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191.
Real-time chemical measurements have been made as part of a field study of air quality in the city and harbour of Cork, Ireland. The data relate to the year 2008, with particular attention paid to the period between May and August. Eight air quality parameters were measured: NO, O3, NO2, SO2, EC, OC, particulate SO42? and PM2.5. The data have been used in a novel way involving wind and temporal averaging, along with Principal Component Analysis (PCA) and Positive Matrix Factorisation (PMF) methodologies to extrapolate major source contributions for PM2.5. It is demonstrated that continuous monitoring of standard air quality parameters, such as NO, NO2, SO2, along with EC, OC and particulate SO42?, can be used to provide relevant, cost-effective initial estimates of source contributions to ambient PM2.5 levels. It is also shown that the benefit of including OC and particulate SO42? in the monitoring protocol is considerable. Three major source groups of ambient PM2.5 mass in Cork were identified and quantified using this combined monitoring and modelling approach; road transport (19%), domestic solid fuel burning (14%) and oil-fired domestic and industrial boilers, including power generation plants (31%).  相似文献   
192.
介绍了内电解技术的基本原理和特点,详细阐述了内电解技术处理印染、制药等多种有毒有害工业废水的应用进展,总结了内电解技术目前存在的主要问题和在工艺优化、新型材料和反应器形式开发三个方面的改进措施,展望了内电解技术未来的发展趋势和研究方向。  相似文献   
193.
The phytoavailabilities and potential remobilization of potentially toxic elements (PTEs) such as Zn, Pb, Cd, As, and Sb were assessed in contaminated technosols from former mining and smelting sites. The PTE concentrations in soil pore water (SPW) and diffusive gradients in thin films (DGT)-measured concentration (C DGT) methods were used to assess the bioavailabilities of PTE and their remobilization in this study. Together with classical Chelex-100 DGT probes to measure Zn, Cd, and Pb, novel ferrihydrite-backed DGT were used for As and Sb measurements alongside with Rhizon soil moisture sampler method for SPW sampling. To assess the phytoavailabilities of PTE, a germination test with dwarf beans as a plant indicator was used for this purpose. Dwarf bean primary leaves showed high Zn concentrations in contrast to Pb and Cd which showed low phytoavailabilities. Despite As and Sb are present in high concentrations in the mine tailings, their phytoavailabilities indicate very low bioavailabilities. The amounts of Zn, Pb, Cd, As, and Sb extracted with DGT devices correlated well with the total dissolved PTE concentrations in the SPW. The highest R values were observed for Zn, followed by Cd and Pb, indicating the ability of the soil to sustain SPW concentrations, which decreased in that order. Good correlations were also observed between each of dissolved PTE concentrations in SPW, DGT-measured PTE concentrations (C DGT), and the accumulation of PTE in dwarf bean primary leaves. It could be concluded that the use of Rhizon soil moisture samplers and DGT methods may be considered to be a good methods to predict the PTE bioavailabilities in contaminated technosols.  相似文献   
194.
生物法是处理难降解有机物的一种重要方法,通过投加活性污泥,采用振荡培养法,研究了以2-羟基-3-萘甲羟肟酸(H205)为唯一碳源的单基质条件、外加碳源和氮源的共基质条件下H205的生物降解过程.结果表明:(1)单基质条件下,不同初始质量浓度(10~50 mg/L)H205的生物降解符合一级动力学模型方程.(2)共基质条...  相似文献   
195.
挥发性有机物控制技术评价指标体系初探   总被引:1,自引:1,他引:0  
阐述了挥发性有机物(VOCs)控制技术的评价原则、评价步骤和影响 VOCs 控制技术评价的因素,从技术、经济、社会和其他方面初步构建了 VOCs 控制技术的评价指标体系.进一步介绍了评价指标的量化方法.VOCs控制技术评价指标体系的建立,为科学、全面、客观地评价和筛选 VOCs 控制技术奠定坚实的基础.  相似文献   
196.
