12064 research outputs found
Sort by
Armor Thickness Assessment for the Divertor Tokamak Test Facility (DTT) Divertor Targets
No full textThe Divertor Tokamak Test (DTT) facility is a fusion device under construction in Italy. The mission of DTT is to test alternative divertor concepts under integrated physics and technological conditions that can reliably be extrapolated to DEMO. Due to the plasma core characteristics with relevant edge and scrape-off layer (SOL) parameters and a wall entirely in tungsten (W), DTT will provide an extensive set of information useful to select the most appropriate strategy for the power exhaust in DEMO. Several divertors, which may differ in design or/and technologies or/and poloidal profile, will be tested during the life of the machine. The first divertor to be installed will have to accommodate a multitude of strike points, located at various positions according to the different magnetic configurations, which will be tested in the first operational phases of the machine with the aim to identify the most promising. The first divertor will not test innovative technological solutions but will mainly take advantage of the technologies already qualified for the ITER divertor production. Thus, the entire divertor plasma-facing surface is designed to be used as targets: it will be made of W monoblocks joined on CuCrZr pipes (plasma-facing units, PFUs) similar to the ITER targets. With the purpose to increase the flexibility in operational scenarios by maximizing the allowable thermal load for the PFUs, the possibility of using monoblocks with a plasma side reduced thickness was investigated. By reducing the thickness of the armor, it is possible to limit plastic deformation of the monoblock and to preserve the characteristics of the plasma-facing surface during the component lifetime. A thickness between 3 and 4 mm is compatible both the erosion estimates in the DTT divertor area and the manufacturing constraints and therefore proposed for the DTT PFUs. Several mock-ups based on monoblock design were in the past tested under thermal fatigue, confirming the reliability of the monoblock design and the manufacturing processes, but with larger armor thicknesses (6-8 mm). The experimental verification of the monoblock performance with the proposed reduced thickness has been verified in the GLADIS facility at IPP Garching with a thermal load of 20 MW/m2 applied for 1000 cycles of 10 s. The results showed the absence of plastic deformation and negligible increase in surface roughness
Overview on the Applicability of the ITER/NPP-Like Technologies to the DEMO Plant Electrical System and Promising Alternatives
No full textThe Plant Electrical System (PES) of the European DEMOnstration fusion power plant (DEMO), presently under conceptual design, shall supply power to the loads and deliver net power to the Power Transmission Grid (PTG). Starting from the available requirements, the applicability to DEMO PES of the technologies and design approaches adopted in ITER and nuclear power plants (NPP) has been evaluated. This article presents the results of the survey and proposes alternative solutions to deal with the identified criticalities
Cost, Energy Efficiency, and Environmental Impact Analysis of Orange Juice Pasteurization: Comparing Pulsed Electric Fields with Traditional Thermal Treatment
No full textThis study conducts a comprehensive analysis to assess the feasibility of integrating pulsed electric field technology for pasteurizing orange juice with heat recovery, aiming to offer a sustainable electrical alternative to conventional high-temperature short-time treatment. The evaluation encompasses energy, economic, and sustainability aspects, including cost analysis, energy efficiency, and environmental impact assessment. Despite higher initial costs, the comparison analysis demonstrates significant utility savings and enhanced sustainability with the electric technology compared to the conventional thermal method. An analysis of energetic scenarios identifies the electrical solution with a preheating temperature of 40°C and thermal recovery of 20% as the most energy-efficient and sustainable option, with reduced water consumption and emissions. Overall, the findings suggest that electrical technology holds promise as a viable and environmentally friendly approach to orange juice pasteurization, contributing to the advancement of sustainable food processing practices
Optimizing SnO2 Quantum Dot Precursor Solutions for Perovskite Solar Cells with Reduced Hysteresis
No full textIn recent years, SnO2 quantum dots (QDs) have been widely used for preparing the electron-transport layer within perovskite solar cells (PSCs). However, the fabricated devices exhibit an evident hysteresis unless interlayer materials are introduced to passivate or prevent the formation of trap states at the SnO2–perovskite interface. Herein, the use of the zwitterion 3-(1-pyridinio)-1-propanesulfonate (PPS) as additive inside the SnO2 QDs solution is proposed. The results highlight that the PPS plays a multifunctional role by accelerating the synthesis of the QDs, enhancing the electron transfer and passivating defects at the SnO2–perovskite interface. The resulting PSCs with SnO2 QDs incorporating PPS exhibit a remarkable reduction in hysteresis index (HI) compared to those prepared with thiourea or without any additives. This reduction in HI suggests that PPS serves as a cost-effective alternative additive for SnO2 QDs preparation, eliminating the need for additional interlayers or expensive additives
Innovative Multilayer Electrospun Patches for the Slow Release of Natural Oily Extracts as Dressings to Boost Wound Healing
No full textElectrospinning is an advanced manufacturing strategy used to create innovative medical devices from continuous nanoscale fibers that is endowed with tunable biological, chemical, and physical properties. Innovative medical patches manufactured entirely by electrospinning are discussed in this paper, using a specific plant-derived formulation “1 Primary Wound Dressing©” (1-PWD) as an active pharmaceutical ingredient (API). 1-PWD is composed of neem oil (Azadirachta indica A. Juss.) and the oily extracts of Hypericum perforatum (L.) flowers, according to the formulation patented by the ENEA of proven therapeutic efficacy as wound dressings. The goal of this work is to encapsulate this API and demonstrate that its slow release from an engineered electrospun patch can increase the therapeutic efficacy for wound healing. The prototyped patch is a three-layer core–shell membrane, with a core made of fibers from a 1-PWD-PEO blend, enveloped within two external layers made of medical-grade polycaprolactone (PCL), ensuring mechanical strength and integrity during manipulation. The system was characterized via electron microscopy (SEM) and chemical and contact angle tests. The encapsulation, release, and efficacy of the API were confirmed by FTIR and LC-HRMS and were validated via in vitro toxicology and scratch assays
