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Polymer electrolytes based on protic ionic liquids with perfluorinated anions for safe lithium-ion batteries
No full textThe quest for safe and high-performance polymer electrolytes in lithium-ion batteries (LIBs) has led researchers to explore protic ionic liquids (PILs) as potential candidates to be entrapped in polymer matrices. In this context, we present an investigation into solid polymeric systems based on poly(methyl methacrylate) (PMMA) as a host for PILs, featuring 1,8-diazabicyclo-[5,4,0]-undec-7-ene (DBU) cation paired with three different anions: bis(trifluoromethanesulfonyl)imide (TFSI−), trifluoromethanesulfonate (TFO−), and (trifluoromethanesulfonyl-nonafluorobutylsulfonyl)imide (IM14−). Additionally, we explore the lithium-doped IM14-gel-like system to broaden our understanding of these intriguing materials. Through comprehensive thermal analysis, solid-state NMR, and diffusion NMR techniques, we delve into the interactions and structural features of these binary and ternary polymeric systems. Our investigation reveals unique dynamics and ion interactions within the PMMA matrix, shedding light on the potential of these materials for advanced energy storage technologies. Particularly, we highlight the distinctive features of DBUH-IM14 and its specific interaction with the polymeric matrix and the lithium ions, underscoring its significance in advancing safer and more efficient energy storage devices
First-principle based predictions of the effects of negative triangularity on DTT scenarios
Get PDFPlasmas with negative triangularity (NT) shape have been recently shown to be able to achieve H-mode levels of confinement in L-mode, avoiding detrimental edge localised modes. Therefore, this plasma geometry is now studied as a possible viable option for a future fusion reactor. Within this framework, an NT option is under investigation for the full power scenario of the Divertor Tokamak Test (DTT) facility, under construction in Italy, with δ t o p = − 0.32 / δ b o t t o m ≃ 0.02 top/bottom triangularity values at the separatrix. The transport properties of this scenario are studied in this work. Gyrokinetic GENE simulations and integrated modelling using ASTRA with the quasi-linear trapped gyro-Landau fluid (TGLF) model have been performed. The emerging picture from the ASTRA-TGLF runs with boundary conditions at ρ t o r = 0.94 is that, in the L-mode NT option, the larger peaking of the kinetic profiles in the edge region is not sufficient to recover the loss of the PT H-mode pedestal, and reach similar central temperature values. Two additional shapes are also considered, obtained by flipping the triangularity of the scenarios, to single out the effect of the triangularity sign. A negligible ‘direct’ effect of the triangularity is found for the L-mode, while a small beneficial effect is observed for the H-mode. The ASTRA-TGLF results are validated by GENE and TGLF stand-alone at two selected radii. GENE shows ITG dominant micro-instability and explains the small beneficial effect of the NT for the H-mode as due to a strong reduction of the heat fluxes, when reversing the triangularity, with a relatively high T i stiffness. An improvement of the predicted performances of the NT DTT scenario could come from ρ tor ≳ 0.9 , as indicated by some recent experiments at the tokamak à configuration variable (TCV) and ASDEX Upgrade
Supercapacitor Characterization Over a Wide Current Range
No full textSupercapacitors offer distinct advantages over traditional batteries or other energy storage systems, such as high-power density and extended lifecycle. However, it is crucial to accurately model their behavior under various operating conditions, especially at high currents exceeding hundreds of amperes. This study explores the effectiveness of an equivalent model, previously introduced in the literature, but extends its testing range from 20 A up to the nominal current of the devices (140 A) in continuous mode. The tests are performed on large commercial supercapacitor cells contributing to a deeper understanding of supercapacitor performance in real-world scenarios
Syngas-driven sewage sludge conversion to microbial protein through H2S- and CO-tolerant hydrogen-oxidizing bacteria
