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Temporal and Spatial Distribution of the Late Devonian (Famennian) Strata in the Northwestern Border of the Junggar Basin, Xinjiang, Northwestern China

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1413-1437页

作者： MA Xueping zhang Meiqiong ZONG Pu zhang yubo Lü Dan The Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The base of the Saerba Member （Mbr） of the Hongguleleng Formation （Fm.） probably lies in the Famennian Palmatolepis crepida Zone; the Longkou Mbr is probably a sedimentary wedge that thins out northwards; the Duguer Mbr has an approximate age from the upper part of the Pa. marginifera Zone or the Lower Pa. rugosa trachytera Zone through the top of the Pa. perlobata postera Zone; the Wulan Mbr has an age approximately corresponding to the whole Pa. gracilis expansa Zone. In the Bulongguoer section, the Lower Mbr of the Hongguleleng Fro. corresponds to Famennian Pa. crepida Zone through Pa. marginifera Zone; the Middle Mbr probably ranges from the Pa. r. trachytera Zone through the Pa. g. expansa Zone. The basal Namu Mbr of the Heishantou Fm. is probably the product during and after the Hangenberg Event in the upper part of the Siphonodellapraesulcata Zone, which is still within the Devonian. In this context, the underlying Chasi Mbr may approximately correspond to the lower part of the S. praesulcata Zone （before the Hangenberg Event）. Lateral distribution of strata indicates that the Upper Devonian in the Gennaren and Saerba areas each constitutes a structure of syncline, which differs from the previous recognition of a monocline structure.

关键词： Junggar Bulongguoer Hongguleleng Formation Heishantou Formation "Hebukehe"Formation Xinjiang

深冷轧制及时效处理过程中Cu-Fe合金的组织性能演变

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金属热处理 2024年第4期49卷 48-54页

作者：马启东张宇博岳世鹏陈佳乐李廷举大连理工大学材料科学与工程学院辽宁大连116024

利用SEM、XRD、TEM、力学性能及导电性能测试研究了Cu-5Fe合金在深冷轧制及时效过程中组织和性能的演变规律。结果表明,变形量为90%时,相比室温轧制,深冷轧制后合金的位错密度更高,Cu基体晶粒和Fe相的细化更显著。时效温度为500℃时,深... 详细信息

利用SEM、XRD、TEM、力学性能及导电性能测试研究了Cu-5Fe合金在深冷轧制及时效过程中组织和性能的演变规律。结果表明,变形量为90%时,相比室温轧制,深冷轧制后合金的位错密度更高,Cu基体晶粒和Fe相的细化更显著。时效温度为500℃时,深冷轧制试样中析出的纳米Fe相更加细小,数量更多,这是因为深冷轧制试样中更高的形变储能和位错密度更有效地促进了Fe相析出。经过90%变形量深冷轧制和500℃时效1 h后,Cu-5Fe合金的抗拉强度为551.5 MPa,导电率为69%IACS,综合性能优于室温轧制结合时效处理后的合金,这归因于深冷轧制试样再结晶后的晶粒仍小于室温轧制试样的,同时深冷轧制试样中更多纳米Fe相带来的析出强化效果更强,对合金的导电性影响也更小。

关键词： Cu-5Fe合金深冷轧制时效处理析出相

Effects of Strain Rate and Fiber Content on the Dynamic Mechanical Properties of Sisal Fiber Cement-Based Composites

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Journal of Renewable Materials 2023年第1期11卷 393-410页

作者： yubo zhang Ping Lei Lina Wang Jiqing Yang Facuty of Architecture and Civil Engineering Yunnan Agricultural UniversityKunming650000China

In this paper,a split Hopkinson pressure bar(SHPB)was used to investigate the dynamic impact mechanical behavior of sisal fiber-reinforced cement-based composites(SFRCCs),and the microscopic damage evolution of the composites was analyzed by scanning electron microscopy(SEM)and energy-dispersive X-ray spectrome-try(EDS).The results show that the addition of sisal fibers improves the impact resistance of cement-based composite *** with ordinary cement-based composites(OCCs),the SFRCCs demonstrate higher post-peak strength,ductility,and energy absorption capacity with higher fiber ***,the SFRCCs are strain rate sensitive materials,and their peak stress,ultimate strain,and energy integrals all increase with increasing strain *** the perspective of fracture failure characteristics,the failure of OCCs is dominated by the brittle failure of crystal *** contrast,the failure mode of the SFRCCs changes to microscale matrix cracks,multi-scale pull-out interface debonding of fibers(fine filaments and bundles),and mechanical *** research provides an experimental basis for the engineering application of high-performance and green cement-based composites.

关键词： Sisal fiber cement-based composites SHPB energy integration microstructure damage evolution law

Assessment of fatigue life of remanufactured impeller based on FEA

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Frontiers of Mechanical Engineering 2016年第3期11卷 219-226页

作者： Lei XU Huajun CAO Hailong LIU yubo zhang The State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400030 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China

Predicting the fatigue life of remanufactured centrifugal compressor impellers is a critical problem. In this paper, the S-N curve data were obtained by combining experimentation and theory deduction. The load spectrum was compiled by the rain-flow counting method based on the comprehensive consideration of the centrifugal force, residual stress, and aerodynamic loads in the repair region. A fatigue life simulation model was built, and fatigue life was analyzed based on the fatigue cumulative damage rule. Although incapable of providing a high-precision predic- tion, the simulation results were useful for the analysis of fatigue life impact factors and fatigue fracture areas. Results showed that the load amplitude greatly affected fatigue life, the impeller was protected from running at over-speed, and the predicted fatigue life was satisfied within the next service cycle safely at the rated speed.

关键词： remanufactured impeller fatigue life impeller failures finite element analysis (FEA)

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三亚市旺季智慧交通管理问题与对策研究

时代汽车 2024年第16期 190-192页

作者：韩丹孙铭泽张育博三亚理工职业学院海南三亚572000

文章针对三亚市在旅游旺季面临的道路交通拥堵问题进行研究,发现基础设施建设不完善,交通信号灯设置不合理以及市中心停车位短缺等导致交通拥堵问题。针对这些问题,文章提出了一系列应对措施,包括引入智能交通管理技术、建立实时交通信... 详细信息

文章针对三亚市在旅游旺季面临的道路交通拥堵问题进行研究,发现基础设施建设不完善,交通信号灯设置不合理以及市中心停车位短缺等导致交通拥堵问题。针对这些问题,文章提出了一系列应对措施,包括引入智能交通管理技术、建立实时交通信息发布平台、采取差异化的管理策略等。通过科学合理的交通管理政策和智能化的技术手段,可以有效缓解旅游旺季的交通拥堵问题,为三亚市旺季交通管理工作提供一些参考。

关键词：智慧交通交通管理拥堵管理

Highly efficient emission and high-CRI warm white light-emitting diodes from ligand-modified CsPbBr_(3) quantum dots

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Opto-Electronic Advances 2022年第1期5卷 35-48页

作者： Dongdong Yan Shuangyi Zhao yubo zhang Huaxin Wang Zhigang Zang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Chongqing UniversityChongqing 400044China Department of Physics Southern University of Science and TechnologyShenzhen 518055China

All-inorganic CsPbBr_(3) perovskite quantum dots(QDs)have received great attention in white light emission because of their outstanding ***,their practical application is hindered by poor ***,we propose a simple strategy to synthesize excellent stability and efficient emission of CsPbBr_(3) QDs by using 2-hexyldecanoic acid(DA)as a ligand to replace the regular oleic acid(OA)*** to the strong binding energy between DA ligand and QDs,the modified QDs not only show a high photoluminescence quantum yield(PLQY)of 96%but also exhibit high stability against ethanol and *** warm white light-emitting diodes(WLEDs)are constructed by combining lig-and modified CsPbBr_(3) QDs with red AgInZnS QDs on blue emitting InGaN chips,exhibiting a color rendering index of 93,a power efficiency of 64.8 lm/W,a CIE coordinate of(0.44,0.42)and correlated color temperature value of 3018 *** ad-dition,WLEDs based on ligand modified CsPbBr_(3) QDs also exhibit better thermal performance than that of WLEDs based on the regular CsPbBr_(3) *** combination of improved efficiency and better thermal stability with high color quality indicates that the modified CsPbBr_(3) QDs are ideal for WLEDs application.

