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391.
本文对贵州省洪家渡电站K40溶洞封堵处理设计与施工进行了分析,并提出了岩溶地区复杂地质条件的处理方法。即在查清地质条件的基础上,采用分区处理,多种工程手段相结合的措施。 相似文献
392.
区域开发是当前普遍采用的一种经济发展模式,然而区域开发活动引起的灾害还没有引起足够的重视。该文多区域开发建设活动与区域环境相互影响的观点,介绍了对区域开发引起的灾害进行识别的方法及其对策分析。区域灾害识别可采用历史记录法,成因分析法、预测法等方法。区域灾害对策有非工程性和工程性两类,工程性对策应根据区域灾害的类型、频率、强度、损失及区域开发性质来决定,而非工程性对策中建立区域统一的防灾救灾组织管理 相似文献
393.
经济手段对环境保护的作用王奇,李庆伦(沈阳市环境保护投资公司沈阳110003)(东北大学表面所)IMPROVINGTHETREATMENTEFFCTOFWASTEWATERCONTAININGLEADANDACIDBYSCIENTIFICMANAGE... 相似文献
394.
区域开发生态影响评价方法及应用 总被引:7,自引:0,他引:7
建立一套系统的区域生态影响评价方法,对于区域环评和环境的可持续发展具有重要的意义。以济南舜湖社区区域开发为例,建立和应用由生态指标法、图形叠图法、景观生态学方法构成的方法体系,对舜湖社区区域开发生态环境影响进行了评价,并提出生态保护和建设的具体措施。结果表明,3者构成的方法体系,能较全面的反映生态环境质量现状,预测生态环境影响,有较为广泛的应用前景。 相似文献
395.
During numerical simulation of air flow in the vadose zone, it was noticed that a small sinusoidal pressure would cause a gradual one-way migration of the pore gas. This was found to be a physical phenomenon, not a numerical artifact of the finite element simulation. The one-way migration occurs because the atmospheric pressure, and hence the air density, is slightly greater when air is flowing into the ground than when air is flowing out of the ground. A simple analytic theory of the phenomenon is presented, together with analytic calculations using actual barometric pressure data. In soil of one Darcy permeability, the one-way migration is of the order of a few tenths of a meter per year for either plane flow from ground surface or for radial flow from an open borehole. The migration is sufficiently small that it will have no practical consequences in most circumstances; however, investigators who conduct detailed numerical modeling should recognize that this phenomenon is not a numerical artifact in an apparently linear system. 相似文献
396.
GIS技术在城区大气降尘污染分区评价中的应用 总被引:13,自引:0,他引:13
应用地理信息系统(GIS)技术分析了焦作市城区大气降尘污染状况。根据1995年城区降尘实测数据,绘制了降尘量等值线图,分析了城区降尘污染持的空间分布特征,引入降尘污染指数,将降尘污染程度做了六级划分,并利用ARC/INFO软件进行图像处理,生成拓扑关系,从而对焦作城区降尘污染程度进行了分区和评价。 相似文献
397.
Chein-Jung Shiu Shaw Chen Liu Chih-Chung Chang Jen-Ping Chen Charles C.K. Chou Chuan-Yao Lin Chea-Yuan Young 《Atmospheric environment (Oxford, England : 1994)》2007,41(40):9324-9340
An observation-based method (OBM) is developed to evaluate the ozone (O3) production efficiency (O3 molecules produced per NOx molecule consumed) and O3 production rate (P(O3)) during a field campaign in southern Taiwan. The method can also provide an estimate of the concentration of OH. A key step in the method is to use observed concentrations of two aromatic hydrocarbons, namely ethylbenzene and m,p-xylene, to estimate the degree of photochemical processing and amounts of photochemically consumed NOx and NMHCs by OH. In addition, total oxidant (O3+NO2) instead of O3 itself turns out to be very useful for representing ozone production in the OBM approach. The average O3 production efficiency during the field campaign in Fall (2003) is found to be about 10.2±3.9. The relationship of P(O3) with NOx is examined and compared with a one-dimensional (1D) photochemical model. Values of P(O3) derived from the OBM are slightly lower than those calculated in the 1D model. However, OH concentrations estimated by the OBM are about a factor of 2 lower than the 1D model. Fresh emissions, which affect the degree of photochemical processing appear to be a major cause of the underestimate. We have developed a three-dimensional (3D) OBM O3 production diagram that resembles the EKMA ozone isopleth diagram to study the relationship of the total oxidant versus O3 precursors. The 3D OBM O3 production diagram suggests that reducing emissions of NMHCs are more effective in controlling O3 than reducing NOx. However, significant uncertainties remain in the OBM, and considerable more work is required to minimize these uncertainties before a definitive control strategy can be reached. The observation-based approach provides a good alternative to measuring peroxy radicals for evaluating the production of O3 and formulating O3 control strategy in urban and suburban environments. 相似文献
398.
The EU directives on air quality force member states to inform the public on the status of the ambient air quality. The Internet is commonly used for this purpose and often air quality is being presented as an index ranging from good to bad. A review of existing websites and air quality indices shows that the way air quality is interpreted differs considerably. The paper presents a new air quality index. The index is part of a project to develop a website dedicated to comparing air quality in European cities. The common air quality index (CAQI) is not aimed at replacing existing local indices. The CAQI is a set of two indices: one for roadside monitoring sites and one for average city background conditions. Differentiating between roadside and general city conditions is a first step in assuring consistence in the parameters that are being compared. 相似文献
399.
铁岭市各类大气污染源浓度贡献分析 总被引:2,自引:0,他引:2
利用铁岭市2004年的PM10(可吸入颗粒物)和SO2(二氧化硫)大气环境监测资料、污染源排放清单资料和气象资料,以及AERMOD模型(1)进行了铁岭市大气环境质量区域评价。结果表明:铁岭市低架源对地面浓度的贡献较大,高架源对地面浓度的贡献相对较小。 相似文献
400.
分析了实施流域内环境资源区域补偿工作存在的主要问题,对制度的实施提出了初步的对策建议:要通过加强立法和制定标准使补偿制度规范化,通过实施公正的监测,建立协调机制和补偿资金测算、营运机制等措施,实现环境利益和经济利益的均衡. 相似文献