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Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang Guo Di lan Zirui Jia Zhenguo gao Xuetao Shi Mukun He Hua Guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min Xing Hai-Dong Qian Qiao gao Sheng-lan Xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

Preparation and photo-catalytic activity of TiO_2-coated medical stone-based porous ceramics

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 593-597页

作者： ru-qin gao Xin-mei hou School of Environmental and Municipal Engineering North China University of Water Resources and Electric Power School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Medical stone-based porous ceramics as a carrier were prepared by ultra-fine grinding and low-temperature sintering method. Nano-TiO~ thin films were loaded on the carrier by chemical liquid deposition method using titanium tetrachloride as a precursor. The micro-morphology and microstructure of the synthesized samples were characterized using X-ray diffraction, scanning electron microscopy with energy dispersive spectrometry, and mercury injection method. The photo-catalytic activity of the TiO2 thin films was investigated by degrading formaldehyde. The main crystalline phase in the TiO2 thin films calcined at 550~C is anatase with the average particle size about 10 nm. The specific surface area of the carrier-coated nano-TiO2 increases from 3.68 to 5.32 m2/g. The formaldehyde removal rate of the TiO2/medical stone-based porous ceramics irradiated under an ultraviolet lamp for 120 min reaches 85.6%.

关键词： porous materials ceramics medical stone titanium dioxide thin films formaldehyde photocatalysis

A hybrid vertex-centered finite volume/element method for viscous incompressible flows on non-staggered unstructured meshes

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Acta Mechanica Sinica 2012年第2期28卷 324-334页

作者： Wei gao ru-Xun Liu hong Li School of Mathematical Sciences Inner Mongolia University010021 HuhhotChina Department of Mathematics University of Science and Technology of China230026 HefeiChina

This paper proposes a hybrid vertex-centered fi- nite volume/finite element method for solution of the two di- mensional （2D） incompressible Navier-Stokes equations on unstructured grids. An incremental pressure fractional step method is adopted to handle the velocity-pressure coupling. The velocity and the pressure are collocated at the node of the vertex-centered control volume which is formed by join- ing the centroid of cells sharing the common vertex. For the temporal integration of the momentum equations, an im- plicit second-order scheme is utilized to enhance the com- putational stability and eliminate the time step limit due to the diffusion term. The momentum equations are discretized by the vertex-centered finite volume method （FVM） and the pressure Poisson equation is solved by the Galerkin finite el- ement method （FEM）. The momentum interpolation is used to damp out the spurious pressure wiggles. The test case with analytical solutions demonstrates second-order accuracy of the current hybrid scheme in time and space for both veloc- ity and pressure. The classic test cases, the lid-driven cavity flow, the skew cavity flow and the backward-facing step flow, show that numerical results are in good agreement with the published benchmark solutions.

关键词： Incompressible flow Vertex-centered finite vol- ume method Finite element method - Unstructured grid

Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： Hao LU lan gao Yunda yaN Mingzhe hou Chenliang WANG Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight *** cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the *** the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal ***,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector ***-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

THE FINITE VOLUME PROJECTION METHOD WITH HYBRID UNSTruCTURED TRIANGULAR COLLOCATED GRIDS FOR INCOMPRESSIBLE FLOWS

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Journal of Hydrodynamics 2009年第2期21卷 201-211页

作者： gao Wei DUAN ya-li LIU ru-xun Department of Mathematics University of Science and Technology of China Hefei 230026 China

In this article a finite volume method is proposed to solve viscous incompressible Navier-Stokes equations in two-dimensional regions with corners and curved boundaries. A hybrid collocated-grid variable arrangement is adopted, in which the velocity and pressure are stored at the centroid and the circumcenters of the triangular control cell, respectively. The cell flux is defined at the mid-point of the cell face. Second-order implicit time integration schemes are used for convection and diffusion terms. The second-order upwind scheme is used for convection fluxes. The present method is validated by results of several viscous flows.

关键词： incompressible viscous flows Navier-Stokes equations finite volume method projection method unstructured collocated grid

NUMERICAL INVESTIGATION ON NON-NEWTONIAN FLOWS THROUGH DOUBLE CONSTRICTIONS BY AN UNSTruCTURED FINITE VOLUME METHOD

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Journal of Hydrodynamics 2009年第5期21卷 622-632页

作者： gao Wei LIU ru-xun DUAN ya-li Department of Mathematics University of Science and Technology of China Hefei 230026 China

This article presents a numerical investigation on a steady non-Newtonian flow through a two-dimensional channel with double constrictions. The power-law mode is employed in describing the non-Newtonian behavior of the flow. An unstructured finite volume method combined with a fractional-step projection method is developed for the discretization of incompressible equations governing the non-Newtonian flows. The important flow dynamics related with the arterial diseases, such as the wall shear stress and vortex generation, are also numerically studied in detail. Numerical results reveal that there are marked differences between Newtonian and non-Newtonian models.

关键词： double constrictions power-law fluid finite volume method unstructured grids

Influences of Cooling Rate After Solution Treatment on Microstructural Evolution and Mechanical Properties of Superalloy Rene 80

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Acta Metallurgica Sinica(English Letters) 2017年第3期30卷 261-271页

作者： Shuang gao Jie-Shan hou Kai-Xin Dong lan-Zhang Zhou Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Influences of the cooling rate after solution treatment on microstructural evolution and mechanical properties of Rene 80 nickel-based superalloy were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and mechanical test. Results showed that the high cooling rate decreased the size of secondary γ＇particles in the supersaturated matrix, but led to a high coarsening rate of γ＇ particles during subsequent aging treatment. Despite various coarsening rates, the size and morphology of γ＇ particles in the final microstructures of all samples were close due to the long enough holding time to an equilibrium state. During the aging of 870 ℃/2 h, primary MC started to decompose with the carbide reaction： MC ＋ γ＇ --＊ MrC or M23C6 -t- γ＇. And a number of observations showed that the coarsening of γ＇ particles on grain boundaries resulted in the depletion of γ＇ during aging treatment. The test results indicated that high cooling rate resulted in the presence of quench crack, and the air cooling method following solution treatment was an optimum heat treatment method for Rene 80.

关键词： Ni-based superalloy Cooling rate Precipitates Ripening theory Heat treatment Microstructural evolution

Synthesis,Structure and Luminescence of Zn_(4.5)Cu_3 Heteronuclear Coordination Polymer Comprising Macrocyclic Oxamide and 5-Sulfosalicylic Ion

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Chemical Research in Chinese Universities 2010年第4期26卷 501-504页

作者： SUN ya-qiu WANG Jing FAN lan-lan gao Dong-zhao Tianjin Key Laboratory of Structure and Performance for Functional Molecule College of Chemistry and Life Science Tianjin Normal University Tianjin 300387 P. R. China

The complex [Zn4.5（SSA）3（CuL）3（H2O）6]n was synthesized and structurally determined, where SSA is fully deprotonated 5-sulfosalicylic acid（CuL, H2L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca- 7,13-dien）. The title complex crystallized in the triclinic system with space group P1^-, a=1.19788（17） nm, b=1.4253（2） nm, c=2.2890（4） nm, α=90.211（2）°, ,β=93.076（2）°, γ=90.600（2）°. The complex displayed a 1D ladderlike chain. All these 1D chains were further interlinked via hydrogen bonds, resulting in a 2D architecture. The luminescent property of the compound was also discussed.

关键词： Heteronuclear complex Macrocyclic oxamide Luminescence