Windsor, Ontario exposure assessment study: design and methods validation of personal, indoor, and outdoor air pollution monitoring

The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures upon asthmatic children's respiratory health was assessed. Several active and passive sampling methods were applied, or adapted, for personal, indoor, and outdoor residential monitoring of nitrogen dioxide, volatile organic compounds, particulate matter (PM; PM-2.5 pm [PM2.5] and < or =10 microm [PM10] in aerodynamic diameter), elemental carbon, ultrafine particles, ozone, air exchange rates, allergens in settled dust, and particulate-associated metals. Participants completed five consecutive days of monitoring during the winter and summer of 2005 and 2006. During 2006, in addition to undertaking the air pollution measurements, asthmatic children completed respiratory health measurements (including peak flow meter tests and exhaled breath condensate) and tracked respiratory symptoms in a diary. Extensive quality assurance and quality control steps were implemented, including the collocation of instruments at the National Air Pollution Surveillance site operated by Environment Canada and at the Michigan Department of Environmental Quality site in Allen Park, Detroit, MI. During field sampling, duplicate and blank samples were also completed and these data are reported. In total, 50 adults and 51 asthmatic children were recruited to participate, resulting in 922 participant days of data. When comparing the methods used in the study with standard reference methods, field blanks were low and bias was acceptable, with most methods being within 20% of reference methods. Duplicates were typically within less than 10% of each other, indicating that study results can be used with confidence. This paper covers study design, recruitment, methodology, time activity diary, surveys, and quality assurance and control results for the different methods used.     

多溴联苯醚分布特征及环境风险研究进展

多溴联苯醚(polybrominated diphenyl ethers,PBDEs)作为一种高效、添加型阻燃剂被广泛使用,因其具有蒸汽压低、亲脂性强、污染持久和可生物富集等特点,而成为近年来环境领域研究热点之一。在查阅近年相关文献和分析PBDEs性质的基础上,本文以PBDEs使用-环境分布-生物体内的分布-对生物毒性及机理为线索,重点总结了PBDEs在环境和尤其是在生物体内的分布情况,并分别从神经系统、甲状腺和肝脏等角度阐述了PBDEs产生毒性效应以及致毒机制的最新研究成果。在总结研究成果的基础上,提出了应逐渐重视十溴联苯醚的环境风险、电子垃圾拆解地PBDEs修复、PBDEs代谢过程以及代谢中间物的毒性等建议,以期为PBDEs相关领域研究者提供参考。     

Heavy Metal Contamination and Distribution in the Urban Environment of Guangzhou, SE China

Ever-increasing heavy metal accumulation in the urban environment of Guangzhou, the largest light industrial production base and one of the most rapidly developing cities in China, poses a serious threat to environment as well as to human health in the region. As a sink or source, urban deposits are good indicators of the level and extent of heavy metal accumulation in the surface environment. The aim of this preliminary study was to examine the distribution of heavy metal contamination in the urban environment of Guangzhou. It was based on a systematic sampling of road dusts and corresponding gully sediments along major roads running mainly through commercial and residential to industrial districts of the city. In addition to road dusts and gully sediments, ceiling dusts from the Pearl River Tunnel were also collected to characterize anthropogenic emissions dominated by traffic-related activities. In general, the level of Cd, Cu, Pb and Zn contaminations were more severe on the industrialized side of Guangzhou than on the western side where heavy traffic and industrial activities were limited. The primary determinants of the level of heavy metal contamination and the distribution of this contamination in the urban environment of Guangzhou were the site-specific conditions of its urban setting, particularly the types of industries, the nature of the traffic flow, sample residence times and variations in grain size of the particulate contaminants. This study highlights the complexity of the urban system and indicates that in just such a system individual urban components should be interlinked to assess the long-term environmental and health effects of heavy metal contamination. Among the heavy metals tested – Cd, Cu, Pb and Zn – the level of Zn contamination was the most severe and widespread, and thus requires immediate attention.     

赣东北中生代火山岩微量元素与稀土元素丰度及其演化

本文论述了赣东北中生代火山岩中微量元素与稀土元素在不同岩性岩相及时空上的分布规律:潜火山岩中Au、Ag、Cu、Pb、Zn平均含量高于火山岩,尤以中酸性岩中较高,Ⅰ,Ⅱ旋回高于其他旋回。稀土元素由Ⅰ向Ⅱ旋回,由扬子地体向华夏地体,由爆发相向溢流相、潜火山岩相,由偏基性向中酸性岩演化;稀土配分模式是“L”型,火山岩物质来源于下地壳的部分熔融。     

