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The fabrication of nanometer‐sized magnetic heterostructures with controlled magnetic components and specific interfaces holds great significance in the field of electromagnetic (EM) wave absorption. However, the process of achieving these structures still poses significant challenges. Here, abundant magnetic heterostructures are successfully fabricated by utilizing the surface energy anisotropy differences of the nonasymmetric hammer‐shaped interface to support the nucleation and growth of magnetic heterostructure components while effectively inhibiting their aggregation. Through a confined growth strategy via in situ growth of FeOOH and sequentially precise thermal treatments, dispersion of the heterostructures is achieved at the nanometer scale, while also observing a high degree of chemical stability due to occurrence of a charge‐compensation effect at the interface. Consequently, a series of magnetic heterostructures are obtained via phase translations of FeOOH precursors. The nanometer‐sized heterostructures demonstrate multilevel interfacial polarization effects. Furthermore, the hierarchical core–shell structure of the heterostructures promotes anisotropic polarization absorption. As a result, the multiple interfaces and nanometer‐sized Fe/Fe3O4@SiO2@Fe‐2 heterostructures demonstrate improved EM wave attenuation performance. Remarkably, they achieve an absorption bandwidth of 9 GHz at a thickness of 1.8 mm. A novel avenue is introduced here for investigating the intricate relationship between structure and properties in magnetic heterostructures. [ABSTRACT FROM AUTHOR]

Simultaneously developing protective electronics film for multi‐spectra, including the radar, infrared (IR), and visible ranges, for both the military and civilian sectors is extremely challenging. The existing multi‐spectra‐compatible materials mainly concentrate on either the radar/IR or IR/visible bands, trailing the rapid evolution of advanced devices for monitoring electromagnetic signals. Here, it is designed and fabricated an ultra‐thin MXene‐based composite film (20 µm) containing black phosphorus (BP) and Ni chains (M‐B‐M(Ni)) with integrated highly efficient thermal IR stealth, visible light absorption, and electromagnetic wave shielding. M‐B‐M(Ni) exhibits an extremely low IR emissivity of 0.1, decreasing the radiation temperature difference between the surrounding environment and target device. BP offers a high solar absorptance of 80%, which guarantees energy conversion from visible light to heat. Moreover, the absorption proportion of the electromagnetic shielding effectiveness for M‐B‐M(Ni) is 16% higher than that of pure MXene films (68.7%), owing to the improved magnetic loss by decoration with magnetic Ni chains. Due to the combined merits of MXene, BP, and Ni chains, M‐B‐M(Ni) opens an avenue for the construction of advanced multi‐spectra compatible materials for versatile applications in thermal IR stealth, electromagnetic wave shielding, and energy transformation. [ABSTRACT FROM AUTHOR]

Metal halide perovskite quantum dots (QDs) have emerged as potential materials for high brightness, wide color gamut, and cost‐effective backlight emission due to their high photoluminescence quantum yields, narrow emission linewidths, and tunable bandgaps. Herein, CsPbX3/SBA‐15 nanocomposites are prepared with outstanding optical properties and high stability through an in situ growth strategy using mesoporous silica particles. According to finite‐difference time‐domain simulations, the mesoporous structure provides a strong waveguide effect on perovskite QDs and the uniform dispersion suppresses reabsorption losses, improving the overall photoconversion efficiency of perovskite QDs. The as‐fabricated perovskite monochromatic light‐emitting diode (LED) has a maximum luminous efficiency of 183 lm W−1, which is the highest for monochromatic perovskite LEDs reported to date. A further benefit of this work is that the white devices, which combine the green and red perovskite nanocomposites with commercial blue LED, exhibit a high luminous efficiency of 116 lm W−1 and a wide color gamut (125% for NTSC and 94% for Rec. 2020) with coordinates of (0.33,0.31). [ABSTRACT FROM AUTHOR]

