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Hybrid nanofluids were expressed by heat-transfer fluids into greater surface dispersion capabilities, stability and diffusion related for traditional nanofluids. The effort on the flow of volumetric entropy generation and convective heat transport of MHD hybrid nanofluid is considered. Hybrid nanofluid involves the field over the orderly stretchable surface for variable heat flux with the resistance of electric field. Effect on convective heating and nonlinear thermal radiation is again contained in the interpreted figure. Mathematical equations such as momentum, energy, conservation of mass and entropy were collected as conversion to governing partial differential equations by ordinary differential equations, utilizing similarity variables. An efficient finite element method (FEM) is used. Numerical calculations were accomplished for silver–magnesium oxide water (Ag-MgO/H2O) hybrid nanofluid and conventional silver water (Ag-H2O) nanofluid. The graphs were created by the temperature, velocity, and entropy profiles. to analyse the impact on governing parameters. These skin friction and heat transfer rates are analysed through regression analysis. The important allegation expressed by the hybrid Nanofluid has the best heat transfer rate, which is related to convectional nanofluid. Further, It raised the Brinkman number and Reynolds number and developed a total entropy of the structure. [ABSTRACT FROM AUTHOR]

Herein, we report the impact of external perturbation on the photocatalytic performance of g-C 3 N 4 /CoN 4 heterojunction and concomitant transition from type-I to type-II. The state-of-the-art theoretical modeling presented here is the first study on dynamic role of strain and electric field on g-C 3 N 4 /CoN 4 heterojunction and its potential application as a solar-driven water splitting reaction. Utilizing the density functional theory (DFT) calculation, V. N. et al. recently reported the photocatalytic activity of g-C 3 N 4 /MN 4 (M = Mn, Fe and Co) heterojunction [J. Comput. Chem. 2024 , 45 , 2518-2529, https://doi.org/10.1002/jcc.2746412 ] and subsequently established g-C 3 N 4 /CoN 4 as a type I heterojunction for photocatalytic water splitting reaction [Phys. Chem. Chem. Phys. 2024 , 26 , 21117–21133]. In the present study, we applied external perturbation in the form of mechanical strain, electric field and evaluated the electronic structure properties of the system along with the detailed examination of concomitant optical and magnetic properties of g-C 3 N 4 /CoN 4 heterojunction. The switching of photocatalytic feature from type I to type II originates due to the crossover between valence band maxima (VBM) of g-C 3 N 4 and CoN 4 in presence of external perturbation. Notably, the resulting system acts as a type II photocatalyst for water splitting reaction while applying compressive (negative) strain of −2 to −6% and an electric field of −0.5 and +0.5 V/Å, respectively. Accumulation of photogenerated electrons and holes separately in g-C 3 N 4 and CoN 4 units confirms the perceptible separation of charge carriers and thereby reduces the recombination compared to un-perturbed system. A red-shifted absorption maximum (689 nm), superior charge transfer (0.9e), and clear separation of photogenerated electrons and holes are the origin of enhanced photocatalytic efficiency of g-C 3 N 4 /CoN 4 heterojunction in the presence of external perturbation. We believe that our work will provide enough evidence to the experimentalists to achieve such a system in practice leading to human-friendly applications. Type II g-C 3 N 4 /CoN 4 heterostructure fabricated by an external perturbation strategy for efficient photocatalytic water splitting reaction. [Display omitted] • Density Functional Theory. • Theoretical Modelling of g-C 3 N 4 /CoN 4 heterojunction in presence of biaxial strain and electric field. • Photocatalyst for water splitting reaction. • Valence band crossover of g-C 3 N 4 and CoN 4 units. • Enhanced efficiency of solar energy conversion within the visible spectrum. [ABSTRACT FROM AUTHOR]

Cellular motility is essential for making and maintaining multicellular organisms throughout their lifespan. Migrating cells can move either individually or collectively by a crawling movement that links the cytoskeletal activity to the adhesion surface. In vitro stimulation by electric fields can be achieved by direct, capacitive or inductive coupled setups. We tested the effects of electrical stimulation provided by capacitive coupling on glioma cells, using a capacitive-coupled system powered by a potential difference of 35 V between two electrodes placed outside the culture dish. Numerical dosimetry identified two different fields: (i) in the order of 103 V/m at the level of the dielectric substrates, with almost uniform distribution; (ii) in the order of 10−1 V/m at the level of the culture medium, with spatial and material-dependent distribution. The scratch assay and the tracking of single-cell movement showed a boosted motility when crawling occurs on polystyrene surfaces, demonstrating the feasibility of this peculiar exposure system to generate forces capable of influencing cell behavior. [ABSTRACT FROM AUTHOR]

Valley polarization from broken inversion symmetry provides a new degree of freedom for carriers, bipolar magnetic semiconductor (BMS) generates a purely spin‐polarized current under a gate voltage, but few systems possess the coexistence of valley polarization and BMS. Based on the recent experimental FeCl2 flakes, reversible electric‐field effect on the valley‐ and spin‐polarized Janus FeClF bilayer with different stackings are investigated herein. Janus FeClF bilayers in all three stacks possess interlayer antiferromagnetic (AFM) and intralayer ferromagnetic (FM) couplings. The most stable A (Cl‐Fe‐F‐Cl‐Fe‐F) stack possesses concurrent and spontaneous BMS nature and valley polarization with perpendicular magnetic anisotropy (PMA), while B (Cl‐Fe‐F‐F‐Fe‐Cl) and C (F‐Fe‐Cl‐Cl‐Fe‐F) stacks exhibit AFM semiconductor characters without valley polarization. Electric‐field achieves a transition of BMS and AFM semiconductor. Large ferrovalley (≈108 meV) exists and is mainly contributed by Fe‐dxy and dx2−y2${{d}_{{{x}^2} - {{y}^2}}}$ orbitals. With the out‐of‐plane to in‐plane to out‐of‐plane transition of the easy axis, anomalous valley Hall effect (AVHE) can be manipulated to presence and disappearance by perpendicular electric‐field, indicating the valley switch effect (VSE). The coexisting BMS feature, PMA, AVHE and VSE make Janus FeClF bilayer a promising candidate for multifunctional valleytronic and spintronic applications, favoring broad explorations for the low‐dimensional Janus family. [ABSTRACT FROM AUTHOR]

