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Low-damping magnetic insulators like LiFe5O8 have gained considerable attention in recent years for their exceptional properties such as low energy loss and high gyromagnetic ratio, making them suitable in microwave and spintronic fields. However, due to factors such as crystalline quality and stress, the damping behavior of LiFe5O8 thin films falls below expectations. In this work, we utilize miscut substrate to modulate the structure and magnetic properties of LiFe5O8 films. We found that miscut angles can improve the crystalline quality of the film. However, a miscut angle of 6° resulted in a phase transition from tetragonal to orthorhombic in the LiFe5O8 phase. In particular, the out-of-plane ferromagnetic resonance linewidth of the orthorhombic LiFe5O8 (LFO) film was significantly reduced compared to that of the tetragonal LFO film on a non-miscut substrate, which could be attributed to the structural change. The orthorhombic LFO film also exhibited lower damping and a higher in-plane remanence ratio, indicating superior microwave magnetic properties. These findings suggest that miscut strain could be a viable method for improving the microwave magnetism of LFO films. [ABSTRACT FROM AUTHOR]

Polymorph engineering involves the manipulation of material properties through controlled structural modification and is a candidate technique for creating unique two-dimensional transition metal dichalcogenide (TMDC) nanodevices. Despite its promise, polymorph engineering of magnetic TMDC monolayers has not yet been demonstrated. Here we grow FeSe2 monolayers via molecular beam epitaxy and find that they have great promise for magnetic polymorph engineering. Using scanning tunneling microscopy (STM) and spectroscopy (STS), we find that FeSe2 monolayers predominantly display a 1T' structural polymorph at 5 K. Application of voltage pulses from an STM tip causes a local, reversible transition from the 1T' phase to the 1T phase. Density functional theory calculations suggest that this single-layer structural phase transition is accompanied by a magnetic transition from an antiferromagnetic to a ferromagnetic configuration. These results open new possibilities for creating functional magnetic devices with TMDC monolayers via polymorph engineering.

Intercalation has attracted considerable attention due to its extensive ability to modify the electronic, optical, and magnetic properties of two-dimensional (2D) layered nanomaterials. Typically, dispersed atoms or molecules are inserted into the van der Waals gap of the 2D materials. Recently, Guo et al. experimentally reported the novel VS2–VS superlattice, where the intercalation takes the form of atomic chain arrays. In this study, we employed the first-principles calculations based on density functional theory to investigate a series of analogous 2D MX2–MX–MX2 nanomaterials, which, consisting of 2D transition metal dichalcogenide bilayers, intercalated with a one-dimensional transition metal chalcogenide MX chain array, forming a hotdog-like structure. Some of the 2D MX2–MX–MX2 are thermally and dynamically stable, suggesting their potential for experimental fabrication similar to VS2–VS–VS2. MnS2–MnS–MnS2 and MnSe2–MnSe–MnSe2 have been found to exhibit ferromagnetic half-metallic properties. In addition, VSe2–VSe–VSe2, CrS2–CrS–CrS2, and CrSe2–CrSe–CrSe2 have been found to be thermally and dynamically stable. Under appropriate external stress, doping, or bias, they could become ferromagnetic half-metals, revealing their potential for spintronic applications. [ABSTRACT FROM AUTHOR]

In recent few years, the two-dimensional (2D) magnets have emerged as one of the most important frontiers in materials physics and attracted much attention. As one of the earliest experimentally discovered 2D magnets, CrI3 shows a wealth of properties and has been extensively studied. In particular, an intriguing characteristic of the CrI3 monolayer is its octahedrally coordinated hollow within the unit-cell, which enables the implantation of a magnetic atom, thereby resulting in an artificial 2D superlattice with fertile physics to explore. In this work, using first-principles calculations, we investigate the Co-implanted CrI3 monolayer, denoted as Co-(CrI3)2, and demonstrate the vital roles of the exchange channels of eg electrons in enhancing magnetism. It is shown that the Co-(CrI3)2 monolayer has a half-metallic ferrimagnetic (FiM) ground-state with a net in-plane magnetic moment of 5.0μB/f.u. and a relatively high Curie point (TC) of ∼195 K, noting that TC of pristine CrI3 is only 45–61 K. The FiM ordering is established by the strong anti-ferromagnetic coupling in the t2g-eg exchange channels of the nearest-neighbor (NN) Cr–Co pair and the sizeable ferromagnetic coupling of the third NN Cr–Cr pair mediated by the itinerant eg electrons. In addition, an in-plane biaxial tensile strain of ∼2% may further enhance TC up to ∼210 K. This work offers unique insights into the magnetism enhancement of the CrI3 monolayer by atom-implantation, paving the way for the development of 2D magnets. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dihalides (TMDHs) have attracted great interest owing to their unique magnetic and semiconductor properties. Compared with the mirror/inversion symmetric materials, 2D Janus materials possess vertical intrinsic dipole moment, which offer a versatile platform for the fundamental physics and future spintronic devices. Here, we systematically explore the magnetic and electronic properties of the 2D Janus transition metal dihalides MXY (M = Co and Ni; X ≠ Y = Cl, Br, and I) monolayers and bilayers by using density functional theory. The monolayer CoClBr, NiClBr, and NiBrI are bipolar ferromagnetic semiconductors that possess the valence and conduction band edges of different spin channels. The magnetism of the bilayer CoClBr, NiClBr, and NiBrI is highly dependent on the accumulated dipole moments of the two adjacent layers. When the dipole moments in both layers are aligned in the same direction and the accumulated dipole moments are nonzero, the systems are antiferromagnetic half semiconductors. However, when the dipole moments in the two layers are opposite and the accumulated dipole moments are zero, the systems are A-type antiferromagnetic semiconductors. Our findings are helpful to understand the magnetism of Janus TMDHs and guide experiments in exploring their potential application in spintronic devices. [ABSTRACT FROM AUTHOR]

The growth of two-dimensional van der Waals magnetic materials presents attractive opportunities for exploring new physical phenomena and valuable applications. Among these materials, Fe3GeTe2 (FGT) exhibits a variety of remarkable properties and has garnered significant attention. Herein, we have for the first time created a nanomesh structure—a honeycomb-like array of hexagonal nanopores—with the zigzag pore-edge atomic structure on thin FGT flakes with and without oxidation of the pore edges. It is revealed that the magnitude of ferromagnetism (FM) significantly increases in both samples compared with bulk flakes without nanomeshes. Critical temperature annealing results in the formation of zigzag pore edges and interpore zigzag-edge nanoribbons. We unveil that the non-oxide (O) termination of the Fe dangling bonds on these zigzag edges enhances FM behavior, while O-termination suppresses this FM by introducing antiferromagnetic behavior through edge O–Fe coupling. FGT nanomeshes hold promise for the creation of strong FM and their effective application in magnetic and spintronic systems. [ABSTRACT FROM AUTHOR]

