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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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Chaotic dynamics of Pr^(3+)/Yb^(3+)-doped all-fiber up-conversion visible fiber laser
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作者 Yisong Li Yueling Hao +4 位作者 Juanfen Wang Xiaohui Chen Shengxiang Chen Chao Zhou Lingzhen Yang 《Chinese Physics B》 2026年第1期492-496,共5页
We investigate theoretically and experimentally the chaotic dynamics of visible-wavelength all-fiber ring laser.The100-m 630 HP fibers are used to ensure high non-linearity.A 4-m Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber p... We investigate theoretically and experimentally the chaotic dynamics of visible-wavelength all-fiber ring laser.The100-m 630 HP fibers are used to ensure high non-linearity.A 4-m Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber provides the gain.The chaotic laser was pumped by the laser diodes with the maximum power of 150 mW at the wavelength of 850 nm.The peak fluorescence spectrum of Pr^(3+)/Yb^(3+)-co-doped ZBLAN fiber at the wavelength of 635 nm shows that the visiblewavelength fiber laser can be achieved by synergistic energy transfer between Pr~(3+)and Yb^(3+)ions.The chaotic fiber laser is generated by adjusting the pump power,polarization controller and the auto-correlation,permutation entropy,skewness,and kurtosis were used to analyze the characteristics of chaotic laser.The noise-like time series and delta-like auto-correlation curve indicate the chaotic output.The complexity and randomness of time series are analyzed by the permutation entropy,skewness,and kurtosis.The result shows that chaotic dynamics is stable when the pump power exceeds a certain value.The visible chaotic all-fiber laser has high stability and can be applied for real-time monitoring and sensing.We believe that this approach may also be feasible for other materials for emission in the visible range. 展开更多
关键词 chaotic lasers visible fiber laser randomness Pr^(3+)/Yb^(3+)doped fiber
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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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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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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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Copper Fiber Reinforced Alkali-activated Slag Composite Friction Materials by Hot-pressing Method
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作者 ZHAO Zhe XU Lixin +3 位作者 YANG Jiale SI Jiahui ZHU Song JIANG Changjun 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期381-390,共10页
As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-... As the speeds of trains increase,higher demands are placed on brake materials.In order to overcome the thermal degradation phenomenon of brake pads during high-speed braking,we prepared copper fiber reinforced alkali-activated slag composite(AASC)friction materials by hot-pressing method,using slag as matrix,Na_(2)SiO_(3)·9H_(2)O as alkali excitant,copper fiber as reinforcement,and graphite as friction modifier.The results show that the AASC prepared by hot-pressing method has undergone alkali-activated reaction and has geopolymer amorphous characteristics as the conventional cast molding AASC by XRD analysis.The addition of copper fibers can improve the mechanical strength and toughness of the composites substantially,and the AASC has the highest flexural strength,compressive strength and impact toughness when the volume fraction of copper fibers reaches 25 vol%.Toughening mechanisms such as drawing,bridging and crack deflection of copper fibers in composites were analyzed by SEM morphology.Addition of appropriate amount of graphite to AASC can effectively reduce the wear rate and improve the stability of the material friction coefficient.The coefficient of friction also remains stable in the high-speed friction experiments without thermal degradation.Therefore,copper fiber reinforced AASC friction materials prepared by hot-pressing method has good mechanical and friction properties. 展开更多
关键词 HOT-PRESSING alkali-activated slag copper fiber mechanical properties tribological performance
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Development of a“Golden fiber”cotton germplasm via carotenoid biofortification
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作者 Yujie Wang Lu Long +9 位作者 Yanqi Zhang Kaixuan Wang Luying Shao Yingchao Tang Kun Li Wei Gao Jinggong Guo Salim Al-Babili Yuchen Miao Kun-Peng Jia 《The Crop Journal》 2026年第1期285-288,共4页
