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Orientation-and wavelength-dependent sperm motility in optical trapping
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作者 Juan Wang Jifu Lyu +8 位作者 Haoyu Pan Xinyu Fan Xiang Jiang Xuhui Bao Yi Wang Fengya Lu Zhiguo Zhang Zhensheng Zhong Jinhua Zhou 《Journal of Innovative Optical Health Sciences》 2026年第2期54-68,共15页
Optical tweezers technology has the characteristics of noncontact manipulation in three dimensions and steerable separation in solutions,and could be applied to obtain a separated sperm with high quality for intracyto... Optical tweezers technology has the characteristics of noncontact manipulation in three dimensions and steerable separation in solutions,and could be applied to obtain a separated sperm with high quality for intracytoplasmic sperm injection(ICSI).However,the effects of optical tweezers on sperm motility are still unclear.To elucidate the effects on sperm motility for optical tweezers,we systematically investigated the correlation between motility parameters and the parameters of optical tweezers(wavelength,power,trapping duration,and trapping orientation).Under three systems of optical tweezers with different laser wavelengths(1064,850,and 785 nm),the nine motility parameters of free swimming were mainly affected by trapping orientation(vertical/horizontal)and trapping duration.When 850 nm laser and 1064 nm laser are used,vertical trapping significantly reduces sperm free-swimming capability with prolonged exposure time,whereas horizontal trapping exhibits relatively minor interference on sperm motility.Notably,the 785 nm laser does not induce statistically significant changes in key parameters of sperm motility under any experimental conditions(trapping orientation and duration).For the rolling frequency of trapped sperm,horizontal trapping for three wavelengths has a negligible effect compared with vertical trapping,especially for the 785 nm laser.In conclusion,horizontal trapping can preserve sperm motility under low power(below 140mW at 1064 nm,below 100mW at 850nm,below 60mW at 785 nm)and short duration(below 4 min).This trapping duration is suffcient for the separation procedure of single live sperm in ICSI.This study provides critical parameter optimization guidelines for the safe application of optical tweezers technology in reproductive medicine. 展开更多
关键词 Optical tweezers SPERM wavelength trapping duration trapping orientation
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The Relationship between Peer Victimization and Non-Suicidal Self-Injury Behavior among Middle School Students:The Mediating Role of Future Orientation and Social Withdrawal
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作者 Biao Li Xiao Hu +1 位作者 Pengzhan Wei Yunbin Deng 《International Journal of Mental Health Promotion》 2026年第2期157-170,共14页
Objectives:Non-suicidal self-injury(NSSI)represents a prominent and escalating concern within mental health,associated with considerable psychological and physical dangers.Peer victimization is identified as a signifi... Objectives:Non-suicidal self-injury(NSSI)represents a prominent and escalating concern within mental health,associated with considerable psychological and physical dangers.Peer victimization is identified as a significant predictor of NSSI behavior.Although prior research has explored the association between peer victimization and NSSI,the mechanisms underlying this relationship remain insufficiently understood.Utilizing social information processing theory frameworks,the present study seeks to examine the sequential mediating roles of a cognitive factor,future orientation,and a behavioral factor,social withdrawal,in middle school students.Methods:A cross-sectional survey was administered in China,involving 528 participants(261 females and 267 males;Meanage=13.71,standard deviation[SD]=0.93).Participants completed self-report measures assessing peer victimization via the Delaware Bullying Victimization Scale-Student Version,NSSI via the Adolescents Self-Harm Scale,future orientation