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Magnetically induced heterogeneous catalysis has been attracting attention due to its high energy efficiency and flexibility for dynamic reactor control. Iron wool is a commercial, low-cost, and versatile heating agent, which has been used in several magnetic catalysis studies, but its heating properties have never been investigated. Here, the properties of three types of Fe wool were studied using optical and electronic microscopy, x-ray diffraction, and measurements of both heating power and high-frequency hysteresis loops. The effects of strand width, packing, and magnetic field amplitude and frequency were studied. A maximum specific absorption rate (SAR) around 700 W/g under a rms field of 47.4 mT at 93 kHz was measured for the larger width Fe wool. High-frequency hysteresis loops were used to quantify the contribution of hysteresis losses and eddy currents to total heating. Eddy currents contribute 65%–90% to the global heating depending on the strand width. Coating the wool with SiO2 and Ni has negative effects on the SAR but none on hysteresis losses. It is interpreted as originating from the cut-off of inter-wire eddy currents due to the insulating (SiO2, oxidized Ni) nature of the coating. Last, it was found that adding more Fe wool in a given volume mostly decreases the SAR. This effect could be not only due to the absorption and/or screening of the field by surface strands but also due to magnetic interactions. The results described in this work give insights into the magnetic heating of microscale magnetic materials and optimize their use for heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Epitaxial films of BiAl x Fe 1 − x O 3 (xBAFO) were grown on SrTiO 3 (STO) and SrRuO 3 buffered STO substrates using pulsed laser deposition. To understand the effects of Al substitution at the Fe-site of BFO, we systematically investigated its impact on the material's crystal structure, surface morphology, ferroelectric properties, and magnetic properties. Our x-ray diffraction analysis revealed that phase-pure xBAFO films can be stabilized for Al concentrations between 0% and 35%, without the formation of secondary phases, due to the isotypic crystal structures of BiAlO 3 and BiFeO 3. This allowed the rhombohedral structure of BAFO to be preserved. We then characterized the ferroelectric properties of xBAFO (0 ≤ x ≤ 0.25) by analyzing polarization-voltage hysteresis loops, which exhibited a transition from a nearly square shape to a more slanted shape with increasing Al substitution. Additionally, piezoresponse force microscopy revealed that the domain growth mode, shape, size, dimension, and nucleation play a crucial role in the switching behavior of ferroelectric materials. Furthermore, we observed a modest enhancement in magnetization due to the modified spin ordering of Fe atoms with Al substitution. Notably, the optimal ferroelectric and magnetic properties were achieved at an Al concentration of 15%. These findings suggest that BAFO is a promising magnetoelectric material with desired functionalities for realizing BFO-based next-generation non-volatile memory devices. [ABSTRACT FROM AUTHOR]

Recent studies have shown that proximity effects are able to substantially modulate the superconducting properties of various quasi-two-dimensional layered materials such as FeSe, FeSeTe, NbSe2, and NbS2. Due to their high surface charge concentration and high dielectric constants, ferroelectric materials provide an interesting avenue for inducing proximity effects in layered superconductors. In this study, we explore the interactions between FeSeTe and the two-dimensional ferroelectrics CuInP2S6 and CuInP2Se6. We found that contrary to the normal behavior of FeSeTe, FeSeTe/CuInP2S6, and FeSeTe/CuInP2Se6 heterostructures display a peculiar two-step superconducting transition. Further testing revealed a hysteresis loop in the IV curves of these samples when measured below the critical temperature indicating the presence of disorder and domains within FeSeTe. We conclude that these domains are responsible for the two-step transition in FeSeTe and hypothesize that they are induced by the domain structure of the aforementioned ferroelectric materials. [ABSTRACT FROM AUTHOR]

Switching Spectroscopy Piezoresponse Force Microscopy (SSPFM) stands out as a powerful method for probing ferroelectric properties within materials subjected to incremental polarization induced by an external electric field. However, the dense data processing linked to this technique is a critical factor influencing the quality of obtained results. Furthermore, meticulous exploration of various artifacts, such as electrostatics, which may considerably influence the signal, is a key factor in obtaining quantitative results. In this paper, we present a global methodology for SSPFM data processing, accessible in open-source with a user-friendly Python application called PySSPFM. A ferroelectric thin film sample of potassium sodium niobate has been probed to illustrate the different aspects of our methodology. Our approach enables the reconstruction of hysteresis nano-loops by determining the PR as a function of applied electric field. These hysteresis loops are then fitted to extract characteristic parameters that serve as measures of the ferroelectric properties of the sample. Various artifact decorrelation methods are employed to enhance measurement accuracy, and additional material properties can be assessed. Performing this procedure on a grid of points across the surface of the sample enables the creation of spatial maps. Furthermore, different techniques have been proposed to facilitate post-treatment analysis, incorporating algorithms for machine learning (K-means), phase separation, and mapping cross correlation, among others. Additionally, PySSPFM enables a more in-depth investigation of the material by studying the nanomechanical properties during poling, through the measurement of the resonance properties of the cantilever–tip–sample surface system. [ABSTRACT FROM AUTHOR]

The time-dependent quantum transportation through a metal/polymer/metal system is theoretically investigated on the basis of a Su–Schrieffer–Heeger model combined with the hierarchical equations of motion formalism. Using a non-adiabatic dynamical method, the evolution of the electron subspace and lattice atoms with time can be obtained. It is found that the calculated transient currents vary with time and reach stable values after a response time under the bias voltages. However, the stable current as the system reaches its dynamical steady state exhibits a discrepancy between two sweep directions of the bias voltage, which results in pronounced electrical hysteresis loops in the current–voltage curve. By analyzing the evolution of instantaneous energy eigenstates, the occupation number of the instantaneous eigenstates, and the lattice of the polymer, we show that the formation of excitons and the delay of their annihilation are responsible for the hysteretic current–voltage characteristics, where electron–phonon interactions play the key factor. Furthermore, the hysteresis width and amplitude can also be modulated by the strength of the electron–phonon coupling, level-width broadening function, and temperature. We hope these results about past condition-dependent switching performance at a sweep voltage can provide further insight into some of the basic issues of interest in hysteresis processes in conducting polymers. [ABSTRACT FROM AUTHOR]

The solid-state refrigeration technique based on the electrocaloric effect (ECE) of ferroelectric materials has been regarded as a promising alternative to vapor compression systems due to its advantages of high efficiency and easy miniaturization. However, the small adiabatic temperature change (ATC) and narrow operating temperature range of ferroelectric materials are key obstacles for their practical applications of ECE refrigeration. To improve the ECE performance of ferroelectric polymer poly(vinylidene fluoride) [P(VDF-TrFE)], PbZr1−xTixO3 (PZT) nanoparticles with larger polarization is herein introduced to form ferroelectric nanocomposites. The phase-field simulation is employed to investigate the dynamic hysteresis loops and corresponding domain evolution of the ferroelectric nanocomposites. The temperature-dependent ATC values are calculated using the indirect method based on the Maxwell relation. The appearance of the double hysteresis loop is observed in P(VDF-TrFE) nanocomposite filled with PbZr0.1Ti0.9O3 nanoparticles [P(VDF-TrFE)–PZT0.9], which is mainly caused by a microscopic domain transition from single domain to polar vortex. Compared to the P(VDF-TrFE), enhanced ATC values associated with the domain transition are unveiled in P(VDF-TrFE)–PZT0.9, and the temperature range of excellent ECE is also effectively broadened. In addition, as the component x of filled PZT nanoparticles increases to cross the morphotropic phase boundary (MPB), the maximum ATC value shows a significant increase. The results presented in this work not only explain the mechanism of domain transition induced excellent ECE in the P(VDF-TrFE)–PZT nanocomposite, but also stimulate future studies on enhancing ECE of P(VDF-TrFE) by introducing ferroelectric nanofillers. [ABSTRACT FROM AUTHOR]

