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1.
三江源地区是长江、黄河、澜沧江三大河流的发源地,其生态环境质量的好坏直接关系到中下游地区的可持续发展及生态安全.本文以直根尕卡地区为研究对象,从可持续发展的观点出发,在1:25万区域环境地质调查的基础上,综合分析了该区水资源、土壤资源及生物资源状况,揭示了该区生态环境存在的3个问题,提出了三江源地区可持续发展的几点建议及对策.  相似文献   

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Artificial freezing of ground by refrigerating machines requires considerable power and expense, so it is comparatively seldom applied and almost always for a short period. In the regions of severe climate, seasonal freezing and long-term preservation of low temperatures in a mass of frozen ground can compete in effectiveness and economy with the traditional methods of loose ground stabilization, quicksand and boggy—clayey deposits, in particular. In practice, different methods and systems are applied for freezing the ground using the cold atmosphere air as a heat-absorbing medium. Systems with forced pumping of the intermediate heat carrier or of the air itself are more economic than machine freezing, but they are unreliable and maintenance is very expensive.

Freezing devices using natural circulation of a single-phase and double-phase heat carrier in hermetically sealed cavities or thermosiphons permit effective control of the temperature regime of the ground in the seasonal and annual cycles of temperature variation of the ground and atmosphere air with the minimum operating expense.

The paper considers the operational features of freezing systems and different devices, and gives examples of the utilization of artificially frozen ground in hydraulic structures and in foundations of industrial buildings and dwelling houses. The possibility of creating artificially frozen masses used as foundations of the structures built in severe climatic regions is considered, and examples of the existing buildings constructed on the artificial lenses of frozen ground are given.  相似文献   


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The paper presents chemical and structural analysis of geopolymer materials which are obtained by alkali-activated calcined clay (metakaolin) originated from Serbia under strictly defined conditions. Characterization of the metakaolin and geopolymers molecular structure has been done using X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The paper presents the possibility of obtaining geopolymer structure and differences in chemical and structural characterization of these materials taking into account the concentration of NaOH as a variable parameter. The results of MALDI analysis of metakaolin and synthesized geopolymer structures using various matrix system: 2,4,6 trihydroxyacetophenone (THAP), α-cyano-4-hydroxycinnamic, 2,6 dihydroxyacetophenone and laser desorption/ionization, have shown that THAP matrix is the most appropriate for analysing these aluminosilicate materials.  相似文献   

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面向可持续发展的冰冻圈科学   总被引:1,自引:6,他引:1  
21世纪以来, 在全球气候变暖的大背景下, 冰冻圈科学发展快速。在梳理国际冰冻圈相关研究态势、 分析中国相关研究动向的基础上, 总结了“冰冻圈科学”发展的历程并简要介绍了冰冻圈科学的基本框架。研究指出, 自20世纪70年代冰冻圈概念正式提出以来, 国际社会以推出气候与冰冻圈(WCRP-CliC)计划和成立国际冰冻圈科学协会(IACS)为标志, 并在深化冰冻圈自身机理、 过程认识的同时, 更加关注与其他圈层之间相互作用中的冰冻圈效应, 表明冰冻圈研究趋向变化 - 影响 - 适应这一主线发展, 在一定程度显现出了“冰冻圈科学”的核心特征。中国冰冻圈研究近20年、 尤其是近10年发展迅猛, 沿着冰冻圈科学的主体思路, 在冰冻圈变化, 冰冻圈变化对生态、 水文、 气候、 地表环境以及社会经济的影响等方面取得了系统性成果, 对冰冻圈科学的内涵和外延有了系统的认识。在分析国际冰冻圈科学孕育和发展背景并简要总结中国冰冻圈研究近况基础上, 对冰冻圈科学学科框架体系从科学内涵和外延、 研究构架和学科组成等方面进行了论述, 冰冻圈科学已经成为一门涉及广泛、 过程机理研究与可持续发展密切关联的全新学科。  相似文献   

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本文以偏高岭土基地质聚合物(SiO_2/Al_2O_3=3.2)为基体,通过水热合成法将其原位转化成P型沸石分子筛。研究水热温度、NaOH浓度及水热时间对P型沸石分子筛的结晶程度及形貌的影响,得到偏高岭土基地质聚合物原位合成P型沸石分子筛的适宜条件为:水热温度100℃,NaOH浓度2.0 mol/L,水热时间24 h。该法工艺简单,环境友好,可控成型。在此方法的基础上通过改变原材料和反应条件,可以合成其他类型的沸石分子筛。  相似文献   

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区域水资源可持续利用的综合评价方法   总被引:8,自引:4,他引:8       下载免费PDF全文
水资源可持续利用指标体系及评价方法是水资源可持续利用研究的核心问题之一。以复合系统理论为基础,将水资源、社会经济和环境组成的复合系统定义为水资源可持续利用系统(RSWRS系统)。应用Bossel可持续发展基本定向指标框架,建立了水资源可持续利用指标评价体系。应用系统综合评价法,权重采用基于Bossel评分标准,以参考状态的离差平方和最大法计算,建立了以RSWRS系统发展综合指数和发展态势度量模型。以陕西省为例,进行了水资源可持续利用的综合定量评价。  相似文献   

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Water scarcity is a becoming a critical issue globally, driven largely by the demands of an exponentially growing human population and complicated by the impacts of climate change on the amounts and distribution of precipitation. It is also due to mismanagement as scarce water resources are being used simultaneously for irrigation, power generation, public and industrial water supply, flood reduction, and wastewater disposal without consideration of the cumulative impacts to the water resources themselves. This paper outlines eight ecologically based principles and associated guidelines as the basis for integrated and watershed-based management of the world’s water resources.  相似文献   

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区域水资源可持续利用评价指标体系的建立   总被引:87,自引:4,他引:87       下载免费PDF全文
立足于区域(或流域)水资源的特点,考虑到区域(或流域)内社会经济发展对水的依赖程度,以及社会经济发展水平的不平衡和科技水平的差异,借鉴国际可持续发展标准和国内其它资源可持续发展的认知水平,遵循科学、实用及简明的原则,构建水资源可持续发展评价指标体系,探索性地提出了水资源可持续发展能力的五级划分标准.  相似文献   

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天然气成因类型及判别标志   总被引:27,自引:2,他引:27  
刘文汇  徐永昌 《沉积学报》1996,14(1):110-116
本文通过前人对天然气类型划分的分析,基于多年的研究结果,以“多源复合、多阶连续”的天然气成因新模式,提出了科学的天然成因类型划分方案,并讨论了不同成因类型天然气的地球化学特征,建立了天然气成因类型的判识标志。  相似文献   

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徐明 《水科学进展》2004,15(5):655-659
公元前256年建立的四川都江堰水利枢纽工程是世界历史上至今仍在发挥巨大作用的最古老的水利工程之一.但是随着工程基础设施的老化,生态环境的恶化,周边地区工农业的过度开发,原有的传统水利发展模式已经不能适应都江堰灌区当前和未来的发展需求.因此,提出了一个以可持续发展思想为指导的、有明确发展目标、有总体发展构架的、又能对其进行实施评估的都江堰水利发展战略框架以及与之相适应的实施对策.用以推动都江堰灌区水利可持续发展的进程.  相似文献   

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“化学定时炸弹”与可持续发展   总被引:20,自引:2,他引:20  
“化学定时炸弹”是指自然界中由于化学物质的释放或活化而导致的延缓的有害效应。其一旦发生危害极大,小则影响局部流域,大则影响整个区域,甚至整个国家。我国属发展中国家,经济正处于快速发展阶段,短期内不可避免地向自然界投放有害及化学物质。因此,我国应尽早制定长远的政策,在对我国的陆地进行持续观测的同时,深入研究我国“化学定时炸弹”的基本问题,发展对解决“化学定时炸弹”极具潜力的“地球化学工程学”方法,有效地防治“化学定时炸弹”灾害的发生,以保障我国经济与环境的可持续发展。  相似文献   

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矿山可持续发展综合物探技术方法研究   总被引:3,自引:2,他引:3  
论述矿山可持续发展综合物探技术研究和推广应用的必要性、应用领域及主要技术特点 ,介绍了新的数据处理方法即非线性地球物理联合反演方法。通过实例说明该技术具有投资少、见效快等优点 ,有良好的应用前景。  相似文献   

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Hydrogeology and sustainable agriculture   总被引:3,自引:0,他引:3  
 The world's population continues to grow and to require more and more food. Attempts by modern high output agriculture to meet this need have led to serious environmental problems. A more sustainable balance is now required and is being sought in a variety of ways. Hydrogeologists should continue to highlight the threat posed by agriculture to groundwater, particularly since groundwater is a hidden resource and its degradation and rehabilitation often take place slowly. But the time has come for groundwater specialists to go further and become actively involved in helping to provide practical and sustainable solutions. The agriculture of the future requires a holistic approach which balances the essential economics of food production with equally valid environmental needs, including those of groundwater. Such an approach demands cross-sectoral collaboration involving multidisciplinary research and action within an integrated policy framework. This paper reviews the current groundwater/agriculture interface and some of the attempts being made to achieve a more truly sustainable agriculture with particular emphasis on European experience. It aims to stimulate greater interest and involvement by hydrogeologists in helping to bring about realistic solutions that will enable future generations to enjoy adequate good quality food and water. Received: 9 August 1996 / Accepted: 11 November 1996  相似文献   

19.
Susan Place 《GeoJournal》1995,35(2):161-173
Acknowledgements: The research for this article was made possible by a Fulbright-Hays Faculty Research Grant. Guy King, Beth Mills, Chuck Nelson, and D.J. O'Donnell kindly provided assistance with various phases of map production.  相似文献   

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地热能规模化利用的可持续开发,通常需要建立数学模型,以实现定量管理和预测。文章评述OpenGeoSys(OGS)数值模拟软件及其在地热资源开发利用过程中的应用算例。OGS是一款基于有限元的免费开源软件,它可处理与地热能开发相关的水流场-温度场-力学场-化学场等多场耦合过程。OGS已应用在国内外多个地热场地,文中着重介绍它在浅层地热能的流体温度变化预测、水热型地热能开发过程中的采灌井距优化、结垢机理和干热岩开发过程中的渗透性演化等方面的应用算例,为地热能的开发提供计算手段和参考。  相似文献   

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