Conformable and breathable textile structures are ideal for flexible wearable pressure sensors,yet challenges remain in scalable fabrication,easy integration,and programmability.This study presents a cost-effective an...Conformable and breathable textile structures are ideal for flexible wearable pressure sensors,yet challenges remain in scalable fabrication,easy integration,and programmability.This study presents a cost-effective and customizable method to create fully textile-based pressure sensors using machine embroidery,enabling seamless integration into smart wearable systems.Two sensing configurations were developed:a single-layer satin block embroidered with conductive yarn,which exhibited high piezoresistivity,fast response(35 ms),quick recovery(16 ms),and robust durability over 5000 press-andrelease cycles,proven effective for monitoring activities such as plantar pressure and muscle contraction,and making it suitable for personalized health and fitness applications.The second configuration,a double-layer embroidery sensor with a conductive path and two parallel spacers anchored beneath a satin block,allows for array integration with minimal wiring,demonstrated by a 3×3 sensing array that,with the help of a convolutional neural network(CNN)machine learning model,accurately recognized handwritten numbers(0-9)with a 98.5%accuracy,showing its potential for user authentication and secure passcode entry.These findings underscore the potential of machine embroidery for developing scalable,integrated,and high-performance intelligent textile systems,paving the way for wearable technologies that are customizable,comfortable,and aesthetically appealing for a wide range of applications.展开更多
The rapid growth of wearable technology has significantly enhanced the capabilities of wearable sensors,transitioning from simple attachments of rigid electronics to the more comfortable and adaptable integration with...The rapid growth of wearable technology has significantly enhanced the capabilities of wearable sensors,transitioning from simple attachments of rigid electronics to the more comfortable and adaptable integration with soft substrates.Among these,flexible piezoresistive pressure sensors are particularly notable for their straightforward and reliable signal readout.Fiber,yarn,and textile-based sensors,which allow for multiscale material and structural engineering,present ideal solu-tions for achieving sensors with excellent wearability,sensitivity,and scalability potential.Innovations in materials and the advancement of artificial intelligence(AI)have further enhanced sensor performance,adding multifunctional capabilities and broadening their applications.This review systematically examines fiber,yarn,and textile-based piezoresistive pressure sensors,covering fundamental mechanisms,key performance metrics,conductive and substrate materials,structural designs,fabrication techniques,multifunctional integrations,and advanced applications in healthcare,fitness,and human–machine interaction,augmented by machine learning(ML).Finally,the review discusses sensor design and technical considerations,material–structure–property engineering,scalable production,performance evaluation,and offers recommendations and prospects for future sensor research and development.This comprehensive overview aims to provide a deeper understanding of current innovations and challenges,facilitating the advancement of flexible and intelligent wearable sensing technologies.展开更多
An anti-icing surface has been designed and prepared with an aluminum panel by creating an artificial lotus leaf which is highly hydrophobic. The hydrophobicity of a solid surface can be generated by decreasing its su...An anti-icing surface has been designed and prepared with an aluminum panel by creating an artificial lotus leaf which is highly hydrophobic. The hydrophobicity of a solid surface can be generated by decreasing its surface tension and increasing the roughness of the surface. On a highly hydrophobic surface, water has a high contact angle and it can easily rolls off, carrying surface dirt and debris with it. Super-cooled water or freezing rain can also run off this highly hydrophobic surface instead of forming ice on the surface, due to the reduction of the liquid-solid adhesion. This property can also help a surface to get rid of the ice after the water becomes frozen. In this study, a Cassie-Baxter rough surface was modeled, and an aluminum panel was physically and chemically modified based on the modeled structure. Good agreement was found between predicted values and experimental results for the contact and roll-off angles of water. Most importantly, by creating this highly hydrophobic aluminum rough surface, the anti-icing and de-icing properties of the modified surface were drastically improved compared to the control aluminum surface, and the cost will be reduced.展开更多
As the global population continues growing, the demand for textiles also increases, putting pres- sure on cotton manufacturers to produce more natural fiber from this already undersupplied resource. Synthetic fibers s...As the global population continues growing, the demand for textiles also increases, putting pres- sure on cotton manufacturers to produce more natural fiber from this already undersupplied resource. Synthetic fibers such as polyester (PET) can be manufactured quickly and cheaply, but these petroleum-based products are detrimental to the environment. With increased efforts to encourage transparency and create a more circular textile economy, other natural alternatives must be considered. This article discusses the existing condition and future possibilities for man- made cellulosic fibers (MMCFs), with an emphasis on using non-woody alternative feedstocks as a starting material. This work focuses on conversion technology suitable for producing textile- grade fibers from non-wood-based dissolving pulp, which may be different in nature from its woody counterpart and therefore behave differently in spinning processes. Derivatization and dissolution methods are detailed, along with spinning techniques and parameters for these pro- cesses. Existing research related to the spinning of non-woody-based dissolving pulp is covered, along with suggestions for the most promising feedstock and technology combinations. In addi- tion, an emerging method of conversion, in which textile fibers are spun from a hydrogel made of an undissolved nano/micro-fibrillated fiber suspension, is briefly discussed due to its unique po- tential. Methods and concepts compiled in this review relate to utilizing alternative feedstocks for future fibers while providing a better understanding of conventional and emerging fiber spinning processes for these fibers.展开更多
