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1.
徐州市电磁辐射环境的污染现状调查及评价   总被引:3,自引:0,他引:3  
调查了徐州市电磁辐射污染源的状况,分析了其电磁辐射环境质量的现状,并对全市电磁辐射环境质量进行了评价,指出了分析工作中存在的问题,提出了防治对策。  相似文献   

2.
介绍了餐饮业污染状况,对造成的原因进行了分析.提出了解决问题的措施。  相似文献   

3.
提高电除尘器除尘效率措施的研究进展   总被引:1,自引:0,他引:1  
高军凯  黄超  田莉 《环境污染与防治》2007,29(10):763-766,780
电除尘器在粉尘治理领域发挥着极其重要的作用.简要介绍了影响电除尘器除尘效率的主要因素.综述了近年来提高电除尘器效率措施的研究进展.着重介绍了几种新型电除尘器的除尘机制及除尘试验结果,评论了其除尘性能和应用前景,并对进一步的研究方向提出了看法.  相似文献   

4.
生态工业园区是实现生态工业和工业生态学的重要途径 ,代表了未来工业生态系统发展方向。本文从生态工业园区的概念出发 ,分析了生态工业园区的基本特征与功能 ,阐述了生态工业园区的类型及其建设的重点内容 ,介绍了生态工业园区建设实践 ,提出了生态工业园区建设的对策与措施  相似文献   

5.
调查了宝应县畜禽养殖业的发展现状及分布情况,阐述了该县畜禽养殖业的污染防治状况,分析了污染防治中存在的主要问题,并提出了当地畜禽养殖业污染防治的基本思路和治理措施,对贯彻落实防治措施提出了建议。  相似文献   

6.
在对旋转式滗水器进行了水力学和运动学计算的基础上,对旋转式滗水器进行了动力学计算,给出了其动力学计算公式,与水力学和运动学计算公式一起,共同给出了旋转式滗水器完整的设计计算公式.  相似文献   

7.
运用计算流体力学软件FLUENT,对旋风除尘器内部流场进行了数值模拟,利用模拟结果对旋风除尘器入口不同位置气流在除尘器顶部的环形空间的轨迹进行了分析研究,探明了气流在环形空间的运动规律和基本特征,阐明了旋风除尘器顶部"尘环"形成的根本原因,指出了粉尘发生短路的原因和多发区域并在此基础上就除尘器的增效问题给出了改进方案.  相似文献   

8.
中国排污权交易的法制建设探讨——以浙江省为例   总被引:1,自引:0,他引:1  
分析了浙江省排污权交易试点工作中存在的问题,探讨了美国、欧盟等国家和地区的排污权交易法制建设对中国的启示,对国家、地方2个层面进行了排污权交易法制建设的构想。最后,对浙江省排污权交易的法制建设进行了具体设计,并对排污权交易的法制建设提出了可操作性建议。  相似文献   

9.
水环境监测的质量控制与保证措施   总被引:1,自引:0,他引:1  
介绍了质量控制和质量保证体系,详细论述了质量监控方法及其注意事项,为样品监测的精确性提供了保障。  相似文献   

10.
正分析了火电厂项目主要的地下水污染源、污染途径,提出了优化选址、重点区域防渗等措施,模拟分析了防渗效果,提出了地下水的预警、监控及修复方案,为最大限度降低火电厂地下水环境影响提供了系统的设计方案。  相似文献   

11.
PCDD and PCDF were found in urban air particulates from St. Louis and Washington, D.C., and in sediments from the Great Lakes and Siskiwit Lake, Isle Royale. The similarity between the PCDD and PCDF found in air particulates and sediment samples and the presence of PCDD and PCDF in sediment from Siskiwit Lake (a location which can receive only atmospheric inputs) suggest that these compounds are emitted to the atmosphere from combustion sources. The historical input of PCDD and PCDF to dated sediment cores shows a strong increase since 1940, and this suggests that the incineration of chlorinated organic compounds is an important source of PCDD and PCDF to the environment.  相似文献   

12.
A comprehensive, systematic synthesis was conducted of daily time-series studies of air pollution and mortality from around the world. Estimates of effect sizes were extracted from 109 studies, from single- and multipollutant models, and by cause of death, age, and season. Random effects pooled estimates of excess all-cause mortality (single-pollutant models) associated with a change in pollutant concentration equal to the mean value among a representative group of cities were 2.0% (95% CI 1.5-2.4%) per 31.3 microg/m3 particulate matter (PM) of median diameter < or = 10 microm (PM10); 1.7% (1.2-2.2%) per 1.1 ppm CO; 2.8% (2.1-3.5%) per 24.0 ppb NO2; 1.6% (1.1-2.0%) per 31.2 ppb O3; and 0.9% (0.7-1.2%) per 9.4 ppb SO2 (daily maximum concentration for O3, daily average for others). Effect sizes were generally reduced in multipollutant models, but remained significantly different from zero for PM10 and SO2. Larger effect sizes were observed for respiratory mortality for all pollutants except O3. Heterogeneity among studies was partially accounted for by differences in variability of pollutant concentrations, and results were robust to alternative approaches to selecting estimates from the pool of available candidates. This synthesis leaves little doubt that acute air pollution exposure is a significant contributor to mortality.  相似文献   

