Abstract The Bi square net, a structural motif in a diverse array of layered compounds, has emerged as a desirable system for investigating the interplay of strong spin-orbit coupling, reduced dimensionality, and magnetism. We present a comprehensive study of Y 2 O 2 Bi single crystals, using high-resolution angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) calculations to elucidate the intrinsic electronic structure of the Bi square net. Our findings reveal a pronounced two-dimensional character of the electronic states, with the Bi square net dominating the low-energy electronic structure. While Y 2 O 2 Bi itself exhibits no topological features, our DFT calculations on related Bi square net compounds reveal that the surrounding crystal environment can induce non-trivial topology, as exemplified by the topological insulator LiBi. This comparative study establishes a crucial benchmark for understanding Bi square net physics and informs the design of future Bi square net-based quantum materials.

Abstract Paleomagnetic and rock magnetic analyses were conducted on sediment cores from the northeastern Greenland Shelf and Young Sound along the western edge of Fram Strait. The paleomagnetic signal in all three sediment cores is characterized by a strong and stable single component magnetization carried by low coercivity ferrimagnetic single domain or vortex state grains, attesting to the quality of the recorded relative paleointensity (RPI) and paleomagnetic secular variation (PSV) signals. Comparison with other archives from the northern North Atlantic, northern Greenland, and northern Europe and with geomagnetic field model outputs indicates broad similarities between the records, particularly with Finnish, Swedish and southern Greenland records. Comparison of the new RPI records with global geomagnetic field models and cosmogenic isotope production rates highlights the global character of the geomagnetic variations from the northeastern Greenland Shelf. Virtual geomagnetic pole (VGP) paths for the last 8 kyr compared to geomagnetic field strength maps at the core‐mantle boundary over the same time interval illustrate that, at times of high intensity, geomagnetic flux lobes could have an effect on VGP migration. We suggest that High Arctic PSV is most likely driven by millennial‐scale hemispheric geomagnetic flux lobe geometry changes.

Abstract BACKGROUND Efficient removal of atrazine (ATZ) from water is crucial but remains challenging. This study aimed to develop a novel iron‐modified biochar from corn cob for ATZ adsorption. RESULT Iron‐modified corn cob biochar was fabricated via a facile one‐step pyrolysis method under nitrogen atmosphere, and systematically characterized using various techniques. The optimal sample (BCA700) exhibited a specific surface area of 411.6 m 2 g −1 , high crystallinity, rich functional groups and strong magnetism. Adsorption experiments showed that 10 mg of BCA700 could remove >94% of ATZ (100 mL, 5 mg L −1 ) at room temperature within 1 h, with a saturated adsorption capacity of 47.10 mg g −1 . The adsorption process was well fitted to the pseudo‐second‐order kinetic model and Freundlich isotherm model, and thermodynamic parameters (Δ G < 0, Δ H = 73.32 kJ mol −1 ) confirmed it was a spontaneous and endothermic process. The adsorption mechanism was attributed to π – π conjugation and electrostatic attraction. BCA700 showed high adaptability to initial pH (3–11), reaction temperature (15–35 °C) and organic pollutant type, and retained >80% ATZ removal rate after three adsorption–desorption cycles. CONCLUSION This work provides a novel approach for corn cob resource utilization and an efficient adsorbent for pesticide‐contaminated wastewater treatment. © 2026 Society of Chemical Industry (SCI).

Magnets are essential for mobile consumer electronics, electric motors that power industry and the future of transportation as well as generating and transforming most electric power. Strong magnets reduce the size and weight of motors and generators as well as improve efficiency. The most powerful -based magnets have a complex structure like millions that are expected to exist but have not been made and characterized. With the recent developments of AI materials discovery techniques, which enable data-driven and machine-learning-assisted screening, together with computational approaches that can accurately predict intrinsic magnetic properties of a given structure, and high-throughput autonomous labs, the discovery of new, ultra-powerful magnet materials with saturation magnetization greater than 2.5 Tesla or magnetic energy density ( ) greater than 800 kJ/ is now quitepossible.