Context: The nature of double intermolecular proton transfer was studied with the ELF topological approach in two model dimers (the formic acid homodimer and the 1,2,3-triazole–guanidine heterodimer) under an oriented external electric field. It has been shown that each of the two dimers can have either a one-step (one transition state structure) or two-step (two transition state structures) reaction path, depending on the intensity and orientation of the external electric field. The presence of a singularly broad shoulder (plateau in the case of homodimer and plateau-like for heterodimer) around the formal transition state structure results from the strong asynchronicity of the reaction. A careful ELF topological analysis of the nature of protons, hydride (localized) or roaming (delocalized) proton, along the reaction path allowed us to unambiguously classify the one-step mechanisms governing the double-proton transfer reactions into three distinct classes: (1) concerted-synchronous, when two events (roaming proton regions) completely overlap, (2) concerted-asynchronous, when two events (roaming proton regions) partially overlap, and (3) two-stage one-step non-concerted, when two roaming proton regions are separated by a "hidden intermediate region". All the structures belonging to this separatrix region are of the zwitterion form. Methods: Geometry optimization of the stationary points on the potential energy surface was performed using density functional theory—wB97XD functional—in combination with the 6–311+ +G(2d, 2p) basis set for all the atoms. All first-principles calculations were performed using the Gaussian 09 quantum chemical packages. We also used the electron localization function (ELF) to reveal the nature of the proton along the reaction path: a bound proton (hydride) becomes a roaming proton (carrying a tiny negative charge ≈ 0.3 e) exchanging with two adjacent atoms via two attractors (topological critical points with (3, − 3) signature). The ELF analyses were performed using the TopMod package. [ABSTRACT FROM AUTHOR]

This paper investigates the hydrothermal behavior of leaky dielectric and perfect dielectric droplets impacting a superheated wall within a specific range of Weber numbers (We≤30) $(We\le 30)$ under an electric field. Through this investigation, we aim to provide a more comprehensive understanding of the dynamics involved in droplet‐superheated surface interactions under electric fields, which can be useful in various applications, such as the design of cooling systems and combustion chambers. The study utilizes the level‐set and ghost fluid techniques to capture the interface accurately. Under an electric field, different behaviors are observed during the impact process, depending on the electrical properties of the droplet. A perfect dielectric droplet experiences a reduction in spreading extent and an increase in contact time. However, no remarkable enhancement in total heat removal occurs in this case. For the leaky dielectric droplet exhibiting prolate deformation at the stationary state, increasing the electric field magnitude results in a slight decrease in the droplet spreading extent, while the droplet contact time and total heat removal from the surface increase. At an electric capillary number of 1.55E − 2 and a Weber number of 25, the enhancement in the contact time and total heat removal is about 43% and 15%, respectively. For the leaky dielectric droplet with oblate deformation at the stationary state, the spreading extent and total heat removal increase, with negligible changes in contact time. At the above‐mentioned electric capillary and Weber numbers, the enhancement in the spreading extent and total heat removal is about 7.5% and 15%, respectively. [ABSTRACT FROM AUTHOR]

The efficient separation of water-in-oil emulsions plays an important role in many industrial fields. However, the demulsification performance using a single method is limited. In recent years, a novel deep purification method combining direct current electric field and medium coalescence has been proposed. To better understand the mechanism of this process, this work investigated the behavior of water droplets at different conditions. The results show that all injected water droplets initially migrate toward the charging side, while the opposite movement of some droplets is due to collision with the others or breakage from the original ones. The droplets migrated back and forth between electrodes through the polarize-discharge process. However, owing to the heterogeneous electric field near the charging side, some large-size droplets rebounded at a certain distance away from the charging electrode, leading to a counterflow of W/O emulsion during electrostatic coalescence. Moreover, the higher voltage leads to the faster coalescence of dispersed droplets on the medium surface, and the wetted medium can redistribute the electric field. With the collision and the deposition of water droplets, different kinds of water areas were formed and kept a dynamic equilibrium on the medium surface. The subsequent water droplets deposited on the medium surface and then flowing away along these areas. The results proposed in this paper present an in-depth understanding of the mechanism of the electrocoalescence, the medium coalescence, and the combination of them, which provides useful insights for the design of demulsification device and the separation process of W/O emulsion. [ABSTRACT FROM AUTHOR]

In the approximation of the effective mass, the electric field effect on the optical properties of the elliptical quantum wire (EQW) was investigated. In an elliptic coordinate system, exact solutions of the Schrödinger equation for an electron in an EQW with hard walls are obtained. The electron energy spectrum consists of even and odd energies states, whose wave functions are expressed through even and odd Mathieu functions of the first kind. Using these solutions, an orthonormal basis was constructed. The influence of the electric field perpendicular to the quantum wire and parallel to the ellipse's major axis on the energies and oscillator strength of quantum electron transitions was calculated using the matrix method. It is shown that the ellipticity of the quantum wire leads to the removal of the degeneracy of the energy spectrum of quasiparticles since the energies of even and odd electronic states depend differently on the ratio of the EQW semi-axes. The electron's ground state is the even state, which is nondegenerate because there is no corresponding odd state. The electric field has a greater effect on energy states with a lower value of the magnetic quantum number. As the electric field strength increases, the energies of even and odd states shift to the region of lower energies. [ABSTRACT FROM AUTHOR]

The electro-hydro-dynamic-atomization (EHDA) is a well-established technology with numerous micro/nanoparticle fabrication applications. However, a consistent method for explaining the physics behind the process has yet to be established. The present study aims to report a comprehensive non-dimensional analysis to develop a correlation between different process parameters. The dimensionless numbers derived from Buckingham's pi theorem match well with those derived from the Navier–Stokes equation, establishing the forces involved in EHDA. Flow instability modes during the EHDA process are experimentally visualized using the flow visualization technique and characterized using a microscope. The instability modes are described using derived non-dimension numbers, and results closely align with Ganan-Calvo's findings. Derived scaling for the current is in good agreement with Ganan-Calvo (1997), which complies with the condition if δμ × (Q/Qo)1/3 > > 1, then I/Io = 11 × (Q/Qo)1/4 -5. Moreover, the ratio of ln (Ehd)/ ln (Md) in cone jet mode is found to be ≈2, irrespective of fluids. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)

The addition of physical field enhancement measures to improve the purification effect of vertical flow artificial wetlands has gradually become popular. In this study, a vertical flow artificial wetland system reinforced by electric and magnetic fields was constructed. These fields were first optimized using finite element 3D simulation software to obtain the optimal electric and magnetic field parameters. Then, the pollutant removal effects and changes in microbial community structure were comparatively analyzed. The optimal electromagnetic field parameters (applied voltage of 15 V and applied magnetic field of 20 mT) resulted in significantly enhanced removal rates of chemical oxygen demand (COD), nitrate nitrogen (NH4+-N), total phosphorus (TP), and orthophosphorus (PO43−-P) in wastewater, with rates of 74.47%, 45.44%, 89.85%, and 90.04%, respectively. These rates were notably higher than those observed in the vertical flow artificial wetland system. The microbial community structure analysis revealed that the vertical flow constructed wetland with enhanced electric and magnetic fields exhibited (EM-VFCW) a more diverse and complex microbial community structure. Notably, the abundance of bacteria capable of removing NH4+-N and COD, including Aspergillus, Fusarium, and Actinobacteria, was significantly elevated. [ABSTRACT FROM AUTHOR]

