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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei Chen Yang Jiang Xiaofei Guo han dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

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文化的生死问题探源

河北学刊 2025年第1期45卷 91-97页

作者：韩东屏华中科技大学哲学学院

文化的生死作为既成事实,只能是指群体文化的生死。学术界专门研究过文化生死的学者,有斯宾格勒和汤因比。但这二人无论是对文化之生死的指认,还是对文化生死之因的解释,都存在谬误,不能成立。文化作为人类创造力的果实,从生物性意义的... 详细信息

文化的生死作为既成事实,只能是指群体文化的生死。学术界专门研究过文化生死的学者,有斯宾格勒和汤因比。但这二人无论是对文化之生死的指认,还是对文化生死之因的解释,都存在谬误,不能成立。文化作为人类创造力的果实,从生物性意义的现代人类算起,其生即起点是晚期智人的原始群文化,其后相继演变为氏族文化和国家文化,而其死即终点则是文化的主人不复存在之时。其生的成因是人为了满足自身需求所进行的创造,死的原因是群体文化的创造者和使用者被外部力量消灭或打散。

关键词：文化生死群体文化民族文化

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群体践行之知的互动-整合模型

科学技术哲学研究 2025年第1期42卷 23-30页

作者：方玄子韩东晖中国人民大学哲学院北京100872 中国延安干部学院陕西延安716000

当代认识论中关于践行之知(knowing-how)概念的讨论一直都是错综复杂的难题。随着社会知识论和社会存在论的不断繁荣,知识的社会性维度和群体知识日益成为学术界探究的热点。群体作为由个体组成的行动者,是否拥有以及如何运用践行之知... 详细信息

当代认识论中关于践行之知(knowing-how)概念的讨论一直都是错综复杂的难题。随着社会知识论和社会存在论的不断繁荣,知识的社会性维度和群体知识日益成为学术界探究的热点。群体作为由个体组成的行动者,是否拥有以及如何运用践行之知也得到一定程度的研究。争议的焦点之一在于群体能否成为行动和知识的主体,如何平衡关于群体行动的还原论和反还原论立场。我们在相关讨论的基础上,力图构建一个互动-整合理论模型,以解释群体如何掌握和运用践行之知,旨在阐明群体如何通过个体间的协调、社会互动、认知整合以及文化传承来形成复杂且独特的实践能力。这一理论模型不仅旨在调和上述争议,更期望为理解群体知识的本质提供新的视角。

关键词：群体践行之知践行之知社会知识论社会存在论集体意向性

Is intraperitoneal isoperistaltic side-to-side anastomosis a safe surgical procedure in radical colon cancer surgery

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 133-143页

作者： Bin Wu Jing-Tao Zhu He-Xin Lin Yu-Hua Dai Tian-Sheng Lin An-Le Huang Yi-Nan Chen Yong-Wen Li Hai-Bin Wang Yi-Fu Chen dong-han Chen Huang-Dao Yu Jun You Qing-Qi Hong Department of Gastrointestinal Oncology Surgery The First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361003Fujian ProvinceChina

BACKGROUND Colorectal cancer,one of the most common malignancies,is primarily treated through *** the widespread use of laparoscopy,gastrointestinal reconstruction remains a key area of *** choice between intraperitoneal anastomosis(IA)and extraperitoneal anastomosis(EA)remains a subject of considerable *** study uses intraperitoneal isoperistaltic side-to-side anastomosis(IISSA)with hand-sewn closure of the common opening to evaluate its safety and short-term *** is hypothesized that this technique may offer better short-term outcomes than *** To investigate the safety and short-term outcomes of IISSA with hand-sewn closure of the common opening compared to *** Patients who underwent laparoscopic radical colon cancer surgery between January 2018 and June 2022 at the First Affiliated Hospital of Xiamen University were retrospectively ***,postoperative,and pathological features of the IA and EA groups were observed before and after propensity score *** with right-sided and left-sided colon cancer were separated,each further divided into IA and EA groups(R-IA vs R-EA for right-sided,L-IA vs L-EA for left-sided),for stratified analysis of the aforementioned *** After propensity score matching,63 pairs were matched in each *** surgical characteristics,the IA group exhibited less blood loss and shorter incisions than the EA *** postoperative recovery,the IA group showed earlier recovery of gastrointestinal ***,the IA group had greater lymph node *** to the R-EA group,the R-IA group experienced reduced blood loss,shorter assisted incisions,earlier recovery of gastrointestinal functions and greater lymph node *** compared to the L-EA group,the L-IA group demonstrated earlier postoperative anal exhaust and defecation,along with a reduced length of *** postoperative complications,no statistically signific

关键词： Colon cancer Laparoscopic surgery Intraperitoneal anastomosis Extraperitoneal anastomosis Isoperistaltic sideto-side anastomosis hand-sewn

