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• Centimeter-level Co long fibers (Co-lf) consistently exhibited higher permittivity than Co particles and Co short fibers due to the enhancement of the effective EM coupling. • A template method is applied to fabricate Co 2 P with inheritance morphology to further confirm the influence of anisotropic structure on the dielectric and microwave absorption performance. • A well-designed phosphorylation process introduces a heterogeneous interface that enriches the type of electromagnetic wave loss while improving the impedance matching to further enhance the EMA properties. Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorption (EMA) at a low filler loading (FL). The construction of one-dimensional magnetic metal fibers (1D-MMFs) contributes to the formation of an electromagnetic (EM) coupling network, enhancing EM properties at a low FL. However, precisely controlling the length of 1D-MMFs to regulate permittivity at low FL poses a challenge. Herein, a novel magnetic field-assisted growth strategy was used to fabricate Co-based fibers with adjustable permittivity and aspect ratios. With a variety of FL changes, centimeter-level Co long fibers (Co-lf) consistently exhibited higher permittivity than Co particles and Co short fibers due to the enhancement of the effective EM coupling. The Co-lf exhibits excellent EMA performance (–54.85 dB, 5.8 GHz) at 10 wt.% FL. Meanwhile, heterogeneous interfaces were introduced to increase the interfacial polarization through a fine phosphorylation design, resulting in elevated EMA performances (–51.50 dB, 6.6 GHz) at 10 wt.% FL for Co 2 P/Co long fibers. This study improves the orderliness of the particle arrangement by regulating the length of 1D-MMFs, which affects the behavior of electrons inside the fibers, providing a new perspective for improving the EMA properties of magnetic materials at a low FL. Significant improvements in dielectric response and electromagnetic absorption performance of ordered magnetic structures fabricated by magnetic field-induced growth [Display omitted] [ABSTRACT FROM AUTHOR]

• Three Gd-based HEOs with perovskite-type structure were designed. • The structural and cryogenic magnetic properties were studied. • Good magnetocaloric performances were observed. • These HEOs are attractive for cryogenic magnetic cooling. Cryogenic magnetic cooling based on the principle of the magnetocaloric effects (MCEs) of magnetic solids has been recognized as an alternative cooling technology due to its significant economic and social benefits. Designing novel magnetic materials with good magnetocaloric performance is a prerequisite for practical applications. In this study, three gadolinium-transition metal-based high entropy oxides (HEOs) of Gd(Fe 1/4 Ni 1/4 Al 1/4 Cr 1/4)O 3 , Gd(Fe 1/5 Ni 1/5 Al 1/5 Cr 1/5 Co 1/5)O 3 , and Gd(Fe 1/6 Ni 1/6 Al 1/6 Cr 1/6 Co 1/6 Mn 1/6)O 3 were designed and systematically characterized regarding their structural and cryogenic magnetic properties. These HEOs were confirmed to crystallize into a single-phase perovskite-type orthorhombic structure with a homogeneous microstructure, reveal a second-order magnetic transition at low temperatures, and exhibit significant cryogenic MCEs. The magnetocaloric performances of the present HEOs, identified by magnetic entropy changes, relative cooling power, and temperature-averaged entropy changes, were comparable with recently reported candidate materials. The present study indicates potential applications for cryogenic magnetic cooling of the present HEOs and provides meaningful clues for designing and exploring HEOs with good cryogenic magnetocaloric performances. [Display omitted] [ABSTRACT FROM AUTHOR]

• The magnetic domains of grain boundary diffused DMP (Nd, Ce)-Fe-B sintered magnets are revealed by MFM to construct the correlation of micromagnetic structure and magnetic properties. • After GBDP, more grains exhibit single-domain characteristics in the remanent state instead of the forked domain patterns of a non-diffused DMP magnet. • The grains in GBDP dual-main-phase magnets that undergo demagnetization first are Ce-rich and Nd-rich grains, which is different from that of non-diffused magnets. • GBDP could effectively complement the disadvantage of anisotropy of the Ce-rich grains of DMP (Nd, Ce)-Fe-B magnets, providing a good experimental case for the process preparation in the subsequent research. The combination of dual-main-phase (DMP) (Nd, Ce)-Fe-B magnets and grain boundary diffusion process (GBDP) is currently a research topic for obtaining high-cost performance materials in rare earth permanent magnet fields. The novel structural features of GBDP (Nd, Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets. In this work, the in-situ magnetic domain evolution of the DMP magnets was observed at elevated temperatures, and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase (Nd, Ce)-Fe-B magnets are discussed. The results show that the shell composition of different types of grains in DMP magnets is similar, while the magnetic microstructure results indicate the Ce-rich grains tend to demagnetize first. Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field, which enhances the coercivity. It is found that much more grains exhibit single domain characteristics in the remanent state for GBDP dual-main-phase (Nd, Ce)-Fe-B magnets. In addition, the grains that undergo demagnetization first are Ce-rich or Nd-rich grains, which is different from that of non-diffused magnets. These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work, providing a new perspective and understanding of the performance improvement of magnetic materials. The novel structural features of GBDP (Nd, Ce)-Fe-B magnets give a version of different domain reversal processes from those of non-diffused magnets. In this work, the in-situ magnetic domain evolution of the dual-main-phase magnets was observed at elevated temperatures, and the temperature demagnetization and coercivity mechanism of the GBDP dual-main-phase (Nd, Ce)-Fe-B magnets are discussed. The magnetic microstructure results indicate the Ce-rich grains tending to demagnetize first. Dy-rich shell with a high anisotropic field caused by GBDP leads to an increase in the nucleation field, which enhances the coercivity. The reflection in the magnetic domain is that more grains exhibit single-domain characteristics in the remanent state. In addition, the grains that undergo demagnetization first are Ce-rich and Nd-rich grains, which is different from that of non-diffused magnets. These results were not found in previous studies but can be intuitively characterized from the perspective of magnetic domains in this work, providing a new perspective and understanding of the performance improvement of magnetic materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is the identification of the magnetic characteristics of the induction load by means of the B–H curve proposed by Fröhlich. Design/methodology/approach: An electromagnetic description of the inductor system is performed to substitute the effects of the induction load, for a mathematical condition, the so-called impedance boundary condition (IBC). Findings: A significant reduction in the computational cost of electromagnetic simulation has been achieved through the use of the IBC, resulting in a computation time approximately 400 times faster than time domain simulation. Moreover, an alternative method has been developed to experimentally identify the parameters that determine the magnetic behavior of the induction load. Finally, further research has been conducted to understand the relationship between the equivalent impedance of an induction load and the excitation current level. Practical implications: This work is performed to achieve a better understanding of the fundamentals involved in the electromagnetic modeling of an induction heating system. Originality/value: This paper introduces the dependence on the excitation level based on a first harmonic approximation and extends the IBC to nonlinear magnetic materials which allows the identification of the magnetic characteristics of the induction load. [ABSTRACT FROM AUTHOR]

