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The non-noble metal (Fe, Co, Ni, etc.) catalysts possess promising potential to replace noble metals (e.g., Pt, Ru, Ir, etc.) as catalysts for oxygen electrocatalysis. Up to now, various mono- and dual-single-atom catalysts have been fabricated, though it is still challenging to synthesise ternary single-atom catalysts due to the difference of interaction forces between different metal ions (Fe, Co, Ni, etc.) and ligands. Here, we report a Fe-Co-Ni ternary single-atom catalyst (FeCoNi-Nx) derived from a zeolitic imidazolate frameworks (ZIF) precursor as an efficient oxygen electrocatalyst, and an optimised flexible casting-drying polyvinyl alcohol (CD-PVA) film as a quasi-solid electrolyte host, for high-efficiency solid-state Zn-air batteries. The aberration-corrected HAADF-STEM and EELS spectrum confirm the co-existence of Fe, Co and Ni single atoms in the FeCoNi-Nx catalyst, and the electrochemical, mechanical, and durability tests prove the superiority of the CD-PVA film. As a result, the FeCoNi-Nx-based rechargeable Zn-air battery delivers superior specific capacity (846.8 mAh·gZn–1) and power density (135 mW·cm–2) in aqueous electrolyte, as well as an over 60 mW·cm–2 power density in quasi-solid electrolyte. As a result, the quasi-solid-state Zn-air battery with a small area of only 2 cm2 is able to charge a mobile phone, which outperforms all the reported devices to date.

Abstract The development of the electric vehicle industry has spurred demand for secondary batteries capable of rapid‐charging and slow‐discharging. Among them, sodium‐ion batteries (SIBs) with layered oxide as the cathode exhibit competitive advantages due to their comprehensive electrochemical performance. However, to meet the requirements of rapid‐charging and slow‐discharging scenarios, it is necessary to further enhance the rate performance of the cathode material to achieve symmetrical capacity at different rates. Simultaneously, minimizing lattice strain during asymmetric electrochemical processes is also significant in alleviating strain accumulation. In this study, the ordered distribution of transition metal layers and the diffusion pathway of sodium ions are optimized through targeted K‐doping of sodium layers, leading to a reduction of the diffusion barrier and endowment of prominent rate performance. At a 20C rate, the capacity of the cathode can reach 94% of that at a 0.1C rate. Additionally, the rivet effect of the sodium layers resulted in a global volume strain of only 0.03% for the modified cathode during charging at a 10C rate and discharging at a 1C rate. In summary, high‐performance SIBs, with promising prospects for rapid‐charging and slow‐discharging capability, are obtained through the regulation of sodium layers, opening up new avenues for commercial applications.

Lithium-rich layered oxides (LROs) are considered as promising cathodes in building next-generation lithium-ion batteries (LIBs) with superior charge-discharge capacity. Nevertheless, LROs are confronted with irreversible oxygen loss accompanied with surface-to-bulk degradation upon cycling. To inhibit the oxygen release and to increase the lifespan of LROs, we report on an innovative strategy to rapidly construct an ultrathin oxygen-deficient shell layer covering the surface of LROs’ particles via a sparking plasma sintering (SPS) technique. It is demonstrated that the inner structure of the LROs’ particles is maintained, whereas the surface of the particles forms a thin shell (∼5 nm) consisting of a considerable amount of oxygen vacancies. Benefitting from the existence of an oxygen-deficient shell, the cathode activation is facilitated and the oxygen loss is suppressed, leading to enhanced capacity and prominent cyclability under long cycling. The modified LRO exhibits outstanding electrochemical performance, delivering a maximum capacity of 187.67 mAh g−1 and a capacity retention of 95.71% after 200 cycles at 250 mA g−1. Our work evidences that SPS is a fast and effective approach to construct oxygen-deficient shell on LRO cathodes for high-performance LIBs.