via the Adolescent Future Orientation Questionnaire,and social withdrawal via the Social Withdrawal Questionnaire.Results:Findings indicated a significant positive correlation between peer victimization and NSSI(r=0.30,p<0.01).Additionally,future orientation and social withdrawal functioned as serial mediators,with an indirect effect of 0.01(95%CI:[0.01,0.02]),representing 2.70%of the total effect(𝛽=0.37,95%CI:[0.25,0.47]).Conclusions:The findings endorse a theoretical framework in which negative future outlook and social withdrawal are sequentially linked within the relationship between peer victimization and NSSI.Although the serial indirect effect observed is modest,it delineates a distinct associative pattern that characterizes adolescents subjected to victimization.These results carry practical significance for school-based intervention programs,indicating that targeting future perspectives and social connections may enhance strategies for preventing NSSI. 展开更多
关键词 Peer victimization non-suicidal self-injurious future orientation social withdrawal
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Effects of initial spin orientation on the generation of polarized electron beams from laser wakefield acceleration in plasma
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作者 L.R.Yin X.F.Li +6 位作者 Y.J.Gu N.Cao Q.Kong M.Büscher S.M.Weng M.Chen Z.M.Sheng 《Matter and Radiation at Extremes》 2026年第1期20-28,共9页
The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of... The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of the initial spin direction,the spin dynamics of the electron beam are found to depend on the self-injection mechanism.The effects of wakefields and laser fields are studied using test particle dynamics and particle-in-cell simulations based on the Thomas-Bargmann-Michel-Telegdi equation.Compared with transverse injection,longitudinal injection is found to be preferable for obtaining a highly polarized electron beam. 展开更多
关键词 spin dynamics laser fields test particle dynamics initial spin orientation electron beam laser wakefield acceleration electron beam polarization
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EFFECT OF COMPATIBILITY ON PHASE MORPHOLOGY AND ORIENTATION OF ISOTACTIC POLYPROPYLENE (IPP) BLENDS OBTAINED BY DYNAMIC PACKING INJECTION MOLDING 被引量:3
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作者 傅强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第4期379-387,共9页
The effect of compatibility on phase morphology and orientation of isotactic polypropylene (iPP) blends under shear stress was investigated via dynamic packing injection molding (DPIM). The compatibility of iPP bl... The effect of compatibility on phase morphology and orientation of isotactic polypropylene (iPP) blends under shear stress was investigated via dynamic packing injection molding (DPIM). The compatibility of iPP blended with other polymers, namely, atactic polypropylene (aPP), octane-ethylene copolymer (POE), ethylene-propylene-diene rubber (EPDM) and poly(ethylene-co-vinyl acetate) (EVA), have first been studied using dynamic mechanical analysis (DMA). These blends were subjected to DPIM, which relies on the application of shear stress fields to the melt/solid interfaces during the packing stage by means of hydraulically actuated pistons. The phase morphology, orientation and mechanical properties of the injection-molded samples were characterized by SEM, 2D WAXS and Instron. For incompatible iPP/EVA blends, a much elongated and deformed EVA particles and a higher degree of iPP chain orientation were observed under the effect of shear. However, for compatible iPP/aPP blends, a less deformed and elongated aPP particles and less oriented iPP chains were deduced. It can be concluded that the compatibility between the components decreases the deformation and orientation in the polymer blends. This is most likely due to the hindering effect, resulting from the molecular entanglement and interaction in the compatible system. 展开更多
关键词 Compatibility Phase morphology orientation Stress.
