106 research outputs found

    Seismic Hazard Mapping inside the Project SIGMA

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    The Project SIGMA (Sistema Integrato di sensori in ambiente cloud per la Gestione Multirischio Avanzata) arises from the fields of Information and Communications Technologies (ICT) and advanced applications for the control, monitoring and management of high-risk processes of natural and social origin. SIGMA is a multilevel architecture whose main aim is the acquisition, integration and processing of heterogeneous data from different sources (seismic, volcanic, meteorologic, hydric, pluvial, car traffic, marine traffic, and so on) to manage and elaborate risk mitigation strategies which are important for the emergency management planning. Within the several experimental activities included in the project, there is the designing and realization of a prototype of application platform specialized to provide the operating procedures and software to the public administrations and the industrial companies, for constantly monitoring both the anthropic and natural phenomena in Sicily. In this framework, of course, the seismic risk analysis plays a very important role since Sicily is one of the Italian regions with high seismic risk. Seismic risk assessment may be approached in two different ways: i) as average seismic risk of the buildings and facilities in question during the period considered, combining the vulnerability of different building types and the seismic hazard for the site, which are then expressed in terms of the effects of the events derived from an earthquake catalogue that exceed a specified threshold during a given period; ii) as estimated damage of the buildings and the critical facilities using a scenario input described in terms of the source parameters of the hypocenter as location, magnitude, and so on. Here we deal with the hazard calculation through the code CRISIS (Ordaz, Aguilar and Arboleda) and with the code PROSCEN (PRObabilistic SCENario, [Rotondi and Zonno, 2010]) to obtain earthquake scenario to be used in the latter approach. Indeed, an earthquake scenario is a planning tool that helps decision makers to visualize the specific impact of an earthquake based on the scientific knowledge. An earthquake scenario creates a picture that the members of community can recognize and, at the same time, improves the communication between the scientific, emergency management and policy communities to seismic risk reduction

    Exploiting the Condensation Reactions of Acetophenone to Engineer Carbon-Encapsulated Nb2O5 Nanocrystals for High-Performance Li and Na Energy Storage Systems

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    Efficient synthetic methods to produce high‐performance electrode‐active materials are crucial for developing energy storage devices for large‐scale applications, such as hybrid supercapacitors (HSCs). Here, an effective approach to obtain controllable carbon‐encapsulated T‐Nb2O5 nanocrystals (NCs) is presented, based on the solvothermal treatment of NbCl5 in acetophenone. Two separate condensation reactions of acetophenone generate an intimate and homogeneous mixture of Nb2O5 particles and 1,3,5‐triphenylbenzene (TPB), which acts as a unique carbon precursor. The electrochemical performance of the resulting composites as anode electrode materials can be tuned by varying the Nb2O5/TPB ratio. Remarkable performances are achieved for Li‐ion and Na‐ion energy storage systems at high charge–discharge rates (specific capacities of ≈90 mAh g−1 at 100 C rate for lithium and ≈125 mAh g−1 at 20 C for sodium). High energy and power densities are also achieved with Li‐ and Na‐ion HSC devices constructed by using the Nb2O5/C composites as anode and activated carbon (YPF‐50) as cathode, demonstrating the excellent electrochemical properties of the materials synthesized with this approach.Peer Reviewe

    High-Entropy Spinel Oxides Produced via Sol-Gel and Electrospinning and Their Evaluation as Anodes in Li-Ion Batteries

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    In the last few years, high-entropy oxides (HEOs), a new class of single-phase solid solution materials, have attracted growing interest in both academic research and industry for their great potential in a broad range of applications. This work investigates the possibility of producing pure single-phase HEOs with spinel structure (HESOs) under milder conditions (shorter heat treatments at lower temperatures) than standard solid-state techniques, thus reducing the environmental impact. For this purpose, a large set of HESOs was prepared via sol-gel and electrospinning (by using two different polymers). Ten different equimolar combinations of five metals were considered, and the influence of the synthesis method and conditions on the microstructure, morphology and crystalline phase purity of the produced HESOs was investigated by a combination of characterization techniques. On the other hand, the presence of specific metals, such as copper, lead to the formation of minority secondary phase(s). Finally, two representative pure single-phase HESOs were preliminarily evaluated as active anode materials in lithium-ion batteries and possible strategies to enhance their rate capability and cyclability were proposed and successfully implemented. The approaches introduced here can be extensively applied for the optimization of HEO properties targeting different applications.Italian Ministry of University and Research (MUR)Peer Reviewe

    Real-time urban seismic network and structural monitoring by means of accelerometric sensors: Application to the historic buildings of Catania (Italy)

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    A real-time urban seismic network for seismic and structural health monitoring is being installed in the city of Catania (Sicily, Italy). The 27 monitoring stations, specifically designed and assembled, equipped with a low-noise 3-axial MEMS accelerometer, are located in 23 high exposure and vulnerability buildings. In this paper we present the characteristics of the monitoring station and of the network. In case of strong seismic events, the system will provide shake maps to the emergency management centre, and will allow to assess the health conditions of the monitored buildings. The network is conceived to be further expandable over the whole historical city centre of the city of Catania.PublishedMilan, Italy1IT. Reti di monitoraggi
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