Abstract Extreme fast charging of Ampere-hour (Ah)-scale electrochemical energy storage devices targeting charging times of less than 10 minutes are desired to increase widespread adoption. However, this metric is difficult to achieve in conventional Li-ion batteries due to their inherent reaction mechanism and safety hazards at high current densities. In this work, we report 1 Ah soft-package potassium-ion hybrid supercapacitors (PIHCs), which combine the merits of high-energy density of battery-type negative electrodes and high-power density of capacitor-type positive electrodes. The PIHC consists of a defect-rich, high specific surface area N-doped carbon nanotube-based positive electrode, MnO quantum dots inlaid spacing-expanded carbon nanotube-based negative electrode, carbonate-based non-aqueous electrolyte, and a binder- and current collector-free cell design. Through the optimization of the cell configuration, electrodes, and electrolyte, the full cells (1 Ah) exhibit a cell voltage up to 4.8 V, high full-cell level specific energy of 140 Wh kg−1 (based on the whole mass of device) with a full charge of 6 minutes. An 88% capacity retention after 200 cycles at 10 C (10 A) and a voltage retention of 99% at 25 ± 1 °C are also demonstrated.

The common design methods for axial bearing capacity of driven piles in sand include conventional API method and four CPT-based methods, namely ICP-05, UWA-05, Fugro-05, and NGI-05. However, the reliability and accuracy of these design methods are still unclear, mainly owning to the lack of high-quality static load test data that can be used to evaluate the performance of these methods. High-quality database is also useful in the verification of any new design method. A new ZJU-ICL sand database consisting of 118 high-quality static load tests was established by expanding some commonly used databases by adding new test data. The database assessment of five design methods for axial bearing capacity of driven piles in sand was performed by using statistical method.

Defect modulation and understanding its impact on electrode materials remain challenging. Here, authors introduce twin boundaries into spinel cathode and demonstrate that their presence enables fast lithium ion diffusion.

Tannin, an antinutritional component of plant proteins was fed to grass carp (Ctenopharyngodon idellus, 8. 18 ± 0.81 g) for 8 weeks to investigate their tolerance levels. Semi-purified diets (T0, T1, T2, and T3) with varying levels of hydrolysable tannin (0, 0.75, 1.25, and 1.75% respectively) were used. No significant difference was obtained in weight gain, while feed conversion ratio of T0 was significantly lower than T2. Muscle protein content of T0 and T3 were significantly higher than T2, while lipid content of T0 was significantly higher than other groups. Muscle and hepatic glycogen in T0 were significantly lower than other groups. Muscle saturated fatty acids in T3 were significantly higher than T0, and lowest in T1 and T2, while the poly-unsaturated fatty acids in T1 and T2 were higher than T0 and lowest in T3. Significant increases were obtained in trypsin and amylase activities as tannin levels increased, the lipase activity of T0 and T1 was significantly higher than T2 and T3. Activities of hepatic alanine aminotransferase and aspartate aminotransferase decreased with increasing tannin level. The total protein in serum of T2 was significantly higher than T0 and T1 and lowest in T3, whereas globulin of T2 was significantly higher than T0 and T3 and lowest in T1, while albumin of T1 was significantly higher than other groups. Urea nitrogen of T0 was significantly higher than other groups, triglyceride and total cholesterol significantly increased with tannin level and decreased in T3, significant decreases were obtained in low-density lipoprotein cholesterol and high-density lipoprotein cholesterol in T3. mRNA expression of intestinal TOR was significantly upregulated as dietary tannin increased. In hepatopancreas, the expression of glucokinase in T1 was significantly higher than T2, and lowest in T0 and T3, pyruvate kinase in T2 was significantly higher than T0 and T1 and lowest T3. The expression of lipoprotein lipase upregulated as tannin level and downregulated in T3, and fatty acid synthase downregulated as tannin level. In conclusion, grass carp could tolerate 1.75% dietary tannin without influencing growth. However, 1.25% tannin impaired digestion and metabolism of protein, decreased the deposition of lipid and promoted utilization of carbohydrate.