This study investigates the out-of-plane magnetization component of electrodeposited Ni90Fe10 thin films grown under different applied magnetic field conditions. The formation of stripe domains is gradual, as there is a thickness range in which the transcritical shape appears in the hysteresis loops, while only magnetic ripples are measured in the magnetic force microscopy images. For instance, samples deposited under the residual magnetic field generated by the switched-off magnetic stirrer exhibit the transcritical shape in the in-plane hysteresis loops at a thickness of 400 nm, even though corresponding magnetic force microscopy images do not reveal the presence of stripe domains. When a perpendicular magnetic field of 100 Oe is applied during growth, stripe domains become visible in microscopy images, along with the transcritical shape in the hysteresis loop at 400 nm. This implies that the critical thickness for stripe formation can be reduced by applying a perpendicular magnetic field during electrodeposition. We have experimentally confirmed that the larger the magnetic field applied in the out-of-plane direction during growth, the smaller the critical thickness. These results underscore the importance of controlling the external magnetic field during electrodeposition for more effective tuning of the magnetic textures in electrodeposited Ni90Fe10 films. [ABSTRACT FROM AUTHOR]

Dynamic responses of copper titanates to alternating electric fields with different strengths are characterized in terms of dielectric spectrums. This work extends the introduction of quasipolaron surface polarization (QSP). A collective of quasipolarons pinned at grain surfaces is involved in the electric polarization, which is confirmed by the quadratic polarization–permittivity relation. Because electric polarization is a macroscopic quantum effect, the QSP is described in terms of the density of states (DOS). As a sign of reverse ferroelectricity, dielectric hysteresis loops of reverse-S shape reveal that the characteristic remnant polarization is proportional to the DOS ratio of quasipolaron surface excited to ground states. Although the DOS of the surface ground state is dependent on the mole ratio of quasipolaron quantity, both the DOS and the energy levels of surface excited states show the intrinsic angular-frequency dependence in a power function manner. [ABSTRACT FROM AUTHOR]

Ferroelectric transition and polarization characteristics were explored for filled tungsten bronze Ba4Sm2Ti4Nb6O30 ceramics with pinched P–E hysteresis loops. Two dielectric permittivity peaks were observed at around 553 and 486 K on heating and cooling cycles, respectively, with a large thermal hysteresis (∼77 K), indicating the first-order ferroelectric phase transition behavior in the present ceramics. In addition, a low-temperature dielectric relaxation appeared at around 300 K, following the Vogel–Fulcher relationship, which is related to thermal activation related to the polarization in the ab plane. Pinched P–E hysteresis loops were detected in the temperature range of 293–453 K with two pairs of coercive fields, indicating certain polar reversal mechanism, while E1 corresponds to the reversal field needed for all the ferroelectric domains in the system, and E2 is the back switch field from the polar state to the nonpolar state. Therefore, (E1–E2)/2 is the effect coercive field for the polar domain induced by the field transition. Temperature dependence of the coercive fields E1, E2, and (E1–E2)/2 is fitted to the Vopsaroiu model with different activated energies obtained for different temperature ranges, based on which the polarization dynamics of the pinched hysteresis loops are discussed. [ABSTRACT FROM AUTHOR]

The phenomenon of exchange bias has been extensively studied within crystalline materials, encompassing a broad spectrum from nanoparticles to thin-film systems. Nonetheless, exchange bias in amorphous alloys has remained a relatively unexplored domain, primarily owing to their inherently uniform disordered atomic structure and lacking grain boundaries. In this study, we present a unique instance of exchange bias observed in Fe–B–Nb amorphous thin films, offering insights into its origins intertwined with the system's spin-glass-like behavior at lower temperatures. The quantification of exchange bias was accomplished through a meticulous analysis of magnetic reversal behaviors in the liquid-helium temperature range, employing a zero-field cooling approach from various initial remanent magnetization states (±MR). At reduced temperatures, the appearance of asymmetric hysteresis, a hallmark of negative exchange bias, undergoes a transformation into symmetric hysteresis loops at elevated temperatures, underscoring the intimate connection between exchange-bias and dynamic magnetic states. Further investigations into the magnetic thermal evolution under varying probe fields reveal the system's transition into a spin-glass-like state at low temperatures. We attribute the origin of this unconventional exchange bias to the intricate exchange interactions within the spin-glass-like regions that manifest at the interfaces among highly disordered Fe-nuclei. The formation of Fe-nuclei agglomerates at the sub-nanometer scale is attributed to the alloy's limited glass-forming ability and the nature of the thin-film fabrication process. We propose that this distinctive form of exchange bias represents a novel characteristic of amorphous thin films. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW)-layered materials, such as graphite, exhibit unique mechanical properties owing to their structural and mechanical anisotropies. This study reports the development of a mechanical model that reproduces the characteristics of the nonlinear and reversible bending deformation of vdW-layered materials, while taking into account the microscopic mechanism of the discrete interlayer slips. The vdW-layered material was modeled as a stack of interacting discrete deformable layers (semi-discrete layer model), and the interlayer interaction was modeled using a cohesive zone model that reproduced the localized interlayer slip. Using the finite-element method, out-of-plane bending deformation analyses were performed on the cantilevers of the highly oriented pyrolytic graphite (HOPG) and MoTe2, and the validity of the model was verified by comparing it with the experimental results. The model accurately reproduced the loading and unloading behaviors in the experiments for the submicron HOPG cantilevers or the large nonlinear and reversible deformation with a hysteresis loop. Furthermore, the model reproduced well the characteristics of the bending experiments for the micro-MoTe2 cantilevers, or the intermittent decrease in stiffness during the loading process and deformation restoration during the unloading process. These results demonstrated that the designed semi-discrete layer model can be universally applied to reproduce the bending deformation characteristics of a variety of vdW-layered materials and can be employed to effectively elucidate the underlying deformation mechanisms. [ABSTRACT FROM AUTHOR]

We develop a semi-analytical model of self-diffusioosmotic transport in active pores, which includes advective transport and the inverse chemical reaction that consumes solute. In previous work [Antunes et al., Phys. Rev. Lett. 129, 188003 (2022)], we have demonstrated the existence of a spontaneous symmetry breaking in fore-aft symmetric pores that enables them to function as a micropump. We now show that this pumping transition is controlled by three timescales. Two timescales characterize advective and diffusive transport. The third timescale corresponds to how long a solute molecule resides in the pore before being consumed. Introducing asymmetry to the pore (either via the shape or the catalytic coating) reveals a second type of advection-enabled transition. In asymmetric pores, the flow rate exhibits discontinuous jumps and hysteresis loops upon tuning the parameters that control the asymmetry. This work demonstrates the interconnected roles of shape and catalytic patterning in the dynamics of active pores and shows how to design a pump for optimum performance. [ABSTRACT FROM AUTHOR]

