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To precisely investigate the electric properties and reveal the intrinsic interaction mechanisms between multiple fields in the composite magneto-electric-semiconductor shell structure, two-dimensional analyses were conducted within the framework of the third-order shear deformation theory and the coupled field theory. The governing equations for the composite piezoelectric semiconductor (PS) shell structures were derived using the principle of virtual work. Field distributions of the composite PS shell structures were obtained by expanding basic field quantities into Fourier series along the width direction and using the differential quadrature method. Prior to analysis, the convergence and correctness of the adopted method were evaluated. Several numerical examples were presented to demonstrate how magnetic manipulation can tune electrical behavior. It was found that inhomogeneous shear strain induced by applied magnetic fields is the key factor affecting potential variation in the composite PS shells. The appearance of potential barriers and wells in the composite PS shell structure with an opposite c axis is explained thoroughly. Additionally, the effect of magnetic field non-uniformity on the composite PS shell structure was investigated using an equivalent body force model, offering valuable insights for designing thin-film devices. [ABSTRACT FROM AUTHOR]

Micromagnetic simulations are used to investigate the effect of an external magnetic field on the interaction between domain walls and linearly polarized propagating spin waves in synthetic antiferromagnets. Two regimes with a sharp transition between them are found. At large fields, spin waves are strongly reflected by the domain wall and, consequently, the latter is propelled forward. At low fields, however, there is no reflection and yet the domain wall undergoes a small forward displacement, which is attributed to the change in linear momentum of the magnons as they pass through the domain wall and to the imbalance in the population of the two oscillation modes present in the linearly polarized excitation. The transition between the two regimes occurs at the field value for which the excitation frequency falls below the threshold of the high-frequency mode. [ABSTRACT FROM AUTHOR]

This paper introduces a spin-free formulation of the supporting subspace factorization [C. Song and T. J. Martínez, J. Chem. Phys. 149, 044108 (2018)], enabling a reduction in the computational scaling of the extended multi-state complete active space second-order perturbation (XMS-CASPT2) method for arbitrary spins. Compared to the original formulation that is defined in the spin orbitals and is limited to singlet states, the spin-free formulation in this work treats different spin states equivalently, thus naturally generalizing the idea beyond singlet states. In addition, we will present a new way of deriving the supporting subspace factorization with the purpose of understanding its physical interpretation. In this new derivation, we separate the sources that make CASPT2 difficult into the "same-site interactions" and "inter-site interactions." We will first show how the Kronecker sum can be used to remove the same-site interactions in the absence of inter-site interactions, leading to MP2 energy in dressed orbitals. We will then show how the inter-site interactions can be exactly recovered using Löwdin partition, where the supporting subspace concept will naturally arise. The new spin-free formulation maintains the main advantage of the supporting subspace factorization, i.e., allowing XMS-CASPT2 energies to be computed using highly optimized MP2 energy codes and Fock build codes, thus reducing the scaling of XMS-CASPT2 to the same scaling as MP2. We will present and discuss results that benchmark the accuracy and performance of the new method. To demonstrate how the new method can be useful in studying real photochemical systems, the supporting subspace XMS-CASPT2 is applied to a photoreaction sensitive to magnetic field effects. The new spin-free formulation makes it possible to calculate the doublet and quartet states required in this particular photoreaction mechanism. [ABSTRACT FROM AUTHOR]

The advancement of magnetic materials with coupled magneto-structural phase transition (MST) to fulfill the ultimate objectives of practical solid-state cooling applications requires a better understanding of the hysteresis phenomenon linked across the phase transition region along with the large magnetocaloric parameters. For the present sample Mn0.65Ni0.65Fe0.70Si, the MST is associated with a sharp jump in magnetization along with a small thermal hysteresis of ∼13 K. A giant isothermal magnetic entropy change (| Δ S M max |) of ∼37.6 J kg−1 K−1 at 299 K and effective refrigerant capacity (R C effe ) of ∼214.3 J kg−1 under ΔH = 30 kOe is obtained with excellent compatibility between the martensite and austenite phases. The geometrical compatibility condition, i.e., very small (∼0.55%) deviation of the middle eigenvalue (λ 2) from unity justifies the observation of small hysteresis in the present material. The investigation of hysteresis behavior under different extents of the driving forces (temperature or magnetic field) reveals that both the driving forces trigger equally the phase transition and are responsible equivalently for the hysteresis phenomenon. The present study provides a pathway to understand the complexity of the hysteresis behavior, its impact on the reversibility of magnetocaloric effect, and its minimization by optimizing the geometrical compatibility condition between the austenite and martensite phases. [ABSTRACT FROM AUTHOR]

Magnetically ordering media support spin waves or magnons, which can couple with electromagnetic waves to form magnon polaritons. Based on insulating antiferromagnets, magnon polaritons are situated in the far-infrared or THz frequency range. We investigated Dyakonov surface magnon polaritons (DSMPs) at the antiferromagnetic surface in an external magnetic field, where the external field and antiferromagnetic easy axis lie in the surface plane and are normal to each other. Our numerical results are based on the MnF2 crystal, but the conclusions and qualitative results are also available to other insulating antiferromagnets. We predicted two field-tunable DSMPs and one tunable Dyakonov surface magnon. We discerned the main effects of the external magnetic field on the DSMPs; either DSMPs are sensitively modulated by the external field or there is a cutoff magnetic field. Their individual Poynting vector seriously deviates the propagation direction and is sensitively controlled by the external field. The spin angular momentum contains two components normal to each other, unlike conventional surface magnon polaritons. One of the DSMPs can carry a huge Poynting vector and spin angular momentum in the external magnetic field. These results are interesting for micromechanics and spintronics and relevant technologies in the far-infrared or THz domain. [ABSTRACT FROM AUTHOR]

Electromagnetohydrodynamic (EMHD) flow in porous media is recently gaining substantial attention from researchers. EMHD involves analyzing the combined effects of electric and magnetic fields on the behavior of fluid flow through a medium. The effective permeability of porous materials is of great interest for many environmental and industrial applications. The present study focuses on the modeling of single-phase fluid flow in porous media under combined effects of electric and magnetic fields at the pore scale by employing a two-scale computational homogenization technique. The primary objective of this study is to establish a definition of "electromagnetopermeability" that accurately characterizes the effective permeability of a porous medium under the EMHD effects. Additionally, the study investigates the impact of wall zeta potential, Debye length, and the intensity of external magnetic and electric fields, represented by the Hartmann number and the non-dimensional parameter S, respectively, on the electromagnetopermeability tensor within an idealized three-dimensional periodic porous domain. It is observed that the EM-permeability is significantly affected by the existence of the flow-assisting and flow-opposing components of the Lorentz force term in the momentum equation. The implications of this research extend to several industries, including geology, medicine, chemistry, and energy conversion. [ABSTRACT FROM AUTHOR]

