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Effects of Crystal Orientations and Grain Boundaries on Nanoindentation Behavior of γ-TiAl Alloys
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作者 Niu Wenshuai Li Haiyan +5 位作者 Zeng Linghao Cao Hui Chen Wenke Han Chenyang Feng Ruicheng Chen Tao 《稀有金属材料与工程》 北大核心 2026年第4期899-913,共15页
To elucidate the deformation mechanisms ofγ-TiAl,the nanoindentation experiments and crystal plasticity finite element(CPFE)simulation were employed to investigate the effects of crystal orientations and GBs on the m... To elucidate the deformation mechanisms ofγ-TiAl,the nanoindentation experiments and crystal plasticity finite element(CPFE)simulation were employed to investigate the effects of crystal orientations and GBs on the mechanical properties ofγ-TiAl alloys.A crystal plasticity constitutive model was developed,and load-displacement curves,hardness,and Young's modulus were obtained for both single grains and GBs inγ-TiAl alloys.Based on the aforementioned model,this study investigated the distribution patterns of surface morphology around the indentation sites of individual grain and GBs.It also analyzed the cumulative shear strain distribution,slip system activation,and the interaction between GBs and dislocation slip for various crystal orientations.The results indicate that the mechanical response and pileup behavior exhibit significant anisotropy due to the interplay among the indenter geometry,material slip systems,and cumulative shear strain distribution.Moreover,the interaction between GBs and dislocation slip substantially alters dislocation distribution,thereby influencing material flow and playing a critical role in the mechanical response and plastic deformation of the material. 展开更多
关键词 grain boundary NANOINDENTATION ANISOTROPY crystal orientation CPFE
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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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Micromechanical behavior and heterogeneous deformation induced hardening of a novel orientationheterostructured Mg-Y alloy
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作者 Yuliang Yang Yuxin Liu +5 位作者 Zhufeng He Ye Yuan Lifang Sun Hao Zhou Shuang Jiang Nan Jia 《Materials Futures》 2026年第2期1-23,共23页
Magnesium alloys usually exhibit poor ductility because of their limited slip systems at room temperature.To overcome this intrinsic limitation,heterostructure design has emerged as an effective strategy for enhancing... Magnesium alloys usually exhibit poor ductility because of their limited slip systems at room temperature.To overcome this intrinsic limitation,heterostructure design has emerged as an effective strategy for enhancing their mechanical performance,yet the development of orientation-based heterogeneous magnesium alloys remains relatively unexplored.In this work,by varying the triaxial cyclic compression(TCC)applied to an extruded Mg-2.9Y(wt.%)alloy,we obtained two materials that possessed comparable bimodal grain-size characteristics but showed notable differences in orientation heterogeneity.The material processed by TCC along three orthogonal directions for five complete cycles exhibited a predominantly hard orientation,with hard refined grains embedded within coarse grains of the same hard orientation.By applying an additional compression to plane A,the other material mainly comprising the soft orientation was obtained,with hard-oriented refined grains embedded in soft-oriented coarse grains.These materials exhibited quite different tensile properties and work hardening abilities.By combining microstructural characterization and crystal plasticity modeling,deformation micromechanism of the materials under tensile loading was explored.In the former,poor deformation coordination between the different domains led to strain localization in the refined grain region.However,the latter experienced a significant orientation transition due to tensile twinning.This promoted non-basalslip and improved deformation compatibility,resulting in the more persistent hetero-deformation induced hardening.These findings provide fundamental insights into the micromechanical behavior of heterostructured alloys and offer a new strategy for designing high-performance hexagonal close-packed materials by introducing heterogeneous orientation distributions. 展开更多
关键词 magnesium alloy heterogeneous microstructure orientation crystal plasticity modeling
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Enhanced Piezoelectric Output and Electromechanical Response of ZnO Film Sensors via Orientation Induction and Rapid Deposition Strategies
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作者 Zhonghao Liu Peiyun Li +10 位作者 Hulin Liu Zhiqi Feng Shuren Guo Xuanpu Dong Shang Li Nanjie Sun Chuanfei Guo Bin Hu Yanxiang Chen Yong Yan Huatang Cao 《Energy & Environmental Materials》 2026年第1期385-399,共15页
