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Atomic‐level surface design of 2D materials, which benefits from their ultra‐high occupancy of surface atoms, has demonstrated significant potential for regulating electronic states. Despite efforts to explore heterojunctions on 2D surfaces, the stacking‐dominated surface electronic structures and their influences on dielectric polarization remain unclear. Herein, a confined growth strategy is proposed to accurately adjust the surface atom occupancy of MoS2 nanoflakes and thereby boost the polarization‐dominated microwave absorption (MA). By altering the stacking layer number from single layers to tens of layers of MoS2, the charge transfer from graphite substrate to MoS2 surface atoms, accompanied by the formation of local electric fields, reaches its highest intensity at two layers and then degrades dramatically with thicker MoS2 nanoflakes. The strengthened dielectric properties eventually enhance the MA performance, increasing the maximum absorption intensity (41.9 dB) by 346% and the effective absorption bandwidth (3 GHz) by 750%. These discoveries shed new light on the electronic modification of 2D materials and their electromagnetic functionalization. [ABSTRACT FROM AUTHOR]

1D magnetic fibers with significant morphological diversity and magnetic anisotropy are highly desirable for optimizing magnetic properties and electromagnetic responsiveness. However, it remains challenging for the precise control over internal magnetic interactions within each fiber. Herein, a strategy for self‐assembled magnetic coupling is taken to achieve the controllable reconstruction of continuous multiple coupling networks within a single fiber. High‐density ultrafine cobalt nanoparticles are uniformly embedded inside a carbon framework with a 1D multi‐channel structure (Co@MCF). This structure establishes a complex magnetic response system characterized by inherent inter‐fiber interactions and refined intra‐fiber self‐assembling coupling. The distinctive distribution of magnetic flux lines demonstrates enhanced magnetic sensitivity. This results in a minimum reflection loss of −57.65 dB and a broadband absorption frequency range of 7.28 GHz at 1.9 mm, effectively covers the entire Ku band and a substantial portion of the X band. The multi‐channel structure enhances the understanding of the relationship between microstructure and performance in magnetic fibers. Additionally, it positions Co@MCF as a highly competitive candidate for microwave absorption applications. [ABSTRACT FROM AUTHOR]

When interacting with an external Electromagnetic (EM) field, symmetric nanostructures, characterized by their periodic crystalline arrangement, typically resonate at specific frequencies. This resonance enhances local electromagnetic fields, leading to strong EM absorption, yet within a narrow absorption range. Conversely, asymmetric nanostructures, distinguished by their complex electric field polarization and distributions, provide broader frequency responses, albeit with generally weaker electromagnetic loss across the broadband. Therefore, striking a balance between wideband and strong absorption using either symmetric or asymmetric nanostructures remains a challenge. Here, a nanostructured epitaxial step‐growth technique is demonstrated that fabricates a CuxS multilevel rod‐like heterostructure with overall axial symmetry. This structure introduces localized asymmetry through variations in a component hierarchy and multilevel rod dimensions during the epitaxial growth process, effectively addressing the aforementioned balance between wideband and strong absorption. Experimental evidence and theoretical simulations confirm that nanostructures possessing these characteristics achieve efficient broadband absorption across a 6.3 GHz bandwidth with just 2.0 mm thickness, owing to the generation of multiple continuous local electric fields and enhanced electric field polarization. It is convincing that this methodology and design concept hold enlightening significance for advancing material and technological innovations in the realm of broadband absorption. [ABSTRACT FROM AUTHOR]

Recent observations of nontrivial spin textures and topological Hall effect (THE) in 2D van der Waals (vdW) ferromagnets have stimulated high interest in both fundamental physics and prospective spintronic applications. However, effectively manipulating spin textures and their exhibiting THE, which is the prerequisite for topology‐based 2D vdW devices, remains challenging. Here, the effective manipulation of the magnetic bubbles and THE is achieved in Fe5GeTe2 (FGT) crystals by utilizing Lorentz imaging and electrical transport measurements. The density and size of magnetic bubbles can be modulated effectively as the temperature and lamella thickness change, indicating the role of magnetocrystalline anisotropy and long‐range magnetic dipolar interaction is demonstrated, respectively. More importantly, the spin configurations of bubbles along with THE signal vary with sample thickness, demonstrating a topological transition between skyrmion bubbles and trivial bubbles. The key point lies in the presence or absence of Bloch lines in the stripe domain at different thicknesses. This study presents the reliable manipulations of spin textures and THE in FGT, which may provide valuable insights into the design of 2D vdW devices in spintronics. [ABSTRACT FROM AUTHOR]