No full textTreating excess municipal sewage sludge (MSS) by means of thermochemical processes could enable its conversion into high-value microbial protein (MP) through syngas. Nevertheless, the variable composition and content of inhibitory compounds of the latter hinders the application potential of such a biorefinery scheme. Through a series of short- (48 to 96 h) and long-term (30 days) batch aerobic bioconversion tests, the present study aimed at investigating the potential of a mixed culture of hydrogen-oxidizing bacteria (HOB) to produce MP from a simulated syngas mixture characterized by variable H2 and CO2 concentrations, and different levels of CO and H2S as potential inhibitors of the HOB-driven process. Syngas was converted into MP with a protein content as high as 74 %, reaching biomass yields of 0.25 g VSS/g H2-COD, close to the maximum reported HOB yield of 0.28 g VSS/g H2-COD, and volumetric productivities of 16 mg VSS/L/h. The potential of the process to provide between 50 and 100 % of the total nitrogen requirement of HOB solely by means of the gaseous ammonia nitrogen recovered through syngas was also preliminarily calculated. The presence of H2S and CO concentrations up to 0.4 % and up to 40 %, respectively, and a wide range of H2/CO2 ratios (2 – 10) had no negative influence on the main process performances. The role played by H2S- and CO-tolerant HOB species was fundamental to guarantee a high tolerance to microbial inhibitors, and demonstrated the high potential of mixed cultures for resource recovery and valorisation
Structural and electronic characterization of Pb adsorption on clean and Cr or Ni doped Fe(1 0 0) surface: An ab-initio study
Get PDFUsing ab-initio calculations, the interaction of lead adatom on both the clean and doped iron (100) surfaces has been investigated. The adsorption energies show that the hollow site provides a more stable configuration with respect to the top and bridge sites, and, in this position, the lead adatom is more energetically favourable than the iron adatom. On the other hand, lead adsorbed in the hollow site of the iron (100) surface doped with chromium, provides more stable system than the nickel doped surfaces with an iron atom adsorbed in the same position. Detailed investigations of inter-layer distances, bonding mechanisms in terms of the projected density of states, magnetic behaviours, and charge density differences are also presented. Our results give insights in the role of the doping the interaction between lead adatom and iron surface, and then, this study may be exploited in the analysis of the corrosion process due to liquid lead
Multiscale Thermal-Hydraulic Analysis of the ATHENA Core Simulator
No full textIn the framework of the ALFRED research and development program, the ATHENA facility will be constructed for thermal-hydraulic analysis of full-scale ALFRED components and systems. The source system of the facility is the core simulator, which aims to be representative of an ALFRED average fuel assembly. Computational fluid dynamics (CFD) codes are gaining attention for the analysis of complex systems in pool-type reactors since they are able to reproduce three-dimensional phenomena. In this paper, a multiscale approach based on porous media is proposed to reduce the computational cost of the core simulator CFD model. The multiscale approach starts with the detailed simulation of the infinite lattice domain of the fuel assembly to characterize the porous media hydraulic behavior. Then the porous media are applied in the system model. Three different approaches are investigated: (1) adopting a single porous media for the entire fuel assembly, (2) representing the bundle with two porous domains, and (3) adopting the so-called hybrid medium. The results have been compared with the reference detailed CFD simulation for performance evaluation. The first step of the analysis is the application of the multiscale approach on the CIRCE fuel pin simulator to carry out a turbulence model validation against experimental data and a comparison of the three approaches with a proven CFD model. Then the approach is applied on the ATHENA core simulator exploiting the CIRCE results. The results obtained with the porous media models are compared with a detailed CFD simulation of the core simulator to evaluate the performance of the three approaches. Eventually, the best solution is applied on a model of the entire ATHENA core simulator integrated with the feeding region. The model is tested also in transient conditions. The numerical experiment demonstrates the effectiveness of the multiscale approach in reducing the computational cost while maintaining high accuracy in representing the quantities of interest
Differential Gene Expression in Late-Onset Friedreich Ataxia: A Comparative Transcriptomic Analysis Between Symptomatic and Asymptomatic Sisters
