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11.
A study of ether-linked moieties in macromolecular bound residues of polycyclic aromatic hydrocarbons (PAH) generated in bioremediation experiments was performed using high temperature hydrolysis degradation with subsequent analysis of the products by GC-MS. This hydrolysis reaction was specifically designed to cleave ether bonds including relatively stable diarylether structures. Among the reaction products, aromatic alcohols representing typical microbiologically derived metabolites of PAH were found in addition to natural compounds. Thus, parts of the bound residues appeared to be linked within the macromolecular material by ether bonds. Model experiments with an oxidoreductase enzyme and aromatic alcohols indicate the formation of these ether bonds to be an enzyme-catalysed process.  相似文献   
12.
2003年“雪龙号”北极科学考察期间,对沿途海洋大气进行采样,分析其中气相多环芳烃的空间分布。结果显示,气相中主要是2-4环的多环芳烃,其中菲为主要的化合物,平均占到总多环芳烃的55.1%。在整个航程的广泛区域尺度内,气相总多环芳烃浓度在1043.9-92993.1pg/m3。空间分布上,远东亚的海面>北太平洋海面>北极圈以内海面;总多环芳烃的浓度随纬度升高呈现显著降低的趋势。通过Clausius-Clapeyron方程对浓度和温度相互关系的分析表明,温度是控制气相多环芳烃长距离传输的主要因素。  相似文献   
13.
Amount and composition of dissolved organic matter (DOM) were evaluated for multiple, nested stream locations in a forested watershed to investigate the role of hydrologic flow paths, wetlands and drainage scale. Sampling was performed over a 4‐year period (2008–2011) for five locations with drainage areas of 0.62, 3.5, 4.5, 12 and 79 ha. Hydrologic flow paths were characterized using an end‐member mixing model. DOM composition was determined using a suite of spectrofluorometric indices and a site‐specific parallel factor analysis model. Dissolved organic carbon (DOC), humic‐like DOM and fluorescence index were most sensitive to changes with drainage scale, whereas dissolved organic nitrogen, specific UV absorbance, Sr and protein‐like DOM were least sensitive. DOM concentrations and humic‐like DOM constituents were highest during both baseflow and stormflow for a 3.5‐ha catchment with a wetland near the catchment outlet. Whereas storm‐event concentrations of DOC and humic DOM constituents declined, the mass exports of DOC increased with increasing catchment scale. A pronounced dilution in storm‐event DOC concentration was observed at peak stream discharge for the 12‐ha drainage location, which was not as apparent at the 79‐ha scale, suggesting key differences in supply and transport of DOM. Our observations indicate that hydrologic flow paths, especially during storms, and the location and extent of wetlands in the catchment are key determinants of DOM concentration and composition. This study furthers our understanding of changes in DOM with drainage scale and the controls on DOM in headwater, forested catchments. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
14.
山东半岛海岸带面临着各类复杂的环境问题,尤其是受到了多环芳烃(PAHs)等持久性有机物的污染,本文研究了整个山东半岛典型海岸带62个站点表层沉积物中PAHs的含量及其分布特征,并对其来源和潜在风险进行解析与评价。研究表明,该地区表层沉积物中16种PAHs总含量为0.06~3191.40 ng/g(平均值262.08 ng/g),与国内外海岸带相比,山东半岛海岸带表层沉积物中PAHs整体污染状况处于较低水平,但个别站点的PAHs含量偏高。运用特征比值法、相关性分析及主成分分析法解析研究区PAHs主要来源为木柴、煤炭、油类的燃烧以及油类泄露的联合作用。采用效应区间低值法(ERL)和中值法(ERM)对PAHs进行生态风险评价,结果表明莱州湾周边所有站点及威海、青岛周边个别站点苊、芴浓度位于ERL值与ERM值之间,但多数站点对生态环境潜在负面效应很小。山东半岛典型海岸带中PAHs对生物的毒副作用尚在安全可控范围内,极少对生态环境产生负面效应。  相似文献   
15.
ABSTRACT

The sinking of the MV Rena on Astrolabe Reef (Otaiti) in the Bay of Plenty, New Zealand, resulted in the release of oil and ship debris, including dangerous goods carried as cargo. Two key questions of concern to the public and environmental managers were posed immediately: what was the impact of the Rena oil spill and how long would it take for the marine environment to recover? The research that began immediately after the ship grounded provided answers, as documented in this special issue.  相似文献   
16.
