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To address the growing demand for a diverse range of shapes in optical components for evolving optical systems, this paper introduces a novel torus magnetorheological finishing (TMRF) method. This method harnesses the strengths of both magnetorheological finishing (MRF) and ring tools, thereby achieving ring tool with a guaranteed level of machining stability. Magnetic field analysis is performed in accordance with the Biot-Savart law, and the key excitation parameters are optimized, systematically designed, simulated, and experimentally validated. The design parameters comprise the pole width (w), pole gap (e), pole height (H), and the magnetic field's influence at the loop section (θmag), and the derived design specifications are sequentially w = 10 mm, e = 2 mm, H = 20 mm, θmag = 180°. The simulation of the magnetic field aligns closely with the theoretical calculations, mirroring the observed change trends from empirical magnetic field tests. For the TMRF under both short and long terms fixed-point polishing, the variations in material volume removal rate were ± 3.0% and ± 10.0%, respectively, and the variations in root mean square (RMS) values at the polishing tool's base were ± 3.8% and ± 2.0%, respectively. The experimental evidence confirms that TMRF exhibits a stable and highly effective polishing performance. Moreover, the design principles elucidated in this paper offer a significant reference for future research. [ABSTRACT FROM AUTHOR]

The detailed anisotropic dispersion of the low-temperature, low-energy magnetic excitations of the candidate spin-triplet superconductor UTe2 is revealed using inelastic neutron scattering. The magnetic excitations emerge from the Brillouin zone boundary at the high symmetry Y and T points and disperse along the crystallographic b ̂ -axis. In applied magnetic fields to at least μ0H = 11 T along the c ̂ − axis , the magnetism is found to be field-independent in the (hk0) plane. The scattering intensity is consistent with that expected from U3+/U4+ f-electron spins with preferential orientation along the crystallographic a ̂ -axis, and a fluctuating magnetic moment of μeff=1.7(5) μB. We propose interband spin excitons arising from f-electron hybridization as a possible origin of the magnetic excitations in UTe2. [ABSTRACT FROM AUTHOR]

We present a study on nanoscale skyrmionic spin textures in , a rare-earth complex noncollinear ferromagnet. We confirm, using X-ray microscopy, that can host lattices of metastable skyrmion bubbles at room temperature in the absence of a magnetic field, after applying a suitable field cooling protocol. The skyrmion bubbles are robust against temperature changes from room temperature to 330 K. Furthermore, the skyrmion bubbles can be distorted, deformed, and recovered by varying strength and orientation of the applied magnetic field. We have used nitrogen-vacancy nanoscale magnetic imaging to estimate and map the magnetic stray fields originating from our lamella samples and find stray field magnitudes on the order of a few mT near the sample surface. Micromagnetic simulations show an overall agreement with the observed behaviour of the sample under different magnetic field protocols. We also find that the presence of the Dzyaloshinskii-Moriya interaction is not required to reproduce our experimental results. Its inclusion in the simulation leads to a reversal of the skyrmionic object core polarity, which is not experimentally observed. Our results further corroborate the stability and robustness of the skyrmion bubbles formed in and their potential for future spintronic applications. [ABSTRACT FROM AUTHOR]

We present a study on nanoscale skyrmionic spin textures in , a rare-earth complex noncollinear ferromagnet. We confirm, using X-ray microscopy, that can host lattices of metastable skyrmion bubbles at room temperature in the absence of a magnetic field, after applying a suitable field cooling protocol. The skyrmion bubbles are robust against temperature changes from room temperature to 330 K. Furthermore, the skyrmion bubbles can be distorted, deformed, and recovered by varying strength and orientation of the applied magnetic field. We have used nitrogen-vacancy nanoscale magnetic imaging to estimate and map the magnetic stray fields originating from our lamella samples and find stray field magnitudes on the order of a few mT near the sample surface. Micromagnetic simulations show an overall agreement with the observed behaviour of the sample under different magnetic field protocols. We also find that the presence of the Dzyaloshinskii-Moriya interaction is not required to reproduce our experimental results. Its inclusion in the simulation leads to a reversal of the skyrmionic object core polarity, which is not experimentally observed. Our results further corroborate the stability and robustness of the skyrmion bubbles formed in and their potential for future spintronic applications. [ABSTRACT FROM AUTHOR]

High magnetic field-assisted solidification holds immense promise in manipulating the microstructures and properties of metallic materials. However, solute migration and redistribution at the solid-liquid interface during such solidification are not thoroughly understood at a microscopic level. To elucidate the mechanisms involved, directional solidification and quench experiments were performed with Cu–Ag eutectic alloys under various magnetic fields and solidification rates. The results showed that a high magnetic field intensified the solute enrichment of the liquid phase in front of the two eutectic phases simultaneously but to different extents. By calculating the solute partition coefficients, increased solute segregation can be confirmed under a high magnetic field. The changes in solute migration and redistribution behavior were attributed to the magnetic force and the Lorentz force, which can participate in a "cooperative" or "contrary" relationship depending on the magnetic susceptibility of the solute. This research helps clarify the solute redistribution behavior during eutectic alloy solidification under a high magnetic field, providing further theoretical basis for the modulation of alloy microstructures and properties by implementing high magnetic field-assisted solidification. [ABSTRACT FROM AUTHOR]

The emergence of nontrivial quantum states from competing interactions is a central issue in quantum magnetism. In particular, for the realization of the quantum spin-liquid state, extensive studies have been conducted on frustrated systems, such as kagome antiferromagnets and Kitaev magnets. Novel quantum states in magnetic fields have remained elusive despite the prediction of rich physics. This can be attributed to material scarcity and the difficulty of precise measurements under ultra-high magnetic fields. Here, in this study, we develop the Kapellasite-type compound InCu3(OH)6Cl3, whose exchange interactions are in appropriate energy scale to comprehensively elucidate the magnetic properties of the frustrated S = 1/2 kagome antiferromagnet. The one-third magnetization plateau was clearly observed. Moreover, the large temperature-linear term in the heat capacity was observed in the magnetic fields, indicating the excitation of gapless quasiparticles in the vicinity of the plateau. These results shed light on the critical behaviors between quantum spin-liquid and -solid in kagome antiferromagnets under high magnetic fields. A range of non-trivial quantum phenomena can emerge from frustrated magnetic systems and a prime example is a quantum spin liquid. Here, the authors conduct specific heat and magnetization measurements on the Kapellasite-type compound InCu3(OH)6Cl3 in order to characterize and define the range of the magnetization plateau in this material. [ABSTRACT FROM AUTHOR]

