Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulat...Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulations.In this study,we investigated the dynamic behavior of sand particles during a vibratory sand-laying process for multi-material additive manufacturing using discrete element simulations.The objective is to enable precise control over the amount and distribution of sand for multi-material printing.In this study,we combined experiments and simulations to calibrate the contact parameters of different sands and establish a relationship between the curing agent content and surface energy of sand particles.A model for the vibratory fall of multimaterial sand was developed to study the motion characteristics of sand particles.This allows for macro-control over the sand spreading flow and high-quality multi-material sand laying.The results show that the flow rate of falling sand increases with decreasing surface energy of the particles,wider spreader openings,and higher vibration frequencies.For silica and chromite sands,when their surface energy ranged from 0.15 to 25 J·m^(2)and0.01-0.03 J·m^(2),respectively,and the sand spreader opening was 6 mm with a vibration frequency of 500 Hz,the sand flow rates of both materials became nearly identical.However,a higher sand paving speed and height increased the scattering of sand particles outside the target area,thereby decreasing the paving quality.The results accomplished in this study enable precise and uniform sand particle deposition and offers guidelines for optimizing sand speed and height,thus expanding the application of multi-material sand 3D printing in complex and high-performance manufacturing.展开更多
In order to mimic the natural heterogeneity of native tissue and provide a better microenvironment for cell culturing,multi-material bioprinting has become a common solution to construct tissue models in vitro.With th...In order to mimic the natural heterogeneity of native tissue and provide a better microenvironment for cell culturing,multi-material bioprinting has become a common solution to construct tissue models in vitro.With the embedded printing method,complex 3D structure can be printed using soft biomaterials with reasonable shape fidelity.However,the current sequential multi-material embedded printing method faces a major challenge,which is the inevitable trade-off between the printed structural integrity and printing precision.Here,we propose a simultaneous multi-material embedded printing method.With this method,we can easily print firmly attached and high-precision multilayer structures.With multiple individually controlled nozzles,different biomaterials can be precisely deposited into a single crevasse,minimizing uncontrolled squeezing and guarantees no contamination of embedding medium within the structure.We analyse the dynamics of the extruded bioink in the embedding medium both analytically and experimentally,and quantitatively evaluate the effects of printing parameters including printing speed and rheology of embedding medium,on the 3D morphology of the printed filament.We demonstrate the printing of double-layer thin-walled structures,each layer less than 200μm,as well as intestine and liver models with 5%gelatin methacryloyl that are crosslinked and extracted from the embedding medium without significant impairment or delamination.The peeling test further proves that the proposed method offers better structural integrity than conventional sequential printing methods.The proposed simultaneous multi-material embedded printing method can serve as a powerful tool to support the complex heterogeneous structure fabrication and open unique prospects for personalized medicine.展开更多
Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning o...Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning of inorganic functional materials have been developed,they operate at small scale and require long processing times,restricting their effective translation from laboratory to market.Here we report a fast,liquid-free,cost-effective,and environmentally friendly aerosol-based printing method for fabricating linear or planar structures at microscale dimensions.In situ and on-demand generation of dry aerosol via pulsed laser ablation,coupled with real-time aerodynamical focusing using a co-flowing sheath gas,allows the deposition of a wide variety of materials on various substrates at room temperature and atmospheric pressure.Using silver as a test material,we systematically characterized the laser-generated aerosol deposits in terms of microstructural morphology,sintering activity,mass yield,density,and electrical performance,to show the relationship between process variability and underlying mechanisms.The capacity of high-throughput printing of silver deposits,with thickness up to 160μm,in a single pass was demonstrated.This rapid,efficient,and inkless printing process opens new and exciting opportunities for future applications that require easy-to-integrate components in printed electronic devices.展开更多
Multi-material 3D fabrication at the nanoscale has been a long-sought goal in additive manufacturing,with great potential for the direct construction of functional micro/nanosystems rather than just arbitrary 3D struc...Multi-material 3D fabrication at the nanoscale has been a long-sought goal in additive manufacturing,with great potential for the direct construction of functional micro/nanosystems rather than just arbitrary 3D structures.To achieve this goal,researchers have introduced several nanoscale 3D printing principles,explored various multi-material switching and combination strategies,and demonstrated their potential applications in 3D integrated circuits,optoelectronics,biological devices,micro/nanorobots,etc.Although some progress has been made,it is still at the primary stage,and a serious breakthrough is needed to directly construct functional micro/nano systems.In this perspective,the development,current status and prospects of multi-material 3D nanoprinting are presented.We envision that this 3D printing will unlock innovative solutions and make significant contributions to various technologies and industries in the near future.展开更多
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ...Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.展开更多
The stress minimization multi-material topology optimization(MMTO)approach has recently attracted significant attention because of its applications in aerospace and mechanical engineering.Nonetheless,the stress minimi...The stress minimization multi-material topology optimization(MMTO)approach has recently attracted significant attention because of its applications in aerospace and mechanical engineering.Nonetheless,the stress minimization MMTO approach may result in stress surpassing the material's tolerance limit,potentially culminating in failure.This research proposes a novel way for imposing stress constraints on each material to regulate their respective stress levels.The fundamental concept is that each material possesses its own interpolation function for the stress model.The maximum von Mises stress for each material can be established with the definition of an upper limit,ensuring that the materials will perform safely and effectively.This aids topological structures in resisting failure and augmenting strength.A multi-physics system including thermoelastic and self-weight loads is concurrently examined alongside stress limitations.The global stress constraint utilizes the p-norm function,and the adjoint method is used to derive sensitivity.This work employs a three-field strategy utilizing density filtering and Heaviside projection functions to mitigate the artificial stress in low density.The technique is assessed through two-dimensional(2D)and three-dimensional(3D)examples,illustrating the influence of stress limits on the compliance minimization under heat and self-weight loads.The optimized results indicate a substantial decrease in the stress levels accompanied by a minor gain in compliance,while maintaining the stress within the specified range for all materials.展开更多
