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Osteogenic and antibacterial ability of micro-nano structures coated with ZnO on Ti-6Al-4V implant fabricated by two-step laser processing 被引量:4
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作者 Yi Wan Zihe Zhao +5 位作者 Mingzhi Yu Zhenbing Ji Teng Wang Yukui Cai Chao Liu Zhanqiang Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第36期240-252,共13页
The biological performance of Ti-6Al-4V implant is primarily determined by their surface properties.However,traditional surface modification methods,such as acid etching,hardly make improvement in their osseointegrati... The biological performance of Ti-6Al-4V implant is primarily determined by their surface properties.However,traditional surface modification methods,such as acid etching,hardly make improvement in their osseointegration ability and antibacterial capacity.In this study,we prepared a multi-scale composite structure coated with zinc oxide(ZnO)on Ti-6Al-4V implant by an innovative technology of two-step laser processing combined with solution-assistant.Compared with the acid etching method,the physicochemical properties of surface significantly improved.The in vitro results showed that the particular dimension of micro-nano structure and the multifaceted nature of ZnO synergistically affected MC3T3-E1 osteogenesis and bacterial activities:(1)The surface morphology showed a‘contact guidance'effect on cell arrangement,which was conducive to the adhesion of filopodia and cell spreading,and the osteogenesis level of MC3T3-E1 was enhanced due to the release of zinc ions(Zn^(2+));(2)the characterization of bacterial response revealed that periodic nanostructures and Zn^(2+)released could cause damage to the cell wall of E.coli and reduce the adhesion and aggregation of S.aureus.In conclusion,the modified surface showed a synergistic effect of physical topography and chemical composition,making this a promising method and providing new insight into bone defect repairment. 展开更多
关键词 Ti-6Al-4V implant Laser processing micro-nano structure Zinc oxide Osseointegration ability Antibacterial capacity
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Micro-nano structured VNb_(9)O_(25)anode with superior electronic conductivity for high-rate and long-life lithium storage 被引量:2
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作者 Mingxing Liang Yongcong Huang +7 位作者 Yuda Lin Guisheng Liang Cihui Huang Lan Chen Jiaxin Li Qian Feng Chunfu Lin Zhigao Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第24期66-74,共9页
The oxygen vacancies and micro-nano structure can optimize the electron/Li+migration kinetics in anode materials for lithium batteries(LIBs).Here,porous micro-nano structured VNb_(9)O_(25)composites with rich oxygen v... The oxygen vacancies and micro-nano structure can optimize the electron/Li+migration kinetics in anode materials for lithium batteries(LIBs).Here,porous micro-nano structured VNb_(9)O_(25)composites with rich oxygen vacancies were reasonably prepared via a facile solvothermal method combined with annealing treatment at 800℃for 30 h(VNb_(9)O_(25)-30 h).This micro-nano structure can enhance the contact of active material/electrolyte,and shorten the Li+diffusion distance.The introduction of oxygen vacancies can further boosts the intrinsic conductivity of VNb_(9)O_(25)-30 h for achieving excellent LIB performance.The as-prepared VNb_(9)O_(25)-30 h anode showed advanced rate capability with reversible capacity of 122.2 m A h g^(-1)at 4 A g^(-1),and delivered excellent capacity retention of~100%after 2000 cycles.Meanwhile,VNb_(9)O_(25)-30 h provides unexpected long-cycle life(i.e.,reversible capacity of 165.7 m A h g^(-1)at 1 A g^(-1)with a high capacity retention of 85.6%even after 8000 cycles).Additionally,coupled with the Li Fe PO4 cathode,the Li Fe PO4//VNb_(9)O_(25)-30 h full cell delivers superior LIB properties with high reversible capacities of 91.6 m A h g^(-1)at 5 C for 1000 cycles.Thus,such reasonable construction method can assist in other high-performance niobium-based oxides in LIBs. 展开更多
关键词 Lithium-ion batteries VNb_(9)O_(25)anode micro-nano structure Oxygen vacancies Electrochemical performance
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Investigation on Surface Plasmon Polaritons and Localized Surface Plasmon Production Mechanism in Micro-Nano Structures 被引量:1
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作者 Ling-Xi Hu Min Hu Sheng-Gang Liu 《Journal of Electronic Science and Technology》 CAS CSCD 2022年第1期20-29,共10页
The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons gr... The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons grating(Au substrate grating),and pure electric conductor(PEC)substrate with Au ribbons grating(Au ribbons grating).And the characteristics of the Smith-Purcell radiation in these structures were presented.Simulation results show that SPPs are excited on the bottom surface of Au substrate grating grooves and LSP is stimulated on the upper surface both of Au ribbons grating grooves and Au grating grooves.Owing to the irreconcilable contradiction between optimizing the grating diffraction radiation efficiency and optimizing the SPPs excitation efficiency in the Au substrate grating,only 40-times enhancement of the radiation intensity was obtained by excited SPPs.However,the LSP enhanced structure overcomes the above problem and gains much better radiation enhancement ability,with about 200-times enhancement obtained in the Au ribbons grating and more than 500-times enhancement obtained in the Au grating.The results presented here provide a way of developing miniature,integratable,tunable,high-power-density radiation sources from visible light to ultraviolet rays at room temperature. 展开更多