Natural colored cotton(NCC)offers a sustainable,dye-free,and eco-friendly alternative for producing colored textiles.Carotenoids,a group of important natural liposoluble pigments,are known for their diverse color spec... Natural colored cotton(NCC)offers a sustainable,dye-free,and eco-friendly alternative for producing colored textiles.Carotenoids,a group of important natural liposoluble pigments,are known for their diverse color spectrum.In this study,we successfully engineered the carotenoid biosynthesis pathway specifically in cotton fibers by utilizing a fiber-specific GbEXPA2 promoter and a CaMV 35S promoter to drive the expression of two key carotenoid biosynthesis genes,CrtB and CrtI,respectively.This approach resulted in the development of a golden fiber cotton germplasm enriched withβ-carotene.Notably,the pigmentation was predominantly observed during the early developmental stages of the fiber(5–20 d post-anthesis).While the presence of carotenoids had no significant effect on plant architecture and growth,it positively influenced the fiber elongation rate,albeit with a slight reduction in fiber length and strength.This study represents a pioneering strategy for the future development of NCCs through carotenoid biofortification. 展开更多
关键词 Colored cotton Carotenoid biofortification Golden fiber Β-CAROTENE
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Study of the biological fermentation modification of okara dietary fiber on the regulation on gut microbiota and lipid metabolism in hyperlipidemic mice
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作者 Yaqiong Wan Zhengyang Cheng +7 位作者 Nourhan Nassar Jieping Zhang Meifang Hu Xiaohan Zhou Dongqi Li Yibin Zhou Yayuan Xu Jianghua Cheng 《Food Science and Human Wellness》 2026年第1期395-411,共17页
Okara is produced in large quantities annually in China,but much of it is discarded due to its high content of indigestible dietary fiber(DF),contributing to significant environmental challenges.Recognizing the undere... Okara is produced in large quantities annually in China,but much of it is discarded due to its high content of indigestible dietary fiber(DF),contributing to significant environmental challenges.Recognizing the underexplored medicinal potential of DF,we developed an efficient fermentation method to enhance the bioavailability of okara fiber.In this study,Pediococcus acidilactici IFJ-1,which has strong enzymatic production capabilities and beneficial effects on gastrointestinal flora modulation,was selected to ferment okara.Results showed decreases in viscosity and particle size,optimized surface structure,improved thermal stability and hydration properties,and a significant increase in soluble DF content from 1.85%to 3.91%.To evaluate the physiological effects,hyperlipidemic mouse models were established and subjected to dietary interventions utilizing okara and fermented okara to measure changes in physicochemical parameters,gut microbiota composition,and lipid metabolism.The dietary intervention was effective,particularly in the fermented okara group,showing a 7.3%weight loss,improved blood lipids(triglycerides:‒39.8%,total cholesterol:‒12.8%,low-density lipoprotein cholesterol:‒34.2%,high-density lipoprotein cholesterol:+26.2%),and a 22.2%lower liver index.Gut microbiota analysis revealed that fermented okara positively modulated the microbial community by increasing the abundance of beneficial bacteria(e.g.,Bacteroidota)and reducing the abundance of obesity-associated bacteria(e.g.,Bacillota).Lipid metabolism profiling further demonstrated that fermented okara downregulated harmful lipids(e.g.,(O-acyl)-ω-hydroxy fatty acids,ceramides,and diacylglycerols)while upregulating beneficial phospholipids(e.g.,phosphatidylinositol,phosphatidylserine,phosphatidylethanolamine,lysophosphatidylinositol and lysophosphatidic acid).This study highlights a novel approach for enhancing DF utilization through fermentation,providing valuable insights into strategies for preventing obesity and metabolic diseases. 展开更多
关键词 OKARA Dietary fiber FERMENTATION Pediococcus acidilactici IFJ-1 Gut microbiota Lipid metabolism
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A fungal insoluble fiber from Antrodia camphorata modulates Ruminococcaceae and Helicobacter to restore lipid homeostasis via glycerophospholipid metabolism in HFD mice
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作者 Xin Song Hui Li +8 位作者 Peng Meng Guangqiang Wang Fan Xie Zhiqiang Xiong Yijin Yang Hui Zhang Tingting Shen Yongjun Xia Lianzhong Ai 《Food Science and Human Wellness》 2026年第2期908-923,共16页
