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The present work focuses on the synthesis of novel heterocycles 2-(aryloxy)-3-(4,5-diaryl-1H-imidazol-2-yl)quinolines (6k-v) by an effective condensation reaction. These molecules exhibited fluorescent properties and hence for the proper understanding of their optical behavior and quantum yields, solvatochromic studies have been carried out. Further, frontier molecular orbitals, molecular electrostatic potential (MEP), and geometrical structure optimization have been investigated using the B3LYP/6-311G ++ (d, p) method. The energy gap between the HOMO, LUMO of the optical and energy band gap is determined by DFT and UV–visible spectra for TD-DFT studies are done. The screening of these compounds for in vitro COX-1 and COX-2 inhibition and DPPH free radical scavenging ability assays produced promising results. The binding interactions of these molecules against the COX-2 enzyme (PDB: 5IKR) were validated by docking studies. [ABSTRACT FROM AUTHOR]

The performance of relevant detectors may be limited by the high dark current, low noise equivalent power, and photo-response. Graphene is a promising choice for low light intensity detection as a two-dimensional material. In this paper, a self-powered metal-graphene-metal photodetector with a 1 nm graphene layer, working in the range of 0.1–0.3 μm is designed and evaluated, which can be used in the free space optical communication, wearable modules, and imaging. The main mechanism governing the detection process is the photo-thermoelectric effect, an indirect method in which the incident light energy is initially converted to thermal energy and consequently to an electric potential due to the resulting temperature gradient. The large dark current is one major problem with the conventional metal-semiconductor-metal photodetectors. The proposed structure provides an ultra-low dark current density as low as 1.5 × 10− 20 A/cm2 and, thereby, a very low thermal noise of IJohnson=5 × 10− 22 A, which can be attributed to the high Schottky barrier in the graphene/contact interface. In addition, the responsivity of about 0.0453 A/W and the detectivity of 6.52 × 1017 Jones are obtained for the proposed photodetector, comparable to the characteristics of the conventional photodetectors using two-dimensional materials. [ABSTRACT FROM AUTHOR]

N-(2-(diphenylphosphino)ethyl)-4,6,7-trifluoro-2,1,3-benzothiadiazol-5-amine (Ph2PCH2CH2NH-btd-F3 (PCCN)) is prepared by the reaction of 4,5,6,7-tetrafluoro-2,1,3-benzothiadiazole (btd-F4) with 2-(diphenylphosphino)ethyl-1-amine (Ph2PCH2CH2NH2) leading to the nucleophilic substitution of F– by a phosphinamide fragment (Ph2PCH2CH2NH)– in btd-F4. Phase 1 (a product of cocrystallization of PCCN (85%) and its oxide Ph2P(O)CH2CH2NH–btd-F3 (POCCN, 15%)) is obtained by the separation of the mixture of products by thin-layer chromatography and subsequent evaporation of the solution. POCCN is obtained preparatively using the oxidation of PCCN by hydrogen peroxide. Phase 1, two polymorphs of POCCN (2 and 4), and the POCCN·C6H6 solvatomorph (3) are characterized by XRD. The P–C–C–N fragment in these phases adopts either a bent gauche-conformation with an intramolecular N–H⋯O hydrogen bond or an anti-conformation stabilized by a pair of intermolecular hydrogen bonds combining the molecules into a dimer. According to the DFT data, gauche-POCCN has a larger negative electrostatic potential at F and N than anti-POCCN, i.e. the btd-F3 fragment of the first conformation is more likely to participate in predominantly electrostatic intermolecular interactions. [ABSTRACT FROM AUTHOR]

Wound dressing is an ancient technique for promoting healing, and modern technology has led to the development of advanced dressings that enhance patient care. Nanofiber-based wound dressings are a medical innovation with enhanced properties, including improved adhesion, reduced infection rates, and increased tissue regeneration. This article focuses on electrospun nanofibrous wound dressing materials produced using the widely adopted method of electrospinning. This article explores several parameters that influence fiber size, including electrical conductivity, electric potential, collector distance, viscosity, flow rate, and surface tension. With Fucoidan (FUC) loading, an increase in the fiber diameter of the control group from 310 nm to 395 nm was observed. This research also examines the use of Halomonas Levan (HL), a polysaccharide, and polyvinyl alcohol (PVA) polymer as wound dressing materials to enhance the mechanical properties of the latter. The incorporation of various concentrations of FUC into PVA-HL electrospun nanofibers yielded diverse effects on tensile strength: an enhancement was observed in the PVA-HL-10FUC formulation, while reductions were noted in the PVA-HL-13FUC and PVA-HL-15FUC formulations. The WST1 assay demonstrated that none of the samples exhibited cytotoxicity up to 72 h, as cell viability increased over time. In conclusion, nanofibrous PVA-HL structures loaded with FUC, which promote tissue regeneration and prevent infection, could be considered a novel wound dressing material. [ABSTRACT FROM AUTHOR]

We construct the low-frequency formulation of the turbulence characterizing the plasma in a Tokamak edge. Under rather natural assumptions, we demonstrate that, even in the presence of poloidal magnetic fluctuations, it is possible to deal with a reduced model for turbulence dynamics. This model relies on a single equation for the electric potential from which all the physical turbulent properties can be calculated. The main result of the present analysis concerns the existence of a specific Fourier branch for the dynamics which demonstrate the attractive character of the two-dimensional turbulence with respect to non-axisymmetric fluctuations. The peculiar nature of this instability, affecting the non-axially symmetric modes, is discussed in some detail by recovering two different physical regimes. [ABSTRACT FROM AUTHOR]

Water pollution involves the coexistence of microplastics (MPs) and traditional pollutants, and how can MPs influence the adsorption of other pollutants by biochar during the treatment process remains unclear. This study aimed to investigate the influence of polystyrene microplastics (PS MPs) on the adsorption of cadmium (Cd) and ciprofloxacin (CIP) by magnetic biochar (MTBC) in the single and binary systems. MTBC was prepared using tea leaf litter; the effects of time, pH, and salt ions on the adsorption behaviors were investigated; and X‐ray photoelectronic spectroscopy (XPS) and density flooding theory analysis were conducted to elucidate the influence mechanisms. Results indicated that PS MPs reduced the pollutants adsorption by MTBC due to the heterogeneous aggregation between PS MPs and MTBC and the surface charge change of MTBC induced by PS MPs. The effects of PS MPs on heavy metals and antibiotics adsorption were distinctly different. PS MPs reduced Cd adsorption on MTBC, which were significantly influenced by the solution pH and salt ions contents, suggesting the participation of electrostatic interaction and ion exchange in the adsorption, whereas the effects of PS MPs on CIP adsorption were inconspicuous. In the hybrid system, PS MPs reduced pollutants adsorption by MTBC with 66.3% decrease for Cd and 12.8% decrease for CIP, and the more remarkable reduction for Cd was due to the predominated physical adsorption, and CIP adsorption was mainly a stable chemisorption. The influence of PS MPs could be resulted from the interaction between PS MPs and MTBC with changing the functional groups and electrostatic potential of MTBC. This study demonstrated that when using biochar to decontaminate wastewater, it is imperative to consider the antagonistic action of MPs, especially for heavy metal removal. Practitioner Points: Magnetic biochar (MTBC) was prepared successfully using tea leaf litter.MTBC could be used for cadmium (Cd) and ciprofloxacin (CIP) removal.Polystyrene microplastics (Ps MPs) reduced Cd/CIP adsorption by MTBC.Ps MPs effects on Cd adsorption were more obvious than that of CIP.Ps MPs changed the functional groups and electrostatic potential of MTBC, thus influencing MTBC adsorption. [ABSTRACT FROM AUTHOR]