Giant magnetostrictive material (GMM) is well known for its hysteresis behaviors related to multiple influencing factors, such as bias magnetic field and excitation level. This feature greatly challenges the loss prediction of giant magnetostrictive transducers. The existing loss prediction models need further improvement to cover the sensitive magnetic properties of GMM. In this paper, the variations of the iron losses with the operation conditions are interpreted by the variations of the Jiles–Atherton model parameters, and a concise parameter identification procedure with great generalizability is proposed. The iron losses of Terfenol-D under variable excitation levels and the DC biases are further investigated. With the proposed procedure, the introduced eight additional modification parameters for the original Jiles–Atherton model are easy to obtain, and merely a few hysteresis loops of Terfenol-D are involved. An experimental setup is established for further demonstration. Comparisons between the measured and calculated results indicate the effectiveness of the proposed approach. Throughout the bias-excitation space within the frequency range under investigation, the iron losses can be precisely estimated with an acceptable error of less than 5%. [ABSTRACT FROM AUTHOR]

Novel asymmetrical Fe(III) Schiff base coordination complexes, with the N4O2 coordination environment, exhibiting abrupt spin crossover (SCO) behaviour with a wide hysteresis loop of 27 K, have been synthesised from an ethylenediamine based asymmetrical Schiff base ligand viz. N-(2-aminoethyl)salicylaldimine (saen) and characterised via single crystal XRD measurements, variable temperature magnetic studies and Mössbauer measurements. The single crystal XRD measurements prove that the compound is a mixture of two fractions, one with methanol and the other without methanol, viz, [Fe(saen)2]NO3·CH3OH at 299 K (1–299) and at 173 K (1–173) and [Fe(saen)2]NO3 at 173 K (2–173), confirming that the Fe(III) centre has a distorted octahedral coordination geometry having two deprotonated asymmetrical tridentate saen ligands, counterbalanced by a nitrate anion and methanol solvent molecule in 1 while 2 has a non-solvate form. An extended hydrogen bonding network between the amino hydrogen atoms of the saen ligand, nitrate counteranion, and methanol solvate molecule is observed in fraction 1, while an extended zig-zag hydrogen bonding between the nitrate anion and amino hydrogens of saen is observed in fraction 2. Furthermore, the complex has been characterised by variable temperature magnetic susceptibility measurements and 57Fe Mössbauer spectroscopy, confirming the SCO nature. [ABSTRACT FROM AUTHOR]

A novel hyperbolic system of partial differential equations is introduced to model traffic flows. This system comprises three equations, with two being linearly degenerate; its main feature is the inclusion of a hysteretic term in a generalized Aw–Rascle–Zhang (ARZ) model. First, a maximum principle for the diffusive version of the model is proven. Then, it is demonstrated that a solution to the Riemann problem exists, which is unique among solutions that are monotone in velocity; all waves exploited in the construction have suitable viscous profiles. Through several examples it is shown how, as a consequence of different driving habits, the system can model the decay, emergence, or persistence of stop‐and‐go waves (a feature that is missing in the ARZ model), and such behavior is characterized by a simple geometric condition. Furthermore, the model allows the study of traffic flows with a mixture of drivers whose hysteresis loops are either clockwise or counterclockwise. In particular, the presence of sufficiently many of the former dampens speed oscillations. [ABSTRACT FROM AUTHOR]

The increasing frequency of extreme weather events, such as hurricanes and rising sea levels due to climate change, presents significant challenges to coastal infrastructure. With 42% of bridges in the United States exceeding 50 years of age, which surpasses their intended service life, there is a pressing need to assess their structural integrity, especially in coastal regions. This study focuses on evaluating the structural performance of bearing pads in coastal bridges under hurricane-induced wave loadings. Utilizing a combination of physics-based models (PBM), nonlinear modal time history analysis, and numerical validation, the research examines the hysteresis response of eight distinct bearing pad configurations. The findings indicate that reinforced circular bearing pads exhibit significantly greater shear displacements compared to plain elastomeric pads, underscoring the critical influence of shape factors on shear response. Fragility functions developed in the study illustrate the probability of shear failure, with reinforced circular pads showing a 28% higher likelihood of exceedance compared to rectangular plain pads. These results highlight the necessity for advanced design methodologies specifically for bearing pads to enhance the resilience of coastal infrastructure against severe hydrodynamic forces induced by hurricanes. [ABSTRACT FROM AUTHOR]

The pursuit of high-efficiency and zero-emission refrigeration technologies has spurred interest in electrocaloric (EC) refrigeration utilizing ferroelectric (FE) materials, where accurate characterization of the EC effect is crucial for comprehending its underlying physical mechanisms and for developing high-performance EC materials. In this study, we investigate the influence of unsaturated vs saturated FE polarization characteristics on EC effects using Pb0.99Nb0.02[(Zr0.6Sn0.4)0.85Ti0.15]0.98O3 ceramics. Direct EC measurement reveals that unsaturated loops can introduce substantial errors and even fake negative EC effects when employing the Maxwell approach for indirect EC measurement. In contrast, relatively accurate indirect EC results can be obtained using saturated FE hysteresis loops. Furthermore, it also highlights the necessity for saturated polarization conditions to achieve optimal EC performance in FEs. This work not only emphasizes the importance of carefully selecting polarization data for indirect EC measurements, but also presents a universal strategy to enhance EC effects in various materials. [ABSTRACT FROM AUTHOR]

Dielectric capacitors based on polycrystalline ferroelectrics have attracted much attention due to their significant power density and fast charge–discharge speed. The energy storage performance of polycrystalline ferroelectrics is highly dependent on the grain size and grain boundary. Here, the effect of grain size and grain boundary on the domain structures and polarization–electric field (P–E) hysteresis loops of polycrystalline ferroelectrics are investigated by using a phase-field model based on the time dependent Ginzburg–Landau (TDGL) equation. It is found that the depolarization field in the grain boundary induces the vortex domain when the grain size is reduced or the grain boundary thickness increases in certain extent, resulting in slender P–E loops, which contributes to an improvement in the energy storage efficiency and density. However, as the grain size further decreases or the grain boundary thickness further increases, the energy storage density decreases, which is attributed to the concurrent reduction in both the remnant and saturation polarizations. This study provides a considerable insight for optimizing the energy storage performance by carefully adjusting the grain size and grain boundary thickness in polycrystalline ferroelectrics. [ABSTRACT FROM AUTHOR]

In this study, we report the biosynthesis of Nickel ferrite using Ocimum sanctum leaf extract (OSLE@NiFe2O4). The single-phase cubic spinel structure of the synthesized nickel ferrite was confirmed by powder X-ray diffraction (PXRD) analysis. Structural characteristics were further examined using FTIR analysis. Optical and morphological properties were investigated through UV–DRS and FESEM studies. The magnetic hysteresis loop (M-H loop) confirmed the superparamagnetic nature of OSLE@NiFe2O4 nanoparticles. The photocatalytic degradation of Congo Red (CR) dye by the synthesized OSLE@NiFe2O4 nanoparticles was explored, revealing a pseudo-first-order kinetic behavior with a degradation efficiency of 99.9% and a rate constant of 0.06min−1. These findings demonstrate the superior photocatalytic activity of the biosynthesized nickel ferrite nanoparticles, highlighting their significant potential for efficient dye removal. [ABSTRACT FROM AUTHOR]

