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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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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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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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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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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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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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Caffeine-enhanced Zn(0 0 2)texture-oriented growth for stable aqueous zinc-ion batteries
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作者 Zhihong Luo Tingting Xu +8 位作者 Liucheng Cao Qi Liu Degui Li Xiangqun Zhuge Laijun Liu Yibing Li Kun Luo Kai Qi Bao Yu Xia 《Journal of Energy Chemistry》 2025年第8期44-52,共9页
Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired... Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired by using green corrosion inhibitor for metals,we introduce caffeine,extracted from tea-leaf,as an additive to achieve stable AZIBs.Caffeine,with its N and O containing groups,strongly adsorbs on the Zn anode and Zn^(2+)ions.This featured adsorption induces the replacement of water molecules from electric double layer(EDL)and solvation shell,suppressing side-reactions such as corrosion and hydrogen evolution reaction(HER).Moreover,the selective adsorption and steric hindrance of caffeine promote Zn(002)-oriented deposition,resulting in uniform and compact zinc deposits at both low and high current density and areal capacity.Due to the significantly suppressed dendrites and corrosion,the Coulomb Efficiency(CE)reaches 99.24%after 800 cycles,and the Zn||MnO_(2)battery shows a specific capacity of 167.2 mAh g^(−1)with 81%capacity retention after 1000 cycles at 2 A g^(−1). 展开更多
关键词 Zn-ion battery Zn dendrites CAFFEINE Adsorption oriented growth
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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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How nestlings of Oriental Reed Warbler respond to adult alarm calls
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作者 Jiaojiao Wang Yongrui Feng +3 位作者 Laikun Ma Longwu Wang Canchao Yang Jianhua Hou 《Avian Research》 2025年第3期389-396,共8页
Avian alarm calls mediate defenses against brood parasites and predators. These calls facilitate communication among adults and alert nestlings to potential danger. While heterospecific call recognition has been exten... Avian alarm calls mediate defenses against brood parasites and predators. These calls facilitate communication among adults and alert nestlings to potential danger. While heterospecific call recognition has been extensively studied in adult birds, nestlings—lacking direct predation experience and heterospecific alarm exposure—represent an ideal system to investigate the response to interspecific warning cues. This study explored the recognition capabilities of 5–6-day-old nestlings in Oriental Reed Warbler (Acrocephalus orientalis), a common host of the Common Cuckoo (Cuculus canorus). We exposed the nestlings to playbacks of alarm calls directed at parasites and raptors from conspecific, Vinous-throated Parrotbill (Sinosuthora webbiana, sympatric species), Isabelline Shrike (Lanius isabellinus, allopatric species) and Common Tailorbird (Orthotomus sutorius, allopatric species) adults. Results indicated that there was no significant difference in the responses of nestlings to the alarm calls of conspecific and allopatric adults directed at cuckoos and sparrowhawks. In addition, interestingly, nestlings significantly reduced their begging in response to conspecific and unfamiliar allopatric Isabelline Shrike and Common Tailorbird alarm calls but exhibited a weak response to the sympatric Vinous-throated Parrotbill. Whether older warbler nestlings with more social experience exhibit stronger responses to the alarm calls of Vinous-throated Parrotbill adults requires further investigation. 展开更多
关键词 Alarm call Altricial nestling oriental Reed Warbler PARASITE PREDATOR
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Optimization of Talent Cultivation Strategies for Bioengineering Majors under Employment Orientation
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作者 Liqin YIN Yan WAN +2 位作者 Li HAO Yuanmou TANG Yanli XIA 《Agricultural Biotechnology》 2025年第5期77-80,85,共5页
The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed ... The rapid advancement of the bioeconomy imposes increasingly stringent demands on bioengineering education.Drawing on data from the 2025 Chinese Undergraduate Employment Report and related sources,this study revealed that while employment placement rates for bioengineering graduates remain stable,starting salaries exhibit limited growth and career trajectories lack clarity.These challenges originate from a curriculum lagging behind technological progress,inadequate practical training,and a mismatch between student competencies and industry expectations.To address these issues,this paper proposed a strategic framework grounded in"demand-driven design,industry-education integration,and competence-centered development".Key strategies include dynamic curriculum renewal,collaborative university-industry training,holistic competency development,and personalized student support,which collectively aim at enhancing graduates employment competitiveness and long-term professional sustainability. 展开更多
关键词 BIOENGINEERING Biology major Employment orientation Employment quality Talent cultivation Training strategy
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Syndiamesa fanduangularis sp.nov.(Diptera:Chironomidae),the first species of the genus from the Oriental Region
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作者 Yue Fu Jingru Shangguan Kaixia Yang 《Zoological Systematics》 2025年第4期348-354,共7页
The study describes a new species,Syndiamesa fanduangularis Fu,sp.nov.,representing the first record of the genus Syndiamesa from the Oriental Region.A detailed description of the new species is provided,including mor... The study describes a new species,Syndiamesa fanduangularis Fu,sp.nov.,representing the first record of the genus Syndiamesa from the Oriental Region.A detailed description of the new species is provided,including morphological data and illustrations.Molecular data(COI gene)were obtained and deposited in NCBI GenBank,providing a DNA barcode for species identification.The study also provides an updated key to adult males of the genus Syndiamesa globally. 展开更多