室温下,用醋酸硝酰(浓硝酸与冰醋酸混合物)将10-羟基-5,10-二氢磷杂吖嗪-10-氧化物硝化5 h,得10-羟基-2-硝基-5,10-二氢磷杂吖嗪-10-氧化物(74%)。后者在中性介质中,用5%Pd/C作催化剂,氢化还原得到2-氨基-10-羟基-5,10-二氢磷杂吖嗪-10...室温下,用醋酸硝酰(浓硝酸与冰醋酸混合物)将10-羟基-5,10-二氢磷杂吖嗪-10-氧化物硝化5 h,得10-羟基-2-硝基-5,10-二氢磷杂吖嗪-10-氧化物(74%)。后者在中性介质中,用5%Pd/C作催化剂,氢化还原得到2-氨基-10-羟基-5,10-二氢磷杂吖嗪-10-氧化物(70%)。经过Salmonella/m amm alian m icrosom e assay测试,该氨基物表现为非诱变性,用它作为重氮组分,分别与3种吡唑啉酮系衍生物偶合得到3种红色酸性偶氮染料。研究了这些染料的光谱性质及其应用性能。结果表明,所合成的新染料比由一般芳香胺与吡唑啉酮形成的偶氮化合物具有深色效应。用波谱分析确定了中间体及其染料的结构。展开更多
As the global population grows,the demand for textiles is increasing rapidly.However,this puts immense pressure on manufacturers to produce more fiber.While synthetic fibers can be pro-duced cheaply,they have a negati...As the global population grows,the demand for textiles is increasing rapidly.However,this puts immense pressure on manufacturers to produce more fiber.While synthetic fibers can be pro-duced cheaply,they have a negative impact on the environment.On the other hand,fibers from wool,sisal,fique,wood pulp(viscose),and man-made cellulose fibers(MMCFs)from cotton can-not alone meet the growing fiber demand without major stresses on land,water,and existing markets using these materials.With a greater emphasis on transparency and circular economy practices,there is a need to consider natural non-wood alternative sources for MMCFs to supple-ment other fiber types.However,introducing new feedstocks with different compositions may require different biomass conversion methods.Therefore,based on existing work,this review ad-dresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers.First,alternative feedstocks are introduced,and then conventional(dissolving pulp)and emerging(fibrillated cellulose and recycled material)conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose.It is important to note that for alternative feedstocks to be adopted on a meaningful scale,high biomass availability and proximity of conversion facilities are critical factors.In North America,soybean,wheat,rice,sorghum,and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods(pre-hydrolysis kraft,acid sulfite,soda,SO2-ethanol-water,and potassium hydroxide)or by emerging cellulose fibrillation methods.While dissolving pulp conversion is well-established,fibrillated cel-lulose methods could be beneficial from cost,efficiency,and environmental perspectives.Thus,the authors strongly encourage more work in this growing research area.However,conducting thorough cost and sustainability assessments is important to determine the best feedstock and technology combinations.展开更多
In burn treatments,microorganisms on pressure garments during pressure therapy can prevent rehabilitation by causing functional,hygienic,and aesthetic difficulties. As bacterium is one of the most trouble-causing orga...In burn treatments,microorganisms on pressure garments during pressure therapy can prevent rehabilitation by causing functional,hygienic,and aesthetic difficulties. As bacterium is one of the most trouble-causing organisms,they can threaten patients causing infection during the long period of use of these garments.Novel burn pressure garments having durable antimicrobial property were developed using polyhexamethylene biguanide( PHMB)antimicrobial agent procedure on highly elastic nylon 66 /spandex fabrics in powernet,flat warp and weft knitted structures using paddry-cure method. Commercial wireless pressure sensors were used to control pressures at an acceptable medical range. Antimicrobial activity,wash durability,Fourier transform infrared spectroscopy(FTIR) and Scanning electron microscopy(SEM) analyses were conducted for the treated samples. Antimicrobial test results following AATCC 100 Test Method showed 99% reduction of bacteria for the fabric samples treated with PHMB. A small but significant decrease in antimicrobial activity was observed even after50 launderings. These treatments also yield good results to prevent odor,decrease infection by preventing and /or blocking microbial growth according to the antimicrobial mechanism and support reducing of scarring by providing a hygienic environment around the scar.展开更多
The development of advanced bifunctional oxygen electrocatalysts for oxygen reduction and evolution reactions(ORR and OER) is critical to the practical application of zinc-air batteries(ZABs). Herein, a silica-assiste...The development of advanced bifunctional oxygen electrocatalysts for oxygen reduction and evolution reactions(ORR and OER) is critical to the practical application of zinc-air batteries(ZABs). Herein, a silica-assisted method is reported to integrate numerous accessible edge Fe-Nx sites into porous graphitic carbon(named Fe-N-G) for achieving highly active and robust oxygen electrocatalysis. Silica facilitates the formation of edge Fe-Nx sites and dense graphitic domains in carbon by inhibiting iron aggregation.The purification process creates a well-developed mass transfer channel for Fe-N-G. Consequently,Fe-N-G delivers a half-wave potential of 0.859 V in ORR and an overpotential of 344 m V at10 m A cm^(-2)in OER. During long-term operation, the graphitic layers protect edge Fe-Nx sites from demetallation in ORR and synergize with Fe OOH species endowing Fe-N-G with enhanced OER activity.Density functional theory calculations reveal that the edge Fe-Nx site is superior to the in-plane Fe-Nx site in terms of OH* dissociation in ORR and OOH* formation in OER. The constructed ZAB based on Fe-N-G cathode shows a higher peak power density of 133 m W cm^(-2)and more stable cycling performance than Pt/C + RuO2counterparts. This work provides a novel strategy to obtain high-efficiency bifunctional oxygen electrocatalysts through space mediation.展开更多
Li2MnSiO4 has an extremely high theoretical capacity of 332 mAh?g?1. However, only around half of this capacity has been realized in practice and the capacity retention during cycling is also low. In this study, Li2Mn...Li2MnSiO4 has an extremely high theoretical capacity of 332 mAh?g?1. However, only around half of this capacity has been realized in practice and the capacity retention during cycling is also low. In this study, Li2MnSiO4/carbon composite nanofibers were prepared by a combination of electrospinning and heat treatment. The one-dimensional continuous carbon nanofiber matrix serves as long-distance conductive pathways for both electrons and ions. The composite nanofiber structure avoids the aggregation of Li2MnSiO4 particles, which in turn enhances the electrode conductivity and promotes the reaction kinetics. The resultant Li2MnSiO4/carbon composite nanofibers were used as the cathode material for Li-ion batteries, and they delivered high charge and discharge capacities of 218 and 185 mAh?g?1, respectively, at the second cycle. In addition, the capacity retention of Li2MnSiO4 at the first 20th cycles increased from 37% to 54% in composite nanofibers.展开更多
Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolyte...Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolytes,composite solid electrolytes(CSEs)exhibit both high ionic conductivity and excellent interfacial contact with the electrodes.Incorporating active nanofib-ers into the polymer matrix demonstrates an effective method to fabricate CSEs.However,current CSEs based on traditional poly(ethylene oxide)(PEO)polymer suffer from the poor ionic conductivity of PEO and agglomeration effect of inorganic fillers at high concentrations,which limit further improvements in Li+conductivity and electrochemical stability.Herein,we synthesize a novel PEO based cross-linked polymer(CLP)as the polymer matrix with naturally amorphous structure and high room-temperature ionic conductivity of 2.40×10^(−4)S cm^(−1).Li_(0.3)La_(0.557)TiO_(3)(LLTO)nanofibers are incorporated into the CLP matrix to form composite solid electrolytes,achieving enhanced ionic conductivity without showing filler agglomeration.The high content of Li-conductive nanofibers improves the mechanical strength,ensures the conductive network,and increases the total Li+conductivity to 3.31×10^(−4)S cm^(−1).The all-solid-state Li|LiFePO_(4)batteries with LLTO nanofiber-incorporated CSEs are able to deliver attractive specific capacity of 147 mAh g^(−1)at room temperature,and no evident dendrite is found at the anode/electrolyte interface after 100 cycles.展开更多
Wearable electronics offer incredible benefits in mobile healthcare monitoring,sensing,portable energy harvesting and storage,human-machine interactions,etc.,due to the evolution of rigid electronics structure to flex...Wearable electronics offer incredible benefits in mobile healthcare monitoring,sensing,portable energy harvesting and storage,human-machine interactions,etc.,due to the evolution of rigid electronics structure to flexible and stretchable devices.Lately,transition metal carbides and nitrides(MXenes)are highly regarded as a group of thriving two-dimensional nanomaterials and extraordinary building blocks for emerging flexible electronics platforms because of their excellent electrical conductivity,enriched surface functionalities,and large surface area.This article reviews the most recent developments in MXene-enabled flexible electronics for wearable electronics.Several MXeneenabled electronic devices designed on a nanometric scale are highlighted by drawing attention to widely developed nonstructural attributes,including 3D configured devices,textile and planer substrates,bioinspired structures,and printed materials.Furthermore,the unique progress of these nanodevices is highlighted by representative applications in healthcare,energy,electromagnetic interference(EMI)shielding,and humanoid control of machines.The emerging prospects of MXene nanomaterials as a key frontier in nextgeneration wearable electronics are envisioned and the design challenges of these electronic systems are also discussed,followed by proposed solutions.展开更多
Skin-mounted wearable electronics are attractive for continuous health monitoring and human-machine interfacing.The commonly used pre-gelled rigid and bulky electrodes cause discomfort and are unsuitable for continuou...Skin-mounted wearable electronics are attractive for continuous health monitoring and human-machine interfacing.The commonly used pre-gelled rigid and bulky electrodes cause discomfort and are unsuitable for continuous long-term monitoring applications.Here,we design carbon nanotubes(CNTs)-based electrodes that can be fabricated using different textile manufacturing processes.We propose woven and braided electrode design using CNTs wrapped textile yarns which are highly conformable to skin and measure a high-fidelity electrocardiography(ECG)signal.The skin-electrode impedance analysis revealed size-dependent behavior.To demonstrate outstanding wearability,we designed a seamless knit electrode that can be worn as a bracelet.The designed CNT-based dry electrodes demonstrated record high signal-to-noise ratios and were very stable against motion artifacts.The durability test of the electrodes exhibited robustness to laundering and practicality for reusable and sustainable applications.展开更多
Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the...Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the yield increased significantly to 26.6 wt%when bio-diesel was the extractant.The molecular weight of fpBO before and after extraction were consistent with the loss of a more soluble,low molecular weight fraction from the crude fpBO.The relative energy difference(RED),based on the Hansen solubility parameter(HSP),is used to examine the extraction efficiency of specific compounds in the two different‘solvents’.Differences in the RED values could be used to rationalize differences in the partitioning of common fpBO phenolics.展开更多
Multidimensional single-molecule localization microscopy(mSMLM)represents a paradigm shift in the realm of super-resolution microscopy techniques.It affords the simultaneous detection of singlemolecule spatial locatio...Multidimensional single-molecule localization microscopy(mSMLM)represents a paradigm shift in the realm of super-resolution microscopy techniques.It affords the simultaneous detection of singlemolecule spatial locations at the nanoscale and functional information by interrogating the emission properties of switchable fluorophores.The latter is finely tuned to report its local environment through carefully manipulated laser illumination and single-molecule detection strategies.This Perspective highlights recent strides in mSMLM with a focus on fluorophore designs and their integration into mSMLM imaging systems.Particular interests are the accomplishments in simultaneous multiplexed super-resolution imaging,nanoscale polarity and hydrophobicity mapping,and single-molecule orientational imaging.Challenges and prospects in mSMLM are also discussed,which include the development of more vibrant and functional fluorescent probes,the optimization of optical implementation to judiciously utilize the photon budget,and the advancement of imaging analysis and machine learning techniques.展开更多
