The absolute frequency of 87Rb 5S1/2 （F=2）→5D5/2 （F＂ = 4） two-photon transition at 778nm is measured in an accuracy of 44kHz. A home-made erbium-doped fiber laser frequency comb with frequency stability of 5.0 ...The absolute frequency of 87Rb 5S1/2 （F=2）→5D5/2 （F＂ = 4） two-photon transition at 778nm is measured in an accuracy of 44kHz. A home-made erbium-doped fiber laser frequency comb with frequency stability of 5.0 × 10-13@1 s is employed for the light source. By using a periodically poled lithium niobate, the femtosecond pulse operating in 1556 nm is frequency-doubled to 778 nm to obtain the direct two-photon transition spectroscopy of thermal rubidium vapor. Through sweeping the carrier envelope offset frequency （fceo）, the 5S1/2 （F=2）→5D5/2 （F＂ = 4） two-photon transition line is clearly resolved and its absolute frequency is determined via the peak-finding of the fitting curve. After the frequency correction, the measured result agrees well with the previous experiment on this transition. The entire potential candidate of optical frequency standard for system configuration is compact and robust, providing a telecommunication applications.展开更多
A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase microextxaodon （LPME） based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electr...A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase microextxaodon （LPME） based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electrokinodc chromatography was developed. The calibration curve was linear over the range of 20-200 ng mL^-1 for both strychnine and brucine in human urine sample. The detection limits （S/N = 3：1） for strychnine and brucine were 1 ng mL^-1 and 2 ng mL^-1, respectively. The LPME-sweeping method has been successfully applied to the analysis of strychnine and brucine in real urine samples.展开更多
Highly stable frequency-controlled optical frequency combs axe key elements of many applications in time- frequency and optical-metrology domains. In this work, we demonstrate a highly stable frequency-controlled erbi...Highly stable frequency-controlled optical frequency combs axe key elements of many applications in time- frequency and optical-metrology domains. In this work, we demonstrate a highly stable frequency-controlled erbium-fiber-based optical frequency comb system. Its repetition rate is phase-stabilized to a continuous-wave laser with both an intra-cavity electro-optic modulator and a piezo-transducer; while the carrier-envelope-offset frequency is phase-locked to a radio-frequency signal generator by controlling the pump power. In-loop relative frequency stabilities of the comb are below 1 ×10-16 at I s, and integrate down to low 10-2o level at 104 s. The corresponding timing uncertainties are 100-200 as over the full measurement range.展开更多
The acute pain induced by clinical procedures,such as venipuncture,dental operations,and dermatological treatments,as well as postoperative pain,drives the advancement of anesthetic techniques aimed at alleviating dis...The acute pain induced by clinical procedures,such as venipuncture,dental operations,and dermatological treatments,as well as postoperative pain,drives the advancement of anesthetic techniques aimed at alleviating discomfort.This situation under-scores the ongoing significance of effective pain management strategies within the field of anesthesia.This paper presents an integrated iontophoresis(ITP)-driven fiber-based microneedle patch(IFMP)regulated by a smartphone for controllable,long-lasting lidocaine transdermal delivery.The IFMP integrates pure cotton fiber canvas-based dissolving microneedles(MNs)with ITP into a patch,with the MNs tips and gel layers significantly increasing the drug-loading capacity,achieving a one-step drug administration strategy of“dissolution,diffusion,and ITP.”Lidocaine is released via the microchannels of MNs by passive diffusion.Additionally,an electric current initiates active ITP for lidocaine delivery,creating synergy.User-requirement-based drug release by precisely modulating electrical signals in rat pain models is described herein.A smartphone application enables precise dosage control.It offers three different delivery modes:single-dose,pulse delivery,and sustained-release,ensuring rapid onset,and long-lasting pain relief.This versatility makes the system suitable for various pain conditions.The IFMP represents a promising system for patient-controlled local analgesia treatment,enabling active and long-term local self-controlled pain management in a safe and regulated manner.展开更多
Wearable electronics on fibers or fabrics assembled with electronic functions provide a platform for sensors,displays,circuitry,and computation.These new conceptual devices are human-friendly and programmable,which ma...Wearable electronics on fibers or fabrics assembled with electronic functions provide a platform for sensors,displays,circuitry,and computation.These new conceptual devices are human-friendly and programmable,which makes them indis-pensable for modern electronics.Their unique properties such as being adaptable in daily life,as well as being lightweight and flexible,have enabled many promising applications in robotics,healthcare,and the Internet of Things(IoT).Transistors,one of the fundamental blocks in electronic systems,allow for signal processing and computing.Therefore,study leading to integration of transistors with fabrics has become intensive.Here,several aspects of fiber-based transistors are addressed,including materials,system structures,and their functional devices such as sensory,logical circuitry,memory devices as well as neuromorphic computation.Recently reported advances in development and challenges to realizing fully integrated electronic textile(e-textile)systems are also discussed.展开更多
Twisted and coiled fiber-based actuators have drawn a great attention because their unique structure can provide mechanical response with the external thermal stimulus.Herein,an ultra-fast and light-weight twisted and...Twisted and coiled fiber-based actuators have drawn a great attention because their unique structure can provide mechanical response with the external thermal stimulus.Herein,an ultra-fast and light-weight twisted and coiled fiber-based actuator was designed based on a nature melanin/poly(vinyl alcohol-co-ethylene)(PVA-co-PE)nanofibers/PA6 composite fiber.In brief,PA6 was firstly coated by melanin/PVA-co-PE nanofibers using a spraying method,followed by the twisting and coat-ing the composite fiber to obtain the actuator.The excellent photothermal property of melanin contributed to the superior performance of the actuator,whereas the PVA-co-PE nanofibers was responsible for the uniform distribution of melanin and the enhanced mechanical property of the prepared-actuator.This unique design has led to the high performance of the melanin/NFs/PA6 fiber-based actuator,whose torsion actuation can reach to 14,000 rpm,and maximum tensile actuation was−6.36%at temperature difference of 40℃.In addition,the tensile stress of PA6/NFs/melanin fiber was about four times higher than PA6 filaments.Owing to the simple and environmental-benign preparation method,as well as the excellent effi-ciency of twisted and coiled melanin/NFs/PA6 fiber-based actuator,this study highlights the facile design of the composite fiber for high-performance fiber-based actuators.This fiber-based actuator is promising for application in energy generator.展开更多
A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented.The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach–Zehnder interferome...A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented.The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach–Zehnder interferometer at room temperature.A polarization controller is further utilized to enable switchable dualwavelength operation.展开更多
The trends of fiber-based optical component technologies are reviewed focusing on fused-taper couplers and fiber Bragg gratings for high bit-rate DWDM transmission systems.
We have investigated the transient characteristics of discrete Raman Amplifiers and found that the response time caused by gain saturation is dependent upon the wavelength, which corresponds to the effective length of...We have investigated the transient characteristics of discrete Raman Amplifiers and found that the response time caused by gain saturation is dependent upon the wavelength, which corresponds to the effective length of the pump light.展开更多
In this letter, we investigate quasi-cyclic low-density parity-check （QC-LDPC） codes in a 40-Gb/s nonreturn-to-zero differential phase-shift keying （NRZ-DPSK） signal transmission system based on a fiber- based opt...In this letter, we investigate quasi-cyclic low-density parity-check （QC-LDPC） codes in a 40-Gb/s nonreturn-to-zero differential phase-shift keying （NRZ-DPSK） signal transmission system based on a fiber- based optical parametric amplifier （FOPA）. A constructed algorithm of QC-LDPC codes according to the optimizing set of shift vMues on the circulant permutation matrix （CPM） of the basis matrix is proposed. Simulation results prove that the coding gain in the encoded system can be realized at 10.2 dB under QC- LDPC codes with a code rate of 5/6 when the bit error rate （BER） is 10-9. In addition, the error-floor level originating from the uncoded system is suppressed.展开更多
Carbon fiber reinforced polyamide 12(CF/PA12),a new material renowned for its excellent mechanical and thermal properties,has drawn significant industry attention.Using the steady-state research to heat transfer,a ser...Carbon fiber reinforced polyamide 12(CF/PA12),a new material renowned for its excellent mechanical and thermal properties,has drawn significant industry attention.Using the steady-state research to heat transfer,a series of simulations to investigate the heat transfer properties of CF/PA12 were conducted in this study.Firstly,by building two-and three-dimensional models,the effects of the porosity,carbon fiber content,and arrangement on the heat transfer of CF/PA12 were examined.A validation of the simulation model was carried out and the findings were consistent with those of the experiment.Then,the simulation results using the above models showed that within the volume fraction from 0% to 28%,the thermal conductivity of CF/PA12 increased greatly from 0.0242 W/(m·K)to 10.8848 W/(m·K).The increasing porosity had little influence on heat transfer characteristic of CF/PA12.The direction of the carbon fiber arrangement affects the heat transfer impact,and optimal outcomes were achieved when the heat flow direction was parallel to the carbon fiber.This research contributes to improving the production methods and broadening the application scenarios of composite materials.展开更多
