Laser directed energy deposition(LDED)is an emerging branch of metal-based additive manufacturing(AM)processes,offering unprecedented capabilities for high-performance fabrication with complex geometries and near-net ...Laser directed energy deposition(LDED)is an emerging branch of metal-based additive manufacturing(AM)processes,offering unprecedented capabilities for high-performance fabrication with complex geometries and near-net shapes.This technology is gathering increasing attention from industries such as biomedical,automotive,and aerospace.However,achieving consistent part quality and desired material properties is challenging due to intricate processing parameters and potential process defects such as dynamic melt-pool behavior and localized heat accumulation.This paper reviews recent advances in on-line quality control,focusing on in-situ measurement and closed-loop control for efficient assurance of LDED-fabricated parts.The quality principles,encompassing accuracy and material performance,are summarized to lay a foundation for understanding the mechanisms of quality defects and influencing factors.This review explores and thoroughly compares advancements in indirect process measurements,such as optical,thermal,and acoustic monitoring with direct quality measurements,including laser-line scanning and operando synchrotron X-ray imaging.Depending on the sensing techniques,this paper highlights a hierarchical control strategy for adaptive parameter regulation on intra-layer and inter-layer scales.The requirements and performance of various state-of-the-art controllers are critically compared to indicate their suitable applications.The importance of machine learning in detecting process anomalies and predicting build quality based on sensory signals is also outlined.Future directions are proposed towards adaptive,automated,and intelligent quality control,with a focus on multi-modal monitoring,physics-informed neural networks for interpretable analysis,and multi-objective control applications.展开更多
Rechargeable aqueous zinc-ion batteries(AZIBs)are widely studied for energy storage because of their high safety,low cost and high energy/power density.However,the practical application of AZIBs is limited by dendrite...Rechargeable aqueous zinc-ion batteries(AZIBs)are widely studied for energy storage because of their high safety,low cost and high energy/power density.However,the practical application of AZIBs is limited by dendrite formation at the zinc anode under high-depth deposition,which results in reduced cycle life and overall performance.Herein,we propose an effective and scalable stepwise deposition approach that integrates uniform nucleation and dense growth through the construction of ultrathin ZnO nanofiber arrays(ZONAs)on the zinc anode surface,along with the introduction of an anionic surfactant(AS)into the electrolyte.This approach yields a uniform,dense and dendrite-free Zn anode during cycling,maintaining stable cycling for 2100 h under a high deposition depth of 10 mAh cm^(-2)at an extremely high current density of 10 m A cm^(-2).Additionally,full cells using MnO_(2)cathodes exhibit stable cycling for 6000cycles at 5 A g^(-1),with a capacity retention of 75%.Furthermore,the pouch-type cell with an area of90 cm2delivers a capacity of 60 m Ah and maintains stable cycling for 540 cycles at 200 mA,highlighting its strong potential for scalability.展开更多
Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological me...Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal imbalances.IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic diseases.Although imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes.Currently,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease.This paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD.展开更多
Aqueous zinc-ion electrochromic(EC)technology,boasting the capability to fulfill both safety and cost-ef⁃fectiveness requirements,is garnering extensive attention in various application areas including smart windows,t...Aqueous zinc-ion electrochromic(EC)technology,boasting the capability to fulfill both safety and cost-ef⁃fectiveness requirements,is garnering extensive attention in various application areas including smart windows,thermal management,displays,and camouflage.However,typical inorganic EC materials,such as tungsten oxides(WO_(3)),of⁃ten suffer from slow ion diffusion kinetics and limited optical contrast within the aqueous Zn^(2+)electrolyte because of the large size and strong Coulombic interactions of the Zn^(2+),which limits their wide applicability.Here,ordered WO_(3)nanowire films,constructed by a one-step grazing angle deposition method,is demonstrated to boost the response speed and optical contrast during EC phenomena.Compared with dense films,the ordered WO_(3)nanowire films with a porosity of 44.6%demonstrate anti-reflective property and excellent comprehensive EC performance,including fast response time(3.6 s and 1.2 s for coloring and bleaching,respectively),large optical contrast(66.6%at 700 nm)and high col⁃oration efficiency(64.3 cm^(2)·C^(-1)).A large-area prototype EC device(17 cm×12 cm)with fast color-switching is also successfully achieved.Mechanistic studies show that the improved performance is mainly due to the ordered porous nanowire structures,which provides direct electron transfer paths and sufficient interfacial contacts,thus simultaneously enhancing the electrochemical activity and fast redox kinetics.This study provides a simple and effective strategy to im⁃prove the performance of tungsten oxide-based aqueous zinc ion EC materials and devices.展开更多
The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of indust...The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of industrial areas.In this study,two components composed of ERCuAl-A2 aluminum bronze(CuAl9)and Inconel 718 nickel-based superalloy were fabricated with different deposition orders by wire-arc directed energy deposition.Subject to changes in heat input and thermophysical properties of the substrate,the transition region of the deposited Cu-Ni component with the bottom half of CuAl9 and the top half of Inconel 718 is narrow and serrated.This region features a laminated intermetallic compound layer due to the convection and rapid cooling in the molten pool.In contrast,the Ni-Cu component deposited in the opposite order exhibits a 2 mm gradient transition zone.Within this region,a large number of diverse precipitates were found as well as regional variations in grain size due to the multi-layer partial remelting.Both two components show strong bonds and their tensile specimens tested along the vertical direction always fracture at the softer CuAl9 side.Excellent tensile properties along the horizontal direction were obtained for Cu-Ni(Ultimate tensile strength:573 MPa,yield stress:302 MPa,elongation:22%),while those of Ni-Cu are much lower due to the existence of the solidification cracks in the transition zone.The results from this study provide a reference for the additive manufacturing of Cu/Ni dissimilar alloy components,as well as their microstructure and mechanical properties control.展开更多