Integrating inorganic fillers into polymer-based 3D printing filaments is an effective strategy for improving thermal conduction but often compromises mechanical properties.In this study,we introduced electrospun poly...Integrating inorganic fillers into polymer-based 3D printing filaments is an effective strategy for improving thermal conduction but often compromises mechanical properties.In this study,we introduced electrospun polymer nanofibers(NF)into thermoplastic polyurethane(TPU)filaments alongside a ceramic filler,boron nitride(BN).By combining these organic(NF)and inorganic(BN)fillers,we created a dual-filler filament(TPU/BN/NF)that exhibited enhanced thermal conduction pathways without sacrificing the mechanical strength and electrical insulation.Comprehensive characterization demonstrated that BN improved heat transport,while a small fraction of electrospun NF effectively modulated the tensile modulus and partially recovered the strength lost upon BN addition.Finite element simulations further elucidated the influence of the nanofiber content,orientation,and length-to-diameter ratio on the mechanical performance.Notably,the dual-filler filaments retained good printability in standard fused deposition modeling(FDM)systems at optimized temperatures(about 210??℃).These findings offer a scalable approach for engineer multifunctional 3D printing filaments for 3D-printed thermal management products that require both thermal conduction performance and high insulation.展开更多
Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted dru...Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted drug delivery.For implants,mechanical properties are key performance characteristics,so understanding the deformation and failure mechanisms is essential for selecting the appropriate implant structure.The deformation and fracture processes in PLA samples with different interior architectures have been studied through computer simulation and experimental research.Two TPMS topologies,the Schwarz Diamond and Gyroid architectures,were used for the sample construction by 3D printing.ANSYS software was utilized to simulate compressive deformation.It was found that under the same load,the vonMises stresses in the Gyroid structure are higher than those in the Schwartz Diamond structure,which was associated with the different orientations of the cells in the studied structures in relation to the direction of the loading axis.The deformation process occurs in the local regions of the studied TPMS structures.Maximum von Mises stresses were observed in the vertical parts of the structures oriented along the load direction.It was found that,unlike the Gyroid,the Schwartz Diamond structure contains a frame that forms unique stiffening ribs,which ensures the redistribution of the load under the vertical loading direction.An analysis of the mechanical characteristics of PLA samples with the Schwartz Diamond and Gyroid structures produced by the Fused Deposition Modeling(FDM)method was correlated with computer simulation.The Schwarz Diamond-type structure was shown to have a higher absorption energy than the Gyroid one.A study of the fracture in PLA samples with various cell sizes revealed a particular feature related to the samples’periodic surface topology and the 3D printing process.Scanning electron microscopic(SEM)studies of the samples deformed by compression showed thatwith an increase in the density of the samples,the failure mechanism changes from ductile to quasi-brittle due to the complex participation of both cell deformation and fiber deformation.展开更多
Most failures in component operation occur due to cyclic loads.Validation has been performed under quasistatic loads,but the fatigue life of components under dynamic loads should be predicted to prevent failures durin...Most failures in component operation occur due to cyclic loads.Validation has been performed under quasistatic loads,but the fatigue life of components under dynamic loads should be predicted to prevent failures during component service life.Fatigue is a damage accumulation process where loads degrade the material,depending on the characteristics and number of repetitions of the load.Studies on themechanical fatigue of 3D-printedOnyx are limited.In this paper,the strength of 3D-printed Onyx components under dynamic conditions(repetitive loads)is estimated.Fatigue life prediction is influenced bymanufacturing processes,material properties,and applied loads,which can cause scatter in the results due to the interplay of these factors.By utilizing synthetic parameters derived from mechanical properties,the accuracy of fatigue life predictions has been improved significantly,from 23.13%to 98.33%.Additive manufacturing is flexible,but this flexibility generates scatter in the mechanical properties of produced components.This work also proposes the use of synthetic data with a neural network to improve the fatigue life prediction of printedOnyx subjected to tension–tension loads.Experimental uniaxial loads were used to characterize themechanical behaviorofprinted specimens.The experimental datawereused to evaluate thenumerical predictionsobtainedthrough finite element analysis using commercial software and an artificial neural network.The results showed that the use of synthetic data helped improve fatigue life prediction.展开更多
Electrochemical liquid lithium extraction technology has attracted much attention because of its high selectivity,good efficiency,and eco-friendliness.However,the low energy density per unit area and poor stability of...Electrochemical liquid lithium extraction technology has attracted much attention because of its high selectivity,good efficiency,and eco-friendliness.However,the low energy density per unit area and poor stability of traditional thin film electrodes(F-LMO),as well as manganese dissolution loss induced by the Jahn-Teller distortion of LiMn_(2)O_(4),hinder their industrial scalability.Herein,a durable and high-efficiency multistage porous LiMn_(2)O_(4) thick electrode was prepared sustainably by 3D printing technology(3DPLMO)for enhancing lithium recovery from salt lake brine.The multistage porous structure reduced the mass transfer resistance and shortened the ion diffusion path,which was conducive to accelerating the diffusion rate of Li+.Simultaneously,the three-dimensional conductive networks composed of reduced graphene oxide(r GO)and carbon nanotubes(CNT)synergized with the multistage pores effectively weakened the polarization phenomenon of the electrode and improved the stability of 3DP-LMO.The3DP-LMO exhibited a 5.5-fold higher extraction capacity per unit area and the Mn dissolution loss rate was only 1/15 compared with the F-LMO.Notably,the capacity retention rate of 3DP-LMO was 87.6%,significantly better than that of F-LMO(66.3%).Based on the quasi-in situ X-ray Diffraction results,the mechanism of lithium intercalation and deintercalation in 3DP-LMO was elucidated.Furthermore,lithium extraction parameters were optimized using response surface method-center composite design(RSM-CCD),resulting in an increase in lithium extraction capacity to 15.66 mg g^(-1)and a reduction in energy consumption to only 12.33 Wh mol^(-1).The results show that 3DP-LMO has significantly improved lithium extraction performance and stability,and has considerable prospects in practical application.展开更多
Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has bee...Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has been significant progress in enhancing photovoltaic performance,obvious stability problems remain a primary challenge that continues to hinder the commercial viability of PSCs.This present review first comprehensively discusses the main challenges to the commercialization of PSCs,including stability problems,ion migration,toxicity,and complexities in large-scale fabrication.It then effectively presents universal strategies to overcome the mentioned problems.Moreover,this review article examines various printing techniques that can be used to improve PSCs,emphasizing their benefits like low-cost components and procedures.Several printing processes are covered in the discussion,such as slot-die coating,spray coating,inkjet printing,doctor-blade coating,roll-to-roll printing,and screen printing.The potential uses of PSCs for the implementation of greenhouses,building-integrated photovoltaic systems,and indoor light energy harvesting.These uses highlight the adaptability of PSCs and demonstrate their ability to transform energy production technologies.Additionally,this review highlights the special qualities of perovskite materials that present chances to surpass silicon solar cells'efficiency restrictions and get close to the Shockley-Queisser limit.In conclusion,the current review provides a brief overview of recent developments,existing challenges,and opportunities of PSCs.It provides a thorough understanding of the merits of highly efficient PSCs fabricated by adopting printing methods to tackle stability problems along with facile fabrication of PSCs using simplified and cost-effective strategies.展开更多
Gradient refractive index(GRIN)metalenses are increasingly valued in high-frequency communication due to their exceptional radiation performance.Ceramics with high dielectric constants and low dielectric losses are id...Gradient refractive index(GRIN)metalenses are increasingly valued in high-frequency communication due to their exceptional radiation performance.Ceramics with high dielectric constants and low dielectric losses are ideal candidates for GRIN metalenses.Digital light processing(DLP)3D printing provides a feasible and efficient approach for manufacturing ceramic GRIN metalenses.However,the scattering of ultraviolet(UV)light by ceramic particles in the slurry reduces the printing accuracy of DLP technology,making it difficult to achieve the intricate structural features required for GRIN metalenses in high-frequency communication.In this work,we propose an approach to improve printing accuracy by optimizing the ceramic slurry composition and implementing a dimensional compensation design strategy.Utilizing geometric optics and the S-parameter inversion method,we design a GRIN metalens consisting of two distinct types of subwavelength unit cells(Y-shaped and circular hole geometries)with a minimum feature size of 160μm.Through a refined slurry formulation and precise design parameter compensation,high-fidelity ceramic GRIN metalenses are successfully fabricated.The fabricated metalens exhibits a maximum gain enhancement of 18.4 dBi and a deflection angle of±30°over a bandwidth of 37.84% in the W-band(75-110 GHz).The highly directional far-field beam radiation and efficient beam steering capabilities highlight the potential of ceramic GRIN metalenses for applications in satellite communications,radar systems,and other high-frequency technologies.展开更多
3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make i...3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems.展开更多
As bacterial infections have emerged as the second leading cause of death worldwide,the urgent demand for novel and effective antibacterial therapies continues to escalate.In this context,three-dimensional(3D)printing...As bacterial infections have emerged as the second leading cause of death worldwide,the urgent demand for novel and effective antibacterial therapies continues to escalate.In this context,three-dimensional(3D)printing technology offers transformative potential for the design and fabrication of oral formulations,internal implants,and external dressings in the management of bacterial inflammation.Conventional oral antibacterial agents often suffer from limitations in drug release kinetics and gastrointestinal stability.Leveraging 3D printing enables precise control over drug release profiles,thereby enhancing both bioavailability and therapeutic efficacy.Moreover,the development of internal implants requires high levels of individual specificity and structural precision.Through patient-specific customization and the incorporation of appropriate antibacterial materials,3D printing allows the fabrication of implants tailored to individual clinical needs,ultimately increasing surgical success rates and minimizing postoperative infection risks.Additionally,3D-printed external dressings exhibit excellent antibacterial activity,accelerate wound healing,and facilitate patient recovery.This review summarizes the fabrication methods,key advantages,and therapeutic outcomes of 3D printing in oral delivery systems,implantable devices,and wound dressings.It further highlights recent advances and emerging trends,offering insights and strategic guidance for the rational design and application of antibacterial therapeutics.展开更多
This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lacti...This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lactic acid)/thermoplastic polyurethane(PLA/TPU)matrix.Specifically,using a 70 wt%/30 wt%PLA/TPU matrix and an L_(9)(3^(2))orthogonal design,composites were evaluated via morphology,shape memory,mechanical tests,and multi-criteria analysis.Moderate DCP enhanced crosslinking,improving storage modulus and thermal stability,while excessive DCP caused brittleness.Furthermore,MAH-g-PE effectively improved interfacial compatibility,and its synergy with DCP was dosage-dependent.Consequently,Sample 5 achieved optimal performance,exhibiting uniform fracture morphology,a shape fixation rate of98.8%with the fastest recovery,and balanced strength-ductility.Multi-criteria analysis identified elongation at break and recovery time as the top contributing factors,with consistent rankings validated by Spearman analysis(ρ=0.833,p<0.01).In summary,adjusting DCP and MAH-g-PE contents effectively modulates the crosslinking structure and interfacial properties of PLA/TPU composites,providing a viable strategy for developing high-performance,tunable 4D printing materials.展开更多
Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability...Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability of the triazine ring structure within cyanate ester(CE)crosslinked networks after molding posed significant challenges for both recycling,repairing,and degradation of resin.To address these obstacles,dynamic thiocyanate ester(TCE)bonds and photocurable group were incorporated into CE,obtaining the recyclable and 3D printable CE covalent adaptable networks(CANs),denoted as PTCE1.5.This material exhibits a Young's modulus of 810 MPa and a tensile strength of 50.8 MPa.Notably,damaged printed PTCE1.5 objects can be readily repaired through reprinting and interface rejoining by thermal treatment.Leveraging the solid-state plasticity,PTCE1.5 also demonstrated attractive shape memory ability and permanent shape reconfigurability,enabling its reconfigurable 4D printing.The printed PTCE1.5 hinges and a main body were assembled into a deployable and retractable satellite model,validating its potential application as a controllable component in the aerospace field.Moreover,printed PTCE1.5 can be fully degraded into thiol-modified intermediate products.Overall,this material not only enriches the application range of CE resin,but also provides a reliable approach to addressing environmental issue.展开更多
Cell engineering is transitioning from“making cells express products”to“directly manufacturing functional structures inside cells.”This perspective outlines two-photon polymerization(TPP)-based direct writing of p...Cell engineering is transitioning from“making cells express products”to“directly manufacturing functional structures inside cells.”This perspective outlines two-photon polymerization(TPP)-based direct writing of polymerizable biocompatible materials to enable programmable micron-scale three-dimensional(3 D)functional architectures within living cells,thereby overcoming the limitations of simple endocytosis or phagocytosis.We highlight scalable workflows that couple bulk intracellular loading of biocompatible photoresists with automated TPP writing,and discuss how end ogenous proteins,biocompatible monomers,or biomate rials can be incorporated into these platforms as crosslinking elements to mitigate immune rejection and toxicity.This paradigm elevates the cell from a mere reaction vessel to an active factory,with direct implications for in vivo sensing,tracking,and precision drug delivery.However,key challenges remain,including establishing standardized material libraries,implementing autofocus and pose-adaptive control,and co-designing device architectures together with cellular functions.We anticipate that“intracellular 3 D printing”will provide a novel interface between synthetic biology and micro/nano-fabrication.展开更多
Sand mold 3 D printing technology is an advanced manufacturing technology which has great flexible manufacturing ability. A multi-material composite sand mold can control the temperature field of metallic parts during...Sand mold 3 D printing technology is an advanced manufacturing technology which has great flexible manufacturing ability. A multi-material composite sand mold can control the temperature field of metallic parts during the pouring process, while the current sand mold 3 D printing technology can only fabricate a single material sand mold. The casting temperature field can not be adjusted by using single sand mold material with isotropous heat exchange ability during the pouring process. In this work, a kind of novel coating device was designed. Multi-material composite sand molds could be manufactured using the coating device according to the casting process demands of the final parts. The influences of curing agent content, coating velocity and scraper shape on compactness and surface roughness of the sand layer(silica sand and zircon sand) were studied. The shapes and sizes of transition intervals of two kinds of sand granules were also tested. The results show that, with the increase of the added volume of curing agent, the compactness of sand layer reduces and the surface roughness value rises. With the increase of the velocity of the coating device, the compactness of sand layer reduces and the surface roughness value rises similarly. In addition, the scraper with a dip angle of 72 degrees could increase the compactness value of the sand layer. The criteria of quality parmeters of the coating procedure are obtained. That is, the surface roughness(δ) of sand layer should be equal to or lesser than half of main size of the sand particles(Dm). The parameter H of the coating device which is the distance between the base of hopper and the surface of sand layer impacts the size of transition zone. The width of the transition zone is in direct proportion to the parameter H, qualitatively. Through the optimization of the coating device, high quality of multi-material sand layers can be obtained. This will provide a solution in manufacturing the multi-material composite sand mold.展开更多
Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite t...Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.展开更多
As surgical procedures transition from conventional resection to advanced tissue-regeneration technologies,human disease therapy has witnessed a great leap forward.In particular,three-dimensional(3D)bioprinting stands...As surgical procedures transition from conventional resection to advanced tissue-regeneration technologies,human disease therapy has witnessed a great leap forward.In particular,three-dimensional(3D)bioprinting stands as a landmark in this setting,by promising the precise integration of biomaterials,cells,and bioactive molecules,thus opening up a novel avenue for tissue/organ regeneration.Curated by the editorial board of Bio-Design and Manufacturing,this review brings together a cohort of leading young scientists in China to dissect the core functionalities and evolutionary trajectory of 3D bioprinting,by elucidating the intricate challenges encountered in the manufacturing of transplantable organs.We further delve into the translational pathway from scientific research to clinical application,emphasizing the imperativeness of establishing a regulatory framework and rigorously enforcing quality-control measures.Finally,this review outlines the strategic landscape and innovative achievements of China in this field and provides a comprehensive roadmap for researchers worldwide to propel this field collectively to even greater heights.展开更多
基金supported by the Jiangsu Provincial Basic Research Program(Natural Science Foundation)Youth Fund(Grant No.BK20230885)the International Joint Laboratory of Sustainable Manufacturing,Ministry of Education and Fundamental Research Funds for Central Universities(Grant No.NG2024012)Major Project on Fundamental Research of Aero-Engines and Gas Turbines,Ministry of Industry and Information Technology Special Project on High-Quality Development(Grant No.J2022-Ⅶ-0006-0048)。
文摘Multi-material 3D sand printing has gained significant attention;however,research has mainly focused on materials and mechanisms,with limited exploration of optimizing the sand-laying process through numerical simulations.In this study,we investigated the dynamic behavior of sand particles during a vibratory sand-laying process for multi-material additive manufacturing using discrete element simulations.The objective is to enable precise control over the amount and distribution of sand for multi-material printing.In this study,we combined experiments and simulations to calibrate the contact parameters of different sands and establish a relationship between the curing agent content and surface energy of sand particles.A model for the vibratory fall of multimaterial sand was developed to study the motion characteristics of sand particles.This allows for macro-control over the sand spreading flow and high-quality multi-material sand laying.The results show that the flow rate of falling sand increases with decreasing surface energy of the particles,wider spreader openings,and higher vibration frequencies.For silica and chromite sands,when their surface energy ranged from 0.15 to 25 J·m^(2)and0.01-0.03 J·m^(2),respectively,and the sand spreader opening was 6 mm with a vibration frequency of 500 Hz,the sand flow rates of both materials became nearly identical.However,a higher sand paving speed and height increased the scattering of sand particles outside the target area,thereby decreasing the paving quality.The results accomplished in this study enable precise and uniform sand particle deposition and offers guidelines for optimizing sand speed and height,thus expanding the application of multi-material sand 3D printing in complex and high-performance manufacturing.
