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Two novel potassium pentazolate frameworks KN5·1.5CH3COOK (1) and KN5·3CF3COOK (2) were achieved by changing the content and type of K-carboxylates. All the compounds were characterized via infrared (IR), single-crystal X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. 1 exhibited two unique nanocages featuring KN5 and CH3COOK. 2 with a high density (2.097 g cm−3) was constructed by replacing the H atoms of 1 with the most electronegative F atoms. The F atoms of 2 form channels that constituted a peculiar porous structure. The electronegativity, atomic charge, and electrostatic potential were further analyzed for the differences between the two frameworks and explained the reasons for the constitution. This work demonstrates that it is possible to regulate the crystal structure and density through appropriate additives. [ABSTRACT FROM AUTHOR]

Within the scope of this study, a total of eight new NLOphores of the D‐π‐A‐π‐D type have been synthesized. This was achieved by applying click‐type [2+2] cycloaddition‐retroelectrocyclization reactions of unsymmetrical 1,3‐diynes with well‐known electron‐deficient alkenes, TCNE, and TCNQ. Furthermore, essential insights into the optical properties of the synthesized NLOphores were obtained from comparisons with four model compounds synthesized separately within this study. The thermal stability of the NLOphores was assessed through thermal gravimetric analysis (TGA). NLOphores synthesized using two distinct electron‐deficient alkenes exhibit low energy absorption bands covering most of the visible region with λmax values ranging from 466 nm to 723 nm. Theoretical studies, including time–dependent density functional theory (TD‐DFT) investigations, frontier orbital visualizations, and electrostatic potential maps, have been utilized to further investigate the intramolecular charge transfer properties of chromophores. The NLO responses of the chromophores were determined through DFT calculations. It is worth noting that the average polarizability and first hyperpolarizability values (α(tot)=106.392–159.709×10−24 esu; β(tot)=387.552–417.359×10−30 esu) obtained from these calculations show significant promise compared to literature data. [ABSTRACT FROM AUTHOR]

Virtual screening of a library of 329 flavonoids obtained from the NPACT database was performed to find out potential novel HDAC2 inhibitors. Eleven out of 329 selected flavonoids were screened based on molecular docking studies, as they have higher binding affinities than the standard drugs vorinostat and panobinostat. All screened compounds occupying the catalytic site of HDAC2 showed important molecular interaction with Zn2+ and other important amino acids in the binding pocket. The screened compounds were validated using ADMET filtration and bioactivity prediction from which we obtained six compounds, NPACT00270, NPACT00676, NPACT00700, NPACT001008, NPACT001054, and NPACT001407, which were analyzed using DFT studies. DFT studies were performed for all six screened flavonoids. In DFT studies, three flavonoids, NPACT00700, NPACT001008, and NPACT001407, were found to be better based on HOMO–LUMO and molecular electrostatic potential (MEP) analyses. Furthermore, MD simulations were performed for 100 ns for the three compounds. In the MD analysis, NPACT001407 was found to be more stable in the active site of HDAC2 as zinc formed a coordination bond with ASP181, HIS183, ASP269, and GLY305, along with two hydroxyl groups of the ligand. Our findings reveal that these flavonoids can interact as ligands with the active site of HDAC2. Because of the absence of a hydroxamate group in flavonoids, there are no possibilities for the formation of isocyanate. This suggests that the major drawback of current HDACs inhibitors may be solved. Further experimental validation is needed to understand the selectivity of flavonoids as HDAC2 inhibitors. [ABSTRACT FROM AUTHOR]

Permanent magnet (PM) motors are gaining prominence in subsea applications such as drilling, pumping, and boosting for oil and natural gas extraction. These motors are gradually replacing traditional induction motors. However, starting and operating PM motors at low speeds under heavy loads poses significant challenges. This is because of unknown initial rotor positions and resistive voltage drops due to the presence of a sinewave filter, transformer, and long cable. An unknown rotor position may result in temporary reverse speed, which may cause a loss of synchronism; therefore, initial rotor position estimation is preferable. Additionally, addressing the voltage drop issue requires careful voltage compensation to avoid transformer core saturation. In this paper, an enhanced V / H z starting of a PM motor is proposed with initial position detection (IPD) and voltage compensation to start the motor reliably with a heavy load. The proposed control method is verified with controller hardware in the loop (C-HIL) real-time simulation using a Typhoon HIL-604 emulator and a Texas Instruments TMS320F28335 digital signal processor (DSP) control card. [ABSTRACT FROM AUTHOR]

The contagiousness of SARS-CoV-2 β-coronavirus is determined by the virus–receptor electrostatic association of its positively charged spike (S) protein with the negatively charged angiotensin converting enzyme-2 (ACE2 receptor) of the epithelial cells. If some mutations occur, the electrostatic potential on the surface of the receptor-binding domain (RBD) could be altered, and the S-ACE2 association could become stronger or weaker. The aim of the current research is to investigate whether point mutations can noticeably alter the electrostatic potential on the RBD and the 3D stability of the S1-subunit of the S-protein. For this purpose, 15 mutants with different hydrophilicity and electric charge (positive, negative, or uncharged) of the substituted and substituting amino acid residues, located on the RBD at the S1-ACE2 interface, are selected, and the 3D structure of the S1-subunit is reconstructed on the base of the crystallographic structure of the S-protein of the wild-type strain and the amino acid sequence of the unfolded polypeptide chain of the mutants. Then, the Gibbs free energy of folding, isoelectric point, and pH-dependent surface electrostatic potential of the S1-subunit are computed using programs for protein electrostatics. The results show alterations in the local electrostatic potential in the vicinity of the mutant amino acid residue, which can influence the S-ACE2 association. This approach allows prediction of the relative infectivity, transmissibility, and contagiousness (at equal social immune status) of new SARS-CoV-2 mutants by reconstruction of the 3D structure of the S1-subunit and calculation of the surface electrostatic potential. [ABSTRACT FROM AUTHOR]

