12064 research outputs found
Sort by
Anti-inflammatory effect of a pomegranate extract on LPS-stimulated HepG2 cells
No full textPomegranate is an important source of bioactive molecules with proven beneficial effects on human health. The aim of this study was to investigate the potential anti-inflammatory effect of a pomegranate extract (PE), obtained from the whole fruit and previously characterized by Reversed Phase-Ultra High-Pressure Liquid Chromatography-High Resolution Mass Spectrometry (RP-UHPLC–HRMS), on HepG2 human hepatocellular carcinoma cells challenged with the lipopolysaccharide (LPS). In LPS-treated cells (1 μg/ml, 24h), the PE treatment (administered at the non-cytotoxic dose of 1 μg/ml, 24h) induced a significant reduction of three key pro-inflammatory cytokines, i.e. interleukin-8 (IL-8), interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α), at both gene expression (as assayed by real-time PCR) and secretion levels (by Enzyme-linked Immunosorbent Assay, ELISA). Although further in vivo studies are needed to prove its efficacy, this preliminary in vitro study suggests that the PE might be useful for ameliorating liver inflammation
Design and Assessment of the New CIRCE-THETIS Facility for the Development of Heavy Liquid Metal Cooled Fast Reactors
No full textWithin the roadmap for the technological development of Generation IV reactors, the HORIZON2020 European Union–funded Partitioning And Transmuter Research Initiative in a Collaborative Innovation Action (PATRICIA) project was launched to support innovative solutions for the development of the Multi-purpose hYbrid Research Reactor for High-tech Applications (MYRRHA) accelerator-driven system concept and lead fast reactor technologies in general. The ENEA contributes to the project by involving the experimental infrastructures of the Brasimone Research Center (Italy). In particular, a large-scale pool-type facility named CIRColazione Eutettico (CIRCE), using lead-bismuth eutectic as the primary coolant and pressurized water as the secondary fluid, is under refurbishment with the implementation of a novel test section (TS) named Thermal-hydraulic HElical Tubes Innovative System (THETIS) to be installed in the CIRCE main vessel. The new TS will include a vertical mechanical pump for primary coolant circulation and a new prototypical helical coil steam generator (HCSG). This steam generator concept turns out to be very promising for nuclear power plants since the helical geometry is very compact and it assures high power removed, taking up a minimum amount of space. Accordingly, with the aims of the project, the experimental tests in CIRCE-THETIS will focus on (1) investigating the thermal-hydraulic behavior of the system in steady-state operation (forced circulation regime) during operational and accidental transients (postulated scenarios) and in a natural circulation regime considering as heat sink the HCSG (acting as a decay heat removal system) and the reactor vessel auxiliary cooling system in stand-alone or coupled operation and (2) characterizing the performance of the HCSG. The present work presents the layout of the CIRCE-THETIS facility at the end of the final design phase, describing in detail the main components of the TS, along with the instrumentation installed. Focus will be given to the HCSG mock-up, for which pretest analyses using the system thermal-hydraulic code RELAP5/Mod3.3 and a computational fluid dynamics code have been carried out to support the design of the component and to evaluate its thermal-hydraulic performance under the operative conditions foreseen during the experiments
Presentation and Preliminary Test of APRIL: A New Facility for the Characterization of Antipermeation Coatings for Fission and Fusion Applications
No full textAntipermeation and anticorrosion coatings are being developed to reduce tritium permeation from liquid metal [LiPb of the water-cooled lithium-lead breeding blanket and Pb for lead-cooled fast reactors (LFRs)] to primary heat transfer systems. The facility APRIL (Alumina-coating for tritium Permeation Reduction for Innovative LFR) was designed and installed at ENEA Brasimone R.C. to characterize the permeation reduction factor (PRF) of the candidate coatings in static conditions. In the current configuration, APRIL is composed of three pipes, closed at one end, that simulate the heat exchangers of the ALFRED LFR. Two of the pipes are coated with 3 μm of alumina with pulsed laser deposition techniques, the reference method for a fission reactor. The third pipe is uncoated. During the tests, all the pipes are filled with pressurized steam at 100 bar and 480°C, the steam generator condition of the ALFRED LFR. The tests are made in the gas phase; indeed, the three pipes are installed in a chamber filled with helium with a known concentration of deuterium that simulates tritium. Deuterium permeates inside the pipes, allowing for the evaluation of the PRF by means of the ratio between the measured permeated flux in the uncoated pipe and in the coated ones. A first test with 0.5% of deuterium was carried out and the evaluated PRF was about 13.5
The energy renovation pathway to ZEB in Italy: Analysis of typical buildings and methodological aspects
No full textThe evolution towards high-energy efficient buildings is one of the most important challenges today and is in line with the objectives set by the new European Directive on the Energy Performance of Buildings (EPBD) which provides for the decarbonization of entire building stock by 2050. The study starts from the analysis of the current regulatory framework in Europe and Italy, highlighting the lack of homogeneity in the methods of transposition of European directives by the Member States already at the "nearly zero energy buildings" level (nZEB). Starting from these considerations, the critical analysis of the European and Italian context highlights the need to overcome the standards currently in force and investigate new perspectives for the design of high-efficient buildings in the direction of "zero energy and zero emissions". For this reason, two residential and office buildings typologies are examined to confirm whether the net Zero Energy Building (ZEB) objective can be achieved through the legislation in force in Italy, starting from nZEB level. The study analyses the energy balance through dynamic simulations and evaluates energy needs of buildings and renewable energy production in order to verify the compliance to ZEB target, on yearly and monthly basis
Circularity assessment in buildings and built environment: An integrated multiscale framework
