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Commercialization of rechargeable lithium‐ion (Li‐ion) batteries has revolutionized the design of portable electronic devices and is facilitating the current transition to electric vehicles. The technological specifications of Li‐ion batteries continue to evolve through the introduction of various high‐risk liquid electrolyte chemicals, yet critical evaluation of the physical, environmental, and human health hazards of these substances is lacking. Using the GreenScreen for Safer Chemicals approach, we conducted a chemical hazard assessment (CHA) of 103 electrolyte chemicals categorized into seven chemical groups: salts, carbonates, esters, ethers, sulfoxides–sulfites–sulfones, overcharge protection additives, and flame‐retardant additives. To minimize data gaps, we focused on six toxicity and hazard data sources, including three empirical and three nonempirical predictive data sources. Furthermore, we investigated the structural similarities among selected electrolyte chemicals using the ChemMine tool and the simplified molecular input line entry system inputs from PubChem to evaluate whether chemicals with similar structures exhibit similar toxicity. The results demonstrate that salts, overcharge protection additives, and flame‐retardant additives contain the most toxic components in the electrolyte solutions. Furthermore, carbonates, esters, and ethers account for most flammability hazards in Li‐ion batteries. This study supports the complementary use of quantitative structure–activity relationship models to minimize data gaps and inconsistencies in CHA. Integr Environ Assess Manag 2024;20:2231–2244. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: Chemical hazard assessment was conducted for 103 electrolyte chemicals, categorized into seven groups, used in lithium‐ion batteries.Most of the 103 electrolyte chemicals exhibited high levels of concern relative to human health and environmental hazard endpoints.Nonempirical predictive data sources are essential for filling data gaps commonly encountered in empirical data sources.Structure similarity analysis highlights that chemicals with structure similarity correlate with similar hazard endpoints, increasing the value of predictive data sources. [ABSTRACT FROM AUTHOR]

As the automotive industry undergoes a significant transition toward electric vehicles (EV), the matter of electric current discharge in motor bearings has emerged as a focal point of concern. This issue has gathered increased attention due to its potential to inflict damage upon bearing surfaces. The extent of damage inflicted by the discharges is intricately tied to the discharge energy, a factor directly influenced by both bearing capacitance and discharge voltage. In pursuit of a deeper understanding of discharge voltage dynamics within EV motor bearings, electric discharge tests were conducted using in-house modified single ball-on-disk contact and full bearing test equipment. Our test results at the single ball-on-disk contact show that discharge voltage adheres to a probabilistic distribution. Moreover, parallel investigations at the bearing level have yielded corroborative findings, reinforcing conclusions drawn from the single contact tests. These collective efforts contribute to a comprehensive understanding of electric discharge phenomena in motor bearings, essential for developing effective mitigation strategies and advancing the reliability of EV propulsion systems. [ABSTRACT FROM AUTHOR]

We report the Magnetospheric Multiscale (MMS) observation of a bifurcated reconnecting current sheet in Earth's dayside magnetosheath. Typical signatures of the ion diffusion region, including sub-Alfvénic demagnetized ion outflow, super-Alfvénic electron flows, Hall magnetic fields, electron heating, and energy dissipation, were found when MMS traversed the current sheet. The weak ion exhaust at the current sheet center was bounded by two current peaks in which super-Alfvénic electron flow directed toward and away from the X line were observed, respectively. Both off-center current peaks were primarily carried by electrons, one of which was supported by field-aligned current, while the other was mainly supported by current driven by electric field drift. The two current peaks also exhibit other differences, including electron heating, electron pitch angle distributions, electron nongyrotropy, energy dissipation, and magnetic field curvature. An ion-scale magnetic flux rope was detected between the two current peaks where electrons showed field-aligned bidirectional distribution, in contrast to field-aligned distribution parallel to the magnetic field in two current peaks. The observed current sheet was embedded in a background shear flow. This shear flow worked together with the guide field and asymmetric field and density to affect the electron dynamics. Our results reveal the reconnection properties in this special plasma and field regime which may be common in turbulent environments. [ABSTRACT FROM AUTHOR]

This study aims to tackle the challenge of explaining the underlying mechanisms behind the time-varying impedance phenomenon in animals experiencing low-voltage electric shocks. A dynamic impedance model that considers the effect of water electrolysis (WEDI) has been developed. First, we conducted root cause analyses through progressive validation experiments, identifying water within the shocked body as the key factor influencing impedance variation. Monitoring hydrogen concentration above the electrodes and measuring mass changes in the shocked body revealed that the time-varying impedance is closely related to internal water electrolysis. Second, we quantitatively analyzed the impact of water molecule decomposition during electrolysis on the salt concentration and conductivity within the electrically shocked body. A mathematical relationship between the variable resistance within the body and time was derived. A dynamic impedance model for animal electric shock that considered the effects of water electrolysis was subsequently established, explaining the underlying mechanism behind the time-varying impedance phenomenon. Finally, the Mean Absolute Percentage Error (MAPE), Mean Absolute Error (MAE), and Root Mean Square Error (RMSE) between the electric shock current predicted by the WEDI model and actual measurements were 0.00357, 0.00350, and 0.00446. Compared to existing models, the WEDI model demonstrates superior accuracy and interpretability. [ABSTRACT FROM AUTHOR]

Due to the push for carbon neutrality in various human activities, the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant. Also, the challenge lies in achieving microwatt‐scale outputs due to the inherent conductivity of the materials and diverting electric currents. To address this challenge, our research has concentrated on utilizing nonconductive mediums for water‐based low‐cost microfibrous ceramic wools in conjunction with a NaCl aqueous solution for power generation. The main source of electricity originates from the directed movement of water molecules and surface ions through densely packed microfibrous ceramic wools due to the effect of dynamic electric double layer. This occurrence bears resemblance to the natural water transpiration in plants, thereby presenting a fresh and straightforward approach for producing electricity in an ecofriendly manner. The generator module demonstrated in this study, measuring 12 × 6 cm2, exhibited a noteworthy open‐circuit voltage of 0.35 V, coupled with a short‐circuit current of 0.51 mA. Such low‐cost ceramic wools are suitable for ubiquitous, permanent energy sources and hold potential for use as self‐powered sensors and systems, eliminating the requirement for external energy sources such as sunlight or heat. [ABSTRACT FROM AUTHOR]

To control the spin wave (SW) propagation, external energy sources such as magnetic fields, electric currents, or complex nanopatterning are used, which can be challenging at the deep nanoscale level. In this work, we overcome such limitations by demonstrating SW propagation in Pt/Co multilayers at a remanent state controlled by stripe domain patterns, using Brillouin light scattering and micromagnetic simulations. We show that parallel stripes with a periodicity around 100 nm exhibit reconfigurability, as the stripes can be rotated by applying the in-plane field without damaging their shape. This allows us to study SW propagation perpendicular and parallel to the stripes. We observe multimodal SW spectra—three bands in perpendicular and five in parallel geometry. Numerical results allow us to identify all observed modes and to explain the differences between two configurations by the unequal contribution of all three magnetization components in the SW dynamics. We find that the experimentally measured non-reciprocal dispersion (for the wavevector perpendicular to the stripes) is not the breaking of time-symmetry but the asymmetry in intensity of the measured signals of two different low-frequency modes, which is due to the inhomogeneous SW amplitude distribution over the multilayer thickness and the limited light penetration depth. Our results pave the way for easy reprogrammability and high energy efficiency in nanomagnonics. [ABSTRACT FROM AUTHOR]