In this paper, a novel 3300 V/40 A 4H-SiC junction barrier Schottky diode (JBS) with a multi-step separated trench (MST) structure is proposed and thoroughly investigated using TCAD simulations. The results show that the introduction of MST expands the Schottky contact area, resulting in a decrease in the forward voltage drop. Furthermore, the combination of the deep P+ shielded region and the central P+ region effectively reduces the leakage current, leading to a 43.7% increase in the blocking voltage compared to conventional 4H-SiC JBS. The effects of the step depth (ds) and the width of the central P+ region (wm) on the device performance are analyzed in depth. In addition, a multi-step trenched linearly graded field-limiting rings (MTLG-FLR) termination ensures a more uniform electric field distribution, and the terminal protection efficiency reaches up to 90%, which further enhances the reliability of the terminal structure. [ABSTRACT FROM AUTHOR]

The regime of horizontal subcooled film boiling is characterized by the formation of a thin layer of vapor covering the surface of a flat horizontal heater. Based on the equations of motion of a viscous incompressible fluid and the equation of heat transfer, the stability of such a vapor film is investigated. The influence of the modulation of the gravity field caused by vertical vibrations of the heater of finite frequency, as well as a constant electric field applied normal to the surface of the heater, is taken into account. It is shown that in the case of a thick vapor film, the phase transition has a little effect on the thresholds for the occurrence of parametric instability in the system and its transformation into the most dangerous one. At the same time, the electric field contributes to an increase in these thresholds. It was found that the effect of vibrations on the stabilization of non-parametric instability in the system is possible only in a narrow region of the parameter space where long-wave damped disturbances exist and consists of reducing the critical heat flux of stabilization. A vapor film stabilized in this way can be destroyed due to the development of parametric instability. In contrast to the case of a thick vapor layer, the threshold for the onset of parametric instability for thin films largely depends on the value of subcooling in the system. In addition, this threshold decreases with increasing electric field strength. For a vapor film ten microns thick, the instability threshold can be reduced by a factor of three or more by applying an electric field of about three million volts per meter. [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]

In this research, tantalum nanoparticles were prepared by the laser ablation method and the effect of an electric field on their structural properties was investigated. The optical absorption spectra were studied to comprehend the optical properties of nanoparticles. Size and morphology of nanoparticles are illustrated by TEM images. The average size of tantalum nanoparticles is 19 and 45 nm for synthesized samples without and with electric fields, respectively. By applying an electric field, the morphology of nanoparticles changed from spherical to tangled shapes. XRD analysis showed the crystalline structure of nanoparticles. The investigation of bending and stretching of molecular functional groups and the measurement of the hydrodynamic radius were done by FTIR, RAMAN and DLS analyses, respectively. FTIR, RAMAN, XRD and DLS analyses confirm the structure. EDX spectra confirmed the existence of ingredients. The stability of colloidal is indicated by zeta potential analysis. Photoluminescence spectra reveal nanoparticle properties. As the electric field increases, the size of nanoparticles increased, morphology changes from spherical, and oxidation increases. [ABSTRACT FROM AUTHOR]

Electrochemical reactivity is known to be dictated by the structure and composition of the electrocatalyst-electrolyte interface. Here, we show that optically generated electric fields at this interface can influence electrochemical reactivity insofar as to completely switch reaction selectivity. We study an electrocatalyst composed of gold-copper alloy nanoparticles known to be active toward the reduction of CO2 to CO. However, under the action of highly localized electric fields generated by plasmonic excitation of the gold-copper alloy nanoparticles, water splitting becomes favored at the expense of CO2 reduction. Real-time time-dependent density functional tight binding calculations indicate that optically generated electric fields promote transient-hole-transfer-driven dissociation of the O-H bond of water preferentially over transient-electron-driven dissociation of the C-O bond of CO2. These results highlight the potential of optically generated electric fields for modulating pathways, switching reactivity on/off, and even directing outcomes. [ABSTRACT FROM AUTHOR]

The corona-generated electromagnetic field environment under and nearer to the extra high dc potential conductors generates an ill health environment which causes serious electrical threats to living organisms present in the conductor corridor. The ionized electromagnetic field environment is characterizing with ionized ionic current flow and enhanced electric field perturbation at ground levels. The primary factors which affect the safe and economical design dimensions of high potential dc conductors are conductor diameter, altitude, applied potential and atmospheric parameters such as temperature, humidity, pressure, and aerosol pollution, etc. This remains a challenging task to design the HVDC transmission system at extended potential levels, as HVDC system employed for a large amount of power transfer barrier in the electrical system to meet inevitable power thrust. To obtain a safe and economical design configuration, multiple experimental design measurements are essential at various climatic seasons which incorporates the tedious process and significant economical expenditure. To obtain the safe and cost-effective design dimension configuration, computational-based numerical analysis with final experimental validation offers substantial support. Using various computational methodologies, many researchers have attempted to guide the critical line design proportions to establish a safe and economical electrical environment beneath the lines at ground levels. All these computational techniques are emphasizing the algorithm iterative-based complex solutions claim the lack of computational accuracy. Hence, this work aims to provide a unique computational technique to analyse the ionised electromagnetic field environment of a unipolar UHV dc transmission system using modelling of the physics of the corona discharge procedure in the active high electrostatic field zone. Modelling of the corona discharge includes the estimation of the amount of new ionized ions generated in the ionization region dynamically claims complex less equations offer a unique solution. To validate the accuracy of the proposed computational technique, multiple outdoor experimental measurements are carried out at HV/EHV/UHV potential applications and discussed. Also, the computed results are compared with the experimental findings, from the comparison outstanding computational accuracy was marked. [ABSTRACT FROM AUTHOR]

We report on the evidenced giant vertical magnetization shift in Ag/NiO/Fe/FTO bilayers when electric field Ez (electric field applied in z direction) and magnetic field Hz (magnetic field applied in z direction) are parallel to each other. Calculated vertical magnetization shift (ME) is determined to be 1168 emu/cc (259%) for applied voltage of +1.5 V, while it is −1142 emu/cc (252%) for –1.5 V respectively. Such a huge change is attributed to the pinning of spins at the interface through resistive switching phenomena that is governed through oxygen ion migration at the interface. The quantitative correlation between interfacial anisotropy energy and the applied electric field is established. Determined coefficient pertinent to electric-field-control of magnetic anisotropy is found to be 1.19 × 10−8 erg/V cm when Ez and Hz are parallel to each other. A reversible and reproducible magnetization switching is demonstrated by applying +1.5 V and −1.5 V repeatedly, which demonstrates robustness of the magnetization switching in fabricated device. Indeed, intermediate magnetization states are availed through voltage, which may be of great interest for the multi-bit data storage and energy efficient spintronic devices. [ABSTRACT FROM AUTHOR]

