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Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures 被引量:1
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作者 Xianfu Zhang Long Zhang +2 位作者 Xinyuan Jia Wen Song Yongchang Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期305-349,共45页
Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low re... Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented. 展开更多
关键词 Aqueous zinc metal batteries Zinc anodes high zinc utilization Depth of discharge Anode-free structures
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Ultrafast dynamics of femtosecond laser-induced high spatial frequency periodic structures on silicon surfaces 被引量:1
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作者 Ruozhong Han Yuchan Zhang +6 位作者 Qilin Jiang Long Chen Kaiqiang Cao Shian Zhang Donghai Feng Zhenrong Sun Tianqing Jia 《Opto-Electronic Science》 2024年第3期33-46,共14页
Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than t... Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than the diffraction limit,making it a useful method for efficient nanomanufacturing.However,compared with the low-spatial-frequency LIPSS(LSFL),the structure size of the HSFL is smaller,and it is more easily submerged.Therefore,the formation mechanism of HSFL is complex and has always been a research hotspot in this field.In this study,regular LSFL with a period of 760 nm was fabricated in advance on a silicon surface with two-beam interference using an 800 nm,50 fs femtosecond laser.The ultrafast dynamics of HSFL formation on the silicon surface of prefabricated LSFL under single femtosecond laser pulse irradiation were observed and analyzed for the first time using collinear pump-probe imaging method.In general,the evolution of the surface structure undergoes five sequential stages:the LSFL begins to split,becomes uniform HSFL,degenerates into an irregular LSFL,undergoes secondary splitting into a weakly uniform HSFL,and evolves into an irregular LSFL or is submerged.The results indicate that the local enhancement of the submerged nanocavity,or the nanoplasma,in the prefabricated LSFL ridge led to the splitting of the LSFL,and the thermodynamic effect drove the homogenization of the splitting LSFL,which evolved into HSFL. 展开更多
关键词 laser-induced periodic surface structures(LIPSS) local field enhancement collinear pump-probe imaging silicon high spatial frequency periodic structures
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Lignin‐derived carbon with pyridine N‐B doping and a nanosandwich structure for high and stable lithium storage
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作者 Dichao Wu Jiayuan Li +5 位作者 Yuying Zhao Ao Wang Gaoyue Zhang Jianchun Jiang Mengmeng Fan Kang Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期232-247,共16页
Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this ... Biomass‐derived carbon is a promising electrode material in energy storage devices.However,how to improve its low capacity and stability,and slow diffusion kinetics during lithium storage remains a challenge.In this research,we propose a“self‐assembly‐template”method to prepare B,N codoped porous carbon(BN‐C)with a nanosandwich structure and abundant pyridinic N‐B species.The nanosandwich structure can increase powder density and cycle stability by constructing a stable solid electrolyte interphase film,shortening the Li^(+) diffusion pathway,and accommodating volume expansion during repeated charging/discharging.The abundant pyridinic N‐B species can simultaneously promote the adsorption/desorption of Li^(+)/PF_(6)^(−) and reduce the diffusion barrier.The BN‐C electrode showed a high lithium‐ion storage capacity of above 1140 mAh g^(−1) at 0.05 A g^(−1) and superior stability(96.5% retained after 2000 cycles).Moreover,owing to the synergistic effect of the nanosandwich structure and pyridinic N‐B species,the assembled symmetrical BN‐C//BN‐C full cell shows a high energy density of 234.7Wh kg^(−1),high power density of 39.38 kW kg−1,and excellent cycling stability,superior to most of the other cells reported in the literature.As the density functional theory simulation demonstrated,pyridinic N‐B shows enhanced adsorption activity for Li^(+) and PF_(6)^(−),which promotes an increase in the capacity of the anode and cathode,respectively.Meanwhile,the relatively lower diffusion barrier of pyridinic N‐B promotes Li^(+) migration,resulting in good rate performance.Therefore,this study provides a new approach for the synergistic modulation of a nanostructure and an active site simultaneously to fabricate the carbon electrode material in energy storage devices. 展开更多
关键词 high cycling stability high energy density lithium‐ion batteries pyridinic N‐B species sandwich structure carbon nanosheet