The lithium-ion(Li-ion)battery has received considerable attention in the field of energy conversion and storage due to its high energy density and eco-friendliness.Significant academic and commercial progress has bee...The lithium-ion(Li-ion)battery has received considerable attention in the field of energy conversion and storage due to its high energy density and eco-friendliness.Significant academic and commercial progress has been made in Li-ion battery technologies.One area of advancement has been the addition of nanofiber materials to Li-ion batteries due to their unique and desirable structural features including large aspect ratios,high surface areas,controllable chemical compositions,and abundant composite forms.In the past few decades,considerable research efforts have been devoted to constructing advanced nanofiber materials possessing conductive networks to facilitate efficient electron transport and large specific surface areas to support catalytically active sites,both for the purpose of boosting electrochemical performance.Herein,we focus on recent advancements of nanofiber materials with carefully designed structures and enhanced electrochemical properties for use in Li-ion batteries.The synthesis,structure,and properties of nanofiber cathodes,anodes,separators,and electrolytes,and their applications in Li-ion batteries are discussed.The research challenges and prospects of nanofiber materials in Li-ion battery applications are delineated.展开更多
Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect ...Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect in conventional dual-ion polymer electrolytes.Addition of a plasticizer into the polymer matrix confers advantages of both liquid and solid electrolytes.However,plasticized SIPEs usually face a trade-of between conductivity and mechanical strength.With insufcient strength,potentially there is short-circuiting failure during cycling.To address this challenge,a simple and mechanicallyrobust SIPE was developed by crosslinking monomer lithium(4-styrenesulfonyl)(trifuoromethylsulfonyl)imide(LiSTFSI)and crosslinker poly(ethylene glycol)diacrylate(PEGDA),with plasticizer propylene carbonate(PC),on electrospun polyacrylonitrile nanofbers(PAN-NFs).The well-fabricated polymer matrix provided fast and efective Li^(+) conductive pathways with a remarkable ionic conductivity of 8.09×10^(-4) S cm^(−1) and a superior lithium-ion transference number close to unity(t_(Li+)=0.92).The introduction of PAN-NFs not only improved the mechanical strength and fexibility but also endowed the plasticized SIPE with a wide electrochemical stability window(4.9 V vs.Li^(+)/Li)and better cycling stability.Superior longterm lithium cycling stability and dynamic interfacial compatibility were demonstrated by lithium symmetric cell testing.Most importantly,the assembled all-solid-state Li metal batteries showed stable cycling performance and remarkable rate capability both in low and high current densities.Therefore,this straightforward and mechanically reinforced SIPE exhibits great potential in the development of advanced all-solid-state Li-metal batteries.展开更多
Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the applicatio...Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the application of conventional CC-based electrodes for zinc(Zn)storage severely hinders Zn ion transport and induces deleterious Zn dendrite growth,resulting in poor electrochemical reliability.Herein,a novel oxygen plasma-treated carbon cloth(OPCC)is rationally designed as a current collector for flexible hybrid Zn ion supercapacitors(ZISs).The modified interface of OPCC with abundant oxygenated groups enables enhanced electrolyte wettability and uniform superficial electric field distribution.A prolonged working lifespan for Zn electrodeposition is achieved by the OPCC due to the improved interfacial kinetics and homogenized ion gradient.The as-prepared hybrid ZIS also delivers excellent cycling endurance(98.5%capacity retention for 1500 cycles)with outstanding operation stability under various extreme conditions.This facile surface modification strategy provides a new way for developing future flexible electrodes for wearable electronic products.展开更多
Soft fluidic devices are important for wearable applications involving mass and heat transfer.Based on charge injection electrohydrodynamics,a fluidic fiber pump made of polyurethane and copper wires has been reported...Soft fluidic devices are important for wearable applications involving mass and heat transfer.Based on charge injection electrohydrodynamics,a fluidic fiber pump made of polyurethane and copper wires has been reported to show outstanding performances in terms of pressure,flow rate and power density.Its flexible fiber shape allows integration compatible with textiles,opening new possibilities in the ever-growing field of wearable technology.展开更多
文摘Conformable and breathable textile structures are ideal for flexible wearable pressure sensors,yet challenges remain in scalable fabrication,easy integration,and programmability.This study presents a cost-effective and customizable method to create fully textile-based pressure sensors using machine embroidery,enabling seamless integration into smart wearable systems.Two sensing configurations were developed:a single-layer satin block embroidered with conductive yarn,which exhibited high piezoresistivity,fast response(35 ms),quick recovery(16 ms),and robust durability over 5000 press-andrelease cycles,proven effective for monitoring activities such as plantar pressure and muscle contraction,and making it suitable for personalized health and fitness applications.The second configuration,a double-layer embroidery sensor with a conductive path and two parallel spacers anchored beneath a satin block,allows for array integration with minimal wiring,demonstrated by a 3×3 sensing array that,with the help of a convolutional neural network(CNN)machine learning model,accurately recognized handwritten numbers(0-9)with a 98.5%accuracy,showing its potential for user authentication and secure passcode entry.These findings underscore the potential of machine embroidery for developing scalable,integrated,and high-performance intelligent textile systems,paving the way for wearable technologies that are customizable,comfortable,and aesthetically appealing for a wide range of applications.
