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Potential of teff as alternative crop for Mediterranean farming systems: Effect of genotype and mowing time on forage yield and quality
Full text linkThe introduction of alternative/innovative crops in the current Mediterranean cropping systems is a promising strategy to cope with climate change effects, which are threatening the food and feed security of that geographic area. Thanks to its large environmental adaptability and good nutritive value for humans (grains) and animals (biomass), teff is an excellent candidate to perform its role as alternative plant species for cereal/forage farming systems. However, the adoption of a “new” crop requires information about the adaptation to the target environment as well as details on the best management practices to apply. Very little knowledge is available regarding the performance of teff under Mediterranean climatic conditions. The aim of this study was to assess the effect of genotype and mowing time on the biomass yield (dry matter, DM) and proximate composition of teff (including the first regrowth). Grain yield potential was also evaluated. The study was carried out during two consecutive years in central Italy. Two different experiments were conducted in adjacent fields to gain information on both forage and grain potential of the crop. In both trials, six teff genotypes were used (namely T6, T7, T8, T11, T13 and T14). Plant height, forage yield and quality were assessed in different growth stages: flag leaf completely unrolled, booting, and heading. The regrowth of the first cut mowed at booting stage was also evaluated. Our study demonstrated that teff has potential as forage and grain crop under Mediterranean climatic conditions. Considering the total biomass production, teff genotypes yielded from 7 t DM ha−1 to 11 t DM ha−1. If used as feed source, the best harvesting time is heading (GS: 57) since it allows to maximize both biomass yield and crude protein (CP) content. The teff accessions which deserve to be deeply explored as forage types were T8 and T14 (5–6 t DM ha−1, with 150–160 g CP kg−1 DM), while T6, T7 and T13 were good grain producers (0.8–1.2 t ha−1)
Socio economic perspectives on fusion power for a sustainable future energy system
No full textIn the global effort towards the mitigation of climate change, low-carbon electricity generating technologies play a pivotal role. Nuclear fusion stands as a highly promising option for carbon-free electricity generation in a sustainable, reliable, affordable and socially acceptable future energy system. The EUROfusion work package “Socio Economic Studies” (WPSES) on fusion conducts research aimed at identifying social and economic conditions that can effectively support fusion deployment in future energy markets. Placing nuclear fusion in the broader context of energy and climate issues, the SES research explores fusion as an energy technology contributing to sustainable energy production for the future society. Because of the cross-cutting nature of the research, SES studies can provide decision-makers with scientific evidence relevant for shaping appropriate strategies in favour of fusion. This paper aims to offer the scientific community a thorough overview of EUROfusion SES research, addressing a gap in the current literature
Optimization of paper characterization procedures for cultural heritage
Full text linkLa conservazione dei Beni Culturali è di importanza fondamentale per sostenere l’identità nazionale. Trattamenti con le radiazioni ionizzanti vengono utilizzati in tutto il mondo per la conservazione di opere d’arte costituite da materiali di origine naturale (carta, legno, pergamena) ma in Italia non sono ancora accettati del tutto, probabilmente a causa della non corretta conoscenza degli effetti indotti dalla radiazione sul manufatto. Da questo punto di vista, lo studio approfondito di questi effetti secondari e delle condizioni di irraggiamento che permettono di minimizzarli riveste un ruolo centrale. In questo report sono descritte procedure convalidate di caratterizzazione fisico chimica della carta, prima e dopo irraggiamento, con diverse tecniche sperimentali.Conservation and preservation of Cultural Heritage is of paramount importance to maintain the national identity. Ionizing radiation treatments are worldwide applied for conservation of artworks made from materials of organic origin (paper, wood, parchment, etc.) but in Italy they are not fully accepted probably due to the incorrect knowledge of the radiation induced effects on the artifacts. In this regard, the investigation of these secondary effects and of their minimization plays a key role. In this report, established procedures for the physico-chemical characterization of paper, before