Context: The study of platinum (Pt) clusters and nanoparticles is essential due to their extensive range of potential technological applications, particularly in catalysis. The electronic properties that yield optimal catalytic performance at the nanoscale are significantly influenced by the size and structure of Pt clusters. This research aimed to identify the lowest-energy conformers for Pt 18 , Pt 19 , and Pt 20 species using Density Functional Theory (DFT). We discovered new low-symmetry conformers for Pt 19 and Pt 20 , which are 3.0 and 1.0 kcal/mol more stable, respectively, than previously reported structures. Our study highlights the importance of using density functional approximations that incorporate moderate levels of exact Hartree-Fock exchange, alongside basis sets of at least quadruple-zeta quality. The resulting structures are asymmetric with varying active sites, as evidenced by sigma hole analysis on the electrostatic potential surface. This suggests a potential correlation between electronic structure and catalytic properties, warranting further investigation. Methods: An equivariant graph neural network interatomic potential (NequIP) within the Atomic Simulation Environment suite (ASE) was used to provide initial geometries of the aggregates under study. DFT calculations were performed with the ORCA 5 package, using functional approximations that included Generalized Gradient Approximation (PBE), meta-GGA (TPSS, M06-L), hybrid (PBE0, PBEh), meta-GGA hybrid (TPSSh), and range-separated hybrid (ω B97x) functionals. Def2-TZVP and Def2-QZVP as well as members of the cc-pwCVXZ-PP family to check basis set convergence were used. QTAIM calculations were performed using the AIMAll suite. Structures were visualized with the AVOGADRO code. [ABSTRACT FROM AUTHOR]

In this study, we performed HOMO-LUMO energy calculations, molecular electrostatic potential surface (MEPS), optimized molecular geometry using B3LYP, B3PW91 methods and 6-311G(d,p) basis set of the target molecule (E)-methyl 3-(1-(4-methoxybenzyl)-2,3-dioxoindolin-5-yl) acrylate (MMDA) that is an isatin derivative, nonlinear optics (NLO), NBO analysis to investigate the stability of the molecule as a function of both hyper-conjugative interactions, charge transfer within the molecule and charge delocalization, and Mulliken atomic charge structure were examined using the Gaussian 09 software, and the results were displayed. In this study, ADME analysis was performed to analyze the problem of our molecule finding application in the field, focusing on producing effective and harmless pharmacological drugs. Finally, molecular docking analysis of the examined compound on melanoma cancer were performed with two different enzymes (PDB:3OG7) and (PDB:5EG3), and docking scores and receptor models were given. [ABSTRACT FROM AUTHOR]

The doubly-fed induction generator (DFIG) is vulnerable to overcurrent at the stator winding and overvoltage at the DC link due to voltage drop after the grid fault. The large wind farm may have a capacity of several million MWs, whose tripping yields a notable power imbalance and frequency drop in the power systems, which may be avoided by the low-voltage ride-through (LVRT) strategies implemented with the hardware or software. The latter has the merits of low cost and easy to realize, thus studied in this paper. Considering the grid fault uncertainty and DFIG parameters' correlation, this paper newly introduces the sliding mode structure into the passive control to improve the performance of the inner current control loop of the rotor-side converter (RSC), thus proposing a passive sliding mode control (P-SMC) based RSC control strategy to improve the LVRT capability of the DFIG. The time domain analysis with different fault severities, i.e., voltage drops, at the point of public coupling (PCC) is performed. The simulation results with the P-SMC control or not are obtained and compared to verify the control effect and the robustness of the proposed LVRT strategy. This study is beneficial for maintaining power system security against fast-increasing wind power. [ABSTRACT FROM AUTHOR]

Induction motors are the most common type of motor in power systems, constituting approximately 70–90% of the dynamic loads, making them significant contributors to system dynamics. In transient voltage stability analysis, dynamic equivalent models are commonly used to simplify the representation of a group of induction motors. This paper presents a method for the grouping and aggregation of induction motors at a common bus. Firstly, grouping rules are provided for clustering induction motors into several subgroups based on the mechanical principles of rotor force and motion, and aggregation rules are provided for aggregating a motor subgroup into a single-unit model based on the relationship between voltage drop and power transmission in distribution networks. Secondly, guided by the grouping rules, high-speed remaining electromagnetic torque and low-speed remaining electromagnetic torque are defined as new clustering indicators, and an adaptive K-means clustering method using silhouette coefficient verification is introduced to obtain the optimal motor subgroups. Thirdly, guided by the aggregation rules, a dynamic equivalent method is further introduced to obtain the equivalent single-unit model from a motor subgroup. Lastly, a transient voltage stability simulation in a typical distribution network is presented to illustrate that the proposed clustering and equivalent methods are more reasonable, accurate, and effective than traditional methods, as the obtained model has better dynamic characteristics and can more accurately reproduce the process of voltage collapse. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are transforming the transportation sector, driven by the rapid expansion of charging infrastructure, including fast-charging stations (FCSs), significantly reducing charging time compared to standard charging stations. Despite the advantages of faster charging, the substantial power demand of EVs poses significant technical challenges for distribution networks. In particular, the existing literature has a research gap regarding how FCSs may impact or interact with step-voltage regulators' (SVRs) tap operations. In this study, we characterize and evaluate the effects of fast recharging at varying penetration levels (PLs) on SVRs' tap operations using probabilistic simulations and sensitivity analysis. To address these challenges, we propose a local and innovative application of the Volt/Var control on EV fast charging. The proposed application aims to inject reactive power into the network, depending on the FCS's nominal active power, when the bus voltage connected to the FCS exceeds a minimum value. Our research on an actual feeder in northern Brazil reveals that reducing the active power supplied to the vehicle or oversizing the charging station power converters is unnecessary. Furthermore, our strategy reduces the probability of undervoltage violations and minimizes SVR tap changes, mitigating EVs' impact on voltage quality. [ABSTRACT FROM AUTHOR]

