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Al2O3/ZrO2 (A/Z) layers with embedded Pt nanoparticles (Pt-nps) at the interface of A/Z have been used to create a dielectric film with an enhanced permittivity. The Pt-nps and dielectrics are both grown by the atomic layer deposition process, which is complementary metal–oxide–semiconductor compatible. In order to control the thickness ratio of Pt-nps in the overall dielectrics more easily, the thickness of the ZrO2 layer is changed from 12 to 30 nm with a fixed thickness of 12 nm for Al2O3 and constant growth cycles of 70 for Pt-nps. The results show that the introduction of Pt-nps is beneficial to the enhancement of the dielectric permittivity. As the thickness of ZrO2 is 30 nm, the capacitance density increases from 2.5 to 5.1 fF/μm2 with the addition of Pt-nps, i.e., a doubling of the capacitance density achieved. Additionally, the leakage current at 2 V increases from 1.1 × 10−8 to 1.5 × 10−7 A/cm2. Furthermore, the dielectric breakdown field decreases from 5.4 to 2.7 MV/cm. The electric field distribution simulation and charging–discharging test imply that interfacial polarization is built at the interface of Pt-nps and the dielectric films, which contributes to the dielectric permittivity enhancement, and local electric field increasing in the affinity of Pt-nps gives rise to the deterioration of the leakage current and breakdown electric field. [ABSTRACT FROM AUTHOR]

The motion of ions in supercapacitor electrodes produces internal stresses that cause viscoelastic strains. In addition, stresses may be due to external forces applied to structural supercapacitors, which are multifunctional materials that simultaneously store energy and carry structural loads. There are currently no thermodynamics-based models for the coupled electro-chemo-viscoelastic response of electrodes. Here, the same thermodynamics model is used for both the viscoelastic response and the electrochemical response. This mathematical equivalence is a reference from which to study coupling between the viscoelastic and electrochemical responses. The model has two inputs (stress or strain and electric potential or specific charge) and two outputs (strain or stress and specific charge or electric potential). The coupling is studied by adding three constants in the free energy. The convexity of the free energy and the stability of the free response limit the magnitude of the coupling. The unit response matrix is derived, and results are given for the time and frequency domains. The effect of an applied potential on stress is shown to be much more significant than the converse effect. The model compares well to an experiment consisting of a cyclic electric current applied during stress relaxation. [ABSTRACT FROM AUTHOR]

We study the impedance behavior of two ferrofluids, of a similar magnetic material, one constituted by spherical nanoparticles and the other constituted by cubes, both suspended in kerosene. The ferrofluid constituted by cubic nanoparticles has 10% doping of a rare earth ion. The samples were inserted between two parallel disk-like electrodes of area S = 2.3 c m 2 made of surgical steel, separated by d = 127 μ m. The impedance was measured by applying a sinusoidal voltage of amplitude V 0 = 30 mV, from 1 mHz to 100 kHz. To analyze the experimental data, we use a model based on the Poisson–Nernst–Planck equations, with Ohmic boundary conditions. In the analysis, we assume that the ferrofluids contain free ions, originated from the manufacturing process, released by the stabilization layer around the magnetic nanoparticles dispersed in kerosene. The corresponding nanoparticles are charged of opposite signs with respect to these free ions. In the high frequency region, the effective diffusion coefficient coincides with that from the free diffusion coefficients, defined as the mathematical average between the diffusion coefficients of the nanoparticles and the free ions. In the low frequency region, we found the ambipolar diffusion coefficient, defined as their harmonic average. The effect of the electrodes is taken into account by means of surface conductivity to describe the conduction current across the electrode, assumed to be proportional to the surface electric field. In this model, the role of the electrodes is important just in the low frequency region. On the contrary, in the high frequency region, where the electric current is dominated by the displacement current, the role of the electrodes is negligible. The results show that the nanoparticles of the magnetic material have no effects on the higher-frequency range of the impedance spectra. In the low frequency region, our results indicate a difference in the electric response of the two ferrofluids. Due to their similar dimensions and, hence, similar ambipolar diffusion coefficients, we impute the observed different behavior to the charge transfer from the bulk to the external circuit included in the surface conductivity. [ABSTRACT FROM AUTHOR]

