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Interfacial stress transfer behavior in a specially-shaped fiber/matrix pullout test 被引量:2
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作者 Y. R. Zhao Y. M. Xing +1 位作者 Z. K. Lei F. C. Lang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期113-119,共7页
Specially designed fibers are widely used in engineering practice because the specially-designed shape can help to improve the bonding strength of the fiber and the interface. Studied in this paper is the interfacial ... Specially designed fibers are widely used in engineering practice because the specially-designed shape can help to improve the bonding strength of the fiber and the interface. Studied in this paper is the interfacial shear stress transfer behavior on both sides of the specially designed fiber when it is being pulled out; in which automatic analysis of three-dimensional photoelasticity is employed and the finite element method is adopted. The results show that the stress transfer occurs mainly in the region near the fiber's embedded end where the stress reaches its critical point, leading to debonding of the interface. Before debonding, as the pullout loading increases, the peak value of shear stress transfers along the fiber from the embedded end to the interior of the matrix, and then stops at the hooked part of the fiber because of its impediment. When the interface begins to debond as the load increases, the shear stress can be transferred to the hooked part. 展开更多
关键词 fiber-reinforced composites Specially-shaped fiber Interfacial stress transfer Photo-elasticity - FEM
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Mechanical properties and wear behavior of extruded basalt fibers/7075 aluminum matrix composites used for drill pipes
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作者 MA Yin-long SUN Zhi-gang +3 位作者 XIONG Hong-wei REN Jie ZHAO Jing-jing GUO Cheng-bin 《Journal of Central South University》 2025年第1期21-33,共13页
Basalt fibers/7075 aluminum matrix composites were studied to meet the demand of aluminum alloy drill pipes for material wear resistance.The composites with different basalt fiber additions were prepared by hot presse... Basalt fibers/7075 aluminum matrix composites were studied to meet the demand of aluminum alloy drill pipes for material wear resistance.The composites with different basalt fiber additions were prepared by hot pressed sintering and hot extrusion.The mechanical properties as well as friction and wear properties of the composites were studied by microstructure analysis,tensile experiments,friction and wear experiments.The results showed that basalt fibers were oriented and uniformly distributed and led to local grain refinement in the alloy matrix.The hardness and elongation of the composites were improved.The friction coefficient of the composites increased and then decreased,and the maximum wear depth and wear amount decreased,then increased,then decreased again with the growth of basalt fiber addition.Meanwhile,the inclusion of basalt fibers mitigated the uneven wear of the extruded 7075 aluminum alloy.The value of wear depth difference of 7075-0.2BF was the smallest,and that of 7075-2.0BF was close to it.The maximum wear depth and wear volume the 7075-0.2BF and 7075-2.0BF were also the smallest.The inhibition of uneven wear by basalt fibers enhanced of wear resistance for 7075 aluminum alloy,which has reference significance for improving the performance of aluminum alloy drill pipes. 展开更多
关键词 aluminum matrix composites basalt fibers mechanical properties wear behavior
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Fiber reinforced ceramic matrix composites:from the controlled fabrication to precision machining
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作者 Shuoshuo Qu Yuying Yang +3 位作者 Peng Yao Luyao Li Yang Sun Dongkai Chu 《International Journal of Extreme Manufacturing》 2025年第6期118-150,共33页