This study emphasizes the synthesis of a novel series of 1,2,3-triazolo-benzoquinoline-3-carbonitriles by using Cu(I)-catalyzed azide–alkyne cycloaddition known as the click reaction. The reaction of novel acetylenic aryl-benzoquinoline-3-carbonitriles 7–12 with 1-azido-2,5-dimethoxy-4-nitrobenzene 13 afforded the corresponding 1,2,3-triazolo-benzoquinoline-3-carbonitriles 14–19 in good yields. The desired products were examined against different tumor cells such as the human colon (HCT-116), hepatocellular carcinoma (HepG2), human breast adenocarcinoma (MCF-7) and one human healthy cell line (BJ-1) using the LDH assay. Generally, the five compounds (11, 10, 9, 12 and 15, respectively) can be considered good colon anticancer drug candidates as their cytotoxic activities on the colon cancer cells are higher than their cytotoxic activities on the normal cells. In the case of HepG2 human liver cancer cells, compounds 16, 12 and 9 have more potent cytotoxic activities relative to doxorubicin as the standard reference. Supporting the experimental antiproliferative IC50 of the compounds tested against the cancer cell line, the molecular electrostatic potential (MEP) distribution and frontier molecular orbitals (FMOs) of all compounds have been calculated in the ground state theoretically by the DFT/B3LYP method using the 6-31G(d) basis set. Compounds 10, 15 and 19 showed a chemical softness value of 14.59 eV−1 higher than those of all of the compounds. The highest values of the electrophilicity index were observed in compounds 17, 10, 16 and 15. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) system parameters are always non-linear due to variable environmental conditions. The Maximum power point tracking (MPPT) is difficult under multiple uncertainties, disruptions and the occurrence of time-varying stochastic conditions. Therefore, Passivity based Fractional order Sliding-Mode controller (PBSMC) is proposed to examine and develop a storage function in error tracking for PV power and direct voltage in this research work. A unique sliding surface for Fractional Order Sliding Mode Control (FOSMC) framework is proposed and its stability and finite time convergence is proved by implementing Lyapunov stability method. An additional input of sliding mode control (SMC) is also added to a passive system to boost the controller performance by removing the rapid uncertainties and disturbances. Therefore, PBSMC, along with globally consistent control efficiency under varying operating conditions is implemented with enhanced system damping and substantial robustness. The novelty of the proposed technique lies in a unique sliding surface for FOSMC framework based on Riemann Liouville (R-L) fractional calculus. Results have shown that the proposed control technique reduces the tracking error in PV output power, under variable irradiance conditions, by 81%, compared to fractional order proportional integral derivative (FOPID) controller. It is reduced by 39%, when compared to passivity based control (PBC) and 28%, when compared to passivity based FOPID (EPBFOPID). The proposed technique led to the least total harmonic distortion in the grid side voltage and current. The tracking time of PV output power is 0.025 seconds in PBSMC under varying solar irradiance, however FOPID, PBC, EPBFOPID, have failed to converge fully. Similarly the dc link voltage has tracked the reference voltage in 0.05 seconds however the rest of the methods either could not converge, or converged after significant amount of time. During solar irradiance and temperature change, the photovoltaic output power has converged in 0.018 seconds using PBSMC, however remaining methods failed to converge or track fully and the dc link voltage has minimum tracking error due to PBSMC as compared to the other methods. Furthermore, the photovoltaic output power converges to the reference power in 0.1 seconds in power grid voltage drop, whereas other methods failed to converge fully. In addition power is also injected from the PV inverter into the grid at unity power factor. [ABSTRACT FROM AUTHOR]

Developing a fluidic platform that combines high-throughput with reconfigurability is essential for a wide range of cutting-edge applications, but achieving both capabilities simultaneously remains a significant challenge. Herein, we propose a novel and unique method for droplet manipulation via drawing surface charge graphics on electrode-free papers in a contactless way. We find that opposite charge graphics can be written and retained on the surface layer of porous insulating paper by a controlled charge depositing method. The retained charge graphics result in high-resolution patterning of electrostatic potential wells (EPWs) on the hydrophobic porous surface, allowing for digital and high-throughput droplet handling. Since the charge graphics can be written/projected dynamically and simultaneously in large areas, allowing for on-demand and real-time reconfiguration of EPWs, we are able to develop a charge-graphic fluidic platform with both high reconfigurability and high throughput. The advantages and application potential of the platform have been demonstrated in chemical detection and dynamically controllable fluidic networks. [ABSTRACT FROM AUTHOR]

The water affinity on [60]fullerenols was found to be governed by surface electrostatic potential while water aggregation is initiated by the hydroxy groups attached on the carbon surface. The molecular water adsorption at the internal sphere caused a significnat inhibition of water adsorption at the external carbon surface. [ABSTRACT FROM AUTHOR]

Future transportation will replace the current mechanical combustible engines with chargeable electric vehicles (EVs). The DC-Dc boost converter is an essential part of such systems that not only helps to generate the required level but also helps to regulate the load voltage. In conventional boost converter topologies, their gain, switching losses, and high voltage stress across switches are the main reason for limiting the output power. Coupled inductor-based isolated converters increase the system weight and cost. Therefore, in this paper, a transformerless adjustable gain and non-isolated DC-DC boost converter with multi-port flexible power supply, reduced switch voltage stress, and considerable good range efficiency is proposed. The proposed converter is tested with the 100 W resistive load to test the desired characteristics. [ABSTRACT FROM AUTHOR]

In the current research, a new therapeutically active ethyl-4-(2,4-methoxyphenyl)-1,2,3,4-tetrahydro-6-methyl-2-thioxopyrimidine-5-carboxylate (DMPC) prepared by the Biginelli reaction was found to possess effective antioxidant and thrombolytic activities. The geometry of the DMPC was confirmed by the single crystal X-ray diffraction analysis and DFT studies carried out by B3LYP6-311++G (d,p) method and the results have been compared with the actual values. The Mulliken charge distribution, molecular electrostatic potential (MEP) surface, HOMO and LUMO of the DMPC were calculated by victimization a similar level theory. NLO of the DMPC was studied from the optimized geometry. The drug receptor interactions of the molecule were studied by molecular docking using auto dock 4.2. [ABSTRACT FROM AUTHOR]

In this study, ten novel disazo dyes based on aminothiazoles (4a-e, 5a-e) were synthesized in the first section. By using their 1H-NMR, FT-IR, and UV-Vis spectra, these synthesized dyes' structures were verified. In the second section, the density functional theory (DFT) was used to calculate the molecular geometry, vibrational frequency and molecular electrostatic potential (MEP) diagram in the ground state using the B3LYP level and the 6-311 G(d,p) basis set. UV-vis data were obtained using the Gaussian 09 TD-DFT Cam-B3LYP 6-311 G ++ (d,p) basis set. To explore the chemical shift values, the gauge independent atomic orbital (GIAO) approach was used. Time-dependent DFT (TD-DFT) approach was used to determine the HOMO–LUMO calculations. As a consequence of our research, it was found that the experimental values and the computational spectroscopic values of the synthesized disazo compounds were consistent. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effect of NaOH concentration and immersion time on the activation of carbon from the oil palm frond, specifically focussing on the surface morphology and characteristics as electrodes for biobattery application. Carbonization and NaOH activation are carried out at 0.5, 1, 1.5, 2, and 2.5 M at different immersion times of 12, 18, 24, 30, and 36 hour. Moreover, the activated carbon was analyzed with a scanning electron microscope to observe the morphology, and the Brunauer–Emett–Teller (method was used to measure the surface area of activated carbon). Furthermore, another outcome of this study is the development of a prototype biobattery. At 1 M, the optimal concentration of NaOH was observed, producing the highest surface area of 336.493 m2g−1 and an electric potential of 0.653 V. On the other hand, the optimal immersion time was 30 hour with the highest surface area of 396 808 m2g−1 and an electric potential of 0.902 V. [ABSTRACT FROM AUTHOR]

The current state of affairs requires a highly sensitive, accurate, fast, and power-efficient biosensor. The proposed work investigates the performance of a Germanium-based dielectric-modulated junctionless charge plasma tunnel field-effect transistor (Ge-DMJ-CPTFET) as a label-free biosensor. The nanogap cavity is formed by removing gate oxide material from underneath the source electrode. The target biomolecules are modeled inside the nanogap cavity. The biomolecules are identified using their hereditary properties, such as charge density and dielectric constant. The Dielectric Modulation technique and Charge-Plasma concept have been used to investigate the biomolecules immobilized in the nanogap cavity. Germanium exhibits high carrier mobility and superior tunneling characteristics compared to silicon, allowing for improved charge transport across the device channels. The low energy-band gap of Ge helps to reduce tunneling width and increase drain current. The performance of the proposed device is investigated in terms of band energy, electric field, and electric potential at different values of dielectric constant and charge densities of the biomolecules. Moreover, the Sensitivity of the proposed device is investigated for both neutral and charged biomolecules. Along with a label-free biosensor, Ge-DMJ-CPTFET is free from random dopant variations, low thermal budget, and is compatibility with silicon technology. [ABSTRACT FROM AUTHOR]