Reinforcing Efficiency of Recycled Carbon Fiber PLA Filament Suitable for Additive Manufacturing
Full text linkThe use of 3D printing technology for manufacturing new products based on sustainable materials enables one to take advantage of secondary raw materials derived from recycling. This work investigates the structural performances of 3D printing composite filaments based on polylactic acid (PLA), as a matrix, reinforced by recycled carbon fiber (rCF). Carbon fibers were recovered from industrial scraps by a patented thermal process and used to produce thermoplastic composite filaments for additive manufacturing without any additional treatment and additives. The influence of the recovered carbon fiber (rCF) content on the thermal properties, mechanical properties and microstructure of the composites was studied in the range of 3–20 wt%. The recorded TGA curves exhibited a one-stage weight loss within the temperature range 290–380 °C for all samples and the residual rCF content was in good agreement with the theoretical fiber loading. The Young modulus of the extruded filaments strongly increased below a critical content (5 wt%), while at higher content the improvement was reduced. An increase in the storage modulus of 54% compared to neat PLA 3D printed sample resulted in a printed specimen with a higher rCF content. SEM images highlighted a strong rCF prevailing alignment in the direction of the extrusion flow, creating almost unidirectional reinforcement inside the filament. These findings suggest that homogeneous composite filaments reinforced with well-dispersed recycled CF without additional chemical modification and additives are suitable materials for additive manufacturing. The effect of rCF topological distribution within the material on the mechanical performances has been discussed, highlighting that the isolated fibers could efficiently transfer loads with respect to the percolated 3D network and have been correlated with the microstructure
Uniform Tendency of Surface Dipoles Across Silicon Doping Levels and Types of H-Terminated Surfaces
No full textThe termination of surface-dangling bonds on silicon through hydrogen atoms, also known as Si–H, can achieve chemical passivation and reduce surface states in the electronic bandgap, thus altering electronic properties. Through a comprehensive study of doping levels (1014–1020 cm−3) and types (n and p), a consistent surface dipole trend induced by Si–H termination is discovered. It is achieved by redistributing surface charges and establishing thermal equilibrium with the chemical bond. To resolve this, the surface work function, surface electron affinity, and the energy difference between the valence band and the Fermi level are measured by employing the Kelvin probe, X-ray photoelectron spectroscopy, and photoelectron yield spectroscopy methods. These findings are further validated through ab initio simulations. This finding has immense implications not only for eliminating electronic defects at semiconductor interfaces, which is crucial in microelectronics but also for developing and engineering hybrid interfaces and heterojunctions with controlled electronic properties
COREDIV simulations of D and D-T high current-high power Baseline pulses in JET-ITER like wall
Full text linkThe two best performing pulses of the so called ITER-Baseline scenario (I p = 3.5 MA and P in ≈ 35 MW) of JET-ITER like wall, one in deuterium (D) the other in deuterium-tritium (D-T) plasma are examined and compared in this study. Generally, the D-T Baseline pulses exhibit an electron density level higher than the D pulses and the plasma energy is higher than in the comparable D pulses by up to 20%, reaching about 12 MJ in the pulse studied here. In contrast with the D pulses, the D-T pulses are often characterised by the increase in time of the radiated power in the mantle region (0.70 < ρ < 0.95), which may lead to the loss of the edge localised mode activity when the threshold H-L transition power is approached and to the subsequent plasma disruption due to excessive radiation. In this study we try to identify the physical mechanisms responsible for this behaviour using the available experimental data (principally the total radiated power from the bolometry) and the results of the fluid COREDIV model (1D in the core, 2D in the scrape-off-layer (SOL)), self-consistent with respect to core-SOL and also to main plasma-impurities. In fact, the loss of power caused by impurity radiation affects the temperature profile and finally the power to the divertor plate. The electron density and temperature profiles are numerically reconstructed as well as the radiated power density profiles, indicating no major difference in impurity transport in D and D-T. Indeed, the impurity transport coefficients used in COREDIV to match the experimental radiated power profiles are similar in the two pulses. The computed tungsten sources and densities are lower in the D-T pulse and the divertor impurity retention capability is a little better in the D-T pulse, indicatinga stronger collisional drag force in the SOL. The higher electron density and the broadening of its profile are the main cause of the observed increase of the radiated power in the D-T pulse
