Gallium nitride(GaN),as a third-generation semiconductor,is highly attractive due to its exceptional physical and chemical properties.Laser direct writing offers an efficient method for the precise processing of hard ...Gallium nitride(GaN),as a third-generation semiconductor,is highly attractive due to its exceptional physical and chemical properties.Laser direct writing offers an efficient method for the precise processing of hard and brittle materials.In this work,various types of surface microtexture were processed on GaN epilayers using a femtosecond laser with a wavelength of 1030 nm.The effects of the laser energy,singlepulse interval,number of pulses,and number of scan passes on groove machining were investigated with a view to achieving high-quality micromachining.The depth,width,surface morphology,and roughness of the grooves were analyzed using scanning electron microscopy,laser scanning confocal microscopy,and atomic force microscopy.Damage and stress were characterized at the microscale using Raman spectroscopy.High-quality precision machining of different types of periodic surface microtexture at 40 mW laser power was achieved by controlling the process parameters and laser trajectory.Finally,an initial exploration was conducted to examine vector-light-based microand nanostructure processing.The findings demonstrate the potential of femtosecond lasers for efficient micromachining of hard and brittle materials without the creation of heat-affected zones or microcracks.The high-quality textured structures achieved through this processing technique have broad and promising applications in optoelectronic devices and tribology.展开更多
The competition between dimensionality and ordering in multiferroic materials is of great interest for both fundamental physics and potential applications. Combining first-principles calculations with micromagnetic si...The competition between dimensionality and ordering in multiferroic materials is of great interest for both fundamental physics and potential applications. Combining first-principles calculations with micromagnetic simulations, we investigate recently synthesized ultrathin perovskite bismuth ferrite(BFO) films. Our numerical results reveal that, at the monolayer limit, the ferroelectricity of BFO is missing because the octahedral distortions are constrained. However, the monolayer bismuth ferrite is a topological antiferromagnetic metal with tunable bimeron magnetic structure. The dual topologically non-trivial characteristics make monolayer bismuth ferrite a multifunctional building block in future spintronic devices.展开更多
Texture and grain structure evolution during annealing and their effects on tensile strength and anisotropy were studied using XRD,DSC,SEM,EBSD and TEM.The results indicate that elevated rolling temperatures reduce th...Texture and grain structure evolution during annealing and their effects on tensile strength and anisotropy were studied using XRD,DSC,SEM,EBSD and TEM.The results indicate that elevated rolling temperatures reduce the f(g)_(max(Copper))/f(g)_(max(Brass))ratio,increase S-Brass fine bands,and promote S-dispersoid precipitation,leading to finer recrystallized grains.Dominant recrystallization textures transform from Goss+P to Goss and then to Goss+Cube with increasing rolling temperature.Annealing at 350℃shows four tensile strength response stages:fast softening I,rapid strengthening II,slow strengthening III,and slow softening IV.The transition from Stages I to II is driven by the formation of strong Goss and P textures,and Stage IV is linked to enhanced Cube texture.Plates with Goss+Cube textures and fine equiaxed grains exhibit the lowest YS/UTS ratio and minimal anisotropy.展开更多
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun...[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua.展开更多
The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Sur...The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level."展开更多
The performance of hematite(α-Fe_(2)O_(3))photoanodes for photoelectrochemical(PEC)water splitting has been limited to around 2-5 mA cm^(-2)under standard conditions due to their short hole diffusion length and slugg...The performance of hematite(α-Fe_(2)O_(3))photoanodes for photoelectrochemical(PEC)water splitting has been limited to around 2-5 mA cm^(-2)under standard conditions due to their short hole diffusion length and sluggish oxygen evolution reaction kinetics.This work overcomes those challenges through a synergistic strategy that co-designs the hematite architecture and the surface reaction pathway.We introduce a textured and hierarchically porous Ti-doped Fe_(2)O_(3)(tp-Fe_(2)O_(3))photoanode,synthesized via multi-cycle growth and flame annealing method.This unique architecture features a high texture(110),enlarged surface area,and hierarchically porous structure,which enable significantly enhanced bulk charge transport and interfacial charge transfer compared to typical nanorod Ti-doped Fe_(2)O_(3)(nr-Fe_(2)O_(3)).As a result,the tp-Fe_(2)O_(3)photoanode achieves a photocurrent density of 3.1 mA cm^(-2)at 1.23 V vs.RHE with exceptional stability over 105 h,notably without any co-catalyst.By replacing the OER with the hydrazine oxidation reaction,the photocurrent further reaches a record-high level of 7.1 mA cm^(-2)at 1.23 V_(RHE).Finally,when we integrate the tp-Fe_(2)O_(3)with a commercial Si solar cell,it achieves a solar-to-hydrogen efficiency of 8.7%-the highest reported value for any Fe_(2)O_(3)-based PVtandem system.This work provides critical insights into rational Fe_(2)O_(3)photoanode design and highlights the potential of hydrazine as an efficient alternative anodic reaction,enabling waste valorization.展开更多