The unique structure and formation mechanism of medium-entropy alloys(MEAs)generally result in bet-ter comprehensive properties than traditional alloys.However,the strength-ductility trade-offremains a bottleneck,whic...The unique structure and formation mechanism of medium-entropy alloys(MEAs)generally result in bet-ter comprehensive properties than traditional alloys.However,the strength-ductility trade-offremains a bottleneck,which limits their applications.In this study,we designed novel high-performance CrNiCu x MEAs with a heterophase composition by incorporating a Cu-rich phase,and they were fabricated using laser-directed energy deposition(LDED).The results show that synergistic strengthening from multiple phases significantly improved the mechanical properties of the alloys,resulting in a tensile strength of 675 MPa and a ductility of 34.4%,demonstrating an excellent combination of high tensile strength and ductility.The improved mechanical properties of the CrNiCu x medium-entropy alloys are primarily due to the heterophase interfacial strengthening mechanism.In the alloy,numerous semi-coherent and coher-ent interfaces formed between the Cr-rich phase,Cu-rich phase,and the matrix,creating extensive lattice distortions at the interfaces.An increase in the Cu-rich phase content promoted the interaction between phases,enhancing the strain energy of the alloy and the barrier strength of the interfaces.The calcu-latedτint values,ranging from approximately 5.92-6.69 GPa,are significantly higher than those found in traditional alloys,providing a benchmark for designing new high-performance medium-entropy alloys.展开更多
Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in thi...Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in this study.The microstructure of the WE43 and CNTs/WE43 layers was systematically compared.The dissolution of divorced eutectics at the grain boundaries was retarded by CNTs during solution treatment.The spot segregation composed of Mg_(24)Y_(5),CNTs,and Zr cores in the solution treated CNTs/WE43 layer presented a slight decreasing in Y content.The grain growth of both types of layers underwent three stages:slow,rapid,and steady-state.The significant inhibitory effect of CNTs on the grain growth of the LDED WE43 matrix was more pronounced than the promoting effect of temperature,resulting in a 47%increase at 510℃ and a 35%increase at 540℃ in the grain growth exponent compared to the WE43 layers at 510℃.During the subsequent aging treatment at 225℃,the precipitation sequences from plate-shaped β″to plate-shaped and globular β′ were observed in both types of layers.CNTs can facilitate an increase in the nucleation rate of precipitates,but without accelerating precipitation hardening rate.The long and short diameters of the precipitates in peak-aged state were decreased by 48.5%and 43.1%by addition of CNTs,respectively.The wear resistance of both the WE43 and CNTs/WE43 layers can be significantly enhanced through solution and aging treatment.The enhancement in wear resistance for the CNTs/WE43 layers is considerably greater than that of the WE43 layers.展开更多
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po...Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters.展开更多
Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous Si...Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.展开更多
Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aq...Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.展开更多
Lake ecosystems are extremely sensitive to nitrogen growth,which leads to water quality degradation and ecosystem health decline.Nitrogen depositions,as one of the main sources of nitrogen in water,are expected to cha...Lake ecosystems are extremely sensitive to nitrogen growth,which leads to water quality degradation and ecosystem health decline.Nitrogen depositions,as one of the main sources of nitrogen in water,are expected to change under future climate change scenarios.However,it remains not clear how nitrogen deposition to lakes respond to future meteorological conditions.In this study,a source-oriented version of Community Multiscale Air Quality(CMAQ)Model was used to estimate nitrogen deposition to 263 lakes in 2013 and under three RCP scenarios(4.5,6.0 and 8.5)in 2046.Annual total deposition of 58.2 Gg nitrogen was predicted for all lakes,with 23.3 Gg N by wet deposition and 34.9 Gg N by dry deposition.Nitrate and ammonium in aerosol phase are the major forms of wet deposition,while NH3 and HNO_(3)in gas phase are the major forms of dry deposition.Agriculture emissions contribute to 57%of wet deposition and 44%of dry deposition.Under future meteorological conditions,wet deposition is predicted to increase by 5.5%to 16.4%,while dry deposition would decrease by 0.3%to 13.0%.Changes in wind speed,temperature,relative humidity(RH),and precipitation rates are correlated with dry and wet deposition changes.The predicted changes in deposition to lakes driven by meteorological changes can lead to significant changes in aquatic chemistry and ecosystem functions.Apart from future emission scenarios,different climate scenarios should be considered in future ecosystem health evaluation in response to nitrogen deposition.展开更多
The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-pli...The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-plication.The introduction of a porous structure in bulk thermoelectric materials has been theoretically proven to effectively reduce thermal conductivity and cost.However,the electrical properties of highly porous materials are considerably suppressed due to the strong carrier scattering at the interface be-tween the matrix and pores,ultimately leading to decreased figure of merit,ZT.Here,we use an atomic layer deposition strategy to introduce some hollow glass bubbles with nano-oxide layers into commercial Bi_(0.5)Sb_(1.5)Te_(3)for preparing high-performance porous thermoelectric materials.Experimental results indi-cate that the nano-oxide layers weaken carrier scattering at the interface between pores and matrix while maintaining high-strength phonon scattering,thereby optimizing carrier/phonon transport behaviors,and effectively increasing the ZT by 23.2%(from 0.99 to 1.22 at 350 K).Besides,our strategy has excellent universality confirmed by its effectiveness in improving the ZT of Bi_(2)Te_(2.7)Se_(0.3),therefore demonstrating great potential for developing low-cost and high-performance thermoelectric materials.展开更多
Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,m...Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,methylammonium acetate(MAAc)ionic liquid has been developed as an alternative to fabricate ideal bandgap MAPb_(0.7)Sn_(0.3)I_(3)(1.36 eV)film via hot-casting in air.However,the spontaneous crystallization of Pb-Sn perovskite initiated by heat-induced supersaturation is fast and random,setting critical challenges in regulating crystal growth during the film-forming process.Herein,a lattice activation strategy is developed to control the crystallization dynamics of MAPb_(0.7)Sn_(0.3)I_(3)in MAAc to produce films with micrometer-sized grains in air.FA is shown to activate the crystal lattice that facilitates the formation of intermediates and balances the crystal growth of MAPb_(0.7)Sn_(0.3)I_(3),producing films with a grain size of 2.78±0.17μm.Furthermore,4-fluoro-phenethylammonium and phenethylammonium are adopted to passivate the defects in the film and promote the energy level alignment at the top interface,respectively.The optimized PSC device achieved an efficiency of 18.24%with a short-circuit current of 29.84 mA/cm^(2),which are both the highest values in 1.36 eV Pb-Sn PSCs to date.Notably,the unencapsulated devices show excellent storage and air stability under various conditions.展开更多
Fragmentation is a common phenomenon in the runout process of large rockslides.Rocks have different strengths under the influence of the rock type and weathering degree,resulting in varying fragmentation characteristi...Fragmentation is a common phenomenon in the runout process of large rockslides.Rocks have different strengths under the influence of the rock type and weathering degree,resulting in varying fragmentation characteristics.However,the limited understanding of how rock strength influences the postfragmentation kinematic characteristics of rockslides is limited.Taking a natural rockslide as an example,this paper quantitatively analyzes the runout and deposition of the rockslide using the discrete element method(DEM)and examines the impacts of the rock strength on the runout and deposition characteristics of the rockslide.The results reveal that(1)Rock strength significantly influences fragmentation and runout characteristics:medium-to-high strength rocks exhibit two-stage fragmentation(10-20 s and 55-65 s),while weak-strength rocks achieve 98%fragmentation within 20 s.Optimal kinetic energy conversion occurs in medium-strength rocks,with a maximum velocity difference of 39.3 m/s between the anterior and posterior edges.(2)The sudden change in the cross-sectional dimensions of high-strength rocks under a high spreading velocity(>60 m/s)may amplify air blast hazards.(3)Deposition patterns reveal that the spatial distribution of fragments preserves original positional order;high-strength rocks produce larger fragments(nominal fragment size increases from 0.028 of weak-strength rocks to 0.607);and centroid displacement increases from 1907 m to 2117 m with rock strength in open terrains.(4)Energy dissipation analysis shows that frictional dissipation(>60%)>collisional dissipation(~37%)>>fragmentation dissipation(<2%)in the process of rockslide runout.The rock strength induces<5%variation in partitioning of energy dissipation.展开更多
Viruses, notably airborne viruses, are difficult to collect and detect because of the low concentrations of environmental microorganisms. Bacteriophages are frequently used in air experiments as suitable surrogates fo...Viruses, notably airborne viruses, are difficult to collect and detect because of the low concentrations of environmental microorganisms. Bacteriophages are frequently used in air experiments as suitable surrogates for human and animal viruses^([1]). Bacteriophages are non-pathogenic, so they are safe for laboratory workers and do not require specialized biological protection measures.Bacteriophages can be prepared at high titers using simple and low-cost methods.展开更多
The use of additive manufacturing techniques in the development of unconventional materials can help reduce the environmental impact of traditional construction materials.In this paper,the properties of a 3D-printed b...The use of additive manufacturing techniques in the development of unconventional materials can help reduce the environmental impact of traditional construction materials.In this paper,the properties of a 3D-printed biocomposite were evaluated.Biofilaments obtained by mixing pulverized bamboo fibers with polylactic acid(PLA)resin were extruded during the manufacturing process.To assess the effect of incorporating plant fibers,an analysis was conducted on the morphology,elemental chemical composition,crystallinity index,principal functional groups,thermal stability,surface roughness,microhardness,density,tensile strength,elastic modulus,and strain percentage of reinforced samples.The results were comparedwith those obtained from the characterization of standard PLAfilaments(unreinforced).The fused deposition modeling(FDM)technique was employed to print biocomposite specimens.Additionally,the influence of the printing parameters(infill density,build orientation,and layer thickness)on the physical,tribological,andmechanical properties of the biocomposites was analyzed.These results were compared with those obtained for specimens printed with pure PLA.The findings indicate that incorporating 10%vegetable filler into PLA filaments enhanced the strength and stiffness of the biocomposite under axial loads.Finally,the strength of the biocomposite subjected to axial loads was compared with the standardized values for wood-plastic composites,demonstrating the feasibility of its use for non-structural purposes in civil construction.展开更多
Repairing the Ni-based superalloy component remains challenging due to the limited understanding of the role of the defect’s morphology on microstructure and related deformation responses.To address this issue,GH4099...Repairing the Ni-based superalloy component remains challenging due to the limited understanding of the role of the defect’s morphology on microstructure and related deformation responses.To address this issue,GH4099 Ni-based superalloy plate with U-shaped and V-shaped grooves was prepared and repaired by laser-directed energy deposition method using GH4099 powders.Both grooves exhibit three similar regions at the repaired interphase,which are the base metal region with equiaxed grains,repaired region with columnar or elongated equiaxed grains,and a transition region in between.High-temperature gradient in the repaired region induced a high density of substructures,and the repaired region in U-shaped grooves has an even higher temperature gradient due to fewer passes of the melted metal,which induces more metallic carbides in the subgrain boundaries and improves the tensile strength of the repaired samples.However,due to the steep side walls,local vortex might form at the bottom corner of the U-shaped groove,leaving macroscale holes and micro-cracks there.Such defects will decrease the alloy’s ductility.The relationship among groove morphology-macro-and microstructure-mechanical properties is then established,which suggesting the preferred V-shaped groove considering the flatter sidewall and more passes induced near equilibrium microstructure.展开更多
