High Current Energy Research Articles

A unified machine learning approach for reconstructing hadronically decaying tau leptons

Tau leptons serve as an important tool for studying the production of Higgs and electroweak bosons, both within and beyond the Standard Model of particle physics. Accurate reconstruction and identification of hadronically decaying tau leptons is a crucial task for current and future high energy physics experiments. Given the advances in jet tagging, we demonstrate how tau lepton reconstruction can be decomposed into tau identification, kinematic reconstruction, and decay mode classification in a multi-task machine learning setup. Based on an electron-positron collision dataset with full detector simulation and reconstruction, we show that common jet tagging architectures can be effectively used for these sub-tasks. We achieve comparable momentum resolutions of 2–3% with all the tested models, while the precision of reconstructing individual decay modes is between 80–95%. We find ParticleTransformer to be the best-performing approach, significantly outperforming the heuristic baseline. This paper also serves as an introduction to a new publicly available Fuτure dataset for the development of tau reconstruction algorithms. This allows to further study the resilience of ML models to domain shifts and the efficient use of foundation models for such tasks.

Recent Progress in Cobalt‐Based Electrocatalysts for Efficient Electrochemical Nitrate Reduction Reaction

AbstractElectrochemical nitrate reduction reaction (NO3−RR) provides a sustainable and efficient way to producing ammonia at ambient condition and denitrifying wastewater. However, NO3−RR is still confronted with some barriers at present, because of the sluggish reaction kinetics and competitive hydrogen evolution reaction (HER). Particularly, it requires highly robust and selective electrocatalysts, which steers the complex multistep reactions toward NO3−RR process. Among the various electrocatalysts, Co‐based electrocatalysts demonstrate a rapid reaction kinetics, steady catalytic performance, and suppressive impact on HER for NO3−RR, attracting more attention. In this review, it is focused on Cobalt‐based electrocatalysts design for NO3−RR and the corresponding design strategies are summarized. In detail, these can be concisely classified into five categories, including the Co‐based oxides and hydroxides, alloys, metal, and heteroatom‐doped materials, metal organic frameworks and derivatives. Each category is extensively discussed, with its design concepts and ideas clearly conveyed through appropriate illustrations and figures. Finally, the scientific and technological challenges as well as promising constructing strategies for NO3−RR system in the future are discussed. It is expected that this review can provide valuable insights and guidance into rational design of Co‐based electrocatalysts for NO3−RR, ultimately advancing their applications to industrial scenario with high current density, stability, and energy efficiency.

Constructing valid Li+ fast-transfer channels on novel P(TPC@Lys-Li) separator to enable security, high energy density, and controllable Li dendrites for lithium-metal batteries

Lithium metal batteries (LMBs) attract widespread attention under current high energy density developments. However, wild Li dendrite propagations owing to chaotic Li depositions raise challenges for LMB blossoming. Separators with specific demands thus should be involved when smoothly transferring into LMBs. In this research, a fascinating P(TPC@Lys-Li) separator is prepared by the turbulent interfacial polymerization and electrospinning to ingeniously clarify dependencies of Li+ transfer dynamics on double electric layer thickness (DELT) regulations within porous skeletons. P(TPC@Lys-Li) enables negatively charged porous skeleton surface and compresses DELT, which constructs high-efficiency Li+ fast-transfer channels on porous skeletons and accelerates Li+ transfer speed by 18.3 times. Especially, P(TPC@Lys-Li) supplies extra Li+ for stable formations of solid electrolyte interphase (SEI) layer, homogenizing nucleation and growth behaviors during Li depositions. Remarkable C-rate capacity and cycle stability thus arise for assembled LMBs, holding 87.2 % capacity retention after 700 cycles at 0.5C even under high cathode loading and lean electrolyte conditions. P(TPC@Lys-Li) also maintains constant physical scale and unabated mechanical strength even at elevated temperatures approaching 200 °C, which provides excellent battery security as LMBs encounter uncontrollable thermal runaway. Above attractive features enable P(TPC@Lys-Li) separator to be potentially applied in LMBs demanding sufficient security, high-capacity density, and fast charge technology.