A one-dimensional implicit particle-in-cell/Monte Carlo collision simulation was employed to study the effects of a uniform weak magnetic field and negative direct-current (DC) voltage on a radio frequency capacitively coupled plasma (CCP). The simulation results indicate that the application of a magnetic field to RF/DC hybrid power-driven CCP discharge can increase the plasma density and cause it to exhibit an asymmetric distribution. When the magnetic field strength increases, pronounced striations can be observed within the DC sheath in the spatiotemporal plots of an electron heating rate and an ionization rate. This is attributed to the generation of a large number of secondary electrons by the DC electrode. These secondary electrons are accelerated by the sheath voltage and undergo E × B drift motion. When the energy of these electrons reaches the ionization threshold of an argon gas, ionization occurs. At this point, the electrons are still situated within the DC sheath, and hence, they repeatedly undergo this process until they exit the DC sheath. Additionally, the electron energy distribution function reveals that an increase in a magnetic field can cause a transition from stochastic heating to ohmic heating. The simulation results of magnetized CCP discharge under the influence of negative DC voltage show that increasing negative DC voltage can effectively improve plasma density. The application of negative DC voltage and magnetic field strength has similar effects on the heating stripe phenomenon. As the negative DC voltage increases, the striation phenomenon becomes more pronounced. [ABSTRACT FROM AUTHOR]

Understanding and modulating the spin-pair correlation of conjugated polymer materials in π-conjugated polymer light-emitting devices (PLEDs) plays a crucial role in the development of their applications. We investigated the relationships between the internal hyperfine interactions (HFIs), triplet–triplet annihilation (TTA), and triplet–charge annihilation (TCA) spin evolution processes in π-conjugated PLED. Research has shown that in a unipolar π-conjugated PLED, the "M" shaped ultra-small magnetic field effect is due to the HFI between hole polarons and the spin-mixing process of charge carriers. Under high magnetic fields (15 mT<|B|<350 mT), the TCA process dominates the negative magneto-conductance (MC), and its intensity and sign are not controlled by temperature. In polar π-conjugated PLED, excess carriers can provide conditions for the generation of TCA. Moreover, π-conjugated polymers (emission layers) have relatively strong electron–phonon coupling, which can capture triplet excitons into adjacent organic layers to obtain higher triplet exciton concentrations, resulting in the TTA process. Under low-temperature conditions, excess carriers induce the magneto-electroluminescence (MEL) effect to undergo TTA and form P-type delayed fluorescence. This study can provide a new mechanism explanation for the HFI in PLED devices and a new approach for the effective utilization of triplets. [ABSTRACT FROM AUTHOR]

The operating bandwidth of miniaturized magnetoelectric (ME) antenna is generally narrow due to the acoustic wave driven magneto-electromechanical resonance effect, parallel connection of multiple ME antennas with different resonant frequencies is an effective way to broaden the operating bandwidth of the antenna. This paper presents an ME antenna array consisting of three units, which are constructed of a sandwich stack of Metglas/Pb(Mg1/3Nb2/3)O3–PbTiO3/Metglas. The −3 dB operating bandwidth of 152.4–172.8 kHz is achieved, and the relative bandwidth is 12.5%. Experimental results indicated that the bias magnetic field and coupling effect between the ME antenna units significantly influence the performance of ME antenna array. A modified Butterworth–Van Dyke (MBVD) equivalent circuit model is used and improved to analyze the influence of sound waves, electric fields, magnetic fields, parasitic capacitance, and bias magnetic field on the ME antenna array. The simulation results of the MBVD equivalent circuit model are agreed well with the experimental results. The improved MBVD model is beneficial for the design of acoustic wave driven antenna array. [ABSTRACT FROM AUTHOR]

Cryptochrome 4a (Cry4a) has been proposed as the sensor at the heart of the magnetic compass in migratory songbirds. Blue-light excitation of this protein produces magnetically sensitive flavin–tryptophan radical pairs whose properties suggest that Cry4a could indeed be suitable as a magnetoreceptor. Here, we use cavity ring-down spectroscopy to measure magnetic field effects on the kinetics of these radical pairs in modified Cry4a proteins from the migratory European robin and from nonmigratory pigeon and chicken. B1/2, a parameter that characterizes the magnetic field-dependence of the reactions, was found to be larger than expected on the basis of hyperfine interactions and to increase with the delay between pump and probe laser pulses. Semiclassical spin dynamics simulations show that this behavior is consistent with a singlet–triplet dephasing (STD) relaxation mechanism. Analysis of the experimental data gives dephasing rate constants, rSTD, in the range 3–6 × 107 s−1. A simple "toy" model due to Maeda, Miura, and Arai [Mol. Phys. 104, 1779–1788 (2006)] is used to shed light on the origin of the time-dependence and the nature of the STD mechanism. Under the conditions of the experiments, STD results in an exponential approach to spin equilibrium at a rate considerably slower than rSTD. We attribute the loss of singlet–triplet coherence to electron hopping between the second and third tryptophans of the electron transfer chain and comment on whether this process could explain differences in the magnetic sensitivity of robin, chicken, and pigeon Cry4a's. [ABSTRACT FROM AUTHOR]

The concept of building logically functional networks employing spintronics or magnetic heterostructures is becoming more and more popular today. Incorporating logical segments into a circuit needs physical bonds between the magnetic molecules or clusters involved. In this framework, we systematically study ultrafast laser-induced spin-manipulation scenarios on a closed system of three carbon chains to which three Ni atoms are attached. After the inclusion of spin–orbit coupling and an external magnetic field, different ultrafast spin dynamics scenarios involving spin-flip and long-distance spin-transfer processes are achieved by various appropriately well-tailored time-resolved laser pulses within subpicosecond timescales. We additionally study the various effects of an external magnetic field on spin-flip and spin-transfer processes. Moreover, we obtain spin-dynamics processes induced by a double laser pulse, rather than a single one. We suggest enhancing the spatial addressability of spin-flip and spin-transfer processes. The findings presented in this article will improve our knowledge of the magnetic properties of carbon-based magnetic molecular structures. They also support the relevant experimental realization of spin dynamics and their potential applications in future molecular spintronics devices. [ABSTRACT FROM AUTHOR]

In this research, the combined effect of magnetohydrodynamics (MHD) and slip velocity on squeeze film lubrication of long cylinders and infinite plates with couple stress fluid has been studied. Combining the Stokes couple stress theory and the Lorentz force theory yields analytical solutions for the modified Reynolds equation. Using the Reynolds equation, the mathematical expressions for squeeze film pressure, load-carrying capacity and squeeze film time are obtained. The pressure, load carrying capacity and squeeze film time increase with the combined effect of MHD, couple stress fluids and slip velocity. [ABSTRACT FROM AUTHOR]

This study delves into the exploration of hybrid nanofluids within the context of a stretching cylinder, a domain that has captivated numerous researchers owing to its pivotal applications in industrial manufacturing processes, particularly in metal forming and stretch dies. The authors, recognizing the significance of these applications, have introduced a novel heat transfer fluid termed hybrid nanofluid, comprising molybdenum disulfide and carbon nanotubes suspended in the base liquid, water. The investigation focuses on the flow of the hybrid nanofluid within a stretching cylinder, considering various influential factors such as Joule heating, thermal radiation, porous medium, and magnetic field effects. To model this complex problem, we employed modified Navier–Stokes equations. Employing similarity transformations, assumptions, and non-dimensional parameters, the problem was effectively simplified. The MATLAB bvp4c technique, a well-established numerical approach, was then employed to solve the resulting mathematical formulation. Graphical representations are presented to illustrate various aspects of the flow, facilitating a comprehensive understanding of the system. Comparisons are drawn among the flow characteristics of mono nanofluid, and the developed hybrid nanofluid. It is noted from the current analysis that the temperature strength increases with higher values of the magnetic field parameter, curvature parameter, radiation parameter, and Eckert number in both fluid cases. The Nusselt number increases with higher values of Prandtl number and thermal relaxation parameter. The identified patterns in velocity distribution, temperature strength, and fluid behavior provide a valuable foundation for optimizing thermal efficiency in diverse industrial applications. By leveraging the insights gained from this research, manufacturers can make informed decisions to enhance heat transfer processes, particularly in areas such as metal forming and stretch dies. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical analysis of the effects of a magnetic field, couple stress fluid, and slip velocity on squeeze film lubrication between a sphere and a flat plate. The modified Reynolds equation is derived using Stokes micro continuum theory of couple stress fluids. The nondimensional governing equations of the flow model are solved analytically for pressure, load-carrying capacity and squeezing time. The results are graphically presented and analyzed for various parameters. The study shows that the couple stress parameter and magnetic field significantly enhance the film pressure, load-carrying capacity, and squeeze film time compared to the Newtonian and nonmagnetic cases. Also from the results, it is observed that the squeeze film properties can be significantly reduced by the effect of the slip parameter. [ABSTRACT FROM AUTHOR]