The assessment of trafficability for planetary rovers in relation to non-geometric hazards is a crucial issue in deep space exploration. This study relies on terramechanics theory and incorporates actual data from Mars soil and rover parameters to develop a model that accurately represents the interaction between the rover's wheels and Martian soil. Through numerical simulations, this model specifically investigates the relationship between the current of the rover's wheel drive motor and factors such as slip ratio, soil pressure parameters, and soil shear parameters. Terrestrial experiments are also conducted to verify the precision of certain numerical calculations. The proposed wheel–soil interaction model, based on wheel motor current, provides a foundation for assessing non-geometric trafficability and the inversion of planetary soil parameters. [ABSTRACT FROM AUTHOR]

The electrical conductivity and volt–ampere characteristics (VAC) of the p-CuTlS2 single crystal with specific resistance ρ = 4 0 Ω ⋅ cm and irradiated by γ -quantum were studied in the range of 100–300 K temperature and 10–104 V/cm. It was determined that the cause of the conduction disorder observed in the CuTlS2 single crystal at low electric fields and high radiation doses is the formation of defect clusters dominated by cation vacancies. A sharp increase in current at high electric fields and temperatures occurs as a result of thermo-field ionization of the acceptor level with activation energy Δ E a = 0. 0 8 eV and the ionization voltage decreases with increasing radiation dose. Based on the determination of the parameters (λ , r m , n 0 , ε) that determine the mechanism of current flow, the dependence of the shape of the potential hole on the radiation dose was determined. [ABSTRACT FROM AUTHOR]

This study utilizes first-principle density functional theory (DFT) to explore the high-pressure behavior of 4-hydrazine benzene sulfonamide. Our investigation, spanning pressures from 0 to 300 GPa, delves into diverse properties of the crystal (C6H9N3O2S), encompassing the crystal structure, band gap, density of states, permittivity, and conductivity. Under increasing pressure, intriguing observations emerge. Distortions in the molecular structure manifest notably at 70, 130, and 270 GPa, accompanied by distinctive anisotropic behavior in lattice constants. Notably, our scrutiny of the band gap and density of states exposes a transition from a semiconductor to a metallic state and back to a semiconductor state, illuminating the profound influence of pressure on the material's electronic structure. At 0 GPa, the real part of permittivity registers negative values within the 15.6–20.2 eV energy range, suggesting the crystal's inability to propagate light and its manifestation of metallic reflection properties. Conversely, at 270 GPa, the imaginary part of permittivity indicates metallic characteristics within the electronic structure, alongside a substantial energy loss in the crystal's real part of conductivity. Moreover, the imaginary part of conductivity unveils pronounced energy conversion between the driving electric field and current excitation, hinting at structural instability under this extreme pressure. This research contributes vital insights into the behavior of hydrocarbons under high pressure, filling crucial gaps in our understanding of their properties. [ABSTRACT FROM AUTHOR]

The tailward high‐speed flows, in which various kinetic processes and magnetic structures can be embedded, are usually produced by the magnetic reconnection in the Earth's magnetotail. Here, using high‐resolution measurements from the Magnetospheric Multiscale (MMS) mission, we report an intense current in the tailward high‐speed flow. The current density can reach ∼180 nA/m2 and is primarily carried by electrons. Taking advantage of the First‐Order Taylor Expansion (FOTE) method, we reveal that such an intense current is associated with a ribbon‐like magnetic structure. A large electric field, reaching ∼90 mV/m, is also observed at the magnetic structure. The Hall term dominates the electric field, however, the contribution from the pressure gradient term and the electron inertial term is nonnegligible and can lead to strong energy conversion (E ⋅ J > 2 nW/m3) through the synergistic action with the intense current. This study improves the understanding of the current behaviors and energy conversion associated with magnetic structures in the Earth's magnetotail. Plain Language Summary: As products of the magnetotail magnetic reconnection, the earthward and tailward high‐speed flows can be usually observed as associated with a variety of kinetic processes and magnetic structures. Here, for the first time, we report an electron‐carried intense current associated with a ribbon‐like magnetic structure in the tailward high‐speed flow, by using high‐resolution MMS data and the First‐Order Taylor Expansion (FOTE) method. Encountering a large electric field with a nonnegligible contribution from the pressure gradient term and electron inertial term, such intense current leads to a strong energy conversion at the ribbon‐like magnetic structure. This study shed light on how the intense current is associated with the ribbon‐like magnetic structure and how the strong energy conversion is driven at such a structure, which complements the knowledge of the energy conversion process in the Earth's magnetotail. Key Points: An electron‐carried intense current (J > 180 nA/m2) is observed in association with a ribbon‐like structure in the tailward high‐speed flowA large electric field, with nonnegligible contribution from pressure gradient and electron inertial term, is observed at such a structureThe intense current and large electric field work together to drive a strong energy conversion (E ⋅ J > 2 nW/m3) at this structure [ABSTRACT FROM AUTHOR]

In response to the safety and stability issues of current electric vehicle charging connection devices, this study proposes a charging system planning for electric vehicles with different capacity charging piles based on the user behavior characteristics of electric vehicles and Monte Carlo methods. It is found that the predicted results under the set management strategy are most consistent with the trend of actual load changes. Moreover, in the prediction of weekly load, the research strategy has better performance than traditional unmanaged strategies. Under the research scheme, the average charging speed of charging piles with capacity of A and B in the peak period was 41.4 min/ and 18.8 min/, respectively, which increased by 29.3% and 11.7% respectively compared with 58.6 min/ and 21.3 min/ in the normal period. The total economic cost of the research plan was 4.871 million yuan, which was 67.0 million yuan and 3.833 million yuan lower than the control methods 1 and 2, respectively. The total number of charging stations of types a and b that need to be purchased for the research method decreased by 18.47% and 63.24% compared to the comparative method 3. The results indicate that the research method significantly improves the utilization rate of charging stations in the electric vehicle charging system. This study has important application value in the intelligent management of electric vehicle charging systems. [ABSTRACT FROM AUTHOR]

A one-dimensional charge-density wave (CDW) is driven to slide by a dc electric field, carrying an electric current. In an additional ac field with frequency ω ex , it is known that the sliding CDW can be synchronized to ω ex , leading to the occurrence of Shapiro steps in the I–V characteristics. Motivated by a recent experiment where ac fields with two frequencies ω ex and ω ex ′ are simultaneously applied, we theoretically investigate the effects of frequency mixing on the Shapiro-step formation. Based on the Fukuyama–Lee–Rice model, we show that in addition to the main steps induced by ω ex , satellite steps characterized by ω ex ′ emerge. It is also found that with increasing the ac-field strength for ω ex ′ , each step width first exhibits a damped oscillation as in the one-frequency case and then exhibits a non-monotonic behavior. The origin of these behaviors and the relevance to the associated experiment are also discussed. [ABSTRACT FROM AUTHOR]

