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Journal of Materials Science & Technology 2013年第12期29卷 1191-1196页

作者： J.C.Pang G.H.Fan X.P.Cui A.B.li l.Geng z.z.zheng q.W.Wang School of Materials Science and Engineering Harbin Institute of Technology

The Ti3Al matrix composite sheet with a novel quasi-continuous chain reinforcement distribution was prepared by using roll bonding and subsequent reaction annealing with pure Ti and SiCp/Al *** (Ti3AlC t Ti5Si3) reinforcements were produced by in situ reaction of the as-rolled Tie(SiC p/Al) laminated composite sheet after a two-stage annealing treatment including first annealing at 660 C and second annealing at 1250 *** microstructure evolution during the reaction annealing was *** the first reaction annealing,TiAl3was formed,and the SiC particles were pushed together due to the Kirkendall effect,and after the second reaction annealing,Ti3Al,Ti3AlC and Ti5Si3were *** addition,the reinforcement distribution presents a quasi-continuous chain microstructure in Ti3Al matrix composite sheet.

关键词： Composite Intermetallic Fabrication Reaction synthesis

Coarsening Kinetics of a Two Phase Mixture with Highly Disparate Diffusion Mobility

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Communications in Computational Physics 2010年第7期8卷 249-264页

作者： G.Sheng T.Wang q.Du K.G.Wang z.K.liu l.q.Chen Department of Materials Science and Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Materials Science and Engineering Iowa State UniversityAmesIA 50011USA Department of Mathematics Pennsylvania State UniversityUniversity ParkPA 16802USA Physics and Space Science Department Materials Science&Nanotechnology InstituteFlorida Institute of TechnologyMelbourneFL 32901USA

The coarsening kinetics of a two-phase mixture with a large diffusional mobility disparity between the two phases is studied using a variable-mobility Cahn Hilliard *** semi-implicit spectral numerical technique was employed,and a number of interpolation functions are considered for describing the change in diffusion mobility across the interface boundary from one phase to *** coarsening rate of domain size was measured using both structure and pair correlation functions as well as the direct computation of particle sizes in real space for the case that the coarsening phase consists of dispersed *** discovered that the average size(R)versus time(t)follows the R^(10/3)∝t law,in contrast to the conventional lSW theory,R^(3)∝t,and the interface-diffusion dominated two-phase coarsening,R^(4)∝t.

关键词： Coarsening kinetics Cahn-Hilliard equation phase-field method computer simulation

Effects of chemical pressure on diluted magneticsemiconductor(Ba,K)(zn,Mn)_2As_2

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Chinese Physics B 2019年第5期28卷 288-292页

作者： Y Peng S Yu G q zhao W M li J F zhao l P Cao X C Wang q q liu S J zhang R z Yu z Deng X H zhu C q Jin College of Materials Science & Engineering Sichuan University Beijing National laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences Collaborative Innovation Center of quantum Matter

Chemical pressure induced by iso-valent doping has been widely employed to tune physical properties of materials. In this work, we report effects of chemical pressure by substitution of Sb or P into As on a recently discovered diluted magnetic semiconductor(Ba,K)(zn,Mn)_2 As_2, which has the record of reliable Curie temperature of 230 K due to independent charge and spin doping. Sb and P are substituted into As-site to produce negative and positive chemical pressures, respectively.X-ray diffraction results demonstrate the successful chemical solution of dopants. Magnetic properties of both K-underdoped and K-optimal-doped samples are effectively tuned by Sb-and P-doping. The Hall effect measurements do not show decrease in carrier concentrations upon Sb-and P-doping. Impressively, magnetoresistance is significantly improved from7% to 27% by only 10% P-doping, successfully extending potential application of(Ba,K)(zn,Mn)_2 As_2.

关键词： chemical pressure (Ba,K)(zn,Mn)2As2 diluted magnetic semiconductor iso-valent doping

Research on Service life Prediction Model of Concrete Structure of Sea-crossing Bridge

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武汉理工大学学报 2010年第17期32卷 141-146页

作者： WANG C J zHANG G z lIu K X Tu l q lI J H qIN M q zhejiang Province zhoushan Island linking Construction Commanding Department Zhejiang 316032China Wuhan Harbor Engineering Design & Research Institute Co. ltd Wuhan 430071China Key lab of large-span Bridge Construction Technology Ministry of CommunicationWuhan 430071China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

According to the chloride corrosion environment,service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,which was suitable for China. Furthermore,a visual service life prediction program of concrete structure was developed by optimized Monte Carlo method. Meanwhile,life 365 program was compared,indicating reliability of the prediction program. Finally,the validity of prediction model was verified in JinTang Bridge of zhoushan Island Mainland linkage Project.

关键词： sea-crossing bridge concrete structure service life prediction model verify

using Inverter-Based Renewable Generators to Improve the Grid Power quality-A Review

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Chinese Journal of Electrical Engineering 2018年第4期4卷 16-25页

作者： Tao Wang Heng Nian z.q.zhu Department of Electronic and Electrical Engineering University of SheffieldSheffieldS13JDU.K. College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

With the increasing penetration of renewable power in the grid,renewable generators are expected to play more important roles rather than merely working as active power *** the high controllability and considerable idle capacity of the inverter-based renewable generators,various auxiliary functions for them have been studied to benefit the *** these auxiliary functions,the grid power quality improvement is very *** paper presents a review of the emerging control strategies for inverter-based renewable generators to improve grid power *** related papers are classified with different power quality issues and technical routes,and a comprehensive comparison is *** future trends of this research area are also discussed.

关键词： Renewable generator auxiliary function power quality improvement grid voltage harmonic and unbalance

Microstructural Evolution and Service Performance of Cold-drawn Pure Aluminum Conductor Wires

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Journal of Materials Science & Technology 2017年第9期33卷 1039-1043页

作者： X.M.luo z.M.Song M.l.li q.Wang G.P.zhang Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Microstructures and service performance(mechanical and electrical properties) of the commercially pure Al conductor wires subjected to different cold drawing strains were investigated. The results show that the microstructures of the cold-drawn Al wires along the radial direction were inhomogeneous, i.e. the texture in the center region was strong and weak components, while that in the surface region shifted from the initial cubic texture to a component and finally developed into a strong component. The volume fraction of the high angle grain boundaries in the surface region was higher than that in the center region. The cold-drawing process greatly enhanced the yield strength of the pure Al wires while retained the acceptable electrical resistivity. The strengthening mechanism and the variation of electrical conductivity of the cold-drawn Al wires are discussed through correlating with microstructure evolution.

关键词： Cold drawing Aluminum Microstructure Strength Conductivity

Early prediction of severe acute pancreatitis by urinary trypsinogen activation peptide

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Hepatobiliary & Pancreatic Diseases International 2002年第2期1卷 285-289页

作者： liu z.-S. Jiang C.-q. qian q. Sun q. Fan l.-F. Ai z.-l. Department of General Surgery Zhongnan Hospital Wuhan University Wuhan 430071 China

Objective: To investigate the value of urinary trypsi-nogen activation peptide (TAP) in the early predic-tion of severe acute pancreatitis and to compare itwith acute physiology and chronic health evaluationⅡ (APACHE Ⅱ).Methods: We assessed the predictive value of urinaryTAP concentrations measured by a competitive en-zyme-linked immunosorbent assay. urine sampleswere collected for detecting TAP concentrations atadmission, and 24, 48, and 72 h from 41 patientswith acute pancreatitis (12 with severe disease, 29with mild disease) who presented within 48 h the on-set of symptoms and from 11 control patients, whileAPACHE Ⅱ scores were recorded at 48 h after ***: The peak median urinary TAP concentrationwas seen at admission. The median urinary TAPconcentration at admission for severe pancreatitis (95nmol/l) was significantly higher than the medianfor patients with mild pancreatitis (20 nmol/l, P<0. 005) and controls (15 nmol/l, P<0. 005). TAPconcentrations were significantly higher in patientswith severe acute pancreatitis than the median in pa-tients with mild pancreatitis (P<0. 05) and controls(P<0. 05) on days 2 to 3. The median APACHE Ⅱscores of severe patients were significantly differentfrom those of mild patients (10.5 vs 6.0, P<0.01).The sensitivity, specificity, positive predictive, andnegative predictive values of an admission urinaryTAP≥35 nmol/l for severe pancreatitis were91.7%, 89.7%, 78.6% and 96.3%, whereas 48 hafter admission the values for APACHE Ⅱ scores(≥9) were 75.0%, 72.7%, 52.9% and 87.5%. Inprediction of disease severity, the urine TAP concen-tration was much better than APACHE Ⅱ at 48 ***: urinary TAP obtained at the first 48 hof the onset of symptoms can predict severe acutepancreatitis. In prediction of disease severity, theurinary TAP is much better than APACHE Ⅱ score.

关键词： acute pancreatitis trypsinogen activation peptide APACHE Ⅱ

The effect of Co and Cr substitutions for Ni on mechanical properties and plastic deformation mechanism of FeMnCoCrNi high entropy alloys

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Journal of Materials Science & Technology 2020年第13期47卷 146-155页

作者： H.F.zhang H.l.Yan H.Yu z.W.Ji q.M.Hu N.Jia Key laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China State Key lab Rolling&Automat Northeastern UniversityShenyang 110819China Institute of Metal Research Chinese Academy of ScienceShenyang 110016China Shen Yang university of Technology Shenyang 110870China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

The elastic constants,ideal tensile strength(ITS),stacking fault energy(SFE),lattice constant and magnetic moment of FeMnCoCrNi high entropy alloys with varying Co and Cr contents at 0 and 300 K were systematically investigated by first-principle *** the alloys with Co substitution for Ni,at both temperatures the elastic stability of the face-centered cubic(fcc)phase,bulk elastic modulus(B),Young’s modulus(E),shear modulus(G)and ITS increase monotonically with increasing Co ***,the Cauchy pressure(Cp),Pugh ratio(B/G),Poisson ratio(v),zener anisotropy ratio(Az)and elastic anisotropy ratio(AVR)decrease *** SFE also decreases with the increase of Co,resulting in the change of plastic deformation mechanism from dislocation slip to mechanical twinning,and then to hcp-martensitic *** elucidates the underlying mechanism of the effect of Co addition on the strength and micromechanical behavior of FeMnCoCrNi *** with Co,the Cr substitution for Ni leads to the more complex change of elastic constants and *** increase of Cr shows the similar effect on SFE and deformation mechanism as that of *** variation of valence electron concentration and magnetism affect the *** increase of either Co or Cr leads to the reduced magnetic moments of Fe and *** could be responsible for the monotonic decrease of both lattice constant and SFE as the Co content ***,for the Cr addition case,multiple factors may affect the evolution of lattice constant and *** findings shed light on the deformation mechanism of the alloys with different compositions.

关键词： High entropy alloys First-principle calculations Elastic constants Ideal tensile strength Stacking fault energy

Deformation behaviors of as-built and hot isostatically pressed Ti-6Al-4V alloys fabricated via electron beam rapid manufacturing

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Journal of Materials Science & Technology 2019年第11期35卷 2552-2558页

作者： z.liu z.B.zhao J.R.liu l.Wang S.X.zhu G.Yang S.l Gong q.J.Wang R.Yang institute of metal research chinese academy of sciencesshenyang110016china school of materials science and engineering university of science and technology of chinahefei230000china avic manufacturing technology institute beijing100024china

The deformation behavior of as-built and hot isostatically pressed(HIP)Ti-6Al-4V alloys fabricated using electron beam rapid manufacturing(EBRM)were investigated in this *** deformation characteristics were characterized using a laser scanning confocal microscope and electron back-scattered diffraction(EBSD).In the as-built sample,prismatic slip was the main mode of deformation,as well as a small amount of basal slip and *** planar slip lines with large length scales were observed across severalα*** hot isostatical pressing,prismatic and basal slip were the main mode of deformation,accompanied by abundant cross-slip and multiple slip,and most of the slip lines were blocked within an a *** differences in deformation behavior were associated with the coarsening of a laths and the more retained p phase after HIP compared to the as-built *** cross-slip and multiple slip can lead to superior elongation-to-failure and a greater strain hardening effect in the HIP alloy compared to the as-built sample.

关键词： Electron beam rapid manufacturing Ti-6Al-4V Hot isostatic pressure Mechanical properties Slip behavior

Generalized Weighted Morrey Estimates for Marcinkiewicz Integrals with Rough Kernel Associated with Schrodinger Operator and Their Commutators

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 77-98页

作者： Ferit GuRBuz Faculty of Education Department of Mathematics EducationHakkari UniversityHakkari 30000Turkey

let l =-△+V(x) be a Schrodinger operator, where △ is the laplacian on R^n,while nonnegative potential V(x) belonging to the reverse Holder class. The aim of this paper is to give generalized weighted Morrey estimates for the boundedness of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their ***, the boundedness of the commutator operators formed by BMO functions and Marcinkiewicz integrals with rough kernel associated with Schrodinger operators is discussed on the generalized weighted Morrey spaces. As its special cases, the corresponding results of Marcinkiewicz integrals with rough kernel associated with Schrodinger operator and their commutators have been deduced, respectively. Also, Marcinkiewicz integral operators, rough Hardy-littlewood(H-l for short) maximal operators, Bochner-Riesz means and parametric Marcinkiewicz integral operators which satisfy the conditions of our main results can be considered as some examples.

关键词： Marcinkiewicz operator Rough kernel Schrodinger operator generalized weighted Morrey space Commutator BMO