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IMPROVINg THE SURFACE PROPERTy OF TC4 ALLOy By LASER NITRIDINg AND ITS MECHANISM

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 151-156页

作者： y.L. yang g.J. Zhao D. zhang C.S. Liu gollege of Sdence Northeastern University Shenyang 110004 Ghina College of Material and Metallurgy Northeastern University Shenya g 110004 China

The mixing technology of laser and heated nitrogen was applied to improve the surface hardness of titanium alloy （ TC4 ）. The samples were nitrided with laser power density of 6.S × 10^6SW. cm^-2, the scanning speed varioas from 100 to 500mm ·min^-1. The nitrogen gas was pre-heated to 300℃ to accelerate the nitriding process. Some interested samples were tested with XRD method （X-ray diffraction） to analyze the composition of nitrides, and the surface hardness of HV was measured. The results show that TiN and Ti2N were formed on the surface of Ti alloy with proper nitriding parameters, but TiN is the main composition. The surface hardness increased by three times, which is from the original value of 269to 794kg·mm^-2. The mechanism of the mixing technology is considered mainly of the activation of nitrogen by laser power and the pre-heated process which accelerated the nitriding process. The nitridation process can be considered as six steps given in detail. The result by analyzing the mechanism of improving the surface property of TiAl alloy shows the improvement of surface property due to two factors： the first reason is the result of laser annealing, and the second one is the formation of TiN.

关键词： laser nitridation surface property Ti alloy

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： genfu Zhao Hang Ma Conghui zhang yongxin yang Shuyuan yu Haiye Zhu yongjiang Sun Hong guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China yunnan yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

Thermal Properties of PHB/PEg Blends

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Journal of Materials Science & Technology 1998年第1期14卷 95-96页

作者： zhang, QQ zhang, y Wang, FJ Liu, LR Wang, C Chinese Acad Med Sci Inst Biomat Engn Tianjin 300192 Peoples R China Peking Union Med Coll Tianjin 300192 Peoples R China Univ Utah Salt Lake City UT 84112 USA

Thermal properties of PHB and PHB/PEg blends were investigated by differential scanning calorimetry (DSC) and melt index (MI) test. DSC thermograms indicate that two components of blend are miscible. From the DSC thermogram, we can also conclude that the melting point of PHB descends with the increased content of PEg, this can improve PHB processing properties. From MI data, we may draw the same conclusion.

关键词： Polyesters

Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film growth Dynamics

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Nano-Micro Letters 2025年第2期17卷 387-400页

作者： Mengen Ma Cuiling zhang yujiao Ma Weile Li yao Wang Shaohang Wu Chong Liu yaohua Mai Institute of New Energy Technology College of Physics&Optoelectronic EngineeringJinan UniversityGuangzhou 510632People’s Republic of China Key Laboratory of New Semiconductors and Devices of guangdong Higher Education Institutes Jinan UniversityGuangzhou 510632People’s Republic of China guangdong Mellow Energy Co. LimitedYuanming RoadZhuhai 519075GuangdongPeople’s Republic of China

gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating *** this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive *** then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air.

关键词： gas quenching Additive distribution Buried passivation Blade coating Crystallization dynamics

High Fe‑Loading Single‑Atom Catalyst Boosts ROS Production by Density Effect for Efficient Antibacterial Therapy

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Nano-Micro Letters 2025年第2期17卷 187-203页

作者： Si Chen Fang Huang Lijie Mao Zhimin zhang Han Lin Qixin yan Xiangyu Lu Jianlin Shi Department of Cardiology Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200092People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China Shanghai Frontiers Science Center of Nanocatalytic Medicine School of MedicineTongji UniversityShanghai 200092People’s Republic of China

The current single-atom catalysts(SACs)for medicine still suffer from the limited active site ***,we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with *** constructed iron SACs(h^(3)-FNC)with a high metal loading of 6.27 wt%and an optimized adjacent Fe distance of~4 A exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial ***,a“density effect”has been found at a high-enough metal doping amount,at which individual active sites become close enough to interact with each other and alter the electronic structure,resulting in significantly boosted intrinsic activity of single-atomic iron sites in h^(3)-FNCs by 2.3 times compared to low-and medium-loading ***,the overall catalytic activity of h^(3)-FNC is highly improved,with mass activity and metal mass-specific activity that are,respectively,66 and 315 times higher than those of commercial Pt/*** addition,h^(3)-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion(O_(2)·^(−))and glutathione(gSH)*** in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h^(3)-FNCs in promoting wound *** work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections.

关键词： Nanocatalytic medicine Single-atom catalysts Reactive oxygen species(ROS) High metal loading Oxidase catalysis

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： yubo Wang Tingli yuan Tianjie Lyu Ling zhang Meng Wang Zhiying He yongjun Wang Zixiao Li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational Medicine ShanghaiChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell

Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber

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Nano-Micro Letters 2025年第1期17卷 424-438页

作者： Honghan Wang Xinyu Xiao Shangru Zhai Chuang Xue guangping Zheng Deqing zhang Renchao Che Junye Cheng Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034People’s Republic of China School of Life Science and Biotechnology Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen 517182People’s Republic of China

The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric *** migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent ***,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent *** virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 *** mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).

关键词： High-entropy alloys Carbothermal shock Switchable electron migration modes Emblematic shell-core heterointerfaces Ultra-thin thickness

Enhancement of shear stability of a Fe-based amorphous alloy using electrodeposited Ni layers

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Journal of Materials Science & Technology 2018年第12期34卷 2283-2289页

作者： y.C.Wang X.M.Luo L.J.Chen H.W.yang B.zhang g.P.zhang School of Materials Science and Engineering Shenyang University of Technology Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationSchool of Materials Science and EngineeringNortheastern University

Tensile and fracture behaviors of sandwich-structured composites consisting of a Fe-based amorphous layer with a constant thickness and ultrafine-grained Ni layers with different thicknesses were investigated. The results indicate that the initiation and the stable propagation of the shear band in the amorphous layer was dominated by the Ni layers due to their strong constraint role. The catastrophic fracture of the amorphous layer was postponed in the sandwich composites through properly increasing the constrained Ni layer thickness, which effectively decreased the shear stress on the shear fracture planes of the amorphous layer, and thus led to stable propagation of the primary SB characterized by the increase in the smooth region size of the shear band.

关键词： Sandwich-structured composites Amorphous alloy Shear stability Plasticity Fracture

Study on the hydrogen absorption properties of a ygdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen yang Anjia zhang yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the ygdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the ygdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics