Abnormal wound scarring often leads to functional impairments and cosmetic deformities,primarily driven by the prolonged activation of the TGF-β/Smad signaling pathway.Addressing this challenge,we developed a biomime...Abnormal wound scarring often leads to functional impairments and cosmetic deformities,primarily driven by the prolonged activation of the TGF-β/Smad signaling pathway.Addressing this challenge,we developed a biomimetic scaffold aimed at facilitating rapid and scarless wound healing.This highly in-tegrated 3D-printed dermal scaffold comprised modified recombinant human type III collagen(rhCOLIII-MA),gelatin methacrylate(GelMA),and liposomes encapsulating SB431542 to target TGF-β1(Lip@SB).The rhCOLIII-MA/GelMA(CG)scaffold retained inherent biomaterial characteristics,exhibited tailored physicochemical properties,and demonstrated favorable biocompatibility.Moreover,the Lip@SB-loaded CG scaffold(CGL)effectively promoted in vitro wound healing,while enabling controlled release of SB431542 to inhibit pathological collagen deposition.In a full-thickness skin defect rat model,the CGL dermal scaffold combined with split-thickness skin graft(STSG)minimized scar contraction,stimulated functional neovascularization,and enhanced graft aesthetics comparable to normal skin.Remarkably,the performance of the CGL scaffold surpassed that of commercially available anti-scarring alternatives.This innovative strategy presents a straightforward approach toward scarless skin regeneration and holds promise in alleviating the prolonged,painful postoperative rehabilitation.展开更多
The rapid advancement of three-dimensional printed concrete(3DPC)requires intelligent and interpretable frameworks to optimize mixture design for strength,printability,and sustainability.While machine learning(ML)mode...The rapid advancement of three-dimensional printed concrete(3DPC)requires intelligent and interpretable frameworks to optimize mixture design for strength,printability,and sustainability.While machine learning(ML)models have improved predictive accuracy,their limited transparency has hindered their widespread adoption in materials engineering.To overcome this barrier,this study introduces a Random Forests ensemble learning model integrated with SHapley Additive exPlanations(SHAP)and Partial Dependence Plots(PDPs)to model and explain the compressive strength behavior of 3DPC mixtures.Unlike conventional“black-box”models,SHAP quantifies each variable’s contribution to predictions based on cooperative game theory,which enables causal interpretability,whereas PDP visualizes nonlinear and interactive effects between features that offer practical mix design insights.A systematically optimized random forest model achieved strong generalization(R2=0.978 for training,0.834 for validation,and 0.868 for testing).The analysis identified curing age,Portland cement,silica fume,and the water-tobinder ratio as dominant predictors,with curing age exerting the highest positive influence on strength development.The integrated SHAP-PDP framework revealed synergistic interactions among binder constituents and curing parameters,which established transparent,data-driven guidelines for performance optimization.Theoretically,the study advances explainable artificial intelligence in cementitious material science by linking microstructural mechanisms to model-based reasoning,thereby enhancing both the interpretability and applicability of ML-driven mix design for next-generation 3DPC systems.展开更多
3D-printed Ti_(3)C_(2)T_(x) MXene-based interdigital micro-supercapacitors(MSCs)have great potential as energy supply devices in the field of microelectronics due to their short ion diffusion path,high conductivity,ex...3D-printed Ti_(3)C_(2)T_(x) MXene-based interdigital micro-supercapacitors(MSCs)have great potential as energy supply devices in the field of microelectronics due to their short ion diffusion path,high conductivity,excellent pseudocapacitance,and fast charging capabilities.However,searching for eco-friendly aqueous Ti_(3)C_(2)T_(x) MXene-based inks without additives and preventing severe restack of MXene nanosheets in high-concentration inks are significantly challenging.This study develops an additive-free,highly printable,viscosity adjustable,and environmentally friendly MXene/carbon nanotube(CNT)hybrid aqueous inks,in which the CNT can not only adjust the viscosity of Ti_(3)C_(2)T_(x) MXene inks but also widen the interlayer spacing of adjacent Ti_(3)C_(2)T_(x) MXene nanosheets effectively.The optimized MXene/CNT composite inks are successfully adopted to construct various configurations of MSCs with remarkable shape fidelity and geometric accuracy,together with enhanced surface area accessibility for electrons and ions diffusion.As a result,the constructed interdigital symmetrical MSCs demonstrate outstanding areal capacitance(1249.3 mF cm^(-2)),superior energy density(111μWh cm^(-2) at 0.4mWcm^(-2)),and high power density(8mWcm^(-2) at 47.1μWh cm^(-2)).Furthermore,a self-powered modular system of solar cells integrated with MXene/CNT-MSCs and pressure sensors is successfully tailored,simultaneously achieving efficient solar energy collection and real-time human activities monitoring.This work offers insight into the understanding of the role of CNTs in MXene/CNT ink.Moreover,it provides a new approach for preparing environmentally friendly MXene-based inks for the 3D printing of high-performance MSCs,contributing to the development of miniaturized,flexible,and self-powered printable electronic microsystems.展开更多
Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailora...Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailorable structures and compositions,diverse functionalities,and well-controlled pore/size distribution.However,most developed MOFs are in powder forms,which still have some technical challenges,including abrasion,dustiness,low packing densities,clogging,mass/heat transfer limitation,environmental pollution,and mechanical instability during the packing process,that restrict their applicability in industrial applications.Therefore,in recent years,attention has focused on techniques to convert MOF powders into macroscopic materials like beads,membranes,monoliths,gel/sponges,and nanofibers to overcome these challenges.Three-dimensional(3D)printing technology has achieved much interest because it can produce many high-resolution macroscopic frameworks with complex shapes and geometries from digital models.Therefore,this review summarizes the combination of different 3D printing strategies with MOFs and MOF-based materials for fabricating 3D-printed MOF monoliths and their environmental applications,emphasizing water treatment and gas adsorption/separation applications.Herein,the various strategies for the fabrication of 3D-printed MOF monoliths,such as direct ink writing,seed-assisted in-situ growth,coordination replication from solid precursors,matrix incorporation,selective laser sintering,and digital light processing,are described with the relevant examples.Finally,future directions and challenges of 3D-printed MOF monoliths are also presented to better plan future trajectories in the shaping of MOF materials with improved control over the structure,composition,and textural properties of 3D-printed MOF monoliths.展开更多
Here,we report the production of 3D-printed MoS_(2)/Ni electrodes(3D-MoS_(2)/Ni)with longterm stability and excellent performance by the selective laser melting(SLM)technique.As a cathode,the obtained 3D-MoS_(2)/Ni co...Here,we report the production of 3D-printed MoS_(2)/Ni electrodes(3D-MoS_(2)/Ni)with longterm stability and excellent performance by the selective laser melting(SLM)technique.As a cathode,the obtained 3D-MoS_(2)/Ni could maintain a degradation rate above 94.0%for forfenicol(FLO)when repeatedly used 50 times in water.We also found that the removal rate of FLO by 3D-MoS_(2)/Ni was about 12 times higher than that of 3D-printed pure Ni(3D-Ni),attributed to the improved accessibility of H^(*).In addition,the electrochemical characterization results showed that the electrochemically active surface area of the 3D-MoS_(2)/Ni electrode is about 3-fold higher than that of the 3D-Ni electrode while the electrical resistance is 4 times lower.Based on tert-butanol suppression,electron paramagnetic resonance and triple quadrupole mass spectrometer experiments,a“dual path”mechanism and possible degradation pathway for the dechlorination of FLO by 3D-MoS_(2)/Ni were proposed.Furthermore,we also investigated the impacts of the cathode potential and the initial pH of the solution on the degradation of FLO.Overall,this study reveals that the SLM 3D printing technique is a promising approach for the rapid fabrication of high-stability metal electrodes,which could have broad application in the control of water contaminants in the environmental field.展开更多