西安大气气相中的多环芳烃

利用PUF被动采样器于2008年8月—2009年7月采集了西安大气样品,研究了大气气相中多环芳烃（PAHs）的含量和季节分布特征。结果表明,西安大气气相中16种美国EPA优控的PAHs（Σ16PAHs）质量浓度为10.9-489.6 ng/m3（平均为143.4 ng/m3）,四季具有明显的季节差异,依次为夏季（62.5 ng/m3）〈春季（80.1 ng/m3）〈秋季（175.8 ng/m3）〈冬季（255.2 ng/m3）。气相中PAHs主要以3-4环为主,占总量的86.5%-94.1%。利用主成分分析法判断四季气相中PAHs的污染来源类型,主要为燃煤和机动车尾气及生物质燃烧的复合源。     

Application of interval 2-tuple linguistic MULTIMOORA method for health-care waste treatment technology evaluation and selection

The management of health-care waste (HCW) is a major challenge for municipalities, particularly in the cities of developing countries. Selection of the best treatment technology for HCW can be viewed as a complicated multi-criteria decision making (MCDM) problem which requires consideration of a number of alternatives and conflicting evaluation criteria. Additionally, decision makers often use different linguistic term sets to express their assessments because of their different backgrounds and preferences, some of which may be imprecise, uncertain and incomplete. In response, this paper proposes a modified MULTIMOORA method based on interval 2-tuple linguistic variables (named ITL-MULTIMOORA) for evaluating and selecting HCW treatment technologies. In particular, both subjective and objective importance coefficients of criteria are taken into consideration in the developed approach in order to conduct a more effective analysis. Finally, an empirical case study in Shanghai, the most crowded metropolis of China, is presented to demonstrate the proposed method, and results show that the proposed ITL-MULTIMOORA can solve the HCW treatment technology selection problem effectively under uncertain and incomplete information environment.     

生物炭载硫化铁对2,4-二氯苯氧乙酸的催化氧化降解

以木质生物炭为载体制备了负载型硫化铁(FeS_x/BC),采用扫描电镜/能量色散X射线光谱(SEM/EDX)、X射线粉末衍射(XRD)和X射线光电子能谱(XPS)对其结构进行了表征分析.然后将其用于催化除草剂2,4-二氯苯氧乙酸(2,4-D)的类Fenton氧化降解,并与市售硫化亚铁(c-FeS)进行对比.结果表明,生物炭可以提高硫化铁分散性,炭载催化剂中的Fe主要以Fe_3S_4形式存在.与c-FeS相比,采用FeS_x/BC催化降解2,4-D的反应速率常数(k_(obs))提高了约20倍.降解反应速率随催化剂、H_2O_2用量增加而提高,但是随初始pH(2.0—9.0)上升而下降.机理研究表明,生物炭作为电子穿梭体有助于提高·OH的生成量,促进2,4-D降解中间产物转化、并使脱氯反应更完全.     

轴入式旋风子气粒分离特性的数值模拟与试验

对轴入式旋风子通过数值模拟和试验测试分析其阻力性能与效率性能.将气体相作为连续介质,采用κ-ε湍流模型,对流场进行数值模拟;将颗粒相作为离散体系,采用随机轨道模型,根据已算出的流场来计算颗粒轨道,分析其阻力与效率性能.计算时选用不同粒径的颗粒相进行模拟,从而得到不同工况下的阻力性能与效率性能.试验测试时,通过改变风速,测定不同风速下多管旋风的阻力损失以及额定流量下的除尘效率.并对模拟结果与试验作比较分析,阐明了利用数值模拟在工程设计实施前或产品生产(改造)前预测方案的实际效果与产品性能的可行性.     

中国城市公园灰尘的重金属空间分布特征及其影响因素

通过收集公开发表的中国城市公园灰尘重金属数据,分析公园灰尘中Cr、Cu、Zn、Pd、Ni和Cd等6种元素的空间分布特征及富集状况,并对其影响因素进行了探讨.结果 表明,Cr、Cu、Zn、Cd等4种重金属含量的空间分布具有相似性,东部地区为高值区,东北地区和西北地区为低值区;Pb和Ni具有相似的空间分布特征,东部和中部地...     

平原河网区河流连通性评价研究

河流连通性对流域水文过程特征、水环境条件以及河湖蓄泄能力等有较大影响。平原河网地区是河流高度发育并受到城市化等人类活动深刻影响的区域,并且区域内水系结构破坏、河流连通受阻已成为洪涝灾害频发的重要原因之一。为此通过对现有的河流连通评价方法的分析,尝试建立基于水流阻力与水文过程的平原河网河流连通性评价方法,并以鄞东南平原河网为例开展了应用分析,结果表明2010年的河流连通性比1990年的明显减小。同时,通过对比分析几种河流连通性评价方法可以看出,基于水流阻力与水文过程的河流连通性评价方法能较好的评价平原河网区河流连通性,评价结果优于其他方法计算结果,更符合实际情况,可为平原河网区河流连通性定量评价提供参考