This work reports magnetic field direction dependent second magnetisation peak (SMP) anomaly in single crystals of oxygenated for ab. Detailed investigations on crystal A revealed the direction dependence of SMP anomaly at temperatures below 25 K, above which the direction dependence vanishes. The state of spatial order of the vortex lattice was found to be correlated to the vortex lattice symmetry that underwent a change at certain fields and was captured via single flux jumps observed in the third and fifth quadrant of magnetisation hysteresis loops. Bean's critical state profiles drawn to explain the flux jumps required the presence of clusters of in the basal plane of with closely lying binding energies. Large full width at half maximum observed in Cu, O, Y and Ba photoelectron spectra confirmed the validity of the proposed cluster model. A vortex phase diagram incorporating all features in the magnetisation hysteresis loops has been made for oxygenated for || ab depicting various phases. [ABSTRACT FROM AUTHOR]

Antiferromagnetic materials offer potential for spintronic applications due to their resilience to magnetic field perturbations and lack of stray fields. Achieving exchange bias in these materials is crucial for certain applications; however, discovering such materials remains challenging due to their compensated spin structure. The quest for antiferromagnetic materials with exchange bias became a reality through our experimental study and theoretical simulation on Sr 2 FeIrO 6 and Sr 2 CoIrO 6 . This study also unveils the impact of ionic disorder and lattice distortion on magnetic properties. The presence of exchange bias in both materials, given their antiferromagnetic nature, is intriguing. This study opens up new avenues for achieving exchange bias in spin-compensated systems, offering potential for low power and ultra fast antiferromagnetic spintronic applications in future research endeavors. [ABSTRACT FROM AUTHOR]

Spin-polarized lasers have demonstrated many superiorities over conventional lasers in both performance and functionalities. Hybrid organic-inorganic perovskites are emerging spintronic materials with great potential for advancing spin-polarized laser technology. However, the rapid carrier spin relaxation process in hybrid perovskites presents a major bottleneck for spin-polarized lasing. Here we report the identification and successful suppression of the spin relaxation mechanism in perovskites for the experimental realization of spin-polarized perovskite lasers. The electron-hole exchange interaction is identified as the decisive spin relaxation mechanism hindering the realization of spin-polarized lasing in perovskite microcrystals. An ion doping strategy is employed accordingly to introduce a new energy level in perovskites, which enables a long carrier spin lifetime by suppressing the electron-hole exchange interaction. As a result, spin-polarized lasing is achieved in the doped perovskite microcrystals. Moreover, the doped cation is a magnetic species allowing for the magnetic field control of the spin-polarized perovskite lasing. This work unlocks the potential of perovskites for spin-polarized lasers, providing guidance for the design of perovskites towards spintronic devices. Spin-polarized lasers have demonstrated many superiorities over conventional lasers. Here the authors report the identification and successful suppression of the spin relaxation mechanism in perovskites for the experimental realization of spin-polarized perovskite lasers. [ABSTRACT FROM AUTHOR]

The radical pair mechanism accounts for the magnetic field sensitivity of a large class of chemical reactions and is hypothesised to underpin numerous magnetosensitive traits in biology, including the avian compass. Traditionally, magnetic field sensitivity in this mechanism is attributed to radical pairs with weakly interacting, well-separated electrons; closely bound pairs were considered unresponsive to weak fields due to arrested spin dynamics. In this study, we challenge this view by examining the FAD-superoxide radical pair within cryptochrome, a protein hypothesised to function as a biological magnetosensor. Contrary to expectations, we find that this tightly bound radical pair can respond to Earth-strength magnetic fields, provided that the recombination reaction is strongly asymmetric—a scenario invoking the quantum Zeno effect. These findings present a plausible mechanism for weak magnetic field effects in biology, suggesting that even closely associated radical pairs, like those involving superoxide, may play a role in magnetic sensing. Magnetoreception is used for navigation by migratory animals. Here the authors use spin dynamics simulations to show how asymmetric recombination of radical pairs enables sensitivity in cryptochromes for Earth-strength magnetic fields. [ABSTRACT FROM AUTHOR]

Scanning magnetic microscopes enable high-sensitivity mapping of magnetic fields in thin geological sections, facilitating submillimeter- to submicrometer-scale studies of paleomagnetism and rock magnetism. Magnetic fields of geological samples have been mapped using various sensors, including Hall-effect devices, magneto-impedance devices, superconducting quantum interference devices (SQUIDs), quantum diamond devices, and tunnel magneto-resistance (TMR) devices. This study proposes magnetic microscopy using high-sensitivity room-temperature TMR sensors developed for biomagnetic applications. The goal was to create high-performance magnetic microscopes that do not require labor-intensive techniques, such as cryogenic technology. An XYZ stage developed for a scanning SQUID microscope (SSM) was used to demonstrate and evaluate magnetic microscopy with TMR sensors. The original TMR sensors developed for biomagnetic sensing composed of serially connected TMR elements with a total length of 2684 μm were shortened to 1073 μm (Sensor #1) and 357 μm length (Sensor #2). Background measurements at 50 Hz show magnetic field sensitivities better than 200 nT/√Hz and 600 nT/√Hz at 1 Hz for Sensor #1 and Sensor #2, respectively. By averaging 10 points of the original 50 Hz sampling, magnetic field sensitivities are better than 30 nT/√Hz and 90 nT/√Hz at 1 Hz for Sensor #1 and Sensor #2, respectively. To demonstrate TMR sensors as magnetic microscopes, a vertically magnetized Hawaii basalt thin section was measured and compared with a SQUID-acquired magnetic field map. Magnetic scanning images obtained with TMR sensors on a 0.1-mm grid were compared with those of SSM after adjusting the lift-off by upward continuation and integrated along the length of the sensors. The results demonstrated that magnetic images for 1073-μm-long (357 μm-long) TMR sensors aligned along the y-axis and x-axis are consistent with those after upward continuation to 0.3 mm (0.25 mm) and 0.4 mm (0.25 mm) and convolution by 1 × 10 (1 × 4) and 10 × 1 (4 × 1) matrix, respectively. Overall, the high-sensitivity TMR sensors exhibited promising performance. Further improvements can be made by optimizing the sensors, preamplifiers, and measurement systems for magnetic microscopy to achieve an optimum target resolution. [ABSTRACT FROM AUTHOR]