Grass carp (Ctenopharyngodon idellus; n = 320) were received four different diets for 56 days. The experimental diets were: fishmeal (FM) containing 10% fishmeal (without rapeseed meal), and rapeseed meal (RM) containing 50% rapeseed meal (without fishmeal), and two semi-purified diets either without (T0) or with 1.25% (T1) supplemental hydrolysable tannin. The approximate content of tannin in the RM diet was 1.31%, which was close to that of T1, while the tannin content of FM was close to that of T0. The weight gain rate of grass carp of the RM group was significantly lower than that of the FM group, while the feeding conversion ratio and the feeding rate were significantly higher in the T1 group than in T0. The muscle lipid content was significantly lower in RM than in FM, while T1 was lower than T0. Intestinal activities of trypsin and α-amylase were significantly higher in T1 and RM groups compared with the other treatments. The hepatic activities of aspartate aminotransferase and alanine aminotransferase were lower in T1 and RM groups compared with the other treatments, while hepatic glycogen, and malonaldehyde were significantly higher in T1 and RM groups. In serum, the total protein and globulin contents were significantly higher in T1 and RM groups, while albumin was significantly lower in the RM group compared to the FM group. High-throughput sequencing showed that Proteobacteria, Firmicutes, and Actinobacteria were the dominant bacterial phyla among groups. The intestinal microbial diversity was higher in T1 and RM. Redundancy analysis showed that tannin, rapeseed meal, and intestinal trypsin activity were positively or negatively correlated with the relative abundance of several different intestinal microbiota at phylum and/or genus levels. The results indicated that 1.25% tannin could not be the main reason for the poor growth of grass carp of the RM group; however, the protein metabolism was disturbed, the absorption of carbohydrate was improved, and the accumulation of lipid had decreased. Furthermore, tannin and rapeseed meal supplementations modulated the intestinal microbiota, and may sequentially regulate the intestinal function by fermenting dietary nutrition, producing digestive enzymes, and modulating probiotics.

With the advent of intelligence technologies, more and more machines and devices are involved in the creation of complex structures. In the intelligent manufacturing industries, mouldings including injection moulding, blow moulding, compression moulding, and others play critical roles in manufacturing highly precise parts required for building intelligent machines (such as computers, cell phones, robots etc.). The performance of the clamping mechanism directly affects the quality of the microstructure of injection products. The design of the injection moulding mould clamping mechanism is based on the microstructure characteristics of the trip of the toggle lever mechanism ratio, speed ratio, and force amplification ratio. These are used to study the main performance parameters, such as analysis, as well as for the establishment of the physical model of the clamping mechanism. The model is based on the microstructure of injection of hyperbolic elbow clamping mechanism kinematics simulation. Simulation results and theoretical calculation contrast analysis show that the maximum dynamic template speed is 215.34 mm/s. The dynamic templates and cross-head speed ratio is 2.15; therefore, the design of the injection moulding mould clamping mechanism for the microstructure provides favourable technical support. The method described here is important to build complicated moulds required to build highly precise parts to build intelligent machineries.

Herein, the authors review the self-regulation system secured by well-designed hybrid materials, composites, and complex system. As a broad concept, the self-regulated material/system has been defined in a wide research field and proven to be of great interest for use in a biomedical system, mechanical system, physical system, as the fact of something such as an organisation regulating itself without intervention from external perturbation. Here, they focus on the most recent discoveries of self-regulation phenomenon and progress in utilising the self-regulation design. This paper concludes by examining various practical applications of the remarkable materials and systems including manipulation of the oil/water interface, cell out-layer structure, radical activity, electron energy level, and mechanical structure of nanomaterials. From material science to bioengineering, self-regulation proves to be not only viable, but increasingly useful in many applications. As part of intelligent engineering, self-regulatory materials are expected to be more used as integrated intelligent components.