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The escalating focus on environmental concerns and the swift advancement of eco‐friendly biodegradable batteries raises a pressing demand for enhanced material design in the battery field. The traditional polypropylene (PP) that is monopolistically utilized in the commercial LIBs is hard to recycle. In this work, we prepare a novel water degradable separators via the cross‐linking of polyvinyl alcohol (PVA) and dibasic acid (tartaric acid, TA). Through the integration of non‐solvent liquid‐phase separation, we successfully produced a thermally stable PVA‐TA membrane with tunable thickness and a high level of porosity. These specially engineered PVA‐TA separators were implemented in LiFePO4 (LFP)|separator|Li cells, resulting in superior multiplicative performance and achieving a capacity of 88 mAh g−1 under 5 C. Additionally, the straightforward small molecule cross‐linking technique significantly reduced the crystalline region of the polymer, thereby enhancing ionic conductivity. Notably, after cycling, the PVA‐TA separators can be easily dissolved in 95 °C hot water, enabling its reutilization for the production of new PVA‐TA separators. Therefore, this work introduces a novel concept to design green and sustainable separators for recyclable lithium batteries. [ABSTRACT FROM AUTHOR]

Depression is a common neuropsychiatric disease which brings an increasing burden to all countries globally. Baicalin, a flavonoid extracted from the dried roots of Scutellaria, has been reported to exert anti-inflammatory, antioxidant, and neuroprotective effects in the treatment of depression. However, the potential biological mechanisms underlying its antidepressant effect are still unclear. In the present study, we conducted extensive research on the potential mechanisms of baicalin's antidepressant effect using the methods of network pharmacology, including overlapped terms-based analysis, protein–protein interaction (PPI) network topology analysis, and enrichment analysis. Moreover, these results were further verified through molecular docking, weighted gene co-expression network analysis (WGCNA), differential gene expression analysis, and subsequent animal experiments. We identified forty-one genes as the targets of baicalin in the treatment of depression, among which AKT1, IL6, TP53, IL1B, and CASP3 have higher centrality in the more core position. Meanwhile, the roles of peripheral genes derived from direct potential targets were also observed. Our study suggested that biological processes, such as inflammatory reaction, apoptosis, and oxidative stress, may be involved in the therapeutic process of baicalin on depression. These mechanisms were validated at the level of structure, gene, protein, and signaling pathway in the present study. Taken together, these findings propose a new perspective on the potential mechanisms underlying baicalin's antidepressant effect, and also provide a new basis and clarified perspective for its clinical application. [ABSTRACT FROM AUTHOR]

The conversion of CO2 into fuels or commodity chemicals by electrochemical or photochemical reduction is a promising strategy to relieve the ongoing energy crisis and increasing environmental pollution. Inspired by naturally occurring bimetalloenzymes, we have designed hetero–bimetallic CO2 reduction catalysts (FeM) that involve linking an iron tetraphenylporphyrin (FeP) with a tripyridylamine (TPA) moiety, which provides a distal chelating site for Cu2+ or Zn2+. We found that the introduction of Cu2+ or Zn2+ to FeP greatly enhances its efficiency as a catalyst for the electrochemical reduction of CO2. To gain insights into the observed synergistic effect, we performed mechanistic studies together with density functional theory (DFT) calculations. Our results show that Cu2+ or Zn2+ activates CO2 towards reduction due to its Lewis acidity; it also functions as an oxo acceptor from CO2. FeM also functions as an efficient catalyst for the visible‐light‐driven reduction of CO2 using either [Ru(bpy)3] Cl2 or fac‐Ir(ppy)3 (where bpy=2,2'‐bipyridine, ppy=2‐phenylpyridine) as photosensitizer and 1,3‐dimethyl‐2‐phenyl‐2,3‐dihydro‐1H‐benzo[d] imidazole (BIH) as sacrificial reductant. Again, the catalytic efficiency is enhanced by the presence of Cu2+ or Zn2+. Our results provide a general strategy for the design of a series of hetero‐bimetallic catalysts for the reduction of CO2. [ABSTRACT FROM AUTHOR]

Although hard carbon (HC) demonstrates superior initial Coulombic efficiency, cycling durability, and rate capability in ether‐based electrolytes compared to ester‐based electrolytes for sodium‐ion batteries (SIBs), the underlying mechanisms responsible for these disparities remain largely unexplored. Herein, ex situ electron paramagnetic resonance (EPR) spectra and in situ Raman spectroscopy are combined to investigate the Na storage mechanism of HC under different electrolytes. Through deconvolving the EPR signals of Na in HC, quasi‐metallic‐Na is successfully differentiated from adsorbed‐Na. By monitoring the evolution of different Na species during the charging/discharging process, it is found that the initial adsorbed‐Na in HC with ether‐based electrolytes can be effectively transformed into intercalated‐Na in the plateau region. However, this transformation is obstructed in ester‐based electrolytes, leading to the predominant storage of Na in HC as adsorbed‐Na and pore‐filled‐Na. Furthermore, the intercalated‐Na in HC within the ether‐based electrolytes contributes to the formation of a uniform, dense, and stable solid–electrolyte interphase (SEI) film and eventually enhances the electrochemical performance of HC. This work successfully deciphers the electrolyte‐dominated Na+ storage mechanisms in HC and provides fundamental insights into the industrialization of HC in SIBs. [ABSTRACT FROM AUTHOR]