Controlling the magnetic domain propagation is the key to realize ultrafast, high-density domain wall-based memory and logic devices for next generation computing. Two-Dimensional (2D) Van der Waals materials introduce localized modifications to the interfacial magnetic order, which could enable efficient control over the propagation of magnetic domains. However, there is limited direct experimental evidence and understanding of the underlying mechanism, for 2D material mediated control of domain wall propagation. Here, using Lorentz-Transmission Electron Microscopy (L-TEM) along with the Modified Transport of Intensity equations (MTIE), we demonstrate controlled domain expansion with in-situ magnetic field in a ferromagnet (Permalloy, NiFe) interfacing with a 2D VdW material Graphene (Gr). The Gr/NiFe interface exhibits distinctive domain expansion rate with magnetic field selectively near the interface which is further analysed using micromagnetic simulations. Our findings are crucial for comprehending direct visualization of interface controlled magnetic domain expansion, offering insights for developing future domain wall-based technology. This study explores how the interface between Permalloy and graphene affects the propagation of magnetic domains. Using advanced transmission electron microscopy and simulations, the research reveals key insights that could advance future memory and logic technologies. [ABSTRACT FROM AUTHOR]

We consider the d-dimensional MagnetoHydroDynamics (MHD) system defined on a sufficiently smooth bounded domain, d = 2 , 3 with homogeneous boundary conditions, and subject to external sources assumed to cause instability. The initial conditions for both fluid and magnetic equations are taken of low regularity. We then seek to uniformly stabilize such MHD system in the vicinity of an unstable equilibrium pair, in the critical setting of correspondingly low regularity spaces, by means of explicitly constructed, static, feedback controls, which are localized on an arbitrarily small interior subdomain. In additional, they will be minimal in number. The resulting space of well-posedness and stabilization is a suitable product space B ~ q , p 2 - 2 / p (Ω) × B ~ q , p 2 - 2 / p (Ω) , 1 < p < 2 q 2 q - 1 , q > d , of tight Besov spaces for the fluid velocity component and the magnetic field component (each "close" to L 3 (Ω) for d = 3 ). Showing maximal L p -regularity up to T = ∞ for the feedback stabilized linear system is critical for the analysis of well-posedness and stabilization of the feedback nonlinear problem. [ABSTRACT FROM AUTHOR]

This paper investigates the ferrofluid flow within a square cavity considering the effects of viscosity. An elliptical obstacle with a high temperature is placed in the center of the cavity, and the vertical walls are cooled and covered with a conductive layer of varying thickness. Electrical current-carrying wires alongside the cooled walls generate the Kelvin force in the ferrofluid. Variables studied include the Ra and Ha, varying magnetic fields (MF), the thickness and thermal conductivity of the conductive wall, and the aspect ratio (AR). The equations are solved using the finite element method, and entropy (EnY) data and Nu are studied using the response surface method. Statistical analysis revealed that the AR significantly impacts the variations in the Ha and MNF. Results indicated that increasing the Ha decreases the generated EnY and the Nu m in the cavity, whereas increasing the strength of the varying MF increases both the generated EnY and the Nu m . An increase in the AR also leads to increased EnY production and Nu m . The maximum and minimum Nu were observed at conductive wall thicknesses of 0.05 and 0.1, respectively, with a difference of 88.6%. Increasing the wall thickness reduces thermal EnY by up to 91%, fluid EnY by 82.3%, and total EnY by 90.7% compared to their maximum values. Increasing the Ra from 1000 to 1,000,000 results in a 296, 2355, and 65.8% increase in the Nu m , fluid EnY, and total EnY, respectively, while reducing thermal EnY by 19.6% and Be by 88.8%. [ABSTRACT FROM AUTHOR]

Magnetic field effects (MFEs) in thermally activated delayed fluorescence (TADF) materials have been shown to influence the reverse intersystem crossing (RISC) and to impact on electroluminescence (EL) and conductivity. Here, we present a novel model combining Cole–Cole and Lorentzian functions to describe low and high magnetic field effects originating from hyperfine coupling, the g mechanism, and triplet processes. We applied this approach to organic light-emitting devices of third generation based on tris(4-carbazoyl-9-ylphenyl)amine (TCTA) and 2,2′,2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi), exhibiting blue emission, to unravel their loss mechanisms. The quality of the regression function was evaluated using k-fold cross-validation. The scoring was compared to various alternative fitting functions, which were previously proposed in literature. Density functional theory calculations, photoluminescence, and electroluminescence studies validated the formation of a TADF exciplex system. Furthermore, we propose successful encapsulation using a semi-permeable polymer, showing promising results for magnetic field sensing applications on arbitrary geometry. This study provides insights into the origin of magnetic field effects in exciplex-TADF materials, with potential applications in optoelectronic devices and sensing technologies. [ABSTRACT FROM AUTHOR]

Landau levels, previously proposed and verified in condensed matter systems, are conventionally achieved by introducing an external magnetic field that interacts with electrons. In phononic systems, people have proposed the method of applying strain to structures to form artificial synthetic magnetic fields, which in turn induces the emergence of Landau levels. While most of the current implementations about Landau levels are based on three-dimensional (3D) Weyl systems, the experimental realization of chiral Landau levels in two-dimensional (2D) Dirac acoustic systems remains an open and interesting topic. In this work, we present an innovative approach to generate the chiral Landau levels within a 2D acoustic system by introducing an in-plane artificial pseudomagnetic field. Through breaking the spatial parity symmetry and opening the Dirac cones, we introduce position-dependent effective mass terms to Hamiltonian and confirm the existence of chiral Landau levels by simulations and experiments. Furthermore, We verify the strong robustness of the zeroth Landau level to different kinds of defects. This work provides a feasible way to realize chiral Landau levels in 2D acoustic systems and suggests potential applications in other 2D artificial structures. [ABSTRACT FROM AUTHOR]

Topological superconductivity has attracted significant attention due to its potential applications in quantum computation, but its experimental realization remains challenging. Recently, monolayer Td−MoTe2 was observed to exhibit gate tunable superconductivity, and its in-plane upper critical field exceeds the Pauli limit. Here, we show that an in-plane magnetic field beyond the Pauli limit can drive the superconducting monolayer Td−MoTe2 into a topological superconductor. The topological superconductivity arises from the interplay between the in-plane Zeeman coupling and the unique Ising plus in-plane spin-orbit coupling (SOC) in the monolayer Td−MoTe2. The Ising plus in-plane SOC plays the essential role to enable the effective px + ipy pairing. As the essential Ising plus in-plane SOC in the monolayer Td−MoTe2 is generated by an in-plane polar field, our proposal demonstrates that applying an in-plane magnetic field to a gate tunable 2D superconductor with an in-plane polar axis is a feasible way to realize topological superconductivity. Topological superconductivity is the holy grail for implementing fault-tolerant quantum computation. Here, the authors show that for a superconducting monolayer Td−MoTe2 characterized by the Ising plus in-plane spin-orbit coupling, applying an in-plane magnetic field can drive it to a topological superconductor. [ABSTRACT FROM AUTHOR]