基金the support by National Key Research and Development Program of China(2018YFA0703000)National Natural Science Foundation of China(Grant No.52105310)+1 种基金Natural Science Foundation of Zhejiang Province(Grant No.LDQ23E050001)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(Grant No.SN-ZJU-SIAS-004)。
文摘In order to mimic the natural heterogeneity of native tissue and provide a better microenvironment for cell culturing,multi-material bioprinting has become a common solution to construct tissue models in vitro.With the embedded printing method,complex 3D structure can be printed using soft biomaterials with reasonable shape fidelity.However,the current sequential multi-material embedded printing method faces a major challenge,which is the inevitable trade-off between the printed structural integrity and printing precision.Here,we propose a simultaneous multi-material embedded printing method.With this method,we can easily print firmly attached and high-precision multilayer structures.With multiple individually controlled nozzles,different biomaterials can be precisely deposited into a single crevasse,minimizing uncontrolled squeezing and guarantees no contamination of embedding medium within the structure.We analyse the dynamics of the extruded bioink in the embedding medium both analytically and experimentally,and quantitatively evaluate the effects of printing parameters including printing speed and rheology of embedding medium,on the 3D morphology of the printed filament.We demonstrate the printing of double-layer thin-walled structures,each layer less than 200μm,as well as intestine and liver models with 5%gelatin methacryloyl that are crosslinked and extracted from the embedding medium without significant impairment or delamination.The peeling test further proves that the proposed method offers better structural integrity than conventional sequential printing methods.The proposed simultaneous multi-material embedded printing method can serve as a powerful tool to support the complex heterogeneous structure fabrication and open unique prospects for personalized medicine.
基金financial support from the China Scholarship Council(No.202108220036)Advanced Microscopy Laboratory in Trinity College Dublin。
文摘Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning of inorganic functional materials have been developed,they operate at small scale and require long processing times,restricting their effective translation from laboratory to market.Here we report a fast,liquid-free,cost-effective,and environmentally friendly aerosol-based printing method for fabricating linear or planar structures at microscale dimensions.In situ and on-demand generation of dry aerosol via pulsed laser ablation,coupled with real-time aerodynamical focusing using a co-flowing sheath gas,allows the deposition of a wide variety of materials on various substrates at room temperature and atmospheric pressure.Using silver as a test material,we systematically characterized the laser-generated aerosol deposits in terms of microstructural morphology,sintering activity,mass yield,density,and electrical performance,to show the relationship between process variability and underlying mechanisms.The capacity of high-throughput printing of silver deposits,with thickness up to 160μm,in a single pass was demonstrated.This rapid,efficient,and inkless printing process opens new and exciting opportunities for future applications that require easy-to-integrate components in printed electronic devices.
基金financially National Natural Science Foundation of China(Nos.52075209 and 51925503)Natural Science Foundation for Distinguished Young Scholars of Hubei province of China(No.2022CFA066)Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2021QNRC001)。
文摘Multi-material 3D fabrication at the nanoscale has been a long-sought goal in additive manufacturing,with great potential for the direct construction of functional micro/nanosystems rather than just arbitrary 3D structures.To achieve this goal,researchers have introduced several nanoscale 3D printing principles,explored various multi-material switching and combination strategies,and demonstrated their potential applications in 3D integrated circuits,optoelectronics,biological devices,micro/nanorobots,etc.Although some progress has been made,it is still at the primary stage,and a serious breakthrough is needed to directly construct functional micro/nano systems.In this perspective,the development,current status and prospects of multi-material 3D nanoprinting are presented.We envision that this 3D printing will unlock innovative solutions and make significant contributions to various technologies and industries in the near future.
文摘Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.
基金Project supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS-2025-02303676)。
文摘The stress minimization multi-material topology optimization(MMTO)approach has recently attracted significant attention because of its applications in aerospace and mechanical engineering.Nonetheless,the stress minimization MMTO approach may result in stress surpassing the material's tolerance limit,potentially culminating in failure.This research proposes a novel way for imposing stress constraints on each material to regulate their respective stress levels.The fundamental concept is that each material possesses its own interpolation function for the stress model.The maximum von Mises stress for each material can be established with the definition of an upper limit,ensuring that the materials will perform safely and effectively.This aids topological structures in resisting failure and augmenting strength.A multi-physics system including thermoelastic and self-weight loads is concurrently examined alongside stress limitations.The global stress constraint utilizes the p-norm function,and the adjoint method is used to derive sensitivity.This work employs a three-field strategy utilizing density filtering and Heaviside projection functions to mitigate the artificial stress in low density.The technique is assessed through two-dimensional(2D)and three-dimensional(3D)examples,illustrating the influence of stress limits on the compliance minimization under heat and self-weight loads.The optimized results indicate a substantial decrease in the stress levels accompanied by a minor gain in compliance,while maintaining the stress within the specified range for all materials.
基金supported by the National Natural Science Foundation of China(Nos.52575343 and 52175026)the Young Elite Scientists Sponsorship Program by CAST+2 种基金the Peiyang Startup FoundationFunding of Key Laboratory of Mechanism Theory and Equipment Design of the Ministry of EducationBasic Research Program of Coordinated Development of the Beijing Tianjin-Hebei Region(No.E2024202287)。
文摘Integrating inorganic fillers into polymer-based 3D printing filaments is an effective strategy for improving thermal conduction but often compromises mechanical properties.In this study,we introduced electrospun polymer nanofibers(NF)into thermoplastic polyurethane(TPU)filaments alongside a ceramic filler,boron nitride(BN).By combining these organic(NF)and inorganic(BN)fillers,we created a dual-filler filament(TPU/BN/NF)that exhibited enhanced thermal conduction pathways without sacrificing the mechanical strength and electrical insulation.Comprehensive characterization demonstrated that BN improved heat transport,while a small fraction of electrospun NF effectively modulated the tensile modulus and partially recovered the strength lost upon BN addition.Finite element simulations further elucidated the influence of the nanofiber content,orientation,and length-to-diameter ratio on the mechanical performance.Notably,the dual-filler filaments retained good printability in standard fused deposition modeling(FDM)systems at optimized temperatures(about 210??℃).These findings offer a scalable approach for engineer multifunctional 3D printing filaments for 3D-printed thermal management products that require both thermal conduction performance and high insulation.