The research on entropy generation in a mechanical system is quite imperative owing to its immense applications in the production of advanced cooling devices and medical appliances. The basic need on this research is how to optimize the irreversibilities within the systems and channelize that energy towards the benefit. This study elucidates the entropy generation analysis of a Casson nanofluid near a stagnation point over a lubricated vertical wall. A thin film of shear-thinning liquid with power law index of 0.5 is employed on the wall to ensure the lubrication. The effect of induced magnetic field and the chemical reaction stimulated by the activation energy is also incorporated within the flow. The non-linear PDEs of the substantive problem along with the compatible interfacial and boundary conditions are reverted into ODEs with the aid of suitable similarity transformation, and then cracked numerically using the sixth-order Runge Kutta method assisted with Nachtsheim–Swigert shooting practice. One of the significant findings reveals that the fluid friction irreversibilities in the entropy generation are diminished with the magnetic parameter and the Casson parameter, whereas the thermal irreversibility predominates over the total entropy generation for the escalating values of the activation energy parameter. [ABSTRACT FROM AUTHOR]

Chiral torsional anomalies have recently been applied in condensed matter and models of gravitation and quantum field theory, in particular in Dirac and Weyl materials. Moreover, Einstein–Cartan space–time elastic gauge spaces with vanishing spin connection have appeared in the teleparallelism framework. Recently, Ciappina et al. (PRD (2020)) have investigated torsion in quantum field theory through time loops on Dirac materials endowed with torsion in (2 + 1)-dimensional space–time where the third dimension is replaced by time dimension. They considered Riemann-flat spaces graphenes for example. In this paper, a space–time teleparallel geometry is used where we encoded physical information of Burgers vectors on Dirac curved materials (GdA, CQG 38 (2021)). It is shown that when the magnetic or pseudo-magnetic field is encoded in this metric one obtains an interesting (2 + 1)-dimensional space–time is shown to lead to pseudo-Maxwell equations. We also show that a Riemann-flat grapheno, for example, imposes a vanishing Nieh–Yan (NY) torsional anomaly, whereas a curved Dirac material presents a non-vanishing NY anomaly. Torsion-induced holonomy on Dirac materials is investigated. Signatures of chiral dynamo effects in Dirac materials from the chiral chemical potential encoded into the covariant derivative are found. It is shown that in the absence of chiral effect the magnetic field torsion contribution decays, whereas in the chiral dynamo case, a dynamo effect is found. It is shown that from the interaction of chiral chemical potential with torsion an effective chiral chemical potential is found, which depends on the zero-component of Cartan torsion. [ABSTRACT FROM AUTHOR]

This report describes a systematic approach for precise engineering of a catalyst‐metal oxide interface through combining complementary approaches of chemical vapor deposition and atomic layer deposition. Specifically, Chemical Vapor Deposition (CVD) fabricated nanostructured hard‐carbon framework (NCF) is employed as synergistic support for precise deposition of NiOx particles through Atomic Layer Deposition (ALD). The three variants of NCF‐NiOx system (dimensions ranging from 3–12 nm, surface coverage ranging from 0.14 %–2 %) achieved exhibit unique electrocatalytic water oxidation activities, that are further strongly influenced by an external magnetic field (Hext). This confluence of size engineering and associated magnetic field effects interplay to produce the largest lowering in Rct at Hext=200 mT. A comprehensive analysis of electrocatalytic parameters including the Tafel slope and double layer capacitance establishes further insights on co‐relation of size effect and magnetic properties to understand the role of nanocarbon supported transition metal oxides in water electrolysis. [ABSTRACT FROM AUTHOR]

This paper presents an asymptotic two-dimensional (2D) finite-deformation theory for a thin magnetoelastic sheet starting from a three-dimensional (3D) variational form. This theory is used to model wrinkling phenomena under applied traction and external magnetic field. The resulting 2D potential energy is specialized to an isotropic, in compressible material, and the expressions for material constants, i.e., elasticity tensor, magnetoelastic coupling constant, and permeability, are obtained as a function of the applied magnetic field. The formulation is further simplified assuming reflection symmetry about the mid-surface of the sheet. Strong form of the resulting 2D governing equations are obtained by setting the first variation of potential energy functional to zero. The resulting governing equations are used to analyze wrinkling in a stretched rectangular sheet placed in a uniform magnetic field. Approximate analytical solutions are obtained by linearizing the 2D plate equation for small slopes. The effect of magnetic field and applied stretch on onset of wrinkling and amplitude of wrinkles is studied. [ABSTRACT FROM AUTHOR]

Size-dependent effects in elastic deformation and thermal hysteresis effects in the heat transfer process are significant for small-size structures or devices. As an important component of micro- and nanoelectromechanical systems, the analysis of the thermodynamic properties of rotating nanobeams is crucial for the safe operation of the system. This work aims to construct a new nonlocal thermo-viscoelastic model and use this model to analyze the thermodynamic behavior of rotating nanobeams at the microscale. In this work, fractional order Kelvin-Voigt theory describes the viscoelasticity of materials. Moreover, the theory of continuous medium mechanics is improved by introducing nonlocal parameters to capture the size effect during deformation. Based on the generalized thermoelasticity theory, memory-dependent derivatives predict hysteresis effects during heat transfer. Nanobeams are placed in a longitudinal magnetic field. Graphene strips connected to a power supply are used as the nanobeam heat source. The effects of nonlocal parameters, damping coefficients, and fractional order parameters on the dynamic response of the system are analyzed. In addition, a new comparative study of the effects of voltage and resistance on the system is made in the context of the nonlocal generalized thermoelasticity theory. [ABSTRACT FROM AUTHOR]

The present article studies the two phase local/nonlocal deformation of magneto thermo electrical composite nano beam reinforced with graphene oxide powder (GOP). The controlling equation of motion and boundary conditions are derived via two phase elasticity in differential form conjunction with Hamilton's principle and Euler-Bernoulli beam model. The effect of a non-uniform magnetic and piezo electric field is incorporated with the governing equations by convoluting field quantities and displacement components. Then, Navier method is adopted to observe the influence of various boundary conditions on the dynamics of the beam. Comparison studies are performed to display the accuracy and efficiency of this analytical model. Further, the effects of magnetic field, GOP weight fraction, two phase parameter, external electric voltage, nonlocal parameter and temperature difference on the dimensionless frequency of GOP reinforced magneto piezo thermo elastic composite beams are thoroughly investigated and highlighted through tables and dispersion curves. [ABSTRACT FROM AUTHOR]

