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961.
Atmospheric emissions and attenuation of non-methane organic compounds in cover soils at a French landfill 总被引:1,自引:0,他引:1
Scheutz C Bogner J Chanton JP Blake D Morcet M Aran C Kjeldsen P 《Waste management (New York, N.Y.)》2008,28(10):1892-1908
In addition to methane (CH(4)) and carbon dioxide (CO(2)), landfill gas may contain more than 200 non-methane organic compounds (NMOCs) including C(2+)-alkanes, aromatics, and halogenated hydrocarbons. Although the trace components make up less than 1% v/v of typical landfill gas, they may exert a disproportionate environmental burden. The objective of this work was to study the dynamics of CH(4) and NMOCs in the landfill cover soils overlying two types of gas collection systems: a conventional gas collection system with vertical wells and an innovative horizontal gas collection layer consisting of permeable gravel with a geomembrane above it. The 47 NMOCs quantified in the landfill gas samples included primarily alkanes (C(2)-C(10)), alkenes (C(2)-C(4)), halogenated hydrocarbons (including (hydro)chlorofluorocarbons ((H)CFCs)), and aromatic hydrocarbons (BTEXs). In general, both CH(4) and NMOC fluxes were all very small with positive and negative fluxes. The highest percentages of positive fluxes in this study (considering all quantified species) were observed at the hotspots, located mainly along cell perimeters of the conventional cell. The capacity of the cover soil for NMOC oxidation was investigated in microcosms incubated with CH(4) and oxygen (O(2)). The cover soil showed a relatively high capacity for CH(4) oxidation and simultaneous co-oxidation of the halogenated aliphatic compounds, especially at the conventional cell. Fully substituted carbons (TeCM, PCE, CFC-11, CFC-12, CFC-113, HFC-134a, and HCFC-141b) were not degraded in the presence of CH(4) and O(2). Benzene and toluene were also degraded with relative high rates. This study demonstrates that landfill soil covers show a significant potential for CH(4) oxidation and co-oxidation of NMOCs. 相似文献
962.
Armijo de Vega C Ojeda Benítez S Ramírez Barreto ME 《Waste management (New York, N.Y.)》2008,28(Z1):S21-S26
Integrated waste management systems are one of the greatest challenges for sustainable development. For these systems to be successful, the first step is to carry out waste characterization studies. In this paper are reported the results of a waste characterization study performed in the Campus Mexicali I of the Autonomous University of Baja California (UABC). The aim of this study was to set the basis for implementation of a recovery, reduction and recycling waste management program at the campus. It was found that the campus Mexicali I produces 1ton of solid wastes per day; more than 65% of these wastes are recyclable or potentially recyclable. These results showed that a program for segregation and recycling is feasible on a University Campus. The study also showed that the local market for recyclable waste, under present conditions - number of recycling companies and amounts of recyclables accepted - can absorb all of these wastes. Some alternatives for the potentially recyclables wastes are discussed. Finally some strategies that could be used to reduce waste at the source are discussed as well. 相似文献
963.
2,2‘,4,4’和3,3‘,4,4’—四氯联苯(TCB)对小白鼠体外受精的影响 总被引:2,自引:0,他引:2
采用体外受精技术评价环境污染物2,2',4,4'-和3,3',4,4'-四氯联苯对小白鼠卵母细胞受精能力和2-细胞胚胎发育的毒性作用,实验结果表明:ρ(PCB)=0.1,1.0,10.0mg/mL的2,2',4,4'-和3,3',4,4'-四氯联苯均显著降低小白鼠卵母细胞的受精能力;ρ(PCB)=1.0,10.0mg/mL的2,2',4,4'-和3,3',4,4'-四氯联苯使卵母细胞的退人弦和2-细胞的畸形率显著增加;两种四氯联苯对小白鼠卵母细胞体外受精能力、退化率和2-细胞胚胎的畸形率无统计差异。 相似文献
964.
采用体外受精技术评价环境污染物 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯对小白鼠卵母细胞受精能力和 2 细胞胚胎发育的毒性作用 .实验结果表明 :ρ(PCB) =0 .1,1.0 ,10 .0mg/mL的 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯均显著降低小白鼠卵母细胞的受精能力 ;ρ(PCB) =1.0 ,10 .0mg/mL的 2 ,2’ ,4,4’ 和 3,3’ ,4,4’ 四氯联苯使卵母细胞的退化率和 2 细胞的畸形率显著增加 ;两种四氯联苯对小白鼠卵母细胞体外受精能力、退化率和 2 细胞胚胎的畸形率无统计差异 .表 2参 2 5 相似文献
965.
S.J.Lennon 《生态毒理学报》2001,23(3):34-37
本文概括了12个南部非洲国家电力联营的一体化电力计划(IEP)过程,阐述了使用IEP的长期计划,本文同时也着重讨论了关于未来生产量的决策过程,提出了有利于在南非采纳更清洁技术的角色和措施. 相似文献
966.
Ozen S Darcan S Bayindir P Karasulu E Simsek DG Gurler T 《Environmental monitoring and assessment》2012,184(7):4223-4232
The present study aims to evaluate the effects of pesticides on premature breast development. Forty-five girls (group 1) with premature breast development living in the Menderes region, where greenhouse cultivation is the main income, 16 girls (group 2) living in Izmir city with early puberty, and 33 girls (group 3) who had no signs of puberty were included in the study. Endosulphan 1, endosulphan 2, endosulphan sulphate, methoxychlor, vinclozolin, 4,4-dichlorodiphenyldichlorethylene (DDE), 4,-dichlorodiphenyltrichloroethane (DDT), and 2,4-DDT were evaluated in the serum and adipose tissues of the groups by using a gas chromatography-mass spectrometry method. With the exception of 4,4'-DDE, the pesticides studied were undetectable in the serum and adipose tissue samples. The levels of basal luteinizing hormone (LH), stimulated LH, follicle-stimulating hormone, and the long axis of the uterus and both ovaries were significantly different in the girls who had premature thelarche and detectable 4,4'-DDE levels compared to the girls who had premature thelarche and undetectable 4,4'-DDE levels in serum and adipose tissues. The presence and levels of pesticides in serum and adipose tissues were not related to precocious puberty (PP). The mechanisms that lead to PP may also result in obesity, and obesity may be the underlying cause for PP in this group. 相似文献
967.