A natural-biopolymer sodium alginate magnetic multifunctional adsorbent with high capacity for broad-spectrum fluoroquinolone antibiotic removal from water.

Poor intratumoral penetration remains a major obstacle to effective chemotherapy, caused by dense extracellular matrices, high interstitial pressure, and abnormal vasculature. Magnetic nanoparticle (NP)-mediated drug delivery provides spatial control, but existing systems suffer from low drug loading, weak responsiveness to tumour microenvironments, and limited penetration. Here, we report for the first time a self-assembled nanoplatform in which ultrasmall Fe₃O₄ NPs are evenly distributed within a carrier-free doxorubicin (DOX) core and surface-modified with glycol chitosan (Fe₃O₄-DOX@GC NPs). This unique architecture simultaneously achieves ultra-high drug loading (69%) and markedly enhances responsiveness to external magnetic fields, addressing two long-standing challenges in magnetic nanomedicine. In addition, tumour acidity triggers surface charge reversal from negative to positive, promoting efficient cellular uptake. In 3D tumour spheroids, dual static and alternating magnetic fields increased DOX retention by 2.02-fold compared with static fields alone. In vivo, magnetic guidance produced a 6.3-fold increase in tumour accumulation and a 55% tumour volume reduction relative to free DOX. Importantly, the nanoplatform also activated antitumour immunity, significantly expanding cytotoxic T cells and antitumoral macrophages. This first-in-class dual chemotherapeutic–immunotherapeutic nanoplatform establishes a powerful strategy to overcome tumour penetration barriers while reshaping the immune microenvironment for improved cancer therapy. • First demonstration of uniformly distributed magnetic cores in carrier-free drug NPs • 6853 Fe₃O₄ NPs uniformly embedded in each DOX NP for strong magnetism • Nanomedicine combines high loading, magnetic control & deep tumour penetration. • Magnetic guidance enhances tumour DOX delivery 6.3-fold over free DOX in vivo. • Fe₃O₄-DOX@GC NPs synergise chemotherapy with immunotherapy in vivo.

Abstract A population of anomalous ultramassive white dwarfs discovered with Gaia, often referred to as the Q branch, show high (multi-Gyr) cooling delays produced by exotic physical mechanisms. They are believed to be the products of stellar mergers, but the exact origin and formation channel remain unclear. We obtained a spectroscopically complete, volume-limited sample of the Q branch region within 100 pc and found significant differences in atmospheric composition and rotation rates as a function of tangential velocity. In particular, we discover that stellar remnants with the longest cooling delays do not show strong magnetism nor detectable short-period rotational variability, as opposed to what is generally believed for double-degenerate mergers. This indicates that either these white dwarfs arise from a formation channel with no strong magnetism induced, or that the magnetism produced from the merger dissipates over the cooling delay timescales. Our follow-up photometry has also discovered pulsations in the second and third hydrogen-dominated DAQ white dwarfs, one hotter than 15,500 K, possibly extending the boundaries of the DAV instability strip for white dwarfs with thin hydrogen layers.