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Highly Thermally Conductive and Structurally Ultra‑Stable Graphitic Films with Seamless Heterointerfaces for Extreme Thermal Management
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作者 Peijuan Zhang Yuanyuan Hao +17 位作者 Hang Shi Jiahao Lu Yingjun Liu Xin Ming Ya Wang Wenzhang Fang Yuxing Xia Yance Chen Peng Li Ziqiu Wang Qingyun Su Weidong Lv Ji Zhou Ying Zhang Haiwen Lai Weiwei Gao Zhen Xu Chao Gao 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期383-397,共15页
Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme altern... Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and safety.Here,we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks(LNS),which reveals a bubbling process characterized by“permeation-diffusion-deformation”phenomenon.To overcome this long-standing structural weakness,a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film(GF@Cu)with seamless heterointerface.This well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 K.Moreover,GF@Cu maintains high thermal conductivity up to 1088 W m^(−1)K^(−1)with degradation of less than 5%even after 150 LNS cycles,superior to that of pure GF(50%degradation).Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics. 展开更多
关键词 highly thermally conductive structurally ultra-stable Graphitic film Extreme thermal management Liquid nitrogen bubbling
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Effect of high-multiple water injection on rock pore structure and oil displacement efficiency
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作者 Xiao Lei Chunpeng Zhao +2 位作者 Qiaoliang Zhang Panrong Wang Runfu Xiong 《Energy Geoscience》 EI 2024年第1期234-238,共5页
Experimental methods,including mercury pressure,nuclear magnetic resonance(NMR)and core(wateroil)displacement,are used to examine the effects of high-multiple water injection(i.e.water injection with high injected por... Experimental methods,including mercury pressure,nuclear magnetic resonance(NMR)and core(wateroil)displacement,are used to examine the effects of high-multiple water injection(i.e.water injection with high injected pore volume)on rock properties,pore structure and oil displacement efficiency of an oilfield in the western South China Sea.The results show an increase in the permeability of rocks along with particle migration,an increase in the pore volume and the average pore throat radius,and enhanced heterogeneity after high-multiple water injection.Compared with normal water injection methods,a high-multiple water injection is more effective in improving the oil displacement efficiency.The degree of recovery increases faster in the early stage due to the expansion of the swept area,and the transition from oil-wet to water-wet.The degree of recovery increases less in the late stage due to various factors,including the enhancement of heterogeneity in the rocks.Considering both the economic aspect and the production limit of water flooding,it is recommended to adopt other technologies to further enhance oil recovery after 300 PV water injection. 展开更多
关键词 high multiple Water injection Rock permeability Pore structure Oil displacement efficiency
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A dendritic Cu/Cu_(2)O structure with high curvature enables rapid and efficient reduction of carbon dioxide to C_(2) in an H-cell
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作者 Lei shao Bochen Hu +3 位作者 Jinhui Hao Junjie Jin Weidong Shi Min Chen 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期144-153,共10页
Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is chall... Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is challenging because of the inefficient mass transfer of the catalyst and the presence of the hydrogen evolution reaction(HER).In this study,dendritic Cu/Cu_(2)O with abundant Cu^(0)/Cu^(+)interfaces and numerous dendritic curves was synthesized in a CO_(2)atmosphere,resulting in the high selectivity and current density of the C_(2)products.Dendritic Cu/Cu_(2)O achieved a C_(2)Faradaic efficiency of 69.8%and a C_(2)partial current density of 129.5 mA cm^(-2)in an H-cell.Finite element simulations showed that a dendritic structure with a high curvature generates a strong electric field,leading to a localized CO_(2)concentration.Additionally,DRT analysis showed that a dendritic struc-ture with a high curvature actively adsorbed the surrounding high concentration of CO_(2),enhancing the mass transfer rate and achieving a high current density.During the experiment,the impact of the electronic structure on the performance of the catalyst was investigated by varying the atomic ratio of Cu^(0)/Cu^(+) on the catalyst surface,which resulted in improved ethylene selectivity.Under the optimal atomic ratio of Cu^(0)/Cu^(+),the charge transfer resistance was minimized,and the desorption rate of the intermediates was low,favoring C_(2) generation.Density