Researchers at McGill University have discovered that ultra-thin flakes of bismuth exhibit unique magnetic properties, potentially making the metal a valuable material for eco-friendly electronics. By developing a new technique to create extremely thin bismuth flakes, the researchers were able to observe consistent electromagnetic behavior, known as the anomalous Hall effect, under various conditions. This surprising finding could lead to advancements in electronic technology, as bismuth is less toxic than other materials with similar properties. [Extracted from the article]

Purpose: Performing accurate numerical simulations of electrical drives, the precise knowledge of the local magnetic material properties is of utmost importance. Due to the various manufacturing steps, e.g. heat treatment or cutting techniques, the magnetic material properties can strongly vary locally, and the assumption of homogenized global material parameters is no longer feasible. This paper aims to present the general methodology and two different solution strategies for determining the local magnetic material properties using reference and simulation data. Design/methodology/approach: The general methodology combines methods based on measurement, numerical simulation and solving an inverse problem. Therefore, a sensor-actuator system is used to characterize electrical steel sheets locally. Based on the measurement data and results from the finite element simulation, the inverse problem is solved with two different solution strategies. The first one is a quasi Newton method (QNM) using Broyden's update formula to approximate the Jacobian and the second is an adjoint method. For comparison of both methods regarding convergence and efficiency, an artificial example with a linear material model is considered. Findings: The QNM and the adjoint method show similar convergence behavior for two different cutting-edge effects. Furthermore, considering a priori information improved the convergence rate. However, no impact on the stability and the remaining error is observed. Originality/value: The presented methodology enables a fast and simple determination of the local magnetic material properties of electrical steel sheets without the need for a large number of samples or special preparation procedures. [ABSTRACT FROM AUTHOR]

This paper proposes a new method for determining the simulation parameters of the Jiles–Atherton Model used to simulate the first magnetisation curve and hysteresis loop in ferromagnetic materials. The Jiles–Atherton Model is an important tool in engineering applications due to its relatively simple differential formulation. However, determining the simulation parameters for the anhysteretic curve is challenging. Several methods have been proposed, primarily based on mathematical aspects of the anhysteretic and first magnetisation curves and hysteresis loops. This paper focuses on finding the magnetic moments of the material, which are used to define the simulation parameters for its anhysteretic curve. The proposed method involves using the susceptibility of the material and a linear approximation of a paramagnet to find the magnetic moments. The simulation parameters can then be found based on the magnetic moments. The method is validated theoretically and experimentally and offers a more physical approach to finding simulation parameters for the anhysteretic curve and a simplified way of determining the magnetic moments of the material. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to analyze the influence of welding-induced mechanical stress of a magnetic core material on the performance behavior of a permanent magnet excited synchronous machine (PMSM). Welding, interlocking, clinching and the use of adhesives are state-of-the-art packaging technologies used in the manufacturing of electrical machines. However, the packaging processes degrade the electromagnetic properties of the electric steel sheets, thereby decreasing the performance and achievable range of the electric vehicle. Design/methodology/approach: In this paper, an approach that maps the local changes in magnetic properties due to welding induced stress with the stress values is developed. The welding process induces internal stress inside the steel sheet due to the diffusion of thermal energy into the sheets. Other effects are the changes in the micro structures of the steel sheets (grain sizes). These induced mechanical stresses lead to significant deterioration of the electromagnetic properties. They also lead to an increase in iron loss attributed to steel lamination. Findings: A low speed (city), a high-speed (highway) and WLTC-c3 driving cycle will be used to analyze the effects of the induced stresses on the machine efficiency at the different operating conditions. A high-speed PMSM with a maximum speed of 26,000 min−1 and maximum torque of 130 Nm is designed for this study. Originality/value: The value of this study is in the development of a local varying modeling approach that analyses the influence of weld-induced stress on the performance of electrical machines. Its originality is evident in the mapping methodology. This will enable an application dependent improvement possibilities due to the understanding of the impact of weld-induced stress on the electromagnetic properties of weld-packaged core. [ABSTRACT FROM AUTHOR]

• The saturated magnetization of Fe-based amorphous alloys exhibit higher sensitivity to thermal disturbances. • The amorphous stacking structure exhibits a break in the matrix near the eutectic composition based on the magnetic and thermodynamic analysis. • The unique Fe–B bond pair distribution feature of the metastable Fe 3 B phase may be the structural origin of the amorphous nature. The intrinsic heterogeneity of an amorphous structure originates from composition, and the structure determines the magnetic properties and crystallization models of amorphous magnets. Based on classical Fe–B binary magnetic amorphous alloys, the relationship between the structure and magnetic properties was extensively studied. The stacking structure of Fe–B binary amorphous alloys exhibit discontinuous changes within the range of 74–87 at.% Fe. The structural feature can be expressed as Amor. Fe 3 B matrix + Fe atoms are transforming into Amor. Fe matrix + B atoms with the increase of Fe content. The solute atoms are uniformly distributed in the amorphous matrix holes, similar to a single-phase solid solution structure. The transition point corresponds to the eutectic crystallization model composition (Fe 82 B 18 to Fe 83 B 17). A high Fe content will amplify magnetic moment sensitivity to temperature. Under a given service temperature, the disturbance effect of magnetic moment self-spinning will offset the beneficial effect of increasing Fe content and induce the saturation magnetization (M s) value to decrease. Binary amorphous Fe–B alloys obtain the maximum Curie temperature near 75 at.% Fe, which is slightly smaller than that of the corresponding metastable Fe 3 B phase, i.e., the amorphous short-range order structure maintains the highest similarity to the Fe 3 B phase. The chemical short-range ordering (SRO) structure of amorphous alloys exhibits heredity to corresponding (meta)stable crystal phases. The unique spatial orientation structure of the metastable Fe 3 B phase is the structural origin of the amorphous nature. This study can guide the composition design of Fe-metalloid magnetic amorphous alloys. The design of materials with excellent magnetic properties originates from a deep understanding of precise composition control and temperature disturbance mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