Due to their potential use in creating advanced electronic textiles for wearable technology,functional fibers have garnered enormous interests.The presence of stretchable smart fibers has significantly expanded the ap...Due to their potential use in creating advanced electronic textiles for wearable technology,functional fibers have garnered enormous interests.The presence of stretchable smart fibers has significantly expanded the application scenarios of intelligent fibers.However,preparing fibers that possess both excellent electrical performance and high stretchability remains a formidable challenge.The fabrication of stretchable multifunctional fiber-based sensors employing a scalable method is reported here.Using a thermal drawing process,the collaborative interplay between the hollow confined channels of superelastic poly(styrene-b-(ethylene-co-butylene)-b-styrene)(SEBS)thermally drawn fibers and the high fluidity of liquid metal(LM)ensures the exceptional electrical performance of the fibers.Simultaneously,the presence of a helical structure further enhances both the sensing and mechanical properties.The helical two LM channel fiber-based sensors are capable of displaying more than 1000%strain,high stability over 1000 cycles,a quick pressure response and release time of 30.45 and 45.35 ms,and outstanding electrical conductivity of 8.075×10^(5)S/m.In addition,the electrical conductivity of this fiber increases with strain level,reaching 3×10^(6)S/m when the strain is 500%.Furthermore,due to their superior tension and compression sensing capabilities,flexible helical sensors offer considerable potential for use in wearable electronics applications such as human motion detection,Morse code compilation,multichannel sensing,and more.展开更多
To meet the requirements for the mechanical and electrochemical performance for carbon fiber-based (CF-based) composites in the structural lithium ion batteries (SLIBs) application, better CF-Based composites are urge...To meet the requirements for the mechanical and electrochemical performance for carbon fiber-based (CF-based) composites in the structural lithium ion batteries (SLIBs) application, better CF-Based composites are urgently needed. Herein, we report a novel composite metal organic framework (MOF)-derived ZnCo_2 O_4/C@carbon fiber via a facile method and subsequent annealing treatment. In this anode,the nano ZnCo_2 O_4/C coatings wrapped on the surface of CF provide more active sites for electrode reactions and the thin carbon layers give the additional protection. For this material, after 100 cycles, it exhibits excellent cycling stability including high reversible capacity of 463 mAh/g at 50 mA/g, which increases 201% than that of the CF. Thus, this structural anode material exhibits enhanced capacity, high initial columbic efficiency.展开更多
Graphene fiber-based supercapacitors hold great promise as flexible energy-storage devices. However, simultaneously achieving high ion-transport ability in electrode and electrolyte layer, which is crucial for realizi...Graphene fiber-based supercapacitors hold great promise as flexible energy-storage devices. However, simultaneously achieving high ion-transport ability in electrode and electrolyte layer, which is crucial for realizing the high electrochemical performance, still remains challenging. Here, a facile and effective strategy to solve the problem was proposed by developing a twisting-structured graphene/carbon nanotube(CNT) fiber supercapacitor via one-step wet-spinning process with customized multi-channel spinneret.The remarkable structure features of the resulting fiber supercapacitor with wrinkled and thin electrolyte layer, and well-developed porosity of fiber electrode favored the rapid infiltration and transport of electrolyte ions inside the electrode, as well as between electrode and electrolyte, thus boosting high specific capacitance of 187.6 mF cm^(-2) and energy density of 30.2 μWh cm^(-2), and featuring long cycling life(93%capacitance retention after 10,000 cycles) and excellent flexibility. Moreover, the specific capacitance and energy density could be further improved to 267.2 m F cm^(-2) and 66.8 μWh cm^(-2), respectively, when Mn O2 was incorporated into the fiber.展开更多
Owing to its subtropical or tropical environment and climate,South China is home to unique agricultural crops such as sugar cane,pineapple,banana,cassava,and rice,which generate a large amount of lignocellulosic agric...Owing to its subtropical or tropical environment and climate,South China is home to unique agricultural crops such as sugar cane,pineapple,banana,cassava,and rice,which generate a large amount of lignocellulosic agricultural wastes during agricultural as well as associated industrial processing.The efficient utilization of these wastes will have a significant impact on the economy and sustainable development of South China.This paper reviews the research investigations conducted both in China and elsewhere on the conversion of wastes from these subtropical or tropical agricultural crops into useful chemicals,energy,and biomaterials.The goal of this paper is to promote and summarize the extensive investigations on these agricultural wastes for the development of biorefinery.展开更多
To verify the seismic design response factors of high-rise buildings, five reference structures, varying in height from 20- to 60-stories, were selected and designed according to modern design codes to represent a wid...To verify the seismic design response factors of high-rise buildings, five reference structures, varying in height from 20- to 60-stories, were selected and designed according to modern design codes to represent a wide range of concrete wall structures. Verified fiber-based analytical models for inelastic simulation were developed, considering the geometric nonlinearity and material inelasticity of the structural members. The ground motion uncertainty was accounted for by employing 20 earthquake records representing two seismic scenarios, consistent with the latest understanding of the tectonic setting and seismicity of the selected reference region （UAE）. A large number of Inelastic Pushover Analyses （IPAs） and Incremental Dynamic Collapse Analyses （IDCAs） were deployed for the reference structures to estimate the seismic design response factors. It is concluded that the factors adopted by the design code are adequately conservative. The results of this systematic assessment of seismic design response factors apply to a wide variety of contemporary concrete wall buildings with various characteristics.展开更多
In exploring fiber-based materials,the advantages of their inner constructions and displayed wettabilities diversify their applications and especially facilitate the development of immiscible liquid separation.When co...In exploring fiber-based materials,the advantages of their inner constructions and displayed wettabilities diversify their applications and especially facilitate the development of immiscible liquid separation.When considering the basis of their liquid‒phase separation properties,such fibrous materials can be employed in more abundant and novel application fields in addition to oil-water separation.This article reviews the recent progress in the development of fiber-based materials with special surface wettabilities and further explores their potential in immiscible liquid separation-related fields,such as liquid/liquid mass transfer,and explores related applications in environmental purification,resource collection,energy storage and other fields.This article also explores the underlying nature that drives the wetting performance of fibrous surfaces,extends more diversified underliquid wetting models,and fully summarizes the separation mechanism and the latest corresponding applications,opening up an avenue for identifying the significance of devisable wetting performances and developing more diversified application potentials.Finally,this review proposes current challenges and expected developments in superwetting fiber-based materials with immiscible liquid separation abilities.展开更多
The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous poten...The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations.展开更多
Fiber-based microplastics(FMPs)are highly persistent and ubiquitously exist in the wastewater of textile industry and urban sewage.It remains challenging to completely remove such newly emerged organic pollutants by t...Fiber-based microplastics(FMPs)are highly persistent and ubiquitously exist in the wastewater of textile industry and urban sewage.It remains challenging to completely remove such newly emerged organic pollutants by the predominant physical techniques.In this work,we investigated a photocatalytic degradation catalyzed by TiO_(2) catalyst to demonstrate the feasibility of implementing efficient chemical protocol to fast degrading polyethylene terephthalate(PET)-FMPs(a major FMP type existing in environment).The result shows that a hydrothermal pretreatment(180℃/12 h)is necessary to induce the initial rough appearance and molecular weight reduction.With the comprehensive action of the nano-flower shaped N doped-TiO_(2) catalyst(Pt@N-TiO_(2)-1.5%)on the relatively low molecular weight intermediates,an approximate 29%weight loss was induced on the pretreated PET-FMPs,which is about 8 times superior to the untreated sample.This work not only achieves a superior degradation effect of PET-FMPs,but also provides a new inspiration for the proposal of reduction strategies in the field of environmental remediation in the future.展开更多
Wearable fiber-based electronics have found diverse applications including energy storage,healthcare or thermal management,etc.In particular,additive-free aqueous inks play significant roles in fabrication of wearable...Wearable fiber-based electronics have found diverse applications including energy storage,healthcare or thermal management,etc.In particular,additive-free aqueous inks play significant roles in fabrication of wearable fiber-based devices,owning to their nontoxic nature and ease of manufacturing.Herein,wearable carbon fiber-based asymmetric supercapacitors(WASSC)are developed based on additive-free aqueous MXene inks,for self-powering healthcare sensors.The sediments of MXene without further modification are used as inks.Furthermore,combined with additive-free aqueous MXene/polyaniline(MP)inks,WASSC,with a wide voltage window and high capacitance is developed for practical energy supply.Impressively,WASSC has been successfully utilized to power wearable pressure sensors that could monitor motions and pulse signals.This wearable self-powered monitoring system on can accurately monitor the human motions,pronunciation,swallow or wrist pulse,without using the rigid batteries.This advantage realizes a great potential in simple and cost effective monitoring of human health and activities.Besides,self-powered system enables waste recycling of MXene and provides an effective approach for designing wearable and fiber-based self-powered sensors.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61405002,91336103,10934010,61535001 and 61078026
文摘The absolute frequency of 87Rb 5S1/2 （F=2）→5D5/2 （F＂ = 4） two-photon transition at 778nm is measured in an accuracy of 44kHz. A home-made erbium-doped fiber laser frequency comb with frequency stability of 5.0 × 10-13@1 s is employed for the light source. By using a periodically poled lithium niobate, the femtosecond pulse operating in 1556 nm is frequency-doubled to 778 nm to obtain the direct two-photon transition spectroscopy of thermal rubidium vapor. Through sweeping the carrier envelope offset frequency （fceo）, the 5S1/2 （F=2）→5D5/2 （F＂ = 4） two-photon transition line is clearly resolved and its absolute frequency is determined via the peak-finding of the fitting curve. After the frequency correction, the measured result agrees well with the previous experiment on this transition. The entire potential candidate of optical frequency standard for system configuration is compact and robust, providing a telecommunication applications.
基金This work was supported both by the Natural Science Foundation of Hebei Province(B2006000413)the Scientific Research Foundation for the Returned 0verseas Chinese Scholars,State Education Ministry.