With the advancement of space technology and satellite communications, low-Earth-orbit (LEO) satellite networks have experienced rapid development in the past decade. In the vision of 6G, LEO satellite networks play an important role in future 6G networks. On the other hand, a variety of applications, including many delay-sensitive applications, are continuously emerging. Due to the highly dynamic nature of LEO satellite networks, supporting time-deterministic services in such networks is challenging. However, we can provide latency guarantees for most delay-sensitive applications through data plane traffic shaping and control plane routing optimization. This paper addresses the routing optimization problem for time-sensitive (TS) flows in software-defined low-Earth-orbit (LEO) satellite networks. We model the problem as an integer linear programming (ILP) model aiming to minimize path handovers and maximum link utilization while meeting TS flow latency constraints. Since this problem is NP-hard, we design an efficient longest continuous path (LCP) approximation algorithm. LCP selects the longest valid path in each topology snapshot that satisfies delay constraints. An auxiliary graph then determines the routing sequence with minimized handovers. We implement an LEO satellite network testbed with Open vSwitch (OVS) and an open-network operating system (ONOS) controller to evaluate LCP. The results show that LCP reduces the number of path handovers by up to 31.7% and keeps the maximum link utilization lowest for more than 75% of the time compared to benchmark algorithms. In summary, LCP achieves excellent path handover optimization and load balancing performance under TS flow latency constraints. [ABSTRACT FROM AUTHOR]

In this study, the mechanical properties and damage modes of pultruded glass fiber/unsaturated polyester composite square pipe for automotive parts were investigated. The pipe structure, fiber mass content, dynamic mechanical analysis, tensile, and bending properties and acoustic emission detection damage mechanism of pultruded glass fiber composite pipe were studied. The structure of the cross‐section of the pultrusion pipe is like a sandwich composed of mat layers on both surfaces and a unidirectional fiber layer in middle. Based on the failure analysis of pipe by acoustic emission signal technology, it is found that the tensile damage process was considered into four stages, initial damage, mat layer fracture, intermediate damage, and fiber fracture; while the bending damage process can be divided into two stages as initial and overall damages. [ABSTRACT FROM AUTHOR]

It is highly desirable to raise the charge cutoff voltage to realize the potential of LiCoO2 (LCO) with its ultra‐high theoretical capacity of 275 mAh g‐1. However, rapid fading due to structure collapse caused by the formation of the H1‐3 metastable phase and the release of surface lattice oxygen has largely hindered the operation of LCO under voltages of higher than 4.55 V. Here, stable cycling of LCO at 4.6 V through hierarchical doping engineering with inert P‐outside and active Ni‐inside dual doping is achieved. This ingenious outside‐in structure design enables Ni2+ occupation in the Li layer in the bulk layered phase and P gradient doping at the superficial lattice. Compared with the conventional inert element substitution strategy, the doped active Ni2+ can not only serve as a "pillar" to restrain the formation of the metastable H1‐3 phase, but also regulate the electronic structure of LCO and trigger the superexchange interaction of Ni2+‐O‐Co4+, together with strong P–O coordination to substantially suppress the lattice oxygen escape from the surface. Therefore, it considerably reduces the risk of layer structure collapse and consequently achieves stable and high‐capacity operation over 4.6 V. This hierarchical outside‐in doping strategy may serve as inspiration for stabilizing high energy electrode materials working under high voltages. [ABSTRACT FROM AUTHOR]

Fabrication of a highly porous sulfur host and using excess electrolyte is a common strategy to enhance sulfur utilization. However, flooded electrolyte limits the practical energy density of Li–S pouch cells. In this study, a novel Fe0.34Co0.33Ni0.33S2 (FCN) is proposed as host for sulfur to realize Ah‐level Li–S full cells demonstrating excellent electrochemical performances under 2 µL mg−1 lean electrolyte conditions. Moreover, Kelvin probe force microscopy shows that the FCN surface contains positive charge with a potential of ≈70 mV, improving the binding of polysulfides through Lewis acid base interaction. In particular, the FCN@S possesses inherent electrochemical activity of simultaneous anionic and cationic redox for lithium storage in the voltage window of 1.8–2.1 V, which additionally contributes to the specific capacity. Due to the low carbon content (≈10 wt%), the sulfur loading is as high as ≈6 mg cm−2, approaching an outstanding energy density of 394.9 and 267.2 Wh kg−1 at the current density of 1.5 and 4 mA cm−2, respectively. Moreover, after 60 cycles at 1.5 mA cm−2, the pouch cell still retains an energy of 300.2 Wh kg−1. This study represents a milestone in the practical applications of high‐energy Li–S batteries. [ABSTRACT FROM AUTHOR]

Aero-engine is an essential component of the aircraft. Due to the high cost of raw materials and precise structure, the maintenance cost of aero-engine is great. By repairing worn blades rather than replacing them with new ones, the aero-engine maintenance cost can be reduced effectively. For repairing worn blades, existing methods mainly generate tool path based on the reconstructed surface with the aid of CAM software. In this paper, an effective tool path generation method for repairing blades after additive manufacturing process is presented, which overcomes the low efficiency and complicated process weakness of existing methods. The tool path is generated directly with point clouds without surface fitting. By splitting point cloud and analyzing geometric parameters of points, machining areas could be recognized from the entire blade model. The cutter location point is generated by extending on the normal vector direction of the corresponding point. The five-axis tool path could be obtained by connecting cutter location points in turns. Tool path optimization is further studied after the generation process. These algorithms eliminate the time consumption caused by surface fitting operations, and could generate five-axis tool paths for repairing aero-engine blades efficiently. [ABSTRACT FROM AUTHOR]

Engineering nanoarray structures with favorable hydrophilicity is proposed to unlock the electrocatalysis of NiFe2O4 for the oxygen evolution reaction (OER). The resulting electrode, consisting of NiFe2O4 nanospindles directly grown on FeNi3 foam, features enlarged active surface area, high hydrophilicity and increased electronic conductivity, which achieves superior OER activity and remarkable durability. [ABSTRACT FROM AUTHOR]

Abstract We demonstrate an extremely facile in-situ pyrolysis followed by the reduction of partial Co2+ route to synthesize novel Ketjen black carbon (KB) supported CoO@Co−N−C (denoted as CoO@Co−NC/KB) nanochains using KB, urea and cobalt (Ⅱ) acetate as co-precursors. The as-prepared CoO@Co-NC/KB displays higher electrocatalytic activity, smaller Tafel slope and better durability for the oxygen evolution reaction than those of the benchmark commercial RuO 2 catalyst in 1.0 M KOH solution, far outperforming the control groups (i.e. CoO@Co−g-C 3 N 4 /KB, Co−NC/KB, CoO−NC/KB, CoO@Co/KB, CoO@Co−NC and Co 3 O 4 −NC/KB). The remarkable electrocatalytic performance of CoO@Co−NC/KB is primarily credited to the synergistic effect between Co and CoO species with a core-shell structure, increased active sites and considerably enhanced electronic conductivity. Highlights • We demonstrate a facile route to fabricate a novel CoO@Co−NC/KB hybrid. • CoO@Co−NC/KB denotes Ketjen black carbon supported CoO@Co−N−C nanochains. • CoO@Co−NC/KB shows excellent electrocatalytic comprehensive performance for OER. • The superb catalytic performance of CoO@Co−NC/KB stems from its rational structure. [ABSTRACT FROM AUTHOR]

In this work, highly soluble LiNO 3 was adopted as the neutrally aqueous electrolyte for active carbon (AC)-based electrochemical double-layer capacitors (EDLCs), of which the electrochemical performances were evaluated. Simultaneously, the physicochemical properties such as the ionic conductivity and viscosity of the LiNO 3 aqueous solution were investigated. As compared with the most studied Li 2 SO 4 aqueous solution, the LiNO 3 aqueous solution displays more favorable physicochemical properties and electrochemical performances as the neutral electrolytes for EDLCs. To be specific, the conductivity of the 5.0 M LiNO 3 aqueous solution can reach up to 154.8 mS cm −1  at 25 °C, which is nearly two times of the maximum conductivity of 77.6 mS cm −1 for the 2.0 M Li 2 SO 4 aqueous solution under the identical testing conditions. Even at a concentration as high as 9.0 M, the absolute viscosity of the LiNO 3 aqueous solution is only 2.4, while that of the Li 2 SO 4 aqueous solution achieves 3.0 at the maximum concentration of 2.5 M. Additionally, 5.0 M LiNO 3 aqueous solution exhibits a wide electrochemical potential stability window from −0.9 to 0.9 V (vs. SCE) at the AC electrode, giving rise to an operating cell voltage of 1.8 V, which is comparable to that of 2.0 M Li 2 SO 4 aqueous solution. Further, with the 5.0 M LiNO 3 aqueous solution as the electrolyte, the as-fabricated EDLC delivers an energy density up to 21.16 Wh Kg −1  at a power density of 100.09 W kg −1 , which is higher than 18.43 Wh Kg −1 for the EDLC with the 2.0 M Li 2 SO 4 aqueous electrolyte at the identical power density. Even though the power density reaches as high as 5970 W kg −1 , the energy density of the EDLC with the 5.0 M LiNO 3 aqueous electrolyte can still remain at 13.1 Wh Kg −1 , substantially higher than 8.71 Wh Kg −1 of the EDLC with the 2.0 M Li 2 SO 4 aqueous electrolyte at the same power density. Moreover, the EDLC with the 5.0 M LiNO 3 aqueous electrolyte also holds good cyclic stability. After 10000 charge–discharge cycles at a current density of 1 A g −1 and a cut-off voltage of 1.8 V, the capacity retention of this EDLC retains more than 90%. These results can render an insight to explore safe, eco-friendly, inexpensive and neutrally aqueous electrolytes for supercapacitors. [ABSTRACT FROM AUTHOR]

