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The fabric‐based pneumatic exosuit is now a hot research topic because it is lighter and softer than traditional exoskeletons. Existing research focuses more on the mechanical properties of the exosuit (e.g., torque and speed), but less on its wearability (e.g., appearance and comfort). This work presents a new design concept for fabric‐based pneumatic exosuits: volume transfer, which means transferring the volume of pneumatic actuators beyond the garment's profile to the inside. This allows for a concealed appearance and a larger stress area while maintaining adequate torques. In order to verify this concept, a fabric‐based pneumatic exosuit is developed for knee extension assistance. Its profile is only 26 mm and its stress area wraps around almost half of the leg. A mathematical model and simulation is used to determine the parameters of the exosuit, avoiding multiple iterations of the prototype. Experiment results show that the exosuit can generate a torque of 7.6 Nm at a pressure of 90 kPa and produce a significant reduction in the electromyography activity of the knee extensor muscles. It is believed that volume transfer can be utilized prevalently in future fabric‐based pneumatic exosuit designs to achieve a significant improvement in wearability. [ABSTRACT FROM AUTHOR]

It is an increasingly mature application solution that triboelectric nanogenerator (TENG) supplies power to electronic devices through its power management system (PMS). However, the previous PMS is able to manage a limited voltage magnitude and the energy storage elements are limited to capacitors. This work proposes an ultrahigh voltage PMS (UV‐PMS) to realize the charging of commercial lithium cells (LCs) by TENG. The design of UV‐PMS enables energy management of TENGs with ultrahigh open‐circuit voltages up to 3500 V and boosts the peak charging current from 30.9 µA to 2.77 mA, an increase of 89.64 times. With the introduction of UV‐PMS, the effective charging capacity of LC charged by a TENG at a working frequency of 1.5 Hz for 1 h comes to 429.7 µAh, making a 75.3 times enhancement compared to charging by TENG directly. The maximum charging power comes to 1.56 mW. The energy storage efficiency is above 97% and the overall charge efficiency can be maintained at 81.2%. This work provides a reliable strategy for TENG to store energy in LC, and has promising applications in energy storage, LC's life, and self‐powered systems. [ABSTRACT FROM AUTHOR]

The metal–insulator transition (MIT) of vanadium dioxide (VO2), which involves significant changes in electrical, optical, and other properties, has attracted widespread attention. Here, we report a triboelectric nanogenerator (TENG)-based self-powered VO2 phase transition. With the TENG-induced ionic gel gating, the hydrogen ion insertion/detachment in the VO2 lattice can be modulated at room temperature to cause phase transitions that control light transmittance. The phase transition behavior is characterized by X-ray diffraction and Raman spectroscopy. Under the continuous power supply from TENG, the X-ray diffraction peak of VO2 shifts, and the Raman intensities of characteristic peaks decrease, accompanied by a color change from brown to translucent. The electrical conductivity undergoes a significant change by two orders of magnitude and persists overnight, indicating an excellent duration of the phase transition. In addition, a raindrop TENG-induced VO2 phase transition is demonstrated. The infrared transmittance of VO2 is decreased dramatically by 28.1% due to the phase transition, achieving a heat preservation effect that holds promise for adaptive thermal insulation in smart windows during rainfall through raindrop power generation. This work has realized the TENG-based self-powered VO2 phase transition, holding significant application potential in smart homes. [ABSTRACT FROM AUTHOR]

Since the initial impoundment and commissioning of the Three Gorges Reservoir in June 2003, seismic activity surrounding the reservoir region has undergone substantial changes. Leveraging geological and hydrogeological data from the Three Gorges Reservoir area, this study statistically analyzes the historical water level and earthquake catalog within the reservoir. By examining the correlation between reservoir water levels and earthquake frequency, the relationship between seismicity along the Xiannvshan fault and water level is analyzed. Additionally, the ArcGIS software is employed to evaluate the spatial pattern of earthquake epicenters during the filling of the Three Gorges Reservoir, with the goal of elucidating the impact of water impoundment at the Three Gorges on the activity along the Xiannvshan fault. The results demonstrate the following. (1) There is a complex process of “continuous loading, permeation and saturation, rebound and rebalancing” in the crust of the reservoir head area during the impoundment of the Three Gorges Reservoir area, and the activity of the Xiannvshan fault is closely related to the reservoir water level. (2) At the 135 m impoundment stage, Xiannvshan fault activity is mainly affected by reservoir water level and is positively correlated with reservoir water level. At the 156 m impoundment stage, reservoir water load is still the main influencing factor of Xiannvshan fault activity, but the permeability of reservoir water is enhanced in this stage. (3) The earthquake epicenters near the northern section of the Xiannvshan fault are clustered during the 175 m experimental impoundment stage. During the continuous loading stage, the reservoir water load is still the main control factor of the Xiannvshan fault, and the seismic activity is significantly enhanced. From November 2010 to November 2013, during the permeation and saturation stage, the dominant factor of Xiannvshan fault activity changed from reservoir water load to reservoir water infiltration along the Xiannvshan fault. The period from 2013.11 to 2014.5 was a vertical rebound stage, and the infiltration effect of reservoir water had a more significant impact on Xiannvshan fault activities.