By dispersing magnetic materials within various nanoscale structural frameworks, a complex and weavable magnetic network of nanoscale magnetic fields is created. This network not only systematically reconstructs interactions with external electromagnetic fields but also inversely adjusts its magnetic properties, potentially leading to anomalous or enhanced magnetic behaviors. However, the challenges lie in finding an effective nano‐framework capable of efficiently regulating magnetic flux lines and visualizing these reconstructed fields at the nanoscale. In this study, magnetic Co nanoparticles are strategically dispersed into a meticulously layered nanoporous framework with the bottom and upper nanopores exhibiting a staggered arrangement. The staggered nanoporous structure intricately shapes the magnetic flux lines into a Chinese knot shape, significantly altering its magnetic characteristics. The innovative use of advanced in situ magnetic holography, coupled with magnetic simulation calculations, has been instrumental in visualizing these modifications to the magnetic flux lines. Such a transformation remarkably enhances the material's efficacy in absorbing electromagnetic waves, covering the Ku band with remarkable efficiency even at a minimal thickness of 1.7 mm. Looking ahead, these breakthroughs not only provide a roadmap for developing more efficient electromagnetic wave absorbers but also open up new possibilities in manipulating magnetic properties for various advanced technological applications. [ABSTRACT FROM AUTHOR]

Micro-alloying of rare earth elements can improve the properties of Al alloys, but the mechanisms how they change the microstructures and therefore the properties of the alloys are still generally unclear. Using scanning electron microscopy and atomic-resolution transmission electron microscopy, here we have revealed the microstructural differences between two AlMgSi alloys with and without La-addition, and investigated the impacts of La-addition on specific microstructure-property relationships of the material. It is shown that La-addition has three significant effects on the microstructures and the properties of AlMgSi alloys. Firstly, La-addition changes the types of precipitates formed during aging. Most of β" precipitates formed in the peak-aged alloy with La-addition are polycrystalline β" precipitates. In the over-aging stage of this alloy, the dominant precipitates formed are the β"/U2, β"/β' and β'/U2 composite precipitates, rather than the expected β' precipitates. Secondly, La-addition induces the formation of numerous FCC AlSiLa intermetallics, which significantly refine the grain size and enhance the strength and the ductility of the alloy. Thirdly, La-addition may enhance the electrical conductivity of the age-hardened alloy by reducing the solute atoms in the Al-matrix. [Display omitted] • Microstructure changes of an AlMgSi alloy induced by La-addition are revealed. • Polycrystalline β" precipitates form in the peak-aged alloy with La-addition. • Multiphase composite precipitates form in the over-aged alloy with La-addition. • AlSiLa intermetallics improve the La-added alloy's strength and ductility. • Reduced solutes account for the La-added alloy's improved electrical conductivity. [ABSTRACT FROM AUTHOR]