Topological superconductivity has attracted significant attention due to its potential applications in quantum computation, but its experimental realization remains challenging. Recently, monolayer Td−MoTe2 was observed to exhibit gate tunable superconductivity, and its in-plane upper critical field exceeds the Pauli limit. Here, we show that an in-plane magnetic field beyond the Pauli limit can drive the superconducting monolayer Td−MoTe2 into a topological superconductor. The topological superconductivity arises from the interplay between the in-plane Zeeman coupling and the unique Ising plus in-plane spin-orbit coupling (SOC) in the monolayer Td−MoTe2. The Ising plus in-plane SOC plays the essential role to enable the effective px + ipy pairing. As the essential Ising plus in-plane SOC in the monolayer Td−MoTe2 is generated by an in-plane polar field, our proposal demonstrates that applying an in-plane magnetic field to a gate tunable 2D superconductor with an in-plane polar axis is a feasible way to realize topological superconductivity. Topological superconductivity is the holy grail for implementing fault-tolerant quantum computation. Here, the authors show that for a superconducting monolayer Td−MoTe2 characterized by the Ising plus in-plane spin-orbit coupling, applying an in-plane magnetic field can drive it to a topological superconductor. [ABSTRACT FROM AUTHOR]

In the framework of the London model, computer modeling has been carried out and the distribution of the magnetic field in a massive superconductor of the II kind has been found, taking into account changes in the inhomogeneity of the magnetic field of an irregular vortex lattice. It is shown that the line shape changes significantly depending on the vortex lattice irregularity. This change should be taken into account when interpreting experimental data on the observation of the local magnetic field, the consideration of this circumstance can change the conclusions concerning the type of vortex lattice and the parameters of the superconductor. [ABSTRACT FROM AUTHOR]

Background: Effect of temperature fluctuations on the thermo-mechanical properties of engineering materials can be critical in many engineering applications. Moreover, electromagnetic fields also affect the stresses and their distribution in addition to thermo-elastic stresses in some engineering materials, leading to a complex coupling between different energy domains. Purpose: The proposed model enhances its ability to describe long-term interactions and memory effects by incorporating a non-singular kernel and non-local behavior. This suggestion is important because traditional thermoelasticity models often ignore non-local effects. Methods: Thermoelastic interactions in a thin, long, hollow tube immersed in a uniform electromagnetic field are considered. The Laplace transform method was applied to solve the governing equations in the transformed field, and the Dubner and Abate technique was applied to calculate the numerical results for the system fields. Results: The results presented in the graphs were discussed, analyzed, and compared with the results of the corresponding traditional and generalized thermoelastic models, and the effect of operating factors and fractional order was studied. Conclusion: Changing the fractional derivative order improves memory and heredity. This slows changes in electric and magnetic fields and emphasizes dispersion. [ABSTRACT FROM AUTHOR]

Purpose: The vibration characteristics of an isotropic and homogeneous elastic hollow cylinder with double porosity, emphasizing the influence of the magnetic field in the context of nonlocal elasticity, are investigated. The constitutive relations and governing equations are described in the radial direction. Methods: A technique of time-harmonic vibration is implemented to derive a set of ordinary differential equations from the governing equations. The frequency equation for the vibration continuation is established under the conditions of traction-free boundary conditions. MATLAB software is employed with a numerical iteration method to explore free vibration analysis. Results: Analytical results have been authenticated with Computer-simulated numerical results and are presented through graphical representations illustrating the frequency shift for both the nonlocal and local elastic cylinders with double porous structures under the influence of a magnetic field. Conclusion: Numerically simulated data are tabulated to depict natural frequencies as a function of the mode numbers. The distinct behaviors associated with specific modes and the tendency towards linearity as the mode numbers increase highlight the intricate interaction between the magnetic field and the dynamic attributes of the system. [ABSTRACT FROM AUTHOR]

In this study, it is shown that in the Kraenkel–Manna–Merle system (KMMS) an internal magnetic field (IMF) can be generated. This is achieved mathematically as the equation that describes the external magnetic field is integrable. An evolutionary system can generate an internal source by introducing the "duality transformation" which leads to creating "dual waves". Alongside a non-autonomous KMMS is considered, that describes nonuniform magnetic field formation. The system's exact solutions are found using the extended unified method. Various wave patterns are revealed, fission-fusion graded solitons, braided solitons, envelope solitons, zig-zag cliff wave shape, lump vector, zig-zag cavity solitons. and upper and lower saucers with surface-based lattices. The most revealed interesting phenomenon is the localization of the magnetic field created in FMMs, which agrees with the experimental work. The sensitivity of the system is tested against the IMF and also, against a perturbation in the external magnetic field. It is remarked that the intensity of the magnetic field, created in ferromagnetic materials, is highly exceeding that one of the external magnetic field amplitude. That is, magnetization by time varying magnetic field is highly efficient. [ABSTRACT FROM AUTHOR]

Quantum dense coding enables the transmission of two bits of classical information using a single qubit, leveraging the initial maximal entanglement of a Bell state channel. This study investigates this process within a two-qubit anisotropic XY Heisenberg spin chain, influenced by Herring-Flicker coupling and subjected to an external magnetic field. In practical scenarios, the interaction between spins, characterized by the variable coupling strength J, significantly impacts the assessment of these spin systems for quantum computing and communication. Therefore, it is essential to consider the distance between the spins. This article aims to analyze the effects of temperature variations on the quantum communication channel, taking into account Herring-Flicker coupling, which is vital for implementing quantum communication protocols in real-world applications. Our findings suggest that the current channel shows promising potential for the quantum-dense coding protocol. [ABSTRACT FROM AUTHOR]

In this paper, a three dimensional multi-load wireless power transfer (WPT) system is designed and optimized for the sensor network which has the characteristics of large number, low power consumption, and wide spatial distribution. Firstly, a new structure of three-dimensional multi-load WPT system is proposed and its circuit model is established, and the influencing factors of transmission efficiency and power are analyzed. Then, the magnetic coupling structure is specifically designed, and a toroidal spiral coil structure is proposed, which is used as repeating coil and several receiving coils nested to form the receiving side. The magnetic field simulation of the new coil structure is analyzed by Ansys. The 3D WPT system prototype can transmit power up to 2 W at a transmission distance of 20 cm. When the receiving side is connected to a single load, the maximum transmission efficiency is 44%, and the fluctuation of transmission efficiency with revolution is reduced by changing the current phase, and the energy transmission blind area is eliminated. When the receiving side is connected to multiple loads, the output power of each load reaches 2 W at 92% test points in the spherical space of the transmitting side, which meets the power consumption requirements of the sensor equipment. [ABSTRACT FROM AUTHOR]

