1,720,994 research outputs found
Chironomid mouthpart deformities as indicator of environmental quality: a case study in Lake Trasimeno (Italy)
No full textThe aim of the present study was to monitor mouthpart deformities of Chironomus plumosus (Insecta-
Diptera) in Lake Trasimeno (2000–2010) in relation with sediment contamination by heavy metals,
which is one of the main causes of deformity induction. In Lake Trasimeno, concentrations of heavy
metals in the investigated littoral zone were low, in comparison with those of the central area. By
contrast, the incidence of deformities was much higher in the littoral station (2006–2009) than in the
central area. In the littoral zone, the deformities progressively decreased and by 2010 reached values
similar to those observed in the central area (2000–2002, 2010). This decrease was mainly due to the
reduction of severe deformities, thus indicating an environmental quality recovery of this littoral sector.
Chemical analysis revealed that the higher incidence of deformities in the littoral zone was not caused
by heavy metal contamination, unless they may have contributed to a joint action with other toxicants.
The present study on Lake Trasimeno provided additional evidence that chironomid mouthpart
deformities can be used in biomonitoring programs to evaluate sediment contamination by toxicants.
Since mouthpart deformities may also be induced by compounds not included in routine chemical
analyses, they may better reflect sediment quality than chemical analysis alone
Factors influencing farmers' decision to enter digestate market
No full textCurrent study evaluated the effect of information on farmers' decision to enter the digestate market and investigated the drivers of individual preferences for this source of organic content. A between subject economic experiment was performed in Sicily (Southern Italy) involving 230 farmers. Through a multiple price list format individual willingness-to-pay (WTP) for digestate and traditional cow manure were elicited. Findings show that providing farmers with information on digestate attributes positively affects respondents’ decision to enter the digestate market. Results provide practical insights to policy makers interested in promoting their decision to enter the digestate market among Mediterranean farmers
Il pavimento della Chiesa di S. Francesco, 1524, Deruta (PG): studio dei materiali costitutivi e della tecnica pittorica
No full textSilica nanoparticles assisted photodegradation of acridine orange in aqueous suspensions
No full texttSilica nanostructured materials are often used as catalyst support but their catalytic role has not beendeeply investigated yet. In the present study, the photocatalytic degradation of acridine orange zincchloride double salt (AO) has been studied using silica nanoparticles (NPs) as catalysts. NPs of differentsize (55 and 146 nm) were prepared by a sol–gel procedure and their surface was modified with aminogroups to investigate the role of the chemical groups linked to the silica surface on the dye degradation.The silica nanomaterials were fully characterized by use of transmission electron microscopy (TEM), zetapotential measurements and UV–vis spectrophotometric methods.The photodegradation experiments were carried out irradiating at 313 or 490 nm for 50 min the aque-ous samples containing the dye and the silica NPs of 55 or 146 nm in diameter. The photocatalyticdegradation of the dye was determined from the decrease of its fluorescence intensity. AO fluorescenceintensity did not change when bare SiO2beads were used as catalysts, whereas an efficient decoloration(up to 58%) was achieved with amino functionalized NPs, with a photodegradation rate constant valueof 0.136 m−1. The data collected from the degradation experiments demonstrated that the functionalgroups on the silica surface have a fundamental role in the efficiency of the degradation processe
Tandem Diels-Alder Reactions of 4-Oxo-2-Cyclopentenyl Acetate. A Facile One-Pot Synthesis of Hydrofluorenones
No full text- …