The emerging tribovoltaic nanogenerators (TVNGs) has garnered considerable attention in recent years owing to its higher power density, but it is still limited by unstable output, mismatched impedance, and lower charging speed. Herein, a power‐managed GaN‐based TVNG is first proposed and a self‐powered wireless temperature monitoring system (SWTMS) is developed. The energy backflow from transition capacitor to TVNG is effectively suppressed by applying a high‐voltage‐resistant diode. Benefiting from the combination of the maximum power point tracking (MPPT and the buck converter, an autonomous power management unit (PMU) is designed. The internal impedance of TVNG with PMU decreases by ten times and the charging speed of capacitor increases by 7.18 times compared to those without PMU. Moreover, 100 LEDs and six parallel thermohygrometers can be constantly powered. The wireless temperature monitoring in industrial environments without external power supply is demonstrated through the developed SWTMS. This work proposes an effective power management strategy for TVNG with high output voltage, which exhibits great potential to promote the development of self‐powered sensors and Industrial Internet of Things (IIoT). [ABSTRACT FROM AUTHOR]

Garnet‐based solid electrolytes (SEs), which have both high ionic conductivity and great stability with Li metal anodes, are at the center of an ever‐increasing research effort in all‐solid‐state lithium metal batteries (ASSLMBs) toward high safety and high energy density. However, the performance of garnet‐based ASSLMBs is limited by the poor ionic conduction on the cathode side, mainly attributed to the inherent rigidity of oxide ceramic nature. Here, a sintering‐free strategy to boost the ionic conduction of the composite cathode via the use of a soft halide SE is presented. The inclusion of the cathode‐compatible halide SE facilitates efficient and stable Li+ conduction within the composite cathode and at the cathode/garnet pellet interface. Compared to the conventional co‐sintered method, the issues associated with element diffusion between solid particles during high‐temperature processes are circumvented, a factor responsible for the degradation and irreversible capacity reduction of the cathode active material. When combined with a lithium metal anode, the new cathode configuration exhibits decent discharge capacity, superior Coulombic efficiency, and enhanced cycle stability. The findings demonstrate the promise of this composite cathode design as a viable pathway for achieving high‐performance garnet‐based ASSLMBs. [ABSTRACT FROM AUTHOR]

The Three Gorges Hydropower Station, the largest in the world, plays a pivotal role in hydroelectric power generation, flood control, navigation, and ecological conservation. The water level of the Three Gorges Reservoir has a direct impact on these aspects. Accurate prediction of the reservoir's water level, especially in the dam area, is of utmost importance for downstream regions' safety and economic development. This study investigates the application and performance of four distinct deep-learning models in predicting water levels. The models evaluated include the Long Short-Term Memory (LSTM), Bidirectional Long Short-Term Memory (BiLSTM), Convolutional Neural Network–Long Short-Term Memory (CNN–LSTM), and Convolutional Neural Network–Attention–Long Short-Term Memory (CNN–Attention–LSTM). The performance of these models was assessed using several metrics, namely the Coefficient of Determination (R2), Mean Absolute Error (MAE), Root Mean Squared Error (RMSE), and Mean Absolute Percentage Error (MAPE). The findings indicate that the CNN–Attention–LSTM model outperforms the others in all metrics, achieving an R2 value of 0.9940, MAE of 0.5296, RMSE of 0.6748, and MAPE of 0.0032. Moreover, the CNN–LSTM model exhibited exceptional predictive accuracy for lower water levels. These results underscore the potential of deep-learning models in water-level forecasting, particularly highlighting the efficacy of attention mechanisms in enhancing predictive accuracy. Precise water-level predictions are instrumental in optimizing hydropower generation and providing a scientific basis for effective flood control and water resource management. [ABSTRACT FROM AUTHOR]

