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Rechargeable lithium‐oxygen (Li‐O2) batteries with high theoretical energy density are regarded as a promising candidate for the booming electric vehicle manufacturing industry, whereas their commercial application is hindered due to poor cyclic stability caused by the sluggish kinetics and inevitable cathode passivation. Herein, a synergistic working mechanism of Li‐O2 battery is initiated by implementing well‐designed hollow carbon shells with hierarchically porous hollow structure (HCS) assisted by dual redox mediators (RMs) simultaneously, so as to systemically address issues of diminished discharge capacity and reaction kinetics. The hierarchically porous structure of HCS constructs more space to accommodate Li2O2, increases the accessibility of active sites, and enhances discharge capacity. More importantly, the dual RMs regulate the growth mechanism of Li2O2 in surface‐mediated mode, resulting in an easily decomposed film‐like Li2O2 with higher electron transport capacity and improving the reaction kinetics. As a result of the synergistic effort, an HCS‐based Li‐O2 battery with dual RMs manifests a total discharge capacity of 24580 mA h g−1 and a prolonged cycle life of 2500 h at the current density of 100 mA g−1. This design philosophy will open up a new way to optimize and upgrade the cathode materials of Li‐O2 batteries. [ABSTRACT FROM AUTHOR]

With the increase of waste lithium-ion batteries (WLIBs), the recycling of WLIBs has been paid more attention. Lithium metal battery (LMB) has extremely high theoretical specific capacity. However, the decline of cycle performance and the danger of short circuit caused by lithium dendrite formation and dead lithium accumulation are still the most thorny problems for the anode of LMB. Herein, the high value utilization of WLIBs anode graphite was explored, and it was prepared as a 3D frame material for LMB. Liquid-phase reduced graphite oxide nanosheets (lrGO) were prepared from AG, then, ZnO nanoparticles were loaded on lrGO. SEM, EDX and XRD were used to characterize lrGO and lrGO-ZnO , and the electrochemical tests were carried out. The results showed that lrGO and lrGO-ZnO maintained excellent cycle stability. Under the constant current density of 1mA cm-2, the stable cycle of lrGO-ZnO was 700 cycles, and the charge-discharge platform potential difference maintained at 22.5 mV after 200th cycle. The unique 3D structure of lrGO increased the electrode reaction area and suppressed the volume expansion of Li. The loading of ZnO significantly improved the lithiophilicity and cycle stability.

Although biomass‐derived carbon (biochar) has been widely used in the energy field, the relation between the carbonization condition and the physical/chemical property of the product remains elusive. Here, we revealed the carbonization condition's effect on the morphology, surface property, and electrochemical performance of the obtained carbon. An open slit pore structure with shower‐puff‐like nanoparticles can be obtained by finely tuning the carbonization temperature, and its unique pore structure and surface properties enable the Li–O2 battery with cycling longevity (221 cycles with 99.8% Coulombic efficiency at 0.2 mA cm−2 and controlled discharge–charge depths of 500 mAh g−1) and high capacity (16,334 mAh g−1 at 0.02 mA cm−2). This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions, paving the way for future study of energy storage devices. [ABSTRACT FROM AUTHOR]

The rational design of large‐area exposure, nonagglomeration, and long‐range dispersion of metal nanoparticles (NPs) in the catalysts is critical for the development of energy storage and conversion systems. Little attention has been focused on modulating and developing catalyst interface contact engineering between a carbon substrate and dispersed metal. Here, a highly dispersed ultrafine ruthenium (Ru) NP strategy by double spatial confinement is proposed, that is, incorporating directed growth of metal–organic framework crystals into a bacterial cellulose templating substrate to integrate their respective merits as an excellent electrocatalytic cathode catalyst for a quasi‐solid‐state Li–O2 battery. The porous carbon matrix with highly dispersed ultrafine Ru NPs is well designed and used as cathode catalysts in a Li–O2 battery, demonstrating a high discharge areal capacity of 6.82 mAh cm–2 at 0.02 mA cm–2, a high‐rate capability of 4.93 mAh cm–2 at 0.2 mA cm–2, and stable discharge/charge cycling for up to 500 cycles (2000 h) with low overpotentials of ~1.4 V. This fundamental understanding of the structure–performance relationship demonstrates a new and promising approach to optimize highly efficient cathode catalysts for solid‐state Li–O2 batteries. [ABSTRACT FROM AUTHOR]

This paper studies a generalized distributed optimization problem for second-order multi-agent systems (MASs) over directed networks. Firstly, an improved distributed continuous-time algorithm is proposed. By using the linear transformation method and Lyapunov stability theory, some conditions are obtained to guarantee all agents' states asymptotically reach the optimal solution. Secondly, to reduce unnecessary communication transmission and control cost, an event-triggered algorithm is designed. Moreover, the convergence of the algorithm is proved, and the Zeno behavior can be avoided based on strict theoretic analysis. Finally, one example is given to verify the good performance of the proposed algorithms. [ABSTRACT FROM AUTHOR]

