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1.
Benzo(a)pyrene (BaP) and pyrene (Pyr) are two polycyclic aromatic hydrocarbons (PAHs) showing native fluorescence in solution. Both compounds have been determined in water at trace levels by solid-phase spectrofluorimetry, in which BaP and Pyr are fixed on Sephadex G-25 gel and the relative fluorescence intensity is measured after the system is packed in a 1-mm silica cell. First-derivative synchronous spectra obtained at =38 nm were used to determine BaP and Pyr in the presence of other potentially interferent PAHs. The spectral characteristics of the PAHs-gel system are described, the applicable concentration ranges being 0.4–2.5 ng/ml for BaP and 0.7–4.5 ng/ml for Pyr. The relative standard deviations were 1.1% and 1.4% for BaP and Pyr respectively. The detection limits were 0.04 ng/ml for BaP and 0.1 ng/ml for Pyr. The method was applied to the analysis of both compounds in water at trace levels and a recovery study on tap, natural and sea waters was carried out.  相似文献   

2.
The synchronous fluorescence (SF) technique has been used in the identification of polycyclic aromatic hydrocarbons (PAHs) from air particulate sample in an urban environment of Delhi, Jawaharlal Nehru University. Suspended particulate matter samples of 24h duration were collected on glass fiber filter papers. PAHs were extracted from the filter papers using dichloromethane (DCM)+hexane with ultrasonication method. Qualitative measurements of the polycyclic aromatic hydrocarbons (PAHs) were carried out using the SF technique at various wavelength intervals (Deltalambda). Due to the difference in chemical structure, each PAH gives specific characteristic spectrum for each Deltalambda. Following PAHs were detected in our measurement: benz(a)anthracene (BaA), pyrene (Pyr), chrysene (Chry), fluoranthene (Flan), phenanthrene (Phen), and benz(ghi)perylene (BghiP). This is in agreement with our earlier work for determination of these PAHs using gas chromatography (GC). The seasonal variation of the PAHs was found to be maximum in winter and minimum during the monsoon.  相似文献   

3.
该文以渤海原油SZ36-1为研究对象进行综合模拟风化实验,探讨了原油中生物标志物及5类多环芳烃(PAHs)组分的分布情况及风化规律。结果表明:经过30 d风化,渤海原油SZ36-1中大部分生物标志物表现出强的稳定性,部分PAHs的分布发生较大改变,其中萘系列化合物损失最严重,相对浓度的损失达80.34%;菲、二苯并噻吩、、芴系列则相对稳定;经t检验分析风化样品测试数据,生物标志物诊断比值表现出良好的稳定性,所选取多环芳烃新诊断比值中,菲和系列、烷基取代二苯并噻吩类、烷基取代芴类的抗风化能力较强,可用于油源鉴别。  相似文献   

4.
Particle-associated polycyclic aromatic hydrocarbons (PAHs) collected in urban air of Beijing were studied using a gas chromatograph mass spectrometer (GC/MS). The average concentration of particle-associated PAHs measured in this work was in the range from 28.53 to 362.15 ng/m3, which suggested a serious pollution level of PAHs in Beijing. The results also showed that the concentration of PAHs in the winter was distinctly higher than that in summer and spring. Benzo(a)pyrene (BaP) and benzo(a)pyrene-equivalent carcinogenic power (BaPE) were adopted to evaluate the PAHs pollution state at the sampling site. Through some diagnostic ratios, it can be concluded that traffic exhaust, especially vehicles with diesel engines, and domestic coal-burning heaters might have a prominent contribution to the PAHs concentration.  相似文献   

5.
Paolo Bruno  Maria Tutino 《Talanta》2007,72(4):1357-1361
The determination of polycyclic aromatic hydrocarbons (PAHs) contained in samples of particulate matter (PM), collected with low volume pumps, were carried out with an high sensitivity method that comes from several revisions of a previous method. The present work describes how, by using programmable temperature vaporization (PTV) and a mass selective detector with inert ionic source for the GC-MS analysis and the modifications of microwave-assisted extraction (MAE), the sensitivity of the method can be increased.The PAHs chosen for testing the method are: benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (Ip) and dibenzo[a,h]anthracene (DbA). They, in fact, belong to that group of substances that are the most harmful for human health for their carcinogenicity.PAHs recoveries for spiked standard solutions at different concentrations were between 95 and 100% with relative standard deviation ranging from 1 to 3%. The revised method was validated using a 1649a urban dust standard reference material (SRM). The results obtained were in good agreement with certified values. The high sensitivity of the method allows to carry out analyses using only a half of the sampled filter (usually 47 mm diameter membranes). In this way, the other half can be used for the characterization of the other components of PM (heavy metals, organic carbon, ions, etc). The last step has been constituted by application of the optimized method on real samples collected in two cities located in Southern Italy (Bari and Taranto).  相似文献   

