Search Results (1,878)

Weak alternating electric fields are widely used in neuromodulation techniques such as transcranial alternating current stimulation (tACS), yet the precise biophysical mechanisms underlying neuronal responses remain incompletely understood. Current computational models often neglect the electrical properties of the extracellular microenvironment, limiting their predictive accuracy. Motivated by experimentally observed frequency-dependent modulation of neuronal activity, we developed a two-compartment model of hippocampal CA3 pyramidal neurons in which extracellular resistance is explicitly parameterized and systematically examined as a key factor influencing neuronal response properties under external electric fields. Within a dual-compartment Hodgkin–Huxley framework, the neuron is divided into a “soma–basal dendrite unit” and an “apical dendrite unit,” accounting for voltage polarization induced by external fields. Using phase-locking ratio curves and three-dimensional parameter response surface, we systematically characterized neuronal sensitivity to field parameters and examined how potassium equilibrium potential ($V_K$) and extracellular resistance ($R_{\mathrm{out}}$) modulate these responses. Our results demonstrate that increasing $R_{\mathrm{out}}$ enhances neuronal responsiveness to external fields, while $V_K$ variations primarily regulate intrinsic excitability. These findings provide mechanistic insights into the frequency-dependent modulation of neuronal responses under weak electric fields, consistent with phenomena observed in biological neural systems, and provide a mechanistic and theoretical framework for understanding the joint effects of electric field amplitude and frequency on neuronal sensitivity to weak electric fields, which may help inform future neuromodulation strategies. Full article

In battery systems, external mechanical compression is commonly applied to pouch/prismatic cells to improve their electrical performance and mechanical integrity. However, cell clamping can hinder system heat rejection by introducing an additional thermal insulation layer. A novel battery clamping scheme was designed with reduced contact area to explore the system thermal behaviour under different cooling regimes. Experimental data obtained from battery characterisation and performance tests is analysed with a thermal-coupled equivalent circuit model to quantify changes in cell impedance and system thermal properties. By reducing the clamping area by 70%, the temperature rise of the cell was decreased by 0.5 °C in comparison to the reference condition of a cell with no clamping during a 1C discharge under natural convection. Under immersion cooling using BOT2100 dielectric liquid, the thermal benefit was amplified, resulting in temperature reductions of 0.9 °C at 1C and 4 °C at 3C. The principal conclusion of this work is that reshaping the clamping plate has the potential to reduce ohmic heating by lowering battery internal resistance, which outweighs the additional thermal resistance introduced by partial surface coverage. This novel experimental approach demonstrates the potential to improve battery thermal management through geometry-optimised cell clamping, particularly for high-power applications, and further directs the community towards cell clamping solution designed to optimise both thermal and mechanical cell performance. Full article

Electrical resistivity tomography (ERT) serves as an auxiliary tool for marine engineering geological investigation. Through modeling, the effectiveness of this method was evaluated in areas affected by hydrological and underwater environmental changes, with a focus on the submarine geological structure in nearshore environments. The effects of pore water mineralization and cation exchange capacity on the resistivity of seabed sedimentary layers were investigated via rock physics modeling, and the corresponding relationship curves were obtained. Physical simulation experiments were also conducted to validate the rock physics modeling results. This process quantitatively analyzed the factors influencing the resistivity of nearshore seabed sediments, obtained the resistivity of each sedimentary layer, and interpreted the causes of resistivity variations. Resistivity models of different terrains were established for sandy clay seabed sediments with varying water salinities. The innovative use of submarine electrical resistivity tomography was proposed, and its feasibility and advantages were confirmed through numerical simulations. Field tests along the Baltic Sea coast demonstrated that, compared with previous methods, submarine electrical resistivity tomography offers higher resolution and improved exploration performance. Full article

