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The tunable resonant IC antenna concept and its design for DTT experiment
No full textThe intrinsic poor loading of Ion Cyclotron (IC) plasma-facing antennas makes the use of Tuning and Matching Systems (TMSs) a necessity. The antenna plus TMS is a resonant system; in the TMS and access lines high voltages (tens of kV) must be accounted for in the unavoidable unmatched part of the feeding lines. In this work, we propose and test an innovative type of IC launcher; it is based on achieving resonance of the self-standing antenna, i.e. without the TMS. A mechanical full-metal tuning mechanism is described and demonstrated to allow wide-band operation. A systematic analysis of possible antenna topologies has led to identifying a structure that can allow good impedance matching along with compliance with maximum electric field constraints. Most of the design is carried out using a simplified plasma and a commercial analysis tool and then validated with a realistic plasma using TOPICA code
Re-discovering Prunus fruit varieties as antiangiogenic agents by metabolomic and bioinformatic approach
No full textIn this work, a comparative chemical-biological study of nine plum varieties (Prunus domestica L. and Prunus salicina Lindl.) with two commercial ones was carried out to improve their cultivation and use in the agri-food chain. The chemical quali-quantitative fingerprint by HR-Orbitrap/ESI-MS showed similar profiles, being ‘Rossa Casa Velasco’ the richest in phenols and anthocyanins. All the extracts were investigated for their in vitro antioxidant as well as antiangiogenic activity by two in vivo models, chick chorioallantoic membrane and zebrafish embryos. Among investigated varieties ‘Scarrafona’, ‘Rusticano’, ‘Marisa’, ‘Rossa Casa Velasco’, ‘Verdone’, and ‘Sangue di Drago’ showed the best antiangiogenic activities (30–50 % inhibition). Finally, the chemical/biological datasets processed with a bioinformatic approach revealed that a large group of flavonoids, procyanidins, and anthocyanins significantly correlated with all the three antioxidant tests (DPPH, FRAP, and ABTS), while quinic acid and icariside F2 resulted positively correlated with CAM at both 100 and 200 μg/egg
Testing the effect of semi-transparent spectrally selective thin film photovoltaics for agrivoltaic application: A multi-experimental and multi-specific approach
Get PDFThe integration of photovoltaic technologies within the agricultural framework, known as agrivoltaics, emerges as a promising and sustainable solution to meet the growing global demands for energy and food production. This innovative technology enables the simultaneous utilization of sunlight for both photovoltaics (PV) and photosynthesis. A key challenge in agrivoltaic research involves identifying technologies applicable to a wide range of plant species and diverse geographic regions. To address this challenge, we adopt a multi-experimental and multi-species approach to assess the viability of semi-transparent, spectrally selective thin-film silicon PV technology. Our findings demonstrate compatibility with crop production in controlled environments for both plants and algae. Notably, selective thin-film PV exhibits the potential to enhance crop yields and serves as a photo-protectant. We observe that plant and algal growth increases beneath the selective PV film when supplemented with appropriate diffuse light in the growth environment. Conversely, in situations where light intensity exceeds optimal levels for plant growth, the selective PV film provides a photo-protective effect. These results suggest potential supplementary benefits of employing this technology in regions characterized by excessive light irradiation, where it can contribute to healthy plant growth
Metric f(R) gravity with dynamical dark energy as a scenario for the Hubble tension
Get PDFWe introduce a theoretical framework to interpret the Hubble tension, based on the combination of a metric f(R) gravity with a dynamical dark energy contribution. The modified gravity provides the non-minimally coupled scalar field responsible for the proper scaling of the Hubble constant, in order to accommodate for the local SNIa pantheon+ data and Planck measurements. The dynamical dark energy source, which exhibits a phantom divide line separating the low redshift quintessence regime (−1 < w < −1/3) from the phantom contribution (w < −1) in the early Universe, guarantees the absence of tachyonic instabilities at low redshift. The resulting H0(z) profile rapidly approaches the Planck value, with a plateau behaviour for z ≿ 5. In this scenario, the Hubble tension emerges as a low redshift effect, which can be in principle tested by comparing SNIa predictions with far sources, like QUASARS and gamma ray bursts