6.
Every petroleum-processing plant produces sewage sludge containing several types of polycyclic aromatic hydrocarbons (PAHs). The degradation of PAHs via physical, biological, and chemical methods is not yet efficient. Among biological methods, the use of marine sponge symbiont bacteria is considered an alternative and promising approach in the degradation of and reduction in PAHs. This study aimed to explore the potential performance of a consortium of sponge symbiont bacteria in degrading anthracene and pyrene. Three bacterial species (Bacillus pumilus strain GLB197, Pseudomonas stutzeri strain SLG510A3-8, and Acinetobacter calcoaceticus strain SLCDA 976) were mixed to form the consortium. The interaction between the bacterial consortium suspension and PAH components was measured at 5 day intervals for 25 days. The biodegradation performance of bacteria on PAH samples was determined on the basis of five biodegradation parameters. The analysis results showed a decrease in the concentration of anthracene (21.89%) and pyrene (7.71%), equivalent to a ratio of 3:1, followed by a decrease in the abundance of anthracene (60.30%) and pyrene (27.52%), equivalent to a ratio of 2:1. The level of pyrene degradation was lower than that of the anthracene due to fact that pyrene is more toxic and has a more stable molecular structure, which hinders its metabolism by bacterial cells. The products from the biodegradation of the two PAHs are alcohols, aldehydes, carboxylic acids, and a small proportion of aromatic hydrocarbon components.  相似文献   

7.
This paper presents an optosensor for screening of four polycyclic aromatic hydrocarbons: anthracene (ANT), benzo[a]pyrene (BaP), fluoranthene (FLT), and benzo[b]fluoranthene (Bbf) using a photomultiplier device with an artificial neural network as transducer. The optosensor is based on the on-line immobilization on a non-ionic resin (Amberlite XAD-4) solid support in a continuous flow. The determination was performed in 15 mM H2PO4/HPO42− buffer solution at pH 7 and 25% of 1,4-dioxane. Feed forward neural networks (multiplayer perceptron) have been trained to quantify the considered Polycyclic aromatic hydrocarbons (PAHs) in mixtures under optimal conditions. The optosensor proposed was also applied satisfactorily to the determination of the considered PAHs in water samples in presence of the other 12 EPA–PAHs.  相似文献   

8.
Polycyclic aromatic hydrocarbons (PAHs) constitute an important group of micropollutants, which are known to be mutagenic, carcinogenic and/or co-carcinogenic and relatively persistent in the environment. The effects of chlorine dioxide (ClO2) on the degradation of anthracene (ANTH), pyrene (PYR) and benzo[a]anthracene (BaA) in aqueous solution were investigated using high performance liquid chromatography (HPLC). In preliminary experiments, it was observed that ClO2 could remove these three PAHs effectively within a short time. Several factors including reaction time, the concentration of ClO2 and pH of the reaction mixture influencing the degradation ratio of PAHs have been studied by batch experiments. The results showed that the degradation ratio of PAHs was affected by reaction time and the concentration of ClO2 instead of pH. The degradation ratio of ANTH, PYR and BaA could reach their maximum as approximately 99.0%, 67.5% and 89.5%, respectively, under the condition as follows: reaction time 30, 60 and 120 min, the concentration of ClO2 0.1, 0.4 and 0.5 mmol·L-1, and pH 7.2. ANTH was selected as the representative to study the reaction mechanism with ClO2. The oxidation products formed in the reaction of ANTH with ClO2 were tentatively identified by gas chromatography-mass spectrometry (GC-MS), and the results showed that the main product was 9, 10-anthraquinone, which could be biodegraded more easily and quickly than ANTH. Through analyzing the reaction properties of ANTH and ClO2, the possible pathway for the ANTH-ClO2 reaction was proposed based on the theory of single electron transfer (SET).  相似文献   

