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Strengthening of ultrasonic welded FeCrAl alloy/SCFR-PA6 metal/CFRTP joint via surface texturing design
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作者 Tingting ZHANG Xingrun AN +2 位作者 Shengtao ZHANG Yongzhen LIANG Wei ZHOU 《Chinese Journal of Aeronautics》 2025年第12期544-557,共14页
The joining of Fe Cr Al alloy and Carbon Fiber Reinforced Thermoplastic Composites(CFRTP)presents a promising strategy for the development of lightweight and structurally reliable components.In this study,ultrasonic w... The joining of Fe Cr Al alloy and Carbon Fiber Reinforced Thermoplastic Composites(CFRTP)presents a promising strategy for the development of lightweight and structurally reliable components.In this study,ultrasonic welding,noted for its efficiency and environmentally sustainable characteristics,was employed to examine systematically examine the impact of surface texturing on joint performance.Two distinct categories of Fe Cr Al surface textures,discrete unit patterns and continuous groove structures,were created and subsequently welded with Short Carbon Fiber Reinforced Polyamide 6(SCFR-PA6).The wettability of molten SCFR-PA6 on the textured surfaces and the bonding strength of the resulting joints were evaluated,alongside comprehensive analyses of fracture surfaces and interfacial morphologies.The findings indicated that continuous groove textures significantly improved wettability in comparison to discrete unit textures.Notably,joints with continuous grid-like texturing exhibited complete resin infiltration and achieved the highest bonding strength of 18.26 MPa.This enhancement is primarily attributed to the continuous groove structures,which facilitate unobstructed resin flow and promote the effective extrusion of carbon fibers.A novel reinforcement strategy for metal/CFRTP joints is proposed,wherein interfacial texture design is used to regulate temperature distribution and resin flow dynamics during welding.These results offer critical insights into the optimization of metal/CFRTP joint design and manufacturing processes for advanced structural applications. 展开更多
关键词 Bonding interface FeCrAl alloy metal/cfrtp joint Texturing Welding
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Self-trapped Excitons in Metal Halides for Lighting Applications
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作者 ZHANG Xiang LIU Nian +1 位作者 LUO Jiajun TANG Jiang 《发光学报》 北大核心 2026年第3期423-435,共13页
Metal halides have attracted worldwide attention as exceptional optoelectronic materials.Over the past decade,research on metal halides has yielded remarkable progress,and their color-conversion applications have show... Metal halides have attracted worldwide attention as exceptional optoelectronic materials.Over the past decade,research on metal halides has yielded remarkable progress,and their color-conversion applications have shown considerable promise for commercialization.With the reporting of self-trapped exciton(STE)emission in perovskites,the application of metal halides as broadband emitting materials in the lighting field has gained increas-ing interest.Herein,we provide a comprehensive review of metal halide STE emitters,especially for lighting applications.We begin with highlighting the ideal spectral characteristics and corresponding performance metrics for lighting.This is followed by a systematic summary of the mechanisms,optimization strategies,and recent advances of STE emission in metal halides.Finally,we outline the major challenges and prospective trends for metal halide STE emitters.This review aims to offer valuable insights into metal halide STE emitters and their lighting applications for facilitating the future commercialization. 展开更多
关键词 self-trapped exciton metal halide LIGHTING optoelectronic applications
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A standardized dataset of CO-TPD spectra on transitionmetal single-crystal surfaces
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作者 YANG Lin WU Jianghong WANG He 《燃料化学学报(中英文)》 北大核心 2026年第4期180-190,共11页
Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.Howeve... Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.However,the majority of existing TPD data is accessible in the form of published images,which lacks structured and quantitative datasets.This constrains its utility for rigorous quantitative analysis and computational modelling.Using carbon monoxide(CO)which is a widely adopted probe molecule,a curated and standardized dataset of CO-TPD is constructed,encompassing 14 transition-metal single-crystal surfaces,including copper(Cu)and ruthenium(Ru).By systematically extracting numerical data points from published spectra and applying normalization,essential spectral features such as peak shape are fully preserved.The dataset also documents relevant experimental parameters,including heating rates,and was developed using a standardized protocol for data collection and quality control.This resource serves as both a reference library to support the deconvolution of TPD spectra from complex catalysts and an experimental benchmark for calibrating parameters in theoretical models.By providing a reliable and accessible data function,this work advances the microscopic understanding and the rational design of catalyst active centers. 展开更多