Taken the unlimited Na reservoir worldwide, battery technology based on Na-ion chemistry poses as an ideal candidate for large-scale energy storage systems. Especially, with metallic Na replacing traditional carbon anodes, it's able to maximize the energy density inexpensively. Nevertheless, sodium metal batteries (SMBs) face intrinsically poor stability due to their highly-reactive nature, where low Coulombic efficiency and short lifetime are often witnessed. The situation can be further aggravated at low temperatures due to insurmountable kinetic barriers. Herein, a 1,3-dioxolane-based quasi-solid-state electrolyte (PDGE) is proposed with a high ionic conductivity of3.68 mS cm-1 even at -20 °C for SMBs. Moreover, a weak solvation environment is tailored by PDGE, which possesses a high Na+ transference number of 0.7. Concurrently, the solid electrolyte interphase induced from PDGE presents inorganic Na2O, NaF as the major components, which offers accelerated Na+ diffusion and superior stability upon long-term cycling. With such a quasi-solid-state electrolyte, the Na/Na3V2(PO4)3 full cell exhibits great stability over 1000 cycles at -20 °C. This study has significant implications to the development for SMBs under low-temperature conditions. [ABSTRACT FROM AUTHOR]

Surface engineering of carbon materials induces structural modulation with appealing functionalities for versatile applications. However, practical deployment demands simplified modification steps and time-saving operations. Microwave technology can produce a strong instant magnetic-heating effect, avoiding the presence of a temperature gradient to cause nanoparticle agglomeration and multiple synthesis stages. Herein, we propose a rapid Joule carbothermal synthesis of a 3D flexible carbon cloth with ultrasmall metal oxide nanoparticles (MOx@CC) upon microwave irradiation within several minutes. Owing to the extensive selection of metal precursors, this approach can be applied to achieve a variety of active metal oxide nanoparticles decorated on carbon cloth. Furthermore, the modified carbon cloth can serve as a lithiophilic framework to efficiently homogenize Li+ flux and mitigate the dendrite formation. Ascribed to these merits, a prototype of the prelithiation MOx@CC anode paired with the LiFePO4 cathode exhibits satisfactory performance upon repetitive cycling, highlighting the possibility for a safe battery system. [ABSTRACT FROM AUTHOR]

Trimethylamine-N-oxide (TMAO), a diet-derived cometabolite linked to cardiometabolic disease, has been associated with elevated dietary status, particularly in people with kidney failure and adults with dietary modulations. However, the influence of the current diet on TMAO levels in free-living children has not been adequately described. This study was to explore associations of food compositions and dietary diversity with urinary TMAO and its precursor concentrations. Urinary TMAO and its precursor concentrations of 474 healthy children from the Sheyang Mini Birth Cohort were quantified by ultra-performance liquid chromatography–Q Exactive high-resolution mass spectrometer (UPLC-Q Exactive HRMS). Individual food compositions from 24 h dietary recall data were classified into 20 groups and diversity scores were calculated according to the guidelines of the Food and Agriculture Organization of the United Nations (FAO). Associations of urinary TMAO and its precursors with food compositions and dietary diversity scores were assessed by generalized linear regression models. In models adjusted for potential confounders, urinary TMAO was significantly associated with intakes of fish (β, regression coefficient = 0.155, p < 0.05) and vegetables (β = 0.120, p < 0.05). Eggs intake showed positive associations with TMAO's precursors (trimethylamine: β = 0.179, p < 0.05; choline: β = 0.181, p < 0.05). No association between meat intake and TMAO was observed, whereas meat and poultry intakes were related to the levels of acetyl-L-carnitine and L-carnitine (β: 0.134 to 0.293, p < 0.05). The indicators of dietary diversity were positively correlated to TMAO concentration (β: 0.027 to 0.091, p < 0.05). In this free-living children-based study, dietary factors were related to urinary TMAO and its precursors, especially fish, meat, and eggs. As such, dietary diversity was positively related to the level of TMAO. [ABSTRACT FROM AUTHOR]