Zinc oxide(ZnO)films,as representative piezoelectric semiconductors,have garnered considerable interest in ultrasonic testing.Current research challenges include maintaining the consistency of continuous c-axis orient... Zinc oxide(ZnO)films,as representative piezoelectric semiconductors,have garnered considerable interest in ultrasonic testing.Current research challenges include maintaining the consistency of continuous c-axis orientation and determining the fundamental link between the electrical structure and piezoelectric response.Accordingly,we have proposed ZnO films incorporated with an orientation-inducing layer(OIL),utilizing orientation induction and rapid deposition technology to regulate the growth structure of the ZnO films.Furthermore,the influence of the competitive mechanism between the film growth and lateral diffusion on the film's growth structure has been investigated.Piezoelectric force microscopy(PFM)analysis demonstrated the regulation and enhancement of ZnO piezoelectric polarization by the OIL.The enhancement mechanism of OIL on film performance was revealed via experimental examination of the film structure,morphology,crystallization orientation,oxygen vacancies,carrier concentration,band structure,and density of states based on density functional theory(DFT).Benefiting from the superior electromechanical response of the ZnO OIL sensor,characterized by fast response recovery times of 2.4 ms/7.7 ms and a sensitivity of 1.09 V/N,the device has successfully demonstrated practical applications in both motion pressure detection and bolt axial force measurement.These findings provide new insights into the ultrasonic detection for aerospace applications of ZnO OIL piezoelectric devices and demonstrate significant potential for health monitoring in connection systems. 展开更多
关键词 electromechanical response electronic structure orientation induction piezoelectric sensor ZnO films
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Stress-rupture behavior of a Ni-based Re-containing single crystal superalloy in[001]and[111]orientations at 1100℃
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作者 Guang-lei Wang Dong-qing Qi +1 位作者 Jin-lai Liu Ji-de Liu 《China Foundry》 2026年第2期179-185,共7页
Turbine blades,due to their intricate geometry,are exposed to multiaxial stresses during operation.Consequently,it is imperative to examine the anisotropy of their stress-rupture behavior across various testing scenar... Turbine blades,due to their intricate geometry,are exposed to multiaxial stresses during operation.Consequently,it is imperative to examine the anisotropy of their stress-rupture behavior across various testing scenarios,particularly under high-temperature conditions.Stress-rupture behavior of a Ni-based single crystal superalloy was investigated under a load varying from 100 MPa to 137 MPa at 1,100℃ for both[001]-and[111]-orientated specimens.Results demonstrate that the rupture behavior of[111]-orientated specimens exhibits obviously higher sensitive to applied stress compared to[001]-orientated specimens.This difference is primarily attributed to the orientation dependentγ'coarsening behavior and distinct dislocation interactions atγ/γ'interfaces.In[001]-oriented specimens,plate-likeγ/γ'rafts rapidly form alongside well-developed interfacial dislocation networks,where theγ/γ'misfit stress dominates the microstructural evolution.In contrast,the[111]-orientated specimens exhibit retained,coarsenedγ'precipitates embedded within theγmatrix,accompanied by poorly developed interfacial dislocation networks. 展开更多
关键词 Ni-based single crystal superalloy stress-rupture behavior deformation mechanism stress dependence orientation dependence
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Evolution of grain orientation and slip mode in gradient AZ31 magnesium alloy sheets with multiple texture components
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作者 Wen-tao NIU Feng LI +2 位作者 Jia-yang ZHANG Lu SUN Zi-yi WANG 《Transactions of Nonferrous Metals Society of China》 2026年第3期766-779,共14页
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
关键词 hard plate rolling AZ31 magnesium alloy sheet gradient structure texture components grain orientation
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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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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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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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Determination of Fracture Plane Orientation Using the Variance Method under Multiaxial Loading
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作者 Mbaiyelkom Esdras Ngargueudedjim Kimtangar +2 位作者 Bianzeube Tikri Kenmeugne Bienvenu Fogue Médard 《Open Journal of Applied Sciences》 2025年第2期411-424,共14页
The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained expe... The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained experimentally through tests on specimens under multiaxial loading with that calculated by the variance method. In the statistical approach criteria, several methods have been developed but we have presented only one method, namely the variance method using the equivalent stress. She assumes that the fracture plane orientation is the one on which the variance of the equivalent stress is maximum. Three types of equivalent stress are defined for this method [1]: normal stress, shear stress and combined normal and shear stress. The results obtained were compared with experimental results for multiaxial cyclic stress states, and it emerges that the variance method for the case of combined loading is conservative as it gives a better prediction of the fracture plane. 展开更多