The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly fa...The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly faces two challenges:one is the loss of information and interference caused by occlusion and stacking in the sorting scenario,the other is the difficulty of feature extraction due to the weak texture of industrial parts.To address the above problems,this paper proposes an attention-based pixel-level voting network for 6D pose estimation of weakly textured industrial parts,namely CB-PVNet.On the one hand,the voting scheme can predict the keypoints of affected pixels,which improves the accuracy of keypoint localization even in scenarios such as weak texture and partial occlusion.On the other hand,the attention mechanism can extract interesting features of the object while suppressing useless features of surroundings.Extensive comparative experiments were conducted on both public datasets(including LINEMOD,Occlusion LINEMOD and T-LESS datasets)and self-made datasets.The experimental results indicate that the proposed network CB-PVNet can achieve accuracy of ADD(-s)comparable to state-of-the-art using only RGB images while ensuring real-time performance.Additionally,we also conducted robot grasping experiments in the real world.The balance between accuracy and computational efficiency makes the method well-suited for applications in industrial automation.展开更多
Aqueous zinc-ion batteries(AZIBs)are currently confronted with the challenge of achieving long-term cyclic stability under high current densities.This issue is primarily attributed to the excessive growth of dendrites...Aqueous zinc-ion batteries(AZIBs)are currently confronted with the challenge of achieving long-term cyclic stability under high current densities.This issue is primarily attributed to the excessive growth of dendrites and the occurrence of significant side reactions.Herein,sucralose(SCL),as an electrolyte additive,has been used to promote the exposure of the Zn(002)texture.The introduction of SCL can adjust the Zn~(2+)nucleation and diffusion along different crystal facets,promoting the exposure of the Zn(002)texture.By substituting water molecules in the[Zn(H_(2)O)_(6)]~(2+),SCL reconfigures the hydrogen bond network in the electrolyte,reconstructing the solvation structure and suppressing the hydrogen evolution reaction.Consequently,the Zn//Zn symmetric battery exhibits long-term cycling stability of over 4900 h at 1 mA cm^(-2)-1 mAh cm^(-2).Even at a harsh condition of 30 mA cm^(-2)-30 mAh cm^(-2)(DOD=73.3%),it can stably cycle for 171 h.The CE of the Zn//Cu half battery reaches 99.61% at 0.2 mA cm^(-2)with 0.2 mAh cm^(-2).Employing the optimized electrolyte,after 500 cycles,a high specific capacity of 420 mAh g^(-1)can be retained for the NH_4V_4O_(10)//Zn full battery at 500 mA g^(-1),corresponding to a capacity retention of 90.7%.展开更多
Phosphorus(P)leaching in alkaline soils,exacerbated by excessive fertilizer application,represents a significant pathway for P loss.While soil pore structure and texture critically regulate P transport,mechanisms gove...Phosphorus(P)leaching in alkaline soils,exacerbated by excessive fertilizer application,represents a significant pathway for P loss.While soil pore structure and texture critically regulate P transport,mechanisms governing P loss in texturally diverse alkaline soils remain unclear.This study investigated P leaching dynamics and transport parameters across four alkaline soil textures(silty clay,clay loam,loam,sandy loam)using a one-dimensional convective-diffusion equation(CDE)based on column experiments.Results indicated that phosphorus leaching kinetics were predominantly governed by diffusion transport,evidenced by low Peclet numbers(P_(e))(ranged from 0.02 to 0.31)across varying textures and initial P concentrations(C_(0)).Comparative analysis of transport parameters revealed significant textural effects on dispersion coefficient(D),retardation factor(R),pore water velocity(V),P_(e),and diffusion coefficient(λ)(F>523.42,p<0.001).Among these,only D,P_(e) andλexhibited substantial differences in response to variations in C_(0)(F>89.47,p<0.001).Saturated hydraulic conductivity(K_(s))(R^(2)=62.9%,p<0.01)and total pore area(A)(R^(2)=12.4%,p<0.01)emerged as primary regulators of P leaching.Enhanced clay content increased total pore area while reducing average pore diameter,concurrently decreasing pore water velocity and saturated infiltration rates.These textural modifications amplified diffusive P transport within soil matrices.The findings provide mechanistic insights into texturedependent P mobility in alkaline environments,informing targeted strategies for agricultural phosphorus management.展开更多
To investigate the evolution of grain orientation and slip modes in magnesium alloys with multiple texture components,an AZ31 gradient-structured magnesium alloy sheet was fabricated using hard plate rolling(HPR).The ...To investigate the evolution of grain orientation and slip modes in magnesium alloys with multiple texture components,an AZ31 gradient-structured magnesium alloy sheet was fabricated using hard plate rolling(HPR).The changes in texture and slip modes under different reductions were examined.The results demonstrate that the AZ31 magnesium alloy sheets display a self-epitaxial gradient structure,with the best mechanical properties observed at rolling temperature of 673 K and reduction of 50%.Significant changes in texture type and strength are observed along the normal direction(ND)of the sheet.The coarse-grain region exhibits a bimodal texture aligned with the rolling direction.These texture variations enhance the stress distribution at the fine grain-coarse grain interface,influencing the grain orientation and the activation of different slip modes,thus improving the mechanical properties of gradient-structured magnesium alloy sheets.This approach offers a new strategy for the fabrication of high-performance magnesium alloy sheets.展开更多