Fiber reinforced ceramic matrix composites(FRCMCs)are the preferred materials for safety critical components in the fields of aerospace,nuclear engineering,and transportation,with broad market and application prospect... Fiber reinforced ceramic matrix composites(FRCMCs)are the preferred materials for safety critical components in the fields of aerospace,nuclear engineering,and transportation,with broad market and application prospects.However,due to the characteristics of multiphase,heterogeneity,and anisotropy,key issues such as poor adhesion,high porosity,and crack propagation urgently need to be addressed in the fabrication and machining of FRCMCs.With the increasing demand for FRCMCs parts,high-quality and reliable design and fabrication,performance evaluation,and precision manufacturing have become a series of hot issues.There is a lack of systematic review in capturing the current research status and development direction of FRCMCs fabrication and machining.This research aims to comprehensively review and critically evaluate the existing understanding of the fabrication and machining of FRCMCs.This study can provide scientists with a deeper understanding of the shape control mechanism of FRCMCs fabrication and machining,the theoretical basis of material synchronous removal,machining performance,and development direction.Firstly,the basic characteristics and application background of FRCMCs are introduced.Secondly,by comparing and analyzing the typical fabrication process of FRCMCs,the advantages,disadvantages,and performance evaluation of different processes are comprehensively evaluated.Thirdly,the material removal mechanisms and machining performance evaluation standards of traditional mechanical machining technologies(drilling,milling,grinding)and non-traditional mechanical machining technologies(ultrasonic,laser,water jet,discharge,wire saw,and multi-field hybrid machining)are discussed and analyzed.Finally,the challenges,development trends,and prospects faced by FRCMCs in the fields of fabrication,machining,and application are analyzed.This study not only elucidates the basic processes and key difficulties in the fabrication of FRCMCs,but also provides valuable insights for low-damage machining. 展开更多
关键词 fiber reinforced ceramic matrix composites removal mechanism traditional mechanical machining technologies non-traditional mechanical machining technologies
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Increasing the strength of carbon nanotube fibers and their use as a polishing medium
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作者 Xue Zhiping Lu Jing Huang Hui 《新型炭材料(中英文)》 北大核心 2026年第1期209-221,共13页
We report a method for increasing the mechanical strength of carbon nanotube(CNT)fibers while enabling the uniform adhesion of cerium oxide(CeO_(2))abrasive particles to them using polyethyleneimine(PEI).Results show ... We report a method for increasing the mechanical strength of carbon nanotube(CNT)fibers while enabling the uniform adhesion of cerium oxide(CeO_(2))abrasive particles to them using polyethyleneimine(PEI).Results show that 5%of PEI increases the tensile strength of CNT fibers by approximately 175%.CeO_(2) particles were uniformly deposited on the reinforced CNT fibers by electrophoretic deposition.A flexible polishing tool was fabricated by weaving the CeO_(2)-CNT fibers into a non-woven fabric substrate.When used to polish potassium dihydrogen phosphate crystals,the tool reduced the surface roughness from 200 to 7.6 nm within 10 min.This approach has potential use for the development of new precision processing tools. 展开更多
关键词 CNT fiber Tensile strength Electrophoretic deposition Polishing tool Surface roughness
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Effect of Argon Atmosphere Heat Treatment on Mechanical Properties and Microstructural Evolution of Shicolon-Ⅱ SiC Fibers
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作者 YUAN Wang HU Jianbao +3 位作者 ZHOU Liang KAN Yanmei ZHANG Xiangyu DONG Shaoming 《无机材料学报》 北大核心 2026年第1期119-128,共10页
Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate indiv... Silicon carbide fibers are considered ideal reinforcing materials for ceramic matrix composites due to their excellent mechanical properties and high-temperature performance.Different types of fibers necessitate individual investigation due to variations in their composition and fabrication processes.This study presents a comprehensive investigation into evolution of the mechanical properties,surface microstructure,and composition of Shicolon-Ⅱ fibers subjected to argon heat treatment at temperatures ranging from 1300℃to 1700℃.The Shicolon-Ⅱ fibers are composed of small-sized β-SiC grains,SiC_(x)O_(y) amorphous phase,and a minor amount of graphite microcrystals.Following treatment in an argon atmosphere at 1300℃,the fibers maintain a monofilament tensile strength of 3.620 GPa,corresponding to a retention of 98.32%.This strength diminishes to 2.875 GPa,equating to a retention of 78.08%,after treatment at 1500℃.The reduction in mechanical properties of the fibers can be ascribed to the decomposition of the amorphous phase and the growth of β-SiC grains.Furthermore,creep resistance is an essential factor influencing the long-term performance of composite materials.After treatment at temperatures above 1400℃,the high-temperature creep resistance of the fibers is significantly enhanced due to growth of β-SiC grains.This study offers valuable theoretical insights into high-temperature applications of second-generation fibers,contributing to an enhanced understanding of their performance under extreme conditions. 展开更多
