微生物对芳香烃的降解作用

综述了微生物对芳香烃的降解作用，重点论述了在有氧和厌氧条件下，微生物对芳香烃的降解途径、作用机理及降解动力学；分析了微生物技术在环境治理中的应用前景。     

饮用水中微量有毒有机物活性炭处理技术初步研究

本初步研究了粒状活性炭和活性炭纤维对饮用水中多环芳香烃类(PAHs)、邻苯二甲酸酯类(pTEs)两大类微量有毒有机化台物的击除效率。结果表明，粒状活性炭对多环芳烃和邻苯二甲酸酯类的击除效果均很理想，活性擞纤维对多环芳烃的击除效果十分明显．但是，对邻苯二甲酸酯类的击除作用尚待进一步研究。     

Soil pollution by polycyclic aromatic hydrocarbons: A comparison of two Chinese cities

Soil samples from Huizhou and Zhanjiang, China were analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) with harmonized sampling, sample extraction and analysis quantification methods. The concentrations and sources of PAHs in soil samples of the two cities were compared. Almost all of the PAH components were detectable in 103 soil samples. The concentrations of ΣPAHs ranged from 35.40 to 534.5 g/kg in soil samples from Huizhou, and ranged from 9.50 to 6618.00 g/kg in samples from Zhanjiang. Evident differences of concentrations, compositions and sources of PAHs in soils were observed between the two cities. The average concentrations of individual component and the sum of a group of PAHs in soil samples from Zhanjiang were significantly higher than those in Huizhou (P < 0.05). Phe, Flu, Pyr, Bbf and Baa were the dominant PAH components both in soil samples from Huizhou and Zhanjiang. Except for these five components, Bap, I1p, Daa and Bgp were also the dominant PAH components in soil samples from Zhanjiang. Coal combustion and liquid fossil fuel combustion were the same sources of PAHs in the two cities with different contributions, and petroleum played a key role in PAHs release in Zhanjiang.     

全二维气相色谱法测定北京交通干道大气中芳香烃

为了更全面地获得城市大气中芳香烃的基础数据,借助具有强大分离、检测复杂样品能力的全二维气相色谱法(GC×GC),于2007年国庆期间对北京交通干道大气中芳香烃进行了采样分析和初步研究.结果表明,该方法对大气中芳香烃检测范围较一维气相色谱法宽,可同时测定单环芳烃和部分多环芳烃,并能将目标芳香烃更好地分离和定量.观测期间,在北京交通干道大气中检测出30多种芳香烃,其中,单环芳烃平均浓度为0.75×10-9~24.64×10-9C(碳单位体积比),甲苯浓度最高,间、对二甲苯与乙苯浓度次之;多环芳烃平均浓度为0.03×10-9~2.28×10-9C,萘浓度最高,2-甲基萘、4-甲基联苯浓度次之;四环以上的稠环芳烃则没有检出.芳香烃浓度变化明显受天气因素影响.高碳数芳香烃之间相关性很高,而苯、甲苯与高碳数的芳香烃相关性较差,表明两者可能受汽车尾气和汽油挥发之外的其它源的显著影响.     

深圳大气中VOCs的二次有机气溶胶生成潜势

使用气溶胶生成系数法和产率法,对深圳四季5种芳香烃和异戊二烯所生成的二次有机气溶胶(SOA)量分季节计算并比较得出:四季中除春季外,其余三季产率法计算得到的SOA量均高于生成系数法计算的结果,四季所生成SOA的平均值分别为(2.48±2.02)μg/m3和(2.10±1.21)μg/m3. 2种方法计算结果均为夏季SOA的生成量最大,秋季和冬季次之,春季最小.生成系数法计算得出人为源和天然源的贡献分别为96%和4%,而产率法得到两种源的贡献分别为86%和14%.将生成系数法和产率法计算得到的夏季SOA值与实测值进行比较,发现计算值均低于实测值,分别占实测值的21%和31%.最后计算芳香烃和异戊二烯的自由基反应速率得出,与OH自由基反应是其生成SOA最主要的途径,比例为75%,与NO3自由基和O3的反应比例分别为22%和3%.在生成SOA速度上,苯乙烯的速度最快,苯的速度最慢.     