基金supported by the Wilson College Strategic Collaborative Research&Innovation Fund(PINS 131769)at NCSU.Yiduo Yang acknowledges the financial support of the Provost’s Doctoral Fellowship and Goodnight Doctoral Fellowship at NCSU.
文摘The rapid growth of wearable technology has significantly enhanced the capabilities of wearable sensors,transitioning from simple attachments of rigid electronics to the more comfortable and adaptable integration with soft substrates.Among these,flexible piezoresistive pressure sensors are particularly notable for their straightforward and reliable signal readout.Fiber,yarn,and textile-based sensors,which allow for multiscale material and structural engineering,present ideal solu-tions for achieving sensors with excellent wearability,sensitivity,and scalability potential.Innovations in materials and the advancement of artificial intelligence(AI)have further enhanced sensor performance,adding multifunctional capabilities and broadening their applications.This review systematically examines fiber,yarn,and textile-based piezoresistive pressure sensors,covering fundamental mechanisms,key performance metrics,conductive and substrate materials,structural designs,fabrication techniques,multifunctional integrations,and advanced applications in healthcare,fitness,and human–machine interaction,augmented by machine learning(ML).Finally,the review discusses sensor design and technical considerations,material–structure–property engineering,scalable production,performance evaluation,and offers recommendations and prospects for future sensor research and development.This comprehensive overview aims to provide a deeper understanding of current innovations and challenges,facilitating the advancement of flexible and intelligent wearable sensing technologies.
文摘An anti-icing surface has been designed and prepared with an aluminum panel by creating an artificial lotus leaf which is highly hydrophobic. The hydrophobicity of a solid surface can be generated by decreasing its surface tension and increasing the roughness of the surface. On a highly hydrophobic surface, water has a high contact angle and it can easily rolls off, carrying surface dirt and debris with it. Super-cooled water or freezing rain can also run off this highly hydrophobic surface instead of forming ice on the surface, due to the reduction of the liquid-solid adhesion. This property can also help a surface to get rid of the ice after the water becomes frozen. In this study, a Cassie-Baxter rough surface was modeled, and an aluminum panel was physically and chemically modified based on the modeled structure. Good agreement was found between predicted values and experimental results for the contact and roll-off angles of water. Most importantly, by creating this highly hydrophobic aluminum rough surface, the anti-icing and de-icing properties of the modified surface were drastically improved compared to the control aluminum surface, and the cost will be reduced.
基金the financial support by the USDA National Needs Fellowship Program(Grant 12513354,project NCZ09489,“Developing Expertise in Risk Analysis and Risk Management for the Bioeconomy”).
文摘As the global population continues growing, the demand for textiles also increases, putting pres- sure on cotton manufacturers to produce more natural fiber from this already undersupplied resource. Synthetic fibers such as polyester (PET) can be manufactured quickly and cheaply, but these petroleum-based products are detrimental to the environment. With increased efforts to encourage transparency and create a more circular textile economy, other natural alternatives must be considered. This article discusses the existing condition and future possibilities for man- made cellulosic fibers (MMCFs), with an emphasis on using non-woody alternative feedstocks as a starting material. This work focuses on conversion technology suitable for producing textile- grade fibers from non-wood-based dissolving pulp, which may be different in nature from its woody counterpart and therefore behave differently in spinning processes. Derivatization and dissolution methods are detailed, along with spinning techniques and parameters for these pro- cesses. Existing research related to the spinning of non-woody-based dissolving pulp is covered, along with suggestions for the most promising feedstock and technology combinations. In addi- tion, an emerging method of conversion, in which textile fibers are spun from a hydrogel made of an undissolved nano/micro-fibrillated fiber suspension, is briefly discussed due to its unique po- tential. Methods and concepts compiled in this review relate to utilizing alternative feedstocks for future fibers while providing a better understanding of conventional and emerging fiber spinning processes for these fibers.