关键词 CO-TPD standardized dataset transition metal single-crystal surfaces
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Pollution Characteristics and Sources of Heavy Metal in the Soil Around a Concentrated Lead and Zinc Mining Area in Guangxi
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作者 LU Yuqiu TANG Xiaohui +5 位作者 XIN Meifen HUANG Yanhong LI Yang WU Hao LUO Dongyuan ZHOU Lang 《有色金属(中英文)》 北大核心 2026年第2期392-411,共20页
39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.Ar... 39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas. 展开更多
关键词 mining area soil heavy metals pollution characteristics risk assessment source apportionment
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Recent progress in the modification of copper current collectors for lithium metal batteries
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作者 Cheng Zhang Qitao Shi +7 位作者 Luwen Li Jiaqi Wang Zhipeng Wang Alicja Bachmatiuk Chen Lu Yanbin Shen Ruizhi Yang Mark H.Rümmeli 《Journal of Energy Chemistry》 2026年第3期848-867,共20页
Lithium metal batteries(LMBs)are promising candidates for next-generation high-energy-density storage devices.However,an unstable lithium metal anode poses significant issues that critically compromise battery safety ... Lithium metal batteries(LMBs)are promising candidates for next-generation high-energy-density storage devices.However,an unstable lithium metal anode poses significant issues that critically compromise battery safety and cycle life,including lithium dendrite formation,solid electrolyte interphase degradation,dead lithium accumulation,and substantial volume fluctuations during cycling.These problems can be addressed by regulating lithium deposition and suppressing side reactions through the modification of copper current collectors using three classes of materials:metal and metal oxide,carbon,and polymer materials.This review comprehensively examines recent advances in the application of these materials as current collector coatings.Particularly,their distinct roles in the lithium deposition process are analyzed to understand how they mitigate the issues associated with the lithium metal anode.Furthermore,their inherent limitations are considered to inform future research directions.While each class of materials offers specific advantages,multifunctionality is required to effectively regulate lithium deposition.In prospect,a novel composite copper current collector design that integrates the merits of the aforementioned advanced materials is proposed.The insights from this review provide valuable guidance for the rational design of modified copper current collectors,which would significantly improve the safety and cycle life of LMBs and advance their commercialization. 展开更多
关键词 Lithium metal battery metal metal oxide CARBON POLYMER Composite current collector
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Nano/micro-engineered metallic flexible electrodes:advancing the era of epidermal electronics
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作者 Haoran Zhu Haogeng Liu +1 位作者 Jeong Ho Cho Gui-Shi Liu 《International Journal of Extreme Manufacturing》 2026年第1期65-118,共54页
Metals,indispensable since the Bronze Age,remain pivotal in modern technologies due to their exceptional properties and versatility.Beyond traditional machining,advanced nano/micro-machining techniques enable the fabr... Metals,indispensable since the Bronze Age,remain pivotal in modern technologies due to their exceptional properties and versatility.Beyond traditional machining,advanced nano/micro-machining techniques enable the fabrication of metallic nano/micro structures with high precision in shape,size,and pattern.These structures endow flexible electrodes with outstanding electrical,mechanical,optical,and electrochemical performance,enabling growing applications in flexible optoelectronics,epidermal electronics,energy harvesting,and biochemical sensing.This review provides a comprehensive overview of the fabrication strategies for flexible electrodes made from metal meshes,metal nanowires,and liquid metals.The current advancements,existing challenges,and emerging technologies are systematically discussed.Furthermore,the progression toward ultra-thin,soft epidermal electrodes is explored,with an emphasis on novel in situ and transfer fabrication methods.We examine the underlying mechanisms,performance indicators,and their integration for on-skin applications,including bioelectric sensing,electrical stimulation,and energy harvesting.Finally,we highlight the remaining challenges in performance improvement and industrialization of flexible and epidermal electrodes,along with future opportunities for integrating multimodal systems and leveraging artificial intelligence to enhance their functionalities. 展开更多
关键词 metal mesh metal nanowire liquid metal flexible electrode soft epidermal electrode
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Research Progress on Process Optimization and Performance Control of Additive Manufacturing for Refractory Metals
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作者 Lu Durui Song Suocheng Lu Bingheng 《稀有金属材料与工程》 北大核心 2026年第2期345-364,共20页
Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durabili... Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durability,and corrosion resistance.These metals have body-centered cubic crystal structure,characterized by limited slip systems and impeded dislocation motion,resulting in significant low-temperature brittleness,which poses challenges for the conventional processing.Additive manufacturing technique provides an innovative approach,enabling the production of intricate parts without molds,which significantly improves the efficiency of material usage.This review provides a comprehensive overview of the advancements in additive manufacturing techniques for the production of refractory metals,such as W,Ta,Mo,and Nb,particularly the laser powder bed fusion.In this review,the influence mechanisms of key process parameters(laser power,scan strategy,and powder characteristics)on the evolution of material microstructure,the formation of metallurgical defects,and mechanical properties were discussed.Generally,optimizing powder characteristics,such as sphericity,implementing substrate preheating,and formulating alloying strategies can significantly improve the densification and crack resistance of manufactured parts.Meanwhile,strictly controlling the oxygen impurity content and optimizing the energy density input are also the key factors to achieve the simultaneous improvement in strength and ductility of refractory metals.Although additive manufacturing technique provides an innovative solution for processing refractory metals,critical issues,such as residual stress control,microstructure and performance anisotropy,and process stability,still need to be addressed.This review not only provides a theoretical basis for the additive manufacturing of high-performance refractory metals,but also proposes forward-looking directions for their industrial application. 展开更多
关键词 refractory metals additive manufacturing mechanical properties microstructure evolution optimization of printing process
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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Stabilizing the Anode and Cathode Interface Synchronously via Electrolyte-Triggered Hydrogel Interphase for Zinc Metal Batteries
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作者 Xinze Cai Xin Li +5 位作者 Jiahui Liang Jiazhen Qiu Wenkuo Lin Chunlong Dai Zifeng Lin Jiangqi Zhao 《Nano-Micro Letters》 2026年第6期717-731,共15页
The advancement of aqueous zinc metal batteries(ZMBs)is constrained by intrinsic interfacial issues in aqueous electrolyte systems.Here,using numerical simulation,we decipher the multi-scale causes of interfacial inst... The advancement of aqueous zinc metal batteries(ZMBs)is constrained by intrinsic interfacial issues in aqueous electrolyte systems.Here,using numerical simulation,we decipher the multi-scale causes of interfacial instability,elucidating the synergistic effect of macroscopic ineffective regions and microscopic passivation.Based on the analysis,we develop an electrolyte-triggered interphase construction strategy to resolve the interfacial failure.This strategy couples the in situ formation of hydrogel interphase on both the anode and cathode with the electrolyte filling process,thereby(1)facilitating contact between electrodes and the separator;(2)promoting anode reversibility through inducing a bilayer SEI that enhances Zn^(2+)desolvation kinetics and blocks electron tunneling;(3)ensuring long-term cathode cycling stability via restricting the irreversible dissolution of MnO_(2)and side-reactions.The resultant Zn metal anode exhibited a near-unity Coulombic efficiency(99.5%)for Zn plating/stripping at an extremely low current density of 0.1 mA cm^(-2)and the Zn/MnO_(2)full cell sustained 2000 full-duty-cycles with an exceptionally low decay rate of 0.0051%per-cycle.This work unlocks an alternative angle for promoting practical ZMB s toward more sustainable energy storage systems. 展开更多
关键词 Zinc metal batteries Aqueous electrolyte metal anode interfacial engineering Solid-electrolyte interphase
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Cr-Substitution-Driven Correlation Enhancement and Hund's Metallicity in CsV_(3-x)Cr_(x)Sb_(5)
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作者 Guiyan Dong Zihao Huo +3 位作者 Wenxuan Chen Tiancheng Ma Jialiang Cai Defang Duan 《Chinese Physics Letters》 2026年第3期283-293,共11页