In the current study poly(lactic acid)PLA composites with a 3 wt%and 5 wt%of nanofibrillated cellulose(NFC)were produced by 3D-printing method.An enzymatic pretreatment coupled with mechanical fibrillation in a twin s...In the current study poly(lactic acid)PLA composites with a 3 wt%and 5 wt%of nanofibrillated cellulose(NFC)were produced by 3D-printing method.An enzymatic pretreatment coupled with mechanical fibrillation in a twin screw extruder was used to produce high consistency NFC.Scanning electron microscopy(SEM)equipped with Fibermetric software,FASEP fiber length distribution analysis,Furrier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),tensile tests,impact tests and differential scanning calorimetry were used to characterize NFC and PLA/NFC composites.The results of the fiber length and width measurements together with the results of the SEM analysis showed that enzymatic hydrolysis coupled with a twin screw extrusion could effectively reduce the diameter and length of cellulose fibers.The produced NFC consisted of microand nanosized fibers entangled in a characteristic 3D-network.Based on the FT-IR analysis,no new bonds were formed during the enzymatic hydrolysis or fibrillation process.The TGA analysis confirmed that produced NFC can be used in hightemperature extrusion processing without NFC degradation.During the PLA/NFC composites preparation the NFC agglomerates were formed,which negatively influenced PLA/NFC composites impact properties.The slightly improved tensile strength and elastic modulus were reported for all composites when compared to the neat PLA.The elongation at break was not affected by the NFC addition.No significant differences in thermal stability were detectable among composites nor in comparation with the neat PLA.However,the crystallinity degree of the composite containing 5 wt%NFC was increased in respect to the neat PLA.展开更多
The architecture and surface modifications have been regarded as effective methods to enhance the bi-ological response of biomaterials in bone tissue engineering.The porous architecture of the implanta-tion was essent...The architecture and surface modifications have been regarded as effective methods to enhance the bi-ological response of biomaterials in bone tissue engineering.The porous architecture of the implanta-tion was essential conditions for bone regeneration.Meanwhile,the design of biomimetic hydroxyap-atite(HAp)coating on porous scaffolds was demonstrated to strengthen the bioactivity and stimulate osteogenesis.However,bioactive bio-ceramics such asβ-tricalcium phosphate(β-TCP)and calcium sili-cate(CS)with superior apatite-forming ability were reported to present better osteogenic activity than that of HAp.Hence in this study,3D-printed interconnected porous bioactive ceramicsβ-TCP/CS scaf-fold was fabricated and the biomimetic HAp apatite coating were constructed in situ via hydrothermal reaction,and the effects of HAp apatite layer on the fate of mouse bone mesenchymal stem cells(mBM-SCs)and the potential mechanisms were explored.The results indicated that HAp apatite coating en-hanced cell proliferation,alkaline phosphatase(ALP)activity,and osteogenic gene expression.Further-more,PI3K/AKT/mTOR signaling pathway is proved to have an important impact on cellular functions.The present results demonstrated that the key molecules of phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT)and mammalian target of rapamycin(mTOR)were activated after the biomimetic hydrox-yapatite coating were constructed on the 3D-printed ceramic scaffolds.Besides,the activated influence on the protein expression of Runx2 and BMP2 could be suppressed after the treatment of inhibitor HY-10358.In vivo studies showed that the constructed HAp coating promoted bone formation and strengthen the bone quality.These results suggest that biomimetic HAp coating constructed on the 3D-printed bioac-tive composite scaffolds could strengthen the bioactivity and the obtained biomimetic multi-structured scaffolds might be a potential alternative bone graft for bone regeneration.展开更多
The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidenc...The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidence angles up to 60°.The CFSR consists of four functional layers separated by three dielectric slabs,which includes lossless metasurface-Ⅰ(MS-Ⅰ),loss metasurface-Ⅱ(MS-Ⅱ),loss metasurface-Ⅲ(MS-Ⅲ),and a three-dimensional metastructure(3D-MS).MS-Ⅰfunctions as a reflector for two absorption bands with a minimal insertion loss transmission window.MS-Ⅱis designed for high-frequency absorption.MS-Ⅲserves as a low-frequency absorption layer for CFSR and an impedance matching layer for MS-Ⅱ.The design methodologies for the transmission window in MS-III and the introduction of 3D-MS are key to achieving high-performance CFSR.The physical mechanisms of CFSR are explained through equivalent circuit model(ECM)analysis and impedance characterization.Finally,measurement results confirm that the proposed CFSR exhibits a−1 dB transmission band ranging from 8.79 to 10.41 GHz with a minimum insertion loss of 0.44 dB at 9.59 GHz;furthermore,the frequency range where reflection coefficient remains below−10 dB is measured to be between 3.33 and 18.00 GHz,aligning well with simulation outcomes.展开更多
A liquid Li divertor is a promising alternative for future fusion devices.In this work a new divertor model is proposed,which is processed by 3D-printing technology to accurately control the size of the internal capil...A liquid Li divertor is a promising alternative for future fusion devices.In this work a new divertor model is proposed,which is processed by 3D-printing technology to accurately control the size of the internal capillary structure.At a steady-state heat load of 10 MW m^(-2),the thermal stress of the tungsten target is within the bearing range of tungsten by finite-element simulation.In order to evaluate the wicking ability of the capillary structure,the wicking process at 600℃ was simulated by FLUENT.The result was identical to that of the corresponding experiments.Within 1 s,liquid lithium was wicked to the target surface by the capillary structure of the target and quickly spread on the target surface.During the wicking process,the average wicking mass rate of lithium should reach 0.062 g s^(-1),which could even supplement the evaporation requirement of liquid lithium under an environment>950℃.Irradiation experiments under different plasma discharge currents were carried out in a linear plasma device(SCU-PSI),and the evolution of the vapor cloud during plasma irradiation was analyzed.It was found that the target temperature tends to plateau despite the gradually increased input current,indicating that the vapor shielding effect is gradually enhanced.The irradiation experiment also confirmed that the 3D-printed tungsten structure has better heat consumption performance than a tungsten mesh structure or multichannel structure.These results reveal the application potential and feasibility of a 3D-printed porous capillary structure in plasma-facing components and provide a reference for further liquid-solid combined target designs.展开更多
Sodium(Na)metal batteries have gained increasing attention more recently,owing to their high energy densities and cost efficiencies,but are severely handicapped by the unsatisfactory Coulombic efficiency(CE)and cyclin...Sodium(Na)metal batteries have gained increasing attention more recently,owing to their high energy densities and cost efficiencies,but are severely handicapped by the unsatisfactory Coulombic efficiency(CE)and cycling stability stemming from dendrite growth on Na anodes.In this study,we developed a strategy of direct ink writing(DIW)3D printing combined with electroless deposition to construct a hierarchical Cu grid coated with a dense nanoscale Ag interfacial layer as the host material for Na plating.The sodiophilic Ag interface contributes to a fall in the Na nucleation energy,hence enabling uniform Na deposition on each 3D-printed filament.The constructed 3D-printed structure can effectively moderate the electric-field distribution and lower the local current density for relieving Na inhomogeneous growth,as confirmed by finite element simulation and Na plating/stripping morphology evolution results.In particular,the unique 3D structure also promotes the lateral growth of Na,thus the volume change of Na metal was accommodated to stabilize the solid electrolyte interphase(SEI).As a result,the CE of the half-cell can reach 99.9%at the current density of 1 m A/cm^(2)after 300 cycles and the full-cell exhibits outstanding electrochemical performance(capacity retention of 91.0%after 500 cycles at 2 C).展开更多