Monitoraggio e analisi di rischio ecologico. Misura 1.44: Innovazione, sviluppo e sostenibilità nel settore della pesca professionale campana. Progetto ISSPA - "Innovazione, Sviluppo e Sostenibilità nel settore della Pesca e dell'Acquacoltura per la Regione Campania"
Full text linkNel triennio 2020-2023, nell’ambito del progetto ISSPA (Innovazione, Sviluppo e Sostenibilità nel settore della Pesca e dell’Acquacoltura per la Regione Campania) è stato eseguito uno studio volto alla valorizzazione della pesca professionale nel territorio campano. Le attività svolte dal dipartimento SSPT (Dipartimento Sostenibilità, circolarità e adattamento al cambiamento climatico dei Sistemi Produttivi e Territoriali) dell’ENEA (Agenzia nazionale per le nuove tecnologie, l'energia e lo sviluppo economico sostenibile) sono state condotte in collaborazione con l’ARPAC (Agenzia Regionale per la Protezione Ambientale della Campania) con l’obiettivo di quantificare e mappare i potenziali rischi ecologici ed ecotossicologici derivanti dall’esposizione degli organismi acquatici a stressori chimici presenti nelle acque e nei sedimenti dei sistemi lotici e lentici della regione. A tale scopo sono stati individuati e caratterizzati 50 siti di interesse, rappresentativi dei corpi idrici campani di maggior pregio faunistico ed ecologico. Le concentrazioni dei principali contaminati inorganici (elementi potenzialmente tossici, PTEs) e organici, (idrocarburi di origine petrolifera e composti fenolici) sono state analizzate nei campioni di acqua e sedimento. Inoltre, è stata condotta una valutazione degli effetti ecotossicologici e, per il sedimento, è stata eseguita anche la caratterizzazione granulometrica. I risultati ottenuti mostrano che i livelli di rischio nelle aree monitorate dei corpi idrici della regione Campania non sono preoccupanti, rendendo tali siti compatibili con le attività di pesca e acquacoltura. Tuttavia, alcune evidenze di effetti legati alla contaminazione chimica hanno rivelato la necessità di approfondire ulteriormente lo studio sul comportamento dei contaminanti in miscela e sulle loro interazioni con l’ambiente al fine di valutare correttamente i potenziali impatti sugli ecosistemi.From 2020 to 2023, within the scope of the ISSPA project (Innovation, Development, and Sustainability in the Fisheries and Aquaculture Sector for the Campania region), a study to improve the professional fishing sector of the Campania region was conducted. SSPT department (Sustainability, Circularity and Adaptation to Climate Change of Production and Territorial Systems Department) of ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development) carried out activities in collaboration with ARPAC (Regional Agency for Environmental Protection of Campania), to assess potential ecological and ecotoxicological risks associated with the exposure of aquatic organisms to chemical stressors in the waters and sediments of the region's lotic and lentic systems. As part of this study, 50 sites of interest were identified and characterized to represent Campania's water bodies with the greatest faunal and ecological value. Water and sediment samples from these sites were analyzed for concentrations of main inorganic (PTEs - Potentially toxic elements) and organic (petroleum hydrocarbons and phenolic compounds) contaminants. Additionally, an assessment of ecotoxicological effects and particle size characterization were conducted for the sediment samples. The findings indicate that risk levels in the monitored water bodies of the Campania region are not significant, allowing these sites to be compatible with fishing and aquaculture activities. However, some evidence of effects related to chemical contamination of environmental matrices has underscored the need for further investigations concerning the behavior of contaminant mixtures and their interactions with the environment to assess accurately potential impacts on ecosystems
P2-Type Na0.84Li0.1Ni0.27Mn0.63O2-Layered Oxide Na-Ion Battery Cathode: Structural Insights and Electrochemical Compatibility with Room-Temperature Ionic Liquids