The Kagome metal CsV3Sb5 transitions from a weakly correlated state to a strongly correlated state upon Cr substitution;however,the mechanism driving this enhancement remains an open question.Here,we employed a combin... The Kagome metal CsV3Sb5 transitions from a weakly correlated state to a strongly correlated state upon Cr substitution;however,the mechanism driving this enhancement remains an open question.Here,we employed a combination of density functional theory and dynamical mean-field theory(DFT+DMFT)to systematically investigate the evolution of electronic correlations in the CsV_(3−x)Cr_(x)Sb_(5)(x=0,1,and 3)series.Our calculations revealed that Cr doping drives the system into a strongly correlated Hund’s metal phase,which is characterized by significant and orbital-dependent enhancements in the quasiparticle effective masses and electronic scattering rates.We trace the origin of this transition to the doping-induced shift from low-to high-spin atomic configurations.This preference for high-spin states,which is promoted by near-half-filling of the Cr-d orbitals,induces a pronounced orbital blocking effect that strengthens the correlations.Our findings establish that Hund’s coupling is the decisive factor governing the rich correlation physics in the CsV_(3−x)Cr_(x)Sb_(5) family,providing a tunable platform for exploring Hund’s metallicity. 展开更多
关键词 hund s metal pha dynamical mean field theory density functional theory electronic correlations evolution electronic correlations hunds metallicity kagome metal csv sb cr substitution
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Linker fluorinated metal-organic frameworks enhancing ion conduction for fast-charging lithium metal batteries
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作者 Bingqi Luo Zeru Wang +4 位作者 Xiaotao Zhu Jieyan Li Huixian Yang Bing Guo Ke Wang 《Journal of Energy Chemistry》 2026年第2期749-760,I0016,共13页
Composite solid-state electrolytes incorporating metal-organic frameworks(MOFs)demonstrate tremendous potential for ameliorating Li^(+)conduction in lithium metal batteries.However,their practical application is hinde... Composite solid-state electrolytes incorporating metal-organic frameworks(MOFs)demonstrate tremendous potential for ameliorating Li^(+)conduction in lithium metal batteries.However,their practical application is hindered by low ionic co nductivity and unstable Li^(+)transport at the electrode interfaces.To overcome these challenges,a previously unreported family of indium based MOFs(In-BDC-F_(x),x=0,4,6)with tunable fluorine content was synthesized and integrated into PVDF-HFP matrices to construct highperformance quasi-solid-state electrolytes.By systematically modulating linker fluorination,a bifunctional enhancement mechanism is revealed:fluorinated indium centers simultaneously suppress polymer crystallinity and establish preferential Li^(+)conduction pathways.Remarkably,In-BDC-F_(6) manifests exceptional synergistic interactions between-CF_(3) functionalities and indium coordination sites,amplifying Lewis acidity to facilitate LiTFSI dissociation and TFSI-immobilization,culminating in homogeneous LiF-enriched solid electrolyte interphases.The optimized electrolyte demonstrates compelling electrochemical performance:ionic conductivity of 9.68×10^(-4) S cm^(-1),Li^(+)transference number of 0.70,and electrochemical stability window of 4.96 V.Li‖Li symmetric cell demonstrated a critical current density of 3.5 mA cm^(-2) and stable plating/stripping for over 1000 h at 0.2 mA cm^(-2),while LiFePO_(4)‖Li cells retain96.66%capacity after 1300 cycles at 10C,underscoring the transformative potential of fluorinated MOF architectures in fast-charging solid-state batteries. 展开更多
关键词 Quasi-solid-state electrolyte metal–organic frameworks Lithium metal batteries
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Unraveling lithium metal plating behavior on cobalt-decorated 3D carbon textile for high-energy-density lithium metal batteries
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作者 Hongjung Kim Changshin Jo 《Journal of Energy Chemistry》 2026年第3期264-276,共13页
Lithium metal anodes are promising for next-generation high-energy batteries,but their practical application is limited by safety issues arising from uncontrolled Li metal growth.To address these challenges,we report ... Lithium metal anodes are promising for next-generation high-energy batteries,but their practical application is limited by safety issues arising from uncontrolled Li metal growth.To address these challenges,we report a scalable approach to fabricate flexible,free-standing 3D carbon textiles derived from low-cost cellulose textiles,uniformly decorated with cobalt particles(Co@c-Textile).The work function difference between cobalt particles and carbon induces a redistribution of surface charge,enabling the synergistic combination of cobalt and defective carbon to enhance lithiophilicity and