Search results for " GAS"

A CO2-gas precursor to the March 2015 Villarrica volcano eruption

2017

We present here the first volcanic gas compositional time-series taken prior to a paroxysmal eruption of Villarrica volcano (Chile). Our gas plume observations were obtained using a fully autonomous Multi-component Gas Analyser System (Multi-GAS) in the 3 month-long phase of escalating volcanic activity that culminated into the 3 March 2015 paroxysm, the largest since 1985. Our results demonstrate a temporal evolution of volcanic plume composition, from low CO$_2$/SO$_2$ ratios (0.65-2.7) during November 2014-January 2015 to CO$_2$/SO$_2$ ratios up to ≈ 9 then after. The H$_2$O/CO$_2$ ratio simultaneously declined to <38 in the same temporal interval. We use results of volatile saturatio…

Spatially resolved SO2 flux emissions from Mt Etna

2016

Abstract We report on a systematic record of SO2 flux emissions from individual vents of Etna volcano (Sicily), which we obtained using a permanent UV camera network. Observations were carried out in summer 2014, a period encompassing two eruptive episodes of the New South East Crater (NSEC) and a fissure‐fed eruption in the upper Valle del Bove. We demonstrate that our vent‐resolved SO2 flux time series allow capturing shifts in activity from one vent to another and contribute to our understanding of Etna's shallow plumbing system structure. We find that the fissure eruption contributed ~50,000 t of SO2 or ~30% of the SO2 emitted by the volcano during the 5 July to 10 August eruptive inter…

Lidar detection of carbon dioxide in volcanic plumes

2015

Volcanic gases give information on magmatic processes. In particular, anomalous releases of carbon dioxide precede volcanic eruptions. Up to now, this gas has been measured in volcanic plumes with conventional measurements that imply the severe risks of local sampling and can last many hours. For these reasons and for the great advantages of laser sensing, the thorough development of volcanic lidar has been undertaken at the Diagnostics and Metrology Laboratory (UTAPRAD-DIM) of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In fact, lidar profiling allows one to scan remotely volcanic plumes in a fast and continuous way, and with high s…

Emission of Bromine and Iodine from Mt. Etna volcano

2005

Constraining fluxes of volcanic bromine and iodine to the atmosphere is important given the significant role these species play in ozone depletion. However, very few such measurements have been made hitherto, such that global volcanic fluxes are poorly constrained. Here we extend the data set of volcanic Br and I degassing by reporting the first measurements of bromine and iodine emissions from Mount Etna. These data were obtained using filter packs and contemporaneous ultraviolet spectroscopic SO2 flux measurements, resulting in time-averaged emission rates of 0.7 kt yr(-1) and 0.01 kt yr(-1) for Br and I, respectively, from April to October 2004, from which we estimate global Br and I flu…

Noble gases in tracking volcanic processess

2007

The expressions able to evaluate the contributions of the three natural sources of helium (e.g., atmosphere,in magma, following the solubility model proposed by Nuccio and Paonita (2001). In particular, variations of He/Ne and He/CO2 ratios have been used to compute the initial and final pressure of an ascending magma (Fig. 2) (Caracausi et alii 2003b, Rizzo et alii 2006). This model was subsequently implemented with S, Cl and F (Aiuppa et alii 2004), providing an useful geochemical tool aimed at giving an early warning for forecasting volcanic eruptions. The high helium flux measured at Mefite d’Ansanto in the Irpinian Apennines, displaying a He isotope composition analogous to that of Mt.…

Towards a new protocol for field measurements of greenhouse gases from wastewater treatment plant

2016

Emissions into the atmosphere of greenhouse gases (GHGs), i.e., carbon dioxide, methane and nitrous oxide from wastewater treatment plants are of increasing concern in the water industry. In order to produce useful and comparable information for monitoring, assessing and reporting GHG emissions from wastewater treatment plants, there is a crescent need for a general accepted methodology. This paper aims at proposing the first protocol for monitoring and accounting GHG emissions from wastewater treatment plants taking into account both direct and internal indirect emissions focusing on sections known to be major responsible of GHG emissions i.e. oxidation tanks and sludge digestion. The main…

Predominance of Type 1 Innate Lymphoid Cells in the Rectal Mucosa of Patients With Non-Celiac Wheat Sensitivity: Reversal After a Wheat-Free Diet.

2016

OBJECTIVES: Non-celiac wheat sensitivity (NCWS) is defined as a reaction to ingested wheat after exclusion of celiac disease and wheat allergy. As its pathogenesis is incompletely understood, we evaluated the inflammatory response in the rectal mucosa of patients with well-defined NCWS. METHODS: The prospective study included 22 patients with irritable bowel syndrome (IBS)-like clinical presentation, diagnosed with NCWS by double-blind placebo-controlled challenge. Eight IBS patients not improving on wheat-free diet were used as controls. Two weeks after oral challenge was performed with 80 grams of wheat daily, cells were isolated from rectal biopsies and thoroughly characterized by fluore…

Discorso turistico-enologico sull’aura in ‘Un’ottima annata’ di Ridley Scott

2023

This essay follows fits into an ongoing project dedicated to highlighting the rhetorical and ideological representations of food and wine in cinema It carries out a semiotic analysis of the film A good year (by Ridley Scott, with the aim of identifying the role that wine plays in it and in the touristic imaginary about it. The essay pursues this goal by facing the issue of authenticity in tour ism as posed by Culler and by reconstructing the implicit aesthetic and touristic theory on which the film may be positioned. Then, it proceeds by getting into a reconstruction of the ideologic role played by the settings and the spaces represented in it. A spatial dialectic among city and country get…

Bacterial communities in stratified humic lakes

2012

Cadmium Metal–Organic Frameworks Based on Ditopic Triazamacrocyclic Linkers: Unusual Structural Features and Selective CO 2 Capture

2017

International audience; Two three-dimensional cadmium metal organic frameworks with general formula [Cd-2(L-1)(H2O)(3)](NO3)(0.7)(HCOO)(0.2)Br-0.1 (Cd2L1, L-1 = 1,4,7-tris(4-carboxybenzy1)-1,4,7-triazacyclononane) and Cd(HL2)(H2O)(2) (CdL2, L-2 = 1,4,7-tris(3-(4-benzoate)prop-2-yn-1-yl)-1,4,7-triazacydononane) based on 1,4,7-triazacyclononane N-functionalized by different arylcarboxylic acids were prepared under solvothermal conditions and characterized by single crystal X-ray analysis and porosity measurements. The crystal structure of Cd2L1 reveals a cationic net with a bcs topology,. and nodes are constituted by dinuclear cadmium complexes, in which each cadmium atom adopts a hexacoordin…