Electrolyte cations have been demonstrated to effectively enhance the rate and selectivity of the electrochemical CO2 reduction reaction (CO2RR), yet their implementation in electrolyte‐free membrane electrode assembly (MEA) electrolyzer presents significant challenges. Herein, an anchored cation strategy that immobilizes Cs+ on carbon vacancies was designed and innovatively implemented in MEA electrolyzer, enabling highly efficient CO2 electroreduction over commercial silver catalyst. Our approach achieves a CO partial current density of approximately 500 mA cm−2 in the MEA electrolyzer, three‐fold enhancement compared to pure Ag. In situ Raman and theoretical analyses, combined with machine learning potentials, reveal anchored Cs induces an electric field that significantly promotes the adsorption of *CO2− intermediates through performing muti‐point energy calculations on each structure. Furthermore, reduced adsorption of *OH intermediates effectively hampers competing hydrogen evolution reaction, as clarified by disk electrode experiments and density functional theory studies. Additionally, coupling our system with commercial polysilicon solar cells yields a notable solar‐to‐CO energy conversion efficiency of 8.3 %. This study opens a new avenue for developing effective cation‐promoting strategy in MEA reactors for efficient CO2RR. [ABSTRACT FROM AUTHOR]

When an airplane flies in an electric field under a thundercloud, electric fields at the edges and projected portions of the airplane are enhanced and leaders emanate from there. When a positive leader emanating upward from the airplane connects with a downward negative leader from the bottom of an ordinary thundercloud and a negative leader emanating downward from the airplane connects with an upward positive leader from the ground, a large lightning current flows along the channel bridged between the thundercloud and the ground through the airplane. Recently, a method to reduce the risk of lightning strikes to airplanes has been proposed. It controls the charge on the surface of an airplane to suppress the electric field at edges and projected portions of the airplane. In this paper, an airplane under a thundercloud is represented with a vertical conducting bar or a horizontal conducting bar with a small projected portion, which is placed between impulse‐high‐voltage‐applied two flat electrodes, and it is analyzed using the finite‐difference time‐domain (FDTD) method. Corona and leader discharges emanating from edges and projected portions of an airplane model are considered with their engineering representations: 40‐μS/m and 0.02 S/m conducting regions for corona and leader discharges, respectively. The airplane model is not pre‐charged or pre‐charged negatively. It follows from the FDTD‐computed results that pre‐charging an airplane model with a relevant amount of negative charge can avoid discharges from and to the airplane model. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Nonuniform cementation challenges may arise when employing microbially induced calcium carbonate precipitation (MICP) technology to treat problematic soils. Electrokinetic methods exhibit the potential to regulate the MICP process by driving negatively charged urease-producing bacteria and promoting the migration of reactant ions. However, the current understanding of bacterial behavior and the characteristics of CaCO3 precipitates under the influence of direct current (DC) electric fields remains unclear. In this study, we designed and fabricated microfluidic chips to simulate sandy soil matrices. By monitoring the real-time MICP reaction process in the microfluidic porous medium with and without a DC electric field through an optical microscope, we analyzed the impact of the electric field on the behavior of bacteria at different locations (i.e., attached and suspended bacteria) and on the morphology and distribution of CaCO3 crystals. Results show that initially injected bacteria adhered to the inner pore surfaces due to interfacial cohesion, whereas subsequently injected bacteria were predominantly suspended in the pore solution and driven toward the anode by the electric field, where they aggregated. Furthermore, the majority of Ca2+ precipitated near the cathode, resulting in larger-sized crystals, and a smaller quantity of Ca2+ precipitated at the anode, generating smaller-sized crystal particles. This observation highlights the crucial role of Ca2+ movement in determining the distribution of CaCO3. Under the influence of a DC electric field, the final precipitated CaCO3 crystals exhibit nonuniform sizes, with an overall smaller average size and more complex crystal morphologies. Our results provide the underlying insights to guide the regulation of the MICP process through applied electric fields. [ABSTRACT FROM AUTHOR]

The study presents a novel Silicon on Insulator (SOI) Metal–Semiconductor Field-Effect Transistor (MESFET) with an Aluminum Nitride (AlN) layer under the drain electrode, aiming to enhance the breakdown voltage and overall performance. AlN, known for its large breakdown field and bandgap, is utilized to modify the electric field distribution, thereby reducing parasitic capacitances (Cgs and Cgd) and improving frequency specifications. The AlN layer extends from the drain to the gate side, altering the electric field and depletion region in the gate area near the drain, resulting in a higher breakdown voltage. Simulation results reveal that the proposed AlN-SOI MESFET structure outperforms the conventional structure. Breakdown voltage increases from 22 to 47 V, attributed to the AlN layer's effect on electric field distribution. The study also analyzes parameters such as output power density, drain current, heating effect, carrier concentration, potential distribution, and parasitic capacitances. The AlN-SOI MESFET exhibits improved characteristics, including reduced self-heating, lower parasitic capacitances, higher transducer gain, and superior performance compared to existing structures. The proposed device demonstrates the potential for high-frequency and high-voltage applications, making it a promising choice for electronic applications. The fabrication process and ethical considerations are also discussed. [ABSTRACT FROM AUTHOR]

In this article, von Kárman MHD viscoelastic fluid flow with second-grade model through a heated permeable disk on electric field is examined thoroughly. The effects of viscous dissipation and elasticity on fluid motion around the disk, temperature and space-dependent heat source/sink are also examined. Governing partial differential equations are transmitted into ordinary differential equations with similarity functions. Later, nonlinear system of ordinary differential equations was solved with the help of Galerkin finite element method. Accuracy and validity of the method were noticed by comparing our results with the previous literature. Simulations are performed in order to capture the dynamics of the physical situations against the variation of the pertinent parameters. Nature of heat flux and stresses of the physical parameters are discussed. Physical influence of heat flux, heat transfer is exhibited graphically at the surface of disk and increases when the values of Prandtl number are increased, whereas there is a decreasing trend in the rate of heat transfer when the value of Eckert number is increased. [ABSTRACT FROM AUTHOR]

This current study focuses on predicting the electronic and magnetic behaviors of WCl3 monolayer when subjected to an external electric field. Unlike CrI3, the WCl3 monolayer displays a preference for an antiferromagnetic (AFM) ground state with an in-plane easy axis. This AFM state remains consistent across the entire spectrum (0–1 V/Å) of the external electric field. The indirect electronic band gap of the WCl3 monolayer is predicted to be about 2.16 eV. Through our analysis, we've identified that the dominance of the valence band maximum and the conduction band minimum stems mainly from the d x 2 - y 2 orbital (52% contribution) and the d z 2 orbital (97% contribution) respectively, attributed to the W element. The majority of electronic transitions related to the band gap arise due to these specific orbitals. Furthermore, the application of an external electric field can adjust the band gap to zero, prompting a transition from semiconductor to metal at an electric field intensity of E = 0.9 V/Å. Using mean field theory, we estimate the Neel temperature (TN) of the AFM system to be approximately 356 K, a notably high value surpassing room temperature. Moreover, the application of an electric field demonstrates the potential to further elevate the Neel temperature, crucial for the functionality of high-temperature spintronic devices. Our comprehensive examination also delves into the magnetic anisotropy of the WCl3 monolayer. The analysis of magnetic anisotropy energy (MAE) indicates that, contrary to the CrI3 monolayer, the transition metal W significantly contributes to the system's MAE, which is predicted to be − 3.44 meV / W . The magnetic easy axis aligns along the x direction (in-plane). [ABSTRACT FROM AUTHOR]