9.
A collaborative study was conducted to validate an analytical method for quantification of the 15 polycyclic aromatic hydrocarbons (PAHs) regarded in 2002 as a health concern by the former Scientific Committee on Food of the European Commission (SCF) in primary smoke condensates. The method is based on gas chromatography/mass spectrometry of a cyclohexane extract with solid-phase cleanup through silica gel. The analytes were detected in the selected-ion monitoring mode and quantified by using 3 isotopically labeled internal standard compounds. Seventeen laboratories participated in the collaborative validation study, of which 12 reported valid results. The data were subjected to Cochran, single Grubbs, and double Grubbs tests for statistical outliers. A maximum of 2 outliers was eliminated before further statistical evaluation of the method performance characteristics. Depending on the analyte, the results showed relative standard deviations for repeatability between 4.2 and 30% and for reproducibility from 9.9 to 60%. The recoveries varied between about 50 and 85%, except those for cyclopenta[cd]pyrene, dibenzo[a,l]pyrene, and dibenzo[a,h]pyrene. Nevertheless, because Commission Directive 2005/10/EC allows for a recovery range of 50-120% for (BaP) benzo[a]pyrene in various foods, it can be concluded that the method performs appropriately within the analytical range between 5 and 25 microg/kg of primary smoke condensate. For BaP the validated analytical range covered 5-20 microg/kg, and for benzo[a]anthracene (BaA) 10-25 microg/kg. The method is suitable for monitoring BaP and BaA at their respective maximum permitted levels of 10 and 20 microg/kg. Three analytes, benzo[b]-, benzo[j]-, and benzo[k]-fluoranthene could not be separated by all of the participants and were therefore treated as the sum. Nevertheless, with this method the pattern of the respective concentrations of these 15 PAHs can be monitored in primary smoke condensate as suggested by the SCF.  相似文献   

10.
以多环芳烃作为变量,建立了原油、燃料油属性鉴别的费谢尔判别法。分别测定了来自不同国家和地区的26个原油样品和25个燃料油样品中8种多环芳烃的含量,并将它们作为判别变量。借助SPSS 16.0进行费谢尔判别分析,建立费谢尔判别函数。将未知样品的判别变量值代入后,可以快速地得知样品的类别。结果表明,以多环芳烃作为判别变量进行原油、燃料油费谢尔判别快速而准确。  相似文献   

11.
Benzo[a]pyrene (BaP) is ubiquitously distributed in the environment, being considered the most phototoxic element among polycyclic aromatic hydrocarbon (PAHs). In presence of oxygen, PAHs can act as a photosensitizer by means of promoting photo-oxidation of biological molecules (photodynamic action, PDA). Thus, the present study analyzed the photodynamic action of BaP under UVA irradiation (BaP + UVA) and its oxidative effects on K562 cells. The evaluation of BaP kinetics showed that the highest intracellular concentration occurred after 18 h of incubation. Cell viability, reactive oxygen species (ROS) generation, lipid peroxidation, DNA damage (breaks and DNA-protein cross-link [DNAPC]) were assessed after exposure to BaP, UVA and BaP plus UVA irradiation (BaP + UVA). Cell viability was decreased just after exposure to BaP + UVA. Lipid peroxidation and DNA breaks increased after BaP + UVA exposure, while the DNAPC increased after BaP, UVA and BaP + UVA exposure, suggesting that BaP + UVA effects were a consequence of both type II (producing mainly singlet oxygen) and type I (producing others ROS) mechanisms of PDA.  相似文献   

12.
多环芳烃指纹用于渤海采油平台原油的鉴别   总被引:5,自引:0,他引:5  
采用气相色谱/质谱方法,对渤海海上4个不同区块、5个平台的6口油井原油进行了烷基化多环芳烃系列化合物和美国环保署(EPA)优先控制多环芳烃系列化合物的准确定性定量分析。通过多环芳烃原始指纹谱图、多环芳烃组分分布模式和特征比值的比较对上述原油进行鉴别。结果证明不同区块的原油中多环芳烃指纹信息不尽相同,即使在同一平台不同油井中所产的原油其指纹也存在一定差异。为确保原油鉴别的准确性,分析过程中必须在仪器的稳定性和样品前处理方面实施严格的质量控制措施。  相似文献   