关键词 Shicolon-ⅡSiC fiber heat treatment mechanical property MICROSTRUCTURE
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Broadband high-coherence supercontinuum in Al_(0.24)Ga_(0.76)As photonic crystal fibers
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作者 XIA Yong-tao HOU Shang-lin +4 位作者 FENG Yun-long XIE Cai-jian LEI Jing-li WU Gang YAN Zu-yong 《中国光学(中英文)》 北大核心 2026年第1期164-178,共15页
An alternative elliptical and circle air-hole-assisted Al_(0.24)Ga_(0.76)As photonic crystal fiber(PCF)was proposed for generating broadband high-coherence mid-infrared supercontinuum,and the dispersion,effect-ive mod... An alternative elliptical and circle air-hole-assisted Al_(0.24)Ga_(0.76)As photonic crystal fiber(PCF)was proposed for generating broadband high-coherence mid-infrared supercontinuum,and the dispersion,effect-ive mode area and nonlinear coefficient were investigated by using finite element method(FEM),the evolu-tion of optical pulses propagating along the fiber was simulated,and the supercontinuum and the coherence were analyzed and evaluated under different pumping conditions.The results show that a supercontinuum spectrum with a spectral width of 4.852μm can be obtained in the proposed fiber with d_(1)/Λof 0.125,d_(2)/Λof 0.583 and the zero-dispersion wavelength of 3.228μm by pumping with a Gaussian pulse with a peak power of 800 W and a full width at half maximum(FWHM)of 20 fs at wavelength of 3.3μm.When the fiber is pumped by the pulse with the peak power of 2000 W,the FWHM of 80 fs at the wavelength of 4.0μm in the in the anomalous dispersion region,the modulation instability is obviously suppressed,and the high-coher-ence supercontinuum spectrum spanning from 1.1μm to 8.99μm is observed.A part of the pulse energy is transferred to the anomalous dispersion region when pumped at the wavelength of 2.8μm in the normal dis-persion region and a broadband high-coherence supercontinuum spectrum extending from 0.8μm to 9.8μm is generated in the 10 mm proposed fiber.This paper introduces elliptical air holes in the Al_(0.24)Ga_(0.76)As photonic crystal fiber,which enhances flexibility for tailoring the performance of supercontinuum,ultimately achieving the broadest supercontinuum spectrum with the shortest fiber length to date. 展开更多
关键词 SUPERCONTINUUM photonic crystal fiber COHERENCE Al_(0.24)Ga_(0.76)As
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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A New Image Encryption Algorithm Based on Cantor Diagonal Matrix and Chaotic Fractal Matrix
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作者 Hongyu Zhao Shengsheng Wang 《Computers, Materials & Continua》 2026年第1期636-660,共25页
Driven by advancements in mobile internet technology,images have become a crucial data medium.Ensuring the security of image information during transmission has thus emerged as an urgent challenge.This study proposes ... Driven by advancements in mobile internet technology,images have become a crucial data medium.Ensuring the security of image information during transmission has thus emerged as an urgent challenge.This study proposes a novel image encryption algorithm specifically designed for grayscale image security.This research introduces a new Cantor diagonal matrix permutation method.The proposed permutation method uses row and column index sequences to control the Cantor diagonal matrix,where the row and column index sequences are generated by a spatiotemporal chaotic system named coupled map lattice(CML).The high initial value sensitivity of the CML system makes the permutation method highly sensitive and secure.Additionally,leveraging fractal theory,this study introduces a chaotic fractal matrix and applies this matrix in the diffusion process.This chaotic fractal matrix exhibits selfsimilarity and irregularity.Using the Cantor diagonal matrix and chaotic fractal matrix,this paper