The current electric vehicle domain is increasingly focused on fuel cell technologies due to its flexibility, steady supply of power, low atmospheric pollution, increased startups, and rapid responses. Fuel cells exhibit nonlinear power versus current characteristics, making it challenging to extract maximum peak power from the fuel stack. To address this, this work introduces an adaptive Coati Optimization algorithm combined with a Tilt-integral-derivative (TID) controller (TID-ACOA) to find the maximum power point (MPP) of the fuel stack systems, ensuring maximum power extraction. The proposed MPPT controller is compared with other MPPT controller, including PI, TID, and TID-COA. Comprehensive evaluations are conducted on tracking current, voltage, maximum power extraction, MPPT controller efficiency, converter voltage settling time, and oscillations. The fuel stack's low output voltages are enhanced using a boost DC-DC converter, and the entire fuel stack-fed boost converter systems is modeled using MATLAB/Simulink. Simulation result show that the TID-ACOA MPPT controller achieves higher MPP tracking efficiency compared to conventional controllers. [ABSTRACT FROM AUTHOR]

The incommensurate charge density wave states (CDWs) can exhibit steady motion in the flow limit after depinning, behaving as a nonequilibrium system with time-dependent states. Since the moving CDW, like an electric current, breaks both time-reversal and inversion symmetries, one may speculate the emergence of nonreciprocal nonlinear responses from such motion. However, the moving CDW order parameter is intrinsically time-dependent in the lab frame, and it is known to be challenging to evaluate the responses of such a time-varying system. In this work, following the principle of Galilean relativity, we resolve this time-dependent hard problem in the lab frame by mapping the system to the comoving frame with static CDW states through the Galilean transformation. We explicitly show that the nonreciprocal nonlinear responses would be generated by the movement of CDW states through violating Galilean relativity. [ABSTRACT FROM AUTHOR]

Flash events, which are electric power spikes occurring under an electric field and temperature above the threshold, can significantly accelerate mass diffusion over short periods of time. This study investigated the surface structure of the (001) surface of strontium titanate single-crystal treated by flash events caused by direct current (DC) and alternating current (AC) electric fields from a viewpoint of surface-related mass diffusion. The surface structuring caused by flash events was significantly different among DC and AC electric fields. The DC-flash event destabilized surface steps, causing them to wander and form surface mounds with a height of several tens of nanometers. In addition, numerous two-dimensional (2D) nuclei with a size of several nanometers are formed on the terraces. In contrast, the AC-flash event stabilized surface steps without the formation of surface mounds, causing them nearly straight with uniform terrace width at approximately 500 nm. 2D nuclei with a size of a few 10 nm were formed at the step edges with round shapes. Both methods were confirmed as evidenced by the formation of two-dimensional nuclei on the surface after the flash events, to enhance surface-related mass diffusion. [ABSTRACT FROM AUTHOR]

Transparent alumina ceramics produced by pulsed electric current sintering (PECS) include black dots, which can be observed with the naked eye. These black dots have porous structures caused by the aggregates in the raw powder. In order to investigate the detailed mechanism of black dot formation, transparent alumina ceramics were prepared by sintering α-alumina granules to produce large pseudo-aggregates and introducing them into α-alumina powder for PECS. Macroscopic black dots were formed in the sample. Characteristic Raman peaks of graphite were detected in porous parts of these macroscopic black dots. Analysis of gas phases generated from graphite sheets for PECS suspected to be involved in carbon contamination showed CO and CO 2 generation. In thermodynamic calculations on carbon activity during PECS, gas phase including CO and CO 2 generated from the hot graphite mold/sheet permeates the porous part of the cold sample, and the carbon activity of gases including CO and CO 2 on the porous surface theoretically exceeds unity. Then, CO is adsorbed and decomposed on the porous surface, resulting in carbon contamination. The formation of macroscopic black dots is caused by carbon deposition in agglomerates of the raw powder from CO generated by graphite sheets during PECS. [ABSTRACT FROM AUTHOR]

Does inventing representations in open-ended computational environments contradict the goal of acquiring canonical scientific knowledge? We analyze the computational models of electric conductors that N = 35 eight-grade students built with a NetLogo-based microworld. Students used the microworld to sketch structures that represent models of electric conductors and then observed the resulting electric current. We use data from classroom discourse, computer log files and questionnaires, to identify different ways through which students used the platform, and how their engagement in construction, explains the variance in their learning gains. We found differences in the number and types of models that students constructed in the microworld: while most students built the models that were intended by the instructors, some added unconventional doodling models, that deviated from the intended structures. We found that students who built more models made larger gains in conceptual knowledge about electric current. However, we also found that students who constructed more unconventional models, produced lower learning gains on items that assessed the particle-level mechanism of electrons in conductors. [ABSTRACT FROM AUTHOR]

The alloying elements in 8Cr4Mo4V bearing steel tend to form large primary carbides with carbon, which not only causes element segregation but also becomes the primary source of fatigue crack initiation, thereby decreasing the material's usability and machinability. Owing to the excellent thermal stability of primary carbides, traditional homogenization annealing requires high temperatures, which is both time‐ and energy‐intensive. Excessively high heat treatment temperatures can also result in “overburning” of the sample. Herein, primary carbides are rapidly dissolved at low temperatures using pulsed electric current treatment. The additional free energy introduced by the pulsed electric current lowers the thermodynamic barrier for carbide dissolution. During the second‐phase dissolution process, the unbalanced diffusion of elements may cause the formation of Kirkendall voids. Due to the difference in electrical conductivity between the voids and the matrix, the pulsed electric current generates thermal compressive stress on the voids, promoting rapid atom migration to these voids and accelerating their healing. This pulse‐current treatment technology offers a novel method for the rapid dissolution of carbides in alloys at low temperatures and for the rapid healing of related voids. [ABSTRACT FROM AUTHOR]

Centrosymmetric materials with site inversion asymmetries possess hidden spin polarization, which remains challenging to be converted into spin currents because the global inversion symmetry is still conserved. This study demonstrates the spin-polarized circular photocurrents in centrosymmetric transition metal dichalcogenide semiconductors at normal incidence without applying electric bias. The global inversion symmetry is broken by using a spatially-varying circularly polarized light beam, which could generate spin gradient owing to the hidden spin polarization. The dependence of the circular photocurrents on electrode configuration, illumination position, and beam spot size indicates an emergence of circulating electric current under spatially inhomogeneous light, which is associated with the deflection of spin-polarized current through the inverse spin Hall effect. The circular photocurrents is subsequently utilized to probe the spin polarization and the inverse spin Hall effect under different excitation wavelengths and temperatures. The results of this study demonstrate the feasibility of using centrosymmetric materials with hidden spin polarization and non-vanishing Berry curvature for spintronic device applications. The authors report the generation of circular photocurrents from multilayer 2H-phase transition metal dichalcogenides, including MoTe2, MoS2, and WSe2, which is attributed to the manifestation of hidden spin polarization and inverse spin Hall effect. [ABSTRACT FROM AUTHOR]

