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METHODS OF VISUAL RECOGNITION,POSITIONING AND ORIENTATING OF 3 D SIMPLE GEOMETRIC WORKPIECE
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作者 王向军 王以忠 叶声华 《Transactions of Tianjin University》 EI CAS 1998年第2期36-40,共5页
The methods of visual recognition,positioning and orienting with simple 3 D geometric workpieces are presented in this paper.The principle and operating process of multiple orientation run le... The methods of visual recognition,positioning and orienting with simple 3 D geometric workpieces are presented in this paper.The principle and operating process of multiple orientation run length coding based on general orientation run length coding and visual recognition method are described elaborately.The method of positioning and orientating based on the moment of inertia of the workpiece binary image is stated also.It has been applied in a research on flexible automatic coordinate measuring system formed by integrating computer aided design,computer vision and computer aided inspection planning,with a coordinate measuring machine.The results show that integrating computer vision with measurement system is a feasible and effective approach to improve their flexibility and automation. 展开更多
关键词 automatic measurement visual recognition visual positioning visual orientating coordinate measuring machine
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Mechanical Anisotropy of Ti-6Al-4V Alloy Fabricated by Selective Laser Melting
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作者 Liu Junwei Liu Zhenya +3 位作者 Fan Caihe Ou Ling He Wuqiang Ma Wudan 《稀有金属材料与工程》 北大核心 2026年第1期35-46,共12页
To explore the formation mechanism of anisotropy in Ti-6Al-4V alloy fabricated by selective laser melting(SLM),the compressive mechanical properties,microhardness,microstructure,and crystallographic orientation of the... To explore the formation mechanism of anisotropy in Ti-6Al-4V alloy fabricated by selective laser melting(SLM),the compressive mechanical properties,microhardness,microstructure,and crystallographic orientation of the alloy across different planes were investigated.The anisotropy of SLM-fabricated Ti-6Al-4V alloys was analyzed,and the electron backscatter diffraction technique was used to investigate the influence of different grain types and orientations on the stress-strain distribution at various scales.Results reveal that in room-temperature compression tests at a strain rate of 10^(-3) s^(-1),both the compressive yield strength and microhardness vary along the deposition direction,indicating a certain degree of mechanical property anisotropy.The alloy exhibits a columnar microstructure;along the deposition direction,the grains appear equiaxed,and they have internal hexagonal close-packed(hcp)α/α'martensitic structure.α'phase has a preferential orientation approximately along the<0001>direction.Anisotropy arises from the high aspect ratio of columnar grains,along with the weak texture of the microstructure and low symmetry of the hcp crystal structure. 展开更多
关键词 selective laser melting TI-6AL-4V ANISOTROPY crystal orientation
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Orientating structure of hydroxyls in 2 : 1 phyllosilicate
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作者 WANG Lin ZHANG Zhenyu 《Chinese Science Bulletin》 SCIE 1997年第4期321-324,共4页
ABBOTT et al. considered that there might be two types of hydroxyls with different site energies in the dioctahedral silicates. Giese holds a similar opinion. However, so far no detailed research has been done on the ... ABBOTT et al. considered that there might be two types of hydroxyls with different site energies in the dioctahedral silicates. Giese holds a similar opinion. However, so far no detailed research has been done on the orientating features, types and genesis of orientations 展开更多
关键词 orientating STRUCTURE of HYDROXYLS 2 PHYLLOSILICATE dioctahedral MINERALS trioctahedral MINERALS pyrophyllite.