13.
The polycyclic aromatic hydrocarbons (PAHs) biodegradation potential of the five basidiomycetes' fungal monocultures and their cocultures was compared with that of a Pseudomonas isolate recovered from oil-spilled soil. As utilization of hydrocarbons by the microorganisms is associated with biosurfactant production, the level of biosurfactant production and its composition by the selected microorganisms was also investigated. The Pseudomonas isolate showed higher ability to degrade three of the five PAHs but the isolate did not produce biosurfactant higher than C. versicolor and P. ostreatus. Among the PAHs, the most effective biodegradation of PAH--pyrene (42%)--was obtained with the fungus C. versicolor. Cocultures involving the fungi and Pseudomonas could not significantly degrade the selected PAHs compounds above that degraded by the most efficient monoculture. A slight increase in pyrene degradation was observed in cocultures of C. versicolor and F. palustris (93.7% pyrene). The crude biosurfactant was biochemically characterized as a multicomponent surfactant consisting of protein and polysaccharides. The PAH biodegradation potential of the basidiomycetes fungi positively correlated with their potential to express ligninolytic enzymes such as lignin peroxidase (Lip), manganese peroxidase (Mnp), and laccase. The present study utilized in silico method such as protein-ligand docking using the FRED in Open Eye software as a tool to assess the level of ligninolytic enzymes and PAHs interactions. The in silico analysis using FRED revealed that of the five PAHs, maximum interaction occurred between pyrene and all the three ligninolytic enzymes. The results of the in silico analysis corroborated with our experimental results showing that pyrene was degraded to the maximum extent by species such as C. versicolor and P. ostreatus.  相似文献   

14.
童婷  张万峰  李东浩  赵锦花  常振阳  高儇博  代威  何生  朱书奎 《色谱》2014,32(10):1144-1151
建立了气流吹扫-注射器微萃取(GP-MSE)与全二维气相色谱/飞行时间质谱(GC×GC/TOFMS)联用分析原油成分的方法。为了找到适用于原油样品分析的GP-MSE条件,用饱和烃混合标准溶液和15种芳烃的混合标准溶液进行了条件优化,得到的最佳条件如下:取样量5 mg、萃取溶剂正己烷20 μ L、载气流速2 mL/min、加热时间3 min、加热温度300 ℃、冷凝温度-2 ℃。处理后的样品在全二维色谱/飞行时间质谱上进样分析,得到了满意结果。方法的检出限为34~93 μg/L,线性相关系数(R2)>0.99,对50种烃类化合物的回收率在82.0%~107.3%之间,相对标准偏差<10%(n=5)。结果表明GP-MSE-GC×GC/TOFMS法是一种新型绿色、高效、灵敏的分析方法,非常适合原油中挥发性与半挥发性组分的分析。  相似文献   

15.
原油空气氧化前后多环芳烃组分的气相色谱-质谱分析   总被引:2,自引:0,他引:2  
采用柱层析法对空气氧化前后的原油进行族组分分离,利用气相色谱-质谱(GC-MS)分离测定其芳香烃组分,分析多环芳烃组分的变化.结果表明,随着氧化过程的进行,烷基化多环芳烃占多环芳烃的含量从氧化前的71.5%增加到92.0%(175℃)和90.2%(225℃).轻质组分萘和菲的优势逐渐被重质组分艹屈取代.侧链少的多环芳烃比侧链多的更易氧化.氧化后,其他稠环化合物蒽、萤蒽、芘、苯并蒽含量降低,苯并萤蒽含量增加;苯并芘在175℃氧化后含量降低,而在225℃氧化后含量增加.与此同时,175℃氧化后生成了原油所不含有的三芳甾烃、联苯和苯并呋喃.  相似文献   

16.
应用紫外分光光谱技术建立了快速测定原料油中芳香烃含量的方法。分别以色谱分离法提纯的蜡油、柴油芳香烃组分为标准物,绘制标准曲线。实验表明蜡油和柴油中芳香烃的含量与吸光度具有良好的线性关系(相关系数r2分别为0.999 73,0.999 44),蜡油和柴油中芳烃的加标回收率分别为96.83%,98.97%。蜡油和柴油中芳烃测定结果的相对标准偏差分别为0.32%~0.98%,0.89%~1.52%(n=6)。该方法进行原料油可磺化有效组分的检测快速可靠,能更好地应用于实际生产。  相似文献   