Electrospray thrusters employ ionization in the liquid phase to produce and propel streams of molecular ions or highly charged droplets at significant velocities. In this study, we developed a novel annular slit-type emitter for electrospray and investigated its operational modes under varying applied potentials in both open atmosphere and vacuum conditions. To assess the performance of the annular slit-type emitter in comparison to the conventional capillary-type emitter, benchtop electrospray experiments were conducted using water and glycerin as working fluids for both emitter types. The study examined the formation of the Taylor cone, cone-to-jet transition, stable jet, whipping jet, and multi-jet, along with their dependence on fluid viscosity and electric potential for both emitter designs. Clear distinctions in hydrodynamic mode, drop-to-cone mode, and cone-to-jet transition mode were observed between the two emitters. As the electric potential increased, the capillary-type emitter exhibited a whipping and pulsating water jet, while glycerin displayed a steady tilted jet. In contrast, the annular slit-type emitter demonstrated a pulsating water jet followed by a distinctive dripping mode at higher electric potentials, while glycerin formed multiple steady jets around the annular slit. Notably, the annular slit-type emitter, when subjected to an 18.5 kV potential, produced seven electrospray jets for glycerin, a phenomenon attributed to the novel design of the emitter and the viscosity of glycerin enabling the generation of multiple cone-jets at a specific electrostatic potential around the slit peripheral meniscus. Vacuum chamber tests of the annular-type emitter using liquid indium as an ion source at 1×10−5 Torr revealed an ion-current density of 0.3 mA/mm, resulting in a thrust of 290 μN. [ABSTRACT FROM AUTHOR]

The electron density distribution (EDD) of a plant cyclic nonapeptide of orbitide type was studied. Crystal X-ray diffraction data was obtained from the Cambridge Structural Database (CSD) and refitted using scattering factors of the invariom library, thereby providing aspherical electron density. Bond topological, atomic properties and molecular surfaces (electrostatic potential and Hirshfeld surfaces) were derived. The partial double bond character of the peptide bond was confirmed by the ellipticity ε = 0.25. For eight N–H⋯O hydrogen bonds, atomic charges of contributing atoms differ depending on the type of the accepting oxygen atom. Atomic charge differences between negative main and positive side chains of this nonapeptide result in characteristic features of the electrostatic potential, which shows a positive isosurface around the molecule leading to repulsive interactions in the solid state structure. Weak intermolecular interactions are indicated by insignificant ED concentrations on the Hirshfeld surface except for weak signals at sites of intermolecular N–H⋯O and C–H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The local scaling symmetry of the Lagrange density is exploited to investigate the myriad electro-mechanical coupling effects observed in the elastic dielectrics. In contrast to most known flexoelectricity theories, this approach has also explicated on the geometric underpinnings of the induced polarization and electric potential. Due to the inhomogeneous scaling of the metric, the invariance of the Lagrange density will be lost. To restore the gauge invariance of the Lagrange density, we introduce the notion of minimal replacement, viz., define a gauge covariant operator in place of the ordinary partial derivative. Minimal replacement introduces gauge compensating one form field. We relate the exact part of the gauge compensating one form field with electric potential. However, the gauge compensating one form field's anti-exact part is correlated with the electric polarization vector. We constructed different components of the gauge invariant energy density using the geometric objects like scale invariant gauge curvature. We appropriately contracted the skew symmetric gauge curvature tensor with the metric to construct the scale invariant energy associated with the gauge field. Finally, we derive the governing coupled equations employing Hamilton's principle. In order to assess how the theory performs, we carry out a few numerical simulations and validation. Model prediction of the pressurized flexoelectric disk with a central hole shows good agreement with the analytical solution. We also investigated flexoelectric cantilever beam subjected to a point load and different earthing conditions. Explorations of this kind of coupling may have notable implications in many industrial and laboratory applications. • Studied electro-mechanical coupling in dielectrics using the scaling symmetry. • Explored geometric underpinnings of induced polarization and electric potential. • Also recovered elastic Lagrangian assuming Euclidean manifold with gauge fixing. • Correspondence with Mindlin's polarization gradient theory for dielectrics. • This kind of coupling may have notable implications in many applications. [ABSTRACT FROM AUTHOR]

• A novel piezoelectric semiconductor cylindrical shell is proposed. • The principle of virtual work is applied for the governing equations. • 2D behaviors in static bending and forced vibration are considered. • Mechanical displacements and electric potentials are sensitive to the doping level. • New structure and analytical solutions are helpful for sensing and energy harvesting. This paper examines the mechanically induced electric potential and charge redistribution in a piezoelectric semiconductor cylindrical shell employing first-order shear deformation theory. The two-dimensional governing equations and corresponding boundary conditions are simultaneously derived through a principle of virtual work method and the fundamental lemma of the calculus of variation. For the application of electronic devices, static bending and forced vibration analyses of an open cylindrical shell under locally distributed normal forces are analytically solved with the derived theoretical model. The effects of doping level on electric potentials and mechanical displacements are presented. An interesting result shows that doping levels can alter the peak position of the zeroth-order electric potential. In addition, the first three order natural frequencies of the shell under time-harmonic load are identified, and the doping level is found to have an inhibiting effect on the first natural frequency. All the numerical results are beneficial for optimizing the design and performance of cylindrical shell-shaped sensors and energy harvesters. [ABSTRACT FROM AUTHOR]

Electrodes are used to measure a potential difference between two points. In geophysical and geotechnical applications they are often in the form of non‐polarizable porous‐pot electrodes. Here we describe the design, construction, and testing of modular and refillable electrodes, which facilitates repair as the electrodes degrade over time. We use a chemical composition based on a metal in contact with an over‐saturated electrolyte that consists of a salt of that metal and an auxiliary salt. We compare characteristics when the electrolyte is stabilized in a clay or not, and with various states of ceramic porous plugs and two types of wood plugs. Next, we assess the long‐term stability (more than 1 month), noise (periods of 1 s to 1 hr), and temperature sensitivity of different types of electrodes. Electrodes with an electrolyte and clay formula showed lower noise (0.2–0.4 μV at periods of 1–120 s), greater long‐term stability (0.05–0.5 mV/month of smooth drift), and greater consistency between samples measured than those with no clay (noise and drift values up to four times larger). The effects from different porous plugs were negligible, with similar results for ceramic and wood types. The temperature sensitivity of the electric potential was assessed, from −3 to 35°C. All electrodes showed a temperature sensitivity of about −30 μV/°C. This is considered very low compared to some commercially available electrodes. Finally, continuous long‐term laboratory and field measurements of the potential highlight the application of the new electrodes. Key Points: Development of a modular, repairable, refillable porous‐pot electrode with an over‐saturated electrolyte, preferably stabilized in clayLong‐term measurements reveal (a) high stability, (b) smooth drift, <0.5 mV/month, and (c) low noise, 0.2–0.4 μV at a period of 1–120 sExperiments from −3 to 35°C determine a temperature sensitivity of the electric potential of about −30 μV/°C, which is considered low [ABSTRACT FROM AUTHOR]