Storm-time ionospheric electrodynamics effects have been the subject of extensive studies. The solar wind/magnetosphere/ionosphere and thermosphere disturbance wind dynamos have long been identified as the main drivers of low latitude storm-time electrodynamics. Extensive detailed studies showed that climatology of low latitude disturbance electric fields and currents is in good agreement with results from global theoretical and numerical models. Over the last decade, however, numerous studies have highlighted that the response of low latitude electrodynamics to enhanced geomagnetic activity is significantly more complex than previously considered. It is now clear that the electrodynamic disturbance processes are affected by a larger number of solar wind and magnetospheric parameters and that they also have more significant spatial dependence. This is especially pronounced during and after large geomagnetic storms when multiple simultaneous disturbance processes are also active. In this work, we briefly review the main past experimental and modeling studies of low latitude disturbance electric fields, highlight new results, discuss outstanding questions, and present suggestions for future studies. [ABSTRACT FROM AUTHOR]

The merits of compressed air energy storage (CAES) include large power generation capacity, long service life, and environmental safety. When a CAES plant is switched to the grid-connected mode and participates in grid regulation, using the traditional control mode with low accuracy can result in excess grid-connected impulse current and junction voltage. This occurs because the CAES output voltage does not match the frequency, amplitude, and phase of the power grid voltage. Therefore, an adaptive linear active disturbance-rejection control (A-LADRC) strategy was proposed. Based on the LADRC strategy, which is more accurate than the traditional proportional integral controller, the proposed controller is enhanced to allow adaptive adjustment of bandwidth parameters, resulting in improved accuracy and response speed. The problem of large impulse current when CAES is switched to the grid-connected mode is addressed, and the frequency fluctuation is reduced. Finally, the effectiveness of the proposed strategy in reducing the impact of CAES on the grid connection was verified using a hardware-in-the-loop simulation platform. The influence of the k value in the adaptiveadjustment formula on the A-LADRC was analyzed through simulation. The anti-interference performance of the control was verified by increasing and decreasing the load during the presynchronization process. [ABSTRACT FROM AUTHOR]

In this work, we analyzed the temperature dependence of the current-voltage characteristics of the structure of glass/Mo/p-Sb2Se3/n-CdS/In. From an analysis of the temperature dependences of the direct branches of the I-V characteristic of the heterojunction, it was established that the dominant mechanism of current transfer at low biases (3kT/e0.8 V, the dominant current transfer mechanism is Newman tunneling. In the case of reverse bias (3kT/e

A large part of the cost of steel production in the world is related to the consumption of graphite electrodes. Electrode is the only material that maintains its electrical conductivity at high temperatures, and hence it is used as a conductor of electric current in EAF furnaces. Considering the high costs of graphite electrodes, any action that leads to reducing the consumption of graphite electrode can lead to increasing the productivity of steelmaking operations. In this study and as its novelty, the electrophoretic method was used to generate a ceramic coating for the protection of graphite electrodes. Electrophoretic deposition (EPD) is a two-step process in which charged particles suspended in a suspension move towards the oppositely charged electrode under the influence of an electric field which combine as a dense film on the surface. In the EPD technique, the particle size limit is not very important if a stable suspension is formed and micro and nano-sized particles can be used in this method. The numerical simulation of the thermal contour on the graphite electrode was done in ABAQUS software. Moreover, the surface morphology of graphite samples has been investigated via scanning electron microscopy (SEM). The created coating was a combination of Al2O3 and SiO2, which was placed on the surface of test samples by EPD treatment. The obtained results have the properties of resistance to thermal shock and show the increase in the life of coated graphite samples at different temperatures and times. [ABSTRACT FROM AUTHOR]

The development of low-temperature solid oxide fuel cells (LT-SOFCs) is gaining abundant interest in semiconductor ionic materials (electrodes and electrolytes). Following this concept, an A-site deficiency technique is employed to unilaterally change BaTiO 3 to regulate ionic conduction, further improving the electrolyte's performance. The electrolytes, namely BaTiO 3 , Ba 0·95 TiO 3 , and Ba 0·90 TiO 3 , have carefully been constructed and studied utilizing solid-state ball milling. The A-site deficiency in BaTiO 3 resulted to improve the ionic conductivity and minimize activation energy. This can be attributed to the higher number of oxygen vacancies on the surface and at the interfaces. The enhanced morphology, direct visualization of lattice structures, and the existence of oxygen vacancies caused by A-site deficiency have been studied in detail. Out of all the prepared electrolytes, Ba 0·90 TiO 3 shows an enhanced fuel cell performance of 625 mW/cm2. In comparison, the Ba 0·95 TiO 3 achieved a reasonable fuel cell performance of 573 mW/cm2, and BaTiO 3 achieved 548.40 mW/cm2 at a low temperature of 550 °C. Compensating for the lack of A-site ions is a successful approach to improve ion transportation in fuel cells without creating any leakage of electric current. This is achieved by modifying the arrangement of energy bands that control the movement of charge carriers. The results of this work demonstrate that A-site-deficiency engineering can be used to improve the electrolyte performance of LT-SOFCs, making it a promising method for advancing fuel cell technologies in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

This study explores the impact of end electric current on the performance of a marine magnetohydrodynamic (MHD) propulsion motor or thruster using a comprehensive 3D numerical simulation. The investigation focuses on various operating parameters, such as electromagnetic and drag forces, efficiency, losses, current, and different pressure components. To validate the numerical findings, a scaled-down experimental setup is utilised. The results demonstrate that certain operating parameters of MHD motors are not affected by the three-dimensional characteristics of their channels. These parameters, including fluid velocity, can be accurately calculated using the analytical model based on the effective electric current of the motor. Conversely, other operating parameters of MHD motors are significantly influenced by the end effects in their channels. For example, the overall efficiency, which depends on the total electric current of the motor, should be calculated using a more precise simulation method. [ABSTRACT FROM AUTHOR]

When radon emanates, the conductivity in surface air increases, which causes variation in the electric field not only in the lower atmosphere, but also in the ionosphere. There have been proposals to use such ionospheric disturbances as earthquake precursors. The ionospheric electric fields are calculated using a quasi-stationary model of an atmospheric conductor including the ionosphere. Earlier, we showed that even with extreme radon emanation, electric field disturbances in the E- and F-regions of the ionosphere are several orders of magnitude smaller than the supposed earthquake precursors and smaller than the fields usually existing there, which are created by other generators. In this paper, we focus on the D-region. In the vertical component of the electric field strength, the main contribution to the D-region comes from the fair-weather field. It is shown that in the D-region, the vertical electric field component over the area of intense radon emanation can double in comparison with the fair-weather field. A detailed spatial pattern of disturbances of electric fields and currents in the atmosphere and ionosphere over the radon emanation region is constructed. [ABSTRACT FROM AUTHOR]

Electron transport characteristics were measured at room temperature applying nanosecond duration electrical pulses on two-dimensional electron gas (2DEG) channel in AlGaN/GaN heterostructures grown on SiC substrate. Crystal lattice self-heating effects were minimised by usage of nanosecond duration pulses being as short as 2 ns. We were able to reach highest current densities of 1.24 A/mm and 1.80 A/mm for different type of AlGaN/AlN/GaN and AlGaN/GaN heterostructures under the electric field of 57 kV/cm and 69 kV/cm, respectively. Even stronger electric field usage was allowed by the pulse source employed (up to 75 kV/cm for channel length of 12.5 μ m), however, that was not needed as the electric current near saturation was observed. The three-dimensional (3D) electron channels in GaN epilayer on GaN substrate were also investigated under pulsed electric field reaching up to 216 kV/cm. The electron drift velocity was found from experimental charge current density characteristics assuming that Hall electron density does not change in the sample under high electric fields. Maximum drift velocities for the 2DEG channels in AlGaN/GaN and AlGaN/AlN/GaN samples were found to be up to 1.2 × 10 7 cm/s at 69 kV/cm and 1.1 × 10 7 cm/s at 57 kV/cm, respectively, while, the highest value of ∼ 2.6 × 10 7 cm/s at 216 kV/cm was obtained for the 3D GaN channels. In the region of high electric fields the electron drift velocity in 2DEG channel was smaller than that in 3D channel as the result of stronger hot-phonon effect. [ABSTRACT FROM AUTHOR]