• This comprehensive review provides a comprehensive overview of MXene-based absorbing materials, enabling readers to quickly grasp the research advancements, fundamental theories, and concepts in this field. • This review critically analyzes and evaluates existing research, facilitating a deep understanding of MXene-based absorbing materials, and assisting readers in gaining insights into the research landscape. • The review highlights the limitations of current research and offers a forward-looking perspective on the main directions for future investigations, providing readers with guidance for their further research endeavors. Due to the rapid development of radar technology, the demand for absorbing stealth materials is increasing, and ultra-broadband absorption (effective absorption bandwidth > 8 GHz) has become an inevitable requirement. As a new type of two-dimensional material, MXene material possesses the characteristics of excellent wave absorbing material due to its easy preparation, easy modulation of defects and surface functional groups, and high conductivity. This work summarizes the absorbing theory and research progress on MXene-based absorbing materials in recent years, including pure MXene absorbing materials and MXene-based magnetic or dielectric composite materials with multiple losses. Some shortcomings and research directions of MXene-based materials were pointed out. Currently, research on MXene-based absorbent materials is thriving and in a state of vigorous development. Excellent absorbent materials have been reported, but their shortcomings are also apparent. The factors that affect the performance of MXene-based absorbent materials are complex, and the absorption mechanism is relatively simple. Further systematic and detailed research is needed to clarify these influencing mechanisms, broaden the absorption bandwidth, and reduce the matching thickness to meet practical usage requirements in the future. [ABSTRACT FROM AUTHOR]

• A novel γ′ -Fe 4 N based soft magnetic material with high resistance and high saturation magnetization was fabricated through the SPS process. • The nitriding mechanism under various nitriding temperature and nitriding time was explored, and the evolution of nitrogen and oxygen content and magnetic properties with nitriding temperature and nitriding time were investigated. • A high resistance oxide interface composed of ZnO or TiO 2 was established in the γ′ -Fe 4 N bulk magnetic material through a series of pre-calcination, reduction, and nitridation steps. ZnO doped γ′ -Fe 4 N bulk material has a maximum resistivity of 220 μΩ cm, accompanied by a high m s of 156.02 emu/g. While the TiO 2 doped γ' -Fe 4 N exhibits a remarkable resistivity of 379 μΩ cm and a m s of 149.7 emu/g. In addition, oxide interface engineering can well block the formation of ε -Fe 3 N phase, so as to better maintain the excellent magnetic properties. • The innovative design concept of this novel γ′ -Fe 4 N based soft magnetic material has opened up new possibilities for the development of soft magnetic materials with exceptional electrical and magnetic properties, which provides a promising path towards the creation of a new generation of soft magnetic materials for the advanced power equipment. Soft magnetic material with high saturation magnetization (M s) and high resistance (ρ) is vital to improve the power density and conversion efficient of modern electrical magnetic equipment. Yet, increasing M s is always at the expense of high resistivity, such as soft magnetic alloys substitute for the ferrite. In this work, the superior comprehensive electromagnetic properties, namely the close association of high saturation magnetization and high resistivity, are combined in a new way in a newly Fe-N based magnetic materials. A high resistance oxide interface engineering was constructed between the conducting ferromagnetic phases in the process of spark plasma sintering (SPS) to achieve superior electromagnetic properties. The ZnO composite γ' -Fe 4 N bulk has a maximum resistivity of 220 μΩ cm and a M s of up to 156.02 emu/g, while the TiO 2 composite γ' -Fe 4 N bulk has a maximum resistivity of 379 μΩ cm and a M s of 149.7 emu/g. The research findings offer valuable insights for the advancement of the next generation of soft magnetic materials, which hold significant potential for use in high-frequency, high-efficiency, and energy-saving power equipment applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• The fabricated magnetic NiFe 2 O 4 @FeNi 3 core-shell nanospheres anchored on rGO nanosheets endow the material with both dielectric and magnetic loss simultaneously. • The electromagnetic parameters of the materials can be adjusted by regulating the mass ratio of LDH to GO as well as the annealing temperature. • The fabricated LDH-rGO aerogels possess the merits of broad bandwidth, strong absorption, lightweight, thin matching thickness, low filling content and low density. • The EMW absorption properties of materials in the real far field conditions are verified via the Computer Simulation Technology and the Radar Cross-Sectional simulation. Graphene has been extensively utilized in the domain of electromagnetic wave (EMW) absorption materials because of its excellent electrical conductivity. However, the inferior impedance matching performance and the single loss mechanism vastly restrict the application. Hence, it's an effective strategy to solve these issues by introducing magnetic components. Notably, layer double hydroxide (LDH) is an appropriate template to obtain magnetic component materials. Considering that ferromagnetic metals such as Fe, Co, Ni, and their corresponding metal oxides are usually treated as magnetic components which are promising candidates for EMW absorption materials. Therefore, in this work, a FeNi-layered double hydroxide-reduced graphene oxide (FeNi-LDH-rGO) aerogel was synthesized through a series of processes such as electrostatic self-assembly, hydrothermal, freeze-drying, and annealing. The magnetic NiFe 2 O 4 @FeNi 3 core-shell nanospheres were obtained from FeNi-LDH precursor, anchoring on rGO nanosheets after the annealing treatment. Furthermore, the effects of different mass ratios of LDH to GO as well as different annealing temperatures of LDH-rGO aerogel on the EMW absorption property and impedance matching performance were explored. As a consequence, the fabricated ultralight 600LDH-rGO 2:1 aerogel shows a broad effective absorption bandwidth (EAB) of 7.04 GHz at a thickness of 2.3 mm with a low filling content of only 6 wt% and a low density of 4.4 mg/cm3. In conclusion, the synthetic LDH-rGO aerogels offer an effective strategy for preparing EMW absorption materials that own three-dimensional porous network structure and unique magnetic NiFe 2 O 4 @FeNi 3 core-shell structure nanospheres. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: The accurate modeling of magnetic hysteresis in electrical steels is important in several electrical and electronic applications. Numerical models have long been known that can correctly reproduce some typical behaviours of these magnetic materials. Among these, the model proposed by Jiles and Atherton must certainly be mentioned. This model is intuitive and fairly easy to implement and identify with relatively few experimental data. Also, for this reason, it has been extensively studied in different formulations. The developments and numerical tests made on this hysteresis model have indicated that it is able to accurately reproduce symmetrical cycles, especially the major loop, but often it fails to reproduce non-symmetrical cycles. This paper aims to show the positive aspects and highlight the defects of the different formulations in predicting the minor loops of electrical steels excited by non-sinusoidal currents. Design/methodology/approach: The different formulations are applied to different electrical steels, and the data coming from the simulations are compared with those measured experimentally. The direct and inverse Jiles–Atherton models, including the introduction of the dissipative factor approach, are presented, and their limitations are proposed and validated using the measurements of three non-grain-oriented materials. Only the measured major loop is used to identify the parameters of the Jiles–Atherton model. Furthermore, the direct and inverse Jiles–Atherton models were used to simulate the minor loops as well as the hysteresis cycles with direct component (DC) bias excitation. Finally, the simulation results are discussed and compared to measurements for each study case. Findings: The paper indicates that both the direct and the inverse Jiles–Atherton model formulations provide a good agreement with the experimental data for the major loop representation; nevertheless, both models can not accurately predict the minor loops even when the modification approaches proposed in the literature were implemented. Originality/value: The Jiles–Atherton model and its modifications are widely discussed in the literature; however, some limitations of the model and its modification in the case of the distorted current waveform are not completely highlighted. Furthermore, this paper contains an original discussion on the accuracy of the prediction of minor loops from distorted current waveforms, including DC bias. [ABSTRACT FROM AUTHOR]

