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Influence Mechanism of Cerium on the Threshold of Short Fatigue Crack for Aluminum-lithium Alloy 2090

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Rare Metals 2001年第1期20卷 32-37页

作者： zheng chen, yongxin wang, bing liu, xiaoling li, Qilong Wei (School of materials science.and engineering, northwestern polytechnical university. xi’an 710072. china) 西北工业大学陕西西安 710072

The thresholds of short fatigue cracks for aluminum-lithium alloys 2090 and 2090+Ce are quantitatively evaluated. The essential reason resulting in stronger short crack effect has been ascertained. Influence of cerium on the threshold of short fatigue cracks for aluminum-lithium alloy 2090 was investigated. The results show that, by adding Ce into this alloy, DeltaK(i) and DeltaK(***) are increased. The influence mechanism of Ce on the threshold of short fatigue crack for alloy 2090 was explored fi om the bound energy, T, phase, the energy of anti-phase boundary, the energy of super-lattice intrinsic stacking fault and the electron bonds. By adding Ce into alloy 2090, the bound energy of Cu atom in this alloy is increased; the effect of thinning and dispersing T, phase is obtained; the effect of increasing the energy of anti-phase boundary and decreasing the energy of super-lattice intrinsic stacking fault for delta ' phase can be achieved.

关键词： aluminum-lithium alloy Ce short fatigue crack bound energy fault energy

Strain engineering of Pt-based electrocatalysts for oxygen reaction reduction

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Frontiers in Energy 2024年第2期18卷 241-262页

作者： Zeyu wang Yanru liu Shun chen Yun zheng xiaogang FU Yan ZHANG wanglei wang State Key Laboratory of Solidification Processing Atomic Control and Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Dental MaterialsSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China Institute of New Energy materials and engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)are playing irreplaceable roles in the construction of the future sustainable energy ***,the insufficient performance of platinum(Pt)-based electrocatalysts for oxygen reduction reaction(ORR)hinders the overall efficiency of *** the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic *** this paper,insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in ***,recent advances in understanding the strain effects on ORR catalysts are comprehensively ***,strain engineering methodologies for adjusting Ptbased catalysts are comprehensively ***,further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.

关键词： strain engineering Pt-based catalysts oxygen reduction reaction(ORR) catalytic performance proton exchange membrane fuel cells(PEMFCs)

Computer simulation of interface evolution for an Al-li alloy during early aging stage

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Rare Metals 2004年第3期23卷 279-285页

作者： TANGliying wangyongxin chenzheng LUYanli ZHANGJianjun departmentofmaterialsscienceandengineering NorthwesternPolytechnicalUniversityXi＇an710072China departmentofmaterialsscienceandengineering NorthwesternPolytechnicalUniversityXi＇an710072China

The nucleation of ordered phase was simulated based on microscopic diffusionequation and the assumptions of the classical nucleation theory were examined. The quantitativecalculations of interface thickness evolution were accomplished for the first time. It was foundthat the interfaces between ordered phase and disordered matrix were diffuse. The interfacethickness decreased with time, from the initial 1.2 nm to an equilibrium value 0.6 nm. The ratios ofthe radius of ordered particles and the interface thickness monotonously increased, but they wereof the same order of magnitude all the time. The sharp interface assumption should not be adopted inthis stage. For the Al-10% li (atom fraction) alloy aged at 192℃, the assumptions of the classicalnucleation theory disagreed with the facts. The phase transformation followed the non-classicalnucleation mechanism and the applicable scope of the classical nucleation should be confined.

