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31.
Modifications in the computed climatic water budget have made it possible to achieve good agreement between computed and measured stream flow on both a monthly and annual basis in basins without appreciable winter snow cover. Comparisons of computed and measured stream flow in 28 basins on the Delmarva peninsula show that for some basins the agreement is excellent (regression line essentially equals unity), for other basins the regression line has a slope of one but it is displaced above or below the y=x line, while for other basins, the slope of the regression line differs appreciably from unity. Study of the basins where agreement between computed and measured values is only fair to poor reveals that the patterns of disagreement can be used to provide information on the water holding capacity in the root zone of the soil, on the quantity of deep aquifer recharge within the basin, or on the effect of human modifications within the basin. The technique should also reveal the quantity of interbasin transfers or other consumptive uses within the basin. The water budget, thus, becomes a useful tool to study hydrologic characteristics or their changes over time within a basin.  相似文献   
32.
黑曲霉对弱酸性艳兰RAWL的吸附动力学和热力学研究   总被引:3,自引:0,他引:3  
借助吸附等温线比较了不同pH以及完整细胞与单细胞壁染料生物的吸附性能差异,化学修饰研究了菌体表面不同官能团对染料吸附的贡献,考察了不同温度下染料生物的吸附动力学,并进行了模型拟合.结果表明,黑曲霉的染料吸附较好地符合Freundlich方程( R2 >0.99),低pH值有利于染料吸附;染料吸附不仅发生在细胞壁,细胞内部也可发生;表面氨基作为主要的吸附官能团,其质子化导致的菌体正电荷和染料负离子间的静电引力作用是染料吸附的重要机理;吸附动力学可用拟二级速率方程描述( R2 =0.999 9);吸附活化能 Ea=5.21 kJ/mol,表明吸附具一定的活化性.  相似文献   
33.
“项目教学法”是一种以学生为中心的新型教学模式,在高职教育中应用广泛。从项目选取、项目实施、项目总结与评价以及考核方案设计等方面出发,结合教育实践,探讨了项目教学法在高职《环境监测》课程实践教学环节的应用,并对其实施效果进行了简要分析和总结。  相似文献   
34.
The integrated use of remotely sensed data and GIS to monitor a rapid recent delta formation was undertaken in the Tacarigua Lagoon, a mangrove coastal protected wetland in the north-central coast of Venezuela. Recently, the resource value of coastal wetlands such as coastal lagoons and deltas, has brought about a need to protect and conserve these ecosystems. To that end, valuable resources such as these should be continuously monitored so that temporal changes in their environment can be analysed. The importance of determining the cause, extent, and spatial distribution of these changes can then be used in different aspects of environmental studies, land suitability analyses and for wise resource management. Aerospace data interpretation and a field survey were utilised to study the formation of the Guapo River delta within the Tacarigua Lagoon and to map the expansion that this depositional environment has undergone. A historical set of aerial photographs and a radar image, together with a GIS, were used to assess the growth of the delta from the beginning of its formation up to the present time.  相似文献   
35.
张君杰 《环境科学与管理》2009,34(8):120-121,155
电厂烟气脱硫技术方法很多,常规燃煤脱硫方法通常分为三种,方法的选择主要取决于锅炉容量、燃烧设备类型、燃料种类、脱硫效率等,同时还须考虑电厂地理位置、副产品的利用等因素。本文介绍了循环流化床锅炉脱硫技术、湿式石灰石-石膏法烟气脱硫技术、生石灰-半干法烟气脱硫技术、氨肥法脱硫技术、电子束烟气脱硫技术、NOXSO同时脱硫脱硝技术、SNOXOM脱硫脱硝技术等,分析各种脱硫技术的应用范围、脱硫效率和优缺点等,为火电厂选择燃煤烟气脱硫措施提供了参考依据。  相似文献   
36.
在落地油污染区,采用曝气法进行了地质环境污染治理。通过曝气前后采样土壤样品、测试结果的分析与对比,研究了不同深度的地下水和土壤中石油类,以及Pb、Cd、Cr、As、Hg等"五毒"元素的污染组分变化,发现曝气法对于土壤石油类污染具有良好的治理效果。  相似文献   
37.
晏明生 《能源环境保护》2010,24(6):31-34,38
通过与目前火电厂应用最广泛的脱硫方法石灰石/石膏法比较,提出了湿式氨法脱硫工艺在成本投入低、环境污染小及社会经济效益好三方面的潜在优势.并分析了该法在我国火电厂烟气脱硫领域的应用前景。  相似文献   
38.
This paper presents an agile participatory urban soundscape planning process model, which is proposed as a prerequisite on which to build and reference the efficacy of urban soundscape planning. The model was developed through data synthesis and analysis and mapping engagement with diverse stakeholders across four applied soundscape projects in Brighton and Hove, UK. To the best of the authors’ knowledge, the model is the first of its kind in applied soundscape practice. The data was collected through semi-structured interviews with key stakeholders and document analysis of published resources. The framework used for the analysis of the findings comprised four core urban planning stages: goals and objectives, engagement (e.g. prediction/modelling/design/planning), implications, evaluation. The study found that when integrating soundscape planning with core urban planning stages it was necessary to first identify the appropriate stakeholders in relation to the project context. It was found that these stakeholders could be wide-ranging and unexpected, thereby reinforcing the appropriateness of incorporating an agile approach in the resulting model. The study also found that users’ perceptions are central to soundscape practice and need to be considered at each stage of a planning process to produce an effective and sustainable outcome. A variety of specific events, appropriate to the requirements of the stakeholders, are important for engaging planning authorities, users and other stakeholders at different stages. This study also demonstrated that an evidence-based evaluation method is recommended in an agile participatory urban soundscape planning process to assess stakeholders’ engagement at each stage and to inform and guide subsequent steps in the planning process relevant to the local context(s).  相似文献   
39.
饱和-非饱和介质热-水-应力耦合二维有限元分析   总被引:8,自引:0,他引:8  
从建立应力平衡方程、水连续性方程、能量守恒方程和弹塑性矩阵开始,使用Galerkin方法,将各控制方程分别在空间域和时间域进行离散,初步开发出了一个用于分析饱和-非饱和介质热-水-应力耦合弹塑性问题的二维有限元程序.通过对一个假定的核废料地下处置的热-水-应力耦合问题进行数值计算,在定性上验证了本程序的正确性.  相似文献   
40.
采用马来酸酐和丙烯酸为单体 ,用过硫酸钠和亚硫酸氢钠为引发剂 ,采用水溶液聚合法合成了用于替代三聚磷酸钠 (STPP)的助洗剂VS,并在不同洗衣粉中进行应用实验  相似文献   
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