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171.
克拉玛依市区大气尘污染研究   总被引:2,自引:0,他引:2  
对克拉玛依市区大气尘污染的特征及变化规律进行了全面的分析和研究。结果表明,市区的尘污染有加重的趋势,降尘属中度污染,道路尘污 染也较严重。提出了一些具体的防治对策。  相似文献   
172.
针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。  相似文献   
173.
近年来,随着阻燃剂多溴联苯醚(PBDEs)和以邻苯二甲酸酯(PAEs)为代表的传统型塑化剂(LPs)的逐步禁用或限用,有机磷系阻燃剂(PFRs)等新型阻燃剂及替代型塑化剂(APs)的生产和使用呈逐年增长的趋势,其环境污染特征和人体暴露健康风险值得引起广泛关注.目前,灰尘已广泛用于室内环境中PBDEs、PFRs和LPs等半挥发性有机污染物(SVOCs)的污染特征评估,而关于室内灰尘中APs的污染特征则鲜有报道.本研究以广州市42户普通居民家庭为研究对象,采集家庭室内灰尘并分析了PFRs、PBDEs、LPs和APs的含量及组成特征.结果表明,PFRs、PBDEs、LPs和APs在室内灰尘中均有广泛检出,其含量分别为593.28~11531.56、13.45~27029.13、40494.83~1154497.16和15365.19~1013352.51 ng·g-1.大多数家庭中,PFRs和部分APs在灰尘中的含量呈现高于PBDEs和LPs的特征,PFRs和APs等新型污染物的人体暴露健康风险需引起高度关注.采用暴露模型评估人体经灰尘摄入和皮肤接触对目标污染物的日均暴...  相似文献   
174.
沙尘不同的垂直分布对大气的加热作用不同,通过卫星观测结合数值模拟,可以更清楚地了解沙尘辐射加热作用,有利于理解沙尘对该地区大气热结构的影响机制.因此,本研究利用CALIPSO气溶胶产品和SBDART模式,分析了2007—2020年塔克拉玛干沙漠和青藏高原沙尘气溶胶及其短波加热率的时空分布特征.结果表明,塔克拉玛干沙漠和青藏高原的年平均沙尘气溶胶光学厚度(DAOD,532 nm)分别为0.300~0.350和0.086~0.108,平均值分别为0.328和0.097.塔克拉玛干沙漠季节平均DAOD的最大、最小值分别出现在春季和冬季,而青藏高原的最大、最小值分别出现在夏季和秋季.塔克拉玛干沙漠和青藏高原的沙尘消光系数(σD)最大值分别出现在春季和夏季.2007—2020年,两地的σD在春季均呈增加趋势,而在秋季则呈减小趋势.春季和夏季的短波沙尘加热率(SW DHR)均大于其它两个季节,其中春季最大,塔克拉玛干沙漠上空冬季最弱,青藏高原上空秋季最弱.春夏季,青藏高原北坡存在较强沙尘加热层,其顶部高于5 km,其强度及高值区从春季到冬季逐渐减小.从年变化来看,春季短波加热率呈加强趋势,秋季呈减...  相似文献   
175.
Abstract: One potential contributor to the worldwide decline of bird populations is the increasing prevalence of roads, which have several negative effects on birds and other vertebrates. We synthesized the results of studies and reviews that explore the effects of roads on birds with an emphasis on paved roads. The well‐known direct effects of roads on birds include habitat loss and fragmentation, vehicle‐caused mortality, pollution, and poisoning. Nevertheless, indirect effects may exert a greater influence on bird populations. These effects include noise, artificial light, barriers to movement, and edges associated with roads. Moreover, indirect and direct effects may act synergistically to cause decreases in population density and species richness. Of the many effects of roads, it appears that road mortality and traffic noise may have the most substantial effects on birds relative to other effects and taxonomic groups. Potential measures for mitigating the detrimental effects of roads include noise‐reduction strategies and changes to roadway lighting and vegetation and traffic flow. Road networks and traffic volumes are projected to increase in many countries around the world. Increasing habitat loss and fragmentation and predicted species distribution shifts due to climate change are likely to compound the overall effects of roads on birds.  相似文献   
176.