A DC-DC converter plays a vital role in the On-Board Charger for Electric Vehicles (EVs). Also, having the capability for bidirectional power flow for a DC-DC converter is essential for EVs to transfer power from Vehicle-to-Grid (V2G) and Vehicle-to-Vehicle (V2V). In this context, this paper proposes a bidirectional DC-DC converter for the On-Board Charger for Electric Vehicles (EVs). The proposed DC-DC converter has two paths: a lossy partial path through two bridges, a high-frequency transformer, and a lossless direct path directly connecting the source to the output. A 7.8 kW DC-DC converter is developed in MATLAB/Simulink. The performance of the converter is analysed for various operating scenarios. Further, a scaled-down hardware prototype of the proposed converter with a power rating of 600 W has been developed. The dSPACE controller is used to control the power flows. The prototype is tested under various operating conditions. The experimental and simulation results show that the power flow through the direct path is around 58 % and through the partial path around 42 %. Due to this, the overall converter efficiency of 97.8% during charging and 95.6 % during discharging cycles has been achieved. Also, as only 42 % of power flows through the partial path, all the components' ratings and sizes are significantly reduced. Also, the distinguishing feature is its bidirectional power flow capability, making the EV capable of V2V and V2G power transfer. Hence, the proposed DCDC converter is an efficient and compact solution for an On-Board Charger for EVs. [ABSTRACT FROM AUTHOR]

Magneto-electric effect, i.e. an appearance of magnetisation induced by electric current, is allowed by symmetry in metals with crystal structure without space inversion. The microscopic origin of this effect is spin–orbit coupling of electrons with a non-centrosymmetric crystal lattice lifting spin degeneracy of electron energy and mixing spin and orbital degrees of freedom. The presented here calculation of magnetisation induced by current is based on the application of kinetic equation for the matrix distribution function of electrons occupying the states in two bands split by the spin–orbit interaction. [ABSTRACT FROM AUTHOR]

To date, new prototype device for directly converting chemical energy into electricity is still the most important pursuit although various types of fuel cells have been developed/commercialized. In this work, a novel (101¯0$10\bar{1}0$) orientated ZnO single crystal device is reported that generates electricity using the usual redox reactions. The principle of the device is similar to that of a photovoltaic device, known as a chem‐voltaic device. The air‐KBH4 chem‐voltaic device has an open‐circuit voltage (Voc) of 2.14 ± 0.007 mV and a short‐circuit current (Isc) of 1.44 ± 0.007 µA. The Voc and Isc increase to 2.24 mV and 2.81 µA, respectively, by preadding H2O2. A similar phenomenon is also observed when glucose is used to substitute KBH4. When KBH4 or glucose solution is added to the ZnO (101¯0$10\bar{1}0$) surface, it reacts with chemisorbed oxygen to produce free electrons. Due to the presence of the spontaneous electric field (Es) in the polar [0001] azimuth of ZnO, these free electrons move along the [0001] direction, producing an electric current. So chemical energy is converted into electricity. This finding opens up research on the chem‐voltaic cell. [ABSTRACT FROM AUTHOR]

A polymer electrolyte membrane is a core component of proton exchange membrane fuel cell. Since the ionic conductivity of polymer electrolyte membrane depends on water content, it is necessary to understand the water transport mechanism in the polymer electrolyte membrane. When the electric current demand is varied rapidly, the transient water transport results in the shortage or flooding in the polymer electrolyte membrane. The transient behavior of water transport in the polymer electrolyte membrane is nonlinear due to the water sorption/desorption mechanism. In this study, the nonlinear water transport mechanism of polymer electrolyte membrane is established to understand the transient behavior of water transport over the rapid change of electric current. Since the nonlinear dynamics delay the response of water transport under rapid change of electric current, system-level simulation is conducted to evaluate the system response by delayed water transport. Results show that the rapid change of electric current dramatically affects the water transport dynamics. As a result, this study confirms that water transport in the electrode is delayed depending on the polymer electrolyte membrane (PEM) thickness and that flooding occurs in the cathode depending on the relative humidity at the anode inlet. [ABSTRACT FROM AUTHOR]

Keratinocytes play an essential role in the inflammatory phase of wound regeneration. In addition to migrating and proliferating for tissue regeneration, they produce a large amount of cytokines that modulate the inflammatory process. Previous studies have shown that subthermal treatment with radiofrequency (RF) currents used in capacitive resistive electric transfer (CRET) therapy promotes the proliferation of HaCat keratinocytes and modulates their cytokine production. Although physical therapies have been shown to have anti-inflammatory effects in a variety of experimental models and in patients, knowledge of the biological basis of these effects is still limited. The aim of this study was to investigate the effect of CRET on keratinocyte proliferation, cytokine production (IL-8, MCP-1, RANTES, IL-6, IL-11), TNF-α secretion, and the expression of MMP9, MMP1, NF-κB, ERK1/2, and EGFR. Human keratinocytes (HaCat) were treated with an intermittent 448 kHz electric current (CRET signal) in subthermal conditions and for different periods of time. Cell proliferation was analyzed by XTT assay, cytokine and TNF-α production by ELISA, NF-κB expression and activation by immunofluorescence, and MMP9, MMP1, ERK1/2, and EGF receptor expression and activation by immunoblot. Compared to a control, CRET increases keratinocyte proliferation, increases the transient release of MCP-1, TNF-α, and IL-6 while decreasing IL-8. In addition, it modifies the expression of MMPs and activates EGFR, NF-κB, and ERK1/2 proteins. Our results indicate that CRET reasonably modifies cytokine production through the EGF receptor and the ERK1/2/NF-κB pathway, ultimately modulating the inflammatory response of human keratinocytes. [ABSTRACT FROM AUTHOR]

Integrated zirconium (Zr) alloy fuel claddings require low-temperature and high-efficiency joining technologies for nuclear applications. However, conventional direct-joining technologies make it challenging to satisfy critical requirements at relatively low temperatures in a short time. As a promising alternative, the electric-current-assisted joining (ECAJ) method was studied to reduce the joining temperature and time required for the direct joining process. ECAJ was performed on a spark plasma sintering apparatus, with the specimens assembled with and without graphite dies in the two models. The microstructural evolution and mechanical properties of Zr/Zr joints were investigated at 600 − 900 °C for 1 s to 30 min under a pressure of 30 MPa using different configurations with or without a graphite die. While the joint quality varied with the joining conditions, no significant phase transformation, abnormal grain growth, or preferential orientation was observed at the interface. The maximum shear strength of 404 ± 78 MPa and hardness of 370.9 ± 49.8 HV were achieved at 600 °C for 10 min using a die-less configuration. The joining mechanism was discussed in terms of the potential thermal and electric effects inside the specimen, with the low-temperature joining mechanism attributed to the combined effect of transient overheating and electric-field-accelerated element self-diffusion at the interface, with the latter playing a leading role. [ABSTRACT FROM AUTHOR]