The article is devoted to theoretical studying the dynamic response of ensembles of nanosized ferromagnetic particles immobilized in a nonmagnetic medium to an external field. The main attention of the work is paid to analyzing the effect of interparticle magnetic interactions on the complex magnetic susceptibility of a composite and the intensity of heat generation in it under the action of the alternating magnetic field. The analysis has shown that the dependence of the magnitude of the thermal effect on the parameter of the interparticle magnetodipole interaction is nonmonotonic and passes through a maximum. We hope that this result will help to understand the physical reason for the qualitative contradictions between the conclusions inferred in different studies devoted to the influence of the interparticle interactions on the components of the complex magnetic susceptibility of magnetic composites and the intensity of the heat generation under the action of alternating fields. [ABSTRACT FROM AUTHOR]

The determination of the amount and composition of artificial polymer microparticles in ponds requires the preparation of representative water samples. A new method has been proposed in this work for magnetic separation of polyethylene microparticles (PEMPs, 10–200 μm), with the method implying their aggregation with magnetic nanoparticles. Composite magnetic nanoparticles containing magnetite cores and silica shells functionalized with amino groups (Fe3O4@SiO2–NH2, dhydr = 200 nm) have been synthesized and characterized. Due to electrostatic interactions, these nanoparticles can form aggregates with polyethylene particles and be separated from water under the action of a gradient magnetic field. The effects of added salts (NaCl, Na2SO4, NaH2PO4, and CaCl2) and a surfactant, sodium dodecyl sulfate (SDS), on the separation conditions of PEMPs from water have been studied. It has been shown that the addition of the magnetic particles in concentration c = 0.01 g/L to aqueous suspensions containing NaCl and NaH2PO4 (c = 10 mM), and SDS (c = 3 mM) provides an efficiency of magnetic separation of PEMPs equal to, at least, 98% after preliminary exposure for 30 min and magnetic sedimentation for 15 min. As the concentration of NaCl and NaH2PO4 is increased to 100 mM or in the presence of Na2SO4, the efficiency of PEMP magnetic separation decreases. In the presence of CaCl2 and SDS, the efficiency of the magnetic sedimentation is no less than 98% at the studied concentrations of the salts. At least 80% of PEMPs are separated by magnetic filtration from model solutions simulating river and sea water within 5 min. [ABSTRACT FROM AUTHOR]

The paper presents the results of computer simulating the structure formation in nanodisperse magnetic fluids and the influence of this process on the kinetics of their magnetization reversal. The work considers a system of identical spherical single-domain ferromagnetic particles suspended in a Newtonian fluid with magnetic moments "frozen" into the particle bodies. The particles are involved in intense Brownian motion. The magnetic interactions of all particles with each other, as well as of the particles with an external magnetic field, are considered. The results have shown that the evolution of the internal structures upon a change in the external field can greatly, by several orders of magnitude, change the characteristic time of ferrofluid magnetization reversal. The results obtained may be useful for the development of both the general theory of these systems and many methods for their high-tech applications. [ABSTRACT FROM AUTHOR]

Based on observations conducted at the Ernest Gurtovenko Horizontal Solar Telescope, the height of the polar chromosphere of the Sun was determined for the period 2012–2023. The measurement was calculated as the difference between the positions of the maximum radial brightness gradients in the continuum and at the core of the Hα line. The results indicate that the height of the polar chromosphere is lower near the maximum of the solar cycle (approximately 4500 km, or 6.3″) and higher near the minimum of the cycle (approximately 5000 km, or 6.9″). The chromosphere's height at the southern pole in 2012–2013 and, particularly, 2016–2017 was higher than at the northern pole. This north–south asymmetry is likely related to differences in the dynamics and magnitude of the polar magnetic fields during Solar Cycle 24. The findings demonstrate that the time changes in the chromosphere's height closely correlate with sunspot numbers, the strength of the polar magnetic field, and chromospheric indices of solar activity. The correlation coefficient between the average annual height of the chromosphere and the smoothed relative sunspot number is –0.64 for the northern hemisphere and –0.75 for the southern hemisphere. The correlation coefficient between the average annual height of the chromosphere and the smoothed values of the polar magnetic field strength (based on data from the Wilcox Solar Observatory) is 0.86 for the northern hemisphere and 0.53 for the southern hemisphere (the latter value increases to 0.77). The correlation coefficient between the average annual height of the chromosphere and the chromospheric index IK2 reaches the highest values, 0.91, for the northern pole and 0.80 for the southern pole. [ABSTRACT FROM AUTHOR]

Direct magnetic field measurements in sunspots by many spectral lines are important for elucidating the true magnitude and structure of the magnetic field at different levels of the solar atmosphere. Currently, magnetographic measurements are the most widespread, but such measurements mainly represent the longitudinal component of the magnetic field. In the sunspot umbra, such measurements give unreliable information and do not allow for determining the actual value of the module (absolute value) of the magnetic field. Such data can be obtained from spectral-polarization observations, thanks to which the magnetic field can be determined directly from Zeeman splitting, rather than as calibrated polarization in line profiles. The presented work presents the results of the study into the magnetic field in the sunspot on July 17, 2023, which was observed on the Echelle spectrograph of the horizontal solar telescope of the Astronomical Observatory of Taras Shevchenko National University of Kyiv. The I ± V profiles of ten photospheric lines of Fe I, Fe II, Ti I, and Ti II were analyzed in detail. The strongest magnetic field measured by the Fe I lines reaches 2600 G, and the difference in the measured intensities by these lines is sometimes at the level of 50–80%. The umbral lines of Ti I show, in general, the same magnetic fields as Fe I lines, while the lines of Fe II and Ti II show significantly weaker fields. Although the lateral field profile in the spot by most of the Fe I lines is smooth, quasi-Gaussian, one of the lines, namely Fe I λ 629.10 nm, shows a "dip" at 400–600 G in the sunspot umbra, which, most likely, is real. The obtained data probably indicate a combination of at least two effects: the dependence of measurements on the height of line formation in the solar atmosphere and the manifestation of Zeeman "saturation" in lines with different Lande factors. It also turned out that the umbral line of Ti I λ 630.38 nm shows somewhat stronger magnetic fields compared to non-umbral lines. The obtained data are planned to be used to clarify the general picture of the magnetic field in the spot by means of simulation. [ABSTRACT FROM AUTHOR]