文摘Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted drug delivery.For implants,mechanical properties are key performance characteristics,so understanding the deformation and failure mechanisms is essential for selecting the appropriate implant structure.The deformation and fracture processes in PLA samples with different interior architectures have been studied through computer simulation and experimental research.Two TPMS topologies,the Schwarz Diamond and Gyroid architectures,were used for the sample construction by 3D printing.ANSYS software was utilized to simulate compressive deformation.It was found that under the same load,the vonMises stresses in the Gyroid structure are higher than those in the Schwartz Diamond structure,which was associated with the different orientations of the cells in the studied structures in relation to the direction of the loading axis.The deformation process occurs in the local regions of the studied TPMS structures.Maximum von Mises stresses were observed in the vertical parts of the structures oriented along the load direction.It was found that,unlike the Gyroid,the Schwartz Diamond structure contains a frame that forms unique stiffening ribs,which ensures the redistribution of the load under the vertical loading direction.An analysis of the mechanical characteristics of PLA samples with the Schwartz Diamond and Gyroid structures produced by the Fused Deposition Modeling(FDM)method was correlated with computer simulation.The Schwarz Diamond-type structure was shown to have a higher absorption energy than the Gyroid one.A study of the fracture in PLA samples with various cell sizes revealed a particular feature related to the samples’periodic surface topology and the 3D printing process.Scanning electron microscopic(SEM)studies of the samples deformed by compression showed thatwith an increase in the density of the samples,the failure mechanism changes from ductile to quasi-brittle due to the complex participation of both cell deformation and fiber deformation.
文摘Most failures in component operation occur due to cyclic loads.Validation has been performed under quasistatic loads,but the fatigue life of components under dynamic loads should be predicted to prevent failures during component service life.Fatigue is a damage accumulation process where loads degrade the material,depending on the characteristics and number of repetitions of the load.Studies on themechanical fatigue of 3D-printedOnyx are limited.In this paper,the strength of 3D-printed Onyx components under dynamic conditions(repetitive loads)is estimated.Fatigue life prediction is influenced bymanufacturing processes,material properties,and applied loads,which can cause scatter in the results due to the interplay of these factors.By utilizing synthetic parameters derived from mechanical properties,the accuracy of fatigue life predictions has been improved significantly,from 23.13%to 98.33%.Additive manufacturing is flexible,but this flexibility generates scatter in the mechanical properties of produced components.This work also proposes the use of synthetic data with a neural network to improve the fatigue life prediction of printedOnyx subjected to tension–tension loads.Experimental uniaxial loads were used to characterize themechanical behaviorofprinted specimens.The experimental datawereused to evaluate thenumerical predictionsobtainedthrough finite element analysis using commercial software and an artificial neural network.The results showed that the use of synthetic data helped improve fatigue life prediction.
基金supported by the National Key R&D Program of China(No.2022YFE0208300)the National Natural Science Foundation of China(No.22278426)+2 种基金the China National Funds for Distinguished Young Scientists(No.22425808)the China Postdoctoral Science Foundation(No.2025M771155)the Science Foundation of China University of Petroleum,Beijing(Nos.2462024XKBH001,2462022YJRC003,2462022YJRC002,2462025BJRC002)。
文摘Electrochemical liquid lithium extraction technology has attracted much attention because of its high selectivity,good efficiency,and eco-friendliness.However,the low energy density per unit area and poor stability of traditional thin film electrodes(F-LMO),as well as manganese dissolution loss induced by the Jahn-Teller distortion of LiMn_(2)O_(4),hinder their industrial scalability.Herein,a durable and high-efficiency multistage porous LiMn_(2)O_(4) thick electrode was prepared sustainably by 3D printing technology(3DPLMO)for enhancing lithium recovery from salt lake brine.The multistage porous structure reduced the mass transfer resistance and shortened the ion diffusion path,which was conducive to accelerating the diffusion rate of Li+.Simultaneously,the three-dimensional conductive networks composed of reduced graphene oxide(r GO)and carbon nanotubes(CNT)synergized with the multistage pores effectively weakened the polarization phenomenon of the electrode and improved the stability of 3DP-LMO.The3DP-LMO exhibited a 5.5-fold higher extraction capacity per unit area and the Mn dissolution loss rate was only 1/15 compared with the F-LMO.Notably,the capacity retention rate of 3DP-LMO was 87.6%,significantly better than that of F-LMO(66.3%).Based on the quasi-in situ X-ray Diffraction results,the mechanism of lithium intercalation and deintercalation in 3DP-LMO was elucidated.Furthermore,lithium extraction parameters were optimized using response surface method-center composite design(RSM-CCD),resulting in an increase in lithium extraction capacity to 15.66 mg g^(-1)and a reduction in energy consumption to only 12.33 Wh mol^(-1).The results show that 3DP-LMO has significantly improved lithium extraction performance and stability,and has considerable prospects in practical application.
基金Deanship of Research and Graduate Studies at King Khalid University for funding this work through Large Research Project under grant number(R.G.P.2/472/46)Anhui Provoncial Natural Science Foundation(NO.2308085MF211).
文摘Demonstrating significant achievements in efficiency,perovskite solar cells(PSCs)have acquired unique positions in photovoltaics,offering alternatives to conventional commercial silicon solar cells.While there has been significant progress in enhancing photovoltaic performance,obvious stability problems remain a primary challenge that continues to hinder the commercial viability of PSCs.This present review first comprehensively discusses the main challenges to the commercialization of PSCs,including stability problems,ion migration,toxicity,and complexities in large-scale fabrication.It then effectively presents universal strategies to overcome the mentioned problems.Moreover,this review article examines various printing techniques that can be used to improve PSCs,emphasizing their benefits like low-cost components and procedures.Several printing processes are covered in the discussion,such as slot-die coating,spray coating,inkjet printing,doctor-blade coating,roll-to-roll printing,and screen printing.The potential uses of PSCs for the implementation of greenhouses,building-integrated photovoltaic systems,and indoor light energy harvesting.These uses highlight the adaptability of PSCs and demonstrate their ability to transform energy production technologies.Additionally,this review highlights the special qualities of perovskite materials that present chances to surpass silicon solar cells'efficiency restrictions and get close to the Shockley-Queisser limit.In conclusion,the current review provides a brief overview of recent developments,existing challenges,and opportunities of PSCs.It provides a thorough understanding of the merits of highly efficient PSCs fabricated by adopting printing methods to tackle stability problems along with facile fabrication of PSCs using simplified and cost-effective strategies.