Pattern in water-related birds reveals a shift in biomass between mature and mowed reedbeds: evidence from a coastal wetland
No full textIn Mediterranean wetlands, Phragmites australis reed beds are often intensively managed through mowing. These practices may improve wetland heterogeneity with contrasting effects on many reed-bed related birds. Here, we analyzed the habitat selection of a guild of six water-related breeding birds in a patchy managed wetland, where reed-bed mowing was periodically carried out. We reported data about the habitat use and selection of species on five different habitat patches (non-managed mature and managed by mowing reed-beds, rush-beds, open waters, and ecotones), both considering species abundance and biomass. Moreover, we focused on differences between non-managed/mature reed-beds and managed (mowed) ones. As expected, all the species showed a significant difference in frequency of habitat use, both considering abundance and biomass. As expected, rails (Eurasian coot, Moorhen), Mallard and Little grebe selected open waters, Reed warbler selected reed beds and Cetti’s warbler selected ecotones. Detrended Correspondence Analysis (DCA) performed on abundance values confirmed the link among habitats and species. However, when performing DCA on biomasses, we showed a shift of the largest species toward mowed reed-beds. The direct comparisons between mature and managed (mowed) reed-beds, using the Abundance/Biomass comparisons, highlighted the difference in abundance and biomass when comparing these habitat patches: in mature reed-beds the biomass curve was located below the abundance one (high frequency in abundance of low biomass birds, as warblers), whilst in mowed reed-beds the biomass curve was located above the abundance one (comparable high frequency of large biomass species, such as ducks, rails and grebe). Although our data suggest reed-bed mowing may disadvantage small passerines, we observed this type of management may favor large body species, providing them a higher availability of shelters and breeding sites
Characterization of recycled end-of-life rubber tire filled with black slag
No full textTo date, discarded tires are reused in many applications, however, because of the enormous quantity decommissioned annually, it is essential to continue researching new recycling methods as well as applications to reduce waste and preserve new resources. In the present study, a simple recycling technology of end-of-life tire (ELT) powder is proposed, and the influence of steel slag as filler is assessed. Europe produces about 7 Mt of steel slag annually, and although most of it is reused as an artificial aggregate, about 15% is still landfilled. Also in the case of steel slag, the study of new applications is mandatory so that the combination of these two waste materials, in a 100% recycled composite fits across different industrial sectors facing the same environmental issue. It was found that the leaching of the slag incorporated in the rubber matrix is reduced and that the ELT powder recycled by this technology gives rise to a well-cohesive material. A good rubber-filler interaction was found by swelling test and differential scanning calorimetry (DSC) analysis. The slag reduces the friction coefficient and increases the thermal conductivity. The experimental results showed how some properties of recycled ELT can be improved by adding the steel slag
A Review on the Valorization of Lignocellulosic Biomass for Succinic Acid Production: Strengths and Weaknesses
No full textBio-based succinic acid production holds great promise for the process sustainability through the use of renewable resources such as lignocellulosic biomass and the use of microorganisms that can utilize CO2 in fermentation processes. A critical review of the latest findings on succinic acid production from lignocellulosic biomass was discussed, by highlighting all the key aspects of optimization processes at different levels of the process from pre-treatment to succinic acid production. Chemical-physical pretreatments seemed to be the most appropriate for the pretreatment of lignocellulosic biomass, but many strategies are still needed to solve the problem of variability in initial composition, the presence of post-treatment inhibitory compounds and the use of green solvent. In addition, the saccharization-fermentation process seemed to be the most suitable for the fermentative process of hydrolysates obtained from pretreatment to produce bio-based succinic acid. Certainly new studies and strategies are still needed to overcome the weaknesses of the whole process of succinic acid production from lignocellulosic biomass
