Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We rece...Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We recently identified zona pellucida(Zp) as the top differentially expressed protein between East Asian cyprinids that produce adhesive and semi-buoyant eggs,suggesting that Zp protein may play important roles in the regulation of egg type.In this work,we generated transgenic zebrafish in which oocyte-specific expression of zp genes from rare minnow(Gobiocypris rarus),an East Asian cyprinid laying adhesive eggs,was driven by a zebrafish zp3.2 gene promoter.We found that the transgenic eggs obtained partial adhesiveness and exhibited alteration in hydration and buoyancy.Abnormal metabolism of vitellogenin(VTG) may contribute to enhanced hydration and/or buoyancy.Our work shows that expression of the exogenous zp3a gene from an adhesiveegg producing fish is sufficient to induce changes in both egg adhesiveness and buoyancy in zebrafish,emphasizing the important role of zp genes in the regulation of spawning habits.Our results thus provide new insights into how endemic East Asian cyprinids may have adapted to the Yangtze river-lake system via changes in spawning habits.展开更多
Continuous monitoring of biosignals is essential for advancing early disease detection,personalized treatment,and health management.Flexible electronics,capable of accurately monitoring biosignals in daily life,have g...Continuous monitoring of biosignals is essential for advancing early disease detection,personalized treatment,and health management.Flexible electronics,capable of accurately monitoring biosignals in daily life,have garnered considerable attention due to their softness,conformability,and biocompatibility.However,several challenges remain,including imperfect skin-device interfaces,limited breathability,and insufficient mechanoelectrical stability.On-skin epidermal electronics,distinguished by their excellent conformability,breathability,and mechanoelectrical robustness,offer a promising solution for high-fidelity,long-term health monitoring.These devices can seamlessly integrate with the human body,leading to transformative advancements in future personalized healthcare.This review provides a systematic examination of recent advancements in on-skin epidermal electronics,with particular emphasis on critical aspects including material science,structural design,desired properties,and practical applications.We explore various materials,considering their properties and the corresponding structural designs developed to construct high-performance epidermal electronics.We then discuss different approaches for achieving the desired device properties necessary for long-term health monitoring,including adhesiveness,breathability,and mechanoelectrical stability.Additionally,we summarize the diverse applications of these devices in monitoring biophysical and physiological signals.Finally,we address the challenges facing these devices and outline future prospects,offering insights into the ongoing development of on-skin epidermal electronics for long-term health monitoring.展开更多
In view of the phenomenon that the adhesion strength between the surface of polyacrylonitrile-butadiene-styrene-polycarbonate(ABS-PC)copolymer and the electroless copper plating layer is relatively low.To solve the pr...In view of the phenomenon that the adhesion strength between the surface of polyacrylonitrile-butadiene-styrene-polycarbonate(ABS-PC)copolymer and the electroless copper plating layer is relatively low.To solve the problems of poor surface wettability and low surface roughness of the ABS-PC substrate,the N,N-dimethylformamide(DMF)-ethanol(C_(2)H_(5)OH)-water(H_(2)O)system was employed as the swelling system for the ABS-PC substrate.The effects of the DMF volume fraction in the swelling system and the swelling time on the swelling effect of ABS-PC at 35℃were investigated.KMnO_(4)-H_(2)SO_(4)-H_(2)O system was used as the etching system for ABS-PC substrate under the conditions of the volume ratio of water to sulfuric acid of 1﹕2,with KMnO_(4)content of 30 g/L,etching temperature of 60℃,and etching time of 25 min.The results indicate that dense pores with uniform sized are formed on the surface of the ABS-PC substrate surface after swelling and etching treatments,accompanied by an increase in surface roughness when the swelling temperature is 35℃,the DMF volume fraction in the swelling system is 80%,and the swelling time is 5 min.Furthermore,the content of C element on the surface of the ABS-PC substrate decreased,while that of O element increased,and the surface hydrophilicity is enhanced,which is attributed to two hydrophilic groups,-C=O and-COOH,being generated on the ABS-PC substrate surface,significantly improving the wettability of the ABS-PC substrate surface.Under the combination effects of high surface roughness and strong surface hydrophilicity,the adhesion strength between the ABS-PC substrate surface and the electroless copper plating layer reached to 0.81 kN/m,meeting the adhesion strength requirement of 0.70 kN/m in the industrial production.展开更多
The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely sole...The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely solely on a passive wrap-ping mechanism,limit their capacity to capture objects within a specific size range and make it challenging to handle unexpected situations.Inspired by spider webs,which combine wrapping and adhering to capture prey of various sizes,we present a new type of net(envelope diameter:208.49 mm)for on-orbit capture.This net adopts a spiral symmetric structure similar to spider webs,incorporates electrostatic-microstructure hybrid adhesives,and increases the maximum contact area by 38.31%,allowing it to capture debris ranging from fragments smaller than the mesh size(envelope diam-eter:2.7 mm-4.4 mm)to larger objects(envelope diameter:270 mm),and effectively grasps flexible items(450 mm2),planar items(350 mm2)and three-dimensional items(160 mm3).Moreover,to validate the net's capability for wrapping and adhesion,simulations and experiments are demonstrated that this dual capture method can effectively handle various targets.展开更多
The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging becaus...The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging because of the demanding requirements for high-precision instrumentation and complex calibration procedures.In this study,an integrated framework was presented that combined physical experiments,theoretical approaches,and machine learning to enable the autonomous determination of the shear adhesive strength of soil under multiple influencing factors.We developed an improved particle swarm optimization-optimized ordinary kriging(IPOK)surrogate testing method to enhance the limited experimental datasets,and a lightweight residual neural network(RLNet)was then used for effective intra-and extra-domain predictions.A comprehensive model discussion,comparison,and interpretability analysis were conducted.The results from 64 physical experiments considering the consistency index,normal stress,clay content,rotation rate,and disc material effectively characterized the shear adhesion behaviour of kaolin.The IPOK surrogate experiments successfully replicated the physical data points while enriching the dataset details.The RLNet model trained with IPOK data achieved superior prediction performance,with a root mean square error of 7.491 and a determination coefficient of 0.927 in 16 orthogonal validation tests,and high similarity was attained between the predicted and measured values.A detailed model discussion analysis confirmed the superiority of the IPOK-RLNet framework.This methodology provides a cost-effective rapid analysis technique for assessing clay‒metal interface shear adhesion,significantly reducing laboratory testing requirements and experimental costs while increasing engineering efficiency.展开更多
