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The faradaic efficiency of Bi2WO6 is 62.0% at −0.3 V vs. RHE, an improvement of 1.4- and 1.8-times relative to Bi2O3 and WO3 for the nitrate reduction reaction. In addition, the catalysis occurring on Bi2WO6 follows the pathway: *NO3–*NO2–*NO–*NOH–*HNOH–*H2NOH–*NH3, as verified by operando Raman spectroscopy and theoretical calculations. [ABSTRACT FROM AUTHOR]

High entropy alloy nanoparticles encapsulated into nitrogen-doped carbon nanotubes show superior bifunctionality for the ORR and OER, evidenced by a battery performance of 214 mW cm−2, sustained for 200 h. [ABSTRACT FROM AUTHOR]

The return stroke of cloud‐to‐ground (CG) lightning is an impulsive radiator of very low‐frequency/low‐frequency (VLF/LF) electromagnetic signals allowing for the remote sensing of lower ionosphere over large spatial coverage. In this study, we examined the LF magnetic fields measured in Malacca, Malaysia, to probe reflection heights of the lower ionosphere near the equator on three different nights in 2021. The results show that the virtual ionospheric height at nighttime typically ranged from 82.0 to 90.0 km, with a mean value of 85.3 km. Our measurements also revealed significant variations in the virtual ionospheric height across different regions over a spatial scale of about 800 km. The maximum height difference was about 5.0 km. Moreover, the fluctuation characteristics are observed in both estimated ionospheric height and calculated peak reflection ratio during similar periods. This fluctuation may be related to atmospheric gravity waves in the nighttime ionosphere. In addition, we compared the virtual ionospheric height estimated from CG strokes of different polarities, and the results showed that the virtual reflection height for positive CG strokes is lower than that for negative ones. Plain Language Summary: The ionosphere is the border zone between Earth's atmosphere and exterior space environment. The lowest part of ionosphere, at the altitude range of 60–100 km is particularly tough to measure and impacts both ground‐to‐ground and satellite‐to‐ground communications. Due to the limited coverage range of artificial very low‐frequency and low‐frequency (VLF/LF) techniques by a fixed number of transmitters, the global distribution of broadband radio atmospherics, or sferics, originating from cloud‐to‐ground (CG) lightning strokes has higher detection efficiency. These sferics propagating hundreds of kilometers provide a higher signal‐to‐noise ratio and more detailed information on the lower ionosphere. Currently, the applications of lightning‐induced electromagnetic pulses for remote sensing the lower ionosphere are primarily focused on mid‐to‐high latitude regions. Despite being a hotspot of lightning, there is still a lack of related research in the equatorial areas. Therefore, this study aims to investigate nighttime ionospheric variations using LF magnetic fields generated by lightning strokes in the equatorial region near Malacca, Malaysia, to fill the gap in this field. Our analysis reveals the variation in the virtual reflection height of the equatorial nighttime lower ionosphere by using the magnetic field information contained in lightning sferics and discusses the possible reasons for this variation. Key Points: Variation in the nighttime lower ionospheric height near the equator is estimated with the measurement of low‐frequency lightning sfericsIonospheric reflection height at night in equatorial region shows significant temporal fluctuation, similar for peak reflection ratioEstimation of nighttime lower ionospheric height appears to considerably depend on the polarity of lightning strokes [ABSTRACT FROM AUTHOR]

We study the Cauchy problem for the three‐dimensional isentropic compressible Navier–Stokes/Allen–Cahn system, which models the phase transitions in two‐component patterns interacting with a compressible fluid. Under the assumption that the initial perturbation is small and decays spatially, we establish the global existence and the pointwise behavior of strong solutions to this nonconserved system. To deal with the source terms involving the phase variable, we employ the Green's function and space‐time weighted estimates. The analysis shows that the phase variable mainly contains the diffusion wave with exponential decaying amplitude over time, and consequently the density and momentum of the compressible fluid adhere to a generalized Huygens principle. [ABSTRACT FROM AUTHOR]