基金financial support by the National Key Research and Development Program of China(No.2023YFB4605400)the National Natural Science Foundation of China(No.12472152)the Department of Science and Technology of Guangdong Province(No.2019QN01Z438)。
文摘Gradient refractive index(GRIN)metalenses are increasingly valued in high-frequency communication due to their exceptional radiation performance.Ceramics with high dielectric constants and low dielectric losses are ideal candidates for GRIN metalenses.Digital light processing(DLP)3D printing provides a feasible and efficient approach for manufacturing ceramic GRIN metalenses.However,the scattering of ultraviolet(UV)light by ceramic particles in the slurry reduces the printing accuracy of DLP technology,making it difficult to achieve the intricate structural features required for GRIN metalenses in high-frequency communication.In this work,we propose an approach to improve printing accuracy by optimizing the ceramic slurry composition and implementing a dimensional compensation design strategy.Utilizing geometric optics and the S-parameter inversion method,we design a GRIN metalens consisting of two distinct types of subwavelength unit cells(Y-shaped and circular hole geometries)with a minimum feature size of 160μm.Through a refined slurry formulation and precise design parameter compensation,high-fidelity ceramic GRIN metalenses are successfully fabricated.The fabricated metalens exhibits a maximum gain enhancement of 18.4 dBi and a deflection angle of±30°over a bandwidth of 37.84% in the W-band(75-110 GHz).The highly directional far-field beam radiation and efficient beam steering capabilities highlight the potential of ceramic GRIN metalenses for applications in satellite communications,radar systems,and other high-frequency technologies.
基金the support from the National Natural Science Foundation of China(Nos.22208376,UA22A20429)the Qingdao New Energy Shandong Laboratory Open Project(QNESL OP 202303)+3 种基金Shandong Provincial Natural Science Foundation(Nos.ZR2024QB175,ZR2023LFG005)Fundamental Research Funds for the Central Universities(No.25CX07002A)National Natural Science Foundation of China(Z202401390008)The Hunan Provincial Natural Science Foundation(2025JJ60301)。
文摘3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems.
基金National Key Research and Development Program Project of China(Grant No.2024YFC3506900)Tianjin Science and Technology Plan Project(Grant No.24JCYBJC00230)Party Building Innovation Research Project of Tianjin University of Traditional Chinese Medicine(Grant No.2024DJ03)。
文摘As bacterial infections have emerged as the second leading cause of death worldwide,the urgent demand for novel and effective antibacterial therapies continues to escalate.In this context,three-dimensional(3D)printing technology offers transformative potential for the design and fabrication of oral formulations,internal implants,and external dressings in the management of bacterial inflammation.Conventional oral antibacterial agents often suffer from limitations in drug release kinetics and gastrointestinal stability.Leveraging 3D printing enables precise control over drug release profiles,thereby enhancing both bioavailability and therapeutic efficacy.Moreover,the development of internal implants requires high levels of individual specificity and structural precision.Through patient-specific customization and the incorporation of appropriate antibacterial materials,3D printing allows the fabrication of implants tailored to individual clinical needs,ultimately increasing surgical success rates and minimizing postoperative infection risks.Additionally,3D-printed external dressings exhibit excellent antibacterial activity,accelerate wound healing,and facilitate patient recovery.This review summarizes the fabrication methods,key advantages,and therapeutic outcomes of 3D printing in oral delivery systems,implantable devices,and wound dressings.It further highlights recent advances and emerging trends,offering insights and strategic guidance for the rational design and application of antibacterial therapeutics.
基金supported by the National Natural Science Foundation of China(No.51905543)。
文摘This study aimed to systematically regulate the performance of 4D printing composites by investigating the synergistic effects of dicumyl peroxide(DCP)and maleic anhydride-grafted polyethylene(MAH-g-PE)on a poly(lactic acid)/thermoplastic polyurethane(PLA/TPU)matrix.Specifically,using a 70 wt%/30 wt%PLA/TPU matrix and an L_(9)(3^(2))orthogonal design,composites were evaluated via morphology,shape memory,mechanical tests,and multi-criteria analysis.Moderate DCP enhanced crosslinking,improving storage modulus and thermal stability,while excessive DCP caused brittleness.Furthermore,MAH-g-PE effectively improved interfacial compatibility,and its synergy with DCP was dosage-dependent.Consequently,Sample 5 achieved optimal performance,exhibiting uniform fracture morphology,a shape fixation rate of98.8%with the fastest recovery,and balanced strength-ductility.Multi-criteria analysis identified elongation at break and recovery time as the top contributing factors,with consistent rankings validated by Spearman analysis(ρ=0.833,p<0.01).In summary,adjusting DCP and MAH-g-PE contents effectively modulates the crosslinking structure and interfacial properties of PLA/TPU composites,providing a viable strategy for developing high-performance,tunable 4D printing materials.
基金supported by the National Natural Science Foundation of China(Nos.52473080,52403167 and 52173079)the Fundamental Research Funds for the Central Universities(Nos.xtr052023001 and xzy012023037)+1 种基金the Postdoctoral Research Project of Shaanxi Province(No.2024BSHSDZZ054)the Shaanxi Laboratory of Advanced Materials(No.2024ZY-JCYJ-04-12).
