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21.
Characterization of Volatile Organic Compounds (VOCs) and Their Sources in the Air of Izmir, Turkey 总被引:1,自引:0,他引:1
Elbir T Cetin B Cetin E Bayram A Odabasi M 《Environmental monitoring and assessment》2007,133(1-3):149-160
Air samples were collected in Izmir, Turkey at two (suburban and urban) sites during three sampling programs in 2002 and 2004
to determine the ambient concentrations of several monoaromatic, chlorinated and oxygenated volatile organic compounds (VOCs).
Samples were analyzed for 60 VOCs using gas chromatography/mass spectrometry and 28 compounds were detected in most samples.
On the average, urban air VOC concentrations were about four times higher than those measured at the suburban site. Toluene
(40.6%) was the most abundant compound in suburban site and was followed by benzene (7.4%), o,m-xylene (6.5%), and 1,2-dichloroethane
(5.1%). In urban site, toluene (30.5%), p-xylene (14.9%), o,m-xylene (11.4%), and ethyl benzene (7.2%) were the dominating
compounds in summer. In winter, toluene (31.1%), benzene (23.9%), 1,2-dichloroethane (9.5%), and o,m-xylene (8.2%) were the
most abundant compounds. Receptor modeling (positive matrix factorization) has been performed to estimate the contribution
of specific source types to ambient concentrations. Six source factors (gasoline vehicle exhaust, diesel vehicle exhaust+residential
heating, paint production/application, degreasing, dry cleaning, and an undefined source) were extracted from the samples
collected in the urban site. Three source factors (gasoline vehicle exhaust, diesel vehicle exhaust, and paint production/application)
were identified for the suburban site. 相似文献
22.
Mehmet Ekmekçioğlu Tolga Kaya Cengiz Kahraman 《Waste management (New York, N.Y.)》2010,30(8-9):1729-1736
The use of fuzzy multiple criteria analysis (MCA) in solid waste management has the advantage of rendering subjective and implicit decision making more objective and analytical, with its ability to accommodate both quantitative and qualitative data. In this paper a modified fuzzy TOPSIS methodology is proposed for the selection of appropriate disposal method and site for municipal solid waste (MSW). Our method is superior to existing methods since it has capability of representing vague qualitative data and presenting all possible results with different degrees of membership. In the first stage of the proposed methodology, a set of criteria of cost, reliability, feasibility, pollution and emission levels, waste and energy recovery is optimized to determine the best MSW disposal method. Landfilling, composting, conventional incineration, and refuse-derived fuel (RDF) combustion are the alternatives considered. The weights of the selection criteria are determined by fuzzy pairwise comparison matrices of Analytic Hierarchy Process (AHP). It is found that RDF combustion is the best disposal method alternative for Istanbul. In the second stage, the same methodology is used to determine the optimum RDF combustion plant location using adjacent land use, climate, road access and cost as the criteria. The results of this study illustrate the importance of the weights on the various factors in deciding the optimized location, with the best site located in Çatalca. A sensitivity analysis is also conducted to monitor how sensitive our model is to changes in the various criteria weights. 相似文献
23.
An integrated approach using the contamination levels and DNA damage in mussels (Mytilus galloprovincialis) was applied in order to assess the chemical contamination in a marina (Eastern coastline of Aegean Sea). Mussels, which were harvested from a reference site (Foca), were transplanted into a marina situated along the coast of Izmir Bay. The transplanted mussels were collected at the 14th, 30th and 60th day of the experimental period. Polycyclic aromatic hydrocarbon (PAH) levels (27–51?ng?g?1?wet?weight) detected in the mussels were similar to the levels detected in other coastal areas of the Mediterranean Sea. The marina’s sediment was found to be contaminated with PAHs (∑PAH?=?25?µg?g?1) of pyrolytic origin and may become a source of pollution and a threat to the marine environment. In order to assess the DNA damage, the haemolymph and gill cells of the mussels were used for the comet analysis and considered as an indicator of exposure to genotoxic chemicals including 16 PAH compounds and metals. The highest levels of DNA damage expressed as %Tail-DNA (%T-DNA) were observed at the end of the experiment (21.5% T-DNA). The correlation analyses conducted between 2-, 3-, 4-ring PAHs in mussels and %T-DNA in haemolymph and gill cells showed a significant positive correlation. This investigation confirmed that transplanted mussel can be a useful tool to determine PAH contamination in marinas. 相似文献
24.
Environmental Modeling & Assessment - This study applies a large battery of state-of-the-art nonlinear unit root tests to examine the stationarity properties of carbon dioxide emission series... 相似文献