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31.
The polyethylenimine (PEI) as complexing agent was used to study the complexation-ultrafiltration (CP-UF) process in the selective removal of Cu(II) from Ni(II) contained in aqueous media. Preliminary tests showed that optimal chemical conditions for Cu(II) and Ni(II) complexation by the PEI polymer were pH>6.0 and 8.0, respectively, and polymer/metal weight ratio of 3.0 and 6.0, respectively. The effect of some important operating parameters on process selectivity was studied by performing UF tests at different parameters: pH, polymer/metal weight ratio, transmembrane pressure (TMP), and membrane cut-off in a batch experimental set-up. It was observed that process selectivity was achieved by choosing the pH value for obtaining a preferential copper complexation (pH 6.0), and the polymer/metal ratio needed to bound only the copper ion (3.0). The selective separation by UF tests was performed by using both a laboratory aqueous solution and a real aqueous effluent (water from Emoli torrent, Rende (CS)). The Iris 30 membrane at TMP of 200 kPa (2 bar) for both aqueous media gave the best results. A complete nickel recovery was reached, and copper recovery was the highest for this membrane (94% and 92%). Besides at this pressure, a lower water amount was needed to obtain total nickel recovery by diafiltration. A little higher membrane fouling was obtained by using the river effluent due to the presence of dissolved organic and inorganic matter. 相似文献
32.
Cioffi R De Stefano L Lamanna R Montagnaro F Santoro L Senatore S Zarrelli A 《Chemosphere》2008,70(6):1068-1076
This paper deals with the application of mechanochemistry to model systems composed of alumina or silica artificially contaminated with n-C16H34. The mechanochemical treatment was carried out by means of a ring mill for times ranging from 10 to 40h. Thermogravimetry and infrared and nuclear magnetic resonance spectroscopies were used for the characterization of the mechanochemical products. The results have indicated that, in the case of alumina, almost all the contaminant n-C16H34 undergoes a complex oxidative reaction path whose end products are strongly held on the surface. These end products are most likely made of crosslinked, partially oxidized hydrocarbon chains bond to the solid surface via COO(-) groups. In the case of silica, the hydrocarbon undergoes a different, equally complex reaction path, but to a lower extent. In this case the end products are most probably carbonylic compounds and graphitic carbon. Then, for both solid matrices, the mechanochemical treatment promotes significant modification of the chemical nature of the polluting hydrocarbon with end products much more difficult to remove from the surface. As the systems studied are models of sites contaminated by aliphatic hydrocarbon, the results are worthy of consideration in relation to the mobility of the contaminants in the environment. 相似文献
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34.
Specchiulli Antonietta Scirocco Tommaso D’Adamo Raffaele Cilenti Lucrezia Fabbrocini Adele Cassin Daniele Penna Pierluigi Renzi Monia Bastianoni Simone 《Journal of Coastal Conservation》2016,20(5):363-374
Phytoplankton and benthic vegetation biomass undergoes spatial-temporal changes in relation to their life cycle, but also to meteorological conditions, physical-chemical variables, organic input and internal dynamism. The main aim of this work was to observe the effect of all environmental variables on the vegetative dynamic process in a protected zone of a Mediterranean costal lagoon (Lesina lagoon, SE Italy). Seven samplings were performed from 2010 to 2012 at 30 sites for nutrient and chlorophyll analyses, while TOC measurements and wet biomass evaluation were performed at 10 sites. Temperature, salinity and oxygen saturation were also measured by multiparametric probe and a visual census for vegetation was performed. Sites close to freshwater inflow were characterized by lower temperature and salinity, and high nitrate, with maxima of 191.05 μM in May 2010 and more than 250 μM in October 2010. Silicates drastically decreased from May 2010 (87.57 μM) to July 2010 (6.15 μM) and increased again in October (74.99 μM). Chl a concentrations were not on average higher than 6 mg m?3, but peaks of 20 mg m?3 were observed during May 2011 and May 2012. Benthic vegetation wet biomass collected in 2010 was approximately twice that collected in 2012, with a maximum of 27,554 g m?2 and a dominance of macroalgae (70 % in May 2010 and 40 % in August 2010). During period 2010, a simultaneous and drastic decreasing of both mean values of wet biomass and chl a was observed from May to October 2010. During period 2012 a shift of vegetation biomass was shown from May (phytoplankton prevalence) to August 2012, with angiosperm prevalence (more than 30 %). 相似文献
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Motta Oriana Pironti Concetta Ricciardi Maria Rostagno Chiara Bolzacchini Ezio Ferrero Luca Cucciniello Raffaele Proto Antonio 《Environmental science and pollution research international》2022,29(20):29391-29398
Environmental Science and Pollution Research - The most important parameter to obtain an appropriate preservation condition of museum environments concerns the indoor air quality. The exposure of... 相似文献
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de Oliveira Maria Rayane Correia de Lima Silva Maria Gabriely Alcântara Isabel Sousa Filho Jaime Ribeiro Tintino Cícera Datiane de Morais Oliveira Magalhães Francisco Ernani Alves Martins Anita Oliveira Brito Pereira Bezerra Pessoa Renata Torres Duarte Antonia Eliene da Costa José Galberto Martins de Lima Sidney Gonçalo Coutinho Henrique Douglas Melo Capasso Raffaele de Menezes Irwin Rose Alencar 《Environment, Development and Sustainability》2021,23(10):14958-14981
Environment, Development and Sustainability - This work aimed to analyze the chemical composition and evaluate the anti-inflammatory and antinociceptive properties of the essential oil obtained... 相似文献
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Alessandro Costagliola Franco Roperto Domenico Benedetto Aniello Anastasio Raffaele Marrone Antonella Perillo Valeria Russo Serenella Papparella Orlando Paciello 《Environmental science and pollution research international》2014,21(9):6252-6257
Nitrate and nitrite are toxicants that have become increasingly significant environmental chemicals. Increase in environmental distribution of nitrogenous compounds, especially in surface and ground water, has been attributed to the intensive use of nitrate as agricultural fertilizers and to increasing amounts of nitrogenous wastes produced by municipalities, industries, and feedlots. The purpose of this study is to illustrate a fatal nitrate toxicosis in cattle associated with the consumption of fennels (Foeniculum vulgare). Fifteen cows from the same farm suddenly developed weakness, muscular tremors, respiratory distress, and finally convulsions. The affected animals died within 24 to 48 h from the onset of the clinical signs. Five cows underwent a complete post-mortem examination. In all examined animals, gross lesions included presence of dark unclotted blood around the nostrils and the anal region, moderate inflammation of the gastrointestinal mucosa, and brown discoloration of the skeletal muscles and kidneys. The histological examination showed tubular degeneration and congestion of glomerular vessels in the kidney. Toxicological analysis detected nitrates at 4 672.2 ppm in the fennels used to feed the animals. The source of exposure to nitrates was identified in the fennels. The fennels were grown in a polluted area of the Campania region in southern Italy and distributed in a public market for human consumption. The waste from the sale of the fennels was fed to the cows. The accumulation of nitrates in some vegetables poses a risk not only for animal health but also for human and environmental safety. 相似文献
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Christopher Kuzdas Benjamin Warner Arnim Wiek Mariel Yglesias Raffaele Vignola Alonso Ramírez-Cover 《Local Environment》2016,21(11):1387-1408
There is a need for specific knowledge of what people can do to mitigate harmful water conflicts. This need is evident in the rural dry tropics of Central America where people face climate change impacts, inefficient water management, and social tension. To address this need, we investigated why some local water conflicts escalated to violence and why other potential conflicts were avoided in Guanacaste Province, Costa Rica. We used interviews, focus groups, and a stakeholder workshop to analyse five cases. We found that violent actions only occurred when rural groups opposed government agencies in settings without mediating leadership. With one exception in a circumstance aggravated over many years, water users did not take violent action against competing water users. Distrust, which has been formed by legacies of ineffective rural stakeholder engagement, diminished the credibility of water-related information used in decision processes and thus prolonged conflicts. Active community-based groups respected by both rural constituencies and government agencies helped some people avoid difficult conflicts. Self-organised groups in other areas struggled to address disputes in settings with contested property rights, high socio-economic inequality, and low human capital. Using insights from Guanacaste, we outline practical conflict mitigation strategies fitted to a range of local water governance contexts found in rural Central America. Results suggest the need for incorporating certain types of peace-building processes in water management and development. The study provides a foundation for policy-makers, water managers, and other stakeholders to more effectively manage water disputes and avoid harmful conflicts in challenging regions. 相似文献
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Elisa Costa Veronica Piazza Chiara Gambardella Roberto Moresco Ermelinda Prato Francesca Biandolino Daniele Cassin Margherita Botter Daniela Maurizio Raffaele D’Adamo Adele Fabbrocini Marco Faimali Francesca Garaventa 《Environmental science and pollution research international》2016,23(13):12755-12769
The Mar Piccolo of Taranto (Ionian Sea, Southern Italy) is a semi-enclosed and strongly polluted basin. For decades, it has been subjected to different anthropogenic impacts. These stressors caused severe sediments contamination with high concentration of different pollutants (PAHs, PCB, heavy metals). In order to assess the current status of sediments contamination, an ecotoxicological investigation combined with chemical analysis (heavy metals, PAH, and PCB) has been performed. In order to derive ecologically relevant conclusions, a multiorganisms and multiend-points approach has been applied, exposing organisms from different trophic levels to elutriate and whole sediment. The battery of bioassays consists of a microalgal growth inhibition test (Dunaliella tertiolecta), acute and sublethal assays (end-points: mortality, immobilization and swimming speed alteration) on crustaceans larvae and juveniles, and rotifers (Amphibalanus amphitrite, Artemia salina, Corophium insidiosum and Brachionus plicatilis), and embryotoxicity test on echinoderms (Paracentrotus lividus). Considering the high levels of sediment contamination highlighted from chemical analysis, an unexpected very low toxic effect was observed, even considering the sublethal end-point (larval swimming speed alteration). The results of this study suggest a very complex contaminants dynamic in the Mar Piccolo sediments that, despite a strong level of contamination, seems to not affect in a proportional manner the biological compartment. 相似文献
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Pironti Concetta Ricciardi Maria Proto Antonio Cucciniello Raffaele Fiorentino Antonino Fiorillo Rosa Motta Oriana 《Environmental science and pollution research international》2022,29(20):29385-29390
Environmental Science and Pollution Research - In this study, we evaluated indoor air quality to highlight the effects of environmental pollution in the field of cultural heritage. In particular,... 相似文献