Get PDFFriedreich ataxia (FRDA) is the most common inherited ataxia, primarily impacting the nervous system and the heart. It is characterized by GAA repeat expansion in the FXN gene, leading to reduced mitochondrial frataxin levels. Previously, we described a family displaying two expanded GAA alleles, not only in the proband affected by late-onset FRDA but also in the younger asymptomatic sister. The molecular characterization of the expanded repeats showed that the affected sister carried two canonical uninterrupted GAA expended repeats, whereas the asymptomatic sister had a compound heterozygous for a canonical GAA repeat and an expanded GAAGGA motif. Therefore, we decided to perform RNA sequencing (RNA-seq) on fibroblasts from both sisters in order to understand whether some genes and/or pathways might be differently involved in the occurrence of FRDA clinical manifestation. The transcriptomic analysis revealed 398 differentially expressed genes. Notably, TLR4, IL20RB, and SLITRK5 were up-regulated, while TCF21 and GRIN2A were down-regulated, as validated by qRT-PCR. Gene ontology (GO) enrichment and network analysis highlighted significant involvement in immune response and neuronal functions. Our results, in particular, suggest that TLR4 may contribute to inflammation in FRDA, while IL20RB, SLITRK5, TCF21, and GRIN2A dysregulation may play roles in the disease pathogenesis. This study introduces new perspectives on the inflammatory and developmental aspects in FRDA, offering potential targets for therapeutic intervention
Semitransparent Perovskite Solar Submodule for 4T Tandem Devices: Industrial Engineering Route Toward Stable Devices
Get PDFPerovskite technology has been advancing at unprecedented levels over the past years, with efficiencies reaching up to 26.1%. State-of-The-Art results are obtained on a very small area scale (<0.1 cm2), by adopting high materials wasting processes not compatible with industry and with market exploitation. Silicon is a well-established technology and one of the advantages of perovskite is its ability to pair with silicon forming a tandem device that extracts charges reducing transmission and thermalization losses. In this work, we focused on finding a strategy to fabricate 15.2 × 15.2 cm2 perovskite modules by using blade/slot-die coating and avoiding any spin coating deposition. Furthermore, we optimized the indium tin oxide top electrode deposition by adjusting the sputtering process and buffer layer deposition; finally, we focused on light management by applying an antireflective coating. We obtained a semitransparent and a tandem silicon-perovskite module in a four-Terminal (4T) configuration over 225 cm2 (4T configuration) with 13.18% and 20.91% efficiency, respectively, passing International Summit on Organic PV Stability ISOS-L1 (under continuous light soaking in the air) test with a remarkable T80 of 1459 h
Blockchain and industrial symbiosis: a preliminary two-step framework to green circular supply chains
Get PDFThe strategic management of supply chains, by ensuring closed-loop manufacturing processes and a constant reduction of industrial waste, is an essential pillar of sustainability. This is the pattern behind the, so-called, circular supply chains. The effective adoption of this paradigm demands the supply chains actors to establish robust integration and relationships, so that waste and by‐products of an industry or industrial process become the raw materials for others. This circular network is defined as industrial symbiosis. Starting from a background on this topic, this working paper explores the potential of blockchain as enabling technology of Industry 4.0 to disseminate industrial symbiosis practices within the modern industrial scenario. A preliminary two-step framework, i.e., conceptual and operative, is presented including insights and win–win synergies showing the potential of blockchain technology in supporting informative flows of industrial symbiosis. Preliminary field experiences are suggested, along with existing limitations and perspectives on future research
Quantum isotropic Universe in RQM analogy: The cosmological horizon
No full textWe investigate the quantum dynamics of the isotropic Universe in the presence of a free massless scalar field, playing the role of a physical clock. The Hilbert space is constructed via a direct analogy between the Wheeler-DeWitt equation in the minisuperspace and a relativistic scalar one in physical space. In particular, we show how the introduction of a “turning point” in the Universe evolution allows to overcome an intrinsic ambiguity in representing the expanding and collapsing Universe. In this way, the positive and negative frequencies are simply identified with time reversed states. The main subject of the present analysis is the construction of a horizon operator, whose quantum behavior is investigated when Polymer Quantum Mechanics is implemented to describe the asymptotic evolution near the initial singularity. The reason of this choice is motivated by the intrinsic spreading of localized wavepackets when the polymer dispersion relation governs the quantum dynamics. The evidence that the mean value of the quantum horizon operator follows its semiclassical behavior (corrected for polymerization) is a clear indication that a concept of causality can be restored also in the quantum cosmological picture