17.
This paper describes a case study in which advanced chemical fingerprinting and data interpretation techniques were used to characterize the chemical compositions and determine the source of an unknown spilled oil from Quebec. On 28 February 1999, significant amounts of oil was reported on the river banks of St. Laurence River in front of a company named "Thermex" (in a town - Beauharnois, Quebec, about 50 km northwest of Montreal). The spilled oil was suspected to be released from a nearby factory. In response to this specific site investigation needs, a tiered analytical approach using GC-MS and GC-flame ionization detection was applied. A variety of diagnostic ratios of "source-specific marker" compounds, in particular isomers of biomarkers and alkylated series of polycyclic aromatic hydrocarbons within the same alkylation groups, were determined and analyzed. The hydrocarbon analysis results reveal the following: (1) the spilled oil is very "specific", and is significantly different from most crude oils in chemical composition; (2) the oil in samples come from the same source, however, the spill sample 2569 was identified to contain a small amount (approximately 10%) of diesel; (3) the spilled oil was relatively "fresh", its chemical composition has not undergone significant alteration yet; (4) the spilled oil showed unusually high concentration of the US Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs). The "Pyrogenic Index" values were determined to be as high as 0.11-0.13, significantly higher than crude oils (<0.010) and heavy Bunker type fuels (0.015-0.060). This indicates significant contribution of PAH composition from pyrogenic components; (5) biomarkers were also detected, but their concentrations were unusually low in comparison to most crude oils.  相似文献   

18.
Abstract

We report the direct determination of two polycyclic aromatic hydrocarbons (PAH), Benzo(a)Pyrene [B(a)P] and Pyrene (Pyr), in solid environmental samples, i.e. a marine sediment and scrapings from the interior walls of a steel foundry, by the supersonic jet/laser induced fluorescence technique. We have found limits of detection (LOD) for these samples of 900ng (1.8ppm) for B(a)P and 200ng (0.4ppm) for Pyr. The LOD's for prepared solutions were 100 ng for B(a)P and 40 ng for Pyr. In validating the procedure we have also analyzed a standard mixture of PAH. The results of our analyses of the solid environmental samples agree well with those obtained by chromatography in other laboratories. We have found evidence of incomplete recovery of PAH from soil sediments by a prolonged low temperature Soxhlet extraction using methylene chloride.  相似文献   

19.
Polycyclic aromatic hydrocarbons (PAHs) and geochemical biomarkers are good environmental markers to study the origin and evolution of an oil spill. To have access to the greatest number of molecular ratios, no fractionation of oil into aliphatic and aromatic compounds is made. Three analytical MS approaches are tested to analyze markers in this total hydrocarbon fraction: classical quadrupole GC-MS, high resolution GC-MS (HR GC-MS) and metastable reaction monitoring GC-MS-MS (MRM GC-MS-MS). This analytical approach is used to follow the evolution of PAHs in petroleum polluted mangrove soils over 8 years by using molecular ratios between polycyclic aromatic hydrocarbons and tri- and tetracyclic terpanes.  相似文献   

20.
优化了土壤中16种优控多环芳烃( PAHs)的分析方法,建立了一套完备的质量控制体系,解决了PAHs分析中常见的技术难点,如苯并(a)芘(BaP)回收率低,基质复杂的样品净化效果不理想,萘(Nap)和菲(Phe)挥发损失和环境本底影响等.样品经加速溶剂提取(ASE),固相萃取(SPE)净化,逐级减压浓缩,气相色谱质谱( GC - MS)测定,并以氘代苯并a芘(BaP - d12)作回收率指示物.实验比较了3种正相SPE吸附剂的效果,发现弗罗里硅土对BaP存在明显的降解现象,BaP的定量应使用同位素稀释法,以降低其分析不确定度;氧化铝对PAHs的吸附性过强,不利于样品净化;硅胶最为理想.PAHs的仪器检出限为0.26~5.7 pg,方法检出限为0.067 ~0.97 ng/g(干重),土壤基质加标回收率为71%~ 122%,相对标准偏差为1.6%~8.3%.将该法用于7个电子废物焚烧区域农田土壤样品的测定,PAHs含量在28~ 283 ng/g(干重)之间,样品中BaP-d12的回收率为90%~124%,各项质控指标符合检测要求.  相似文献   

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