深厚软弱覆盖层高承压水地质条件下锚碇受力变形及稳定性研究

维普期刊数据库评论

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公路 2025年第02期70卷 175-182页

作者：姚宇周彦锋管维东唐政韩冬冬同济大学桥梁工程系华设设计集团股份有限公司中交公路长大桥建设国家工程研究中心有限公司

张靖皋长江大桥北航道桥是主跨为1 208 m、缆跨布置为530 m+1 208 m+530 m的双塔单跨吊悬索桥。该桥南锚碇处软弱覆盖层以粉质黏土为主，厚度为43.8～50.5 m,粉质黏土层以下砂层均为承压含水层，承压水水头埋深在地面以下1.6～3.25 m,... 详细信息

张靖皋长江大桥北航道桥是主跨为1 208 m、缆跨布置为530 m+1 208 m+530 m的双塔单跨吊悬索桥。该桥南锚碇处软弱覆盖层以粉质黏土为主，厚度为43.8～50.5 m,粉质黏土层以下砂层均为承压含水层，承压水水头埋深在地面以下1.6～3.25 m,承压水水头高。南锚碇基础采用外径为90 m、墙厚为1.5 m的复合地基圆形地下连续墙基础，为满足基础底部地基承载力、抗渗性能、摩擦系数等的要求，基底以下28 m厚(局部加厚至30.5 m)进行地基加固处理。结合项目工程建设条件，对南锚碇基坑开挖地连墙支护结构受力变形、抗渗性能、抗滑和抗倾覆、地基承载力和锚点位移进行验算，结果均满足规范要求。所采用的锚碇基础及地基加固设计方案，可为类似深厚软弱覆盖层高承压水地质条件下桥梁锚碇结构类型和基础持力层的选择提供参考。

关键词：桥梁工程张靖皋长江大桥北航道桥软弱覆盖层圆形地下连续墙复合地基深层地基加固地基承载力

Pitch link loads reduction of variable speed rotors by variable tuning frequency fluidlastic isolators

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Chinese Journal of Aeronautics 2015年第5期28卷 1408-1415页

作者： han dong National Key Laboratory of Science and Technology on Rotorcraft Aeronautics College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics

To reduce the pitch link loads of variable speed rotors, variable tuning frequency fluid- lastic isolators are proposed. This isolator utilizes the variation of centrifugal force due to the change of rotor speed to change the tuning port area ratio, which can change the tuning frequency of the isolator. A rotor model including the model of fluidlastic isolator is coupled with a fuselage model to predict the steady responses of the rotor system in forward flight. The aeroelastic analyses indicate that distinct performance improvement in pitch link load control can be achieved by the utilization of variable frequency isolators compared with the constant tuning frequency isolators. The 4/rev （per revolution） pitch link load is observed to be reduced by 87.6% compared with the increase of 56.3% by the constant frequency isolator, when the rotor speed is reduced by 16.7%. The isolation ability at different rotor speeds in different flight states is investigated. To achieve overall load reduction within the whole range of rotor speed, the strategy of the variation of tuning frequency is adjusted. The results indicate that the 4/rev pitch link load within the whole rotor speed range is decreased.

关键词： Fluidlastic isolator Loads Pitch link Reduction Rotor Variable frequency Variable speed

基于中空十四面体杆板混杂点阵结构的声学性能与力学性能研究

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中国科学:技术科学 2025年第2期55卷 261-269页

作者：李凌博杨帆李鹏飞韩东同济大学航空航天与力学学院上海200092 同济大学民航航空器结构智能辅助适航重点实验室上海100191 大连理工大学工业装备结构分析、优化与CAE软件国家重点实验室大连116024 上海飞行器力学与控制研究院上海200092

点阵结构因其轻质高强、高设计自由度,在承载、缓冲吸能和减振降噪方面具有广阔的应用前景.然而,传统类型的点阵结构很难同时具备较好的吸声性能和较强的承载性能.本文提出了一种新型三维轻质多功能结构——中空十四面体杆板(HTTP)混杂... 详细信息

点阵结构因其轻质高强、高设计自由度,在承载、缓冲吸能和减振降噪方面具有广阔的应用前景.然而,传统类型的点阵结构很难同时具备较好的吸声性能和较强的承载性能.本文提出了一种新型三维轻质多功能结构——中空十四面体杆板(HTTP)混杂点阵结构,利用增材制造技术制备了实验试样.基于传递矩阵法建立了多级联类亥姆霍兹共振腔的理论模型,并进行了有限元数值模拟和阻抗管实验,实验、理论和数值结果具有良好的一致性.结果表明,板厚0.5 mm的HTTP在第二吸声峰处实现阻抗匹配,同时具有较高的平均吸声系数和宽带半吸收.通过数值均匀化方法和准静态压缩实验研究了HTTP的力学性能,结果表明,HTTP在板厚0.3 mm处实现了弹性各向同性.在压缩过程中杆件与板件相互作用形成了更加稳定的渐进弯曲变形模式,使其在塑性阶段表现出较高且稳定的平台应力.本文提出的HTTP多功能混合点阵结构可同时实现高吸声和强力学性能,为多功能轻质结构的设计提供了一种新的范式.