Polyurethanes have been extensively studied for their strong electromechanical response. Previous studies have mainly investigated the impact of electrical charges on these polymers' DC conductivity, which was measured on the order of 10−10 S/m. The movement of electric charges is responsible for the macroscopic deformation of polymer films under an electric field. However, this study focused primarily on electric fields below 107 V/m, where the electric current complies with Ohm's law. In this paper, we examine the electric current above this field value and observe a deviation in the current from linearity with the applied field, especially for a high electric field of 106–107 V/m. This change is known in polymers under high electric fields but has never been observed in polyurethane. This suggests the injection of electrode charges into the polymer material. This article provides the threshold at which the transition occurs from linear (Ohm's law) to nonlinear conduction as a result of injected electric charges. [ABSTRACT FROM AUTHOR]

A series of (Gd, Y, Yb, Tb, Ce)3Al2Ga3O12 compositionally disordered compounds with a garnet structure were prepared in the form of ceramics by sintering in oxygen at 1650 °C for 2 h and studied for the luminescent properties and interaction of ions entering the matrix host. The luminescence features of Ce3+ ions were found to be strongly dependent on the Yb concentration. Photoluminescence and scintillation kinetics are characterized by subnanosecond kinetics when the Yb index in the compound exceeds X = 0.3. It opens an opportunity to create an extremely fast and dense scintillation material emitting in a visible range. A further decrease in the Yb index in the compound leads to an increase in the intensity of Yb3+ infrared (IR) emission, whereas Ce3+ and Tb3+ ions contribute to the luminosity of the material by overlapping intra- and intereconfiguration luminescence bands in the spectral range of 300–700 nm. This finding opens an opportunity to create converter materials tolerant to the corpuscular radiation of isotope sources, providing a high efficiency of electric current production when coupled with a silicon photovoltaic element. The compounds were engineered at the nanoscale level, providing control over electronic excitation transfer between luminescent ions. [ABSTRACT FROM AUTHOR]

A non-destructive method for detecting sub-micrometer-sized micropipes on an entire wafer surface is investigated. Since it is difficult to detect sub-micrometer-sized micropipes due to their small core size, a non-destructively and accurately detecting method is required. To solve the issue, we focus on a characteristic depression generated around micropipes, namely, line-shaped depressions. In this paper, the location of line-shaped depressions is identified by using optical inspection, and the line-shaped depressions are distinguished whether micropipes exhibit line-shaped depression or not by using mirror electron microscope observation as high-resolution inspection. The accuracy of the distinction results is confirmed by scanning electron microscope observation, and electrical characteristics of the P–N diode are fabricated using the inspected wafer. Furthermore, the sub-micrometer-sized micropipes are observed at the sites of leakage current identified by emission microscopy. Additionally, device simulation of the blocking-voltage characteristics of P–N diodes suggests that the increase in leakage current depends on the electric field at the sub-micrometer-sized micropipes, regardless of their core size. [ABSTRACT FROM AUTHOR]