关键词 Biaxial Fatigue Fracture Plane orientation Critical Fracture Plane Variance Method Fatigue Criteria
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Orientation Parameters Estimation and Lens Distortion Correction for UAVs Photogrammetry with Non-metric Cameras
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作者 DENG Xingsheng GAO Yang ZHU Xu 《Journal of Geodesy and Geoinformation Science》 2025年第1期71-88,共18页
The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogram... The estimation of orientation parameters and correction of lens distortion are crucial problems in the field of Unmanned Aerial Vehicles(UAVs)photogrammetry.In recent years,the utilization of UAVs for aerial photogrammetry has witnessed a surge in popularity.Typically,UAVs are equipped with low-cost non-metric cameras and a Position and Orientation System(POS).Unfortunately,the Interior Orientation Parameters(IOPs)of the non-metric cameras are not fixed.Whether the lens distortions are large or small,they effect the image coordinates accordingly.Additionally,Inertial Measurement Units(IMUs)often have observation errors.To address these challenges and improve parameter estimation for UAVs Light Detection and Ranging(LiDAR)and photogrammetry,this paper analyzes the accuracy of POS observations obtained from Global Navigation Satellite System Real Time Kinematic(GNSS-RTK)and IMU data.A method that incorporates additional known conditions for parameter estimation,a series of algorithms to simultaneously solve for IOPs,Exterior Orientation Parameters(EOPs),and camera lens distortion correction parameters are proposed.Extensive experiments demonstrate that the coordinates measured by GNSS-RTK can be directly used as linear EOPs;however,angular EOP measurements from IMUs exhibit relatively large errors compared to adjustment results and require correction during the adjustment process.The IOPs of non-metric cameras vary slightly between images but need to be treated as unknown parameters in high precision applications.Furthermore,it is found that the Ebner systematic error model is sensitive to the choice of the magnification parameter of the photographic baseline length in images,it should be set as less than or equal to one third of the photographic baseline to ensure stable solutions. 展开更多
关键词 UAVs photogrammetry non-metric cameras Interior orientation Parameters(IOPs) Exterior orientation Parameters(EOPs) lens distortion correction
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A Study on the Impact of College Counselors on College Students’Career Planning Based on Role Orientation and Path Optimization
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作者 Ningjing Wang 《Journal of Contemporary Educational Research》 2025年第11期144-149,共6页
This paper discusses the key significance of college students’career planning and development in China,focusing on analyzing the role orientation of counselors and their functions in this process.Combined with the co... This paper discusses the key significance of college students’career planning and development in China,focusing on analyzing the role orientation of counselors and their functions in this process.Combined with the core content of career planning,the study explores how counselors can assist students’career development through various approaches,including awakening career awareness,enhancing self-cognition,and promoting career exploration.The specific implementation paths cover classroom teaching,thematic training,second classroom activities,the construction of“one-stop”student communities,and personalized heart-to-heart talks,so as to give full play to the role of counselors in career guidance. 展开更多
关键词 COUNSELORS Role orientation Career planning
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Origin of misorientations for fcc→hcp transformation in pure cobalt and its in-situ validation
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作者 Jin-jiang HE Guo-jin XU +4 位作者 Xing-quan WANG Jun-feng LUO Dan LIU Yong-jun LI Xin-fu GU 《Transactions of Nonferrous Metals Society of China》 2025年第5期1532-1542,共11页
The origin of the misorientations after fcc(face-centered cubic)to hcp(hexagonal close-packed)transformation in pure cobalt was elucidated by utilizing the electron backscatter diffraction(EBSD)technique and transform... The origin of the misorientations after fcc(face-centered cubic)to hcp(hexagonal close-packed)transformation in pure cobalt was elucidated by utilizing the electron backscatter diffraction(EBSD)technique and transformation crystallographic models.It is found the Shoji−Nishiyama orientation relationship during fcc→hcp transformation leads to four hcp variants,characterized by a common misorientation angle of 70.5°with respect to the<1120>direction,which is the predominant misorientation observed.Other statistically significant misorientation angles between hcp grains,including 32°,36°,38°,60°,71°and 86°−91°,are also identified.These newly observed misorientation angles are linked to the microstructure of the fcc matrix at elevated temperatures,with twin structures in the fcc matrix being the primary cause.Furthermore,a novel method is proposed for estimating the fraction of twins in the fcc grains based on misorientation angles between hcp variants,which is found to be consistent with experimental observations.In-situ EBSD observations validate the possible origin of fcc twins from the hcp→fcc transformation. 展开更多