No full textCircular transition requires systematic interventions in the built environment, particularly at the urban level, to close resource loops locally. The adoption of a design-operational approach focused on the life-cycle perspective and circularity, in line with the Green Building Approach, at the same time responds to resource scarcity and cuts CO2 emissions in the regeneration and integration of urban settlements. In this view, the dimension of the urban neighbourhood offers an ideal field of experimentation to test and scale up circular strategies and solutions, starting from the building scale. The contribution reports the results of an ongoing research whose aim is to propose a methodology to identify basic characteristics and performances allowing a neighbourhood to be defined as circular, and to promote their spread through design both in regeneration and new construction. Thus, the research addresses an important gap due to the limited number of studies on circularity metrics at the neighbourhood scale. From a methodological point of view, the research analyses a selection of case studies and, in parallel, existing circularity metrics at different levels, systematizing them with a set of indicators coming from sustainability protocols at the neighbourhood scale. The research therefore defines an integrated multiscale framework supporting circular design and assessment, valid at the building level but also - in a multiscale perspective - at the neighbourhood level, aiming to develop a support tool for public administrations and designers
Energy flexibility potential associated with thermal uses in prototypes of Italian single-family buildings
No full textThe transition towards renewable distributed generation and the electrification of consumption will increasingly enhance energy flexibility strategies aimed at promoting self-consumption, energy sharing, and optimizing grid operation. Residential thermal loads can also contribute to these objectives, and this study aims to provide new insights in this regard. The study, based on dynamic load simulation, extends to three types of building-system setups (existing, renovated, and nearly zero-energy) in three climatic contexts (Milan, Rome, and Palermo). Characterization of the flexibility potential associated with building thermal inertia is based on appropriate indicators (Flexibility Index and Peak Load Reduction Factor) comparing consumption profiles associated with two types of internal temperature setpoint control: standard and flexible. The latter is modelled predictively, based on a penalty curve and predicted climatic conditions. Two penalty datasets are considered to represent the perspectives of the energy distributor (DSO) and the operator of a Renewable Energy Community (CER) with photovoltaic installations. The results show how the technological characteristics of building structures can influence the building's flexibility potential. The greatest benefits are observed during the heating phase and in renovated buildings, which manage to ensure good load shifting capability and significant peak load reduction (up to 60-80%). It is interesting to note that in more efficient buildings, a large portion of flexibility potential can be achieved through energy efficiency solutions, even without flexible control
Embedding Resilience to Climate Change and Natural Hazards in Smart Services
No full textNatural and man-made hazards are increasingly threatening our cities and communities. It is therefore imperative to provide readily accessible information and know how to public authorities and stakeholders on the possible impacts that such hazards might induce on different exposed elements, as well as on the opportunities of implementing resilience strategies to mitigate impacts, to adapt to long term threats and to promptly recover and thrive in the aftermath of crisis. The on-going digital transition is posing an unprecedented opportunity towards that; cities can be digitally empowered with low-cost sensors, smart collaborative technologies, interoperable platforms that, thanks to open-science algorithms and applications, allow democratizing access to data and information and fostering knowledge. In this work, we envisage resilience as a view of each smart city dimension; sensors, Key Performance Indicators KPIs and platforms produced for and by vertical components of smart cities are reinterpreted with resilience lenses and support decision makers with smart services that are also instrumental in supporting resilience enhancement. This paper moves some first steps towards that by revising and identifying parallels in policies, frameworks and standards related to smart and resilient cities and by presenting preliminary implementations in Camerino Municipality
A Deep Learning Approach for User-Centric Clustering in Cell-Free Massive MIMO Systems
No full textContrary to conventional massive MIMO cellular configurations plagued by inter-cell interference, cell-free massive MIMO systems distribute network resources across the coverage area, enabling users to connect with multiple access points (APs) and boosting both system capacity and fairness across user. In such systems, one critical functionality is the association between APs and users: determining the optimal association is indeed a combinatorial problem of prohibitive complexity. In this paper, a solution based on deep learning is thus proposed to solve the user clustering problem aimed at maximizing the sum spectral efficiency while controlling the number of active connections. The proposed solution can scale effectively with the number of users, leveraging long short-term memory cells to operate without the need for retraining. Numerical results show the effectiveness of the proposed solution, even in the presence of imperfect channel state information due to pilot contamination
Passive Daytime Radiative Cooling (PDRC): the nanohybrid approach
No full textA set of new nanohybrid polymeric formulations containing silicon compounds (like T8 silsesquioxanes or SiC nanoparticles) and small organic molecules (like azulene) have been deposited on adhesive aluminium tape, characterized and exposed to the outdoor environment of Casaccia (Rome), monitoring their temperature. Results of the first month of external campaign show that they exhibit PDRC effects
An Open-Source Optimal Network Reconfiguration Tool for Improving Distribution Grid Reliability
No full textThe paper presents the structure of an open-source software tool that can solve an Optimal Network Reconfiguration problem for a distribution grid. The problem includes kinship constraints that permit to fully represent the logics which are behind the principal distribution automation schemes adopted by Distributor System Operators to deal with the fault detection, isolation and recovery function. The algorithm is structured to be fully open-source and it is developed on a Python-based environment. The adopted network models are also open-source and based on the Open-DSS software. Results obtained on the model of a realistically sized MV primary distribution network are shown