Natural evolution has endowed biological surfaces with unique microstructural features,enabling them to achieve complex functions such as grasping,climbing,and self-cleaning through precise regulation of adhesion.Insp...Natural evolution has endowed biological surfaces with unique microstructural features,enabling them to achieve complex functions such as grasping,climbing,and self-cleaning through precise regulation of adhesion.Inspired by this,bioinspired adhesive microstructures have shown tremendous application potential in the rapidly advancing and highly innovative biomedical field.This paper systematically reviews the adhesion systems of biological surfaces like those of geckos and tree frogs,and conducts an in-depth analysis of the adhesion mechanisms underlying various microstructures and their corresponding bioinspired adhesives from the critical perspective of structural characteristics.It reviews different types of interfacial adhesion models,with special emphasis on the suitability of the Cantor-Borodich profile model for accurately describing multiscale hierarchical adhesive structures in diverse and complex biological systems.The paper focuses on elaborating the significant contributions of bioinspired adhesives in biomedical engineering,particularly their practical and impactful applications in wearable medical devices such as stable adhesion in dynamic physiological environments,surgical instruments such as low-damage soft tissue gripping,and drug delivery systems such as enhanced transdermal delivery efficiency.Additionally,it outlines current development prospects and key challenges such as long-term biocompatibility,environmental adaptability,and structure-function synergistic optimization,providing new ideas and valuable references for further research and application of bioinspired adhesive microstructures in biomedical engineering.展开更多
As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been rep...As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been reported to promote the adhesion and biofilm formation of Shewanella spp.,but its role in adhesion and biofilm formation of S.putrefaciens under cold stress needs to be further investigated.To better comprehend the effect of BpfA on adhesion and biofilm formation of S.putrefaciens under cold stress(4℃),bacterial adhesion and biofilm phenotype of S.putrefaciens CN32 WT andΔbpfA at 4℃were analyzed and performed transcriptomics.The results showed that the deletion of bpfA had almost no effect on the growth of S.putrefaciens CN32 at 4℃,but weakened the unicellular adhesion capacity of S.putrefaciens CN32 and destabilized the stability of the multicellular adhesion layer.In addition,the biomass of the mature biofilm formed byΔbpfA was merely around 50%of that observed in the mature biofilm of S.putrefaciens CN32 WT,the average thickness and volume of the biofilm decreased by 18%and 27%,respectively,and the composition of the biofilm changed.Transcriptome analysis demonstrated that the deletion of bpfA led to differential expression of genes involved in metabolic pathways such as bacterial chemotaxis,two-component system,tyrosine metabolism,drug metabolism-other enzymes and biofilm formation-Vibrio cholerae,which in turn influenced bacterial adhesion and biofilm formation.Those results advance our acknowledgment of the character of BpfA on adhesion and biofilm formation of S.putrefaciens CN32,which contributes to understanding bacterial adhesion and the control of biofilm formation.展开更多
As a common electronic adhesive,ultraviolet(UV)curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane,excellent weather resistance and optical properties of acrylate.Despite the...As a common electronic adhesive,ultraviolet(UV)curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane,excellent weather resistance and optical properties of acrylate.Despite the extensive applications,it is still difficult to solve the problems caused by the shrinkage of adhesive.Here,a new type of photosensitive adhesive for bonding electronic components based on supramolecular interaction was designed and synthesized.The supramolecular interaction of cyclodextrin and adamantane moieties introduced into the adhesive polymer entitles the viscosity of the adhesive to rise rapidly during use,thereby preventing adhesive loss and dislocation of electronic components.UV light could further cure the adhesive and position the electronic components.The adhesive shrunk<2%when cured by UV light,so it can be used for electronic packaging and high-resolution,defect-free lithography.展开更多
We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels ar...We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels are both transparent and tough,with highly compacted networks.The hydrogels exhibit an ultimate tensile strength of approximately 4.55 MPa and a toughness of 160 MJ/m^(3).Additionally,the hydrogels adhere to a wide range of substrates,including metals,ceramics,glass,and even Teflon,with an adhesion strength of up to 42 kPa on Teflon plates.Given the biocompatibility and biodegradability of both PVA and TA,along with the hydrogels' toughness,transparency,and adhesiveness,we anticipated broad applications in the biomedical field,such as in articular cartilage restoration,electronic skin,and wound dressings.Additionally,these hydrogels hold significant potential for applications in wearable technology and optoelectronic devices.展开更多
Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containin...Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containing six animals:a sham group without peritoneal adhesion induction,a negative control group,and four intervention groups with both peritoneal adhesion induction and administration of 2 mL of vehicle or 0.1%,0.3%,1%,or 3%w/v P.granatum seed Soxhlet(PSS).Peritoneal adhesions were assessed through macroscopic examination,transforming growth factor-β1(TGF-β1),vascular endothelial growth factor(VEGF),and inflammatory cytokine tumor necrosis factor-α(TNF-α)levels were evaluated using biochemical methods.Results:The findings revealed no notable differences in adhesin scores between the therapeutic and negative control groups,but PSS(1 and 3%w/v)significantly reduced TNF-α,VEGF,and TGF-β1 levels compared with those in the negative control group(all P<.01).Conclusion:The results indicate that PSS is a potential treatment option for intraperitoneal adhesions.展开更多
Ionogel,a novel flexible electronic material,presents a plethora of applications.Despite its potential,the fabrication of multifunctional ionogel with high-performance suitable for diverse scenarios remains a signific...Ionogel,a novel flexible electronic material,presents a plethora of applications.Despite its potential,the fabrication of multifunctional ionogel with high-performance suitable for diverse scenarios remains a significant challenge.In this study,we prepare a multifunctional amphibious ionogel skin(AIGS)using a polymerizable ionic liquid(PIL)and a conductive ionic liquid(IL)in conjunction with titanium carbide(Ti_(3)C_(2)T_(x)-MXene).The resulting soft AIGS materials exhibit ductility,self-healing,and robust adhesion in mechanical properties due to non-covalent interactions,such as ion-dipole interactions and hydrogen bonding.They also demonstrate a wide sensing range(2%-400%),high sensing sensitivity(gauge factor(GF)up to 6.06),and stable sensing performance(good reliability and stability after strain)in electrical properties.The hydrophobic and dynamic viscoelastic network formed by extensive C-F bonds in the used polymer matrix,ensures the AIGS's suitability for amphibious environments.We find that AIGS has excellent triboelectric properties.Utilizing AIGS as a flexible electrode,a single-electrode triboelectric nanogenerator(SE-TENG)was constructed,achieving outstanding output performance(~300 V open-circuit voltage,172 nA short-circuit current,and 34 nC transferred charge).This device can power commercial portable electronic devices and identify different body movements.AIGS-based wearable strain sensors have also been shown to reliably detect human motion,including larger limb movements such as finger flexion and elbow flexion and extension,as well as subtle muscle movements such as frowning and swallowing.In addition,depending on the characteristics of the AIGS application in amphibious environments,the following functions can be realized simultaneously.AIGS in an aquatic environment combined with machine learning for intelligent recognition of breathing type,in an underwater environment combined with Morse code to convey simple information,and motion monitoring in an amphibious environment,demonstrates its potential feasibility in a variety of situations.展开更多
