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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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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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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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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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Mesoporous N-rich carbon nanospheres regulating high dispersion of red phosphorus for sodium-ion batteries
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作者 Hongyi Zhang Wenda Li +7 位作者 Hao Luo Lingyan Huang Facai Wei Shanzhe Ke Liguo Ma Chengbin Jing Jiangong Cheng Shaohua Liu 《Chinese Chemical Letters》 2026年第2期606-610,共5页
The intrinsic insulation and drastic volume change of the red phosphorus during the 3-electron alloying process greatly limits its widespread applications in sodium-ion batteries.Here,we report a monomicelle-directed ... The intrinsic insulation and drastic volume change of the red phosphorus during the 3-electron alloying process greatly limits its widespread applications in sodium-ion batteries.Here,we report a monomicelle-directed assembly approach for controllable synthesis of monodispersed mesoporous polypyrrole(PPy)nanospheres,which allows for the shape-preserving conversion into N-doped carbon with regular mesoscopic pore and high surface area,thus affording a high dispersion of red phosphorus during melt impregnation process due to the available diffusion apertures and strong molecular chemical anchoring.Moreover,the theoretical calculations further revealed that positively polarized pyridine N atoms in N-doped mesoporous carbon nanospheres can empower comprehensive regulation of red phosphorus adsorption by strong chemical binding.Benefitting from the above advantages,the resultant red phosphorus host for sodium-ion batteries delivered an outstanding reversible capacity of 856 mAh/g with a capacity fading rate of only 0.025%per cycle during 1000 cycles at 1.0 A/g.This work provides an effective approach based on monomicelle-directed assembly engineering of carbon-based phosphorus hosts for advanced energy conversion and storage systems. 展开更多
关键词 Mesoporous materials N-doped carbon nanospheres Monomicelle-directed assembly Phosphorus hosts Sodium-ion batteries
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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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Traits improvement of wild rice O. rufipogon via multiplex genome editing
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作者 Chang Tian Xu Tang +11 位作者 Guangzhong Zhang Rui Zhang Xinruolan Yang Lei Ding Caiyun Yin Hongfei Lin Fenglin Su Suikang Wang Xiaoxia Li Lianguang Shang Yong Zhang Quan Wang 《Journal of Integrative Plant Biology》 2026年第1期20-22,共3页
Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from S... Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from South/Southeast Asian wild O. nivara(Jing et al., 2023). Genes like An-1, BH4, PROG1,SH4, Rc, Rd, and GS3—which regulate awn length, hull color,til er angle, seed shattering, pericarp color, seed length, and thousand-grain weight, respectively—were selected against during domestication to form modern O. sativa(Yu et al., 2021).However, domestication and yield-focused breeding eliminated wild rice's valuable genes(e.g., for disease resistance, stress tolerance, nutrition), narrowing genetic diversity and impeding efforts to meet growing societal demands. 展开更多
关键词 Oryza sativa cultivated oryza sativa genetic diversity Oryza rufipogon wild rice multiplex genome editing disease resistance food security
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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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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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Effect of cultivation time on soil heavy metal accumulation and bioavailability in Phyllostachys praecox stands 被引量:3
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作者 Renyi GUI Yuyan HU +1 位作者 Qiang LI Shunyao ZHUANG 《Pedosphere》 SCIE CAS CSCD 2020年第6期810-816,共7页
Phyllostachys praecox is a bamboo species cultivated for edible shoots under intensive management.However,the potential pollution risk of heavy metals in bamboo soils is not clear under the intensive management for a ... Phyllostachys praecox is a bamboo species cultivated for edible shoots under intensive management.However,the potential pollution risk of heavy metals in bamboo soils is not clear under the intensive management for a long term.The objective of this study was to evaluate the effect of cultivation time on soil heavy metal accumulation and bioavailability in bamboo stands subjected to intensive management.Soil samples were collected from a chronosequence of bamboo stands which had been cultivated for 0,1,2,4,8,and 10 years in Lin’an,Zhejiang Province of China.Eight heavy metals(Cu,Zn,Pb,Ni,Cr,Cd,As,and Hg)present in the soil were selected,and their potential pollution risk was evaluated by chemical speciation analysis.Possible heavy metal sources were explored using multivariate and cluster analysis.Our results showed that Zn,Cu,Hg,and Cd contents in the soil increased with the cultivation time,while Ni,Cr,Pb,and As levels were similar among all stands.Furthermore,the bioavailabilities of all analyzed heavy metals increased with the cultivation time.Multivariate and cluster analysis showed that sources of Ni,Cr,Pb,and As were likely lithogenic in origin,whereas input of Zn,Cu,Hg,and Cd was mainly due to cultivation practices.Current bamboo management strategies raised the potential risks of heavy metal pollution in bamboo shoots in the long term.Soil acidification in P.praecox stands induced by intensive cultivation should be controlled since it stimulated and improved the bioavailability of heavy metals.Appropriate management strategies should thus be adopted to ensure safe and sustainable production of bamboo shoots. 展开更多
关键词 chemical fraction cluster analysis intensive management multivariate statistics soil acidification
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Facile Synthesis of Uniform Hollow Hematite Sub-micro Spheres with Controllable Shell Thickness 被引量:3
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作者 闫共芹 官建国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第1期32-38,共7页
A simple method was developed to prepare the uniform hematite hollow submicro-spheres with controllable structure and different diameter based on monodisperse poly(styrene-co-acrylic acid) [P(St-co-AA)] particles.... A simple method was developed to prepare the uniform hematite hollow submicro-spheres with controllable structure and different diameter based on monodisperse poly(styrene-co-acrylic acid) [P(St-co-AA)] particles. The structure and formation mechanism of the hollow spheres were investigated in detail. The control mechanism of shell thickness was also discussed. The results indicated that the shell thickness and coarseness of the synthesized core-shell hematite hollow spheres could be tuned simply by the surface carboxyl content of the P(St-co-AA) particles. This method provided a new approach for the structure control in the preparation of hollow spheres. A Brunauer-Emmett-Teller (BET) test shows that the prepared hollow spheres have large surface areas which were decreased along with the increase of the diameter. The magnetic properties of the as-obtained hematite hollow spheres were investigated. The result showed that the coercivity and saturated magnetization were increased along with the increase of the shell thickness, and the remanent magnetization was increased along with the decrease of the diameter. 展开更多
关键词 hollow spheres HEMATITE shell thickness BET special surface area magnetization properties
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