Andaloro F Romeo T Renzi M Guerranti C Perra G Consoli P Perzia P Focardi SE 《Environmental monitoring and assessment》2012,184(7):4035-4047
In this paper levels of four (Hg, Cd, Pb, As) potential harmful elements (PHE) were measured in three different environmental matrices (sediments, macroalgae and fishes) from the Aeolian Archipelago and control areas both after 1 and 10 months from a volcanic activity of particular relevance occurred at the end of October 2002. Results were analysed on a multivariate statistical basis with the aim to evaluate: (I) general levels of pollution and increase of PHE due to the event; (II) differences observed among tested matrices in the time of recovery after the occurrence of the critical event; (III) the biological enrichment of PHE along the trophic web produced by the geological event. Results evidenced that volcanic emissions could represent a local source of particular relevance able to determine great enrichments of considered PHE in sediments and biological species. After 10 months from the event, levels in sediments and macroalgae notably decreased, whereas fish species evidenced an increase, principally related to the bioaccumulation phenomena. On the basis of the biological enrichment factors (BEF), major enrichments were evidenced after 1 month whereas, after 10 months, were recorded values reliable to an incomplete recovery. Concerning Cd, the BEF higher levels reported for the species Serranus cabrilla was probably related both to the diet and to the specific detoxification rates of this species. 相似文献
968.
Ahmed F Bibi MH Asaeda T Mitchell CP Ishiga H Fukushima T 《Environmental monitoring and assessment》2012,184(7):4383-4396
Bottom sediments from Lake Jinzai in southwest Japan were analyzed to determine their chemical compositions and to assess the potential for ecological harm by comparison with sediment quality guidelines. The pollution status of lake sediments was evaluated by employing contamination factor (CF), pollution load index (PLI), and geoaccumulation index (I(geo)), focusing on a suite of elements in lakebed and core sediments. Elevated concentrations of As, Pb, Zn, Cu, TOC, N, and P were present in several layers of the upper core and other surface sediments. The elevated metal concentrations are likely related to the fine-grained nature of the sediments, reducing bottom conditions produced by abundant organic matter, and possibly minor non-point anthropogenic sources. Moreover, correlations between the concentrations of trace metals and organic carbon, nitrogen, phosphorus, and iron, suggest that these elements play a role in controlling abundances. Calculated CF, PLI, and I(geo) indicate that the sediments are strongly polluted with respect to As, moderately to strongly polluted with Zn, and moderately polluted with Pb and Cu. Metal concentrations exceed the New York State Department of Environmental Conservation (NYSDEC) lowest effect level and the Canadian Council of Ministers of the Environment (CCME) interim sediment quality guidelines that indicate moderate impact on aquatic organisms in the study area. 相似文献
969.
Grisoli P Rodolfi M Chiara T Zonta LA Dacarro C 《Environmental monitoring and assessment》2012,184(7):4171-4180
The proliferation of air-diffused microorganisms inside public buildings such as schools, hospitals, and universities, is often indicated as a possible health risk. In this research, we have illustrated the results of an investigation realized to determine the health of the air in some university classrooms, both from a microbiological and a microclimatic viewpoint, during the normal didactic activity of direct lessons. The results obtained have been expressed by means of contamination indices, already used in previous works. Very little contamination was recorded in the different phases of air treatment, which underlines the efficiency of the system and of the maintenance protocols. The Global Index of Microbial Contamination (GIMC per cubic meter) showed a value greater than the mean during the heating period (290), while the highest values (95th percentile 1,138.45) were recorded in the period using air conditioning. The index of mesophilic bacterial contamination, though it did not show any significant differences in the various modes of air treatment, showed a mean value (1.34) and the 95th percentile value (4.14), which was greater in the air-conditioning phase. Finally, the mean value of the amplification index underlined a decrease in the microbial contamination in comparison to the outside, while showing situations of increased microbial amplification during the period of simple ventilation (95th percentile 4.27). The 95th percentile values found for GICM in the three sampling periods, however, permitted us to identify the value of GIMC per cubic meter equal to 1,000 as a guide to provide a means of self-monitoring the quality of the air inside the classrooms. From a microclimatic viewpoint, two periods of the year manifested discomfort situations: during the heating phase (winter) and during the simple ventilation phase (spring). The results obtained indicate, therefore, a need to intervene on the environmental parameters, not being able, in this particular case, to intervene on other aspects that influence the microclimate. 相似文献
970.
The study on the performance of a fluorinated polyaniline (PANI) as a fiber coating for solid-phase microextraction (SPME) had been reported and 16 polycyclic aromatic hydrocarbons (PAHs) were selected to evaluate the performance of this fiber. Various parameters including sample volume, extraction temperature, time of desorption and extraction, pH and ionic strength were investigated intensively. A direct comparison between PANI-SPME fiber and commercial fiber was conducted. The results showed that the PANI-SPME coating had high affinity towards target compounds and the proposed method was successfully applied for the detection of real samples: rainfall and Taihu Lake water collected from Southern China. The whole PANI-SPME-GC method offers acceptable accuracy, precision and sensitivity and low detection limits, which is applicable to monitor trace levels of PAHs in real water bodies. 相似文献