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Visible proton Bragg curve imaging by colour centre photoluminescence in radiation detectors based on lithium fluoride films on silica
Get PDFPassive solid-state radiation detectors, based on the visible photoluminescence (PL) of radiation-induced colour centres in optically transparent lithium fluoride (LiF), polycrystalline thin films are under investigation for proton beam advanced diagnostics. After proton exposure, the latent images stored in LiF as local formations of stable F2 and F3+ aggregate defects, are directly read with a fluorescence microscope under illumination in the blue spectral range. Adopting a suitable irradiation geometry, the energy density that protons deposit in the material can be recorded as a spatial distribution of these light-emitting defects, from which a luminous replica of the proton Bragg curve can be thereafter extracted and analysed to reconstruct the proton beam energy spectrum. Their peculiar properties, such as wide dynamic range and linearity of the spectrally-integrated PL response vs. dose, make the investigation of two-dimensional LiF film radiation detectors grown on several types of substrate highly attractive. Here, the case of a LiF thin film thermally evaporated on a silica substrate, irradiated at grazing incidence with a 35 MeV proton beam, is investigated and reported for the first time. A comparison of the measured photoluminescent Bragg curve with Monte Carlo simulations demonstrates that the Bragg peak in the film is located at the very same position that would be expected in the underlying silica substrate rather than in LiF. The film packing density is shown not to have a significant effect on the peak depth, while even small nonzero grazing angle of the impinging proton beam is able to significantly modify the shape of the Bragg curve. These findings are ascribed to the effects of multiple Coulomb scattering in both the film and the substrate and are interesting for proton beam diagnostics and dosimetry
Validation activities at ENEA Brasimone in support of the IFMIF-DONES design
Get PDFIFMIF-DONES is a powerful neutron source which is being designed with the main purpose of qualifying structural materials (EUROFER being the first candidate) to be used in DEMO and fusion power plants envisaged after it. This source relies on one high current (125 mA) deuterons beam accelerated to 40 MeV which impacts on a liquid lithium target to produce an intense neutron flux through Li(d,n) stripping reactions able to simulate the nuclear responses expected on the first wall of the reactor. The engineering design of IFMIF-DONES is presently being carried out mainly in the framework of the EUROfusion Work Package Early Neutron Source (WPENS). Since 2021, a new phase has started with the launch of the FP9 WPENS workplan whose objective is to continue advancing the engineering design of the facility, putting special effort on the experimental validation of those aspects which still need to be qualified to demonstrate the fulfillment of functional and safety requirements. The ENEA Brasimone Research Centre has been and still is strongly committed in several validation tasks concerned in particular with the lithium systems design and the Remote Handling (RH) maintenance. In this paper, an overview of the most relevant validation activities carried out in recent years or still in progress or planned at the ENEA Brasimone Research Centre in both of the aforementioned areas is presented, including the erosion/corrosion tests in the Lifus 6 loop; the nitrogen-gettering materials qualification in the ANGEL facility; and the RH and prototypes testing in the DRP laboratory for the validation of the High Flux Test Module electric connectors and the pre-heating of the Target Assembly
Optimization of DC Energy Storage in Tokamak Poloidal Coils
Get PDFTokamaks are a very promising option to exploit nuclear fusion as a programmable and safe energy source. A very critical issue for the practical use of tokamaks consists of the power flow required to initiate and sustain the fusion process, in particular in the poloidal field coils. This flow can be managed by introducing a DC energy storage based on supercapacitors. Because such storage may be the most expensive and largest part of the poloidal power supply system, an excessive size would cancel its potential advantages. This paper presents innovative strategies to optimize the DC storage in poloidal power supply systems. The proposed solution involves the sharing of the DC storage between different coil circuits. The study is supported by novel analytical formulas and by a circuital model developed for this application. The obtained results show that this method and the related algorithms can noticeably reduce the overall size of the storage and the power exchange with the grid, providing a practical contribution toward the feasibility and the effectiveness of nuclear fusion systems
MADE Macro-Block III: Transitioning From the Optimized TF Coil Shape to the PF Coil System