Based on a β-diketonate ligand, a mononuclear Dy(III) complex, [Dy(dmpd)3(bpy)] (1) (dmpd = 4,4-dimethyl-1-phenylpentane-1,3-dione, bpy = 2,2′-dipyridyl), of [DyN2O6] type has been synthesized with a capping nitrogen-containing coligand. Then, a dual capping coligand 2,2′-bipyrimidine (bmp) is introduced to be a bridge to link two β-diketonate-Dy(III) motifs, leading to a new dinuclear Dy(III) complex, [Dy2(dmpd)6(bmp)] (2). Dy(III) centers in both complexes feature an N2O6 octacoordinated environment with an approximate square-antiprism geometry (D4d). Without a dc field, the SMM behaviour is absent in complex 1, but can be clearly observed in dinuclear 2 with a Ueff of 87.29 K. The significantly improved magnetism arising in 2 is mainly due to the modulation of the coordination environment around the Dy(III) ions and the superexchange magnetic interactions inside the dinuclear units, thus allowing for the effective inhibition of the quantum tunneling of magnetization at low temperatures and promotion of the uniaxial magnetic anisotropy. For 1, a diamagnetic Y(III) analogue [Y(dmpd)3(bpy)] (3) and diluted sample 1@Y were constructed to further perform the dilution experiment, coupled with theoretical calculations further supporting that the synergetic contributions of intermolecular dipole–dipole interactions, intramolecular coupling and uniaxial magnetic anisotropy cause the enhancement of dynamic magnetic relaxation. [ABSTRACT FROM AUTHOR]

Fe‐based mica minerals usually display two opposing magnetic ground states, either they behave as spin‐glasses or as layered ferrimagnets. No definite reason has been proposed as an explanation for this duality. This conundrum is unraveled by comparing the synthetic micas KFe3[MGe3]O10X2 with M═Fe and Ga, X═OH− and F−. Neutron diffraction demonstrates a 2D to 3D magnetic transition in KFe3[FeGe3]O10(OH)2 while just hints or no order at all are observed for the fluorides with M═Fe and Ga respectively. The 3D transition is triggered by the presence of iron in the intralayer tetrahedra. DFT+U calculations show that the magnetic exchange couplings between the previously believed solely magnetic octahedral layers would otherwise be frustrated without this intralayer iron. [ABSTRACT FROM AUTHOR]

In this study, we investigated the integration of an NdFeB N35 permanent magnet into an electromagnetic chuck to maintain its magnetic force continuously. By energizing or deenergizing the coil wrapped around the chuck, the surface magnetic force was increased or decreased, achieving either stronger adhesion or easy detachment of the attached object, respectively. ANSYS Maxwell software was utilized to simulate the initial model, the results of which were then compared with physical measurements. Keeping the external dimensions unchanged, the yoke's dimensions were used as the parameters to analyze the effect of changes in dimensions at different positions on the electromagnetic chuck's surface adhesion force. Differences between simulated and measured results for the initial model after energizing the electromagnetic chuck were within 6%. Among the simulations with different parameters, changes in the thickness of the outer frame base and inner diameter did not significantly affect the magnetic flux on the surface of the electromagnetic chuck. Therefore, these results were not shown in this study. Alterations in the yoke's dimensions affected the relative position and size of the coil or created new magnetic flux paths. A distance of less than 1 mm between the coil and the chuck surface significantly affected the surface magnetic flux density. [ABSTRACT FROM AUTHOR]

There have been increasing efforts to compute magnetic exchange coupling constants for transition metal complexes and magnetic insulators using the magnetic force theorem and Green's function-based linear response methods. These were originally conceived for magnetic metals, yet it has not been clear how these methods fare conceptually with the conventional models based on electron-correlation interactions among so-called magnetic orbitals. We present a spinor-based theoretical analysis pertinent to the magnetic force theorem and linear response theory using Brillouin–Wigner perturbation method and Green's function perturbation method, and we shed light on the conceptual nature of the Lichtenstein formula in its applications for calculations of the total energy and magnetic exchange coupling constants for both molecules and solids. Derivation of the magnetic force theorem in this perturbational analysis identifies the first-order energy correction terms, which are considered as the ferromagnetic component for the magnetic exchange interactions of transition metal compounds but are not included in the Lichtenstein formula. Detailed perturbational analysis of the energy components involved in the magnetic force theorem identifies the energy components that are missing in the Lichtenstein formula but are critical in the Anderson's model for transition metal complexes and magnetic insulators where magnetic orbitals can overlap. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of high-intensity running on the autonomic nervous system and sleep quality of male long-distance runners and to examine the impact of wearing magnetic garments on these parameters. Fifteen highly trained male collegiate long-distance runners participated in a randomized, double-blind crossover study. Participants completed two 30 km runs (30k-RUN) during a 10-day training camp. After each run, they wore either magnetic (MAG) or non-magnetic control (CTRL) garments. Sleep quality and heart rate variability (HRV) were assessed using a wrist-worn device before and after each 30k-RUN. Wearing MAG garments post-30k-RUN resulted in significantly longer deep sleep duration compared to CTRL. HRV analysis revealed that the MAG condition led to a significantly higher root mean square of successive RR interval differences and high-frequency power, indicating enhanced parasympathetic activity. The low-frequency to high-frequency ratio was significantly lower in MAG than in CTRL. Perceived recovery scores were significantly higher in MAG than in CTRL. The findings of this study suggest that wearing magnetic garments following high-intensity endurance running may promote parasympathetic dominance and improve sleep quality in male long-distance runners. These findings indicate that magnetic garments may be a practical method for enhancing recovery in athletes following intense training. [ABSTRACT FROM AUTHOR]

The global outbreak of pathogen diseases has brought a huge risk to human lives and social development. Rapid diagnosis is the key strategy to fight against pathogen diseases. Development of detection methods and discovery of related affinity reagents are important parts of pathogen diagnosis. Conventional detection methods and affinity reagents discovery have some problems including much reagent consumption and labor intensity. Magnetic-based microfluidic chip integrates the unique advantages of magnetism and microfluidic technology, improving a powerful tool for pathogen detection and their affinity reagent discovery. This review provides a summary about the summary of pathogen detection through magnetic-based microfluidic chip, which refers to the pathogen nucleic acid detection (including extraction, amplification and signal acquisition), pathogen proteins and antibodies detection. Meanwhile, affinity reagents are served as the critical tool to specially capture pathogens. New affinity reagents are discovered to further facilitate the pathogen diagnosis. Microfluidic technology has also emerged as a powerful tool for affinity reagents discovery. Thus, this review further introduced the selection progress of aptamer as next generation affinity through the magnetic-based microfluidic technology. Using this selection technology shows great potential to improve selection performance, including integration and highly efficient selection. Finally, an outlook is given on how this field will develop on the basis of ongoing pathogen challenges. [ABSTRACT FROM AUTHOR]

Objectives: Despite some existing studies on the safety of high static magnetic fields (SMFs), the effects of ultra-high SMFs above 20.0 T for embryonic development in early pregnancy are absent. The objective of this study is to evaluate the influence of 16.8–22.0 T SMF on the development of zebrafish embryos, which will provide important information for the future application of ultra-high field magnetic resonance imaging (MRI). Methods: Two-hour exposure to homogenous (0 T/m) 22.0 T SMF, or 16.8 T SMFs with 123.25 T/m spatial gradient of opposite magnetic force directions was examined in the embryonic development of 200 zebrafish. Their body length, heart rate, spontaneous tail-wagging movement, hatching and survival rate, photomotor response, and visual motor response (VMR) were analyzed. Results: Our results show that these ultra-high SMFs did not significantly affect the general development of zebrafish embryos, such as the body length or spontaneous tail-wagging movement. However, the hatching rate was reduced by the gradient SMFs (p < 0.05), but not the homogenous 22.0 T SMF. Moreover, although the zebrafish larva activities were differentially affected by these ultra-high SMFs (p < 0.05), the expression of several visual and neurodevelopmental genes (p < 0.05) was generally downregulated in the eyeball. Conclusions: Our findings suggest that exposure to ultra-high SMFs, especially the gradient SMFs, may have adverse effects on embryonic development, which should cause some attention to the future application of ultra-high field MRIs. Clinical relevance statement: As technology advances, it is conceivable that very strong magnetic fields may be adapted for use in medical imaging. Possible dangers associated with these higher Tesla fields need to be considered and evaluated prior to human use. Key Points: Ultra-High static magnetic field may affect early embryonic development. High strength gradient static magnetic field exposure impacted zebrafish embryonic development. The application of very strong magnetic fields for MR technologies needs to be carefully evaluated. [ABSTRACT FROM AUTHOR]