Magnetorheological (MR) fluids are utilized to develop a variety of electromechanical devices that have potential applications in the automotive, medical, aerospace, and other areas. Since yield stress is the most important design parameter of an MR fluid and its devices, it is dependent on the types of operational modes. This paper thoroughly examines the effects of the operational modes of MR fluids such as shear mode, and squeeze mode along with the impact of mixed-mode operation on the performance of MR fluids and devices. The study found that mixed-mode operation results in higher yield stress and offers better performance control for MR fluid devices compared to single-mode operation under the same working conditions. Several factors impact the performance of MR fluid devices in various operational modes discussed in the paper such as geometry, initial gap thickness, temperature, pressure, velocity, applied compressive strain, response time, magnetic particle composition, magnetic field, and other working factors. Therefore, there is a necessity to thoroughly examine the rheological and mechanical behaviors of MR fluids and the performance of MR devices in different operational modes and working circumstances, highlighting the experimental and theoretical findings conducted by researchers. [ABSTRACT FROM AUTHOR]

Wave trains of magnetic field and ion-flux oscillations generated upstream of the ramp of interplanetary (IP) shock were studied according to BMSW plasma-spectrometer measurements of energy–time spectra of the solar-wind ions supplemented by magnetic-field measurements. It was shown that oscillations of the magnetic field upstream of the ramp of IP shock are accompanied by oscillations of the ion flux. A detailed analysis of two cases is carried out, and the results of statistical study are presented. Right-handed circular or elliptical polarization was observed in all wave trains of magnetic-field oscillations, which is consistent with the characteristics of magnetosonic oscillations corresponding to the low-frequency branch of whistler waves. It was obtained that the mean angles between the propagation direction of whistler waves relative to the magnetic field and shock normal direction were 31° and 40°, respectively. This result suggests that the wave packets upstream of the ramp of IP shock had the properties of propagating whistler waves. It was found that, on average, with an increase in the angle of propagation of whistler waved relative to the shock normal direction θkn, the angle between the wave vector and magnetic-field direction θkB decreases. [ABSTRACT FROM AUTHOR]

MMS four-spacecraft observations with high temporal and spatial resolution made it possible to study the characteristics of intense superthin current sheets (SCSs) with a current density J > 30 nA/m2, formed in bursty bulk flows (BBFs), propagating in the Plasma Sheet (PS) of the magnetotail from the remote X line. Statistical analysis of >1000 SCSs observations showed that, in the majority of cases, the current in the SCSs is parallel to the ambient magnetic field and is carried by field-aligned accelerated electron beams. The half-thickness of the SCSs is several electron gyroradii, and in such thin layers the electric current is carried by demagnetized electrons. Bursts of strong nonideal electric fields E' > 10 mV/m are often observed at the edges and/or inside the SCSs. The generation of such fields brings about energy conversion in the SCSs of hundreds of pW/m3, and in some cases up to several nW/m3, which is comparable to the energy conversion in the electron diffusion region of magnetic reconnection. The strongest energy release is observed in the SCSs formed in the fastest BBFs and under strong variations of the magnetic field in the tail lobes. [ABSTRACT FROM AUTHOR]

This article investigates the dynamic features of domain walls in a bilayer piezoelectric-magnetostrictive heterostructure under the influence of piezo-induced strains, inertial damping, and dry friction dissipation. We assume that the magnetostrictive material belongs to the transversely isotropic hexagonal crystal. The analysis is carried out within the framework of the inertial Landau-Lifshitz-Gilbert equation, which describes the ultrafast evolution of magnetization inside the magnetostrictive materials. By employing the classical traveling wave ansatz, the study explores how various factors such as magnetoelasticity, dry friction, inertial damping, crystal symmetry, and a tunable external magnetic field characterize the motion of the magnetic domain walls in both steady-state and precessional dynamic regimes. The results present valuable insights into how these key parameters can effectively modulate dynamic features such as domain wall width, threshold, Walker breakdown, and domain wall velocity. The obtained analytical results are further numerically illustrated, and a qualitative comparison with recent observations is also presented. [ABSTRACT FROM AUTHOR]

Solar eruptions, primarily manifested as solar flares, filament eruptions and coronal mass ejections, represent explosive releases of magnetic energy stored in the solar corona, with the potential to drive severe space weather. The initiation of solar eruptions remains an open question, leading to various theoretical models that are inferred from observations. However, these models are subjects of debate due to the absence of direct measurements of the three-dimensional (3D) magnetic fields in the corona. Numerical simulations, based on solving magnetohydrodynamics (MHD) equations that govern the macroscopic dynamics of solar corona, serve as a touchstone for testing these theoretical models. One early proposed model suggested that eruptions could be triggered by reconnection within a single sheared magnetic arcade, which is known as the tether-cutting reconnection model, but it was never confirmed through 3D MHD simulations until very recently. Consequently, two models have gained more popularity: one involving the eruption of a twisted magnetic flux rope (MFR) due to ideal instability (or loss of equilibrium), and the other known as the breakout eruption, which requires a quadrupolar configuration with a delicately located magnetic null point. Other mixed mechanisms, involving both ideal instability and reconnection, are also proposed in association with localized magnetic flux emergence. Now with the validation of the tether-cutting model, the fundamental mechanisms are boiled down to two types of models, one primarily based on the ideal instability of a pre-existing MFR, and the other based on the reconnection of sheared field lines with or without an MFR. Recently, the modelling of the birth of solar eruption using observed data-based MHD simulations has advanced rapidly, becoming a crucial research tool in the study of the initiation mechanisms. These realistic modellings reveal a higher level of complexity compared to all currently available theories and idealized models. [ABSTRACT FROM AUTHOR]

This paper concerns the free-surface problem of incompressible ideal MHD fluids with velocity damping in a two-dimensional (2D) horizontally periodic slab domain impressed by a uniform horizontal magnetic field. We prove that the problem is globally well-posed for the small initial data and the solution decays exponentially in time to the equilibrium, where both the Taylor sign condition and the surface tension are not required in this paper due to the stabilizing effect of horizontal magnetic field. [ABSTRACT FROM AUTHOR]

Multi-dimensional wireless power transmission is a critical element in the development of capsule robots. To solve the problem caused by the increasing number of functions of new capsule robots and the fact that the traditional three-dimensional receiving coil occupies excessive inner space, a two-dimensional square transmitting coil with an embedded ferrite core is proposed. The proposed transmitting coil consists of two pairs of rectangular solenoid coils distributed radially along the human body. By changing the direction of the current flow, it can generate a two-dimensional magnetic field covering the whole central plane. This paper presents a theoretical model and conducts finite element simulations to analyze the magnetic flux density in the center plane. To evaluate the effectiveness of the proposed system, two prototypes of transmitting coils with and without ferrite cores are created, tested and compared to assess the performance improvements. Results indicate that the transmitting coil with a ferrite core increases the power transfer efficiency from 5.07% to 6.11%. In addition, attitude experiments reveal that the receiving coil efficiently captures sufficient energy at various angles when operated in the center plane. [ABSTRACT FROM AUTHOR]