• Co 4 Fe 2 Al x Mn y alloys were designed to develop HEAs with good magnetic properties. • Co 4 Fe 2 Al 1.5 Mn 1.5 HEA has the highest m s of 161.3 emu g–1 in developed HEAs. • Mn shift from antiferromagnetic to ferromagnetic with the help of Al. • Co 4 Fe 2 Al 1.5 Mn 1.5 HEA has a structure of the B2 phase distributed in the DO 3 matrix. • Co 4 Fe 2 Al 1.5 Mn 1.5 HEA has good temperature stability up to 600 °C. High-entropy alloys (HEAs), which are composed of 3d transition metals such as Fe, Co, and Ni, exhibit an exceptional combination of magnetic and other properties; however, the addition of non-ferromagnetic elements always negatively affects the saturation magnetization strength (M s). Co 4 Fe 2 Al x Mn y alloys were designed and investigated in this study to develop a novel HEA with excellent soft magnetic properties. The Co 4 Fe 2 Al 1.5 Mn 1.5 HEA possesses the highest M s of 161.3 emu g–1 thus far reported for magnetic HEAs, a low coercivity of 1.9 Oe, a high electrical resistivity of 173 μΩ cm, a superior thermal stability up to 600 °C, which originates from the novel microstructure of B2 nanoparticles distributed in a DO 3 matrix phase, and the crucial transition of Mn from antiferromagnetism to ferromagnetism with the assistance of Al. The Co 4 Fe 2 Al 1.5 Mn 1.5 HEA was selected to produce micron-sized powder and soft magnetic powder cores (SMPCs) for application in the exploration field. The SMPCs exhibit a high stable effective permeability of 35.9 up to 1 MHz, low core loss of 38.1 mW cm–3 (@100 kHz, 20 mT), and an excellent direct current (DC) bias performance of 87.7% at 100 Oe. This study paves the way for the development of soft magnetic HEAs with promising applications as magnetic functional materials. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to exploit the optimal performances of each magnetic material in terms of low iron losses and high saturation flux density to improve the efficiency and the power density of the selected motor. Design/methodology/approach: This paper presents a study to improve the power density and efficiency of e-motors for electric traction applications with high operating speed. The studied machine is a yokeless-stator axial flux permanent magnet synchronous motor with a dual rotor. The methodology consists in using different magnetic materials for an optimal design of the stator and rotor magnetic circuits to improve the motor performance. The candidate magnetic materials, adapted to the constraints of e-mobility, are made of thin laminations of Si-Fe nonoriented grain electrical steel, Si-Fe grain-oriented electrical steel (GOES) and iron-cobalt Permendur electrical steel (Co-Fe). Findings: The mixed GOES-Co-Fe structure allows to reach 10 kW/kg in rated power density and a high efficiency in city driving conditions. This structure allows to make the powertrain less energy consuming in the battery electric vehicles and to reduce CO2 emissions in hybrid electric vehicles. Originality/value: The originality of this study lies in the improvement of both power density and efficiency of the electric motor in automotive application by using different magnetic materials through a multiobjective optimization. [ABSTRACT FROM AUTHOR]