promote uniform Li growth through accelerate surface diffusion.Detailed analyses further reveal that lithium preferentially plates not directly on the cobalt particles,but on the adjacent carbon regions,eventually encapsulating the cobalt and growing uniformly across the carbon surface.As a result,the Co@c-Textile@Li anode exhibits prolonged and stable cycling over 700 h in symmetric cells,along with improved Li+transport kinetics.Furthermore,in full-cells with Li Fe PO_(4)(LFP)cathodes,it delivers over 90%capacity retention at both1C and 4C,and also demonstrates excellent stability under high-voltage conditions with Ni-rich cathodes.These findings clarify the role of transition metal/carbon composites in directing uniform Li plating and provide a viable strategy for designing advanced carbon-hosted Li metal anodes. 展开更多
关键词 Li metal batteries Carbon textiles Carbon frameworks Free-standing carbon materials MOF Lithiophilic chemistry metal catalysts
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Metallothionein and neurodegenerative diseases
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作者 Yufeng Cheng Yujia Zhao +1 位作者 Ce Chen Feng Zhang 《Neural Regeneration Research》 2026年第8期3449-3461,共13页
Neurodegenerative diseases,which mainly include Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,Wilson’s disease,and Huntington’s disease,are a group of disorders characterized by loss of neu... Neurodegenerative diseases,which mainly include Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,Wilson’s disease,and Huntington’s disease,are a group of disorders characterized by loss of neurons in the brain and spinal cord.However,the underlying pathogenetic mechanisms of these disorders remain unclear.The metal ion hypothesis is considered a possible cause of a variety of neurodegenerative diseases.This hypothesis posits that the homeostatic imbalance of metal ions leads to oxidative stress,neuroinflammation,excessive aggregation of pathological proteins,and other serious consequences in neurons.The powerful endogenous metal ion chelator metallothionein plays an important role in regulating metal ion homeostasis to alleviate neurodegenerative diseases.This article provides an overview of the pathogenesis of neurodegenerative diseases in relation to metal ions such as copper,iron,and zinc and the contribution of metallothionein to the regulation of metal ion homeostasis.The review focuses on the role of metal ions in the course of neurodegenerative diseases and the molecular mechanisms through which endogenous metallothionein ameliorates metal ion overload to alleviate neurodegenerative diseases.A thorough understanding of these molecular mechanisms can provide a theoretical foundation for the development of new therapeutic strategies,with the aim of more effectively treating these devastating diseases in the future. 展开更多
关键词 Alzheimer’s disease amyotrophic lateral sclerosis Huntington’s disease metal chelator metal homeostasis metal ion metalLOTHIONEIN neurodegenerative diseases Parkinson’s disease Wilson’s disease
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Charge Disproportionation Driven Polar Magnetic Metallic Double-Layered Perovskite Sr_(3)Co_(2)O_(7)
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作者 Hong-Fei Huang Houssam Sabri +1 位作者 Jiadong Zang Jie-Xiang Yu 《Chinese Physics Letters》 2026年第3期240-253,共14页
Strong coupling among spontaneous structural symmetric breaking,magnetism,and metallicity in an intrinsic polar magnetic metal can give rise to novel physical phenomena and holds great promise for applications in spin... Strong coupling among spontaneous structural symmetric breaking,magnetism,and metallicity in an intrinsic polar magnetic metal can give rise to novel physical phenomena and holds great promise for applications in spintronics.Here,we elucidate the mechanism of magnetic polarity in the recently discovered polar metal Sr_(3)Co_(2)O_(7).Our first-principles calculations reveal that both the spontaneous polar displacements and the metallicity originate from charge disproportionation of Co ions.This is characterized by an inverted ligand-field splitting of the Co t_(2g) orbitals at one site,while the metallic behavior is preserved by the t_(2g) orbitals at both sites.Charge disproportionation,which originates from the on-site Hubbard U interaction,stabilizes the asymmetric phase.We thus propose that in related transition metal oxides,charge disproportionation within specific orbitals can concurrently drive metallicity and polarity,enabling strong coupling between these properties.More remarkably,this mechanism allows for the coexistence of magnetism,as evidenced in Sr_(3)Co_(2)O_(7).Our findings highlight a promising avenue for realizing polar magnetic metals and provide a new design principle for exploring multifunctional materials. 展开更多
关键词 mechanism magnetic polarity charge disproportionation polar magnetic metal co ionsthis structural symmetric breakingmagnetismand polar metal spontaneous polar displacements