In this work,we reported a series of monolithic 3D-printed Ni-Mo alloy electrodes for highly efficient water splitting at high current density(1500 mA cm^(-2))with excellent stability,which provides a solution to scal...In this work,we reported a series of monolithic 3D-printed Ni-Mo alloy electrodes for highly efficient water splitting at high current density(1500 mA cm^(-2))with excellent stability,which provides a solution to scale up Ni-Mo catalysts for HER to industry use.All possible Ni-Mo metal/alloy phases were achieved by tuning the atomic composition and heat treatment procedure,and they were investigated through both experiment and simulation,and the optimal NiMo phase shows the best performance.Density functional theory(DFT)calculations elucidate that the NiMo phase has the lowest H2O dissociation energy,which further explains the exceptional performance of NiMo.In addition,the microporosity was modulated via controlled thermal treatment,indicating that the 1100℃sintered sample has the best catalytic performance,which is attributed to the high electrochemically active surface area(ECSA).Finally,the four different macrostructures were achieved by 3D printing,and they further improved the catalytic performance.The gyroid structure exhibits the best catalytic performance of driving 500 mA cm^(-2)at a low overpotential of 228 mV and 1500 mA cm^(-2)at 325 mV,as it maximizes the efficient bubble removal from the electrode surface,which offers the great potential for high current density water splitting.展开更多
Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasit...Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasitism defense behavior,and their taxidermy specimens have been widely used as a set of standard methods for the study of avian brood parasitism.In recent years,with the rapid development of 3D-printing technology,3D-printed bird models are expected to be applied as a standard method in the study of avian brood parasitism.To evaluate the use of 3D-printed models,this study tests the reaction of Oriental Reed Warbler(Acrocephalus orientalis)towards predators,parasites,or controls,and compares the reaction among different nest intruders and between taxidermy specimens and 3D-printed animal models.It was found that the Oriental Reed Warbler responded most aggressively to the parasite,followed by predator,and finally the control;the results were consistent between the reaction to taxidermy specimens and 3D-printed animal models,indicating that 3D-printed models could serve as a substitute for taxidermy specimens.We propose a series of advantages of using 3D-printed models and suggest them to be a standard method for widespread use in future studies of avian brood parasitism.展开更多
To improve the strength of carbon fiber(CF) reinforced Polycaprolactam(PA6) composites, controlled amounts of carbon nanotubes(CNTs) were grafted onto the surface of CF to prepare the hybrid reinforcement(HR). We used...To improve the strength of carbon fiber(CF) reinforced Polycaprolactam(PA6) composites, controlled amounts of carbon nanotubes(CNTs) were grafted onto the surface of CF to prepare the hybrid reinforcement(HR). We used HR to fabricate laminate and H-sample to test the interfacial bonding strength(IBS) of the composites by means of a novel process called three-dimensional printed molding(3 D-PM). By using the melt drop printing method, we measured the contact angles between PA6 and CF(without sizing) and between PA6 and HR. The IBS and the mechanical properties of the composites were obtained by the tensile test. The experimental result indicated that CF grafted by 0.25% weight fraction of CNT or more could develop a special microstructure similar to the micro-pits on the surface of CF, which improved the wettability of CF and PA6 due to the increased surface area and the roughness of CF. When the weight fraction of CNT reached 0.25%, the IBS increased by 41.8%, the tensile strength by 130%, and the interfacial shear strength(IFSS) by 238%. The interfacial dimple fracture was observed by Scanning Electron Microscope(SEM), which revealed that the composites were able to absorb more deforming energy before fracture. The modified surface microstructure of CF would prevent crack propagation at the interface and increase the mechanical properties of thermoplastic composites(TPCs).展开更多
The study aimed to explore the feasibility of an image registration technique for assessing the accuracy of intraoperative osteotomy of pelvic tumors by 3-dimensional(3D)-printed patient-specific templates.Patients wi...The study aimed to explore the feasibility of an image registration technique for assessing the accuracy of intraoperative osteotomy of pelvic tumors by 3-dimensional(3D)-printed patient-specific templates.Patients with malignant pelvic tumors who were admitted to our hospital between March 2014 and December 2020 were retrospectively enrolled.Patients underwent hemi-pelvic resection and reconstruction by 3D-printed individualized prostheses.The registration between the designed model and the postoperative segmented model of the prosthesis was used to obtain the intraoperative osteotomy plane and reduce metal artifacts in postoperative computed tomography(CT)images.The distance and angle between the planned and actual osteotomy planes were then used to assess the accuracy of the intraoperative osteotomy.Eight patients with 13 osteotomy planes were enrolled,including four males and four females.The median age at the time of imaging examination was 44 years(range,33–54 years).All intraoperative osteotomy planes were assessed successfully.The mean distance between the planned and true intraoperative osteotomy planes was−0.69 cm(−7.5–7.35 cm),and the mean angle was 6.57°±3.36°(1.05°–11.88°).This new assessment method of registering the designed model and the postoperative CT segmented model of the prosthesis may be used to assess the accuracy of intraoperative osteotomy for pelvic tumors,using 3D printed patient-specific templates.展开更多
Osteochondral lesion of the talus(OLT)is a common cause of ankle pain that often occurs in the talar dome and leads to talar cartilage and subchondral bone damage.Osteochondral autograft transplantation is a logical t...Osteochondral lesion of the talus(OLT)is a common cause of ankle pain that often occurs in the talar dome and leads to talar cartilage and subchondral bone damage.Osteochondral autograft transplantation is a logical treatment option.It is known that if the cartilage does not heal properly after injury,it degenerates,and osteoarthritis worsens.A three dimensional(3D)-printed guide plate can be used to find the curved articular surface from the donor site which optimally fits the defect in the talus.Herein,we present the case of a 28-year-old man who had an open injury from the crash of a tricycle in the right ankle at the age of 5.Radiographs revealed a large defect in the medial talar dome that affected nearly half of the talar dome.We performed the debridement of the ankle lesion.An osteochondral autograft was harvested from the medial femoral condyle(MFC)with the help of a personalised 3D-printed guide plate.This 3D-printed guide plate simulated the contour of a specific area in the talar dome,which involved the site of the defect.The autograft was then transplanted into the talus defect.The efficacy of this technique was evaluated at 2,4,and 7 months after surgery and proven to be reliable.展开更多
Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically investig...Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically investigated.Three physical models of DFNs were 3D-printed and then computed tomography(CT)-scanned to obtain the specific geometry of fractures.The validity of numerically simulating the fluid flow through DFNs was verified via comparison with flow tests on the 3D-printed models.A parametric study was then implemented to establish quantitative relations between the coefficients/parameters in Forchheimer’s law and geometrical parameters.The results showed that the 3D-printing technique can well reproduce the geometry of single fractures with less precision when preparing complex fracture networks,numerical modeling precision of which can be improved via CT-scanning as evidenced by the well fitted results between fluid flow tests and numerical simulations using CT-scanned digital models.Streamlines in DFNs become increasingly tortuous as the fracture number and roughness increase,resulting in stronger inertial effects and greater curvatures of hydraulic pressure-low rate relations,which can be well characterized by the Forchheimer’s law.The critical hydraulic gradient for the onset of nonlinear flow decreases with the increasing aperture,fracture number and roughness,following a power function.The increases in fracture aperture and number provide more paths for fluid flow,increasing both the viscous and inertial permeabilities.The value of the inertial permeability is approximately four orders of magnitude greater than the viscous permeability,following a power function with an exponent a of 3,and a proportional coefficient b mathematically correlated with the geometrical parameters.展开更多