Multiferroic materials have been intensively pursued to achieve the mutual control of electric and magnetic properties. The breakthrough progress in 2D magnets and ferroelectrics encourages the exploration of low-dimensional multiferroics, which holds the promise of understanding inscrutable magnetoelectric coupling and inventing advanced spintronic devices. However, confirming ferroelectricity with optical techniques is challenging in 2D materials, particularly in conjunction with antiferromagnetic orders in single- and few-layer multiferroics. Here, we report the discovery of 2D vdW multiferroic with out-of-plane ferroelectric polarization in trilayer NiI2 device, as revealed by scanning reflective magnetic circular dichroism microscopy and ferroelectric hysteresis loops. The evolution between ferroelectric and antiferroelectric phases has been unambiguously observed. Moreover, the magnetoelectric interaction is directly probed by magnetic control of the multiferroic domain switching. This work opens up opportunities for exploring multiferroic orders and multiferroic physics at the limit of single or few atomic layers, and for creating advanced magnetoelectronic devices. The authors find the coexistence of ferroelectric and antiferroelectric states induced by chiral degeneracy in helical magnetic order in trilayer NiI2, along with the emergence of exotic magnetoelectric coupling. [ABSTRACT FROM AUTHOR]

Context: We explore the influence of strongly hydrophilic confinement on various properties of water, such as density, enthalpy, potential energy, radial distribution function, entropy, specific heat capacity, structural dynamics, and transition temperatures (freezing and melting temperatures), using monatomic water (mW) model. The properties of water are found to be dependent on confinement and the wall-fluid surface interaction. Hysteresis loops are observed for density, enthalpy, potential energy, and entropy around the transition temperatures, while the size of hysteresis loops varies with confinement and surface interaction. In smaller pore sizes (H ≤ 20), the solid phase displays a higher density compared to the liquid phase, which is unconventional behavior compared to bulk water systems due to the pronounced hydrophilic properties of the confinement surface. Specific heat capacity exhibits more oscillations in the confined system compared to bulk water, stemming from uneven enthalpy differences across equal temperature intervals. During phase transformation in both heating and quenching processes, there is an abrupt change observed in specific heat capacity. Confinement exerts a notable impact on entropy in the solid phase, but its influence is negligible in the liquid phase. At lower pore sizes (H < 25 Å), there is more fluctuation in freezing temperature for all wall-fluid interactions, which diminishes beyond pore sizes of H > 25 Å. Similarly, more oscillatory behavior is observed in melting temperatures at lower pore sizes (H < 40 Å), which diminishes at higher pore sizes (H > 40 Å). During the quenching process, a sudden jump in the in-plane orientational and tetrahedral order parameters indicates the formation of an ordered phase, specifically a diamond crystalline structure. The percentages of different crystalline structures (cubic diamond, hexagonal diamond, and 2D hexagonal) vary with both the confinement size and the wall-fluid interaction strength. Methods: Cooling and heating simulations are conducted with the mW water model using LAMMPS for different nanoscale confinement separation sizes ranging from 8.5 to 70 Å within the temperature range of 100–350 K. The water is modeled using two-body and three-body interaction potential (Stillinger–Weber potential) and the confinement is introduced using LJ 9–3 water-wall interaction potential. Entropy is calculated using RDF data obtained from the simulation experiments for each temperature point with increments or decrements of 2.5 K. The transition temperatures are estimated using the specific heat capacity analysis. [ABSTRACT FROM AUTHOR]

Bi‒Sr‒Ca‒Cu‒O polycrystalline high-temperature superconductors with the 2–2-2–3 structure have been comprehensively studied, their properties have been described, and features of the small magnetic hysteresis in the investigated materials have been established. The small magnetic hysteresis is shown to be caused by the penetration of a magnetic flux into a superconductor and its capture in the region of boundaries between HTS crystallites and by Meissner currents flowing through these boundaries. It has been found that, at a certain magnetic prehistory, the small hysteresis collapses, i.e. its footprints disappear. This has been attributed to the interaction between two superconducting subsystems in the investigated polycrystalline HTS, specifically, the effect of the magnetic moments of HTS crystallites on the effective field in the regions of intercrystalline boundaries. The shape of the small magnetic hysteresis loop has been described within the critical state model. [ABSTRACT FROM AUTHOR]

Barium hexaferrite (BaFe12O19) and Ni–Zn ferrite (Ni0.6Zn0.4Fe2O4) powders were synthesized using the microwave hydrothermal method. Composite samples with varying ratios {x(Ni0.6Zn0.4Fe2O4) + (1 − x) (BaFe12O19)} (where x ranged from 0 to 1.0) were prepared through mechanical mixing. The pure and composite samples were subjected to a 4-h heat treatment at 800 °C. The structural characteristics of the pure samples were analyzed using X-ray diffraction (XRD), revealing the hexagonal structure of BaFe12O19 and the spinel structure of Ni0.6Zn0.4Fe2O4. Morphological properties were investigated using field emission scanning electron microscopy (FESEM). The results confirmed a hexagonal morphology for BaFe12O19, a spherical morphology for Ni0.6Zn0.4Fe2O4, and a mixed morphology for the composites, with grain sizes ranging from 50 to 200 nm. The optical properties were explored through UV–Vis absorption studies, and the optical energy gap values were determined using the Tauc plots. The magnetic behavior of the samples was studied by analyzing magnetic hysteresis loops. Pure samples exhibited a smooth hysteresis behavior, while composite samples displayed a step-like pattern. A possible relation between the magnetic interaction between the two different materials in the composites was investigated. [ABSTRACT FROM AUTHOR]

The control of light through all‐optical means is a fundamental challenge in nanophotonics and a key effect in optical switching and logic. The optical bistability effect enables this control and can be observed in various planar photonic systems such as microdisk and photonic crystal cavities and waveguides. However, the recent advancements in flat optics with wavelength‐thin optical elements require nonlinear elements based on metastructures and metasurfaces. The performance of these systems can be enhanced with high‐Q bound states in the continuum (BIC), which leads to intense harmonic generation, improved light‐matter coupling, and pushes forward sensing limits. This study reports enhanced thermo‐optical nonlinearity and the observation of optical bistability in an all‐dielectric metasurface membrane with BIC. Unlike many other nanophotonic platforms, metasurfaces allow for fine control of the quality factor of the BIC resonance by managing the radiative losses. This provides an opportunity to control the parameters of the observed hysteresis loop and even switch from bistability to optical discrimination by varying the angle of incidence. Additionally, this work proposes a mechanism of nonlinear critical coupling that establishes the conditions for maximal hysteresis width and minimal switching power, which has not been reported before. The study suggests that all‐dielectric metasurfaces supporting BICs can serve as a flat‐optics platform for optical switching and modulation based on strong thermo‐optical nonlinearity. [ABSTRACT FROM AUTHOR]