关键词 Coherent radiation high-power radiation localized surface plasmon(LSP) micro-nano structure Smith-Purcell radiation surface plasmon polaritons(SPPs)
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Synthesis and electrochemical performance of micro-nano structured Li Fe1-xMnxPO4/C(0≤x≤0.05)cathode for lithium-ion batteries 被引量:1
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作者 Chunyang Li Guojun Li Xiaomei Guan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第3期923-929,共7页
Micro-nano structured Li Fe(1-x)MnxPO4/C(0≤x≤0.05)cathodes were prepared by spray drying,followed by calcination at 700°C.The spherical Li Fe(1-x)MnxPO4/C(0≤x≤0.05)particles with the size of 0.5 to5.0... Micro-nano structured Li Fe(1-x)MnxPO4/C(0≤x≤0.05)cathodes were prepared by spray drying,followed by calcination at 700°C.The spherical Li Fe(1-x)MnxPO4/C(0≤x≤0.05)particles with the size of 0.5 to5.0μm are composed of lots of nanoparticles of 20 to 30 nm,and have the well-developed interconnected pore structure.In contrast,when Mn doping content is 3 mol%(x=0.03),the Li Fe(0.97)Mn(0.03)PO4/C demonstrates maximum specific surface area of 31.30 m^2/g,more uniform pore size and relatively better electrochemical performance.The initial discharge capacities are 161.59,157.04 and 153.13 m Ah/g at a discharge rate of 0.2,0.5 and 1 C,respectively.Meanwhile,the discharge capacity retentions are~100%after 120 cycles.The improved electrochemical performance should be attributed to higher specific surface,smaller polarization voltage,and a high Li~+diffusion rate due to the micro-nano porous structure and lattice expansion produced by Mn doping. 展开更多
关键词 Li Fe1-xMnxPO4/C Spray drying Electrochemical property micro-nano structure
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Recent progress on fabrication, spectroscopy properties, and device applications in Sn-doped CdS micro-nano structures
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作者 Bo Cao Ye Tian +8 位作者 Huan Fei Wen Hao Guo Xiaoyu Wu Liangjie Li Zhenrong Zhang Lai Liu Qiang Zhu Jun Tang Jun Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期7-27,共21页
One-dimensional semiconductor materials possess excellent photoelectric properties and potential for the construction of integrated nanodevices. Among them, Sn-doped CdS has different micro-nano structures, including ... One-dimensional semiconductor materials possess excellent photoelectric properties and potential for the construction of integrated nanodevices. Among them, Sn-doped CdS has different micro-nano structures, including nanoribbons,nanowires, comb-like structures, and superlattices, with rich optical microcavity modes, excellent optical properties, and a wide range of application fields. This article reviews the research progress of various micrometer structures of Sn-doped CdS, systematically elaborates the effects of different growth conditions on the preparation of Sn-doped CdS micro-nano structures, as well as the spectral characteristics of these structures and their potential applications in certain fields. With the continuous progress of nanotechnology, it is expected that Sn-doped CdS micro-nano structures will achieve more breakthroughs in the field of optoelectronics and form cross-integration with other fields, jointly promoting scientific, technological, and social development. 展开更多
关键词 Sn-doped CdS micro-nano structure SUPERLATTICES optical microcavity
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Potential application of functional micro-nano structures in petroleum
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作者 LIU He JIN Xu +2 位作者 ZHOU Dekai YANG Qinghai LI Longqiu 《Petroleum Exploration and Development》 2018年第4期745-753,共9页
This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure d... This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure design and manufacturing technology in the petroleum industry. The functional micro-nano structure is the structure and device with special functions prepared to achieve a specific goal. New functional micro-nano structures are classified into mobile type(e.g. micro-nano motors) and fixed type(e.g. metamaterials), and 3 D printing technology is a developed method of manufacturing. Combining the demand for exploration and development in oil and gas fields and the research status of intelligent micro-nano structures, we believe that there are 3 potential application directions:(1) The intelligent micro-nano structures represented by metamaterials and smart coatings can be applied to the oil recovery engineering technology and equipment to improve the stability and reliability of petroleum equipment.(2) The smart micro-nano robots represented by micro-motors and smart microspheres can be applied to the development of new materials for enhanced oil recovery, effectively improving the development efficiency of heavy oil, shale oil and other resources.(3) The intelligent structure manufacturing technology represented by 3 D printing technology can be applied to the field of microfluidics in reservoir fluids to guide the selection of mine flooding agents and improve the efficiency of mining. 展开更多
