Source apportionment of PAHs and n-alkanes bound to PM1 collected near the Venice highway

n-Alkanes and polycyclic aromatic hydrocarbons (PAHs) bound to atmospheric particulate matter (PM₁) were investigated in a traffic site located in an urban area of Venice Province (Eastern Po Valley, Italy) during the cold season. Considering the critical situation affecting the Veneto Region concerning the atmospheric pollution and the general lack of information on PM₁ composition and emission in this area, this experimental study aims at determining the source profile, their relative contributions and the dispersion of finer particles. Four sources were identified and quantified using the Positive Matrix Factorization receptor model: (1) mixed combustions related to the residential activities, (2) agricultural biomass burning in addition to the resuspension of anthropogenic and natural debris carried by the wind, (3) gasoline and (4) diesel traffic-related combustions. The role of local atmospheric circulation was also investigated to identify the pollutant sources.     

Influence of agricultural activities, forest fires and agro-industries on air quality in Thailand

Annual and monthly-based emission inventories in northern, central and north-eastern provinces in Thailand, where agriculture and related agro-industries are very intensive, were estimated to evaluate the contribution of agricultural activity, including crop residue burning, forest fires and related agro-industries on air quality monitored in corresponding provinces. The monthly-based emission inventories of air pollutants, or, particulate matter (PM), NOx and SO₂, for various agricultural crops were estimated based on information on the level of production of typical crops: rice, corn, sugarcane, cassava, soybeans and potatoes using emission factors and other parameters related to country-specific values taking into account crop type and the local residue burning period. The estimated monthly emission inventory was compared with air monitoring data obtained at monitoring stations operated by the Pollution Control Department, Thailand (PCD) for validating the estimated emission inventory. The agro-industry that has the greatest impact on the regions being evaluated, is the sugar processing industry, which uses sugarcane as a raw material and its residue as fuel for the boiler. The backward trajectory analysis of the air mass arriving at the PCD station was calculated to confirm this influence. For the provinces being evaluated which are located in the upper northern, lower northern and northeast in Thailand, agricultural activities and forest fires were shown to be closely correlated to the ambient PM concentration while their contribution to the production of gaseous pollutants is much less.     

燃煤、燃气锅炉综合效益模糊评价及分析结果——以乌鲁木齐市集中供热锅炉为例

以乌鲁木齐市某集中供热站锅炉节能减排方案为例,通过建立供热锅炉实施方案综合评价指标体系,运用层次分析法确定方案各项指标权重,利用模糊综合评判法分别从锅炉燃煤、燃气情况下的环境效益、经济效益以及设施能耗、物耗等指标着手,进行综合评价,并对集中供热锅炉燃煤与燃气方案综合评判结果进行分析,最终评选出较优实施方案。评选结果表明:燃气方案综合效益较好,可有效实现节能减排,为今后燃气锅炉建设提供一定的参考作用。     

污泥焚烧中二氧化硫检测新方法及污泥处理探讨

对新乡市9个污水处理场污泥预处理后,用测硫仪分析污泥含硫量,并用经验公式根据年污水处理量,估算焚烧污泥方法年二氧化硫排放总量。结果显示：用测硫仪测定污泥含硫量,核算二氧化硫排放量,与现有方法相比,操作简便易行,结果不受采样条件、时间、环境、布点等因素影响,重现性好、完整、精密。同时发现部分污泥含硫量超过规定用煤中含硫量,建议用焚烧方法处置污泥,净化尾气。     

春节期间南京市大气气溶胶粒径分布特征

为研究春节期间燃放烟花爆竹对城市大气气溶胶数浓度粒径谱分布的影响,对2012年1月19~31日南京大气气溶胶数浓度、污染气体浓度和质量浓度进行了观测分析.结果表明,烟花爆竹的燃放期间10~20 nm气溶胶浓度远低于非燃放期,50~100、100~200和200~500 nm数浓度有较大增加,20~50 nm和0.5~10μm气溶胶数浓度变化不大.烟花爆竹的燃放对气溶胶数浓度谱影响较大,非燃放期数浓度谱为双峰型分布;在燃放期数浓度谱为单峰性分布,且峰值向大粒径段偏移.烟花爆竹燃放期间质量浓度谱为双峰型分布,对细粒子的质量浓度影响较大,燃放期间PM2.5/PM10和PM1.0/PM10的值可升高10%.烟花爆竹的大量燃放对1.0~2.1μm粒径段气溶胶密度影响最大,对其他粒径段密度影响较小.     