The efficiency of a staged photocatalytic reactor prototype was evaluated on a semi‐pilot scale with the removal of acetaminophen, for which anatase particles were synthesized by Sol‐Gel and impregnated on rectangular plates of clay. X‐ray diffraction and Energy Dispersive X‐ray Fluorescence patterns show that the final composite is made up of Al2O3 (14 %), SiO2 (41 %), CaO (3 %) TiO2 (34 %), and Fe2O3 (7 %). The impregnation method favors the dispersion of Anatase on the surface of the adsorbent. TiO2‐Anatase/Clay, classified as a macro‐porous solid with H3‐type hysteresis loops by N2 physisorption. Adsorption processes are improved when using TiO2‐Anatase/Clay compared to using TiO2‐Anatase. The external mass transfer has a greater influence on the removal rate. The dimensionless parameters of the Biot number indicate there are no limitations due to the diffusive effect on the interior of the particle. The evaluation of the kinetic data under the Langmuir‐Hinshelwood equation shows a decrease in efficiency as the initial concentration increases. The acetaminophen molecule shows destabilization in the structure of the aromatic ring with a visible decrease in the signals of this functional group evaluated by High‐Performance Liquid Chromatography and Raman Spectroscopy. [ABSTRACT FROM AUTHOR]

This paper presents the results of an investigation of dynamic behaviours of strengthened adobe structures. These structures were strengthened using two different schemes which were inexpensive and simple to apply. The dynamic testing was carried out on a shaking table which applied the loading corresponding to the 1995 Kobe earthquake record sequentially in increments of 25%. The structural damage to a model was divided into different damage grades using a quantitative measure of vulnerability. Although some differences were observed in the stiffness of the models in their undamaged state, the stiffness of both of them became similar in the damaged state. The changes in the fundamental frequency of the structure corresponded to the changes in the stiffness. The difference in the base shear demand of both models did not exceed more than 15%. The hysteresis loops of the tested structures turned non-symmetric at a peak ground acceleration of nearly 1.10 g. The models exhibited higher lateral load capacities in one direction of loading as compared to the other direction. The ductility and energy dissipation were also higher in one direction of loading. The performance of the tested structures was categorised into four performance levels and the data of drift, ductility, damping and period corresponding to each level have been reported. [ABSTRACT FROM AUTHOR]

The recent discovery of sliding ferroelectricity opens up the field of 2D ferroelectricity. However, the limitation to switching the polarization due to the topological protection of the domain walls limits the potential of these heterostructures. Here, the switching of sliding ferroelectric bulk misfit layer compound (PbS)1.11VS2 crystals is studied using switching spectroscopy piezoresponse force microscopy. A large number of measured hysteresis loops can be efficiently analyzed using unsupervised machine‐learning tools. Different switching behavior of the domains is observed on different types of domain structures, and it is shown that full domain switching can be observed for the right type of dislocation structure in the PbS layer. [ABSTRACT FROM AUTHOR]

To investigate the impact of diverse multivariate mixing excitation conditions on the hysteresis loop of ferromagnetic materials, this study initially constructs a magnetic performance testing system for electrical steel. This system is capable of generating mixed excitation utilizing a standard Epstein square‐circle setup. Subsequently, the study measures the magnetic properties of the oriented silicon steel sheets at various mixing AC frequencies of the hysteresis loop data. Secondly, a hybrid network model integrating a convolutional neural network (CNN) and a bi‐directional long short‐term memory network (BiGRU), augmented with an attention mechanism (AM), is proposed and utilized for predicting the hysteresis properties of oriented silicon steel wafers subjected to compound mixed‐frequency excitation. The model utilizes CNN to extract high‐dimensional data features reflecting the hysteresis characteristics of the loop, BiGRU to capture the temporal evolution patterns of the key feature vectors, an AM to weigh the feature parameters and emphasize the key features, and a Bayesian optimization (BO) algorithm based on neural network hyperparameters for automatic selection, enhancing prediction accuracy. In comparison with experimental observations, the method accurately predicts material hysteresis properties under non‐sinusoidal complex excitation conditions, outperforming existing deep‐learning network models. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

A dual structural system for low-to-medium-rise buildings is examined, comprising light-timber frames (LTF) coupled with a cross-laminated timber (CLT) wall. To enhance the energy-dissipating capacity of LTF featuring pinching behavior, friction sheathing-to-frame connections have been proposed in place of conventional nail connectors. The resulting friction LTFs (FLTF) exhibit sustainably rich hysteresis loops that significantly enhance energy dissipation capacity. Nevertheless, the friction-dissipating mechanism leads to nonuniform story drift distributions and residual drifts in multistory FLTF buildings. To address this issue, a CLT wall with self-centering hold-down connections is coupled to the multistory FLTF building for imposing uniform story drifts and for reducing residual drifts. A direct displacement-based design (DDBD) approach is employed to design the dual CLT-FLTF system and ensure (i.e., impose) uniform seismic demand across the height of the building. Nonlinear-time-history analysis (NTHA) and incremental dynamic analysis (IDA) show that the DDBD approach can lead to safe designs and effectively control the displacements of the proposed dual system. [ABSTRACT FROM AUTHOR]

In the graphical abstract, we illustrate the innovative design of physical–chemical hybrid crosslinked composite hydrogels that exhibit a unique combination of properties, making them well-suited for advanced applications in flexible electronics and biosensing. These hydrogels demonstrate ideal stretchability and compressibility, alongside excellent adhesion capabilities. Their design is strategically tailored to ensure biocompatibility without compromising the sensitive detection of physiological signals. The graphical representation showcases the multifaceted nature of these materials, highlighting their dynamic responsiveness to mechanical stimuli and their potential to seamlessly interface with biological tissues for real-time monitoring and diagnostic purposes. [Display omitted] With the advancement of wearable and implantable medical devices, hydrogel flexible bioelectronic devices have attracted significant interest due to exhibiting tissue-like mechanical compliance, biocompatibility, and low electrical resistance. In this study, the development and comprehensive performance evaluation of poly(acrylic acid)/ N,N′-bis(acryloyl) cystamine/ 1-butyl-3-ethenylimidazol-1-ium:bromide (PAA/NB/IL) hydrogels designed for flexible sensor applications are introduced. Engineered through a combination of physical and chemical cross-linking strategies, these hydrogels exhibit strong mechanical properties, high biocompatibility, and effective sensing capabilities. At 95 % strain, the compressive modulus of PAA/NB/IL 100 reach up to 3.66 MPa, with the loading–unloading process showing no significant hysteresis loop, indicating strong mechanical stability and elasticity. An increase in the IL content was observed to enlarge the porosity of the hydrogels, thereby influencing their swelling behavior and sensing functionality. Biocompatibility assessments revealed that the hemolysis rate was below 5 %, ensuring their suitability for biomedical applications. Upon implantation in rats, a minimal acute inflammatory response was observed, comparable to that of the biocompatibility control poly(ethylene glycol) diacrylate (PEGDA). These results suggest that PAA/NB/IL hydrogels hold promise as biomaterials for biosensors, offering a balance of mechanical integrity, physiological compatibility, and sensing sensitivity, thereby facilitating advanced healthcare monitoring solutions. [ABSTRACT FROM AUTHOR]