关键词 PETROLEUM industry micro-nano structures micro-nano motor METAMATERIALS 3D PRINTING application direction OIL production engineering OIL equipment enhanced OIL recovery
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Mechanical Simulation of Hierarchical Micro-Nano Structure of Butterfly Wings
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作者 SHI Shunjie GE Dengteng +2 位作者 JIN Junhong LI Guang YANG Shenglin 《Journal of Donghua University(English Edition)》 EI CAS 2020年第1期10-16,共7页
The ridge-cross rib microstructures of Carystoides escalantei butterfly wing scales have been reproduced by 2D and 3D models via the ANSYS software,and the structural analyses under tensile and bending deformation,as ... The ridge-cross rib microstructures of Carystoides escalantei butterfly wing scales have been reproduced by 2D and 3D models via the ANSYS software,and the structural analyses under tensile and bending deformation,as well as the relative failure analyses are performed for those models.It has been found that the curved model in which the ridges acted as triangular prisms while the cross-ribs acted as bend cuboids could simulate the real scale configuration more accurately.Besides,it also shows much more even stress distribution under deformation and better mechanical properties than the rectangular one,in which both ridges and cross-ribs are modeled as regular cuboids. 展开更多
关键词 BUTTERFLY scales MULTILEVEL structure BIONIC model MECHANICAL simulation
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
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作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
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A novel Angle-Constrained Optimization method of Conformal Lattice Structures
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作者 Jun Yan Weibin Xu +2 位作者 Fuhao Wang Sixu Huo Kun Yan 《Computer Modeling in Engineering & Sciences》 2026年第2期269-295,共27页
Conformal truss-like lattice structures face significant manufacturability challenges in additive manufac-turing due to overhang angle limitations.To address this problem,we propose a novel angle-constrained optimizat... Conformal truss-like lattice structures face significant manufacturability challenges in additive manufac-turing due to overhang angle limitations.To address this problem,we propose a novel angle-constrained optimization method grounded in the global adjustment of nodal coordinates.First,a build direction is selected to minimize the number of violating struts.Then,an angular-constraint matrix is assembled from strut direction vectors,and analytical sensitivities with respect to nodal coordinates are derived to enable efficient constrained optimization under nonlinear angular inequality constraints.Numerical studies on two complex curved-surface lattices demonstrate that all overhang violations are eliminated while only minor changes are induced in global stiffness and strength.In particular,the maximum displacement of an ergonomic insole varies by only 2.87%after optimization.The results confirm the method’s versatility and engineering robustness,providing a practical approach for additive manufacturing-oriented lattice structure design. 展开更多
关键词 Conformal lattice structures additive manufacturing structural optimization complex structures
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Multi-objective topology optimization for cutout design in deployable composite thin-walled structures
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作者 Hao JIN Ning AN +3 位作者 Qilong JIA Chun SHAO Xiaofei MA Jinxiong ZHOU 《Chinese Journal of Aeronautics》 2026年第1期674-694,共21页
Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structu... Deployable Composite Thin-Walled Structures(DCTWS)are widely used in space applications due to their ability to compactly fold and self-deploy in orbit,enabled by cutouts.Cutout design is crucial for balancing structural rigidity and flexibility,ensuring material integrity during large deformations,and providing adequate load-bearing capacity and stability once deployed.Most research has focused on optimizing cutout size and shape,while topology optimization offers a broader design space.However,the anisotropic properties of woven composite laminates,complex failure criteria,and multi-performance optimization needs have limited the exploration of topology optimization in this field.This work derives the sensitivities of bending stiffness,critical buckling load,and the failure index of woven composite materials with respect to element density,and formulates both single-objective and multi-objective topology optimization