Purpose: The investigation has appraised the problem of an incompressible laminar steady magnetohydrodynamic (MHD) nanofluid stream over three distinct slendering thin isothermal needles of paraboloid, cylindrical and cone shapes. Water as a base liquid is assumed in this flow model. The influences of the Hall current and variable sorts of magnetic forces have enriched our investigation. Energy and concentration expressions consist of thermophoresis and Brownian migration phenomena. The analysis of thermal and mass slips of the presumed model has also been performed. Design/methodology/approach: A relevant transformation is implemented for the alteration of the leading partial differential equations (PDEs) to the equations with nonlinear ordinary form. Due to the strong nonlinearity of the foremost equations, the problem is solved numerically by embedding the well-known RK-4 shooting practice. The software MAPLE 2017 has been exploited in reckoning the entire computation. To enunciate the investigated upshots, some graphical diagrams have been regarded here. According to technological interest, we measured the engineering quantities like the Sherwood number, the coefficient of drag friction and the Nusselt number in tabular customs. Findings: The obtained consequences support that Hall current intensifies fluid movement when the needle is in a cone shape, while the superior velocity is noticed for cylindrical-shaped needles. The transference of heat responds inversely along with the growths of thermal and mass slip factors. Originality/value: No work has been performed on the flow model of radiated nanofluid over a variable-shaped thin needle under Hall current, the variable magnetic field and different slip factors. [ABSTRACT FROM AUTHOR]

In this paper, we present the Noether symmetries of locally rotationally symmetric Bianchi-type I (LRS BI), an anisotropic model, in the context of the teleparallel gravity. We study a certain modified teleparallel theory based on the action that, in particular, contains a coupling between the scalar field and field strength (magnetism part). We derive the symmetry generators and show that, by means of cyclic variables approach, one can not obtain a suitable solution for field equations. Hence by the use of beyond Noether symmetry (B.N.S.) approach, we solve the equations which carry Noether currents as well. By data analysis of the obtained results, compatible results with observational data at the last half of the age of universe which is accelerating are demonstrated. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of magnetohydrodynamics and heat transfer on the peristaltic transport of Prandtl fluid in a vertical endoscopic tube. The reduction of the complexity of the equations governing the flow of Prandtl fluid entails the use of long wavelength and low Reynolds number approximations. These complex equations for the pressure gradient and velocity profile are handled analytically using the perturbation technique with convective boundary conditions, and the temperature and concentration profiles are carefully solved for the exact solution. The frictional forces and pressure rise are also simulated with numerical integration. The resulting formulas for velocity, temperature, concentration, pressure rise, and pressure gradient are graphed using the MATLAB and MATHMATICA software, and the effects of all the different physical parameters are investigated and assessed. The streamlines with five distinct wave types are sketched at the conclusion to show the phenomenon of trapping. It is investigated that the velocity profile rises due to buoyancy forces and falls due to the influence of magnetic forces. [ABSTRACT FROM AUTHOR]

The structural, morphological, magnetic, and dielectric properties of lanthanum substituted nickel ferrite (NiLaxFe2−xO4) nanoparticles have been reported in this article. The amount of lanthanum substitution in NiLaxFe2−xO4 sample was varied from x = 0.025 to 0.125. The nanocrystalline Ni–La ferrites were synthesized using a solution combustion reaction (SCR) method. The orthorhombic crystal system of space group Pnma (62) is shown as the single-phase in all samples through structural investigation utilizing an X-ray diffraction (XRD) pattern. The observed trend indicates a positive correlation between the concentration of La and the corresponding rise in the predicted crystallite size values, which range from 60.5 nm to 65.2 nm. The nanoscale of the surface morphology has been confirmed by the utilisation of field emission scanning electron microscopy (FESEM). Energy dispersive X-ray (EDAX) mapping provides the compositional evidence for the prepared Ni–La ferrites. In addition, X-ray photoelectron spectroscopy (XPS) determines the ionic state of the individual atoms present in these samples. It reveals that there are no changes in the ionic state of the parent component atoms by substituting La. EDAX and XPS evidence the purity of prepared NiLaxFe2−xO4 samples without any other impurity elements. By regulating the composition of dopants, this research can substantiate the superparamagnetic characteristics of ferrites. The paramagnetic nature of lanthanum atoms involves in reducing the coercivity value. The dielectric measurement on NiLaxFe2−xO4 samples reveals that La3+ substitution effectively influence the electro-transport properties. [ABSTRACT FROM AUTHOR]

Introduction. This work was initiated by the problems of cardiovascular diseases, which are one of the main causes of mortality of the population of our planet. More than ten years ago, in 2012, approximately 3.7 million people died of acute coronary syndrome worldwide. The fight against such pathologies is carried out with the help of so-called stents, the manufacture of which can be carried out by the method of magnetic pulse «expansion» from hollow metal cylinders. The limited production possibilities of magnetic pulse «expansion» were caused by the minimum cross-sectional size of the inductor-instrument, which can be practically manufactured. Other tools are required to perform this operation. Novelty. A system of magnetic-pulse expansion of thin-walled pipes of small diameter with an inductor that excites an azimuthal electromagnetic field in the case of direct current passing through the processing object and in the absence of its connection in an electric circuit with an inductor is proposed. Purpose. The main analytical dependencies for the characteristics of the electromagnetic processes taking place in the inductor systems for the expansion of cylindrical conductive pipes of small diameter when direct passage of current through the processed object and when it is not connected to an electric circuit with an inductor (insulated billet) is derived. Methods. The solution of the boundary value problem with given boundary conditions was carried out by applying Laplace transforms and integrating Maxwell’s equations. Results. Analytical expressions were obtained for the main characteristics of the processes: the intensities of the excited electromagnetic fields and currents in the system depending on the parameters of the studied systems. The analysis of possible technical schemes for solving the given problem indicated the choice of the optimal variant of an effective system of magnetic-pulse «stretching» of thin-walled cylindrical conductors of small diameter. Practical value. Based on the qualitative analysis of the obtained results, recommendations for the practical implementation of the proposed system were formulated. The obtained dependences allow us to give numerical estimates of the effectiveness of excitation of magnetic pressure forces on the object of processing and to choose directions for further improvement of the magnetic pulse technology for solving such problems. [ABSTRACT FROM AUTHOR]

β-Gallium oxide has well-studied electrical characteristics but relatively less explored optical as well as magnetic properties. In this work, pure and Ni-doped β-Ga2O3 polycrystalline powders were prepared using a hydrothermal method to study the structural, optical, and magnetic properties at various concentrations of Ni at 1 M%, 3 M%, 5 M%, and 7 M%. XRD analysis confirmed the formation of monoclinic β-Ga2O3 up to Ni 1 M% doping. The formation of additional peaks was observed exclusively for the samples doped with Ni from 3 M% to 7 M%. These additional peaks belong to NiGa2O4 that has an inverse spinel structure. The reflectance studies using UV–Vis diffuse reflectance spectroscopy shows a reduction in bandgap from approximately 4.7 eV to 4.1 eV with the addition of the dopant. The emission peaks observed from photoluminescence studies shows UV, blue, and green emissions with varying intensity. Room-temperature magnetic studies performed using a vibrating sample magnetometer showed a transition from the diamagnetic state of the pure sample to the antiferromagnetic state with increasing Ni concentration in the doped samples. The diamagnetic properties of β-Ga2O3 makes it ineffective in spintronic applications. From the present work, the improved magnetism due to Ni doping coupled with the optical properties suggests that nickel-doped gallium oxide can be used as an optical magnetic bifunctional material. [ABSTRACT FROM AUTHOR]