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Recent advances in the properties,synthesis,and applications of oriented composite phase change materials
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作者 Jun Tong Zui Tao +5 位作者 Wenjie Hou Chaoxing Yang Tiantian Yuan Huimin Liao Xiubing Huang Ge Wang 《Journal of Energy Chemistry》 2026年第1期902-944,I0020,共44页
In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)r... In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs. 展开更多
关键词 Phase change materials Oriented phase change composites Oriented thermal conduction Thermal conductivity enhancements
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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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Automated recognition of rock discontinuity in underground engineering using geometric feature analysis
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作者 Adili Rusuli Xiaojun Li +1 位作者 Yuyun Wang Yi Rui 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1016-1033,共18页
Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,su... Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes. 展开更多
关键词 Underground engineering Rock mass discontinuity Orientation grouping Fisher distribution 3D point cloud Automated recognition
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The Wuhu Model:Sustainable Urban Renewal
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作者 ZHOU LIN 《China Today》 2026年第1期56-59,共4页
In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-qualit... In Wuhu,urban renewal has not only transformed the development process,but improved people’s lives.DURING the 14th Five-Year Plan period(2021-2025),urban renewal has served as a crucial measure to promote high-quality urban development and continuously meet people’s growing aspirations for a better life.Wuhu,in central China’s Anhui Province,has consistently enhanced its urban functions and services to build a modern,people-oriented city that is innovative,livable,beautiful,resilient,and smart. 展开更多
关键词 BEAUTY RESILIENCE people oriented city urban development enhanced its urban functions services sustainable urban renewal INNOVATION LIVABILITY
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Exposing Zn(002)Texture with Sucralose Additive for Stable and Dendrite-Free Aqueous Zinc-Ion Batteries
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作者 Feiyu Tao Yingke Ren +9 位作者 Li’e Mo Yifan Wang Yang Huang Hong Zhang Chengwu Shi Zhaoqian Li Jiaqin Liu Lei Chen Linhua Hu Yucheng Wu 《Nano-Micro Letters》 2026年第4期40-53,共14页
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
关键词 Aqueous zinc-ion batteries Zinc anode Oriented growth (002)texture
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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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Dynamic Mechanisms of Land Use Conflict Under Main Function Oriented Zone Planning:A Case Study of Beijing-Tianjin-Hebei Region
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作者 ZHENG Yang CHENG Linlin +2 位作者 WANG Junqi WANG Yifang CUI Huizhen 《Chinese Geographical Science》 2026年第2期320-336,共17页
Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains rel... Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains relatively limited.Focusing on the indirect driving role of policy on LUC,this study proposed County Development Level(CDL)under Major Function Oriented Zone Planning(MFOZP)guidance as an intermediary variable,bridging the implicit influence of MFOZP and the explicit changes in LUC.Using the Beijing-Tianjin-Hebei(BTH)region in China as a case study,we analyzed the spatio-temporal evolution characteristics of LUC and CDL for the periods 2000-2010 and 2010-2020,before and after MFOZP implementation.Panel models and Geographically Weighted Regression(GWR)were employed to explore the mechanism by which CDL influences LUC under MFOZP guidance.The results show that:1)MFOZP implementation effectively alleviates land use pressure from regional development,with LUC continuously declining at a rate of 2.41%,while CDL exhibits slight growth(3.84%),during 2010-2020.2)Under MFOZP guidance,CDL reduces pressure on Land Use Structure Conflict(LUSC)and Land Use Process Conflict(LUPC),enhances its inhibitory effect on Land Use Function Conflict(LUFC),and significantly contributes to LUC coordination,with notable spatial heterogeneity.3)The coupling relationship between CDL and LUC has improved post-implementation.Based on this,tailored LUC coordination strategies are proposed for different functional zones.This study confirms the effectiveness of MFOZP in coordinating LUC and provides a scientific reference for LUC research under policy frameworks and the governance of LUC in the BTH region. 展开更多