文摘A new method for the enrichment of Strychnos alkaloids in biological samples via liquid-phase microextxaodon （LPME） based on porous polypropylene hollow fibers in combination with on-line sweeping in micellar electrokinodc chromatography was developed. The calibration curve was linear over the range of 20-200 ng mL^-1 for both strychnine and brucine in human urine sample. The detection limits （S/N = 3：1） for strychnine and brucine were 1 ng mL^-1 and 2 ng mL^-1, respectively. The LPME-sweeping method has been successfully applied to the analysis of strychnine and brucine in real urine samples.
基金Supported by the National Natural Science Foundation of China under Grant Nos 91336101 and 61127901the West Light Foundation of the Chinese Academy of Sciences under Grant No 2013ZD02
文摘Highly stable frequency-controlled optical frequency combs axe key elements of many applications in time- frequency and optical-metrology domains. In this work, we demonstrate a highly stable frequency-controlled erbium-fiber-based optical frequency comb system. Its repetition rate is phase-stabilized to a continuous-wave laser with both an intra-cavity electro-optic modulator and a piezo-transducer; while the carrier-envelope-offset frequency is phase-locked to a radio-frequency signal generator by controlling the pump power. In-loop relative frequency stabilities of the comb are below 1 ×10-16 at I s, and integrate down to low 10-2o level at 104 s. The corresponding timing uncertainties are 100-200 as over the full measurement range.
基金supported by the Science and Technology Commission of Shanghai Municipality(Grant No.21520710700)Shanghai Municipal Science and Technology Major Project(Grant No.22xtcx00600)+1 种基金Shanghai Municipal Science and Technology Major Project(Grant No.22xtcx00601)the Fundamental Research Funds for the Central Universities(Grant No.223202023G-12).
文摘The acute pain induced by clinical procedures,such as venipuncture,dental operations,and dermatological treatments,as well as postoperative pain,drives the advancement of anesthetic techniques aimed at alleviating discomfort.This situation under-scores the ongoing significance of effective pain management strategies within the field of anesthesia.This paper presents an integrated iontophoresis(ITP)-driven fiber-based microneedle patch(IFMP)regulated by a smartphone for controllable,long-lasting lidocaine transdermal delivery.The IFMP integrates pure cotton fiber canvas-based dissolving microneedles(MNs)with ITP into a patch,with the MNs tips and gel layers significantly increasing the drug-loading capacity,achieving a one-step drug administration strategy of“dissolution,diffusion,and ITP.”Lidocaine is released via the microchannels of MNs by passive diffusion.Additionally,an electric current initiates active ITP for lidocaine delivery,creating synergy.User-requirement-based drug release by precisely modulating electrical signals in rat pain models is described herein.A smartphone application enables precise dosage control.It offers three different delivery modes:single-dose,pulse delivery,and sustained-release,ensuring rapid onset,and long-lasting pain relief.This versatility makes the system suitable for various pain conditions.The IFMP represents a promising system for patient-controlled local analgesia treatment,enabling active and long-term local self-controlled pain management in a safe and regulated manner.
基金This work was supported by the Singapore Ministry of Education Academic Research Fund Tier 2(Nos.MOE2019-T2-2-127 and MOE-T2EP50120-0002),A*STAR under AME IRG(No.A2083c0062)the Singapore Ministry of Education Academic Research Fund Tier 1(Nos.RG90/19 and RG73/19)the Singapore National Research Foundation Competitive Research Program(No.NRF-CRP18-2017-02)。
文摘Wearable electronics on fibers or fabrics assembled with electronic functions provide a platform for sensors,displays,circuitry,and computation.These new conceptual devices are human-friendly and programmable,which makes them indis-pensable for modern electronics.Their unique properties such as being adaptable in daily life,as well as being lightweight and flexible,have enabled many promising applications in robotics,healthcare,and the Internet of Things(IoT).Transistors,one of the fundamental blocks in electronic systems,allow for signal processing and computing.Therefore,study leading to integration of transistors with fabrics has become intensive.Here,several aspects of fiber-based transistors are addressed,including materials,system structures,and their functional devices such as sensory,logical circuitry,memory devices as well as neuromorphic computation.Recently reported advances in development and challenges to realizing fully integrated electronic textile(e-textile)systems are also discussed.
基金The authors acknowledge the National Natural Science Foundation of China(Grant No.51873166,51873165)the Natural Science Foundation of Hubei Province(2016CFB386)+2 种基金Program of Hubei Technology Innovation-International Collaboration(2017AHB065)Applied Fundamental Research Program of Wuhan Science and Technology Bureau(2017060201010165)for financial supportThe authors also acknowledge for the financial support from Wuhan Advanced Fiber Engineering Technology Research Center and the Hubei Province Central Government Guides Local Science and Technology Development Projects(2018ZYYD057).