Self-healing polymeric materials has created an extensive interest among researchers due to their autonomic healing ability and potential applications in wide range of industries. Herein, we report an intrinsic self-healing method, by using a novel isocyanate based self-healing curator for polyurethane formation which exhibits excellent self-healing capability via disulfide metathesis. Exchange of disulfide bonds between polymeric chains at the damaged area leads to self-healing. Density Functional Theory [DFT/B3LYP/6-311++G (d, p)] calculations were done to examine the optimized molecular geometry, vibrational frequencies, 1H and 13C NMR chemical shifts, HOMO–LUMO energies and molecular electrostatic potential (MEP) map of the compound. The theoretical results were also closely matched with the experimental data. The concept of self-healing-cum-curing agent in polyurethane matrix has not been explored so far. [ABSTRACT FROM AUTHOR]

This work introduces a solid-shell element with eight nodes for the bending behavior of structures embedded with piezoelectric layers using the FSDT theory. The mechanical degrees of freedom are coupled, through the constitutive equations, with the piezoelectric one considering the linear distribution of the electric potential along the piezoelectric face's thickness. In order to subdue shear and thickness locking, the Assumed Natural Strain (ANS) method as well as the Enhanced Assumed Strain (EAS) method are adopted. Bonding the external faces of shell structures with piezofaces accentuates the smart aspect of solid shells. The middle part of the structure is made of a Functionally Graded Material (FGM) with distributed pores along the thickness. The formulated finite element model is implemented to investigate the effects of some parameters on the bending response of solid shells such as the impact of various configurations of porous FGM, the power law index of FGM and some geometrical parameters of solid shell structures. [ABSTRACT FROM AUTHOR]

A relation between classical electrostatic fields and Shrödinger-like Hamiltonians is evidenced. Hence, supersymmetric quantum potentials analogous to classical electrostatic fields can be constructed. Proposing an ansatz for the electrostatic potential as the natural logarithm of a nodeless function, it is demonstrated that the electrostatic fields fulfil the Bernoulli equation associated to a second-order confluent supersymmetric transformation. By using the so-called confluent algorithm, it is possible, given a charge density, to find the corresponding electrostatic field as well as the supersymmetric potentials. Furthermore, the associated charge density and the electrostatic field profile of Schrödinger-like solvable potentials can be determined. [ABSTRACT FROM AUTHOR]

An electroencephalogram (EEG), recorded on the surface of the scalp, serves to characterize the distribution of electric potential during brain activity. This method finds extensive application in investigating brain functioning and diagnosing various diseases. Event-related potential (ERP) is employed to delineate visual, motor, and other activities through cross-trial averages. Despite its utility, interpreting the spatiotemporal dynamics in EEG data poses challenges, as they are inherently subject-specific and highly variable, particularly at the level of individual trials. Conventionally associated with oscillating brain sources, these dynamics raise questions regarding how these oscillations give rise to the observed dynamical regimes on the brain surface. In this study, we propose a model for spatiotemporal dynamics in EEG data using the Poisson equation, with the right-hand side corresponding to the oscillating brain sources. Through our analysis, we identify primary dynamical regimes based on factors such as the number of sources, their frequencies, and phases. Our numerical simulations, conducted in both 2D and 3D, revealed the presence of standing waves, rotating patterns, and symmetric regimes, mirroring observations in EEG data recorded during picture naming experiments. Notably, moving waves, indicative of spatial displacement in the potential distribution, manifested in the vicinity of brain sources, as was evident in both the simulations and experimental data. In summary, our findings support the conclusion that the brain source model aptly describes the spatiotemporal dynamics observed in EEG data. [ABSTRACT FROM AUTHOR]

Nowadays, the demand for electronics has increased, which requires some amount of input supply. This energy supply is now shifted from conventional to new techniques such as solar energy, wind energy and many other so-called free energies. Another type of free energy in an environment is sound energy; sometimes, it is referred to as noise. Hence, this article aims to convert this noise into electrical output to utilise it and drive small electronic applications. Nevertheless, the noise is uncomfortable for humans; hence, this experiment does not only convert energy but also reduces the noise amplitude. Here, the polyvinylidene difluoride (PVDF) piezoelectric element converts mechanical vibrations into electricity. It is employed in a foam block, and the sound source is placed at different heights of the foam block, just to analyse the output signal after sound impingement from different angles. Here, the maximum output peak of 80 mV is seen at 650 Hz and 82.9 dB. Likewise, different peaks of outputs have been observed. Also, noise reduction has been observed in this experiment; the maximum reduction of noise amplitude has occurred in the frequency range of 1100 Hz to 1200 Hz. [ABSTRACT FROM AUTHOR]

With the technological development of industrial automation, an increasing number of modern electronic components, which are very sensitive to voltage changes, are emerging in the distribution network as sensitive lodes. Enormous economic losses will be caused if voltage disturbance happens. Therefore, in this article, to support the voltage on these sensitive nodes in a targeted manner, an index denoted as vrc ~ is constructed to quantitatively describe the voltage recovery capability. Afterward, to satisfy the constraint of index vrc ~ , distributed wind turbines (DWTs) and distribution static compensators (D-STATCOMs) are optimized to the most beneficial capacities and locations, to provide the reactive power required by the sensitive nodes during voltage recovery process. The proposed mathematical model is relaxed from MINLP model into a second-order cone relaxation (SOCR) model and verified on IEEE 33-bus distribution network under scenarios with different vrc ~ values. The results prove that connecting sensitive loads to distribution network has large influences on the configuration scheme of DWTs and D-STATCOMs. Moreover, three algorithms named cuckoo search optimization(CSO), clustering cuckoo search optimization(CCSO) and Jaya are provided to compete with SOCR method in solving this mathematical model. Results show that SOCR method is superior than all the algorithms in robustness and effectiveness in terms of processing time and solution quality. [ABSTRACT FROM AUTHOR]

The fast-growing influence of grid-interfaced photovoltaic (PV) networks makes it necessary to adhere to grid-code (GC) regulations. These regulations mandate that PV systems inject active power both during and after the grid fault occurrence, as well as provide reactive current to the grid during voltage dips, in order to prevent power system stability concerns. In this context, two novel control schemes have been proposed in this paper for grid-connected photovoltaic networks that can support low-voltage ride-through (LVRT). The proposed control techniques have been demonstrated to be simple and efficient in the event of severe voltage dips, i.e., work up to a voltage drop of 90% of the nominal grid voltage. Our first approach involves an enhanced reactive current injection strategy that provides reactive power support to the power grid during voltage dips without any additional devices. The control structure is comprised of a voltage level estimator and a reactive current controller. The voltage level estimator obtains power grid voltage, while the reactive current controller computes active−reactive current commands. It is particularly noteworthy that the proposed scheme generates active current as much as possible according to the voltage dips and tracks the active current reference correctly, where conventional strategies fail to cope. The second control method for LVRT presented in this research work involves using hardware, specifically a crowbar. The use of a crowbar is the most straightforward method to provide support to the power system, bypassing over-current during voltage dips and keeping the current within the normal converter rating. The control strategies proposed in this paper are validated in MATLAB/Simulink under symmetrical and unsymmetrical severe voltage dips as well as grid voltage harmonics, and a detailed comparison study with a state-of-the-art PQ-based fault-ride-through controller has been conducted. [ABSTRACT FROM AUTHOR]