Images of war: using satellite images for human rights monitoring in Turkish Kurdistan

In areas of war and armed conflict it is difficult to get trustworthy and coherent information. Civil society and human rights groups often face problems of dealing with fragmented witness reports, disinformation of war propaganda, and difficult direct access to these areas. Turkish Kurdistan was used as a case study of armed conflict to evaluate the potential use of satellite images for verification of witness reports collected by human rights groups. The Turkish army was reported to be burning forests, fields and villages as a strategy in the conflict against guerrilla uprising. This paper concludes that satellite images are useful to validate witness reports of forest fires. Even though the use of this technology for human rights groups will depend on some feasibility factors such as prices, access and expertise, the images proved to be key for analysis of spatial aspects of conflict and valuable for reconstructing a more trustworthy picture.     

Identifying and modeling key trade-offs between hydrogen fuel cell and electric vehicles

Through a sensitivity analysis, the trade-off between vehicle range and CO₂ emissions is investigated as a function of electric emissions coefficient. Various powertrains were analysed for use in a small crossover sport utility vehicle. Gasoline, gasoline electric hybrid, diesel, fuel cell and battery electric vehicles (BEVs) were considered. Using various upstream fuel pathways and a model for vehicle performance, emissions and energy use were estimated. The hydrogen fuel cell vehicle was found preferable to BEVs under conditions of high CO₂ emissions per kW-hr and a high vehicle range requirement. The BEV was preferable for all other conditions.     

高效喷淋泡沫脱硫技术及装置的应用

SO2是产生酸雨的主要气体,其主要来源于工业燃煤锅炉.以沈阳一家电厂为例,该厂选用新型高效的喷淋泡沫脱硫除尘器对锅炉排放的SO2进行治理.进入喷淋泡沫塔前的SO2平均浓度为2780 mg/m3,经脱硫后出塔平均浓度为289.3 mg/m3,去除率为89.6%.结果表明,这种有别于传统湿法的新型高效的喷淋泡沫脱硫技术及装置具有脱硫效率高、装置占地少、运行稳定、沉淀物易于回收利用等特点,对锅炉排放的SO2进行治理是非常有效的.     

Implications of high altitude desert dust transport from Western Sahara to Nile Delta during biomass burning season

The air over major cities and rural regions of the Nile Delta is highly polluted during autumn which is the biomass burning season, locally known as black cloud. Previous studies have attributed the increased pollution levels during the black cloud season to the biomass or open burning of agricultural waste, vehicular, industrial emissions, and secondary aerosols. However, new multi-sensor observations (column and vertical profiles) from satellites, dust transport models and associated meteorology present a different picture of the autumn pollution. Here we show, for the first time, the evidence of long range transport of dust at high altitude (2.5-6 km) from Western Sahara and its deposition over the Nile Delta region unlike current Models. The desert dust is found to be a major contributor to the local air quality which was previously considered to be due to pollution from biomass burning enhanced by the dominant northerly winds coming from Europe.     

Impact of anthropogenic emissions and open biomass burning on regional carbonaceous aerosols in South China

Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC = 8.7 ± 4.5 μg/m³, EC = 2.5 ± 1.9 μg/m³) among the three sites, and Jianfeng Mountains in Hainan Island (OC = 5.8 ± 2.6 μg/m³, EC = 0.8 ± 0.4 μg/m³) and Tengchong mountain over the east edge of the Tibetan Plateau (OC = 4.8 ± 4.0 μg/m³, EC = 0.5 ± 0.4 μg/m³) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.