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In-situ collaborative design of crosslinking and fluorination toward poly(1,3-dioxolane)for high-performance semi-solid lithium metal batteries
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作者 Dezhi Yang Yaqiong Zhu +2 位作者 Yanan Yang Yiyang Sun Tao Zhang 《Journal of Energy Chemistry》 2026年第1期880-890,I0020,共12页
In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still face... In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects. 展开更多
关键词 Poly(1 3-dioxolane) CROSSLINKING FLUORINATION Lithium metal batteries
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Controllable synthesis of hydrogen-bonded organic framework encapsulated enzyme for continuous production of chiral hydroxybutyric acid in a two-stage cascade microreactor 被引量:1
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作者 Danyang Zhao Qiangqiang Xue +1 位作者 Yujun Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 2025年第1期175-184,共10页
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded... Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA). 展开更多
关键词 Hydrogen-bonded organic framework Immobilized enzyme Synthesis Chiral hydroxycarboxylic acid BIOCATALYSIS Nanostructure
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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Integrated Sensing and Communications Network Design and Key Technologies for Low-Altitude Economy
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作者 Ma Dingyou Tang Jun +3 位作者 Zhang Qixun Wei Zhiqing Gao Feifei Feng Zhiyong 《China Communications》 2025年第9期81-102,共22页
With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzin... With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzing representative ap-plication scenarios to clarify the core requirements of the low-altitude economy for modern ISAC net-works.By investigating the distinctive characteris-tics of ISAC networks in low-altitude environments,it presents a comprehensive analysis of key challenges and identifies four major issues:challenges in pre-cise target detection,interference management,in-consistent sensing and communication coverage,and the complexity of air-ground coordination and han-dover.Based on fundamental theories and principles,the paper proposes corresponding solutions,encom-passing advanced technologies for precise target de-tection and recognition,high-reliability networked de-tection,robust interference management,and seamless air-ground collaboration.These solutions aim to es-tablish a solid foundation for the future development of intelligent low-altitude networks and ensure effec-tive support for emerging applications. 展开更多
关键词 integrated sensing and communications interference management low-altitude economy target detection
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Far-Field vs. Near-Field Propagation Channels: Key Differences and Impact on 6G XL-MIMO Performance Evaluation
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作者 Ding Zihang Zhang Jianhua +5 位作者 You Changsheng Tang Pan Xing Hongbo Yuan Zhiqiang Meng Jie Liu Guangyi 《China Communications》 2025年第10期186-198,共13页
Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more ... Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more likely to be located in the NF region.In this paper,we aim to answer two questions:What are the new characteristics of the NF channel?Is it necessary to develop new transciver techniques to maintain system performance within the NF region?To this end,we first review current NF channel models and analyze the differences between the existing 3GPP TR 38.901 channel model and the NF channel model,including the spherical wavefront and spatially non-stationarity.Then,we provide ex-amples on how these differences affect the XL-MIMO system performance in terms of beamforming gain and achievable rate.Simulation results demonstrate that,when using far-field(FF)technique under the NF channel,the maximum normalized beam gain loss is less than 3 dB for most users in the NF region de-fined by Rayleigh distance.Moreover,the achievable rate loss of beam training is less than 3%compared to that realized by NF technique.Finally,we demonstrate the necessity of employing NF transceiver techniques based on simulation results. 展开更多
关键词 channel model near-field communica-tion near-field effect spatial non-stationary
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Published as part of the Journal of Electrochemistry special issue “In-Depth Reflections on the Top Ten Scientific Questions in Electrochemistry”. Strategies for Obtaining High-Performance Li-Ion Solid-State Electrolytes for Solid-State Batteries