关键词 COBALT transformation crystallography VARIANT orientation relationship twin
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Stepwise control of molecular packing orientation and order in non-fullerene acceptors using dual additives for high-efficiency organic solar cells
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作者 Liang Bai Sein Chung +8 位作者 Zhenmin Zhao Jeng-Hun Lee Seung Hyun Kim Yuan Liu Lixing Tan Jiancheng Zhong Jingrong Zhang Kilwon Cho Zhipeng Kan 《Journal of Energy Chemistry》 2025年第11期962-972,I0021,共12页
The performance of organic solar cells is significantly influenced by the acceptor molecular packing properties within the active layers,which is essential for optimizing charge dynamics and photovoltaic performance.H... The performance of organic solar cells is significantly influenced by the acceptor molecular packing properties within the active layers,which is essential for optimizing charge dynamics and photovoltaic performance.However,achieving precise control over this packaging structure presents a considerable challenge.Herein,we propose a dual additive strategy utilizing dibenzofuran and halogenated naphthalene to systematically manipulate molecular packing orientation and enhance the long-range molecular packing order of the acceptors.Dibenzofuran is crucial in promoting crystallinity within the material,facilitating the formation of an ordered structure,while halogenated naphthalene regulates the orientation of the molecules,ensuring proper alignment.Specifically,the combination of dibenzofuran and 1-chloronaphthalene promotes edge-on molecular packing and enhances the formation of nanofibrillar structures with improved order,leading to improved charge transport and device performance.Implementing this strategy in devices composed of PM6 and L8-BO has yielded a power conversion efficiency of 19.58%,accompanied by long-term stability.Similarly,1-fluoronaphthalene has also demonstrated effectiveness in improving molecular orientation and overall device efficiency,demonstrating the robustness of this dual additive strategy.By addressing the challenges associated with molecular packing and orientation in active layers,our result contributes valuable insights into optimizing organic solar cells for practical applications. 展开更多
关键词 Molecular orientation Dual additives Fibril morphology Molecular order
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The effect of secondary dendrite orientation on thickness debit effect of nickel-based single-crystal superalloy with tubular samples
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作者 Jing Liu Minghan Yu +6 位作者 Shiling Min Gong Zhang Zhengguo Xu Xingang Liu Li Wang Jiasheng Dong Langhong Lou 《Journal of Materials Science & Technology》 2025年第14期80-92,共13页
Secondary dendrite orientation and wall thickness considerably affect the stress rupture life of thin-walled samples.However,the effect of the secondary dendrite orientation on the thickness debit effect of nickel-bas... Secondary dendrite orientation and wall thickness considerably affect the stress rupture life of thin-walled samples.However,the effect of the secondary dendrite orientation on the thickness debit effect of nickel-based single-crystal superalloys has not been thoroughly investigated until now.Owing to geometrical constraints,typical sheet samples cannot reveal the mechanism responsible for the thickness debit effect in turbine blades.This study examined the effect of secondary dendrite orientation on the thickness debit effect of nickel-based single-crystal superalloys at 1100℃/137 MPa in tubular samples.As the wall thickness decreased from 1.5 mm to 0.3 mm,the stress rupture life decreased from approximately 170 h to 64 h,demonstrating a noticeable thickness debit effect.Among the different secondary dendrite orientation areas,the variation in plastic deformation difference increased from 7%(1.5 mm)to 45%(0.5 mm)and subsequently decreased to 4%(0.3 mm).In thinner samples,the thickness contraction and microstructure evolution were more pronounced in the[100]areas than that in the[110]and[210]areas.The theoretical calculation quantitatively indicated that for the effective stress increased,the contribution of plastic deformation(45%)was slightly lower than that of oxidation(55%)in 0.3 mm samples;nevertheless,plastic deformation played a prominent role in 0.5,0.8,1,and 1.5 mm samples and increased from 61%(0.5 mm samples)to 85%(1.5 mm samples).In thinner samples,the larger plastic deformation in the secondary dendrite orientation of the[100]areas and oxidation increased the effective stress,resulting in a shorter rupture life.These findings are conducive to the structural optimization and performance improvement of turbine blades. 展开更多
关键词 SUPERALLOY CREEP Secondary dendrite orientation Thickness debit effect SLIP
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A Comparative Study of Domestic and International Linear Algebra Curriculum Design and Application Orientation
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作者 Peilong Zhang 《Journal of Contemporary Educational Research》 2025年第11期257-263,共7页