We consider a set of bipolar Euler–Poisson equations and study two asymptotic limiting processes. The first is the zero-electron-mass limit, which formally results in a nonlinear adiabatic electron system. In a second step, we analyze the combined zero-electron-mass and quasi-neutral limits, which together lead to the compressible Euler equations. Using the relative energy method, we rigorously justify these limiting processes for weak solutions of the two-species Euler–Poisson equations that dissipate energy, as well as for strong solutions of the limit systems that are bounded away from vacuum. This justification is valid in the regime of initial data for which strong solutions exist. To deal with the electric potential, in the first case we use elliptic theory, whereas in the second case we employ the theory of Riesz potentials and properties of the Neumann function. [ABSTRACT FROM AUTHOR]

This study focuses on analyzing a slanted lip-shaped crack within a thermoelectric plate that experiences both a temperature gradient and an electric potential gradient. Based on the electrically insulated and thermally permeable crack model, we derive analytical solutions for the thermoelectric field and the associated thermal stress field in the cracked thermoelectric material by employing the complex variable method. Subsequently, we evaluate the stress intensity factors at the tips of the lip-shaped crack. Under the impact of thermoelectric loading, both mode-I and mode-II stress intensity factors occur at the tips of a slanted lip-shaped crack. Numerical examples are provided to demonstrate the influence of crack width, crack angle and thermal conductivity of the filling medium on the stress intensity factors at the crack tip. [ABSTRACT FROM AUTHOR]

Electrophoresis facilitated cancer treatment has demonstrated experimental efficacy in enhancing drug delivery within vascularised tumours. However, the lack of realistic mathematical models with direct measurements in the context of electrochemotherapy poses a challenge. We investigate the impact of an applied electric potential on the flow of Darcian-type fluid occurring in two distinct phases: the tumour and healthy regions. We employ the asymptotic homogenisation technique, assuming that the macroscale of the tumour domain is larger than the microscale characterised by vessel heterogeneities. We retain information about the microstructure by encoding information in the homogenised coefficients. We take into account both vascularisation and the microscale variations of the leading order and fine scale electric potential. The resulting effective differential problem reads as a Darcy-type system of PDEs, where the flow is driven by an effective source. The novel model can be used to predict the effect of an applied electric field on cancerous biological tissues, paving a new way of improving current electrochemotherapy protocols. [ABSTRACT FROM AUTHOR]

Context: To explore the impact of OGs (OGs) on formaldehyde (HCHO) adsorption by modified activated carbon, this paper studied the influence of OGs on HCHO adsorption characteristics, varying the groups including ester, carboxyl, and hydroxyl. Employing density functional theory (DFT), the effects of various OGs on the structure of N-doped activated carbon through GGA-PBE exchange-correlation functionals by Materials Studio combined with Gaussian software. The types of weak interactions during the adsorption process were calculated by RDG, elucidating the mechanism through which the three OGs affect HCHO adsorption on N-doped activated carbon. The dynamic adsorption process of HCHO was simulated by molecular dynamics (MD). The influence and proportion of OGs on HCHO adsorption were subsequently analyzed using van der Waals and electrostatic interactions, determining differences in formaldehyde adsorption effects across OG types. The carboxyl group exhibits the most robust synergistic adsorption effect on the modified activated carbon. There is a notable alteration in the position and distribution of electrostatic potential extremes observed following carboxyl modification. The calculation results show that the adsorption energy of hydroxyl groups on modified activated carbon is the highest, at −5.07 kcal/mol, with a transfer charge of 0.014 e. Following the introduction of carboxyl groups, the proportion of electrostatic interactions escalated from the initial 24% to 38%. This study will provide new ideas for guiding the design of activated carbon for efficient adsorption of formaldehyde. Methods: The modified activated carbon fragments of three OGs were constructed by Materials Studio and Gaussian software, and the surface electrostatic potential polarity and area distribution, charge change, adsorption energy, and transferred charge of each molecular fragment were calculated. Moreover, cell models of OGs with the same dimensions were constructed to simulate the adsorption amount, heat of adsorption, interaction energy, radial distribution function, and hydrogen-bonding interactions for methane at room temperature and pressure. The results were consistent with the DFT simulations. [ABSTRACT FROM AUTHOR]

A finite element is developed for a piezoelectric beam theory whose displacement varies according to the Timoshenko assumption, and the electric potential varies quadratically through each piezoelectric patch thickness. The application of Gauss's law to patches in the sensing mode is treated as a constraint in order to eliminate electric degrees of freedom from the weak form of the problem and, thus, formulate a two-node element with the same degrees of freedom as its purely mechanical counterpart (i.e., two displacements and one rotation per node). As a result, the element can be easily included in any computer program by simply replacing the existing purely mechanical element with this piezoelectric one. Since the approximation space is the same as that of the general homogeneous solution of the piezoelectric beam theory, the element enjoys the superconvergence property and is completely free of locking. Simple numerical tests on linear static problems are presented to demonstrate the ability of the element to give exact nodal values for the displacements, rotations, and reactions, irrespective of the mechanical and electrical loadings applied and mesh used. Also, the ability of a postprocessing scheme, which is set up to recover the exact sensing voltages at the nodes, is demonstrated. The element is further employed in shape-control problems. [ABSTRACT FROM AUTHOR]

The newly synthesized heterocyclic chalcone derivatives 3‐(5‐methyl furan‐2‐yl)‐1‐phenyl prop‐2‐en‐1‐one (MFPP) and 1‐(4‐chlorophenyl)‐3‐(5‐methylfuran‐2‐yl) prop‐2‐en‐1‐one (CPMFP) are recently being recognized for their cytotoxicity and anti‐plant pathogenic fungi activities. The quantum chemical calculations for the above‐mentioned compounds have been performed using B3LYP/6‐311++G (d,p) level of theory to get perceptive information about the molecules. After verifying the drug‐likeness of the title compounds, chemical reactivity has been analyzed through frontier molecular orbital analysis. The quantitative and qualitative description of activity at various sites has been investigated through conceptual DFT approach and molecular electrostatic potential surface analyses, respectively. In‐silico bioactivity studies of these compounds with the main protease (6LU7) present in SARS‐CoV‐2 causing COVID‐19, human breast cancer cell line (6VJ3), plant pathogenic fungi R. Solani (4G9N), and G. Zeae (2L2F) have exposed a reasonable binding affinity and inhibition constant with all these targets. [ABSTRACT FROM AUTHOR]

The Aharonov–Bohm effect is a genuine quantum effect typically characterized by a measurable phase shift in the wave function for a charged particle that encircles an electromagnetic field located in a region inaccessible to the particle. However, this definition is not possible in the majority of the phase-space descriptions since they are based on quasiprobability distributions. In this work, we characterize for the first time the Aharonov–Bohm effect within two different formalisms of quantum mechanics. One of them is the phase-space formalism relying on the canonical commutation relations and Weyl transform. In this framework, the aim is to obtain a consistent description of the quantum system by means of the quasiprobability Wigner function. The other one is the Segal–Bargmann formalism, which we mathematically describe and connect with quantum mechanics by means of the commutation relations of the creation and annihilation operators. After an introduction of both formalisms, we study the Aharonov–Bohm effect within them for two specific cases: one determined by a non-zero electric potential, and another determined by a non-zero magnetic vector potential. Subsequently, we obtain a more general description of the Aharonov–Bohm effect that encompasses the two previous cases and that we prove to be equivalent to the well-known description of this effect in the usual quantum mechanics formalism in configuration space. Finally, we delve into the Aharonov–Bohm effect, employing a density operator to depict states with positional and momentum uncertainty, showcasing its manifestation through distinctive interference patterns in the temporal evolution of Wigner functions under an electric potential, and emphasizing the intrinsically quantum nature of this phenomenon. [ABSTRACT FROM AUTHOR]