We conducted a first-principles study on the electronic, magnetic, and optical characteristics of non-metallic atoms (B, C, F, H, N, O, P, S, and Si) doped in single-layer carbon germanium (GeC). The findings indicate that the introduction of various non-metallic atoms into the monolayer GeC leads to modifications in its band structure properties. Different non-metallic atoms doped in single-layer GeC will produce both magnetic and non-magnetic properties. B-, H-, N-, and P-doped GeC systems exhibit magnetic properties, while C-, F-, O-, S-, and Si-doped single-layer GeC systems exhibit non-magnetic properties. Different non-metallic-doped single-layer GeC systems will produce semiconductor, semimetallic, and metallic properties. The C-, N-, O-, P-, S-, and Si-doped GeC systems still exhibit semiconductor properties. The H-doped GeC system exhibits semimetallic properties, while the B- and F-doped GeC systems exhibit metallic properties. Other than that, the doping of B, H, N, and P atoms can modulate the magnetism of single-layer GeC. Subsequently, we studied the influence of the doping behavior on the work function, where the work function of the single-layer GeC system doped with P atoms is very small, indicating that its corresponding doping system (P-doped GeC system) can produce a good field emission effect. In the optical spectrum, the doped systems have a certain influence in the far ultraviolet region. Furthermore, our results showed that S- and Si-doped single-layer GeC systems are conducive to photocatalysis compared to the single-layer GeC system. [ABSTRACT FROM AUTHOR]

Based on the first‐principles calculation of density‐functional theory, the electronic structure and magnetic properties of hexagonal boron phosphide (h‐BP) with doping and applying strain to the transition‐metal (TM = Cr, Mn, Fe, Co, and Ni) elements are investigated. After the TM elements are introduced, the magnetism is induced. The magnetic moments are 3.00, 3.87, 1.00, 1.99, and 1.00 μB, respectively, which mainly contributed by the 3d orbitals of TM elements. In the case of magnetic coupling, Cr–Cr are mainly coupled antiferromagnetically at different distances. In addition, Fe–Fe performs a ferromagnetic state, and Co–Co represents an antiferromagnetic state with the distance of 3.213 Å. After applied strain, Co doped of the system shows the characteristics of semimetals under the application of 4% strain. It can be added that for h‐BP systems, doping Co and Mn increases its conductivity, which is beneficial to the study of spintronic materials. [ABSTRACT FROM AUTHOR]

In order to improve convective flow, this study primarily used techniques including curved surfaces and a strong magnetic force. Cold temperatures and even flow are experienced by both the circular outer wall and the sinusoidal inner wall. FHD can have a bigger effect when combined with iron oxide in the base fluid. The electric current-carrying wire was positioned close to the interior wall in order to produce Kelvin force. A novel modeling approach was chosen to ascertain the number of scalars throughout the entire domain, and the process was validated using earlier numerical work. Gravity forces, ferrofluid concentrations, and the Kelvin force serve as the main pillars of current research. Conduction features increase and the Nu rises by 12.44% when nanopowders are used. Due to gravity and magnetic forces, the nanofluid can move more easily through the container. At Ra = 1 e 3 and 1e4, respectively, Nu increases by 93.04% and 35.43%; with an increase in MnF. Additionally, Nu rises with Ra at Mn F = 0 and Mn F = 4 0 0 0 by 43.55% and 0.71%, respectively. [ABSTRACT FROM AUTHOR]

Electronic and magnetic properties of transition metal (TM) ion-doped monolayer zinc oxide (ML-ZnO) have been analyzed using ab-initio calculations in the frame work of density functional theory. Spin–spin interaction study reveals that Cr, Mn, Fe and Cu doped at Zn site of ML-ZnO show stable ferromagnetic ordering along with the half-metallic behavior for most of the cases. The electronic and magnetic properties of the pristine system can also be modified by using co-doping. 3d orbital electrons of the dopants are primarily responsible for the origin of magnetic moment and the remaining part comes from the 3d and 2p orbital electrons of Zn and O atoms, respectively. Moreover, the magnetic ordering in Fe-doped ML-ZnO can change with the doping distance between the dopants. [ABSTRACT FROM AUTHOR]

Spinel ferrites demonstrate extensive applications in different areas, like electrodes for electrochemical devices, gas sensors, catalysts, and magnetic adsorbents for environmentally important processes. However, defects in the real spinel structure can change the many physical and chemical properties of spinel ferrites. Although the number of defects in a crystal spinel lattice is small, their influence on the vast majority of physical properties could be really decisive. This review provides an overview of the structural characteristics of spinel compounds (e.g., CoFe2O4, NiFe2O4, ZnFe2O4, Fe3O4, γ–Fe2O3, Co3O4, Mn3O4, NiCo2O4, ZnCo2O4, Co2MnO4, etc.) and examines the influence of defects on their properties. Attention was paid to the classification (0D, 1D, 2D, and 3D defects), nomenclature, and the formation of point and surface defects in ferrites. An in-depth description of the defects responsible for the physicochemical properties and the methodologies employed for their determination are presented. DFT as the most common simulation approach is described in relation to modeling the point defects in spinel compounds. The significant influence of defect distribution on the magnetic interactions between cations, enhancing magnetic properties, is highlighted. The main defect-engineering strategies (direct synthesis and post-treatment) are described. An antistructural notation of active centers in spinel cobalt ferrite is presented. It is shown that the introduction of cations with different charges (e.g., Cu(I), Mn(II), Ce(III), or Ce(IV)) into the cobalt ferrite spinel matrix results in the formation of various point defects. The ability to predict the type of defects and their impact on material properties is the basis of defect engineering, which is currently an extremely promising direction in modern materials science. [ABSTRACT FROM AUTHOR]

By means of the first-principles method, the bias effect on the magnetism of polyacene (n-acene) connected to gold electrodes is investigated. A magnetic to nonmagnetic transition for the polyacene (n > 6) is observed when the bias exceeds a critical value. The mechanism is explored as the bias-induced variation of electronic localization, which leads to the exchange of dominant mechanism for molecular magnetism from Columbic interaction between electrons to electron hopping rate. A significant enhancement of the differential conductance and suppression of current spin polarization for the molecular device are also obtained accompanied by the transition of molecular magnetism. This work proposes a feasible way to manipulate the magnetism of polyacene via electric method and reveals the relation between molecular magnetism and its conductance. [ABSTRACT FROM AUTHOR]

The negative thermal expansion (NTE) materials, which can act as thermal‐expansion compensators to counteract the positive thermal expansion, have great applications merit in precision engineering. However, the exploration of NTE behavior with a wide temperature range has reached its upper ceiling through traditional doping strategies due to composition limitations. In this paper, the unique sluggish characteristics and extended optimization space in empirically screened high‐entropy anti‐perovskite (HEAP) are utilized to broaden the NTE temperature range. Typically, the NTE temperature range in Mn3Cu0.2Zn0.2Ga0.2Ge0.2Mn0.2N is broadened to ΔT = 235 K (5 K ≤ T ≤ 240 K), which is two or three times wider than that of traditional low‐entropy doping systems. The neutron diffraction analysis reveals a unique sluggish characteristic in magnetic phase transition which survives in an ultra‐wide temperature range of 5 K ≤ T ≤ 350 K (ΔT = 345 K). The sluggish characteristic is further experimentally proved to come from disturbed phase transition dynamics due to distortion in atomic spacing and chemical environmental fluctuation observed by the spherical aberration‐corrected electron microscope. The demonstration provides a unique paradigm for broadening the temperature range of NTE materials through entropy engineering. [ABSTRACT FROM AUTHOR]