We introduce the largest abdominal CT dataset (termed AbdomenAtlas) of 20,460 three-dimensional CT volumes sourced from 112 hospitals across diverse populations, geographies, and facilities. AbdomenAtlas provides 673 K high-quality masks of anatomical structures in the abdominal region annotated by a team of 10 radiologists with the help of AI algorithms. We start by having expert radiologists manually annotate 22 anatomical structures in 5,246 CT volumes. Following this, a semi-automatic annotation procedure is performed for the remaining CT volumes, where radiologists revise the annotations predicted by AI, and in turn, AI improves its predictions by learning from revised annotations. Such a large-scale, detailed-annotated, and multi-center dataset is needed for two reasons. Firstly, AbdomenAtlas provides important resources for AI development at scale, branded as large pre-trained models , which can alleviate the annotation workload of expert radiologists to transfer to broader clinical applications. Secondly, AbdomenAtlas establishes a large-scale benchmark for evaluating AI algorithms—the more data we use to test the algorithms, the better we can guarantee reliable performance in complex clinical scenarios. An ISBI & MICCAI challenge named BodyMaps: Towards 3D Atlas of Human Body was launched using a subset of our AbdomenAtlas, aiming to stimulate AI innovation and to benchmark segmentation accuracy, inference efficiency, and domain generalizability. We hope our AbdomenAtlas can set the stage for larger-scale clinical trials and offer exceptional opportunities to practitioners in the medical imaging community. Codes, models, and datasets are available at https://www.zongweiz.com/dataset. • AbdomenAtlas: The largest abdominal CT dataset of 20,460 per-voxel annotated CT volumes from 112 hospitals. • SuPreM: A suite of pre-trained 3D models enabling efficient transfer learning and few-shot learning. • BodyMaps: An open algorithmic benchmark offering 9K and 5K annotated CT volumes for training and testing. • We develop a semi-automatic annotation procedure for constructing large-scale medical imaging datasets. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterointerface design tailored electron structure and electromagnetic properties. • A diffusion-driven self-assemble strategy created porous magnetic microspheres. • Core-shell NiFe 2 O 4 @PPy possessed broadband absorption with a wide EAB of 6.8 GHz. • High-density magnetic ferrite-polymer heterointerfaces enhanced polarization loss. • Hierarchical cavities in porous structures created confined magnetic coupling. Heterointerface engineering originated from structure design is a promising approach to develop high-performance electromagnetic (EM) absorption materials but remains challenges in revealing the EM modulation mechanism. In this work, a diffusion-driven self-assemble strategy was proposed to construct porous NiFe 2 O 4 microspheres with rich confined cavities. Followed by an in-situ vapor phase polymerization, conductive polypyrrole (PPy) layers were tightly coated on NiFe 2 O 4 surface, building numerous ferrite-polymer heterointerfaces. Systematic investigation demonstrated that the controllable coating thickness and porous structure were crucial to regulate the component dependency EM properties and the dielectric-magnetic balance. Accordingly, these activated heterointerfaces and lattice defects inevitably produced polarization response to enhance the dielectric loss, and the confined magnetic coupling among hierarchical cavities strengthened the magnetic loss, jointly contributing to the boosted dissipation of incident EM energy. Owing to the synergy merits, optimum core–shell NiFe 2 O 4 @PPy microspheres exhibited an impressive broadband EM absorption performance with a wide effective absorption bandwidth covered 6.8 GHz at 2.62 mm. This study provides methodological guidance to design magnetic-dielectric EM absorption materials, and deciphers the mechanism of structure-interface modulated EM properties. [ABSTRACT FROM AUTHOR]

The burgeoning advancement of electronic technology and wireless communications has opened up an unprecedented era of electromagnetic wave applications, but the accompanying issues of electromagnetic pollution are equally deserving of profound attention. In recent years, a variety of novel electromagnetic absorbers have been ingeniously designed and actively emerged, among which carbon-based materials have become one of the most promising alternatives for next-generation electromagnetic functional materials, owing to the low density, tunable electrical properties, high stability, and chemical tolerance. This article comprehensively reviews the current research status and frontier science of carbon-based absorbing materials serving in microwave frequency band, and discusses in detail the microwave absorption mechanisms of various carbon-based systems as well as the critical factors affecting microwave attenuation. Furthermore, strategies to optimize microwave absorption performance of carbon-based materials through component design, structural modification, morphology modulation, and composite approaches will be discussed, with particular emphasis on their intrinsic correlation with magnetic-dielectric loss characteristics. Finally, the urgent requirements for improving carbon-based absorbing materials and insights into future development are provided, covering from material design to performance optimization to device-based applications. This review endeavors to support valuable references for research on carbon-based microwave absorbing materials and to stimulate further innovative thinking. [Display omitted] [ABSTRACT FROM AUTHOR]