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作者 Yi-Cheng Deng Zi-Chang You +14 位作者 Geng-Zhong Lin Guo Tang Jing-Hua Wu Zhi-Min Zhou Xiang-Chun Zhuang Li-Xuan Yang Zhen-Jie Zhang Zhao-Yin Wen Xia-Yin Yao Chang-Hong Wang Qian Zhou Guang-Lei Cui Ping He Hui Li Xin-Ping Ai 《电化学(中英文)》 北大核心 2025年第10期1-55,共55页
With the widespread adoption of lithium-ion batteries(LIBs),safety concerns associated with flammable organic elec-trolytes have become increasingly critical.Solid-state lithium batteries(SSLBs),with enhanced safety a... With the widespread adoption of lithium-ion batteries(LIBs),safety concerns associated with flammable organic elec-trolytes have become increasingly critical.Solid-state lithium batteries(SSLBs),with enhanced safety and higher energy density potential,are regarded as a promising next-generation energy storage technology.However,the practical appli-cation of solid-state electrolytes(SSEs)remains hindered by several challenges,including low Li^(+)ion conductivity,poor interfacial compatibility with electrodes,unfavorable mechanical properties and difficulties in scalable manufacturing.This review systematically examines recent progress in SSEs,including inorganic types(oxides,sulfides,halides),organic types(polymers,plastic crystals,poly(ionic liquids)(PILs)),and the emerging class of soft solid-state electrolytes(S3Es),especially those based on“rigid-flexible synergy”composites and“Li+-desolvation”mechanism using porous frameworks.Critical assessment reveals that single-component SSEs face inherent limitations that are difficult to be fully overcome through compositional and structural modification alone.In contrast,S3Es integrate the strength of complementary components to achieve a balanced and synergic enhancement in electrochemical properties(e.g.,ionic conductivity and stability window),mechanical integrity,and processability,showing great promise as next-generation SSEs.Furthermore,the application-ori-ented challenges and emerging trends in S3E research are outlined,aiming to provide strategic insights into future develop-ment of high-performance SSEs. 展开更多
关键词 Solid-state electrolytes Solid-state batteries Soft solid-state electrolytes Lithium-ion conductivity Interface compatibility
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An interfacial compatible Ti_(4)P_(8)S_(29) polysulfide cathode with open channels for high-rate solid-state polymer sodium batteries
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作者 You-Tan Pan Xue Wang +5 位作者 Bai-Xin Peng Ke-Yan Hu Chong Zheng Yu-Qiang Fang Wu-Jie Dong Fu-Qiang Huang 《Rare Metals》 2025年第5期3008-3015,共8页
Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a ... Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a great challenge for their commercial application.In contrast,soft sulfur-based materials feature better interface contact and chemical compatibility.Herein,an interfacial compatible polysulfide Ti_(4)P_(8)S_(29) with robust Ti-S bonding and a highly active P-S unit is tailored as a high-performance cathode for SPSBs.The Ti_(4)P_(8)S_(29) cathode possesses a three-dimensional channel structure for offering ample Na+diffusion pathways.The assembled poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)-based SPSBs deliver a discharge capacity of 136 mAh·g^(-1)at 0.5C after 200 cycles.Furthermore,a discharge capacity of 88 mAh·g^(-1)is retained after 600 cycles at a high rate of 2C,surpassing many cathode materials in SPSBs.A dual-site redox of Ti^(4+)/Ti^(3+)and S^(-)/S^(2-)is verified by X-ray photoelectron spectroscopy(XPS)and cyclic voltammetry(CV)tests.Interestingly,a refined locally-ordered amorphous structure is unveiled by in situ and ex situ characterizations.The as-formed electrode structure with lots of open channels and isotropic properties are more beneficial for ion diffusion on the interface of electrode and solid-state polymer electrolytes(SPEs),leading to faster Na+diffusion kinetics.This work proposes a strategy of modulating open-channel to boost conversion kinetics in polysulfide cathode and opens a new pathway for designing high-performance SPSBs. 展开更多
关键词 Solid-state sodium batteries POLYSULFIDES Ti4P8S29 Open-channel High-rate
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Constructing A Theoretical Model to Bridge Neural Transition with a State Switch in Bipolar Disorder
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作者 Xiaonan Guo Lizichen Chen +1 位作者 Jianbo Lai Shaohua Hu 《Neuroscience Bulletin》 2025年第1期181-185,共5页
