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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1398-1406页

作者： Zeli Jia Xiaomeng Fan Jiangyi He jimei xue Fang Ye Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Xi’an Xinyao Ceramic Composite Materials Co. Ltd.Xi’an 710117China

A polymer-derived ZrC ceramic with excellent electromagnetic interference(EMI)shielding performance was developed to meet ultra-high temperature *** thermal decomposition process of ZrC organic precursor was studied to reveal the evolution of phase composition,microstructure,and EMI shielding ***,the carbothermal reduction reaction occurred at 1300℃,and the transition from ZrO_(2) to ZrC was completed at 1700℃.With the increase in the annealing temperature,the tetragonal zirconia gradually transformed into monoclinic zirconia,and the transition was completed at the annealing temperature of 1500℃ due to the consumption of a large amount of the carbon *** average total shielding effectiveness values were 11.63,22.67,22.91,22.81,and 34.73 dB when the polymerderived ZrC was annealed at 900,1100,1300,1500,and 1700℃,*** the thermal decomposition process,the graphitization degree and phase distribution of free carbon played a dominant role in the shielding *** typical core–shell structure composed of carbon and ZrC can be formed at the annealing temperature of 1700℃,which results in excellent shielding performance.

关键词： ZrC ceramics polymer-derived ceramic phase composition electromagnetic interference shielding

Failure behavior of interfacial domain in SiC-matrix based composites

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Journal of Materials Science & Technology 2021年第29期88卷 1-10页

作者： Jinxue Ding Xiaokang Ma Xiaomeng Fan jimei xue Fang Ye Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi'an710072China

In this work,the microstructure,failure behavior and interfacial properties with respective to the interfacial domain in SiCf/BN/SiC and C_(f)/PyC/SiC composites were studied via the fiber push-in *** differences in the mechanical response of the interfacial domain were *** the fiber push-in test for SiCf/BN/SiC,the interface debonding accompanied with interphase fracture occurred,resulting in an obvious sign of the onset of debonding on loading-displacement(P-u)*** the good continuity of P-u curves can be observed for Cf/PyC/SiC,which is due to that the failure is in the form of interface debonding along with interphase lateral slipping caused by the extension of buckled carbon fiber,without any interphase *** interfacial properties calculated from the fiber push-in test show that Cf/PyC/SiC possesses a weaker interfacial domain compared with SiC_(f)/BN/*** interfacial shear stress of SiCf/BN/SiC and C_(f)/PyC/SiC composites amounts 94.2 and 48.1 MPa,respectively.

关键词： SiC-matrix based composites Interfacial domain Fiber push-in test Failure behavior Interfacial mechanical properties

Controllable synthesis of mesoporous carbon hollow microsphere twined by CNT for enhanced microwave absorption performance

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Journal of Materials Science & Technology 2020年第24期59卷 164-172页

作者： Minghang Li Xiaomeng Fan Hailong Xu Fang Ye jimei xue Xiaoqiang Li Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

The low dielectric loss of mesoporous carbon hollow microsphere(PCHM)requires high filler loading(higher than 20 wt%)when it is used as microwave *** order to decrease the filler loading of PCHM,a new strategy for synergistic increase of polarization and conductive loss was developed by twining PCHM with carbon nanotube(CNT)according to theoretic *** the optimization of CNT content,the minimum reflection coefficient was -34.6 dB with a filler loading of only 10 wt%,which was much lower than -2.1 dB of *** addition,the effective absorption bandwidth was 3.6 GHz at X band with a thickness of 2.8 *** enhanced microwave absorption performance can be ascribed to the unique combination of hollow PCHM and one-dimensional CNT with higher graphitization degree,leading to increase of conductivity and heterogeneous *** a result,the conductive loss increased from 0.12 to 2.27 and polarization loss increased from 0.15 to 0.67,achieving the balance between attenuation ability and impedance match.

关键词： Microwave absorption Interfacial polarization Carbon Polarization loss

The enhanced mechanical properties of SiC nanowires/Ba_(0.75)Sr_(0.25)Al_(2)Si_(2)O_(8) ceramics with embedded SiO_(2) interface

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Journal of Advanced Ceramics 2024年第7期13卷 933-941页

作者： Xin Li Xiaomeng Fan Haojie Luo Xiaoke Lu jimei xue Fang Ye Yongsheng Liu Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

In this work,low-softening-temperature and low-modulus SiO_(2) was introduced as an embedded interface between SiC nanowires(SiCnws)and a Ba_(x)Sr_(1−x)Al_(2)Si_(2)O_(8) ceramic matrix to enhance strength and toughness of the *** the sintering process,molten SiO_(2) enhances the flowability of the ceramic powders and modifies the dispersion of *** strengthening effect of SiCnws was fully realized,and the flexural strength of the optimized ceramics reached 193±16 MPa,which represents an increase of 52.6%.After the formation of the embedded SiO_(2) interface with a low modulus,cracks can deflect along the SiCnws surface,which is consistent with the criterion of He and *** can effectively extend the crack propagation path,and the fracture toughness(K_(IC))is thus improved by 94.0%,reaching 3.1±0.5 MPa·m^(1/2).