models using a linear weighted aggregation approach.The developed method was integrated with the commercial finite element software ABAQUS via a Python script,allowing efficient application to cutout design in various DCTWS configurations to maximize bending stiffness and critical buckling load under material failure constraints.Optimization of a classical tubular hinge resulted in improvements of 107.7%in bending stiffness and 420.5%in critical buckling load compared to level-set topology optimization results reported in the literature,validating the effectiveness of the approach.To facilitate future research and encourage the broader adoption of topology optimization techniques in DCTWS design,the source code for this work is made publicly available via a Git Hub link:https://github.com/jinhao-ok1/Topo-for-DCTWS.git. 展开更多
关键词 Composite laminates Deployable structures Multi-objective optimization Thin-walled structures Topology optimization
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Energy absorption behavior of mild steel tube-core sandwich structures for rockfall protection
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作者 HUANG Fuyou ZHANG Luqing +3 位作者 ZHOU Jian HAN Zhenhua WANG Song SUN Qihao 《Journal of Mountain Science》 2026年第1期171-187,共17页
Sandwich structures are widely favored for their lightweight,high strength and superior impact mitigation capabilities in blast mitigation and transportation safety applications.Their application in large-scale,high-e... Sandwich structures are widely favored for their lightweight,high strength and superior impact mitigation capabilities in blast mitigation and transportation safety applications.Their application in large-scale,high-energy rockfall protection remains limited due to their relatively low volumetric energy absorption efficiency and the complex fabrication processes of key energy-absorbing components.To address these limitations,this study proposes a novel sandwich structure incorporating mild steel tubes as core energy absorbers to efficiently mitigate highenergy rockfall impacts.A finite element model was developed in LS-DYNA to systematically investigate the deformation and energy absorption behaviors.Comprehensive parametric analyses were conducted to quantify the effects of key design variables,including tube wall thickness,tube spacing(number of tubes),and infill materials.The results demonstrate that increasing tube wall thickness significantly enhances ultimate energy absorption,with 12-mm-thick tubes absorbing 2.2 times more energy than 6-mm-thick tubes.Lateral constraints induced by adjacent tubes improve specific energy absorption per unit displacement by approximately 30%-45%.Furthermore,incorporating infill materials considerably enhances energy absorption,with aluminum foam infills achieving an 81%increase compared to empty tubes.Nevertheless,higher energy absorption capacity typically leads to greater peak impact forces,increasing the number of tubes offers a better balance between energy absorption and impact force,optimizing the structural performance.These findings provide valuable theoretical insights and practical guidelines for designing sandwich structures in civil and infrastructure engineering applications for effective rockfall protection. 展开更多
关键词 Sandwich structure Mild steel tube Rockfall impact Energy absorption structural optimization
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Energy absorption characteristics of additively manufactured sea sponge-inspired lattice structures under low-velocity impact loading
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作者 J Jefferson Andrew Jabir Ubaid +4 位作者 Mohammed Ayaz Uddin Omar Waqas Saadi Kamran Ahmed Khan Rehan Umer Andreas Schiffer 《Defence Technology(防务技术)》 2026年第1期118-129,共12页
Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-ins... Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-inspired lattice structures feature a square-grid 2D lattice with double diagonal bracings and are additively manufactured via digital light processing(DLP).The collapse strength and energy absorption capacity of sea sponge lattice structures are evaluated under various impact conditions and are compared to those of their constituent square-grid and double diagonal lattices.This study demonstrates that sea sponge lattices can achieve an 11-fold increase in energy absorption compared to the square-grid lattice,due to the stabilizing effect of the double diagonal bracings prompting the structure to collapse layer-bylayer under impact.By adjusting the thickness ratio in the sea sponge lattice,up to 76.7%increment in energy absorption is attained.It is also shown that sea-sponge lattices outperform well-established energy-absorbing materials of equal weight,such as hexagonal honeycombs,confirming their significant potential for impact mitigation.Additionally,this research highlights the enhancements in energy absorption achieved by adding a small amount(0.015 phr)of Multi-Walled Carbon Nanotubes(MWCNTs)to the photocurable resin,thus unlocking new possibilities for the design of innovative lightweight structures with multifunctional attributes. 展开更多