Lithium metal anodes may allow the energy density limit of rechargeable lithium batteries to be pushed higher. However, simple and efficient processing technologies for thin Li metal are lacking, which has significantly limited its applications. Herein, the feasibility of engineering Li metal by compositing it with ferromagnetic particles (termed magnetic Li, abbr. M‐Li) is reported. Due to its magnetic response, straightforward processing of M‐Li on diverse substrates with customized patterns and desired thickness is realized. Moreover, when a garnet‐type solid‐state electrolyte Li6.5La3Zr1.5Ta0.5O12 (LLZTO) is the substrate, intimate contact between M‐Li and LLZTO is obtained, with a low interfacial resistance of ≈11 Ω cm2. In addition to facilitating movement and wetting on various substrates, magnetic transfer of M‐Li sheets to designated locations is also enabled. The intriguing and brand‐new method for Li metal engineering via magnetic actuation may be adopted by the industrial system for the fabrication of Li metal batteries, extended to other alkali metals and promises further progress. [ABSTRACT FROM AUTHOR]

Room‐temperature sodium metal batteries (SMBs) have gained tremendous interest owing to the cost‐efficiency and wide geographical availability of sodium, whereas severe safety issues have long handicapped their practical applications. Here a fire‐extinguishant‐implanted electrolyte (FEIE) is demonstrated where a nonpolar fluoroether simultaneously bonds the fluorinated carbonate‐based electrolyte and a sodium‐compatible extinguishant via its amphiphilicity. The as‐designed FEIE enables intrinsic safety and eliminates fire hazards. Furthermore, the FEIE‐induced inorganic‐enriched solid electrolyte interphase (SEI) dramatically improves the Na deposition, Coulombic efficiency (CE), and further offers the cycling stability for 1100 h at 10 mAh cm−2 in symmetric cells and 1000 cycles with a high average CE (99.8%) in full cells. Usage of the functional molecules possessing amphiphilicity extends the scope for applying immiscible agents in battery electrolytes. [ABSTRACT FROM AUTHOR]

Sodium metal batteries (SMBs) are promising for large scale energy storage due to the remarkable capacity of sodium metal anode (SMA) and the natural abundance of Na‐containing resources. However, multiple challenges exist with regards to the usage of SMBs, including dendritic Na growth, poor cyclability of SMA, and severe safety hazards stemming from the employment of the highly flammable liquid electrolytes. Herein, by introducing two functional fluorinated solvents, 1,1,2,2‐tetra‐fluoroethyl 2,2,3,3‐tetrafluoropropyl ether (HFE) and fluoroethylene carbonate (FEC) into trimethyl phosphate (TMP)‐based electrolyte, a SMA‐compatible flame‐retardant electrolyte is enabled, in which Na/Na symmetrical cells can cycle for 800 h at 1.0 mA cm−2 or 3.0 mAh cm−2. Specifically, the non‐solvating HFE plays a critical role in increasing the local electrolyte concentration and reducing the unfavorable decomposition of TMP molecules. By introducing FEC as the co‐solvent simultaneously, its preferential defluorination induces a fluoride‐rich solid‐electrolyte interphase that prevents Na metal surface against the continuous parasitic reactions. More importantly, the designed electrolyte is endowed with an intrinsic non‐flammability, which manifests a prerequisite for the real‐life application of SMBs. [ABSTRACT FROM AUTHOR]

The radiological toxicity of uranium in nuclear industrial wastewater poses a long-term threat to environment, thus the effective separation of radionuclide from wastewater is very important for environmental safety. Herein, the macroporous ion-imprinted chitosan foams (ICFs) were synthesized by the combination of the facile freezing-drying and ion-imprinting techniques. Compared with non-imprinted chitosan foam, the ICFs showed much higher adsorption capacities (q m = 248.9–253.6 mg/g) and better adsorption selectivity for U(VI) owing to their smart recognition of the target ions for matching the cavities formed during U(VI)-imprinting process. The adsorption kinetics could be fitted by pseudo-second-order model; whereas the adsorption isotherms could be described by Langmuir model, indicating chemisorption or complexation mechanism. The FT-IR and XPS analysis further confirms that the coordination between U(VI) and the active sites (amine and hydroxyl groups) is the main adsorption mechanism. The thermodynamic parameters suggest that the adsorption of U(VI) is endothermic and spontaneous. This work provides new insights for the design of novel macroporous biosorbents with both high adsorption capacity and excellent adsorption selectivity for U(VI) biosorption from wastewater. • The novel ion-imprinted macroporous chitosan foams (ICFs) was synthesized and characterized. • ICFs showed adsorption performance owing to their macroporous structure and smart recognition of U(VI). • The FT-IR and XPS analysis confirms that -NH 2 and -OH groups are the active sites for U(VI) adsorption. • The modeling of the adsorption kinetics and isotherms indicates chemisorption mechanism for U(VI) adsorption. [ABSTRACT FROM AUTHOR]