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Acta Mechanica Solida Sinica 2022年第2期35卷 344-356页

作者： M.K.ramezani S.ramesh j.Purbolaksono r.Das Centre of Advanced Manufacturing and Materials Processing Department of Mechanical EngineeringFaculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Department of Mechanical Engineering University of PertaminaJakarta 12220Indonesia Sir Lawrence Wackett Aerospace research Centre School of EngineeringRMIT UniversityMelbourneVI 3000Australia

In this work,the stress intensity factors(SIFs)for a wide range of semi-elliptical surface cracks with different inclination angles in a cylindrical bar subjected to pure tension were investigated *** main parameters considered to evaluate the SIFs were the crack size ratio(a/d),the crack aspect ratio(a/c),and the crack inclination angle(0).The dual-boundary element met hod implemented in software BEASY was used to compute the SIF values for *** her more,the general closed-form solutions were proposed to evaluate the corresponding SIFs for Mode I,Mode II and Mode III types of fracture through curve fitting *** solutions can provide accurate and reliable values of stress intensity factors for a crack on a cylindrical bar under pure tension in a rapid way compared to those obtained using computational *** addition,these results can be used as inputs for failure studies and life evaluations of cracked cylinder under working conditions.

关键词： Stress intensity factor Surface crack Solid cylinder Closed-form solution Dual-boundary element method

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

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儿童运动生理研究在运动医学中的任务

体育与科学 1991年第5期 43-44页

作者： Oded bar-Or,姜文凯 M.D

运动对儿童生理的影响在80年代已成为一个热门研究课题。近年来所发表的一系列专题论著,书籍、期刊、杂志等大量论著充分体现了对儿童运动生理日益增强的兴趣。欧洲少儿运动生理研究协作组20年来一直在组

关键词：运动生理少儿儿童运动医学

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转化数据为商业智能

机械设计与制造工程 2010年第2期 72-74页

作者： sas公司 sas公司

仅仅实行精益生产流程并满足客户需求是不够的。面对不断变化的全球市场,企业现在还必须能够预测未来的市场增长和需求,不断调整和适应也将成为企业经营中的一种常态。为从各个系统收集这些数据并从中获取有用信息,公司需要拥有合适的... 详细信息

仅仅实行精益生产流程并满足客户需求是不够的。面对不断变化的全球市场,企业现在还必须能够预测未来的市场增长和需求,不断调整和适应也将成为企业经营中的一种常态。为从各个系统收集这些数据并从中获取有用信息,公司需要拥有合适的数据管理、预测、优化和建模技术。管理人员和其他利益相关方就能随时了解变化和趋势,并根据这些指标做出业务决定。

关键词：商业智能客户需求精益生产生产类型业务规则企业企业管理背景信息背景信念建模技术敏捷性

Quenched Fe moment in the collapsed tetragonal phase of Ca_(1-x)Pr_x Fe_2As_2

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Chinese Physics B 2013年第5期22卷 55-59页

作者：马龙吉高峰代佳 Saha S r Drye T Paglione j 于伟强 Department of Physics Renmin University of China Center for Nanophysics and Advanced Materials Department of PhysicsUniversity of MarylandCollege Park

We report 7sas NMr studies on single crystals of rare-earth doped iron pnictide superconductor Ca1-xPrxFe2As2. In both cases of x = 0.075, 0.15, a large increase of Vq upon cooling is consistent with the tetragonal-collapsed tetragonal structure transition. A sharp drop of the Knight shift is also seen just below the structure transition, which suggests the quenching of Fe local magnetism, and therefore offers important understanding of the collapsed tetragonal phase. At even low temperatures, the 1/75 T1 is enhanced and forms a peak at T ≈ 25 K, which may be caused by the magnetic ordering of the Pr3＋ moments or soin dynamics of mobile domain walls.

关键词： quenched Fe moment collapsed tetragonal phase iron pnictides nuclear magnetic resonance

Effect of Varying Carbon Content and Shot Peening upon Fatigue Performance of Prealloyed Sintered Steels

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journal of Materials Science & Technology 2009年第5期25卷 607-610页

作者： r.Bidulsky M.Actis-Grande M.Kabtov j.Bidulsk Politecnico Torino Alessandria CampusV.T.Michel5Alessandria 15000Italy Institute of Materials research SASWatsonova 47Koice04011Slovakia Technical University of Koice Faculty of MetallurgyLetn9Koice 04200Slovakia

The aim of the work was to find out how the modification of surface treatment and microstructures affect the fatigue characteristics of the considered sintered materials. Two different systems were prepared： as-sintered and shot peened prealloyed sintered （Astaloy CrL based） steels with addition of 0.5% and 0.7% C. Sintering was carried out in laboratory tube furnace in an atmosphere of pure gases 75%N2＋25%H2. The sintering temperature was 1180℃ and sintering time was 60 min. Heating and cooling rates were 10℃/min. Fatigue tests were carried out in symmetric plane bending at stress ratio r=-1 with frequency of about 24 Hz. The presented experimental results showed that prealloyed water-atomised steels, with surface modification, exhibit positive effects on the fatigue failure resistance, and for that reason are suitable for high-performance applications.

