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An efficient chalcogenative annulation strategy for constructing functionalized saturated N-heterocycles from unactivated alkenes with dichalcogenides under electrochemical conditions has been presented. This protocol is applicable to mono-, di- or tri-substituted alkenes, providing a straightforward pathway to aziridines, azetidines, pyrrolidines, and piperidines with high regioselectivity. Moreover, the strategy is qualified to realize the oxychalcogenation of alkenes as well. [ABSTRACT FROM AUTHOR]

Advancing the integration of nonliving and living components relies heavily on functional hydrogel materials with biocompatibility and customizability. In this study, an enzyme‐assisted surface activation method is developed to produce reactive hydrogel microparticles (HMPs) comprising thiolated hyaluronic acid and hyperbranched poly(β‐hydrazide esters). Fluorescence labeling analysis reveals an over six‐fold increase in surface‐active functional group density on the hydrogels and three‐fold on HMPs after enzyme activation. This enhancement improves accessibility of active elements, facilitating post‐functionalization and optimizing their capacity to support initial cell adhesion and spreading as carriers for cell cultures. Additionally, by utilizing the exposed reactive double bonds on the HMP surfaces post‐enzymatic treatment, thiolated HMPs are produced through a thiol‐ene coupling reaction with thiolated polymers. These thiolated HMPs bond together spontaneously, resulting in the formation of annealed granular hydrogels with interconnected large‐pore networks and a tunable storage modulus (G') from tens to hundreds of pascals, compatible with most soft tissues. Integrated with 3D bioprinting, this hydrogel ink generates prints that foster cell adhesion, migration, growth, and network formation. Moving forward, integrating various granular hydrogel scaffold systems with the enzyme‐assisted activation technique holds significant promise for enhancing performance and expanding applications in regenerative medicine and innovative living materials. [ABSTRACT FROM AUTHOR]

Cr3+ ions doped broadband emission near‐infrared (NIR) phosphors are pertinent to widespread emerging applications and get rapid developed. However, it remains a challenge to simultaneously achieve highly efficient and broadband near‐infrared emission in Cr3+ ions doped phosphors. Herein, the Cr3+ ions firstly doped into organic–inorganic hafnium chlorine TEA2HfCl6 (TEA = Tetraethylammonium, C8H20N), which show broadband emission at a range of 700–1300 nm, a full width at half maximum (FWHM) of 164 nm, and a high photoluminescence quantum yield (PLQY) of 60%. The organic–inorganic metal halides show huge advantages than traditional inorganic phosphors, like high luminescence efficiency, low temperature solution synthesis progress, and low cost, which provide an efficiency strategy for lighting industry. Based on these advantages, a high power NIR light emitting diode (LED) is fabricated by TEA2HfCl6:Cr3+ with a high‐power 530 nm chip, which is used in food analysis, night vision, and biomedical imaging as a demonstration. This work indicates the feasibility of organic–inorganic metal halides as host materials for developing Cr3+ ions emitting phosphor toward multi‐optoelectronic applications. [ABSTRACT FROM AUTHOR]

Microcracks and surface heterogeneity in solid‐electrolyte interphase (SEI) induced by repeated plating/stripping of lithium (Li) metal exacerbate SEI fracture propagation and dendrite growth, which lead to unsatisfactory Coulombic efficiency and limited cycle life of Li metal anode. In this study, the hybrid artificial interfaces with controlled organic–inorganic ratios are designed and deep insight into their impacts on the electro‐chemo‐mechanical properties is obtained. The organic–inorganic ratios in the hybrid interfaces influence the mechanical properties, lithiophilicity, and diffusion kinetics of the interfaces, which in turn affect the nucleation, early growth, and repeated deposition/dissolution behavior of Li. It is found that increasing the inorganic ratio in the hybrid interface can realize significantly enhanced electrochemical performances. This work answers a key question for hybrid interfaces: should organic‐rich or inorganic‐rich be preferred in the hybrid interface? It is believed that this work will guide the future design of hybrid interfaces for Li metal anode and open up opportunities for the realization of next‐generation Li metal batteries. [ABSTRACT FROM AUTHOR]