Hardness is widely regarded as a critical factor influencing the whole texture of fish flesh.The objective of this study was to elucidate the regulatory mechanism underlying muscle hardness in hybrid bream(BBTB,Megalo...Hardness is widely regarded as a critical factor influencing the whole texture of fish flesh.The objective of this study was to elucidate the regulatory mechanism underlying muscle hardness in hybrid bream(BBTB,Megalobrama amblycephala♀×Culter alburnus♂).A comparison of the physiological features of high hardness(HH)and low hardness(LH)muscle revealed that the former had higher contents of collagen I and lower muscle fiber diameter.Transcriptomic data revealed that the myofiber assembly pathway and the HIF-1 signaling pathway were activated in HH muscle.At the metabolic level,the categories of amino acids and lipids were the principal differentially abundant metabolites between the HH and LH muscle.The detection of amino acid profiles further revealed significant differences in amino acid metabolism between the HH and LH muscles,with the HH muscle having higher levels of amino acids than the LH muscle,especially hydroxypro-line(Hyp).Furthermore,through supplementation of Hyp in BBTB myoblasts,the results indicated that 0.8 mmol/L Hyp increased the proliferation,differentiation,migration,and collagen synthesis of myoblasts.Finally,BBTB was treated with Hyp intraperitoneally for 15 days.The results revealed that 0.1 g/kg Hyp significantly increased muscle hardness,myofiber density,myofibrillar protein synthesis,and HIF-1 protein content.The results obtained in this study indicated that Hyp supplementation promoted collagen synthesis and proliferation of myoblast and muscle fibers in the BBTB,which may be induced by activation of the transcription factor HIF1 and contributes to the impacts of Hyp on improvements in muscle hardness in the BBTB.展开更多
In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition...In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition(LDED).The effects of ultrasonic vibration(UV)and tempering treatment on microstructure evolution,microhardness distribution and mechanical properties of deposition layer were studied in detail.The microstructure of UV assisted LDED sample after tempering is mainly composed of tempered sorbite(TS).Due to the improvement of microstructure inhomogeneity and grains refinement,UV assisted LDED sample with tempering treatment obtains excellent mechanical properties.The ultimate tensile strength(UTS),yield strength(YS)and elongation after breaking(EL)reach 765 MPa,657 MPa and 19.5%,the increase ratios of UTS and YS are 14.5%and 33.8%while maintaining plasticity compared to original LDED sample,respectively.It is obvious that ultrasonic vibration combined with tempering is a potential and effective method to obtain uniform microstructure and excellent mechanical properties in metal laser directed energy deposition field.展开更多
Al_(0.5)CrFeNi_(2.5)high-entropy alloy(HEA)was reinforced by the small-radius Si.Al_(0.5)CrFeNi_(2.5)Six(x=0 and 0.25)HEAs were fabricated by laser melting deposition.The evolution of microstructure,nanohardness,and w...Al_(0.5)CrFeNi_(2.5)high-entropy alloy(HEA)was reinforced by the small-radius Si.Al_(0.5)CrFeNi_(2.5)Six(x=0 and 0.25)HEAs were fabricated by laser melting deposition.The evolution of microstructure,nanohardness,and wear properties of Al_(0.5)CrFeNi_(2.5)Six(x=0 and 0.25)HEAs were systematically investigated.Al_(0.5)CrFeNi_(2.5)HEA exhibits a face-centered cubic(FCC)matrix with Ni3Al-type ordered nanoprecipitates.When Si was doped,σphase and Cr-rich nanoprecipitates existed in the B2 matrix and L12 in the FCC matrix.The nanohardness was increased from 4.67 to 5.45 GPa with doping of Si,which is associated with forming the new phases and improved nanohardness of L12/FCC phases.The coefficient of friction(COF)value was reduced from 0.75 to 0.67 by adding Si.σphase and Cr-rich nanoprecipitates in B2 matrix support a decreased wear rate from 7.87×10^(-4) to 6.82×10^(-4) mm^(3)/(N m).Furthermore,the main wear mechanism of Al_(0.5)CrFeNi_(2.5)and Al_(0.5)CrFeNi_(2.5)Si0.25 HEAs is abrasive wear.展开更多
基金supported by Royal Academy of Engineering(IF2223B-125)Royal Society(IECR3213107)。
文摘Laser directed energy deposition(LDED)is an emerging branch of metal-based additive manufacturing(AM)processes,offering unprecedented capabilities for high-performance fabrication with complex geometries and near-net shapes.This technology is gathering increasing attention from industries such as biomedical,automotive,and aerospace.However,achieving consistent part quality and desired material properties is challenging due to intricate processing parameters and potential process defects such as dynamic melt-pool behavior and localized heat accumulation.This paper reviews recent advances in on-line quality control,focusing on in-situ measurement and closed-loop control for efficient assurance of LDED-fabricated parts.The quality principles,encompassing accuracy and material performance,are summarized to lay a foundation for understanding the mechanisms of quality defects and influencing factors.This review explores and thoroughly compares advancements in indirect process measurements,such as optical,thermal,and acoustic monitoring with direct quality measurements,including laser-line scanning and operando synchrotron X-ray imaging.Depending on the sensing techniques,this paper highlights a hierarchical control strategy for adaptive parameter regulation on intra-layer and inter-layer scales.The requirements and performance of various state-of-the-art controllers are critically compared to indicate their suitable applications.The importance of machine learning in detecting process anomalies and predicting build quality based on sensory signals is also outlined.Future directions are proposed towards adaptive,automated,and intelligent quality control,with a focus on multi-modal monitoring,physics-informed neural networks for interpretable analysis,and multi-objective control applications.
基金financial support from the National Natural Science Foundation of China(grant 22090060/22090063)Liaoning Province(2023-MS-014)。
文摘Rechargeable aqueous zinc-ion batteries(AZIBs)are widely studied for energy storage because of their high safety,low cost and high energy/power density.However,the practical application of AZIBs is limited by dendrite formation at the zinc anode under high-depth deposition,which results in reduced cycle life and overall performance.Herein,we propose an effective and scalable stepwise deposition approach that integrates uniform nucleation and dense growth through the construction of ultrathin ZnO nanofiber arrays(ZONAs)on the zinc anode surface,along with the introduction of an anionic surfactant(AS)into the electrolyte.This approach yields a uniform,dense and dendrite-free Zn anode during cycling,maintaining stable cycling for 2100 h under a high deposition depth of 10 mAh cm^(-2)at an extremely high current density of 10 m A cm^(-2).Additionally,full cells using MnO_(2)cathodes exhibit stable cycling for 6000cycles at 5 A g^(-1),with a capacity retention of 75%.Furthermore,the pouch-type cell with an area of90 cm2delivers a capacity of 60 m Ah and maintains stable cycling for 540 cycles at 200 mA,highlighting its strong potential for scalability.
基金Supported by National Natural Science Foundation of China,No.82170651and the Research Support Fund of Hubei Microcirculation Society,No.HBWXH2024(1)-1.
文摘Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal imbalances.IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic diseases.Although imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes.Currently,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease.This paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD.
基金Supported by Jilin Provincial Scientific and Technological Development Program(20230508109RC,20230201051GX,20220201091GX)National Natural Science Foundation of China(62035013,61275235)。
文摘Aqueous zinc-ion electrochromic(EC)technology,boasting the capability to fulfill both safety and cost-ef⁃fectiveness requirements,is garnering extensive attention in various application areas including smart windows,thermal management,displays,and camouflage.However,typical inorganic EC materials,such as tungsten oxides(WO_(3)),of⁃ten suffer from slow ion diffusion kinetics and limited optical contrast within the aqueous Zn^(2+)electrolyte because of the large size and strong Coulombic interactions of the Zn^(2+),which limits their wide applicability.Here,ordered WO_(3)nanowire films,constructed by a one-step grazing angle deposition method,is demonstrated to boost the response speed and optical contrast during EC phenomena.Compared with dense films,the ordered WO_(3)nanowire films with a porosity of 44.6%demonstrate anti-reflective property and excellent comprehensive EC performance,including fast response time(3.6 s and 1.2 s for coloring and bleaching,respectively),large optical contrast(66.6%at 700 nm)and high col⁃oration efficiency(64.3 cm^(2)·C^(-1)).A large-area prototype EC device(17 cm×12 cm)with fast color-switching is also successfully achieved.Mechanistic studies show that the improved performance is mainly due to the ordered porous nanowire structures,which provides direct electron transfer paths and sufficient interfacial contacts,thus simultaneously enhancing the electrochemical activity and fast redox kinetics.This study provides a simple and effective strategy to im⁃prove the performance of tungsten oxide-based aqueous zinc ion EC materials and devices.
基金supported by the Key Research and Development Program of Shaanxi Province(2023-YBGY361)the National Natural Science Foundation of China(52275374 and 52205414)+1 种基金the Postdoctoral Fellowship Program of CPSF(GZC20232098)as well as the Xiaomi Foundation through Xiaomi Young Scholar Program。
文摘The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of industrial areas.In this study,two components composed of ERCuAl-A2 aluminum bronze(CuAl9)and Inconel 718 nickel-based superalloy were fabricated with different deposition orders by wire-arc directed energy deposition.Subject to changes in heat input and thermophysical properties of the substrate,the transition region of the deposited Cu-Ni component with the bottom half of CuAl9 and the top half of Inconel 718 is narrow and serrated.This region features a laminated intermetallic compound layer due to the convection and rapid cooling in the molten pool.In contrast,the Ni-Cu component deposited in the opposite order exhibits a 2 mm gradient transition zone.Within this region,a large number of diverse precipitates were found as well as regional variations in grain size due to the multi-layer partial remelting.Both two components show strong bonds and their tensile specimens tested along the vertical direction always fracture at the softer CuAl9 side.Excellent tensile properties along the horizontal direction were obtained for Cu-Ni(Ultimate tensile strength:573 MPa,yield stress:302 MPa,elongation:22%),while those of Ni-Cu are much lower due to the existence of the solidification cracks in the transition zone.The results from this study provide a reference for the additive manufacturing of Cu/Ni dissimilar alloy components,as well as their microstructure and mechanical properties control.
基金supported by the National Natural Science Foundation of China(Grant No.U2341254)the National Natural Science Foundation of China(Grant No.52071124),the Natural Science Foundation of Jiangsu Province(No.BK20230502)the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB547).
文摘The unique structure and formation mechanism of medium-entropy alloys(MEAs)generally result in bet-ter comprehensive properties than traditional alloys.However,the strength-ductility trade-offremains a bottleneck,which limits their applications.In this study,we designed novel high-performance CrNiCu x MEAs with a heterophase composition by incorporating a Cu-rich phase,and they were fabricated using laser-directed energy deposition(LDED).The results show that synergistic strengthening from multiple phases significantly improved the mechanical properties of the alloys,resulting in a tensile strength of 675 MPa and a ductility of 34.4%,demonstrating an excellent combination of high tensile strength and ductility.The improved mechanical properties of the CrNiCu x medium-entropy alloys are primarily due to the heterophase interfacial strengthening mechanism.In the alloy,numerous semi-coherent and coher-ent interfaces formed between the Cr-rich phase,Cu-rich phase,and the matrix,creating extensive lattice distortions at the interfaces.An increase in the Cu-rich phase content promoted the interaction between phases,enhancing the strain energy of the alloy and the barrier strength of the interfaces.The calcu-latedτint values,ranging from approximately 5.92-6.69 GPa,are significantly higher than those found in traditional alloys,providing a benchmark for designing new high-performance medium-entropy alloys.
基金supported by the National Natural Science Foundation of China(52005264).
文摘Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in this study.The microstructure of the WE43 and CNTs/WE43 layers was systematically compared.The dissolution of divorced eutectics at the grain boundaries was retarded by CNTs during solution treatment.The spot segregation composed of Mg_(24)Y_(5),CNTs,and Zr cores in the solution treated CNTs/WE43 layer presented a slight decreasing in Y content.The grain growth of both types of layers underwent three stages:slow,rapid,and steady-state.The significant inhibitory effect of CNTs on the grain growth of the LDED WE43 matrix was more pronounced than the promoting effect of temperature,resulting in a 47%increase at 510℃ and a 35%increase at 540℃ in the grain growth exponent compared to the WE43 layers at 510℃.During the subsequent aging treatment at 225℃,the precipitation sequences from plate-shaped β″to plate-shaped and globular β′ were observed in both types of layers.CNTs can facilitate an increase in the nucleation rate of precipitates,but without accelerating precipitation hardening rate.The long and short diameters of the precipitates in peak-aged state were decreased by 48.5%and 43.1%by addition of CNTs,respectively.The wear resistance of both the WE43 and CNTs/WE43 layers can be significantly enhanced through solution and aging treatment.The enhancement in wear resistance for the CNTs/WE43 layers is considerably greater than that of the WE43 layers.
文摘Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters.
文摘Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.
基金partially supported by the National Natural Science Foundation of China(22479022)Liaoning Revitalization Talents Program(XLYC2007129)。
文摘Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.
基金supported by the project of Guangzhou Institute of Geochemistry the Chinese Academy of Sciences(No.51TGC202209)Shenzhen Science and Technology Plan(Nos.KJYY20180206180737010 and 6020320003K)the National Key R&D Program of China(No.2022YFC3701105).
文摘Lake ecosystems are extremely sensitive to nitrogen growth,which leads to water quality degradation and ecosystem health decline.Nitrogen depositions,as one of the main sources of nitrogen in water,are expected to change under future climate change scenarios.However,it remains not clear how nitrogen deposition to lakes respond to future meteorological conditions.In this study,a source-oriented version of Community Multiscale Air Quality(CMAQ)Model was used to estimate nitrogen deposition to 263 lakes in 2013 and under three RCP scenarios(4.5,6.0 and 8.5)in 2046.Annual total deposition of 58.2 Gg nitrogen was predicted for all lakes,with 23.3 Gg N by wet deposition and 34.9 Gg N by dry deposition.Nitrate and ammonium in aerosol phase are the major forms of wet deposition,while NH3 and HNO_(3)in gas phase are the major forms of dry deposition.Agriculture emissions contribute to 57%of wet deposition and 44%of dry deposition.Under future meteorological conditions,wet deposition is predicted to increase by 5.5%to 16.4%,while dry deposition would decrease by 0.3%to 13.0%.Changes in wind speed,temperature,relative humidity(RH),and precipitation rates are correlated with dry and wet deposition changes.The predicted changes in deposition to lakes driven by meteorological changes can lead to significant changes in aquatic chemistry and ecosystem functions.Apart from future emission scenarios,different climate scenarios should be considered in future ecosystem health evaluation in response to nitrogen deposition.
基金supported by the National Natural Science Foundation of China(Nos.U21A2054,21905007)the Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(Grant No.202255464).
文摘The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-plication.The introduction of a porous structure in bulk thermoelectric materials has been theoretically proven to effectively reduce thermal conductivity and cost.However,the electrical properties of highly porous materials are considerably suppressed due to the strong carrier scattering at the interface be-tween the matrix and pores,ultimately leading to decreased figure of merit,ZT.Here,we use an atomic layer deposition strategy to introduce some hollow glass bubbles with nano-oxide layers into commercial Bi_(0.5)Sb_(1.5)Te_(3)for preparing high-performance porous thermoelectric materials.Experimental results indi-cate that the nano-oxide layers weaken carrier scattering at the interface between pores and matrix while maintaining high-strength phonon scattering,thereby optimizing carrier/phonon transport behaviors,and effectively increasing the ZT by 23.2%(from 0.99 to 1.22 at 350 K).Besides,our strategy has excellent universality confirmed by its effectiveness in improving the ZT of Bi_(2)Te_(2.7)Se_(0.3),therefore demonstrating great potential for developing low-cost and high-performance thermoelectric materials.
基金financially supported by the Natural Science Foundation of China(52372226,52202300,62288102,62350013,52303325)National Key Research and Development Program of China(2023YFB3608900)+5 种基金the Postdoctoral Fellowship Program ofthe China postdoctoral Science Foundation(CPSF)(Grant GZC20233506)the China Postdoctoral Science Foundation(Grant2024M764252)the Natural Science Foundation of Chongqing China(2023NSCQ-MSX0097)Guangdong Basic and Applied Basic Research Foundation(2024A1515010918)Shenzhen Science and Technology Program(Grant JCYJ20240813150819026)the Fundamental Research Funds for the Central Universities。
文摘Lead-tin(Pb-Sn)perovskites with an ideal bandgap of 1.34-1.40 eV show great promise in perovskite solar cells(PSCs).Recently,to address the environmental pollution and Sn^(2+)oxidation problems of dimethyl sulfoxide,methylammonium acetate(MAAc)ionic liquid has been developed as an alternative to fabricate ideal bandgap MAPb_(0.7)Sn_(0.3)I_(3)(1.36 eV)film via hot-casting in air.However,the spontaneous crystallization of Pb-Sn perovskite initiated by heat-induced supersaturation is fast and random,setting critical challenges in regulating crystal growth during the film-forming process.Herein,a lattice activation strategy is developed to control the crystallization dynamics of MAPb_(0.7)Sn_(0.3)I_(3)in MAAc to produce films with micrometer-sized grains in air.FA is shown to activate the crystal lattice that facilitates the formation of intermediates and balances the crystal growth of MAPb_(0.7)Sn_(0.3)I_(3),producing films with a grain size of 2.78±0.17μm.Furthermore,4-fluoro-phenethylammonium and phenethylammonium are adopted to passivate the defects in the film and promote the energy level alignment at the top interface,respectively.The optimized PSC device achieved an efficiency of 18.24%with a short-circuit current of 29.84 mA/cm^(2),which are both the highest values in 1.36 eV Pb-Sn PSCs to date.Notably,the unencapsulated devices show excellent storage and air stability under various conditions.
基金support from the National Natural Science Foundation of China(41977233,U22A20601)Student Research Training Program of Fuzhou University(S202210386061).
文摘Fragmentation is a common phenomenon in the runout process of large rockslides.Rocks have different strengths under the influence of the rock type and weathering degree,resulting in varying fragmentation characteristics.However,the limited understanding of how rock strength influences the postfragmentation kinematic characteristics of rockslides is limited.Taking a natural rockslide as an example,this paper quantitatively analyzes the runout and deposition of the rockslide using the discrete element method(DEM)and examines the impacts of the rock strength on the runout and deposition characteristics of the rockslide.The results reveal that(1)Rock strength significantly influences fragmentation and runout characteristics:medium-to-high strength rocks exhibit two-stage fragmentation(10-20 s and 55-65 s),while weak-strength rocks achieve 98%fragmentation within 20 s.Optimal kinetic energy conversion occurs in medium-strength rocks,with a maximum velocity difference of 39.3 m/s between the anterior and posterior edges.(2)The sudden change in the cross-sectional dimensions of high-strength rocks under a high spreading velocity(>60 m/s)may amplify air blast hazards.(3)Deposition patterns reveal that the spatial distribution of fragments preserves original positional order;high-strength rocks produce larger fragments(nominal fragment size increases from 0.028 of weak-strength rocks to 0.607);and centroid displacement increases from 1907 m to 2117 m with rock strength in open terrains.(4)Energy dissipation analysis shows that frictional dissipation(>60%)>collisional dissipation(~37%)>>fragmentation dissipation(<2%)in the process of rockslide runout.The rock strength induces<5%variation in partitioning of energy dissipation.
基金supported by Capital health development research project(Grant No.2022-2G-4232)。
文摘Viruses, notably airborne viruses, are difficult to collect and detect because of the low concentrations of environmental microorganisms. Bacteriophages are frequently used in air experiments as suitable surrogates for human and animal viruses^([1]). Bacteriophages are non-pathogenic, so they are safe for laboratory workers and do not require specialized biological protection measures.Bacteriophages can be prepared at high titers using simple and low-cost methods.
基金a derivative product of the project INV-ING-3788 financed by the Vicerectory of Research of the Universidad Militar Nueva Granada,validity 2023.
文摘The use of additive manufacturing techniques in the development of unconventional materials can help reduce the environmental impact of traditional construction materials.In this paper,the properties of a 3D-printed biocomposite were evaluated.Biofilaments obtained by mixing pulverized bamboo fibers with polylactic acid(PLA)resin were extruded during the manufacturing process.To assess the effect of incorporating plant fibers,an analysis was conducted on the morphology,elemental chemical composition,crystallinity index,principal functional groups,thermal stability,surface roughness,microhardness,density,tensile strength,elastic modulus,and strain percentage of reinforced samples.The results were comparedwith those obtained from the characterization of standard PLAfilaments(unreinforced).The fused deposition modeling(FDM)technique was employed to print biocomposite specimens.Additionally,the influence of the printing parameters(infill density,build orientation,and layer thickness)on the physical,tribological,andmechanical properties of the biocomposites was analyzed.These results were compared with those obtained for specimens printed with pure PLA.The findings indicate that incorporating 10%vegetable filler into PLA filaments enhanced the strength and stiffness of the biocomposite under axial loads.Finally,the strength of the biocomposite subjected to axial loads was compared with the standardized values for wood-plastic composites,demonstrating the feasibility of its use for non-structural purposes in civil construction.
基金support of the Mount Taishan Industrial Leading Talent Project.
文摘Repairing the Ni-based superalloy component remains challenging due to the limited understanding of the role of the defect’s morphology on microstructure and related deformation responses.To address this issue,GH4099 Ni-based superalloy plate with U-shaped and V-shaped grooves was prepared and repaired by laser-directed energy deposition method using GH4099 powders.Both grooves exhibit three similar regions at the repaired interphase,which are the base metal region with equiaxed grains,repaired region with columnar or elongated equiaxed grains,and a transition region in between.High-temperature gradient in the repaired region induced a high density of substructures,and the repaired region in U-shaped grooves has an even higher temperature gradient due to fewer passes of the melted metal,which induces more metallic carbides in the subgrain boundaries and improves the tensile strength of the repaired samples.However,due to the steep side walls,local vortex might form at the bottom corner of the U-shaped groove,leaving macroscale holes and micro-cracks there.Such defects will decrease the alloy’s ductility.The relationship among groove morphology-macro-and microstructure-mechanical properties is then established,which suggesting the preferred V-shaped groove considering the flatter sidewall and more passes induced near equilibrium microstructure.
基金supported by the National Key Research and Development Plan Program of China(2022YFD2400600/2022YFD2400601/2022YFD2400603)the Science and Technology Innovation Program of Hunan Province(Grant No.2023RC1072)+1 种基金Scientific Research Fund of Hunan Provincial Education Department(Grant No.24B0799)the earmarked fund for HARS(HARS-07).
文摘Hardness is widely regarded as a critical factor influencing the whole texture of fish flesh.The objective of this study was to elucidate the regulatory mechanism underlying muscle hardness in hybrid bream(BBTB,Megalobrama amblycephala♀×Culter alburnus♂).A comparison of the physiological features of high hardness(HH)and low hardness(LH)muscle revealed that the former had higher contents of collagen I and lower muscle fiber diameter.Transcriptomic data revealed that the myofiber assembly pathway and the HIF-1 signaling pathway were activated in HH muscle.At the metabolic level,the categories of amino acids and lipids were the principal differentially abundant metabolites between the HH and LH muscle.The detection of amino acid profiles further revealed significant differences in amino acid metabolism between the HH and LH muscles,with the HH muscle having higher levels of amino acids than the LH muscle,especially hydroxypro-line(Hyp).Furthermore,through supplementation of Hyp in BBTB myoblasts,the results indicated that 0.8 mmol/L Hyp increased the proliferation,differentiation,migration,and collagen synthesis of myoblasts.Finally,BBTB was treated with Hyp intraperitoneally for 15 days.The results revealed that 0.1 g/kg Hyp significantly increased muscle hardness,myofiber density,myofibrillar protein synthesis,and HIF-1 protein content.The results obtained in this study indicated that Hyp supplementation promoted collagen synthesis and proliferation of myoblast and muscle fibers in the BBTB,which may be induced by activation of the transcription factor HIF1 and contributes to the impacts of Hyp on improvements in muscle hardness in the BBTB.
基金Project(2021YFC2801904) supported by the National Key R&D Program of ChinaProject(KY10100230067) supported by the Basic Product Innovation Research Project,China+3 种基金Projects(52271130,52305344) supported by the National Natural Science Foundation of ChinaProject(ZR2022QE073) supported by the Natural Science Foundation of Shandong Province,ChinaProject(AMGM2021F01) supported by the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai,ChinaProject(KY90200210015) supported by Leading Scientific Research Project of CNNC,China。
文摘In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition(LDED).The effects of ultrasonic vibration(UV)and tempering treatment on microstructure evolution,microhardness distribution and mechanical properties of deposition layer were studied in detail.The microstructure of UV assisted LDED sample after tempering is mainly composed of tempered sorbite(TS).Due to the improvement of microstructure inhomogeneity and grains refinement,UV assisted LDED sample with tempering treatment obtains excellent mechanical properties.The ultimate tensile strength(UTS),yield strength(YS)and elongation after breaking(EL)reach 765 MPa,657 MPa and 19.5%,the increase ratios of UTS and YS are 14.5%and 33.8%while maintaining plasticity compared to original LDED sample,respectively.It is obvious that ultrasonic vibration combined with tempering is a potential and effective method to obtain uniform microstructure and excellent mechanical properties in metal laser directed energy deposition field.
基金supported by the China Scholarship Council(No.202208210253)the Natural Science Foundation of Liaoning Province(2022-MS-272)the Scientific Research Funding Project of the Education Department of Liaoning Province(LJKMZ20220463).
文摘Al_(0.5)CrFeNi_(2.5)high-entropy alloy(HEA)was reinforced by the small-radius Si.Al_(0.5)CrFeNi_(2.5)Six(x=0 and 0.25)HEAs were fabricated by laser melting deposition.The evolution of microstructure,nanohardness,and wear properties of Al_(0.5)CrFeNi_(2.5)Six(x=0 and 0.25)HEAs were systematically investigated.Al_(0.5)CrFeNi_(2.5)HEA exhibits a face-centered cubic(FCC)matrix with Ni3Al-type ordered nanoprecipitates.When Si was doped,σphase and Cr-rich nanoprecipitates existed in the B2 matrix and L12 in the FCC matrix.The nanohardness was increased from 4.67 to 5.45 GPa with doping of Si,which is associated with forming the new phases and improved nanohardness of L12/FCC phases.The coefficient of friction(COF)value was reduced from 0.75 to 0.67 by adding Si.σphase and Cr-rich nanoprecipitates in B2 matrix support a decreased wear rate from 7.87×10^(-4) to 6.82×10^(-4) mm^(3)/(N m).Furthermore,the main wear mechanism of Al_(0.5)CrFeNi_(2.5)and Al_(0.5)CrFeNi_(2.5)Si0.25 HEAs is abrasive wear.