• Polycrystalline Er 1-x Tm x Al 2 (0 ≤ x ≤ 1) compounds were synthesized successfully. • The working temperature covers the range from 16.0 K to 3.6 K. • Er 1-x Tm x Al 2 (0 ≤ x ≤ 1) compounds show giant low-field MCE. • Magnetic structure was confirmed based on neutron powder diffraction experiment. Magnetocaloric material is the key working substance for magnetic refrigerant technology, for which the low-field and low-temperature magnetocaloric effect (MCE) performance is of great importance for practical applications at low temperatures. Here, a giant low-field magnetocaloric effect in ferromagnetically ordered Er 1– x Tm x Al 2 (0 ≤ x ≤ 1) compounds was reported, and the magnetic structure was characterized based on low-temperature neutron powder diffraction. With increasing Tm content from 0 to 1, the Curie temperature of Er 1– x Tm x Al 2 (0 ≤ x ≤ 1) compounds decreases from 16.0 K to 3.6 K. For Er 0.7 Tm 0.3 Al 2 compound, it showed the largest low-field magnetic entropy change (–Δ S M) with the peak value of 17.2 and 25.7 J/(kg K) for 0–1 T and 0–2 T, respectively. The (–Δ S M) max up to 17.2 J/(kg K) of Er 0.7 Tm 0.3 Al 2 compound for 0–1 T is the largest among the intermetallic magnetocaloric materials ever reported at temperatures below 20 K. The peak value of adiabatic temperature change (Δ T ad) max was determined as 4.13 K and 6.87 K for 0–1 T and 0–2 T, respectively. The characteristic of second-order magnetic transitions was confirmed on basis of Arrott plots, the quantitative criterion of exponent n , rescaled universal curves, and the mean-field theory criterion. The outstanding low-field MCE performance with low working temperatures indicates that Er 1– x Tm x Al 2 (0 ≤ x ≤ 1) compounds are promising candidates for magnetic cooling materials at liquid hydrogen and liquid helium temperatures. The magnetic transition temperature of Er1-xTmxAl2 (0 ≤ x ≤ 1) compounds was decreased from 16.0 K to 3.6 K monotonically with increasing Tm content. Magnetic structure of Er0.7Tm0.3Al2 compound with rare earth atomic magnetic moments arranging along 〈111〉 direction was confirmed for the first time based on neutron powder diffraction experiment. Giant MCE was obtained among which Er0.7Tm0.3Al2 compound shows the largest (-ΔSM)max with the value of 17.2 J/kg K for 0–1 T compared with ever reported low temperature intermetallic MCE materials below 20 K. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel stress-induced method is put forward to fabricate magnetoelectric device. • Stress controlling magnetic behavior has been directly imaged. Stress induction plays a special role in performance control for material science. So far, it has remained challenging to systematically investigate magnetoelectric effect under stress-mediated interaction. Here we constructed a magnetoelectric device with piezoelectric stress induction, in which the stress plays a crucial intermediate role during the controllable modification of the magnetic behavior transitions under the magnetic field or current pulse driven process. The compressive stress was found to make the above process easier and reduce energy consumption via changing the magnetic domain energy state. Meanwhile, both the domain distribution and domain-wall driven process are sensitive to stress intensity. Our magnetoelectric device integrated the advantages of voltage-stress and spin-current for the control of magnetic behavior transition with the help of micro-nano processing. For the stress-induced magnetic behavior in magnetic materials was directly imaged and quantificationally investigated, the complex interactions between stress, magnetic domain motion, magnetic field, and spin current have been clarified. [ABSTRACT FROM AUTHOR]

The noble metal Pt is an ideal catalyst for promoting the hydrogen evolution reaction (HER) during the electrolysis of water. However, Pt is also expensive and suffers from low utilization rates. In this work, a Pt-Ni 2 P/NF nanorod catalyst with a low Pt loading was synthesized under different magnetic fields, and it was found that the application of a magnetic field can increase the rate of the galvanic replacement reaction. When the magnetic field strength increases from 0 to 600 mT, the chemical reaction rate increases gradually, and the utilization rate of Pt increased by 2.3 times under 600 mT. The mechanism of the magnetic field-induced magnetohydrodynamic (MHD) effect on the galvanic replacement reaction was revealed. In a 1 M KOH solution and at a current density of 10 mA cm–2, the overpotential of Pt-Ni 2 P/NF prepared by applying a 600 mT magnetic field was as low as 15 mV and the Tafel slope was 37 mV dec–1, compared with values of 82 mV and 70 mV dec–1 for a specimen prepared without a magnetic field. Additionally, at an overpotential of 90 mV, the mass-based Pt activity of the former material was 12 times greater while its turnover frequency was 19 times greater. This work provides theoretical and technical knowledge expected to assist in the controllable preparation of materials in magnetic fields and the efficient utilization of metallic resources. [Display omitted] [ABSTRACT FROM AUTHOR]

The patent issued by Toppan Inc. introduces a new method for producing composite particles that include a core particle containing at least one polymer and a fine fiber layer formed of fine fibers on the surface of the core particle. The composite particles are bonded in an inseparable state, with an ionic functional group content ranging from 0.0002 mmol/g to 0.5 mmol/g. This innovation aims to provide a new handling mode for cellulose nanofibers and chitin nanofibers, offering enhanced functionality and ease of use in various applications. [Extracted from the article]

A patent has been issued for an electromagnetic field generator by RadWave Technologies Inc, designed to reduce X-ray radiation dose during medical procedures. The generator is compatible with fluoroscopic imaging and can be placed around the patient without impacting image quality. The system includes antenna elements on a printed circuit board with conducting metal traces, enclosed in a non-conductive material to minimize interference and improve tracking accuracy. [Extracted from the article]

A patent application by inventor Takeshi Nakayama for a magnetic resonance imaging apparatus and operation method has been filed and assigned to FUJIFILM Healthcare Corporation. The invention aims to accurately detect magnetic materials in the imaging space of an MRI apparatus and its vicinity using a superconducting coil. By energizing the coil with a specific current, the presence of magnetic materials can be detected with high accuracy, simplifying the device configuration. The invention addresses the limitations of existing techniques and provides a novel approach to magnetic material detection in MRI imaging. [Extracted from the article]

Researchers from Fudan University in Shanghai, China, have conducted a study on core-shell magnetic particles, focusing on their synthesis and applications in various fields such as catalysis, biomedicine, and environmental remediation. The study highlights the importance of surface engineering strategies to enhance the properties of these particles and discusses the potential applications of core-shell assembly chemistry in bioimaging, diagnosis, and smart catalysis. The research also addresses future challenges, directions, and applications for core-shell magnetic particles. For more information, readers can refer to the Chemical Reviews journal article by contacting the authors listed in the document. [Extracted from the article]

A patent application titled "Cochlear Implants Having MRI-Compatible Magnet Apparatus And Associated Systems And Methods" was published online by inventors Lee and Smith. The application focuses on improving cochlear implant systems by introducing MRI-compatible magnet apparatus that reduce torque and MRI artifacts. The new design includes only two elongate diametrically magnetized magnets, enhancing efficiency and reducing manufacturing costs. This innovation aims to enhance the functionality and compatibility of cochlear implants with MRI systems. [Extracted from the article]

A recent study from the University of Science and Technology China explores the design of magnetic soft robots inspired by annelids. The research introduces a multimodal unit programming method for efficient design of magnetic soft materials, simplifying complex deformations into single units. This approach allows for specific deformation modes and operations at different scales, showcasing the potential of magnetic soft materials for various applications. The study was supported by various research funds and has been peer-reviewed, providing valuable insights into the field of robotics and emerging technologies. [Extracted from the article]

