被动加标在水生生态风险评价中的应用——以多氯联苯分配系数的测定为例

准确的水生生态风险评价需要可靠的毒性数据,而其获取要求在一定时间范围内,水体中污染物的浓度保持恒定。对疏水性有机污染物进行水体生物毒性测试时,通常采用有机溶剂加标,然而该方式可能因为污染物的挥发和降解、容器壁吸附、生物摄取等问题,水体中污染物浓度持续下降,导致污染物的浓度-效应关系难以明确。近期为了克服这些问题,被动加标用于替代溶剂加标,通过污染物在加标体系中平衡分配来维持精确和恒定的水体浓度,同时还可通过测定加标聚合物中污染物的浓度来监测水体浓度。首先介绍了被动加标方法及其材料选择,讨论了该方法在生态风险评价中的主要应用,包括分配系数的测定、体外细胞测试、体内生物积累及毒性测试,以及沉积物毒性评价等。然后,以测定代表污染物多氯联苯在聚二甲基硅氧烷与水间的分配系数为例,详细说明被动加标的操作流程。最后,讨论了被动加标方法的优缺点,并对其在水生生态风险中的应用前景进行了展望。     

室内空气中的气态多环芳烃的被动采样监测

利用自制被动采样装置,在2011年秋冬季对南京市部分地区室内空气中5种气态多环芳烃(PAHs)(萘、苊烯、苊、芴、菲)进行了为期100d的连续采样检测,被动采样器的采样速率为0.012m3/d,5种PAHs的回收率在63%～105%之间,方法检出限在1.1～2.4ng范围内。结果表明,南京市5处不同室内环境空气中萘的浓度最高,占总量的90%以上。室内环境空气中5种PAHs的总浓度为230～1564ng/m3。住宅内人体对5种PAHs的暴露速率为479～560ng/h。     

巢湖沉积物有效磷的原位高分辨分析研究

将两种原位被动采样技术——高分辨平衡式间隙水(HR-Peeper)与氧化锆薄膜梯度扩散技术(Zr-oxide DGT)相结合,分别对巢湖西半湖7个点位溶解态反应性磷(cPW)和有效磷(cDGT)进行原位测定分析,cPW和cDGT在大部分沉积物剖面的分布相似或局部相似,说明不同深度沉积物固相有效磷组分对间隙水SRP的缓冲能力较接近.利用界面扩散通量和cDGT/cPW比值(R)表征沉积物磷的活性,从巢湖湖心向南淝河入湖口方向,界面以下6 mm的cPW、cDGT和扩散通量的变化基本一致,均呈递增趋势,表明沉积物磷的污染水平在增加;R值变化较小,说明沉积物界面处的缓冲能力差异不明显.     

MR阻尼器的简化参数模型及其应用

MR阻尼器应用于控制风振、地震等引起的随机振动时需用参数化表达式来描述MR阻尼器简化的力学模型 ,从而更好地揭示MR阻尼器的减振机理。本文采用偏最小二乘法误差估计、Chebyshev多项式拟合建立了MR阻尼器简化模型的参数化表达式 ,并应用于斜拉索振动控制中 ,为合理选择MR阻尼器提供了便捷、可靠的手段     

珠江三角洲地区大气中有机氯农药的被动采样观测

利用PUF被动采样装置,对珠江三角洲地区大气中有机氯农药(OCPs)进行监测.结果显示,广东省大气中有机氯农药主要是滴滴涕(DDTs)、六六六(HCH)及氯丹(Chlordane),其中DDTs约占总OCPs的54.5%;香港大气中农药残留主要是氯丹和DDTs,氯丹约占总含量的51.3%.珠三角地区大气中有机氯农药空间分布差异明显(580-5500pg·m-3),香港平均浓度远远低于广东省.另外,广东省仍有工业DDT在使用,造成广东省大气中有"新"的工业DDT输入;而三氯杀螨醇是香港大气中DDT高含量的重要来源;广东省和香港HCH主要源于林丹使用的残留,香港的Eastern及Tsuen Wan源于工业六六六使用的残留;珠江三角洲所有采样点的HCB含量较低,大气中HCB少量残留可能是HCB作为药物中间体的化学合成及HCB在大气中长距离传输的结果.     