introduces a fast image encryption algorithm involving two diffusion steps and one permutation step.Moreover,the algorithm achieves robust security with only a single encryption round,ensuring high operational efficiency.Experimental results show that the proposed algorithm features an expansive key space,robust security,high sensitivity,high efficiency,and superior statistical properties for the ciphered images.Thus,the proposed algorithm not only provides a practical solution for secure image transmission but also bridges fractal theory with image encryption techniques,thereby opening new research avenues in chaotic cryptography and advancing the development of information security technology. 展开更多
关键词 Image encryption spatiotemporal chaotic system chaotic fractal matrix cantor diagonal matrix
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Ionic Liquid-regenerated Cellulose Fiber:A Promising Next Generation Regenerated Cellulose Fiber
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作者 Xin-Yu Wang Kun-Kun Zhu +5 位作者 Min Zhang Yong-Xin Wei Jing-Jing Yuan Jin-Ming Zhang Jin-Feng Wang Jun Zhang 《Chinese Journal of Polymer Science》 2026年第1期21-29,I0008,共10页
As the global textile industry has accelerated its transition to a circular economy,iterative innovation in regenerated cellulose fibers has become a key industry focus.With viscose fiber having been industrialized fo... As the global textile industry has accelerated its transition to a circular economy,iterative innovation in regenerated cellulose fibers has become a key industry focus.With viscose fiber having been industrialized for over a century and lyocell fiber gaining market recognition because of its environmentally friendly process,which is the next regenerated cellulose fiber.Herein,ionic liquids with low vapor pressure,nonflammability,relatively simple recovery,and high dissolution efficiency were used to fabricate regenerated cellulose fibers.The viscose and lyocell properties of the fibers were systematically compared,including microscopic morphology,dyeing behavior,fibrillation resistance,mechanical properties,yarn-forming capacity,and fabric performance.The ionic liquid(IL)fiber exhibited a smooth surface and circular cross-section,with the highest tensile strength,moderate dyeing and fibrillation properties,and similar spinning and weaving performance.This work can provide a reference for the commercial application of regenerated cellulose fibers fabricated from ionic liquid. 展开更多
关键词 CELLULOSE Ionic liquid fiber VISCOSE LYOCELL
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Smart fiber photodetectors based on inorganic semiconductors
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作者 Hongyun Peng Fangfang Xia +2 位作者 Zhigang Xia Huiqiao Li Tianyou Zhai 《Science China Materials》 2026年第3期1249-1264,共16页
Fiber photodetectors(FPDs)with high deformability,flexible designability,and seamless integrability with everyday textiles hold tremendous potential for the nextgeneration wearable optoelectronics.Inorganic semiconduc... Fiber photodetectors(FPDs)with high deformability,flexible designability,and seamless integrability with everyday textiles hold tremendous potential for the nextgeneration wearable optoelectronics.Inorganic semiconductors(ISCs)are considered the ideal building block to design and govern the functions of FPDs owing to their superior electrical and optical properties.Recent developments in wearable technology of ISCs,especially in fiber form factor,have driven the creation of various FPDs with smart capabilities,from light sensing,information interfacing,to sophisticated logic operating,revolutionizing human-machine interaction paradigms in many emerging fields.Herein,we present a comprehensive review of the recent progress of ISCbased FPDs.Firstly,key design principles for ISC-based FPDs are explored,encompassing material selection,fabrication technologies,device architectures,and textile integration strategies.Then,how defect engineering,alignment engineering,and heterojunction engineering of ISCs can control the optoelectronic performance of FPDs is examined.Following this,potential wearable applications of ISC-based FPDs in optical communication,image sensing,and health monitoring are analyzed.Finally,the challenges and perspectives for the design of high-performance ISC-based FPDs are outlined. 展开更多
关键词 inorganic semiconductors fiber optoelectronics wearable electronics