Magnetic force is used to drive ferromagnetic objects by shortening the magnetic flux path to reduce magnetic reluctance and increase magnetic conductivity. Based on this characteristic, magnetic force drives have been widely applied in various fields, such as military, transportation, and engineering, attracting significant attention. This paper proposes a method for the nonchain transport of steel shell ammunition based on magnetic force. The force generated by the minimal magnetic resistance in the air gap is utilized to drive the steel shell ammunition. A calculation model for the driving component is proposed using the Maxwell stress tensor method, and the accuracy of the model is verified by simulating ammunition motion curves using finite element software. Finally, prototype experiments are conducted to explore the motion conditions under uncertain ammunition masses. The magnetic nonchain ammunition transport mechanism features a simpler structure and lower maintenance costs, making it more suitable for use on unmanned platforms. [ABSTRACT FROM AUTHOR]

While recent experiments confirm the existence of hundreds of topological electronic materials, only a few exhibit the coexistence of superconductivity (SC) and a topological electronic state. These compounds attract significant attention in forefront research because of the potential for the existence of topological SC, paving the way for future technological advancements. SrSn4 is known for exhibiting unusual SC below the transition temperature (TC) of 4.8 K. Recent theory predicts a topological electronic state in this compound, which is yet to be confirmed by experiments. Systematic and detailed studies of the magnetotransport properties of SrSn4 and its Fermi surface characterizations are also absent. For the first time, a quantum oscillation study reveals a nontrivial 흅‐Berry phase, very light effective mass, and high quantum mobility of charge carriers in SrSn4. Magnetotransport experiment unveils large linear transverse magnetoresistance (TMR) of more than 1200% at 5 K and 14 T. Angle‐dependent transport experiments detect anisotropic and fourfold symmetric TMR, with the maximum value (≈2000%) occurring when the angle between the magnetic field and the crystallographic b‐axis is 45°. The results suggest that SrSn4 is the first topological material with SC above the boiling point of helium that displays such high magnetoresistance. [ABSTRACT FROM AUTHOR]

We report the synthesis, structures and magnetic behaviour of two isostructural dinuclear Dy3+ complexes where the metal ions of a previously reported monomeric building block are connected by a peroxide (O22−) or a pair of fluoride (2×F−) bridges. The nature of the bridge determines the distance between the metal ion dipoles leading to a dipolar coupling in the peroxido bridged compound of only ca. 70 % of that in the bis‐fluorido bridged dimer. The sign of the overall coupling between the metals is antiferromagnetic for the peroxido bridged compound and ferromagnetic for the bis‐fluorido bridged complex. This in turn influences the magnetisation dynamics. We compare the relaxation characteristics of the dimers with those of the previously reported monomeric building block. The relaxation dynamics for the bis‐fluorido system are very fast. On the other hand, comparing the properties of the monomer, the peroxido bridged sample and the corresponding Y‐doped sample show that the relaxation properties via a Raman process have very similar parameters. We show that a second dysprosium is important for either tuning or detuning the Single Molecule Magnet (SMM) properties of a system. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates how thermal radiation, viscous dissipation, double-diffusive convection, and slip boundaries collectively affect the peristaltic movement of a magneto-pseudoplastic nanofluid within a uniform channel. The inclusion of slip boundary conditions at the channel walls helps to accurately represent the flow behavior of the nanofluid near these boundaries. The magneto-pseudoplastic nanofluid exhibits peculiar rheological features to flow dynamics due to pseudoplastic characteristics of nanoparticles in its composition and exposure to magnetic force. The mathematical formulation of motion equations is done through appropriate technique combining the properties of heat radiation, magnetic flux, double diffusion convection, and rheological features. The equation is further simplified by suitable method. The current study aims to evaluate the peristaltic movement under influence of slip boundaries characteristics, sort of concentration, heat radioactivity, flux properties, and temperature profile. Moreover, it will assess the flow dynamics with ratio of mass and heat exchange under the effect of critical parameters which include Prandtl number, Grashof number, slip limitations, and Hartmann number. So, the research will widen the theoretical underpinning of complex fluid transportation of magneto-pseudoplastic nanofluids under peristaltic flux and explicate the practical outcomes in terms of slip boundary settings in such systems. The results and conclusions are imperative for restructuring and devising biomedicine engineering, microfluidic equipment and gadgets, manufacturing techniques for complex fluid with peristaltic flow under the influence of slip limitations and magnetic force. [ABSTRACT FROM AUTHOR]

Miniaturization of medical tools promises to revolutionize surgery by reducing tissue trauma and accelerating recovery. Magnetic untethered devices, with their ability to access hard-to-reach areas without physical connections, emerge as potential candidates for such miniaturization. Despite the benefits, these miniature devices face challenges regarding force and torque outputs, restricting their ability to perform tasks requiring mechanical interactions such as tissue penetration and manipulation. To overcome magnetic actuation system-based force and torque limitations, this study proposes Variable Outer Radius Individually Addressable Coil Stacks (VORIACS), a novel magnetic actuation system optimized for high force output generation to magnetic devices within its workspace. The VORIACS marks significant improvements and breakthroughs in magnetic actuation within decimeter-scale workspace. The VORIACS is comprised of 12 coils that are optimized for 2D magnetic field generation under maximized power consumption of up to 12 kW. We implement six two-channel motor controllers, powered by six separate power supplies. Each of the twelve coils in the system is operated on its own motor-controller channel. This arrangement allows the system to exceed the magnetic forces and torques possible for single-coil versions of the same geometry. This study elaborates on optimizing, manufacturing, integrating, and demonstrating this system. Comparative analysis reveals that while a suboptimal, single-coil version of this system generates 0.31 N force (710 mT/m magnetic gradient magnitude), the VORIACS produces 1.673 N force (3834 mT/m magnetic gradient magnitude) on the same magnetic object placed 5 cm away from the coils. Moreover, the strong penetration force generated by VORIACS enables needle penetration to a mock gel that has the rigidity of liver tissue. In addition, we demonstrate the advantage of stacked coils with variable radii for magnetic field manipulability while maintaining the optimized force delivery property of the system, which improves control and could facilitate multi-tool manipulation. By enabling a fivefold increase in magnetic pulling force compared to its single-coil counterpart, VORICAS raises the potential penetration capabilities of untethered magnetic robotics in surgical procedures. [ABSTRACT FROM AUTHOR]

Pressure-preserved coring is an effective means to develop deep resources. However, due to the complexity of existing pressure-preserved technology, the average success rate of pressure-preserved coring is low. In response, a novel in situ magnetically controlled self-sealing pressure-preserved coring technology for deep reserves has been proposed and validated. This innovative technology distinguishes itself from conventional methods by employing noncontact forces to replace traditional pretensioning mechanisms, thereby enhancing the mechanical design of pressure-preserved coring equipment and significantly boosting the fault tolerance of the technology. Here, we report on the design, theoretical calculations, experimental validation, and industrial testing of this technology. Through theoretical and simulation calculations, the self-sealing composite magnetic field of the pressure controller was optimized. The initial pre-tensioning force of the optimal magnetic field was 13.05 N. The reliability of the magnetically controlled self-sealing pressure-preserved coring technology was verified using a self-developed self-sealing pressure performance testing platform, confirming the accuracy of the composite magnetic field calculation theory. Subsequently, a magnetically controlled self-triggering pressure-preserved coring device was designed. Field pressure-preserved coring was then conducted, preliminarily verifying the technology's effective self-sealing performance in industrial applications. Furthermore, the technology was analyzed and verified to be adaptable to complex reservoir environments with pressures up to 30 MPa, temperatures up to 80 ℃, and pH values ranging from 1 to 14. These research results provide technical support for multidirectional pressure-preserved coring, thus paving a new technical route for deep energy exploration through coring. [ABSTRACT FROM AUTHOR]