Reward or stress,which exists extensively,causes resilient emotional fluctuations under common situations.However,reward or stress is a typical trigger for manic or depressive episodes of bipolar disorder(BD),which is... Reward or stress,which exists extensively,causes resilient emotional fluctuations under common situations.However,reward or stress is a typical trigger for manic or depressive episodes of bipolar disorder(BD),which is corroborated by psychological theory,biological findings,and psychosocial treatment approaches[1,2].During an episode of BD,the affective aberration can be persistent and switchable,accompanied by opposite constellations of cognitive and psychomotor symptoms.Characterized by uncontrollable mood ranging in severity,duration,and polarity,to disentangle the pathophysiology mechanism of BD is to delineate the mystery of affective fluctuations driven by reward or stress. 展开更多
关键词 BIPOLAR TRANSITION finding
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On AlN_(P)/Mg-Zn-Cu cast composites with low expansion and high thermal conductivity
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作者 Shu-sen Wu Lu Chen +2 位作者 Shu-lin Lü Wei Guo Jian-yu Li 《China Foundry》 2026年第1期101-107,共7页
There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with h... There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with high thermal conductivity.Furthermore,it explores the preparation of AlN_(P)/Mg-Zn-Cu composites featuring low coefficients of thermal expansion.The stir casting method was utilized to fabricate the composites and an investigation was conducted to examine their microstructure and thermal properties.Results indicate that the addition of AlN_(P)reduces the thermal expansion coefficient while maintaining relatively high thermal conductivity.Specifically,the AlN_(P)/Mg-0.5Zn-0.5Cu composite with 30wt.%AlN_(P)achieves a thermal conductivity of 132.7 W·m^(-1)·K^(-1)and a thermal expansion coefficient of 18.5×10^(-6)K^(-1),rendering it suitable for electronic packaging applications where thermal management is critical. 展开更多
关键词 thermal expansion thermal conductivity magnesium-matrix composites Mg-Zn-Cu alloy
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The path to carbon neutral shipping:A comparative analysis of low carbon technologies
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作者 Zhengang Zhou Zhicheng Wu +8 位作者 Chang Liu Lingyu Shao You Zhang Weijie Liu Haitao Shen Dongwei Yao Haidong Fan Chenghang Zheng Xiang Gao 《Journal of Environmental Sciences》 2026年第1期606-616,共11页
Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in mariti... Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future. 展开更多
关键词 SHIP Low carbon ASSESSMENT Alternative fuel Carbon capture
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Development of in-situ porous Ti particle reinforced Mg-Cu-Gd metallic glass matrix composite with dual-scale reinforcing structures
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作者 Yuman Shao Dijia Zhao +3 位作者 Wei Guo Shulin Lü Jincheng Wang Shusen Wu 《Journal of Magnesium and Alloys》 2026年第1期380-395,共16页
In the present work,the porous Ti particle reinforced Mg-based bulk metallic glass matrix composites(BMGCs)have been successfully fabricated via a novel in-situ dealloying method in metallic melt.A dual reinforcing st... In the present work,the porous Ti particle reinforced Mg-based bulk metallic glass matrix composites(BMGCs)have been successfully fabricated via a novel in-situ dealloying method in metallic melt.A dual reinforcing structure,including large-scale between porous particles and fine-scale inside one particle,was induced to further overcome the strength-plasticity tradeoff.The microstructure and mechanical properties of such dual-scale structure-reinforced BMGCs with various volume fractions and diameters of porous Ti particles were investigated in detail.It is found that with more and finer porous Ti particles,the BMGC showed both high fracture strength(1131.9±39.1 MPa)and good plastic deformability(1.48±0.38%).The characteristic of the reinforcing structure(0.48μm)inside the porous particles was close to the plastic processing zone size of the matrix(0.1~0.2μm),which generated a locally ideal reinforcing structure.Such dual-scale reinforcing structures with more interfaces can effectively promote the multiplication of shear bands at the interfaces.Due to the size effect,the refined submicron matrix between the Ti ligaments inside the porous particles should exhibit homogeneous shearing events.Such delocalization behavior from the dual-scale reinforcing structures should help to enhance the role of the interactions between shear bands,thus improving the yield strength of the composites.Based on the in-situ dealloying method,the dual-scale structure design provides a novel approach to fabricate various BMGCs with both high strength and good plasticity. 展开更多