functional theory calculations indicated that the Cu^(0)/Cu^(+) interfaces exhibited a lower Gibbs free energy for the rate-determining step,enhancing C_(2)H_(4) formation.The Cu/Cu_(2)O catalyst also exhibited a low Cu d-band center,which enhanced the adsorption stability of *CO on the surface and facilitated C_(2)formation.This observa-tion explained the higher yield of C_(2) products at the Cu^(0)/Cu^(+) interface than that of H_(2) under rapid mass transfer.The results of the net present value model showed that the H-cell holds promising industrial prospects,contingent upon it being a catalyst with both high selectivity and high current density.This approach of integrating the structure and composition provides new insights for ad-vancing the CO_(2)RR towards high-current C_(2) products. 展开更多
关键词 Reduction of CO_(2) high current Dendritic structure Cu/Cu_(2)O H-cell
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Effect of Plastic Deformation on Microstructure and Properties of Cu-(1 wt%-6 wt%) Ag Alloy
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作者 茹亚东 ZHANG Zhongyuan +7 位作者 高召顺 ZHANG Ling ZUO Tingting XUE Jiangli TANG Zhixiang DA Bo LIU Yongsheng XIAO Liye 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期747-753,共7页
In the present study,the Cu-(1 wt%-6 wt%)Ag alloys were prepared by melting,forging and wire drawing.The effects of plastic deformation on microstructure evolution and properties of the alloys were investigated.The re... In the present study,the Cu-(1 wt%-6 wt%)Ag alloys were prepared by melting,forging and wire drawing.The effects of plastic deformation on microstructure evolution and properties of the alloys were investigated.The results show that non-equilibrium eutectic colonies exist in the Cu-(3 wt%-6 wt%)Ag alloy and no eutectic colonies in the 1 wt%-2 wt%Ag containing alloys.These eutectic colonies are aligned along the drawing direction and refined with the increase of draw ratio.Attributed to the refinement of eutectic colonies,the Cu-Ag alloy exhibits higher strength with the increase of draw ratio.The Cu-6Ag alloy exhibits excellent comprehensive properties with a strength of 930 MPa and a conductivity of 82%IACS when the draw ratio reaches 5.7. 展开更多
关键词 Cu-Ag alloy high strength and high conductivity microstructure eutectic structure strengthening mechanism
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Modification strategies improving the electrochemical and structural stability of high-Ni cathode materials
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作者 Yoon Bo Sim Hami Lee +1 位作者 Junyoung Mun Ki Jae Kim 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期185-205,共21页
With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving range.Consequently,several studies have been conducted on high-energy-density LiNi_(x)C... With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving range.Consequently,several studies have been conducted on high-energy-density LiNi_(x)Co_(y)Mn_(z)O_(2)cathodes.However,there is a limit to permanent performance deterioration because of side reactions caused by moisture in the atmosphere and continuous microcracks during cycling as the Ni content to express high energy increases and the content of Mn and Co that maintain structural and electrochemical stabilization decreases.The direct modification of the surface and bulk regions aims to enhance the capacity and long-term performance of high-Ni cathode materials.Therefore,an efficient modification requires a study based on a thorough understanding of the degradation mechanisms in the surface and bulk region.In this review,a comprehensive analysis of various modifications,including doping,coating,concentration gradient,and single crystals,is conducted to solve degradation issues along with an analysis of the overall degradation mechanism occurring in high-Ni cathode materials.It also summarizes recent research developments related to the following modifications,aims to provide notable points and directions for post-studies,and provides valuable references for the commercialization of stable high-energy-density cathode materials. 展开更多
关键词 high energy density high-Ni cathode materials Degradation structural stability Lithium-ion battery
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Highly Active Interfacial Sites in SFT-SnO_(2) Heterojunction Electrolyte for Enhanced Fuel Cell Performance via Engineered Energy Bands:Envisioned Theoretically and Experimentally
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作者 Sajid Rauf Muhammad Bilal Hanif +8 位作者 Faiz Wali Zuhra Tayyab Bin Zhu Naveed Mushtaq Yatao Yang Kashif Khan Peter D.Lund Martin Motola Wei Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期384-397,共14页