Sulfonated poly(aryl ether) proton exchange membrane with excellent dimensional stability for hydrogen production by water electrolysis

The use of proton exchange membrane water electrolysis (PEMWE) for hydrogen production is considered a promising technology due to its high theoretical current density, gas purity, and energy efficiency. In this study, a fluorinated sulfonated hydrocarbon polymer was used to prepare hydrocarbon−based membranes for PEMWE that displayed exceptional stability. Notably, the SFPAE-60 membrane has a proton conductivity of up to 293.1 mS cm−2 at 80 °C and 100%RH, but its volumetric swelling ratio is only 47 %. Its dimensional stability is significantly better than that of previously reported sulfonated poly (aryl ether)−based proton exchange membranes (>100 %). The PEMWE based on the SFPAE-60 membrane achieves a current density of over 4800 mA cm−2 at 2.0V, confirming the membrane's applicability in actual water electrolysis. The results indicate that the electrolyte membrane of fluorinated sulfonated hydrocarbon polymer performs well in the PEM electrolyzer.

Investigation of hydrohalic acids as lixiviants for the leaching of cathode metals from spent lithium-ion batteries

The exploration of alternative energy sources is inextricably linked with energy storage considerations. Current high density energy storage options on the market rely heavily on lithium (Li)-based technologies. A projected increase in energy storage technology demand has sounded the alarm on a need to develop suitable approaches for the recovery of the various constituent metals from spent Li-ion batteries (LIBs). This, coupled with urgent consideration for the environment has necessitated the investigation of various LIB metal recovery techniques. In this work, we explore the novel application of the hydrohalic acids, hydrobromic (HBr) and hydroiodic (HI) acid, as lixiviants in a series of leaching experimental investigations on LIB cathode powder. A methodology for battery disassembly and cell cathode material recovery is presented leading up to the metal leaching. Our results indicate that the lixiviants can be utilized in the absence of a reducing agent which is typically present in conventional LIB leaching systems. The highest recoveries of the constituent metals, Co, Li, Mn and Ni in the HI system were 92.9 %, 93.6 %, 93.1 % and 94.5 % respectively, at an operating temperature of 60 ℃ and with a 1.5 M HI concentration. The HBr system achieved metal recoveries of 90.6 %, 89.1 %, 83.1 % and 96.4 % for Co, Li, Mn and Ni respectively, at 60 ℃ and using 2 M HBr. Kinetic studies showed that the leaching mechanism for both acids follow a chemical reaction-controlled model.

Optimize the event selection strategy to study the anomalous quartic gauge couplings at muon colliders using the support vector machine and quantum support vector machine

The search of the new physics (NP) beyond the Standard Model is one of the most important topics in current high energy physics. With the increasing luminosities at the colliders, the search for NP signals requires the analysis of more and more data, and the efficiency in data processing becomes particularly important. As a machine learning algorithm, support vector machine (SVM) is expected to to be useful in the search of NP. Meanwhile, the quantum computing has the potential to offer huge advantages when dealing with large amounts of data, which suggests that quantum SVM (QSVM) is a potential tool in future phenomenological studies of the NP. How to use SVM and QSVM to optimize event selection strategies to search for NP signals are studied in this paper. Taking the tri-photon process at a muon collider as an example, it can be shown that the event selection strategies optimized by the SVM and QSVM are effective in the search of the dimension-8 operators contributing to the anomalous quartic gauge couplings.

Effects of family non-universal Z ′ model in angular observables of decays* *Supported by the Higher Education Commission of Pakistan through (NRPU/20-15142)

We present the angular distribution of the four-fold and decays in the Standard Model and family non-universal model. At the quark level, these decays are governed by the transition. Along with different angular observables, we provide predictions of differential branching ratios, forward-backward asymmetry, and longitudinal polarization fractions of and mesons. Our analysis shows that the signatures of the family non-universal model are more distinct in the observables associated with the decay than in those associated with the decay. Future measurements of the predicted angular observables, both at current and future high energy colliders, will provide useful complementary data required to clarify the structure of the family non-universal model in = processes.

Palladium nanocubes-mediated Fenton catalysis combined with chloride ion-amplified electro-driven catalysis for dye degradation

Electrochemical technology is frequently used to treat industrial dye wastewater. However, its degradation efficiency is restricted by pH, and the low current efficiency and high energy consumption limit its broader application. Based on this, we constructed an innovative electro-driven catalytic system by integrating nanotechnology with electric current. This system operates without pH constraints, has low energy consumption, and allows for the recycle and reuse of both electrodes and catalysts. Firstly, we synthesized palladium (Pd) cubes via a solvothermal method, and characterized their morphology, structural composition, and crystalline properties using transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and other methods. The prepared Pd cubes possessed dual catalytic properties of electro-driven catalysis and Fenton catalysis, achieving a synergistic degradation effect under an electric field. Subsequently, the study explored how catalysts dosage, H2O2 concentration, pH and Cl− concentration affect the catalytic rate. The optimized system was able to degrade 99.17 % of MB within 1 h and was effective against various organic pollutants. After five cycles of reuse, the recovered catalysts maintained over 90 % degradation efficiency in decomposing MB. This process realizes efficient degradation with a low concentration of catalysts, offering a novel approach for nanotechnology in wastewater treatment under electro-driven conditions.

Utilizing CO2 as a strategy to scale up direct air capture may face fewer short-term barriers than directly storing CO2

Direct air capture (DAC) is increasingly recognized as a necessary puzzle piece to achieve the Paris climate targets. However, the current high cost and energy intensity of DAC act as a barrier. Short-term strategies for initial deployment, technology improvement, and cost reduction are needed to enable large-scale deployment. We assess and compare two near-term pathways leading to the same installed DAC capacity and thus yielding the same cost reductions: its combination with CO2 storage as direct air carbon capture and storage, or its deployment for CO2 utilization as direct air carbon capture and utilization e.g. for synthetic fuels, chemicals, and materials; we characterize these as Direct and Spillover pathways. Drawing on the Multi-level Perspective on Technological Transition as a heuristic, we examine both technical and immaterial factors needed to scale up DAC under the two pathways, in order to assess the pathways’ relative advantages and to identify possible short-term bottlenecks. We find neither pathway to be clearly better: the Direct pathway offers technical advantages but faces regulatory barriers that need to be resolved before deployment, while the Spillover pathway offers market and governance advantages but faces challenges related to hydrogen production and increasing resource needs as it scales up. There may be reasons for policymakers to therefore pursue both approaches in a dynamic manner. This could involve prioritizing the Spillover pathway in the short term due to possibly fewer short-term regulatory barriers and its ability to produce net-zero emission products for existing and accessible markets. Once short-term governance obstacles have been addressed, however, the Direct pathway may allow for more efficient scaling of DAC capacity and cost reductions, especially if by then the needed infrastructure and institutions are in place.

Optimising building envelope and insulation materials for energy efficiency and life-cycle cost in Cypriot residences

ABSTRACT Residential buildings consume approximately 36% of total electricity consumption in Cyprus and this is expected to continue increasing in the coming years. This study explores the potential for energy savings in residential buildings in Cyprus through optimising building envelopes and insulation materials. Using building information modelling and energy modelling software, the study analyses 120 combinations of building envelopes and eight insulation materials, identifying an optimal combination of wall, roof, and flooring materials that could result in 32% energy load reductions and 27% lower life-cycle costs compared to the median scenario. High-density rock wool insulation on roofs and double-glazed windows were also found to offer both monetary and energy performance benefits. A sensitivity analysis revealed that the current high energy prices could provide greater economic incentives to adopt these optimisation strategies. Optimising building materials in Cyprus could play a critical role in climate strategy while also offering significant economic benefits.