关键词： metal material interface computer simulation non-classical nucleationtheory

Atomic-scale computer simulation for early precipitation process of Ni75 Al10 V15 alloy

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Progress in Natural science:materials International 2004年第3期 49-54页

作者： ZHAO Yuhong*, chen zheng, wang yongxin and LU Yanli (department of materials science.and engineering, northwestern polytechnical university. xi’an 710072. china)

The kinetic model for a ternary system is introduced based on the microscopic diffusion form of the phase field equations for a binary alloy. The equation is solved in the reciprocal space. This model is used to investigate the early precipitation process of Ni 75 Al 10 V 15 by simulating the atomic pictures of the two ordered phases and calculating the order parameters of γ ′(Ni 3Al) phase. Simulation results show that the γ ′ ordered phases precipitate from the disordered matrix by a non classical nucleation mechanism, and the nonstoichiometric γ ′ ordered phase appears first and then transforms into the stoichiometric one. Clusters of V atoms appear at the γ ′ phase boundaries followed by the formation of the nonstoichiometric θ ordered phase. The farther the location from γ ′ phase boundary is, the lower the order degree of θ phase is. There exist two kinds of DO 22 ordered domains: a horizontal one and a vertical one, related to their adjacent γ ′ phase boundaries. The model could describe the atomic ordering and composition clustering simultaneously, and any a priori assumption about the new phase structure and precipitation mechanism etc. is unnecessary.

关键词： early precipitation process computer simulation Ni 75 Al 10 V 15 alloy.

Computer simulation for the precipitation process of Ni75Al7.5V17.5 alloy

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Progress in Natural science:materials International 2004年第12期 67-71+108页

作者： li Yongsheng*, chen zheng, LU Yanli, wang yongxin and ZHANG Jianjun(department of Material science.and engineering, northwestern polytechnical university. xi’an 710072. china) departmentofmaterialscienceandengineering NorthwesternPolytechnicalUniversityXi＇an710072China departmentofmaterialscienceandengineering NorthwesternPolytechnicalUniversityXi＇an710072China

The precipitation mechanism of Ni 75 Al 7.5 V 17.5 alloy above the L1 2 instability line, between the L1 2 and D0 22 instability lines and below the D0 22 instability line are studied using microscopic phase field kinetic equation. This paper is aimed at investigating the effect of temperature on precipitation mechanism and morphological evolution of the alloy. Our simulations demonstrate that the precipitation is a mixed mechanism of non classical nucleation growth and spinodal decomposition above the L1 2 instability line. It needs certain thermal fluctuations for nucleation and the number of θ phases is small at this temperature. The precipitation mechanism of γ′ phase is congruent ordering followed by spinodal decomposition, and θ phase is a mixed mechanism of non classical nucleation growth and spinodal decomposition between the L1 2 and D0 22 instability lines. The mechanism below the D0 22 instability line is similar to that between the L1 2 and D0 22 instability lines. With the decrease of the temperature, ordering and phase separation becomes fast, the dimension of γ′ phase becomes small, the shape transforms from equiaxed to block, the dimension of θ phase becomes large and the shape transforms from strip to circle.

关键词： precipitation mechanism atomic configuration order parameter Ni75Al7.5V17.5 alloys computer simulation.

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磁场对含稀土铝锂合金断裂特征的影响

中国稀土学报 2002年第3期20卷 252-255页

作者：王西宁陈铮刘兵西北工业大学材料科学与工程学院陕西西安710072

以含铈铝锂合金为研究对象 ,研究了磁场对含稀土铝锂合金时效过程的影响 ,从断裂特征及微观组织两方面分析了磁场作用规律。实验结果表明 :未加磁场时 ,合金的断裂特征以准解理断裂为主 ;扁平晶粒厚度不匀。在磁场作用下 ,此合金的断裂... 详细信息

以含铈铝锂合金为研究对象 ,研究了磁场对含稀土铝锂合金时效过程的影响 ,从断裂特征及微观组织两方面分析了磁场作用规律。实验结果表明 :未加磁场时 ,合金的断裂特征以准解理断裂为主 ;扁平晶粒厚度不匀。在磁场作用下 ,此合金的断裂特征与微观组织发生明显改观 ,随磁感应强度增强 ,合金主断裂面上准解理断裂特征减弱 ,同时二次裂纹增多 ,分层比例升高 ;扁平晶粒厚度变薄 ,尺寸趋于均匀。用少体物理理论 ,探讨了磁场对含稀土合金原子扩散过程的影响 ,为进一步研究稀土元素在磁场中的行为及其局域效应提供了一定的实验依据。

