Search results for "Pact"
showing 10 items of 2355 documents
First observational evidence for the CO<sub>2</sub>-driven origin of Stromboli's major explosions
2011
Abstract. We report on the first detection of CO2 flux precursors of the till now unforecastable "major" explosions that intermittently occur at Stromboli volcano (Italy). An automated survey of the crater plume emissions in the period 2006–2010, during which 12 such explosions happened, demonstrated that these events are systematically preceded by a brief phase of increasing CO2/SO2 weight ratio (up to >40) and CO2 flux (>1300 t d−1) with respect to the time-averaged values of 3.7 and ~500 t d−1 typical for standard Stromboli's activity. These signals are best explained by the accumulation of CO2-rich gas at a discontinuity of the plumbing system (decreasing CO2 emission at the surfa…
Atmospheric sources and sinks of volcanogenic elements in a basaltic volcano (Etna, Italy)
2011
Abstract This study reports on the first quantitative assessment of the geochemical cycling of volcanogenic elements, from their atmospheric release to their deposition back to the ground. Etna’s emissions and atmospheric depositions were characterised for more than 2 years, providing data on major and trace element abundance in both volcanic aerosols and bulk depositions. Volcanic aerosols were collected from 2004 to 2007, at the summit vents by conventional filtration techniques. Precipitation was collected, from 2006 to 2007, in five rain gauges, at various altitudes around the summit craters. Analytical results for volcanic aerosols showed that the dominant anions were S, Cl, and F, and…
Crater Gas Emissions and the Magma Feeding System of Stromboli Volcano
2013
Quiescent and explosive magma degassing at Stromboli volcano sustains high-temperature crater gas venting and a permanent volcanic plume which constitute key sources of information on the magma supply and dynamics, the physical processes controlling the explosive activity and, more broadly, the volcano feeding system. The chemical composition and the mass output of these crater emissions (gases, trace metals, radioactive isotopes) were measured using different methodologies: within-plume airborne measurements, ground-based plume filtering, and/or in situ analysis, remote UV and open-path Fourier transform infrared absorption spectroscopy. The results obtained, summarized in this paper, demo…
Mercury content and speciation in the Phlegrean Fields volcanic complex: evidence from hydrothermal system and fumaroles
2009
Abstract Mercury is outstanding among the global environmental pollutants of continuing concern. Although degassing of active volcanic areas represents an important natural source of mercury into the atmosphere, still little is known about the amount and behaviour of Hg in volcanic aquifers, especially regarding its chemical speciation. In order to assess the importance of mercury emissions from active volcanoes, thermal waters were sampled in the area surrounding La Solfatara, Pozzuoli bay. This is the most active zone of the Phlegrean Fields complex (coastal area north–west of Naples), with intense hydrothermal activity at present day. Studied groundwaters show total Hg (THg) concentratio…
Life Cycle Assessment for Supporting Eco-Design: The Case Study of Sodium–Nickel Chloride Cells
2021
The European Union is moving towards a sustainable, decarbonized, and circular economy. It has identified seven key value chains in which to intervene, with the battery and vehicle value chain being one of them. Thus, actions and strategies for the sustainability of batteries need to be developed. Since Life Cycle Assessment (LCA) is a strategic tool for evaluating environmental sustainability, this paper investigates its application to two configurations of a sodium–nickel chloride cell (planar and tubular), focusing on the active material and the anode, with the purpose of identifying the configuration characterized by the lowest environmental impacts. The results, based on a “from cradle…
Life cycle assessment of storage systems: the case study of a sodium/nickel chloride battery
2014
This study assesses the energy and environmental impacts of sodium/nickel chloride batteries, one of the emerging battery technologies for energy storage and smart grids. The analysis was conducted using the Life Cycle Assessment methodology according to the standards of the ISO 14040 series. The study system was one sodium/nickel cell battery providing electric storage for a photovoltaic system, and the manufacturing, operation, and end-of-life steps were analysed. The results indicated that the operation step has the greatest energy impact (55-70% of the total), with the manufacturing step, particularly cell manufacturing, contributing the greatest environmental impact (>60% of the total)…
An integrated energy simulation and life cycle assessment to measure the operational and embodied energy of a Mediterranean net zero energy building
2022
Abstract Net Zero Energy Buildings can play a key role in reducing the energy use, greenhouse gas emissions and the use of natural resources associated to the built environment. It is widely recognized that in low energy building a shift in relevance may occur from the operational to the embodied impacts. However, building performance assessment focus mostly on the operational phase and on primary energy consumption. This study aims to assess the energy and environmental impacts of a residential net zero energy building expanding the analysis to the full life cycle and to a wide range of environmental impact categories. The methodological approach integrates a non-steady state building ener…
Long-term optical variability of high-mass X-ray binaries. II. Spectroscopy
2016
We present the results of our monitoring program to study the long-term variability of the Halpha line in high-mass X-ray binaries. We have carried out the most complete optical spectroscopic study of the global properties of high-mass X-ray binaries so far with the analysis of more than 1100 spectra of 20 sources. Our aim is to characterise the optical variability timescales and study the interaction between the neutron star and the accreting material. Our results can be summarised as follows: i) we find that Be/X-ray binaries with narrow orbits are more variable than systems with long orbital periods, ii) we show that a Keplerian distribution of the gas particles provides a good descripti…
The Impact of the New Rural Cooperative Medical Scheme on Township Hospitals' Utilization and Income Structure in Weifang Prefecture, China
2017
The New Rural Cooperative Medical Scheme was gradually introduced from 2003 in China. This paper is based on a representative survey of 24 randomly selected township hospitals in Weifang prefecture over the period 2000-2008. Using a generalized form of differences-in-differences model, it aims to assess the effect of the reform on the utilization and income structure of the township hospitals. The estimations provide three main results linked to the effects of the New Rural Cooperative Medical Scheme on the behavior of the key stakeholders (households, health care providers and Health Bureau). Firstly, the reform had positive impacts on the utilization of township hospitals, particularly on…
Benign cementoblastoma: A case report
2006
In the past the benign cementoblastoma was recognized in the World Health Organization?s classification of odontogenic tumours as one of the cementoma neoplasias. Recently the benign cementoblastoma is included into ?Mesenchyme and/or odontogenic ectomesenchyme, with or without odontogenic epithelium? odontogenic tumours. Benign cementoblastoma has characteristic radiologic and microscopic features and it appears to be fused to the tooth roots. Symptoms may be totally absent, and when they do occur, pain and swelling are frequent findings. The final diagnosis is usually made histopathologically, but the clinical diagnosis is comparatively easy if it is examined radiographically. The tumour …