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Chinese Journal of Aeronautics 2023年第4期36卷 556-564页

作者： Donghui GUO Feifei ZHOU baosheng xu Yiguang WANG You WANG Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Department of Materials Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

Poor fracture toughness leads to premature failure of La_(2)(Zr_(0.75)Ce_(0.25))_(2)O_(7)(LCZ)ther-mal barrier coatings in an elevated temperature service environment.A novel coating material,namely(La_(0.2)Nd_(0.2)Sm_(0.2)Gd_(0.2)Yb_(0.2))_(2)(Zr_(0.75)Ce_(0.25))_(2)O_(7)(LNSGY)based on the high-entropy con-cept,was successfully fabricated by solid-state *** microstructure of LCZ and LNSGY was investigated by X-Ray Diffraction(XRD),Raman Spectrometer(RS),Transmission Electronic Microscopy(TEM)and Scanning Electron Microscopy(SEM).The fracture toughness of the LCZ and LNSGY ceramics was *** LNSGY has excellent high-temperature phase stability,and the grain size of LNSGY ceramic is smaller than that of LCZ ceramic at an elevated temper-ature due to the sluggish diffusion *** with LCZ(fracture toughness is(1.4±0.1)MPa·m^(1/2)),the fracture toughness of LNSGY is significantly enhanced(fracture toughness is(2.0±0.3)MPa·m^(1/2)).Therefore,the LNSGY can be a promising advanced thermal barrier coat-ing material in the future.

关键词： Fracture toughness High-entropy ceramics High-temperature phase sta-bility Rare-earth zirconate Thermal barrier coatings

High-entropy rare-earth zirconate ceramics with low thermal conductivity for advanced thermal-barrier coatings

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Journal of Advanced Ceramics 2022年第6期11卷 961-973页

作者： Debao LIU Baolu SHI Liyan GENG Yiguang WANG baosheng xu Yanfei CHEN Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Shanghai Space Propulsion Technology Research Institute Shanghai 201109China

The high-entropy rare-earth zirconate((La_(0.2)Nd_(0.2)Sm_(0.2)Gd_(0.2)Yb_(0.2))_(2)Zr_(2)O_(7),5RE_(2)Zr_(2)O_(7)HEREZs)ceramics were successfully prepared by a new high-speed positive grinding strategy combined with solid-state reaction *** microstructure,crystal structure,phase composition,and thermophysical and mechanical properties of the samples were systematically investigated through various *** indicate that the samples have a single-phase defect fluorite-type crystal structure with excellent high-temperature thermal *** as-prepared samples also demonstrate low thermal conductivity(0.9–1.72 W·m^(−1)·K^(−1)at 273–1273 K)and high coefficient of thermal expansion(CTE,10.9×10^(−6)K^(−1)at 1273 K),as well as outstanding mechanical properties including large Young’s modulus(E=186–257 GPa)and high fracture toughness(KIC).Furthermore,the formation possibility of the as-prepared samples was verified through the first-principles calculations,which suggested the feasibility to form the 5RE_(2)Zr_(2)O_(7)HE-REZs in the thermodynamic ***,in view of the excellent multifunctional properties exhibited by the as-prepared 5RE_(2)Zr_(2)O_(7)HE-REZs,they have great potential applications in next-generation thermal-barrier coatings(TBCs).

关键词： high-entropy rare-earth zirconates(HE-REZs) first-principles calculations thermal conductivity thermal stability Young’s modulus thermal-barrier coatings(TBCs)

An improved time integration scheme based on uniform cubic B-splines and its application in structural dynamics

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Applied Mathematics and Mechanics(English Edition) 2017年第6期38卷 889-908页

作者： Weibin WEN Hongshuai LEI Kai WEI baosheng xu Shengyu DUAN Daining FANG College of Engineering Peking UniversityBeijing 100871China Beijing Institute of Technology Beijing 100081China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body School of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Key Laboratory of Applied Mechanics Department of Engineering MechanicsSchool of Aerospace EngineeringTsinghua UniversityBeijing 100084China

A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom （SDOF） system, and then is generalized for a multiple-degree of freedom （MDOF） system. Stability analysis shows that, with an adjustable algorithmic parameter, the proposed method can achieve both conditional and unconditional stabilities. Validity of the method is shown with four numerical simulations. Comparison between the proposed method and other methods shows that the proposed method possesses high computation accuracy and desirable computation efficiency.