Concrete lining slabs of long-distance water conveyance projects in northern China are susceptible to freeze-thaw erosion,which places higher requirements on the performance of repair materials for eroded areas,such a...Concrete lining slabs of long-distance water conveyance projects in northern China are susceptible to freeze-thaw erosion,which places higher requirements on the performance of repair materials for eroded areas,such as frost resistance,adhesion,coating penetration depth,water absorption ratio,and durability.Performance tests were conducted on existing repair materials,and the results showed that:XYPEX exhibits better performance compared to other materials;the high-performance ultra-nano silane impregnant has outstanding performance;and the composite coating demonstrates excellent comprehensive performance.The composite material modified with nano-SiO_(2) has further improved strength and durability.展开更多
Silicone-based pressure-sensitive adhesives(Si-PSAs)are valued for their thermal stability,flexibility,and biocompatibility,but their weak bonding strength restricts high-performance use.Polyurethane-modified Si-PSAs ...Silicone-based pressure-sensitive adhesives(Si-PSAs)are valued for their thermal stability,flexibility,and biocompatibility,but their weak bonding strength restricts high-performance use.Polyurethane-modified Si-PSAs enhance adhesion,however diisocyanates remain essential.The raw materials of isocyanates are toxic,and their synthesis involves phosgene.To make up for those shortcomings,a series of poly(hydroxy urethane-siloxane)PSAs,named as PHUSi here,were synthesized through the ring-opening reaction of cyclic carbonate-functionalized polysiloxanes(PSi_(x)-VEC_(z))with various aliphatic diamines.The PSi_(x)-VEC_(z) precursors were prepared via the hydrosilylation of hydrogen-containing polysiloxanes(PSi_(x)-H_(y))with 4-vinyl-1,3-dioxolan-2-one(VEC).The chemical structures of PSi_(x)-H_(y),PSi_(x)-VEC_(z) and PHUSi were characterized,and bonding properties of PHUSi were systematically evaluated.The influence of architectures on adhesive performance was elucidated through comprehensive analyses,including rheology,crosslink density assessment,and so on.These studies revealed that the tailored design of PHUSi adhesives combine the advantages of traditional Si-PSAs with enhanced adhesion while eliminating isocyanate toxicity.The optimized PHUSi formulation achieved remarkable 180°peel strength(76.5 N/m on skin)and maximum probe tack force(1.61 N),enabling secure 24 h attachment of flexible sensors to skin.These properties make PHUSi particularly suitable for medical applications,as demonstrated by successful implementation in flexible electrocardiogram devices,offering a biocompatible,high-performance adhesive.展开更多
The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier t...The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier transform infrared spectroscopy,and ultra-depth microscope.The results show that the antibacterial adhesive can effectively inhibit the growth of sulfur-oxidizing bacteria in seawater,hinder their metabolism to produce biological sulfate,and reduce the formation of destructive product gypsum.The mineral composition and thermal analysis showed that the peak value of plaster diffraction peak and the mass loss of plaster dehydration in antibacterial adhesive group were significantly lower than those in blank group(without protective coating group).In addition,the electric flux of chloride ions(>400 C)in the blank group of mortar samples was higher than that in the antibacterial adhesive group(<200 C),indicating that the antibacterial adhesive can effectively reduce the permeability of chloride ions in mortar,and thus hinder the Cl-erosion in seawater.展开更多
Conductive cotton fabrics have emerged as promising platforms for advanced wearable applications,including strain sensing,electrical heating,and photothermal conversion.However,their widespread adoption is hindered by...Conductive cotton fabrics have emerged as promising platforms for advanced wearable applications,including strain sensing,electrical heating,and photothermal conversion.However,their widespread adoption is hindered by several critical limitations:dependence on petroleum-based materials,inherent hydrophilicity,and insufficient durability in practical environments.To overcome these challenges,an eco-friendly,mussel-inspired conductive coating system comprising tannic acid,cellulose nanofibers,and carbon nanotubes is developed.Through a facile dip-coating approach followed by in situ tannic acid polymerization-induced surface roughening and octadecylamine modification,a superhydrophobic conductive cotton fabric combining exceptional flexibility,breathability,and environmental stability is fabricated.The resulting superhydrophobic conductive cotton fabric demonstrates outstanding strain-sensing performance,featuring a rapid response time(127 ms)and reliable signal output over 4000 stretching cycles,capable of precisely detecting various human motions even underwater.Furthermore,the superhydrophobic conductive cotton fabric achieves impressive electrothermal(103.9℃at 15 V)and photothermal(104.2℃at 350 mW cm^(-2))conversion efficiencies with excellent temperature controllability.This multifunctional fabric presents a sustainable solution for next-generation wearable electronics and intelligent thermal management systems,addressing both environmental concerns and performance requirements for real-world applications.展开更多
This study explores the use of black soldier fly larvae protein as a bio-based adhesive to produce particleboards from sugarcane bagasse.A comprehensive evaluation was conducted,including rheological characterization ...This study explores the use of black soldier fly larvae protein as a bio-based adhesive to produce particleboards from sugarcane bagasse.A comprehensive evaluation was conducted,including rheological characterization of the adhesive and physical–mechanical testing of the panels according to European standards.The black soldier fly larvae-based adhesive exhibited gel-like viscoelastic behavior,rapid partial structural recovery after shear,and favorable application properties.Particleboards manufactured with this adhesive and sugarcane bagasse achieved promising mechanical performance,with modulus of rupture and modulus of elasticity values of 30.2 and 3500 MPa,respectively.Internal bond strength exceeded 0.4 MPa,complying with European standard 312-3 specifications.For comparative purposes,a panel made with Eucalyptus grandis particles was also produced under the same conditions to demonstrate the versatility of the adhesive system.Compared to other bio-based and synthetic adhesives,this bio-based system showed competitive performance and derives from the bioconversion of organic residues.Protein adhesives were synthesized fromHermetia illucens larvae grown commercially on agriculturalwaste frompotato chip production,emphasizing the renewable origin of both the biomass and the final adhesive.These results highlight the potential of insect proteins as sustainable and circular alternatives for the wood panel industry.展开更多
Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a si...Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a significant challenge.This study presents a numerical investigation of adhesively bonded joints with different adhesive properties using ultrasonic guided waves.The main focus of the investigation is to evaluate the feasibility of using guided waves to assess bond integrity,particularly for detecting challenging weak bonds.For this purpose,a theoretical analysis of dispersion curves was conducted,revealing that the S0 Lamb wave mode is significantly sensitive to variations in adhesive properties in the 300-700 kHz frequency range.Finite element modelling was used to analyse the propagation of guided waves in two scenarios:an adhesively bonded aluminum structure and a more complex configuration-adhesively bonded lap joints.The Short-Time Fourier Transform(STFT)was used to process the obtained results and determine the group velocities of guided waves.By analysing the group velocity characteristics,their dependence on the adhesive properties was identified.In the first scenario,a clear separation of S0 modes from A0 modes was observed in the STFT analysis,with a decrease in group velocity as adhesive stiffness increased.For the more complex lap joint scenario,the separation between A0 and S0 modes was less distinct.However,the analysis of the average group velocity shows a dependence of average group velocity on adhesive properties.This is similar to the first scenario.There is a decrease in average group velocity as adhesive stiffness increases.The results obtained demonstrate that guided wavebased methods have a high potential for non-destructive evaluation of adhesively bonded structures,including the detection of weak bonds.展开更多
The complex interactions and conflicting performance demands in multi-component composites pose significant challenges for achieving balanced multi-property optimization through conventional trial-and-error approaches...The complex interactions and conflicting performance demands in multi-component composites pose significant challenges for achieving balanced multi-property optimization through conventional trial-and-error approaches.Machine learning(ML)offers a promising solution,markedly improving materials discovery efficiency.However,the high dimensionality of feature spaces in such systems has long impeded effective ML-driven feature representation and inverse design.To overcome this,we present an Intelligent Screening System(ISS)framework to accelerate the discovery of optimal formulations balancing four key properties in 15-component PTFE-based copper-clad laminate composites(PTFE-CCLCs).ISS adopts modular descriptors based on the physical information of component volume fractions,thereby simplifying the feature representation.By leveraging the inverse prediction capability of ML models and constructing a performance-driven virtual candidate database,ISS significantly reduced the computational complexity associated with high-dimensional spaces.Experimental validation confirmed that ISSoptimized formulations exhibited superior synergy,notably resolving the trade-off between thermal conductivity and peel strength,and outperform many commercial counterparts.Despite limited data and inherent process variability,ISS achieved an average prediction accuracy of 76.5%,with thermal conductivity predictions exceeding 90%,demonstrating robust reliability.This work provides an innovative,efficient strategy for multifunctional optimization and accelerated discovery in ultra-complex composite systems,highlighting the integration of ML and advanced materials design.展开更多
Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short...Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short time remains a major challenge.In this study,a multifunctional mussel-inspired hydrogel was synthesized in only 5 min,with polydopamine(PDA)-polypyrrole(Ppy)-polyaniline(PANi)and poly(vinyl alcohol)(PVA)nanoparticles incorporated into the polyacrylamide(PAM)network.The resulting hydrogel exhibited high transparency(about 90% light transmission in the range of 400-800 nm),high conductivity((95.4±0.4)×10^(-4)S/cm),tensile strength(32.60±1.03 k Pa),strain at break(904.46%±11.50%),and adhesive strength(30-60 k Pa).It also demonstrated rapid self-healing properties(about 48% strength recovery within 1h at 50℃)and water-dependent shape memory behavior.As a wearable strain sensor,the hydrogel successfully detected finger flexion,wrist movements,facial expression changes,and breathing with high sensitivity and stability.The calculated gauge factor(GF)was 7.44±0.31,which is higher than that of many previously reported hydrogels.Compared with previous oyster-inspired or Ppy-based hydrogels,our system showed a much shorter synthesis time,higher transparency,and enhanced multifunctionality.These findings highlight the potential of the proposed hydrogel for next-generation flexible electronics,e-skin,and biomedical monitoring devices.展开更多
In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is c...In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is considered dynamic.The contact condition on the normal plane is modeled by a unilateral constraint condition for a version of normal velocity in which the memory effect and the adhesion are considered.On the tangential plane a frictional contact condition is governed by the Clarke subdifferential of a locally Lipschitz function,and the evolution of the bonding field is governed by an ordinary differential equation.We formulate this problem as coupled system that consists of two ordinary differential equations and a variational-hemivariational inequality.Then,the existence,uniqueness and continuous dependence of the solution on the data results concerning the abstract system are established.Finally,we use the abstract results to show the existence and uniqueness of the solution to the contact problem.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31000000)。
文摘Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We recently identified zona pellucida(Zp) as the top differentially expressed protein between East Asian cyprinids that produce adhesive and semi-buoyant eggs,suggesting that Zp protein may play important roles in the regulation of egg type.In this work,we generated transgenic zebrafish in which oocyte-specific expression of zp genes from rare minnow(Gobiocypris rarus),an East Asian cyprinid laying adhesive eggs,was driven by a zebrafish zp3.2 gene promoter.We found that the transgenic eggs obtained partial adhesiveness and exhibited alteration in hydration and buoyancy.Abnormal metabolism of vitellogenin(VTG) may contribute to enhanced hydration and/or buoyancy.Our work shows that expression of the exogenous zp3a gene from an adhesiveegg producing fish is sufficient to induce changes in both egg adhesiveness and buoyancy in zebrafish,emphasizing the important role of zp genes in the regulation of spawning habits.Our results thus provide new insights into how endemic East Asian cyprinids may have adapted to the Yangtze river-lake system via changes in spawning habits.
基金supported by National Natural Science Foundation of China(Grant Nos.52025055,52375576,52350349)Key Research and Development Program of Shaanxi(Program No.2022GXLH-01-12)+2 种基金Joint Fund of Ministry of Education for Equipment Pre-research(No.8091B03012304)Aeronautical Science Foundation of China(No.2022004607001)the Fundamental Research Funds for the Central Universities(No.xtr072024031).