Titanium(Ti)and its alloys have been extensively explored for treating load-bearing bone defects.How-ever,high-stress shielding,weak osteogenic activity,and insufficient vascularization remain key chal-lenges for the ...Titanium(Ti)and its alloys have been extensively explored for treating load-bearing bone defects.How-ever,high-stress shielding,weak osteogenic activity,and insufficient vascularization remain key chal-lenges for the long-term clinical outcomes of Ti-based implants.Herein,inspired by structural and func-tional cues of bone regeneration,a silicon-doped nano-hydroxyapatite(nSiHA)/titanium dioxide(TiO_(2))composite coating with a hierarchical micro/nano-network structure is constructed on the surface of a 3D-printed porous Ti scaffold via a combined strategy of acid-alkali(AA)treatment and electrochemi-cal deposition technique,which not only endows the scaffold with excellent osteoinduction ability but can also effectively immobilize and release vascular endothelial growth factor(VEGF).The results of the in vitro cell experiments show that the functionalized Ti scaffold significantly promotes osteogenesis in bone marrow mesenchymal stem cells(BMSCs)and angiogenesis in human umbilical vein endothelial cells(HUVECs)by activating the extracellular signal-regulated protein kinase(ERK)and HIF-1αsignaling pathways.After being implanted into a rat femoral condyle defect model,the functionalized Ti scaffold can induce in situ vascularized bone regeneration by orchestrating the two coupled processes of angio-genesis and osteogenesis.These findings indicate that the functionalized Ti scaffold has great potential in bone tissue regeneration and is a promising candidate for load-bearing bone defect repair.展开更多
Superconducting YBa_(2)Cu_(3)O_(7−x)(YBCO)bulks have promising applications in quasi-permanent magnets,levitation,etc.Recently,a new way of fabricating porous YBCO bulks,named direct-ink-writing(DIW)3D-printing method...Superconducting YBa_(2)Cu_(3)O_(7−x)(YBCO)bulks have promising applications in quasi-permanent magnets,levitation,etc.Recently,a new way of fabricating porous YBCO bulks,named direct-ink-writing(DIW)3D-printing method,has been reported.In this method,the customized precursor paste and programmable shape are two main advantages.Here,we have put forward a new way to customize the YBCO 3D-printing precursor paste which is doped with Al_(2)O_(3)nanoparticles to obtain YBCO with higher thermal conductivity.The great rheological properties of precursor paste after being doped with Al_(2)O_(3)nanoparticles can help the macroscopic YBCO samples with high thermal conductivity fabricated stably with high crystalline and lightweight properties.Test results show that the peak thermal conductivity of Al_(2)O_(3)-doped YBCO can reach twice as much as pure YBCO,which makes a great effort to reduce the quench propagation speed.Based on the microstructure analysis,one can find that the thermal conductivity of Al_(2)O_(3)-doped YBCO has been determined by its components and microstructures.In addition,a macroscopic theoretical model has been proposed to assess the thermal conductivity of different microstructures,whose calculated results take good agreement with the experimental results.Meanwhile,a microstructure with high thermal conductivity has been found.Finally,a macroscopic YBCO bulk with the presented high thermal conductivity microstructure has been fabricated by the Al_(2)O_(3)-doped method.Compared with YBCO fabricated by the traditional 3D-printed,the Al_(2)O_(3)-doped structural YBCO bulks present excellent heat transfer performances.Our customized design of 3D-printing precursor pastes and novel concept of structural design for enhancing the thermal conductivity of YBCO superconducting material can be widely used in other DIW 3D-printing materials.展开更多
This study represents an important step forward in the domain of additive manufacturing of energetic materials.It presents the successful formulation and fabrication by 3D printing of gun propellants using Fused Depos...This study represents an important step forward in the domain of additive manufacturing of energetic materials.It presents the successful formulation and fabrication by 3D printing of gun propellants using Fused Deposition Modeling(FDM)technology,highlighting the immense potential of this innovative approach.The use of FDM additive manufacturing technology to print gun propellants is a significant advancement due to its novel application in this field,which has not been previously reported.Through this study,the potential of FDM 3D-printing in the production of high-performance energetic composites is demonstrated,and also a new standard for manufacturability in this field can be established.The thermoplastic composites developed in this study are characterized by a notably high energetic solids content,comprising 70%hexogen(RDX)and 10%nitrocellulose(NC),which surpasses the conventional limit of 60%energetic solids typically achieved in stereolithography and light-curing 3D printing methods.The primary objective of the study was to optimize the formulation,enhance performance,and establish an equilibrium between printability and propellant efficacy.Among the three energetic for-mulations developed for 3D printing feedstock,only two were suitable for printing via the FDM tech-nique.Notably,the formulation consisting of 70%RDX,10%NC,and 20%polycaprolactone(PCL)emerged as the most advantageous option for gun propellants,owing to its exceptional processability,ease of printability,and high energetic performance.展开更多
The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the act...The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the actual porosity and pore size of the prepared P model for each pore size are greater than the designed values.The addition of Ca changes the second phase of the alloy from Mg_(2)Sn to CaMgSn and refines its microstructure.The compressive yield strength and compressive modulus of the Mg−1Zn−1Sn−0.2Ca alloy scaffold reach 32.61 MPa and 0.23 GPa,respectively.The corrosion current density is measured at 14.64μA/cm^(2),with an instantaneous corrosion rate of 0.335 mm/a.Both scaffolds exhibit excellent biocompatibility and no cytotoxicity.Additionally,the antibacterial effects of both alloys on E.coli are greater than 97.81%.These results indicate that Mg alloy scaffolds have great potential for clinical applications.展开更多
基金supported by the National Natural Science Foundation of China(No.82272297).
文摘Abnormal wound scarring often leads to functional impairments and cosmetic deformities,primarily driven by the prolonged activation of the TGF-β/Smad signaling pathway.Addressing this challenge,we developed a biomimetic scaffold aimed at facilitating rapid and scarless wound healing.This highly in-tegrated 3D-printed dermal scaffold comprised modified recombinant human type III collagen(rhCOLIII-MA),gelatin methacrylate(GelMA),and liposomes encapsulating SB431542 to target TGF-β1(Lip@SB).The rhCOLIII-MA/GelMA(CG)scaffold retained inherent biomaterial characteristics,exhibited tailored physicochemical properties,and demonstrated favorable biocompatibility.Moreover,the Lip@SB-loaded CG scaffold(CGL)effectively promoted in vitro wound healing,while enabling controlled release of SB431542 to inhibit pathological collagen deposition.In a full-thickness skin defect rat model,the CGL dermal scaffold combined with split-thickness skin graft(STSG)minimized scar contraction,stimulated functional neovascularization,and enhanced graft aesthetics comparable to normal skin.Remarkably,the performance of the CGL scaffold surpassed that of commercially available anti-scarring alternatives.This innovative strategy presents a straightforward approach toward scarless skin regeneration and holds promise in alleviating the prolonged,painful postoperative rehabilitation.