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In situ directly grown carboxylated UiO-66-infused separator as a comprehensive regulator of Zn solvation structure enabling dendrite-and corrosion-free Zn metal anode
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作者 Jung Bin Park Bo Keun Park +4 位作者 Ji Woo Han Sung Joon Park Seungyeop Kang Dong-Joo Yoo Ki Jae Kim 《Journal of Energy Chemistry》 2026年第1期634-644,I0014,共12页
Aqueous zinc ion batteries(AZIBs)are considered promising candidates owing to their inherent safety and low cost.However,the conventional glass fiber(GF)separator used in AZIBs suffers from poor physicochemical proper... Aqueous zinc ion batteries(AZIBs)are considered promising candidates owing to their inherent safety and low cost.However,the conventional glass fiber(GF)separator used in AZIBs suffers from poor physicochemical properties,leading to uncontrolled zinc(Zn)dendrite formation and undesirable side reactions.To address these limitations and enhance the electrochemical performance of AZIBs,a precisely designed functional separator is developed by incorporating UiO-66-(COOH)_(2)into a poly(vinylidene fluoride)(PVDF)framework(U-PVDF)via a direct in situ growth method.This approach enables uniform distribution of UiO-66-(COOH)_(2)both on the surface and within the PVDF backbone,without increasing separator thickness.Owing to the strong interaction between Zn^(2+)and the abundant carboxyl groups in UiO-66-(COOH)_(2),the U-PVDF separator regulates the Zn^(2+)solvation structure toward a contact ion pair-dominated structure by reducing coordinated water molecules,which effectively mitigates water-induced parasitic reactions and promotes compact Zn deposition.Consequently,a Zn/Zn symmetric cell employing the U-PVDF separator demonstrates superior cycling stability over 1500 cycles without internal short-circuiting at a current density of 6 mA cm^(−2)and an areal capacity of 2 mAh cm^(−2).Moreover,Zn/NaV_(3)O_(8)·xH_(2)O(NVO)cell with the U-PVDF separator exhibits markedly improved cyclability and rate performance compared with those using conventional GF separator. 展开更多
关键词 Zn metal anode metal organic framework Zn2+solvation structure Zn dendrites Aqueous zinc ion battery Separator modification
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Evaluation of Heavy Metal Contamination in Soils of Vegetable Cultivation Bases in Zunyi City
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作者 Zhangyu ZHAO Wenzhao LI +5 位作者 Xiong YAN Xiao WANG Pingfan WU Meiju WANG Shoumei WU Nana WANG 《Asian Agricultural Research》 2026年第1期33-35,共3页
[Objectives]To analyze the current status of heavy metal contamination in soils of vegetable cultivation bases located in Huichuan District,Zunyi City.[Methods]Soil samples from various depths within the vegetable cul... [Objectives]To analyze the current status of heavy metal contamination in soils of vegetable cultivation bases located in Huichuan District,Zunyi City.[Methods]Soil samples from various depths within the vegetable cultivation bases of Guanba Village,Sidu Village,and Banqiao Village in Huichuan District,Zunyi City,were selected as the subjects of this study.The concentrations of five heavy metals,including lead(Pb),mercury(Hg),cadmium(Cd),arsenic(As),and chromium(Cr),were measured at different soil depths.The Nemerow comprehensive pollution index method was employed to assess heavy metal contamination,and the analysis was conducted in accordance with the farmland environmental quality evaluation standards for edible agricultural products.[Results]The concentrations of Cd and As at the sample collection sites were relatively elevated.The pollution level of Cd reached grade III or above,indicating moderate contamination in certain topsoil areas.Most As concentrations corresponded to grade II and grade III pollution levels.In contrast,Hg,Pb,and Cr concentrations remained within the safety standards established for agricultural products.However,Cd and As levels predominantly surpassed these safety thresholds.Notably,Guanba Village and Sidu Village exhibited significant pollution levels,warranting comprehensive investigations into the sources of contamination.[Conclusions]This study offers valuable insights for advancing the sustainable development of local agriculture and for the prevention and management of soil contamination. 展开更多
关键词 Heavy metal contamination Nemerow index VEGETABLE
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The sequestration of metal nanoparticles in the liver:A trade-off between density and degradability
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作者 Junjie Ma Li Zeng +14 位作者 Yaquan Liu Shunhao Wang Min Li Linlin Yao Gang Tang Ziniu Wang Jiexia Cheng Qi Wu Guangxuan Wang Chunzhen Shi Liqun Chen Runzeng Liu Jie Gao Guangbo Qu Guibin Jiang 《Journal of Environmental Sciences》 2026年第2期682-689,共8页