This study investigated the latitudinal variations of post‐sunset enhancements in the ionospheric electron density during the geomagnetic quiet period in May 2021 with a combination of high‐precision ionospheric parameters obtained from four ionosondes, Beidou geostationary satellite (BD‐GEO) receiver network and Sanya incoherent scatter radar (SYISR). We identified four categories of post‐sunset enhancement phenomena (Types 1–4), each with unique spatial and temporal evolutions, yet uniformly accompanied by a decrease in hmF2. Measurements of plasma drift vector velocities from SYISR and hmF2 gradients across various latitudes provided pivotal insights, confirming that the ionospheric post‐sunset enhancements can result from downward plasma motion due to westward electric field, downward field‐aligned drift, or a combination of both. For Type 1, dominated by field‐aligned drift, plasma density enhancements not only intensify at low latitudes but may also extend to mid‐latitudes, exhibiting a distinct temporal delay with increasing latitude. In contrast, Type 4, primarily driven by the westward electric field, is characterized by modest increases in plasma density confined to localized low‐latitude regions, with no observable latitudinal time delay in the peak of enhancements. Types 2 and 3, which are subject to the combined influence of the westward electric field and field‐aligned drift, exhibit plasma density increases at certain low‐latitude areas, with Type 2 presenting a delayed pattern and Type 3 showing none with rising latitude. Meanwhile, neutral winds can partially account for the observed post‐sunset enhancement from low to middle latitudes. These findings offer new insights into the factors influencing ionospheric behavior after sunset. Key Points: Four types of distinctive latitudinal variations of post‐sunset enhancements were identified with multiple data sets during the quiet periodAccompanying the increase in the electron density at sunset, the decrease in hmF2 is favorable for the formation of post‐sunset enhancementDownward field‐aligned drift and westward electric field govern the spatial scale of post‐sunset enhancements at low and middle latitudes [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering (China) / Huaxue Gongcheng is the property of Hualu Engineering Science & Technology Co Ltd. 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.)

Alzheimer’s disease (AD) is a prevalent neurodegenerative disorder, impacting millions of individuals worldwide. Among its defining characteristics is the accumulation of senile plaques within the brain’s gray matter, formed through the self-assembly of misfolded proteins contributing to the progressive symptoms of AD. This study investigates a polymorphic Aβ fibril under static and oscillating electric fields using molecular dynamics simulation. Specifically, we utilized a polymorphic fibrillar complex composed of two intertwined pentamer-strands of the Aβ1–40 peptide with the Osaka mutation (E22Δ), known for its toxicity and stable structure. Our findings demonstrate that a 0.3 and 0.4 V/nm electric field combined with a 0.20 GHz frequency effectively disrupts the polymorphic conformation of Aβ fibrils. Furthermore, we elucidate the molecular mechanisms underlying this disruption, providing insights into the potential therapeutic use of oscillating electric fields for AD. This research offers valuable insights into novel therapeutic approaches for combating AD pathology. [ABSTRACT FROM AUTHOR]

The atmospheric gravity waves (AGWs) generated by severe typhoons can facilitate the transfer of energy from the troposphere to the ionosphere, resulting in medium-scale traveling ionospheric disturbances (MSTIDs). However, the complex three-dimensional nature of MSTIDs over oceanic regions presents challenges for detection using ground-based Global Navigation Satellite System (GNSS) networks. This study employs a hybrid approach combining space-based and ground-based techniques to investigate the spatiotemporal characteristics of ionospheric perturbations during Typhoon Doksuri. Plane maps depict significant plasma fluctuations extending outward from the typhoon's gale wind zone on 24 July, reaching distances of up to 1800 km from the typhoon's center, while space weather conditions remained relatively calm. These ionospheric perturbations propagated at velocities between 173 m/s and 337 m/s, consistent with AGW features and associated propagation speeds. Vertical mapping reveals that energy originating from Typhoon Doksuri propagated upward through a 500 km layer, resulting in substantial enhancements of plasma density and temperature in the topside ionosphere. Notably, the topside horizontal density gradient was 1.5 to 2 times greater than that observed in the bottom-side ionosphere. Both modeling and observational data convincingly demonstrate that the weak background winds favored the generation of AGWs associated with Typhoon Doksuri, influencing the development of distinct MSTIDs. [ABSTRACT FROM AUTHOR]

Effects of eccentricity and horizontal electric field (EH) on the binary‐collision outcomes of water drops are examined using numerically calculated collision characteristics from previous studies and results of simulation experiment conducted by the authors. For a fixed collision kinetic energy (CKE), filament breakups can occur at all values of eccentricity but events of coalescence decrease, and that of sheet breakup increase with increasing eccentricity in absence of EH. However, as EH increases to ∼300 kVm−1 it opposes the variability of the coalescence and sheet breakup events with eccentricity. When EH exceeds ∼300 kVm−1 the collision outcomes might be determined only by the CKE and EH. The calculated value of coalescence efficiency and total number of fragments after a binary collision decreases with an increase in EH. It is argued that an electric field can significantly modify drop size distribution in thunderclouds and needs to be considered for development of precipitation. Plain Language Summary: Growth of water drops in clouds is mostly governed by the drop size distribution in them. When two drops collide with each other, they can either coalesce to form a single larger drop, or disintegrate into many smaller drops, or bounce back. These different outcomes after their collisions are mostly determined by whether the collisions are centric where the eccentricity of the collision is zero or grazing where the eccentricity is one or somewhere in between the two extremes. The present study shows that if the collisions occur in presence of a horizontal electric field, it opposes the effect of eccentricity on the outcomes of the collisions. In this study, simultaneous effects of eccentricity and horizontal electric field are examined from numerically calculated collision characteristics from previous studies and utilizing the results of a simulation experiment recently conducted by the authors. Simultaneous effects of eccentricity and electric field on coalescence efficiency and total and spectral size distribution of fragments generated after the collision have also been evaluated. The results suggest that the electric field can significantly modify drop size distribution in thunderclouds and need to be considered for the development of precipitation. Key Points: Horizontal electric field opposes the variability of coalescence/sheet breakup of water drops with eccentricity in binary collisionsNumber of fragments close to small (large) parent drop size decreases (increases) after collisions in the higher horizontal electric fieldBinary collisions in horizontal electric fields can substantially modify drop size distribution in thunderclouds [ABSTRACT FROM AUTHOR]

