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轨道交通工程业主WBS方法与实践

华中科技大学学报（城市科学版） 2002年第4期19卷 7-10页

作者：郭志涛丁烈云华中科技大学土木工程与力学学院湖北武汉430074

WBS(WorkBreakdownStructure ,工作分解结构 )是按照系统的原理把项目分解为可控的且宜操作的工作单元 ,并对工作单元的内容进行界定 .因此 ,讨论业主WBS的意义 ,分析其与一般施工WBS分解不同之处 ,总结了业主在分解过程中可用的一般分... 详细信息

WBS(WorkBreakdownStructure ,工作分解结构 )是按照系统的原理把项目分解为可控的且宜操作的工作单元 ,并对工作单元的内容进行界定 .因此 ,讨论业主WBS的意义 ,分析其与一般施工WBS分解不同之处 ,总结了业主在分解过程中可用的一般分解方法和适用于轨道工程的分解方法 .最后。

关键词： WBS 轨道交通业主

Effect of Micro-scale Y Addition on the Fracture Properties of Al–Cu–Mn Alloy

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 217-227页

作者： Ting-Biao guo Feng Zhang Wan-Wu ding zhi Jia School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China Key Laboratory of Nonferrous Alloys and Processing of Ministry of Education Lanzhou 730050China

Rare earth(RE) elements have positive e ects on Al alloy, while most research is focused on microstructure and mechanical properties. As important application indices, toughness and plasticity are properties that are sensitive to alloy fracture characteristics, and few research studies have characterized the fracture properties of Al–Cu–Mn alloy on RE elements. The e ect of di erent contents of Y on the fracture properties of Al–Cu–Mn alloy is investigated. T6 heat treatment(solid solution and artificial aging treatment), optical microscope(OM), scanning electron microscopy(SEM) and energy dispersive spectrometer(EDS) methods are applied to the alloy. Results showed that when Y ele?ment is present at 0.1%, the section of the as?cast alloy has smaller sized dimples and the fracture mode presents duc?tile features. Slight changes in hardness are also observed and maintained at about 60 HV. With increasing content of the RE element Y from 0.1 to 0.5%, the θ phase and Cu atoms in the matrix were reduced and most stopped at Grain boundaries(GBs). Micro?segregation and an enriched zone of Y near the GBs gradually increased. At the same time, the inter?metallic compound AlCuY is aggregated at grain junctions causing deterioration of the micro?structure and fracture properties of the alloy. After T6 treatment, the flatness of the fracture surface was lower than that of all the as?cast alloy showing lots of dimples and teared edges with a significant increase in hardness. When Y content was 0.1%, the strength and hardness of the alloy increased due to refinement of the grain strengthening e ect. The content of Y elements segregated in the inter?dendritic zone and GBs is reduced. Plasticity and deformation compatibility also improved, making cracks di cult to form and merge with each other along adjacent grain junctions and providing an increased potential for ductile fracture. This paper proposes the addition of RE Y as an e ective and prospective strategy to improve the fra

关键词： Al–Cu–Mn alloy Solid solution Fracture toughness Mechanical properties

基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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基于分子束外延技术可控制备Ga原子团簇的研究

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原子与分子物理学报 2025年第3期42卷 77-84页

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结... 详细信息

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结果表明,Ga源温度的升高导致Ga的蒸发量增加,进而沉积在Si衬底表面的Ga原子增多,Ga原子自组装成团簇,最终表现为Ga原子团簇的高度升高.第二组对照实验分别在3 s、6 s、10 s、40 s、50 s、60 s的沉积时长下制备Ga原子团簇.实验结果表明,沉积时长增加导致团簇的高度逐渐增加,主要由新吸附原子和竞争效应驱动.第三组对照实验分别在0 s、60 s、300 s的退火时长下制备Ga原子团簇.实验结果表明,退火时长的增加导致团簇的高度下降和团簇内的原子重新排列和分布有关.第四组对照实验分别在420℃、500℃的退火温度下制备Ga原子团簇.实验结果表明,升温至500℃退火会促进Ga原子团簇呈现有序排列,是表面原子的热运动和Ga原子团簇与Si(100)的晶格匹配度的共同作用的结果.

关键词： MBE Ga原子团簇 Ga源温度沉积时长退火时长

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In-vivo retinal imaging by optical coherence tomography using an RSOD-based phase modulator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 607-612页

作者： Ling WANG zhi-hua ding guo-hua SHI Yu-dong ZHANG State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China Institute of Optics and Electronies Chinese Academy of Sciences Chengdu 610209 China

Fourier-domain rapid scanning optical delay line (RSOD) was introduced for phase modulation and depth scanning in a time-domain optical coherence tomography (TD-OCT) system. Investigation of parameter optimization of RSOD was conducted. Experiments for RSOD characterization at different parameters of the groove pitch, focal length, galvomirror size, etc. were performed. By implementing the optimized RSOD in our established TD-OCT system with a broadband light source centered at 840 nm with 50 nm bandwidth, in vivo retina imaging of a rabbit was presented, demonstrating the feasibility of high-quality TD-OCT imaging using an RSOD-based phase modulator.