文摘室温下,用醋酸硝酰(浓硝酸与冰醋酸混合物)将10-羟基-5,10-二氢磷杂吖嗪-10-氧化物硝化5 h,得10-羟基-2-硝基-5,10-二氢磷杂吖嗪-10-氧化物(74%)。后者在中性介质中,用5%Pd/C作催化剂,氢化还原得到2-氨基-10-羟基-5,10-二氢磷杂吖嗪-10-氧化物(70%)。经过Salmonella/m amm alian m icrosom e assay测试,该氨基物表现为非诱变性,用它作为重氮组分,分别与3种吡唑啉酮系衍生物偶合得到3种红色酸性偶氮染料。研究了这些染料的光谱性质及其应用性能。结果表明,所合成的新染料比由一般芳香胺与吡唑啉酮形成的偶氮化合物具有深色效应。用波谱分析确定了中间体及其染料的结构。
文摘As the global population grows,the demand for textiles is increasing rapidly.However,this puts immense pressure on manufacturers to produce more fiber.While synthetic fibers can be pro-duced cheaply,they have a negative impact on the environment.On the other hand,fibers from wool,sisal,fique,wood pulp(viscose),and man-made cellulose fibers(MMCFs)from cotton can-not alone meet the growing fiber demand without major stresses on land,water,and existing markets using these materials.With a greater emphasis on transparency and circular economy practices,there is a need to consider natural non-wood alternative sources for MMCFs to supple-ment other fiber types.However,introducing new feedstocks with different compositions may require different biomass conversion methods.Therefore,based on existing work,this review ad-dresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers.First,alternative feedstocks are introduced,and then conventional(dissolving pulp)and emerging(fibrillated cellulose and recycled material)conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose.It is important to note that for alternative feedstocks to be adopted on a meaningful scale,high biomass availability and proximity of conversion facilities are critical factors.In North America,soybean,wheat,rice,sorghum,and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods(pre-hydrolysis kraft,acid sulfite,soda,SO2-ethanol-water,and potassium hydroxide)or by emerging cellulose fibrillation methods.While dissolving pulp conversion is well-established,fibrillated cel-lulose methods could be beneficial from cost,efficiency,and environmental perspectives.Thus,the authors strongly encourage more work in this growing research area.However,conducting thorough cost and sustainability assessments is important to determine the best feedstock and technology combinations.
基金Financial support of this research was provided by NC State University College of Textilesthe Scientific and Technological Research Council of Turkey
文摘In burn treatments,microorganisms on pressure garments during pressure therapy can prevent rehabilitation by causing functional,hygienic,and aesthetic difficulties. As bacterium is one of the most trouble-causing organisms,they can threaten patients causing infection during the long period of use of these garments.Novel burn pressure garments having durable antimicrobial property were developed using polyhexamethylene biguanide( PHMB)antimicrobial agent procedure on highly elastic nylon 66 /spandex fabrics in powernet,flat warp and weft knitted structures using paddry-cure method. Commercial wireless pressure sensors were used to control pressures at an acceptable medical range. Antimicrobial activity,wash durability,Fourier transform infrared spectroscopy(FTIR) and Scanning electron microscopy(SEM) analyses were conducted for the treated samples. Antimicrobial test results following AATCC 100 Test Method showed 99% reduction of bacteria for the fabric samples treated with PHMB. A small but significant decrease in antimicrobial activity was observed even after50 launderings. These treatments also yield good results to prevent odor,decrease infection by preventing and /or blocking microbial growth according to the antimicrobial mechanism and support reducing of scarring by providing a hygienic environment around the scar.
基金financial support from the National Key Research and Development Project (2017YFB0308200)the CAS Key Laboratory of Carbon Materials (KLCMKFJJ2011)。
文摘The development of advanced bifunctional oxygen electrocatalysts for oxygen reduction and evolution reactions(ORR and OER) is critical to the practical application of zinc-air batteries(ZABs). Herein, a silica-assisted method is reported to integrate numerous accessible edge Fe-Nx sites into porous graphitic carbon(named Fe-N-G) for achieving highly active and robust oxygen electrocatalysis. Silica facilitates the formation of edge Fe-Nx sites and dense graphitic domains in carbon by inhibiting iron aggregation.The purification process creates a well-developed mass transfer channel for Fe-N-G. Consequently,Fe-N-G delivers a half-wave potential of 0.859 V in ORR and an overpotential of 344 m V at10 m A cm^(-2)in OER. During long-term operation, the graphitic layers protect edge Fe-Nx sites from demetallation in ORR and synergize with Fe OOH species endowing Fe-N-G with enhanced OER activity.Density functional theory calculations reveal that the edge Fe-Nx site is superior to the in-plane Fe-Nx site in terms of OH* dissociation in ORR and OOH* formation in OER. The constructed ZAB based on Fe-N-G cathode shows a higher peak power density of 133 m W cm^(-2)and more stable cycling performance than Pt/C + RuO2counterparts. This work provides a novel strategy to obtain high-efficiency bifunctional oxygen electrocatalysts through space mediation.
