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1.
Babay PA Romero Ale EE Itria RF Becquart ET Thiele B Batistoni DA 《Journal of environmental monitoring : JEM》2008,10(4):443-452
In the present work we have developed an analytical methodology for the determination of nonylphenol (NP) and nonylphenol mono- and di-ethoxylates (NP1EO and NP2EO) in water samples. The applicability of this methodology was proved by means of the analysis of environmentally relevant aqueous samples from Buenos Aires. This constitutes a starting point for a rigorous assessment of the incidence of NPnEO surfactants in Argentina, as only very few, qualitative or semi-quantitative data on the occurrence of these compounds in local systems were available up to this time. Enrichment of the analytes was carried out by solid-phase extraction on a C-18 sorbent, followed by elution with ethyl acetate. Normal-phase high performance liquid chromatography on an amino-silica column and fluorescence detection at excitation-emission wavelengths of 230-300 nm were employed for separation and quantification of the analytes. Confirmation of peak assignment in selected real samples was performed by off-line coupling HPLC with GC-MS analysis. A non-polar GC capillary column was used, and a characteristic peak pattern was obtained for the alkyl chain isomers of each ethoxylated homologue and NP. GC-MS analyses yielded in all cases purity levels higher than 80% for the HPLC collected fractions. The elevated concentrations found for the estrogenic metabolites of NPnEO are in accordance with an unrestricted use of this class of non-ionic surfactants in the country. 相似文献
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Haifa RAJHI Daniel PUYOL Mirna C. MARTÍNEZ Emiliano E. DÍAZ José L. SANZ 《Frontiers of Environmental Science & Engineering》2016,10(3):513-521
The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater (four synthetic media, two industrial wastewater, and one domestic effluent) and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogenproducing bacteria, such as Clostridium, and promoted the dominance of acetoclastic- over hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields. 相似文献
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Coupling Flow Analysis With Geochemical and Microbiological Analyses to Assess the Bioremediation Feasibility of a Contaminated Aquifer 下载免费PDF全文
Andrea Gigliuto Emiliano Stopelli Anna Maria Sanangelantoni Aliosha Malcevschi 《补救:环境净化治理成本、技术与工艺杂志》2016,26(3):109-129
An integrated approach combining classic and molecular microbiological methods, “in vitro” bioremediation assays and groundwater numerical modeling, has been established to identify optimized solutions for remediating aquifers contaminated with organic pollutants. Bacteria have been isolated from an aquifer contaminated with toluene and methyl tert‐butyl ether (MTBE), selected for their growth with contaminants as a sole carbon source and identified through 16S rDNA partial sequencing. Successive biodegradation laboratory tests have been performed to determine which chemical conditions were more appropriate for the isolated bacteria to more efficiently oxidize toluene and MTBE. A groundwater model was created using FEFLOW code first to determine the movement of the plume front and second to simulate the impact of the biodegradation processes along the groundwater flow directions based on the bioremediation rates obtained in the laboratory. The results show that this innovative and interdisciplinary model can be used to assist in developing monitoring and remediation plans for cleaning up complex contaminated groundwater sites. This approach successfully combines the identification of the optimum biogeochemical conditions for bacterial biodegradation to occur with the predictability of the development of the process over time, ensuring decisive support in the management of contaminated sites. ©2016 Wiley Periodicals, Inc. 相似文献
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Gloria Antonini Paolo Audisio Emiliano Mancini Alessio De Biase Carlo Tronci Giulia Rossetti Marco Trizzino 《Marine Biology》2010,157(2):371-381
Marine rock-pools, commonly found along the Mediterranean coasts, are isolated patches of habitat characterised by large spatial
and temporal variations. The phylogeography of Calobius quadricollis and C. urbanelliae, two sibling species of moss beetles (Coleoptera, Hydraenidae) inhabiting Italian temporary marine rock-pool ecosystems,
were studied using mitochondrial cytochrome c oxidase subunit I (COI). Our data suggest a strong association between the scored
genetic variability and the geographical distribution of populations sampled for both species. These analyses provided evidences
of episodic species range expansion and fragmentation, recurrent “flush and crash” and bottleneck episodes probably occurring
during the Glacial Cycles. The observed phylogeographical pattern is probably related to the historical and biogeographical
processes of Mediterranean areas, as well as both to the ephemeral habitat tipology and limited dispersal ability of these
beetles. 相似文献
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Emiliano H. Ocampo Jesús D. Nuñez Maximiliano Cledón J. Antonio Baeza 《Marine Biology》2014,161(9):2107-2120
Two ill-explored hypotheses might explain host castration by parasitic pea crabs. The ‘energy drain’ hypothesis states that castration is caused by host-derived nutrient consumption of parasites that ultimately diminishes host-energy intake. The ‘steric interference’ hypothesis states that castration occurs when parasites physically inhibit host reproduction. This study evaluated whether Calyptraeotheres garthi, a pea crab from the southwestern Atlantic, is a parasitic castrator and explored whether the two hypotheses above explain castration in the limpet Crepidula cachimilla. None of three studied limpet species brooded embryos during the reproductive season when infested by mature female pea crabs. Also, limpets of C. cachimilla infested by C. garthi did not reproduce during a 90-day experimental period while crab-free limpets did spawn embryos during this period. Limpets resumed reproduction soon after pea crabs were experimentally removed from their brooding chamber. Thus, C. garthi does castrate limpets, and castration is reversible. Pea crabs ‘steal’ food from limpets, and infested limpets did not modify their feeding behavior to counteract nutrient loss. Thus, infested limpets are expected to ingest less food which provides partial support for the ‘energy drain’ hypothesis. However, the limpet’s body condition increased or was not affected by pea crabs during the breeding season which argues against the same hypothesis. Furthermore, that limpets promptly recovered reproductive activity once pea crabs were experimentally removed, that castration was not induced by the smallest pea crabs in the population (that fill only partially the brooding chamber), and that parasitized limpets did exhibit fully mature ovaries, support the ‘steric interference’ hypothesis explaining parasitic castration. 相似文献
6.
Emiliano Teran-Mantovani 《Sustainability Science》2018,13(3):677-691
Venezuela is well known for its century-old oil economy, which has significantly shaped its social fabrics, territories, and eco-systems. Since 1999, the Bolivarian Revolution has led to important transformations in the context of the ‘Socialism of the 21st century’ project, but the extractivist model has deepened. This situation has created or intensified several ecological distribution conflicts, which have been further exacerbated by an extraordinary national crisis unleashed in the period 2013–2016. In this paper, a geography of the 20 most emblematic and representative socio-environmental conflicts in the period of the Bolivarian Revolution is presented. From a comparative political ecology perspective, this article aims to understand how power relations are expressed through territorial configurations and spatial dynamics of resistance, and what are the implications for sustainability. It is argued that a remarkable new situation of environmental injustice is occurring in this period. Despite the ‘eco-socialist’ discourse raised, the current Petro-State has updated the traditional regime on eco-systems, territories, and human bodies primarily by resorting to the assimilation of socio-environmental conflicts through a strategic distribution policy of oil rents. However, it has maintained a pattern of ecological degradation and social marginalization as an outcome of its economic development model. The current context of crisis has fostered intense territorial disputes and conditions for the emergence of new social actors, practices, scenarios, and geographies linked to underground economies and criminal bands, which complicate an already concerning scenario of unsustainability. The current extractivist model is reaching a breaking point. New commodity frontiers have become a main area of dispute. 相似文献
7.
Sedeño-Díaz Jacinto Elías López-López Eugenia Rodríguez-Romero A. Joseph Leos Karla Fierro Martínez Melissa Tiburcio Sánchez Oscar Emiliano Escobar 《Environmental science and pollution research international》2022,29(41):61630-61642
Environmental Science and Pollution Research - Qanats in the aquifer of the Tehuacán Valley (Mexico) represent an ancient way of using groundwater that is still practiced today. They are used... 相似文献
8.
Luis Gimeno Modesto Sánchez Emiliano Hernández Luis Cana 《Journal of the Air & Waste Management Association (1995)》2013,63(7):811-815
Abstract A multiple regression model was used to describe temporal variations of the concentrations of H+, SO4 2 -, NO3 - and NH4 + in Spanish rainwater. The model included the effects of linear trend, annual cycle, and precipitation quantity simultaneously. The model fit very well for SO4 2 - and NO3 -, with statistical evidence of annual cycle and effect of precipitation quantity for these two ions and for NH4 +, but not for H+. There is no trend for any ion, with the single exception of a decreasing trend for H+ in one of the stations used. 相似文献
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