关键词 Sea sponge-inspired lattice structures Additive manufacturing Energy absorption Low-velocity impact Lattice structure NANOCOMPOSITE
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/AC catalyst NH_(3)-SCR performance
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Development of the vertebral column and fin support structures in Encrasicholina punctifer larvae and juveniles
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作者 PASSMORE Roland Madziva WANG Xiaodong +1 位作者 DU Zhipeng ZHONG Junsheng 《水产学报》 北大核心 2026年第2期145-158,共14页
Anchovies are key forage species in coastal and pelagic food webs,playing crucial ecological and commercial roles in marine ecosystems.Encrasicholina punctifer is a commercially and ecologically important species,yet ... Anchovies are key forage species in coastal and pelagic food webs,playing crucial ecological and commercial roles in marine ecosystems.Encrasicholina punctifer is a commercially and ecologically important species,yet little is known about its osteological development characteristics.Understanding these ontogenetic patterns is essential for explaining phylogenetic relationships within Clupeiformes,informing larval identification in ichthyoplankton surveys,and enhancing aquaculture practices.This study describes the ontogenetic characteristics of the appendicular and median skeletons and fin supports in E.punctifer larvae and juveniles,providing quantitative ontogenetic timelines to address gaps in engraulid developmental biology and contribute to teleost ontogeny research.Larval and juvenile specimens of E.punctifer;size range:3.00-34.56 mm standard length(SL)and notochord length(NL)collected from the Philippine Sea were processed using the standard Alizarin red and Alcian blue clearing-and-staining technique to differentiate ossified and cartilaginous elements.Specimens were examined under a stereo microscope and imaged with an HTC1600ISP digital camera for detailed morphological analysis of skeletal structures.Caudal complex development was evident by 5.55 mm NL,with the initial appearance of cartilaginous hypurals 1–2 and parhypural,followed by Hy3–5 at 6.08 mm NL.Cartilaginous Hy6 was visible by 9.58 mm SL in postflexion larvae.Six hypural bones were present from the postflexion to juvenile stage.Principal fin rays formed via intramembranous ossification at 6.32 mm NL,and segmentation was evident by 10.24 mm SL.Neural arch 1 appeared at 7.38 mm NL,preceding full haemal arch development.Uroneurals 1–2 and ural centra ossified by 9.58 mm SL,with Hy5 detached from U1 at 10.24 mm SL.Preural centra ossified before the arches.Epurals 1 and 2 were evident by 10.24 mm SL.Dorsal fin proximal radials developed anteriorly and distal radials posteriorly.Pectoral fin development initiated with an ossified cleithrum and the coracoscapular cartilage at 5.25 mm NL.By 10.24 mm SL,cartilaginous neural and haemal arches and spines were distinct.Uroneural 1 initially develops as cartilage.The formation of a pleurostyle aligns with clupeoid fish skeletal ontogeny.Dorsal and anal fin development follows a distinctive pattern,with variability in fin support development.Our results reveal accelerated caudal complex formation in E.punctifer and contribute new knowledge on the osteological characteristics of the genus Encrasicholina,and aid in understanding larval and juvenile ontogeny of marine teleosts. 展开更多
关键词 Encrasicholina punctifer skeletal structures ONTOGENY larvae and juveniles staining and clearing of cartilage and bone
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Enhanced Flow Boiling Heat Transfer of HFE-7100 in Open Microchannels Using Micro-Nano Composite Structures
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作者 Liaofei Yin Kexin Zhang +3 位作者 Tianjun Qin Wenhao Ma YiDing Yawei Xu 《Frontiers in Heat and Mass Transfer》 2025年第3期751-764,共14页
Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermalmanagement of electronic devices in recent years.Ho... Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermalmanagement of electronic devices in recent years.However,the continuous rise in power density of electronic components imposesmore stringent requirements on the heat transfer capability of microchannel flow boiling.HFE-7100,a dielectric coolant with favorable thermophysical properties,has become a focal point of research for enhancing flow boiling performance in open microchannels.The flow boiling heat transfer performance ofHFE-7100 was investigated in this study by fabricating micro-nano composite structures on the bottom surface of open microchannels using laser ablation technology.Based on visualization results,a comparative analysis was conducted on the bubble dynamics and flow pattern characteristics of HFE-7100 flow boiling in micronano structured open microchannels(MNSOMC)and smooth-surface open microchannels(SSOMC),to elucidate the enhancement mechanism of micro-nano structures on flow boiling heat transfer in open microchannels.The results indicate that the surface structures and strong wettability of MNSOMC accelerated bubble nucleation and departure.Moreover,bubbles in the channel tended to coalesce along the flow direction,forming elongated slug bubbles with high aspect ratios,which enabled efficient thin film evaporation in conjunction with intense nucleate boiling,thereby significantly enhancing flow boiling heat transfer.Under the experimental conditions of this study,the maximum enhancements in the heat transfer coefficient(HTC)and critical heat flux(CHF)of HFE-7100 inMNSOMC were 33.4%and 133.1%,respectively,with the CHF reaching up to 1542.3 kW⋅m^(−2).Furthermore,due to the superior wettability and capillary wicking capability of the micro-nano composite structures,the significant enhancement in flow boiling heat transfer was achieved without incurring a noticeable pressure drop penalty. 展开更多