Numerous works have reported that magnetic fields serve as signals capable of influencing microbial metabolism. However, little is known about the effect of magnetic field on erythritol production by the model microorganism Yarrowia lipolytica (Y. lipolytica). Therefore, we investigated the effect of low-frequency alternating magnetic fields (LF-AMF) with different magnetic field intensities (0–1.5 mT) and different magnetic field treatment times (1–10 days) on the production of erythritol by Y. lipolytica -JZ204. The optimal treatment condition was 0.5 mT for 8 days. As a result, a maximal erythritol yield was achieved 63.74 g/L, the biomass was reached 37 g/L, and the specific erythritol yield per unit of biomass was 1.7227 g/g, which were 60.72%, 32.09%, and 24.85% higher than the control, respectively. We investigated the internal mechanism of magnetic fields impact by using transcriptomics and RT-qPCR technology. This study demonstrated the effectiveness of LF-AMF in enhancing erythritol production by Y. lipolytica JZ-204, providing insights for the application of magnetic field in assisting microbial fermentation and improving the synthesis of beneficial products. [ABSTRACT FROM AUTHOR]

Background: Very low‐field MR has emerged as a promising complementary device to high‐field MRI scanners, offering several advantages. One of the key benefits is that very low‐field scanners are generally more portable and affordable to purchase and maintain, making them an attractive option for medical facilities looking to reduce costs. Very low‐field MRI systems also have lower RF power deposition, making them safer and less likely to cause tissue heating or other safety concerns. They are also simpler to maintain, as they do not require cooling agents such as liquid helium. However, these portable MR scanners are impacted by temperature, lower magnetic field strength, and inhomogeneity, resulting in images with lower signal‐to‐noise ratio (SNR) and higher geometric distortions. It is essential to investigate and tabulate the variations in these parameters to establish bounds so that subsequent in vivo studies and deployment of these portable systems can be well informed. Purpose: The aim of this work is to investigate the repeatability of image quality metrics such as SNR and geometrical distortion at 0.05 T over 10 days and three sessions per day. Methods: We acquired repeatability data over 10 days with three sessions per day. The measurements included temperature, humidity, transmit frequency, off‐resonance maps, and 3D turbo spin echo (TSE) images of an in vitro phantom. This resulted in a protocol with 11 sequences. We also acquired a 3 T data set for reference. The image quality metrics included computing SNR and eccentricity (to assess geometrical distortion) to investigate the repeatability of 0.05 T image quality. The image reconstruction included drift correction, k‐space filtering, and off‐resonance correction. We computed the experimental parameters' coefficient of variation (CV) and the resulting image quality metrics to assess repeatability. We have explored the impact of electromagnetic interference (EMI) on image quality in very low‐field MRI. The investigation involved varying both the distance and amplitude of the EMI‐producing coil from the signal generator to analyze their effects on image quality. Results: The range of temperature measured during the study was within 1.5 °C. The off‐resonance maps acquired before and after the 3D TSE showed similar hotspots and were changed mainly by a global constant. The SNR measurements were highly repeatable across sessions and over the 10 days, quantified by a CV of 6.7%. The magnetic field inhomogeneity effects quantified by eccentricity showed a CV of 13.7%, but less than 5.1% in two of the three sessions over 10 days. The use of conjugate phase reconstruction mitigated geometrical distortion artifacts. Temperature and humidity did not significantly affect SNR or mean frequency drift within the ranges of these environmental factors investigated. The EMI experiment showed that as the amplitude increased the SNR decreased, and concurrently the root mean square of the background increased with a rise in EMI amplitude or a reduction in distance. Conclusions: We found that humidity and temperature in the range investigated did not impact SNR or frequency. Based on the CV values computed session‐wise and for the overall study, our findings indicate high repeatability for SNR and magnetic field homogeneity. [ABSTRACT FROM AUTHOR]

Magnetic fields, as a form of physical energy, exert an influence on biological activities. However, our current understanding of the impact of magnetic fields on wheat yield remains limited. In this study, our objective was to investigate the effects of magnetic field treatment of wheat plants on their yield, root growth, absorption of nitrogen and phosphorus and soil bacterial diversity. The experiments were conducted at two agricultural research stations in China, Zhengzhou and Xuchang. Plants were treated with magnetic fields of 20, 40, 60, and 80 mT induced by permanent magnets for chronic exposure. Untreated plants were considered as controls. Our result showed that soil nutrients were found to have a substantial impact on wheat nitrogen and phosphorus absorption, and wheat nitrogen and phosphorus absorption significantly affected wheat yield. The change in soil nutrient content was caused by the change in soil bacterial community diversity and abundance, and increased soil nutrients increased wheat yield. The results suggest that magnetic field treatment stimulated wheat plant growth and yield, and changed soil nutrient content through improved soil bacterial community diversity and increased soil nitrogen and phosphorous absorption. [ABSTRACT FROM AUTHOR]

This study developed a novel constructed wetland (CW) coupled with a magnetic field for treating domestic wastewater, and the magnetic field distribution was solved and optimised by the finite element method. Herein, we investigated the effects of optimising magnetic field optimisation and studied its impact on CW treatment performance and the responses of a microbial community. The optimisation results showed that the average magnetic field strength of the CW unit increases from 3 to 8 mT, and the proportion of areas with magnetic field strength greater than 5 mT also increases from 30% to 74%. The water quality analysis results showed that the removal of chemical oxygen demand (COD) and NH4+-N (p < 0.01) was significantly increased by the magnetic field (average 3 mT), increasing by 12.2% and 8.49%, respectively. Moreover, the removal of COD and NH4+-N (p < 0.01) was more significantly increased by M-VFCW(O) (average 8 mT), increasing by 15.58% and 49.1%, respectively. The magnetic field application shifted significantly the abundance of dominant bacteria in CWs. Relative abundance of dominant bacteria such as Proteobacteria (63.3%), Firmicutes (4.72%) and Actinobacteria (2.11%) that played an important role in organics removal and nitrification and denitrification-related bacteria such as Nitrospirae (1.48%) and Planctomycetes (9.58%) significantly promoted in M-VFCW(O). These results suggest that introducing a magnetic field into CWs may improve organics and nitrogen removal via the biological process, and the optimisation of the magnetic field was significant in enhancing the performance of VFCWs. [ABSTRACT FROM AUTHOR]

The principal parameter resonance of a ferromagnetic functionally graded (FG) cylindrical shell under the action of axial time-varying tension in magnetic and temperature fields is investigated. The temperature dependence of physical parameters for functionally graded materials (FGMs) is considered. Meanwhile, the tension bending coupling effect is eliminated by introducing the physical neutral surface. The kinetic and strain energies are gained with the Kirchhoff–Love shell theory. Based on the nonlinear magnetization characteristics of ferromagnetic materials, the electromagnetic force acting on the shell is calculated. The nonlinear vibration equations are obtained through Hamilton’s principle. Afterward, the vibration equations are discretized and solved by Galerkin and multiscale methods, respectively. The stability criterion for steady-state motion is established utilizing Lyapunov stability theory. After example analysis, the effects of magnetic field intensity, temperature and power law index on the static deflection are elucidated. Subsequently, the impacts of these parameters, as well as axial tension, on the amplitude-frequency characteristics, resonance amplitude, and multiple solution regions are discussed explicitly. Results indicate that the stiffness can be enhanced due to the generation of static deflection. The amplitude decreases with increasing magnetic field intensity, temperature, and power law index. When the magnetic field intensity surpasses a threshold, the resonance phenomenon disappears. [ABSTRACT FROM AUTHOR]