The reaction of the synthesized (E)‐1‐(4‐((2,4‐dihydroxy‐6‐methylphenyl)diazenyl)phenyl)ethan‐1‐one, (DMPDE) ligand with Ag(I) ion at room temperature resulted in the formation of the complex; [Ag(DMPDE)(H2O)2]. 1H NMR, 13C NMR, FTIR, UV‐Vis, mass spectra, elemental analyses, thermal analysis (TGA/DTA), and molar conductance measurements were done to elucidate the structure of synthetic compounds. The results revealed an interesting geometrical variation; tetrahedral for Ag(I) complex. FT‐IR spectra demonstrated that the ligand (DMPDE) under investigation behaves as a bidentate ligand (N,O) through the nitrogen atom of the azo group which is the farthest of the acetophenone moiety and oxygen phenolic for benzene moiety and forms a stable five‐membered chelating ring. The electronic structure, molecular electrostatic potential (MEP) and quantum chemical calculations of the newly synthesized compounds are investigated theoretically at the DFT/B3LYP level of theory. Additionally, the ligand (DMPDE) and Ag(I) complex were screened against the growth of pathogenic bacteria [Actinomycosis (G+), E. Escherichia Coli (G−)] and fungi (Penicillium spp.) compared with the reference antibiotics, Chloramphenicol and Nystatin. Furthermore, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) was used to evaluate the antioxidant activities of the ligand and its complex, which showed they both possess significant antioxidant properties in comparison with L‐ascorbic acid (Vit. C) as standard. Based on docking studies, (DMPDE) and Ag(I) complex demonstrated a greater affinity for (PDB ID: 3T88), which corresponds to Escherichia coli protein (−6.7818 kcal/mol) and (−6.7928 kcal/mol), respectively. Interestingly, the most active Ag(I) complex inside the active site of cervical cancer receptor (PDB ID: 4XR8) demonstrated a higher binding energy (−6.2631 kcal/mol) than free ligand (−5.8561 kcal/mol). In silico, ADMET displayed that compounds obey the Lipinski rule and the "Veber's rule. Consequently, is likely to exhibit oral bioavailability with good LD50 and a safety profile that includes non‐cytotoxicity, non‐immunotoxicity, and non‐skin sensitization. Finally, the compounds synthesized showed significant anticancer activity in human cervical cancer cell lines HeLa and SiHa compared with positive controls (cisplatin) and normal human hepatic cells (WRL‐68). In the present study, all tested cancer cell lines showed promising activity against Ag(I) complex, whose IC50 value ranged from (61.02 to 71.09) μg/mL. [ABSTRACT FROM AUTHOR]

In this report we have studied, the substitutional effect on photophysical properties of newly synthesized isomeric benzocoumarin‐Sesamol conjugates using absorption, steady‐state fluorescence emission, and time‐resolved emission measurements. The structural characterization of the synthesized dyes was carried out using FT‐IR, 1H‐NMR, 13C‐NMR, and MS. The ground state dipole moment of both the molecules in the gaseous phase is estimated from ab initio computations by using Gaussian 09W software and also from solvatochromic method and the results are compared. Stoke's shift exhibits a redshift with an increase in solvent polarity for synthesized indicating a π–π* transition. The HOMO‐LUMO energy gaps computed from density functional theory and absorption threshold wavelengths are found to be in good agreement with each other. The Global chemical reactivity descriptor parameter and electrostatic potential (MESP) plots suggest that molecules have strong electrophilic and nucleophilic sites. The preliminary photophysical observations and results suggest that the fluorescent dyes can be considered as potential material for the construction of solar cells, fluorescent probes, and chemosensors. [ABSTRACT FROM AUTHOR]

This paper presents an innovative approach to wireless cellular stimulation therapy through the design of a magnetoelectric (ME) microdevice. Traditional electrophysiological stimulation techniques for neural and deep brain stimulation face limitations due to their reliance on electronics, electrode arrays, or the complexity of magnetic induction. In contrast, the proposed ME microdevice offers a self-contained, controllable, battery-free, and electronics-free alternative, holding promise for targeted precise stimulation of biological cells and tissues. The designed microdevice integrates core shell ME materials with remote coils which applies magnetic temporal interference (MTI) signals, leading to the generation of a bipolar local electric stimulation current operating at low frequencies which is suitable for precise stimulation. The nonlinear property of the magnetostrictive core enables the demodulation of remotely applied high-frequency electromagnetic fields, resulting in a localized, tunable, and manipulatable electric potential on the piezoelectric shell surface. This potential, triggers electrical spikes in neural cells, facilitating stimulation. Rigorous computational simulations support this concept, highlighting a significantly high ME coupling factor generation of 550 V/m·Oe. The high ME coupling is primarily attributed to the operation of the device in its mechanical resonance modes. This achievement is the result of a carefully designed core shell structure operating at the MTI resonance frequencies, coupled with an optimal magnetic bias, and predetermined piezo shell thickness. These findings underscore the potential of the engineered ME core shell as a candidate for wireless and minimally invasive cellular stimulation therapy, characterized by high resolution and precision. These results open new avenues for injectable material structures capable of delivering effective cellular stimulation therapy, carrying implications across neuroscience medical devices, and regenerative medicine. [ABSTRACT FROM AUTHOR]

The gradual channel approximation forms the foundation for the analysis of field‐effect transistors. It has been used to discuss transistors that are not necessarily based on the field‐effect as well, such as the organic electrochemical transistor (OECT). Here, the applicability of the gradual channel approximation for OECTs is studied by a 2D drift‐diffusion model. It is found that OECT switching can be described by two separate effects—a doping/dedoping mechanism and the formation of an electrostatic double layer at the interface between the mixed conductor and the electrolyte. The balance between these two mechanisms is determined by the morphology of the mixed conductor, in particular the question if ions move in the same phase and electric potential as the holes, or if separate ion and hole phases are formed. It is argued that the gradual channel approximation can only be used to describe electrostatic switching at the mixed conductor/electrolyte interface (the two‐phase model), but cannot be employed to analyze devices operating on a doping/de‐doping mechanism (the one‐phase model). [ABSTRACT FROM AUTHOR]