High-fat diets(HFD)disrupt lipid homeostasis,posing major public health risks.This study investigated the effect of ACA-DK,an insoluble dietary fiber derived from Antrodia camphorata,on HFD-induced dyslipidemia.We dem... High-fat diets(HFD)disrupt lipid homeostasis,posing major public health risks.This study investigated the effect of ACA-DK,an insoluble dietary fiber derived from Antrodia camphorata,on HFD-induced dyslipidemia.We demonstrate that ACA-DK effectively alleviates HFD-induced dyslipidemia in mice,counteracting metabolic disorders,aberrant blood lipids,and weight gain.Mechanistically,ACA-DK modulates triglycerides,phosphatidylcholine,and phosphatidylethanolamine via glycerophospholipid/choline/linoleic acid metabolism pathways,while rectifying gut dysbiosis through selective reduction of pro-inflammatory genera(Oscillibacter,Ruminiclostridium,Negativibacillus,Ruminococcaceae and Helicobacter).Integrated analysis identifies Ruminococcaceae and Helicobacter as key mediators of ACA-DK's lipid-regulatory effects,establishing microbiota-directed therapy as a strategy against dyslipidemia.We thus propose ACA-DK as a microbiota-directed dual-target therapy,simultaneously reprogramming host lipid metabolism and gut ecology to combat diet-induced metabolic diseases.These findings suggest that ACA-DK is a promising prebiotic dietary fiber for ameliorating HFD-induced lipid metabolic disorders,with potential for future development into functional foods or supplements. 展开更多
关键词 Antrodia camphorata High-fat diet Insoluble dietary fiber Ruminococcaceae Lipid metabolic disorders
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Generation of ultra-flat broad spectrum with stable single-pulse mode-locking in double-clad Yb-doped fiber laser
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作者 Minghui Sun Dongxin Gao +4 位作者 Yunli Yu Wenyu Wang Qingcao Liu Weixin Liu Yuzhai Pan 《Chinese Physics B》 2026年第1期474-480,共7页
We achieved an ultra-flat broad spectrum output with a 20-dB bandwidth of 77.85 nm in a double-clad Yb-doped fiber laser.The intensity difference between the highest and lowest points of the spectrum indicates a flatn... We achieved an ultra-flat broad spectrum output with a 20-dB bandwidth of 77.85 nm in a double-clad Yb-doped fiber laser.The intensity difference between the highest and lowest points of the spectrum indicates a flatness better than4 dB.More notably,this ultra-flat broad spectrum maintains a stable single-pulse mode-locking state.With the increase of pump power,an ultra-wide spectrum with a 20-dB bandwidth approaching 100 nm was formed at a pump power of 2.25 W.Additionally,we obtained a 9-pulse mode-locked state at another PC station with the same pump,which is the highest number of stable mode-locked pulse bursts observed so far with a first-order Raman frequency shift.This fiber laser shows its benefits of ultra-flat broad spectrum,high stability,and ease of fabrication,which provides a new method of obtaining the broadband light source for multiple practical applications. 展开更多
关键词 ultra-flat broad spectrum high stability double-clad Yb-doped fiber mode-locked multi-pulse bursts
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Characterization of ultrahigh-strain-rate compressive behaviors in single 10-μm scale fibers using a micro-scale Hopkinson bar method
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作者 Liang Ma Lingxin Hu +9 位作者 Haoxiang Wang Yichao Yuan Jian Wei Xiaoxin Zhao Kunkun Zeng Yuze Zhao Zhiyin Zhao Jiagui Liu Shizhao Chen Jinling Gao 《Defence Technology(防务技术)》 2026年第2期270-281,共12页
High-performance fiber fabrics and composites experienced transverse compression deformation at ultrahigh strain rates near the impact point when subjected to high-velocity impacts,which significantly affected their b... High-performance fiber fabrics and composites experienced transverse compression deformation at ultrahigh strain rates near the impact point when subjected to high-velocity impacts,which significantly affected their ballistic limits.In this paper,a fiber-scale experimental method for characterizing ultrahigh strain-rate transverse compression behavior was proposed.To begin with,in order to measure the extremely low stress and strain in small specimens,the conventional Hopkinson bar was reduced to the hundred-micron scale,thereby achieving wave impedance matching with single fibers.In addition,tangential and normal laser Doppler velocimetry(LDV)methods were employed to realize non-contact,high-precision,and high-speed axial velocity measurements of micron-scale incident and transmission bars,respectively.Meanwhile,a microscopic observation system was used to facilitate the installation of miniature fiber samples.The experimental setup and procedures were introduced,and the system accuracy was verified through sample-free loading tests based on one-dimensional stress wave propagation theory.Dynamic compression experiments on Graphene-UHMWPE fibers were carried out,followed by post-compression microstructural characterization via scanning electron microscopy(SEM).Results demonstrated that successful mechanical characterization was achieved at strain rates exceeding 105,an order of magnitude higher than the previously reported maximum rates.Furthermore,during the loading process,the fibers underwent uniform compression deformation while exhibiting pronounced strain-rate effects.This method offers a novel approach for dynamic mechanical characterization of microscale single fibers,enabling the development of comprehensive strain-ratedependent material models to guide the design of advanced composites and high-performance fibers. 展开更多