Research on the interfacial instability of two‐phase systems can help in gaining a better understanding of various hydrodynamic instabilities in nature. However, owing to the nonlinear and complex spatiotemporal dynamics of the unstable interface, the instability is challenging to control and suppress. This paper presents a novel interfacial instability of the magnetic microswarm induced by the competition between the destabilizing effect of magnetic field and the stabilizing effect of acoustic field. The physics underlying this novel phenomenon is discussed by analyzing the contributions of the external fields. Unlike previous studies, this study demonstrates that the instability is independent of the interfacial force or diffusion effect and can persist without dissipation over time. The manipulation of the unstable interface is further achieved by adjusting the configuration of the magneto‐acoustic system. This approach can be used in thermal encoding metamaterials and has great potential applications in systems where the instability is detrimental. [ABSTRACT FROM AUTHOR]

C45, a ferromagnetic material, can be strengthened by heat treatment such as quenching and is widely used as a material for general mechanical parts such as springs in automobiles. However, the presence of defects or flaws can cause cracking during the quenching stage, and a high-speed inspection method for detecting defects is required. In this study, we proposed and examined an inspection method for detecting defects using only a DC magnetic field by moving a round steel bar material at a high speed of 1 m/s inside a ring-shaped permanent magnet and generating eddy currents due to the velocity effect. [ABSTRACT FROM AUTHOR]

AbstractIn this work, a new method is proposed to utilize a magnetic filter material to suppress the escape of fugitive particles in the iron and steel industry. The magnetic filter material was prepared using the impregnation method, exhibiting superior demagnetization resistance. The magnetic field effect generated by magnetic filter material was combined with the diffusion, interception, and inertial effects of traditional filtration mechanisms to enhance the removal of fugitive particles. The magnetic polyimide filter material improves the filtration efficiency of particles with a diameter less than 2.0 μm by approximately 20% compared with polyimide filter materials. In addition, the filtration performance was further enhanced through electrostatic agglomeration. When the positive electrode voltage is +18 kV, and the negative electrode voltage is −16 kV, after the bipolar pre-charging treatment of fugitive particles with a diameter of 0.1–1.0 μm, the magnetic polyimide filter material can achieve a filtration efficiency of more than 90%, the magnetic polyimide (P84), magnetic polyphenylene sulfide (PPS), and magnetic fiberglass filter materials all achieve a filtration efficiency of over 94% with a diameter of 0.5–1.0 μm. This study lays the foundation for the proposal new dust removal methods for the iron and steel industry. [ABSTRACT FROM AUTHOR]

The introduction of external magnetic field has recently emerged as a great promising strategy for largely enhancing the efficiency of the electrocatalytic system, but it lacks a systematic understanding of the underlying mechanisms. This review is aimed at fully illuminating the recent research progress on magnetic field‐enhanced electrocatalysis via the combination of theoretical calculation and experiment results. The account begins by introducing basic systems employed for magnetic field generation, and then possible mechanisms for this magnetoelectric effect, including those associated with Lorentz and Kelvin forces, and magnetothermal, magnetohydrodynamic, spin selectivity, and Maxwell stress effects. Next, studies in which magnetic fields are utilized to enhance performances of a variety of electrocatalytic reactions are discussed in detail. Finally, a perspective of challenges and opportunities facing future research in this area is given. [ABSTRACT FROM AUTHOR]

Involvement of memristive term and additive physical variables including magnetic flux and charge can enhance the physical description of the biophysical neurons. Neural circuits coupled with memristors can be built and tamed to mimic the intrinsic biophysical characteristics and dynamical properties of biological neurons, and these memristive oscillator models are effective in predicting the mode transition in neural activities and self-organization in collective electric behaviors of neural networks. Any proposal of memristive map neurons requires reliable physical description. For example, the energy definition and self-adaptive working mechanism are crucial to verify the reliability of memristive maps. A capacitive variable is useful to describe the membrane potential, while the complexity of ion channels requires careful evaluation and description by using inductive variables relative to the electromagnetic field. In this work, a charge-controlled memristor is connected to an inductor in series for building a hybrid ion channel, and then a capacitor and a nonlinear resistor are combined to couple the ion channel. As a result, a simple memristive neural circuit is designed to discern the inner effect of electric field and magnetic field synchronously. The energy function is defined and verified with theoretical proof. Furthermore, a linear transformation is applied to convert this memristive neuron into a memristive map with an exact energy description, in which its dynamics and mode transition will be controlled by an adaptive law when its energy is beyond the threshold. Additive noise is imposed to induce coherence resonance, which can be detected by using the statistical analysis and average value for Hamilton energy function during changes in noise intensity. This scheme provides guidance for energy definition in memristive maps and the intrinsic energy regulation mechanism in neural activities is explained from physical and dynamical aspects. [ABSTRACT FROM AUTHOR]

Magnetic field-assisted method has been proved as an effective method to improve oxygen evolution reaction performance (OER) of water splitting, however, the essential reason for the improvement of OER performance still remains unclear. Herein, Ni 1- x Zn x Fe 2 O 4 ferrites were prepared by the combination of hydrothermal and calcination method, the magnetic properties, oxygen evolution reaction performance and the effect of applied magnetic field on OER performance were studied and discussed according to the magnetic properties and ion site situation. The magnetic field effect depended on the applied magnetic field strength and the magnetic magnetization density of catalysts, it was attributed to changes of electron state and redistribution of ions in the spinel structure. The overpotential decreased by approximately 50 mV and its double layer capacitance increased about 60 % at 125 mT applied magnetic field. The results provided a newness research view for the domain of electrochemistry. [ABSTRACT FROM AUTHOR]

Heavy‐metal‐free pure organic room temperature phosphorescence (ORTP) holds great potential in the field of organic optoelectronic devices owing to low economic cost, simple preparation techniques, and high exciton utilization. However, it is still filled with challenges in realizing high efficiency organic light‐emitting diodes (OLEDs) and exploring the internal physical mechanism based on these ORTP molecules. Here, a high‐performance OLED induced by an unexpected interfacial spin‐mixing process between the ORTP molecule and interlayers is demonstrated, and the high efficiency electroluminescence (EL) mechanism is studied through magneto–electroluminescence (MEL) and magneto–photoluminescence (MPL) measurements. The steady‐state and transient PL properties imply that the interfacial effect is related to a high‐lying singlet fission (HLSF) process in the ORTP molecule itself. Further, the HLSF process and the corresponding energy level position are confirmed by the incident wavelength‐ and temperature‐dependent PL spectra and the magnetic‐field‐dependent transient PL. Finally, by optimizing the interfacial material adjacent to the emissive layer to utilize this interfacial spin mixing effect, a high‐efficiency non‐doped ORTP‐OLED with external quantum efficiency of 16% and CIE coordinates of (0.27, 0.49) is developed. The proposed mechanism during the EL process will give insight to produce more efficient OLEDs based on ORTP materials in the future. [ABSTRACT FROM AUTHOR]

