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281.
铁有机骨架材料的快速合成及对阴离子染料的吸附性能   总被引:5,自引:2,他引:3  
染料废水色度高,难以生化处理,吸附法是有色废水处理的重要方法.采用常温快速合成铁有机骨架材料,通过IR和XRD对合成的材料进行表征;并研究铁有机骨架材料对阴离子染料的吸附性能.结果表明常温快速反应能够合成铁有机骨架材料,材料比表面积和孔体积较高,等电点p H为3.7.铁有机骨架材料在酸性条件下更容易吸附水中的阴离子染料;随染料浓度的增加,材料对染料的吸附量逐渐增大,Langmuir恒温吸附模型可以很好描述该过程,计算的吸附参数表明吸附过程容易进行.材料对染料的吸附为准二级动力学,染料结构会显著影响铁骨架材料吸附过程,络合结构的偶氮染料能够快速达到吸附平衡.  相似文献   
282.
我国现有的环境卫生标准体系与环境保护目标相脱节、体系定位模糊、体系框架未体现专业化,且对流程管理和质量管理重视不足、体系结构不合理。所以重新设计中国环境卫生标准体系应遵循的原则包括以环境保护为最终目标、应用生命周期管理原则、区分强制性与推荐性标准、标准在体系框架内分布合理。据此设计了"专业—流程—质量"三维体系框架及各专业分体系。建议以新框架指导标准制(修)订;推进环境卫生法律法规与强制性标准统一管理,推荐性标准自愿执行;并实现标准查询和管理的信息化。  相似文献   
283.
本文在对西昆仑山广布的岩浆岩尤其是花岗岩研究取得的成果基础上 ,结合区域构造、沉积建造等其它地质特征 ,再造了西昆仑山地质构造发展历程 ,进而研究了区内成矿堆积环境及其矿床地质特征。结果表明 ,西昆仑山经历了复杂的地质构造演化 ,是一条由北而南分别由加里东造山带、华力西造山带和燕山早期造山带组成的复合型造山带。区内存在以下 5种主要成矿堆积环境 :洋脊 (蛇绿岩 )成矿堆积环境 (塞浦路斯型含铜黄铁矿矿床 ,豆荚状铬、镍矿床 ) ,被动陆缘成矿堆积环境 (MVT铅锌矿床 ,Sedex型铅铜矿床 ) ,火山弧成矿堆积环境 (斑岩型铜矿床 ,黑矿型铜锌铅矿床 ,矽卡岩型铜铅锌多金属矿床 ) ,弧后盆地成矿堆积环境 (海底火山喷发沉积型铁铜金矿床 ,气液充填型铜金铁矿床 )和同碰撞成矿堆积环境 (伟晶岩型稀有金属矿床 ,伟晶岩型多金属银矿床 )  相似文献   
284.
Indicator system and evaluation framework for sustainable development   总被引:2,自引:0,他引:2  
IntroductionThenotionofsustainabledevelopmentwasproposedintheWorldConservationStrategy(IUCN,1980).Itispointedoutthattheconservationandthesustainabledevelopmentaremutuallydependentandtheyshouldbeintegrated,wheretheconservationmeansthemanagementofhuman…  相似文献   
285.
由早中元古代中深变质岩系组成的华南加里东海盆基底及东海、南海古陆。元古代晚期,海盆在拉张环境下继续沉降,于震旦、寒武、奥陶纪期间,沉积了厚近两万米的地槽型火山-砂泥质建造,陆源碎屑主要来自东海、南海古陆,直到中生代晚期古陆才裂陷成海,始成今日的海陆分布格局。  相似文献   
286.
The European Union Water Framework Directive recognises the need for and value of biological monitoring. This paper reviews the modelling approach known as River Invertebrate Prediction and Classification System (RIVPACS for assessing the ecological quality of river sites using macroinvertebrate sampling. The RIVPACS philosophy is to develop statistical relationships between the fauna and the environmental characteristics of a large set of high quality reference sites which can be used to predict the macroinvertebrate fauna to be expected at any site in the absence of pollution or other environmental stress. The observed fauna at new test sites can then be compared with their site-specific expected fauna to derive indices of ecological quality. All methodological decisions in any such model development have implications for the reliability, precision and robustness of any resulting indices for assessing the ecological quality and ecological grade (‘status’) of individual river stretches. The choice of reference sites and environmental predictor variables, the site classification and discrimination methods, the estimation of the expected fauna, and indices for comparing the agreement, or lack of it, between the observed and expected fauna, are all discussed. The indices are assessed on the reference sites and on a separate test set of 340 sites, which are subject to a wide range of types and degrees of impairment.  相似文献   
287.