Recent years, the polarization response of ferroelectrics has been entirely studied. However, it is found that the polarization may disappear gradually with the continually applied of electric field. In this paper, taking K0.48Na0.52NbO3(KNN) as an example, it was demonstrated that the residual polarization began to decrease when the electric field frequency increased to a certain extent using a phase-field methods. The results showed that the content of out-of-plane domains increased first and then decreased with the increase of applied electric field frequency, the maximum polarization disappeared at high frequencies, and the hysteresis loop became elliptical. In order to further study the abnormal changes of hysteresis loops of ferroelectrics under high electric field frequency, we analyzed the hysteresis loop and dielectric response of solid solution 0.1SrTiO3-0.9K0.48Na0.52NbO3. It was found that the doped hysteresis loop maintained its shape at higher frequency and the dielectric constant increased. This kind of doping has a higher field frequency adaptability, which has a key guiding role in improving the dielectric properties of ferroelectric thin films and expanding the frequency application range of ferroelectric nano memory. [ABSTRACT FROM AUTHOR]

Nanostructured Fe90Si10 powders were synthesized through a mechanical alloying process to explore the impact of milling duration on both their magnetic behavior and structural properties. Our investigation involved a comprehensive analysis encompassing morphological, magnetic, and structural characterizations, employing scanning electron microscopy (SEM) coupled with energy-dispersive x-ray spectroscopy (EDS), a vibrating sample magnetometer, and x-ray diffraction (XRD). XRD analysis unveiled the formation of a disordered Fe90Si10 solid solution exhibiting a body-centered cubic crystal structure after 15 h of milling. With increasing milling time, the lattice parameter gradually increased from 0.2861 nm for the unmilled Fe90Si10 powder to 0.4528 nm after 30 h of milling. The sample subjected to 30 h of milling revealed an average crystallite size of 19.51 ± 0.03 nm, accompanied by noteworthy lattice deformation (0.236 ± 0.006%). To assess morphological evolution and elemental composition homogeneity during milling, SEM and EDS analyses were employed, respectively. For nanostructured Fe90Si10, we examined coercivity (Hc), magnetization saturation (Ms), remanent magnetization (Mr), and squareness (Mr/Ms) as functions of milling time through hysteresis loop measurements. The highest values for Hc, Ms, Mr, and Mr/Ms were achieved after 30 h. This study elucidates the intricate relationship between mechanical milling duration and the magnetic and structural properties of nanostructured Fe90Si10, providing valuable insights into their potential applications across various fields. [ABSTRACT FROM AUTHOR]

Lead‐free ceramic capacitors with high energy storage density are desired. Herein, the novel (1–x)(0.9Bi0.5Na0.5TiO3‐0.1SrTi0.85Zr0.15O3)‐xNa0.95Ca0.04Li0.01Nb0.96Zr0.04O3 [(1–x)(BNT‐STZ)‐xCZNNL, x = 0.1, 0.2, 0.3, 0.4 and 0.5] ceramics are prepared via citrate combustion technology and two‐step sintering method. The dense microstructures are observed and slim hysteresis loops are realized as addition of CZNNL. The enhanced recoverable energy storage density (Wre of 2.52 J cm−3) with high efficiency (η of 80%) is obtained in 0.6(BNT‐STZ)‐0.4CZNNL ceramic under a moderate electric field of 200 kV cm−1. Moreover, excellent thermal stability (Wre varies <1% and η varies <3.5%) at 20 to 100 °C) and excellent fatigue resistance are achieved for 0.6(BNT‐STZ)‐0.4CZNNL ceramic. [ABSTRACT FROM AUTHOR]

Bismuth Layer-Structured Ferroelectric (BLSF) materials with Bi 4 Ti 3 O 12 composition exhibit high ferroelectricity, potential for high-temperature piezoelectricity, and the puzzle of low polarizability, explored via textured ceramics and domain configurations. Here, we show that a distinctive stripe configuration of 90° domains emerges for large platelet-like grains, while the smallest grains, possessing a more equiaxial morphology, exhibit a needle-like domain structure that significantly impacts the ferroelectric properties of the ceramics. The observed hysteresis loops suggest that polarization is effectively clamped, owing to reduced mobility along the needle-like domain walls, thereby leading to a reduction in remnant polarization as grain size diminishes. It is elucidated that the domain structure is intricately linked to both internal stress within the grains and the presence of defects, notably oxygen vacancies, at the domain walls. Consequently, these multifaceted factors are identified as key determinants of the ferroelectric activity within ceramics bearing such a distinctive crystalline structure. [Display omitted] • Confocal Raman Microscopy reveals detailed domain structures in BLSF ceramics. • Grain morphology, domain structures, and internal stresses dictate polarization behavior. • Large platelet-like grains exhibit distinctive 90° stripe domain configuration. • Smallest equiaxial grains show impactful needle-like domain structure. • Reduced grain size leads to clamped polarization, diminishing remnant polarization. [ABSTRACT FROM AUTHOR]

Lead‐free ceramic capacitors with high energy storage density are desired. Herein, the novel (1–x)(0.9Bi0.5Na0.5TiO3‐0.1SrTi0.85Zr0.15O3)‐xNa0.95Ca0.04Li0.01Nb0.96Zr0.04O3 [(1–x)(BNT‐STZ)‐xCZNNL, x = 0.1, 0.2, 0.3, 0.4 and 0.5] ceramics are prepared via citrate combustion technology and two‐step sintering method. The dense microstructures are observed and slim hysteresis loops are realized as addition of CZNNL. The enhanced recoverable energy storage density (Wre of 2.52 J cm−3) with high efficiency (η of 80%) is obtained in 0.6(BNT‐STZ)‐0.4CZNNL ceramic under a moderate electric field of 200 kV cm−1. Moreover, excellent thermal stability (Wre varies <1% and η varies <3.5%) at 20 to 100 °C) and excellent fatigue resistance are achieved for 0.6(BNT‐STZ)‐0.4CZNNL ceramic. [ABSTRACT FROM AUTHOR]

In this work, we use molecular dynamics simulations to investigate the switching behavior of BaTiO3 ferroelectric under the application of a high-amplitude high-frequency oscillatory electric field. While at lower frequencies, we observe a standard square-shaped hysteresis loop behavior, at frequencies approaching 1 THz, the hysteresis loop has an ellipsoidal shape. As the frequency increases, the average polarization oscillates without switching direction. To elucidate the origin of the ∼1 THz limit for the polarization switching, we analyzed unit-cell-level polarization vector maps. In this context, the analysis of the low-frequency switching events revealed that in addition to the majority of the polarization vectors exhibiting rapid switching, some "metastable" aligned polarization vectors persist longer with an average lifetime of ∼1 ps. As the frequency increases to the THz range, several polarization vector lines remain unswitched, thus preventing the polarization switching at the simulation domain level. Furthermore, we observe that with the increase in the amplitude of the applied electric field, one can increase the frequency at which switching is observed. [ABSTRACT FROM AUTHOR]

The dielectric gap between the scanning probe microscopy (SPM) tip and the surface of a ferroelectric using conductive atomic force microscopy and piezoresponse force microscopy (PFM) is investigated. While the gap functions as a dielectric layer, it also allows tunneling current to inject charges into the ferroelectric when a critical loading force between 10–20 µN is applied to a tip with a radius of 25 nm under a bias voltage of 0.5 V. It is observed that the permittivity of the dielectric gap determines the coercive voltage measured by the piezoresponse hysteresis loop. While such studies done in air often produce coercive voltages much larger than those studied for the same materials in capacitor‐based studies, the use of high permittivity media such as water (ɛr = 79) or silicone oil (ɛr = 2.1‐2.8) produces coercive fields that more closely match those measured in conventional capacitor‐based polarization hysteresis loop measurements. Furthermore, using water as a dielectric medium in PFM imaging enhances the accuracy in extracting the amplitude and phase data from periodically poled lithium niobate crystals. These findings provide insight into the nanoscale phenomena of polarization switching instigated by the SPM tip and provide a pathway to improved quantitative studies. [ABSTRACT FROM AUTHOR]