Using k-means assistant event selection strategy to study anomalous quartic gauge couplings at muon colliders

The search for new physics beyond the Standard Model is one of the central problems of current high energy physics interest. As the luminosities of current and near-future colliders continue to increase, the search for new physics has increased the requirements for processing large amounts of data. Meanwhile, quantum computing which is rapidly evolving, has great potential to become a powerful tool to help search for new physics signals. Since the k-means algorithm is known to be able to be accelerated with the help of quantum computing, we investigate and propose an event selection strategy based on k-means algorithm to search for new physics signals. Taking the case of tri-photon processes at the muon colliders as an example, the event selection strategy is shown to be effective in helping to search for the signals of dimension-8 operators contributing to anomalous quartic gauge couplings. Compared with traditional event selection strategy, the expected constraints are generally tighter.

Electroosmotic reinforcement mechanism and laboratory tests of pulsating direct current with a high energy efficiency ratio

Based on the electroosmotic reinforcement mechanism of pulsating direct current (PDC) with a high energy efficiency ratio, the calculation method of PDC electroosmosis drainage rate was verified under different potential gradients using two forms of voltage loading, i.e., constant direct current (CDC) and PDC. The drainage weight and electric current were achieved by laboratory tests, and then the energy efficiency ratio, soil resistivity and contact resistance was calculated. The energy consumption of each test group was analyzed by considering the initial potential gradient. The obtained results show that under the same potential gradient, the difference in soil resistivity and electroosmotic drainage between PDC and CDC is not significant, but there is a significant difference in contact resistance, which leads to low current intensity and high energy efficiency ratio in the PDC test group. The expression of the electroosmotic drainage rate of the PDC is described with the coefficient μ, and then the energy efficiency ratio versus potential gradient curve is calculated, which is in good agreement with the experimental results. The reason for the lower energy consumption of PDC electroosmosis compared to CDC is described in terms of the drainage mechanism of electroosmosis.

A very low energy ion beam extraction system design of the GTS ECR ion source at GANIL

The GTS ion source, operated at 14.5GHz, provides multiply charged heavy ion beams for the ARIBE facility at GANIL. The facility variety is limited by the efficiency of the extraction especially in the few keV/q domain. In order to improve the ion source, the extraction system was upgraded numerically using IBSimu. The shape of the plasma and the puller electrodes was changed. It causes the increase of the electric field near the plasma meniscus and allows the use of lower extraction voltages at constant total ion beam current. The required beam parameters were taken from the experimental data. The opportunity of effective low energy beam formation (at a few keV/q or several hundreds eV/q beam energy) was studied. The high current and low energy ion beam production will provide new possibilities for ARIBE facility users.

Preliminary design of the FCC-ee vacuum chamber absorbers

In the FCC-ee study, it is proposed that electron and positron beams circulate at high current and high energy in a 92-km circumference twin ring. The present operational scenario foresees a first running step at an energy of 45.6 GeV and around 1.4 A current, which would generate copious amounts of synchrotron radiation (SR) power and flux. To guarantee a quick decrease of the photon desorption yields and so a fast vacuum conditioning, it has been proposed to use localized SR absorbers along the vacuum chamber, spaced about 5 m apart. This would also help contain the high-energy Compton-scattered secondaries once the beam energy is increased up to 182.5 GeV, later in the experimental program. In the preliminary design of FCC-ee vacuum chamber absorbers presented in this work, the SR thermal power is intercepted along around 100 mm of slanted surface. The temperature distribution in the adsorbers is estimated by Finite Element Analysis (FEA) and needs to be assessed to avoid any liquid-gas phase change within the water-cooling circuit. The cooling channels contain a twisted tape that increases the turbulence of water. This results in the desired heat transfer coefficient. The mechanical deformations due to the non-uniform temperature map are presented and analysed as well.