关键词： Optical coherence tomography (OCT) Phase modulation Retina imaging

Effect of nitrogen introduction methods on the microstructure and properties of gradient cemented carbides

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 709-716页

作者： Tian-en Yang Ji Xiong Lan Sun zhi-xing guo ding Cao School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China

Gradient cemented carbides with the surface depleted in cubic phases were prepared following normal powder metallurgical *** zone formation and the influence of nitrogen introduction methods on the microstructure and performance of the alloys were *** results show that the simple one-step vacuum sintering technique is doable for producing gradient cemented *** structure formation is attributed to the gradient in nitrogen activity during sintering,but is independent from nitrogen introduced methods.A uniform carbon distribution is found throughout the ***,the transverse rupture strength of the cemented carbides can be increased by a gradient *** nitrogen carriers give the alloys distinguishing microstructure and mechanical properties,and a gradient alloy with ultrafine-TiC0.5N0.5 is found optimal.

关键词： gradient cemented carbide gradient methods nitrogen microstructure mechanical properties sintering

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新型城市轨道动车组制动系统方案设计

上海铁道大学学报 1999年第12期20卷 12-15页

作者：吴萌岭姜靖国应之丁上海铁道大学机械工程系上海200331

为了解决国产新型城市轨道交通车辆的关键技术之一———制动系统，作者根据在２００ｋｍ／ｈ电动车组制动系统研制工作中积累的经验，提出了新型城市轨道电动车组制动系统的设计原则，并拟定了适用于新型城市轨道电动车组的制动系统... 详细信息

为了解决国产新型城市轨道交通车辆的关键技术之一———制动系统，作者根据在２００ｋｍ／ｈ电动车组制动系统研制工作中积累的经验，提出了新型城市轨道电动车组制动系统的设计原则，并拟定了适用于新型城市轨道电动车组的制动系统设计方案。该方案能满足不同要求的城市轨道电动车组。

关键词：城市轨道车辆电动车组制动系统

Evolution of MnS and MgO·Al_(2)O_(3) inclusions in AISI M35 steel during electroslag remelting

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Journal of Iron and Steel Research International 2021年第12期28卷 1605-1616页

作者： ding-li Zheng guo-jun Ma Xiang Zhang Meng-ke Liu zhi Li Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina

Thermodynamics and kinetics of dissociation and precipitation of MnS inclusions,as well as the effect of reoxidation in liquid steel on MgO·Al_(2)O_(3)inclusions in AISI M35 steel during electroslag remelting(ESR)process were *** inclusions found in the consumable electrode were MnS,MgO·Al_(2)O_(3)and MnS adhering to MgO·Al_(2)O_(3).MnS inclusions were nearly spherical and ellipse in morphology,and most of them were less than 2μm in ***·Al_(2)O_(3)inclusions were polygonal and nearly spherical and most about 1-4μm in *** inclusions in ESR ingot observed by scanning electron microscopy-energy-dispersive X-ray spectrometer were polygonal and nearly spherical MgO·Al_(2)O_(3).MnS inclusions in the consumable electrode were completely dissociated before the liquid film dripping into molten slag *** controlling step of MnS inclusions dissociation was the mass transfer of[Mn]in the liquid *** the solidification process,the thermodynamic driving force could not meet MnS inclusions precipitation before the solid fraction exceeds 0.996,and the kinetics condition is too poor for the growth of MnS inclusions in the steel when the solid fraction is larger than ***·Al_(2)O_(3)inclusions in ESR ingot originated from the remained MgO·Al_(2)O_(3)inclusions in consumable electrode and the fresh ones formed by the reaction between dissolved magnesium,oxygen and aluminum in liquid steel.

关键词： Electroslag remelting Inclusion MnS MgO·Al_(2)O_(3) AISI M35 steel

Adherent coating on gradient cemented carbide with ultrafine Ti(C_(0.5),N_(0.5))

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Rare Metals 2015年第6期34卷 413-420页

作者： Tian-En Yang Lan Sun Ji Xiong zhi-Xing guo Lei Wang ding Cao School of Manufacturing Science and Engineering Sichuan University Institute of System Engineering Chinese Academy of Engineering Physics

Gradient cemented carbide is usually employed as the snbstrate for coated carbide insert. In this work, gradient cemented carbide with ultrafine Ti（C0.5,N0.5） was prepared and its microstructure and properties were researched. Moreover, this novel substrate was coated to investigate cutting performance. It is found that the average WC grain size in the gradient zone is larger than that in the bulk. Owing to ultrafine Ti（C0.5,N0.5） introduction, gradient cemented carbide prepared by vacuum sintering exhibits full densification. By contrast, the gradient cemented carbide with ultrafine Ti（C0.5,N0.5） shows higher transverse rupture strength （TRS） and hardness than the homogenous one. Gradient cemented carbide suffers small TRS reduction after coating, and the bonding between coatings and gradient substrate is tidy and compact. The coated gradient cemented carbide shows much better endurance and impact resistance than the coated homogenous one. It confirms the superiority of gradient cemented carbide when used as the substrate for coating inserts.

关键词： Gradient cemented carbide UltrafineTi(C0.5,N0.5) Vacuum sintering Transverse rupturestrength Cutting performance