采用有机物前驱法制备了3种尖晶石型铝酸盐催化剂(CoAl_2O_4,ZnAl_2O_4,CoAl_2O_4)。采用FTIR,XRD,UV-Vis DRS等技术对催化剂进行表征,并将催化剂应用于CO_2的光催化还原。表征结果显示:除CoAl_2O_4外,CoAl_2O_4和ZnAl_2O_4在煅烧时均直接形成尖晶石相;CoAl_2O_4,CoAl_2O_4,ZnAl_2O_4的平均粒径分别为25.21,21.35,23.26 nm,禁带宽度分别为1.77,1.45,3.82 eV。分别以煅烧温度为900℃、煅烧时间为4 h时制得的ZnAl_2O_4,CoAl_2O_4,CoAl_2O_4为催化剂,在催化剂加入量为1.5 g/L、CO_2流量为200 mL/min、反应温度为60℃的条件下光催化反应8 h,甲酸产生量分别为443.54,365.65,241.39μmol/g。  相似文献   
197.
重庆城区不同粒径颗粒物元素组分研究及来源识别   总被引:2,自引:2,他引:0  
为研究重庆市大气颗粒物的污染特征及其来源,于2010年3—10月在主城区分别采集PM1.0、PM2.5和PM103种粒径的颗粒物样品,利用XRF分析其中的26种元素浓度。结果表明,重庆市主城区S元素在各粒径中含量都较高,细粒子中K的含量较高,粗粒子中Si、Ca和Fe的浓度较大。富集因子分析表明,主城区Cd、S、Se等污染元素的富集系数较大,且粒径越小,富集现象越明显。利用因子分析得出土壤风沙、扬尘、燃煤的燃烧、机动车燃油产生的尾气排放、生物质燃烧排放是重庆市颗粒物污染的主要来源。  相似文献   
198.
The study presents a new methodology to quantify spatiotemporal dynamics of climate change vulnerability at a regional scale adopting a new conceptual model of vulnerability as a function of climate change impacts, ecological stability, and socioeconomic stability. Spatiotemporal trends of equally weighted proxy variables for the three vulnerability components were generated to develop a composite climate change vulnerability index (CCVI) for a Mediterranean region of Turkey combining Landsat time series data, digital elevation model (DEM)-derived data, ordinary kriging, and geographical information system. Climate change impact was based on spatiotemporal trends of August land surface temperature (LST) between 1987 and 2016. Ecological stability was based on DEM, slope, aspect, and spatiotemporal trends of normalized difference vegetation index (NDVI), while socioeconomic stability was quantified as a function of spatiotemporal trends of land cover, population density, per capita gross domestic product, and illiteracy. The zones ranked on the five classes of no-to-extreme vulnerability were identified where highly and moderately vulnerable lands covered 0.02% (12 km2) and 11.8% (6374 km2) of the study region, respectively, mostly occurring in the interior central part. The adoption of this composite CCVI approach is expected to lead to spatiotemporally dynamic policy recommendations towards sustainability and tailor preventive and mitigative measures to locally specific characteristics of coupled ecological–socioeconomic systems.  相似文献   
199.
重庆市主城区PM 10 与能见度相关性研究   总被引:2,自引:0,他引:2  
分析了2000年以来重庆市主城区能见度变化趋势及2006年PM10的污染现状,能见度和PM10质量浓度负相关,尤其采样期间的相关系数为-0.76。根据PM10源解析和PM10成分与能见度的相关性分析结果,提出应重点控制燃煤和机动车尾气污染。  相似文献   
200.
为有效预警原油储备区储罐气体泄漏,制定气体探测器布置优化方案,以某大型原油站库为例,基于CFD法和FLACS软件模拟原油泄漏及可燃蒸汽云溢散分布,通过分析蒸汽云扩散规律,实现全方位气体探测器优化布置.结果表明:原油储罐区探测器分别布置在区块21-2、6-1、31-1、40-2,且每个罐组总计布置16处;优化设置方案可满...  相似文献   
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