Floating ring bearings are widely used in high-speed turbomachinery such as turbochargers and turbogenerators.Research-ers have recently explored various surface texturing strategies on the inner surface of floating r...Floating ring bearings are widely used in high-speed turbomachinery such as turbochargers and turbogenerators.Research-ers have recently explored various surface texturing strategies on the inner surface of floating rings to enhance bearing performance.In this study,the herring patterns are textured on the inner surface of the floating ring.This pattern is inspired by the secondary flight feathers of the Indian pigeon,which aid the bird in reducing viscous drag during flight.The result-ing Herringbone Textured Floating Ring Bearing(HTFRB)is investigated for its potential application in locomotive turbo-chargers.The HTFRB is numerically modeled using the Reynolds equation to evaluate the bearing's pressure distribution and static characteristics,including load-carrying capacity,power loss,and side leakage.Dynamic characteristics are determined by solving the zeroth-and first-order perturbed Reynolds equation.A Sobol sensitivity analysis is conducted to quantify the influence of groove parameters-helix angle,groove depth,groove width ratio,and number of grooves-on bearing performance metrics.An artificial intelligence-based optimization framework,integrating artificial neural networks and adaptive neuro-fuzzy inference systems,is developed to maximize load carrying capacity while minimiz-ing power loss,side leakage,and friction coefficient.The optimized texture parameters obtained from this framework are employed to validate the ANN model and evaluate the static and dynamic characteristics of the HTFRB.The dynamic coefficients of the HTFRB are further employed to evaluate the stability and robustness of the turbocharger rotor-HTFRB system.This study underscores the potential of combining bio-inspired texture design with numerical modeling and AI-based optimization to develop high-performance HTFRB.展开更多
The recrystallization textures in 95%rolled aluminum sheets with different purities and initial textures were investigated.The effects of recovery levels and the dragging effects induced by impurities on the effective...The recrystallization textures in 95%rolled aluminum sheets with different purities and initial textures were investigated.The effects of recovery levels and the dragging effects induced by impurities on the effective driving force and corresponding behaviors of oriented nucleation and oriented growth during annealing were analyzed.The oriented nucleation is a common behavior in the initial stage of primary recrystallization if the effective driving force in deformed matrix is not too high to reduce the necessity of nucleation period.Oriented growth might appear if the temperature is not too high and the grains,of which the misorientation to matrix is about 40°〈111〉,have enough time and space to expand growth advantages,while certain reduction of effective driving force is also necessary.The recrystallization textures could be changed by controlling initial textures and effective driving forces which can be regulated by recovery levels and dragging effects.展开更多
The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction（EBSD） analyses. A weak recrystallizati...The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction（EBSD） analyses. A weak recrystallization texture was observed in the AA 3003 alloy annealed at 783 K due to the high annealing temperature. Under the same conditions, extremely high P {011 } （ 111 ） recrystallization textures were detected in the AA 3003 alloy added with 0. 39% Sc. Based on the EBSD results, no intensely preferential orientation nucleation of recrystallization grains was observed in the early stage of recrystallizafion for both alloys. However, concurrent precipitation strongly retarded the growth of recrystallization grains, except for P nucleation sites, thereby conferring an apparent initial growth advantage for P nucleation sites compared with other nucleation sites. Therefore, a sharp P {011 } 〈 111 〉 texture appeared in concurrently precipitated AA 3003 alloys.展开更多
The deformation and recrystallization textures of 6111 Al alloy with various precipitation states have been investigated by means of the orientation distribution functions (ODFs). It was found that the precipitation s...The deformation and recrystallization textures of 6111 Al alloy with various precipitation states have been investigated by means of the orientation distribution functions (ODFs). It was found that the precipitation state had significant effects on both rolling and recrystallization textures of Al alloy. For the alloy with no or little precipitate, the orientation intensities were distributed more homogeneously along the β-fiber. With increasing aging temperature, the orientation intensities along the β-fiber increased firstly and decreased then. Simultaneity, the orientation intensities along the β-fiber were distributed more and more inhomogeneously. On the other hand, with the precipitates increasing the recrystallization textures changed gradually from {001}<UVW> and very weak {011}<111> orientation to the strong {001}<311> and {011}<111> orientation.展开更多
The microstructure, texture characteristics and torsion ability of two kinds of steel wires were investigated. The eutectoid steel wires were produced by hot and cold drawing with severe deformation. The torsinability...The microstructure, texture characteristics and torsion ability of two kinds of steel wires were investigated. The eutectoid steel wires were produced by hot and cold drawing with severe deformation. The torsinability of steel wires was measured under two cases, i.e. there exists either fiber texture or circular texture. The results showed that the torsional behavior of the steel wires was affected by their textures and microstructures. The {110}<110> circular texture weakened the torsion ability of the wires. The torsion fracture behavior of {110}<110> texture wires is related to the fact that only two slip systems were activated under simple shear strain deformation.展开更多
In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamo...In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamorphic reactions. In addition to garnet, jadeititic-clinopyroxene and rutile, other peak stage (M2) minerals in some gneisses include phengite, aragonite and coesite or quartz pseudomorphs after coesite. The typical peak-stage mineral assemblages in gneisses are characterized by garnet + jadeitic-clinopyroxene + rutile + coesite, garnet + jadeitic-clinopyroxene + phengite + rutile ± coesite and garnet + jadeitic-clinopyroxene + aragonite + rutile ± coesite. The grossular content (Gro) in garnet is high and may reach 50. 1 mol%. The SiO2 content of phengite ranges from 54.37% to 54.84% with 3.54-3.57 p.f.u. Quartz pseudomorphs after coesite occur as inclusions in garnet.The gneisses of the Donghai area have been subjected to multistage recrystallization and exhibit a closewise P-T evolutional path characterized by the near-isothermal decompression. The inclusion assemblage (Hb+Ep+Bi+Pl+Qz) within garnet and other minerals has recorded a pre-peak stage (Mi) epidote amphibole fades metamorphic event. High- and ultrahigh-pressure peak metamorphism (M2) took place at T=750-860℃ and P>2.7 GPa. The symplectitic assemblages after garnet, jadeitic-clinopyroxene and rutile imply a near-isothermal decompression metamorphism (M3, M4) during the rapid exhumation. Several lines of evidence of petrography and metamorphic reactions indicate that both gneisses and eclogites have experienced ultrahigh-pressure metamorphism in the Donghai area. This research may be of great significance for an in-depth study of the metamorphism and tectonic evolution in the Su-Lu ultrahigh-pressure metamorphic belt.展开更多