Polyelectrolyte brushes (PEBs) are commonly used to modify surface that have attracted great research interest. The dielectric permittivity of the grafted surface is typically significantly different from that of solution, which results in surface polarization (SP) effect with a jump of electric field. It is thus important to study how SP alters the PEB's structure and properties. In this work, the SP effects on PEB structure was studied using a statistical thermodynamic theory. The free energy functional to describe SP effect was constructed by using the image-charge method. Meanwhile, the electrostatic potential was solved from a modified Poisson-Boltzmann equation taking the ion solvation effect into consideration. In the absence of SP, the thickness of PEB exhibited a continuous collapse transition when decreasing the solvent quality. In the presence of SP, the collapse became a jump-like transition. Free energy analysis showed that the long-range Coulombic interaction dominated the transition because of the enhanced counterion condensation in the presence of SP. The theory provides an effective tool to study SP effect on PEBs, and the results explain the underlying physics in PEB collapse transition. [ABSTRACT FROM AUTHOR]

In this study, we have investigated a strategy for designing some novel pyrazoline-thiazole hybrids containing azo moiety. The synthesized compounds were structurally characterized and their antibacterial activity was in vitro evaluated against gram-negative and gram-positive bacteria using the inhibition zone method. The antibacterial activity of the tested compounds was moderate to good. Compound 12c showed the best activity compared to the standard drug (Ampicillin) against S. aureus and E. coli at the concentration of 0.16 mg/mL, with the highest inhibition zone diameters of 34 mm and 37 mm, respectively. Moreover, in silico molecular docking and ADME profile studies were investigated in order to understand the binding affinity and interactions along with the ADME properties of all designed hybrids. Additionally, Density functional theory (DFT) calculations were carried out at the B3LYP/6-311G++ level of theory. The study involved an examination of the optimized geometry, molecular electrostatic potential map, and the HOMO → LUMO electronic energy gap. In accordance with the findings, the newly synthesized hybrids could be beneficial for medicine and exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

This study computationally investigates the properties and competition of complexes formed by the interaction between hypohalous acids (HOX, where X = F, Cl, Br, and I) and carbonyl selenide (COSe) at the MP2/aug-cc-pVTZ computational level. Three distinct groups of complexes were obtained. The first group, consisting of complexes with a cyclic structure (HB-TB), exhibited the highest stability. remaining two groups formed less stable linear structures with different characteristics (ChB and XB). In the first group, the electronegativity of the halogen atom significantly influenced the stability of the complexes. Conversely, the stability of complexes in groups II and III was primarily determined by the acid and base strengths of the interacting monomers. To comprehensively evaluate the obtained results, various analyses were employed, including Molecular electrostatic potential (MEP), geometry Optimization, Spectroscopic, Interaction energy (SE), Natural bond orbital (NBO) analysis, Atoms in molecules (AIM) analysis, Non-covalent interaction (NCI) index, Energy decomposition analysis (EDA), and Electron density difference(EDD) analysis. [ABSTRACT FROM AUTHOR]

Some novel FeIII, CuII, and PdII chelates incorporating N′‐(1‐methyl‐2‐oxoindolin‐3‐ylidene)benzohydrazide (MIBA) were fabricated. The tested compounds were investigated using thermogravimetric analysis (TGA), CHN, spectra analysis (IR, mass spectra, and NMR), melting point, magnetic moments, molar conductance, ultraviolet–visible spectroscopy, powder X‐ray diffraction, and computational studies. The conductance results showed that the tested FeIII, CuII, and PdII chelates are electrolytes. Magnetic and electronic spectra are applied to deduce the coordinating ability of the tested ligand, and the geometric structure of the studied chelates is found to be octahedral, distorted octahedral, and square planar for FeIII, CuII, and PdII chelates, respectively. The TGA study of these studied complexes displays that the hydrated H2O molecules, acetate, and nitrate are removed in the first and second degradation steps followed directly by degradation of the studied ligand leaving metal oxide as residue. The thermodynamic factors, like ΔS*, ΔH*, E*, A, and ΔG* are evaluated from the TGA curves and explained. The density functional theory (DFT)/B3LYP computation method was applied for the estimation of the molecular electrostatic potential (MEP; highest occupied molecular orbital [HOMO] and lowest unoccupied molecular orbital [LUMO]) energy for the studied compounds. In an in vitro study, the antimicrobial effects of the prepared compounds were screened on various strains of bacteria and fungi. It was found that tested compounds exposed a good biological efficacy through IC50 results close to reference drugs and antitumor potential against (MCF‐7, Hep‐G2, and HC‐T116) cell lines. The data obtained displayed that the studied chelates showed promising antitumor activity. The studied metal chelates were screened for in vitro antioxidant efficacy using DPPH assay. The studied compounds explained dynamic satisfying performance. Also, the crystal structures of breast cancer protein (PDB ID: 3HB5) and Escherichia coli (PDB ID: 2VF5) were performed by molecular docking simulation. Data of docking simulation suggestions are which tested compounds have biological behavior as well as have obvious benefit in the pharmaceutical business. [ABSTRACT FROM AUTHOR]

Summary: According to recent research work, increasing electric power generation is one of the significant advantages of the dual‐rotor wind turbine (DRWT) compared to the other types for the same wind speed. In this research work, a modified super‐twisting sliding mode control (STSMC) based on the neural network (NN) is suggested to regulate the stator powers of a DRWT‐based doubly‐fed induction generator (DFIG) in normal and unbalanced grid fault modes. The design of this strategy involves replacing the gains of conventional STSMC with the NN algorithm to enhance robustness, mitigate the impact of unbalanced grid voltage, and consequently improve the quality of the generated power of DRWT‐based DFIG. This forms the primary contribution of this work. The suggested strategy is compared with vector control (VC) and conventional STSMC in terms of reference tracking, power ripples, response dynamics, harmonic distortion of stator current, and the effect of an unbalanced grid fault. Finally, the utility and effectiveness of the designed controller are confirmed through computer simulations. Furthermore, when the grid is subjected to a 20% voltage drop, the results demonstrate that the suggested strategy reduced the total harmonic distortion (THD) value of the stator current by 12.92% compared to VC and by 9.29% compared to conventional STSMC. [ABSTRACT FROM AUTHOR]

This article examines the use of LEGO bricks as a tool for modeling physics phenomena in laboratory courses. The author provides examples of how LEGO bricks can be used to represent various concepts in physics, such as parabolic trajectories and oscillation graphs. The article also discusses the benefits of using LEGO bricks for inquiry-based learning and fostering students' comprehension and creativity in physics. While the author emphasizes the pedagogical value of LEGO bricks in physics education, they acknowledge the need for further research in this area. The article concludes by clarifying that it is not funded or sponsored by the LEGO company. [Extracted from the article]