In Europe, Britain was relatively early in being aware of the necessity of conserving natural coastal sites, though not as early as The Netherlands. In the 1960s and 1970s, increasing economic and tourist pressures in Europe prompted measures geared to the protection of other coasts in Europe. The promptness of the British reaction was a result of a sensitive public opinion and of powerful private trusts (National Trust with Enterprise Neptune) rather than of a commitment by the Government. In France a specific organization, in part inspired by the British principle, was set up. However, the French system is based much more on a public authority, theConservatoire de l’Espace Littoral et des Rivages Lacustres and on legislation (Coastal Law of 1986). Although very different in the beginning, French and British conservation politics today show many similarities, along with the similarities in the concerns of both countries.  相似文献   
288.
• Framework of indicators was established based on energy efficiency and recovery. • Energy neutrality potential of 970 wastewater treatment plants was evaluated. • Analysis of characteristics and explanatory factors was carried out. • Pathways for improving the energy neutrality potential were proposed. Wastewater treatment plants (WWTPs) consume large amounts of energy and emit greenhouse gases to remove pollutants. This study proposes a framework for evaluating the energy neutrality potential (ENP) of WWTPs from an integrated perspective. Operational data of 970 WWTPs in the Yangtze River Economic Belt (YREB) were extracted from the China Urban Drainage Yearbook 2018. The potential chemical and thermal energies were estimated using combined heat and power (CHP) and water source heat pump, respectively. Two key performance indicators (KPIs) were then established: the energy self-sufficiency (ESS) indicator, which reflects the offset degree of energy recovery, and the comprehensive water–energy efficiency (CWEE) indicator, which characterizes the efficiency of water–energy conversion. For the qualitative results, 98 WWTPs became the benchmark (i.e., CWEE= 1.000), while 112 WWTPs were fully self-sufficient (i.e., ESS≥100%). Subsequently, four types of ENP were classified by setting the median values of the two KPIs as the critical value. The WWTPs with high ENP had high net thermal energy values and relatively loose discharge limits. The explanatory factor analysis of water quantity and quality verified the existence of scale economies. Sufficient carbon source and biodegradability condition were also significant factors. As the CWEE indicator was mostly sensitive to the input of CHP, future optimization shall focus on the moisture and organic content of sludge. This study proposes a novel framework for evaluating the ENP of WWTPs. The results can provide guidance for optimizing the energy efficiency and recovery of WWTPs.  相似文献   
289.
This paper presents a holistic strategy on the interaction of activities in the Elbe river basin and their effects on eutrophication in the coastal waters of the German Bight. This catchment–coastal zone interaction is the main target of the EUROCAT (EUROpean CATchments, catchment changes and their impact on the coast) research project, with the Elbe being one of eight case studies. The definition of socio-economic scenarios is linked with the application of models to evaluate measures in the catchment by estimation of nutrient emissions with MONERIS (MOdelling Nutrient Emissions in RIver Systems), and their effects on coastal waters with the ecosystem model ERSEM (European Regional Seas Ecosystem Model). The cost effectiveness of reduction measures will then be evaluated by application of the CENER model (Cost-Effective Nutrient Emission Reduction) and a multi-criteria analysis. Finally, the interpretation of ecological integrity is used as a measure to describe ecological impacts in an aggregated form.  相似文献   
290.
以乌梁素海湿地生态修复为目标,在分析区域经济结构、流域生态环境与乌粱素海物理形态演变的基础上,明确了乌梁素海生态环境保护目标,提出乌梁素海湿地生态环境修复的措施.结果显示:巴彦淖尔市第二产业中一些污染较重的行业在经济结构中占有较大的比例;黄河过境可支配取水量不足;乌梁素海水体面积呈现溃缩状态且水质较差;乌梁素海生态环境修复应从区域产业结构转型、生态补水、区域农业、工业污染源削减及加强流域生态管理五个角度考虑.  相似文献   
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