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Friction stir based welding and processing technologies-processes,parameters,microstructures and applications:A review

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Journal of materials science & Technology 2018年第1期34卷 1-38页

作者： G.K.Padhy C.s.wu s.Gao mOE Key Lab for Liquid-solid structure Evolution and materials Processing Institute of Materials Joining Shandong University

Friction stir welding [FsW） has achieved remarkable success in the joining and processing of aluminium alloys and other softer structural alloys. Conventional FsW, however, has not been entirely successful in the joining, processing and manufacturing of different desired materials essential to meet the sophis- ticated green globe requirements. Through the efforts of improving the process and transferring the existing friction stir knowledge base to other advanced applications, several friction stir based daughter technologies have emerged over the timeline, A few among these technologies are well developed while others are under the process of emergence. Beginning with a broad classification of the scattered fric- tions stir based technologies into two categories, welding and processing, it appears now time to know, compile and review these to enable their rapid access for reference and academia. In this review article, the friction stir based technologies classified under the categol^J of welding are those applied for join- ing of materials while the remnant are labeled as friction stir processing （FsP） technologies. This review article presents an overview of four general aspects of both the developed and the developing friction stir based technologies, their associated process parameters, metallurgical features of their products and their feasibility and application to various materials. The lesser known and emerging technologies have been emphasized.

关键词： Friction stir welding Friction stir processing Friction stir scribe Friction stir riveting Friction stir channeling Friction stir forming Friction stir surfacing Friction stir additive manufacturing Friction stir cladding

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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science China Earth sciences 2025年第1期 270-296页

作者： song XIANG Jinshui HUANG Bingcheng wu school of Earth and space sciences University of Science and Technology of China CAs Center of Excellence in Comparative Planetary studies

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress between different tectonic modes ***, the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number, but decreases between other tectonic modes. Furthermore, we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate, with the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 mPa, which aligns with the strength of serpentinized mantle rock determined by experimental petrography. If the Archean mantle was 300°C warmer than it is today, then the Earth was in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

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Fictitious soil pile model for dynamic analysis of pipe piles under high-strain conditions

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Frontiers of structural and Civil Engineering 2023年第6期17卷 915-934页

作者： Yuan TU m.H.El NAGGAR Kuihua WANG Wenbing wu Juntao wu school of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China mOE Key Laboratory of soft soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Geotechnical Research Centre Department of Civil and Environmental EngineeringThe University of Western OntarioLondonONN6A 5B9Canada Engineering Research Center of Rock-soil Drilling Excavation and Protection Ministry of EducationChina University of GeosciencesWuhan430074China

A fictitious soil pile(FsP)model is developed to simulate the behavior of pipe piles with soil plugs undergoing high-strain dynamic impact *** developed model simulates the base soil with a fictitious hollow pile fully filled with a soil plug extending at a cone angle from the pile toe to the *** friction on the outside and inside of the pile walls is distinguished using different shaft models,and the propagation of stress waves in the base soil and soil plug is *** motions of the pile—soil system are solved by discretizing them into spring-mass model based on the finite difference *** of the predictions of the proposed model and conventional numerical models,as well as measurements for pipe piles in field tests subjected to impact loading,validate the accuracy of the proposed model.A parametric analysis is conducted to illustrate the influence of the model parameters on the pile dynamic ***,the effective length of the FsP is proposed to approximate the affected soil zone below the pipe pile toe,and some guidance is provided for the selection of the model parameters.

关键词： fictitious soil pile soil plug pipe piles high-strain dynamic analysis one-dimensional wave theory pile dynamics

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甲骨文词典编纂的创造性转化与创新性发展

河北学刊 2025年第1期45卷 74-81页

作者：洪飏吴昌昊辽宁师范大学文学院

甲骨文词典传统编纂体例存在受众群体有限、蕴含殷商社会文化成分较少、不利于展开专题研究等问题,再结合主题分类词典从古至今的发展应用情况,不难发现甲骨文领域中仅赵诚的《甲骨文简明词典——卜辞分类读本》是按主题分类编排的,但... 详细信息

甲骨文词典传统编纂体例存在受众群体有限、蕴含殷商社会文化成分较少、不利于展开专题研究等问题,再结合主题分类词典从古至今的发展应用情况,不难发现甲骨文领域中仅赵诚的《甲骨文简明词典——卜辞分类读本》是按主题分类编排的,但其分类标准并不纯粹。因此,急需编纂一部词汇学意义上的、按主题分类编排的甲骨文词典。新时代的甲骨文词典的编纂,需在习近平文化思想指引下,从编纂体例、编纂方法、成果产出、数据库建设等四个方面坚持守正创新,推动中华优秀传统文化创造性转化与创新性发展,采用人机协同的方法深度解析甲骨刻辞;应注重多成果产出,在编纂词典的同时,系联出主题分类词表、类纂和同义词词典;建立智能图文检索数据库,解决现有数据库不支持图片检索的难题,实现语言学、计算机技术和甲骨文研究的跨学科高度融合。

关键词：甲骨文词典主题分类数据库创新

Leader-follower: Human-centered intention-guided controller for novel superLimb with application to load-carrying scenarios

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science China Technological sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong LI Hongwei JING Kerui sUN Yuancheng LI sikai ZHAO Lele LI Haotian JU Ziqi WANG Rui wu Tianjiao ZHENG Jie ZHAO Yanhe ZHU The state Key Laboratory of Robotics and system Harbin Institute of Technology The Learning Algorithms and systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

supernumerary robotic arms(superLimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–superLimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of superLimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the superLimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between superLimb, humans, and the environment under human safety assurance. First, the human–superLimb dynamic system is modeled to achieve force interaction with the environment and wearer. second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–superLimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the superLimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and superLimb could well understand the wearer's intentions to switch different superLimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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The EsCRT protein CHmP5 escorts αβ T cells through positive selection