文摘Continuous monitoring of biosignals is essential for advancing early disease detection,personalized treatment,and health management.Flexible electronics,capable of accurately monitoring biosignals in daily life,have garnered considerable attention due to their softness,conformability,and biocompatibility.However,several challenges remain,including imperfect skin-device interfaces,limited breathability,and insufficient mechanoelectrical stability.On-skin epidermal electronics,distinguished by their excellent conformability,breathability,and mechanoelectrical robustness,offer a promising solution for high-fidelity,long-term health monitoring.These devices can seamlessly integrate with the human body,leading to transformative advancements in future personalized healthcare.This review provides a systematic examination of recent advancements in on-skin epidermal electronics,with particular emphasis on critical aspects including material science,structural design,desired properties,and practical applications.We explore various materials,considering their properties and the corresponding structural designs developed to construct high-performance epidermal electronics.We then discuss different approaches for achieving the desired device properties necessary for long-term health monitoring,including adhesiveness,breathability,and mechanoelectrical stability.Additionally,we summarize the diverse applications of these devices in monitoring biophysical and physiological signals.Finally,we address the challenges facing these devices and outline future prospects,offering insights into the ongoing development of on-skin epidermal electronics for long-term health monitoring.
文摘In view of the phenomenon that the adhesion strength between the surface of polyacrylonitrile-butadiene-styrene-polycarbonate(ABS-PC)copolymer and the electroless copper plating layer is relatively low.To solve the problems of poor surface wettability and low surface roughness of the ABS-PC substrate,the N,N-dimethylformamide(DMF)-ethanol(C_(2)H_(5)OH)-water(H_(2)O)system was employed as the swelling system for the ABS-PC substrate.The effects of the DMF volume fraction in the swelling system and the swelling time on the swelling effect of ABS-PC at 35℃were investigated.KMnO_(4)-H_(2)SO_(4)-H_(2)O system was used as the etching system for ABS-PC substrate under the conditions of the volume ratio of water to sulfuric acid of 1﹕2,with KMnO_(4)content of 30 g/L,etching temperature of 60℃,and etching time of 25 min.The results indicate that dense pores with uniform sized are formed on the surface of the ABS-PC substrate surface after swelling and etching treatments,accompanied by an increase in surface roughness when the swelling temperature is 35℃,the DMF volume fraction in the swelling system is 80%,and the swelling time is 5 min.Furthermore,the content of C element on the surface of the ABS-PC substrate decreased,while that of O element increased,and the surface hydrophilicity is enhanced,which is attributed to two hydrophilic groups,-C=O and-COOH,being generated on the ABS-PC substrate surface,significantly improving the wettability of the ABS-PC substrate surface.Under the combination effects of high surface roughness and strong surface hydrophilicity,the adhesion strength between the ABS-PC substrate surface and the electroless copper plating layer reached to 0.81 kN/m,meeting the adhesion strength requirement of 0.70 kN/m in the industrial production.
基金the New Chongqing Innovative Young Talent Project under Grant 2024NSCQ-qncxX0468Dreams Foundation of Jianghuai Advance Technology Center under Grant 2023-ZM01Z007.
文摘The net capturing method holds great potential for space debris removal due to its adaptability to the various target shapes and high fault tolerance.However,the capture mechanisms of current rope nets,which rely solely on a passive wrap-ping mechanism,limit their capacity to capture objects within a specific size range and make it challenging to handle unexpected situations.Inspired by spider webs,which combine wrapping and adhering to capture prey of various sizes,we present a new type of net(envelope diameter:208.49 mm)for on-orbit capture.This net adopts a spiral symmetric structure similar to spider webs,incorporates electrostatic-microstructure hybrid adhesives,and increases the maximum contact area by 38.31%,allowing it to capture debris ranging from fragments smaller than the mesh size(envelope diam-eter:2.7 mm-4.4 mm)to larger objects(envelope diameter:270 mm),and effectively grasps flexible items(450 mm2),planar items(350 mm2)and three-dimensional items(160 mm3).Moreover,to validate the net's capability for wrapping and adhesion,simulations and experiments are demonstrated that this dual capture method can effectively handle various targets.
基金financial support pro-vided by National Natural Science Foundation of China(Grant No.52178402).
文摘The shear adhesive strength at the clay‒metal interfaces serves as a critical parameter for evaluating the soil adhesion and metal interface mudding phenomena.However,its rapid determination remains challenging because of the demanding requirements for high-precision instrumentation and complex calibration procedures.In this study,an integrated framework was presented that combined physical experiments,theoretical approaches,and machine learning to enable the autonomous determination of the shear adhesive strength of soil under multiple influencing factors.We developed an improved particle swarm optimization-optimized ordinary kriging(IPOK)surrogate testing method to enhance the limited experimental datasets,and a lightweight residual neural network(RLNet)was then used for effective intra-and extra-domain predictions.A comprehensive model discussion,comparison,and interpretability analysis were conducted.The results from 64 physical experiments considering the consistency index,normal stress,clay content,rotation rate,and disc material effectively characterized the shear adhesion behaviour of kaolin.The IPOK surrogate experiments successfully replicated the physical data points while enriching the dataset details.The RLNet model trained with IPOK data achieved superior prediction performance,with a root mean square error of 7.491 and a determination coefficient of 0.927 in 16 orthogonal validation tests,and high similarity was attained between the predicted and measured values.A detailed model discussion analysis confirmed the superiority of the IPOK-RLNet framework.This methodology provides a cost-effective rapid analysis technique for assessing clay‒metal interface shear adhesion,significantly reducing laboratory testing requirements and experimental costs while increasing engineering efficiency.
基金supported and funded by the National Natural Science Foundation of China(HWG2022001,12402135,52575201 and 12502114)the China Postdoctoral Science Foundation(2024M763860)support from Chongqing City Science and Technology Program(Grant No.CSTB2025NSCQ-GPX0760,CSTB2025NSCQ-GPX0778 and CSTB2025NSCQ-GPX0784).