The erosion threshold, beyond which bed sediments start to move, is a key parameter describing sediment transport processes. For silt‐dominated mixtures, in which the grain size is between sand and clay, existing experimental studies exhibit contradictory observations. That is, the erosion was either sand‐like or clay‐like, suggesting transitional erosion behavior. To explore the underlying mechanism of the transitional erosion behavior of silt‐sized sediment, we revisited the topic of the erosion threshold of sand‐silt mixtures by carrying out a series of erosion experiments for different bed compositions. The results suggest that there exists a critical silt content of approximately 35%, separating two domains. Below this critical value, the critical bed shear stress follows the Shields criterion, whereas above this value, the erosion threshold of a mixed bed increases abruptly and remains relatively constant with a further increase in silt content. By combining with existing data, we found that the proposed critical silt content acts as a tipping point, beyond which the mixed bed shifts from a sand‐dominated to a silt‐dominated domain. For the silt‐dominated domain, a stable silt skeleton can be formed by attraction forces that resist erosion. However, the attraction forces are too weak to form a stable silt skeleton when the silt content is too small. Based on this finding, a modified critical bed shear stress formula is proposed for silt‐dominated mixtures, which results in a better agreement with experimental data (an averaged bias of 10%), performing better than existing formulas (larger than 30%). Plain Language Summary: When exposed to a certain flow velocity, sediment particles are dislodged from the seabed, namely, the erosion threshold. Attributed to sizes, shapes, minerals, etc., sediments of different grain sizes behave differently, resulting in various erosion behaviors. Sand particles (62.5–2,000 μm) are not sticky and erode particle by particle, whereas clay particles (<4 μm) are sticky and collectively erode as chunks. Silt (4–62.5 μm), of which the grain size is between sand and clay, exhibits either sand‐like or clay‐like behavior, suggesting transitional erosion behavior. Coastal sediments are usually mixtures of clay, silt, and fine sand. Different bed compositions result in different erosion behaviors, leading to a variety of bed forms, morphological patterns, etc. Therefore, a thorough understanding of the erosion behavior of sediment mixtures is of great significance to the topic of coastal sediment transport, which further benefits coastal geomorphology, ecology, etc. This study indicates that, for sand‐silt mixtures, a critical silt contents exists, beyond which the bed mixtures shift from a sand‐like erosion behavior to a clay‐like erosion behavior. The widely adopted parameterized expression of the erosion threshold (namely, the Shields curve) is modified to mimic the transitional erosion behavior of sand‐silt mixtures by considering the effects of silt content. Key Points: Silt content is an important factor controlling the erosion of sand‐silt mixtures in regards to noncohesive or cohesive propertiesThere exists a critical silt content of 35%, beyond which a stable silt skeleton is formed that increases the erosion thresholdA modified critical bed shear stress is proposed to mimic the transitional erosion behavior of sand‐silt mixtures [ABSTRACT FROM AUTHOR]

Heterointerface engineering is evolving as an effective approach to tune electromagnetic functional materials, but the mechanisms of heterointerfaces on microwave absorption (MA) remain unclear. In this work, abundant electromagnetic heterointerfaces are customized in multilevel hollow architecture via a one‐step synergistic polymerizing‐etching strategy. Fe/Fe3O4@C spindle‐on‐tube structures are transformed from FeOOH@polydopamine precursors by a controllable reduction process. The impressive electromagnetic heterostructures are realized on the Fe/Fe3O4@C hollow spindle arrays and induce strong interfacial polarization. The highly dispersive Fe/Fe3O4 nanoparticles within spindles build multi‐dimension magnetic networks, which enhance the interaction with incident microwaves and reinforce magnetic loss capacity. Moreover, the hierarchically hollow structure and electromagnetic synergistic components are conducive to the impedance matching between absorbing materials and air medium. Furthermore, the mechanisms of electromagnetic heterointerfaces on the MA are systematically investigated. Accordingly, the as‐prepared hierarchical Fe/Fe3O4@C microtubes exhibit remarkable MA performance with a maximum refection loss of −55.4 dB and an absorption bandwidth of 4.2 GHz. Therefore, in this study, the authors not only demonstrate a synergistic strategy to design multilevel hollow architecture, but also provide a fundamental guide in heterointerface engineering of highly efficient electromagnetic functional materials. [ABSTRACT FROM AUTHOR]

