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The prognosis for traumatic brain injury (TBI) depends largely on prompt hemostasis and effective pharmacologic interventions. Natural all‐small‐molecule self‐gelling powder, integrating the advantages of self‐assembled small‐molecule hydrogels and powders, is expected to provide timely and effective prehospital management of TBI. However, the synthesis and application of natural all‐small‐molecule self‐gelling powder is still uncharted territory. In this study, an all‐small‐molecule co‐assembled MGF‐H3BO3‐RUT (MBR) self‐gelling powder is fabricated through the co‐assembly of mangiferin (MGF) and rutin (RUT) in H3BO3/NaOH aqueous solution. Both compounds can bind with boric acid, leading to co‐assembling into hydrogels through hydrogen‐bonding interactions and π–π stacking. MBR self‐gelling powder is then obtained by drying the as‐prepared hydrogels, thus integrating hemostasis and pharmacodynamics into one. Remarkably, it displays robust regeneration capabilities, while retaining excellent self‐healing properties and injectability after drying‐hydration cycles. Moreover, MBR self‐gelling powder not only achieves rapid effective hemostasis but also attenuates conspicuously cerebral edema and inflammatory response after TBI by in situ spraying, exhibiting notable neuroprotective effects without discernible toxic side effects. This study provides a novel assembly strategy and application form for self‐assembled gel materials originating from natural small molecules, offering promising avenues for the treatment of TBI in the acute phase. [ABSTRACT FROM AUTHOR]

Recently, passive radiative cooling (PRC) that realizes thermal management without consuming any energy has attracted increasing attention. However, few studies focus on low‐cost and robust PRC film fabricated by a facile and environmentally friendly method. In this study, via coextrusion blow film molding and water leaching, sandwiched PRC film (SPRCF) is efficiently prepared, and its skin and core layer are respectively high‐density polyethylene (HDPE) film and oriented ZnO@HDPE microfiber layer. Of note, such a sandwiched structure enables SPRCF to possess remarkable mechanical properties, abrasion, and weather resistance. Moreover, with the introduction of ZnO, SPRCF shows lower sunlight transmittance (≈3.8%) but higher mid‐infrared transmittance (≈88.8%), endowing it with remarkable PRC performance (the maximum cooling power of daytime and nighttime are respectively 73.8 and 96.7 W m−2). Furthermore, the decent self‐cleaning performance of SPRCF‐45 endows it with maintenance‐free features outdoors. This work proposes a facile and environmentally friendly method for preparing low‐cost and robust SPRCF, opening a new pathway to develop PRC film following the concept of polymer "structuring" processing. [ABSTRACT FROM AUTHOR]

In recent years, flexible stress sensors and their multifunctional applications in the fields of human motion monitoring, electromagnetic pollution prevention, and thermal management have received more and more attention. There is no doubt that the characteristics of conductive fillers are closely related to their sensing performance and multifunctionality. As a two-dimensional material with high conductivity, high strength, excellent light-to-heat conversion efficiency, and hydrophilicity, MXenes have been proven to be potential fillers for the synthesis of multifunctional stress sensors. Therefore, we systematically review the research progress on MXene-based stress sensors, including tensile sensors, pressure sensors, and bending/torsion sensors, and their synthesis methods and structural characteristics are also discussed in detail. In addition, this review also introduces and discusses the multifunctional applications of MXene-based stress sensors based on the characteristics of MXenes and sensor substrates. Finally, the challenges that MXenes face in sensor applications and the expected development trends are presented, and the future development prospects of multifunctional MXene-based stress sensors are also presented. [ABSTRACT FROM AUTHOR]

Highlights: The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment. A lightweight flexible thermally stable composite is fabricated by combining silica nanofiber membranes (SNM) with MXene@c-MWCNT hybrid film. The flexible SNM with outstanding thermal insulation are prepared from tetraethyl orthosilicate hydrolysis and condensation by electrospinning and high-temperature calcination; the MXene@c-MWCNTx:y films are prepared by vacuum filtration technology. In particular, the SNM and MXene@c-MWCNT6:4 as one unit layer (SMC1) are bonded together with 5 wt% polyvinyl alcohol (PVA) solution, which exhibits low thermal conductivity (0.066 W m−1 K−1) and good electromagnetic interference (EMI) shielding performance (average EMI SET, 37.8 dB). With the increase in functional unit layer, the overall thermal insulation performance of the whole composite film (SMCx) remains stable, and EMI shielding performance is greatly improved, especially for SMC3 with three unit layers, the average EMI SET is as high as 55.4 dB. In addition, the organic combination of rigid SNM and tough MXene@c-MWCNT6:4 makes SMCx exhibit good mechanical tensile strength. Importantly, SMCx exhibit stable EMI shielding and excellent thermal insulation even in extreme heat and cold environment. Therefore, this work provides a novel design idea and important reference value for EMI shielding and thermal insulation components used in extreme environmental protection equipment in the future. [ABSTRACT FROM AUTHOR]

The addition of CaCO3 powder in calcium aluminate cement (CAC) is reported to accelerate the hydration of CAC and generate mono‐carbonate C4AC̅H11, which is conducive to shortening the curing time of CAC‐bonded castables at ambient temperatures. Although the hydration of CAC is relatively fast, there is still residual un‐hydrated CAC in castables after curing. The residual CAC would continue to hydrate to produce C3AH6 and AH3 during the subsequent drying procedures in the absence of CaCO3. But it is worth pondering which type of hydrate would be generated in the presence of CaCO3 during the drying at around 110°C. In this study, the effect of micro‐sized CaCO3 addition on the hydrate formation of CAC‐bonded castables during drying at 110°C was investigated. The results indicate that the C4AC̅H11 formed at the curing temperature of 30°C is not decomposed or converted during drying. The CaCO3 remained after curing does not participate in the hydration of residual CAC during drying at 110°C, and thus the residual CAC continues to hydrate to generate C3AH6 rather than C4AC̅H11. [ABSTRACT FROM AUTHOR]