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Feasibility analysis and process characteristics of selective laser ablation assisted milling Inconel 718

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Advances in Manufacturing 2022年第4期10卷 495-519页

作者： Bao-Yu Zhang Yu-Ning Zeng Xue-qin pang Song-qing Li Xiao Liu Wen-Jun Deng School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510641People’s Republic of China

Laser-assisted machining(LAM),as one of the most efficient ways,has been employed to improve the machinability of nickel-based ***,the conventional LAM process usually used high power laser with large spot size,easily leading to high processing costs and overheating of bulk *** this paper,a new approach of selective laser ablation assisted milling(SLA-Mill)process for nickel-based superalloys was proposed,in which low power laser with small spot size was used to selectively ablate the uncut surface in front of the cutting tool,resulting in plentiful surface defects *** defects would significantly weaken the mechanical strength of difficult-to-cut materials,which was different from the thermal“softening”principle of conventional ***,the laser ablation effect with low power and small spot size was first *** relationship between process parameters(e.g.,laser power,cutting speed and cutting depth)and process characteristics of SLA-Mill(e.g.,chip morphology,tool wear and surface integrity)was systematically ***,the chip formation mechanism in the SLA-Mill process was indepth *** show that the SLA-Mill process is an effective approach for enhancing the machinability of nickel-based *** resultant cutting force has a reduction of about 30%at laser power of 60 W,cutting speed of 90 m/min,and cutting depth of 0.1 ***,the chip formation,tool wear,and surface integrity have improved *** general,this paper provides a new route for the application of LAM technology.

关键词： Laser-assisted machining(LAM) Nickel-based superalloys Laser ablation Machinability Milling

Catalyzed oxidation of 2,6-dimethylphenol in Triton X-100 micellar solution

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Chinese Chemical Letters 2007年第3期18卷 349-351页

作者： Jie Zhu Xiang Guang Meng Hai Dong Wang Shan Dong Liu qin Hui pang Juan Du Xian Cheng Zeng College of Chemistry Sichuan University Chengdu 610064 China Bio-Chemistry Experimental Center Jiaxing College Jiaxing 314001 China College of Physics Science Qingdao University Qingdao 266071 China

The oxidative coupling reaction of 2,6-dimethylphenol with H202 catalyzed by a copper（H） Schiff complex in aqueous and Triton X-100 micellar solution under mild conditions was investigated. The kinetics of formation of 3,3＇,5,5＇-tetramethyl-4,4＇- diphenoquinone （DPQ） was studied. Rate constant k2 were obtained. The optimum pH for DPQ generation reaction is 7.25. The main product was DPQ in aqueous buffer solution, but PPE and the oxidized products of PPE remained in Triton X-100 micellar solution.

关键词： 2,6-Dimethylphenol Oxidative coupling Micelle Kinetics

An Automatic Testing System of Scheduling Strategies in Real-Time UNIX

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Journal of Systems Engineering and Electronics 2001年第2期12卷 59-62页

作者： qin Xiao, pang Liping & Han Zongfen Department of Computer Science, Huazhong University of Science and Technology, Wuhan 430074, P. R. China Department of Computer Science Huazhong University of Science and Technology Wuhan 430074 P. R. China

This paper proposes a formal model of the automatic testing system for scheduling strategies in real-time UNIX and describes the algorithm of the key part of the system. The model of the system is an important technology of the automatization of software development. According to the model presented in the paper, many different kinds of automatic testing systems can be designed and developed easily. At the end of the paper, the prototype proves the feasibility of the model and design.

关键词： Algorithms Automatic testing Real time systems Scheduling Software prototyping

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第三国在中美经济竞争中的选择偏好研究

世界经济与政治 2022年第4期 30-61,157页

作者：庞琴中山大学国际关系学院广州510250 中山大学“一带一路”研究院广州510250

第三国如何在中美之间选边站队是影响中美战略竞争乃至国际秩序转型的关键因素,哪些因素促使第三国倾向于同中国或美国保持更紧密的经济关系因而成为值得关注的议题。第三国在选边过程中,除采用权力、相互依赖和威胁感知等相同标准比较... 详细信息