CaTi 2 O 4 (OH) 2 :Eu3+, CaTiO 3 :Eu3+ and [CaTi 2 O 4 (OH) 2 –CaTiO 3 ]:Eu3+ were synthesized by a solvothermal method without the help of templates or surfactants. And their structures, luminescence properties, and photocatalytic properties were systematically studied. The RIR (reference intensity ratio) data of CaTi 2 O 4 (OH) 2 were first investigated via X-ray diffraction (XRD), thus the ratios of each phase in the (m%CaTi 2 O 4 (OH) 2 -n%CaTiO 3):3%Eu3+ biphasic mixture was determined. The bandgap value of CaTi 2 O 4 (OH) 2 :3%Eu3+ is 0.28 eV less than that of CaTiO 3 :3%Eu3+. The specific surface area of CaTi 2 O 4 (OH) 2 is 8.2 times larger than that of CaTiO 3. Compared with CaTiO 3 :Eu3+, the CaTi 2 O 4 (OH) 2 :Eu3+ showed stronger luminescence intensity. The Judd-Ofelt theory analysis show that the Eu3+ ions in CaTi 2 O 4 (OH) 2 :Eu3+ have low local symmetry, high Eu–O bonds covalence and low ligands electron density. The photocatalytic properties of CaTi 2 O 4 (OH) 2 :y%Eu3+, CaTiO 3 :x%Eu3+ and [62.2%CaTi 2 O 4 (OH) 2 -37.8%CaTiO 3 ]:3% Eu3+ were comparatively studied in detail. The band-gap value of [62.2 % CaTi 2 O 4 (OH) 2 –37.8%CaTiO 3 ]:3%Eu3+ is significantly reduced due to the presence of heterojunctions compared to CaTi 2 O 4 (OH) 2 :y%Eu3+ and CaTiO 3 : x%Eu3+. The built-in electric potential at heterojunction interface will guide electrons and holes to move in opposite directions, therefore [CaTi 2 O 4 (OH) 2 –CaTiO 3 ]:Eu3+ has excellent photocatalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

The HClO scavenging capacity of a group of heteroaryl‐nitrones (HA−N) that contain a substituted five‐membered ring (furan or thiophene) in their structure was studied using experimental and quantum computational methods. Experimentally, it was found that four HA−N showed scavenging activity with IC50 values ranging from 26.15 to 61.20 nM, while two HA−N were found to be inactive. To explain the HClO activity of the analyzed HA−N, we proposed and investigated a reaction mechanism based on a nucleophilic attack by the hypochlorous anion (pKa=7.46) on α‐carbon of each HA−N, taking into account the results obtained by calculating the electrostatic potential. For this purpose, we used the B3LYP functional of the density functional theory (DFT) and the basis set 6‐311+G(d,p) included in the Gaussian 09 program. We calculated the rate constants (k), the HOMO and LUMO energies, and several reactivity indices such as the electronic chemical potential (μ), chemical hardness (η), and global electrophilicity (ω) to establish a quantified relationship with the observed activities. The SAR analysis and the correlation between the rate constants and the global electrophilicity with the HClO scavenging activity allow us to explain the experimental activity presented by the six HA−N analyzed here. [ABSTRACT FROM AUTHOR]

With the widespread application of the direct-current resistivity method, searching for accurate and fast-forward algorithms has become the focus of research for geophysicists and engineers. Three-dimensional forward modeling can be the best way to identify geo-electrical anomalies but are hampered by computational limitations because of the large amount of data. A practical compromise, or even alternative, is represented by 2.5D modeling characterized using a 3D source in a 2D medium. Thus, we develop a 2.5D direct-current resistivity forward modeling algorithm. The algorithm incorporates the finite-difference approximation and fictitious point technique that can improve the efficiency and accuracy of numerical simulation. Firstly, from the boundary value problem of the electric potential generated by the point source, the discrete expressions of the governing equation are derived from the finite-difference approach. The numerical solutions of the discrete electric potential are calculated after the approximate treatment of the boundary conditions with a finite-difference method based on a fictitious point scheme. Secondly, through the simulation of a homogeneous half-space model and a one-dimensional model, and compared with the analytical results, the correctness and stability of the finite-difference forward algorithm are verified. Lastly, through the numerical simulation for a two-dimensional model, 2.5D direct-current sounding responses are summarized, which can provide a qualitative interpretation of field data. [ABSTRACT FROM AUTHOR]

The innovative synthesis of 3,8-dibromo-2,9-dinitro-5,6-dihydrodiimidazo [1,2-a:2′,1′-c]pyrazine and 3,9-dibromo-2,10-dinitro-6,7-dihydro-5H-diimidazo [1,2-a:2′,1′-c][1,4]diazepine is described in this study. The tricyclic fused molecular structures are formed by the respective amalgamation of piperazine and homopiperazine with the imidazole ring containing nitro. Compound 1 and 2 possess excellent high-density physical properties (ρ1 = 2.49 g/cm3, ρ2 = 2.35 g/cm3) due to the presence of a fused ring structure and Br atom. In addition to their high density, they have high decomposition temperatures (Td > 290 °C) which means that they have excellent thermal stability and can be used as potential heat-resistant explosives. Low mechanical sensitivities (IS > 40 J, FS > 360 N) are observed. The twinning structure of 2 was resolved by X-ray diffraction. Non-covalent interaction analysis, Hirshfeld surfaces, 2D fingerprint plot, and Electrostatic potential analysis were used to understand the intramolecular interactions in relation to physicochemical properties. The unique structures of this type of compound provide new potential for the evolution of energetic materials. [ABSTRACT FROM AUTHOR]

A new Schiff base ligand of 6,6′-(1Z,1′Z)-(butane-1,4-diylbis(azanylyidene))bis (phenylmethanylylidene))bis(3-octyloxy) phenol) was synthesized and characterized using XRD and different spectroscopic analyses (FTIR, 1H NMR, 13C NMR, and UV–Vis.) DFT/B3LYP/6-31G(d,p) level of theory was applied successfully to the present compound. Theoretically calculated parameters of the synthesized compound were compared with the experimentally obtained results. The optimized structure has been investigated using the same level of theory for various studies, including frontier molecular orbital analysis, molecular electrostatic potential, chemical reactivity indexes, natural bond orbital analysis, electrostatic potential, and the electrophilicity-based charge transfer with DNA bases. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) material with Janus-induced built-in electric field, has become a research focus arising from their characteristic physical and chemical properties, especially in photocatalytic water splitting applications. Herein, we introduce a novel family of 2D Janus materials, named ScXAlY (X/Y = P, As), and prove these Janus materials and their heterostructures as promising water splitting photocatalytic candidate materials, leveraging first-principles calculations. All Janus structures and heterostructures exhibit strong dynamical, thermal, and mechanical stabilities. These 2D Janus ScXAlY materials possess wide band gaps, excellent electronic carrier mobilities, and appropriate band edges to facilitate overall water splitting, and moreover can attain Janus-induced built-in electric field effect. Interestingly, the heterostructures (ScXAlY/ScXAlY) surpass the individual materials in performance, demonstrating enhanced solar-to-hydrogen (STH) efficiencies (>30 %) and increscent electrostatic potential differences (>0.85 eV). Furthermore, they show comprehensive photoabsorption across the visible light spectrum, with peak absorptions more than doubling those of the single materials. These heterostructures also display effective spatial separation of electrons and holes which can further boosting their photocatalytic capabilities. Our findings underscore the potential of Janus ScXAlY materials and their heterostructures, in facilitating visible-light-driven photocatalytic water splitting, showcasing a promising avenue for advancement in this burgeoning field. • 2D Janus ScXAlY (X/Y = P, As) are promising water splitting photocatalysts. • Heterostructures (ScXAlY/ScXAlY) own super-high STH efficiencies (>30 %). • Photoabsorptions of heterostructures cover the whole visible-light region. [ABSTRACT FROM AUTHOR]