关键词： Sintered steels Shot peening Fatigue strength S-N curves

Differential response of tomato genotypes to Xanthomonas-specific pathogen-associated molecular patterns and correlation with bacterial spot (Xanthomonas perforans) resistance

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Horticulture research 2016年第1期3卷 142-147页

作者： Krishna Bhattarai Frank j Louws john D Williamson Dilip r Panthee Department of Horticultural Science North Carolina State UniversityMountain Horticultural Crops Research and Extension CenterMills RiverMills RiverNC 28759USA Department of Plant Pathology North Carolina State UniversityRaleighNC 27695USA Department of Horticultural Science North Carolina State UniversityRaleighNC 27695USA

Plants depend on innate immune responses to retard the initial spread of pathogens entering through stomata,hydathodes or *** responses are triggered by conserved patterns in pathogen-encoded molecules known as pathogen-associated molecular patterns(PAMPs).Production of reactive oxygen species(rOS)is one of the first responses,and the resulting‘oxidative burst’is considered to be a first line of *** this study,we conducted association analyses between rOS production and bacterial spot(BS;Xanthomonas spp.)resistance in 63 genotypes of tomato(Solanum lycopersicum L.).A luminol-based assay was performed on leaf tissues that had been treated with a flagellin 22(flg22),flagellin 28 and a Xanthomonas-specific flg22(flg22-Xac)peptide,to measure PAMP-induced rOS production in each *** genotypes were also assessed for BS disease response by inoculation with Xanthomonas perforans,race *** there was no consistent relationship between peptides used and host response to the BS,there was a significant negative correlation(r=−0.25,Pr disease severity and rOS production,when flg22-Xac was *** response could potentially be used to identify the Xanthomonas-specific Prr allele in tomato,and eventually PAMP-triggered immunity loci could be mapped in a segregating *** has potential significance in tomato improvement.

关键词： eventually injuries specific

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一种中碳钢的疲劳短裂纹特性

食品与生物技术学报 1986年第2期 44-53+90-91页

作者：唐志祥,E.r._(DE LOS)r_(ios) K.j.Miller 无锡轻工业学院机械系谢菲尔德大学英国

用复型技术研究含碳0.4%钢的扭转疲劳的起始阶段和短裂纹特性。发现疲劳短裂纹在铁素体中发生并扩展。裂纹增长速度取决于裂纹端部塑性范围的大小和程度。因而每循环的裂纹增长正比于滑移带强度。裂纹扩展的减速和可能停止证明晶界是裂... 详细信息

用复型技术研究含碳0.4%钢的扭转疲劳的起始阶段和短裂纹特性。发现疲劳短裂纹在铁素体中发生并扩展。裂纹增长速度取决于裂纹端部塑性范围的大小和程度。因而每循环的裂纹增长正比于滑移带强度。裂纹扩展的减速和可能停止证明晶界是裂纹扩展的强障碍。升高应力值后,原有的不扩展裂纹可能产生支裂纹或连接其它裂纹继续扩展。这个过程反复到一个或多个主导性裂纹的应力达到能导至破坏的继续增长的临界值为止。

关键词：疲劳短裂疲劳力学短裂机理中碳钢/疲劳特性短裂纹

传染病暴发的多尺度特征与系统性防治——基于COVID-19疫情的分析

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北京师范大学学报（自然科学版） 2020年第6期56卷 781-787页

作者：陈清华李小萌沈忱 Yaneer bar-YAM 北京师范大学系统科学学院北京100875 新英格兰复杂系统研究所美国马萨诸塞州剑桥02139

从复杂系统科学角度出发,基于系统组元的相互作用和复杂度曲线,揭示了传染病暴发的复杂性及其多尺度特征;依据多尺度必要多样性法则,探讨了从个人到群体可行的系统性防控手段.结果表明:只有通过个人、群体、国家之间的合作互助,才能做好... 详细信息

从复杂系统科学角度出发,基于系统组元的相互作用和复杂度曲线,揭示了传染病暴发的复杂性及其多尺度特征;依据多尺度必要多样性法则,探讨了从个人到群体可行的系统性防控手段.结果表明:只有通过个人、群体、国家之间的合作互助,才能做好COVID-19全球性应对、构建有效应对传染病的韧性世界.

关键词：复杂系统科学传染病多尺度复杂度曲线韧性

The radiative decay D^(0)→ K^(*0)γ with vector meson dominance

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Chinese Physics C 2018年第4期42卷 135-141页

作者： j. M. Dias V. r. Debastiani ju-jun Xie E. Oset Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Departamento de Física Teórica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain Instituto de Física Universidade de S？o Paulo C. P. 66318 05389-970 S？o Paulo SP Brazil

Motivated by the experimental measurements of D0 radiative decay modes, we have proposed a model to study the D0→ K＊0γ decay, by establishing a link with D0→ K＊0V （V=ρ0, ω） decays through the vector meson dominance hypothesis. In order to do this properly, we have used the Lagrangians from the local hidden gauge symmetry approach to account for Vγ conversion. As a result, we have found the branching ratio B[D0→ K＊0γ]=（1.55-3.44）×10-4, which is in fair agreement with the experimental values reported by the Belle and Babar collaborations.

关键词： radiative decay vector meson dominance local hidden gauge symmetry