This paper presents a systematic comparison of the curriculum design and application orientation of the linear algebra curriculum in our country and abroad.It explains mainly differences in course objectives,teaching ... This paper presents a systematic comparison of the curriculum design and application orientation of the linear algebra curriculum in our country and abroad.It explains mainly differences in course objectives,teaching content,approaches,and feedback mechanisms,reflecting divergent understandings of the discipline’s value within distinct educational ecosystems.Forward-looking and practical conclusions are proposed across five main directions:optimizing course structure,strengthening practical components,deepening interdisciplinary integration,building faculty capacity,and developing teaching resources.The aim is to provide strong conceptual help and realistic guidance for getting real progress in linear algebra education in China. 展开更多
关键词 Linear algebra Curriculum design Application orientation Teaching reform
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Unleashing high-efficiency mass-charge transfer in Bi OBr anodes for aqueous batteries via targeted(110)plane orientation
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作者 Hanqing Liu Tingting Y.K.Qin +8 位作者 Yingguang Zhang Xiaolong Zhao Wei Dong Zhenfei Chang Sarah K.W.Leong Rafa Zarin Meng Ni Dennis Y.C.Leung Wending Pan 《Journal of Energy Chemistry》 2025年第4期749-758,共10页
Bismuth oxybromide(BiOBr)is being actively researched as a promising anode material for aqueous batteries due to its unique layered structure,which theoretically allows for efficient ion diffusion.However,current stud... Bismuth oxybromide(BiOBr)is being actively researched as a promising anode material for aqueous batteries due to its unique layered structure,which theoretically allows for efficient ion diffusion.However,current studies have come across many challenges,e.g.serious capacity degradation and inferior rate capability caused by severe structural collapse and sluggish reaction kinetics,highlighting the need for further improvement in efficient utilization of the layered space.Herein,this study employs a novel crystal orientation regulation to enhance the performance of BiOBr electrode by a facile solvothermal method to efficiently utilize the interlayered structu re.The delicate design of BiOBr(BOB)succeeds in maximizing the exposed(110)crystalline plane,providing efficient pathways for ion diffusion and streamlining the mass migration process.Moreover,the optimized band structure and the formation of oxygen vacancies in this designed material have been found,enabling high electrical conductivity,accelerating the charge transfer process and facilitating rapid reaction rate.Owing to the simultaneously enhanced mass transfer at the interlayers and the charge transfer during the phase conversion process,the BOB-110 electrode exhibits exceptional electrochemical performances,boasting impressive charge storage and rate capability(159 mAh g^(-1)at 4 A g^(-1)),and outstanding cycling stability of capacity retention around 75%(119 mAh g^(-1))even after 1000 cycles at a high current density of 4 A g^(-1).These findings underscore the substantial potential of BiOBr electrodes for future energy storage devices such as wearable electronics and power grids where the power output,lifespan,and affordability are simultaneously required. 展开更多
关键词 Aqueous battery BiOBr Crystal orientation Energy band structure
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Strength-based concurrent design for structural topology and building orientation of additively manufactured lattice structure
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作者 Chenyang LI Yamin LI +3 位作者 Shangqin YUAN Shaoying LI Jihong ZHU Weihong ZHANG 《Chinese Journal of Aeronautics》 2025年第9期540-558,共19页
A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and ... A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and structural yield strength can be simultaneously adjusted by integrating the overall process-structure-performance relationship of the AM process into the optimization.Specifically,the transverse isotropic material model is adopted to describe the material properties induced by the layer-by-layer manner of additive manufacturing.To bolster lattice strength performance,the stress constraints and ratio constraints of lattice struts are employed.The Tsai-Wu yield criterion is implemented to characterize the lattice strut's strength,while the P-norm method streamlines the handling of multiple constraints,minimizing computational overhead.Moreover,the gradient-based optimization model is established,where both the individual struts diameters and BO can be designed,and the buckling-prone spatial struts are strategically eliminated to improve the lattice strength further.Furthermore,several typical structures are optimized to verify the effectiveness of the proposed method.The optimized results are quite encouraging since the heterogeneous lattice structures with optimized BO obtained by the strength-based concurrent method show a remarkably improved performance compared to traditional designs. 展开更多
关键词 Strength-based design AM-driven design Concurrent design Building orientation Additive manufacturing
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