Highlights Polymer‐based composites that exhibit a unique nonlinear response to high‐power electric fields have the potential to serve as intelligent electromagnetic shielding materials. The optimization of switching fields (Eb) and nonlinear coefficient (α) of polymer‐based composites is of great interests for nonlinear conductive performance. Based on literature data, the prediction models for Eb and α are first successfully established using machine learning (ML) methods. A stacking ensemble learning (SEL) strategy was used to combine five base machine learning models, showing superior predictive performance. The research focuses on the effect of key process parameters on nonlinear conducting composites. The feature importance analysis shows that the nonlinear properties of the composites are considerably impacted by the mass fraction, filler size, and sample thickness. The parameter optimization method to improve the performance of the composites was explored by using partial dependence plots analysis. By measuring the nonlinear response of CNT/ZnO composites under high electric fields, the effectiveness of the optimization strategy is experimentally verified. This work establishes the intrinsic relationship between composition and performance, which is helpful in designing intelligent self‐adaptive electromagnetic shielding for switchable electronic devices. Prediction models for Eb and α using machine learning. Stacking ensemble learning for superior predictive performance Focuses on the effect of key process parameters on performance. Optimization strategy validated through experimental testing. [ABSTRACT FROM AUTHOR]

Long-term potentiation (LTP) in the Schaffer-CA1 region of the hippocampus is closely related to learning and memory. Magnetic stimulation, as an effective physical means of regulating synaptic plasticity, has received widespread attention. However, research on the mechanism of the effect of different frequencies of magnetic fields (MFs) on LTP is relatively scarce. This article focuses on Ca2+, Na+, K+, NMDA receptors, and AMPA receptors that play important roles in the process of MF regulation of LTP. A combined electrophysiological and pharmacological approach was used to identify Ca2+ as a key factor in the modulation of LTP by MFs of different frequencies. Subsequently, further experiments revealed that low levels of intracellular Ca2+ concentration ([Ca2+]i) intensified the inhibition of low-frequency MFs on LTP, while high levels of [Ca2+]i enhanced the promotion effect of high-frequency MFs on LTP, indicating a positive correlation between [Ca2+]i levels and MF regulation of LTP levels. The research results of this article may help explore the deeper relationship between different frequencies of MFs and synaptic plasticity, and they also have a certain reference value for magnetic stimulation therapy in the treatment of neurological diseases related to LTP injury or learning and memory deficits. [ABSTRACT FROM AUTHOR]

The stability of Zinc metal anodes (ZMAs) significantly limits the electrochemical performance and practical application of aqueous Zn‐ion batteries (ZIBs). An efficient and economical solution is the use of trace additives. However, efforts on trace additives are sparse, and essential uncertainties remain concerning their role in the stabilization of ZMAs. Herein, a low‐cost ZnSO4‐based aqueous electrolyte containing trace amounts of Acesulfame‐K (AK) (only 1.0 mg mL−1) is reported, which effectively suppresses the parasitic reactions occurring on the ZMA surface to realize a dendrite‐free Zn2+ deposition process, an ultra‐long cycle life over 1600 h and a high Coulombic efficiency of 99.86%. Accordingly, the practical Zn//NH4V4O10 full cell with AK also exhibits a high discharge capacity and capacity retention. In situ spectroscopies coupled with theoretical calculations reveal that the trace AK tends to accumulate at the ZMA/electrolyte interface to alleviate electrolyte corrosion. More importantly, the adsorbed AK can regulate the interfacial H2O structures (i.e., disrupting the interfacial H‐bonds to form more isolated H2O) to reduce the proton/hydroxides transport, thus suppressing the parasitic hydrogen evolution reaction and improving low‐temperature acclimation. This study provides design inspiration for trace additives expected to enable low‐cost and practical ZIBs with long lifespans. [ABSTRACT FROM AUTHOR]