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Crystal orientation and morphology of a lamellae in wrought titanium alloys: On the role of microstructure evolution in b processing 被引量:6
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作者 Huojun ZHENG Xiaoguang FAN +1 位作者 Xiang ZENG Rui ZUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第5期1305-1313,共9页
To obtain high-quality aviation forgings of titanium alloys, b forging is an essential processing step which must be considered throughout a production process. In this work, the effect of b forging on the crystal ori... To obtain high-quality aviation forgings of titanium alloys, b forging is an essential processing step which must be considered throughout a production process. In this work, the effect of b forging on the crystal orientation and morphology of lamellar a was experimentally investigated in a two-phase titanium alloy. Strong dynamic recovery during b working resulted in the formation of low-angle grain boundary(LAGBb) inside b grains. The lamellar a can penetrate through the LAGBb, leading to similar intra a LAGBs on subgrain boundaries. Deformation banding occurs at high strain rates, and both diffusive and sharp boundaries of deformation bands can be observed.A continuous change of the b orientation in diffusive boundaries results in the formation of fine and disordered a lamellae without intra-lamellar boundary to hold the Burgers orientation relationship(OR). On sharp boundaries, it is prone to producing continuous grain boundary a(aGB) with a highly similar orientation along the boundaries. Meanwhile, there may exist several lower-angle boundaries within the grain boundary a for a smoother orientation change on the b grain boundary. 展开更多
关键词 b FORGING BURGERS orientation relationship Crystal orientation Deformation band LAMELLAR a Titanium alloy
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Three dimensional dendritic morphology and orientation transition induced by high static magnetic field in directionally solidified Al-10wt.%Zn alloy 被引量:2
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作者 Sansan Shuai Xin Lin +4 位作者 Yuanhao Dong Long Hou Hanlin Liao Jiang Wang Zhongming Ren 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第8期1587-1592,共6页
Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back... Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back-scattered Diffraction(EBSD) and X-ray Diffraction(XRD). The application of high static axial magnetic field(5T) during directional solidification was found to destabilize the solid/liquid interface and cause the growth direction of dendrite deviate from thermal gradient, leading to irregular solid/liquid interfacial shape and cellular to dendritic morphology transition. The thermoelectric magnetic convection(TEMC) caused by the interaction of thermoelectric effect and magnetic field was supposed to be responsible for the transition. In addition, the EBSD and XRD results confirm that the preferred growth direction of α-Al was found to transform from the traditionally expected <100> to<110>. The dendrite orientation transition(DOT) in Al-10 wt.%Zn alloy can be attributed to the effect of applied magnetic field on the anisotropy of crystal during solidification. The result indicates the potential application of high static magnetic field in altering the morphology and preferred growth direction of dendrite during directional solidification. 展开更多
关键词 AL-ZN ALLOY HIGH static magnetic field Three-dimensional DENDRITE morphology DENDRITE orientation TRANSITION X-ray computed tomography
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Surface morphology and crystal orientation of electrodeposited tungsten coatings with different pulse parameters 被引量:2
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作者 Xian-Qin Fang Ying Zhang +4 位作者 Kai-Gui Zhu Wen-Jia Han Jian-Gang Yu Zhe Chen Hui-Jun Shi 《Rare Metals》 SCIE EI CAS CSCD 2018年第5期407-412,共6页
This study was conducted to investigate the influence of pulse parameters on the surface morphology and crystal orientation of the tungsten coatings electrodeposited on pure copper substrates. The deposited coatings w... This study was conducted to investigate the influence of pulse parameters on the surface morphology and crystal orientation of the tungsten coatings electrodeposited on pure copper substrates. The deposited coatings were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS). SEM analysis indicates that pulse parameters have significant influences on the surface morphology of the deposited coatings. Meanwhile, the change in grain size of the tungsten coatings demonstrates that the change in frequency and duty cycle could cause the variation of nucleation rate and grain growth of deposits. Moreover, no obvious diffusion layer at the coating/substrate interface is found by line analysis of EDS. XRD results reveal that tungsten coatings are of bcc structure and the preferred orientation of the deposits varies with duty cycle and period. 展开更多