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Cellular & molecular Immunology 2018年第7期15卷 654-656页

作者： Glendon s wu Craig H Bassing Immunology Graduate Group Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA Divsion of Cancer Pathobiology Department of Pathology and Laboratory MedicineChildren’s Hospital of PhiladelphiaAbramson Family Cancer Research InstitutePerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA

αβ T lymphocytes are critical for host protection against pathogens and are notable for their recent use as immunotherapeutic agents for the treatment of human ***,their dysfunction is associated with a variety of disease states,including autoimmune and immunodeficient syndromes that frequently result from improper αβT cell development in the *** thymic egress,mature αβ T cells are activated when their surface T-cell receptor(TCR)engages peptide antigens displayed by major histocompatibility complex(mHC)proteins expressed on antigenpresenting *** the thymus,each developing αβ T cell(thymocyte)recombines its TCRβ and TCRαgenes in an attempt to assemble and express a unique functional αβ TCR。

关键词： lymphocytes autoimmune combine

Flip the switch: BTG2–PRmT1 protein complexes antagonize pre-B-cell proliferation to promote B-cell development

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Cellular & molecular Immunology 2018年第9期15卷 808-811页

作者： Glendon s wu Craig H Bassing Immunology Graduate Group Children’s Hospital of PhiladelphiaPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA Divsion of Cancer Pathobiology Department of Pathology and Laboratory MedicineChildren’s Hospital of PhiladelphiaAbramson Family Cancer Research InstitutePerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA

B lymphocytes are vital components of vertebrate adaptive immune ***,B-cell dysfunction can promote autoimmunity and immunodefi-ciency,and errors in development can cause B-lineage lymphoid malignancies.B-cell development requires RAG1/RAG2(RAG)endonuclease-mediated assembly of immunoglobulin(Ig)*** assembly of Ig heavy chain(IgH)genes in G1-phase pro-B cells produces IgH proteins that pair with VpreB/λ5 to form pre-B-cell receptor(pre-BCR)*** pro-B cells,pre-BCR signaling inhibits Rag1/Rag2 transcription,stabilizes Cyclin D3 to drive cellular proliferation and promotes differentiation of large pre-B cells.

关键词： lymphocytes lymphoid complexes

F）remature melt solidification during mold filling and its nfluence on the as-cast structure

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Frontiers of mechanical Engineering 2018年第1期13卷 53-65页

作者： m. wu m. AHmADEIN A. LUDWIG Chair for simulation and modeling of metallurgical Processes University of Leoben Leoben A-8700 Austria Christian-Doppler Laboratory for Advanced Process simulation ofsolidification and melting Department of Metallurgy University ofLeoben Leoben A-8700 Austria Production Engineering and mechanical Design Department Faculty ofEngineering Tanta University Tanta 31111 Egypt

Premature melt solidification is the solidifica- tion of a melt during mold filling. In this study, a numerical model is used to analyze the influence of the pouring process on the premature solidification. The numerical model considers three phases, namely, air, melt, and equiaxed crystals. The crystals are assumed to have originated from the heterogeneous nucleation in the undercooled melt resulting from the first contact of the melt with the cold mold during pouring. The transport of the crystals by the melt flow, in accordance with the so- called ＂big bang＂ theory, is considered. The crystals are assumed globular in morphology and capable of growing according to the local constitutional undercooling. These crystals can also be remelted by mixing with the super- heated melt. As the modeling results, the evolutionary trends of the number density of the crystals and the volume fraction of the solid crystals in the melt during pouring are presented. The calculated number density of the crystals and the volume fraction of the solid crystals in the melt at the end of pouring are used as the initial conditions for the subsequent solidification simulation of the evolution of the as-cast structure. A five-phase volume-average model for mixed columnar-equiaxed solidification is used for the solidification simulation. An improved agreement between the simulation and experimental results is achieved by considering the effect of premature melt solidification during mold filling. Finally, the influences of pouring parameters, namely, pouring temperature, initial mold temperature, and pouring rate, on the premature melt solidification are discussed.

关键词： premature solidification mold filling as-caststructure modeling

INTRAGRANULAR FERRITE FORmED IN AssOCIATION WITH INCLUsIONs IN A VANADIUm mICROALLOYED sTEEL

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Acta metallurgica sinica(English Letters) 2004年第6期17卷 785-789页

作者： K.m.wu m.Enomoto DepartmentofAppliedPhysics TheHubeiProvinceKeyLaboratoryofRefractionsandCeramies-Ministry-ProvinceJointly-ConstructedCultivationBaseforStateKeyLaboratoryWuhanUniversityofScienceandTechnologyWuhan430081China DepartmentofmaterialsscienceandEngineering IbarakiUniversityNakananusawaHitachi316-8511Japan

Intragranular ferrite was formed at inclusions in a vanadium microalloyed steel with excess amount of sulfur. The chemical composition of inclusions in the steel was analyzed by sEm-EDs. The inclusions were mainly composed of mns and aluminum oxides. The precipitation of mns at aluminum oxides might result in mn depletion, which, in turn, pro- motes the formation of intragranular ferrite. Optical and sEm observations and three- dimensional (3D) reconstruction demonstrated that intragranular ferrite was formed at inclusions. The morphology of intragranular ferrite changed with undercooling. At higher temperatures intragranular ferrite was nearly equiaxed whereas it was plate-like or lath-like at lower temperatures.

关键词： steels intragranular ferrite nucleation three-dimensional reconstruction