银川市臭氧污染特征及影响因素分析

依据2014年银川市6个自动空气监测子站的监测数据,分析银川市臭氧浓度的污染特征,并对夏季臭氧相关气象因子进行分析。结果表明,从监测点位来看,银湖巷站点臭氧浓度最高,宁安大街次之,宁化生活区臭氧浓度最低。从时间变化规律来看,银川市臭氧浓度呈夏季最高,春季次之,秋季、冬季污染较低,其中臭氧月均浓度最大值出现在5月、6月。臭氧日变化呈单峰变化规律,夜间臭氧浓度较低,白天臭氧浓度较高。夏季臭氧浓度与二氧化氮、相对湿度呈显著的负相关性,与气温、风速呈显著正相关性。     

Variation of airborne quartz in air of Beijing during the Asia-Pacific Economic Cooperation Economic Leaders' Meeting

Quartz particles are a toxic component of airborne paniculate matter(PM).Quartz concentrations were analyzed by X-ray diffraction in eighty-seven airborne PM samples collected from three locations in Beijing before,during,and after the Asia-Pacific Economic Cooperation(APEC) Leaders' Meeting in 2014.The results showed that the mean concentrations of quartz in PM samples from the two urban sites were considerably higher than those from the rural site.The quartz concentrations in samples collected after the APEC meeting,when the pollution restriction lever was lifted,were higher than those in the samples collected before or during the APEC meeting.The quartz concentrations ranged from 0.97 to 13.2 μg/m~3,which were among the highest values amid those reported from other countries.The highest quartz concentration exceeded the Californian Office of Environmental Health Hazard Assessment reference exposure level and was close to the occupational threshold limit values for occupational settings.Moreover,a correlation analysis showed that quartz concentrations were positively correlated with concentrations of pollution parameters PM_(10),PM_(2.5),SO_2 and NO_x,but were negatively correlated with O_3 concentration.The results suggest that the airborne quartz particles may potentially pose health risks to the general population of Beijing.     

Mediating an invisible policy problem: Nottingham’s rejection of congestion charging

ABSTRACT

This paper presents a qualitative case study of community participation in local air quality management in Nottingham (UK). We analyse Nottingham’s response to a “clean air zone” mandate: despite national government and local community support of this congestion charging policy, the City Council rejected the measure. We focus on the policy framing, with data from policy documents, interviews with government and non-government actors, and observation in local activities. We found that community groups build links with local government in two ways: (1) as a coalition against the national government and austerity measures, and (2) as “neutral”, non-expert communicators of air pollution as an “invisible” policy problem. We show how this invisibility plays a significant role in factors such as trust, risk, responsibility, and policy communication. This research has theoretical implications for the communication of air pollution and practical implications for cities looking to implement similar transport-oriented strategies.     

THE HUDSON BAY AIR MASS TYPE–SOME CLIMATOLOGICAL IMPLICATIONS

A substantial percentage of days with below normal temperatures in central Illinois during May and June (1956-1965) appear to be associated with polar air masses which traverse the Hudson Bay area before entering the Midwest. January departures, in contrast, are related to polar air masses that enter the United States near the Mackenzie River in western Canada. The general influences of the Hudson Bay area on climate are discussed.     

Mutagenic properties of PM2.5 air pollution in the Padana Plain (Italy) before and in the course of XX Winter Olympic Games of "Torino 2006"