ABSTRACT

To investigate the uptake and depuration of polycyclic aromatic hydrocarbons associated with the Rena oil spill we sampled the surf clam Paphies subtriangulata at two open coast locations (6?km apart) just prior to oil coming ashore (7 October 2011), then at 1–3 week intervals for the next 4 months. Total polycyclic aromatic hydrocarbons (tPAH) increased at both sites from 1 to 96–124?µg?kg?1 (wet weight) by 18 October before declining to low levels (<4?µg?kg?1) by February 2012. Ongoing sampling throughout 2012–2014 included three additional sites to the north east (up to 30?km away) and a site 5?km to the south east revealing tPAH levels generally <10?µg?kg?1 except in October 2013 where levels ranged between 39–45?µg?kg?1 at all sites. A comparison of PAH component profiles with oil-contaminated beach sediment indicated that the high levels observed in surf clams between October–December 2011 were clearly associated with the Rena spill. However, the October 2013 peak had a PAH profile inconsistent with weathered Rena oil, suggesting an alternative source of contamination. Our results highlight the potential for P. subtriangulata as a PAH monitoring tool but recognise more study is needed to better quantify baseline levels and uptake and depuration dynamics.  相似文献   
17.
以芘为唯一碳源,对采自于天津港石油污染区的海水和土壤样品进行富集培养,分离到1株芘降解菌,经显微形态观察、生理生化鉴定、16S rRNA基因序列的比对及系统发育进化的分析,确定该菌株为施氏假单孢菌Pseudomonas stutzeri,并采用室内培养方法,对其进行了芘降解性能的测定及降解途径的分析.结果表明,该菌株在...  相似文献   
18.
黄宏  董巧香  黄长江 《海洋学报》2006,28(6):164-168
近岸海域是绝大数污染物的最终归宿,其中多环芳烃(PAHs)的污染目前已成为国内外环境问题的焦点之一[1~3].20世纪80年代以来,国内外对河口湾、港湾、近岸海域等海洋环境中PAHs的含量、组成、分布、归趋及来源等做了大量的调查[4~15].比如,中国科学院广州地化所对珠三角水域和厦门大学对厦门港一带均做了大量的工作,结果发现表层沉积物中16种优控PAHs总量在珠江口达到156~9220 ng/g,闽江口为175~817ng/g,厦门西港则在196~675 ng/g之间,证明我国东南沿海主要河口及港湾沉积物中的PAHs污染已经达到中等水平[13~15].  相似文献   
19.
南岭山地湖泊多环芳烃的大气沉降历史记录   总被引:1,自引:0,他引:1  
高大山脉对大气环流具有阻挡或屏障作用.通过分析测定南岭山地湖泊沉积物中多环芳烃(PAHs)的垂直分布,结合210Pb定年,探讨了大气PAHs污染在南岭山地的沉积历史.结果显示,沉积物中的PAHs主要以低环数化合物为主,其中尤以菲的含量为最高.在剖面深度0~28 cm范围内,总多环芳烃的含量范围为86~778 ng/g.自1970年开始,PAHs含量持续增加,其中20世纪80、90年代中后期PAHs含量略有降低;在2000年后,沉积柱中的PAHs含量呈急剧增加之势态.多环芳烃在大气迁移过程中发生了组成分异,沉积物中相对富集轻组分(低环数)PAHs,与颗粒物结合的大气干湿沉降是PAHs向偏远山地积的主要途径.  相似文献   
20.
A suite of marl samples from the evaporitic series of the Mulhouse basin (France; Lower Oligocene) was studied for its biomarker content, in particular its polar constituents. Novel series of 3-carboxyalkyl steranes and 15-oxo triaromatic ketones were identified by synthesis. The 3-carboxyalkyl steranes probably originate from highly polar precursors yet unreported in living organisms. Our data suggest that micro-algae could be the major source of these compounds which seem to be indicators of high algal input rather than characteristic of evaporitic environments. The 15-oxo triaromatic ketones could be oxidation products of triaromatic steroid hydrocarbons formed during diagenesis, although their formation during work-up procedure could not be excluded.  相似文献   
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