基金supported by the Ongoing Research Funding Program(Grant No.ORFFT-2025-025-4)at King Saud University,Riyadh,Saudi Arabia.The grant was awarded to Yassir M.Abbas。
文摘The rapid advancement of three-dimensional printed concrete(3DPC)requires intelligent and interpretable frameworks to optimize mixture design for strength,printability,and sustainability.While machine learning(ML)models have improved predictive accuracy,their limited transparency has hindered their widespread adoption in materials engineering.To overcome this barrier,this study introduces a Random Forests ensemble learning model integrated with SHapley Additive exPlanations(SHAP)and Partial Dependence Plots(PDPs)to model and explain the compressive strength behavior of 3DPC mixtures.Unlike conventional“black-box”models,SHAP quantifies each variable’s contribution to predictions based on cooperative game theory,which enables causal interpretability,whereas PDP visualizes nonlinear and interactive effects between features that offer practical mix design insights.A systematically optimized random forest model achieved strong generalization(R2=0.978 for training,0.834 for validation,and 0.868 for testing).The analysis identified curing age,Portland cement,silica fume,and the water-tobinder ratio as dominant predictors,with curing age exerting the highest positive influence on strength development.The integrated SHAP-PDP framework revealed synergistic interactions among binder constituents and curing parameters,which established transparent,data-driven guidelines for performance optimization.Theoretically,the study advances explainable artificial intelligence in cementitious material science by linking microstructural mechanisms to model-based reasoning,thereby enhancing both the interpretability and applicability of ML-driven mix design for next-generation 3DPC systems.
基金supported by the National Natural Science Foundation of China(52174247,52477213,52401244 and 22302066)Science and Technology Innovation Program of Hunan Province(No.2022RC1088)+2 种基金Natural Science Foundation of Hunan Province(2023JJ40255)Zhejiang Provincial Natural Science Foundation of China(No.LQ24B020005)Scientific Research Foundation of Hunan Provincial Education Department(22B0599 and 23A0442).
文摘3D-printed Ti_(3)C_(2)T_(x) MXene-based interdigital micro-supercapacitors(MSCs)have great potential as energy supply devices in the field of microelectronics due to their short ion diffusion path,high conductivity,excellent pseudocapacitance,and fast charging capabilities.However,searching for eco-friendly aqueous Ti_(3)C_(2)T_(x) MXene-based inks without additives and preventing severe restack of MXene nanosheets in high-concentration inks are significantly challenging.This study develops an additive-free,highly printable,viscosity adjustable,and environmentally friendly MXene/carbon nanotube(CNT)hybrid aqueous inks,in which the CNT can not only adjust the viscosity of Ti_(3)C_(2)T_(x) MXene inks but also widen the interlayer spacing of adjacent Ti_(3)C_(2)T_(x) MXene nanosheets effectively.The optimized MXene/CNT composite inks are successfully adopted to construct various configurations of MSCs with remarkable shape fidelity and geometric accuracy,together with enhanced surface area accessibility for electrons and ions diffusion.As a result,the constructed interdigital symmetrical MSCs demonstrate outstanding areal capacitance(1249.3 mF cm^(-2)),superior energy density(111μWh cm^(-2) at 0.4mWcm^(-2)),and high power density(8mWcm^(-2) at 47.1μWh cm^(-2)).Furthermore,a self-powered modular system of solar cells integrated with MXene/CNT-MSCs and pressure sensors is successfully tailored,simultaneously achieving efficient solar energy collection and real-time human activities monitoring.This work offers insight into the understanding of the role of CNTs in MXene/CNT ink.Moreover,it provides a new approach for preparing environmentally friendly MXene-based inks for the 3D printing of high-performance MSCs,contributing to the development of miniaturized,flexible,and self-powered printable electronic microsystems.
文摘Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailorable structures and compositions,diverse functionalities,and well-controlled pore/size distribution.However,most developed MOFs are in powder forms,which still have some technical challenges,including abrasion,dustiness,low packing densities,clogging,mass/heat transfer limitation,environmental pollution,and mechanical instability during the packing process,that restrict their applicability in industrial applications.Therefore,in recent years,attention has focused on techniques to convert MOF powders into macroscopic materials like beads,membranes,monoliths,gel/sponges,and nanofibers to overcome these challenges.Three-dimensional(3D)printing technology has achieved much interest because it can produce many high-resolution macroscopic frameworks with complex shapes and geometries from digital models.Therefore,this review summarizes the combination of different 3D printing strategies with MOFs and MOF-based materials for fabricating 3D-printed MOF monoliths and their environmental applications,emphasizing water treatment and gas adsorption/separation applications.Herein,the various strategies for the fabrication of 3D-printed MOF monoliths,such as direct ink writing,seed-assisted in-situ growth,coordination replication from solid precursors,matrix incorporation,selective laser sintering,and digital light processing,are described with the relevant examples.Finally,future directions and challenges of 3D-printed MOF monoliths are also presented to better plan future trajectories in the shaping of MOF materials with improved control over the structure,composition,and textural properties of 3D-printed MOF monoliths.
基金supported by the Guangdong Province Youth Innovative Talents Project in Higher Education (No.2018KQNCX257)the Guangdong Province Enterprise Science and Technology Commissioner Project (No.GDKTP2021048000)+4 种基金the Key-Area Research and Development Program of Guangdong Province (No.2020B090923002)the Guangdong-Dongguan Joint Fund (No.2019B151530005)the Guangdong Basic and Applied Basic Research Foundation (No.2019A1515110497)the National Natural Science Foundation of China (No.41907292)the National Natural Science Foundation of China (No.21876130)。
文摘Here,we report the production of 3D-printed MoS_(2)/Ni electrodes(3D-MoS_(2)/Ni)with longterm stability and excellent performance by the selective laser melting(SLM)technique.As a cathode,the obtained 3D-MoS_(2)/Ni could maintain a degradation rate above 94.0%for forfenicol(FLO)when repeatedly used 50 times in water.We also found that the removal rate of FLO by 3D-MoS_(2)/Ni was about 12 times higher than that of 3D-printed pure Ni(3D-Ni),attributed to the improved accessibility of H^(*).In addition,the electrochemical characterization results showed that the electrochemically active surface area of the 3D-MoS_(2)/Ni electrode is about 3-fold higher than that of the 3D-Ni electrode while the electrical resistance is 4 times lower.Based on tert-butanol suppression,electron paramagnetic resonance and triple quadrupole mass spectrometer experiments,a“dual path”mechanism and possible degradation pathway for the dechlorination of FLO by 3D-MoS_(2)/Ni were proposed.Furthermore,we also investigated the impacts of the cathode potential and the initial pH of the solution on the degradation of FLO.Overall,this study reveals that the SLM 3D printing technique is a promising approach for the rapid fabrication of high-stability metal electrodes,which could have broad application in the control of water contaminants in the environmental field.