The term "light yield" (LY) refers to the ability of scintillator materials to convert high‐energy radiation into visible light. A higher LY corresponds to improved energy and spatial resolution in detectors. The enhancement of scintillator material performance is a crucial aspect of their development. In this study, the Cs2TeCl6 (CTC) double perovskite microcrystals is synthesized, and the broadband yellow emission shows a high degree of matching with the Charge‐coupled Device (CCD). However, the LY of CTC is poor for practical applications in X‐ray imaging. The scintillation performance is significantly enhanced through hafnium alloying. The LY increased from ≈4167 to 38 523 photons/MeV, and the detection limit decreased from 948 to 258 nGy s−1. The underlying mechanism of Te4+ ions emission is systematically explored through density function theory (DFT) analysis, along with investigations into pressure‐dependent photoluminescence, temperature‐dependent photoluminescence, and low‐temperature thermoluminescence. Furthermore, a flexible X‐ray scintillator screen with an outstanding high spatial resolution of 15.9 lp mm−1 is successfully fabricated. This work not only represents a substantial advancement in the scintillation performance of Te4+ ions emission double perovskite microcrystals but also provides an effective strategy for the development of the next generation of halide scintillators. [ABSTRACT FROM AUTHOR]

This study evaluates the feasibility of producing high-strength low-alloy (HSLA) steel using advanced wire-fed laser additive manufacturing (LAM-W) and wire arc additive manufacturing (WAAM) technologies. Optimized parameters were independently developed for each heat source, utilizing a self-designed HSLA steel wire as the feedstock. Microstructural features and mechanical properties of the fabricated steels were characterized and compared, taking into account differences in heat input and cooling rates. LAM-W samples exhibited a finer columnar grain microstructure, while both LAM-W- and WAAM-produced steels predominantly showed lower bainite and granular bainite microstructures. LAM-W demonstrated higher strength and hardness, lower ductility, and comparable low-temperature toughness compared to WAAM. Both processes demonstrated an excellent balance between strength and ductility, with absorbed energy exceeding 100 J at −40 °C. The study confirms the feasibility of producing high-strength and tough HSLA steel parts using LAM-W and WAAM technologies, and compares the advantages and disadvantages of each method. These findings assist in selecting the most suitable wire-fed AM process for HSLA steel fabrication at high deposition rates. [ABSTRACT FROM AUTHOR]

Raman spectroscopy is very sensitive to the U‐O bonding strength changes under high pressure, and it could reveal important information about the bonding and stoichiometry of the U‐O systems. The pressure and temperature (P–T) phase diagram of U3O8 was investigated by Raman spectroscopy via four independent P–T experimental paths. The phase boundaries between different phases have been determined by the changes in Raman spectra. A new phase (α′‐U3O8) was observed below 233 K at 0.6 GPa or 198 K at zero pressure accompanied by the discontinuities in Raman wavenumber and the new shoulder peak near the B2(6) Raman modes. Upon compressing at low temperature (123 K), the high‐pressure irreversible phase transition from orthorhombic to cubic structure (α′‐δ) was observed at around 11.3 GPa, evidenced by the merging of B2(6) and B′2(6) Raman modes. [ABSTRACT FROM AUTHOR]

Mangrove ecosystems are pivotal to the global carbon budget. However, there is still a dearth of research addressing the impact of regional mangrove land use and land cover change (LUCC) on carbon sequestration and its associated spatial distribution patterns. To investigate the impact of different development scenarios on the carbon storage capacity of mangrove ecosystems, we focused on Hainan Island. We used LUCC data from 2010 to 2020 from mangrove-inhabited regions. The Markov-PLUS model was applied to predict the spatiotemporal dynamics of mangrove coverage under the natural increase scenario (NIS) and the mangrove protection scenario (MPS) over the next 40 years. Carbon storage was estimated using the InVEST model based on field-measured carbon density data. The outcomes show the following: (1) The Markov-PLUS model, with an overall accuracy of 0.88 and a Kappa coefficient of 0.82, is suitable for predicting mangrove distribution patterns on Hainan Island. (2) Environmental factors were the main drivers of historical mangrove changes on Hainan Island, explaining 54% of the variance, with elevation, temperature, and precipitation each contributing over 13%. (3) From 2025 to 2065, the mangrove area on Hainan Island is projected to increase by approximately 12,505.68 ha, mainly through conversions from forest land (12.73% under NIS and 12.37% under MPS) and agricultural land (39.72% under NIS and 34.53% under MPS). (4) The carbon storage increment within Hainan Island's mangroves is projected at 2.71 TgC over the whole island, with notable increases expected in the eastern, northern, and northwestern regions, and modest gains in other areas. In this study, we comprehensively investigated the spatiotemporal dynamics and future trends of carbon storage in the mangroves of Hainan Island, offering invaluable guidance for the long-term management of mangrove ecosystems and the realization of carbon neutrality goals by 2060. [ABSTRACT FROM AUTHOR]