PM2.5 is one of the most important aspects of environmental health. This air pollutant is breathable and it is implicated in several chronic adverse health effects such as the decrease of respiratory functionality and cancer. Several in vitro bioassays are able to predict the mutagenic/carcinogenic activity of the environmental pollutants and mixtures of them. In this study PM2.5 air pollution was daily monitored in three cities located in the Northern part of Italy and the mutagenic properties of the PM2.5 organic extracts were also assessed. Samplings lasted 14 months and cover the period of the Winter Olympic Games of "Torino 2006". In this work, the levels of PM2.5, its mutagenic properties (detected with Salmonella typhimurium assay), the role of the Olympic Games as environmental factor and some meteorological data are discussed. The mean concentration of PM2.5 measured in Torino was 45.4 (+/-30.6) microg/m(3), in Pavia 37.6 (+/-25.6) microg/m(3), in Verona 43.1 (+/-28.5) microg/m(3). Findings of the monthly pool bioassay were in Torino 107 (+/-104) net revertans/m(3), in Pavia 108 (+/-89) net revertans/m(3), in Verona 128 (+/-109) net revertans/m(3). The Olympic Games period data show that PM2.5 pollution and its load of mutagenic potential are different and partially independent phenomena. The Olympic Games had not a great impact on the PM2.5 pollution. The exclusive PM2.5 gravimetric analysis shows a potential human risk if compared with the latest international guide values but it does not describe exhaustively the human health risk associated to the presence of this particular air pollutant. Moreover, the chemical and biological activity qualification of the PM organic extracts as a whole, can instead improve the knowledge.     

An online air pollution forecasting system using neural networks

In this work, an online air pollution forecasting system for Greater Istanbul Area is developed. The system predicts three air pollution indicator (SO(2), PM(10) and CO) levels for the next three days (+1, +2, and +3 days) using neural networks. AirPolTool, a user-friendly website (http://airpol.fatih.edu.tr), publishes +1, +2, and +3 days predictions of air pollutants updated twice a day. Experiments presented in this paper show that quite accurate predictions of air pollutant indicator levels are possible with a simple neural network. It is shown that further optimizations of the model can be achieved using different input parameters and different experimental setups. Firstly, +1, +2, and +3 days' pollution levels are predicted independently using same training data, then +2 and +3 days are predicted cumulatively using previously days predicted values. Better prediction results are obtained in the cumulative method. Secondly, the size of training data base used in the model is optimized. The best modeling performance with minimum error rate is achieved using 3-15 past days in the training data set. Finally, the effect of the day of week as an input parameter is investigated. Better forecasts with higher accuracy are observed using the day of week as an input parameter.     

铁岭市空气日报及预报的相关性研究

本文采用了空气污染指数进行评价空气质量,确定铁岭市空气质量日报、预报。根据空气污染指数值确定空气质量污染程度,最后采用数据统计方法对日报、预报的结果进行检验,检查两个样本均值之间是否有显著性差异。     

沈阳市室内空气中挥发性有机物的污染状态分析

选取装修时间分别为7d、30d、90d的居室各50户,采集室内空气样测定总挥发性有机物（TVOC）浓度,发现超标率随装修时间的延长而下降,且90d后TVOC超标2倍以上的严重污染户已降至2％;装修3个月以上居室室内空气中TVOC组分共检测出59种,其中32种为半数以上居室所共有,经分析绝大多数为室内装修材料所释放且多为有害物质;通过实验发现周期性通风放置比封闭状态放置能够更快地降低室内TVOC浓度．是减轻TVOC污染的最佳方法。     

沈阳市环境空气质量近10年变化趋势与污染控制对策

论述了近10年沈阳市环境空气质量变化趋势,对环境空气质量进行了空气综合污染指数评价和Spearman秩相关检验评价,并详细地阐明了环境空气污染与全市的能源结构、污染源排放状况和气候、气象条件等因素密切相关,提出解决环境空气污染的控制对策。     

考虑道路扬尘特性的环境空气质量在线监测方法

为判断环境空气污染的程度,提出一种考虑道路扬尘特性的环境空气质量在线监测方法。通过前端数据监测模块采集大气环境数据,基于光全散射法监测道路扬尘的质量浓度和密度;通过监测通信模块将监测结果传送至云服务器;云服务器利用基于极限学习机神经网络的预测模型,采用自适应粒子群优化算法,获取最佳的环境空气质量在线监测结果。结果表明,该方法学习速率的取值为0.5时,能够完成颗粒物浓度和密度的准确检测,且解释方差<2%,同时能够监测扬尘颗粒的扩散时间,确定适合活动的区域。