第三国如何在中美之间选边站队是影响中美战略竞争乃至国际秩序转型的关键因素,哪些因素促使第三国倾向于同中国或美国保持更紧密的经济关系因而成为值得关注的议题。第三国在选边过程中,除采用权力、相互依赖和威胁感知等相同标准比较中美并选择更“有利可图”的一方,还会考虑中美两国作为“先入者”和“后入者”同本国的经济连接方式存在显著差异的事实。换言之,第三国对中美经济的情感和期待存在明显差异,这将影响它们的选边倾向。从经济学的角度,可以把中美经济竞争看作第三国市场中“先入者—后入者”之间的争夺,第三国的选择偏好同它们对美国的忠诚感和对中国的获益感直接相关。这两个因素在中美经济权力对比发生变化背景下会强化第三国的态度转变,即随着中国经济实力上升,对美国有忠诚感的第三国比没有忠诚感的第三国更可能放弃美国,对中国有获益感的第三国比没有获益感的第三国会更积极选择中国。对16个国家18443名受访者的数据进行的定量检验显著支持这一结论。

关键词：中美经济竞争权力转移第三国选边对冲

冲突视角下的美国对外经济制裁——规范成本、相互依赖与制裁僵局

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世界经济与政治 2024年第1期 108-137,174,175页

作者：庞琴中山大学国际关系学院珠海510275 中山大学区域国别研究院珠海510275

美国对外经济制裁是冷战后国际政治经济学关注的重点。既有研究主要以西方学者为主体,探讨制裁的有效性及其影响因素。作者采用被制裁国的视角,将制裁视为美国以经济手段与制裁目标国进行的政治冲突,聚焦于冲突烈度最高的制裁僵局,并以... 详细信息

美国对外经济制裁是冷战后国际政治经济学关注的重点。既有研究主要以西方学者为主体,探讨制裁的有效性及其影响因素。作者采用被制裁国的视角,将制裁视为美国以经济手段与制裁目标国进行的政治冲突,聚焦于冲突烈度最高的制裁僵局,并以信号理论为基础解释导致美国与目标国进入制裁僵局的动机和实力两方面的因素。就动机而言,美国发起的制裁可分为规范性制裁和自利性制裁两类。在规范性制裁中,美国为维持领导秩序所承担的规范成本越高,双方进入僵局的概率越大。就实力而言,双方贸易依赖可分为进口和出口两方面,作者通过引入全球价值链理论,指出目标国与美国在进口贸易方面不对称的相互依赖在两者权力差异中更加重要。它极易造成战略误判即信号扭曲,导致双方进入制裁僵局的概率出现非线性的正U形曲线关系,即当目标国对美国进口的依赖度从非常低逐步上升到中等水平,目标国和美国进入僵局的概率会减小;但是随着依赖度从中等水平上升到非常高,该概率又会逐步增大。随着中美之间结构性竞争加剧、经济安全作为当前首要重任的情况下,这一发现也具有一定的现实意义。

关键词：经济制裁规范性制裁规范成本相互依赖进口依赖度

中美权力变化与美国公众对“中国威胁”的认知

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世界经济与政治 2020年第7期 69-96,157,158页

作者：庞琴中山大学国际关系学院中山大学“一带一路”研究院广州510275

权力变化引起国际冲突的因果机制是当前国际关系理论与政策研究中的热点。现有研究较少从心理学特别是威胁认知的角度探讨该问题。以当前中美关系为案例,通过对美国公众的调查数据进行中介与调节效应分析,可以得出以下发现:第一,中国经... 详细信息

权力变化引起国际冲突的因果机制是当前国际关系理论与政策研究中的热点。现有研究较少从心理学特别是威胁认知的角度探讨该问题。以当前中美关系为案例,通过对美国公众的调查数据进行中介与调节效应分析,可以得出以下发现:第一,中国经济与军事实力的增长通过影响美国民众对本国未来经济走势的信心以及对中美两国发生冲突的可能性的判断这两种途径作用于他们的“中国威胁”认知,其中对“冲突可能性的判断”具有更为明显的中介作用。第二,在中美两国目前的权力对比格局下,中国经济与军事实力上升引发美国原有“温和派”特别是产业资本阶层和军事接触派的“中国威胁”认知快速上升,其增长的弹性系数高于原来的“强硬派”即产业劳动力阶层和军事遏制派,导致原先的“温和派”与“强硬派”之间差距缩小,两派对“中国威胁”认知的同质性迅速加强并形成共识,成为支持美国政府对华强硬政策的社会心理基础。上述发现拓展了威胁认知以及权力转移导致冲突的心理动因理论,对解释中美关系的当前变化和未来发展具有一定意义。

关键词：威胁认知增长弹性系数同质性权力转移中美关系

Mass transport in a highly immiscible alloy on extended shear deformation

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Journal of Materials Science & Technology 2023年第3期134卷 197-208页