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Differential plasticity of excitatory and inhibitory reticulospinal fibers after spinal cord injury:Implication for recovery
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作者 Rozaria Jeleva Carmen Denecke Muhr +1 位作者 Alina P.Liebisch Florence M.Bareyre 《Neural Regeneration Research》 2026年第5期2011-2020,共10页
The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory ... The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory fibers.While the reticulospinal tract has been shown to be particularly prone to axonal growth and plasticity following injuries of the spinal cord,the differential capacities of excitatory and inhibitory fibers for plasticity remain unclear.As adaptive axonal plasticity involves a sophisticated interplay between excitatory and inhibitory input,we investigated in this study the plastic potential of glutamatergic(vGlut2)and GABAergic(vGat)fibers originating from the gigantocellular nucleus and the lateral paragigantocellular nucleus,two nuclei important for locomotor function.Using a combination of viral tracing,chemogenetic silencing,and AI-based kinematic analysis,we investigated plasticity and its impact on functional recovery within the first 3 weeks following injury,a period prone to neuronal remodeling.We demonstrate that,in this time frame,while vGlut2-positive fibers within the gigantocellular and lateral paragigantocellular nuclei rewire significantly following cervical spinal cord injury,vGat-positive fibers are rather unresponsive to injury.We also show that the acute silencing of excitatory axonal fibers which rewire in response to lesions of the spinal cord triggers a worsening of the functional recovery.Using kinematic analysis,we also pinpoint the locomotion features associated with the gigantocellular nucleus or lateral paragigantocellular nucleus during functional recovery.Overall,our study increases the understanding of the role of the gigantocellular and lateral paragigantocellular nuclei during functional recovery following spinal cord injury. 展开更多
关键词 GABAergic(vGat)fibers gait features glutamatergic(vGlut2)fibers PLASTICITY recovery of function reticulospinal tract spinal cord injury
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Simulation of the Specific Contributions of Molecular Weight,Orientation Degree,and Crystallinity to the Tensile Mechanics of Polyethylene Fibers
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作者 Tian-Hao Yang Jing-Han Wu +4 位作者 Ming-Ming Ding Wen Zhai Ke Wang Qiang Fu Yang Liu 《Chinese Journal of Polymer Science》 2026年第2期560-575,I0018,共17页
UHMWPE fibers exhibit impressive modulus and strength,but they have not reached their theoretical limits.Researchers focus on molecular weight,orientation,and crystallinity of UHMWPE,yet their contributions to mechani... UHMWPE fibers exhibit impressive modulus and strength,but they have not reached their theoretical limits.Researchers focus on molecular weight,orientation,and crystallinity of UHMWPE,yet their contributions to mechanical properties are unclear.Molecular dynamics simulations are valuable but often limited by computational constraints.Our aim is to simulate higher molecular weights to better represent real UHMWPE fibers.We used Packmol and Polyply methodologies to construct PE systems,with Polyply reproducing more reasonable properties of UHMWPE fibers.Additionally,tensile simulations showed that orientation and crystallinity greatly impact Young's modulus more than molecular weight.Energy decomposition indicated that higher molecular weights lead to covalent bonds that can withstand more energy during stretching,thus increasing breaking strength.Combining simulations with machine learning,we found that orientation has the most significant impact on Young's modulus,contributing 60%,and molecular weight plays the most crucial role in determining the breaking strength,accounting for 65%.This study provides a theoretical basis and guidelines for enhancing UHMWPE's modulus and strength. 展开更多
关键词 Molecular dynamics simulation Polyethylene fiber Mechanical properties
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Cancer cell-dependent increase in senescence-like populationsfollowing exosome treatment:The role of extracellular matrix andcellular glycocalyx
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作者 Ilya D Klabukov Anastas Kisel +2 位作者 Elena Yatsenko Yana Sulina Denis S Baranovskii 《World Journal of Stem Cells》 2026年第1期108-111,共4页