Although hard carbon (HC) demonstrates superior initial Coulombic efficiency, cycling durability, and rate capability in ether-based electrolytes compared to ester-based electrolytes for sodium-ion batteries (SIBs), the underlying mechanisms responsible for these disparities remain largely unexplored. Herein, ex situ electron paramagnetic resonance (EPR) spectra and in situ Raman spectroscopy are combined to investigate the Na storage mechanism of HC under different electrolytes. Through deconvolving the EPR signals of Na in HC, quasi-metallic-Na is successfully differentiated from adsorbed-Na. By monitoring the evolution of different Na species during the charging/discharging process, it is found that the initial adsorbed-Na in HC with ether-based electrolytes can be effectively transformed into intercalated-Na in the plateau region. However, this transformation is obstructed in ester-based electrolytes, leading to the predominant storage of Na in HC as adsorbed-Na and pore-filled-Na. Furthermore, the intercalated-Na in HC within the ether-based electrolytes contributes to the formation of a uniform, dense, and stable solid-electrolyte interphase (SEI) film and eventually enhances the electrochemical performance of HC. This work successfully deciphers the electrolyte-dominated Na + storage mechanisms in HC and provides fundamental insights into the industrialization of HC in SIBs., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

P2-type layered transition-metal oxides with anionic redox reactions are promising cathodes for sodium-ion batteries. In this work, a high-sodium-content P2-type Na 7/9 Li 1/9 Mg 1/9 Cu 1/9 Mn 2/3 O 2 (NLMC) cathode material is prepared by substituting Li/Mg/Cu for Mn sites in Na 2/3 MnO 2 . The Li/Mg ions trigger the anionic redox reaction, while the Cu ions enhance the structure stability during electrochemical cycling. As a result, the oxide has a high reversible capacity of 225 mAh g -1 originating from both cationic and anionic redox activities with a capacity retention of 77% after 100 cycles. The migration energy barrier and Na ion diffusion kinetics are studied using density functional theory (DFT) calculations and the galvanostatic intermittent titration technique. Furthermore, X-ray diffraction, DFT, scanning electron microscopy, and transmission electron microscopy are applied to reveal the structural evolution and charge compensation of NLMC, providing a thorough understanding of the structural and morphology evolution of Na-deficient oxides during cycling. The results are inspiring for the design of a high-Na content P2-type layered oxide cathode for sodium-ion batteries.

N-doped carbon coated TiO 2 nanoparticles (TiO 2 @NC) were synthesized through a simple two-step route, in which dopamine was simultaneously utilized as both nitrogen and carbon sources. With TiO 2 @NC applied in the Na-ion battery (SIB) anodes, the continuous and uniform N-doped carbon layer can not only enhance the electrical conductivity of TiO 2 and facilitate the surface pseudocapacitive process, but also serve as a buffer layer to accommodate the volume expansion during the sodiation-desodiation processes. The as-prepared TiO 2 @NC exhibits excellent electrochemical performance when utilized as the SIB anodes, which delivers a remarkably high reversible capacity of 250.2 mAh g -1 at a rate of 0.25C (84 mA g -1 ) after 200 cycles and still retains 122.1 mAh g -1 at 10C (3.35 A g -1 ) even after 3000 cycles accompanied with a 95.3% retention of the maximum capacity, outperforming most of the reported TiO 2 /C-based composites as SIB anodes. To our best knowledge, the preparation of TiO 2 @NC with dopamine as both nitrogen and carbon sources and its application in the SIB anodes are reported for the first time., (Copyright © 2018 Elsevier Inc. All rights reserved.)