Researchers Arai, Hamada, and Kashiwa have submitted a patent application for a "Coil Component" aimed at addressing the demand for smaller and more efficient electronic components. The invention focuses on creating a smaller coil component with an insulation layer to enhance performance. By utilizing magnetic metal materials and innovative design features, the coil component aims to achieve miniaturization without compromising functionality. The patent application outlines specific details and claims related to the design and construction of the coil component. [Extracted from the article]

Researchers Sharma, Singh, and Sukhatme have submitted a patent application for a "Continuous Suction And Reperfusion Mechanism" to Boston Scientific Medical Device Limited. The patent application describes a suction device with various components and mechanisms for fluid control in medical devices. The inventors aim to provide alternative medical devices and manufacturing methods to address existing advantages and disadvantages in the field. The patent application outlines different examples of the suction device and its components, emphasizing the need for innovation in medical device technology. [Extracted from the article]

A recent study conducted by researchers at Complutense University Madrid focused on the structural, magnetic, and colloidal stability of iron oxide samples prepared with different surfactants. The study aimed to investigate the behavior of these samples for potential applications in biomedicine. The research found that the silica-coated samples showed the best stability and dispersibility, making them suitable for future use. This peer-reviewed study provides valuable insights into the development of magnetic materials for biomedical purposes. [Extracted from the article]

A study conducted at Kyushu University in Fukuoka, Japan, explored the use of topology-based radiomic features in magnetic resonance images to predict the malignancy grade of parotid gland cancer (PGC). The research found that topology-based radiomic features could be feasible for noninvasive prediction of PGC malignancy grade, with an accuracy of 0.975 in validation cases compared to 0.694 in conventional approaches. The study was supported by Grants-in-Aid for Scientific Research (KAKENHI) and has been peer-reviewed, offering valuable insights into cancer research and imaging techniques. [Extracted from the article]

A patent application by Jeremy Madvin from Westlake Village, CA, US, for "Jewelry With Embedded Rotatable Magnets" is currently in the approval process with the USPTO. The invention aims to provide jewelry articles with built-in or attached magnets that, when spun, release a deeper healing magnetic field. This innovative approach combines therapeutic and aesthetic value in various jewelry forms like bracelets, necklaces, charms, pendants, anklets, and rings. The patent application highlights the unique features of the invention and its potential to offer a new dimension to magnetic therapy in jewelry. [Extracted from the article]

A recent study conducted at Southeast University in Jiangsu, China, focused on enhancing the magnetic properties of iron-based nanoparticles through the coprecipitation method and doping them with various ions. The research found that Zn-doped nanoparticles with a 0.6 ratio exhibited the highest saturation magnetization intensity and r2 values, making them effective as T2 MRI contrast agents. The study also revealed a formation mechanism for ion-doped magnetic iron-based nanoparticles, which could lead to the development of improved nanoparticles for biomedical applications. The research has been peer-reviewed and published in the Journal of Magnetism and Magnetic Materials. [Extracted from the article]

• The research progress of MCE in RE 2 TMTM 'O 6 DP oxides is reviewed. • The magnetism, MTP and magnetocaloric performances are summarized. • Some of the Gd 2 TMTM 'O 6 DP oxides are considerable for cryogenic MR. The magnetic functional materials play a particularly important role in our modern society and daily life. The magnetocaloric effect (MCE) is at the basis of a solid state magnetic refrigeration (MR) technology which may enhance the efficiency of cooling systems, both for room temperature and cryogenic applications. Despite numerous experimental and theoretical MCE studies, commercial MR systems are still at developing stage. Designing magnetic solids with outstanding magnetocaloric performances remains therefore a most urgent task. Herein, recent progresses on characterizing the crystal structure, magnetic properties and cryogenic MCE of rare earths (RE)-based RE 2 TMTM 'O 6 double perovskite (DP) oxides, where TM and TM ' are different 3d transition metals, are summarized. Some Gd-based DP oxides are found to exhibit promising cryogenic magnetocaloric performances which make them attractive for active MR applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• 0D CoNi nanoalloy-encapsulated 1D NCNT were grown on 2D Ti 3 C 2 T x sheets. • High surface areas and excellent thermal oxidation stabilities were achieved for the composite. • The minimum RL reached −55.3 dB at 2.1 mm. • The EAB of 4.3 GHz at 1.5 mm could be attained. Recently, two-dimensional MXene materials have attracted numerous attention in electromagnetic wave shielding/absorption. Hybridizing magnetic materials and constructing multi-dimensional structures in MXene is highly beneficial to improve electromagnetic wave absorption properties. Herein, we demonstrate a strategy for in situ growing 0D CoNi nanoalloy-encapsulated 1D N-doped carbon nanotubes on a 2D Ti 3 C 2 T x MXene sheet through an electrostatic assembly process followed by a high-temperature pyrolysis process. The resultant 201-structured MXene-CoNi@N-doped carbon nanotube (MXene-CoNi@NCNT) composites displayed high surface areas (55.6–103.7 m2/g), moderate magnetism (19.8–24.6 emu/g), and excellent thermal oxidation stabilities (≥ 307 °C). In addition, the unique 2D/0D/1D architectures entrusted the composites with abundant interfaces, various defects, and numerous nitrogen dopants. Taking advantage of the special 201 structure and the existence of both magnetic and dielectric loss, the MXene-CoNi@NCNT composite showed great impedance matching and strong attenuation performance. A strong reflection loss of –55.3 dB was achieved when the coating thickness was 2.1 mm, and a wide effective absorption bandwidth of 4.3 GHz was achieved at a thickness of 1.5 mm, much superior to that of similar absorbers. This work demonstrates a novel strategy for designing electromagnetic wave absorbers with magnetic and dielectric losses accompanied by multiple dimensional structures. [ABSTRACT FROM AUTHOR]

Physicists have discovered a new type of magnetic material called altermagnets, which could have applications in faster and more efficient computer hard drives. Altermagnets have a unique structure where the spins of neighboring atoms alternate and are also rotated with respect to one another. This special symmetry puts altermagnets in their own class of magnetic materials. Recent experiments have confirmed the altermagnetic behavior of certain materials, and researchers have identified numerous altermagnet candidates. Altermagnets could potentially overcome the limitations of current magnetic materials and revolutionize technology. [Extracted from the article]

