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461.
利用ADMS-城市模型模拟分析鞍山市大气环境质量   总被引:2,自引:0,他引:2  
方力 《环境保护科学》2004,30(6):8-10,13
利用鞍山市 2 0 0 2年的TSP(总悬浮颗粒物 )和SO2 (二氧化硫 )大气环境监测资料、污染源排放清单资料和气象资料 ,以及ADMS -城市大气扩散模型进行了鞍山市大气环境质量分析。结果表明 :鞍山市低架源对地面浓度的贡献较大 ,高架源对地面浓度的贡献相对较小。  相似文献   
462.
国家标准GB/T13201-91推荐基于单箱模型推导出来的A值法制定地方大气污染物排放总量标准,该文在放弃了控制区呈圆形的假设之后推导出可利用风向大气稳定度联合频率的更为详细的单箱模型,并用于计算杭州、宁波、温州、衢州的SO2排放年总控制量,在温州和衢州得到不同于A值法的结果。   相似文献   
463.
城市大气环境质量评价模糊识别理论模型   总被引:16,自引:0,他引:16       下载免费PDF全文
本文提出一种新的大气环境质量评价理论模型——模糊识别模型。提出了大气质量评价的指标综合权重矩阵概念及其确定方法。   相似文献   
464.
为了加快大气降尘样品的蒸发速度和报出数据的及时,经过分析总结,得出蒸发样品的步骤为:先电热套蒸发再水浴蒸发最后用电热板蒸发,这样既可以节省时间,又可以节约能耗,避免样品在空气中放置时间过长,空气中的尘粒进入样品中,影响样品测定的结果。  相似文献   
465.
Based on available literature data of [NO2 ], steady-state [·OH], and ·OH generation rate upon nitrate photolysis in environmental aqueous samples under sunlight, the steady-state [·NO2], could be calculated. Interestingly, one to two orders of magnitude more ·NO2 would be formed in photochemical processes in atmospheric water droplets compared to transfer from the gas phase. The relative importance of nitrite oxidation compared to nitrate photolysis as an ·NO2 source would be higher in atmospheric than in surface waters. The calculated levels of ·NO2 could lead to substantial transformation of phenol into nitrophenols in both atmospheric and surface waters.  相似文献   
466.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October-December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   
467.
It is known that fugitive dust can cause human health and environmental problems, alone or in combination with other air pollutants. These problems are referred to as ‘external costs’ that have been traditionally ignored. However, there is a growing interest towards quantifying externalities to assist policy and decision-making. With this in mind, the present study aimed at discussing the environmental regulations that deal with fugitive dust, the impact of fugitive dust on human health and global climate system, and the available methods for calculating fugitive dust externalities. The damage cost associated with human health and global environmental problems was predicted based on the environmental strategy priority model. The damage cost estimated by the model ranged from 40 to 374 EUR/kg of emitted fugitive dust with a mean value of 120 EUR/kg of emitted fugitive dust. It was also found that PM2.5 and PM10 have contributed to about 60% and 36% of the estimated damage cost, respectively. The remaining 4% was attributed to both nitrate and sulfate aerosols.  相似文献   
468.
大气污染预报技术及有关防治对策的研究   总被引:3,自引:1,他引:2  
依据历史监测数据,研究了大气污染预测预报的方法及污染防治对策。利用主分量分析、多元逐步回归、拟合与逼近等方法,进行了天气预报参数与主要污染物的关系研究,建立了大气污染预测预报模型,制定了大气污染警戒值及警戒措施。模型可做48小时内大气污染预报及10日内大气污染趋势分析。  相似文献   
469.
Hurricane as one of the most destructive natural hazards can make a devastating impact on the industrial equipment, especially atmospheric storage tanks, leading to the release of stored chemicals and disastrous safety and environmental issues. These catastrophic consequences are caused not only by strong winds but also by the torrential rainfall and inundating floods. The objective of this study is to present a risk-based methodology for assessing and reducing the vulnerability of atmospheric storage tanks to hurricanes. Considering the shell buckling, flotation, sliding, and roof sinking as dominant failure modes of atmospheric storage tanks during hurricanes, Bayesian network (BN) has been employed to combine the failure modes while considering their conditional dependencies. The probability updating feature of the developed BN was employed to indicate that the flood is the most critical hazard during hurricanes while the impact of wind and rainfall cannot be neglected. Extending the developed BN to an influence diagram, the cost-benefit filling of storage tanks with water prior to the advent of hurricanes was shown as a viable measure for reducing the damage probability. The results show that the proposed methodology can be used as an effective decision support tool for assessing and reducing the vulnerability of atmospheric storage tanks to natural hazards.  相似文献   
470.
Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources, chemical mechanisms, and transport processes of air pollution in land, sea, and atmosphere. We present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent years. China has developed a series of coastal ocean boundary layer detection t...  相似文献   
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