关键词 Land Use Conflict(LUC) Major Function Oriented Zone Planning(MFOZP) County Development Level(CDL) Beijing-Tianjin-Hebei(BTH)region China
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Detection of white matter microstructural changes in patients with systemic lupus erythematosus based on multiple diffusion models and related diffusion metrics
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作者 Zhenxing Li Huanhuan Li +5 位作者 Bailing Tian Huiyang Liu Yueluan Jiang Pingting Yang Guoguang Fan Hu Liu 《Neural Regeneration Research》 2026年第6期2467-2474,共8页
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle... Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms. 展开更多
关键词 diffusion kurtosis imaging diffusion tensor imaging mean apparent propagator neurite orientation dispersion and density imaging neuropsychiatric systemic lupus erythematosus return to axis probability return to origin probability superior longitudinal fasciculus-3 superior thalamic radiation tract-based spatial statistics white matter microstructure
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Decoding the Solitude:Solitude and Reliance on Feelings versus Reasons in Decision Making 被引量:1
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作者 HOU Jia-wen LIU Feng-jun XU Yi-fan 《应用心理学》 2025年第3期195-210,共16页
Across four studies,we explore the impact of solitude on consumers’reliance on feelings versus reasons in decision making,along with the underlying mechanism and boundary conditions.The results indicate that solitude... Across four studies,we explore the impact of solitude on consumers’reliance on feelings versus reasons in decision making,along with the underlying mechanism and boundary conditions.The results indicate that solitude individuals(vs.non-solitude)would prefer feeling-based strategy in decision-making,resulting in a higher intention of choosing the affectively superior option over the cognitively superior option(Study 1).Self-focus plays the underlying mechanism in the solitude effect(Study 2).Moreover,we also examine two boundary conditions:motivation(Study 3)and temporal orientation(Study 4),which indicates that involuntary motivation and future orientation can mitigate the solitude effect on affective processing.These findings provide insights into consumers’judgments of product attributes and selection of decision-making strategies according to their situations. 展开更多
关键词 SOLITUDE decision making SELF-FOCUS MOTIVATION temporal orientation
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Effect of cold rolling on aging precipitation and mechanical properties of magnesium-aluminum alloy 被引量:1
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作者 Feiya Liu Renlong Xin +1 位作者 Yiru Zhong Qing Liu 《Journal of Magnesium and Alloys》 2025年第6期2606-2617,共12页
Although magnesium-aluminum alloys,such as AZ80 and AZ91 have promising application potential in automotive,high-speed train and aerospace fields,their age-hardening response is generally not very appreciable.In this ... Although magnesium-aluminum alloys,such as AZ80 and AZ91 have promising application potential in automotive,high-speed train and aerospace fields,their age-hardening response is generally not very appreciable.In this work,the aging-hardening response of AZ80 alloy was effectively enhanced by applying cold-rolling deformation before conducting conventional aging treatment at 200°C.Compared to the directly aged sample,the yield strength of the pre-rolling and aged sample was increased by 35 MPa.Electron microscope examination confirmed that profuse{10¯11}and{10¯11}-{10¯12}twins,consisting of high density of dislocations and stacking faults,were generated by cold rolling.Blocky or ellipsoidal Mg_(17)Al_(12)precipitates formed at the twin boundaries(TBs)during subsequent aging treatment.Crystallographic analysis indicated that the precipitates at{10¯11}TBs always held an identical Potter OR with both the matrix and twin,while the precipitates at{10¯11}-{10¯12}TBs exhibited three different ORs:Burgers OR,Potter OR and P-S OR with either the matrix or the twin.Moreover,recrystallized grains were found inside{10¯11}-{10¯12}double twins after peak-aging at 200°C,implying that precipitation and recrystallization might occur concurrently along TBs at a relatively low temperature.It was speculated that the highly stored energy inside twins and the high elastic energy between the precipitates and twins were driving factors for the occurrence of recrystallization. 展开更多
关键词 Magnesium alloy Cold rolling Aging precipitation Twin boundary Orientation relationship
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Crystallographic micro-mechanism of faceted crack initiation in near-αtitanium alloy Ti6321 under room-temperature fatigue and dwell fatigue loadings 被引量:1