The primary aim of this study is to investigate the degradation efficacy of the Ppy/TiO2-Fe photocatalyst for MB dye in an aqueous solution. Firstly, the direct addition of TiO2 and Fe was done to prepare Ppy/TiO2-Fe photocatalyst. Fourier transformation infrared spectroscopy, XRD, SEM, BET surface area analysis, and magnetization tests established the formation of the Ppy/TiO2-Fe photocatalyst. The crystallite sizes of TiO2, Fe-TiO2, and Ppy/TiO2-Fe photocatalyst were estimated to be 24.99 nm, 21.94 nm, and 21.84 nm, respectively. For the synthesis confirmation, the FTIR spectrum confirmed the existence of Ti-O, Fe-O, and Ppy-related bonds. While comparing the SEM images, the impact of polypyrrole on the particle shape was observed with less aggregation and increased surface roughness. The VSM analysis revealed that incorporating polypyrrole (Ppy) into Fe-TiO2 significantly enhances its magnetic properties, with Ppy/TiO2-Fe exhibiting superparamagnetic behavior, characterized by a higher saturation magnetization (Ms) of 33.11 emu/g and a lower coercivity (Hc) of 0.160 Oe, compared to Fe-TiO2's Ms of 1.09 emu/g and Hc of 341.39 Oe. The N2 sorption desorption, with a specific surface area of 2.25 × 102 m2/g, is beneficial for photocatalytic activity. The concentration of dye, amount of catalyst, pH, and temperature were studied to evaluate the photocatalytic efficiency of the synthesized Ppy/TiO2-Fe photocatalyst under different conditions. The findings revealed a degradation efficiency of 91.92%. The degradation rate reached 91.92% under optimal conditions within 120 min and could be fitted well by first-order kinetics. The photocatalytic efficiency was also evaluated for the scavenger, and the concentration of H2O2 and the reusability of the catalyst were demonstrated. Based on the observed results, the Ppy/TiO2-Fe photocatalyst could be applied more effectively and efficiently to photocatalytic degradation of organic dyes in wastewater treatment. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study investigates the development of 3D chitosan-x-cobalt ferrite scaffolds (x = 5, 7.5, and 10 wt%) with interconnected porosity for potential biomedical applications. The objective was to evaluate the effects of magnetic particle incorporation on the scaffolds' structural, mechanical, magnetic, and biological properties, specifically focusing on their biocompatibility and antimicrobial performance. Methods: Scaffolds were synthesized using freeze-drying, while cobalt ferrite nanoparticles were produced via a pilot-scale combustion reaction. The scaffolds were characterized for their physical and chemical properties, including porosity, swelling, and mechanical strength. Hydrophilicity was assessed through contact angle measurements. Antimicrobial efficacy was evaluated using time kill kinetics and agar diffusion assays, and biocompatibility was confirmed through cytotoxicity tests. Results: The incorporation of cobalt ferrite increased magnetic responsiveness, altered porosity profiles, and influenced swelling, biodegradation, and compressive strength, with a maximum value of 87 kPa at 7.5 wt% ferrite content. The scaffolds maintained non-toxicity and demonstrated bactericidal activity. The optimal concentration for achieving a balance between structural integrity and biological performance was found at 7.5 wt% cobalt ferrite. Conclusions: These findings suggest that magnetic chitosan-cobalt ferrite scaffolds possess significant potential for use in biomedical applications, including tissue regeneration and advanced healing therapies. The incorporation of magnetic properties enhances both the structural and biological functionalities, presenting promising opportunities for innovative therapeutic approaches in reconstructive procedures. [ABSTRACT FROM AUTHOR]

The large dimensions of the 1000 MW hydroelectric generator sets require high mounting accuracy. Small deviations can lead to asymmetry, which in turn triggers unbalanced magnetic pulls and moments. Therefore, symmetry is a central challenge in the installation and operation of giant hydroelectric generators. In this paper, the effects of radial eccentricity, axial offset, and rotor shaft deflection on the unbalanced magnetic pull and moment are investigated by transient finite element analysis of the asymmetric magnetic field. The results of the time-domain and frequency-domain analyses show that asymmetric operation generates unbalanced magnetic forces and moments. These forces and moments increase linearly with increasing offset or deflection rate. When the eccentricity meets the installation criteria, the unbalanced magnetic pull forces are small and within acceptable limits. This study helps to understand the relationship between asymmetry and unbalanced magnetic pulling forces in large hydroelectric generators, and provides a theoretical basis for standardizing installation deviation control. [ABSTRACT FROM AUTHOR]

We have successfully fabricated a series of the SmCaBCuO bulk superconducting ceramics with different ratios of nanoscale Boron doping into mixture powder by the solid-state reaction method. Permanent magnets (PMs) with three different values in the same form were used for magnetic levitation force (MLF) measurements. During measurement of levitation forces between small PMs and bulk high Tc superconducting ceramic materials, significant hysteretic behavior was observed as a function of the distance between the magnet and the superconductor. We focused on the effect of doping and different permanent magnets on magnetic levitation force (MLF) measurements and magnetic stiffness calculations of materials, considering zero field-cooling (ZFC) and field-cooling (FC) conditions. It was seen that MLF decreased with the increase in boron dopant in the sample under ZFC conditions. We explained this result with weak bonds between grain boundaries, cracks and grain size reduction in the samples. Under FC conditions, with the increase of permanent magnet value and nano boron doping, the levitation force, which should be effective, left its place to the attractive force. Flux trapping centers formed by doping dominate the attractive force. The increase in doping caused a decrease in magnetic stiffness values. The increase in the permanent magnet caused an increase in the stiffness values of the material. This result agrees with the literature. The MLF and magnetic stiffness data got will be useful in the technological applications of maglev and carrier systems. [ABSTRACT FROM AUTHOR]

Ultralow temperature crystals of the helium isotopes 3 He and 4 He are intriguing quantum systems. Deciphering the complex features of these unusual materials has been made possible in large part by Alexander Andreev's groundbreaking research. In 1978, Andreev and Alexander Parshin predicted the existence of melting/freezing waves at the surface of a solid 4 He crystal, which was subsequently promptly detected. Successively, for the fermionic 3 He superfluid/solid interface, even more intricate crystallization waves were anticipated, although they have not been observed experimentally so far. In this work, we provide preliminary results on 3 He crystals at the temperature T = 0.41 mK, supporting the existence of spin supercurrents in the melting/freezing waves on the crystal surface below the antiferromagnetic ordering temperature T N = 0.93 mK, as predicted by Andreev. The spin currents that accompany such a melting-freezing wave make it a unique object, in which the inertial mass is distinctly different from the gravitational mass. [ABSTRACT FROM AUTHOR]

