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As a new type of secondary ion battery, aqueous zinc‐ion battery has a broad application prospect in the field of large‐scale energy storage due to its characteristics of low cost, high safety, environmental friendliness, and high‐power density. In recent years, manganese dioxide (MnO2)‐based materials have been extensively explored as cathodes for Zn‐ion batteries. Based on the research experiences of our group in the field of aqueous zinc ion batteries and combining with the latest literature of system, we systematically summarize the research progress of Zn−MnO2 batteries. This article first reviews the current research progress and reaction mechanism of Zn−MnO2 batteries, and then respectively expounds the optimization of MnO2 cathode, Zn anodes, and diverse electrolytes and their effects on battery performance. Additionally, primary challenges related to different components and their respective strategies for mitigating them are discussed, with the ultimate objective of offering comprehensive guidance for the design and fabrication of high‐performance Zn−MnO2 batteries. Finally, the future research and development direction of aqueous Zn−MnO2 batteries with high energy density, high safety and long life is envisioned. [ABSTRACT FROM AUTHOR]

Silver‐zinc (Ag–Zn) batteries are a promising battery system for flexible electronics owing to their high safety, high energy density, and stable output voltage. However, poor cycling performance, low areal capacity, and inferior flexibility limit the practical application of Ag–Zn batteries. Herein, we develop a flexible quasi‐solid‐state Ag–Zn battery system with superior performance by using mild electrolyte and binder‐free electrodes. Copper foam current collector is introduced to impede the growth of Zn dendrite, and the structure of Ag cathode is engineered by electrodeposition and chloridization process to improve the areal capacity. This novel battery demonstrates a remarkable cycle retention of 90% for 200 cycles at 3 mA cm−2. More importantly, this binder‐free battery can afford a high capacity of 3.5 mAh cm−2 at 3 mA cm−2, an outstanding power density of 2.42 mW cm−2, and a maximum energy density of 3.4 mWh cm−2. An energy management circuit is adopted to boost the output voltage of a single battery, which can power electronic ink display and Bluetooth temperature and humidity sensor. The developed battery can even operate under the extreme conditions, such as being bent and sealed in solid ice. This work offers a path for designing electrodes and electrolyte toward high‐performance flexible Ag–Zn batteries. [ABSTRACT FROM AUTHOR]

Converting degraded croplands into perennials has been proposed as an effective method of soil N sequestration, however, the dynamics of deep soil N (>100 cm) following cropland conversion are not well understood. In this study, we synthesized 3049 observations to detect the changes in deep soil N content following cropland conversion on the arid and semiarid Loess Plateau. Our results showed that converting croplands into perennials significantly increased the soil N content by an average of 57.4%, 23.1%, and 29.5% in the surface (0–20 cm), subsurface (20–100 cm), and deep (100–200 cm) layers, respectively. The extent of the increase was influenced significantly by the land‐use conversion types and tree species. Specifically, the conversion of croplands into deep‐rooted forests or shrubs, particularly Robinia pseudoacacia and Caragana microphylla, exhibited higher advantages in deep soil N sequestration. Moreover, deep soil N sequestration increased significantly with time since cropland conversion (p < 0.001), and the rates in deep soils were approximately 26.1% and 66.7% of that in 0–20 and 20–100 cm soils, respectively. In the long term, converting croplands into forests and shrubs showed higher potential for deep soil N sequestration. Linear regression analysis showed that the changes of deep soil N sequestration were influenced significantly by initial soil N content (p < 0.001) and humidity index (p < 0.001), with the slopes in >100 cm layers being 2 to 3 times than that in the top meter, indicating higher sensitivity in deep soils. Overall, this study provides evidence that converting degraded croplands into perennials may contribute to deep soil N accumulation in N‐limited regions, which could potentially alleviate N limitation and sustain long‐term ecosystem carbon sequestration. [ABSTRACT FROM AUTHOR]