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作者 Wenyuan Zhang Qiaonan Shu +8 位作者 Jiangkun Fan Panpan Fan Xiangyi Xue Peng Jiang Minjie Lai Bing Tang Zhiqian Liao Hongchao Kou Jinshan Li 《Journal of Materials Science & Technology》 2025年第2期109-126,共18页
Crack initiation mechanism of dwell fatigue has always been a key problem in rationalizing the dwell effect,and it is not completely understood yet.This study conducted stress-controlled low-cycle fatigue and dwell fa... Crack initiation mechanism of dwell fatigue has always been a key problem in rationalizing the dwell effect,and it is not completely understood yet.This study conducted stress-controlled low-cycle fatigue and dwell fatigue tests on Ti-6Al-3Nb-2Zr-1Mo alloy with bimodal microstructure to reveal its microstructural characteristics and crack initiation mechanisms.The study demonstrated that the faceted primaryα nodules located near the specimen surface acted as crack initiation sites during both fatigue and dwell fatigue tests.Slip trace analysis revealed that faceted cracking occurred at(0001)basal plane with the maximum Schmid factor value through a special cracking mode referred to as(0001)twist boundary cracking.Innovative criteria of parameters C1 and C2 were proposed based on experimental observation and molecular dynamics simulations,which well identify candidates for(0001)twist boundary crack nucleation.It demonstrated that grain pairs combining a moderately high Schmid factor for basal slip and a well-orientated Burgers vector in the out-of-surface plane was the preferable location for surface(0001)twist-boundary crack initiation,and grain pairs combining a high Schmid factor for basal slip and a high normal stress on basal plane are perfect candidates for subsurface cracking.Based on this,phenomeno-logical models are proposed to explain the surface(0001)twist-boundary cracking mechanism from the perspective of surface extrusion-intrusion-induced micro-notches. 展开更多
关键词 Titanium alloy Dwell fatigue FACET Fatigue crack initiation Crystallographic 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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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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Prognostic value of quantitative flow ratio measured immediately after percutaneous coronary intervention for chronic total occlusion 被引量:1
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作者 Zheng QIAO Zhang-Yu LIN +10 位作者 Qian-Qian LIU Rui ZHANG Chang-Dong GUAN Sheng YUAN Tong-Qiang ZOU Xiao-Hui BIAN Li-Hua XIE Cheng-Gang ZHU Hao-Yu WANG Guo-Feng GAO Ke-Fei DOU 《Journal of Geriatric Cardiology》 2025年第4期433-442,共10页
BACKGROUND The clinical impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) in patients treated with PCI for chronic total occlusion (CTO) was still undetermined.METHODS All CTO vesse... BACKGROUND The clinical impact of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) in patients treated with PCI for chronic total occlusion (CTO) was still undetermined.METHODS All CTO vessels treated with successful anatomical PCI in patients from PANDA Ⅲ trial were retrospectively measured for postPCI QFR.The primary outcome was 2-year vessel-oriented composite endpoints (VOCEs,composite of target vessel-related cardiac death,target vessel-related myocardial infarction,and ischemia-driven target vessel revascularization).Receiver operator characteristic curve analysis was conducted to identify optimal cutoff value of post-PCI QFR for predicting the 2-year VOCEs,and all vessels were stratified by this optimal cutoff value.Cox proportional hazards models were employed to calculate the hazard ratio (HR) with 95% CI.RESULTS Among 428 CTO vessels treated with PCI,353 vessels (82.5%) were analyzable for post-PCI QFR.31 VOCEs (8.7%) occurred at 2 years.Mean value of post-PCI QFR was 0.92±0.13.Receiver operator characteristic curve analysis shown the optimal cutoff value of post-PCI QFR for predicting 2-year VOCEs was 0.91.The incidence of 2-year VOCEs in the vessel with post-PCI QFR<0.91 (n=91) was significantly higher compared with the vessels with post-PCI QFR≥0.91 (n=262)(22.0%vs.4.2%,HR=4.98,95%CI:2.32–10.70).CONCLUSIONS Higher post-PCI QFR values were associated with improved prognosis in the PCI practice for coronary CTO.Achieving functionally optimal PCI results (post-PCI QFR value≥0.91) tends to get better prognosis for patients with CTO lesions. 展开更多
关键词 chronic total occlusion cto Quantitative Flow Ratio Vessel Oriented Composite Endpoints Chronic Total Occlusion Prognostic Value panda iii Post Percutaneous Coronary Intervention