The synthesis of a novel complex [Ni3 (L3 -)2 (1,4-bib)4 (H2 O)2]·5H2 O (1) with three-dimensional framework structure was achieved through a hydrothermal reaction, employing 5-((4-carboxylphenoxy)-methyl) isophthalic acid (H3 L) as the main oxygen-containing ligand, complemented by the N-donor ligand 1,4-bis(1H-imidazol-1-yl)benzene (1,4-bib), and Ni(II) ions. The structure of complex 1 was characterized by single crystal X-ray diffraction, powder X-ray diffraction, and elemental analysis. Complex 1 is crystallized in the triclinic crystal system of P-1 space group, and its crystallographic parameters are a =1. 260 5(7) nm, b = 1. 349 1(7) nm, c = 1. 364 8(7) nm, α = 111. 913(8)°, β = 117. 251(7)°, γ =90. 732(8)°, V =1. 866 2(18) nm3, Z =1, Mr =1 769. 66, F(000) =916, μ = 0. 84 mm-1, Dc = 1. 575 mg·m-3, S =1. 06, R1 =0. 056, wR2 =0. 159. The joint contribution of semi-rigid tricarboxylic acid ligand L3 -, rigid 1,4-bib and also with Ni(II) ion to form a predictable high-dimensional structure. Complex 1 is a three-dimensional network constructed through the coordination of N and O atoms with Ni ion and the structural extension of the ligand. In addition, the magnetic properties of Ni(II) compound containing single d electron center were studied: the carboxyl group in mononuclear complex 1 only binds to one cation, resulting in magnetism in the solid being determined by the behavior of single metal ions. Variable temperature magnetic susceptibility of　χmT in complex 1 can be described by zero field splitting. [ABSTRACT FROM AUTHOR]

Y1-xNdxFe1-yNiyO3 (x = 0, y = 0; x = 0.05, y = 0.05; x = 0.05, y = 0.10; x = 0.05, y = 0.15) powders with different concentrations of Nd3+ and Ni2+ doped ions were synthesized by sol-gel method. The structure, morphology, and magnetic properties of the materials were characterized by powder X-ray diffraction (XRD), scanning electron microscope (SEM), and physical property measurement system (PPMS). X-Ray diffraction results show that all the prepared samples are in the single perovskite phase without any secondary phases. The measured doping content was basically consistent with the initial designed content. The remanent magnetization (Mr) and saturation magnetization (Ms) of the synthesized YFeO3 were 0.701 emu/g and 1.481 emu/g, respectively, and the coercivity (Hc) reached 19,000 Oe. The results also showed that the Mr and Ms values of YFeO3 increase, while the Hc values decrease with increasing Ni2+ ion content. When the doping concentrations are x = 0.05 and y = 0.15, the values of Mr and Ms are 0.787 emu/g and 1.782 emu/g, respectively, with Hc at 2100 Oe. From the research results, it can be observed that the introduction of doped ions enhances the super-exchange interactions. [ABSTRACT FROM AUTHOR]

JANA2020 is a program developed for the solution and refinement of regular, twinned, modulated, and composite crystal structures. In addition, JANA2020 also includes a magnetic option for solving magnetic structures from powder and single‐crystal neutron diffraction data. This tool uses magnetic space and superspace symmetry to describe commensurate and incommensurate magnetic structures. The basics of the underlying formulation of magnetic structure factors and the use of magnetic symmetry for handling modulated and non‐modulated magnetic structures are presented here, together with the general features of the magnetic tool. Examples of structures solved in the magnetic option of JANA2020 are given to illustrate the operation and capabilities of the program. [ABSTRACT FROM AUTHOR]

The magnetic structure adopted by a material relies on symmetry, the hierarchy of exchange interactions between magnetic ions and local anisotropy. A direct pathway to control the magnetic interactions is to enforce dimensionality within the material, from zero‐dimensional isolated magnetic ions, one‐dimensional (1D) spin‐chains, two‐dimensional (2D) layers to three‐dimensional (3D) order. Being able to design a material with a specific dimensionality for the phenomena of interest is non‐trivial. While many advances have been made in the area of inorganic magnetic materials, organic compounds offer distinct and potentially more fertile ground for material design. In particular magnetic metal–organic frameworks (mMOFs) combine magnetism with non‐magnetic property functionality on the organic linkers within the structural framework, which can further be tuned with mild perturbations of pressure and field to induce phase transitions. Here, it is examined how neutron scattering measurements on mMOFs can be used to directly determine the magnetic structure when the magnetic ions are in a 2D layered environment within the wider 3D crystalline framework. The hydrated formate, in deuterated form, Co(DCOO)2·2D2O, which was one of the first magnetic MOFs to be investigated with neutron diffraction, is reinvestigated as an exemplar case. [ABSTRACT FROM AUTHOR]

Topological analysis is widely adopted in various research fields to unveil intricate features and structural relationships implied in geometrical objects. Especially, in the fields of data analysis, exploring the topological properties of various images offers rich insights into the intrinsic geometrical information within them. In this study, a novel approach is proposed to investigate the topological properties of arbitrary grayscale images by employing a straightforward procedure used in 2D magnetism studies to calculate topological numbers. This method utilizes machine learning techniques to transfer chiral magnetic textures onto the images. Then, the topological number is then computed directly from the converted images by integrating the solid angles formed by adjacent spin vectors. The method successfully identifies the topological numbers of various grayscale images, showing stable performances against small noises. Furthermore, two applications of the method: are demonstrated topological analysis of the Modified National Institute of Standards and Technology (MNIST) dataset and the counting of blood cells in microscopic images. [ABSTRACT FROM AUTHOR]

Recent experimental and theoretical work has focused on two-dimensional van der Waals (2D vdW) magnets due to their potential applications in sensing and spintronics devises. In measurements of these emerging materials, conventional magnetometry often encounters challenges in characterizing the magnetic properties of small-sized vdW materials, especially for antiferromagnets with nearly compensated magnetic moments. Here, we investigate the magnetism of 2D antiferromagnet CrPS4 with a thickness of 8 nm by using dynamic cantilever magnetometry (DCM). Through a combination of DCM experiment and the calculation based on a Stoner–Wohlfarth-type model, we unravel the magnetization states in 2D CrPS4 antiferromagnet. In the case of H ∥ c, a two-stage phase transition is observed. For H ⊥ c, a hump in the effective magnetic restoring force is noted, which implies the presence of spin reorientation as temperature increases. These results demonstrate the benefits of DCM for studying magnetism of 2D magnets. [ABSTRACT FROM AUTHOR]

Magneto‐ionics, as the electrochemical reconfiguration of magnetic materials at low gating voltages, is a highly energy‐efficient alternative to control magnetism. For the fastest magneto‐ionic concept based on hydrogen, fundamental mechanisms are currently under debate, mainly because quantitative compositional information inside the magnetic materials upon gating is lacking. Using the electrochemical hydrogen loading of Co/Pd multilayers with perpendicular anisotropy, this study demonstrates that the hydrogen concentration inside the magnetic material determines its magnetic properties. Hydrogen concentrations up to a maximum of (0.24 ± 0.01) hydrogen atoms per metal atom can be set deterministically by voltage and are quantified via flow‐cell coulometry. With increasing hydrogen concentration, a continuous increase in coercivity of up to 15% and a decrease in magnetic domain‐wall velocity by an order of magnitude are observed using in situ MOKE microscopy. This enables the voltage‐controlled stop‐and‐go of domain walls. These magneto‐ionic effects can be explained by an increasing perpendicular anisotropy with increasing hydrogen content in Co/Pd multilayers, which is supported by theory. Importantly, the approach should be transferable to other ionic systems, such as lithium‐ or oxygen‐based ones, where it can uncover the yet hidden effects of ionic concentration on the magnetic properties and guide the design of functional magneto‐ionic devices. [ABSTRACT FROM AUTHOR]