Asphalt aging is a natural process that causes changes in the properties of asphalt, particularly in asphalt adhesion. Previous studies show that the effect of aging on asphalt adhesion performance is not uniform and depends on the asphalt source and aging conditions. To investigate the effects of different SARA (saturates, aromatics, resins, and asphaltenes) ratios and structural changes on the adhesive properties of asphalt after aging, this study employs molecular dynamics simulation to calculate asphalt properties such as density, viscosity, and work of adhesion. The above properties were computed for 12 categories of asphalt molecules, individual SARA components, and asphalt models characterised by diverse SARA ratios, followed by a correlation analysis. The study reveals that asphalt aging increases density, viscosity, and adhesion to silica. The increase in polar functional groups, namely ketone and sulfoxide, is responsible for the enhanced adhesion of asphalt to silica due to the resulting increase in electrostatic potential energy. Different SARA ratios lead to different asphalt properties, with the RA/SA index ((asphaltene%+resin%)/(saturate% + aromatic%)) showing a better correlation with the properties. Positive correlations were observed among density, viscosity, and work of adhesion. This study advances our understanding of chemical and structural effects on aged asphalt properties. [ABSTRACT FROM AUTHOR]

In this work, we present an analytical DC model for the Gallium Nimtide High Electron Mobility Transistor by taking into account the finite width of the two-dimensional electron gas (2DEG) layer. The model predicts the vertical electric field in the device, especially at the interface of AlGaN and GaN layers, electrostatic potential, and energy band diagram are also obtained by the model. The general form of Gauss's law including piezoelectric and spontaneous polarization effect is employed to obtain this model in different regions from top to bottom of the GaN-HEMT. The model solves electrostatic equations in all regions of the device including two narrow regions around the AlGaN/GaN interface with thicknesses of about 3 nm. This model demonstrates how the triangular quantum well is formed around the AlGaN/GaN interface and varies as a function of gate voltages. Using the proposed electrostatic analysis and the treatment proposed by the EPFL HEMT model, the DC current-voltage characteristics are obtained by this model. The results predicted by the model are validated with TCAD simulations and in part with the EPFL HEMT model. The proposed model facilitates the following steps toward obtaining a complete model for small signal and large signal analysis of GaN HEMT. [ABSTRACT FROM AUTHOR]

The current study deals with the theoretical enquiries of 1-acetyl-4-piperidinecarboxylic acid, a derivative of piperidine. The moiety of piperidine has extensive spread of usages in the field of pharmacology. Employing DFT techniques, theoretical analysis on the caption compound was performed and optimised molecular structure was obtained. Energy gap between HOMO and LUMO along with global reactivity parameters, NLO behaviour, molecular electrostatic potential studies were computed and analysed for the heading compound in gaseous & solvent phases (methanol, ethanol and acetone). On the chemical in the title, topology research such as ELF, LOL and RDG were conducted in different phases. Electron2013hole analysis on excited states was executed. The TD-DFT methodology has been used to assist in the scrutiny of the UV–visible spectra in dissimilar solvents. The energy of interaction and densities of electron of acceptor and donor bonds were computed using NBO research. To confirm the reactive sites in the molecule, Fukui functions were accomplished. Additionally, docking studies against antithrombotic targets were achieved employing autodock tools and drug-like characteristics were also discovered. The steadiness of the targeted proteins has also been projected using Ramachandran plots. [ABSTRACT FROM AUTHOR]

Metasurfaces are sub-wavelength patterned layers for controlling waves in physical systems. In optics, metasurfaces are created by materials with different dielectric constants and are capable of unconventional functionalities. We develop a deep-learning framework for Dirac-material metasurface design for controlling electronic waves. The metasurface is a configuration of circular graphene quantum dots, each created by an electric potential. Employing deep convolutional neural networks, we show that the original scattering wave can be reconstructed with fidelity over 95%, suggesting the feasibility of Dirac electron holography. Additional applications such as plane wave generation and designing broadband and multi-functionality electronic metasurface in graphene are illustrated. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the traditional short-circuit current calculation method is not applicable to Distributed Generation (DG) accessing the distribution network, the paper proposes a short-circuit current partitioning calculation method considering the degree of voltage drop at the grid-connected point of DG. Firstly, the output characteristics of DG in the process of low voltage ride through are analyzed, and the equivalent output model of DG in the fault state is obtained. Secondly, by studying the network voltage distribution law after fault in distribution networks under different DG penetration rates, the degree of voltage drop at the grid-connected point of DG is used as a partition index to partition the distribution network. Then, iterative computation is performed within each partition, and data are transferred between partitions through split nodes to realize the fast partition calculation of short-circuit current for high proportion DG access to distribution network, which solves the problems of long iteration time and large calculation error of traditional short-circuit current. Finally, a 62-node real distribution network model containing a high proportion of DG access is constructed on MATLAB/Simulink, and the simulation verifies the effectiveness of the short-circuit current partitioning calculation method proposed in the paper, and its calculation speed is improved by 48.35% compared with the global iteration method. [ABSTRACT FROM AUTHOR]

Dedicating more attention to renewable energies and power electronic improvements results in increased direct current microgrids (DC MGs) application. However, DC MGs have some challenges with voltage adjustment and power sharing. To do so, a two-layer hierarchical control structure, including a new fully distributed secondary control strategy and conventional primary droop control method, is proposed and employed in this paper to share power and swiftly adjust the voltage accurately. Indeed, a distributedaveraging proportional-integral (DAPI) secondary control strategy is introduced. Another problem in DC MGs is the existence of constant power loads (CPLs), which may result in instability. To overcome the problems caused by CPLs, a term based on the output voltage of CPL is added to the proposed DAPI to prevent instability. The required control inputs are obtained using localized data of the DC bus and their neighbor's secondary control inputs inspired by cooperative control. Besides, this strategy needs no knowledge of the microgrid topology, which enhances flexibility. For validating the proposed DAPI strategy in DC MGs, an islanded DC MG is simulated in the MATLAB/SIMULINK software. Comparing the results with those obtained from another existing method proves the performance of the proposed DAPI controller under different scenarios of plug-and-play, communication failure, and load changes. [ABSTRACT FROM AUTHOR]

This article investigates the behavior of two parallel layers of different miscible dielectric liquids enclosed and sandwiched between two electrodes. By applying an electric potential to one electrode while grounding the other, electro-convection occurs when the electric Rayleigh number exceeds a critical value, setting the fluid into motion and resulting in rapid mixing between the two liquids. A numerical model is developed to account for the varying ionic mobility and permittivity of the two liquids, considering their evolution based on the relative concentration field. The simulations confirm that electro-convection significantly enhances the mixing between the two liquids, as expected. Additionally, intriguing ripples are observed near the initial interface during the early stages of electro-convection instability growth. To explain and describe the flow dynamics in terms of stability analysis, a semi-analytical model is presented. This study provides insights into the mixing behavior and flow dynamics of miscible dielectric liquids under the influence of electro-convection. The findings contribute to a better understanding of the underlying mechanisms and can be valuable for applications such as microfluidics, energy conversion, and mixing processes. Further research is encouraged to explore additional parameters and optimize the control of electro-convection for practical applications. [ABSTRACT FROM AUTHOR]

The paper investigates the influence of magnetic fields on the non-simple concentration phenomenon in the complex-valued nonlinear Schrödinger equations with a constant electric potential$ (\mathbf i \varepsilon\nabla + \boldsymbol A)^2 u + u - |u|^{p-1} u = 0 \qquad \text{in }\mathbb R^N. $We demonstrate that a multi-peak solution always exists at a non-degenerate local maximum or minimum point of the Frobenius norm $ \|\boldsymbol B\|_{\mathcal{F}}^2 $, where $ \boldsymbol B $ is the magnetic field generated from the magnetic potential $ \boldsymbol A $. Interestingly, the locations of peaks form a regular simplex near such a maximum point. It is also surprising that at such a minimum point, we can find a two-peak solution, which is distinct from the real-valued case. This is unexpected given that the non-existence of a multi-peak solution at a non-degenerate local minimum point of the electric potential has been proven in [24]. [ABSTRACT FROM AUTHOR]

Accurate quantification of the uncertainty in the mechanical characteristics of dielectric solids is crucial for advancing their application in high-precision technological domains, necessitating the development of robust computational methods. This paper introduces a Conditional Generation Adversarial Network Isogeometric Analysis (CGAN-IGA) to assess the uncertainty of dielectric solids' mechanical characteristics. IGA is utilized for the precise computation of electric potentials in dielectric, piezoelectric, and flexoelectric materials, leveraging its advantage of integrating seamlessly with Computer-Aided Design (CAD) models to maintain exact geometrical fidelity. The CGAN method is highly efficient in generating models for piezoelectric and flexoelectric materials, specifically adapting to targeted design requirements and constraints. Then, the CGAN-IGA is adopted to calculate the electric potential of optimum models with different parameters to accelerate uncertainty quantification processes. The accuracy and feasibility of this method are verified through numerical experiments presented herein. [ABSTRACT FROM AUTHOR]

Industrial wireless mesh networks (WMNs) have been widely deployed in various industrial sectors, providing services such as manufacturing process monitoring, equipment control, and sensor data collection. A notable characteristic of industrial WMNs is their distinct traffic pattern, where the majority of traffic flows originate from mesh nodes and are directed towards mesh gateways. In this context, this paper adopts and revisits a routing algorithm known as ALFA (autonomous load-balancing field-based anycast routing), tailored specifically for anycast (one-to-one-of-many) networking in WMNs, where traffic flows can be served through any one of multiple gateways. In essence, the scheme is a hybrid-type routing strategy that leverages the advantages of both back-pressure routing and geographic routing. Notably, its novelty lies in being developed by drawing inspiration from another field, specifically from the movement of charges in an electrostatic potential field. Expanding on the previous work, this paper explores further in-depth discussions that were not previously described, including a detailed description of the analogy between an electrostatic system and a WMN system based on precise mapping perspectives derived from intensive analysis, as well as discussions on anycast, numerical methods employed in devising the ALFA scheme, its characteristics, and complexity. It is worth noting that this paper addresses these previously unexplored aspects, representing significant contributions compared to previous works. As a completely new exploration, a new scheduling strategy is proposed that is compatible with the routing approach by utilizing the potential-based metric not only in routing but also in scheduling. This assigns higher medium access priority to links with a larger potential difference. Extensive simulation results demonstrate the superior performance of the proposed potential-based joint routing and scheduling scheme across various aspects within industrial WMN scenarios. [ABSTRACT FROM AUTHOR]

Quasi-Z-source converters (QZSC) are gaining popularity because they operate in a single stage, use smaller components, and maintain continuous input current with a common ground. This converter is widely used in various applications that require a DC-DC converter. The small-signal analysis and linearization methods are often employed for controlling the Quasi-Z-source converters. The linear model of QZSC does not provide sufficient stability control over a wide range. Sliding Mode Control (SMC) is widely used in electronic power converters due to its variable structure. This paper presents a SMC for a QZSC with three objectives:1) to achieve stability across a wide range of QZSC; 2) to systematically select the proposed controller coefficients; and 3) to enable tracking of the reference voltage in spite of changes in input voltage, reference voltage, and output load. The simulations have been done with the help of MATLAB/Simulink and show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Electric tractors have many advantages, including high torque, excellent controllability, energy efficiency, a simple structure, and an electric interface for expansion. However, a significant limitation lies in their endurance. This study presents the design of an extended-range power supply system to ensure continuous endurance for an electric tractor. The objective is to provide a continuous power source for our self-developed electric tractor while preserving the benefits of electric propulsion. Extended-range power systems utilize a primary mover, typically an oil-fueled internal combustion engine, to drive the generator for electricity generation, and the generated AC-form electricity is subsequently converted into stable DC bus voltage by a power electronic converter. The hardware and control design of an extended-range power supply system are finalized and validated through experimental trials. The results demonstrate the system's capability to sustain stable DC bus voltage amidst disruptions such as sudden load shifts and fluctuations in the prime mover's speed. Even with a 50% sudden load change, the voltage drop is within 12% and can recover to ±3% within 4 s. The extended-range can be used alone without a battery to power the electric tractor, or it can used in parallel with other extended ranges or batteries for power sharing thanks to the droop control ability. [ABSTRACT FROM AUTHOR]

In this work, we propose a theoretical finite element description of the ionic profiles of a general mixture of n species of spherical charged particles dissolved in an implicit solvent, with arbitrary size and charge asymmetries, neutralizing a spherical macroion. This approach aims to close the gap between the nano- and the micro-scales in macroion solutions, taking into account the ion correlations and ionic excluded volume effects consistently. When these last two features are neglected, the classical non-linear Poisson–Boltzmann theory for n ionic species—with different ionic closest approach distances to the colloidal surface—is recovered as a limit case. As a proof of concept, we study the electrical double layer of an electroneutral mixture of oppositely charged colloids and small microions, with an asymmetry 1:333 in size and 1:10 in valence, in salt-free and added salt environments. Our theoretical approach displays a good agreement regarding the ionic profiles, the integrated charge, and the mean electrostatic potential obtained from molecular dynamics simulations with explicit-sized microions. Although the non-linear Poisson–Boltzmann colloid–colloid and colloid–microion profiles differ notably from those obtained via molecular dynamics simulations with explicit small-sized ions, the associated mean electrostatic potential agrees well with the corresponding explicit microion simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] Harnessing electrical energy from salinity gradients, particularly for powering micro and nanoscale devices, has become a focal point of recent research attention, due to its renewable and biocompatible nature. Much of the reported research in that direction revolves around optimizing the membrane architecture and the charge distribution to maximize the induced electric potential, with no particular emphasis on the fluid rheology. However, many of the modern miniature systems, typically the bio-inspired ones, concern fluids with complex rheological characteristics, where the results for Newtonian solvents may not trivially apply. Here, we hypothesize that the interplay between interfacial electro-mechanics and the fluid rheology can influence the effectiveness of salinity-gradient-modulated electrokinetics significantly – an aspect that has largely remained overlooked. Here we report the first experiments supplemented by a theoretical model that unveil how that the addition of polymers in a solvent modulates the salinity gradient – induced electric potential in a microfluidic channel. Our theoretical framework considers the simplified Phan-Thien Tanner (sPTT) constitutive model, which represents the viscoelastic characteristics of fluids. Experiments were conducted with combined pressure driven and salinity gradient driven flow through microchannel involving dilute solutions of polyethylene oxide (PEO) of different molecular weights and concentrations to successfully validate the theoretical approach. Our findings indicate that the induced electrical potential increased non-linearly with the saline concentration ratio across the microchannel, as compared traditional linear response. Our results demonstrate how the elasticity of fluid may enable realizing an optimal benefit to this effect, by arresting the viscous resistance and uplifting the elastic response via utilizing polymeric inclusions of high relaxation times. These results provide specific insights on preferential windows of augmenting the induced streaming potential by harnessing the viscoelastic nature of the solution and the imposed salt concentration, bearing critical implications in miniature energy harvesting and desalination technology. [ABSTRACT FROM AUTHOR]