关键词 Tungsten coating ELECTRODEPOSITION Pulse parameters Crystal orientation Surface morphology
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ANALYSIS AND CHARACTERIZATION OF MICROSCOPIC MORPHOLOGY AND ORIENTATION STRUCTURE OF POLYANILINE POLYMERIZED IN A CONSTANT MAGNETIC FIELD 被引量:1
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作者 马利 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第4期487-492,共6页
Conductive polyaniline(PAn-_M and PAn-_O) doped with dodecylbenzene sulfonic acid(DBSA) was synthesized by using emulsion polymerization method in the presence of a constant magnetic field(0.4 T) and the absence of ma... Conductive polyaniline(PAn-_M and PAn-_O) doped with dodecylbenzene sulfonic acid(DBSA) was synthesized by using emulsion polymerization method in the presence of a constant magnetic field(0.4 T) and the absence of magnetic field, respectively.The effects of magnetic field on the microscopic morphology and orientation structure of PAn were generally analyzed and characterized by using transmission electron microscope(TEM),X-ray diffraction(XRD) and through the conductivity anisotropy of unit resistance of t... 展开更多
关键词 POLYANILINE Magnetic field orientation microstructure Anisotropic conductivity
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Analysis of crystallographic orientation and morphology of microstructure during hot working for an alpha/beta titanium alloy 被引量:4
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作者 Jianwei Xu Weidong Zeng +3 位作者 Dadi Zhou Wei Chen Shengtong He Xiaoyong Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第24期1-13,共13页
This work focuses on analysis of microstructure morphology and crystallographic orientation for Ti-17 alloy during hot working.The results show that alpha phase and beta phase influence each other and there is a coord... This work focuses on analysis of microstructure morphology and crystallographic orientation for Ti-17 alloy during hot working.The results show that alpha phase and beta phase influence each other and there is a coordinate deformation between them.The non-uniform deformation is observed under small deformation conditions.The observing area can be divided into small deformation zone(area L)and large deformation zone(area H).Both alpha and beta phases remain the initial morphology,and they have better capability of coordinate deformation in area L,while coordinate capability is weak in area H in which alpha phase is globularized.Correspondingly,the Burgers orientation relations are well preserved in area L,but the orientation relations are more or less destroyed in area H.Dynamic recovery is the main mechanism of beta phase evolution when height reduction is lower.By contrast,the continuous dynamic recrystallization(CDRX)of beta phase gradually dominates the deformation pattern as the deformation increases.An uniformly globularized alpha structure is obtained under large deformation condition.The unsynchronized rotation of alpha phase around<11-20>pole occurs during deformation,which leads to the uniform crystal structure inside the same alpha lamellae.This process is an important step of globularization of the lamellar structure. 展开更多
关键词 Ti-17 alloy Hot working Microstructure evolution Crystallographic orientation
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Morphology and orientation relationship of VC precipitates in HSLA steel 被引量:1
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作者 Shijian Yan Xiaoping Liu Wenhuai Tian 《Journal of University of Science and Technology Beijing》 CSCD 2006年第5期420-423,共4页
The morphology and distribution of VC precipitates in HSLA steel as well as the orientation relationship between VC precipitate and α-Fe were studied by transmission electron microscopy (TEM). The chemical composit... The morphology and distribution of VC precipitates in HSLA steel as well as the orientation relationship between VC precipitate and α-Fe were studied by transmission electron microscopy (TEM). The chemical composition of the VC precipitate was analyzed qualitatively by using analytical electron microscopy (AEM) equipped with an energy dispersive spectrum (EDS) system. The VC precipitate is needle-like in shape with a size of about 10 nm in length and is homogeneously dispersed in the α-Fe matrix. The smaller lattice misfit along the 〈100〉 lattice direction of α-Fe matrix leads to VC precipitate forming with its long axes nearly parallel to the 〈100〉 lattice direction of α-Fe matrix. It is confirmed that the orientation relationship between VC precipitate and α- Fe is the "N-W" orientation relation by selected area electron diffraction (SAED) patterns. 展开更多
关键词 VANADIUM micro-alloyed steels VC precipitation orientation relationship
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Morphology and orientation evolution of Cu_(6)Sn_(5)grains on(001)Cu and(011)Cu single crystal substrates under temperature gradient 被引量:4
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作者 Yuanyuan Qiao Xiaoying Liu +3 位作者 Ning Zhao Lawrence C M Wu Chunying Liu Haitao Ma 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第36期29-39,共11页