关键词：磁场稀土铝锂合金断裂特征微观组织作用规律

陶瓷材料断裂韧性与缺口半径　Ⅱ　断裂韧性估算方法

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无机材料学报 1997年第2期12卷 218-228页

作者：王锋会郑修麟路民旭孙中禹西北工业大学材料科学与工程系西安710072 西安石油管材研究中心西安710061 空军通讯工程学院西安710070

在陶瓷材料裂纹尖端存在一个断裂过程区，当断裂过程区内平均应力达到断裂强度时．裂纹扩展．本文由理论推导并结合实验数据．得到了断裂过程区的大小是平均晶粒直径的四倍．并由平均应力断裂模型，给出了陶瓷材料断裂韧性和缺口半径及... 详细信息

在陶瓷材料裂纹尖端存在一个断裂过程区，当断裂过程区内平均应力达到断裂强度时．裂纹扩展．本文由理论推导并结合实验数据．得到了断裂过程区的大小是平均晶粒直径的四倍．并由平均应力断裂模型，给出了陶瓷材料断裂韧性和缺口半径及平均晶粒直径之间的关系式，由此关系式可以用宽缺口试件测出的断裂韧性去估算陶瓷材料的本质断裂韧性．

关键词：缺口半径断裂韧性估算模型陶瓷材料

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陶瓷切口强度的概率分布(Ⅰ)基本表达式

无机材料学报 1998年第4期13卷 449-456页

作者：鄢君辉郑修麟赵康王锋会西北工业大学材料科学与工程系西安710072

本文对Al2O3陶瓷的强度实验结果进行了进一步分析，分析结果表明：陶瓷的弯曲切口强度和弯曲断裂强度的实验结果同时服从正态分布、对数正态分布和两参数Weibull分布．进而根据脆性材料切口强度表达式和概率论一般原理，求得了切口强度... 详细信息

本文对Al2O3陶瓷的强度实验结果进行了进一步分析，分析结果表明：陶瓷的弯曲切口强度和弯曲断裂强度的实验结果同时服从正态分布、对数正态分布和两参数Weibull分布．进而根据脆性材料切口强度表达式和概率论一般原理，求得了切口强度和弯曲强度统计特征参量间的相互关系表达式，并进行了验证．

关键词：陶瓷弯曲强度切口强度强度表达式

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai Wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin chen Danping chen Fuqing chen Fusan chen Gang chen Guoming chen Hua-xing chen Huirun chen Jinhui chen Ji-Yuan chen Kai chen Mali chen Mingjun chen Mingshui chen Ning chen Shanhong chen Shanzhen chen Shao-Long chen Shaomin chen Shiqiang chen Tianlu chen Wei chen xiang chen xiaoyu chen xin chen Xun chen Xurong chen Ye chen Ying chen Yukai chen Zelin chen Zilin chen Gang chen Boping chen Chunhui chen Hok Chuen cheng Huajie cheng Shan cheng Tongguang cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui xiaohao Cui Zhaoyuan Cui Brunella D'Anzi ling-Yun Dai xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH university.of science.and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui university HefeiAnhui Applied Physics department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu university Institute of ScienceVaranasi Bandirma Onyedi Eylul university Bandirma Beihang university Beijing Beijing Computational science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal university Beijing Brown university ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad university Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo university Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal university WuhanHubei Central South university ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced science.and Technology Beijing china Institute of Atomic Energy Beijing china Jiliang university HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china university.of Geosciences Beijing china university.of Geosciences WuhanHubei china university.of Mining and Technology XuzhouJiangsu china West Normal university NanchongSichuan Chongqing university Department of PhysicsChongqing Chulalongkorn university Bangkok City university.of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell university IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu university DalianLiaoning Dalian university.of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East china university.Of science.and Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2)s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2015)and the Conceptual Design Report(CDR,2018),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2027-2028,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2030s.

关键词： initiated exceeding precise