文摘Natural evolution has endowed biological surfaces with unique microstructural features,enabling them to achieve complex functions such as grasping,climbing,and self-cleaning through precise regulation of adhesion.Inspired by this,bioinspired adhesive microstructures have shown tremendous application potential in the rapidly advancing and highly innovative biomedical field.This paper systematically reviews the adhesion systems of biological surfaces like those of geckos and tree frogs,and conducts an in-depth analysis of the adhesion mechanisms underlying various microstructures and their corresponding bioinspired adhesives from the critical perspective of structural characteristics.It reviews different types of interfacial adhesion models,with special emphasis on the suitability of the Cantor-Borodich profile model for accurately describing multiscale hierarchical adhesive structures in diverse and complex biological systems.The paper focuses on elaborating the significant contributions of bioinspired adhesives in biomedical engineering,particularly their practical and impactful applications in wearable medical devices such as stable adhesion in dynamic physiological environments,surgical instruments such as low-damage soft tissue gripping,and drug delivery systems such as enhanced transdermal delivery efficiency.Additionally,it outlines current development prospects and key challenges such as long-term biocompatibility,environmental adaptability,and structure-function synergistic optimization,providing new ideas and valuable references for further research and application of bioinspired adhesive microstructures in biomedical engineering.
基金funded by the National Natural Science Foundation of China(32472401).
文摘As a specific spoilage organism of seafood under refrigerated temperature conditions,Shewanella spp.tend to form biofilms that exacerbate the occurrence of seafood spoilage.Biofilm-promoting factor A(BpfA)has been reported to promote the adhesion and biofilm formation of Shewanella spp.,but its role in adhesion and biofilm formation of S.putrefaciens under cold stress needs to be further investigated.To better comprehend the effect of BpfA on adhesion and biofilm formation of S.putrefaciens under cold stress(4℃),bacterial adhesion and biofilm phenotype of S.putrefaciens CN32 WT andΔbpfA at 4℃were analyzed and performed transcriptomics.The results showed that the deletion of bpfA had almost no effect on the growth of S.putrefaciens CN32 at 4℃,but weakened the unicellular adhesion capacity of S.putrefaciens CN32 and destabilized the stability of the multicellular adhesion layer.In addition,the biomass of the mature biofilm formed byΔbpfA was merely around 50%of that observed in the mature biofilm of S.putrefaciens CN32 WT,the average thickness and volume of the biofilm decreased by 18%and 27%,respectively,and the composition of the biofilm changed.Transcriptome analysis demonstrated that the deletion of bpfA led to differential expression of genes involved in metabolic pathways such as bacterial chemotaxis,two-component system,tyrosine metabolism,drug metabolism-other enzymes and biofilm formation-Vibrio cholerae,which in turn influenced bacterial adhesion and biofilm formation.Those results advance our acknowledgment of the character of BpfA on adhesion and biofilm formation of S.putrefaciens CN32,which contributes to understanding bacterial adhesion and the control of biofilm formation.
基金support from the National Natural Science Foundation of China(No.22308279)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110695)Natural Science Foundation of Chongqing(No.2023NSCQMSX2773).
文摘As a common electronic adhesive,ultraviolet(UV)curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane,excellent weather resistance and optical properties of acrylate.Despite the extensive applications,it is still difficult to solve the problems caused by the shrinkage of adhesive.Here,a new type of photosensitive adhesive for bonding electronic components based on supramolecular interaction was designed and synthesized.The supramolecular interaction of cyclodextrin and adamantane moieties introduced into the adhesive polymer entitles the viscosity of the adhesive to rise rapidly during use,thereby preventing adhesive loss and dislocation of electronic components.UV light could further cure the adhesive and position the electronic components.The adhesive shrunk<2%when cured by UV light,so it can be used for electronic packaging and high-resolution,defect-free lithography.
基金Funded by the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030001)the National Key Research and Development Program of China(No. 2021YFB3802300)the National Natural Science Foundation of China(Nos. 52403153 and 52203169)。
文摘We proposed a strategy using high-concentration tannic acid(TA) solutions to form robust and dense supramolecular networks in hydrogels,driven by the high osmotic pressure of the TA solution.The resulting hydrogels are both transparent and tough,with highly compacted networks.The hydrogels exhibit an ultimate tensile strength of approximately 4.55 MPa and a toughness of 160 MJ/m^(3).Additionally,the hydrogels adhere to a wide range of substrates,including metals,ceramics,glass,and even Teflon,with an adhesion strength of up to 42 kPa on Teflon plates.Given the biocompatibility and biodegradability of both PVA and TA,along with the hydrogels' toughness,transparency,and adhesiveness,we anticipated broad applications in the biomedical field,such as in articular cartilage restoration,electronic skin,and wound dressings.Additionally,these hydrogels hold significant potential for applications in wearable technology and optoelectronic devices.
基金financially supported by Mashhad University of Medical Sciences(961726).
文摘Objective:To explore the effects of Punica granatum L.(P.granatum,Shi Liu)seed in the management of peritoneal adhesions(PAs)in rats.Methods:The mature male rats were separated into the following groups,each containing six animals:a sham group without peritoneal adhesion induction,a negative control group,and four intervention groups with both peritoneal adhesion induction and administration of 2 mL of vehicle or 0.1%,0.3%,1%,or 3%w/v P.granatum seed Soxhlet(PSS).Peritoneal adhesions were assessed through macroscopic examination,transforming growth factor-β1(TGF-β1),vascular endothelial growth factor(VEGF),and inflammatory cytokine tumor necrosis factor-α(TNF-α)levels were evaluated using biochemical methods.Results:The findings revealed no notable differences in adhesin scores between the therapeutic and negative control groups,but PSS(1 and 3%w/v)significantly reduced TNF-α,VEGF,and TGF-β1 levels compared with those in the negative control group(all P<.01).Conclusion:The results indicate that PSS is a potential treatment option for intraperitoneal adhesions.