The current technology for curing high-performance composites, such as those used in industries like such as aeronautics and the automotive industry, is based on the use of autoclaves, where the material is cured by external heating, in large ovens. This type of curing requires enormous amounts of energy, of which only a small part is invested in the actual curing of the material, and the rest is mainly used for heating and maintaining the temperature of the autoclave. An alternative method that entails a lower energy cost compared to the traditional methodology is curing through the Joule effect, in which an electric current is passed through the material, so that it acquires temperature from the inside due to the passage of current through the carbon fibres, triggering and accelerating the curing process of the composite. While Joule curing may provide a much more efficient and faster curing, a control technology is needed to ensure that temperatures all throughout the composite match the temperature programme. In this work, a procedure has been developed to control the Joule effect curing of carbon fibre/epoxy composites in order to compare, by means of differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), the curing obtained by this method with that obtained by the traditional oven curing method. [ABSTRACT FROM AUTHOR]

With the advent of Big Data, traditional digital computing is struggling to cope with intricate tasks related to data classification or pattern recognition. To mitigate this limitation, software‐based neural networks are implemented, but they are run in conventional computers whose operation principle (with separate memory and data‐processing units) is highly inefficient compared to the human brain. Brain‐inspired in‐memory computing is achieved through a wide variety of methods, for example, artificial synapses, spiking neural networks, or reservoir computing. However, most of these methods use materials (e.g., memristor arrays, spintronics, phase change memories) operated with electric currents, resulting in significant Joule heating effect. Tuning magnetic properties by voltage‐driven ion motion (i.e., magnetoionics) has recently emerged as an alternative energy‐efficient approach to emulate functionalities of biological synapses: potentiation/depression, multilevel storage, or transitions from short‐term to long‐term plasticity. In this perspective, the use of magnetoionics in neuromorphic applications is critically reviewed, with emphasis on modulating synaptic weight through: 1) control of magnetization by voltage‐induced ion retrieval/insertion; and 2) control of magnetic stripe domains and skyrmions in gated magnetic thin films adjacent to solid‐state ionic supercapacitors. The potential prospects in this emerging research area together with a forward‐looking discussion on future opportunities are provided. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) continue to evolve, and sales continue to increase as the world pushes toward improved sustainability. This drives the need for research to understand the unique environments in which fluids operate within the Electric Drive Units (EDUs) of EVs in order to improve durability and reduce frictional losses. However, for this to happen, test rigs are required to operate with an electric current passing across the test parts and through the lubricant. Very few electrified test rigs currently exist, with most being adaptations of rigs undertaken by academia and independent and national research labs. In this work, the PCS Mini Traction Machine (MTM) was modified to supply a voltage across a tribological contact. New parts for the MTM were designed in collaboration with the instrument manufacturer. Work was undertaken in both the author's labs and the manufacturer's labs with the aim of bringing a commercially available unit to market as quickly as possible. A test matrix was completed on the MTM utilizing a range of temperatures, loads, and voltage inputs for three different lubricants commonly used in EDUs. The test matrix consisted of 36 test conditions, with some runs performed in triplicate, resulting in 81 tests for each oil and a total matrix of 243 tests. The test matrix was run to obtain the results and to test the robustness of the rig design. After testing was completed, the MTM disc wear scars were measured. The results from these measurements indicate that the application of alternating current (AC) and direct current (DC) causes a significant increase in the wear scar compared to non-electrified test conditions. This, in turn, results in increased traction values under non-electrified conditions. It was also noted that the repeatability of the traction curves and end-of-test wear was reduced under both AC and DC electrified conditions. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examined the effect of high-density pulsed electric current (HDPEC) treatment on the residual stress relief of martensitic stainless steel SCS6. The findings indicate that applying HDPEC at 100 A/mm2 for 370 ms, or equivalent current conditions at a maximum temperature of approximately 735 °C, can nearly eliminate surface residual stresses. Moreover, this treatment resulted in a 7 pct increase in strength without deteriorating the ductility. X-ray diffraction and electron backscatter diffraction analysis found that defects (i.e., dislocations) within the grains were remarkably removed, which was the main reason for the residual stress removal. This study demonstrates the feasibility of HDPEC in eliminating residual stresses of martensitic stainless steels, presenting a promising alternative to traditional heat treatment. In addition, this method introduces possibilities for localized non-destructive treatments on substantial components, enabling rapid and straightforward repairs. [ABSTRACT FROM AUTHOR]

Copyright of Current Retina Journal / Güncel Retina Dergisi is the property of Anadolu Kitabevi Basim Yayim Medikal Turizm Kirtasiye Tic. Ltd. Sti. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geomagnetic disturbances (GMDs) are rapid fluctuations in the strength and direction of the magnetic field near the surface of the Earth which can cause electric currents to be induced in the ground. The geomagnetically induced currents (GICs) can cause damage to pipelines and power grids. A detection algorithm has been developed to identify rapid changes in 10 s averaged magnetometer data. This higher resolution data is important in capturing the most rapid changes associated with extreme GIC events. The algorithm has been used on an array of ground‐based magnetometers from SuperMAG data from 2010 to 2022, creating a new list of global GMDs. Data from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) is used to place the observed GMDs in the context of the global pattern of magnetosphere‐ionosphere field‐aligned currents (FACs). A dawn sector population of GMDs is found to lie near the boundary between the region 1 and region 2 FACs, while a pre‐midnight sector population is found to occur poleward of the FAC boundary on region 1 upward FACs. It is also shown that the latitude of the GMDs expands with the FAC boundary and their occurrence peaks around 77° magnetic latitude. Plain Language Summary: Rapid changes called geomagnetic disturbances (GMDs) in the Earth magnetic field can lead to currents flowing at the surface of the Earth. When these currents flow through infrastructure such as power grids and pipeline, damage can occur which can lead to a loss of services and impact society. It therefore important to understand the conditions necessary for these current to form. The rapid changes can be measured by ground magnetometers. A newly developed algorithm that uses 10 s data from 2010 to 2022, from SuperMAG magnetometers around the globe, has been developed. The GMDs are then places in context to the field aligned currents (FACs) measure by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) that flow in the magnetosphere. A population that is found to occur at dawn lies equatorward of the FAC boundary. A population of GMDs found to occur at pre‐midnight lie poleward of the FAC boundary. The latitude that the GMDs occur at is dependent on the FAC boundary. Key Points: An algorithm has been developed to identify geomagnetic disturbances in 10 s magnetometer dataGeomagnetic disturbances occur mainly in two populations, pre‐midnight, on region 1 upward field‐aligned currents (FACs) and dawn on the boundaryThe latitude that the geomagnetic disturbances occur at is dependent on the FAC boundary [ABSTRACT FROM AUTHOR]