关键词 Diamesinae Syndiamesa new species oriental Region
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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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From“Orientalism”to the Eastern Beauty-the Progress of China Pavilions in the Expo
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作者 Wan Zewei 《China's Foreign Trade》 2025年第4期57-58,共2页
The China Pavilion has consistently been the primary vehicle for China's participation in World Expos over the years.From the first China Pavilion at the 1876 Philadelphia Expo to the 2025 China Pavilion at the on... The China Pavilion has consistently been the primary vehicle for China's participation in World Expos over the years.From the first China Pavilion at the 1876 Philadelphia Expo to the 2025 China Pavilion at the ongoing Osaka Expo,nearly 150 years have passed.During this span,the China Pavilion at the Expos. 展开更多
关键词 china pavilion world expos China Pavilion World Expo Eastern Beauty orientALISM
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Assessing the effect of plot size on species diversity in a mixed oriental beech forest
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作者 Narges Kardgar Ramin Rahmani +1 位作者 Habib Zare Somayeh Ghorbani 《Journal of Forestry Research》 2025年第1期209-222,共14页
Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fag... Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced. 展开更多
关键词 Species diversity oriental beech forest Sample plot size Richness EVENNESS
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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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Structure-oriented edge-preserving smoothing based on accurate estimation of orientation and edges 被引量:2
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作者 王珺 陈雨红 乔玉雷 《Applied Geophysics》 SCIE CSCD 2009年第4期367-376,395,共11页
In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orie... In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orientation and edge of the reflections. The information is usually estimated from seismic data with full frequency bandwidth. When the data has a very low signal to noise ratio (SNR), the noise usually reduces the estimation accuracy. For seismic data with extremely low SNR, the dominant frequency has higher SNR than other frequencies, so it can provide orientation and edge information more reliably than other frequencies. Orientation and edge are usually described in terms of apparent reflection dips and coherence differences, respectively. When frequency changes, both dip and coherence difference change more slowly than the seismogram itself. For this reason, dip and coherence estimated from dominant frequency data can approximately represent those of other frequency data. Ricker wavelet are widely used in seismic modeling. The Marr wavelet has the same shape as Ricker wavelets in both time and frequency domains, so the Marr wavelet transform is selected to divide seismic data into several frequency bands. Reflection apparent dip as well as the edge information can be obtained by scanning the dominant frequency data. This information can be used to selectively smooth the frequency bands (dominant, low, and high frequencies) separately by structure-oriented edge-preserving smoothing technology. The ultimate noise-suppressed seismic data is the combination of the smoothed frequency band data. Application to synthetic and real data shows the method can effectively reduce noise, preserve edges, improve trackable reflection continuity, and maintain useful information in seismic data. 展开更多
关键词 orientATION EDGE dominant frequency wavelet transform structure-oriented edge-preserving smoothing
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A Study on the Theme Orientation and Emotional Identity of Metaphorical Network Hot Words in Short Videos
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作者 ZHANG Wei-jie 《Journal of Literature and Art Studies》 2025年第4期310-316,共7页
In the wave of internet culture,short videos have become an indispensable medium for social communication.The metaphorical hot words contained within them serve as a unique linguistic phenomenon that leads topics and ... In the wave of internet culture,short videos have become an indispensable medium for social communication.The metaphorical hot words contained within them serve as a unique linguistic phenomenon that leads topics and focuses attention,greatly enriching the expressive layers and rhetorical charm of short videos,and significantly enhancing the video’s theme orientation and emotional identification.This research aims to explore the relationship between the use of metaphorical Internet buzzwords in short videos and the thematic and emotional orientation.The study adopts a combination of qualitative and quantitative methods,taking 10 videos with over 10,000 likes posted by a well-known blogger on Xiaohongshu in 2024 as the research object,transcribing the text,forming research corpora,and conducting multi-dimensional cognitive analysis on them.The study shows that about half of short videos contain metaphorical hot words.Different types of metaphorical hot words can trigger different emotional reactions from fans,especially humorous metaphorical hot words that can stimulate fans’emotional identification and resonance.In addition,in terms of fan participation,videos using metaphorical hot words tend to attract more fan attention than those that do not:these videos not only attract more fans to watch and like,but also trigger more comments and sharing behaviors.In summary,short videos cleverly use metaphors to create internet hot words,significantly enhancing the video’s thematic guidance and emotional resonance,manifested in creating popular topics,clarifying guiding themes,enhancing content attractiveness,and stimulating strong emotional identification,thereby promoting interactive behaviors such as likes and shares.These findings provide a reference for research in related fields such as metaphor,communication studies,and sociology. 展开更多
关键词 short videos internet hot words metaphor theme orientation emotional identity
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