文摘In the current study poly(lactic acid)PLA composites with a 3 wt%and 5 wt%of nanofibrillated cellulose(NFC)were produced by 3D-printing method.An enzymatic pretreatment coupled with mechanical fibrillation in a twin screw extruder was used to produce high consistency NFC.Scanning electron microscopy(SEM)equipped with Fibermetric software,FASEP fiber length distribution analysis,Furrier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),tensile tests,impact tests and differential scanning calorimetry were used to characterize NFC and PLA/NFC composites.The results of the fiber length and width measurements together with the results of the SEM analysis showed that enzymatic hydrolysis coupled with a twin screw extrusion could effectively reduce the diameter and length of cellulose fibers.The produced NFC consisted of microand nanosized fibers entangled in a characteristic 3D-network.Based on the FT-IR analysis,no new bonds were formed during the enzymatic hydrolysis or fibrillation process.The TGA analysis confirmed that produced NFC can be used in hightemperature extrusion processing without NFC degradation.During the PLA/NFC composites preparation the NFC agglomerates were formed,which negatively influenced PLA/NFC composites impact properties.The slightly improved tensile strength and elastic modulus were reported for all composites when compared to the neat PLA.The elongation at break was not affected by the NFC addition.No significant differences in thermal stability were detectable among composites nor in comparation with the neat PLA.However,the crystallinity degree of the composite containing 5 wt%NFC was increased in respect to the neat PLA.
基金sponsored by the National Science Foundation of China(Nos.32071341,52202358,52003302)The Natural Science Foundation of Guangdong Province(No.2017A030308004)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110824)the Science and Technology Project of Guangdong province(No.2018A050506021).
文摘The architecture and surface modifications have been regarded as effective methods to enhance the bi-ological response of biomaterials in bone tissue engineering.The porous architecture of the implanta-tion was essential conditions for bone regeneration.Meanwhile,the design of biomimetic hydroxyap-atite(HAp)coating on porous scaffolds was demonstrated to strengthen the bioactivity and stimulate osteogenesis.However,bioactive bio-ceramics such asβ-tricalcium phosphate(β-TCP)and calcium sili-cate(CS)with superior apatite-forming ability were reported to present better osteogenic activity than that of HAp.Hence in this study,3D-printed interconnected porous bioactive ceramicsβ-TCP/CS scaf-fold was fabricated and the biomimetic HAp apatite coating were constructed in situ via hydrothermal reaction,and the effects of HAp apatite layer on the fate of mouse bone mesenchymal stem cells(mBM-SCs)and the potential mechanisms were explored.The results indicated that HAp apatite coating en-hanced cell proliferation,alkaline phosphatase(ALP)activity,and osteogenic gene expression.Further-more,PI3K/AKT/mTOR signaling pathway is proved to have an important impact on cellular functions.The present results demonstrated that the key molecules of phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT)and mammalian target of rapamycin(mTOR)were activated after the biomimetic hydrox-yapatite coating were constructed on the 3D-printed ceramic scaffolds.Besides,the activated influence on the protein expression of Runx2 and BMP2 could be suppressed after the treatment of inhibitor HY-10358.In vivo studies showed that the constructed HAp coating promoted bone formation and strengthen the bone quality.These results suggest that biomimetic HAp coating constructed on the 3D-printed bioac-tive composite scaffolds could strengthen the bioactivity and the obtained biomimetic multi-structured scaffolds might be a potential alternative bone graft for bone regeneration.
基金Project(2021RC3003) supported by the Hunan Science and Technology Innovation Talents Program,China。
文摘The present investigation introduces a composite frequency selective Rasorber(CFSR)that demonstrates a wide−1 dB transmission band,two high absorption bands with absorptivity higher than 90%,and large oblique incidence angles up to 60°.The CFSR consists of four functional layers separated by three dielectric slabs,which includes lossless metasurface-Ⅰ(MS-Ⅰ),loss metasurface-Ⅱ(MS-Ⅱ),loss metasurface-Ⅲ(MS-Ⅲ),and a three-dimensional metastructure(3D-MS).MS-Ⅰfunctions as a reflector for two absorption bands with a minimal insertion loss transmission window.MS-Ⅱis designed for high-frequency absorption.MS-Ⅲserves as a low-frequency absorption layer for CFSR and an impedance matching layer for MS-Ⅱ.The design methodologies for the transmission window in MS-III and the introduction of 3D-MS are key to achieving high-performance CFSR.The physical mechanisms of CFSR are explained through equivalent circuit model(ECM)analysis and impedance characterization.Finally,measurement results confirm that the proposed CFSR exhibits a−1 dB transmission band ranging from 8.79 to 10.41 GHz with a minimum insertion loss of 0.44 dB at 9.59 GHz;furthermore,the frequency range where reflection coefficient remains below−10 dB is measured to be between 3.33 and 18.00 GHz,aligning well with simulation outcomes.
基金funded by the China Postdoctoral Science Foundation(No.2019M663487)the National Key Research and Development Program of China(No.2022YFE03130000)。
文摘A liquid Li divertor is a promising alternative for future fusion devices.In this work a new divertor model is proposed,which is processed by 3D-printing technology to accurately control the size of the internal capillary structure.At a steady-state heat load of 10 MW m^(-2),the thermal stress of the tungsten target is within the bearing range of tungsten by finite-element simulation.In order to evaluate the wicking ability of the capillary structure,the wicking process at 600℃ was simulated by FLUENT.The result was identical to that of the corresponding experiments.Within 1 s,liquid lithium was wicked to the target surface by the capillary structure of the target and quickly spread on the target surface.During the wicking process,the average wicking mass rate of lithium should reach 0.062 g s^(-1),which could even supplement the evaporation requirement of liquid lithium under an environment>950℃.Irradiation experiments under different plasma discharge currents were carried out in a linear plasma device(SCU-PSI),and the evolution of the vapor cloud during plasma irradiation was analyzed.It was found that the target temperature tends to plateau despite the gradually increased input current,indicating that the vapor shielding effect is gradually enhanced.The irradiation experiment also confirmed that the 3D-printed tungsten structure has better heat consumption performance than a tungsten mesh structure or multichannel structure.These results reveal the application potential and feasibility of a 3D-printed porous capillary structure in plasma-facing components and provide a reference for further liquid-solid combined target designs.
基金supported by the China Scholarship Council(No.202006120422)the National Natural Science Foundation of China(Nos.51874110,51604089)+5 种基金Natural Science Foundation of Heilongjiang Province(No.LH2021B011)Open Project of State Key Laboratory of Urban Water Resource and Environment(No QA202138)the support by the Singapore Ministry of Education(MOE,No.MOE2018-T2-2-095)for research conducted at the National University of Singaporethe Green Energy Programme(No.R284-000-185-731)funded by the National University of Singapore。
文摘Sodium(Na)metal batteries have gained increasing attention more recently,owing to their high energy densities and cost efficiencies,but are severely handicapped by the unsatisfactory Coulombic efficiency(CE)and cycling stability stemming from dendrite growth on Na anodes.In this study,we developed a strategy of direct ink writing(DIW)3D printing combined with electroless deposition to construct a hierarchical Cu grid coated with a dense nanoscale Ag interfacial layer as the host material for Na plating.The sodiophilic Ag interface contributes to a fall in the Na nucleation energy,hence enabling uniform Na deposition on each 3D-printed filament.The constructed 3D-printed structure can effectively moderate the electric-field distribution and lower the local current density for relieving Na inhomogeneous growth,as confirmed by finite element simulation and Na plating/stripping morphology evolution results.In particular,the unique 3D structure also promotes the lateral growth of Na,thus the volume change of Na metal was accommodated to stabilize the solid electrolyte interphase(SEI).As a result,the CE of the half-cell can reach 99.9%at the current density of 1 m A/cm^(2)after 300 cycles and the full-cell exhibits outstanding electrochemical performance(capacity retention of 91.0%after 500 cycles at 2 C).