In this paper, we investigated the luminescence and kinetic properties of 1.1-nm-thick colloidal CdSe nanoplatelets rolled up into scrolls in an external electric field in the range of 0–150kV/cm. Luminescence spectroscopy revealed that placing CdSe nanoscrolls in an external electric field leads to quenching of the intensity of luminescence bands with an increasing electric field, whereas time-correlated single photon counting measurements demonstrate the acceleration of the relaxation processes of electronic excitation. These effects are due to a reduction in the overlap integral between the electron and hole wavefunctions which is the reason for the emergent field-induced luminescence quenching. [ABSTRACT FROM AUTHOR]

A model of a conducting cylinder with a radial temperature gradient which creates an electric field that increases with time in the surrounding vacuum is examined. The conditions under which this model functions are pointed out. An electric field is also generated when a magnetic field exists along the axis of the cylinder. This article discusses the interactions of the thermal flux, magnetic field, and charge distribution. Four models are considered with different conditions for the supply of electrons from a central source and the possibility either of capturing electrons inside the cylinder or their freely leaving it through the outer boundary. [ABSTRACT FROM AUTHOR]

The present study examines the electronic and optical properties of Rosen-Morse quantum wells, which exhibit hyperbolic and exponential potential profiles, subjected to intense laser fields and electric fields. Calculations are performed within the framework of the effective mass and parabolic band approximations. To determine the eigenvalues of electrons confined in these potentials, the diagonalization method was employed, utilizing orthonormal base functions that are solutions of an infinite square quantum well. To calculate the total absorption coefficient, including linear and nonlinear terms for transitions between the lowest two energy levels, a combination of the standard density matrix formalism and the perturbation expansion method was employed. Our results indicate that intense laser field is a valuable tool for controlling the confinement potential of low-dimensional systems, enabling the appropriate tuning of these systems. While the electric field applied only to symmetrical structures breaks the symmetry and causes the peaks in the absorption spectrum to shift to red, a blue shift of the absorption peaks was achieved with the combined effect of the selected geometric shapes of the quantum wells and the electric field. Therefore, it is hoped that the obtained results will provide important improvements in device applications with a suitable choice of both fields and structure parameters. [ABSTRACT FROM AUTHOR]

The unique electromagnetic properties of rare earth elements (REEs) have led to rapid technological advances, creating a sharp increase in demand for these materials. The inherent challenges of separating REEs and the significant drawbacks of existing processes have driven the development of a new method known as field-effect separation (FES). This technology leverages electrical and magnetic fields to achieve separation by exploiting the differences in magnetic moments or effective charges of REEs in solution. Experiments on REEs were conducted using a microchannel based separation device, which confines fluid flow to facilitate separation within a field, with metal cations in solution being transported based on their respective electrostatic or magnetic properties. The results demonstrate that separation based on effective charge or paramagnetic properties is achievable. The confinement of fluid flow to microchannels allowed advective and osmotic forces to be suppressed sufficiently such that a reasonable separation of ions was achieved, though the impact of these forces were not completely removed. This innovative approach promises to improve the efficiency and effectiveness of REE separation, addressing both the growing demand and the limitations of current methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the possibility of separating free bran from bulgur using the triboelectric property of a flat PVC surface. The findings demonstrate that bran, which has an adverse impact on the physical appearance and quality of bulgur, can be effectively separated. It was established that the study offers a solution to the issue of bran. The use of a flat PVC surface, which can be defined as a flat inclined channel, represents a new technological development for bulgur production technology. The dimensions of the device were designed to be 4, 5 and 6 cm in width, 20, 40 and 60 cm in length, and with angles of 30, 35 and 40 degrees, respectively. A series of plates was fixed at the final point of the PVC surface in order to establish an electric field. To generate the electric field, one of the plates was subjected to a positive charge, while the other was treated with a negative charge. A variety of distances were observed between the plates, contingent upon the width of the tunnel. The flat PVC system proved to be an effective means of achieving the desired outcome. Consequently, a fine bulgur-bran mixture with an initial bran content of 5 g per 1000 g of bulgur was conducted through the system at a flow rate of 0.89 g/s. This resulted in a significant reduction in bran content from 5 g to approximately 2 g (60% reduction). [ABSTRACT FROM AUTHOR]

One of the inherent limitations associated with laser-induced breakdown spectroscopy (LIBS) in the identification of elements lies in the strength of the emission signals. Several approaches exist to enhance the emission capacity of LIBS. In this particular investigation, our focus was on amplifying the signal intensity of LIBS through the utilization of two techniques. These techniques include the application of a low-power electric field within the zone where plasma is formed, in conjunction with the utilization of nanoparticles on the surface of the sample. Specifically, our analysis involved the examination of samples consisting of metallic Zn powder as the matrix element, with the incorporation of small quantities of Ca in the form of CaCO3. The combination of these two methods resulted in unprecedented outcomes, demonstrating a 3.5-fold increase in samples containing 0.05% w/w of CaCO3 when subjected to an electric field of 60 V/cm, while bearing nanoparticles on their surface. [ABSTRACT FROM AUTHOR]

How to induce magnetism for two-dimensional materials has always been a focus of research in nanomaterials science. In this work, employing density functional theory, we investigated the structural stability and electronic-magnetic properties of antimonene-phosphorene (SbP) nanoribbons doped with B, C, N, and O atoms. Additionally, we investigated the effects of vacancy defects along with impurity atoms doping on antimonene-phosphorene nanoribbons. Our analysis revealed that all doped and defected structures displayed robust structural stability, as evidenced by negative binding and formation energies. It was found that the substitution of impurity atoms in either P or Sb positions of the SbP nanoribbon leads to different behaviors, and only the SbP nanoribbons doped with C atom in P position and doped with O atom in Sb position show magnetic properties. Moreover, we observed that the magnetic properties of vacancy structures doped with impurity atoms varied based on the number of doping atoms in P or Sb positions. For instance, spin polarization behavior can be realized in P-vacancy nanoribbons doped with one and two N atoms, and the magnetic moment variations in Sb-vacancy nanoribbon doped with N atoms are nearly three times greater than those of the P-vacancy nanoribbon. Furthermore, the effects of the transverse electric field have also been calculated, and we found that applying an electric field to the system can reduce the band gap and modulate the magnetic moment. Intriguingly, we observed negative differential resistance behavior and an 80% spin filtering effect in antimonene-phosphorene nanoribbons with a phosphorus vacancy. Overall, these findings offer new insights into designing next-generation nano spintronic devices within antimonene-phosphorene nanoribbons. [ABSTRACT FROM AUTHOR]