We consider a free boundary problem for the two-dimensional plasma-vacuum interface ideal magnetohydrodynamic (MHD) flows. In the plasma region, the flow is governed by the compressible ideal MHD equations, while in the vacuum region, we consider the full-Maxwell equations for the electric and the magnetic fields. At the free interface, driven by the plasma velocity, the total pressure is continuous and the magnetic field on both sides is tangent to the boundary. We establish a linear stability/instability criterion of equilibrium state for the Rayleigh-Taylor (RT) problem and the linear stability for the ideal MHD equations. More specifically, we study the stabilizing effect of impressed magnetic fields upon solutions to the equations obtained by linearization around the equilibrium state. We give the critical magnetic number H c by a modified variational method and prove that the linearized system is stable when the horizontal impressed magnetic field H ¯ = ( H ¯ 1 , 0) satisfies | H ¯ 1 | > H c , while unstable for | H ¯ 1 | < H c . [ABSTRACT FROM AUTHOR]

In this paper, we revisit the Cauchy problem for the three dimensional nonlinear Schrödinger equation with a constant magnetic field. We first establish sufficient conditions that ensure the existence of global in time and finite time blow-up solutions. In particular, we derive sharp thresholds for global existence versus blow-up for the equation with mass-critical and mass-supercritical nonlinearities. We next prove the existence and orbital stability of normalized standing waves which extend the previous known results to the mass-critical and mass-supercritical cases. To show the existence of normalized solitary waves, we present a new approach that avoids the celebrated concentration-compactness principle. Finally, we study the existence and strong instability of ground state standing waves which greatly improve the previous literature. [ABSTRACT FROM AUTHOR]

A numerical study is performed to examine the influence of a non-uniform magnetic field on the thermo-hydraulic behaviour of a ferrofluid. The analysis is done in the context of a differentially heated semi-circular annulus where a magnetic dipole with its distinct location and dipole strength is used to obtain different configurations. The field variables are computed by solving the coupled set of flow equations, energy equations and the Maxwell's magneto-statics equations. A detailed description is provided on the flow and thermal response after observing different parameters at both global and local scale. Comparison of streamlines and isotherms with a reference case of natural convection concludes that the recirculation zones are responsible for the increased velocity and heat transfer magnitudes. Another key finding of the present work is about the possibility to locally improve the thermal performance of heat exchangers at any desired position along the circumference. [ABSTRACT FROM AUTHOR]

We describe a compact calorimeter that opens ultra-low-temperature heat capacity studies of small metal crystals in moderate magnetic fields. The performance is demonstrated on the canonical heavy fermion metal YbRh 2 Si 2 . Thermometry is provided by a fast current sensing noise thermometer. This single thermometer enables us to cover a wide temperature range of interest from 175 µK to 90 mK with temperature-independent relative precision. Temperatures are tied to the international temperature scale with a single-point calibration. A superconducting solenoid surrounding the cell provides the sample field for tuning its properties and operates a superconducting heat switch. Both adiabatic and relaxation calorimetry techniques, as well as magnetic field sweeps, are employed. The design of the calorimeter results in an addendum heat capacity which is negligible for the study reported. The keys to sample and thermometer thermalisation are the lack of dissipation in the temperature measurement and the steps taken to reduce the parasitic heat leak into the cell to the tens of fW level. [ABSTRACT FROM AUTHOR]

We consider the classical vacua of the Weinberg–Salam (WS) model of electroweak forces. These are no-particle, static solutions to the WS equations minimizing the WS energy locally. We study the WS vacuum solutions exhibiting a non-vanishing average magnetic field of strength b and prove that (i) there is a magnetic field threshold b ∗ such that for b < b ∗ , the vacua are translationally invariant (and the magnetic field is constant), while, for b > b ∗ , they are not, (ii) for b > b ∗ , there are non-translationally invariant solutions with lower energy per unit volume and with the discrete translational symmetry of a 2D lattice in the plane transversal to b, and (iii) the lattice minimizing the energy per unit volume approaches the hexagonal one as the magnetic field strength approaches the threshold b ∗ . In the absence of particles, the Weinberg–Salam model reduces to the Yang–Mills–Higgs (YMH) equations for the gauge group U(2). Thus, our results can be rephrased as the corresponding statements about the U(2)-YMH equations. [ABSTRACT FROM AUTHOR]

The problem of a hydrogen atom in a strong magnetic field is a notorious example of a quantum system that has genuinely different asymptotic behaviors in different directions. In the direction perpendicular to the magnetic field the motion is quadratically confined, while in the direction along the field line the motion is a Coulomb-distorted free motion. In this work, we identify the asymptotically relevant parts of the Hamiltonian and cast the problem into a Lippmann-Schwinger form. Then, we approximate the asymptotically irrelevant parts by a discrete Hilbert space basis that allows an exact analytic evaluation of the relevant Green's operators by continued fractions. The total asymptotic Green's operator is calculated by a complex contour integral of subsystem Green's operators. We present a sample of numerical results for a wide range of magnetic field strengths. [ABSTRACT FROM AUTHOR]

This research investigates the complex statistical behavior of fermion-antifermion pairs within a (2+1)-dimensional magnetized Bonnor-Melvin background affected by non-zero cosmological conditions. The Bonnor-Melvin magnetic universe model, known for its cylindrical symmetry, preserves the invariance of quantum field dynamics under Lorentz boosts along the z -axis. This framework facilitates the examination of (2+1)-dimensional scenarios, where the corresponding spacetime background is identified as the Bonnor-Melvin magnetic 2+1+0-brane solution within the realm of gravity coupled with nonlinear electrodynamics. Initially, the precise energy spectra of these pairs are summarized using an analytical solution derived from the fully covariant two-body Dirac equation. Subsequently, the statistical properties inherent in these pair formations are investigated. These findings may illuminate the interplay among magnetic fields, spacetime geometry, and the cosmological constant, thereby enhancing our comprehension of the fundamental behaviors of fermions amidst intricate cosmological conditions. It is anticipated that this investigation could offer new insights into the statistical attributes of fermion-antifermion systems. All thermal characteristics, including free energy, total energy, entropy, and specific heat, have been computed. The impact of diverse factors, such as magnetic fields, spacetime geometry, and the cosmological constant, on these characteristics has been scrutinized. [ABSTRACT FROM AUTHOR]