文摘Shape memory polymers used in 4D printing only had one permanent shape after molding,which limited their applications in requiring multiple reconstructions and multifunctional shapes.Furthermore,the inherent stability of the triazine ring structure within cyanate ester(CE)crosslinked networks after molding posed significant challenges for both recycling,repairing,and degradation of resin.To address these obstacles,dynamic thiocyanate ester(TCE)bonds and photocurable group were incorporated into CE,obtaining the recyclable and 3D printable CE covalent adaptable networks(CANs),denoted as PTCE1.5.This material exhibits a Young's modulus of 810 MPa and a tensile strength of 50.8 MPa.Notably,damaged printed PTCE1.5 objects can be readily repaired through reprinting and interface rejoining by thermal treatment.Leveraging the solid-state plasticity,PTCE1.5 also demonstrated attractive shape memory ability and permanent shape reconfigurability,enabling its reconfigurable 4D printing.The printed PTCE1.5 hinges and a main body were assembled into a deployable and retractable satellite model,validating its potential application as a controllable component in the aerospace field.Moreover,printed PTCE1.5 can be fully degraded into thiol-modified intermediate products.Overall,this material not only enriches the application range of CE resin,but also provides a reliable approach to addressing environmental issue.
基金the funding from the National Key Research and Development Program of China(No.2024YFB4607701)the Zhejiang Provincial Natural Science Foundation of China(No.LZ25E050001)+2 种基金the National Natural Science Foundation of China(No.52275294)State Key Laboratory of High-performance Precision Manufacturing(No.HPMKF202412)Zhejiang Province’s 2025‘Pioneer Leading Swan+X’Science and Technology Program(No.2025C02122).
文摘Cell engineering is transitioning from“making cells express products”to“directly manufacturing functional structures inside cells.”This perspective outlines two-photon polymerization(TPP)-based direct writing of polymerizable biocompatible materials to enable programmable micron-scale three-dimensional(3 D)functional architectures within living cells,thereby overcoming the limitations of simple endocytosis or phagocytosis.We highlight scalable workflows that couple bulk intracellular loading of biocompatible photoresists with automated TPP writing,and discuss how end ogenous proteins,biocompatible monomers,or biomate rials can be incorporated into these platforms as crosslinking elements to mitigate immune rejection and toxicity.This paradigm elevates the cell from a mere reaction vessel to an active factory,with direct implications for in vivo sensing,tracking,and precision drug delivery.However,key challenges remain,including establishing standardized material libraries,implementing autofocus and pose-adaptive control,and co-designing device architectures together with cellular functions.We anticipate that“intracellular 3 D printing”will provide a novel interface between synthetic biology and micro/nano-fabrication.
基金financially supported by the National Excellent Young Scientists Fund(NO.51525503)
文摘Sand mold 3 D printing technology is an advanced manufacturing technology which has great flexible manufacturing ability. A multi-material composite sand mold can control the temperature field of metallic parts during the pouring process, while the current sand mold 3 D printing technology can only fabricate a single material sand mold. The casting temperature field can not be adjusted by using single sand mold material with isotropous heat exchange ability during the pouring process. In this work, a kind of novel coating device was designed. Multi-material composite sand molds could be manufactured using the coating device according to the casting process demands of the final parts. The influences of curing agent content, coating velocity and scraper shape on compactness and surface roughness of the sand layer(silica sand and zircon sand) were studied. The shapes and sizes of transition intervals of two kinds of sand granules were also tested. The results show that, with the increase of the added volume of curing agent, the compactness of sand layer reduces and the surface roughness value rises. With the increase of the velocity of the coating device, the compactness of sand layer reduces and the surface roughness value rises similarly. In addition, the scraper with a dip angle of 72 degrees could increase the compactness value of the sand layer. The criteria of quality parmeters of the coating procedure are obtained. That is, the surface roughness(δ) of sand layer should be equal to or lesser than half of main size of the sand particles(Dm). The parameter H of the coating device which is the distance between the base of hopper and the surface of sand layer impacts the size of transition zone. The width of the transition zone is in direct proportion to the parameter H, qualitatively. Through the optimization of the coating device, high quality of multi-material sand layers can be obtained. This will provide a solution in manufacturing the multi-material composite sand mold.
基金The authors acknowledge the funding support from the National Natural Science Foundation of China(Nos.52175474 and 51775324)the China Scholarship Council(No.202006890054).
文摘Three-dimensional printing technologies exhibit tremendous potential in the advancing fields of tissue engineering and regenerative medicine due to the precise spatial control over depositing the biomaterial.Despite their widespread utilization and numerous advantages,the development of suitable novel biomaterials for extrusion-based 3D printing of scaffolds that support cell attachment,proliferation,and vascularization remains a challenge.Multi-material composite hydrogels present incredible potential in this field.Thus,in this work,a multi-material composite hydrogel with a promising formulation of chitosan/gelatin functionalized with egg white was developed,which provides good printability and shape fidelity.In addition,a series of comparative analyses of different crosslinking agents and processes based on tripolyphosphate(TPP),genipin(GP),and glutaraldehyde(GTA)were investigated and compared to select the ideal crosslinking strategy to enhance the physicochemical and biological properties of the fabricated scaffolds.All of the results indicate that the composite hydrogel and the resulting scaffolds utilizing TPP crosslinking have great potential in tissue engineering,especially for supporting neo-vessel growth into the scaffold and promoting angiogenesis within engineered tissues.
基金supported by the National Natural Science Foundation of China(Nos.52325504,52235007,and T2121004).
文摘As surgical procedures transition from conventional resection to advanced tissue-regeneration technologies,human disease therapy has witnessed a great leap forward.In particular,three-dimensional(3D)bioprinting stands as a landmark in this setting,by promising the precise integration of biomaterials,cells,and bioactive molecules,thus opening up a novel avenue for tissue/organ regeneration.Curated by the editorial board of Bio-Design and Manufacturing,this review brings together a cohort of leading young scientists in China to dissect the core functionalities and evolutionary trajectory of 3D bioprinting,by elucidating the intricate challenges encountered in the manufacturing of transplantable organs.We further delve into the translational pathway from scientific research to clinical application,emphasizing the imperativeness of establishing a regulatory framework and rigorously enforcing quality-control measures.Finally,this review outlines the strategic landscape and innovative achievements of China in this field and provides a comprehensive roadmap for researchers worldwide to propel this field collectively to even greater heights.