The texture evolution in a high strength Ti-IF steel during the processing of hot rolling, cold rolling, and annealing is studied. For comparison, both ferrite rolling and austenite rolling are employed. It is found t...The texture evolution in a high strength Ti-IF steel during the processing of hot rolling, cold rolling, and annealing is studied. For comparison, both ferrite rolling and austenite rolling are employed. It is found that the texture type is the. same after ferrite rolling and austenite rolling, but the texture intensity is much higher in the ferrite rolled sample. Furthermore, texture characteristics at the surface are absolutely different from those at the mid sec tion in both ferrite rolled and austenite rolled samples, as well as under the cold rolled and annealed conditions. The shear texture { 110 } 〈001 〉 disappears and orientation rotates along { 110 } 〈001 〉→ { 554 } 〈 225 〉→ { 111 } 〈 112 〉→{111}〈110〉→{223}〈110〉 during cold rolling. Compared to the austenite rolled sample, the properties of the cold rolled and annealed sheet which is subjected to ferrite rolling are higher.展开更多
Channel die compression and initial textures are used to activate different deformation mechanisms in a fine-grained magnesium alloy AZ31. The σ-ε curves, microstructures and, particularly, textures are analyzed to ...Channel die compression and initial textures are used to activate different deformation mechanisms in a fine-grained magnesium alloy AZ31. The σ-ε curves, microstructures and, particularly, textures are analyzed to reveal different deformation mechanisms and to compare with those of coarse grained samples. Dominant double-prismatic slip, {1012} twinning and basal slip are detected in three types of samples, respectively, which is similar to those of coarse grained samples. The detrimental effect of shear band formation or {1011} twinning is limited in fine grained microstructure. In addition to the higher flow stress at low temperature an early decrease in flow stress at higher temperature is also found in fine-grained samples in comparison with their coarse-grained counterparts. This softening is ascribed to the early dynamic recrystallization or grain boundary glide.展开更多
Texture evolution in nickel, copper and α-brass that are representative of face-centered-cubic （fcc） materials with different stacking fault energy （SFE） during cold rolling was systematically investigated. X-ray...Texture evolution in nickel, copper and α-brass that are representative of face-centered-cubic （fcc） materials with different stacking fault energy （SFE） during cold rolling was systematically investigated. X-ray diffraction, scanning electron microscopy and electron backscatter diffraction techniques were employed to characterize microstructures and local orientation distributions of specimens at different thickness reductions. Besides, Taylor and Schmid factors of the {111} 〈110〉 slip systems and {111} 〈112〉 twin systems for some typical orientations were utilized to explore the relationship between texture evolution and deformation microstructures. It was found that in fcc metals with low SFE at large deformations, the copper-oriented grains rotated around the 〈110〉 crystallographic axis through the brass-R orientation to the Goss orientation, and finally toward the brass orientation. The initiation of shear banding was the dominant mechanism for the above-mentioned texture transition.展开更多
Study of dolomite texture can contribute to understanding the process of dolomitization.This research reports textures and homogenization temperatures of dolomites from the Permian-Triassic strata in the Sichuan Basin...Study of dolomite texture can contribute to understanding the process of dolomitization.This research reports textures and homogenization temperatures of dolomites from the Permian-Triassic strata in the Sichuan Basin and the Lower Paleozoic strata in the Tarim Basin,which provided insights into relationships between dolomite textures and their formation temperatures.Our results are summarized as follows：1） dolomites with well-preserved texture indicate low dolomitization temperature.However,in certain diagenetic environments,the hydrothermal dolomitization may completely or partially preserve the original texture of dolomites.2） The formation temperatures of non-planar dolomites are always higher than those of planar dolomites.3） The formation temperatures of dolomite cements are generally higher than those of replacive dolomites.4） Although the formation temperatures of saddle dolomite cements have a wide range,they show higher values than those of the planar subhedral to euhedral dolomite cements.Thus,saddle dolomites could generally be an indicator of high precipitation temperature.5） The fluid Mg/Ca ratio is another element controlling dolomite morphology.Micritic dolomites,which precipitate from hypersaline fluids with a high Mg/Ca ratio in a subaerial environment could also have features of non-planar anhedral crystal shape because of rapid nucleation and crystallization during dolomitization.展开更多
基金supported by the Henan Key Laboratory of Intelligent Manufacturing Equipment Integration for Superhard Materials(Grant No.JDKJ2022-01)the National Natural Science Foundation of China(Grant Nos.52035009 and 51761135106)+1 种基金the 2020 Mobility Programme of the Sino-German Center for Research Promotion(Grant No.M-0396)the“111”project by the State Administration of Foreign Experts Affairs and the Ministry of Education of China(Grant No.B07014).