Unlike popular multiband antenna array radiation based on either electric or magnetic surface currents, the use of mutually interleaved and tightly coupled electric and magnetic currents results in an aperture-reuse space-efficient multiband radiating surface for highly integrated antenna-frontend architecture and spatial power combining design scenarios. In this work, slot and dipole modes corresponding to magnetic and electric currents are effectively interleaved and excited in a surface to develop a space-efficient dual-wideband aperture-shared radiating surface. In this case, due to an effective reuse of the antenna aperture over both frequency bands, a high aperture-reuse efficiency is achieved. First, we devise a planar magneto-electric (ME)-dipole-alike antenna and analyze it in both the frequency and time domain. The antenna is then studied by the characteristic mode theory and the findings are validated using full-wave simulations. The developed planar ME-dipole-alike antenna is used to realize a dual-wideband radiating surface in which electric and magnetic currents are mutually coupled and interlaced, which is excited by properly oriented and distributed sources on the antenna's surface. Eventually, a highly isolated dual-wideband prototype was developed and fabricated using a cost-effective multi-layer Printed Circuit Board (PCB) process that operates in the Ku-band with both impedance and gain bandwidth of approximately 42% and in the Ka-band with respective impedance and gain bandwidth of 29% and 16.32%. [ABSTRACT FROM AUTHOR]

This paper proposes a maximum torque per ampere (MTPA) control method for a permanent magnet reluctance hybrid rotor dual stator synchronous motor (PMRHRDSSM) based on a sliding mode speed controller, in response to the complex and special electromagnetic relationship of the motor. The paper focuses on the special electromagnetic relationship of PMRHRDSSM with stator winding series structure. Firstly, the trajectory equation of PMRHRDSSM MTPA stator current vector is derived, and based on the relationship between PMRHRDSSM torque and reluctance dq‐axis current, a PMRHRDSSM current controller that meets MTPA constraints is designed. Afterwards, a PMRHRDSSM sliding mode speed controller was designed with input speed error and output reference torque. Finally, an experimental platform for the proposed control method was established, and the control method was experimentally validated. [ABSTRACT FROM AUTHOR]

Background In December 2021, the BIOFISH 300 SUL method for the determination of total sulfites in shrimp was adopted as a First Action Official Method of AnalysisSM by the AOAC INTERNATIONAL. Objective A collaborative study was conducted in February 2023 in order to test the reproducibility of the method. Methods The method is based on the use of a benchtop biosensor device that relates the concentration of sulfite to a quantifiable electric current signal. The sensing element, the Biotest, harbors an enzyme that specifically oxidizes sulfite, and the reaction products are electrochemically detected by the device in less than 3 min. The sulfite is extracted from the solid using an aqueous-based buffer solution, which ensures that all sulfite is present as a free anion. Results Eleven collaborators participated in the study of nine different shrimp samples. Values of repeatability and reproducibility relative standard deviation (RSDr and RSDR) obtained from the statistical analysis of valid data ranged from 2.1–8.1% and 7.5–14.3%, respectively, for shrimp samples above the quantification limit of the method, set at 7 mg/kg. Conclusion These results showed good repeatability and reproducibility of the method, even at concentrations below the legal threshold for sulfite in food, where the reference optimised Monier-Williams (OMW) method shows relatively high imprecision. Highlights On the basis of these results, the enzymatic amperometric biosensor method developed by BIOLAN Microbiosensores was adopted as Final Action Official Method in September 2023. [ABSTRACT FROM AUTHOR]

AbstractTemperature and voltage are critical operational parameters that significantly influence the efficiency of the electro-osmosis dewatering process. Despite their importance, there is a lack of comprehensive research to evaluate their combined effects on enhancing electro-osmotic dewatering process efficiency. In this study, mutual effects of temperature and voltage on electro-osmotic dewatering of tailings were investigated using numerical simulation. To validate the model, output data were compared with experimental results on thermal electro-osmotic dewatering of red mud. The results indicated that increase in temperature from 25 °C to 35 °C and 25 °C to 45 °C resulted in a 12% and 27% increase in electric current, and 25% and 50% increase in fluid outflow velocity, respectively. Additionally, electric current and fluid outflow velocity increased by about 50% and 100% for all considered temperatures when voltage increased from 10.5 V to 15.75 and 10.5 V to 21 V, respectively. Furthermore, the results proved that increase in temperature was more effective than voltage in enhancing Joule’s heating-induced dewatering. The study also revealed that increase in distance between electrodes by more than 1 m decreases the efficiency of electro-osmotic dewatering. [ABSTRACT FROM AUTHOR]

