因子的DRASILE模型,采用经验值与实际硝酸盐浓度共同确定体系给分表,利用二层次的层次分析法确定各指标的权重,最终制定了淮河流域平原区浅层地下水硝酸盐特殊脆弱性评价图.为了检验结果的可靠性,在SPSS21.0用F统计量和皮尔森相关系数(ρ)分别进行指标选取和脆弱性分值准确性的检验,最终通过显著性检验且相关系数达到0.559.本研究为地下水特殊脆弱性评价提供了新思路.     

基于GIS的广西岩溶生态环境脆弱性评价

以广西岩溶区为例,从导致岩溶生态环境脆弱性的本质因素入手,建立了岩溶生态环境脆弱性评价模型．选取碳酸盐岩分布面积百分比、地形坡度、地貌类型、土壤侵蚀强度、石漠化面积百分比、森林和灌丛覆盖率、早涝片面积作为评价因子,利用层次分析法确定评价因子的权重,并以ArcGis 8 Desktop为平台,利用软件的空间分析功能,通过模型的空间关系识别,进行了广西岩溶生态区脆弱性评价．     

竹鹅溪片区岩溶地下水污染特征及成因分析

针对岩溶区地下水易受到污染的情况,以柳州市竹鹅溪片区为研究对象,研究岩溶地下水污染特征。在对竹鹅溪片区的5个地下水监测点先后进行6次取样检测,检测的26项指标中污染比较严重的水质指标有总硬度、挥发性酚类、硝酸盐、氨氮、镉和总大肠杆菌群,其余20项指标检测含量都在《地下水质量标准》(GBT14848-93)的Ⅱ类水标准限值内。依据检测结果对地下水的水质现状进行评价,并且结合竹鹅溪片区的水文地质条件、污染源现状调查情况、地表水检测结果等分析了地下水水质指标中超标及污染严重的成因,对研究该片区地下水污染防护措施具有一定的应用价值。     

采煤矿区地下水脆弱性评价

地下水脆弱性主要是由含水层中的环境地球化学效应和包气带土壤结构效应共同作用的结果。结合采煤矿区地下水污染的实际情况,分析了地下水脆弱性的影响因素,采用数学模型和 DRASIC 评价指标体系法对矿区地下水脆弱性进行初步研究。给出了相应评价因子,建立了采煤矿区地下水水环境脆弱性评价指标体系,定量化评价地下水潜在的易污染程度,为采煤矿区的资源开采、水环境保护和地下水资源管理提供科学依据。     

采煤矿区地下水脆弱性评价

地下水脆弱性主要是由含水层中的环境地球化学效应和包气带土壤结构效应共同作用的结果。结合采煤矿区地下水污染的实际情况，分析了地下水脆弱性的影响因素，采用数学模型和DRASIC评价指标体系法对矿区地下水脆弱性进行初步研究。给出了相应评价因子，建立了采煤矿区地下水水环境脆弱性评价指标体系，定量化评价地下水潜在的易污染程度，为采煤矿区的资源开采、水环境保护和地下水资源管理提供科学依据。     

灌江流域岩溶环境与石漠化

石漠化是岩溶地区脆弱的岩溶地质基础上形成的一种荒漠化现象,它的产生与岩溶环境条件直接相关。通过对流域内的岩性、地貌、岩溶形态、表层岩溶带、地下管道在岩溶水系统中构成的水文网络及动态变化等岩溶环境特征的调查研究,论述了不同环境条件下,对生态环境影响程度及其产生的后果。根据石漠化的分布现状与岩溶环境特征之间的关系,分析石漠化的发展趋势。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that