文摘In this work,we reported a series of monolithic 3D-printed Ni-Mo alloy electrodes for highly efficient water splitting at high current density(1500 mA cm^(-2))with excellent stability,which provides a solution to scale up Ni-Mo catalysts for HER to industry use.All possible Ni-Mo metal/alloy phases were achieved by tuning the atomic composition and heat treatment procedure,and they were investigated through both experiment and simulation,and the optimal NiMo phase shows the best performance.Density functional theory(DFT)calculations elucidate that the NiMo phase has the lowest H2O dissociation energy,which further explains the exceptional performance of NiMo.In addition,the microporosity was modulated via controlled thermal treatment,indicating that the 1100℃sintered sample has the best catalytic performance,which is attributed to the high electrochemically active surface area(ECSA).Finally,the four different macrostructures were achieved by 3D printing,and they further improved the catalytic performance.The gyroid structure exhibits the best catalytic performance of driving 500 mA cm^(-2)at a low overpotential of 228 mV and 1500 mA cm^(-2)at 325 mV,as it maximizes the efficient bubble removal from the electrode surface,which offers the great potential for high current density water splitting.
基金This study was supported by the Education Department of Hainan Province(HnjgY2022-12)Hainan Provincial Natural Science Foundation of China(320CXTD437 and 2019RC189)+1 种基金the National Natural Science Foundation of China(32260127 and 31672303)to CYthe Hainan Provincial Innovative Research Program for Graduates(Qhyb2021-55)to XC.
文摘Living and/or non-living animal models are often used as stimuli to observe the behavioral responses of the target animals.In the past,parasites,predators,and harmless controls have been used to test host anti-parasitism defense behavior,and their taxidermy specimens have been widely used as a set of standard methods for the study of avian brood parasitism.In recent years,with the rapid development of 3D-printing technology,3D-printed bird models are expected to be applied as a standard method in the study of avian brood parasitism.To evaluate the use of 3D-printed models,this study tests the reaction of Oriental Reed Warbler(Acrocephalus orientalis)towards predators,parasites,or controls,and compares the reaction among different nest intruders and between taxidermy specimens and 3D-printed animal models.It was found that the Oriental Reed Warbler responded most aggressively to the parasite,followed by predator,and finally the control;the results were consistent between the reaction to taxidermy specimens and 3D-printed animal models,indicating that 3D-printed models could serve as a substitute for taxidermy specimens.We propose a series of advantages of using 3D-printed models and suggest them to be a standard method for widespread use in future studies of avian brood parasitism.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51373048)the National Key Research and Development Program of China(Grant Nos.U1604253 and 2016YFB0101602)
文摘To improve the strength of carbon fiber(CF) reinforced Polycaprolactam(PA6) composites, controlled amounts of carbon nanotubes(CNTs) were grafted onto the surface of CF to prepare the hybrid reinforcement(HR). We used HR to fabricate laminate and H-sample to test the interfacial bonding strength(IBS) of the composites by means of a novel process called three-dimensional printed molding(3 D-PM). By using the melt drop printing method, we measured the contact angles between PA6 and CF(without sizing) and between PA6 and HR. The IBS and the mechanical properties of the composites were obtained by the tensile test. The experimental result indicated that CF grafted by 0.25% weight fraction of CNT or more could develop a special microstructure similar to the micro-pits on the surface of CF, which improved the wettability of CF and PA6 due to the increased surface area and the roughness of CF. When the weight fraction of CNT reached 0.25%, the IBS increased by 41.8%, the tensile strength by 130%, and the interfacial shear strength(IFSS) by 238%. The interfacial dimple fracture was observed by Scanning Electron Microscope(SEM), which revealed that the composites were able to absorb more deforming energy before fracture. The modified surface microstructure of CF would prevent crack propagation at the interface and increase the mechanical properties of thermoplastic composites(TPCs).
基金the Technology Project of Shanghai Science and Technology Commission(Nos.19441902700 and 18441903100)the Clinical Research Plan of SHDC(No.SHDC2020CR3083B)the Shanghai Municipal Education Commission(No.20152221)。
文摘The study aimed to explore the feasibility of an image registration technique for assessing the accuracy of intraoperative osteotomy of pelvic tumors by 3-dimensional(3D)-printed patient-specific templates.Patients with malignant pelvic tumors who were admitted to our hospital between March 2014 and December 2020 were retrospectively enrolled.Patients underwent hemi-pelvic resection and reconstruction by 3D-printed individualized prostheses.The registration between the designed model and the postoperative segmented model of the prosthesis was used to obtain the intraoperative osteotomy plane and reduce metal artifacts in postoperative computed tomography(CT)images.The distance and angle between the planned and actual osteotomy planes were then used to assess the accuracy of the intraoperative osteotomy.Eight patients with 13 osteotomy planes were enrolled,including four males and four females.The median age at the time of imaging examination was 44 years(range,33–54 years).All intraoperative osteotomy planes were assessed successfully.The mean distance between the planned and true intraoperative osteotomy planes was−0.69 cm(−7.5–7.35 cm),and the mean angle was 6.57°±3.36°(1.05°–11.88°).This new assessment method of registering the designed model and the postoperative CT segmented model of the prosthesis may be used to assess the accuracy of intraoperative osteotomy for pelvic tumors,using 3D printed patient-specific templates.
基金the Clinical Research Program of 9th People’s Hospital,Shanghai Jiao Tong University School of Medicine(No.JYLJ015)the Clinical Research Plan of SHDC(No.16CR3099B)+1 种基金the National Key Research and Development Program of China(No.2017YFC1103900)the Class IV Peak Subject Program of Shanghai Jiao Tong University School of Medicine(No.GXQ03)。
文摘Osteochondral lesion of the talus(OLT)is a common cause of ankle pain that often occurs in the talar dome and leads to talar cartilage and subchondral bone damage.Osteochondral autograft transplantation is a logical treatment option.It is known that if the cartilage does not heal properly after injury,it degenerates,and osteoarthritis worsens.A three dimensional(3D)-printed guide plate can be used to find the curved articular surface from the donor site which optimally fits the defect in the talus.Herein,we present the case of a 28-year-old man who had an open injury from the crash of a tricycle in the right ankle at the age of 5.Radiographs revealed a large defect in the medial talar dome that affected nearly half of the talar dome.We performed the debridement of the ankle lesion.An osteochondral autograft was harvested from the medial femoral condyle(MFC)with the help of a personalised 3D-printed guide plate.This 3D-printed guide plate simulated the contour of a specific area in the talar dome,which involved the site of the defect.The autograft was then transplanted into the talus defect.The efficacy of this technique was evaluated at 2,4,and 7 months after surgery and proven to be reliable.
基金the Natural Science Foundation of Zhejiang Province(Grant No.LR19E090001)the Natural Science Foundation of China(Grant Nos.42077252,42011530122,and 51979272).
