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Eleftheria Katsivela Edward R. B. Moore Nicolas Kalogerakis 《Water, Air, & Soil Pollution: Focus》2003,3(3):103-115
Indigenous microorganisms, enriched and isolated from refinery waste sludge, were observed to possess a broad range of metabolic activities for mixtures of several classes of substrates of petroleum hydrocarbons, such as monoaromatic and polycyclic aromatic hydrocarbons (PAHs) and n- and branched alkanes. Three of the best-growing bacterial isolates selectively enriched with these compounds were identified by 16S rDNA sequencing as belonging to the genera Enterobacter and Ochrobactrum. Two of them, Enterobacter sp. strain EK3.1 and Ochrobactrum sp. strain EK6 utilise a hydrocarbon mixture of the branched alkane 2,6,10,14-tetramethylpentadecane and the PAHs acenaphthylene and acenaphthene. Enterobacter sp. strain EK4 can grow with a mixture of 2,6,10,14-tetramethylpentadecane, toluene, acenaphthylene and acenaphthene as carbon sources. Nucleic acid fingerprint analysis, by terminal restriction fragment length polymorphism (T-RFLP) of the PCR-amplified 16S rRNA genes, of the autochthonous bacterial community in contaminated soil samples showed complex and different community structures under different treatments of refinery waste sludge in landfarm areas. The characteristic peaks of the T-RFLP profiles of the individual, isolated degrading bacteria Enterobacter spp. and Ochrobactrum sp. were detected in the T-RFLP fingerprint of the bacterial community of the four months old treated landfarm soil, suggesting the enrichment of bacteria belonging to the same operational taxonomic units, as well as their importance in degrading activity. 相似文献
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YOU Ke-wei GE Yun-shan HU Bin NING Zhan-wu ZHAO Shou-tang ZHANG Yan-ni XIE Peng 《环境科学学报(英文版)》2007,19(10):1208-1213
The types and quantities of volatile organic compounds (VOCs) inside vehicles have been determined in one new vehicle and two old vehicles under static conditions using the Thermodesorber-Gas Chromatograph/Mass Spectrometer (TD-GC/MS).Air sampling and analysis was conducted under the requirement of USEPA Method TO-17.A room-size,environment test chamber was utilized to provide stable and accurate control of the required environmental conditions (temperature,humidity,horizontal and vertical airflow velocity,and background VOCs concentration).Static vehicle testing demonstrated that although the amount of total volatile organic compounds (TVOC) detected within each vehicle was relatively distinct (4940μg/m~3 in the new vehicle A,1240μg/m~3 in used vehicle B,and 132μg/m~3 in used vehicle C),toluene,xylene,some aromatic compounds,and various C_7-C_(12) alkanes were among the predominant VOC species in all three vehicles tested.In addition,tetramethyl succinonitrile,possibly derived from foam cushions was detected in vehicle B.The types and quantities of VOCs varied considerably according to various kinds of factors,such as,vehicle age, vehicle model,temperature,air exchange rate,and environment airflow velocity.For example,if the airflow velocity increases from 0.1 m/s to 0.7 m/s,the vehicle's air exchange rate increases from 0.15 h~(-1) to 0.67 h~(-1),and in-vehicle TVOC concentration decreases from 1780 to 1201μg/m~3. 相似文献
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本文采用聚氨基甲酸乙酯泡沫和玻璃纤维滤膜,同时采集大气中气态和颗粒物样,用高效液相色谱和气相色谱分别测定了蒽、、、芘、苯并(a)、二苯并(a、h)葱、苯并(ghi)与C_(16)~C_(33)正构烷烃等有机污染物的含量。并得到了冬夏两季颗粒物和气态中有机污染物的分布规律。 相似文献
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The 2,4,6-trinitrotoluene(TNT)is a potential carcinogens and TNT contaminated wastewater,which could not be effectively disposed with conventional treatments.The supercritical water oxidation(SCWO)to treat TNT contaminated wastewater was studied in this article.The TNT concentration in wastewater was measured by high-performance liquid chromatograph(HPLC)and the degraded intermediates were analyzed using GC-MS.The results showed that SCWO could degrade TNT efficiently in the presence of oxygen.The reaction temperature,pressure,residence time and oxygen excess were the main contributing factors in the process.The decomposition of TNT was accelerated as the temperature or residence time increased.At 550℃,24 MPa,120 s and oxygen excess 300%,TNT removal rate could exceed 99.9%.Partial oxidation occured in SCWO without oxygen.It was concluded that supercritical water was a good solvent and had excellent oxidation capability in the existence of oxygen.The main intermediates of TNT during SCWO included toluene,1,3,5-trinitrobenzene,nitrophenol,naphthalene,fluorenone,dibutyl phthalate,alkanes and several dimers based on the intermediate analysis.Some side reactions,such as coupled reaction,hydrolysis reaction and isomerization reaction may take place simultaneously when TNT was oxidized by SCWO. 