Key implementation points for achieving full accuracy in simultaneous temperature and magnetic field measurement and linearity when applying diamond quantum sensors to electric vehicle (EV) battery monitors were investigated. Both the static and busbar current magnetic field are required to be aligned to the NV-axis. If misalignment should exist, the resonance frequency midpoint move in the direction opposite to the temperature change under a large busbar current due to the transverse magnetic field effect. Misalignment could be quantified with an accuracy of ±1° by analysing the resonance frequency midpoint change under a current of ±1,000 A. The transverse magnetic field effects compensation estimated from misalignment, confirmed that the resonance frequency midpoint changed consistently with temperature changes. Furthermore, linearity over a wide dynamic range also improved. Moreover, it will contribute to accurate alignment of the two sensors for differential detection to eliminate external noise as common mode. These are expected to expand the application of diamond sensors for high-precision measurement in a wide dynamic range. [ABSTRACT FROM AUTHOR]

This study comprehensively investigates the effect of magnetic fields and thermal radiation on mixed convection in a hybrid alumina–copper/water nanofluid flowing over a permeable vertical flat plate. The study aims to model conventional nanofluid behavior accurately by considering the hybridization of two types of nanoparticles. Conventional similarity transformations and Akbari–Ganji's method are employed to simplify the governing equations, resulting in ordinary differential equations. Among the dual solutions obtained, only one stable solution is identified. The key findings reveal that boundary layer separation can be avoided by reducing the copper concentration volume and increasing the magnetic and radiation parameters. The mixed convection parameters induce counter-flow, enhancing heat transfer when the magnetic and radiation parameters increase and the copper concentration volume decreases. Conversely, increasing the concentration volume of copper leads to accelerated boundary layer separation and reduced measured physical quantities. Overall, the mixed convection parameter enhances skin friction and heat transfer rates, particularly in the achievable solution. The accuracy of the proposed method is validated through a comparison with the finite element method (FEM). The graphical presentation of the results facilitates a clearer interpretation of the study's findings. [ABSTRACT FROM AUTHOR]

The effect of external magnetic fields on the behavior of the Zhang-Rice exciton in NiPS3, which captures the physics of spin-orbital entanglement in 2D XY-type antiferromagnets, remains unclear. This study presents systematic study of angle-resolved and polarization-resolved magneto-optical photoluminescence spectra of NiPS3 in the Voigt geometry. We observed highly anisotropic, non-linear Zeeman splitting and polarization rotation of the Zhang-Rice exciton, which depends on the direction and intensity of the magnetic field and can be attributed to the spin-orbital coupling and field-induced spin reorientation. Furthermore, above the critical magnetic field, we detected additional splitting of the exciton peaks, indicating the coexistence of various orientations of Néel vector. This study characterizes orbital change of Zhang-Rice exciton and field-induced spin-reorientation phase transitions in a 2D hexagonal XY-type antiferromagnet, and it further demonstrates the continuous manipulation of the spin and polarization of the Zhang-Rice exciton. NiPS3 is a van der Waals antiferromagnet with a rich optical response including an exciton of very narrow linewidth, the origin of which is still a topic of active discussion. Herein, Song, Lv and coauthors study the response of the Zhang-Rice exciton to applied magnetic fields. [ABSTRACT FROM AUTHOR]

We present the results of direct measurements of the adiabatic temperature change (ΔTad) for the Fe50Rh50 alloy in a cyclic magnetic field (CMF) of 1.2 T. It is shown that increasing the frequency of the CMF from 1 to 30 Hz is accompanied by a shift of the position of temperature dependence ΔTad(T) maximum, Tmax, toward low temperatures. With an increase in the CMF frequency from 1 to 5 Hz, the ΔTmax value decreases by ∼12%. A further increase in frequency leads to stabilization of the effect. In the vicinity of the antiferromagnetic-ferromagnetic phase transition point TC = 370 K, ΔTad exhibits unconventional frequency behavior: while at T well above TC, the value of ΔTad monotonously decreases as frequency increases, at T = 370.4 K; an interval of frequency-independent ΔTad up to 10 Hz is observed, and at 368 K < T < TC, the maximum of ΔTad(f) dependence is found in the interval 1 < f < 10 Hz. Such behavior in the future can be applied in magnetic cooling technology due to large values of ΔTad and the frequency stability of the effect in alternating fields. The specific cooling power reaches giant values of ∼22 W/g at 20 Hz, which is comparable to the values under the same conditions for Gd −21.6 W/g. The unconventional behavior of ΔTad in the CMF is discussed in the context of the role of secondary phase localization, which leads to an enhanced internal local magnetic field and dynamic effects of ΔTad. [ABSTRACT FROM AUTHOR]

Magnetic field effects have received widespread attention due to their ability to enhance the process of water splitting at multiple scales. However, a systematic and comprehensive understanding of the source of the magnetic effect and the magnetic modulation of magnetic catalysts is lacking. This perspective focuses on recent advancements in harnessing external magnetic field to improve electrocatalytic water splitting and suggests future directions. First, the mechanism of several magnetic effects and their effects on water splitting are elaborated in detail, including the magnetohydrodynamic effect, magnetothermal effect, spin polarization effect, and magnetoresistance effect. Then, the classification and construction strategies of magnetic effect catalysts are summarized, primarily divided into single metal/alloy catalysts, metal oxide-based catalysts, and other magnetic catalysts. Finally, the challenges and potential perspective of magnetic field-enhanced water splitting are discussed, including mechanism study, in situ characterization, and multi-field synergy effects. [ABSTRACT FROM AUTHOR]