介绍和分析现代道路交通安全治理的3种思想。应用其中非常值得我国借鉴的系统治理思想对现行道路交通安全立法进行分析。现行道路交通安全立法仅围绕驾驶人的行为控制而设计,围绕道路交通安全管理部门的职能而展开,在很大程度上局限于道路交通秩序管理,在体系上存在缺失,影响道路交通安全治理的工作及其成效。基于当前形势分析,我国有必要也有条件借鉴道路交通安全系统治理的先进思想,重新构建道路交通安全立法的体系。该体系的重构需从道路安全保障、车辆安全保障、交通秩序管理、运输安全运营、交通事故处理等5个方面展开。  相似文献   
177.
采用高压水和喷嘴的引射原理,使水射流通过喷嘴后高效雾化,达到降尘的目的,并主要沉降5μm以下对人体具有致命危害的呼吸性粉尘。当更换喷嘴后也可进行积上和物体的表面清洗。  相似文献   
178.
Solid waste management is one of the major environmental concerns around the world. Cement kiln dust (KKD), also known as by-pass dust, is a by-product of cement manufacturing. The environmental concerns related to Portland cement production, emission and disposal of CKD is becoming progressively significant. CKD is fine-grained, particulate material chiefly composed of oxidized, anhydrous, micron-sized particles collected from electrostatic precipitators during the high temperature production of clinker. Cement kiln dust so generated is partly reused in cement plant and landfilled. The beneficial uses of CKD are in highway uses, soil stabilization, use in cement mortar/concrete, CLSM, etc.Studies have shown that CKD could be used in making paste/mortar/concrete. This paper presents an overview of some of the research published on the use of CKD in cement paste/mortar/concrete. Effect of CKD on the cement paste/mortar/concrete properties like compressive strength, tensile strength properties (splitting tensile strength, flexural strength and toughness), durability (Freeze–thaw), hydration, setting time, sorptivity, electrical conductivity are presented. Use of CKD in making controlled low-strength materials (CLSM), asphalt concrete, as soil stabilizer, and leachate analysis are also discussed in this paper.  相似文献   
179.
Plumes of atmospheric aerosol have been studied using a rangeof satellite and ground-based techniques. The Sea-viewing WideField-of-view Sensor (SeaWiFS) has been used to observe plumesof sulphate aerosol and Saharan dust around the coast of theUnited Kingdom. Aerosol Optical Thickness (AOT) was retrievedfrom SeaWiFS for two events; a plume of Saharan dusttransported over the United Kingdom from Western Africa and aperiod of elevated sulphate experienced over the Easternregion of the UK. Patterns of AOT are discussed and related tothe synoptic and mesoscale weather conditions. Furtherobservation of the sulphate aerosol event was undertaken usingthe Advanced Very High Resolution Radiometer instrument(AVHRR). Atmospheric back trajectories and weather conditionswere studied in order to identify the meteorologicalconditions which led to this event. Co-located ground-basedmeasurements of PM10 and PM2.5 were obtained for 4sites within the UK and PM2.5/10 ratios were calculatedin order to identify any unusually high or low ratios(indicating the dominant size fraction within the plume)during either of these events. Calculated percentiles ofPM2.5/10 ratios during the 2 events examined show thatthese events were notable within the record, but were in noway unique or unusual in the context of a 3 yr monitoringrecord. Visibility measurements for both episodes have beenexamined and show that visibility degradation occurred duringboth the sulphate aerosol and Saharan dust episodes.  相似文献   
180.
Settled dust has been collected inside the main foyers ofthree University buildings in Wolverhampton City Centre,U.K. Two of the three buildings are located in a streetcanyon used almost exclusively by heavy duty dieselvehicles. The dust was collected on adhesive carbonspectro-tabs to be in a form suitable for analysis byscanning electron microscope and energy dispersive X-rayanalysis. Using these analytical techniques, individualparticle analysis was undertaken for morphology andchemistry. Seasonal variations and variations due tolocation were observed in both the morphologicalmeasurements and chemical analysis. Many of the differencesappear attributable to the influence of road traffic, inparticular, the heavy duty diesel vehicles, travellingalong the street canyon.  相似文献   
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