• A novel Co@NC@MoS 2 magnetic hierarchical nanotube is designed and prepared. • The minimum reflection loss (RL min) exceeds −61.97 dB. • The effective absorption bandwidth (EAB) covers 5.6 GHz. • The electromagnetic parameters can be adjusted by changing the load of MoS 2. In this study, a new lightweight one-dimensional absorber Co@NC@MoS 2 was designed and prepared. Firstly, polydopamine (PDA) was coated by oxidative self-polymerization with cobalt-nitrilotriacetic acid chelate nanowires (Co-NTAC) as template. Then core-shell structured magnetic hierarchical nanotubes (Co@PDA@MoS 2) were prepared by one-step hydrothermal method. After thermal annealing, PDA layer was transformed into nitrogen doped carbon layer (NC) to obtain the efficient microwave absorber Co@NC@MoS 2. The removal of template and growth of MoS 2 were completed simultaneously, the preparation process was simplified. Because of its good magnetic loss and dielectric loss, Co@NC@MoS 2 shows excellent microwave absorption performance. Under filler content of 15 wt.%, the minimum reflection loss (RL min) can reach -61.97 dB@9.2 GHz, and the effective absorption bandwidth (EAB) is 5.6 GHz. The electromagnetic parameters of Co@NC@MoS 2 can be further adjusted by changing the load of MoS 2. Meanwhile, the structure and composition of Co@NC@MoS 2 were systematically analyzed. The influence of the microstructure on the microwave absorbing properties was investigated, and the microwave attenuation mechanism is revealed. As an efficient and lightweight absorber, Co@NC@MoS 2 has potential application value in the construction of new stealth coatings. [ABSTRACT FROM AUTHOR]

• CB/Co@C nanocomposites composed of sustainable carbon black and anchored Co@C nanoparticles have been successfully synthesized. • As a novel lightweight electromagnetic wave absorber, the optimal RL min and EAB of -53.989 dB and 6.0 GHz were achieved at thin thickness. • A reasonable absorption mechanism was proposed according to various loss mechanism induced by different components. Recently, developing carbon-based hybrid materials loaded with magnetic components has been generally regarded as a promising and practically feasible strategy when it comes to constructing lightweight electromagnetic wave absorbers. In the current work, reclaimed carbon black (CB) nanopowder was firstly produced by simple burning of wheat straw, which was then employed as sustainable carbon-based host materials (carrier) and successfully decorated Co@C nanoparticles via a simple thermal reduction process. Remarkably, both the as-fabricated nanocomposites and corresponding electromagnetic wave absorption performances could be effectively tuned by tailoring the dosage of the Co@C nanoparticles. The minimum reflection loss (RL min) of –53.989 dB was achieved for CB/Co@C-2# at 2.28 mm thickness, meanwhile, CB/Co@C-3# was featured by a wide effective absorption band (EAB) of 6 GHz (6.72–12.72 GHz) at a 2.73 mm matching thickness, which covered the entire X band, suggesting that the CB/Co@C nanocomposites were an attractive candidate for electromagnetic wave absorber. According to the synergistic influence of dielectric loss and magnetic loss from CB and Co@C, respectively, as well as the properly matched impedance, a reasonable electromagnetic wave attenuation mechanism was illustrated. It is noteworthy that the preparation process of CB is a facile, recycled, and low-cost strategy for achieving nanoscale carbon-based absorbing materials, moreover, the CB/Co@C nanocomposites provide a reference for constructing lightweight dielectric-magnetic products with superb electromagnetic wave absorption performances. [ABSTRACT FROM AUTHOR]

Magnetic materials offer attractive applications in biomedicine with a variety of applications from sensors to diagnosis and treatment. Special attention deserves the nanofeature elements as the nanostructured surfaces or the nanoparticles that have been proposed as alternatives for drug delivery vectors, bactericide treatments, lab-on-a-chip sensors, hyperthermiabased cancer therapy, magnetic bio-separation or emerging magnetic resonance imaging (MRI) contrast agents. [ABSTRACT FROM AUTHOR]

Researchers at I. Javakhishvili Tbilisi State University in Georgia have conducted a study on the resonant method of heating magnetic nanoparticles in hyperthermia for cancer treatment. The study found that by applying a resonant radio frequency field to magnetic nanoparticles, tumor temperatures could be increased by 6 degrees in about 60 seconds, enough to destroy malignant cells while leaving healthy cells unharmed. This research has been peer-reviewed and published in Physica B Condensed Matter. For more information, readers can contact the authors at the university in Tbilisi. [Extracted from the article]

Researchers at Mashhad University of Medical Sciences in Iran have optimized cobalt ferrite magnetic nanoparticles for use as a theranostic agent, combining MRI imaging and hyperthermia. The study focused on synthesizing CoFe2O4@Au@dextran particles and evaluating their magnetic properties. The results suggest that these nanoparticles could enhance contrast-enhanced images and reduce the need for contrast agents, potentially improving efficiency in theranostic applications. The research has been peer-reviewed and published in Magnetic Resonance Materials in Physics, Biology and Medicine. [Extracted from the article]

A recent study from the University of Illinois in Urbana explores the use of magnetic soft materials with continuous magnetization orientations for various applications such as robotics and biomedicine. The research introduces a multiphysics topology optimization framework to enhance design flexibility and performance while eliminating sharp changes in magnetization orientations. The study aims to bridge design optimization and fabrication of magnetic materials with continuously varying magnetization orientations, showcasing the potential for creating innovative designs with multiple functionalities. The research has been peer-reviewed and offers valuable insights into the field of biotechnology. [Extracted from the article]

A study conducted by researchers at ICFAI University Tripura in Agartala, India, explores the use of ultrathin lanthanide-based 2D-coordination nanosheets in tissue engineering. These nanomaterials offer unique properties due to their two-dimensional structure, allowing for various applications in fields such as optoelectronics, sensors, and biomedical analysis. The research highlights the potential of lanthanide-based 2D-coordination nanosheets and discusses their synthetic techniques, characterization methods, and practical applications. The study concludes by addressing the challenges and opportunities in this area of research. [Extracted from the article]