We present a simple model of composite particle tunnelling through a potential barrier in presence of a (pseudo)magnetic field. The exact numerical solution of the problem is provided and the applicability to real physical systems is discussed. When the magnetic field is present some new qualitative features of the transmission spectrum are observed, compared to the previously studied composite particle tunnelling with no magnetic field. Splitting of energy levels in a magnetic field leads to splitting of transmission probability resonances, which are a generic feature of composite particle tunnelling. Magnetic field also induces precession of spin on the Bloch sphere, that can be used as a Larmor clock for measuring tunnelling time. [ABSTRACT FROM AUTHOR]

Dynamical association of Efimov trimers in thermal gases by means of modulated magnetic fields has proven very fruitful in determining the binding energy of trimers. The latter was extracted from the number of remaining atoms, which featured oscillatory fringes stemming from the superposition of trimers with atom-dimers. Subsequent theoretical investigations utilizing the time-dependent three-body problem revealed additional association mechanisms, manifested as superpositions of the Efimov state with the trap states and the latter with atom-dimers. The three atoms were initialized in a way to emulate a thermal gas with uniform density. Here, this analysis is extended by taking into account the effects of the density profile of a semi-classical thermal gas. The supersposition of the Efimov trimer with the first atom-dimer remains the same, while the frequencies of highly oscillatory fringes shift to lower values. The latter refer to the frequencies of trimers and atom-dimers in free space since the density profile smears out the contribution of trap states. [ABSTRACT FROM AUTHOR]

Holmium orthophosphate (HoPO4) was prepared using the solid-state method. The XRD pattern analyses have proved that HoPO4 crystallises in the tetragonal structure (I41 / amd). The maximum magnetic entropy change (− Δ S M max) and the relative cooling power (RCP) reach 34.5 J / kg·K and 414.84 J kg−1 at 2.4 K under a magnetic field of 50 kOe, respectively. The lowest transition temperature and the large magnetocaloric effect (MCE) showed that HoPO4 is a potential candidate for superfluid helium magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

The Himalayas are a region of geomagnetic importance, as they impact the geomagnetic field of Earth and space weather, as it is one of the largest mountain belts in the world. Due to its huge mass, it may influence the dynamics of the Earth's core, the primary source of the geomagnetic field. In Indian longitudes, the mean location of the solar quiet (Sq) focus lies in latitudes closer to the Hanle region. Therefore, monitoring the magnetic field in the Hanle region is important. Ideally, a zero magnetic gradient or low magnetic gradient of the order of a few nT/m or less is preferred; this low gradient helps reduce the effects of local magnetic variations. Hence, to establish a continuous geomagnetic observation setup, a magnetic survey was conducted at Hanle, Ladakh, to identify the location of the low magnetic gradient. From the magnetic survey, the eastern part of the selected hillock was identified that has the least magnetic gradient. After checking other logistics, the chosen site is suitable for setting magnetic field observations. The proposed magnetic observatory at Hanle will be useful for studies related to unusual space weather phenomena, such as the citing of Auroras (of 22–23 April 2023 and 10–11 May 2024) in the Ladakh region, geomagnetic field monitoring in low-mid transitional regions, or magnetic exploration. [ABSTRACT FROM AUTHOR]

Holmium orthophosphate (HoPO4) was prepared using the solid-state method. The XRD pattern analyses have proved that HoPO4 crystallises in the tetragonal structure (I41 / amd). The maximum magnetic entropy change (− Δ S M max) and the relative cooling power (RCP) reach 34.5 J / kg·K and 414.84 J kg−1 at 2.4 K under a magnetic field of 50 kOe, respectively. The lowest transition temperature and the large magnetocaloric effect (MCE) showed that HoPO4 is a potential candidate for superfluid helium magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

This research investigated the effects of magnetic field intensity and frequency on the microstructure and mechanical characteristics of Ti-6Al-4V welding using magnetically controlled narrow gap TIG with a variety magnetic field parameters. The effects of magnetic field intensity and magnetic field frequency on the microstructure and mechanical properties of Ti-6Al-4V joint were studied. It is shown that primary α and β phases make up the base metal's (BM) microstructures in the joint. The microstructure of the fusion zone (FZ) in all welding conditions comprises of acicular α′ and acicular α with various contents and sizes. The weld width grows and the depth of fusion reduces as the magnetic field strength increases due to the Lorentz force's increased energy distribution to the side wall. When the magnetic field frequency rises, the arc's residence time on the side wall decreases, resulting in a reduction in weld breadth and an increase in fusion depth. Martensite content and size can be impacted by magnetic field intensity and frequency, and the rule was constant. This was related to the stirring effect of magnetic field on molten pool and the thermal effect of induced current. The optimum mechanical characteristics for the Ti-6Al-4V joint were attained when the magnetic field intensity and frequency was 6.5 mT and 10 Hz, respectively. At this time, the average hardness of FZ (330.8 HV) and heat affected zone (331.6 HV) were higher than that of BM (316.3 HV). The tensile strength of the joint can reach 95.79% of the BM. This work provides an instructive path for efficient welding of large-thickness titanium alloys. [ABSTRACT FROM AUTHOR]

Neuroinflammation, triggered by aberrantly activated microglia, is widely recognized as a key contributor to the initiation and progression of Alzheimer's disease (AD). Microglial activation in the central nervous system (CNS) can be classified into two distinct phenotypes: the pro-inflammatory M1 phenotype and the anti-inflammatory M2 phenotype. In this study, we investigated the effects of a non-invasive rotating magnetic field (RMF) (0.2T, 4Hz) on cognitive and memory impairments in a sporadic AD model of female Kunming mice induced by AlCl3 and D-gal. Our findings revealed significant improvements in cognitive and memory impairments following RMF treatment. Furthermore, RMF treatment led to reduced amyloid-beta (Aβ) deposition, mitigated damage to hippocampal morphology, prevented synaptic and neuronal loss, and alleviated cell apoptosis in the hippocampus and cortex of AD mice. Notably, RMF treatment ameliorated neuroinflammation, facilitated the transition of microglial polarization from M1 to M2, and inhibited the NF-кB/MAPK pathway. Additionally, RMF treatment resulted in reduced aluminum deposition in the brains of AD mice. In cellular experiments, RMF promoted the M1-M2 polarization transition and enhanced amyloid phagocytosis in cultured BV2 cells while inhibiting the TLR4/NF-кB/MAPK pathway. Collectively, these results demonstrate that RMF improves memory and cognitive impairments in a sporadic AD model, potentially by promoting the M1 to M2 transition of microglial polarization through inhibition of the NF-кB/MAPK signaling pathway. These findings suggest the promising therapeutic applications of RMF in the clinical treatment of AD. [ABSTRACT FROM AUTHOR]