The widespread use and casual disposal of nanoproducts increase human exposure to nanoparticles(NPs),posing potential health risks.When coming into contact with biofluid,NPs passively move in the bloodstream and reach... The widespread use and casual disposal of nanoproducts increase human exposure to nanoparticles(NPs),posing potential health risks.When coming into contact with biofluid,NPs passively move in the bloodstream and reach target organs and cells.The nano-bio interactions,distribution,and fate of NPs are highly dependent on their physicochemical properties after direct exposure into the systemic circulation.In this study,silver nanoparticles(AgNPs)and gold nanoparticles(AuNPs)with the same size,shape,surface chemistry,and particle number but different densities were co-exposed to mice to explore their blood circulation and liver accumulation.The co-exposure avoids the individual differences in a single-material exposure model.Post-exposure,Au remained longer in the bloodstream than Ag,while 92.2%of the injected dose(%ID)of Ag accumulated in the liver compared to 78.0%for Au.Over a span of 3 to 72 h,Ag content in bloodstream increased while Au was undetectable.In the liver,the%ID of Ag sharply decreased to 9.4%,while the%ID of Au remained nearly unchanged.We proved the gradual dissociation of AgNPs into Ag ions using a fluorescent probe.Therefore,density-dependent dynamics of NPs in the blood caused greater liver accumulation of low-density Ag.However,the gradual degradation of AgNPs contributes to a high degree of distribution of Ag in the body while the AuNPs remain sequestered in the liver.This study implies that the dynamic transformation of NPs complicates their density-dependent retention,which are plausible to determine the accumulation and biological effects to the organisms. 展开更多
关键词 metal nanoparticles Stability DENSITY DISSOLUTION CO-EXPOSURE Fluorescent probe
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Exotic superconductivity in new topological kagome metal CsTi_(3)Bi_(5)
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作者 Jiali Liu Zhen Zhao +11 位作者 Hongqin Xiao Yuhang Zhang Zouyouwei Lu Jihu Lu Feng Wu Chengjie Xu Hua Zhang Hui Chen Haitao Yang Ziyi Liu Xiaoli Dong Hongjun Gao 《Chinese Physics B》 2026年第2期264-270,共7页
We present a systematic investigation of the superconductivity in high-quality CsTi_(3)Bi_(5) single crystals by combining bulk property characterization and local-probe spectroscopy.Two successive superconducting tra... We present a systematic investigation of the superconductivity in high-quality CsTi_(3)Bi_(5) single crystals by combining bulk property characterization and local-probe spectroscopy.Two successive superconducting transitions are observed in this newly discovered kagome material.In the first stage,the diamagnetic response strengthens significantly from T_(c)~4.9 K to 4.6 K,followed by a broad transition below 4.6 K in the second stage.Moreover,different magnetic field dependences are observed for the two stages,where the first stage is field-insensitive while the second stage exhibits strong field dependence.The ultra-low magnetic field measurements indicate that the lower critical field H_(c1)(T)exhibits small anisotropy.Based on a comparative study of the superconducting state in CsBi2 and microscopic verification via scanning tunneling microscopy(STM),our results suggest the emergence of exotic and intrinsic superconductivity in this new titanium-based kagome superconductor,establishing it as a promising platform for further exploring the complexity of electronic states in the kagome lattice. 展开更多
关键词 kagome metal titanium-based material SUPERCONDUCTIVITY critical field
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Transition metal-catalyzed C-H activation/annulation for the construction of unnatural amino acids and peptides
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作者 Xiao Tang Erik V.Van der Eycken Liangliang Song 《Chinese Chemical Letters》 2026年第2期191-205,共15页
Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face wit... Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face with their intrinsic limitations including metabolic instability and low membrane permeability,the strategies for synthesizing unnatural amino acids and peptides are explored.Among the methods for modifying amino acids and peptides,chemo-and site-selective approaches are preferred because of the ability to fine-tuning structural features.Recently,transition metal-catalyzed C–H activation has been employed for the functionalization of amino acids and peptides.Through domino C–H activation/annulation,a series of structurally complex and diverse amino acids and peptides is constructed.This review highlights recent advances in the synthesis of unnatural amino acids and peptides via transition metal-catalyzed C–H activation/annulation. 展开更多
关键词 Amino acid PEPTIDE Transition metal C-H activation ANNULATION
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