Planaria serve as an intriguing model system wherein the effects of electric and magnetic fields on various biochemical pathways during cell morphogenesis can be studied. Recent experimental observations have demonstrated the non-trivial modulation of reactive oxygen species (ROS) levels by a weak magnetic field (WMF) during planaria regeneration. However, the underlying biophysical mechanism behind this remains elusive. In this work, we investigate the role of the radical pair mechanism (RPM) and attempt to explain the experimental results of the effect of WMFs on ROS modulation during planaria regeneration. We also propose that instead of the flavin adenine dinucleotide-superoxide radical pair (FAD H • − O 2 • − ), a non-superoxide-based flavin adenine dinucleotide-tryptophan radical pair (F A D • − − Trp H • + ) might be a more suitable radical pair (RP) candidate for the observed ROS modulation. We also investigate the role of chirality-induced spin selectivity on ROS levels by including it in the framework of the RPM. We conclude that the singlet initiated F A D • − − Trp H • + is a more realistic choice of RP, and hence, superoxide formation might happen later and not during the RP spin dynamics. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of magnetic fields on health and disease have been subject to considerable research interest for the past few decades but still remain relatively poorly understood. Therefore, the identification of molecular and cellular pathways affected is of considerable importance. This study investigated the effects of very low magnetic field (LMF) exposure in a cellular model of prostate cancer (PCa), the second most common cancer diagnosed in men. Extracellular vesicles (EVs) are lipid structures released from and taken up by cells and play crucial roles in cell communication and in processes such as cancer spread via their protein and nucleic acid cargoes. Short-term (4 h) LMF exposure significantly altered the release profiles and protein content of EVs from PCa cells to a more pro-cancerous profile. We then investigated changes in several key micro-RNAs, which are regulators of cancer behaviour and indicators of cancer aggressiveness and metastasis. LMF exposure caused significant upregulation of three key oncogenic miRNAs (miR-155, miR-21, and miR-210) and significant downregulation of two key tumour-suppressive miRNAs (miR-126 and miR-200c) in the PCa cells. These changes were also associated with a significant increase in the cancer cells' invasion capability, which is a key indicator of cancer aggressiveness. We further verified the metastatic ability of the cancer cells caused by the LMF exposure by assessing two metastasis-related proteins, matrix metalloproteinases MMP2 and MMP9, which both were significantly increased. We compared these findings with normal prostate cells, which showed fewer changes in response to LMF exposure. Our findings suggest that LMF exposure may promote a more aggressive cancer phenotype by modulating key molecular and cellular pathways, highlighting the potential therapeutic implications of magnetic field modulation in cancer treatment. Prostate cancer is the second most common neoplasia and fifth-leading cause of cancer death in men worldwide. Electromagnetic and magnetic fields have been classified as possible human carcinogens, but current understanding of molecular and cellular pathways involved is very limited. Effects due to extremely low magnetic/hypomagnetic fields (LMF) are furthermore poorly understood. Extracellular vesicles (EVs) are crucial mediators of cellular communication with multifaceted roles in cancer progression, including via transport and uptake of various protein and microRNA (miRNA) EV-cargoes. miRNAs regulate gene expression and are implicated in cancer-related processes such as proliferation, metastasis, and chemoresistance. This study investigated the effects of LMF exposure (20 nT) by magnetic shielding on the prostate cancer cell line PC3 compared to the prostate epithelial cell line PNT2 under short-term (4 h) conditions. We examined EV profiles following a 4 h LMF exposure alongside associated functional enrichment KEGG and GO pathways for the EV proteomes. The 4 h LMF exposure significantly reduced cellular EV release and modified PC3 EV cargoes to a more inflammatory and metastatic profile, with 16 Disease Pathways and 95 Human Phenotypes associated specifically with the LMF-treated PC3 EV proteomes. These included cancerous, metabolic, blood, skin, cardiac and skeletal Disease Pathways, as well as pain and developmental disorders. In the normal PNT2 cells, less EV protein cargo was observed following LMF exposure compared with cells not exposed to LMF, and fewer associated functional enrichment pathways were identified. This pointed to some differences in various cellular functions, ageing, defence responses, oxidative stress, and disease phenotypes, including respiratory, digestive, immune, and developmental pathways. Furthermore, we analysed alterations in matrix metalloproteinases (MMPs) and miRNAs linked to metastasis, as this is crucial in cancer aggressiveness. The 4 h LMF exposure caused a significant increase in MMP2 and MMP9, as well as in onco-miRs miR-155, miR-210, miR-21, but a significant reduction in tumour-suppressor miRs (miR-200c and miR-126) in the metastatic PC3 cells, compared with normal PNT2 cells. In addition, 4 h LMF exposure significantly induced cellular invasion of PC3 cells. Overall, our findings suggest that changes in magnetic field exposures modulate EV-mediated and miR-regulatory processes in PCa metastasis, providing a basis for exploring novel therapeutic strategies. [ABSTRACT FROM AUTHOR]

Collisionless absorption of laser energy by an electron via laser–cluster interaction in an ambient magnetic field (B0) has recently renewed interest. Previously, using a rigid sphere model (RSM) and an extensive particle-in-cell (PIC) simulation with linearly polarized (LP) laser light, we have shown that an auxiliary field B0 in a transverse direction to the laser polarization significantly enhances the laser absorption [Swain et al., Sci. Rep. 12, 11256 (2022)]. In this LP case, the average energy ( E A ) of an electron rises nearly 30 − 70 times of its ponderomotive energy (Up). The two-stage laser absorption by cluster electrons has been attributed via anharmonic resonance (AHR) followed by electron-cyclotron resonance (ECR) satisfying the improved phase-matching and frequency-matching conditions simultaneously. In the present work, we study the effect of circularly polarized (CP) laser fields on the cluster-electron dynamics considering left/right circular polarizations with an ambient B0. In typical conditions, without B0, we show that both LP and CP light yield almost the same level of laser absorption (about 3 U p or less) by an electron. However, with B0, CP light enhances the electron's energy further by ≈ 10 − 20 U p beyond the previously reported values ≈ 30 − 70 U p by the LP light. These ejected electrons from cluster show narrow cone-like propagation as a weakly relativistic electron beam with an angular spread Δ θ < 5 ° and the beam quality improves in CP than LP. In all cases, RSM and PIC results show good agreement. [ABSTRACT FROM AUTHOR]

This study investigates the impact of the trailing effect on the accuracy of crack detection under high-speed conditions. Finite element simulation analysis was used to explore the effects of the trailing effect on the magnetic field distribution on the rail surface and compare the signal intensity and sensitivity at different detection positions. The optimal detection position with higher signal intensity and sensitivity was identified, and a probe structure suitable for electromagnetic non-destructive testing at high speeds was proposed. Experimental results show that at a detection speed of 20.0 m/s, this probe structure effectively quantifies cracks deeper than 1.0 mm, with relative errors and standard deviations within 10 %. [ABSTRACT FROM AUTHOR]

We consider a two-group social conflict under the corporates' research and development (R&D) business processes. Conflict participants are divided into two groups depending on their attitude to new ideas, technologies, and behavioral style for R&D creative problems—innovators and adapters. We reveal the contradiction that arises between the need to include both types of employees in one project team and their objectively antagonistic positions regarding the methods and approaches to R&D processes. The proposed research methodology is based on a modern post-non-classical paradigm formed on the principles of coherence, interdisciplinarity, openness, and nonlinearity, as well as a sociophysical approach to the social conflicts modeling. We use the general theories of magnetism, paramagnetism, and functions of P. Langevin and L. Brillouin to describe the dynamics of group participants' preferences regarding the style of conflict behavior. The analogy of paramagnetism, consisting in the orienting effect of the magnetic field, is used to describe social groups interactions that have not only their own interests, but are also influenced by the opinions of opposite social groups. A two-dimensional, four-parameter map represents the dynamics of group conflict. Modeling results show that regardless of the initial states and with certain parameters of intra-group and intergroup interactions, the trajectories eventually converge to an attractor (limit cycle) in a two-dimensional space. No non-periodic or chaotic modes are identified in the two-group conflict, which determines the controllability of the described conflict. The results of the simulation experiments are used as decision support and contradictions resolution aimed at forming the required modes of the corporates' research and development business processes and ensuring the group participants' cohesion and depolarization. The results of testing the model at an industrial enterprise are presented. [ABSTRACT FROM AUTHOR]

A performance evaluation system (PES) can experimentally test the structural stability and magnetic field effects of HTS coils against high magnetic fields and electromagnetic forces before mounting the HTS coils on a large-capacity rotating machine. This paper deals with the characteristic analysis of electromagnetic force in an HTS field coil for a 10 MW Class HTS Wind Power Generator using PES. Based on the designed 10 MW class HTS wind power generator, the HTS coils are manufactured and installed in the PES by a support structure, which is designed considering the electromagnetic force (torque) and heat loads in the HTS coil. To check the stress and deformation in the support structure caused by the electromagnetic force generated from the coil, strain gauge sensors were attached to the support structure and measured under full-load conditions. As a result, the maximum magnetic field and electromagnetic force are 2.8 T and 71 kN, respectively. Compared to the analysis results, the magnetic field and generated electromagnetic force in the HTS coil were the same under no-load and full-load conditions. These results will be effectively used to study and fabricate high magnetic field coils for HTS applications, as well as the PES being fabricated. [ABSTRACT FROM AUTHOR]