文摘Twisted and coiled fiber-based actuators have drawn a great attention because their unique structure can provide mechanical response with the external thermal stimulus.Herein,an ultra-fast and light-weight twisted and coiled fiber-based actuator was designed based on a nature melanin/poly(vinyl alcohol-co-ethylene)(PVA-co-PE)nanofibers/PA6 composite fiber.In brief,PA6 was firstly coated by melanin/PVA-co-PE nanofibers using a spraying method,followed by the twisting and coat-ing the composite fiber to obtain the actuator.The excellent photothermal property of melanin contributed to the superior performance of the actuator,whereas the PVA-co-PE nanofibers was responsible for the uniform distribution of melanin and the enhanced mechanical property of the prepared-actuator.This unique design has led to the high performance of the melanin/NFs/PA6 fiber-based actuator,whose torsion actuation can reach to 14,000 rpm,and maximum tensile actuation was−6.36%at temperature difference of 40℃.In addition,the tensile stress of PA6/NFs/melanin fiber was about four times higher than PA6 filaments.Owing to the simple and environmental-benign preparation method,as well as the excellent effi-ciency of twisted and coiled melanin/NFs/PA6 fiber-based actuator,this study highlights the facile design of the composite fiber for high-performance fiber-based actuators.This fiber-based actuator is promising for application in energy generator.
基金Financial support for this work was provided by the Deanship of Scientific Research(DSR)of King Fahd University of Petroleum and Minerals under Grant No.FT121004
文摘A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented.The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach–Zehnder interferometer at room temperature.A polarization controller is further utilized to enable switchable dualwavelength operation.
文摘The trends of fiber-based optical component technologies are reviewed focusing on fused-taper couplers and fiber Bragg gratings for high bit-rate DWDM transmission systems.
文摘We have investigated the transient characteristics of discrete Raman Amplifiers and found that the response time caused by gain saturation is dependent upon the wavelength, which corresponds to the effective length of the pump light.
基金supported by the National Natural Science Foundation of China(No.41174158)the National Commonwealth Research Project of China(No.201011081-4)
文摘In this letter, we investigate quasi-cyclic low-density parity-check （QC-LDPC） codes in a 40-Gb/s nonreturn-to-zero differential phase-shift keying （NRZ-DPSK） signal transmission system based on a fiber- based optical parametric amplifier （FOPA）. A constructed algorithm of QC-LDPC codes according to the optimizing set of shift vMues on the circulant permutation matrix （CPM） of the basis matrix is proposed. Simulation results prove that the coding gain in the encoded system can be realized at 10.2 dB under QC- LDPC codes with a code rate of 5/6 when the bit error rate （BER） is 10-9. In addition, the error-floor level originating from the uncoded system is suppressed.
基金Projects(52206216,52376085)supported by the National Natural Science Foundation of ChinaProject(2023JJ40744)supported by the Natural Science Foundation of Hunan Province,China。
文摘Carbon fiber reinforced polyamide 12(CF/PA12),a new material renowned for its excellent mechanical and thermal properties,has drawn significant industry attention.Using the steady-state research to heat transfer,a series of simulations to investigate the heat transfer properties of CF/PA12 were conducted in this study.Firstly,by building two-and three-dimensional models,the effects of the porosity,carbon fiber content,and arrangement on the heat transfer of CF/PA12 were examined.A validation of the simulation model was carried out and the findings were consistent with those of the experiment.Then,the simulation results using the above models showed that within the volume fraction from 0% to 28%,the thermal conductivity of CF/PA12 increased greatly from 0.0242 W/(m·K)to 10.8848 W/(m·K).The increasing porosity had little influence on heat transfer characteristic of CF/PA12.The direction of the carbon fiber arrangement affects the heat transfer impact,and optimal outcomes were achieved when the heat flow direction was parallel to the carbon fiber.This research contributes to improving the production methods and broadening the application scenarios of composite materials.
基金the National Natural Science Foundation of China(No.52173059)the National Key Research and Development Program of China(No.2022YFB3805803)+1 种基金the Key Research and Development Program of Jiangsu Province(No.21KJA540002)China National Textile and Apparel Council Science and Technology Guidance Project(No.2020116).
文摘Due to their potential use in creating advanced electronic textiles for wearable technology,functional fibers have garnered enormous interests.The presence of stretchable smart fibers has significantly expanded the application scenarios of intelligent fibers.However,preparing fibers that possess both excellent electrical performance and high stretchability remains a formidable challenge.The fabrication of stretchable multifunctional fiber-based sensors employing a scalable method is reported here.Using a thermal drawing process,the collaborative interplay between the hollow confined channels of superelastic poly(styrene-b-(ethylene-co-butylene)-b-styrene)(SEBS)thermally drawn fibers and the high fluidity of liquid metal(LM)ensures the exceptional electrical performance of the fibers.Simultaneously,the presence of a helical structure further enhances both the sensing and mechanical properties.The helical two LM channel fiber-based sensors are capable of displaying more than 1000%strain,high stability over 1000 cycles,a quick pressure response and release time of 30.45 and 45.35 ms,and outstanding electrical conductivity of 8.075×10^(5)S/m.In addition,the electrical conductivity of this fiber increases with strain level,reaching 3×10^(6)S/m when the strain is 500%.Furthermore,due to their superior tension and compression sensing capabilities,flexible helical sensors offer considerable potential for use in wearable electronics applications such as human motion detection,Morse code compilation,multichannel sensing,and more.