关键词 Metallic glass matrix composite Porous particle In-situ dealloying method Dual-scale reinforcing structure
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Multi-Attribute and Multi-Point Cooperative Handover Strategy for LEO Satellite Communication Systems
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作者 Li Hongguang Liu Yaoqi +2 位作者 Shi Jinglin Zhou Yiqing Qian Manli 《China Communications》 2026年第1期154-165,共12页
LEO satellite communication systems have the characteristics of high-speed and periodic movement.The handover of user link occurs frequently,which has a serious impact on user terminal application and system capacity.... LEO satellite communication systems have the characteristics of high-speed and periodic movement.The handover of user link occurs frequently,which has a serious impact on user terminal application and system capacity.To address this issue,we propose a handover strategy of LEO satellite user terminal based on multi-attribute and multi-point(MAMP)cooperation.Firstly,the satellite-user-time matrix is established by using the satellite constellation coverage and handover model.Then,combined with the visual time and signal quality,the user access matrix and satellite load matrix are extracted to determine the weight equation of the handover strategy with the channel reservation.According to the system modeling simulation,the algorithm improves the handover success rate by 2.5%,the lasted call access success rate by 3.2%,the load balancing degree by 20%,and the robustness by two orders of magnitude. 展开更多
关键词 HANDOVER LEO satellite load balancing MULTI-ATTRIBUTE
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Brain insulin resistance and neuropsychiatric symptoms in Alzheimer's disease:A role for dopamine signaling
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作者 Anastasia Kontogianni Hongbin Yang Wenqiang Chen 《Neural Regeneration Research》 2026年第5期1995-1996,共2页
Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central com... Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central complications.Type 2 diabetes mellitus(T2DM),the most prevalent type of diabetes,affects more than 38 million individuals in the United States(approximately 1 in 10)and is defined by chronic hyperglycemia and insulin resistance,which refers to a reduced cellular response to insulin. 展开更多
关键词 reduced cellular response insulin dopamine signaling insulin resistancewhich metabolic disorder type diabetes mellitus brain insulin resistance Alzheimers disease neuropsychiatric symptoms
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High‑Entropy Amorphous Catalysts for Water Electrolysis:A New Frontier
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作者 Gaihong Wang Zhijie Chen +4 位作者 Jinliang Zhu Jiangzhou Xie Wei Wei Yi‑Ming Yan Bing‑Jie Ni 《Nano-Micro Letters》 2026年第3期141-179,共39页
High‐entropy amorphous catalysts(HEACs)integrate multielement synergy with structural disorder,making them promising candidates for water splitting.Their distinctive features—including flexible coordination environm... High‐entropy amorphous catalysts(HEACs)integrate multielement synergy with structural disorder,making them promising candidates for water splitting.Their distinctive features—including flexible coordination environments,tunable electronic structures,abundant unsaturated active sites,and dynamic structural reassembly—collectively enhance electrochemical activity and durability under operating conditions.This review summarizes recent advances in HEACs for hydrogen evolution,oxygen evolution,and overall water splitting,highlighting their disorder-driven advantages over crystalline counterparts.Catalytic performance benchmarks are presented,and mechanistic insights are discussed,focusing on how multimetallic synergy,amorphization effect,and in‐situ reconstruction cooperatively regulate reaction pathways.These insights provide guidance for the rational design of next‐generation amorphous high‐entropy electrocatalysts with improved efficiency and durability. 展开更多
关键词 High‐entropy amorphous catalysts ELECTROCATALYSIS Water splitting Structural disorder Multimetallic synergy
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Microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states 被引量:11
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作者 LI Yongjun ZHANG Kui +2 位作者 ZHANG Ya LI Xinggang MA Minglong 《Rare Metals》 SCIE EI CAS CSCD 2010年第3期317-322,共6页
The microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states were studied.The results reveal that island compounds at the grain boundaries of the as-cast alloys m... The microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states were studied.The results reveal that island compounds at the grain boundaries of the as-cast alloys mainly were Mg24Y5,Mg41Nd5,and Mg5Gd phases.After homogenization at 808 K for 24 h,the distribution of the island compounds became discrete and Mg5Gd phases mostly decomposed and dissolved.With hot extrusion,the grain size was refined to about 20 μm on average,and both the strength and elongation were greatly improved.After ageing at 523 K for 5 h,the strength of different extruded alloys largely increased but the elongation decreased.With the increase of neodymium content,the strength of the alloys at different states increased.The content of neodymium element had an obvious effect on the elongation of the designed alloys.In the designed alloys,the Mg-5Y-5Gd-2.2Nd-0.5Zr alloy exhibited the best combination properties and its ultimate tensile strength,yield strength,and elongation could reach 380 MPa,285 MPa,and 9.0%,respectively. 展开更多
关键词 magnesium alloys NEODYMIUM EXTRUSION HOMOGENIZATION microstructural evolution mechanical properties
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Disassemblability Modeling Technology of Configurable Product Based on Disassembly Constraint Relation Weighted Design Structure Matrix(DSM) 被引量:4
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作者 QIU Lemiao LIU Xiaojian +1 位作者 ZHANG Shuyou SUN Liangfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期511-519,共9页
The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disa... The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix (DSM) is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized. 展开更多
关键词 disassemblability modeling disassembly entropy disassembling degree weighted DSM product configuration model
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Evolution of rheocast microstructure of AZ31 alloy in semisolid state 被引量:7
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作者 Xing Bo Li Yuandong +2 位作者 Ma Ying Chen Tijun Hao Yuan 《China Foundry》 SCIE CAS 2013年第4期221-226,共6页
Semisolid rheoforming (SSR) is a promising technology for the production of Mg wrought alloy in foundry settings. In order to realize SSR, it is necessary to characterize the grain structure evolution during slurry ... Semisolid rheoforming (SSR) is a promising technology for the production of Mg wrought alloy in foundry settings. In order to realize SSR, it is necessary to characterize the grain structure evolution during slurry preparation. In this paper, slurry of AZ31 alloy was produced by a novel rheocast process known as self-inoculation method (SIM). Interrupted quenching technology was applied to investigate the primary a-Mg evolution during continuous cooling and isothermal holding. Results indicate that the initial microstructure of slurry produced by SIM is a mixture of irregular grains, which becomes ideally globular when the slurry slowly cools to 620 ~C and isothermally held for at least 30 s. The local solute diffusion leads to dendritic fragmentation and forms separated particles. During prolonged holding, the particle surface gradually becomes smooth because of protuberance melting and groove advancement. Coarsening of a-Mg grains in isothermal holding was analyzed using Lifshitz-Slyozov-Wagner theory. Results suggest that coalescence is most likely the dominant coarsening mechanism in the early stage while Ostwald ripening tends to be the principal one later. The EDS results indicate that a longer holding time leads to AI solute element segregation at the grain boundaries, but Zn distribution within liquid matrix has no obvious change. 展开更多
关键词 rheocast microstructure evolution mechanism AZ31 alloy quiescent state
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Boosting redox activity on MXene-induced multifunctional collaborative interface in high Li2S loading cathode for high-energy Li-S and metallic Li-free rechargeable batteries 被引量:8
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作者 Zhiyu Wang Nan Zhang +3 位作者 Mingliang Yu Junshan Liu Song Wang Jieshan Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期183-191,共9页
Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic... Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic Li exists in the cells. Pairing lithium sulfide (Li2S) cathode with currently available metallic Lifree high-capacity anodes offers an alternative solution to this challenge. However, the performance of Li2S cathode is primarily restricted by high activation barrier upon initial charge, low active mass utilization and sluggish redox kinetics. Herein, a MXene-induced multifunctional collaborative interface is proposed to afford superb activity towards redox solid-liquid/liquid-liquid phase transformation, strong chemisorption, high conductivity and fast ionic/charge transport in high Li2S loading cathode. Applying collaborative interface effectively reduces initial voltage barrier of Li2S activation and regulates the kinetic behavior of redox polysulfide conversion. Therefore, stable operation of additive-free Li2S cathode with high areal capacities at high Li2S loading up to 9 mg cm^-2 can be achieved with less sacrifice of high capacity and rate capability in Li-S batteries. Rechargeable metallic Li-free batteries are successfully constructed by pairing this high-performance Li2S cathode with high-capacity metal oxide anodes, which delivers superior energy density to current Li-ion batteries. 展开更多
关键词 Lithium SULFIDE HIGH-CAPACITY CATHODE INTERFACE MXene Li-S batteries
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Sulfur deposition in sour gas reservoirs:laboratory and simulation study 被引量:4
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作者 Xiao Guo Zhimin Du +2 位作者 Xuefeng Yang Yong Zhang Dekui Fu 《Petroleum Science》 SCIE CAS CSCD 2009年第4期405-414,共10页
Sulfur deposition in the formation, induced by a reduction in the solubility of the sulfur in the gas phase, may significantly reduce the inflow performance of sour gas wells and some wells in sour gas reservoirs have... Sulfur deposition in the formation, induced by a reduction in the solubility of the sulfur in the gas phase, may significantly reduce the inflow performance of sour gas wells and some wells in sour gas reservoirs have even become completely plugged with deposited sulfur within several months. Accurate prediction and effective management of sulfur deposition are crucial to the economic viability of sour gas reservoirs. In this paper, a dynamic flow experiment was carried out to investigate formation damage resulting from sulfur deposition using an improved experimental method. The core sample was extracted from the producing interval of the LG2 well, LG gas field in the Sichuan Basin. The experimental temperature was 26 °C and the initial pressure was 19 MPa. The displacement pressure continuously decreased from 19 to 10 MPa, and the depletion process lasted 15 days. Then the core was removed and dried. The core mass and core permeability were measured before and after experiments. Experimental results indicated that the core mass increased from 48.372 g before experiment to 48.386 g afterwards, while the core permeability reduced from 0.726 to 0.608 md during the experiment. Then the core was analyzed with a scanning electron microscope (SEM) and energy-dispersive X-ray mapping. The deposition pattern and micro-distribution of elemental sulfur was observed and the deposited elemental sulfur distributed as a film around the pore surface. 展开更多
关键词 Sour gas reservoir sulfur deposition EXPERIMENT numerical simulation formation damage
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Modeling of Normal Perforation of Reinforced Concrete Slabs by a Rigid Projectile 被引量:5
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作者 CHEN Xiaowei LI Xiaoli 《Transactions of Tianjin University》 EI CAS 2006年第B09期107-111,共5页
An analytical model on the normal perforation of reinforced concrete slabs is constructed. The effect of reinforcing bars is further hybridized in a general three-stage model consisting of initial cratering, tunnellin... An analytical model on the normal perforation of reinforced concrete slabs is constructed. The effect of reinforcing bars is further hybridized in a general three-stage model consisting of initial cratering, tunnelling and shear plugging. Besides three dimensionless numbers, i. e., the impact function I, the geometry function of projectile N and the dimensionless thickness of concrete target X, which are employed to predict the ballistic performance of perforation of concrete slabs, the reinforcement ratio Ps of concrete and the tensile strength fs of reinforcing bars are considered as the other main factors influencing the perforation process. Simpler solutions of ballistic performances of normal perforation of reinforced concrete slabs are formulated. Theoretical predictions agree well with individual published experimental data. 展开更多
关键词 normal perforation ballistic limit reinforced concrete rigid projectile impact
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