Extending the ionic conductivity is the pre-requisite of electrolytes in fuel cell technology for high-electrochemical performance.In this regard,the introduction of semiconductor-oxide materials and the approach of h... Extending the ionic conductivity is the pre-requisite of electrolytes in fuel cell technology for high-electrochemical performance.In this regard,the introduction of semiconductor-oxide materials and the approach of heterostructure formation by modulating energy bands to enhance ionic conduction acting as an electrolyte in fuel cell-device.Semiconductor(n-type;SnO_(2))plays a key role by introducing into p-type SrFe_(0.2)Ti_(0.8)O_(3-δ)(SFT)semiconductor perovskite materials to construct p-n heterojunction for high ionic conductivity.Therefore,two different composites of SFT and SnO_(2)are constructed by gluing p-and n-type SFT-SnO_(2),where the optimal composition of SFT-SnO_(2)(6∶4)heterostructure electrolyte-based fuel cell achieved excellent ionic conductivity 0.24 S cm^(-1)with power-output of 1004 mW cm^(-2)and high OCV 1.12 V at a low operational temperature of 500℃.The high power-output and significant ionic conductivity with durable operation of 54 h are accredited to SFT-SnO_(2)heterojunction formation including interfacial conduction assisted by a built-in electric field in fuel cell device.Moreover,the fuel conversion efficiency and considerable Faradaic efficiency reveal the compatibility of SFT-SnO_(2)heterostructure electrolyte and ruled-out short-circuiting issue.Further,the first principle calculation provides sufficient information on structure optimization and energy-band structure modulation of SFT-SnO_(2).This strategy will provide new insight into semiconductor-based fuel cell technology to design novel electrolytes. 展开更多
关键词 high ionic conductivity interfacial conduction modulated energy band structure p-n heterojunction SEMICONDUCTORS
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Effect of long-period stacking ordered structure on very high cycle fatigue properties of Mg-Gd-Y-Zn-Zr alloys
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作者 Xiangyu WANG Chao HE +3 位作者 Xue Li Lang LI Yongjie LIU Qingyuan WANG 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第8期2811-2822,共12页
Magnesium alloys with a long-period stacking ordered(LPSO)structure usually possess excellent static strength,but their fatigue behaviors are poorly understood.This work presents the effect of the LPSO structure on th... Magnesium alloys with a long-period stacking ordered(LPSO)structure usually possess excellent static strength,but their fatigue behaviors are poorly understood.This work presents the effect of the LPSO structure on the crack behaviors of Mg alloys in a very high cycle fatigue(VHCF)regime.The LPSO lamellas lead to a facet-like cracking process along the basal planes at the crack initiation site and strongly prohibit the early crack propagation by deflecting the growth direction.The stress intensity factor at the periphery of the faceted area is much higher than the conventional LPSO-free Mg alloys,contributing higher fatigue crack propagation threshold of LPSO-containing Mg alloys.Microstructure observation at the facets reveals a layer of ultrafine grains at the fracture surface due to the cyclic contact of the crack surface,which supports the numerous cyclic pressing model describing the VHCF crack initiation behavior. 展开更多
关键词 Fatigue crack initiation Long-period stacking ordered structure Mg alloys Ultrafine grains Very high cycle fatigue
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High-Throughput Growth of Hexagonal Boron Nitride Film Using Porous-Structure Isolation Layer
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作者 Ruitao Jia Fangzhu Qing Xuesong Li 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第3期45-51,共7页
Chemical vapor deposition is considered as the most hopeful method for the synthesis of large-area high-quality hexagonal boron nitride on the substrate of catalytic metal. However, the size the hexagonal boron nitrid... Chemical vapor deposition is considered as the most hopeful method for the synthesis of large-area high-quality hexagonal boron nitride on the substrate of catalytic metal. However, the size the hexagonal boron nitride films are limited to the size of growth chamber, which indicates a lower production efficiency. In this paper, the utilization efficiency of growth chamber is highly improved by alternately stacking multiple pieces of Cu foils and carbon fiber surface felt with porous structure. Uniform and continuous hexagonal boron nitride films are prepared on Cu foils through chemical vapor deposition utilizing ammonia borane as the precursor. This work develops a simple and practicable method for high-throughput preparation of hexagonal boron nitride films, which could contribute to the industrial application of hexagonal boron nitride. . 展开更多
关键词 Hexagonal Boron Nitride Chemical Vapor Deposition Porous structure Isolation Layer high Throughput