基金Outstanding Talent in Tianjin(JC20230428)Young Scientific and Technological Talents(Level Three)in Tianjin(QN20230304)the National Key Research and Development Program of China(Grant Nos.AMMS-QNPY-2021-008,2021ZZKY02)。
文摘Ionogel,a novel flexible electronic material,presents a plethora of applications.Despite its potential,the fabrication of multifunctional ionogel with high-performance suitable for diverse scenarios remains a significant challenge.In this study,we prepare a multifunctional amphibious ionogel skin(AIGS)using a polymerizable ionic liquid(PIL)and a conductive ionic liquid(IL)in conjunction with titanium carbide(Ti_(3)C_(2)T_(x)-MXene).The resulting soft AIGS materials exhibit ductility,self-healing,and robust adhesion in mechanical properties due to non-covalent interactions,such as ion-dipole interactions and hydrogen bonding.They also demonstrate a wide sensing range(2%-400%),high sensing sensitivity(gauge factor(GF)up to 6.06),and stable sensing performance(good reliability and stability after strain)in electrical properties.The hydrophobic and dynamic viscoelastic network formed by extensive C-F bonds in the used polymer matrix,ensures the AIGS's suitability for amphibious environments.We find that AIGS has excellent triboelectric properties.Utilizing AIGS as a flexible electrode,a single-electrode triboelectric nanogenerator(SE-TENG)was constructed,achieving outstanding output performance(~300 V open-circuit voltage,172 nA short-circuit current,and 34 nC transferred charge).This device can power commercial portable electronic devices and identify different body movements.AIGS-based wearable strain sensors have also been shown to reliably detect human motion,including larger limb movements such as finger flexion and elbow flexion and extension,as well as subtle muscle movements such as frowning and swallowing.In addition,depending on the characteristics of the AIGS application in amphibious environments,the following functions can be realized simultaneously.AIGS in an aquatic environment combined with machine learning for intelligent recognition of breathing type,in an underwater environment combined with Morse code to convey simple information,and motion monitoring in an amphibious environment,demonstrates its potential feasibility in a variety of situations.
文摘Concrete lining slabs of long-distance water conveyance projects in northern China are susceptible to freeze-thaw erosion,which places higher requirements on the performance of repair materials for eroded areas,such as frost resistance,adhesion,coating penetration depth,water absorption ratio,and durability.Performance tests were conducted on existing repair materials,and the results showed that:XYPEX exhibits better performance compared to other materials;the high-performance ultra-nano silane impregnant has outstanding performance;and the composite coating demonstrates excellent comprehensive performance.The composite material modified with nano-SiO_(2) has further improved strength and durability.
基金financially supported by the Shandong Provincial Natural Science Foundation,China(Nos.ZR2022MB051 and ZR2021MB112)Postdoctoral Science Foundation of China(No.2022M712343)+2 种基金Jinan City University Integration Development Strategy Project(No.JNSX2024030)Key Laboratory of Special Functional Aggregates of the Ministry of Education,Shandong University(No.JJT-2023-02)Shandong SD-Link New Material Technology Co.,LTD.
文摘Silicone-based pressure-sensitive adhesives(Si-PSAs)are valued for their thermal stability,flexibility,and biocompatibility,but their weak bonding strength restricts high-performance use.Polyurethane-modified Si-PSAs enhance adhesion,however diisocyanates remain essential.The raw materials of isocyanates are toxic,and their synthesis involves phosgene.To make up for those shortcomings,a series of poly(hydroxy urethane-siloxane)PSAs,named as PHUSi here,were synthesized through the ring-opening reaction of cyclic carbonate-functionalized polysiloxanes(PSi_(x)-VEC_(z))with various aliphatic diamines.The PSi_(x)-VEC_(z) precursors were prepared via the hydrosilylation of hydrogen-containing polysiloxanes(PSi_(x)-H_(y))with 4-vinyl-1,3-dioxolan-2-one(VEC).The chemical structures of PSi_(x)-H_(y),PSi_(x)-VEC_(z) and PHUSi were characterized,and bonding properties of PHUSi were systematically evaluated.The influence of architectures on adhesive performance was elucidated through comprehensive analyses,including rheology,crosslink density assessment,and so on.These studies revealed that the tailored design of PHUSi adhesives combine the advantages of traditional Si-PSAs with enhanced adhesion while eliminating isocyanate toxicity.The optimized PHUSi formulation achieved remarkable 180°peel strength(76.5 N/m on skin)and maximum probe tack force(1.61 N),enabling secure 24 h attachment of flexible sensors to skin.These properties make PHUSi particularly suitable for medical applications,as demonstrated by successful implementation in flexible electrocardiogram devices,offering a biocompatible,high-performance adhesive.
基金Funded by the National Natural Science Foundation of China(Nos.52278269,52278268,52178264)Tianjin Outstanding Young Scholars Science Fund Project(No.22JCJQJC00020)Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00430)。
文摘The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier transform infrared spectroscopy,and ultra-depth microscope.The results show that the antibacterial adhesive can effectively inhibit the growth of sulfur-oxidizing bacteria in seawater,hinder their metabolism to produce biological sulfate,and reduce the formation of destructive product gypsum.The mineral composition and thermal analysis showed that the peak value of plaster diffraction peak and the mass loss of plaster dehydration in antibacterial adhesive group were significantly lower than those in blank group(without protective coating group).In addition,the electric flux of chloride ions(>400 C)in the blank group of mortar samples was higher than that in the antibacterial adhesive group(<200 C),indicating that the antibacterial adhesive can effectively reduce the permeability of chloride ions in mortar,and thus hinder the Cl-erosion in seawater.
基金Fundamental Research Funds for the Central Universities(SWU-XDJH202314).
文摘Conductive cotton fabrics have emerged as promising platforms for advanced wearable applications,including strain sensing,electrical heating,and photothermal conversion.However,their widespread adoption is hindered by several critical limitations:dependence on petroleum-based materials,inherent hydrophilicity,and insufficient durability in practical environments.To overcome these challenges,an eco-friendly,mussel-inspired conductive coating system comprising tannic acid,cellulose nanofibers,and carbon nanotubes is developed.Through a facile dip-coating approach followed by in situ tannic acid polymerization-induced surface roughening and octadecylamine modification,a superhydrophobic conductive cotton fabric combining exceptional flexibility,breathability,and environmental stability is fabricated.The resulting superhydrophobic conductive cotton fabric demonstrates outstanding strain-sensing performance,featuring a rapid response time(127 ms)and reliable signal output over 4000 stretching cycles,capable of precisely detecting various human motions even underwater.Furthermore,the superhydrophobic conductive cotton fabric achieves impressive electrothermal(103.9℃at 15 V)and photothermal(104.2℃at 350 mW cm^(-2))conversion efficiencies with excellent temperature controllability.This multifunctional fabric presents a sustainable solution for next-generation wearable electronics and intelligent thermal management systems,addressing both environmental concerns and performance requirements for real-world applications.
基金supported by the Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)via grant Proyectos de Investigacion Plurianuales(PIP 2021:2894)Agencia I+D+i via grant Proyectos de Investigacion Cientifica y Tecnologica(PICT-2021-I-A-00294).