Anomaly Detection in Public Street Lighting Data Using Unsupervised Clustering
No full textThe digitization of the energy industry enables the collection and analysis of vast amounts of consumption data for improved decision-making and efficient energy resource utilization. This big data represents an opportunity to address data quality issues and identify anomalies. The detection of anomalies in data that significantly deviates from normal behavior is critical, as they can lead to economic losses. To extract valuable insights and mitigate such challenges, big data analytics platforms and machine learning techniques are increasingly being adopted. Their practical use is crucial in defining consumer-centric, sustainable, and resilient technologies for Industry 5.0. In this article, we address the problem of anomaly detection in electricity consumption for public street lighting. We present our approach and experience in analyzing anomalous behavior of public street lighting plants using electric energy data collected and provided by the ENEA PELL smart city platform. To this end, we adopt three well-known unsupervised clustering techniques: k-means, DBSCAN, and OPTICS. We conduct a comparative analysis of these methods using a real benchmark data set and additional data with known anomalies, used as ground truth data, to verify the correctness of the methods. We synthetically generate additional data from the real data set by automatically injecting anomalies based on specific patterns of anomalous behavior identified for the public street lighting domain. We examine the clustering methods' performance by calculating their accuracy in detecting synthetic anomalies, as well as their computation cost. The experiments show that while K-means runs faster, DBSCAN is more accurate than K-means and OPTICS in detecting synthetic anomalies
Experimental characterization of a novel combined composite reinforced mortar - fibre Bragg grating technology for the retrofit and control of existing structures
No full textThis article investigates the potential of a novel integrated system for the strengthening and monitoring of existing structures. The proposed technology combines Composite Reinforced Mortar (CRM) reinforcements and Fibre Bragg Grating (FBG) sensors and is named as CRM-FBG. Direct tensile tests were conducted as the first step of prototype development and were aimed at evaluating the performance and feasibility of the CRM-FBG system. Measurements provided by FBG sensors were compared to Digital Image Correlation data. The outcomes of the laboratory experiments showed the reliability of the proposed technology, with interesting prospective applications for the retrofit and structural health monitoring of the built heritage
Design of Co-Al-Mn LDH@Ti2CTx Asymmetric Supercapacitor: A Comprehensive Study on the Role of Redox Electrolyte and Its Application in Flexible Electronics
No full textThe unrivaled depth of the energy crisis has imposed a critical challenge to appraise the existing innovations in energy storage devices. Supercapacitors lag behind in terms of energy density, on par with batteries, which has led to the development of hybrid capacitors exhibiting improved energy density. Despite possessing good physiochemical properties proportionate to Ti3C2Tx MXene, Ti2CTx has been less explored. In this study, we exploited the theoretical aspects of Ti2CTx to elucidate its potential as a promising supercapacitor device. Further, to improve the performance and stability of Ti2CTx, we have coupled it with a Co-Al-Mn layered double hydroxide (LDH) via a facile ultrasonication approach. The electrochemical parameters of Co-Al-Mn LDH@Ti2CTx were assessed in a redox additive electrolyte, viz., potassium hydroxide and potassium ferricyanide (6 M KOH + 0.01 M K3[Fe(CN)6]). The addition of Fe(CN)63- ameliorates the performance due to the arousal of the redox couple during the charging and discharging of the supercapacitor device. A redox mechanism has been proposed to highlight the improvement of the performance when a redox additive is used. The Co-Al-Mn LDH@Ti2CTx electrode displays a specific capacitance value of 221 F/g at 5 mVs-1. A solid-state flexible device was constructed with a PVA/KOH gel electrolyte, which exhibited good stability despite twisting the electrode at various bending angles. To elucidate the practicability of the constructed device, a red LED light was illuminated using three electrodes arranged in series