Multifunctional magneto-theranostic nanoplatform, with integrate imaging and therapy in simple platform offer transformative potential for precision cancer management due to their strong magnetic properties, biocompatibility, and versatile theranostic capabilities. Here, we report for the first time the theranostic application of in situ mesoporous core-shell MIL-88A@CuFe2O4 nanohybrid, as an interesting smart platform for dual-mode T1-T2MRI and optical imaging with quantitative analysis, combined with pH-sensitive targeted drug delivery. The nanohybrid was fabricated via a simple in situ synthesis, where Fe (0) from the CuFe2O4 core serves as a Fe3+ source for MIL-88A shell crystallization in the presence of fumaric acid, producing a mesoporous structure with high porosity and strong magnetism. Fe3+ centers in the MIL-88A shell provide T1 contrast, while the CuFe2O4 core enhances both T1 and T2 signals, achieving robust dual-mode MRI (r1 = 73.0 mM-1 s-1, r2 = 700.9 mM-1 s-1). The mesoporous shell allows pH-sensitive controlled release of doxorubicin, and folate conjugation ensures active tumor targeting, while intrinsic doxorubicin fluorescence enables optical tracking of biodistribution in vivo. Comprehensive in vitro and in vivo evaluations demonstrated high biocompatibility, selective cancer cell uptake, effective pH-responsive drug release, dual-modal MRI and fluorescence contrast, and significant tumor growth inhibition in a triple-negative breast cancer (4T1) mouse model. The nanohybrid's combination of high porosity, strong magnetism, dual T1-T2MRI contrast, targeted drug delivery, and therapeutic efficacy distinguish it from existing theranostic agents. This work highlights a theranostic application of MIL-88A@CuFe2O4 nanohybrids, demonstrating their potential as a unique multifunctional platform for precise cancer diagnosis and treatment.

In samples taken from iron meteorites, the presence of the nanocrystallites of FeNi with a L10 crystalline structure embedded in a complex matrix produces a magnetic behavior of the whole sample characterized by large magnetization at saturation and large coercive field. This has created expectations to obtain strong magnets without rare earths based on the L10 FeNi phase. In artificially synthetized samples containing several phases, the presence of the L10 phase was often deduced from the observation of coercive fields of several hundreds of Oe. Here, the microstructure and the magnetic behavior of crystallized microwires cast from Fe, Ni and P has been thoroughly analyzed. Microwires containing only two phases: plate-shaped, single-domain, nanocrystallites of the soft fcc (A1) FeNi phase embedded in a schreibersite (FexNi1-x)3P matrix show large room temperature coercivities of 440 Oe, which decrease substantially by cooling the sample below the Curie temperature of the matrix. It is shown experimentally that such behavior indicates that the origin of the high coercivity is the microstructure that isolates magnetically the crystallites of the soft FeNi A1 phase. The results point out that the presence or absence of L10-FeNi ordered phase is irrelevant in first order to achieve coercivity of hundreds of Oe in these types of alloys. In fact, it is the combination of microstructure and shape anisotropy that causes the high coercivity.

Summary Palaeomagnetic studies of impact glasses offer valuable insights into their magnetization processes and thermal histories associated with impact cratering events. Australasian tektites are broadly distributed in the largest and youngest strewn field of the Cenozoic, and they provide a unique opportunity to investigate the intensity of Earth’s magnetic field around 788 ka and potential impact-induced magnetic fields. The northern part of the Australasian strewn field covers South China, and it corresponds to the uprange zone of the impactor’s trajectory. Magnetic properties of Australasian tektites in South China may contain unique information about this impact event, but their palaeomagnetic characteristics remain poorly constrained. Here, we report the first palaeointensity data of Australasian tektites sampled from the Early-Middle Pleistocene strata in South China. The results show that Muong Nong-type tektites recorded palaeointensities of 30 ± 8 μT, consistent with the geomagnetic field intensity around 780–790 ka. These findings suggest that around 788 ka, Earth’s magnetic field had partially recovered from the earlier intensity decline associated with the precursor event of the Matuyama–Brunhes reversal. By contrast, the splash-form tektites in South China are characterized by extremely weak natural remanent magnetization and unstable magnetization components, posing challenges for deriving reliable palaeointensity data. Although strong impact-induced remanent magnetization was not detected in the samples, this study demonstrates that Australasian tektites, particularly Muong Nong-type, are well suited for palaeomagnetic studies that may reveal potential impact-induced magnetization.