We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-l... We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-like state withoutapoptosis.The results obtained by the authors highlight the features of theeffects of senescent drift induction in surrounding tissues.In the light of thesefindings,the role of the properties of extracellular matrix and cellular glycocalyxin responses of human tumors to therapy remain uninvestigated.These extracellularbarriers appear to be significant obstacles to effective cancer therapy,especiallyin relation to the use of unique properties of tumor microenvironment forthe immunotherapy-resistant cancer treatment. 展开更多
关键词 Cancer Extracellular matrix GLYCOCALYX EXOSOMES Extracellular vesicles Tumor microenvironment
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Matrix effect of hydroxycinnamic acids on chromatic properties and phenolic profile of Cabernet Sauvignon dry red wine
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作者 Lulu Wu Yu Zhang +5 位作者 Mario Prejanò Tiziana Marino Nino Russo Guojie Jin Yongsheng Tao Yunkui Li 《Journal of Integrative Agriculture》 2026年第1期339-351,共13页
The effect of adding hydroxycinnamic acids(caffeic acid,sinapic acid,p-coumaric acid and chlorogenic acid)in Cabernet Sauvignon dry red wine before and after fermentation was investigated,taking into account the color... The effect of adding hydroxycinnamic acids(caffeic acid,sinapic acid,p-coumaric acid and chlorogenic acid)in Cabernet Sauvignon dry red wine before and after fermentation was investigated,taking into account the color parameters,anthocyanin content,and overall polyphenol levels in the wine samples.The copigmentation effect of malvidin-3-Oglucoside and sinapic acid was further explored in model solution and through theoretical calculations.The results indicated that the addition of hydroxycinnamic acids significantly enhanced the wine's color with sinapic acid(before the fermentation)showing the most pronounced color protection effect.Compared to control samples,the addition of hydroxycinnamic acids resulted in a 36%increase in total phenolic content and a 28% increase in total anthocyanin content.Thermodynamic analysis revealed that the interaction between sinapic acid and malvidin-3-O-glucoside was spontaneous and exothermic.Theoretical studies identified hydrogen bonding(HB)and dispersion forces as the main primary stabilizing forces,with the carboxyl group of sinapic acid playing a critical role while the anthocyanin backbone also influenced the interaction. 展开更多
关键词 matrix effect dry red wine POLYPHENOL hydroxycinnamic acids anthocyanins
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A Kind of Fast Iterative Methods With the Application Based on Diagonal Matrix Splitting
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作者 XU Qiuyan 《宁夏大学学报(自然科学版中英文)》 2026年第1期1-13,共13页
The fast solution of linear equations has always been one of the hot spots in scientific computing.A kind of the diagonal matrix splitting iteration methods are provided,which is different from the classical matrix sp... The fast solution of linear equations has always been one of the hot spots in scientific computing.A kind of the diagonal matrix splitting iteration methods are provided,which is different from the classical matrix splitting methods.Taking the decomposition of the diagonal elements for coefficient matrix as the key point,some new preconditioners are constructed.Taking the tri-diagonal coefficient matrix as an example,the convergence domains and optimal relaxation factor of the new method are analyzed theoretically.The presented new iteration methods are applied to solve linear algebraic equations,even 2D and 3D diffusion problems with the fully implicit discretization.The results of numerical experiments are matched with the theoretical analysis,and show that the iteration numbers are reduced greatly.The superiorities of presented iteration methods exceed some classical iteration methods dramatically. 展开更多
关键词 ITERATION matrix splitting diffusion equation CONVERGENCE optimal relaxation factor
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Influence of ultrasonic agitation on dispersion of fibers in a shell mold for investment casting
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作者 Zhi-cheng Feng Kai Lü +2 位作者 Yan Lu Wen-bo Jin Lei Che 《China Foundry》 2026年第1期108-116,共9页