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Current situation and development trend of design methods for subgrade structure of high speed railways
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作者 Yangsheng Ye Degou Cai +3 位作者 Qianli Zhang Shaowei Wei Hongye Yan Lin Geng 《Railway Sciences》 2023年第3期289-309,共21页
Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed ... Purpose–This method will become a new development trend in subgrade structure design for high speed railways.Design/methodology/approach–This paper summarizes the structural types and design methods of subgrade bed for high speed railways in China,Japan,France,Germany,the United States and other countries based on the study and analysis of existing literature and combined with the research results and practices of high speed railway subgrade engineering at home and abroad.Findings–It is found that in foreign countries,the layered reinforced structure is generally adopted for the subgrade bed of high speed railways,and the unified double-layer or multi-layer structure is adopted for the surface layer of subgrade bed,while the simple structure is adopted in China;in foreign countries,different inspection parameters are adopted to evaluate the compaction state of fillers according to their respective understanding and practice,while in China,compaction coefficient,subsoil coefficient and dynamic deformation modulus are adopted for such evaluation;in foreign countries,the subgrade top deformation control method,the subgrade bottom deformation control method,the subsurface fill strength control method are mainly adopted in subgrade bed structure design of high speed railways,while in China,dynamic deformation control of subgrade surface and dynamic strain control of subgrade bed bottom layer is adopted in the design.However,the cumulative deformation of subgrade caused by train cyclic vibration load is not considered in the existing design methods.Originality/value–This paper introduces a new subgrade structure design method based on whole-process dynamics analysis that meets subgrade functional requirements and is established on the basis of the existing research at home and abroad on prediction methods for cumulative deformation of subgrade soil. 展开更多
关键词 high speed railway Subgrade engineering Subgrade bed structure Design method Existing research Development trend
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From Highly Structured E-Infinity Rings and Transfinite Maximally Symmetric Manifolds to the Dark Energy Density of the Cosmos 被引量:2
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作者 Mohamed S. El Naschie 《Advances in Pure Mathematics》 2014年第12期641-648,共8页
Starting from well established results in pure mathematics, mainly transfinite set theory, E-infinity algebra over operads, fuzzy manifolds and fuzzy Lie symmetry groups, we construct an exact Weyl scaling for the hig... Starting from well established results in pure mathematics, mainly transfinite set theory, E-infinity algebra over operads, fuzzy manifolds and fuzzy Lie symmetry groups, we construct an exact Weyl scaling for the highly structured E-infinity rings corresponding to E-infinity theory of high energy physics. The final result is an exact expression for the energy density of the cosmos which agrees with previous analysis as well as accurate cosmological measurements and observations, such as COBE, WMAP and Planck. The paper is partially intended as a vivid demonstration of the power of pure mathematics in physics and cosmology. 展开更多
关键词 highly structureD RINGS E-INFINITY Loop Spaces high ENERGY Physics Dark ENERGY Einstein Relativity Fractal-Cantorian Spacetime Nonlinear Dynamics Quantum Chaos
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Highly stable aqueous rechargeable Zn-ion battery:The synergistic effect between NaV_(6)O_(15) and V_(2)O_(5) in skin-core heterostructured nanowires cathode 被引量:2
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作者 Lanlan Fan Zhenhuan Li +1 位作者 Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期25-33,共9页
The aqueous rechargeable Zn-ion batteries based on the safe,low cost and environmental benignity aqueous electrolytes are one of the most compelling candidates for large scale energy storage applications.However,pursu... The aqueous rechargeable Zn-ion batteries based on the safe,low cost and environmental benignity aqueous electrolytes are one of the most compelling candidates for large scale energy storage applications.However,pursuing suitable insertion materials may be a great challenge due to the strong electrostatic interaction between Zn^(^(2+))and cathode materials.Hence,a novel NaV_(6)O_(15)/V_(2)O_(5) skin-core heterostructure nanowire is reported via a one-step hydrothermal method and subsequent calcination for high-stable