Abstract Impact-generated shock waves can modify the remanent magnetization preserved in target rocks, yet their effects remain poorly constrained. Here we examine how shock waves modify rock magnetization by analysing unshocked granitoids and diorites, and shock-affected monomict breccia and impact melt rock of the Paleoproterozoic Dhala impact structure in India. Microscopic, thermomagnetic and hysteresis analyses were used to identify magnetic minerals and their domain states. Remanent magnetization and demagnetization experiments were performed to evaluate shock effects on the palaeomagnetic behaviour of impact-generated and unshocked target rocks. The unshocked rocks contain strong and stable magnetization carried by titanomagnetite. In contrast, the monomict breccia carries titanomagnetite and titanohematite and shows extremely weak and unstable magnetization, consistent with shock-related grain-size reduction and microfracturing. Impact melt rocks display intermediate behaviour, with titanomagnetite, titanohematite and pyrrhotite as magnetic carriers. These results show that shock can substantially reduce crustal magnetization. The results help to explain weak magnetic signatures at terrestrial and planetary impact structures, even in the presence of an ambient magnetic field.

Aflatoxin B1 (AFB1) is widespread in various kinds of food and poses a serious threat to health when it enters the human body via the food chain. This study aimed to establish a rapid and sensitive method for the detection of AFB1 and then combine it with HPLC for the quantitative analysis of AFB1 content. In this work, hydrothermal and sol-gel methods were employed to prepare aminoated magnetic nanoparticles featuring strong magnetism and excellent dispersion. Magnetic nanoparticles bound with antibodies can specifically capture AFB1 and then be combined with HPLC for the quantitative analysis of AFB1 content. Moreover, the key factors influencing the extraction efficiency, such as buffer type, adsorption time, elution time and volume, were optimized. The samples were spiked with AFB1 at low, medium, and high concentration levels of 5.0, 10.0, and 20.0 μg/kg, respectively. The established method exhibits good linearity within the range of 0.1-100 µg/kg, and the detection limit is as low as 0.09 µg/kg (S/N = 3). The recoveries in real samples ranged from 79.33% to 111.51%, with all relative standard deviations (RSDs) being less than 11.16% (n = 3 for each level). In conclusion, a rapid and efficient analytical method for detecting AFB1 in corn, peanut and oat based on functionalized immunomagnetic beads (IMBs) coupled with HPLC-FLD have been successfully developed .The method exhibited excellent sensitivity, featuring a low method detection limit of 0.09 μg/kg, high accuracy, and remarkable precision. In comparison to traditional sample preparation techniques, this IMBs-based approach presents substantial advantages in terms of simplicity, rapidity (completing sample processing within approximately 30 minutes), and cost-effectiveness. The IMBs possess excellent magnetic separation capabilities, which effectively streamline the pre-processing steps.

Cellulose-derived magnetic carbon nano-composites and their remediation role in dye wastewater.

Abstract Asteroid (16) Psyche is the largest likely metal‐rich asteroid in the Solar System and the target of the NASA Psyche mission. The mission aims to determine whether the asteroid is the core of a differentiated planetesimal that lost its mantle via a giant impact. To prepare for spacecraft observations of the asteroid, we combine impact and geodynamic models to predict the magnetization, composition, and interior structure of a mantle‐stripped core with the mass and density of Psyche. We show that Psyche‐like bodies can form from a single giant impact, with a hit‐and‐run collision being the most likely scenario. After the impact, Psyche's materials could have become magnetized while cooling in a dynamo field generated by its advecting core and/or in the magnetic field of the solar nebula. The former is diagnostic of Psyche being a mantle‐stripped core and is favored if Psyche's primordial sulfur content and current metal content are 10 wt.% and 50 wt.%, respectively. A sulfur content 10 wt.% delays core solidification long enough for kamacite in the asteroid's exterior to cool through the Curie temperature while the dynamo is still active. Formation of Psyche analogs with 50 wt.% metal content requires highly energetic impacts that more favorably occur after nebular‐gas dissipation. Therefore, if the Psyche spacecraft's Magnetometer, Gamma‐Ray Neutron Spectrometer, and Gravity and Topography Investigations respectively measure strong ( ) magnetization, sulfur‐rich surface provinces compatible with a bulk primordial sulfur content 10 wt.%, and metal content 50 wt.%, Psyche most likely formed as a mantle‐stripped core.