No full textThe MAgnet Design Explorer (MADE) is a Tokamak design algorithm developed initially for the DTT CS, and largely extended within the EUROfusion DEMO project [1]. MADE could function as a valuable tool for navigating the initial design stage of a tokamak project. In response to the technological developments in recent years, it has been deemed necessary to define a means capable of estimating how machine size and performance change in response to the target parameters imposed by plasma physics and by the performance of the superconducting magnet system. The MADE algorithm previously included two sequenced macro-blocks, the first dedicated to defining the toroidal magnetic field system, and the second to define the central solenoid of the machine. These macro-blocks generate two of the three main magnetic systems of the Tokamak. This paper describes the studies completed to define and implement the third macro-block, which models the poloidal coil system and the plasma vertical stability. The resulting suite of algorithms are now combined to reach an optimized winding pack architecture for all major tokamak coils at a given plant operating point. A case study based on ITER is presented in this work
A novel tomato interspecific (Solanum lycopersicum var. cerasiforme and Solanum pimpinellifolium) MAGIC population facilitates trait association and candidate gene discovery in untapped exotic germplasm
Get PDFWe developed a novel eight-way tomato multiparental advanced generation intercross (MAGIC) population to improve the accessibility of tomato relatives genetic resources to geneticists and breeders. The interspecific tomato MAGIC population (ToMAGIC) was obtained by intercrossing four accessions each of Solanum lycopersicum var. cerasiforme and Solanum pimpinellifolium, which are the weedy relative and the ancestor of cultivated tomato, respectively. The eight exotic ToMAGIC founders were selected based on a representation of the genetic diversity and geographical distribution of the two taxa. The resulting MAGIC population comprises 354 lines, which were genotyped using a new 12k tomato single primer enrichment technology panel and yielded 6488 high-quality single-nucleotide polymorphism (SNPs). The genotyping data revealed a high degree of homozygosity, an absence of genetic structure, and a balanced representation of the founder genomes. To evaluate the potential of the ToMAGIC population, a proof of concept was conducted by phenotyping it for fruit size, plant pigmentation, leaf morphology, and earliness. Genome-wide association studies identified strong associations for the studied traits, pinpointing both previously identified and novel candidate genes near or within the linkage disequilibrium blocks. Domesticated alleles for fruit size were recessive and were found, at low frequencies, in wild/ancestral populations. Our findings demonstrate that the newly developed ToMAGIC population is a valuable resource for genetic research in tomato, offering significant potential for identifying new genes that govern key traits in tomato. ToMAGIC lines displaying a pyramiding of traits of interest could have direct applicability for integration into breeding pipelines providing untapped variation for tomato breeding
TetraBall: A single-moderator neutron spectrometer for HL-LHC
Get PDFThis contribution presents a novel single-moderator neutron spectrometer, named “TetraBall”, developed at INFN and optimized for characterizing the neutron field in the CMS experimental cavern. The TetraBall condenses the functionality of several Bonner Spheres (BS) in a single moderator and it is equipped with 42 SiC radiation-hard detectors organized in a tetrahedral geometry designed to be insensitive to incident gammas and charged particles. Thanks to lead inserts, it can respond up to GeV energies. It works in single exposure mode, suitable for real-time monitoring. It is designed to be used as neutron monitor during the High-Luminosity LHC data taking
Wearable Sensor Node for Safety Improvement in Workplaces: Technology Assessment in a Simulated Environment
Get PDFPersonal protective equipment (PPE) has been universally recognized for its role in protecting workers from injuries and illnesses. Smart PPE integrates Internet of Things (IoT) technologies to enable continuous monitoring of workers and their surrounding environment, preventing undesirable events, facilitating rapid emergency response, and informing rescuers of potential hazards. This work presents a smart PPE system with a sensor node architecture designed to monitor workers and their surroundings. The sensor node is equipped with various sensors and communication capabilities, enabling the monitoring of specific gases (VOC, CO2, CO, O2), particulate matter (PM), temperature, humidity, positional information, audio signals, and body gestures. The system utilizes artificial intelligence algorithms to recognize patterns in worker activity that could lead to risky situations. Gas tests were conducted in a special chamber, positioning capabilities were tested indoors and outdoors, and the remaining sensors were tested in a simulated laboratory environment. This paper presents the sensor node architecture and the results of tests on target risky scenarios. The sensor node performed well in all situations, correctly signaling all cases that could lead to risky situations
Influence of a Solid Surface on PNIPAM Microgel Films