Due to the unlimited usage and involvement of nanoparticles, researchers got much interest in their study. This research discusses the utilization of a hybrid nanofluid model mixed in water-based liquid in a rotating disk. The flow is considered with the involvement of Hall and ion slip effects in a rotating disk. Thermal transport is discussed by engaging quadratic thermal radiation phenomenon along with Joule heating. The boundary layer equations are generated in the form of coupled PDEs and are converted into a set of ODEs by engaging similarity variables. The derived converted ODEs are highly nonlinear and have been solved numerically via the finite element method. The involvement of numerous emerging parameters against velocity, temperature and concentration is plotted and tabulated and their insight physics is discussed in detail. The obtained results confirm the reliability of finite element scheme. [ABSTRACT FROM AUTHOR]

Moisture is the critical factor affecting transformer oil-paper insulation's aging life and electrical strength. Currently, there is no sensing technology that directly monitors the moisture content of paper in operating transformers, and it still relies on the moisture equilibrium curves of oil-paper (MEC) to achieve indirect calculation. However, the MEC only considers the temperature effect, and the electric field effect is less studied. Therefore, research on the effect of direct current electric fields on the MEC at 80 °C is carried out in this work. The results show that the electric field has an inhibitory effect on moisture migration, and as the electric field strength increases, the moisture in the oil and paper will rise significantly. Compared with the MEC, the experimental result of 0 kV/mm is basically consistent, and after applying the voltage, the moisture in the paper corresponding to the same moisture in the oil increased by 5.86%, 18.61%, and 32.92% at 5 kV/mm, 15 kV/mm and 25 kV/mm on average. Moreover, the accuracy of the experimental results is further verified by macroscopic force analysis and microscopic molecular simulation calculations. This work provides a reference for correcting the MEC under the action of multi-physical fields. [ABSTRACT FROM AUTHOR]

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In the present work, we explored the impact of doping concentration and applied electric field on both linear and nonlinear optical properties based upon the intersubband transitions of CdSe/MgSe single quantum wells (QWs) in the framework of the effective mass approximation (EMA) using the compact density matrix approach. The energy levels and their relative wave functions were obtained by solving the coupled Schrödinger–Poisson equations by the finite difference method (FDM) under the envelope wave function approximation. The third-order nonlinear optical susceptibility, the refractive index changes (RIC), and the absorption coefficients (AC) were investigated as a function of doping concentration. The numerical results revealed that an increase in the doping concentration ND results in a blue shift of the peak position of the linear and nonlinear optical properties, with a substantial enhancement of their magnitudes. The same behavior related to the third-order nonlinear susceptibility was noted when the considered structure was subjected to an external electric field. [ABSTRACT FROM AUTHOR]

Research presented in this paper analyzes the accuracy and applicability of analytical expressions to describe the electric field of a high-voltage glass insulator. The metal cap and the metal pin of the glass insulator are represented by coaxial cylindrical electrodes. The insulating materials between them are modeled as coaxial hollow cylinders. Analytical expressions for the electric field in these insulating materials are derived. Using these expressions, the spatial distribution of the electric field in the insulating materials was determined. Suitable software, based on the finite element method (FEM), was used to determine the spatial distribution of the electric field in dielectrics in the same space. Both analyses were performed under quasi-static conditions, and the results of the analytical expressions were compared with the FEM results. Discrepancies between the results of the two mentioned analyses were observed. The reasons for the observed discrepancies and the applicability of the presented analytical expressions are commented on. [ABSTRACT FROM AUTHOR]

Plasma originating from the satellite Io forms a dense plasma region known as the Io plasma torus (IPT) in the Jovian inner magnetosphere. Slightly inside the Io‐orbit is a distinct structure called the "ribbon," where the plasma spreads along the magnetic field lines. The ribbon moved dawnward owing to the dawn‐to‐dusk electric field. Extreme ultraviolet (EUV) observations of the IPT showed that the electric field was enhanced under compressed conditions of the magnetosphere caused by solar wind. However, no reports have been published on the influence of solar wind on the radial position of the ribbon. Here, we show the correlation between the temporal variation in the ribbon's position and solar wind. We analyzed the visible ([SII] 6716, 6731 Å) IPT images observed by the Tohoku 60‐cm telescope (T60) and the EUV emissions observed by the Hisaki satellite. We found that the position of the ribbon shifted dawnward when the solar wind dynamic pressure was enhanced. The dawnward shift was more significant on the dawn side than on the dusk side, indicating that the change in the electric field was inhomogeneous. The simultaneous observations of T60 and the Hisaki satellite on 19–23 February 2016 indicated that the averaged intensity of the electric field derived from T60 was 3.9 ± 0.9 mV/m, consistent with that of 2.8 ± 1.2 mV/m derived from the Hisaki satellite. Our results demonstrate how solar wind affects the nonuniformity of the electric field in the inner magnetosphere. Key Points: The ribbon's position shifted dawnward when the solar wind dynamic pressure enhancedThe strength of the electric field derived from the ribbon's position was 3.9 ± 0.9 mV/mThe shift was more significant on the dawn side than on the dusk side, indicating that the change in the electric field was inhomogeneous [ABSTRACT FROM AUTHOR]

The current study aimed to create an electrostatic window screen to keep stable flies and houseflies out of cattle barns. The screen comprised three identical framed metal nets arranged in parallel at specific intervals. The central net was connected to a negative-voltage generator to impart a negative charge, while the other two nets were grounded and placed on either side of the charged net. This configuration generated a corona-discharging electric field between the nets. The electric field produced negative ions and ozone around the negatively charged net, deterring houseflies from entering. Additionally, the screen emitted sparks via arc discharge to repel stable flies that did not exhibit avoidance behavior. The spark irradiation was intense enough to swiftly propel flies backward upon entering the electric field, ultimately leading to their demise. In summary, the device functioned as a corona-discharging screen to repel houseflies and as an arc-discharging screen to eliminate stable flies through spark irradiation. This study provides an experimental foundation for the development of an innovative device to manage undesirable flies in cattle barns. [ABSTRACT FROM AUTHOR]

Abstract Cellular motility is essential for making and maintaining multicellular organisms throughout their lifespan. Migrating cells can move either individually or collectively by a crawling movement that links the cytoskeletal activity to the adhesion surface. In vitro stimulation by electric fields can be achieved by direct, capacitive or inductive coupled setups. We tested the effects of electrical stimulation provided by capacitive coupling on glioma cells, using a capacitive-coupled system powered by a potential difference of 35 V between two electrodes placed outside the culture dish. Numerical dosimetry identified two different fields: (i) in the order of 103 V/m at the level of the dielectric substrates, with almost uniform distribution; (ii) in the order of 10−1 V/m at the level of the culture medium, with spatial and material-dependent distribution. The scratch assay and the tracking of single-cell movement showed a boosted motility when crawling occurs on polystyrene surfaces, demonstrating the feasibility of this peculiar exposure system to generate forces capable of influencing cell behavior.

