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In order to investigate the change in proline metabolism of two varieties of Hami melon fruits during low-temperature storage, ‘Xizhoumi 25’ and ‘Gashi’ melons were pre-cooled for 24 h and then placed for up to 42 days in a mechanical cold storage at (3.0 ± 0.5) ℃. Chilling injury symptoms were recorded, and chilling injury index, free proline content and proline metabolism-related indexes were measured every seven days . The results showed that the symptoms of chilling injury in ‘Gashi’ melon were significantly milder than those in ‘Xizhoumi 25’ melon, and as the storage time increased, free proline content, Δ1-pyrrolidine-5-carboxylic acid synthase (P5CS) activity, ornithine transaminase (OAT) activity and their relative gene expression increased significantly for both varieties; all these indicators were significantly higher in ‘Gashi’ melon than ‘Xizhoumi 25’ melon. The activity and relative gene expression of proline dehydrogenase (ProDH) decreased, indicating that both varieties of Hami melon fruits could resist chilling injury by increasing the free proline content and the activities of P5CS and OAT, the key enzymes for proline synthesis, and decreasing the activity of ProDH, the key enzyme for proline degradation. The metabolomics study revealed that the amino acid content of ‘Xizhoumi 25’melon decreased when the chilling injury became more serious, while the amino acid content of ‘Gashi’ melon showed an opposite trend. Whole gene synthesis of CmP5CS, a key enzyme gene involved in the proline metabolic pathway of Hami melon fruits, revealed that the Hami melon CmP5CS gene had the closest relatedness to melon (LOC103485529) P5CS, indicating functional similarity between them.

Aqueous Zn-ion hybrid supercapacitors (AZHSCs) combining the advantages of high‐energy batteries and high‐power supercapacitors see a bright future, but they still suffer from the poor capacity of carbonic cathodes. Herein, a functionalized porous carbon cloth (denoted as FPCC) electrode is demonstrated based on commercial carbon cloth (denoted as CC) tuning by structural and surface engineering. The constructed exfoliated porous carbon layer and the negatively charged functionalized interface not only increase the electrical double layer capacitance but also favor the chemical adsorption of Zn2+ to obtain additional pseudocapacitance. Consequently, the FPCC electrode delivers a high capacity of 0.16 mAh cm−2 at 4 mA cm−2, which is 923.8 times higher than CC, and a long cycle life (85.0% capacity retention after 30 000 cycles). More importantly, the Zn//FPCC AZHSC possesses an impressive energy density (3.3 mWh cm−3) and power density (240 mW cm−3), superior to many advanced batteries and supercapacitors. The quasi-solid-state device is also assembled as a demo. This modification strategy may provide new opportunities for high-performance AZHSCs. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) are emerging as one of the most reliable energy storage technologies for scale‐up applications, but still suffer from the instability of Zn anode, which is mainly caused by the undesirable dendrite growth and side reactions. To tackle these issues, we formulate a new aqueous electrolyte with weak solvation effect by introducing low‐dielectric‐constant acetone to achieve H2O‐poor solvation structure of Zn2+. Experimental and theoretical calculation studies concurrently reveal that such solvation structure can: i) relieve the solvated H2O related side reactions, ii) suppress the dendrite growth by boosting the desolvation kinetics of Zn2+ and iii) in situ form solid electrolyte interface (SEI) to synergistically inhibit the side reaction and dendrite growth. The synergy of these three factors prolongs the cycling life of Cu/Zn asymmetric cell from 30 h to more than 800 h at 1 mA cm−2/1 mAh cm−2, and can work at more harsh condition of 5 mA cm−2/5 mAh cm−2. More encouragingly, Zn/V2O5 ⋅ nH2O full cell also shows enhanced cycling stability of 95.9 % capacity retention after 1000 cycles, much better than that with baseline electrolyte (failing at ≈700th cycle). [ABSTRACT FROM AUTHOR]

The inferior capacity and cyclic durability of V2O5 caused by inadequate active sites and sluggish kinetics are the main problems to encumber the widespread industrial applications of vanadium‐zinc batteries (VZBs). Herein, a cooperative redox chemistry (CRC) as "electron carrier" is proposed to facilitate the electron‐transfer by capturing/providing electrons for the redox of V2O5. The increased oxygen vacancies in V2O5 provoked in situ by CRC offers numerous Zn2+ storage sites and ion‐diffusion paths and reduces the electrostatic interactions between vanadium‐based cathode and intercalated Zn2+, which enhance Zn2+ storage capability and structural stability. The feasibility of this strategy is fully verified by some CRCs. Noticeably, VZB with [Fe(CN)6]3−/[Fe(CN)6]4− as CRC displays conspicuous specific capacity (433.3 mAh g−1), ≈100% coulombic efficiency and superb cyclability (≈3500 cycles without capacity attenuation). Also, the mechanism and selection criteria of CRC are specifically unraveled in this work, which provides insightful perspectives for the development of high‐efficiency energy‐storage devices. [ABSTRACT FROM AUTHOR]