Search results for "CHIMICA"
showing 10 items of 4450 documents
Selenium around Etna Volcano, Italy
2010
Humans are attracted by the fertile properties of volcanic soils and currently around 10% of the world population lives within active volcanic areas. Volcanoes emit significantly amounts of potentially toxic elements such as selenium (Se), even in the absence of obvious volcanic activity. Although Se is an essential element for humans, ingestion of an excess amount of Se can produce adverse effects. Mt. Etna, the biggest volcano in Europe, is persistently active for the last 200,000 years and one of the most intensely monitored volcanoes. We have studied selenium in rainwater and soils from Mt Etna volcano. Bulk depositions were collected from April 2006 to December 2007, using a network of…
Rapid sensing of volcanic SO₂ fluxes using a dual ultraviolet camera system: new techniques and measurements at Southern Italian volcanoes
2012
Volatiles carry crucial information on pre- to sin-eruptive processes at active volcanoes. Measurements of gas emission rates (crater plumes, fumaroles, diffuse soil degassing) therefore improve our understanding of degassing processes and subsurface magmatic and hydrothermal conditions, and contribute to eruption forecasting. Recent technological developments in spectroscopy have allowed, over the last 30 years, the remote sensing of magmatic volatile emissions from quiescent and erupting degassing volcanoes. These data-sets have contributed to discovering cyclic gas flux components due to periodic magma supply and replenishment in magma storage zones, and/or timescales of magma migration …
Are the Salinelle mud volcanoes threatening human health or are anthropogenic activities threatening the Salinelle mud volcanoes?
2012
Passive samplers were used to measure the atmospheric concentrations of SO2 naturally emitted at three volcanoes in Italy (Etna, Vulcano and Stromboli) and of H2S naturally emitted at three volcanic/geothermal areas in Greece (Milos, Santorini and Nisyros). The measured concentrations and dispersion patterns varied with the strength of the source (open conduits or fumaroles), the meteorological conditions and the area topography. At Etna, Vulcano and Stromboli, SO2 concentrations reach values that are dangerous to people affected by bronchial asthma or lung diseases (>1000 μg m−3). H2S values measured at Nisyros also exceed the limit considered safe for the same group of people (>3000 μg m−…
Formaldehyde and total aldehydes in indoor air of public environments by voltammetry
2014
The proposed method involves active sampling, where a sampling pump is used to pull air through a solution and voltammetric analysis of the obtained solutions. No interferences have been observed. In addition, very little sample preparation is required. Analyses were performed in 19 indoor stations and one in outdoor. Measurements were carried out on University environments: Museum of Chemistry, Zoological Museum, libraries, laboratories, corridors, meeting rooms, photocopying room, machine shop and terrace. Formaldehyde concentrations in analyzed samples ranged from 2.6 to 85 μg m-3 (median = 32 μg m-3), while the sum of others aldehydes ranged from 2 to 25 μg m-3 (median =2.4 μg m-3). In …
Electrochemical sensor for phosphate ions based on laser scriber reduced graphene oxide
2022
This preliminary work shows a new and innovative way to produce laser scribed reduced graphene oxide (LSGO) electrodes using different porous substrates (ranging from paper to plastic and fabric). The obtained electrodes were also tested as electrochemical sensors towards the detection of phosphate ions in water. To obtain the electrodes, a water suspension of GO was filtered on top of substrate (such as Whatman® filter paper) and a complete sensor was obtained from its reduction using a CO2 laser. The electrode is composed of working and counter electrodes made of LSGO and a reference electrode of a Ag/AgCl obtained by using a commercial AgCl conductive paste. Phosphate ions were detected …
Micro-determination of dithiocarbamates in pesticide formulations using voltammetry
2013
Abstract The purpose of this work was to develop a reliable method for the micro-determination of dithiocarbamates (mancozeb, maneb, propineb, nabam, Na(CH3)2DTC, zineb, ziram, ferbam and thiram) in pesticide formulations for agriculture using adsorptive stripping voltammetry (AdSV). The accuracy of analytical method was valued by analyzing simulate formulation samples prepared by us with known amounts of active ingredients. In addition, the applicability of the AdSV procedure for the analysis of DTCs and EBDTCs in micro-samples was evaluated by estimating its recoveries from spiked commercial formulate samples. The accuracy, valuated as recovery percentage ranged between 85% and 97%. The p…
Voltammetric determination of platinum in perfusate and blood: Preliminary data on pharmacokinetic study of arterial infusion with oxaliplatin
2012
Abstract Because Platinum Group Elements have found widespread use in catalytic converters in cars and as chemotherapeutic agent, interest in the development of reliable analytical methods is carried out in order to monitor these analita in humans to protect the citizen's health. Considering that information on the levels of many trace elements in biological matrices is scarce and for many non-essential elements, baseline levels in the population, and especially in those particularly exposed to the risk are lacking, in this paper we optimize an analytical method for biological matrices, using a voltammetric technique to measure the concentration of Pt in blood and perfusate. The amount of P…
Quantification of Platinum in Edible Mushrooms Using Voltammetric Techniques
2021
Edible mushrooms are a food source with interesting nutritional values. The chief objective of this research was to develop a consistent method for the quantitative ultra-trace analysis of Pt in mushrooms, which is complex because it cannot be readily quantified by common analytical procedures. This research is one of the first analytical methods to establish Pt amount in these vegetables. In this research, 28 different edible mushroom samples from Italy were investigated. Determination of Pt in mushrooms was completed using Differential Pulse Voltammetry (DPV). In this study, we applied the standard addition method because there are no certified reference mushrooms containing platinum grou…
Consolidation tests on the graffiti of the Steri’s prison with nanotechnological Ca(OH)2 dispersed in iso-propanol
2009
The combination of weathering and human activities often induce pyhisicochemical alteration on the surface of wall paintings. One of the most still largely used restoration techniques for these works of art, is based on the application of organic polymers. Due to their ability to stick detached and powdered pigments,these products provide an immediate consolidating effects. Unfortunately, both their aging and their pyhisicochemical incompatibility with the inorganic support can have serious consequences also causing further damage to the work of art. In this paper a new technological approach is presented based on the use of Ca(OH)2 nanoparticles dispersed in isopropanol. Some applicative t…
Gli affreschi provenienti dalle terme romane di Reggio Calabria. Dalla conoscenza al restauro
2023
The frescoes at marine thermae discovered in 1886 during the excavation of the small thermal complex dating between the 1th and 3rd century AD, and located on the seafront of Reggio Calabria, have been collected already collapsed. They are currently part of the permanent exhibition of the National Archaeological Museum of Reggio Calabria. This paper illustrates the results of the restoration intervention, carried out in the form of an educational activity in the context of an agreement signed between the MarRC and the University of Calabria, and the results of the diagnostic investigations carried out by the IPCF-CNR of Messina and the STEBICEF department of the University of Palermo.