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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A graphene composite aerogel with a high thermal conductivity,compressibility and flexibility meets the requirements of phase-change materials for rigid-flexible material innovation
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作者 CUI Jia-ming CHEN Yi-xing +1 位作者 XU Wen-tao WANG Sheng 《新型炭材料(中英文)》 北大核心 2025年第5期1136-1153,共18页
Oriented graphene aerogels have limited applica-tions because the flexibility of their graphene sheets and mi-crostructure give them a low skeleton strength,insufficient compression resilience,and poor flexibility.We ... Oriented graphene aerogels have limited applica-tions because the flexibility of their graphene sheets and mi-crostructure give them a low skeleton strength,insufficient compression resilience,and poor flexibility.We report the preparation of novel aerogel materials with a much better per-formance.Using the driving force of graphene oxide(GO)self-assembly andπ-πinteractions,carbon nanotubes(CNTs)were attached to the GO sheets,and an oriented composite carbon skeleton was constructed using“hydro-plastic foam-ing”.The introduction of CNTs significantly increased the strength of the skeleton and gave the aerogel an excellent re-versible compressibility.The innovative use of cold pressing greatly improved the thermal conductivity and flexibility of the aerogel,providing new ideas for the development of high-performance aerogels.Tests show that the obtained graphene composite aerogel has a reversible compressive strain of over 90%and can withstand 500 compression cycles along the direc-tion of pore accumulation.It can endure more than 10000 bending cycles perpendicular to the direction of composite carbon layer stacking,and its in-plane thermal conductivity reaches 64.5 W·m^(-1)·K^(-1).When filled with phase change materials,the high porosity of the carbon skeleton enables the material to have a high phase change filling rate,and its phase change enthalpy is greater than 150 J/g.Thanks to the exceptional flexibility of the carbon skeleton,the macrostructure of phase change materials can be bent as needed to adapt to thermal management scenarios and conform to device shapes.This significantly enhances practical application compatibility,providing flexible support for temperature control and thermal management across diverse device forms. 展开更多
关键词 Oriented graphene aerogel GO CNT Hydro-plastic foaming Phase change material
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Redox-Active Monolayers on ITO Prepared by Post-Amidation and Direct Esterification and Their Spectroelectrochemical Characterization
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作者 Takamasa Sagara Sae Nakai +1 位作者 Ryusuke Yofu Shota Kojin 《电化学(中英文)》 北大核心 2025年第6期51-63,共13页
A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing.The necessity for its sophistication arises from the availability of multi-dimensional s... A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing.The necessity for its sophistication arises from the availability of multi-dimensional sensing signals.Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sen-sitivity and selectivity.This study aimed to elucidate the modification of an indium tin oxide(ITO)electrode with a viologen monolayer with an ordered orientation.Novel methods were developed to immobilize a viologen molecule bearing a car-boxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-car-bodiimide with N-hydroxy-succinimide(EDC/NHS).In the two methods of immobilization,one utilizes a two-step process to firstly form an aromatic siloxane base layer and subsequently attach the viologen derivative through an amide linkage by post-amidation.The other employs a direct ester linkage between the hydroxyl groups of the ITO surface and the car-boxyl group of the viologen derivative.The latter method was also applied to immobilize a ferrocenyl group at a very short distance from the ITO surface.Potential-modulated UV-visible transmission absorption spectral measurement techniques with oblique incidence of plane-polarized light were employed to determine the orientation of the longitudinal axis of the reduced form of the viologen.The frequency dependence data of the potential-modulated transmission absorption signals were utilized to analyze the electron transfer kinetics.The performance of the two viologen-modified electrodes was com-pared to that of an ITO modified by post-amidation to the most commonly used base layer prepared with 3-aminopropyl triethoxysilane. 展开更多
关键词 Redox-active monolayer ITO electrode Absorption spectroscopy Molecular orientation EDC/NHS
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