In this paper, the finite-time distributed optimisation problem for multi-agent systems (MASs) is investigated by proposing a kind of new event-based aperiodically intermittent communication strategy. Firstly, the distributed optimisation problem with the sum of local objective functions is considered. A novel finite-time event-triggered intermittent control protocol is proposed over undirected networks, and some sufficient conditions are obtained to ensure the finite-time consensus of MASs and the asymptotical solvability of the optimisation problem. Secondly, a more general distributed optimisation problem, in which the optimisation objective is the convex combination of local objective functions, is considered and we also prove that MASs can achieve consensus in finite-time and asymptotically reach the optimal solution under the proposed protocol over directed networks. Finally, two numerical examples are given to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Medical image segmentation is a critical task for clinical diagnosis and research. However, dealing with highly imbalanced data remains a significant challenge in this domain, where the region of interest (ROI) may exhibit substantial variations across different slices. This presents a significant hurdle to medical image segmentation, as conventional segmentation methods may either overlook the minority class or overly emphasize the majority class, ultimately leading to a decrease in the overall generalization ability of the segmentation results. To overcome this, we propose a novel approach based on multi-step reinforcement learning, which integrates prior knowledge of medical images and pixel-wise segmentation difficulty into the reward function. Our method treats each pixel as an individual agent, utilizing diverse actions to evaluate its relevance for segmentation. To validate the effectiveness of our approach, we conduct experiments on four imbalanced medical datasets, and the results show that our approach surpasses other state-of-the-art methods in highly imbalanced scenarios. These findings hold substantial implications for clinical diagnosis and research.

CO 2 utilization and conversion are of great importance in alleviating the rising CO 2 concentration in the atmosphere. Here, a single-atom catalyst (SAC) is reported for electrochemical CO 2 utilization in both aqueous and aprotic electrolytes. Specifically, atomically dispersed Mn-N 4 sites are embedded in bowl-like mesoporous carbon particles with the functionalization of epoxy groups in the second coordination spheres. Theoretical calculations suggest that the epoxy groups near the Mn-N 4 site adjust the electronic structure of the catalyst with reduced reaction energy barriers for the electrocatalytic reduction of CO 2 to CO. The resultant Mn-single-atom carbon with N and O doped catalyst (MCs-(N,O)) exhibits extraordinary electrocatalytic performance with a high CO faradaic efficiency of 94.5%, a high CO current density of 13.7 mA cm -2 , and a low overpotential of 0.44 V in the aqueous environment. Meanwhile, as a cathode catalyst for aprotic Li-CO 2 batteries, the MCs-(N,O) with well-regulated active sites and unique mesoporous bowl-like morphology optimizes the nucleation behavior of discharge products. MCs-(N,O)-based batteries deliver a low overpotential and excellent cyclic stability of 1000 h. The findings in this work provide a new avenue to design and fabricate SACs for various electrochemical CO 2 utilization systems., (© 2023 Wiley-VCH GmbH.)

Background: The auxin indole-3-acetic acid (IAA) is a type of endogenous plant hormone with a low concentration in plants, but it plays an important role in their growth and development. The AUX/IAA gene family was found to be an early sensitive auxin gene with a complicated way of regulating growth and development in plants. The regulation of root growth and development by AUX/IAA family genes has been reported in Arabidopsis, rice and maize., Results: In this study, subcellular localization indicated that ZmIAA1-ZmIAA6 primarily played a role in the nucleus. A thermogram analysis showed that AUX/IAA genes were highly expressed in the roots, which was also confirmed by the maize tissue expression patterns. In maize overexpressing ZmIAA5 , the length of the main root, the number of lateral roots, and the stalk height at the seedling stage were significantly increased compared with those of the wild type, while the EMS mutant zmiaa5 was significantly reduced. The total number of roots and the dry weight of maize overexpressing ZmIAA5 at the mature stage were also significantly increased compared with those of the wild type, while those of the mutant zmiaa5 was significantly reduced. Yeast one-hybrid experiments showed that ZmTCP15/16/17 could specifically bind to the ZmIAA5 promoter region. Bimolecular fluorescence complementation and yeast two-hybridization indicated an interaction between ZmIAA5 and ZmARF5., Conclusions: Taken together, the results of this study indicate that ZmIAA5 regulates maize root growth and development by interacting with ZmARF5 under the specific binding of ZmTCP15/16/17 ., Competing Interests: The authors declare there are no competing interests., (©2022 Yang et al.)