GIS-based analysis of population exposure to PM2.5 air pollution—A case study of Beijing

PM_(2.5), formally defined as particulate matter with diameter less than 2.5 μm, is one of most harmful air pollutants threatening human health. Numerous epidemiological studies have shown that both short-term and long-term exposures to PM_(2.5) are strongly linked with respiratory diseases. In this study, various types of spatio-temporal data were collected and used to estimate the spatio-temporal variation of PM_(2.5) exposure in Beijing in 2014. The seasonal and daily variation of the population-weighted exposure level(PWEL) in 2014 was estimated and compared. The results show that the population exposure to ambient air pollution differs significantly in the four seasons, and the exposure levels in winter and spring are notably higher than the other seasons; the exposure level changes greatly from North to South, and each sub-district maintains similarity to neighboring sub-districts.     

From illite/smectite clay to mesoporous silicate adsorbent for efficient removal of chlortetracycline from water

A series of mesoporous silicate adsorbents with superior adsorption performance for hazardous chlortetracycline(CTC) were sucessfully prepared via a facile one-pot hydrothermal reaction using low-cost illite/smectite(IS) clay,sodium silicate and magnesium sulfate as the starting materials.In this process,IS clay was "teared up" and then "rebuilt" as new porous silicate adsorbent with high specific surface area of 363.52 m~2/g(about 8.7 folds higher than that of IS clay) and very negative Zeta potential(- 34.5 mV).The inert Si- O- Si(Mg,Al) bonds in crystal framework of IS were broken to form Si(Al)- O~- groups with good adsorption activity,which greatly increased the adsorption sites served for holding much CTC molecules.Systematic evaluation on adsorption properties reveals the optimal silicate adsorbent can adsorb 408.81 mg/g of CTC(only 159.7 mg/g for raw IS clay) and remove 99.3%(only 46.5%for raw IS clay) of CTC from 100 mg/L initial solution(pH 3.51;adsorption temperature 30℃;adsorbent dosage,3 g/L).The adsorption behaviors of CTC onto the adsorbent follows the Langmuir isotherm model,Temkin equation and pseudo second-order kinetic model.The mesopore adsorption,electrostatic attraction and chemical association mainly contribute to the enhanced adsorption properties.As a whole,the high-efficient silicate adsorbent could be candidates to remove CTC from the wastewater with high amounts of CTC.     

2015年国庆期间我国城市空气污染特征及成因分析

本文基于我国31个省会城市283个环境监测站的实时观测数据,分析了2015年国庆期间我国城市空气污染特征,并结合MODIS/Terra数据、欧洲中期天气预报中心(ECMWF)气压场及风场数据对其成因进行了讨论。结果表明:本次区域性空气污染最先出现在华中和华东地区,但是在华北地区最为严重。不同城市的主要污染物具有显著的时空差异。除西安和乌鲁木齐以外,其他城市的颗粒物污染主要由细颗粒物主导。NO_2、CO和SO_2的变化趋势基本一致,而O_3仅在北京、天津和济南三个城市与其他污染气体同步变化;在其他城市则与NO_2和CO等呈现相反的变化趋势。由卫星影像、天气形势和风场变化分析得知:不考虑本地背景排放源的前提下,本次污染事件主要由我国秋季的秸秆燃烧和不利的气象条件共同作用造成的。     

烟气对民航安全的评估技术研究

工业设施排放的烟气对民航具有潜在影响,开展烟气对民航影响方面的研究,对维护机场净空安全具有重要意义.结合国内外烟气对民航安全评估的相关研究现状,归纳了烟气自身及其排放源的特点.确定烟气主要影响机场附近航行安全,同时烟气排放源可视为一般障碍物,并从烟气流和烟气成分角度分析烟气自身对航行安全的影响.最后对实测、软件仿真、风洞试验等现有评估方法进行了对比分析,归纳了烟气评估技术现实情况,并展望了评估技术未来的发展趋势.     

深圳市一次典型污染天气污染特征分析研究——以2016年3月空气质量为例

2016年3月31日,深圳市及其周边地区出现典型的区域性空气污染事件,多数地区的AQI超过了100.主要污染物浓度和气象要素的逐小时变化表明,该次污染天气主要是在不利气象条件下,由污染物区域传输和二次污染物生成共同导致的.进一步的后向轨迹分析表明,污染日抵达深圳市的气团可能从东莞、广州和佛山等地区携带了大量污染物,并且移动速度缓慢,造成了深圳较为严重的污染天气,而污染日前和污染日后抵达深圳市的气团有利于污染物的稀释扩散,因此空气质量较好.     