作者： Miao Song Jia Liu Xiaolong Ma qin pang Matthew J.Olszta Joshua Silverstein Madhusudhan R.Pallaka Peter V.Sushko Suveen N.Mathaudhu Cynthia Powell Arun Devaraj Bharat Gwalani Physical and Computational Sciences Directorate Pacific Northwest National Laboratory902 Battelle BoulevardRichlandWA 99354USA Energy and Environmental Directorate Pacific Northwest National Laboratory902 Battelle BoulevardRichlandWA 99354USA Material Science and Engineering Program University of CaliforniaRiversideCA92521USA Colorado School of Mines 1500 Illinois St.GoldenCO 8040USA Department of Materials Science and Engineering North Carolina State UniversityRaleighNC27695-7907USA State Key Laboratory of Powder Metallurgy Central South Uni-versityChangsha 410083China

Forced mixing to a single-phase or supersaturated solid solution(SSS)and its prerequisite microstructure evolution in immiscible systems has been a focus of research for fundamental science and practical *** the formation of SSS by shear deformation could enable a material design beyond conventional equilibrium microstructure in immiscible ***,a highly immiscible Cu-50 at.%Cr binary alloy(mixing enthalpy of∼20 kJ mol^(−1))was employed to investigate the microstructure evolution and localized tendencies of SSS during severe shear *** results demonstrate the dislocation mediated microstructural refinement process in each phase of the binary alloy and the mechanisms associated with localized solute supersaturation as a function of shear *** grain refinement in the softer Cu phase occurs owing to the strain localization driving the preferential dynamic *** grain refinement of the Cr phase,however,is enabled by the progressive evolution of grain lamination,splitting,and fragmentation as a function of shear *** solute supersaturation is found to be strongly dependent on the local environments that affect the dislocation activity,including the level of microstructure refinement,the interfacial orientation relationship,the mechanical incompatibility,and the localized preferential phase *** initio simulations confirm that it is more favorable to oxidize Cr than Cu at incoherent Cu/Cr interfaces,limiting the mass transport on an incoherent *** results unveil the mechanism underpinning the non-equilibrium mass transport in immiscible systems upon severe deformation that can be applied to produce immiscible alloys with superior mechanical properties.

关键词： Tribology Immiscible alloys Nanostructures Shear deformation Forced mixing Atom probe

CRF:A Scheduling of Multi-Granularity Locks in Object-Oriented Database Systems

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Journal of Systems Engineering and Electronics 1998年第4期9卷 51-57页

作者： qin Xiao & pang Liping(Department of Computer Science, Huazhong University of Science and Technology,Wuhan 430074, P. R. China) Department of Computer Science H azhong University of Science and Technology Wuhan 430074 P. R. China

This paper introduces a multi-granularity locking model (MGL) for concurrency control in object-oriented database system briefiy, and presents a MGL model formally. Four lockingscheduling algorithms for MGL are proposed in the paper. The ideas of single queue scheduling(SQS) and dual queue scheduling (DQS) are proposed and the algorithm and the performance evaluation for these two scheduling are presented in some paper. This paper describes a new idea of thescheduling for MGL, compatible requests first (CRF). Combining the new idea with SQS and DQS,we propose two new scheduling algorithms called CRFS and CRFD. After describing the simulationmodel, this paper illustrates the comparisons of the performance among these four algorithms. Asshown in the experiments, DQS has better performance than SQS, CRFD is better than DQS, CRFSperforms better than SQS, and CRFS is the best one of these four scheduling algorithms.

关键词： Lock scheduling Multi-granularity lock Concurrency control Compatible requestsfirst Single queue scheduling Dual queue scheduling Object-oriented database system

THE STUDY ON THE SYNTHESES OF THREE NEW MICROPOROUS ALUMINOPHOSPHATES BY USING ETHYLENEDIAMINE AS TEMPLATE

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Chinese Chemical Letters 1992年第4期3卷 325-328页

作者： Long YU~* Department of Chemistry, Liaoning University, Shenyang, 110036 Wen qin pang Bepartment of Chemistry, Jilin University, Changchun, 130021

Using ethylenediamine as template, we have hydrothermally synthesized three new microporous aluminophosphate crystals which were named AlPO_4-CJ_3, AlPO_4-CJ_6, AlPO_4-CJ_7, and characterized by means of X-ray powder ... 详细信息

关键词： CJ AS THE STUDY ON THE SYNTHESES OF THREE NEW MICROPOROUS ALUMINOPHOSPHATES BY USING ETHYLENEDIAMINE AS TEMPLATE