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Four New Compounds from Isodon Eriocalyx

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Chinese Chemical Letters 1997年第7期8卷 603-606页

作者： wang, J lin, Zw Shingu, t Sun, HD ACAD SINICA KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA KOBE GAKUIN UNIV FAC PHARMACEUT SCINISHI KUKOBEHYOGO 65121JAPAN

Four new diterpenoids named maoecrystal Q-t (1-4) were isolated from the dried leaves of Isodon eriocalyx. their sturctures were established by spectroscopic methods.

关键词： Four New Compounds from Isodon Eriocalyx OCH

Dynamic experiment and numerical simulation of frozen soil under confining pressure

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Acta Mechanica Sinica 2020年第6期36卷 1302-1318,I0004页

作者： w.R.tang Z.w.Zhu t.t.Fu Z.w.Zhou Z.H.Shanggua Applied Mechanics and Structural Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu610036China Northwest Institute of Eco-Environment and Resources State Key Laboratory of Frozen Soil EngineeringChinese Academy of SciencesLanzhou730000China

with the development of cold region engineering,it is crucial to study the mechanical properties of frozen *** practice,frozen soil is inevitably subject to impact loading,making the study of frozen soil under impact loading necessary for engineering in cold *** split–Hopkinson pressure bar(SHPB)is an important experimental means for obtaining the dynamic performance of *** this study,an SHPB experiment was conducted on frozen soil under confining *** frozen soil exhibited an evident strain rate effect and temperature effect under confining *** SHPB experiment on frozen soil under confining pressure was simulated numerically using LS-DYNA software and the Holmquist–Johnson–Cook(HJC)material model.A loading simulation with passive confining pressure and active confining pressure was completed by adding an aluminum sleeve and applying a constant *** simulation results obtained using the above methods were in good agreement with the experimental *** strength of the frozen soil under confining pressure was greater than that of the uniaxial impact,and there was an evident confining pressure ***,the confining pressure provided by passive confinement was larger than that provided by active *** passive confining pressure energy absorption efficiency was higher than for the active confining pressure due to the need to absorb more energy under the same damage *** frozen soil exhibited viscoplastic failure characteristics under confining pressure.

关键词： Frozen soil-Dynamic experiment Confining pressure Split-Hopkinson pressure bar Numerical simulation

职前教师学科教学知识的认知:困境、原因与改进策略

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教师教育学报 2025年第1期12卷 20-27页

作者：郭学君林林李娜宁波大学教师教育学院浙江宁波315211 上海财经大学国际文化交流学院上海200433 华中师范大学数学与统计学学院湖北武汉430079

职前教师学科教学知识的认知包括学科知识认知与教学实践两个层面。研究基于9位职前教师的27次反思报告,运用质性研究方法,通过分析职前教师对学科知识的诠释、重组、呈现,探究职前教师学科知识认知与教学实践之间的关系,并阐释职前教... 详细信息

职前教师学科教学知识的认知包括学科知识认知与教学实践两个层面。研究基于9位职前教师的27次反思报告,运用质性研究方法,通过分析职前教师对学科知识的诠释、重组、呈现,探究职前教师学科知识认知与教学实践之间的关系,并阐释职前教师学科教学知识的认知困境与原因。研究发现,如果职前教师未能意识到学科知识的独立性和专业性,则很难恰当地将学科知识融入教学实践,以致教学实践中存在学科知识欠缺的现象。故教师培养者应补充相关的学科知识,以帮助职前教师形成合理、整体、全面的学科教学知识;职前教师应深化、重组学科知识认知,调整审视教学内容的视角并在教学实践中恰当地呈现学科知识。

关键词：职前教师学科教学知识学科知识认知教学实践反思报告

Collaborative software design in an SOA environment

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Science in China(Series F) 2006年第6期49卷 821-842页

作者： w.t.tSAI Arizona State University Tempe AZ 85287-8809 USA

Based on the current Service-Oriented Architecture （SOA）, this paper proposes a new collaborative software design methodology in an SOA Environment： the Global Software Enterprise （GSE）. the current SOA is producer-centric, in which the service providers publish services that they produce and let the consumers to search avail- able services to compose their applications. GSE is build on top of Consumer-Centric SOA （CCSOA）, in which the application builders publish their application requirements for the service providers to follow when producing or customizing services to support the application. this new methodology reduces the workload and improves the application description capability of the service consumers. It also extends the capacity of design and code sharing, and thus further improves the software productivity. this paper presents the concepts, architecture, enabling techniques, and illustrative examples of collaborative software design in GSE.