关键词 Single fiber Transverse compression Ultrahigh strain rate Microscale Hopkinson bar Laser Doppler velocimetry
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Thermally Drawn Flexible Fiber Sensors:Principles,Materials,Structures,and Applications
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作者 ZhaoLun Zhang Yuchang Xue +7 位作者 Pengyu Zhang Xiao Yang Xishun Wang Chunyang Wang Haisheng Chen Xinghua Zheng Xin Yin Ting Zhang 《Nano-Micro Letters》 2026年第1期95-129,共35页
Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexib... Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed. 展开更多
关键词 Thermally drawn fiber sensors Sensing principles Temperature sensors Mechanical sensors Multifunctional sensors
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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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Optimized fiber allocation for enhanced impact resistance in composites through damage mode suppression
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作者 Noha M.Hassan Zied Bahroun +2 位作者 Mahmoud I.Awad Rami As'ad El-Cheikh Amer Kaiss 《Defence Technology(防务技术)》 2026年第1期316-329,共14页
Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise,thereby adjusting the panel's stiffness.Since each layer of the composite may... Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise,thereby adjusting the panel's stiffness.Since each layer of the composite may be affected by a different failure mode,the optimal fiber volume fraction to suppress damage initiation and evolution is different across the layers.This research examines how re-allocating the fibers layer-wise enhances the composites'impact resistance.In this study,constant stiffness panels with the same fiber volume fraction throughout the layers are compared to variable stiffness ones by varying volume fraction layer-wise.A method is established that utilizes numerical analysis coupled with optimization techniques to determine the optimal fiber volume fraction in both scenarios.Three different reinforcement fibers(Kevlar,carbon,and glass)embedded in epoxy resin were studied.Panels were manufactured and tested under various loading conditions to validate results.Kevlar reinforcement revealed the highest tensile toughness,followed by carbon and then glass fibers.Varying reinforcement volume fraction significantly influences failure modes.Higher fractions lead to matrix cracking and debonding,while lower fractions result in more fiber breakage.The optimal volume fraction for maximizing fiber breakage energy is around 45%,whereas it is about 90%for matrix cracking and debonding.A drop tower test was used to examine the composite structure's behavior under lowvelocity impact,confirming the superiority of Kevlar-reinforced composites with variable stiffness.Conversely,glass-reinforced composites with constant stiffness revealed the lowest performance with the highest deflection.Across all reinforcement materials,the variable stiffness structure consistently outperformed its constant stiffness counterpart. 展开更多
关键词 Sandwich panel fiber reinforced plastic composites Finite element analysis Variable stiffness Impact resistance Regression analysis Process optimization
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Dislocation Propagation and Mechanical Properties in Poly(p-phenylene terephthalamide) Fibers: An All-atom Molecular Dynamics Simulation
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作者 Jia Wan Ran Chen +1 位作者 Chuan-Fu Luo Xiao-Niu Yang 《Chinese Journal of Polymer Science》 2026年第2期549-559,I0017,共12页
This study uses all-atom molecular dynamics simulations to investigate the dislocation propagation, stress transmission, and mechanical properties in poly(p-phenylene terephthalamide) fibers under uniaxial tension. Th... This study uses all-atom molecular dynamics simulations to investigate the dislocation propagation, stress transmission, and mechanical properties in poly(p-phenylene terephthalamide) fibers under uniaxial tension. The results indicate that the dislocation propagates and the stress transfers not only along the fiber axis but also between adjacent molecular chains through hydrogen bonds, demonstrating their influence on the yield behavior. As the degree of polymerization increases, breakage of covalent bonds and interchain slippage contribute to the yield of fibers together. This work provides theoretical guidance for the design and manufacturing of high-performance fibers. 展开更多
关键词 Molecular dynamic simulation Poly(p-phenylene terephthalamide)fiber Mechanical property Hydrogen bond
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Boosting the adsorption performance of ethanol on surface chemistry modified activated carbon fiber