Effects of external magnetic field, microstructural effects and thermal effects on the dispersion and attenuation feature of elastic waves as well as the reflection and transmission behavior of coupled waves are studied in the paper. The microstructure effects are reflected by the dipolar gradient elasticity. The heat conduction behavior is modeled by non-Fourier law with the fractional order derivatives. The Lorentz force due to the external magnetic field is derived by the electromagnetic induction law and Maxwell equation. The numerical results are provided in the case of incident P wave. It is found that the microstructure effect induces the dispersive feature of elastic waves, while the dispersion and attenuation features are both induced by the thermal effects. The external magnetic field does not contribute to the dispersion but only influence on the amplitude of speed. The fractional order heat conduction only has evident influences on the propagation of thermal wave. [ABSTRACT FROM AUTHOR]

The conditions and influencing factors of hydrate formation is significant for hydrate technology. Combining with the existing literatures and the experimental data of this work, the phase equilibrium of CO2 hydrate in (NaCl/CaCl2/MgCl2) ionic solutions, pure water-sediment system and (NaCl/CaCl2/MgCl2) ionic solution-sediment systems under the static magnetic field (0.39 T) was studied. Moreover, the effect mechanism of magnetic field on hydrate phase equilibrium in different systems was analyzed in terms of intermolecular interaction. Under the same pressure, the magnetic field increased the phase equilibrium temperature of CO2 hydrate by 2.0–2.8 K in the three ionic solutions, which improved the hydrate formation conditions. This is mainly due to that the magnetic effect increases water activity and weakens the ionic hydration shells, thus promotes hydrate formation. In addition, compared with the ionic solution systems without magnetic field, the magnetic field increased the hydrate phase equilibrium temperature by 0.1–2.5 K in the ionic solution-sediment systems. However, the degree of temperature increase is less than that in the magnetic field-ionic solution systems, which is because the magnetic field enhances the binding between ions and the sediment particle in sediment-bearing systems. Compared with the magnetic field-ionic solution systems, the water activity in the magnetic field-ionic solution-sediment systems is lower, which makes hydrate formation more difficult. Moreover, with the movement of cations and anions in magnetic field, the crystals may be formed due to ion collisions, enhance the capillary action in ionic solution-sediment systems, and then hinder the hydrate formation. Therefore, the sediments can weaken the magnetic field promotion to hydrate formation. [ABSTRACT FROM AUTHOR]

• Exploring the influence of static magnetic field induction intensity on the freezing effect. • Static magnetic field shortens the maximum ice crystal formation region and the freezing process. • Static magnetic field has a delaying effect on the retrogradation of starch in fried rice. • Static magnetic field freezing further improved the quality of freezing-thaw fried rice. Magnetic fields are a new food-processing technology, with application in freezing, refrigeration, thawing, and preservation. In this work, the effects of static magnetic field (SMF) on freeze-thaw behavior, water distribution, retrogradation, and quality of fried rice are investigated. Results from the freezing curve show freezing time of fried rice during 2 mT treatment is the shortest, followed by 5 mT. Over a number of freeze-thaw cycles (FTC), the retrogradation enthalpy, relative crystallinity, and short-range ordered degree increased, while the application of the SMF can alleviate these processes. Changes in texture properties of samples treated by SMF are the significantly delayed in comparison with 0 mT, especially the adhesiveness index. The color and flavor of fried rice also show a delay downward trend. Therefore SMF can improve the quality of fried rice. The static magnetic field freezing method is appropriate for the actual production of frozen fried rice. [ABSTRACT FROM AUTHOR]

The present study aims to quantify the flow field, flow velocity, and heat transfer features over a horizontal flat plate under the influence of an applied magnetic field, with a particular emphasis on low Prandtl number fluids. Nonlinear partial differential expressions can be incorporated into the ordinary differential framework with the use of appropriate transformations. This research utilizes the variational iteration method (VIM) to approximate solutions for the system of nonlinear differential equations that define the problem. The objective is to demonstrate superior flexibility and broader application of the VIM in addressing heat transfer issues, compared to alternative approaches. The results obtained from the VIM are compared with numerical solutions, revealing a significant level of accuracy in the approximation. The numerical findings strongly suggest that the VIM is effective in providing precise numerical solutions for nonlinear differential equations. The analysis includes an examination of the flow field, velocity, and temperature distribution across various parameters. The study found that improving temperature patterns, velocity distribution, and flow dynamics were all positively impacted by increasing the Prandtl numbers. As a result, this leads to the thickness of the boundary layer to decrease and improves heat transfer at the moving surface. Thus, the convection process becomes more efficient. When the strength of the magnetic field is increased, the velocity of the fluid decreases. This observation aligns with expectations since the magnetic field hampers the natural flow of convection. Notably, the convection process can be precisely controlled by carefully applying magnetic force. [ABSTRACT FROM AUTHOR]

The current work is interested on investigating the impacts of thermal radiation, chemical reaction, and absorption radiation of a hydromagnetic convection‐free mass and heat transfer flow in case of an electrically conducting fluid that passes through a vertical plate moving impulsively. The analytical solutions of the governing momentum, energy, and species concentration equations with the initial and boundary conditions are obtained by the Laplace transformation technique. Graphs for fluid characteristics are used to analyze the impact of changing parametric quantities such as M, N, Sc, Kc, Q, Gr, Gm, and t on the temperature, velocity, concentration, and Sherwood number. We derive the engineering curiosity expressions for the Nusselt number and stress, and at the end, we tabulate and discuss the consequences of new parameters. The magnetic field effect and the chemical reaction are seen to diminish the fluid velocity and concentration, respectively, but in contrast, the absorption radiation effect is seen to accelerate both velocity and temperature. It is closely studied that the Nusselt number and skin friction values for hydrogen consistently exceed those for carbon monoxide. [ABSTRACT FROM AUTHOR]

In the current study, authors have studied the heat transfer through ternary hybrid nanofluid (THNF) between the gap of a disk and cone, where both are co-rotating with regard to the other. The authors have developed a mathematical model of THNF flow inside a gap between a cone and a disk with the effects of magnetic field, Hall effects, and radiation parameters. The unique aspect of this study is the implementation of a powerful artificial neural network (ANN) that exhibits improved robustness and accurate predictive performance for the Nusselt number at the surface of both the cone and disk. Through the use of proper similarity transformations, the model equations are transformed into a collection of nonlinear ODEs. Using MATLAB and an inbuilt bvp4c function, these equations are numerically solved. The main objective of this research is to examine the impacts of cone and disk rotation within the co-rotation system. The heat transfer rate is seen to be higher at the surface of the disk. It is followed from the analysis of the ANN model that the regression value for each case varies between 0.99574 and 1, and in many cases, it is exactly equal to 1. In addition, the mean square error (MSE) for every dataset is notably very close to zero. The effect of the angle of the conical gap is also one of the noteworthy subjects due to the significance of its effects in several engineering sector applications. [ABSTRACT FROM AUTHOR]

We investigate the emergence of magnetic skyrmion crystals with swirling topological spin textures in itinerant magnets with an emphasis on momentum-resolved multi-spin interactions. By performing the simulated annealing for the effective spin model with the two-spin and four-spin interactions on a two-dimensional triangular lattice, we show that various types of four-spin interactions become the microscopic origin of the magnetic skyrmion crystal with the skyrmion numbers of one and two. We find that the four-spin interactions between the different wave vectors lead to the skyrmion crystal with the skyrmion number of one, whereas those at the same wave vectors lead to the skyrmion crystals with the skyrmion number of one and two. Our results indicate that the multi-spin interactions arising from the itinerant nature of electrons provide rich topological spin textures in magnetic metals. [ABSTRACT FROM AUTHOR]