The morphology and orientation evolution of Cu_(6)Sn_(5)grains formed on(001)Cu and(011)Cu single crystal substrates under temperature gradient(TG)were investigated.The initial orientated prism-type Cu_(6)Sn_(5)grains... The morphology and orientation evolution of Cu_(6)Sn_(5)grains formed on(001)Cu and(011)Cu single crystal substrates under temperature gradient(TG)were investigated.The initial orientated prism-type Cu_(6)Sn_(5)grains transformed to non-orientated scallop-type after isothermal reflow.However,the Cu_(6)Sn_(5)grains with strong texture were revealed on cold end single crystal Cu substrates by imposing TG.The Cu_(6)Sn_(5)grains on(001)Cu grew along their c-axis parallel to the substrate and finally merged into one grain to form a fully IMC joint,while those on(011)Cu presented a strong texture and merged into a few dominant Cu_(6)Sn_(5)grains showing about 30°angle with the substrate.The merging between neighboring Cu_(6)Sn_(5)grain pair was attributed to the rapid grain growth and grain boundary migration.Accordingly,a model was put forward to describe the merging process.The different morphology and orientation evolutions of the Cu_(6)Sn_(5)grains on single crystal and polycrystal Cu substrates were revealed based on crystallographic relationship and Cu flux.The method for controlling the morphology and orientation of Cu_(6)Sn_(5)grains is really benefitial to solve the reliability problems caused by anisotropy in 3 D packaging. 展开更多
关键词 3D packaging Single crystal Cu Temperature gradient orientation Disregistry Grain boundary migration
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Orientation-Dependent Morphology and Evolution of Interfacial Dislocation Networks in Ni-Based Single-Crystal Superalloys:A Molecular Dynamics Simulation
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作者 Bin Chen Wen-Ping Wu Ming-Xiang Chen 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2021年第1期79-90,共12页
In this paper,the morphology and evolution of interfacial dislocation networks of(100),(110)and(111)interphases of Ni-based single-crystal superalloys are studied by molecular dynamics(MD)simulations.Three-dimensional... In this paper,the morphology and evolution of interfacial dislocation networks of(100),(110)and(111)interphases of Ni-based single-crystal superalloys are studied by molecular dynamics(MD)simulations.Three-dimensional cubic-type and sandwich-type models are chosen to explore the orientation-dependent morphology of dislocation networks,and their respective advantages and disadvantages are compared.From the simulations,it is observed that various lattice orientations and model types lead to different morphologies of dislocation networks.Based on the analysis of average atomic energy and dislocation characteristics,the(100)orientation model has a more regular dislocation network,lower energy and better stability than the(110)and(111)orientation models after MD relaxation,which are supported by previous experimental and numerical simulations.Moreover,the cubic-type model has lower energy and better stability than the sandwich-type model.This will be helpful for choosing a more appropriate and reasonable model for simulating the interfacial dislocation networks of Ni-based single-crystal superalloys. 展开更多
关键词 Ni-based single-crystal superalloys Molecular dynamics simulation orientation Interfacial dislocation networks
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MORPHOLOGY AND ORIENTATION CHARACTERISTICS OF DIRECTIONALLY SOLIDIFIED α(A1)-Mg_2Si EUTECTIC
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作者 S.P.Li S.X.Zhao +2 位作者 M.X Pan D.Q.Zhao X.C.Chen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第5期323-328,共6页
Dependence of the morphology of α(Al)-Mg2Si eutectic on the solidification velocity, and its orientation characteristics were investigated by thermoanalysis, directional solidification and electron diffraction techni... Dependence of the morphology of α(Al)-Mg2Si eutectic on the solidification velocity, and its orientation characteristics were investigated by thermoanalysis, directional solidification and electron diffraction techniques in this study.The eutectic morphology transformed from lamellae to rods with the increasing of the solidification velocity. Simultaneously, the orientation relationship changed from (100)Mg2Si/(100)Al;[110]Mg2si/[110]al to (011)Mg2si/(121)Al;[111]Mg2Si/[111]Al and (010)Mg2Si/(110)Al; [100]Mg2Si/[111]Al. Transformation of the eutectic morphology was related to the change of the preferred orientation of phase Mg2si. 展开更多
关键词 ?Al)-Mg2Si eutectic orientation directional solidification
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High-Precision and Ultraspeed Monitoring of Melt-Pool Morphology in Laser-Directed Energy Deposition Using Deep Learning 被引量:2
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作者 Jiayu Yang Guan Liu +4 位作者 Wei Zhu Yingjie Zhang Wenbin Zhou Defu Liu Yongcheng Lin 《Additive Manufacturing Frontiers》 2025年第2期81-89,共9页
Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessit... Laser-directed energy deposition(L-DED)is an advanced additive manufacturing technology primarily adopted in metal three-dimensional printing systems.The L-DED process is characterized by various defects,thus necessitating the extensive use of in-situ monitoring to enable real-time adjustments of process parameters by detecting molten-pool features.To address the challenge of accurately extracting the molten-pool morphology from an undetached spatter,an innovative monitoring method based on the U-Net(U-shaped network)is proposed herein.A lightweight architecture accelerates the processing speed,whereas an enhanced loss function incorporating weight maps augments the segmentation precision.The model performance is evaluated by comparing its segmentation accuracy and processing speed with those of the conventional U-Net,using the mean intersection over union(MIoU)as the segmentation metric.The improved model demonstrates superior segmentation accuracy at the interface between the molten pool and spatter,with a peak MIoU of 0.9798 achieved on the test set.Furthermore,this model processes each image in an extremely short time of 17.9 ms.Using this segmentation algorithm,the error in extracting the molten-pool width from single-track experiments is within 0.1 mm.The proposed method for monitoring the molten-pool morphology is suitable for deployment in online monitoring systems,thus providing a foundation for subsequent process-parameter regulation. 展开更多
关键词 Laser-directed energy deposition Molten-pool morphology Semantic segmentation Mean intersection over union(MIoU)
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Effect of Surface Treatment and Fiber Orientation on the Tensile and Morphological Properties of Banana Stem Fiber Reinforced Natural Rubber Composite 被引量:2
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作者 Ikechukwu Christian Ezema A. R. Ravindranatha Menon +1 位作者 Camelus Sunday Obayi Augustin Dinobi Omah 《Journal of Minerals and Materials Characterization and Engineering》 2014年第3期216-222,共7页
A mixture of NaOH and Na2SO3 was used in modification of banana stem fibers (BSF). Unidirectional BSF reinforced natural rubber (NR) lamina composites were made using compression moulding method. The results of the te... A mixture of NaOH and Na2SO3 was used in modification of banana stem fibers (BSF). Unidirectional BSF reinforced natural rubber (NR) lamina composites were made using compression moulding method. The results of the tensile loading in 0°, 45° and 90° to the fiber directions of the composite with fiber mass fraction of 30% were studied. Surface modification of the BSF with a mixture of 4% NaOH and 2% Na2SO3 increased the tensile strength and elastic modulus of the composite to 4.03 MPa and 147.34 MPa respectively from 3.12 MPa and 84.30 MPa of the untreated. Variation in properties due to fiber orintations was observed indicating a higher value of properties in the 0° fiber orientation than in 45° and 90° directions. The result of scanning electron microscope (SEM) micrographs of the surfaces of the fibers indicted an improvement in bonding of the fiber bundles prior to lamination with natural rubber as a result of surface treatment which resulted in its higher tensile strength. 展开更多
关键词 NATURAL FIBER BANANA FIBER NATURAL Rubber TENSILE Properties SEM FIBER orientation
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Integrating well logs,3D seismic,and earthquake data for comprehensive prediction of 3D in-situ stress orientations:A case study from the Weiyuan area in the Sichuan Basin,China 被引量:1
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作者 Huan Cao Yang Zhao +4 位作者 Hai-Chao Chen Le-Le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu 《Petroleum Science》 2025年第1期210-221,共12页
Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(F... Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs)derived from earthquake data and formation micro-imager(FMI)data from well logs.However,these techniques can be costly,depth-inaccurate,and may lack spatial coverage.To address this issue,we introduce the use of three-dimensional(3D)seismic data(active sources)as a lateral constraint to approximate the 3D stress orientation field.Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy,we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information.We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin,China,a region targeted for shale gas production.By integrating diverse datasets,including 3D seismic,earthquakes,and well logs,we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes).Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax)obtained from FMIs.We analyzed 12 earthquakes(magnitude>3)recorded between 2016 and 2020 for their FMSs and compressional axis(P-axis)orientations.The derived SHmax direction from our 3D stress model is 110°ES(East-South),which shows excellent agreement with the FMSs(within 3.96°).This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations. 展开更多
关键词 In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager
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Morphology engineering of ZnO micro/nanostructures under mild conditions for optoelectronic application
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作者 Liang Chu Haoyu Shen +3 位作者 Hudie Wei Hongyu Chen Guoqiang Ma Wensheng Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期498-503,共6页
Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,si... Zinc oxide(ZnO)serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV.Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures,given its low cost,simplicity,and easy implementation.Moreover,ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process,particularly at room temperature.In this work,ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures(including room temperature).The formation of Zn^(2+)complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO,which resulted in various structures,such as nanoparticles,nanosheets,microflowers,and single crystals.Finally,the obtained ZnO was used in the optoelectronic application of ultraviolet detectors. 展开更多
关键词 morphology engineering low temperature ZnO nanosheets microflowers ultraviolet detector
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Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ) double perovskites as oxygen electrodes for solid oxide cells:Effect of chemical composition and electrospun morphology 被引量:1
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作者 Jacek Winiarski Piotr Winiarz Konrad Świerczek 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2628-2638,共11页
Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structur... Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode. 展开更多
关键词 multicomponent oxides double perovskites morphology modification ELECTROSPINNING oxygen electrodes solid oxide cells
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Influence of orientation of the intermediate principal stress on fracture reactivation in granite 被引量:1
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作者 Wei Wang Fanzhen Meng +6 位作者 Zhufeng Yue Guanghao Cui Qijin Cai Zhiyuan Li Dongliang Tian Hui Zhou Zaiquan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期859-876,共18页
Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation pr... Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation process under two different orientations of σ_(2),i.e.σ_(2) parallel to the fracture plane(Scheme 2)and σ_(2) cutting through the fracture plane(Scheme 3),under varying σ_(3) from 10 MPa to 40 MPa.The peak or fracture reactivation strength,deformation,failure mode,and post-peak mechanical behavior of intact(Scheme 1)and pre-fractured(Schemes 2 and 3)specimens were also compared.Results show that for intact specimens,the stress remains nearly constant in the residual sliding stage with no stick-slip,and the newly formed fracture surface only propagates along the σ_(2) direction when σ_(3) ranges from 10 MPa to 30 MPa,while it extends along both σ_(2) and σ_(3) directions when σ_(3) increases to 40 MPa;for the pre-fractured specimens,the fractures are usually reactivated under all the σ_(3) levels in Scheme 2,but fracture reactivation only occurs when σ_(3) is greater than 25 MPa in Scheme 3,below which new faulting traversing the original macro fracture occurs.In all the test schemes,both ε_(2) and ε_(3) experience an accumulative process of elongation,after which an abrupt change occurs at the point of the final failure;the degree of this change is dependent on the orientation of the new faulting or the slip direction of the original fracture,and it is generally more than 10 times larger in the slip direction of the original fracture than in the non-slip direction.Besides,the differential stress(peak stress)required for reactivation and the post-peak stress drop increase with increasing σ_(3).Post-peak stress drop and residual strength in Scheme 3 are generally greater than those in Scheme 2 at the same σ_(3) value.Our study clearly shows that intermediate principal stress orientation not only affects the fracture reactivation strength but also influences the slip deformation and failure modes.These new findings facilitate the mitigation of dynamic geological hazards associated with fracture and fault slip. 展开更多
关键词 True triaxial Fracture reactivation Intermediate principal stress orientation Minimum principal stress levels Computed tomography
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Morphology and vegetation dynamics in a macro-tidal tropical estuary with high fluvial discharge:A case study of the Salween River Delta 被引量:1
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作者 HE Aoyang HUANG Jiangcheng SUN Zhengbao 《Journal of Geographical Sciences》 2025年第3期577-597,共21页
A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between ... A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas. 展开更多
关键词 high fluvial discharge macro-tidal estuary deltaic morphology intertidal vegetation Salween River Delta
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