For Unmanned Aerial Vehicles (UAVs), optical sensing for reliable landing and the detection of the landing area is a crucial element. In low-light conditions, at night, and in foggy weather, where optical sensing is not feasible, thermal imaging can be utilised. Although this situation has been widely researched, most UAV landing approaches rely on GNSS assistance or single-mode detection, which limits their robustness and scalability in real-world operations. This study proposes an actively heated thermal helicopter landing pad designed using electrically powered resistive heating elements and a high-emissivity surface coating. Furthermore, optical and thermal images collected during actual UAV flight experiments under daytime and night-time conditions were processed using image fusion techniques with AVGF, DWTF, GPF, LPF, MPF, and HWTF fusions, and their performance in deep learning models was compared. The obtained optical, thermal, and fused datasets are used to train and evaluate deep learning-based helicopter landing pad detection models based on the YOLOv8 architecture. Experimental results show that models trained with single-mode data exhibit limited cross-domain generalisation, while fusion-based learning significantly improves detection robustness in optical and thermal domains. Among the evaluated methods, LPF, MPF and HWTF provide the most consistent performance improvements. The findings indicate that electrically heated thermal helicopter landing pads, when combined with image fusion and deep learning-based detection, can increase the landing detectability of UAVs at night and in low-visibility conditions. This detection-focused approach contributes to UAV flight safety by enhancing the visibility of the landing area without relying on active infrared markers or additional navigation infrastructure. Full article

In this work, the impact of hydrogen plasma treatment on the electrical and electronic quality of multicrystalline silicon (mc-Si) was systematically investigated using plasma-enhanced chemical vapor deposition (PE-CVD). Hydrogen radicals generated in the plasma effectively passivate dangling bonds, reducing electrically active defects and enhancing material quality. Optimized PE-CVD conditions were applied to promote efficient hydrogen incorporation and surface modification. Optical characterization, including reflectivity measurements and FT-IR spectroscopy, confirms the formation of Si–H bonds and a significant reduction in surface reflectivity of up to 66% at 600 nm. Electrical and optoelectronic analyses reveal pronounced improvements in carrier lifetime and diffusion length, increased by 200% and 79%, respectively. In addition, dark current–voltage (I–V) measurements show a 32% decrease in series resistance and a 51% increase in shunt resistance, indicating enhanced charge transport and suppressed leakage currents. These macroscopic electrical improvements are supported by light beam-induced current (LBIC) measurements, which demonstrate a 14% increase in grain boundary current, confirming effective hydrogen passivation and reduced recombination. Overall, hydrogen plasma PE-CVD treatment is shown to significantly improve the electronic quality and photovoltaic performance of mc-Si solar cells. Full article

Additive manufacturing by Selective Laser Melting (SLM) or, precisely, Laser Powder Bed Fusion (L-PBF), offers new opportunities for producing electrically functional metal components with tailored geometric designs and material properties. In this study, the electrical contact resistance and related properties of 3D-printed samples made from Al5086 aluminum alloy are tested. The benefits of Al5086 include flexibility without cracking, welding ability and exceptional resistance to corrosion in saltwater and industrial environments. This makes it an excellent candidate for power electric applications due to its good electrical conductivity and corrosion resistance. In this study, an analysis is performed to assess the impact of internal volumetric properties and surface parameters on general contact resistance performance. This analysis combines advanced testing procedures and parameter identification of the electric contact resistance model. This study investigates how these parameters affect contact resistance, which is a critical factor in the reliability of electrical devices. Electrical contact resistance was measured using a dedicated test setup that applied consistent pressure and maintained directional alignment. The results show that the printing direction of the samples slightly affects resistance values due to the continuity of current paths along the build direction, likely due to homogenous inter-layer boundaries and mechanical stress distribution. These findings suggest that both print orientation and internal structure must be considered when designing 3D-printed contact elements for electrical applications. Overall, this study demonstrates the feasibility of using L-PBF-fabricated aluminum components in electric applications where both electrical and structural performances are essential. Full article