Passive water sampling for polynuclear aromatic hydrocarbons using lipidcontaining semipermeable membrane devices (SPMDs): Application to contaminant residence times

Lipid-containing semipermeable membrane devices are applied to the quantitative determination of the persistence of polynuclear aromatic hydrocarbons (PAH) in an irrigation water canal, a representative waterway. The uniform and reproducible sampling of the USGS design of lipid-containing SPMDs is exploited to measure PAH half-lives without requiring calculation of water concentrations. The trend in calculated PAH half-lives agrees with that expected if volatilization is a significant mechanism for loss from the canal with more volatile PAHs having shorter half-lives. The higher persistence of phenanthrene compared to anthracene is consistent with the greater stability of phenanthrene and suggests, with other physicochemical evidence, that other (reactive) mechanisms may be involved. The results of this study demonstrate the feasibility of the SPMD method for the measurement of residence times in aquatic and other compartments. Such information is essential for quantifying contaminant behavior in the environment and providing insights into contaminant fate.     

吸烟及吸二手烟对人体多环芳烃内暴露的影响

采用快速液相色谱-三重四级杆串联质谱仪对吸烟、吸二手烟和不吸烟的居民的尿样进行抽检,分析了10种多环芳烃羟基代谢物(OH-PAHs)的组成和含量,评估了吸烟及吸二手烟对人体OH-PAHs内暴露水平的影响.结果表明,吸烟及吸二手烟对居民尿液中OH-PAHs的浓度水平和组成特征均有影响,对萘和芴的代谢产物影响最为显著.OH-PAHs的浓度水平按照吸烟组>吸二手烟组>不吸烟组的顺序递减,吸烟组和吸二手烟组人群尿液中萘的代谢产物2-羟基萘和1-羟基萘所占的比例分别是不吸烟组人群的1.5、1.2倍和1.7、1.9倍;吸烟、吸二手烟和不吸烟人群体内各OH-PAHs之间的相关性分析表明,吸二手烟人群体内OH-PAHs来源最为复杂,受环境空气和香烟烟雾的双重影响.与同类研究结果相比,本研究吸二手烟人群体内OH-PAHs明显偏低,这可能与吸二手烟人群受到烟气的暴露时间和暴露量有关.     

Acoustically detected year-round presence of right whales in an urbanized migration corridor

Species' conservation relies on understanding their seasonal habitats and migration routes. North Atlantic right whales (Eubalaena glacialis), listed as endangered under the U.S. Endangered Species Act, migrate from the southeastern U.S. coast to Cape Cod Bay, Massachusetts, a federally designated critical habitat, from February through May to feed. The whales then continue north across the Gulf of Maine to northern waters (e.g., Bay of Fundy). To enter Cape Cod Bay, right whales must traverse an area of dense shipping and fishing activity in Massachusetts Bay, where there are no mandatory regulations for the protection of right whales or management of their habitat. We used passive acoustic recordings of right whales collected in Massachusetts Bay from May 2007 through October 2010 to determine the annual spatial and temporal distribution of the whales and their calling activity. We detected right whales in the bay throughout the year, in contrast to results from visual surveys. Right whales were detected on at least 24% of days in each month, with the exception of June 2007, in which there were no detections. Averaged over all years, right whale calls were most abundant from February through May. During this period, calls were most frequent between 17:00 and 20:00 local time; no diel pattern was apparent in other months. The spatial distribution of the approximate locations of calling whales suggests they may use Massachusetts Bay as a conduit to Cape Cod Bay in the spring and as they move between the Gulf of Maine and waters to the south in September through December. Although it is unclear how dependent right whales are on the bay, the discovery of their widespread presence in Massachusetts Bay throughout the year suggests this region may need to be managed to reduce the probability of collisions with ships and entanglement in fishing gear.     

外部安防系统在海洋石油固定平台中的应用

为了弥补传统的海洋石油固定平台内部安防系统的不足,达到海洋石油固定平台全天候自动监测、自动报警、无人值守、主动防御、预防为主的目的,以便提早发现灾害或事故的苗头,提供及时报警,并采取适当的预防措施。根据主动防御、准确测报、防范未然和规避事故的原则方针,按区域警戒与要地防范相结合的方法,介绍了外部安防系统在海洋石油固定平台中的应用,包括六个子系统、工作流程、各个子系统在海洋石油固定平台中的应用以及特点和价值,从监控、应急、监管等多角度出发,实现了一体化的安全监控。     

室内不同燃烧模式香烟污染的研究

香烟燃烧的主动吸烟、呼出烟雾、自由燃烧3种排放方式中,对一氧化碳CO、总挥发性有机物TVOC进行测定分析。自由燃烧模式较主动吸烟模式造成的CO和TVOC污染更高。对于室内环境的污染和被动吸烟者的危害,自由燃烧模式与呼出烟气模式的贡献比例CO和TVOC分别约为15/1和4/1。主动吸烟者吸入的烟气中CO和TVOC浓度可分别高达约10000mg/m3和800mg/m3,高出国家室内空气环境标准限量约1000倍,吸入的烟气中约有40%的CO通过肺部被人体吸收。