苏州河近20年水质状况研究

通过对近20年来上海市苏州河沿程13个断面的常规水质监测教据进行整理分析,总结各常规监测指标项目的变化趋势.并通过分析沿程水质变化和几项重要水质指标的比值变化并探讨了变化的原因,从而得出上海市苏州河水质得到明显改善的结论.     

基于因子分析的电缆烟气毒性评估

<正>火灾条件下电缆燃烧烟气的毒性分析对于电缆火灾安全研究非常重要。为了研究典型电缆燃烧烟气的组分及毒性大小定量,通过搭建试验装置并进行实验研究。对采集的实验数据采用FED模型进行了烟气的毒性评价,并进一步采用因子分析法对组分烟气数据进行分析。分析结果表明,基于因子分析法的烟气毒性评价方法与FED模型分析结果趋于一致,但此方法可以揭示出更多有用信息用以指导电缆火灾危险性评价。研究为电缆燃烧烟气的毒性效应评价提出了一种新的思路。     

Factor decomposition of carbon emissions in Chinese megacities

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.     

卧龙湖浮游动物丰度的季节变化及其与水环境因子的关系

为给卧龙湖(国家良好湖泊生态环境保护试点)生态保护工作提供依据,文章于2014年5~10月对卧龙湖的浮游动物群落结构和不同水环境因子开展了监测,以期明确两者之间的关系。结果表明:研究区浮游动物丰度高,均值达到128.2×10~3 ind/L,浮游动物丰度季节差异显著(P<0.05),夏季(196.2×10~3 ind/L)>春季(154.0×10~3 ind/L)>秋季(25.1×10~3 ind/L);通过克里格插值分析,发现研究区浮游动物季节分布的空间异质性高,春季浮游动物丰度呈现从湖岸带到湖心递减趋势,南部是浮游动物的主要聚集区,而在夏秋季节,浮游动物丰度的高值区域逐渐向东北湖区偏移;通过典范对应分析,研究区内浮游动物分布主要受浊度、温度、营养物质和污染物等因素的影响,同时夏秋季节浮游动物丰度的高值区域逐渐向东北湖区偏移可能与城北明渠在湖区东北部汇入有关。     

荷电水雾振弦栅除尘效率影响因素及相关性分析

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。     

“九五”期间大石桥市大气环境质量变化趋势分析

通过对大石桥市“九五”期间大气监测资料的分析研究,从中找出该期间大石桥市大气环境质量的变化规律与发展趋势,分析出大气污染的原因与特征,进一步提出综合防治建议。     

废水污染物总量控制探讨——沈阳高压开关厂技术改造项目实例

以沈阳高压开关厂技术改造项目为例，根据国家和地方对水污染物总量控制的要求，对企业的总量控制环境管理进行了探讨，并提出具体措施．给出了相应的削减量，实现总量控制目标．     

我国环境污染的因子分析

改革开放以来，我国经济发展迅速，取得了举世瞩目的伟大成就。但在经济快速发展的同时，也带来了一些负面效应，如环境污染。本文采用因子分析法对全国31个省、自治区、直辖市的环境污染进行了分析、评价，并运用SPSSl0．0统计软件对数据进行了计算、处理。通过分析表明我国目前环境污染较为严重，本文通过分析、评价可以为我国的环境污染防治提供一定的理论基础。     

Bayesian Ecological Regression with Latent Factors: Atmospheric Pollutants Emissions and Mortality for Lung Cancer

In this work we propose a Bayesian ecological analysis in which a latent variable summarizes data on emissions of atmospheric pollutants. We specified a hierarchical Bayesian model with spatially structured and unstructured random terms with a nested latent factor model. This can be considered a combination of the convolution spatial model of Besag et al. (1991) and an ecological regression analysis in which a latent variable plays the role of the covariate. The unified approach allows to proper account for the uncertainty in the latent score estimation in the regression analysis. The Bayesian Latent Factor model is used to summarize the information on environmental pressure derived from three stressors: Carbon Monoxide, Nitrogen Oxides and Inhalable Particles. We found evidence of positive correlation between Lung cancer mortality and environmental pressure indicators, in males, Tuscany (Italy), 1995–1999. Environmental pressure seems to be restricted to fourteen municipalities (top 5% of the Latent Factor distribution). The model identified two areas with high point source emissions.     

A composite receptor and dispersion model approach for estimation of effective emission factors for vehicles

It is difficult to estimate vehicular emission factors at traffic junctions for use in dispersion modelling studies. Firstly, because the vehicles are in various modes of operation and secondly, it is difficult to delineate the effects of other contributing sources, mainly the effects of road dust and deposited constituents, which are very prominent at traffic junctions in India. Factor analysis-multiple regression (FA-MR), a receptor modelling technique has been used in this study for apportioning the contributing sources. The measurement data consist of one year's temporal variation of suspended particulate matter (SPM), analysed for its trace metal constituents, and two gaseous components NO₂ and SO₂ at two traffic junctions in Mumbai (India). FA-MR apportioned 40% of the observed SPM to road dust and 15% to vehicular sources. Of the total Pb observed in the SPM, FA-MR apportioned 60% to vehicular sources and 20% to road dust. The field-observed vehicular counts, meteorological parameters and road geometry were used in California line source dispersion model to estimate the effective vehicular emission factor for Pb at one traffic junction. This derived emission factor was used to predict the Pb concentration at second (independent observation) traffic junction. The result was found to be more satisfactory than using default emission factors obtained from literature. Similarly, effective vehicular emission factor for NO₂ was also evaluated for one site and tested for predicting concentrations at the other site.