文摘Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically investigated.Three physical models of DFNs were 3D-printed and then computed tomography(CT)-scanned to obtain the specific geometry of fractures.The validity of numerically simulating the fluid flow through DFNs was verified via comparison with flow tests on the 3D-printed models.A parametric study was then implemented to establish quantitative relations between the coefficients/parameters in Forchheimer’s law and geometrical parameters.The results showed that the 3D-printing technique can well reproduce the geometry of single fractures with less precision when preparing complex fracture networks,numerical modeling precision of which can be improved via CT-scanning as evidenced by the well fitted results between fluid flow tests and numerical simulations using CT-scanned digital models.Streamlines in DFNs become increasingly tortuous as the fracture number and roughness increase,resulting in stronger inertial effects and greater curvatures of hydraulic pressure-low rate relations,which can be well characterized by the Forchheimer’s law.The critical hydraulic gradient for the onset of nonlinear flow decreases with the increasing aperture,fracture number and roughness,following a power function.The increases in fracture aperture and number provide more paths for fluid flow,increasing both the viscous and inertial permeabilities.The value of the inertial permeability is approximately four orders of magnitude greater than the viscous permeability,following a power function with an exponent a of 3,and a proportional coefficient b mathematically correlated with the geometrical parameters.
基金supported by the Sichuan Science and Technology Program (Nos.2019JDTD0008 and 2022YFG0109)the China Postdoctoral Science Foundation (Nos.2021M692316 and 2020TQ0218).
文摘Titanium(Ti)and its alloys have been extensively explored for treating load-bearing bone defects.How-ever,high-stress shielding,weak osteogenic activity,and insufficient vascularization remain key chal-lenges for the long-term clinical outcomes of Ti-based implants.Herein,inspired by structural and func-tional cues of bone regeneration,a silicon-doped nano-hydroxyapatite(nSiHA)/titanium dioxide(TiO_(2))composite coating with a hierarchical micro/nano-network structure is constructed on the surface of a 3D-printed porous Ti scaffold via a combined strategy of acid-alkali(AA)treatment and electrochemi-cal deposition technique,which not only endows the scaffold with excellent osteoinduction ability but can also effectively immobilize and release vascular endothelial growth factor(VEGF).The results of the in vitro cell experiments show that the functionalized Ti scaffold significantly promotes osteogenesis in bone marrow mesenchymal stem cells(BMSCs)and angiogenesis in human umbilical vein endothelial cells(HUVECs)by activating the extracellular signal-regulated protein kinase(ERK)and HIF-1αsignaling pathways.After being implanted into a rat femoral condyle defect model,the functionalized Ti scaffold can induce in situ vascularized bone regeneration by orchestrating the two coupled processes of angio-genesis and osteogenesis.These findings indicate that the functionalized Ti scaffold has great potential in bone tissue regeneration and is a promising candidate for load-bearing bone defect repair.
基金supported by the Fund of Natural Science Foundation of China(No.11872196,12232005)supported by the Outstanding Postgraduate‘Innovation Star’Fund for Distinguished of Gansu Province(No.2021CXZX-032).
文摘Superconducting YBa_(2)Cu_(3)O_(7−x)(YBCO)bulks have promising applications in quasi-permanent magnets,levitation,etc.Recently,a new way of fabricating porous YBCO bulks,named direct-ink-writing(DIW)3D-printing method,has been reported.In this method,the customized precursor paste and programmable shape are two main advantages.Here,we have put forward a new way to customize the YBCO 3D-printing precursor paste which is doped with Al_(2)O_(3)nanoparticles to obtain YBCO with higher thermal conductivity.The great rheological properties of precursor paste after being doped with Al_(2)O_(3)nanoparticles can help the macroscopic YBCO samples with high thermal conductivity fabricated stably with high crystalline and lightweight properties.Test results show that the peak thermal conductivity of Al_(2)O_(3)-doped YBCO can reach twice as much as pure YBCO,which makes a great effort to reduce the quench propagation speed.Based on the microstructure analysis,one can find that the thermal conductivity of Al_(2)O_(3)-doped YBCO has been determined by its components and microstructures.In addition,a macroscopic theoretical model has been proposed to assess the thermal conductivity of different microstructures,whose calculated results take good agreement with the experimental results.Meanwhile,a microstructure with high thermal conductivity has been found.Finally,a macroscopic YBCO bulk with the presented high thermal conductivity microstructure has been fabricated by the Al_(2)O_(3)-doped method.Compared with YBCO fabricated by the traditional 3D-printed,the Al_(2)O_(3)-doped structural YBCO bulks present excellent heat transfer performances.Our customized design of 3D-printing precursor pastes and novel concept of structural design for enhancing the thermal conductivity of YBCO superconducting material can be widely used in other DIW 3D-printing materials.
基金supported by a grant from the Ministry of Research, Innovation and Digitization, UEFISCDI, Grant Nos. PN-IIIP2-2.1-PED-2021-1890, PN-IV-P6-6.3-SOL-2024-2-0254 and PNIV-P7-7.1-PTE-2024-0517, within PNCDI Ⅳ.
文摘This study represents an important step forward in the domain of additive manufacturing of energetic materials.It presents the successful formulation and fabrication by 3D printing of gun propellants using Fused Deposition Modeling(FDM)technology,highlighting the immense potential of this innovative approach.The use of FDM additive manufacturing technology to print gun propellants is a significant advancement due to its novel application in this field,which has not been previously reported.Through this study,the potential of FDM 3D-printing in the production of high-performance energetic composites is demonstrated,and also a new standard for manufacturability in this field can be established.The thermoplastic composites developed in this study are characterized by a notably high energetic solids content,comprising 70%hexogen(RDX)and 10%nitrocellulose(NC),which surpasses the conventional limit of 60%energetic solids typically achieved in stereolithography and light-curing 3D printing methods.The primary objective of the study was to optimize the formulation,enhance performance,and establish an equilibrium between printability and propellant efficacy.Among the three energetic for-mulations developed for 3D printing feedstock,only two were suitable for printing via the FDM tech-nique.Notably,the formulation consisting of 70%RDX,10%NC,and 20%polycaprolactone(PCL)emerged as the most advantageous option for gun propellants,owing to its exceptional processability,ease of printability,and high energetic performance.
基金the financial support for this work from the National Natural Science Foundation of China(Nos.52171241,52373251,52201301,51801137)Natural Science Foundation of Tianjin City,China(No.22JCQNJC00750)Tianjin University of Technology Graduate Research Innovation Project,China(No.YJ2235)。
文摘The Mg−1Zn−1Sn and Mg−1Zn−1Sn−0.2Ca alloy scaffolds were prepared via infiltration casting using 3D-printed Ti templates to achieve complete and accurate control of the pore structure.The results indicate that the actual porosity and pore size of the prepared P model for each pore size are greater than the designed values.The addition of Ca changes the second phase of the alloy from Mg_(2)Sn to CaMgSn and refines its microstructure.The compressive yield strength and compressive modulus of the Mg−1Zn−1Sn−0.2Ca alloy scaffold reach 32.61 MPa and 0.23 GPa,respectively.The corrosion current density is measured at 14.64μA/cm^(2),with an instantaneous corrosion rate of 0.335 mm/a.Both scaffolds exhibit excellent biocompatibility and no cytotoxicity.Additionally,the antibacterial effects of both alloys on E.coli are greater than 97.81%.These results indicate that Mg alloy scaffolds have great potential for clinical applications.