Zhejiang University in China has been granted a patent for a magnetic flexible tactile sensing structure that can detect both the size and position of force, offering a linear relationship between force and magnetic field change. This innovation addresses limitations of traditional tactile sensors by providing a solution for robotic electronic skins and wearable devices. The sensor, based on a folding magnetization method, has broad applications in robotics and offers ease of data processing due to its linear load characteristics. [Extracted from the article]

A patent application titled "Magnetization Device" was published online by inventor Masatomo Ishikawa on October 3, 2024. The patent application, assigned to Asahi Intecc Co. Ltd., focuses on a magnetization device designed to magnetize a linear member, such as medical devices like guide wires, catheters, and injection needles, with high accuracy. The device includes a magnetization yoke and coil to generate a magnetic field for precise magnetization. This innovation aims to address challenges related to magnetizing medical devices inserted into living bodies, enhancing the efficiency and accuracy of the process. [Extracted from the article]

Researchers have submitted a patent application for "Magnetic Nanoparticles For Removal Of Particulate Waste" to address the growing issue of nanoplastic pollution in various environments. The patent application outlines the use of iron-containing nanoparticles to attract and bind plastic waste through adsorption, allowing for efficient removal using an externally applied magnetic field. The method described in the patent application aims to provide a high-throughput and reliable solution for isolating and separating nanoplastics from drinking water, wastewater, and environmental bodies of water. [Extracted from the article]

A recent study published in the journal Health & Medicine Week explores the use of magnetic resonance imaging (MRI) to characterize magnetic inclusions in the subcortex of the brain. The researchers found that the MRI signal decay in brain tissue with magnetic inclusions exhibits a transition from a Gaussian behavior to exponential behavior. By analyzing the non-exponential decay at short times, the researchers were able to gain insight into the properties of the magnetic inclusions, such as size and volume fraction. This research has potential applications in understanding brain microstructure and could be useful in studying conditions like Parkinson's disease. However, it is important to note that this study has not yet undergone peer review. [Extracted from the article]

Inventors Beyers and Bonutti have filed a patent application for a "Magnetic Joint Implant" that utilizes magnets and electric or magnetic fields to treat joints, bones, and other tissues. The implant can perform arthrodiastasis, maintain bone positions, and contain pharmaceutical materials in a specific area. It allows for dynamic control of the magnetic field to compress or distract joints. The patent application describes various materials that can be used, such as neodymium and plastic magnets, and the implants can be shaped in different forms and sizes with porous surfaces or coatings to promote bone growth. External devices can interact with the implants magnetically, enabling joint movement control without direct contact with the skin. The implants can also modify the space defined by soft tissue and aid in the healing process. [Extracted from the article]

Exploring magnetic configurations of magnets often involves utilizing the four-state method to obtain the magnetic interaction matrix, and Monte Carlo method to simulate spin textures and phase transition processes. However, computing the interaction matrix between magnetic atoms using the four-state method requires plenty of individual calculations. Despite manual simplifying the number of individual calculations based on material's symmetry is possible, there remains a necessity for an automated approach to streamline the process for high-throughput screening of magnetic materials. Meanwhile, the traditional sequential Monte Carlo simulation encounters challenges of low efficiency and long time consuming in dealing with large systems. Furthermore, the prior parallelism in the Heisenberg model was limited to parallel computation of the system's energy or run several replicas in parallel. Hence, in our pursuit of comprehensive parallelization for the Heisenberg model, we have introduced a novel adaptation of the checkerboard algorithm, enabling a fully parallelizable simulation of the Heisenberg model. To address these problems, we have developed Sym4state.jl, a program specifically designed to simplify the computation of magnetic interaction matrix and simulate spin textures under various environmental conditions. This program, available as a Julia package, can be freely accessed at https://github.com/A-LOST-WAPITI/Sym4state.jl. Program title: Sym4state.jl CPC Library link to program files: https://doi.org/10.17632/s6dkmgrjfw.1 Developer's repository link: https://github.com/A-LOST-WAPITI/Sym4state.jl Licensing provisions: MIT Programming language: Julia Nature of problem: Employing the four-state method to calculate magnetic interaction matrix for magnetic materials can be simplified based on material symmetry, however, there is a lack of automated approach to streamline the simplification. Additionally, the commonly used Metropolis method for simulating magnetic texture can only make parallel computation of the system's energy or run several replicas in parallel, which could hardly boost the performance when simulating the large-scale magnetic textures. Solution method: We simplify the four-state method calculations by utilizing the principles of energy invariance under symmetry operations and time reversal operations. To enhance the efficiency of the Metropolis algorithm, we have designed a strategy to divide the entire 2D lattice into multiple domains. We then execute the Metropolis algorithm in parallel for each individual domain, thereby improving the overall computational efficiency. Additional comments including restrictions and unusual features: While the methods aimed at simplifying the four-state method and parallelizing the Metropolis algorithm are applicable to both 2D and 3D systems, the current program is specifically designed for the calculation and simulation of magnetism in 2D materials. As a result, compatibility with 3D systems has not yet been implemented. [ABSTRACT FROM AUTHOR]

A patent has been issued to Peking University for a flexible permanent magnetic material that can be used in magnetic biological effect products. The patent addresses the need for magnetic materials that are soft, light, and bendable, while also providing a biomedical-grade magnetic field intensity. The patent describes a method for preparing the flexible permanent magnetic material, which involves mixing raw materials, carrying out defoaming treatment, pouring the mixture into a mold, heating while applying a magnetic field, and then removing the magnetic field to obtain the flexible permanent magnetic material. The patent aims to solve the problems associated with existing magnetic materials used in biomedical applications. [Extracted from the article]

A patent has been issued for an electronic package with an inductor structure of a package carrier. The package includes an insulator with spiral inductor circuits embedded in layers, as well as shielding layers to prevent electromagnetic interference. The package also features a build-up circuit structure and electronic elements connected via fan-out conductive copper pillars. The invention aims to address the challenges faced by conventional inductive elements, such as electromagnetic interference and high processing costs. The patent was filed by Hsu, Che-Wei and assigned to Phoenix Pioneer Technology Co. Ltd. [Extracted from the article]