热活化过硫酸盐氧化降解水溶液中的抗生素卡巴多司和奥喹多司

硫酸根自由基(SO■)高级氧化技术(SR-AOPs)是一种新型的原位化学氧化技术(ISCO),在水处理领域具有广阔的应用前景,可用于治理土壤和地下水中抗生素污染.本研究采用热活化过硫酸盐(PS)产生SO■,考察其对水溶液中抗生素卡巴多司(CBX)和奥喹多司(OQX)的降解效果,评估操作参数和水质成分对CBX降解的影响,并对CBX的降解产物进行鉴定.结果表明,与OQX相比,CBX更容易被热活化PS工艺氧化降解,这可能是因为CBX含有富电子的腙支链,而OQX含有惰性的酰胺支链.升高温度、增加PS浓度和降低溶液pH值均可显著促进CBX的降解.HCO~-_3的存在对CBX降解有促进作用,可能是由于生成的碳酸根自由基(CO■)参与了反应.Suwannee河富里酸(SRFA)具有双重影响,低浓度时促进CBX降解,而高浓度时呈现抑制作用.NO~-_3的存在对CBX的降解没有明显影响,而NO~-_2的存在可以显著抑制其降解.CBX在天然地表水中的降解效率低于在地下水中的效率,可能与不同水质中天然有机质的含量有关.产物鉴定表明,热活化PS氧化降解CBX生成了羟基化、脱氧和支链断裂产物,表明氧化反应主要改变了CBX分子中的腙支链和N—O结构.研究表明,热活化PS工艺可有效降解水溶液中的CBX和OQX,但在该技术实际应用时应充分评估天然水质成分的影响.     

纺织品防微波辐射检测方法及其仪器的研究

根据对纺织品微波性能测试方法的系统研究,针对我国纺织品防辐射检测现状和科技发展的需求,运用系统分析、有效控制方法,采用先进技术,开发完成了我国首台自行设计、自行制造,适于2,250～2,650MHz范围织物防微波辐射现代快速检测仪器。经以中国工程院院士姚穆为首的技术审定委员会审定认为:该仪器设计科学合理、结构严谨、检测快速、数据准确,关键技术达到国际先进水平。     

昆明市东川区农业旱灾风险区识别研究

昆明市东川区是云南省农业旱灾危害较为严重的区域之一。利用2000-2007年东川区各乡镇历史灾情等数据资料,应用风险分析理论、效用理论、因子-成份分析方法等理论方法,在分别研究致灾风险度、承灾体易损性及地域人群对农业旱灾心理反响等基础上,构建了东川区农业旱灾风险评价模型。初步揭示出东川区农业旱灾风险度呈现出自南向北、自西向东逐渐增强的空间态势;识别出极高风险区、高风险区、中风险区和低风险区等4个农业旱灾风险区;发现东川区各地农业旱灾综合风险度、致灾风险度、承灾体易损度以及地域人群对旱灾的心理响应值等指数之间普遍存在着明显的正相关。     

士耳其和法国的巨灾保险制度

土耳其和法国都建立起了政府支持的巨灾保险制度,但由于其各自面临的自然灾害风险特征、国内保险市场的发展状况、政治法律体制等大相径庭,决定了两国的巨灾保险不论从具体的制度要素还是运营模式来看,都存在很大差异。     

Quantitative assessment of polycyclic aromatic hydrocarbons in sewage sludge from wastewater treatment plants in Qingdao, China

In this study, 16 polycyclic aromatic hydrocarbons (PAHs) were detected in sewage sludge samples from four wastewater treatment plants (WWTPs) in Qingdao, China. These WWTPs differ in the type of treatment used and in the origin of the wastewater. The total amounts of PAHs in digested sludges ranged from 1.9645 to 6.5752 mg/kg, which did not exceed the projected European Union cut-off limits (6 mg/kg) for sludge found in farmland, except for the Haibohe WWTP. Significant differences were observed in overall PAH values between WWTPs receiving domestic effluents and those receiving industrial effluents. The total amounts of PAHs in digested sludge from the Licunhe and Haibohe WWTPs, which mainly received industrial effluents, were markedly higher than those of the Tuandao and Huangdao WWTPs, which received only domestic effluents. The distribution of PAH compounds in digested sludges were analysed. At the Tuandao, Huangdao and Licunhe WWTPs, 2-, 3-, 4-benzene rings were predominant, accounting for 100%, 99.8% and 99.0% of the sum concentration of 16 PAHs (∑PAHs), respectively. At the Haibohe WWTP, a large number of high molecular weight PAHs (5-, 6-benzene rings) were observed, accounting for 30% of the ∑PAHs. The sum of seven carcinogenic PAHs (∑PAHs-c) ranged from 0.8694 to 3.0389 mg/kg in four WWTPs. The highest value was found in the Haibohe WWTP. Moreover, the PAH concentrations in sludges from the different treatment processes in the Licunhe and Tuandao WWTPs are discussed.