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881.
沈阳市冬季一次严重污染天气过程成因分析 总被引:1,自引:1,他引:0
为探讨沈阳市冬季重污染天气的初步成因。以2013年1月11日~16日沈阳市发生的一次严重污染天气为例,利用中国气象局的MICAPS系统和美国的HYSPLT模式,从污染形成的天气背景、污染物扩散受地形的影响情况以及外来污染物输送的气流轨迹等几方面综合分析,从而探讨此次严重污染过程的成因:长白山小高压和西部倒槽双重系统的控制下,地面吹东北风,风速较小,湿度大,不利于污染物的水平扩散;有较强接地逆温存在时,不利于污染物的垂直扩散,导致近地面污染物累积;受来自于北部和东北部低层气流的影响,将内蒙古、辽宁东北部的污染物携带到沈阳地区汇聚。 相似文献
882.
选取最高占据轨道能量EHOMO、最低空轨道能量ELUMO、分子体积Vm、分配系数ClgP、偶极距μ及二阶分子连接性指数2X作为烃基黄药类捕收剂的结构性参数,通过回归分析,建立了烃基黄药类捕收剂的定量结构-生物降解性能关系模型(QSBR),并进行了预测.结果表明,ELUMO、2X(即分子最低空轨道能量水平和二阶分子连接性指数)对烃基黄药类捕收剂的生物降解性能有显著影响. 相似文献
883.
884.
利用2014年徐州市环境监测中心站SO2,NO2,PM10和PM2.5质量浓度的逐日监测资料及同期徐州市气象局的常规气象观测资料,分析了徐州市空气质量的现状及变化特征,探讨了SO2,NO2,PM10和PM2.5浓度与气象条件的关系。结果表明:徐州市空气质量以良和轻度污染为主,夏、秋季的空气质量好于冬、春季,冬季空气质量最差;较大的降水量过后,空气质量类别为优或者良,降水量较小时,污染物去除效果不明显;风速越大,越有利于污染物的扩散;雾和灰霾天气条件下,空气质量较差。 相似文献
885.
Andrea A. Roch Christian Wilde Zhenzhong Hu Oleg Nepotchatykh Yevgen Nazarenko Parisa A. Ariya 《环境科学学报(英文版)》2017,29(7):41-53
Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide (CO2) which contribute to climate change and atmospheric pollution. There is a need for green and sustainable solutions to remove air pollutants, as opposed to conventional techniques which can be expensive, consume additional energy and generate further waste. We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces, to remove CO2, and undesired organic air pollutants using natural particles, while generating oxygen. This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO2 with a conversion rate of approximately 4% CO2 per hour, generating a steady supply of oxygen (6 mmol/hr), while nanoparticles effectively remove several undesired organic by-products. We also showed algal waste of the bioreactor can be used for mercury remediation. We estimated the potential CO2 emissions that could be captured from our new method for three industrial cases in which, coal, oil and natural gas were used. With a 30% carbon capture system, the reduction of CO2 was estimated to decrease by about 420,000, 320,000 and 240,000 metric tonnes, respectively for a typical 500 MW power plant. The cost analysis we conducted showed potential to scale-up, and the entire system is recyclable and sustainable. We further discuss the implications of usage of this complete system, or as individual units, that could provide a hybrid option to existing industrial setups. 相似文献
886.
丘陵地区工业污染源的大气影响预测,由于特殊的地理环境,大气扩散模式中最大地面浓度Cm及其距排气筒的距离Xm的烟轴He需修正。 相似文献
887.
基于废水中的污染物在热态、碱性和一定硬度的情况下,从水中析出的特点,探究了温度、pH和硬度对处理效果的影响。在此基础上,提出了热析+混凝+气浮处理工艺,并进行了设计和调试。实际运行结果表明,在水温在65~70℃、出水pH值在7.5~8.5和MgSO4用量在40~65 mg/L范围内的情况下,对析出的污染物进行混凝,再经过涡凹气浮对高温废水中的絮体稳定、高效的分离,CODCr和TP的最低去除率分别为89.4%和90.3%,各项指标完全达到设计要求。 相似文献
888.
利用大气污染源和环境质量监测等资料,计算分析了锦州市区环境空气质量现状。结果表明,锦州市环境空气质量呈现逐年改善的趋势,空气污染以煤烟和汽车尾气混合型污染为主。PM10和SO2超过二级标准的天数将近95%出现在采暖期。提出了可行的具体措施,指出采用以集中供热、推广使用天然气、小型锅炉改造工程和控制汽车尾气为主要措施,廉顾绿化,制定市区大气污染治理方案比较合理。 相似文献
889.
Air quality and related health effects are not only affected by policies directly addressed at air pollution but also by other environmental strategies such as climate mitigation. This study addresses how different climate policy pathways indirectly bear upon air pollution in terms of improved human health in Europe. To this end, we put in perspective mitigation costs and monetised health benefits of reducing PM2.5 (particles less than 2.5 μm in diameter) and ozone concentrations.Air quality in Europe and related health impacts were assessed using a comprehensive modelling chain, based on global and regional climate and chemistry-transport models together with a health impact assessment tool. This allows capturing both the impact of climate policy on emissions of air pollutants and the geophysical impact of climate change on air quality.Results are presented for projections at the 2050 horizon, for a set of consistent air pollution and climate policy scenarios, combined with population data from the UN's World Population Prospects, and are expressed in terms of morbidity and mortality impacts of PM2.5 and ozone pollution and their monetised damage equivalent.The analysis shows that enforcement of current European air quality policies would effectively reduce health impacts from PM2.5 in Europe even in the absence of climate policies (life years lost from the exposure to PM2.5 decrease by 78% between 2005 and 2050 in the reference scenario), while impacts for ozone depend on the ambition level of international climate policies. A move towards stringent climate policies on a global scale, in addition to limiting global warming, creates co-benefits in terms of reduced health impacts (68% decrease in life years lost from the exposure to PM2.5 and 85% decrease in premature deaths from ozone in 2050 in the mitigation scenario relative to the reference scenario) and air pollution cost savings (77%) in Europe. These co-benefits are found to offset at least 85% of the additional cost of climate policy in this region. 相似文献
890.
This paper illustrates the early results of ongoing research developing novel methods to analyse and simulate the relationship between trasport-related air pollutant concentrations and easily accessible explanatory variables. The final scope is to integrate the new models in traditional traffic management support systems for a sustainable mobility of road vehicles in urban areas.This first stage concerns the relationship between the hourly mean concentration of nitrogen dioxide (NO2) and explanatory factors reflecting the NO2 mean level one hour back, along with traffic and weather conditions. Particular attention is given to the prediction of pollution peaks, defined as exceedances of normative concentration limits. Two model frameworks are explored: the Artificial Neural Network approach and the ARIMAX model. Furthermore, the benefit of a synergic use of both models for air quality forecasting is investigated.The analysis of findings points out that the prediction of extreme concentrations is best performed by integrating the two models into an ensemble. The neural network is outperformed by the ARIMAX model in foreseeing peaks, but gives a more realistic representation of the concentration's dependency upon wind characteristics. So, the Neural Network can be exploited to highlight the involved functional forms and improve the ARIMAX model specification. In the end, the study shows that the ability to forecast exceedances of legal pollution limits can be enhanced by requiring traffic management actions when the predicted concentration exceeds a lower threshold than the normative one. 相似文献