关键词：混杂点阵结构吸声性能力学性能多功能增材制造

Hover performance of helicopter main and tail rotors with swirl velocities

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航空动力学报 2021年第1期36卷 119-129页

作者： YANG Kelong han dong National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

It is important to quickly predict the hover performance of main and tail rotors with sufficient precision for helicopter design. To investigate the effects of swirl velocities on the hover performance of main and tail rotors, and give a better prediction for the hover performance, a flight performance model was derived and a swirl velocity model was coupled into it. The test data of the UH-60 A helicopter were used for validation. When the blade loading coefficient of the main rotor was higher than 0.05, the effects of the swirl velocities on the main rotor power became significant. The swirl velocities increased the profile torque of the main rotor. The increased torque required the tail rotor to produce more thrust with more power consumption. At a higher blade loading coefficient of the main rotor of 0.12, the swirl velocities increased the main rotor power, tail rotor power and total power by 3.80%, 5.24% and 5.08%, respectively. The profile power increase of the main rotor caused by the profile swirl velocity was less than that of the induced swirl velocity, but the power increase was higher at high rotor blade loadings. Considering the swirl velocities in the main rotor can improve the prediction precision of the hover performance, especially at high blade loadings.

关键词： swirl velocities hover performance main and tail rotors blade loading rotor power

High performance steels:Initiative and practice

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Science China(Technological Sciences) 2012年第7期55卷 1774-1790页

作者： dong han Central Iron&Steel Research Institute Beijing 100081China

In order to meet the progressive requirement for the performance improvement of steel,the author proposed a novel microstructure featured with multi-phase,meta-stable and multi-scale(so-called as M 3).And then,the new technologies could be developed to process three prototype steels with high performance:the third generation high strength low alloy(HSLA) steels with improved toughness and/or ductility(AKV(40℃)≥200 J and/or A≥20% when Rp0.2 in 800-1000 MPa),the third generation advanced high strength steels(AHSS)(Rm×A≥30 GPa% when Rm from 1000 MPa to 1500 MPa) for automobiles with improved ductility and low cost,and heat resistant martensitic steels with improved creep strength(10000650≥90 MPa).It can be expected that the new technology developed will remarkably improve the safety and reliability of steel products in service for infrastructures,automobiles and fossil power station in the future.

关键词： high performance steels M 3 microstructure evolution phenomenon and mechanisms processing

抗阻运动激活Piezo1/AMPK/PGC-1α缓解小鼠废用性骨骼肌萎缩

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中国生物化学与分子生物学报 2025年第1期41卷 136-146页

作者：韩东生梁擎宇石晓峰山西大学体育学院太原030006 山西医科大学第二医院设备处太原030001

本研究旨在探究抗阻运动能否通过激活骨骼肌Piezo1/AMPK/PGC-1α信号通路,改善线粒体功能和促进肌生成,从而有效缓解废用性骨骼肌萎缩。采用8周龄雄性C57BL/6J小鼠,通过后肢石膏固定模拟废用性肌肉萎缩,并分为对照组、废用性肌萎缩组、... 详细信息

本研究旨在探究抗阻运动能否通过激活骨骼肌Piezo1/AMPK/PGC-1α信号通路,改善线粒体功能和促进肌生成,从而有效缓解废用性骨骼肌萎缩。采用8周龄雄性C57BL/6J小鼠,通过后肢石膏固定模拟废用性肌肉萎缩,并分为对照组、废用性肌萎缩组、废用性肌萎缩+抗阻运动组和废用性肌萎缩+抗阻运动+Piezo1抑制剂组。抗阻运动组进行为期8周的抗阻训练。通过Western印迹、免疫荧光染色、线粒体质量和功能检测等方法,评估骨骼肌质量、功能、线粒体状态和肌生成情况。抗阻运动使废用性肌萎缩小鼠的骨骼肌横截面积增加23%(P<0.01),骨骼肌相对质量增加11%(P<0.01)。抗阻运动使小鼠最长跑步距离平均增加206 m(P<0.01),最大承载力平均增加36.7g(P<0.01),平衡木爬行时间平均缩短1.5 s(P<0.01),同时上调了Piezo1、AMPK、PGC-1α的蛋白质表达水平(P<0.01)。此外,抗阻运动还增加了小鼠骨骼肌中MMP、TFAM、COXⅠ、CS、ATPB、ATPase、ATP、p-mTOR/mTOR、p-P70S6K/P70S6K、Pax7和MyoD的活性或蛋白质表达的水平(P<0.05,P<0.01)。而抑制Piezo1则降低了上述酶活性和蛋白质的表达水平(P<0.05,P<0.01)。抗阻运动通过激活Piezo1/AMPK/PGC-1α通路,提高了骨骼肌线粒体质量和功能,促进了蛋白质合成和肌生成,有效缓解了废用性骨骼肌萎缩。

关键词：抗阻运动压电式机械敏感离子通道组件1 废用性骨骼肌萎缩肌生成