关键词： multiphase ceramics SiO_(2) interface densification mechanical properties

Oxidation behaviors of carbon fiber reinforced multilayer SiC–Si_(3)N_(4) matrix composites

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Journal of Advanced Ceramics 2022年第2期11卷 354-364页

作者： Xiaolin DANG Donglin ZHAO Tong GUO Xiaomeng FAN jimei xue Fang YE Yongsheng LIU Laifei CHENG Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201203China

Oxidation behaviors of carbon fiber reinforced SiC matrix composites(C/SiC)are one of the most noteworthy *** C/SiC,the oxidation behavior was controlled by matrix microcracks caused by the mismatch of coefficients of thermal expansion(CTEs)and elastic modulus between carbon fiber and SiC *** order to improve the oxidation resistance,multilayer SiC–Si_(3)N_(4) matrices were fabricated by chemical vapor infiltration(CVI)to alleviate the above two kinds of mismatch and change the local stress *** the oxidation of C/SiC with multilayer matrices,matrix microcracks would be deflected at the transition layer between different layers of multilayer SiC–Si_(3)N_(4) matrix to lengthen the oxygen diffusion channels,thereby improving the oxidation resistance of C/SiC,especially at 800 and 1000℃.The strength retention ratio was increased from 61.9%(C/SiC–SiC/SiC)to 75.7%(C/SiC–Si_(3)N_(4)/SiC/SiC)and 67.8%(C/SiC–SiC/Si_(3)N_(4)/SiC)after oxidation at 800℃for 10 h.

关键词： carbon fiber reinforced SiC matrix composites(C/SiC) multilayer Si_(3)N_(4)matrices elastic modulus mismatch coefficient of thermal expansion(CTE)mismatch oxidation resistance

Electromagnetic interference shielding Ti3C2Tx-bonded carbon black films with enhanced absorption performance

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Chinese Chemical Letters 2020年第4期31卷 1026-1029页

作者： Xiaomeng Fan Minghang Li Xin Li Fang Ye jimei xue Litong Zhang Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi'an 710072China

The demand for flexible and freestanding electromagnetic interference(EMI)shielding materials are more and more urgent to combat with serious electromagnetic(EM)radiation *** Ti3C2Tx is considered as promising EMI shielding material to graphenes because of the low cost and high electrical ***,the shielding performance still needs to be optimized to decrease the reflection effectiveness(SER)and increase absorption effectiveness(SEA).Herein,we prepared Ti3C2Tx-bonded carbon black films with a porous *** SER decreased from 20 dB to12 dB and the SEA increased from 31 dB to 47 *** best EMI shielding effectiveness can be as high as60 dB with SEA of 15 dB and SER of45 *** calculated specific shielding effectiveness can be as high as8718 dB cm^2/*** results indicate that the porous structure can enhance the absorption of the EMI shielding films,resulting from the enhanced scattering and reflectio *** ntly,this work provides a promising MXene-based EMI shielding film with lightweight and flexibility.

关键词： Carbon black MXenes Film Electromagnetic interference shielding Flexible

A SiC nanowires/Ba_(0.75)Sr_(0.25)Al_(2)Si_(2)O_(8) ceramic heterojunction for stable electromagnetic absorption under variable-temperature

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Journal of Materials Science & Technology 2022年第30期125卷 29-37页

作者： Xin Li Xiaoke Lu Minghang Li jimei xue Fang Ye Xiaomeng Fan Yongsheng Liu Laifei Cheng Litong Zhang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

The application of semiconductor materials was limited as electromagnetic absorption materials,due to the unstable absorption performance caused by the temperature *** this work,a structurally controllable ceramic heterojunction was developed by assembling structural units of SiC nanowires(SiCnws)and Ba_(0.75)Sr_(0.25)Al_(2)Si_(2)O_(8)(BSAS).Benefiting from the optimization of the energy gap and the construction of heterogeneous interfaces,the ceramic heterojunction can achieve stable electromagnetic absorption from room temperature to 600℃,the effective absorption bandwidth is almost *** the minimum reflection loss value reached-63.6 dB at 600℃.Meanwhile,the SiCnws/BSAS ceramic heterojunction shows stable electromagnetic absorption performance in various simulated outdoor environments,including acid rain,seawater,high temperature and water vapor *** result provides a fire-new idea to realize the environmental adaptability of electromagnetic absorption materials and largely broadens its application prospect.

关键词： Ceramic heterojunction Energy gap regulation Polarization effect Stable electromagnetic absorption Variable-temperature Environment adaptability

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen xue-Jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU Lin LI xue XIE Jun DONG Ming School of Energy and Power Engineering Dalian University of Technology School of Optical Information and Energy Engineering Wuhan Institute of Technology School of Energy and Environment Shenyang Aerospace University

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method（LES-DEM） *** validity of the LES approach was verified by comparison with available direct numerical simulation（DNS） *** adopted the Johnson-Kendall-Roberts（JKR） contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters（dp=2-20 μm） in the laminar and transition of shear layer（TrSL） flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise（y-direction）.With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： discrete element method large eddy simulation microparticle particle agglomeration

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： Li Ma Cai Dai Xingsi xue Cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy