Search results for " pollution"
showing 10 items of 1010 documents
Formaldehyde: Catalytic Oxidation as a Promising Soft Way of Elimination
2013
International audience; Compared to other molecules such as benzene, toluene, xylene, and chlorinated compounds, the catalytic oxidation of formaldehyde has been studied rarely. However, standards for the emission level of this pollutant will become more restrictive because of its extreme toxicity even at very low concentrations in air. As a consequence, the development of a highly efficient process for its selective elimination is needed. Complete catalytic oxidation of formaldehyde into CO2 and H2O using noble-metal-based catalysts is a promising method to convert this pollutant at room temperature, making this process energetically attractive from an industrial point of view. However, th…
Electrochemical treatment of aqueous solutions containing one or many organic pollutants at boron doped diamond anodes. Theoretical modeling and expe…
2012
The electrochemical oxidation of organics in water at boron doped diamonds (BDD) was experimentally investigated with the aim to discuss the correlations among the conversion of the pollutants and the instantaneous current efficiency ICE with the operative conditions. A simple theoretical model previously developed for the oxidation of oxalic acid accounting for the cases of mass transfer control, oxidation reaction control and mixed kinetic regimes was adopted and extended to challenge its predictive capability in the case of organics of different nature and in systems with more pollutants. A quite good agreement, between theoretical predictions and experimental data pertaining to the elec…
Vulnerability maps pollution to hydrocarbon and urban waste pollution in seawater intrusion areas
2004
De acuerdo con un proyecto nacional promovido por el Grupo Nacional Italiano para la Protección contra Riesgos Hidrogeológicos han sido publicados los mapas de vulnerabilidad (1:50.000) de parte del Territorio Italiano, particularmente algunos mapas de Sicilia: Montes Iblei, Moadonie, Sicani y el Monte Etna. Estos mapas se han vuelto documentos públicos para el manejo local del agua subterránea. Algunos fenómenos muy peligrosos han sido reportados en algunas áreas de Sicilia. Intervenciones antrópicas han creado basureros de residuos tóxicos sobre áreas vulnerables. Esta investigación explica las ventajas del uso de mapas de vulnerabilidad en estudio de tipos peligrosos de contaminación par…
Air pollution perception in ten countries during the COVID-19 pandemic.
2021
As largely documented in the literature, the stark restrictions enforced worldwide in 2020 to curb the COVID-19 pandemic also curtailed the production of air pollutants to some extent. This study investigates the perception of the air pollution as assessed by individuals located in ten countries: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the USA. The perceptions towards air quality were evaluated by employing an online survey administered in May 2020. Participants (N = 9394) in the ten countries expressed their opinions according to a Likert-scale response. A reduction in pollutant concentration was clearly perceived, albeit to a different extent, by all …
Numerical Modelling of the Urban Climate
1988
Three-dimensional numerical models of the urban climate have been developed in order to simulate climatic changes and air pollution in urban regions due to anthropogenic activities. Two versions are presented. Model A covers mesoscale γ and uses the roughness length to characterize surface structure. The microscale version B approximates the actual urban build-up by rectangular blocks. Model A results agree reasonably well with observations. For complex building structures, the microscale model must be applied. Model B results on neutral flow and pollutant transport within a particular building configuration are discussed.
Nuit(s) et Territoire(s) : pratiques nocturnes, sciences sociales diurnes ?
2014
National audience
Preliminary insights about the treatment of contaminated marine sediments by means of bioslurry reactor: Process evaluation and microbiological chara…
2022
Abstract Contaminated marine sediments represent a critical threat towards human health and ecosystems, since they constitute a potential reservoir of toxic compounds release. In the present study, a bioslurry reactor was studied for the treatment of real marine sediments contaminated by petroleum hydrocarbons. The experimental campaign was divided in two periods: in the first period, microcosm trials were carried out to achieve useful indicators for biological hydrocarbon removal from sediments. The microcosm trials highlighted that the inoculum of halotolerant allochthonous bacteria provided the highest performance followed by autochthonous biomass. Based on the achieved results, in the s…
Hydrocarbons removal from real marine sediments: Analysis of degradation pathways and microbial community development during bioslurry treatment
2022
In this study, real marine sediments polluted by petroleum compounds were treated by means of a bioslurry pilot scale reactor. The treatment performance was evaluated by measuring the removal of total petroleum hydrocarbon (TPH), coupled to further analyses required to understand the mechanisms involved in the biodegradation process. The maximum TPH-removal efficiency reached 86 % at the end of experiments. Moreover, high throughput 16S RNA gene sequencing was used to describe the microbiome composition in sediment prior to, and after, bioslurry treatment, in order to identify the taxa mostly entailed in the TPH removal process. The raw sediment was mostly colonized by members of Sulfurimon…
Ecotoxicity assessment of natural attenuation effects at a historical dumping site in the western Baltic Sea.
2005
During the late 1950s and early 1960s of the past century, industrial waste material highly enriched in various contaminants (heavy metals, PAHs) was dumped in the inner Mecklenburg Bay, western Baltic Sea. Large-scale shifts in the spatial distribution of heavy metals in surface sediments were mapped by geochemical monitoring in the mid-1980s and 12 years later in 1997. A further study in 2001 was designed to investigate the small-scale spatial distribution of contaminants inside, on top of, and around the historical dumping ground and to examine possible effects to benthic organisms (Arctica islandica, microbiological toxicity tests). The site is located within an area characterized by a …
Pesticide monitoring in the basin of Llobregat River (Catalonia, Spain) and comparison with historical data.
2014
Through an extensive sampling in the Llobregat River basin, the presence of 50 currently used pesticides in water, sediment, and biota was assessed. Pesticides were detected primarily in water (up to 56% of the analytes), whereas their presence in sediments was more intermittent, and in biota was scarce. Those at high concentrations in water were the benzimidazoles (carbendazim in 22% of the samples up to 697ngL-1), the organophosphorus (malathion in 54% of the samples up to 320ngL-1), and the ureas (diuron in 54% of the samples up to 159ngL-1). However, this pattern differed in sediments and biota, which were contaminated primarily with organophosphorus (higher Kow) (chlorpyrifos 93% of se…