关键词： SOA,Global Software Enterprise (GSE) CCSOA software productivity

Evolution and implementation of the Digital Earth vision,technology and society

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International Journal of Digital Earth 2008年第1期1卷 4-16,I0001页

作者： t.w.Foresman International Center for Remote Sensing Education P.O.Box 18285 BaltimoreMD 21227

Digital Earth’s framework can be traced to evolutionary threads with historic foundations that fostered the fertile conceptual and technological *** threads incorporate writings,such as those of the visionary engineering-genius,Buckminster Fuller,in conjunction with an array of space age develop-ments in computers,internet and communications,satellites,and *** 1998,when Vice President Al Gore articulated the Digital Earth Vision,he portrayed the vision based upon myriad technology factors for the intellectual foundation and sparked a worldwide phenomenon that fortuitously included the Chinese leadership’s recognition and *** Beijing Declaration is recognised for its role promulgating the International Digital Earth Symposium series to promote better understanding of the impacts of Digital Earth technology and applications on behalf of all *** of industrial,academic,and government organisations have advanced the technological components necessary for implementing the Digital Earth Vision at a prodigious *** leaders,such as Google,have accelerated the influence of large segments of society towards components of the Digital Earth ***,challenges still remain regarding requisite collaboration on international stan-dards for metadata,interoperability,and data formats for space and time that will affect Digital Earth implementation *** requirements for the model Digital Earth geobrowser remain to be fully *** current paper presents an overview of the historical components,the key players on the international scene,the catalytic technological advances,and the societal response to the growth of the Digital Earth community.

关键词： digital earth 3D geobrowser GIS,remote sensing sustainability

Impact of E×B flow shear stabilization on particle confinement and density peaking at JEt

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Plasma Science and technology 2020年第6期22卷 60-73页

作者： w BUANGAM J GARCIA t ONJUN JEt Contributors School of Manufacturing Systems and Mechanical Engineering Sirindhorn International Institute of TechnologyThammasat UniversityPathumthani 12120Thailand CEA IRFMSaint-Paul-lez-Durance F-13108France thailand Institute of Nuclear technology Chatuchak 10900Thailand 不详

the impact of the E×B flow shear stabilization on particle transport and density peaking at JEt is analyzed in the framework of integrated modelling with the CRONOS *** that purpose,plasmas from a power scan which show a significant increasing of density peaking with the injected neutral beam injection power have been used as a modeling *** means of simulations with the quasilinear model GLF23 for the heat and particle transport,a strong link between the particle confinement and E×B flow shear stabilization is *** is particularly important close to the pedestal region where the particle pinch direction becomes strongly inward for high E×B flow shear *** impact introduces some non-negligible deviation from the well-known collisonality dependence of the density peaking,whose general trend has been also obtained in the framework of this modelling by performing pedestal density scans.

关键词： particle confinement density peaking flow shear transport

Grain size and temperature effect on the tensile behavior and deformation mechanisms of non-equiatomic Fe(41)Mn(25)Ni(24)Co8Cr2high entropy alloy

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Journal of Materials Science & technology 2020年第7期42卷 190-202页

作者： H.t.Jeong w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul121-791Republic of Korea

the effect of the grain size on the tensile properties and deformation mechanisms of a nonequiatomic Fe(41)Mn(25)Ni(24)Co8 Cr2 high-entropy alloy was studied in the temperature range between 298 and 1173 K by preparing the samples with three different grain sizes through severe plastic deformation and subsequent annealing:ultrafine(sub)grain size(≤0.5μm),8.1μm and 590.2μ*** the temperature between 298 and773 K,the material with the large grain size of 590.2μm exhibited the largest tensile ductility(57%-82%)due to its high strain hardening associated with mechanical twinning,but it exhibited the lowest strength due to its large grain *** material with the ultrafine(sub)grain size exhibited the lowest tensile ductility(3%-7%)due to a greatly reduced strain hardening ability after severe plastic deformation,but it exhibited the highest strength due to the dislocation strengthening and grain refinement *** tensile testing at temperatures above 973 K,recrystallization occurred in the material with the ultrafine(sub)grains during the sample heating and holding stage,leading to the formation of fine and equiaxed grains with the sizes of 6.8-13.5μ*** deformation behavior of the Fe(41)Mn(25)Ni(24)Co8 Cr2 with different grain sizes in the high temperature range between 973 and 1173 K,where pseudosteady-state flow was attained in the stress-strain curves,could be explained by considering the simultaneous contribution of grain boundary sliding and dislocation-climb creep to total plastic *** activation energies for plastic flow for the materials with different grain sizes were similar as^199 kJ/*** predicting the deformation mechanism,it was important to consider the change in grain size by rapid grain growth or recrystallization during the sample heating and holding stage because grain boundary sliding is a grain-size-dependent deformation *** sample with the ultrafine(sub)grains exhibited the large tensile elongations of 30%-85%due to it