The purpose of any electrode in die-sinking EDM is to transmit electrical impulses that facilitate workpiece erosion with minimum or no self-erosion. The performance of the electrode depends on the properties of the material that it is made of, application, and the workpiece material. This study focused on employing intensive machining regimes that increase productivity while maintaining electrode wear as low as possible to enhance cost-effectiveness. The experimental tests were organized using the response surface method and the analysis of the results is based on the ANOVA method. The findings revealed that the WCu 75/25 outperforms the other two in wear resistance and CuZn39Pb2 is the most wear prone. It was revealed that WCu 75/25 electrode at Ip ≈ 90 A and Ton between 360 and 390 µs represents the globally best solution for a minimum wear. Full article

Ethylene–propylene–diene monomer rubber (EPDM) is commonly used as a gas-tight sealing material in electrical equipment. Factors such as media exposure, thermal oxidative stress, and abrasion frequently cause deterioration of EPDM’s mechanical properties, significantly compromising the reliability of electrical equipment. Traditional activator ZnO provides limited enhancement to the properties of EPDM. The reaction between Zn²⁺ on the surface of zinc oxide interacts with the accelerator during curing of rubber, forming zinc chelates, which interact with sulfur to form zinc polysulfide complexes. But the release of zinc complexes has adverse effects on humans and ecosystems. To reduce ZnO usage and further improve the performance of EPDM in terms of mechanical properties and aging resistance, zeolitic imidazolate framework-8 (ZIF-8) is developed as a multifunctional additive in this work. Mechanical testing demonstrates that the incorporation of ZIF-8 enhances the mechanical performance and resistance to thermal oxidative aging of EPDM. Crosslink density testing, FTIR, and XPS show that ZIF-8 promotes the crosslinking reaction during rubber curing, resulting in improved mechanical performance for EPDM. Analysis of crosslinking density testing and SEM images shows that EPDM-ZIF-8 composite exhibits a slower increase in crosslinking density during thermal oxidative aging. TGA results indicate that ZIF-8 enhances the thermal stability of EPDM, which leads to improved aging resistance properties. This study provides new insights for the design and development of rubber composite materials, offering a reliable solution to the challenge of seal failure in electrical equipment. Full article

Temperature control and crack prevention are crucial for mass concrete structures in cold regions. Electrically conductive roller-compacted concrete (ERCC) provides a promising route to shift surface temperature regulation from passive protection to active control. To develop an ERCC material suitable for engineering applications, this study first established a quantitative relationship between interparticle interaction energy and particle spacing to elucidate the effect of carbon black (CB) dispersion and agglomeration on concrete performance. The dispersion quality of CB was then evaluated by sedimentation tests, UV absorbance, and resistivity measurements. The absorbance of CB suspensions containing PCE, SDS, and TA increased by 79.9%, 80.1%, and 100.4%, respectively, compared with the suspension without dispersant, and TA gave the lowest mortar resistivity. Mechanical tests and mesoscopic simulations showed that coarse aggregate volume fraction and CB dosage had stronger effects on the compressive strength and elastic modulus of ERCC than aggregate gradation and specimen size. After calibration using the ERCC-2-TA mixture, the average errors between simulation and experiment were 0.7% for compressive strength and 0.4% for elastic modulus. For engineering applications, the recommended ERCC parameters were a coarse aggregate volume fraction of 40%, a CB content of 4–5% and a water-to-binder ratio of 0.45–0.50 for roads, and a CB content of 8% with a water-to-binder ratio of 0.55 for dams. Full article