Titanium alloy is widely used as oil drill pipe material because of its light weight, high strength, good toughness, corrosion resistance, fatigue resistance, and good process performance. However, due to its low hardness, poor wear resistance, serious oxidation at high temperature (700 °C), and difficulty in lubrication, in oil and gas field exploration and development drilling, especially in deep wells, high displacement wells, horizontal wells, and highly deviated wells, wear and tear are prone to occur. The application and development of titanium alloys are greatly limited. This paper introduces the research status of the common surface modification technologies of titanium alloys, such as laser cladding, magnetron sputtering, plasma spraying, micro arc oxidation, etc. It points out the improvement effect of various modification technologies on the wear resistance and high-temperature oxidation resistance of titanium alloys and discusses the advantages and disadvantages of various modification technologies. A proposed method for enhancing the wear resistance and high-temperature oxidation resistance of titanium alloys was finally introduced, and its potential for future development was investigated. [ABSTRACT FROM AUTHOR]

The lack of periosteum in bone allografts is considered a major cause of bone graft failure; however, the currently used artificial periosteum has failed to proactively adapt to its chronological role in the repair process. This study designed an adaptive periosteal system with dual‐response mechanisms to enable interactive angiogenic/osteogenic stimulation customized for inflammatory and anabolic stages of bone healing. Utilizing the enzymatic reactions and photodynamic properties of gold nanorod‐porous silicon, angiogenic peptides (QK) are released in response to matrix metalloproteinase 2 (MMP‐2), whereas bone‐forming peptides (BFP) are triggered by timed near‐infrared (NIR) irradiation, providing a portfolio of growth factors that match the dynamics of bone healing. The incorporation of such nanocarriers into a poly(N‐isopropyl acrylamide)/methacrylic acid gel (PNIPAM/GelMA) successfully formed a bionic periosteum that actively adapted to the function of the periosteum in different scenarios, resulting in more than doubled its ability to promote angiogenesis, stem cell migration, and osteogenesis compared to the controls. Furthermore, over 80% of the defects are covered with a new scab after the timed near‐infrared irradiation of large bone defects implanted with the system. The bionic periosteum actively mimicked the role of the periosteum in bone healing and offered a novel selection strategy for adaptability. [ABSTRACT FROM AUTHOR]

The substantial promotion of hydrogen evolution reaction (HER) catalytic performance relies on the breakup of the Sabatier principle, which can be achieved by the alternation of the support and electronic metal support interaction (EMSI) is noticed. Due to the utilization of tungsten disulfides as support for platinum (Pt@WS2), surprisingly, Pt@WS2 demands only 31 mV overpotential to attain 10 mA cm−2 in acidic HER test, corresponding to a 2.5‐fold higher mass activity than benchmarked Pt/C. The pH dependent electrochemical measurements associated with H2‐TPD and in situ Raman spectroscopy indicate a hydrogen spillover involved HER mechanism is confirmed. The WS2 support triggers a higher hydrogen binding strength for Pt leading to the increment in hydrogen concentration at Pt sites proved by upshifted d band center as well as lower Gibbs free energy of hydrogen, favourable for hydrogen spillover. Besides, the WS2 shows a comparably lower effect on Gibbs free energy for different Pt layers (−0.50 eV layer−1) than carbon black (−0.88 eV layer−1) contributing to a better Pt utilization. Also, the theoretical calculation suggests the hydrogen spillover occurs on the 3rd Pt layer in Pt@WS2; moreover, the energy barrier is lowered with increment in hydrogen coverage on Pt. Therefore, the boosted HER activity attributes to the EMSI effect caused hydrogen spillover and enhancement in Pt utilization efficiency. [ABSTRACT FROM AUTHOR]

The faradaic efficiency of Bi 2 WO 6 is 62.0% at -0.3 V vs. RHE, an improvement of 1.4- and 1.8-times relative to Bi 2 O 3 and WO 3 for the nitrate reduction reaction. In addition, the catalysis occurring on Bi 2 WO 6 follows the pathway: *NO 3 -*NO 2 -*NO-*NOH-*HNOH-*H 2 NOH-*NH 3 , as verified by operando Raman spectroscopy and theoretical calculations.

CoO/Fe 3 O 4 nanosheets exhibit a superior rechargeable zinc-air battery (ZAB) performance of 276 mW cm -2 and stability over 600 h. The all-solid-state ZAB also affords a high power density of 107 mW cm -2 .