文摘Li2MnSiO4 has an extremely high theoretical capacity of 332 mAh?g?1. However, only around half of this capacity has been realized in practice and the capacity retention during cycling is also low. In this study, Li2MnSiO4/carbon composite nanofibers were prepared by a combination of electrospinning and heat treatment. The one-dimensional continuous carbon nanofiber matrix serves as long-distance conductive pathways for both electrons and ions. The composite nanofiber structure avoids the aggregation of Li2MnSiO4 particles, which in turn enhances the electrode conductivity and promotes the reaction kinetics. The resultant Li2MnSiO4/carbon composite nanofibers were used as the cathode material for Li-ion batteries, and they delivered high charge and discharge capacities of 218 and 185 mAh?g?1, respectively, at the second cycle. In addition, the capacity retention of Li2MnSiO4 at the first 20th cycles increased from 37% to 54% in composite nanofibers.
基金the Department of Energy,Office of Energy Efficiency and Renewable Energy(EERE),under Award Number DE-EE0007806.
文摘Solid electrolytes have gained attention recently for the development of next-generation Li-ion batteries since they can fun-damentally improve the battery stability and safety.Among various types of solid electrolytes,composite solid electrolytes(CSEs)exhibit both high ionic conductivity and excellent interfacial contact with the electrodes.Incorporating active nanofib-ers into the polymer matrix demonstrates an effective method to fabricate CSEs.However,current CSEs based on traditional poly(ethylene oxide)(PEO)polymer suffer from the poor ionic conductivity of PEO and agglomeration effect of inorganic fillers at high concentrations,which limit further improvements in Li+conductivity and electrochemical stability.Herein,we synthesize a novel PEO based cross-linked polymer(CLP)as the polymer matrix with naturally amorphous structure and high room-temperature ionic conductivity of 2.40×10^(−4)S cm^(−1).Li_(0.3)La_(0.557)TiO_(3)(LLTO)nanofibers are incorporated into the CLP matrix to form composite solid electrolytes,achieving enhanced ionic conductivity without showing filler agglomeration.The high content of Li-conductive nanofibers improves the mechanical strength,ensures the conductive network,and increases the total Li+conductivity to 3.31×10^(−4)S cm^(−1).The all-solid-state Li|LiFePO_(4)batteries with LLTO nanofiber-incorporated CSEs are able to deliver attractive specific capacity of 147 mAh g^(−1)at room temperature,and no evident dendrite is found at the anode/electrolyte interface after 100 cycles.
文摘Wearable electronics offer incredible benefits in mobile healthcare monitoring,sensing,portable energy harvesting and storage,human-machine interactions,etc.,due to the evolution of rigid electronics structure to flexible and stretchable devices.Lately,transition metal carbides and nitrides(MXenes)are highly regarded as a group of thriving two-dimensional nanomaterials and extraordinary building blocks for emerging flexible electronics platforms because of their excellent electrical conductivity,enriched surface functionalities,and large surface area.This article reviews the most recent developments in MXene-enabled flexible electronics for wearable electronics.Several MXeneenabled electronic devices designed on a nanometric scale are highlighted by drawing attention to widely developed nonstructural attributes,including 3D configured devices,textile and planer substrates,bioinspired structures,and printed materials.Furthermore,the unique progress of these nanodevices is highlighted by representative applications in healthcare,energy,electromagnetic interference(EMI)shielding,and humanoid control of machines.The emerging prospects of MXene nanomaterials as a key frontier in nextgeneration wearable electronics are envisioned and the design challenges of these electronic systems are also discussed,followed by proposed solutions.
基金supported by the Analytical Instrumentation Facility (AIF) at North Carolina State Universitysupported by the State of North Carolina and the National Science Foundation (award number ECCS-1542015).
文摘Skin-mounted wearable electronics are attractive for continuous health monitoring and human-machine interfacing.The commonly used pre-gelled rigid and bulky electrodes cause discomfort and are unsuitable for continuous long-term monitoring applications.Here,we design carbon nanotubes(CNTs)-based electrodes that can be fabricated using different textile manufacturing processes.We propose woven and braided electrode design using CNTs wrapped textile yarns which are highly conformable to skin and measure a high-fidelity electrocardiography(ECG)signal.The skin-electrode impedance analysis revealed size-dependent behavior.To demonstrate outstanding wearability,we designed a seamless knit electrode that can be worn as a bracelet.The designed CNT-based dry electrodes demonstrated record high signal-to-noise ratios and were very stable against motion artifacts.The durability test of the electrodes exhibited robustness to laundering and practicality for reusable and sustainable applications.
基金IBSS project funded by Agriculture and Food Research Initiative Competitive Grant no.2011-68005-30410 from the USDA National Institute of Food and Agriculture.
文摘Fast pyrolysis bio-oils(fpBO)were extracted with two alternative commercial transportation fuels,hydrocarbon diesel and bio-diesel.The extraction of fpBO with commercial diesel fuel provided a yield of 4.3 wt%,but the yield increased significantly to 26.6 wt%when bio-diesel was the extractant.The molecular weight of fpBO before and after extraction were consistent with the loss of a more soluble,low molecular weight fraction from the crude fpBO.The relative energy difference(RED),based on the Hansen solubility parameter(HSP),is used to examine the extraction efficiency of specific compounds in the two different‘solvents’.Differences in the RED values could be used to rationalize differences in the partitioning of common fpBO phenolics.
基金supported by the National Institutes of Health grants R21GM141675 and R01GM143397the National Science Foundation grant CHM-1954430 and CHM-2246548the National Research Foundation of Korea grant No.NRF-2022R1C1C1002850.