Hall thrusters are electric propulsion devices widely used on spacecraft. The stability of Hall thrusters is often disturbed by low-frequency oscillations (LFOs) around 5–100 kHz, known as the 'breathing mode', typically observed through fluctuations in channel discharge current and plasma parameters. Experimental studies on Hall thrusters with a wide range of sizes show that LFOs exhibit distinct characteristics depending on the channel structures. The size of the channel can modify the particle-wall interactions, electric potential distribution, and electron temperature, thereby influencing the performance of LFOs. Furthermore, the long-term operation of thrusters can cause significant wall erosion, altering the geometry of the discharge channel, which further impacts LFOs. In this work, a one-dimensional fluid model is established to explore the influences of structure sizes and wall erosion of the channel on the LFO characteristics. Both the thruster channel and the plume region are included in the model, and a modified and more precise approach to calculating the electron energy loss at the wall is proposed, which takes into account the influences of secondary electron emission and the channel cross-sectional area. The simulation results indicate that choosing a narrower or longer channel structure has a significantly suppressing effect on LFOs. An erosion model is established according to the cited experimental data to construct the eroded channel structure and to investigate the effect of channel erosion on the breathing mode, which shows that wall erosion can exacerbate LFOs and impact the performance of the thruster. [ABSTRACT FROM AUTHOR]

Self-consistent 1D modeling of streamers in ammonia-oxygen-nitrogen-water mixtures has been performed in this work. A fluid model that includes species transport, electrostatic potential, and detailed chemistry was developed and verified. This model is then used to simulate the avalanche, streamer formation and propagation phases, driven by a nanosecond voltage pulse, at different thermochemical conditions derived from a 1D laminar premixed ammonia-air flame. The applicability of the Meek's criterion in predicting the streamer inception location was successfully confirmed. Streamer formation and propagation duration were found to vary significantly with different thermochemical conditions, due to the difference in ionization rates. The thermochemical state also affected the breakdown characteristics which was tested by maintaining the background reduced electric field constant. Detailed kinetic analyses revealed the importance of O (1 D) in the production of key radicals, such as O, OH, and NH2. Furthermore, the contributions of the dissociative electronic excitation of NH3 towards the production of H and NH2 radicals have also been reported. Spatial and temporal evolution of the electron energy loss fractions for various inelastic collision processes at different thermochemical states uncovered the input plasma energy spent of fuel dissociation and the large variability in the dominant processes during the avalanche and streamer propagation phases. The methodology and analyses reported in this work are key towards developing effective strategies for controlled nanosecond-pulsed non-equilibrium plasma sources used for ammonia ignition and flame stabilization. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional (3D) solution of static behavior of simply supported doubly curved functionally graded multilayered (FGM) magneto-electro-elastic shells subjected to mechanical, electric displacement, magnetic flux, electric potential and magnetic potential loads is presented. A coupling procedure based on the state space and the Runge–Kutta methods is elaborated for the 3D magneto-electro-elastic governing equations. An efficient semi-analytical approach is resulted for arbitrary functionally graded shells in thickness direction. The proposed mathematical modeling has been validated by several numerical tests. The obtained results are in good agreement with the available ones given by the three-dimensional asymptotic approach, the state space approach and a meshless collocation method. It has been revealed that, the loading conditions, the materials properties gradient index, the span-to-thickness ratio and the radius-to-thickness ratio remarkably influence the static response of FGM shells. [ABSTRACT FROM AUTHOR]

In this study, the modified exponential approach is used to investigate the fractional order longitudinal wave equation in a magneto-elastic circular rod, which represents the nonlinear interplay between dispersion and longitudinal wave velocity depending on the rod's material and geometry. The time-fractional order is used in the standpoint of conformable derivative. Comprehensive and descriptive waveform solutions, including kink-shaped, bell-shaped, and bright bell-shaped solitons, are obtained. The produced soliton solutions are advanced, unique, developed, and crucial. To demonstrate the physical appearance of the obtained solutions, 2D, 3D, and contour graphs of some of the obtained solutions are plotted. The extracted solutions demonstrate the physical significance of the model and express the pressure and electrostatic potential for the longitudinal wave equation and can be used to elucidate more complicated nonlinear models of classical and fractional order. The obtained results are helpful in finding the amplitude of tsunami waves which is of great interest to researchers in the field of ocean engineering. If a tsunami extends across a large area, it becomes a manifestation of solitons. The comparison of the obtained solutions is also given in the form of remarks 1 and 2 which shows the novelty of our work. [ABSTRACT FROM AUTHOR]

This paper investigates dynamic results of a small-scale-dependent panel subjected to a combination of mechanical, electrical, and magnetic loads using the shear defamation theory. Modified couple stress theory (MCST) is used for accounting small-scale effects in small sizes. Governing equations of motion are derived based on Hamilton's principle in the cylindrical coordinate system. The micro panel is composed of an elastic core integrated with two piezoelectric/piezomagnetic layers at top and bottom. Microlength scale parameter is included in the couple stress tensor and symmetric curvature tensor to capture size dependency. The analytical solution is applied for the solution of the motion equations. The extended parametric results are provided to show natural frequencies in terms of main significant input parameters such as initial electric/magnetic loads, span angle, length to thickness, radius to thickness, and length to radius ratio. Furthermore, the effect of higher mode numbers along the axial and circumferential directions is studied on the responses. The numerical results indicate that the natural frequencies are increased with an increase in initial magnetic potential and a decrease in initial electric potential. [ABSTRACT FROM AUTHOR]