ABSTRACT We report an experimental study on the high‐pressure syntheses and characterizations of the samarium (Sm) hydrides system, for which the theoretical predictions have long struggled to accurately describe the crystal structures and superconducting properties. By laser heating Sm and ammonia borane (BH 3 NH 3 ) compressed in diamond anvil cells (DACs), we successfully synthesized a series of Sm hydrides, including P 6 3 / mmc SmH 9 , Im ‐3 m SmH 6 , I 4/ mmm SmH 4 , Pm ‐3 n SmH 3 , P 6/ mmm SmH 2 , and Fm ‐3 m SmH 2‐x . Electrical transport measurements performed in four independent experimental runs revealed metallic behavior without any signature of superconductivity, while some samples exhibited anomalies suggestive of magnetic or electronic transitions. These findings establish Sm hydrides as a model platform for probing the interplay between strong electronic correlations, magnetism, and superconductivity in high‐pressure hydrides, highlighting the complex role of 4 f electrons in governing their physical properties.

Abstract The global distribution of the Earth's lithospheric induced magnetization is examined through an inverse modeling approach that integrates constraints from both petrological data and satellite magnetic observations. The distribution of induced magnetization is characterized by the Vertical Integrated Susceptibility (VIS) of a spherical equivalent source layer. To reconstruct the long‐wavelength structures of the lithospheric magnetic field, a prior petrologically derived VIS model (SM3‐SI) is utilized to provide constraints at spherical harmonic degrees 0–16, while finer structures are constrained by satellite magnetic data. The resultant VIS model furnishes a higher‐resolution and more accurate depiction of lithospheric induced magnetization. Significant variations in the resultant VIS model across different crustal types and basement ages are confirmed through a comprehensive analysis. High lithospheric magnetization is generally observed in Precambrian provinces characterized by cold and thick lithospheres, whereas orogenic belts and extended crustal regions exhibit lower magnetization due to reduced magnetic materials from crustal thinning. In oceanic regions, elevated lithospheric magnetization is mainly concentrated in oceanic plateaus which are associated with Cretaceous magmatic activity. Mantle‐derived magnetic sources, which are related to an increased Curie depth caused by the cold subducted slabs and the serpentinization within the mantle wedge, are inferred to underlie the strong magnetization observed in island arcs and subduction zones.

Spinel ferrites are a class of magnetic materials that have attracted significant scientific interest because of their diverse functional properties and broad application potential. Among them, cobalt ferrite (CoFe₂O₄) is considered one of the most promising materials, as it combines moderate magnetic hardness with stable magnetic behavior. These features make it suitable for devices such as sensors, inductors, transformers, and magnetic storage media. In addition, the ability of cobalt ferrite to exhibit variable oxidation states, together with its high permeability and strong electrochemical stability, gives it distinctive physicochemical characteristics. In this work, CoFe₂O₄ nanoparticles were synthesized by the sol–gel combustion technique. The crystalline and chemical structure of the samples was examined by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FTIR). XRD analysis confirmed the formation of a single-phase cobalt ferrite spinel structure (ICSD 1533163, space group Fd3m). EDS revealed the presence of only cobalt, iron, and oxygen, indicating the absence of impurity elements. The FTIR spectrum demonstrated characteristic absorption bands associated with the spinel lattice, confirming the successful synthesis of CoFe₂O₄. The spinel lattice of cobalt ferrite consists of tetrahedral (A) and octahedral (B) sites, typically described as (Fe³⁺)ₐ(Co²⁺Fe³⁺)ᵦO₄. This structural arrangement imparts unique properties, including high catalytic efficiency, strong saturation magnetization, structural stability, low solubility of metal ions, and a relatively large surface area. Such a combination of characteristics makes CoFe₂O₄ particularly attractive for environmental applications, including wastewater treatment, where its magnetic nature enables easy separation and reuse.