关键词： dynamical system time integration~ stability dynamic response B-spline

Lightweight quasi-layered elastic fibrous porous ceramics with high compressive stress and low thermal conductivity

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Journal of Materials Science & Technology 2023年第12期143卷 207-215页

作者： Ning Zhou baosheng xu Zhiliang Zhou Lijie Qu Yiguang Wang Wenbo Han Daining Fang National Key Laboratory of Science and Technology for National Defense on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Fibrous porous ceramics are attractive for use as thermal insulation ***,the intrinsic brit-tleness of rigid materials has remained challenging and severely restricts their ***,we demonstrated a facile method for fabricating elastic fibrous porous ceramics(EFPCs)with high com-pressive strength and low thermal conductivity through ordinary press filtration and subsequent heat *** quasi-layered structure and the well-bonded bridging fibers between layers are the key points for the elasticity of *** advanced EFPCs exhibited low density(∼0.126 g cm^(−3)),high com-pressive stress(∼0.356 MPa),and low thermal conductivity(∼0.026 W m^(−1) K^(−1)).Compared with rigid porous fibrous materials,the EFPCs had deformability and excellent shape *** contrast to flexible materials,the EFPCs possessed high compressive stress,thus endowing them with good resistance to *** emergence of this fascinating material may provide new insights for candidate materials in thermal insulation and other fields.

关键词： Silica fiber Facile press filtration Elastic fibrous porous ceramics High compressive stress Thermal insulation

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连续铸钢技术的发展

钢铁 1979年第5期 49-56页

作者：徐宝升

连铸技术在钢铁工业的应用,近几年来得到很快的发展.国外连铸技术的提高主要表现在:1.连铸机生产能力的提高;2.连铸设备设计及制造技术的改进;3.铸坯质量的提高;4.浇铸钢种的扩大;5.自动化及过程控制技术的应用.还发展了一些新型连铸机... 详细信息

连铸技术在钢铁工业的应用,近几年来得到很快的发展.国外连铸技术的提高主要表现在:1.连铸机生产能力的提高;2.连铸设备设计及制造技术的改进;3.铸坯质量的提高;4.浇铸钢种的扩大;5.自动化及过程控制技术的应用.还发展了一些新型连铸机,如离心连铸机、水平连铸机、带式连铸机和轮带式连铸机等.我国从1957年就开始研究连铸技术.1960年试验成功了弧形连铸机.1964年建成了第一台弧形板坯连铸机.随着我国钢铁工业的发展,连铸技术必将得到相应的发展.我国现有的一些小型轧机需要50～70毫米小方坯,因而提出了发展高速小方坯连铸机解决供坯的问题.

关键词：连铸机中间罐钢铁工业连续浇铸机冶金工业浇铸设备(冶金) 连铸设备铸坯断面连铸技术多炉连浇钢水温度拉坯速度钢液面坯壳厚度铸坯质量钢流连铸比

Selenium deficiency exacerbates ROS/ER stress mediated pyroptosis and ferroptosis induced by bisphenol A in chickens thymus

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Journal of Environmental Sciences 2025年第2期148卷 13-26页

作者： Kun Wang xu Shi Hongjin Lin Tong xu Shiwen xu College of Veterinary Medicine Northeast Agricultural UniversityHarbin 150030China Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment Harbin 150030China

Bisphenol A(BPA)is an industrial pollutant that can cause immune *** acts as an antioxidant,as selenium deficiency often accompanies oxidative stress,resulting in organ *** study is the first to demonstrate that BPA and/or selenium deficiency induce pyroptosis and ferroptosis-mediated thymic injury in chicken and chicken lymphoma cell(MDCC-MSB-1)via oxidative stress-induced endoplasmic reticulum(ER)*** established a broiler chicken model of BPA and/or selenium deficiency exposure and collected thymus samples as research subjects after 42 *** results demonstrated that BPA or selenium deficiency led to a decrease in antioxidant enzyme activities(T-AOC,CAT,and GSH-Px),accumulation of peroxides(H2O2 and MDA),significant upregulation of ER stress-relatedmarkers(GRP78,IER 1,PERK,EIF-2α,ATF4,and CHOP),a significant increase in iron ion levels,significant upregulation of pyroptosis-related gene(NLRP3,ASC,Caspase1,GSDMD,IL-18 and IL-1β),significantly increase ferroptosis-related genes(TFRC,COX2)and downregulate GPX4,HO-1,FTH,*** vitro experiments conducted in MDCC-MSB-1 cells confirmed the results,demonstrating that the addition of antioxidant(NAC),ER stress inhibitor(TUDCA)and pyroptosis inhibitor(Vx765)alleviated oxidative stress,endoplasmic reticulum stress,pyroptosis,and ***,this study concludes that the combined effects of oxidative stress and ER stress mediate pyroptosis and ferroptosis in chicken thymus induced by BPA exposure and selenium deficiency.