The wind dynamo in the ionosphere leads to differential motion of ions and electrons, which in turn sets up electric fields and currents. Observations show that daytime lower thermospheric horizontal winds have large vertical gradients. Numerical modeling conducted approximately 50 years ago demonstrated that the zonal wind shears in the ∼130–180 km altitude range can generate off‐equatorial relative minima (dips) in the daytime height‐integrated eastward current density, appearing as westward sidebands north and south of the equatorial electrojet (EEJ). This study observationally confirms this connection for the first time by combining Ionospheric CONnection explorer zonal wind profiles and Swarm latitudinal zonal currents. We demonstrate observationally that the magnitude of the EEJ sideband current is proportional to the strength of westward turning winds with altitude in the Pedersen conductivity dominated region. Additional numerical experiments explain the importance of wind shear in different altitude regions in generating the sideband current. This study contributes to the better understanding of the neutral wind effect on the local current generation. Plain Language Summary: The winds in the E‐region ionosphere push the plasma in the presence of Earth's magnetic field, causing ions and electrons to move separately, producing electric current. The low‐latitude ionospheric current system consists of an intense eastward current at the magnetic equator (called Equatorial Electro‐Jet (EEJ)) and off‐equatorial reduced eastward or relative westward currents (EEJ sideband currents) in both hemispheres. Modeling studies have shown that the altitudinal gradient of the zonal wind is related to the strength of the EEJ sideband currents. However, observational studies to validate these results have been missing to this date. This study utilizes simultaneous observations from Ionospheric CONnection explorer and Swarm satellites to provide insights on the connection between low‐latitude winds and currents, which will improve our understanding of the causes of daytime ionospheric variability. Key Points: First observational evidence of effect of zonal wind gradients at ∼130–180 km on low‐latitude Equatorial Electro‐Jet sideband currentsThe altitude variation of the zonal wind gradient modulates the latitudinal variation of EEJ sideband currentsWith increasing westward wind shear, the strength of low‐latitude Equatorial Electro‐Jet sideband current increases [ABSTRACT FROM AUTHOR]

Chrome plating of long bars in conventional batch plants proves to be challenging, requiring complex lifting equipment and considerable vertical space. Therefore, the use of continuous chrome plating plants, which allow controlled passage of the bars through the chrome plating bath, is preferred. The continuous hard chrome plating plant operates automatically, controlling the entire process from the loading to the discharge of chrome plated bars. The feed and discharge mechanisms must allow the flow of electric current through the bars subject to the chrome plating. This calls for the design of some mechanisms capable of ensuring a constant feed of bars and their efficient discharge. This paper presents a virtual study using finite element analysis (FEA) focused on the strength assessment of the mechanism including the drive pin, the levers and the sliding plates responsible for the movement of the bars. As a result of the study, essential data on critical stresses, local deformations and factor of safety (FOS) for the whole mechanism were obtained, thus providing valuable information for the optimization of the chrome plating process. [ABSTRACT FROM AUTHOR]

The magnetotail plasma sheet boundary layer (PSBL) is a dynamic boundary layer between the hot‐denser plasma sheet and the cold‐tenuous tail lobes. It plays an important role in exchanging mass and energy in the magnetotail. In previous studies, the local current carried by the electron beams has been well understood. The strong energy conversion (E ⋅ J, E is electric field and J is current density), however, is barely reported at the PSBL. Here, using magnetospheric multiscale mission, we find a strong dawn‐dusk current with a magnitude of 80 nA/m2 at the magnetotail PSBL. The strong current appears during crossing the PSBL and is primarily contributed by the perpendicular electron currents. Cooperating with an intense fluctuating electric field (reaching ∼40 mV/m) carried by the lower‐hybrid drift waves, this dawn‐dusk current leads to a strong energy conversion with a magnitude larger than 3 nW/m3. This study enhances the understanding of local energy‐conversion processes at the PSBL. Plain Language Summary: As a spatial boundary layer between the plasma sheet and tail lobes, the magnetotail plasma sheet boundary layer (PSBL) has been widely thought of as an important channel for mass and energy exchanged in the magnetotail. In this study, we report a strong dawn‐dusk current (J > 80 nA/m2) at the PSBL by utilizing the magnetospheric multiscale mission. Such a strong current is contributed by electron currents in the perpendicular directions and leads to strong energy conversion (E ⋅ J > 3 nW/m3) at the PSBL through the interaction with the intense electric field (E > 40 mV/m) associated with the lower‐hybrid drift waves. Our results improve the understanding of the energy conversion at the PSBL. Key Points: A strong dawn‐dusk current with a magnitude of 80 nA/m2, primarily contributed by electron currents, is observed at the magnetotail plasma sheet boundary layer (PSBL)The lower‐hybrid drift waves are observed at the PSBL and carry an intense fluctuating electric field which can reach ∼40 mV/mSuch current and electric field leads to strong energy conversion at the PSBL, with a magnitude of larger than 3 nW/m3 [ABSTRACT FROM AUTHOR]

Lightning is the severest threaten to safe operation of wind turbines. In this letter, the authors present the first altitude‐triggered lightning experiment involving an elevated 12 m‐long wind turbine blade placed on the ground. A total of 50 precursors with amplitude over 62.9 A were observed through measurements of channel‐base current, fast electric field, and optical data. The air gap with around 3–5 m has been bridged between the wire's lower extremity and the metal blade tip during ascending of the rocket and it is observed to be luminous by slow framing rate camera. The precursors are classified into three groups, namely bipolar pulses, unipolar pulses, and group pulses. Excluding the precursors preceding the initial stage and M‐components at the late‐time of the initial stage, five stages are classified. In the first stage, the current remains limited at a relatively small value, while the electric field exhibited a slow rising behavior with positive polarity. In the second stage, the current starts to increase, and the electric field rapidly intensifies due to the accumulating charge, and the wire is assumed to experience an explosion. In the third stage, the reconnection process occurs. The current is characterized by a peak value of 1.45 kA with 10%–90% risetime of 10.4 μs. The electric fields suffer from notable decrease and are characterized by a microsecond‐scale V‐shape pulse. The current cutoff is quite short that almost not found. In the fourth step, the current is characterized by superimposed pulses. The final stage is the channel darkening. Plain Language Summary: Observation results are reported in detail about the altitude‐triggered lightning experiment involving an elevated 12 m‐long wind turbine blade placed on the ground. There are fruitful precursors prior to the beginning of the initial stage. The precursors demonstrate that the air gap with around 3–5 m has been bridged between the wire and the metal blade tip. The precursors are grouped into three groups, namely bipolar pulses, unipolar pulses, and group pulses. The initial stage is classified into five periods. The triggering wire is believed to be vapourized during the second stage. The so‐called initial current variation (ICV), also called reconnection process, occurs at the third stage. The superimposed pulses are found immediately after the reconnection process in the fourth stage. The late‐time of the initial stage is also characterized by superimposed pulses associated with M‐components. This work is potentially helpful to understand the physical process lightning strikes a wind turbine, and design lightning protection strategies for wind turbines. Key Points: First altitude‐triggered lightning experiment associated with an elevated 12 m‐long wind turbine blade has been conducted through simultaneous measurements of current, electric fields and optical dataThe 50 precursors over 62.9 A proceeding the initial stage are classified into three groups: (a) bipolar pulses with the notably initial positive peak and followed by the negative excursion; (b) unipolar pulses with the notably initial positive peak but with quite flat late‐time response; and (c) group pulsesFive stages associated with channel reestablishment are classified according to the measured current and electric field, in which the current cutoff is quite short that almost not found [ABSTRACT FROM AUTHOR]