The Goias Alkaline Province (GAP) is characterized by strong remnant magnetization and significant potential for nickel, copper, vermiculite and phosphate, among other resources. Several GAP complexes have previously been modelled using magnetic susceptibility inversion methods; however, these methods are not ideal due to the pronounced remnant magnetization of the rocks. A more detailed analysis is therefore necessary to better define the individual shape, emplacement styles and remnant magnetization values of these complexes. Magnetic vector inversion (MVI), considered the most suitable method for such conditions, was applied to all GAP complexes. As a result, ten new smaller complexes were identified and assigned to the GAP. The magnetic susceptibility characteristics obtained through MVI vary according to the lithology of the alkaline and host rocks, as well as the size of the modelled area. Consequently, it is not possible to assign a single magnetic susceptibility value to identify these complexes, and additional information is required. The geometry of the bodies is diverse, with emplacement types including pipe, T-shaped, funnel, finger-like and dyke forms. Three-dimensional magnetic inversion using MVI has proven to be a promising technique for refining known complexes and for detecting previously unmapped GAP bodies. Moreover, the methodology can be replicated for exploration in other geological contexts.

The CoPt nanowires(NWs) with a 100 nm diameter are grownby electrodepositionusing a single bath containing Pt and Co cations. The NWs are electrodepositedinto a porous membrane coated with a Pt(111) seed layer as the workingelectrode. The atomic structure, morphology, composition, and magneticproperties of CoPt NWs are investigated in detail using field emissionscanning electron microscopy (FE-SEM), high-resolution transmissionelectron microscope (HR-TEM), X-ray diffractometer (XRD), and vibrating-samplemagnetometer (VSM). Results indicate that the use of a Pt(111) seedlayer is crucial to controlling the microstructure of NWs. Specifically,a preferred (001) texture is obtained at constant potential E1 = −1000 mV (vs Ag/AgCl). Moreover,using periodic pulse deposition between E1 = −1000 mV and E2 = −700mV, one may modulate the Pt% content along the NWs. The work alsoexplores for the first time the case where E2 > E0, the Co2+/Costandard potential. It is demonstrated that the resulting NWs arecomposite. They are made of an alternation of metallic CoPt segmentsand Co oxide segments, where the CoPt segments present a strong (001)hcp structure, although the oxide presents a defective structure.A mechanism is proposed to interpret this result. From a magneticviewpoint, the CoPt NWs present a strong uniaxial magnetization anisotropyparallel to the NW axis, which is well-correlated with an hcp (001)texture of the metallic Co-rich segments. Quantitative analysis ofthe average magnetic moment confirms that CoOx segments have a negligiblecontribution to the total magnetic moment. Furthermore, MFM characterizationsshow that Co-rich CoPt NWs, deposited at a constant potential, haveuniform magnetization along the NW axis. A periodic magnetic contrastis observed for multilayered NWs prepared by pulse deposition.

Using the dynamics of charged test particles, we study the interplay of extremely strong gravitational and magnetic fields acting on ionized Keplerian disks. We assume a Schwarzschild spacetime of mass M combined with a dipole magnetic field represented by a dimensionless parameter b, characterizing the influence of fields near the gravitational radius . The particle dynamics can be realized in three regimes: gravitational (), magnetic (), and chaotic (). We demonstrate the ionization of disks that are originally both orthogonal and inclined to the magnetic field axis and consider both magnetic attraction and magnetic repulsion acting on the ionized particles. The case of secondary ionized equatorial charged disks is also discussed. The ionization in the dipole magnetic field is compared with the case of a Schwarzschild spacetime endowed with an asymptotically uniform magnetic field. The differences in the dipole and uniform fields are significant in the magnetic and chaotic regimes, while they are suppressed in the gravitational regime.