关键词 Open microchannel laser ablation micro-nano composite structures flow boiling heat transfer enhancement
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Synthesis and crystal structures of Co(Ⅱ)/Cu(Ⅱ)coordination polymers based on solvent and ligand concentration regulation strategy
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作者 SUN Yinxia LIU Liping +7 位作者 BAI Xue SUN Yu SUN Wanhong DENG Zhepeng CHEN Jianghai WANG Jianjun XU Li ZHANG Shuzhen 《无机化学学报》 北大核心 2026年第2期340-354,共15页
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2... Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4. 展开更多
关键词 Co(Ⅱ)/Cu(Ⅱ)coordination polymer crystal structure solvent system ligand concentration regulation strategy
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Association of tertiary lymphoid structures and benign lymphoepithelial lesions in NIH-category IV prostatitis:pathophysiological correlations
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作者 Dorian Dikov Maria Koleva +3 位作者 Kiril Simitchiev Anelia Bivolarska Albena Fakirova Victoria Sarafian 《The Canadian Journal of Urology》 2026年第1期125-134,共10页
Background:Chronic inflammation is closely associated with the most common and socially significant prostate conditions,including benign prostatic hyperplasia(BPH),prostate cancer(PCa),and prostatitis syndromes.NIHcat... Background:Chronic inflammation is closely associated with the most common and socially significant prostate conditions,including benign prostatic hyperplasia(BPH),prostate cancer(PCa),and prostatitis syndromes.NIHcategory IV prostatitis(histologic prostatitis,HP)is defined as asymptomatic chronic inflammation of the prostate.The presence of lymphoid follicles,referred to as tertiary lymphoid structures(TLSs),along with benign lympho-epithelial lesions(BLELs),is among the key histological indicators of immune inflammation and can be assessed relatively easily.This study aimed to quantitatively assess TLSs and BLELs,as well as their relationship with the severity of HP.Methods:We investigated TLSs and BLELs in 110 prostatic specimens,including inflammatory and normal tissues,within the context of common prostate pathologies such as BPH and PCa.HP was graded as low-grade(LG)or high-grade(HG)based on the severity of inflammation.Results:TLSs were observed in 51 out of 110 cases(46.4%),while BLELs were identified in 78 cases(70.44%).Both TLSs and BLELs co-occurred in 45 cases(40.9%).Statistical analysis revealed a significant correlation between the presence of TLSs,BLELs(individually or combined),and HG-HP(p<0.001).Conclusions:This study is the first to quantitatively evaluate the immunopathologic patterns in the inflamed human prostate by analyzing the presence and cooccurrence of TLSs and BLELs.Their formation,likely triggered by antigenic stimuli and external factors,indicates a chronic inflammatory microenvironment.The strong association between TLSs,BLELs,and HG-HP underscores their potential role in HP aggressiveness.These findings suggest that TLSs and BLELs may be crucial contributors to the pathophysiology and morphogenesis of NIH-category IV prostatitis.Furthermore,TLS/BLEL formation may represent a hallmark of tissue autoimmunity,reflecting the immune or autoimmune phase of this prostatitis subtype. 展开更多
关键词 PROSTATITIS tertiary lymphoid structures lymphoepithelial lesion
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A novel scaling method for the elastic ring supporting structure of an aero-engine rotor system: analytical and experimental investigations
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作者 Lei LI Tianyue MA +4 位作者 Zhong LUO Dongwu GAO Xiangdong GE Hui MA Shibin WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期1-18,共18页
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr... The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings. 展开更多
关键词 rotor system AERO-ENGINE elastic ring scaling method supporting structure
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Determining the Effect of Grain Size on the Microstructure and Oxidation of Nuclear Graphite
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作者 Xu Qiao Xinlei Cao +6 位作者 Yuying Zhang Wei Chen Chunzhen Yang Zhengcao Li Xing Zhou Ke Shen Zhou Zhou 《Carbon Energy》 2026年第1期138-152,共15页
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,... Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors. 展开更多
关键词 DIFFUSION nuclear graphite OXIDATION pore structure reaction rate
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