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国际医学放射学杂志 2024年第2期 253-253页

作者： j.liu Y.L.Qu j.li W.Z.He X.Y.Chen X.li 朱婉秋

摘要目的探讨成人肥胖早期左室(LV)心肌组织特征及其与区域脂肪分布和异位脂肪沉积的关系。方法前瞻性纳入49例肥胖成人[平均体质量指数(29.9±2.0)kg/m2]和44

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Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured individually.The coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this paper.The endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically investigated.Results indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the endwall.Thus,cooling failure occurs,and the endwall’s thermal load is badly increased.The film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being suppressed.In addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged significantly.The best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side endwall.When the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

Effect of arc sprayed coatings on tensile properties of a type 316 steel

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 95-99页

作者： liU Gui-min MA li-li K.j.Kurzydlowski Faculty of Materials Science and Engineering Academy of Armored Force EngineeringBeijing 100072 China Faculty of Materials Science and Engineering Academy of Armored Force EngineeringBeijing 100072 China Faculty of Materials Science and Engineering Warsaw University of Technology Warsaw Poland

The effect of Al- and AlSiRE-coatings obtained by arc spray (AS) and high velocity arc spray (HVAS) technologies, on the tensile properties of type 316 steel specimens strained at elevated temperatures in air and vacuum has been systematically investigated. It is found that both temperature and environment play an important role in determining the mechanical properties of the coated 316 steel specimens strained at elevated temperatures. And the quantitative changes of surface roughness of coatings before and after straining correspond to the mechanical properties of the 316 steel substrate.

关键词： type 316 steel arc spray high velocity arc spray coating tensile property

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.j. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli M.j. Addison j. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.N. Agaras j. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi j. Albert P. Albicocco G.L. Albouy S. Alderweireldt M. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali H.M.j. Ali S. Ali S.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke j.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen j.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki j.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.j. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena j-F. Arguin S. Argyropoulos j.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai N.A. Asbah j. Assahsah K. Assamagan R. Astalos S. Atashi R.j. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.j. Bailey V.R. Bailey j.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas j. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-S. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAS Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as Standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced background.This paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS experiment.Two taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet pseudorapidity.Differences in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS jET QUARK GLUON TAGGING

Research on the Influence of Steam Curing on Properties of C50 Shield Segment Concrete

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武汉理工大学学报 2010年第17期32卷 137-140页

作者： li j H Wuhan Harbour Engineering Design & Research Co. Ltd.Wuhan 430071China Key Lab of Large-span Bridge Construction Technology Ministry of CommunicationsWuhan 430071China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The effects of steam curing on mechanical properties,drying shrinkage,cracking sensitivity,anti-permeability,and carbonation resistance of C50 shield segment concrete were investigated,which were compared with the standard curing conditions. The results indicated that steam curing could increase early strength of concrete and reduce its drying shrinkage. However,steam curing reduced later strength of concrete,increased its crack sensitivity and deteriorated its anti-permeability and carbonation resistance. Moreover,the incorporation of fly ash could improve the durability of steam-cured concrete.

关键词： shield segment concrete steam curing properties influence

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球形聚焦测井的数值模拟

国外测井技术 1993年第3期8卷 28-32页

作者： li,j 李艳婷

γ"variant-sensitive deformation behaviour of Inconel 718 superalloy

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journal of Materials Science & Technology 2022年第31期126卷 169-181页

作者： R.Y.Zhang H.L.Qin Z.N.Bi Y.T.Tang j.Araújo de Oliveira T.L.Lee C.Panwisawas S.Y.Zhang j.Zhang j.li H.B.Dong Centre of Excellence for Advanced Materials Dongguan 523808China School of Engineering University of LeicesterUniversity RoadLeicester LE17RHUnited Kingdom Beijing Key Laboratory of Advanced High Temperature Materials Central Iron and Steel Research InstituteBeijing 100081China Department of Materials University of OxfordParks RoadOxford OX13PHUnited Kingdom StressMap Engineering and Innovation DepartmentThe Open UniversityWalton HallMilton Keynes MK76AAUnited Kingdom ISIS Neutron Source Rutherford Appleton LaboratoryHarwell Science and Innovation CampusChiltonOxfordshire OX110QXUnited Kingdom School of Material Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Strengthening in Inconel 718 superalloy is derived from dislocation interaction withγ"precipitates,which exist in disk-shaped three possible orientation variants with their{100}habit plane normal to each other.The interactions between dislocations andγ"precipitates vary according to theγ"orienta-tion variants,which makes the deformation behaviour complicated and difficult to reveal experimentally.In this work,γ"variant distributions of Inconel 718 samples were tailored by ageing heat treatment under either tensile or compressive stress.Theγ"variant-sensitive deformation behaviours were then studied by in situ tensile tests via neutron diffraction at room temperature.It is demonstrated that yield-ing first takes place in grains oriented withparallel to the loading direction.An identical lattice strain response to applied stress of both theγmatrix and theγ"precipitates was observed during yield-ing,suggesting that dislocations shearing through theγ"precipitates is predominant at this stage.Vari-ations in yield strength for samples with differentγ"variant distributions were observed,which can be attributed to different strengthening that arises from interactions between dislocation and differentγ"variants.

关键词： Ni-base superalloys Precipitation strengthening Neutron diffraction Lattice strains Plastic deformation

Statistical downscaling model for late-winter rainfall over Southwest China

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Science China Earth Sciences 2015年第7期58卷 1827-1839页

作者： RUAN ChengQing li jianPing FENG juan State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University joint Center for Global Change Studies

A statistical downscaling model is built for the late-winter rainfall over Southwest China(SWC).A partial-correlation method is used for selecting factors.The results show that the selected factors for late-winter rainfall in SWC are sea level pressure in Western Europe(SNAO)and sea surface temperature in Western Pacific(WPT).SNAO is related to the southern pole of North Atlantic Oscillation(NAO)and excites Southern Eurasian teleconnection,which influences the development of the southern branch trough and the water vapor transport to SWC.WPT indicates the variability of ENSO in the tropical Western Pacific.WPT excites Pacific-East Asia teleconnection and an anticyclone(cyclone)is formed in the southern part of China and suppresses(enhances)rainfall over SWC.A regression statistical downscaling model using SNAO and WPT shows good performance in fitting the variability of late-winter rainfall in the whole SWC region and every observation station,and the model also shows strong robustness in the independent validation.The statistical model can be used for downscaling output from seasonal forecast numerical models and improve the SWC late winter rainfall prediction in the future.

关键词：回归统计降水预报中国西南降尺度模型热带西太平洋中国南方 SWC

Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao li Tianyu ZHENG Weiyang QIN Ruilan TIAN Hu DING j.C.jI liqun CHEN Department of Engineering Mechanics North University of ChinaTaiyuan 030051China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and crosswind.Scavenging the combined energy of vibration and wind with a single energy harvesting structure is fascinating.For this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy envelope.The results of the analytical prediction are verified with the Monte-Carlo method(MCM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base excitation.However,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed wind.Relevant experiments are conducted to investigate the validity of the theoretical prediction and numerical simulation.The experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind speeds.However,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

Association of N-terminal pro-brain natriuretic peptide with the severity of coronary artery disease in patients with normal left ventricular ejection fraction

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Chinese Medical journal 2014年第4期127卷 627-632页

作者： Wu NQ Guo YL li XL liu j Qing P Xu RX Zhu CG jia Y j liu G Dong Q jiang LX li j j Ma FL Division of Dyslipidemia State Key Laboratory of Cardiovascular Disease Fu Wai Hospital National Center for Cardiovascular Disease Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China Department of Cardiology First Hospital of Hohhot Hohhot Inner Mongolia 010030 China

Backround N-terminal pro-brain natriuretic peptide （NT-proBNP） is a reliable predictor in acute coronary artery disease （CAD）. little is known about patients with stable CAD, especially Chinese patients with CAD. The aim of the present study was to investigate the association of NT-proBNP levels with the severity of CAD in patients with normal left ventricular ejection fraction. Methods A total of 658 consecutive patients were divided into two groups based on angiograms： CAD group （n=484） and angiographic normal control group （n=174）. The severity of CAD was evaluated by modified Gensini score, and its relationship with NT-proBNP was analyzed. Results The prevalence of risk factors such as age, male gender, diabetes mellitus （DM）, dyslipidemia, smoking, and family history of CAD in the CAD group were higher than that in the control group. In multivariate regression model analysis, age, gender, and DM were determinants of the presence of CAD. NT-pro BNP was found to be an independent predictor for CAD （OR：1.66 （95% CI： 1.06-2.61）, P 〈0.05）. In a receiver operating characteristic （ROC）curve analysis, an NT-proBNP value of 641.15 pmol/L was identified as a cut-off value in the diagnosis or exclusion of CAD （area under curve （AUC）=0.56, 95% CI： 0.51-0.61）. Furthermore, NT-proBNP was positively correlated with Gensini score （r=0.14, P 〈0.001） in patients with CAD. Conclusion NT-proBNP was an independent predictor for Chinese patients with CAD, suggesting that the NT-proBNP level might be associated with the presence and the severity of CAD.

关键词： N-terminal pro-brain natriuretic peptide coronary artery disease risk factors modified Gensini score