室内空气中芳香烃的测定与污染源模拟

采用Ｔｅｎａｘ树脂吸附－热解吸／氢火焰气相色谱法定量测定室内空气中芳香烃类有机的。现场采样测定了某办公楼装修前后室内空气环境中芳香烃浓度。     

TCDD对胶质母细胞瘤中环氧合酶2基因表达的影响和生物学作用

胶质母细胞瘤(glioblastoma, GBM)是最常见的恶性脑肿瘤,其复发率和死亡率居高不下。环氧合酶2(cyclooxygenase 2, COX2)在正常生理条件下几乎不表达,但持续高表达的COX2常见于各种恶性肿瘤和癌前状态,并参与诸多肿瘤发生发展过程,如血管生成、免疫抑制、迁移侵袭以及化疗抵抗等。二噁英类污染物作为一级致癌物,但目前有关二噁英对GBM发展的研究十分有限。本研究旨在探究二噁英暴露影响GBM发展的分子机制。以COX2为标志物,明确二噁英类污染物中毒性最强的2,3,7,8-二苯并-p-二噁英(2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD)对胶质母细胞瘤U87细胞中COX2基因表达的影响以及芳香烃受体(aryl hydrocarbon receptor, AhR)在之中的作用,并借助转录组测序进一步探究TCDD暴露后U87细胞中COX2参与的生物过程。实验结果显示,TCDD以AhR依赖的方式上调U87细胞中COX2基因表达并具有时间-剂量依赖效应。转录组分析结果表明,TCDD暴露显著改变了U87细胞中细胞黏附、胞外刺激检测以及膜...     

Polycyclic aromatic hydrocarbon in rain and street runoff in Amman, Jordan

Concentrations of polycyclic aromatic hydrocarbons(PAHs) were determined in the rain and street runoff samples from two sites in the vicinity of Amman City during the pluvial period 1999--2000. The results showed that elevated levels of PAHs were detected in the city center(site 1 ) than the residential area( site 2) and that the levels were higher in street runoff than rain samples of the same sites. The highest concentration of PAHs in both street runoff and rain samples were observed in the first rainy month( November 1999) which indicated a wash out effect of PAHs originating from vehicular emission accumulated during the long dry summer season before sampling. Within the investigated cold winter seasons, fluctuations in PAHs concentration were observed. The variation was attributed to the fossil combustion for heating purposes and to intervals between rainfalls: as the longer the intervals between rains were, the higher the PAH concentration were. Removal of PAHs from the atmosphere through precipitation over the investigated period varied with time and places depending on the amount of rainfall where higher rainfall removed higher amount of PAHs from the almosphere. The amount of PAHs washed out through precipitation was estimated to be around 14.8 mg/m^2 and 21.1 mg/m^2 for sites 1 and 2 respectively.     

卷烟烟气对机体的氧化损伤

吸烟是目前世界上影响最广泛的公害之一，可导致多种肺部疾病。现有研究表明，氧化损伤是吸烟引发健康问题的重要原因之一。卷烟烟气本身含有大量自由基，测定表明，一支烟所产生的烟雾约含有10^15个自由基，其中气相中有烷氧基（RO·）、烷过氧基（ROO·）及烷基（R·）等，焦油相中有半醌自由基和芳香烃自由基等，     

反向PCR法克隆芳香烃龙胆酸降解途径中诱导型龙胆酸1,2-加双氧酶基因

龙胆酸1,2-加双氧酶(GDO)是芳香烃龙胆酸途径的一个关键酶.产碱假单胞菌P25X具有保守性与诱导性各一组GDO同工酶,突变株SNZ28的保守型龙胆酸1,2加双氧酶基因(GDOⅠ)被链霉素/奇霉素抗性基因打断,但在含有龙胆酸盐的基本培养基上,仍能明显观察到GDO的活性.由龙胆酸诱导生长的SNZ28全蛋白二维电泳结果分析,获得了一个与Ralstoniasp.U2的GDO酶有极高同源性的蛋白点.根据对该蛋白点的N端和Q-Tof测序的结果,设计了一对简并引物,克隆了诱导型GDO酶的片段,通过对此片段的分析,设计了逆向PCR引物,利用Southern blot杂交,确定了合适的限制性内切酶(SalⅠ和SphⅠ),以单一酶切的P25X基因组DNA自联后的产物为模板,进行反向PCR.测序表明,获得了一段1047bp与Ralstoniasp.U2.的龙胆酸1,2-加双氧酶具有极高同源性的序列.研究结果揭示了SNZ28中存在诱导型GDO酶.本文中也对不同来源的GDO酶进行了比较研究,其结果为进一步对生物降解基因的进化研究打下了基础.图4表2参16