In this work, we use molecular dynamics simulations to investigate the switching behavior of BaTiO3 ferroelectric under the application of a high-amplitude high-frequency oscillatory electric field. While at lower frequencies, we observe a standard square-shaped hysteresis loop behavior, at frequencies approaching 1 THz, the hysteresis loop has an ellipsoidal shape. As the frequency increases, the average polarization oscillates without switching direction. To elucidate the origin of the ∼1 THz limit for the polarization switching, we analyzed unit-cell-level polarization vector maps. In this context, the analysis of the low-frequency switching events revealed that in addition to the majority of the polarization vectors exhibiting rapid switching, some "metastable" aligned polarization vectors persist longer with an average lifetime of ∼1 ps. As the frequency increases to the THz range, several polarization vector lines remain unswitched, thus preventing the polarization switching at the simulation domain level. Furthermore, we observe that with the increase in the amplitude of the applied electric field, one can increase the frequency at which switching is observed. [ABSTRACT FROM AUTHOR]

The influence of size on the dynamic magnetic hysteresis properties and dynamic phase transitions of Fe and F e 3 O 4 2D-circular nanodisks with varying diameters has been explored in the micromagnetic framework. This investigation is conducted under a sinusoidal dynamic magnetic field along the x-direction by solving the Landau-Lifshitz-Gilbert (LLG) equation with the OOMMF software at zero temperature. The dynamic hysteresis of nanodisks is profoundly impacted by both the frequency and amplitude of the applied external field, along with the particle size. As particle size decreases, there is an observed increase in the frequency values at which the transition to dynamic ordered frequency occurs in Fe nanodisks, whereas a decrease is noted in the transition frequency values of F e 3 O 4 nanodisks. [ABSTRACT FROM AUTHOR]

In this work, three simple configurations of meminductor mutator are presented. The first two configurations of meminductor mutator have been implemented utilizing one CMOS-based operational amplifier, one memristor, one capacitor, and five resistors, while the third configuration of meminductor mutator is implemented utilizing one CMOS-based operational amplifier, two memristors, one capacitor, and four resistors. The implementation and simulation of the proposed configurations are done by using LTspice tool. The viability of the proposed circuits is demonstrated by utilizing TSMC 180 nm CMOS technology parameters. The proposed circuits of the meminductor have a simple structure in contrast to many of the circuits presented in the literature and operate satisfactorily over a wide range of frequencies. The functionality of the proposed circuits is verified through utilization of both the spice model of memristor and a memristor emulator circuit. A chaotic oscillator and second-order high pass filter are designed using the proposed meminductor to verify its workability. [ABSTRACT FROM AUTHOR]

In the present study, we report a significant magnetoelectric coupling in lead-free (1-x)Ba0.95Ca0.05Ti0.95Sn0.05O3 - (x)Ni0.7Zn0.3Fe2O4 (x = 0.10, 0.15, 0.20, 0.25 and 0.30) particulate composites prepared by solid-state route. Phase purity and crystal structure of the composites were examined by the X-ray diffraction measurement. With the incorporation of the magnetic NZFO phase, a decrease in the tetragonality of the ferroelectric BTCS lattice was confirmed by the full pattern match of the XRD data using Rietveld analysis. FESEM micrographs revealed improved microstructures with the addition of ferrite concentrations in the composites. Simultaneous presence of ferroic orders in the composites was confirmed from the room-temperature P-E and M-H hysteresis loops. Direct magnetoelectric voltage measurement of the composites established the strain-mediated coupling between the BTCS and NZFO phases. Highest RT first-order magnetoelectric voltage coefficient (α/d = 6.24 mV/cm-Oe) of the x = 0.25 composite is attributed to better individual ferroic properties and improved microstructure of this sample. [ABSTRACT FROM AUTHOR]

Snowmelt erosion and rainfall erosion are important components of soil erosion in Northeast China. Studying how snowmelt and rainfall affect runoff and sediment yield is essential to control soil erosion in this region. Based on the soil and water loss observation data in small watershed during snowmelt and rainfall periods, snowmelt and rainfall erosion processes were studied. The runoff–sediment relationship was analyzed. The results indicate that 13 snowmelt runoff events and 14 rainfall runoff events were recorded. During the snowmelt period, runoff depth (RD) and sediment yield (SY) exhibited a slow increase (early stage), rapid increase (middle stage), and then rapid decrease (late stage) trend. RD and SY in the middle stage were higher than those in the early and late stages. Moreover, during the rainfall period, soil erosion mainly occurred from July to August; during these two months, the rainfall and rainfall erosivity accounted for 66.0 and 91.1% of the total rainfall and rainfall erosivity, respectively; and the RD and SY in this period accounted for 88.4 and 89.8% of total amounts in the whole rainfall period, respectively. In addition, the contributions of snowmelt and rainfall to RD and SY were 18.6 and 81.4%, and 3.8 and 96.2%, respectively. Hysteresis analysis suggested that clockwise hysteresis loop was the dominant pattern, followed by eight-shaped anticlockwise loop, and complex anticlockwise loop. [ABSTRACT FROM AUTHOR]

Harnessing low ultrasonic vibration energy to initiate piezocatalytic-based reactions is increasingly becoming a significant focus due to the current environmental energy crisis. In this study, we report on the potential of heterovalent ion substitution in improving piezocatalytic degradation of Rhodamine B dye (RhB) under the application of low-power ultrasonic vibration. For this purpose, bismuth ions Bi3+ are substituted into the lead-free ferroelectric BaTi 0 · 89 Sn 0 · 11 O 3 (BTSn 11 -xBi, x = 0, 0.02, 0.04) submicrocubes synthesized using sol-gel method. The structural, morphological, optical and piezocatalytic properties of the prepared materials appear to be significantly influenced by the substituting content. Compared to pure BTSn 11 and BTSn 11 -0.04Bi, BTSn 11 -0.02Bi exhibits the lowest band gap energy value of 3.22 eV, the smallest particle size value of 283 nm, the strongest piezoelectric current of about 8 μA/cm2, and the lowest required applied field for piezoresponse force microscopy hysteresis loops. The degradation efficiency and the kinetic rate constant are substantially higher for BTSn 11 -0.02Bi, indicating its enhanced piezocatalytic efficiency. Total organic carbon (TOC) measurements revealed good RhB mineralization using BTSn 11 -xBi piezocatalysts. Furthermore, the BTSn 11 -0.02Bi sample demonstrates good reusability and stability by maintaining effective RhB dye degradation for five consecutive cycling tests. These findings suggest that the BTSn 11 -0.02Bi piezocatalytic system holds significant potential for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Nowadays, there is a global search for electromagnetic gadgets that are affordable, eco-friendly, and energyefficient. This motivates engineers and scientists to develop new materials or enhance those that already exist. Fe-based soft magnetic materials are a significant class of soft magnetic materials that are essential to many energy-related industrial applications, including motors, converters, and electric transformers. This article focuses on the general characterization of magnetic materials, their magnetic properties and the analysis of the influence of mechanical milling of Fe powders prepared by mechanical milling in two different sizes (sample 1 - smaller then < 400 µm and sample 2 greater than > 400 µm). The experimentally obtained hysterical curves of ground Fe powders are measured using the Vibratimg Sample Magnetometer (VSM). [ABSTRACT FROM AUTHOR]

