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201.
荷电水雾振弦栅除尘效率影响因素及相关性分析   总被引:1,自引:0,他引:1  
为进一步提高荷电水雾振弦栅除尘器除尘效率,在自制模型基础上进行实验,在喷雾水压、喷嘴孔径一定时,以除尘效率η为实验结果,针对入口风速(V)、电场强度(E)和放电距离(L)3个影响因素进行实验研究。根据实验结果得到各影响因素与除尘效率的线性关系,利用MATLAB进行曲线拟合,得到拟合线性方程,通过SPSS软件分析了各因素针对除尘效率的权重关系为V>E>L,并得到V、E和L的相关性系数分别为:-0.264、1.529、0.016;实验结果表明:η与V成负相关、与E和L成正相关;V和E对η具有非常显著的影响,而L的影响相对较弱;综合拟合方程和相关性系数,建立了该项实验3因素对除尘效率影响的经验公式。效验表明该公式可靠,具有一定参考价值。  相似文献   
202.
Climate equity is a crucial but difficult element in negotiations on a post-2012 climate regime. With respect to the trading of greenhouse gas emissions the equity aspect is considered in the Kyoto Protocol which demands that emissions trading should be supplemental to domestic abatement efforts. The question arises whether a linking of the European Union Emissions Trading Scheme (EU ETS) to non-EU emission trading schemes or the Clean Development Mechanism (CDM) could have an impact on principles of climate justice and thus potentially affect ongoing negotiations. In this study, we present the results of a three step analysis: In a first step, it estimates mid-term greenhouse gas emission entitlements for Annex B and Non-Annex B countries for the year 2020 which keep within reach a stabilization of the CO2 concentration at 450 ppmv in the long-term. In the second step, the resulting emission entitlements are used as an input to an economic partial-equilibrium model in order to assess the shift of abatement efforts under different scenarios of linking the EU ETS. In a third step, we analyze the outcome of the economic model with respect to the future trend of European per capita emissions under the current EU ETS relative to different scenarios of linking the EU ETS. The model results indicate that European per capita emissions have to be reduced to a considerably smaller extent if a linking of the EU ETS is accompanied by an optimal design of the National Allocation Plans and if low-cost CO2 permits became available via the CDM to a large extent.
B. BrounsEmail:
  相似文献   
203.
In this article, per capita urban carbon emissions were decomposed into manufacturing,transportation, and construction sectors using logarithmic mean Divisia index(LMDI)method. This new decomposition method can provide information about specific drivers of carbon emissions, including urban growth and resident living standards, rather than general demographic and economic factors identified by traditional methods. Using four Chinese megacities(Beijing, Tianjin, Shanghai, and Chongqing) as case studies, we analyzed the factors that influenced per capita carbon emissions from 2010 to 2015. The results showed that per capita carbon emissions increased in Tianjin and Chongqing whereas decreased in Beijing and Shanghai, and that manufacturing was a key driving force. In these four megacities,energy conservation strategies were successfully implemented despite poor energy structure optimization during 2010–2015. Development of manufacturing and improvement of resident living standards in the cities led to an increase in carbon emissions. The unique dual-core urban form of Tianjin might mitigate the increased carbon emissions caused by the transportation sector. Reductions in carbon emissions could be achieved by further optimizing energy structures, limiting the number of private cars, and controlling per capita construction.  相似文献   
204.
Multivariate statistical techniques such as cluster analysis (CA), factor analysis (FA) were used for the evaluation of spatial variations and the interpretation of a large complex water quality data set of two selected estuaries of Malaysia. The two locations of interest with 10 sites in each location were Kuala Juru (Juru estuary) and Bukit Tambun (Jejawi estuary). Cluster analysis showed that some sites in both locations have similar sources of pollution from point or non-point sources whereas FA yielded four factors which are responsible for water quality variations explaining more than 80% of the total variance of the data set and allowed to group the selected water quality. Correlation analysis of the data showed that some parameters have strong association with other parameters and they share a common origin source. This study illustrates the usefulness of multivariate statistical analysis for evaluation and interpretation of complex data sets to get better information about the pollution sources/factors and understanding the behavior of the parameters in water quality for effective river water quality management.  相似文献   
205.
长江重庆段溶解性有机物的荧光特性分析   总被引:5,自引:0,他引:5  
蔡文良  许晓毅  罗固源  杜娴 《环境化学》2012,31(7):1003-1008
利用三维荧光光谱(EEMs),并结合平行因子分析(PARAFAC)及主成分分析(PCA),研究了长江重庆段溶解有机物(DOM)的荧光组分特征及其污染来源,并探讨了荧光强度同溶解性有机碳(DOC)及溶解氧(DO)的相关性.结果表明,PARAFAC模型识别出长江重庆段DOM由2类6个荧光组分组成,即类腐殖质荧光组分C1(350/422 nm)、C4(245,305/395 nm)、C5(260,340/420 nm)、C6(260/480 nm)及类蛋白荧光组分C2(275/300 nm)、C3(227,278/329 nm).在DOM来源组成中,陆源的类腐殖质含量占62.56%,类蛋白物质含量占31.31%.类腐殖质组分的荧光强度同DOC的含量存在明显的线性正相关(r=0.73),类蛋白组分的荧光强度同DO的含量呈明显的线性负相关(r=0.80).EEMs-PARAFAC不仅可以表征长江重庆段DOM的光谱特征,示踪长江重庆段的有机污染程度,还可以为三峡库区水体保护提供依据.  相似文献   
206.
李旻  陆平 《环境保护科学》2013,39(2):99-102
利用长荡湖4个监测断面数据进行分析,根据主成分分析结果,利用聚类分析对断面水质状况进行综合评价,总体看水质较好。并结合有机污染型的实际情况对控制湖体污染提出合理建议。  相似文献   
207.
基于层次分析法的城市灾害应急管理指标分析   总被引:1,自引:0,他引:1  
突发事件原生、次生、衍生和耦合灾害,造成城市灾害复杂化和扩大化,给城市应急管理带来重大挑战.基于应急管理体系的层次性、多样性和模糊性特点,分析了我国当前城市应急管理基本要素,运用层次分析法进行综合评价,得出了当前城市灾害应急管理工作重点是制定应急预案、应急管理与协调以及生命线系统恢复三个要素,并提出了相应建议.  相似文献   
208.
目的 通过简易的图像处理和目标检测方法,提高红外引信在复杂环境下的抗干扰能力。方法 分析红外引信在复杂背景中的噪声类别,采用“密度–距离”空间方法与像素生长方法进行预处理和目标检测,赋予像素2种属性,并进行量化分析,确定灰度平坦区域中的红外候选目标,并通过像素生长方法筛选候选目标中的真实目标。结果 计算在不同信噪比环境下算法的抗噪声干扰能力,当红外图像的SNR值在44.1~45.4时,算法检测效果理想。结论 红外引信探测过程中的复杂背景和随机噪声都会降低图像质量,考虑到红外目标所占像素数少,极易受噪声影响,需要运用自适应简易算法提高检测准确性。该算法有良好的实时性和抗干扰能力,为红外引信在目标检测中的环境适应性提供了理论依据。  相似文献   
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