文摘Gallium nitride(GaN),as a third-generation semiconductor,is highly attractive due to its exceptional physical and chemical properties.Laser direct writing offers an efficient method for the precise processing of hard and brittle materials.In this work,various types of surface microtexture were processed on GaN epilayers using a femtosecond laser with a wavelength of 1030 nm.The effects of the laser energy,singlepulse interval,number of pulses,and number of scan passes on groove machining were investigated with a view to achieving high-quality micromachining.The depth,width,surface morphology,and roughness of the grooves were analyzed using scanning electron microscopy,laser scanning confocal microscopy,and atomic force microscopy.Damage and stress were characterized at the microscale using Raman spectroscopy.High-quality precision machining of different types of periodic surface microtexture at 40 mW laser power was achieved by controlling the process parameters and laser trajectory.Finally,an initial exploration was conducted to examine vector-light-based microand nanostructure processing.The findings demonstrate the potential of femtosecond lasers for efficient micromachining of hard and brittle materials without the creation of heat-affected zones or microcracks.The high-quality textured structures achieved through this processing technique have broad and promising applications in optoelectronic devices and tribology.
基金supported by the National Natural Science Foundation of China (Grant No. 12174382)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant Nos. XDB0460000 and XDB28000000)the Innovation Program for Quantum Science and Technology (Grant Nos. 2024ZD0300104 and 2021ZD0302600)。
文摘The competition between dimensionality and ordering in multiferroic materials is of great interest for both fundamental physics and potential applications. Combining first-principles calculations with micromagnetic simulations, we investigate recently synthesized ultrathin perovskite bismuth ferrite(BFO) films. Our numerical results reveal that, at the monolayer limit, the ferroelectricity of BFO is missing because the octahedral distortions are constrained. However, the monolayer bismuth ferrite is a topological antiferromagnetic metal with tunable bimeron magnetic structure. The dual topologically non-trivial characteristics make monolayer bismuth ferrite a multifunctional building block in future spintronic devices.
基金financial support from the National Key Research and Development Program of China(No.2016YFB0300900)the National Key Fundamental Research Project of China(No.2012CB619506-3)the National Natural Science Foundation of China(No.51171209)。
文摘Texture and grain structure evolution during annealing and their effects on tensile strength and anisotropy were studied using XRD,DSC,SEM,EBSD and TEM.The results indicate that elevated rolling temperatures reduce the f(g)_(max(Copper))/f(g)_(max(Brass))ratio,increase S-Brass fine bands,and promote S-dispersoid precipitation,leading to finer recrystallized grains.Dominant recrystallization textures transform from Goss+P to Goss and then to Goss+Cube with increasing rolling temperature.Annealing at 350℃shows four tensile strength response stages:fast softening I,rapid strengthening II,slow strengthening III,and slow softening IV.The transition from Stages I to II is driven by the formation of strong Goss and P textures,and Stage IV is linked to enhanced Cube texture.Plates with Goss+Cube textures and fine equiaxed grains exhibit the lowest YS/UTS ratio and minimal anisotropy.
基金Supported by Shanghai Agriculture Applied Technology Development Program (Grant No.T20220120).
文摘[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua.
文摘The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level."
基金supported by a National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.RS-2024-00335976)。
文摘The performance of hematite(α-Fe_(2)O_(3))photoanodes for photoelectrochemical(PEC)water splitting has been limited to around 2-5 mA cm^(-2)under standard conditions due to their short hole diffusion length and sluggish oxygen evolution reaction kinetics.This work overcomes those challenges through a synergistic strategy that co-designs the hematite architecture and the surface reaction pathway.We introduce a textured and hierarchically porous Ti-doped Fe_(2)O_(3)(tp-Fe_(2)O_(3))photoanode,synthesized via multi-cycle growth and flame annealing method.This unique architecture features a high texture(110),enlarged surface area,and hierarchically porous structure,which enable significantly enhanced bulk charge transport and interfacial charge transfer compared to typical nanorod Ti-doped Fe_(2)O_(3)(nr-Fe_(2)O_(3)).As a result,the tp-Fe_(2)O_(3)photoanode achieves a photocurrent density of 3.1 mA cm^(-2)at 1.23 V vs.RHE with exceptional stability over 105 h,notably without any co-catalyst.By replacing the OER with the hydrazine oxidation reaction,the photocurrent further reaches a record-high level of 7.1 mA cm^(-2)at 1.23 V_(RHE).Finally,when we integrate the tp-Fe_(2)O_(3)with a commercial Si solar cell,it achieves a solar-to-hydrogen efficiency of 8.7%-the highest reported value for any Fe_(2)O_(3)-based PVtandem system.This work provides critical insights into rational Fe_(2)O_(3)photoanode design and highlights the potential of hydrazine as an efficient alternative anodic reaction,enabling waste valorization.
基金supported by the Knowledge Innovation Program of Wuhan-Shuguang Project(Grant No.2023010201020443)the School-Level Scientific Research Project Funding Program of Jianghan University(Grant No.2022XKZX33)the Natural Science Foundation of Hubei Province(Grant No.2024AFB466).