Get PDFStimuli-responsive microgels have attracted great interest in recent years as building blocks for fabricating smart surfaces with many technological applications. In particular, PNIPAM microgels are promising candidates for creating thermo-responsive scaffolds to control cell growth and detachment via temperature stimuli. In this framework, understanding the influence of the solid substrate is critical for tailoring microgel coatings to specific applications. The surface modification of the substrate is a winning strategy used to manage microgel–substrate interactions. To control the spreading of microgel particles on a solid surface, glass substrates are coated with a PEI or an APTES layer to improve surface hydrophobicity and add positive charges on the interface. A systematic investigation of PNIPAM microgels spin-coated through a double-step deposition protocol on pristine glass and on functionalised glasses was performed by combining wettability measurements and Atomic Force Microscopy. The greater flattening of microgel particles on less hydrophilic substrates can be explained as a consequence of the reduced shielding of the water–substrate interactions that favors electrostatic interactions between microgels and the substrate. This approach allows the yielding of effective control on microgel coatings that will help to unlock new possibilities for their application in biomedical devices, sensors, or responsive surfaces
Sustainability analysis of organic waste management in the Metropolitan Area of Barcelona
Get PDFNell’ambito del progetto Biocircularcities (BCC), è stata analizzata la sostenibilità ambientale ed economica della gestione dei rifiuti organici urbani dell'Area Metropolitana di Barcellona (MAB, Spagna), mediante le metodologie Valutazione del Ciclo di Vita (LCA) e Costo del Ciclo di Vita (LCC). Lo scenario attuale (Business-as-Usual, BaU) prevede la raccolta differenziata volontaria in contenitori aperti, il trasporto giornaliero e il trattamento in un impianto locale (ECOPARC 2) per produrre compost e biogas; quest’ultimo viene poi convertito in elettricità in un impianto di cogenerazione. Lo scenario BaU è stato confrontato con un'alternativa che ipotizza misure di prevenzione della produzione di rifiuti, la separazione dei rifiuti organici obbligatoria tramite raccolta porta a porta o contenitori intelligenti, un trasporto meno frequente e l'upgrading del biogas a biometano da immettere nella rete nazionale del gas naturale. L'analisi LCA ha identificato, come principali responsabili degli impatti ambientali, il trasporto, la produzione di elettricità e la digestione anaerobica (per la generazione di biogas). I benefici ambientali, invece, derivano dall'evitato uso di gas naturale e fertilizzanti chimici. Inoltre, le analisi LCC hanno evidenziato che, rispetto allo scenario BaU, quello alternativo presenta costi interni leggermente inferiori e un costo totale del danno ambientale quasi dimezzato. Tuttavia, a causa della limitata disponibilità di dati primari, sono stati utilizzati valori medi europei, sicché i risultati LCA e LCC sono da considerarsi meramente indicativi.The environmental and economic sustainability of the urban organic waste management in the Metropolitan Area of Barcelona, Spain, was analyzed in the Biocircularcities (BCC) project, through Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methodologies. The current (Business-as-Usual, BaU) scenario involves voluntary separate collection in open containers, daily transport and processing at a local facility (ECOPARC 2) to produce compost and biogas with the latter being converted into electricity at a Combined Heat and Power (CHP) plant. The BaU scenario was compared with an alternative scenario that envisages biowaste prevention measures, mandatory separate collection through door-to-door or smart bins, less frequent transport and upgrading biogas to biomethane for injection into the natural gas national grid. LCA identified transport, electricity production and anaerobic digestion (for biogas generation) as the primary contributors to environmental burdens. On the other hand, environmental gains arise from the avoided use of natural gas and chemical fertilizers. Moreover, LCC analyses highlighted that the alternative scenario, compared to the BaU scenario, has slightly lower internal costs and almost half the total environmental damage cost. However, due to limited primary data, European averages were used, so the LCA and LCC findings should be considered as merely indicative
Skewness and kurtosis of mean transverse momentum fluctuations at the LHC energies
No full textThe first measurements of skewness and kurtosis of mean transverse momentum (〈pT〉) fluctuations are reported in Pb–Pb collisions at sNN = 5.02 TeV, Xe–Xe collisions at sNN = 5.44 TeV and pp collisions at s=5.02 TeV using the ALICE detector. The measurements are carried out as a function of system size 〈dNch/dη〉|η|<0.51/3, using charged particles with transverse momentum (pT) and pseudorapidity (η), in the range 0.2<3.0 GeV/c and |η|<0.8, respectively. In Pb–Pb and Xe–Xe collisions, positive skewness is observed in the fluctuations of 〈pT〉 for all centralities, which is significantly larger than what would be expected in the scenario of independent particle emission. This positive skewness is considered a crucial consequence of the hydrodynamic evolution of the hot and dense nuclear matter created in heavy-ion collisions. Furthermore, similar observations of positive skewness for minimum bias pp collisions are also reported here. Kurtosis of 〈pT〉 fluctuations is found to be in good agreement with the kurtosis of Gaussian distribution, for most central Pb–Pb collisions. Hydrodynamic model calculations with MUSIC using Monte Carlo Glauber initial conditions are able to explain the measurements of both skewness and kurtosis qualitatively from semicentral to central collisions in Pb–Pb system. Color reconnection mechanism in PYTHIA8 model seems to play a pivotal role in capturing the qualitative behavior of the same measurements in pp collisions