UAS-based methodology to create digital models of bridges and viaducts
No full textThe use of Unmanned Aerial Systems allows to exploit the aerial photogrammetry technique to obtain high-resolution orthophotos with large images, owing to latest generation payloads. This approach allows to acquire metric data of a structure through the analysis of pairs of stereometric frames. Aerial photogrammetry forms the basis for the creation of point cloud data models used to develop real-time digital replication of objects (or Digital Twins systems)to monitor, analyze and simulate their behavior in the real world, along with Finite Element models for structural analysis, material simulation and design of complex components. In addition, BIM models are developed that integrate detailed information on infrastructure geometry, materials, and performance into a single collaborative 3D model, for improved management and planning during the bridge lifespan. The results obtained by applying these techniques to an Italian bridge will be examined, providing crucial support to experts in infrastructure assessment and monitoring
Ocean surface radiation measurement best practices
No full textOcean surface radiation measurement best practices have been developed as a first step to support the interoperability of radiation measurements across multiple ocean platforms and between land and ocean networks. This document describes the consensus by a working group of radiation measurement experts from land, ocean, and aircraft communities. The scope was limited to broadband shortwave (solar) and longwave (terrestrial infrared) surface irradiance measurements for quantification of the surface radiation budget. Best practices for spectral measurements for biological purposes like photosynthetically active radiation and ocean color are only mentioned briefly to motivate future interactions between the physical surface flux and biological radiation measurement communities. Topics discussed in these best practices include instrument selection, handling of sensors and installation, data quality monitoring, data processing, and calibration. It is recognized that platform and resource limitations may prohibit incorporating all best practices into all measurements and that spatial coverage is also an important motivator for expanding current networks. Thus, one of the key recommendations is to perform interoperability experiments that can help quantify the uncertainty of different practices and lay the groundwork for a multi-tiered global network with a mix of high-accuracy reference stations and lower-cost platforms and practices that can fill in spatial gaps
Solid Foam Insertion to Increase PCM-Based Thermal Energy Storage System Efficiency: Experimental Test and Numerical Simulation of Spherical Macrocapsules
Get PDFPhase change materials (PCMs) are an interesting solution to increase the efficiency of thermal energy storage (TES) systems. The present work explores, with an experimental and computational study, the behavior of a paraffin wax encapsulated in a spherical containment system during the melting and solidification phases. The experimental tests were conducted by immersing the spherical capsule in a thermostatic water bath at different temperatures and measuring the temperatures at four different points inside the capsule. A two-dimensional CFD model of the sphere was then applied to investigate the effect of the insertion of a solid foam into the sphere to increase the system’s responsiveness under demanding conditions. In addition, an analysis of the solidification process considering two different wall materials (HDPE and aluminum) with different thermal conductivity was performed. The results suggest that embedded foams can represent a useful tool to increase the efficiency of a PCM-based TES, but, at the same time, they also highlight that a considerable increase in thermal conductivity is required to achieve significant advantages with respect to pure PCM systems
Sustainable planning: the case study of the Strait of Messina ports
No full textThe energy and environmental policy carried out by the Port System Authority of the Strait (AdSP), in charge of the management of the ports spread along the Strait of Messina, is reported. The Environmental and Energy Planning Document of Port Systems (DEASP, the Italian acronym) is the document explaining the AdSP sustainable strategy to reduce GHG emissions. It defines specific measures, in order to improve energy efficiency in buildings and infrastructures, promote the use of renewable energy in the port area, and confer environmental benefits for the citizens of neighboring territories and port users. The main actions developed are as follows: photovoltaic solar plants and tidal energy systems, electrification of the docks to allow the shore supply of ships, and the construction of a Liquefied Natural Gas (LNG) storage plant to replace more polluting marine fuels, together with awareness campaigns on “green” issues, involving the 3 million users of these ports. Starting from the socio-economic and environmental analysis of the territorial context managed by AdSP, the DEASP analyses all the activities carried out inside port areas and reports the energy consumptions of the concessionaries, in the way to calculate the carbon footprint and develop an environmental sustainable strategy to reduce pollutant emissions. The interventions foreseen are assessed through the cost-benefit analysis and allow reducing the GHG emissions in 2030 up to 46%
PROTO-SPHERA: a magnetic confinement experiment which emulates the jet + torus astrophysical plasmas
No full textThe PROTO-SPHERA experiment, built at the CR-ENEA laboratory in Frascati, was in part inspired by the jet + torus astrophysical plasmas, a rather common morphology in Astrophysics. This paper illustrates how the said plasma morphology can be reproduced in a laboratory with the setup of the PROTO-SPHERA experiment. The experiment as such displayed the appearance and sustainment of a plasma torus around an internal magnetized plasma centerpost (jet) by self-organisation; an entirely unexplored phenomenon to date. The remarkable ideal MHD stability of the PROTO-SPHERA plasma is extremely significant, as it is obtained in a simply connected geometry, inside a perfectly insulating vacuum vessel, and without the need of a nearby stabilizing conducting shell. The concluding sections of this paper deal with application of force-free fields to the Pulsar Wind Nebulae morphology and present an extension of the well-known split-dipole model. Such an extension provides a natural description of the presence of tori around the Pulsar plasma jets. In addition, similarities and differences between the laboratory and the astrophysical jet + torus plasmas are detailed