Cold atmospheric plasma (CAP) has been shown to be beneficial in various medical fields such as wound healing, oncology or dentistry. A prominent effect induced by CAP is the boost of microcirculation in human skin tissue. Being a complex cocktail of physical and chemically reactive components, the mechanisms by which CAP enhances microcirculation still remain unclear. Thus, this study aims to identify relevant CAP components involved in stimulation of dermal microcirculation. In a comparative approach, the application of the same CAP source was modified in such a way that three different treatment modalities could be realized, each with a characteristic composition of electrical current flow and concentration of reactive species. Microcirculation parameters oxygen saturation (StO2), tissue hemoglobin index, near-infrared perfusion index and tissue water index were recorded before and after each treatment on the lateral proximal left arm of 10 healthy volunteers by means of hyperspectral imaging. The maximum microcirculatory response to CAP was observed when all components were allowed to interact with skin tissue (standard treatment). In contrast, no upregulation was found as soon as electric currents and fields had been removed from the effective component spectrum. Application of the CAP source at reduced concentrations of reactive species compared to standard treatment led to significant but less pronounced enhancement of dermal microcirculation. The findings of this study indicate that a synergistic interplay of all CAP components promotes microcirculation in dermal tissue most effectively. Moreover, the findings support the hypothesis that electric currents and fields play a key role in enabling microcirculation boost whereas availability of reactive species in the gas phase is associated with the intensity of the tissue response to CAP treatment. [ABSTRACT FROM AUTHOR]

Integrating autonomous sensing materials into future applications necessitates developing advanced multiscale multiphysics predictive models. This study introduces an experimentally informed predictive framework for autonomous sensing architected materials, combining theoretical and computational methodologies. By incorporating stress‐dependent electrical resistivity through anisotropic piezoresistive constitutive effects, alongside considering material, geometric, and contact nonlinearities, the proposed multiscale model captures the architecture‐dependent piezoresistive responses of lattice composites produced via additive manufacturing of polyetherimide (PEI)/carbon nanotube (CNT) nanoengineered feedstock. The PEI/CNT composite exhibits exceptional strength (105 MPa), stiffness (3368 MPa), and strain sensitivity (gauge factor ≈13), translating into remarkable piezoresistive characteristics for the PEI/CNT lattice composites, surpassing existing works (gauge factor ≈3 to 11). This multiscale finite element model accurately predicts both macroscopic piezoresistive responses and the influence of architectural and topological variations on electric current paths, validated via infrared thermography analysis. Additionally, an Ashby chart for the gauge factor of PEI/CNT lattice composites suggests their prediction through a scaling law similar to mechanical properties, underscoring the tunable strain and damage sensitivity of these materials. The combined experimental, theoretical, and numerical findings offer critical insights into optimizing piezoresistive composites through architected design, with profound implications for smart orthopedics, structural health monitoring, sensors, batteries, and other multifunctional applications. [ABSTRACT FROM AUTHOR]

Context. In May 2024, the extremely complex active region National Oceanic and Atmospheric Administration (NOAA) 13664 produced the strongest geomagnetic storm since 2003. Aims.The aim of this study is to explore the development of the extreme magnetic complexity of NOAA 13664 in terms of its photospheric electric current. Methods. The non-neutralized electric current was derived from photospheric vector magnetograms, provided by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory. The calculation method is based on image processing, thresholding, and error analysis. The spatial and temporal evolution of the non-neutralized electric current of the region as well as its constituent subregions was examined. For context, a comparison with other complex, flare-prolific active regions is provided. Results. Active region NOAA 13664 was formed by the emergence and interaction of three subregions, two of which were of notable individual complexity. It consisted of numerous persistent, current-carrying magnetic partitions that exhibited periods of conspicuous motions and strongly increasing electric current at many locations within the region. These periods were followed by intense and repeated flaring. The total unsigned non-neutralized electric currents and average injection rates reached 5.95 ⋅ 1013 A and 1.5 ⋅ 1013 A/day, and are the strongest observed so far, significantly surpassing other super-active regions of Solar Cycle 24 and 25. Conclusions. Active region NOAA 13664 presents a unique case of complexity. Further scrutiny of the spatial and temporal variation of the net electric currents during the emergence and development of super-active regions is paramount to understand the origin of complex regions and adverse space weather. [ABSTRACT FROM AUTHOR]

In this work, fully densified Ni–SiC reinforced Ti6Al4V matrix composites were consolidated by pulsed electric current sintering (PECS) technique. The microstructural evolution and mechanical properties of the developed composites with varying SiC contents were investigated. The microstructural study revealed in-situ precipitation of TiC, Ti 5 Si 3 and Ti 3 SiC 2 strengthening phases within the composites. The α colony size in the composites was notably reduced compared to the fabricated SiC-deficient samples due to the addition of SiC additive into the Ti6Al4V alloy matrix. The in-situ precipitated phases enhanced the mechanical properties of the composites. Composite reinforced with 10 wt% SiC (TNi10SiC) displayed the highest hardness value of 609.8 ± 50.9 HV 0.5 among the sintered samples, translating to an increment of about 88 % compared to the unreinforced sample T. Among the sintered samples, the highest flexural strength of 2094.32 ± 97.67 MPa was obtained for the TNi5SiC composite, after which the flexural strength deteriorates with increasing SiC content as witnessed in TNi10SiC composite with the least flexural strength of 863.67 ± 71.57 MPa due to agglomeration of the reinforcement phases within the composite. Samples reinforced with 0 wt% SiC experienced a ductile fracture, and the composites containing 2.5 wt% - 5 wt% SiC content witnessed intergranular and interlamellar fractures. However, at higher SiC content, reinforcement pull-out and debonding of the agglomerated reinforcement phases predominates, and composites fail by brittle fracture. [ABSTRACT FROM AUTHOR]

The energy transported by the electric current that circulates a thermoelectric element (TE) varies with position due to the Joule and Thomson effects. The Thomson effect may enhance or compensate the Joule effect. A method for measuring the Thomson coefficient of a TE is presented. This method is based on the total compensation of the Joule and Thomson effects. The electric current then flows without delivering power to the TE or absorbing power from it. For a TE, the global Thomson/Joule compensation ratio Φ ¯ T / J is defined as the ratio of the power absorbed by the current due to the Thomson effect and the power delivered by the current to the TE due to the Joule effect. It can be expressed as Φ ¯ T / J = I 0 / I , where I is the electric current and I 0 is the zero-power current, a quantity that is proportional to the average Thomson coefficient. When I = I 0 , the Thomson effect exactly compensates the Joule effect and the net power delivered by the current to the TE is zero. Since the power delivered by the current is related to the temperature distribution, temperature measurements for currents around I 0 can be used as the basis for a measurement technique of the Thomson coefficient. With varying current, the difference between the temperature at the center of the TE and the mean temperature between its extremes reverses its sign at the zero-power current, I = I 0 . This observation suggests the possibility of measuring the Thomson coefficient, but a quantitative analysis is needed. With calculations using the constant transport coefficients model for B i 2 T e 0.94 S e 0.06 3   and B i 0.25 S b 0.75 2 T e 3 , it is theoretically shown that a null temperature detector with a sensitivity of the order of 1 mK allows for the accurate determination of the Thomson coefficient. [ABSTRACT FROM AUTHOR]