A micromechanical model for the analysis of structurally periodic flexoelectric plates with periodically varying thickness is developed on the basis of asymptotic homogenization. The period of thickness variation is small and comparable to the plate thickness; accordingly, the plate is usually referred to as having a "rapidly varying thickness." The stipulation for rapidly varying thickness is important because it is envisioned that the developed model can be applied to a broad range of thin plates, both stratified as well as plates endowed with an arbitrary distribution of reinforcements attached to the surface or embedded within the plate. The microscopic problem is implemented in two steps pertaining, respectively, to first- and second-gradient asymptotic homogenization. Each level of homogenization culminates in its own set of unit cell problems from which the effective coefficients of the homogenized structure can eventually be obtained. These effective coefficients couple the force and moment resultants as well as the averaged electric displacement with the first and second gradients of the macroscopic displacement and electric potential. Once the effective coefficients are obtained, the macroscopic problem is invoked, which provides a set of four differential equations from which the macroscopic variables of mechanical displacement and electric potential can be obtained. The model is illustrated by means of laminated flexoelectric composites as well as simple rib-reinforced plates. It is shown that in the limiting case of a thin, purely elastic plate, the derived model converges to the familiar classical plate model. [ABSTRACT FROM AUTHOR]

The presence of a substantial short‐circuit current generates a large electromagnetic repulsive force. The energy of such a short‐circuit current increases the likelihood of equipment damage. Furthermore, the occurrence of short‐circuits disrupts the stable supply of electric power. When a short‐circuit occurs in a distribution line, short‐circuit point identification is realized based on information such as overcurrent indicators and equipment damage caused by the short‐circuit. However, there is no established method for promptly pinpointing the short‐circuit location. Therefore, this study proposes a short‐circuit point estimation method for distribution lines using smart‐meters; whose performance is anticipated to improve in the future. The proposed method involved using smart‐meter voltage measurements to measure and determine the changes in the voltage drop slope, caused by the distribution‐substation short‐circuit currents and load currents, from the short‐circuit location to the end point. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

4-(2-amino-2-oxoethyl) phenyl 4-methylbenzenesulfonate (APMBS), a novel compound, has been synthesized and characterized by spectro-analytical techniques. X-ray diffraction data reveals it crystallizes in the triclinic crystal system with space group P 1 ¯ . The structure is stabilized through strong N–H⋯O, weak C–H⋯O and C–H⋯π hydrogen bond interactions yielding a supramolecular structure. The N1A–H1AA⋯O4A, C4–H4⋯O3, and C14–H14⋯Cg1 (Ring: C8–C13) interactions link the molecules into dimers, while the interaction C9-H9–O2 results in the formation of a molecular chain along the a-axis. The optimized structural geometry, by and large, as calculated using DFT and HF techniques is in conformity with the corresponding X-ray data. The DFT computation further aid in the follow up investigations including frontier molecular orbitals (FMOs), density of states (DOS), atomic charges, and molecular electrostatic potential surface (MEP). For a comprehensive description of various molecular intersections, Hirsheld surface and fingerprint plots analysis has been reported, besides the combined atoms-in-molecules (QTAIM) and reduced density gradient (RDG) analysis. Docking studies have been performed against the target protein Tubulin-Colchicine: Stathmin-Like Domain Complex. [ABSTRACT FROM AUTHOR]

This research focuses on the importance of maintaining generator output voltage stabilization using automatic voltage regulator (AVR), especially in dealing with load impacts and environmental changes. Through the implementation of internet of things (IoT), this system can be controlled and monitored remotely, enabling real-time monitoring without physical presence at the generator location. The main objective of this research is to increase energy efficiency by optimizing generator operation. System development methods include design, prototyping and testing stages. Test results show that the automatic voltage regulator is effective in maintaining a stable output voltage of around 220 V, even though the current varies according to the existing load. The power produced ranges from 23 to 670 W, with a power factor between 0.7 and 1. Despite a slight voltage drop to 217 V, the power factor increases to 0.93. The system uses NodeMCU to send data to Blynk and Google Spreadsheets servers, as well as servo motors and PZEM-004T sensors for control and monitoring. Overall, this research shows that the internet of things-based automatic voltage regulator system is effective in maintaining stability and increasing generator operational efficiency, with the ability to manage voltage, current, power, and power factor efficiently. [ABSTRACT FROM AUTHOR]

In this work, the planar, electric, double-layer structures of non-polarizable electrodes in electrolyte solutions are studied with Gaussian field theory. A response function with two Yukawa functions is used to capture the electrostatic response of the electrolyte solution, from which the modified response function in the planar symmetry is derived analytically. The modified response function is further used to evaluate the induced charge density and the electrostatic potential near an electrode. The Gaussian field theory, combined with a two-Yukawa response function, can reproduce the oscillatory decay behavior of the electric potentials in concentrated electrolyte solutions. When the exact sum rules for the bulk electrolyte solutions and the electric double layers are used as constraints to determine the parameters of the response function, the Gaussian field theory could at least partly capture the nonlinear response effect of the surface charge density. Comparison with results for a planar electrode with fixed surface charge densities from molecular simulations demonstrates the validity of Gaussian field theory. [ABSTRACT FROM AUTHOR]

We present the coupling of two frameworks—the pseudo-open boundary simulation method known as constant potential molecular dynamics simulations (CμMD), combined with quantum mechanics/molecular dynamics (QMMD) calculations—to describe the properties of graphene electrodes in contact with electrolytes. The resulting CμQMMD model was then applied to three ionic solutions (LiCl, NaCl, and KCl in water) at bulk solution concentrations ranging from 0.5 M to 6 M in contact with a charged graphene electrode. The new approach we are describing here provides a simulation protocol to control the concentration of electrolyte solutions while including the effects of a fully polarizable electrode surface. Thanks to this coupling, we are able to accurately model both the electrode and solution side of the double layer and provide a thorough analysis of the properties of electrolytes at charged interfaces, such as the screening ability of the electrolyte and the electrostatic potential profile. We also report the calculation of the integral electrochemical double layer capacitance in the whole range of concentrations analyzed for each ionic species, while the quantum mechanical simulations provide access to the differential and integral quantum capacitance. We highlight how subtle features, such as the adsorption of potassium graphene or the tendency of the ions to form clusters contribute to the ability of graphene to store charge, and suggest implications for desalination. [ABSTRACT FROM AUTHOR]

We report the resonance-enhanced two-photon ionization combined with various detection approaches and quantum chemical calculations of biologically relevant neurotransmitter prototypes, the most stable conformer of 2-phenylethylamine (PEA), and its monohydrate, PEA-H2O, to reveal the possible interactions between the phenyl ring and amino group in the neutral and ionic species. Extracting the ionization energies (IEs) and appearance energy was achieved by measuring the photoionization and photodissociation efficiency curves of the PEA parent and photofragment ions, together with velocity and kinetic energy-broadened spatial map images of photoelectrons. We obtained coinciding upper bounds for the IEs for PEA and PEA-H2O of 8.63 ± 0.03 and 8.62 ± 0.04 eV, within the range predicted by quantum calculations. The computed electrostatic potential maps show charge separation, corresponding to a negative charge on phenyl and a positive charge on the ethylamino side chain in the neutral PEA and its monohydrate; in the cations, the charge distributions naturally become positive. The significant changes in geometries upon ionization include switching of the amino group orientation from pyramidal to nearly planar in the monomer but not in the monohydrate, lengthening of the N–H⋯π hydrogen bond (HB) in both species, Cα–Cβ bond in the side chain of the PEA+ monomer, and the intermolecular O–H⋯N HB in PEA-H2O cations, leading to distinct exit channels. [ABSTRACT FROM AUTHOR]