关键词： Bisphenol A Selenium deficiency ROS/ER stress Pyroptosis Ferroptosis Thymic injury

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剪切变形对梁弯曲影响的一种新解法

西南石油学院学报 1987年第4期 72-82页

作者：许宝胜西南石油学院石油机械系

文献[1]中,介绍了求解剪切变形对梁弯曲影响问题的试凑法,费时费事,特别是对初学者尤感困难。本文介绍了一种新解法,概念清晰,推证严谨所得结果与试凑法完全相同,文中还引用了算例加以说明应用。

关键词：剪切变形梁弯曲挠曲线微分方程梁的挠度截面转角剪切位移边界条件新解法

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 60-66页

作者： Guo-Fu xu Department of Physics Shandong UniversityJinan 250100China

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era,building accurate intermediate-scale nonadiabatic holo-nomic quantum computers is clearly *** that measurements are the sole means of extracting information,they play an indispensable role in nonadiabatic holonomic quantum ***,developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great ***,while much attention has been given to the research on nonadiabatic holonomic gates,the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely *** this study,we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum *** reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic *** these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

基于第二语言习得理论的通用手语教材开发研究

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现代特殊教育 2018年第18期 52-57,66页

作者：傅敏许保生浙江特殊教育职业学院特教康复系杭州310023

开发通用手语培训教材要遵循第二语言习得理论,选择日常生活中常用的典型语言材料,提供合适有效的语言交际情境。要遵循从易到难、循序渐进的原则,符合学习者的认知规律。教材可按主题设置单元,每单元由情景对话、词汇学习、练习系统和... 详细信息

开发通用手语培训教材要遵循第二语言习得理论,选择日常生活中常用的典型语言材料,提供合适有效的语言交际情境。要遵循从易到难、循序渐进的原则,符合学习者的认知规律。教材可按主题设置单元,每单元由情景对话、词汇学习、练习系统和手语小常识四个板块构成。根据第二语言学习理论,通用手语教学可以选择使用认知教学法、交际语言教学法、合作语言教学法、语言经验教学法等教学方法,帮助学习者提高手语学习效率。

关键词：通用手语教材开发第二语言习得理论通用手语教学

Analysis of vibration response characteristics of subway station and superstructure with hard combination

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 271-281页

作者： Jia Jinglong xu Weiping Liu xu Wei Yong Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSchool of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Intelligent Geotechnics and Tunnelling Chengdu 610031China China Railway Eryuan Chongqing Survey and Design Institute Co.Ltd. Chongqing 400023China

The vibration response and noise caused by subway trains can affect the safety and comfort of *** study the dynamic response characteristics of subway stations and superstructures under train loads with a hard combination,a numerical model is developed in this *** indoor model test verified the accuracy of the numerical *** influence laws of different hard combinations,train operating speeds and modes were studied and evaluated *** results show that the frequency corresponding to the peak vibration acceleration level of each floor of the superstructure property is concentrated at 10–20 *** vibration response decreases in the high-frequency parts and increases in the lowfrequency parts with increasing distance from the ***,the factors,such as train operating speed,operating mode,and hard combination type,will affect the vibration of the *** vibration response under the reversible operation of the train is greater than that of the unidirectional *** operating speed of the train is proportional to its vibration *** vibration amplification area appears between the middle and the top of the superstructure at a higher train *** vibration acceleration level will exceed the limit value of relevant regulations,and vibration-damping measures are *** the scope of application,this study provides some suggestions for constructing subway stations and superstructures.

关键词： subway station superstructure vibration response hard combination