文摘To meet the requirements for the mechanical and electrochemical performance for carbon fiber-based (CF-based) composites in the structural lithium ion batteries (SLIBs) application, better CF-Based composites are urgently needed. Herein, we report a novel composite metal organic framework (MOF)-derived ZnCo_2 O_4/C@carbon fiber via a facile method and subsequent annealing treatment. In this anode,the nano ZnCo_2 O_4/C coatings wrapped on the surface of CF provide more active sites for electrode reactions and the thin carbon layers give the additional protection. For this material, after 100 cycles, it exhibits excellent cycling stability including high reversible capacity of 463 mAh/g at 50 mA/g, which increases 201% than that of the CF. Thus, this structural anode material exhibits enhanced capacity, high initial columbic efficiency.
基金financial supports from the National Key Research and Development Program of China (2016YFA0203301)the National Natural Science Foundation of China (U1710122, 51862035, 21773293)+5 种基金the Program for Science & Technology Innovation Talents in the Universities of Henan Province (18HASTIT007)the Natural Science Foundation of Henan Provinceof China (182300410201, 182300410202)Jiangxi Double Thousand Talents Program (Y. Zhang, S2018LQCQ0016)the Science and Technology Project of Jiangxi Province (20181ACH80008, 20181ACE50012)the Key Foundation of He’nan Educational Committee (18A150029)the Fundamental Research Funds for the Universities of Henan Province (NSFRF180337)。
文摘Graphene fiber-based supercapacitors hold great promise as flexible energy-storage devices. However, simultaneously achieving high ion-transport ability in electrode and electrolyte layer, which is crucial for realizing the high electrochemical performance, still remains challenging. Here, a facile and effective strategy to solve the problem was proposed by developing a twisting-structured graphene/carbon nanotube(CNT) fiber supercapacitor via one-step wet-spinning process with customized multi-channel spinneret.The remarkable structure features of the resulting fiber supercapacitor with wrinkled and thin electrolyte layer, and well-developed porosity of fiber electrode favored the rapid infiltration and transport of electrolyte ions inside the electrode, as well as between electrode and electrolyte, thus boosting high specific capacitance of 187.6 mF cm^(-2) and energy density of 30.2 μWh cm^(-2), and featuring long cycling life(93%capacitance retention after 10,000 cycles) and excellent flexibility. Moreover, the specific capacitance and energy density could be further improved to 267.2 m F cm^(-2) and 66.8 μWh cm^(-2), respectively, when Mn O2 was incorporated into the fiber.
基金support from China Postdoctoral Science Foundation(2016M590783)the Foundation of Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education of China(KF2015013)
文摘Owing to its subtropical or tropical environment and climate,South China is home to unique agricultural crops such as sugar cane,pineapple,banana,cassava,and rice,which generate a large amount of lignocellulosic agricultural wastes during agricultural as well as associated industrial processing.The efficient utilization of these wastes will have a significant impact on the economy and sustainable development of South China.This paper reviews the research investigations conducted both in China and elsewhere on the conversion of wastes from these subtropical or tropical agricultural crops into useful chemicals,energy,and biomaterials.The goal of this paper is to promote and summarize the extensive investigations on these agricultural wastes for the development of biorefinery.
基金UAE University Under Contracts No. 07-34-07-11/07 and 07-01-07-11/09
文摘To verify the seismic design response factors of high-rise buildings, five reference structures, varying in height from 20- to 60-stories, were selected and designed according to modern design codes to represent a wide range of concrete wall structures. Verified fiber-based analytical models for inelastic simulation were developed, considering the geometric nonlinearity and material inelasticity of the structural members. The ground motion uncertainty was accounted for by employing 20 earthquake records representing two seismic scenarios, consistent with the latest understanding of the tectonic setting and seismicity of the selected reference region （UAE）. A large number of Inelastic Pushover Analyses （IPAs） and Incremental Dynamic Collapse Analyses （IDCAs） were deployed for the reference structures to estimate the seismic design response factors. It is concluded that the factors adopted by the design code are adequately conservative. The results of this systematic assessment of seismic design response factors apply to a wide variety of contemporary concrete wall buildings with various characteristics.