Field electron emission from nanometer-scale objects deviates from the predictions of the classical emission theory as both the electrostatic potential curves within the tunneling region and the image potential deviates from the planar one. This impels the inclusion of additional correction terms in the potential barrier. At the apex of a tip-like rotationally symmetric surface, these terms are proportional to the (single) local emitter curvature. The present paper generalizes this relation, showing that for any emitter geometry, the coefficient of the correction terms is given by the mean curvature, i.e., the average of the two principal curvatures. [ABSTRACT FROM AUTHOR]

Rock failure can cause serious geological disasters, and the non-extensive statistical features of electric potential (EP) are expected to provide valuable information for disaster prediction. In this paper, the uniaxial compression experiments with EP monitoring were carried out on fine sandstone, marble and granite samples under four displacement rates. The Tsallis entropy q value of EPs is used to analyze the self-organization evolution of rock failure. Then the influence of displacement rate and rock type on q value are explored by mineral structure and fracture modes. A self-organized critical prediction method with q value is proposed. The results show that the probability density function (PDF) of EPs follows the q-Gaussian distribution. The displacement rate is positively correlated with q value. With the displacement rate increasing, the fracture mode changes, the damage degree intensifies, and the microcrack network becomes denser. The influence of rock type on q value is related to the burst intensity of energy release and the crack fracture mode. The q value of EPs can be used as an effective prediction index for rock failure like b value of acoustic emission (AE). The results provide useful reference and method for the monitoring and early warning of geological disasters.

Abstract One crucial objective of this article is to present simplified and accurate approaches to study the current distribution and ground surface potential around the area surrounding an earthed and isolated system in case of a line‐to‐earth fault. The present study is done in the case of uniform and two‐layer soils. Suggested models for calculating the distribution of the earth's surface current density, step, and touch voltages in grounded and isolated systems are presented, discussed, and adapted. The contact and arc resistances of line to ground faulty conductors are considered. Rods and/or grounding grids usually do grounded systems. The impact of both step and touch potentials and current density are investigated in this article. The methods of the calculations are based on the electrical concepts, the charge simulation method, and the imaging procedure for the grounding system. The suggested method can be considered a novel and simple technique for calculating the current distributions of the ground surface during line to ground fault. The results agree with those obtained by others, with the advantage of the proposed algorithm for its ease of application and simplicity. 3‐D dimensions’ contours of the current density and the electric potential on the earth surface around the faulty point are presented in case of homogeneous and two layers’ soil. Finally, this article's novelty is to devise a method for calculating the step and touch potentials and current density around the point of contact of the conductor carrying the electric voltages in the event of faults occurring in the electrical network, whether the network is grounded or isolated. Such faults of electrical networks may cause human hazards.

Multinuclear (di/tri) copper(II) complexes bridged through hydroxyl groups are very interesting coordination complexes owing to their potential applications in various fields. In this work, three novel dinuclear (μ-hydroxo)-bridged copper(II) complexes in the crystal form, namely, [Cu2(3,5-DIFLB)2(H2tea)2](H2O) (1), [Cu2(4-ClB)2(H2tea)2](H2O) (2), and [Cu2(4-ETHB)2(H2tea)2](H2O)2 (3) (where DIFLB = difluorobenzoate, CLB = chlorobenzoate, ETHB = ethoxybenzoate, and H3tea = triethanolamine), were isolated at room temperature using methanol and water in a 4 : 1 v/v ratio as a solvent. Furthermore, all three complexes (1–3) were characterised using spectroscopic (UV-vis, DRS, and FT-IR), electrochemical (CV) and single-crystal X-ray diffraction techniques. Structural insights gained by packing analysis revealed the role of steric constraints of substituents and various non-covalent interactions in lattice stabilization, which were indeed supported by theoretical and molecular electrostatic potential illustrations. Hirshfeld surface analysis provided quantitative verification about various non-covalent interactions (interatomic contacts) involved in the packing of molecules. Interestingly, as a potential application, complexes 1–3 all exhibited remarkable visible light-mediated photo-Fenton degradation of approximately 98% for 50 ppm concentration of organic dyes (fuchsin basic (FB) and methyl orange (MO)) in 90 minutes with the optimized conditions of 1 mg mL−1 of dye solution. In all the cases, dye degradation by these materials was ascribed to the symbiotic relations among the molecular structures of complexes 1–3, which were endowed with various electron-withdrawing and electron-releasing substituents and ionic strength, with respect to the structure, shape and interacting patterns of dye molecules. The adsorption mechanism indicates that various weak interactions between the donor and acceptor groups of complexes and dyes, such as electrostatic, hydrogen bonding, and direct coordination to metal sites, play a crucial role, which is confirmed by molecular dynamics (MD) simulations. Theoretical studies by DFT-based descriptors, molecular electrostatic potentials, and band gaps provided deep insights into various electronic and reactivity parameters. For subsequent processes of dye degradation, complexes 1–3 were stable and recoverable. The successful integration of experimental and theoretical approaches sheds light on copper-based dinuclear stable coordination complexes, showcasing a significant step towards the development of novel heterogeneous photo-Fenton catalysts. [ABSTRACT FROM AUTHOR]

Pulsars often display systematic variations in the position and/or intensity of the subpulses, the components that comprise each single pulse. Although the drift of these subpulses was observed in the early years of pulsar research, and their potential for understanding the elusive emission mechanism was quickly recognized, there is still no consensus on the cause of the drift. We explore the electrodynamics of two recently proposed or refined drift models: one where plasma lags behind corotation, connecting the drift with the rotational pole; and another where plasma drifts around the electric potential extremum of the polar cap. Generally, these are different locations, resulting in different drift behaviours, that can be tested with observations. In this study, however, we specifically examine these models in the axisymmetric case, where the physics is well understood. This approach seems counter-intuitive as both models then predict similar large-scale plasma drift. However, it allows us to show, by studying conditions within the sparks for both models, that the lagging behind corotation model is inconsistent with Faraday's law. The modified carousel (MC) model, where plasma drifts around the electric potential extremum, not only aligns with Faraday's law, but also provides a future direction for developing a comprehensive model of plasma generation in the polar cap region. Unlike previous models, which considered the drift only inside the discharging regions, the MC model reveals that the electric field between the discharges is not completely screened, and plasma drifts there – a paradigm shift for the drifting subpulse phenomenon. [ABSTRACT FROM AUTHOR]