In this work, a current and magnetic field sensor is proposed and experimentally demonstrated utilizing a fiber-optic Mach–Zehnder interferometer (MZI) structure. In our setup, one of the interferometer arms is coated with magnetic nanoparticles. The MZI comprises a laser source emitting an optical signal, split by a coupler into two signals propagated by a reference fiber and a sensor fiber. The sensing fiber is encased in cobalt ferrite (CoFe2O4). Upon exposure to a magnetic field, CoFe2O4 induces vibration in the fiber, modifying the sensor's transmission and causing an imbalance between the optical signals of the interferometer arms. This enables us to evaluate the sensor performance regarding sensitivity, accuracy, and saturation. The nanoparticles were synthesized using the protein sol–gel method, resulting in an average crystallite size of 8, 27, and 67 nm for 623, 773, and 1073 K, respectively. Sample characterizations were conducted through X-ray fluorescence, X-ray diffraction, VSM magnetic measurements, and Mössbauer spectroscopy for further analysis of the performance. The sensor exhibited a linear response, achieving a maximum regression between 93.0% and 98.6% across all sample points in the 0 to 150 Oe range, with an output power of approximately 20 dBm, correlated with the applied magnetic field. Sensitivity was measured at 1.15, 0.93, and 1.41 dB/Oe. Previous studies have correlated the horizontal width of the hysteresis loop with sensor saturation. However, by employing a different coating in this work, we complement these findings by demonstrating that the sensor does not saturate if the maximum applied field is smaller than the hysteresis loop width. [ABSTRACT FROM AUTHOR]

The presented study investigates the dynamics of DOC concentrations in headwater peatbog areas with respect to the extreme rainfall-runoff (R-R) events hydrometeorological catchment preconditions (23 variables in total). The main data sources were automatic devices for monitoring of groundwater level, discharges and rainfalls providing data in 10 min steps installed in the Vydra River catchment and one automatic water sampler ISCO in sub-catchment of the Rokytka River basin in the Šumava (Bohemian Forest) National Park. The study period was 2018–2021, in which 18 R-R events were analysed. Data of DOC variability and catchment conditions were analysed using Spearman's correlation coefficient, Principal Component Analysis and DOC/Q hysteresis loops. Changes in groundwater level and discharges had the greatest influence on DOC concentrations. Higher mean and maximum DOC were measured during events after a longer period without an extreme R-R event. The greater lag time of maximum DOC after peak flow and the higher mean DOC during the event were primarily due to hydrometeorological preconditions of the catchment. The highest DOC was in autumn after the previous summer period with low discharges and low groundwater levels. DOC was also positively correlated with air and water temperatures. [ABSTRACT FROM AUTHOR]

In recent years, polymers have been popular in industrial applications due to their lightweight, corrosion‐resistant, improved surface polish, ease of manufacturing, cost‐effectiveness, and so forth. Similarly, micro/nano‐indentation has gained popularity as a technique for assessing the surface mechanical characteristics of polymers. The present study conducted comprehensive experiments using cyclic micro‐indentation on engineering polymers, specifically poly‐ether‐ether‐ketone (PEEK), poly(methyl methacrylate) (PMMA), and poly(tetra‐fluoroethylene) (PTFE). An appropriate and optimal indentation method has been proposed after analyzing the behavior and significance of all the input parameters in evaluating the properties. Both constant load multi‐cycle (CLMC) and progressive load multi‐cycle (PLMC) were considered for this investigation. A comparative evaluation has been conducted to assess two multi‐cycle tests on these materials. From the analysis of the input parameters, including maximum loads, loading and unloading rates, and the number of cycles, the unloading rate and indentation cycle are crucial factors in determining hardness (H) and elastic modulus (E). Increasing the loading rates leads to an increase in H and a reduction in E for all three materials. This effect arises from the thermal effect, which is characterized by the creep modulus and a closed hysteresis loop. Employing the holding duration and multiple cycle data in constant load multi‐cycle can significantly influence the creep behavior and use of the hysteresis loop for fatigue behavior. Similarly, a progressive load multi‐cycle indentation with a force greater than 0.5 N and a minimum of five cycles is the most accurate approach for evaluating surface mechanical parameters. [ABSTRACT FROM AUTHOR]

We reported the new synthesis of Sm2Co17 particles by a microwave-assisted combustion (MACS) method. This process enables the controlled decomposition of Sm(NO3)3 and Co(NO3)2 into SmCo-O particles, followed by calcium reduction-diffusion. This SmCo-O particle provides an approach for achieving high magnetic properties in Sm2Co17 magnetic materials. The rhombohedral Sm2Co17 particles can be incorporated into epoxy resin and oriented, displaying a square-like hysteresis loop. The particles display magnetic properties at room temperature, with a saturation magnetization of 112.3 emu/g, coercivity of 5.6 kOe, and a maximum energy product of 9.4 MGOe. This method improves the synthesis efficiency of rare earth cobalt-based nano-materials, expands the synthesis scope, and provides ideas for the synthesis and applications of other rare earth nano-materials. [ABSTRACT FROM AUTHOR]

The distinctly shaped steel-reinforced concrete (SRC) column–beam framing system offers an innovative and tailored structural solution that combines load-bearing capabilities with architectural esthetics. This study introduces an innovative joint design methodology, focusing on examining the seismic responsiveness of the uniquely designed SRC columns when interconnected with reinforced concrete (RC) beams, subjected to bidirectional low cycle loading patterns through precisely calibrated pseudo-static evaluations with varied stirrup spacing. A comparative assessment was undertaken, comparing the joints of SRC test specimens with their RC counterparts, ensuring equivalency in steel and reinforcement area to maintain fairness. The evaluation encompassed a thorough examination of hysteresis loop backbone curves, as well as load–strain hysteresis patterns. It was found that the specimens incorporating structural steel and tubes demonstrated enhanced energy dissipation capabilities, surpassing other specimens in this critical performance aspect. An in-depth analysis was also conducted by comparing the ductility coefficient and the equivalent viscous damping coefficient to evaluate the joints' performance in dissipating energy, coupled with a thorough examination of their stiffness deterioration behavior. The conclusion is that the energy dissipation capacity and stiffness degradation of distinctly shaped SRC column joints are superior to those of conventional, distinctly shaped concrete column joints, indicating promising application prospects. [ABSTRACT FROM AUTHOR]

The dielectric properties of a mixed Zethrene-inspired nanoscale system ( S i Z -1, σ k Z -5/2) have been analyzed in detail using the Monte Carlo approach (MCa) in this study. First, the most stable configurations in different planes were investigated. Then, the influences of the physical factors, namely the coupling interaction factor, on the thermal behaviors of the polarization and the susceptibility of the studied nanostructure have been examined for nonzero temperatures and fixed external electric field values. It was found that the obtained transition temperature point relies weakly on the coupling interaction. Finally, the effects of the physical factors on the electric hysteresis cycles were discussed. [ABSTRACT FROM AUTHOR]