To develop a suitable production process for fiber reinforced investment casting shell mold,three methods were studied:the traditional method(M_(1)),the method of adding fiber into silica sol with mechanical stirring ... To develop a suitable production process for fiber reinforced investment casting shell mold,three methods were studied:the traditional method(M_(1)),the method of adding fiber into silica sol with mechanical stirring and ultrasonic agitation(M_(2)),and the method of adding fiber into slurry with mechanical stirring and ultrasonic agitation for durations of 3,15,30,and 45 min(M_(3)).The bending strength,high-temperature self-load deformation,and thermal conductivity of the shell molds were investigated.The results reveal that the enhancement of fiber dispersion through ultrasonic agitation improves the comprehensive performance of the shell molds.The maximum green bending strength of the shell mold by M_(2) reaches 3.29 MPa,which is 29% higher than that of the shell mold prepared by M_(1).Moreover,the high-temperature self-load deformation of the shell mold is reduced from 0.62% to 0.44%.In addition,simultaneous ultrasonic agitation and mechanical stirring effectively shorten the slurry preparation time while maintaining comparable levels of fiber dispersion.With the process M_(3)-45 min,the fillers are uniformly dispersed in the slurry,and the fired bending strength and the high-temperature self-load deformation reach 6.25 MPa and 0.41%,respectively.Therefore,the proposed ultrasonic agitation route is promising for the fabrication of fiber-reinforced shell molds with excellent fibers dispersion. 展开更多
关键词 investment casting steel fibers fiber-reinforced shell ultrasonic agitation thermal conductivity
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Spatially decoupled single/dual-atomic sites with independent bifunctional activity for high-performance fiber zinc-air batteries
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作者 Jing Zhou Yumin Chen +13 位作者 Wei Mao Long Jiang Huangjian Chen Yunzhan Ying Yulong Wan Shifan Zheng Ju Lin Shikun Liang Yuyuan Yao Bingjie Wang Ye Zhang Lihua Gan Huisheng Peng Lie Wang 《Science China Materials》 2026年第3期1581-1589,共9页
The development of high-performance bifunctional electrocatalysts is crucial for advancing zinc-air batteries.However,the fundamentally distinct mechanisms of the oxygen reduction and evolution reactions(ORR/OER)hinde... The development of high-performance bifunctional electrocatalysts is crucial for advancing zinc-air batteries.However,the fundamentally distinct mechanisms of the oxygen reduction and evolution reactions(ORR/OER)hinder the simultaneous realization of high activity within a single catalyst.Herein,we propose a spatial decoupling strategy to overcome this limitation by engineering isolated Fe singleatoms and Fe-Ir dual-atom pairs on a nitrogen-doped carbon matrix(Fe/FeIr-NC).In this architecture,Fe single atoms serve as ORR centers,while Fe-Ir pairs with tunable spacing are tailored for OER,enabling complete functional separation and independent optimization of the reactions.As a result,the catalyst delivers an ORR half-wave potential of 0.91 V and an OER overpotential of 250 mV at 10 mA cm^(-2),yielding a record-low bifunctional gap(ΔE=0.57 V)that outperforms all reported single-and dual-atom catalysts.A flexible fiber zincair battery was developed based on this catalyst,delivering a peak power density of 3920 W kg^(-1),along with a 1.4-fold increase in energy efficiency and a 2.6-fold extension in cycle life compared to the commercial Pt/C+IrO_(2)benchmark.This work not only breaks the traditional activity trade-off in bifunctional catalysis but also offers a promising route toward high-performance power sources for wearable electronics. 展开更多
关键词 fiber zinc-air batteries bifunctional electrocatalysts flexible energy-storage devices wearable electronics
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Strain localization and time-dependent deformation in granodiorite characterized by distributed optical fiber sensing
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作者 Shuting Miao Arno Zang +3 位作者 Guido Blöcher Yinlin Ji Hannes Hofmann Pengzhi Pan 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期166-178,共13页