文摘The 6D pose estimation of objects is of great significance for the intelligent assembly and sorting of industrial parts.In the industrial robot production scenarios,the 6D pose estimation of industrial parts mainly faces two challenges:one is the loss of information and interference caused by occlusion and stacking in the sorting scenario,the other is the difficulty of feature extraction due to the weak texture of industrial parts.To address the above problems,this paper proposes an attention-based pixel-level voting network for 6D pose estimation of weakly textured industrial parts,namely CB-PVNet.On the one hand,the voting scheme can predict the keypoints of affected pixels,which improves the accuracy of keypoint localization even in scenarios such as weak texture and partial occlusion.On the other hand,the attention mechanism can extract interesting features of the object while suppressing useless features of surroundings.Extensive comparative experiments were conducted on both public datasets(including LINEMOD,Occlusion LINEMOD and T-LESS datasets)and self-made datasets.The experimental results indicate that the proposed network CB-PVNet can achieve accuracy of ADD(-s)comparable to state-of-the-art using only RGB images while ensuring real-time performance.Additionally,we also conducted robot grasping experiments in the real world.The balance between accuracy and computational efficiency makes the method well-suited for applications in industrial automation.
基金supported by the Anhui Provincial Science and Technology Innovation Initiative(202423i08050051)the Anhui Provincial Natural Science Foundation(2408085MB029)+1 种基金the HFIPS Director’s Fund(YZJJGGZX202201)the Natural Science Foundation of Hebei Province of China(B2024402018)。
文摘Aqueous zinc-ion batteries(AZIBs)are currently confronted with the challenge of achieving long-term cyclic stability under high current densities.This issue is primarily attributed to the excessive growth of dendrites and the occurrence of significant side reactions.Herein,sucralose(SCL),as an electrolyte additive,has been used to promote the exposure of the Zn(002)texture.The introduction of SCL can adjust the Zn~(2+)nucleation and diffusion along different crystal facets,promoting the exposure of the Zn(002)texture.By substituting water molecules in the[Zn(H_(2)O)_(6)]~(2+),SCL reconfigures the hydrogen bond network in the electrolyte,reconstructing the solvation structure and suppressing the hydrogen evolution reaction.Consequently,the Zn//Zn symmetric battery exhibits long-term cycling stability of over 4900 h at 1 mA cm^(-2)-1 mAh cm^(-2).Even at a harsh condition of 30 mA cm^(-2)-30 mAh cm^(-2)(DOD=73.3%),it can stably cycle for 171 h.The CE of the Zn//Cu half battery reaches 99.61% at 0.2 mA cm^(-2)with 0.2 mAh cm^(-2).Employing the optimized electrolyte,after 500 cycles,a high specific capacity of 420 mAh g^(-1)can be retained for the NH_4V_4O_(10)//Zn full battery at 500 mA g^(-1),corresponding to a capacity retention of 90.7%.
基金supported by the National Natural Science Foundation of China(Nos.42077067,42277329)the Projects of Talents Recruitment of GDUPT(No.XJ2005000301)。
文摘Phosphorus(P)leaching in alkaline soils,exacerbated by excessive fertilizer application,represents a significant pathway for P loss.While soil pore structure and texture critically regulate P transport,mechanisms governing P loss in texturally diverse alkaline soils remain unclear.This study investigated P leaching dynamics and transport parameters across four alkaline soil textures(silty clay,clay loam,loam,sandy loam)using a one-dimensional convective-diffusion equation(CDE)based on column experiments.Results indicated that phosphorus leaching kinetics were predominantly governed by diffusion transport,evidenced by low Peclet numbers(P_(e))(ranged from 0.02 to 0.31)across varying textures and initial P concentrations(C_(0)).Comparative analysis of transport parameters revealed significant textural effects on dispersion coefficient(D),retardation factor(R),pore water velocity(V),P_(e),and diffusion coefficient(λ)(F>523.42,p<0.001).Among these,only D,P_(e) andλexhibited substantial differences in response to variations in C_(0)(F>89.47,p<0.001).Saturated hydraulic conductivity(K_(s))(R^(2)=62.9%,p<0.01)and total pore area(A)(R^(2)=12.4%,p<0.01)emerged as primary regulators of P leaching.Enhanced clay content increased total pore area while reducing average pore diameter,concurrently decreasing pore water velocity and saturated infiltration rates.These textural modifications amplified diffusive P transport within soil matrices.The findings provide mechanistic insights into texturedependent P mobility in alkaline environments,informing targeted strategies for agricultural phosphorus management.
基金supported by the Natural Science Foundation of Heilongjiang Province,China(No.JQ2022E004)。
文摘To investigate the evolution of grain orientation and slip modes in magnesium alloys with multiple texture components,an AZ31 gradient-structured magnesium alloy sheet was fabricated using hard plate rolling(HPR).The changes in texture and slip modes under different reductions were examined.The results demonstrate that the AZ31 magnesium alloy sheets display a self-epitaxial gradient structure,with the best mechanical properties observed at rolling temperature of 673 K and reduction of 50%.Significant changes in texture type and strength are observed along the normal direction(ND)of the sheet.The coarse-grain region exhibits a bimodal texture aligned with the rolling direction.These texture variations enhance the stress distribution at the fine grain-coarse grain interface,influencing the grain orientation and the activation of different slip modes,thus improving the mechanical properties of gradient-structured magnesium alloy sheets.This approach offers a new strategy for the fabrication of high-performance magnesium alloy sheets.
文摘Floating ring bearings are widely used in high-speed turbomachinery such as turbochargers and turbogenerators.Research-ers have recently explored various surface texturing strategies on the inner surface of floating rings to enhance bearing performance.In this study,the herring patterns are textured on the inner surface of the floating ring.This pattern is inspired by the secondary flight feathers of the Indian pigeon,which aid the bird in reducing viscous drag during flight.The result-ing Herringbone Textured Floating Ring Bearing(HTFRB)is investigated for its potential application in locomotive turbo-chargers.The HTFRB is numerically modeled using the Reynolds equation to evaluate the bearing's pressure distribution and static characteristics,including load-carrying capacity,power loss,and side leakage.Dynamic characteristics are determined by solving the zeroth-and first-order perturbed Reynolds equation.A Sobol sensitivity analysis is conducted to quantify the influence of groove parameters-helix angle,groove depth,groove width ratio,and number of grooves-on bearing performance metrics.An artificial intelligence-based optimization framework,integrating artificial neural networks and adaptive neuro-fuzzy inference systems,is developed to maximize load carrying capacity while minimiz-ing power loss,side leakage,and friction coefficient.The optimized texture parameters obtained from this framework are employed to validate the ANN model and evaluate the static and dynamic characteristics of the HTFRB.The dynamic coefficients of the HTFRB are further employed to evaluate the stability and robustness of the turbocharger rotor-HTFRB system.This study underscores the potential of combining bio-inspired texture design with numerical modeling and AI-based optimization to develop high-performance HTFRB.
文摘The recrystallization textures in 95%rolled aluminum sheets with different purities and initial textures were investigated.The effects of recovery levels and the dragging effects induced by impurities on the effective driving force and corresponding behaviors of oriented nucleation and oriented growth during annealing were analyzed.The oriented nucleation is a common behavior in the initial stage of primary recrystallization if the effective driving force in deformed matrix is not too high to reduce the necessity of nucleation period.Oriented growth might appear if the temperature is not too high and the grains,of which the misorientation to matrix is about 40°〈111〉,have enough time and space to expand growth advantages,while certain reduction of effective driving force is also necessary.The recrystallization textures could be changed by controlling initial textures and effective driving forces which can be regulated by recovery levels and dragging effects.
基金The National Natural Science Foundation of China(No.51201031)the Natural Science Foundation of Jiangsu Province(No.BK2011615)the Transformation Program of Science and Technology Achievements of Jiangsu Province(No.BA2011024)
文摘The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction（EBSD） analyses. A weak recrystallization texture was observed in the AA 3003 alloy annealed at 783 K due to the high annealing temperature. Under the same conditions, extremely high P {011 } （ 111 ） recrystallization textures were detected in the AA 3003 alloy added with 0. 39% Sc. Based on the EBSD results, no intensely preferential orientation nucleation of recrystallization grains was observed in the early stage of recrystallizafion for both alloys. However, concurrent precipitation strongly retarded the growth of recrystallization grains, except for P nucleation sites, thereby conferring an apparent initial growth advantage for P nucleation sites compared with other nucleation sites. Therefore, a sharp P {011 } 〈 111 〉 texture appeared in concurrently precipitated AA 3003 alloys.
文摘The deformation and recrystallization textures of 6111 Al alloy with various precipitation states have been investigated by means of the orientation distribution functions (ODFs). It was found that the precipitation state had significant effects on both rolling and recrystallization textures of Al alloy. For the alloy with no or little precipitate, the orientation intensities were distributed more homogeneously along the β-fiber. With increasing aging temperature, the orientation intensities along the β-fiber increased firstly and decreased then. Simultaneity, the orientation intensities along the β-fiber were distributed more and more inhomogeneously. On the other hand, with the precipitates increasing the recrystallization textures changed gradually from {001}<UVW> and very weak {011}<111> orientation to the strong {001}<311> and {011}<111> orientation.
基金This work is supported by key project of the National Nat-ural Science Foundation of China(Grant No.50231030)the National High Technology Research and Development Pro-gram of China(Grant No.2003AA331030)the Teaching and Research Award Program for Outstanding Young Teach-ers in Higher Education Institutions.
文摘The microstructure, texture characteristics and torsion ability of two kinds of steel wires were investigated. The eutectoid steel wires were produced by hot and cold drawing with severe deformation. The torsinability of steel wires was measured under two cases, i.e. there exists either fiber texture or circular texture. The results showed that the torsional behavior of the steel wires was affected by their textures and microstructures. The {110}<110> circular texture weakened the torsion ability of the wires. The torsion fracture behavior of {110}<110> texture wires is related to the fact that only two slip systems were activated under simple shear strain deformation.