关键词： CsPbBr_(3)quantum dots ligand modification stability efficiency white light-emitting diodes

汉语小句限定的词汇表征与语法系统:功能类型学视角

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北京科技大学学报（社会科学版） 2024年第4期40卷 63-74页

作者：张玉波杨炳钧董保华长江师范学院外国语学院重庆408100 中山大学国际翻译学院广州519080 重庆科技大学外国语学院重庆401331

以往有关汉语限定的研究多限于界定标准,鲜有对其具体词汇表征和语法系统的深入探讨。针对这一问题,文章首先依据系统功能类型学理论提出限定的类型学界定标准,然后依据该标准离析出汉语小句限定的具体的操作语,最后再根据这些操作语的... 详细信息

以往有关汉语限定的研究多限于界定标准,鲜有对其具体词汇表征和语法系统的深入探讨。针对这一问题,文章首先依据系统功能类型学理论提出限定的类型学界定标准,然后依据该标准离析出汉语小句限定的具体的操作语,最后再根据这些操作语的语义特征和聚合关系对其语法系统进行了描写。文章发现,汉语限定系统在指示类型上包含“体”、“情态”和“焦点”3个类型,其中“焦点”限定在精密度上可扩展为“事件”和“经历”2个类型,分别由“是”和“有”体现。文章中有关汉语小句限定的词汇语法表征可为更广阔的类型学比较和概括提供模式参照和数据参考。

关键词：功能类型学限定体情态是有

Enhancer and super-enhancer: Positive regulators in gene transcription

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Animal Models and Experimental Medicine 2018年第3期1卷 169-179页

作者： Yanling Peng yubo zhang Animal Functional Genomics Group Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural Sciences

Enhancer is a positive regulator for spatiotemporal development in eukaryotes. As a cluster, super-enhancer is closely related to cell identity- and fate-determined processes. Both of them function tightly depending on their targeted transcription factors, cofactors, and genes through distal genomic interactions. They have been recognized as critical components and played positive roles in transcriptional regulatory network or factory. Recent advances of next-generation sequencing have dramatically expanded our ability and knowledge to interrogate the molecular mechanism of enhancer and super-enhancer for transcription. Here, we review the history, importance, advances and challenges on enhancer and super-enhancer *** will benefit our understanding of their function mechanism for transcription underlying precise gene expression.

关键词： enhancer next-generation sequencing super-enhancer transcription regulation

Simulating Two-Phase Viscoelastic Flows Using Moving Finite Element Methods

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Communications in Computational Physics 2010年第2期7卷 333-349页

作者： yubo zhang Heyu Wang Tao Tang Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong Department of Mathematics Zhejiang UniversityHangzhouZhejiang 310027China

Phase-field models provide a way to model fluid interfaces as having finitethickness;the interface between two immiscible fluids is treated as a thin mixing layeracross which physical properties vary steeply but continuously. One of the main chal-lenges of this approach is in resolving the sharp gradients at the interface. In this paper,moving finite-element methods are used to simulate interfacial dynamics of two-phaseviscoelastic flows. The finite-element scheme can easily accommodates complex flowgeometry and the moving mesh strategy can cluster more grid points near the thin in-terfacial areas where the solutions have large gradients. A diffused monitor function isused to ensure high quality meshes near the interface. Several numerical experimentsare carried out to demonstrate the effectiveness of the moving mesh strategy.

关键词： Moving finite-element method two-phase flow viscoelastic flow non-Newtonian flow