文摘Multidimensional single-molecule localization microscopy(mSMLM)represents a paradigm shift in the realm of super-resolution microscopy techniques.It affords the simultaneous detection of singlemolecule spatial locations at the nanoscale and functional information by interrogating the emission properties of switchable fluorophores.The latter is finely tuned to report its local environment through carefully manipulated laser illumination and single-molecule detection strategies.This Perspective highlights recent strides in mSMLM with a focus on fluorophore designs and their integration into mSMLM imaging systems.Particular interests are the accomplishments in simultaneous multiplexed super-resolution imaging,nanoscale polarity and hydrophobicity mapping,and single-molecule orientational imaging.Challenges and prospects in mSMLM are also discussed,which include the development of more vibrant and functional fluorescent probes,the optimization of optical implementation to judiciously utilize the photon budget,and the advancement of imaging analysis and machine learning techniques.
基金Samuel S.Walker Distinguished Professorship Fund of the Wilson College of Textiles,North Carolina State University,and the Natural Science Foundation of Hubei Province(No.2021CFB478),China.
文摘The lithium-ion(Li-ion)battery has received considerable attention in the field of energy conversion and storage due to its high energy density and eco-friendliness.Significant academic and commercial progress has been made in Li-ion battery technologies.One area of advancement has been the addition of nanofiber materials to Li-ion batteries due to their unique and desirable structural features including large aspect ratios,high surface areas,controllable chemical compositions,and abundant composite forms.In the past few decades,considerable research efforts have been devoted to constructing advanced nanofiber materials possessing conductive networks to facilitate efficient electron transport and large specific surface areas to support catalytically active sites,both for the purpose of boosting electrochemical performance.Herein,we focus on recent advancements of nanofiber materials with carefully designed structures and enhanced electrochemical properties for use in Li-ion batteries.The synthesis,structure,and properties of nanofiber cathodes,anodes,separators,and electrolytes,and their applications in Li-ion batteries are discussed.The research challenges and prospects of nanofiber materials in Li-ion battery applications are delineated.
基金This work was supported by the Samuel S.Walker Distinguished Professorship in the Wilson College of Textiles at North Carolina State University。
文摘Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect in conventional dual-ion polymer electrolytes.Addition of a plasticizer into the polymer matrix confers advantages of both liquid and solid electrolytes.However,plasticized SIPEs usually face a trade-of between conductivity and mechanical strength.With insufcient strength,potentially there is short-circuiting failure during cycling.To address this challenge,a simple and mechanicallyrobust SIPE was developed by crosslinking monomer lithium(4-styrenesulfonyl)(trifuoromethylsulfonyl)imide(LiSTFSI)and crosslinker poly(ethylene glycol)diacrylate(PEGDA),with plasticizer propylene carbonate(PC),on electrospun polyacrylonitrile nanofbers(PAN-NFs).The well-fabricated polymer matrix provided fast and efective Li^(+) conductive pathways with a remarkable ionic conductivity of 8.09×10^(-4) S cm^(−1) and a superior lithium-ion transference number close to unity(t_(Li+)=0.92).The introduction of PAN-NFs not only improved the mechanical strength and fexibility but also endowed the plasticized SIPE with a wide electrochemical stability window(4.9 V vs.Li^(+)/Li)and better cycling stability.Superior longterm lithium cycling stability and dynamic interfacial compatibility were demonstrated by lithium symmetric cell testing.Most importantly,the assembled all-solid-state Li metal batteries showed stable cycling performance and remarkable rate capability both in low and high current densities.Therefore,this straightforward and mechanically reinforced SIPE exhibits great potential in the development of advanced all-solid-state Li-metal batteries.
基金This work was financially supported by Natural Science Foundation of Jiangsu Province(BK20210480)Hong Kong Scholars Program(P0035017).
文摘Carbon cloth(CC)-based electrodes have attracted extensive attention for next-generation wearable energy-storage devices due to their excellent electrical conductivity and mechanical flexibility.However,the application of conventional CC-based electrodes for zinc(Zn)storage severely hinders Zn ion transport and induces deleterious Zn dendrite growth,resulting in poor electrochemical reliability.Herein,a novel oxygen plasma-treated carbon cloth(OPCC)is rationally designed as a current collector for flexible hybrid Zn ion supercapacitors(ZISs).The modified interface of OPCC with abundant oxygenated groups enables enhanced electrolyte wettability and uniform superficial electric field distribution.A prolonged working lifespan for Zn electrodeposition is achieved by the OPCC due to the improved interfacial kinetics and homogenized ion gradient.The as-prepared hybrid ZIS also delivers excellent cycling endurance(98.5%capacity retention for 1500 cycles)with outstanding operation stability under various extreme conditions.This facile surface modification strategy provides a new way for developing future flexible electrodes for wearable electronic products.
基金support from the Wilson College Strategic Collaborative Research and Innovation Fund(PINS 131769)Provost’s Doctoral Fellowship and Goodnight Doctoral Fellowship at NC State University。
文摘Soft fluidic devices are important for wearable applications involving mass and heat transfer.Based on charge injection electrohydrodynamics,a fluidic fiber pump made of polyurethane and copper wires has been reported to show outstanding performances in terms of pressure,flow rate and power density.Its flexible fiber shape allows integration compatible with textiles,opening new possibilities in the ever-growing field of wearable technology.