aqueous Zn-ion batteries(ZIBs).The NaV_(6)O_(15)/V_(2)O_(5) cathode delivers high specific capacity of 390 m Ah/g at 0.3 A/g and outstanding cycling stability of 267 m Ah/g at 5 A/g with high capacity retention over 92.3%after 3000 cycles.The superior electrochemical performances are attributed to the synergistic effect of skin-core heterostructured NaV_(6)O_(15)/V_(2)O_(5),in which the sheath of NaV_(6)O_(15) possesses high stability and conductivity,and the V_(2)O_(5) endows high specific capacity.Besides,the heterojunction structure not only accelerates intercalation kinetics of Zn^(2+)transport but also further consolidates the stability of the layers of V_(2)O_(5) during the cyclic process.This work provides a new perspective in developing feasible insertion materials for rechargeable aqueous ZIBs. 展开更多
关键词 Aqueous zinc ion battery Heterojunction structure high specific capacity Stable long cycle Synergistic effect
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Atomic structure and collision dynamics with highly charged ions 被引量:1
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作者 Xinwen Ma Shaofeng Zhang +11 位作者 Weiqiang Wen Zhongkui Huang Zhimin Hu Dalong Guo Junwen Gao Bennaceur Najjari Shenyue Xu Shuncheng Yan Ke Yao Ruitian Zhang Yong Gao Xiaolong Zhu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期13-40,共28页
The research progresses on the investigations of atomic structure and collision dynamics with highly charged ions based on the heavy ion storage rings and electron ion beam traps in recent 20 years are reviewed.The st... The research progresses on the investigations of atomic structure and collision dynamics with highly charged ions based on the heavy ion storage rings and electron ion beam traps in recent 20 years are reviewed.The structure part covers test of quantum electrodynamics and electron correlation in strong Coulomb field studied through dielectronic recombi-nation spectroscopy and VUV/x-ray spectroscopy.The collision dynamics part includes charge exchange dynamics in ion-atom collisions mainly in Bohr velocity region,ion-induced fragmentation mechanisms of molecules,hydrogen-bound and van de Waals bound clusters,interference,and phase information observed in ion-atom/molecule collisions.With this achievements,two aspects of theoretical studies related to low energy and relativistic energy collisions are presented.The applications of data relevant to key atomic processes like dielectronic recombination and charge exchanges involving highly charged ions are discussed.At the end of this review,some future prospects of research related to highly charged ions are proposed. 展开更多
关键词 highly charged ion atomic structure collision dynamics quantum electrodynamics fragmentation mechanisms relativistic effects electron correlation
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A highly stable membrane with hierarchical structure for wide pH range flow batteries
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作者 Jing Hu Donglei Yu +3 位作者 Tianyu Li Huamin Zhang Zhizhang Yuan Xianfeng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期80-86,共7页
A membrane with high stability and ion conductivity in wide pH range is essential for energy storage devices.Here,we report a novel membrane with hierarchical core-shell structure,which demonstrates high stability and... A membrane with high stability and ion conductivity in wide pH range is essential for energy storage devices.Here,we report a novel membrane with hierarchical core-shell structure,which demonstrates high stability and ion conductivity,simultaneously under a wide pH range applications.Spectral characterizations and theoretical calculation indicate that the non-solvent induces the chain segment configuration and eventually leads to polymer-polymer phase separation,thus forming hierarchical porous core-shell structure.Benefiting from this structure,an acidic vanadium flow battery(VFB)with such a membrane shows excellent performance over 400 cycles with an energy efficiency(EE)of above 81%at current density of 120 mA cm^(-2) and an alkaline zinc-iron flow battery(AZIFB)delivers a cycling stability for more than 200 cycles at 160 mA cm^(-2),along with an EE of above 82%.This paper provides a cost-effective and simple way to fabricate membranes with high performance for variety of energyrelated devices. 展开更多
关键词 Energy storage Wide pH range flow batteries Hierarchical porous membrane Core-shell structure high stability
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RECALESCENCE BEHAVIOUR AND SOLIDIFICATION STRUCTURE OF HIGHLY UNDERCOOLED Ni-32.5%Sn EUTECTIC ALLOY
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作者 Wei Bingbo, Yang Gencang and Zhou YaoheNorthwestern Polytechnical University 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1991年第3期312-319,共8页