While membrane technologies are critical for preventing microplastics (MPs) release into aquatic ecosystems, MPs-induced fouling remains a persistent bottleneck, necessitating energy-intensive cleaning strategies that introduce their own environmental burdens. This study presents a systematic life cycle assessment (LCA) of fouling mitigation strategies, rigorously comparing hydraulic forward flushing and nitrogen (N₂) gas scouring across both unmodified and plasma-modified (acrylic acid, cyclopropylamine, and hexamethyldisiloxane) polysulfone membranes. Results reveal a stark divergence between operational performance and environmental sustainability. Baseline operations and the hydraulic flushing of unmodified membranes have environmentally costly global warming potential (GWP) ~150 kg CO₂-eq/m³), driven primarily by high electricity consumption and frequent membrane replacement. Conversely, cyclopropylamine (CPAm) plasma-modified membranes emerging as the optimal strategy, reducing global warming potential to 68 kg CO₂-eq/m³ and cutting electricity demand by 44% through superior fouling resistance. Crucially, the study uncovers a significant trade-off regarding gas scouring: While it achieves the highest technical performance (minimal flux decline of 0.33% h⁻¹), the upstream burdens of N₂ supply increased environmental impacts by over 100% across all categories. These findings challenge the assumption that maximum fouling control equates to sustainability, suggesting that surface engineering via plasma modification, rather than aggressive physical cleaning, offers the most viable pathway for sustainable MPs remediation. Full article

In this study, CuCr50Ni_X (X = 0, 0.1, 0.5, and 0.9 wt.%) coatings were successfully fabricated on a pure copper substrate via infrared-blue hybrid laser cladding. The effects of Ni addition on the microstructure, mechanical and electrical properties, and arc erosion resistance under 24 V/30 A conditions were systematically investigated. The results demonstrate that Ni refines the Cr phase and promotes the formation of a (Cr, Ni) solid solution and nanoscale Cr₇Ni₃ precipitates during non-equilibrium solidification. The coating with 0.5 wt.% Ni exhibits optimal comprehensive performance. It achieves a high microhardness of 174.2 HV_0.5, representing a 149% increase compared to the copper substrate (72 HV_0.5). Simultaneously, it maintains a good electrical conductivity of 29.8% IACS. Arc erosion morphology transforms from localized deep pits (CuCr50) to uniform, shallow characteristics (CuCr50Ni_0.5), accompanied by reduced cathode mass loss. This enhanced performance is attributed to the refined and dispersed Cr distribution, which facilitates dynamic arc root movement, together with improved phase boundary stability conferred by the (Cr, Ni) solid solution and Cr₇Ni₃ precipitates. This work provides a novel strategy for developing high-performance, long-life electrical contact components through surface alloying design and laser additive manufacturing. Full article

Sikkim, located in the northeastern Himalaya, is highly vulnerable to natural hazards and increasing depletion of surface and subsurface water resources, particularly springs and lakes. In South Sikkim, several lakes exhibit rapid drainage behavior, among which Nagi Lake shows near-complete water loss shortly after rainfall, indicating the presence of subsurface leakage pathways. This study investigates shallow subsurface moisture dynamics and identifies potential seepage-prone zones beneath the Nagi Lake basin using geoelectrical methods. Electrical resistivity profiling was conducted along seven survey lines during the non-rainy season (October–November 2025) to minimize the influence of transient rainfall-induced moisture variations. Profiling was carried out using the Wenner method, achieving investigation depths of approximately 6.5–9 m. Additionally, Vertical Electrical Sounding (VES) using the Schlumberger configuration was performed at selected locations to examine deeper subsurface conditions. Resistivity results indicate that profiles L1, L2, L3, L4, and L7 contain relatively higher moisture restricted to the upper ~5 m, whereas profiles L5 and L6 exhibit persistently low resistivity values from the surface to depths of ~9 m, suggesting sustained subsurface moisture accumulation. The downward extension of low-resistivity zones along L5 and L6 indicates possible preferential seepage pathways or localized subsurface water storage. VES results further reveal a higher density of subsurface anomalies below ~14 m in these areas. These low-resistivity anomalies are interpreted as potential subsurface flow pathways. Although confirmation of active seepage requires additional hydrological or time-lapse investigations, the findings provide important baseline geophysical insights for lake rejuvenation. Full article