文摘In the gneisses from the drillhole ZK2304 of the Donghai area, there have been preserved high- and ultrahigh-pressure metamorphic mineral assemblages, a series of complicated retrogressive textures and relevant metamorphic reactions. In addition to garnet, jadeititic-clinopyroxene and rutile, other peak stage (M2) minerals in some gneisses include phengite, aragonite and coesite or quartz pseudomorphs after coesite. The typical peak-stage mineral assemblages in gneisses are characterized by garnet + jadeitic-clinopyroxene + rutile + coesite, garnet + jadeitic-clinopyroxene + phengite + rutile ± coesite and garnet + jadeitic-clinopyroxene + aragonite + rutile ± coesite. The grossular content (Gro) in garnet is high and may reach 50. 1 mol%. The SiO2 content of phengite ranges from 54.37% to 54.84% with 3.54-3.57 p.f.u. Quartz pseudomorphs after coesite occur as inclusions in garnet.The gneisses of the Donghai area have been subjected to multistage recrystallization and exhibit a closewise P-T evolutional path characterized by the near-isothermal decompression. The inclusion assemblage (Hb+Ep+Bi+Pl+Qz) within garnet and other minerals has recorded a pre-peak stage (Mi) epidote amphibole fades metamorphic event. High- and ultrahigh-pressure peak metamorphism (M2) took place at T=750-860℃ and P>2.7 GPa. The symplectitic assemblages after garnet, jadeitic-clinopyroxene and rutile imply a near-isothermal decompression metamorphism (M3, M4) during the rapid exhumation. Several lines of evidence of petrography and metamorphic reactions indicate that both gneisses and eclogites have experienced ultrahigh-pressure metamorphism in the Donghai area. This research may be of great significance for an in-depth study of the metamorphism and tectonic evolution in the Su-Lu ultrahigh-pressure metamorphic belt.
基金National Natural Science Foundation of China (50104004)
文摘The texture evolution in a high strength Ti-IF steel during the processing of hot rolling, cold rolling, and annealing is studied. For comparison, both ferrite rolling and austenite rolling are employed. It is found that the texture type is the. same after ferrite rolling and austenite rolling, but the texture intensity is much higher in the ferrite rolled sample. Furthermore, texture characteristics at the surface are absolutely different from those at the mid sec tion in both ferrite rolled and austenite rolled samples, as well as under the cold rolled and annealed conditions. The shear texture { 110 } 〈001 〉 disappears and orientation rotates along { 110 } 〈001 〉→ { 554 } 〈 225 〉→ { 111 } 〈 112 〉→{111}〈110〉→{223}〈110〉 during cold rolling. Compared to the austenite rolled sample, the properties of the cold rolled and annealed sheet which is subjected to ferrite rolling are higher.
基金This work was supported by the National Natural Sci-ence Foundation of China under grant No.50171009the National 863 Program of China(No.2002A A305501)Part work was performed at IMM RWTH A achen,Germany.
文摘Channel die compression and initial textures are used to activate different deformation mechanisms in a fine-grained magnesium alloy AZ31. The σ-ε curves, microstructures and, particularly, textures are analyzed to reveal different deformation mechanisms and to compare with those of coarse grained samples. Dominant double-prismatic slip, {1012} twinning and basal slip are detected in three types of samples, respectively, which is similar to those of coarse grained samples. The detrimental effect of shear band formation or {1011} twinning is limited in fine grained microstructure. In addition to the higher flow stress at low temperature an early decrease in flow stress at higher temperature is also found in fine-grained samples in comparison with their coarse-grained counterparts. This softening is ascribed to the early dynamic recrystallization or grain boundary glide.
基金the financial support of the National Natural Science Foundation of China(Grant No.51101030)the Fundamental Research Funds for the Central Universities(Grant No.N100702001)
文摘Texture evolution in nickel, copper and α-brass that are representative of face-centered-cubic （fcc） materials with different stacking fault energy （SFE） during cold rolling was systematically investigated. X-ray diffraction, scanning electron microscopy and electron backscatter diffraction techniques were employed to characterize microstructures and local orientation distributions of specimens at different thickness reductions. Besides, Taylor and Schmid factors of the {111} 〈110〉 slip systems and {111} 〈112〉 twin systems for some typical orientations were utilized to explore the relationship between texture evolution and deformation microstructures. It was found that in fcc metals with low SFE at large deformations, the copper-oriented grains rotated around the 〈110〉 crystallographic axis through the brass-R orientation to the Goss orientation, and finally toward the brass orientation. The initiation of shear banding was the dominant mechanism for the above-mentioned texture transition.
基金supported by the National Natural Science Foundation(Nos.41172099,41272130)
文摘Study of dolomite texture can contribute to understanding the process of dolomitization.This research reports textures and homogenization temperatures of dolomites from the Permian-Triassic strata in the Sichuan Basin and the Lower Paleozoic strata in the Tarim Basin,which provided insights into relationships between dolomite textures and their formation temperatures.Our results are summarized as follows：1） dolomites with well-preserved texture indicate low dolomitization temperature.However,in certain diagenetic environments,the hydrothermal dolomitization may completely or partially preserve the original texture of dolomites.2） The formation temperatures of non-planar dolomites are always higher than those of planar dolomites.3） The formation temperatures of dolomite cements are generally higher than those of replacive dolomites.4） Although the formation temperatures of saddle dolomite cements have a wide range,they show higher values than those of the planar subhedral to euhedral dolomite cements.Thus,saddle dolomites could generally be an indicator of high precipitation temperature.5） The fluid Mg/Ca ratio is another element controlling dolomite morphology.Micritic dolomites,which precipitate from hypersaline fluids with a high Mg/Ca ratio in a subaerial environment could also have features of non-planar anhedral crystal shape because of rapid nucleation and crystallization during dolomitization.