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作者 Mengyan Wang Yuxuan Wang +6 位作者 Junhao Wang Yinghui Han Jianxiao Yang Suchan Yang Yuanxun Zhang Peng Huo Xin Zhang 《Journal of Environmental Sciences》 2026年第1期178-186,共9页
As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This stud... As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption. 展开更多
关键词 Activated carbon fiber(ACF) Heteroatom doping Surface polarity-modified Polar functional groups Microporous filling Linear driving force(LDF) In-particle diffusion(IPD)
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ZFJ Textile Machinery:High-performance fibers,green fibers,and intelligent equipment
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《China Textile》 2025年第5期66-66,共1页
ZFJ Textile Machinery Co.,Ltd.,established in 1949,is a key enterprise directly managed by China Hi-Tech Group Corporation and falls under the jurisdiction of China National Machinery Industry Corporation Limited(Sino... ZFJ Textile Machinery Co.,Ltd.,established in 1949,is a key enterprise directly managed by China Hi-Tech Group Corporation and falls under the jurisdiction of China National Machinery Industry Corporation Limited(Sinomach).As a leading enterprise in the textile machinery manufacturing industry,ZFJ is dedicated to providing global customers with complete equipment solutions covering the entire industry chain.During this exhibition,ZFJ primarily highlights three key features:"high-performance fibers,green fibers,and intelligent equipment,"with a focus on showcasing nine types of products,spanning various textile equipment categories,including chemical fiber,specialty fiber,nonwoven,sizing,and dyeing machinery. 展开更多
关键词 intelligent equipment NONWOVEN green fibers textile machinery chemical fiber high performance fibers equipment solutions specialty fiber
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Uster Technologies introduces its new fiber process control system
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《China Textile》 2025年第3期48-49,共2页
Fiber quality measurement in spinning preparation is crucial for optimizing waste and meeting yarn quality specifications.The brand-new Uster AFIS 6–the next-generation laboratory instrument from Uster Technologies–... Fiber quality measurement in spinning preparation is crucial for optimizing waste and meeting yarn quality specifications.The brand-new Uster AFIS 6–the next-generation laboratory instrument from Uster Technologies–uniquely tests man-made fiber properties in addition to cotton.It provides critical data to optimize fiber process control for cotton,man-made fibers,and blended yarns. 展开更多
关键词 optimizing waste fiber quality measurement spinning preparation man made fiber blended yarns fiber process control optimize fiber process control
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Fiber optic high temperature sensor with weak strain sensitivity based on Mach-Zehnder interferometric structure
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作者 LIU Ming MA Chengju +3 位作者 ZHANG Yixin LIU Qianzhen HU Hui WU Jirui 《Optoelectronics Letters》 2025年第4期199-204,共6页
We proposed a fiber optic high temperature sensor based on the Mach-Zehnder interference(MZI)structure,which is composed of two lengths of multi-mode fibers(MMFs),a length of few-mode fiber(FMF)and two sections of sin... We proposed a fiber optic high temperature sensor based on the Mach-Zehnder interference(MZI)structure,which is composed of two lengths of multi-mode fibers(MMFs),a length of few-mode fiber(FMF)and two sections of single-mode fibers(SMFs).Firstly,the two sections of MMFs were spliced with two sections of SMFs.Then,the MMFs were fused to two ends of FMF to form a symmetrically structured fiber-optic MZI structure.In this structure,the MMF served as the optical mode field coupling element,and the cladding and core of the FMF are the interference arm and the reference arm of the MZI structure,respectively.We investigated the sensor's response characteristics of the temperature and strain.The experimental results indicate that the sensor is sensitive to temperature variation,and the temperature response sensitivity is up to 61.4 pm/℃ in the range of 40-250℃,while the sensor has weak strain sensitivity,its strain sensitivity is only-0.72 pm/μe in the strain range of 0-1400μe.Moreover,the sensor has good stability and repeatability.In brief,the proposed fiber optic high temperature sensor has good properties,such as high sensitivity,compact structure,good stability and repeatability,which can be used for monitoring the temperature of submerged oil electric pump units under oil wells. 展开更多
关键词 fiber optic sensor weak strain sensitivity optical mode field coupling elementand multi mode fiber Mach Zehnder interferometric structure temperature sensing single mode fiber few mode fiber
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