Pulse power plasma stimulation: A technique for waterless fracturing, enhancing the near wellbore permeability, and increasing the EUR of unconventional reservoirs

The inherent characteristic of unconventional and ultra-low permeability reservoirs is a small drainage area that negatively affects the production rate and ultimate recovery (UR). Drilling horizontal wells, coupled with a stimulation process such as hydraulic fracturing, are applied to wells in these reservoirs to enhance well productivity. Although hydraulic fracturing has been the most famous stimulation technique in these reservoirs and has contributed to the increased US oil and gas production during the last several years, other stimulation techniques may be competitive with (or complementary to) hydraulic fracturing. This is because the main contribution to production in these reservoirs would be from complex fracture networks (often micro-cracks) combined with enhanced formation permeability rather than the classical two-wing fractures. Hence, a near-wellbore stimulation technique for improving the permeability of these reservoirs by activating the existing natural fractures and creating secondary microfractures would be highly desired. This paper investigates the pulse plasma stimulation technique to investigate such an approach of waterless stimulation/fracturing that creates multiple fractures and is also a permeability enhancement method. In this method, plasma is generated by discharging a high voltage and high current electrical energy in a very short time into two electrodes submerged in a wellbore filled with aqueous fluid. This study is divided into two sections. The first part presents experimental and numerical examples of stimulation/fracturing induced by pulse plasma in different rocks. Several parameters, including the effect of discharge with and without wire, input energy, confining stress, and rock type, on the induced fractures are studied. The second part uses the insights and results from the first part to numerically investigate pulse plasma's effects on production. Measurement of the formation permeability around the generated fractures indicated that the shock wave generated multiple fractures and increased the rock permeability by more than one or two orders of magnitude. The second part of the numerical section discusses the increased estimated rate and ultimate recovery (EUR) of horizontal wellbores due to fracturing and modified permeability resulting from pulse plasma. We present a sensitivity analysis on the magnitude and extent of the improved permeability region and its impact on EUR.

Quantum Chemical Studies of Sensitizers Designed for Dye-Sensitive Solar Cells

In this study, two different organic dyes with a D-π1-R-π2-A structure were designed from the reference dye E0 with a D-π1-π2-A structure (E3-E4). By adding 2,3-dicyanopyrirazinophenanthrene between the π-bridges on the reference dye E0 and changing the π-bridge, dyes designed to examine the photovoltaic features for use in dye-sensitized solar cell (DSSC) devices were obtained. Various properties of the designed dyes, such as their geometrical structures, absorption spectra, nonlinear optical properties (NLOs), energy levels, boundary molecular orbitals, and some photovoltaic and chemical reactivity parameters, were investigated using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods to improve the performance of Dye-Sensitized Solar Cells (DSSCs). The calculated theoretical results concluded that E4 of the designed dyes can have a high short-circuit current and better power conversion energy (PCE) compared with E0. These results indicate that adding different auxiliary ligands and modifying the π-bridges can effectively improve the photovoltaic performance of the system.

In vivo flexible energy harvesting on porcine heart via highly-piezoelectric PIN–PMN–PT single crystal

One of the main challenges with implantable biomedical devices is the replacement surgeries of depleted batteries for elderly patients. This not only poses medical risks but also results in financial burdens. Consequently, there is a growing need for self-powered in vivo electronics that can convert the biomechanical movements of organs into usable electric energy. Notably, a previously reported in vivo flexible energy harvester generated relatively low current output from a living porcine heart, restricting its ability to operate self-powered electronic devices. In this study, a high current output implantable flexible energy harvester was demonstrated by adopting a highly-piezoelectric single crystal Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PMN–PT) film. The in vivo flexible energy harvester generated a short-circuit output current of 20 µA (corresponding to a current density of 3.08 µA/mm3) from the contraction and relaxation of a porcine heart. This recorded in vivo output current density was attributed to its outstanding piezoelectric charge coefficient of the single crystal PIN-PMN-PT, optimized Ni stressor assisted exfoliation as well as the implementation of a metal-insulator-metal (MIM) structure. Moreover, the flexible energy harvester was also demonstrated as a self-powered cardiac sensor to monitor irregular heartbeats by observing heart rate variations due to drug administration in a porcine heart. Additionally, output performance evaluation was conducted with the chest closed to further assess the feasibility of practical in vivo harvesting. Finally, the single crystal harvester exhibited biocompatibility, showing no signs of cytotoxicity based on cell viability assessments and histological characterizations. These results underscore the potential of the flexible PIN-PMN-PT energy harvesting device as a sustainable power source for self-powered in vivo biomedical electronics.