Energy consumption has emerged as a hot topic and cutting-edge research theme in the application of electro-osmotic consolidation of low-permeability soils. However, the resistance of circuits in an electro-osmotic consolidation system is complex, whereby electric energy can be converted into various forms of energy. Based on the law of energy conversion, this study proposes a new method for the quantitative evaluation of energy conversion in an electro-osmotic consolidation system. The most important energy created during electro-osmotic consolidation is the molecular migration kinetic energy, which can drive the drainage of water and cations and the consolidation of soil, which is referred to as the effective energy consumption (EEC). The second form of energy is interfacial thermal energy (ITE), which is associated with increasing interfacial resistance. The third form of energy is the soil thermal energy (STE), which is associated with the rising temperature of the system due to the passage of electric current. In the experiments conducted here, the EEC proportion was overestimated by 57–80% in the electro-osmosis process without considering the ITE and STE. The efficiency of electro-osmotic drainage can be considerably enhanced if appropriate measures can be taken to reduce the proportion of ITE and STE. [ABSTRACT FROM AUTHOR]

The efficient processing of hypereutectic Al–Si alloys depends on controlling the microstructure of the primary Si phase during solidification. This study investigates the effects of electric current and phosphorus (P) addition on the refinement of primary Si, with the results confirming that applying electric current during solidification refines the primary Si phase; introducing P further enhances this refinement. Notably, when 10 ppm of P is added (below the identified critical amount of 20 ppm), an improved refinement effect is observed compared with the application of either electric current or P alone. Applying an electric current generates a circulating flow within the melt, resulting in an increased cooling rate, which leads to improved nucleation behavior for the primary Si phase. In addition, the circulating flow generated within the melt influences the dispersion of aluminum phosphide during nucleation. Adding P at concentrations above 40 ppm does not yield further benefits, suggesting a saturation point for its efficacy. This study demonstrates that the concurrent electric current application and minimal P addition can significantly enhance the refinement of primary Si phases, offering a potent approach for optimizing the microstructural properties of hypereutectic Al–Si alloys. [ABSTRACT FROM AUTHOR]

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]

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]

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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]

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]

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]

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]

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]

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]

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]

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]

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]

Introduction Methods Results Conclusion Various catheter designs are appearing for Pulsed Field Ablation (PFA). It is unclear if they differ in terms of safety and efficiency. PFA studies have reported hemolysis, kidney injury, high troponin, among other side effects.Using a CT‐derived computer model, we compared catheter designs using two metrics: (1) efficiency: power delivered to an atrial wall target, expressed as a percent of total generator power; and (2) safety: electric current to achieve 90% transmurality (since more energy causes more collateral effects), as well as the corresponding electrode current density (ECD), a heat and bubble metric. The following catheter designs were compared: penta‐spline basket, Nitinol spheres (focal 9 mm and large 1‐shot), circular, balloon, and flex‐circuit. Target was a 6 × 47 mm circumferential segment of atrial wall at LPV antrum. Transmurality was defined as percent of target having >600 volts per centimeter (V/cm) electric field needed for electroporation.Efficiency was 0.9, 1.4, 2.7, 5.9, 10, and 12% for the large 1‐shot and 9 mm Nitinol spheres, penta‐spline, circular, flex spline, and balloon catheters, respectively. Regarding safety, currents for 90% transmurality were 70, 39,36,12.5, 5.3, and 4 Amps for the same respective catheters, with less being safer. ECD was 124, 25, 74, 83, 41, and 31 A/cm2, respectively.Computer models demonstrated a remarkable range in efficiency among catheters studied. Those having less atrial blood exposure had the highest efficiencies, with factors of up to 13X more efficiency compared to exposed ones. Higher efficiency designs have less collateral current and are safer. Confirmatory in‐vivo studies are required. [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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.)

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]

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 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.)

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]

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]

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]

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]