13.
The stereoselectivity of R,S-venlafaxine and its metabolites R,S-O-desmethylvenlafaxine, N-desmethylvenlafaxine, O,N-didesmethylvenlafaxine, N,N-didesmethylvenlafaxine and tridesmethylvenlafaxine was studied in three processes: (i) anaerobic and aerobic laboratory scale tests; (ii) six wastewater treatment plants (WWTPs) operating under different conditions; and (iii) a variety of wastewater treatments including conventional activated sludge, natural attenuation along a receiving river stream and storage in operational and seasonal reservoirs. In the laboratory and field studies, the degradation of the venlafaxine yielded O-desmethylvenalfaxine as the dominant metabolite under aerobic and anaerobic conditions. Venlafaxine was almost exclusively converted to O-desmethylvenlafaxine under anaerobic conditions, but only a fraction of the drug was transformed to O-desmethylvenlafaxine under aerobic conditions. Degradation of venlafaxine involved only small stereoisomeric selectivity. In contrast, the degradation of O-desmethylvenlafaxine yielded remarkable S to R enrichment under aerobic conditions but none under anaerobic conditions. Determination of venlafaxine and its metabolites in the WWTPs agreed well with the stereoselectivity observed in the laboratory studies. Our results suggest that the levels of the drug and its metabolites and the stereoisomeric enrichment of the metabolite and its parent drug can be used for source tracking and for discrimination between domestic and nondomestic wastewater pollution. This was indeed demonstrated in the investigations carried out at the Jerusalem WWTP.  相似文献   

14.
Abstract

A comprehensive, systematic synthesis was conducted of daily time-series studies of air pollution and mortality from around the world. Estimates of effect sizes were extracted from 109 studies, from single- and multipollutant models, and by cause of death, age, and season. Random effects pooled estimates of excess all-cause mortality (single-pollutant models) associated with a change in pollutant concentration equal to the mean value among a representative group of cities were 2.0% (95% CI 1.5-2.4%) per 31.3 μg/m3 particulate matter (PM) of median diameter <10 μm (PM10); 1.7% (1.2-2.2%) per 1.1 ppm CO; 2.8% (2.1-3.5%) per 24.0 ppb NO2; 1.6% (1.1-2.0%) per 31.2 ppb O3; and 0.9% (0.7-1.2%) per 9.4 ppb SO2 (daily maximum concentration for O3, daily average for others). Effect sizes were generally reduced in multipollutant models, but remained significantly different from zero for PM10 and SO2. Larger effect sizes were observed for respiratory mortality for all pollutants except O3. Heterogeneity among studies was partially accounted for by differences in variability of pollutant concentrations, and results were robust to alternative approaches to selecting estimates from the pool of available candidates. This synthesis leaves little doubt that acute air pollution exposure is a significant contributor to mortality.  相似文献   

15.
剩余污泥浓缩脱水投药量优化和模型建立   总被引:1,自引:1,他引:0  
李振华 《环境工程学报》2011,5(12):2797-2800
应用高分子阳离子絮凝剂(CPF-100)和聚丙烯酰胺(PAM)对污水厂剩余污泥进行浓缩脱水实验,研究表明:CPF-100的浓缩脱水效果优于PAM;当CPF-00投加量为1.16‰时,污泥沉降性能改善程度为37.51%;且在CPF-100投加量逐渐增大的初始阶段,污泥沉降性能改善程度随投加量的增加而增大,但CPF-100投加量也不宜过大,当CPF-100投加量超过1.16‰后,反而会使浓缩脱水效果变差。同时,建立了污泥沉降性能改善程度与絮凝剂CPF-100投加量、沉降时间之间的数学模型,其能较好地反映污水厂剩余污泥的浓缩脱水效果。  相似文献   

16.
17.
The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment.  相似文献   

18.
骆马湖富营养化和生态状况调查与评价   总被引:5,自引:0,他引:5  
为了了解骆马湖水质状况,在2005年对骆马湖富营养化状态和生态特性进行了调查,并结合“十五”期间的监测资料进行了分析。2005年骆马湖水体中总氮和总磷的平均值超《地表水环境质量标准》(GB3838-2002)中Ⅲ类,超标情况分别为0.78倍和0.54倍,达到湖库特定项目Ⅳ类水标准,骆马湖处于轻度富营养化状态。对骆马湖生态特征分析表明,由于该湖泊的形态以及“藻型浊水状态”和“泥沙型浊水状态”交替出现,遏制了湖水从高营养盐含量向全面富营养化状态演变,保障了底栖动物的良好生长环境,从而形成了骆马湖独特的环境生态平衡。  相似文献   

19.
A procedure based on solid-phase microextraction (SPME) and gas chromatography coupled with mass spectrometry (GC-MS) was developed and validated in order to analyse 10 phenols in water samples. The optimised conditions were obtained using polyacrylate fibre (PA), 20ml of sample volume, 10% NaCl, pH 4.0 and direct extraction at 35 degrees C and 1000rpm, for 40min. The linear range and quantification limits for these compounds by SPME-GC-MS were defined. An evaluation of the main uncertainty sources of this method is included, which allows expanded uncertainties in the 9.4-35% range for the majority of the compounds. The main source of uncertainty is associated with matrix effects. The validated method is suitable for monitoring the production and distribution of potable water and was used, in field trials, for the analysis of samples from main intakes of water (surface or underground) and from water supply system of a large area (Lisbon and neighbour municipalities).  相似文献   

20.
The chlorination and condensation of acetylene at low temperatures is demonstrated using copper chlorides as chlorinated agents coated to model borosilicate surfaces. Experiments with and without both a chlorine source and borosilicate surfaces indicate the absence of gas-phase and gas-surface reactions. Chlorination and condensation occur only in the presence of the copper catalyst. C2 through C8 organic products were observed in the effluent; PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed that is consistent with the observed product distributions. Similar experiments with dichloroacetylene indicate greater reactivity in the absence of the copper catalyst. Reaction is observed in the gas-phase and in the presence of borosilicate surfaces at low temperatures. The formation of hexachlorobenzene is only observed in the presence of a copper catalyst. PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed for the formation of hexachlorobenzene from dichloroacetylene.  相似文献   

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