Methamphetamine (METH) abuse has become a global public health problem. However, the potential mechanisms involving METH‐induced metabolic disorders have thus far remained poorly understood. Metabolomics can provide a clue for the cause of apparent changes and consequently be used to investigate the METH‐induced dysregulation of metabolite expression and the mechanism of metabolic disorder mechanism. This laboratory investigation included 80 METH abusers and 80 healthy people. The serum metabolites were detected and analysed by gas chromatography/time‐of‐flight mass spectrometry. Raw data were processed with the software MS DIAL, which includes deconvolution, peak alignment and compound identification. The data matrix was processed by univariate and multivariate analyses for significant metabolite screening with the criteria of variable importance in projection values > 1, fold change > 1.5 and the t test (p value < 0.05). Significant differences in 16 metabolites (deoxycholic acid, cholic acid, hydroxylamine, etc.) in serum were found between the METH abuse group and the control group. Energy metabolic pathways and several amino acid metabolic pathways (alanine, aspartic acid and glutamate metabolism and tryptophan metabolism) were primarily involved. Further analysis indicated that the area under the receiver operating characteristic curve (AUC) was 0.998 for these 16 metabolites. Among the metabolites, three carbohydrates (d‐ribose, cellobiose and maltotriose) had an AUC of 0.975, which were determined as potential markers of abuse. We observed metabolic disturbances in METH abusers, particularly perturbation in energy metabolism and amino acid metabolism, which can provide new insights into the search for biomarkers and the mechanisms underlying the adverse effects of METH on human health. [ABSTRACT FROM AUTHOR]

Abstract: Flexible supercapacitors have potential for wearable energy storage due to their high energy/power densities and long operating lifetimes. High electrochemical performance with robust mechanical properties is highly desired for flexible supercapacitor electrodes. Usually, the mechanical properties are improved by choosing high flexible textile substrates but at the much expense of electrochemical performance due to the nonideal contact between conductive materials and textile substrates. Herein, the authors present an efficient, scalable, and general strategy for the simultaneous fabrication of high‐performance textile electrodes and yarn electrodes. It is interesting to find that the conformal reduced graphene oxide (RGO) layer is uniformly and successively painted on the surface of SnCl2 modified polyester fibers (M‐PEF) via a repeated “dyeing and drying” strategy. The large‐area textile electrodes and ultralong yarn electrodes are fabricated by using RGO/M‐PEF as substrate with subsequent deposition of polypyrrole. This work provides new opportunities for developing high flexible textile electrodes and yarn electrodes with further increased electrochemical performance and scalable production. [ABSTRACT FROM AUTHOR]

A new carbon nanofiber codoped with nitrogen and phosphorus (NPCNF) that has a high specific surface area and good electrocatalytic properties for the oxygen reduction reaction (ORR) was synthesized using a template-free method. The fabrication process involves the pyrolysis of phytic acid doped polyaniline aerogel. A nonaqueous Li-O2 battery with a specific capacity as high as 12 607 mA h g−1 was constructed by using an oxygen electrode based on NPCNFs supported by Ni foam. The NPCNF electrode showed a lower overpotential than pure carbon. The observed excellent electrochemical performance could be because of the unique foamlike N- and P-codoped carbon microstructure, which had a high ORR catalytic activity. These results indicate that the use of NPCNF as a cathode material could be a feasible approach to obtain a high-capacity Li-O2 battery. [ABSTRACT FROM AUTHOR]

The Cover shows a new carbon nanofiber codoped with nitrogen and phosphorus (NPCNF) that was fabricated by pyrolysis of phytic acid doped polyaniline aerogel. The NPCNF shows an extremely high discharge capacity and good catalytic activity towards the oxygen reduction reaction as oxygen electrodes in nonaqueous Li‐O2 batteries.In their Full Paper, C. Xu et al. explain that the observed excellent electrochemical performance could be a result of the unique foamlike N‐ and P‐codoped carbon microstructure. These results show that the use of NPCNF as a cathode material could be a feasible approach to obtain a high‐capacity Li‐O2 battery. More information can be found in the Full Paper by C. Xu et al. on page 3725 in Issue 24, 2016 (DOI: 10.1002/cctc.201601005). [ABSTRACT FROM AUTHOR]