关键词： High entropy alloys Grain size High temperature deformation mechanism tensile behavior Grain boundary sliding

Effects of grain size and Al addition on the activation volume and strain-rate sensitivity of CoCrFeMnNi high-entropy alloy

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Journal of Materials Science & technology 2023年第12期143卷 242-252页

作者： H.t.Jeong w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul121-791Republic of Korea

the activation volume(V∗)and strain-rate sensitivity exponent(m)of CoCrFeMnNi and Al_(0.5)CoCrFeMnNi high entropy alloys(HEAs)with various grain sizes(ranging between 2.4 and 356μm)were measured at different strain rates and strain levels at room *** the strain rate decreased,the plastic strain decreased,and the grain size increased,V∗*** enhanced solid-solution strengthening by addition of aluminum decreased V∗.the Hassen plot was modified to capture the grain-size depen-dence of V∗by considering the grain-size dependence of the dislocation *** the plastic strain increased,the strain rate decreased,and the grain size decreased,m *** behavior of m could be quantitatively predicted by using equations derived for the grain-size-dependent V∗and flow *** difference in the grain-size dependence of m between conventional face centered cubic(FCC)metals and FCC HEAs over the nanograin size range could not be explained in terms of a relatively large Hall-Petch slope of the FCC HEAs compared with that of the FCC conventional metals,but was explainable in terms of a substantially higher probability of activation of grain-boundary diffusion-controlled grain-boundary-sliding mechanism at nanograin sizes in the FCC conventional metals than in the FCC HEAs.

关键词： Grain size High entropy alloys Activation volume Strain-rate sensitivity Solid solution

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毛囊类器官研究:现状、问题与前景

中国组织工程研究 2025年第31期29卷 6733-6742页

作者：王钊龚琳朴永君大连医科大学附属第一医院皮肤科辽宁省大连市116000

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内... 详细信息

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内。毛囊类器官研究使毛囊再生成为可能,但构建方法亦无统一定论,仍面临诸多挑战。目的:综述目前毛囊类器官的研究进展,总结毛囊类器官培养方法及表征,阐述应用前景,为后续研究提供可靠依据,以期促进其在组织工程及脱发治疗的临床转化。方法:应用计算机在中国知网(CNKI)及PubMed数据库中,以“毛囊再生,毛发再生,类器官”为中文检索词,“hair growth,hair loss,hair regeneration,hair follicle,dermal papilla cell,organoid”为英文检索词进行检索,查阅国内外关于毛囊类器官的相关文献,共纳入文献67篇进行后续分析。结果与结论:①不同来源的毛乳头细胞与角质形成细胞可在体外构建毛囊类器官,以获得鼠源、人-鼠嵌合及人源毛囊类器官,并成功用于啮齿动物移植模型;②多种重编程方法如电刺激、添加重组蛋白、解离细胞基因过表达等可用于促进毛囊类器官毛胚形成及毛钉伸长,同时,多种3D打印技术的应用已实现大小可控毛囊类器官的批量生产,极大提高了生产效率;③在解离细胞共培养体系中加入黑素细胞时,或可破译新生毛囊的色素缺失难题,而加入人脐静脉血管内皮细胞时,细胞聚集体内的新生血管可改善营养供给,减少中心部位坏死;④随着工程化类毛囊技术逐渐趋于成熟,患者自体细胞构建的毛囊类器官或可用于严重脱发的个体化医疗。

关键词：脱发毛囊再生毛乳头细胞毛囊类器官上皮-间充质交互作用 3D培养类器官组织工程工程化类器官

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