相似文献
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As a representative species of intermediate volatile organic compounds (IVOCs), long-chain alkanes are considered to be important precursors of secondary organic aerosols (SOA) in the atmosphere. This work reviews the previous studies on long-chain alkanes in the atmosphere: (1) the detection methods and filed observations of long-chain alkanes in both gas and particle phases are summarized briefly; (2) the laboratory studies of long chain alkanes are reviewed, the kinetic data, reaction mechanism, SOA yields, and physicochemical properties of SOA are included in detail; (3) the research progress related to model simulations of long-chain alkanes are also discussed. In addition, based on available research results, several perspective contents are proposed that can be used as a guideline for future research plans. 相似文献
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大气细颗粒物(PM2.5)中的非极性化合物包括多环芳烃(PAHs)和正构烷烃(n-alkanes)等,通常用于识别污染来源,且对人体健康和环境有很重要的影响.为探究广西背景点PM2.5中非极性有机气溶胶的污染特征及来源,于2017年11月至2018年10月,对野外采集的PM2.5样品分析了其中17种多环芳烃和20种正构烷烃.结果表明,多环芳烃和正构烷烃全年的平均值分别为(4.28±4.25)ng·m-3和(13.7±14.72)ng·m-3;季节变化规律均是:冬季[(7.86±5.19)ng·m-3和(27.51±16.9)ng·m-3]>春季[(2.73±1.76)ng·m-3和(7.64±4.71)ng·m-3]>秋季[(2.34±1.45)ng·m-3和(7.01±4.55)ng·m-3]>夏季[(1.91±1.67)ng·... 相似文献
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Degradative solidification/stabilization (DS/S) is a novel remediation technology that combines chemical degradation with conventional solidification/stabilization. The applicability of the Fe(II)-based DS/S to treating chlorinated alkanes was tested by characterizing degradation reactions of carbon tetrachloride (CT) and its daughter products in cement slurries containing Fe(II). Degradation kinetics of CT and chloroform (CF) were generally very rapid with reaction rates comparable to rates that can be obtained with zero-valent iron. Dechlorination reactions of CT proceeded primarily via a hydrogenolysis pathway, which yielded CF and methylene chloride (MC) as major products and chloromethane and methane as minor products. However, reaction pathways other than hydrogenolysis also appeared to be important at very high pH conditions. MC apparently was resistant to dechlorination reactions over a period of about two months. Kinetics of CT and CF transformation were strongly dependent on pH with an optimal value around 13, which was higher than found previously for PCE. When the initial CF concentration varied between 0.01 and 1 mM, and the Fe(II) dose was 104 mM, pseudo-first-order kinetics generally described the degradation reactions of CF. However, there was also some indication of substrate saturation kinetics in these experiments. This suggests that a saturation model would better describe the kinetics in systems with higher concentration of substrates or lower concentration of the reactive surfaces. 相似文献
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Base on the previous work in laboratory, a novel polyaniline doped with polydimethylsiloxane coating was developed on a stainless steel wire for solid phase microextraction(SPME) by electroplating method. This electroplating method not only has advantages of ease preparation and simple equipments required, but also increases the lifetime of the SPME fiber. The composite fiber(polyaniline/ polydimethylsiloxane(PANI/PDMS)) was evaluated by analyzing n-tridecane, n-tetradecane and n-pentadecane in aqueous sample. The new fiber coating showed comprehensive abilities to extract alkanes compounds. The relative standard deviations were found to be 6.8%-10.33%. 相似文献