文摘This study explores the use of black soldier fly larvae protein as a bio-based adhesive to produce particleboards from sugarcane bagasse.A comprehensive evaluation was conducted,including rheological characterization of the adhesive and physical–mechanical testing of the panels according to European standards.The black soldier fly larvae-based adhesive exhibited gel-like viscoelastic behavior,rapid partial structural recovery after shear,and favorable application properties.Particleboards manufactured with this adhesive and sugarcane bagasse achieved promising mechanical performance,with modulus of rupture and modulus of elasticity values of 30.2 and 3500 MPa,respectively.Internal bond strength exceeded 0.4 MPa,complying with European standard 312-3 specifications.For comparative purposes,a panel made with Eucalyptus grandis particles was also produced under the same conditions to demonstrate the versatility of the adhesive system.Compared to other bio-based and synthetic adhesives,this bio-based system showed competitive performance and derives from the bioconversion of organic residues.Protein adhesives were synthesized fromHermetia illucens larvae grown commercially on agriculturalwaste frompotato chip production,emphasizing the renewable origin of both the biomass and the final adhesive.These results highlight the potential of insect proteins as sustainable and circular alternatives for the wood panel industry.
基金supported by the Research Council of Lithuania(LMTLT),agreement no.S-MIP-22-5.
文摘Adhesively bonded joints are widely used in modern lightweight structures due to their high strengthto-weight ratio and design flexibility.However,the reliable non-destructive evaluation of bond integrity remains a significant challenge.This study presents a numerical investigation of adhesively bonded joints with different adhesive properties using ultrasonic guided waves.The main focus of the investigation is to evaluate the feasibility of using guided waves to assess bond integrity,particularly for detecting challenging weak bonds.For this purpose,a theoretical analysis of dispersion curves was conducted,revealing that the S0 Lamb wave mode is significantly sensitive to variations in adhesive properties in the 300-700 kHz frequency range.Finite element modelling was used to analyse the propagation of guided waves in two scenarios:an adhesively bonded aluminum structure and a more complex configuration-adhesively bonded lap joints.The Short-Time Fourier Transform(STFT)was used to process the obtained results and determine the group velocities of guided waves.By analysing the group velocity characteristics,their dependence on the adhesive properties was identified.In the first scenario,a clear separation of S0 modes from A0 modes was observed in the STFT analysis,with a decrease in group velocity as adhesive stiffness increased.For the more complex lap joint scenario,the separation between A0 and S0 modes was less distinct.However,the analysis of the average group velocity shows a dependence of average group velocity on adhesive properties.This is similar to the first scenario.There is a decrease in average group velocity as adhesive stiffness increases.The results obtained demonstrate that guided wavebased methods have a high potential for non-destructive evaluation of adhesively bonded structures,including the detection of weak bonds.
基金financially supported by the National Key Research and Development Project of China(No.2022YFB3806900)。
文摘The complex interactions and conflicting performance demands in multi-component composites pose significant challenges for achieving balanced multi-property optimization through conventional trial-and-error approaches.Machine learning(ML)offers a promising solution,markedly improving materials discovery efficiency.However,the high dimensionality of feature spaces in such systems has long impeded effective ML-driven feature representation and inverse design.To overcome this,we present an Intelligent Screening System(ISS)framework to accelerate the discovery of optimal formulations balancing four key properties in 15-component PTFE-based copper-clad laminate composites(PTFE-CCLCs).ISS adopts modular descriptors based on the physical information of component volume fractions,thereby simplifying the feature representation.By leveraging the inverse prediction capability of ML models and constructing a performance-driven virtual candidate database,ISS significantly reduced the computational complexity associated with high-dimensional spaces.Experimental validation confirmed that ISSoptimized formulations exhibited superior synergy,notably resolving the trade-off between thermal conductivity and peel strength,and outperform many commercial counterparts.Despite limited data and inherent process variability,ISS achieved an average prediction accuracy of 76.5%,with thermal conductivity predictions exceeding 90%,demonstrating robust reliability.This work provides an innovative,efficient strategy for multifunctional optimization and accelerated discovery in ultra-complex composite systems,highlighting the integration of ML and advanced materials design.
文摘Conducting hydrogels have garnered significant interest in the field of wearable electronics.However,simultaneously achieving high transparency,high conductivity,strong adhesion,and self-healing ability within a short time remains a major challenge.In this study,a multifunctional mussel-inspired hydrogel was synthesized in only 5 min,with polydopamine(PDA)-polypyrrole(Ppy)-polyaniline(PANi)and poly(vinyl alcohol)(PVA)nanoparticles incorporated into the polyacrylamide(PAM)network.The resulting hydrogel exhibited high transparency(about 90% light transmission in the range of 400-800 nm),high conductivity((95.4±0.4)×10^(-4)S/cm),tensile strength(32.60±1.03 k Pa),strain at break(904.46%±11.50%),and adhesive strength(30-60 k Pa).It also demonstrated rapid self-healing properties(about 48% strength recovery within 1h at 50℃)and water-dependent shape memory behavior.As a wearable strain sensor,the hydrogel successfully detected finger flexion,wrist movements,facial expression changes,and breathing with high sensitivity and stability.The calculated gauge factor(GF)was 7.44±0.31,which is higher than that of many previously reported hydrogels.Compared with previous oyster-inspired or Ppy-based hydrogels,our system showed a much shorter synthesis time,higher transparency,and enhanced multifunctionality.These findings highlight the potential of the proposed hydrogel for next-generation flexible electronics,e-skin,and biomedical monitoring devices.
基金supported by the NSF of Shanxi(202303021221168)the Industry-university-research project of Shanxi Datong University(2022CXY10,2022CXY13).
文摘In this paper,our main goal is to study a new mathematical model which describes the frictional contact between a foundation and a deformable body which is composed of viscoplastic materials and where the process is considered dynamic.The contact condition on the normal plane is modeled by a unilateral constraint condition for a version of normal velocity in which the memory effect and the adhesion are considered.On the tangential plane a frictional contact condition is governed by the Clarke subdifferential of a locally Lipschitz function,and the evolution of the bonding field is governed by an ordinary differential equation.We formulate this problem as coupled system that consists of two ordinary differential equations and a variational-hemivariational inequality.Then,the existence,uniqueness and continuous dependence of the solution on the data results concerning the abstract system are established.Finally,we use the abstract results to show the existence and uniqueness of the solution to the contact problem.