Large undercoolings up to 395K (0.28TE) are obtained for 15g samples of Ni-32.5%Sn eutectic alloy by superheating the alloy melt to 108-700K above its eutectic temperature and consequently destroying most of the inher... Large undercoolings up to 395K (0.28TE) are obtained for 15g samples of Ni-32.5%Sn eutectic alloy by superheating the alloy melt to 108-700K above its eutectic temperature and consequently destroying most of the inherent heterogeneous nuclei. The recalcscence phenomenon and its dependence on undercooling and on crystal nuclcation and growth, as well as its relationship to solidification microstructures are studied. The crystalli/ation fraction during recalcsccnce is also calculated. Experiments reveal that recalcscence degree increases with undercooling when the latter is below a certain critical value∧Te, but it decreases as undercooling increases above A 7'( (under present conditions∧Te= 245K, i. c. 0.17TE). The greater the recalescencc degree, the larger the proportion of anomalous eutectic in solidified structures. It is inferred that anomalous eutectic is the product of rapid solidification while lamellar eutectic forms at much slower nuclcation rate and growth velocity. 展开更多
关键词 SN TE RECALESCENCE BEHAVIOUR AND SOLIDIFICATION structure OF highly UNDERCOOLED Ni-32.5%Sn EUTECTIC ALLOY NI
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ISOLATION AND STRUCTURE DETERMINATION OF LAMIOPHLOMICL C,A NEW HIGHLY OXYGENATED IRIDOID FROM LAMIOPHLOMIS ROTATA
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作者 Jin Hai YI Chi Chang ZHONG Ze Yuan LUO Sichuan Institute of Chinese Materia Medica,Chongqing,630065Zhuo Yin XIAO West China University of Medical Soience,Chengdu,610041Bin WU Qi Tai ZHENG Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing,100050 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期23-24,共2页
A new highly oxygenated iridoid,lamiophlomiol C,was isolated from the roots of Lamiophlomis rotata and its structure was elucidated by spectrosoopic techniques and X-ray diffraction.
关键词 ISOLATION AND structure DETERMINATION OF LAMIOPHLOMICL C A NEW highly OXYGENATED IRIDOID FROM LAMIOPHLOMIS ROTATA
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Structure uniformity and limits of grain refinement of high purity aluminum during multi-directional forging process at room temperature 被引量:6
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作者 朱庆丰 李磊 +3 位作者 班春燕 赵志浩 左玉波 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1301-1306,共6页
The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinemen... The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinement limitation with very high strains. The results show that the fine grain zone in the center of sample expands gradually with the increase of forging passes. When the forging passes reach 6, an X-shape fine grain zone is initially formed. With a further increase of the passes, this X-shape zone tends to spread the whole sample. Limitation in the structural refinement is observed with increasing strains during multi-forging process at the room temperature. The grains size in the center is refined to a certain size (110 μm as forging passes reach 12, and there is no further grain refinement in the center with increasing the forging passes to 24. However, the size of the coarse grains near the surface is continuously decreased with increasing the forging passes to 24. 展开更多
关键词 multi-directional forging high purity aluminum structure uniformity grain refinement
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OBSERVER/FILTER STRUCTURE BASED ADAPTIVE FRICTION COMPENSATION FOR HIGH PRECISION TURNTABLE 被引量:3
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作者 王忠山 苏宝库 王毅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期113-120,共8页
Two adaptive friction compensation schemes are developed for a high precision turntable system with nonlinear dynamic friction to handle two types of parametric uncertainties in the friction. Both schemes utilize a no... Two adaptive friction compensation schemes are developed for a high precision turntable system with nonlinear dynamic friction to handle two types of parametric uncertainties in the friction. Both schemes utilize a nonlinear observer/filter structure to compensate for uncertainties in corresponding friction parameters associated with the turntable system. Moreover, in the second scheme, adjustable gains are introduced into the dual nonlin- ear filters and they can be tuned to improve the position tracking performance. In both cases, a Lyapunov-like argument is provided for the global asymptotic stability of the closed-loop system. Simulation results demonstrate the effectiveness of the proposed schemes. 展开更多
关键词 FRICTION wave filters adaptive friction compensation high precision turntable observer/filter structure
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