Nd₂NiO_4+δ was investigated as a Ruddlesden–Popper (RP) cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs), with particular emphasis on its electrochemical performance and oxygen reduction reaction mechanism. The material was synthesized via a polymeric sol–gel route derived from Pechini’s method and evaluated in symmetric cells using Ce_0.9Gd_0.1O_2−δ (GDC) as the electrolyte. X-ray diffraction confirmed the formation of a single RP phase and good chemical compatibility with GDC after thermal treatments at 800 °C. Cathode layers with thicknesses of 8–12 µm were deposited by dip-coating. Electrical conductivity measurements revealed a thermally activated semiconducting behavior governed by Ni²⁺/Ni³⁺ small-polaron hopping, with an activation energy of ~1.08 eV. Electrochemical impedance spectroscopy showed a strong temperature dependence of the area-specific resistance, decreasing from 9.18 Ω·cm² at 600 °C to 0.39 Ω·cm² at 800 °C. Distribution of relaxation times (DRT) analysis enabled the identification of the dominant electrochemical processes, indicating that oxygen surface exchange reactions are more favorable than charge transfer at the cathode–electrolyte interface, which remains the main limiting step. These results demonstrate that Nd₂NiO_4+δ is a promising cathode for IT-SOFC operation, while further optimization of the electrode–electrolyte interface is required to enhance its oxygen reduction kinetics. Full article

The study focused on the development and optimization of plastic deformation of pure M1E copper using an unconventional hydrostatic extrusion (HE) process aimed at improving the performance of electrodes used in electrical discharge machining (EDM). The process was designed to refine the microstructure while maintaining the high electrical conductivity required for EDM applications. Optimization of a three-stage HE process (cumulative strain ε = 2.51) resulted in the formation of an ultrafine-grained structure (d₂ ≈ 370 nm), leading to a significant increase in mechanical strength (UTS ≈ 400 MPa) while preserving very high electrical conductivity (~99% IACS). This combination of properties is particularly important for EDM electrodes, as it allows improved wear resistance without compromising electrical performance. Due to the application-oriented nature of the study, the HE-processed copper was tested under industrial EDM conditions. Wear tests were conducted using seven electrodes of different geometries required for the production of a sample injection mold. The results demonstrated a substantial reduction in electroerosion wear of HE-processed electrodes (30–90%) compared with undeformed copper, together with up to 25% improvement in surface quality. These findings indicate that hydrostatic extrusion is an effective method for producing high performance EDM electrode materials with improved durability and machining quality. Full article

Ionic polymer–metal composites consist of an ion-conducting polymer–gel membrane sandwiched between two flexible electrodes, representing a class of soft electroactive materials capable of large deformation under low voltage. The gel membrane, swollen with solvent, facilitates ion migration under an electric field, enabling actuation. Tailoring the interfacial architecture between the electrode and the polymer–gel membrane is pivotal for advancing high-performance IPMC actuators. This study presents a comparative investigation of three core–shell nanocomposite electrodes, fabricated via in situ polymerization, for IPMC applications. Among these, the polyaniline-coated multi-walled carbon nanotube composite exhibits a deliberately designed hierarchical structure, with a specific surface area of 32.345 m²·g⁻¹ and a conductive doped polyaniline shell, as confirmed through XPS analysis. This optimized interface enables superior charge storage and transport, endowing the corresponding electrode with a specific capacitance of 40.28 mF·cm⁻² at 100 mV·s⁻¹—3.2 times greater than that of conventional silver-based electrodes—along with a reduced sheet resistance. When integrated with a Nafion ion–gel membrane, the PANI@MWCNT electrode achieves a 67% increase in force density and a larger displacement output compared to standard devices, directly correlated with its enhanced electrical and electrochemical properties. This work highlights the critical role of core–shell interfacial engineering in governing electromechanical performance at the electrode–gel interface and offers a practical design strategy for developing high-performance, cost-effective IPMC actuators for soft robotics, flexible electronics, and related applications. Full article