2D van der Waals antiferromagnets have emerged as excellent candidates for studying novel low‐dimensional magnetism. The recently discovered spin–orbit‐entangled excitonic bound state appearing below the Néel temperature of 150 K in 2D antiferromagnetic NiPS3 (the so‐called Zhang–Rice (ZR) exciton) has drawn considerable attention in terms of exploring the strong correlation of spins, orbitals, and charges in a localized many‐body state. However, the formation mechanism of ZR excitons remains unclear, and its ultrafast dynamics have yet to be fully explored. Here, utilizing broadband transient reflectivity spectroscopy, the strong correlation between the charge‐transfer state excitation and the dynamic evolution of ZR excitons is investigated. Through systematic tuning of the pumping photon energy across the charge‐transfer state in NiPS3, the results reveal a short radiative lifetime of tens of picoseconds and a long nonradiative lifetime of up to nanoseconds for ZR excitons following an ultrafast charge transfer of ≈2 ps from the charge‐transfer state. The findings provide evidence of charge‐transfer‐induced ZR excitonic states in NiPS3, where the intriguing phenomena of strongly coupled spins and charges can be explored. [ABSTRACT FROM AUTHOR]

Secondary flow path is one of the crucial aspects during the design of centrifugal blood pumps. Small clearance size increases stress level and blood damage, while large clearance size can improve blood washout and reduce stress level. Nonetheless, large clearance also leads to strong secondary flows, causing further blood damage. Maglev blood pumps rely on magnetic force to achieve rotor suspension and allow more design freedom of clearance size. This study aims to characterize turbulent flow field and secondary flow as well as its effects on the primary flow and pump performance, in two representative commercial maglev blood pumps of CH-VAD and HeartMate III, which feature distinct designs of secondary flow path. The narrow and long secondary flow path of CH-VAD resulted in low secondary flow rates and low disturbance to the primary flow. The flow loss and blood damage potential of the CH-VAD mainly occurred at the secondary flow path, as well as the blade clearances. By contrast, the wide clearances in HeartMate III induced significant disturbance to the primary flow, resulting in large incidence angle, strong secondary flows and high flow loss. At higher flow rates, the incidence angle was even larger, causing larger separation, leading to a significant decrease of efficiency and steeper performance curve compared with CH-VAD. This study shows that maglev bearings do not guarantee good blood compatibility, and more attention should be paid to the influence of secondary flows on pump performance when designing centrifugal blood pumps. [ABSTRACT FROM AUTHOR]

The current study looks at the peristaltically driven motion of Carreau fluid in a symmetric channel under the influence of an induced and applied magnetic field. Tantalum (Ta) and Gold (Au) nanoparticles (NPs) with thermal radiation effects are incorporated in the hybrid nanofluid. The proposed mathematical modeling in two dimensions is finalized by employing lubrication theory. The finalized forms of mathematical modeling are nonlinear, and a perturbation approach is used to solve them. Up to the second-order approximation, solutions for velocity distribution, induction equation, and temperature distribution are reported. For velocity, current density, magnetic force function, induced magnetic field, and temperature profile, graphical and numerical results are presented. For simple and hybrid nanofluids, shear-thinning, Newtonian, and shear-thickening scenarios, numerical data are also presented. The current study aims to be useful in the medical field since Ta-NPs with low cytotoxicity can remove unwanted reactive oxygen species, providing protection for biomedical applications. Magnetic drug targeting is an effective and accurate way for drug delivery to the affected areas in biomedical science. It is accomplished by binding the medicine to biologically suitable magnetic nanoparticles, which are then steered towards the target by carefully placing magnets on the body's external surface. [ABSTRACT FROM AUTHOR]

Miniature scroll compressors (MSCs) are recognized for their superior characteristics—compact design, silent operation and energy-saving performance. One of its main challenges is to maintain dynamic sealing between the fixed and orbiting scrolls during the operation. This paper adopts a passive magnet mechanism (PMM) to balance the axial gas force in MSCs. The PMM with an integral magnet configuration (IMC) is investigated first, and the dimensions of the magnet and fixed ring are found as the paramount factors to determine the magnitude of axial magnetic force. However, the IMC is unable to follow the unsteady characteristics of the target axial gas force, so the scrolls will experience a large period of over-sealing during its operation. To overcome this limitation, an innovative modular magnet configuration (MMC) is proposed and investigated. The height of each magnet segment is treated as individual design variable, and genetic algorithm optimization is carried out to seek for the best force balance performance according to two indices—maximum force difference (MFD) and integral-average force difference (IAFD). With precise design of each magnet segment, the MMC is able to provide unsteady magnetic force and thus better balance performance. Compared with the IMC, the improvements are up to 52 % reduction of MFD and 66 % reduction of IAFD. The derived superior MMC designs reveal a common characteristic that the "N" and "E" magnets have short segments at their outer fringe and the "S" and "W" magnets have short segments at their inner fringe. The axial magnetic force characteristics of the IMC and MMC are validated by prototype experiments. [ABSTRACT FROM AUTHOR]

In ternary nitrides, the Ga0.9Fe3.1N sample has ultimately been prepared through solid‐gas preparation for the gallium‐richest phase GaFe3N. The substitution of gallium atoms for iron atoms weakens the saturation magnetization of ferromagnetic γʹ‐Fe4N and induces the transmission from ferromagnetism to antiferromagnetism. A new magnetic behavior, defined as the spin glassy magnetic state, has been observed in the temperature‐dependent magnetic performance measurement process for Ga0.9Fe3.1N. The magnetic competition between ferromagnetic and antiferromagnetic Fe–Fe bonds will lead to the spin frustration of the magnetic system. And even the positional disorders caused by substitution, will all be responsible for the spin glassy behavior in Ga0.9Fe3.1N. [ABSTRACT FROM AUTHOR]

Solid cancer remains a serious threat to global health despite decades of progress. Traditional chemotherapy treatment has been used to curb the disease despite its inability to reach cancer cells at high enough quantities leading to adverse toxicity on healthy cells, producing severe side effects, and exacerbating patient suffering. Active targeted nano-drugs (ATNDs) acting as transporter systems have become a viable solution to this shortcoming, offering the possibility of more precise cancer targeting. Therefore, in the present study, we develop a numerical model of capturing ATNDs, incorporating movements within and outside the tumor spheroid and the magnetic forces guiding the nanoparticles. By combining a model of ATNDs transport with a tumor-effector dynamic model based on porous media phenomena, we demonstrate how the models may be combined to model drug-loaded nanoparticle transport in an external magnetic field. We analyze the controlled drug delivery against traditional chemotherapy based on the combined effect of immunotherapy and chemotherapy with the dispersion of nano-drugs to lead a solute cloud toward the tumor. We found that the amalgamation of immune and chemotherapy delivered by ATNDs enhances cancer therapy efficacy compared with conventional chemotherapy. Increased drug convection toward the tumor region presented by ascending values of the Peclet number inhibits the growth of tumor cells and prolongs progression-free survival. Increases in source term and vessel permeability also increase the likelihood of tumor suppression, while raising the hematocrit and magnetic number results in reduced tumor cell killing. Sensitivity analysis of the dynamic model parameters has been discussed. This work demonstrates that ATND-delivery systems can improve therapeutic agent delivery to the tumor tissue, and promote tumor cell killing. • Analyze the impact of drug dispersion on the dynamical systems of tumor-effectors with conventional and targeted therapy. • Incorporate drug dispersion phenomena to describing targeted nano-drugs delivery with hematocrit and drug source term. • Numerical and sensitivity simulation shows the impact of the flow and dynamical control parameters on therapy treatment. • Targeted nano-drug delivery shows more prominent in drug accumulation in the tumor than the conventional treatment. • Outcomes demonstrate the effectiveness of targeted drug delivery to the tumor tissue and enhance tumor cell kill. [ABSTRACT FROM AUTHOR]