基金the National Key Research and Development Program of China(Grant 2021YFA1501202,2022YFA1503600)the National Natural Science Foundation of China(Grant 22288101,21920102005)+3 种基金the‘111 Center’(B17020)the Natural Science Foundation of Jilin Province(SKL202402008)the China Postdoctoral Science Foundation(2023M731272)the Postdoctoral Fellowship Program of CPSF(GZB20230254)for supporting this work.
文摘In exploring fiber-based materials,the advantages of their inner constructions and displayed wettabilities diversify their applications and especially facilitate the development of immiscible liquid separation.When considering the basis of their liquid‒phase separation properties,such fibrous materials can be employed in more abundant and novel application fields in addition to oil-water separation.This article reviews the recent progress in the development of fiber-based materials with special surface wettabilities and further explores their potential in immiscible liquid separation-related fields,such as liquid/liquid mass transfer,and explores related applications in environmental purification,resource collection,energy storage and other fields.This article also explores the underlying nature that drives the wetting performance of fibrous surfaces,extends more diversified underliquid wetting models,and fully summarizes the separation mechanism and the latest corresponding applications,opening up an avenue for identifying the significance of devisable wetting performances and developing more diversified application potentials.Finally,this review proposes current challenges and expected developments in superwetting fiber-based materials with immiscible liquid separation abilities.
基金supported by the National Natural Science Foundation of China(No.62035015,No.61805280,No.62061136013)Innovation Group of Hunan Province,China(No.2019JJ10005)+1 种基金Hunan Innovative Province Construction Project,China(No.2019RS3017)the Research Plan of National University of Defense Technology(No.ZK19-07).
文摘The success of high-power fiber lasers is fueled by maturation of active and passive fibers,combined with the availability of high-power fiber-based components.In this contribution,we first overview the enormous potential of rare-earth doped fibers in spectral coverage and recent developments of key fiber-based components employed in high-power laser systems.Subsequently,the emerging functional active and passive fibers in recent years,which exhibit tremendous advantages in balancing or mitigating parasitic nonlinearities hindering high-power transmission,are outlined from the perspectives of geo-metric and material engineering.Finally,novel functional applications of conventional fiber-based components for nonlinear suppression or spatial mode selection,and correspondingly,the high-power progress of function fiber-based components in power handling are introduced,which suggest more flexible controllability on high-power laser operations.
基金The authors are grateful for financial support from the Fundamental Research Funds for the Central Universities(2232021A-02)Shanghai Committee of Science and Technology,China(No.21ZR1480000)+1 种基金National Natural Science Foundation of China(No.52122312)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University.
文摘Fiber-based microplastics(FMPs)are highly persistent and ubiquitously exist in the wastewater of textile industry and urban sewage.It remains challenging to completely remove such newly emerged organic pollutants by the predominant physical techniques.In this work,we investigated a photocatalytic degradation catalyzed by TiO_(2) catalyst to demonstrate the feasibility of implementing efficient chemical protocol to fast degrading polyethylene terephthalate(PET)-FMPs(a major FMP type existing in environment).The result shows that a hydrothermal pretreatment(180℃/12 h)is necessary to induce the initial rough appearance and molecular weight reduction.With the comprehensive action of the nano-flower shaped N doped-TiO_(2) catalyst(Pt@N-TiO_(2)-1.5%)on the relatively low molecular weight intermediates,an approximate 29%weight loss was induced on the pretreated PET-FMPs,which is about 8 times superior to the untreated sample.This work not only achieves a superior degradation effect of PET-FMPs,but also provides a new inspiration for the proposal of reduction strategies in the field of environmental remediation in the future.
基金We are grateful for the financial support from State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University(Grant No.KF2112)National Natural Science Foundation of China(Grant No.22074010)+1 种基金National Key Research and Development Program of China(Grant No.2018AAA0100300,2020YFB2008502)Zhang Dayu School of Chemistry,Dalian University of Technology,China.
文摘Wearable fiber-based electronics have found diverse applications including energy storage,healthcare or thermal management,etc.In particular,additive-free aqueous inks play significant roles in fabrication of wearable fiber-based devices,owning to their nontoxic nature and ease of manufacturing.Herein,wearable carbon fiber-based asymmetric supercapacitors(WASSC)are developed based on additive-free aqueous MXene inks,for self-powering healthcare sensors.The sediments of MXene without further modification are used as inks.Furthermore,combined with additive-free aqueous MXene/polyaniline(MP)inks,WASSC,with a wide voltage window and high capacitance is developed for practical energy supply.Impressively,WASSC has been successfully utilized to power wearable pressure sensors that could monitor motions and pulse signals.This wearable self-powered monitoring system on can accurately monitor the human motions,pronunciation,swallow or wrist pulse,without using the rigid batteries.This advantage realizes a great potential in simple and cost effective monitoring of human health and activities.Besides,self-powered system enables waste recycling of MXene and provides an effective approach for designing wearable and fiber-based self-powered sensors.