On the dependence structure of European vegetable oil markets

ABSTRACT In light of current high and volatile energy and food prices, we examine the daily dynamics of the conditional variance-covariance matrix and price discovery in European vegetable oils. We find that energy prices chiefly influence vegetable oil trends, while stock-to-use ratios significantly impact variance-covariance dynamics when considering their specific cold filter plugging point (CFPP). This technical detail robustly demonstrates interplays among vegetable oils based on economic principles of complementarity and substitutability, even amid the pandemic and the Russian-Ukrainian conflict. Moreover, both marginal distributions and volatility dependence structures relate to distinct economic fundamentals, enhancing our understanding of the market’s complexity.

STUDY ON THE DISPOSAL OF WASTE FROM THE HYDROGEN GENERATION BY ALUMINUM OXIDATION IN ALKALINE SOLUTION

In face of the current high energy consumption and demand worldwide, a change to a sustainable energy matrix became one of the pillars for global sustainability. The use of renewable energy has been one of the most attractive subjects in recent years. Several public policies in this matter have been suggested and there are ongoing efforts toward their implementation. The United Nations (UN) proposed what is called the 2030 Agenda, which considers 17 Sustainable Development Goals (SDG) to be achieved by the year 2030. In support of the 2030 Agenda, research on the production of fuels from clean and sustainable sources is being conducted by the scientific community around the world. Fossil fuels are finite and also a major source of environmental pollutants, therefore the choice of using renewable sources of energy tends to be an increasingly growing and attractive alternative. Hydrogen is a fuel with a high heating value and is known as the most abundant gaseous element and simplest in chemical structure. The scientific community researching fuel cells has given much attention to the generation and storage of hydrogen. Besides the electrolytic hydrogen production and the reforming of fossil fuels (e.g., natural gas), hydrogen can be generated by metallic means, for example, by oxidation of aluminum in an alkaline solution. The use of recyclable metals, such as aluminum in this study, is an option for sustainable hydrogen generation processes. Nevertheless, like any chemical reaction, part of the products generated are waste, and some are even harmful to the environment, which makes the production of sustainable fuels unfeasible in case of not finding an appropriate technological industrial destination for such waste. The herein study comprises the investigation of the industrial and technological applications of the products of the hydrogen generation reaction from aluminum. Mastering the chemical reaction parameters of that reaction is paramount for the optimal design of a hydrogen generation system. The disposal of the waste is relevant since it makes the energy supply chain complete and sustainable.

Eco-friendly Resistive Plate Chambers for detectors in future HEP applications

Resistive Plate Chamber detectors are largely used in current High Energy Physics experiments, typically operated in avalanche mode with large fractions of Tetrafluoroethane (C2H2F4), a gas recently banned by the European Union due to its high Global Warming Potential (GWP). An intense R&D activity is ongoing to improve RPC technology in view of future HEP applications. In the last few years the RPC EcoGas@GIF++ Collaboration has been putting in place a joint effort between the ALICE, ATLAS, CMS, LHCb/SHiP and EP-DT Communities to investigate the performance of present and future RPC generations with eco-friendly gas mixtures. Detectors with different layout and electronics have been operated with ecological gas mixtures, with and without irradiation at the CERN Gamma Irradiation Facility (GIF++). Results of these performance studies together with plans for an aging test campaign are discussed in this article.