Full text linkModern technologies that can replace state-of-the-art Li-ion batteries (LIBs), such as Na-ion batteries (NIBs), are currently driving new advancements in energy storage research. Developing functional active materials having sustainable features and enhanced performances able to assess their exploitation in the large-scale market represents a major challenge. Rationally designed P2-type layered transition metal (TM) oxides can enable high-energy NIB cathodes, where the tailored composition directly tunes the electrochemical and structural properties. Such positive electrodes need stable electrolytes, and exploration of unconventional room-temperature ionic liquid (RTIL)-based formulations paves the route toward safer options to flammable organic solvents. Notwithstanding the fact that Li+ doping in these materials has been proposed as a viable strategy to improve structural issues, an in-depth understanding of structure-property relationship as well as electrochemical testing with innovative RTIL-based electrolytes is still missing. Herein, we propose the solid-state synthesis of P2-Na0.84Li0.1Ni0.27Mn0.63O2 (NLNMO) cathode material, which exhibits promising structural reversibility and superior capacity retention upon cycling when tested in combination with RTIL-based electrolytes (EMI-, PYR14-, and N1114-FSI) compared to the standard NaClO4/PC. As unveiled from DFT calculations, lattice integrity is ensured by the reduced Jahn-Teller distortion upon Na removal exerted by Mn4+ and Li+ sublattices, while the good redox reversibility is mainly associated with the electrochemically active Ni2+/Ni3+/Ni4+ series burdening the charge compensation upon desodiation. By declaring the electrochemical compatibility of the P2-NLNMO cathode with three RTIL-based electrolytes and dissecting the role of Li/Ni/Mn sublattices in determining the electrochemical behavior, our comprehensive study enlightens the potential application of this electrode/electrolyte setup for future high-energy NIB prototype cells
Applying Computational Spectroscopy Methods to Raman Spectra of Dicationic, Imidazolium-Based, Ionic Liquids
No full textStudying ionic liquids (ILs) through computational methods is one of the ways to accelerate progress in the design of novel and potentially green materials optimized for task-specific applications. Therefore, it is essential to develop simple and cost-effective computational procedures that are able to replicate and predict experimental data. Among these, spectroscopic measurements are of particular relevance since they are often implicated in structure-property relationships, especially in the infrared spectral region, where characteristic absorption and scattering processes due to molecular vibrations are ultimately influenced by the surrounding environment in the condensed phase. In this frame, we validate, vis-à-vis experimental data, an efficient theoretical method to compute the Raman spectra in the liquid phase of four especially synthesized dicationic ionic liquids and to assess the conformational cation/anion contributions to the experimental bands. The computational procedure is based on the assessment of the most probable conformations as evaluated by a computational protocol involving both molecular dynamics and ab initio methods
ATEP: an advanced transport model for energetic particles
Full text linkIn this paper we report on the implementation and verification of a phase-space resolved energetic particle (EP) transport model. It is based on a first-principle theoretical framework, i.e. the system of non-linear gyrokinetic equations and the related transport equations. Its focus is primarily directed toward understanding the meso-scale character of EPs and its consequences. Compared to the conventional description of thermal radial transport via a one-dimensional radial diffusion equation, the newly developed model is three-dimensional using canonical constants-of-motion (CoM) variables. The model does not assume diffusive processes to be dominant a priori, instead the EP fluxes are self-consistently calculated and directly evolved in CoM space. We use the EP-Stability workflow and the HAGIS code to determine the phase space fluxes explicitly either in the limit of constant mode amplitudes or an energy-conserving quasi-linear model. As an application of the model the transport of neutral-beam-generated EPs due to a toroidal Alfvén eigenmode in an ITER plasma is investigated. As there are no sources and collisions taken into account so far (for an extension of the model see the companion paper (Meng et al 2024 Nucl. Fusion accepted)), the results cannot be considered as an exhaustive study, but rather as a practical demonstration of the conceptual framework on the way to a comprehensive reduced description of burning plasmas