Abstract The presented work brings new knowledge in the field of spinning electrodes for AC‑electrospinning technology, which is used for producing nanofibrous structures using a solution of polyvinyl butyral. It presents new types of spinning weir‑electrodes and describes research on the influence of electrode design parameters on the stability of the spinning process and the productivity of nanofiber production. The multistage spinning electrode is presented in the ratio of stages one to five. Research is also focused on the effect of the parameters of the electric signal used as a source for the spinning electrode on spinning stability and productivity. Observed parameters were voltage level, frequency and shape such as sine wave, rectangle wave and modified sine wave. An analysis of the influence of the spinning conditions on the resulting nanofibrous structure was also performed by analyzing results gained by SEM; the defects were investigated mainly. The results of the research presented in the thesis open up new possibilities for follow-up research in the field of AC-electrospinning.

Abstract Alzheimer’s disease (AD) is a prevalent neurodegenerative disorder, impacting millions of individuals worldwide. Among its defining characteristics is the accumulation of senile plaques within the brain’s gray matter, formed through the self-assembly of misfolded proteins contributing to the progressive symptoms of AD. This study investigates a polymorphic Aβ fibril under static and oscillating electric fields using molecular dynamics simulation. Specifically, we utilized a polymorphic fibrillar complex composed of two intertwined pentamer-strands of the Aβ1–40 peptide with the Osaka mutation (E22Δ), known for its toxicity and stable structure. Our findings demonstrate that a 0.3 and 0.4 V/nm electric field combined with a 0.20 GHz frequency effectively disrupts the polymorphic conformation of Aβ fibrils. Furthermore, we elucidate the molecular mechanisms underlying this disruption, providing insights into the potential therapeutic use of oscillating electric fields for AD. This research offers valuable insights into novel therapeutic approaches for combating AD pathology.

The unique electromagnetic properties of rare earth elements (REEs) have led to rapid technological advances, creating a sharp increase in demand for these materials. The inherent challenges of separating REEs and the significant drawbacks of existing processes have driven the development of a new method known as field-effect separation (FES). This technology leverages electrical and magnetic fields to achieve separation by exploiting the differences in magnetic moments or effective charges of REEs in solution. Experiments on REEs were conducted using a microchannel based separation device, which confines fluid flow to facilitate separation within a field, with metal cations in solution being transported based on their respective electrostatic or magnetic properties. The results demonstrate that separation based on effective charge or paramagnetic properties is achievable. The confinement of fluid flow to microchannels allowed advective and osmotic forces to be suppressed sufficiently such that a reasonable separation of ions was achieved, though the impact of these forces were not completely removed. This innovative approach promises to improve the efficiency and effectiveness of REE separation, addressing both the growing demand and the limitations of current methods.

Dual electric field and defect engineering induced multi-channel electron transfer promoted the hydrogen production of CZMOZIS heterojunction. [Display omitted] • A high efficient CZMOZIS heterojunction was synthesized by hydrothermal method. • The H 2 evolution rate of CZMOZIS was 9.7 times than that of ZIS. • The enhanced IEF of the CZMOZIS composites provided a strong driving force for charge transfer. • Dual electric field and defect engineering promoted the hydrogen production of CZMOZIS heterojunction. Serious recombination of photogenerated carriers is the bottleneck problem of achieving high-performance photocatalytic reaction. A high efficient Cu2+-doped ZnMoO 4 /ZnIn 2 S 4 (CZMOZIS) heterojunction was synthesized by hydrothermal method. The CZMOZIS heterostructure achieved hydrogen production of 11637.5 µmol g−1 within 5 h, which was 9.7 times higher than that of pure ZnIn 2 S 4. Comprehensive characterization and theoretical calculation demonstrated that the CZMOZIS composites exhibited broad light absorption, an increased specific surface area and an optimized Gibbs free energy. The presence of oxygen vacancies in CZMOZIS composites was confirmed by X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy, revealing the formation of defect levels below the conduction band (CB) of ZnMoO 4. Kelvin probe force microscopy (KPFM) and Zeta potential demonstrated that the intrinsic electric field (IEF) of the CZMOZIS heterojunction was enhanced, which may be attributed to the generation of polarization electric field (PEF). The double electric field provided a robust driving force for the photogenerated carrier migration and separation. The electrons in the CB and defect levels of Cu2+-ZnMoO 4 could be coupled with the holes of ZnIn 2 S 4 , thereby forming a multi-channel electron transfer. This work provides a theoretical support for promoting charge transfer to improve photocatalytic performance by dual electric field and defect engineering. [ABSTRACT FROM AUTHOR]

Ba 1– x Sr x TiO 3 (BST) ceramics are promising dielectric materials. However, their fabrication is usually laborious, requiring long preparation stages and high temperatures, which are not favorable for tuning the grain size and dielectric properties. In this study, (Ba 1– x Sr x)TiO 3 (x = 0.1, 0.3, 0.5) ceramics were produced via reactive flash sintering (RFS) of a mixture of BaCO 3 , SrCO 3 and TiO 2 powders at 900 °C and relatively short times (15–90 s). The electric field (E-field) with a strength of 400 V/cm and the current densities of 25–75 mA mm−2 were applied during RFS. Once the Sr2+ content increased, the incubation time for the RFS decreased, suggesting that the addition of Sr2+ facilitated the RFS process. At the RFS time above 15 s, a single-phase Ba 0.6 Sr 0.4 TiO 3 perovskite structure was formed. When the time and the applied current density increased, both the densities and grain sizes within the ceramics increased. This increased the real part (ε ') of the complex permittivity compared to that of the conventionally sintered (CS) ceramic. Moreover, the enhancement of mass transport by E-field-induced oxygen vacancies was considered the predominant mechanism of RFS in the production of BST ceramics. [ABSTRACT FROM AUTHOR]

In this paper, two new silicon on insulator metal-semiconductor field effect transistor (SOI-MESFET) structures are presented. Two parallel layers of oxide and aluminium are added at the gate edge of these structures. Also, in the buried oxide part of the Aluminium Edge and Silicon-Well MESFET (AESW-MESFET) structure, a silicon well and two aluminium layers are added. Moreover, and to improve the DC and RF characteristics, as compared to the Conventional MESFET (C-MESFET) structure, a silicon well and a silicon layer are added in the box oxide section in the Silicon Edge and Silicon-Well MESFET (SESW-MESFET) structure. By these changes, the value of the breakdown voltage in the normal structure has increased from 15.8 V to 33.1 V and 30.9 V in the proposed AESW-MESFET and SESW-MESFET structures, respectively. In addition, the maximum output power has been associated with a significant increase of 4.44 and 5.24 times, respectively. Compared to the C-MESFET, the proposed structures reduce gate-source and gate-drain capacitors and significantly increases conductivity. The cut-off frequency values are increased from 19.3 GHz (the normal structure) to 37.3 GHz and 35 GHz (the proposed structures), and the maximum oscillation frequencies are increased from 80 GHz to 154 GHz and 102.3 GHz. Therefore, the results show that the proposed structures have good performance and the ability to work at high power and high frequency. [ABSTRACT FROM AUTHOR]