A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relax... A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relaxation.Distributed optical fiber sensing was used to measure strains across the sample surface by helically wrapping the single-mode fiber around the cylindrical sample.Close agreement was observed between the circumferential strains obtained from the optical fibers and the extensometer.The reconstructed full-field strain contours show strain heterogeneity from the crack closure phase,and the strains in the later deformation phase are dominantly localized within the former high-strain zone.The Gini coefficient was used to quantify the degree of strain localization and shows an initial increase during the crack closure phase,a decrease during the linear elastic phase,and a subsequent increase during the post-yielding phase.This behavior corresponds to a process of initial localization from an imperfect boundary condition,homogenization,and eventual relocalization prior to the macroscopic failure of the sample.The transient strain rate decay during the stress relaxation phase was quantified using the p-value in the“Omori-like"power law function.A higher initial stress at the onset of relaxation results in a lower p-value,indicating a slower strain rate decay.As the sample approaches macroscopic failure,the lowest p-value shifts from the most damaged zone to adjacent areas,suggesting stress redistribution or crack propagation in deformed crystalline rocks under stress relaxation conditions. 展开更多
关键词 Distributed optical fiber sensing Stress relaxation Strain localization Time-dependent deformation
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Tea polyphenol polymer film enables broadband optical modulation for hybrid mode-locked ultrafast fiber lasers
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作者 Wei Chen Kang Li +4 位作者 Cheng Gao Qingping Hu Zhengfan Li Yi Xiong Yunzhou Sun 《Chinese Physics B》 2026年第2期442-450,共9页
Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In th... Materials exhibiting broadband nonlinear optical responses are critically important for ultrafast photonics applications,particularly as saturable absorbers(SAs)that facilitate broadband optical pulse generation.In this study,tea polyphenolpolyvinyl alcohol(TP-PVA)composite films are synthesized via a polymer embedding method and employed as SAs to initiate ultrafast pulse operation in fiber lasers.The TP-PVA SA film exhibits excellent broadband saturable absorption performance at wavelengths of 1.0μm,1.5μm,and 2.0μm,with modulation depths of 54.21%,41.41%,and 51.16%,respectively.Stable passively mode-locked pulses with pulse widths of 588 fs,419 fs,and 743 fs are generated in Yb-,Er-,and Tm-doped fiber lasers,respectively.This work confirms the effective performance of TP-PVA as a broadband SA,and establishes a foundation for the integration of novel and sustainable materials within ultrafast photonic systems.The approach paves the way for developing compact broadband ultrafast laser systems operating in the near-infrared spectral region. 展开更多
关键词 ultrafast fiber lasers saturable absorbers broadband modulators natural dyes tea polyphenol
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Adversarial robustness evaluation based on classification confidence-based confusion matrix
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作者 YAO Xuemei SUN Jianbin +1 位作者 LI Zituo YANG Kewei 《Journal of Systems Engineering and Electronics》 2026年第1期184-196,共13页
Evaluating the adversarial robustness of classification algorithms in machine learning is a crucial domain.However,current methods lack measurable and interpretable metrics.To address this issue,this paper introduces ... Evaluating the adversarial robustness of classification algorithms in machine learning is a crucial domain.However,current methods lack measurable and interpretable metrics.To address this issue,this paper introduces a visual evaluation index named confidence centroid skewing quadrilateral,which is based on a classification confidence-based confusion matrix,offering a quantitative and visual comparison of the adversarial robustness among different classification algorithms,and enhances intuitiveness and interpretability of attack impacts.We first conduct a validity test and sensitive analysis of the method.Then,prove its effectiveness through the experiments of five classification algorithms including artificial neural network(ANN),logistic regression(LR),support vector machine(SVM),convolutional neural network(CNN)and transformer against three adversarial attacks such as fast gradient sign method(FGSM),DeepFool,and projected gradient descent(PGD)attack. 展开更多
关键词 adversarial robustness evaluation visual evaluation classification confidence-based confusion matrix centroid SKEWING
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