Waterborne epoxy resins have been extensively applied to industries as green paints. However, waterborne epoxy resins are affected by several issues. To enhance their mechanical properties and corrosion resistance, we added nanotitanium‐based hybrid materials (NTH), and methyl methacrylate (MMA)/nitrile rubber (NBR)/graphene oxide (GO) to waterborne epoxy resin. The researchers suggest that adding NTH and MMA/NBR/GO can well modify waterborne epoxy resin. Upon addition of 6 wt.% NTH and 1 wt.% MMA/NBR/GO (2‐1 coating), scanning electron microscopy imaging shows that the coating is flat, with no evident crevices. Fourier‐transform infrared spectroscopy results indicate that compared with the case in which either NTH or MMA/NBR/GO is added, the coating is denser when both fillers are added. The mechanical properties were also investigated, and the results demonstrate that the coating displayed a pencil hardness rating of "2H" and achieved a grade of "0" in terms of adhesion, respectively. Additionally, the coating's anticorrosion performance was evaluated through electrochemical tests. Tafel tests and electrochemical impedance spectroscopy tests reveal that the 2‐1 coating possesses superior corrosion resistance with respect to the other coatings. Additionally, after a neutral salt spray test lasting 1440 h, the surface of the coating showed no signs of corrosion according to salt spray tests. Finally, the anticorrosion mechanism is discussed. [ABSTRACT FROM AUTHOR]

The gut microbiota, a complex ecosystem integral to host wellbeing, is modulated by environmental triggers, including exposure to heavy metals such as chromium. This study aims to comprehensively explore chromium-induced gut microbiota and metabolomic shifts in the quintessential lepidopteran model organism, the silkworm (Bombyx mori). The research deployed 16S rDNA sequence analysis and LC/MS metabolomics in its experimental design, encompassing a control group alongside low (12 g/kg) and high (24 g/kg) feeding chromium dosing regimens. Considerable heterogeneity in microbial diversity resulted between groups. Weissella emerged as potentially resilient to chromium stress, while elevated Propionibacterium was noted in the high chromium treatment group. Differential analysis tools LEfSe and random forest estimation identified key species like like Cupriavidus and unspecified Myxococcales, offering potential avenues for bioremediation. An examination of gut functionality revealed alterations in the KEGG pathways correlated with biosynthesis and degradation, suggesting an adaptive metabolic response to chromium-mediated stress. Further results indicated consequential fallout in the context of metabolomic alterations. These included an uptick in histidine and dihydropyrimidine levels under moderate-dose exposure and a surge of gentisic acid with high-dose chromium exposure. These are critical players in diverse biological processes ranging from energy metabolism and stress response to immune regulation and antioxidative mechanisms. Correlative analyses between bacterial abundance and metabolites mapped noteworthy relationships between marker bacterial species, such as Weissella and Pelomonas, and specific metabolites, emphasizing their roles in enzyme regulation, synaptic processes, and lipid metabolism. Probiotic bacteria showed robust correlations with metabolites implicated in stress response, lipid metabolism, and antioxidant processes. Our study reaffirms the intricate ties between gut microbiota and metabolite profiles and decodes some systemic adaptations under heavy-metal stress. It provides valuable insights into ecological and toxicological aspects of chromium exposure that can potentially influence silkworm resilience. [ABSTRACT FROM AUTHOR]

To enhance the anti‐corrosion of the waterborne epoxy resin coating, we filled GO‐TiO2 into the coating with ultrasound and stirring method. Results show that coatings rendered optimum properties at GO‐TiO2 content of 0.4 wt% with a hardness of 3H and rate of thermal weight loss reduce 8.3 wt%. After immersion for 30 days, coating exhibited water absorption ratio of merely 11.25% and open circuit potential of −0.871 V. After 1000 h of scratch‐neutral salt spray test, no obvious signs of corrosion were observed on surface. Moreover, Electrochemical results demonstrated that maximum impedance modulus of 0.4GO‐TiO2 coating was 2.18 × 106 Ω cm2, corresponding to superior corrosion resistance. What is more, anticorrosion mechanism was discussed. In conclusion, Filling GO‐TiO2 improved mechanical properties, thermal stability and corrosion resistance of waterborne epoxy resin coatings. [ABSTRACT FROM AUTHOR]

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