In the paper, electrochemical behavior of platinum based cathode catalyst in a polymer electrolyte membrane fuel cell is studied under non-symmetric square-wave electric potential cycling applied in accelerated stress test. Following the modeling by Holby and Morgan, degradation due to Pt dissolution, ion diffusion, and oxide coverage is performed with respect to cycling operating conditions and model parameters. The computer simulation demonstrates impact of the electrochemical surface area loss rate under variation of the temperature, pH, platinum particle diameter, loading, Pt to Carbon volume fraction, and their simultaneous effect. From physical consistency and multi-parametric sensitivity analysis, a statement on feasible domain of the parameters for the PEMFC operation is concluded. • Holby–Morgan model of platinum electrochemical degradation in PEMFC is applied. • The catalyst degradation is calculated under EU FCH 2JU AST cycling protocol. • ECSA ratio loss rate is correlated with operating conditions and model parameters. • Sensitivity analysis gives feasible range of multiple variable parameters. • Temperature, pH, Pt particle diameter, loading, and Pt/C volume fraction are tested. [ABSTRACT FROM AUTHOR]

Collective interactions are a novel type of bond between metals and AX3 fragments with an electropositive central atom, A, and electronegative X substituents. Here, using electrostatic potential maps and state-of-the-art bonding analysis tools we have shown that collective interactions are anti-electrostatic cation⋯π-Hole or cation⋯lp-Hole interactions. [ABSTRACT FROM AUTHOR]

This work aims to find how coupled energy per pulse influences the ability of a pulsed dielectric barrier discharge (DBD) plasma to ignite fuel-lean methane–air flow. For that, experiments are performed on a custom-built DBD flow reactor with a variable dielectric thickness and the discharge is operated by bursts of 10 ns duration pulses at 3 kHz repetition rate. With an increase in dielectric thickness, we observe that the coupled energy per pulse decreases even though applied voltage conditions are similar and so more pulses are required to ignite the lean mixture. Interestingly, we observe a significant increase in the minimum ignition energy (MIE) with an increase in the thickness beyond 3 mm. Moreover, the ignition kernel growth rate is much slower in the thicker dielectric cases even though total energy coupling per burst is similar. This phenomenon is investigated further by evaluating plasma parameters using electrical and optical diagnostics. Effective dielectric capacitance, discharge current, and voltage drop across the gas gap are derived from an equivalent circuit analysis, whereas plasma gas temperature and effective reduced electric field ( E / N) are estimated from optical emission spectroscopy. From these analyses, we conclude that a thicker dielectric limits the discharge current and so the plasma filament temperature. For more than 3 mm thick dielectric cases, the filament heating per pulse is too low to achieve strong enough plasma pulse-to-pulse coupling which eventually leads to higher MIE and slower ignition kernel growth rate or the inability to ignite at all. [ABSTRACT FROM AUTHOR]

The primary issue for the commercialization of proton exchange membrane fuel cells (PEMFCs) is the carbon corrosion of support and dissolution agglomeration of platinum nanoparticles under start-up/shut-down (SU/SD) conditions. Carbon nanotubes (CNTs)-supported Pt nanowire (PtNW) catalyst toward the ORR was synthesized via the soft template method. Electrochemical characterization demonstrated that the PtNW/CNTs showed higher activity than Pt/C because the anisotropy of the 1D structure strengthened its ability to transport electrons. An accelerated stressed test between 1.0 and 1.5 V for carbon corrosion was performed to examine durability at a single cell under practical SU/SD conditions. After 5000 cycles, the voltage drop was 0.142 V, and the voltage decay rate was 0.0284 mV cycle−1 for the PtNW/CNTs catalyst at 1600 mA cm−2; the voltage drop was 0.417 V, and the voltage decay rate was 0.0834 mV cycle−1 for the Pt/C catalyst at 1600 mA cm−2. The Pt/C catalyst demonstrated severe Pt nanoparticle aggregation and growth with a wide size distribution, whereas the PtNW/CNTs catalyst showed a slight variation. The PtNW/CNTs catalyst showed remarkable durability after 5000 SU/SD cycles. Consequently, PtNW/CNTs is a promising electrocatalyst, which can replace traditional Pt/C catalyst in PEMFCs. • PtNW/CNTs were synthesized using the soft template method with CNTs as support. • The start-up/shut-down event was analyzed and simulated with a measurable protocol. • The ORR activity and the electrochemical stability of the PtNW/CNTs catalyst were remarkably improved. • The PtNW/CNTs catalyst has better performance and life of single cell than the Pt/C catalyst. [ABSTRACT FROM AUTHOR]

Reducing p‐nitrophenol (PNP) to p‐aminophenol is an industrially relevant synthesis. Nevertheless, only a few heterogeneous catalysts have been evaluated for the reduction of PNP by glycerol. Appropriate quantum computational studies can screen potential catalysts for this crucial green reaction. The present research investigates the catalytic activities of Pd@Ag and Ni@Ag core‐shell nanogeometries toward PNP reduction by glycerol through density functional theory (DFT) calculations. The central atom of a geometry‐optimized 13‐atom Ag cluster was replaced by Pd and Ni atoms to create the core‐shell morphologies. The interaction energies of PNP and glycerol with each of the (metal/bimetallic) clusters were evaluated by DFT calculations to find the best PNP and glycerol molecule orientation with the respective bimetallic cluster. Electrostatic potential surface and natural bond orbital analyses were performed to study the charge distribution and transfer between atomic orbitals. The frequencies of vibrational modes in isolated PNP/glycerol structures were compared to those when these molecules were in the presence of the different metal clusters to infer the effect of the interactions. All performed analyses indicated improved catalytic activity toward PNP reduction by glycerol upon Ni‐doping of the Ag13 cluster. [ABSTRACT FROM AUTHOR]

The integration of water electrolysis with renewable energy sources (RESs) constitutes a milestone in the transition to neutral and sustainable energy systems. The attractive features of the Proton Exchange Membrane (PEM) electrolyzer such as high purity of hydrogen, operation with high pressure, and high current densities have made it a critical technology to produce green hydrogen from RESs. Accurate models are required for proper design, analysis, and control of the electrolyzer when connected to the grid or renewable energy systems. Amongst the various types of models proposed for modeling the PEM electrolyzer, electrical circuit models are the easiest, most appealing, and straightforward to use for the investigation of electrolyzer operation and control. This paper presents an exhaustive review of the electrical circuit modeling reported in the literature on PEM electrolyzers. The reviewed models are classified analogously to the classifications of physical modeling in terms of voltage components (reversible, ohmic, activation, and concentration voltage drop), model behavior (static/dynamic), and modeling scale (cell/stack). Furthermore, MATLAB simulations of the reviewed models are implemented and the results are compared to pinpoint their similarities and deviations. Moreover, the applications, challenges, benefits, and drawbacks of the electrolyzer's electrical equivalent circuit modeling are discussed and overarching recommendations are set out for further research on the PEM electrolyzer modeling. The paper can be used as a comprehensive reference for choosing the appropriate electrical model of the electrolyzer for beginners as well as for research and industry experts who rely on PEM electrolyzer models in their work. • A comprehensive review of the electrical circuit models of the PEM electrolyzer is presented. • The models are classified in terms of voltage components, model behavior, and scale. • Simulations of the models are implemented to show their similarities and deviations. • Applications, benefits, and drawbacks of electrical circuit modeling are discussed. • Overarching technical recommendations are drawn for further research on electrical circuit modeling. [ABSTRACT FROM AUTHOR]