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支架特异性脂肪衰减指数与PCI术后靶血管血运重建相关

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国际医学放射学杂志 2024年第2期 251-252页

作者： F.Xu C.C.Wang Q.Tao J.Zhang m.m.zhao S.W.Shi 潘红利

摘要目的探讨支架特异性血管周围脂肪衰减指数（FAI）在支架植入病人中的临床相关性。方法回顾性纳入162例在支架植入后接受连续冠状动脉CT血管成像

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SPHERICAL mICROSTRUCTURE FORmATION OF THE SEmI-SOLID HIGH CHROmIUm CAST IRON Cr20mo2

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Acta metallurgica Sinica(English Letters) 2004年第1期17卷 77-82页

作者： W.m.mao A.m.zhao X.Y.Zhong University of Science & Technology Beijing Beijing 100083 ChinaUniversity of Science & Technology Beijing Beijing 100083 ChinaUniversity of Science & Technology Beijing Beijing 100083 China

The nondendritic semi-solid slurry preparation of high chromium cast iron Cr20mo2 has been studied in this paper. The experiments show that the proeutectic austenitic particles are more spherical under a larger stirring power condition, even if the stirring time is shorter, while the proeutectic austenitic particles are not very much spherical under a smaller stirring power condition and some proeutectic austenitic dendrites also exist, even if the stirring time is very long. The experiments also show that when stirred for 5-6 minutes under the test condition, the semi-solid slurry with 40vol.%-50vol.% solid fraction and spherical proeutectic austenite in the size of 50-80μm can be obtained.

关键词： high chromium cast iron semi-solid electromagnetic stirring

GRID GENERATION AND NUmERICAL SImULATION OF 2-D RIVER FLOW

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Journal of Hydrodynamics 2001年第2期13卷 50-54页

作者： zhao, m.D. Li, Y.T. Dept. of River Eng. Wuhan Univ. Wuhan 430072 China

This paper presents new weighting functions in grid generation and new discretizing scheme of momentum equations in numerical simulation of river flow. By using the new weighting functions, the curvilinear grid could be concentrated as desired near the assigned points or lines in physical plane. By using the new discretizing scheme, the difficulties caused by movable boundary and dry riverbed can be overcome. As an application, the flow in the Wuhan Section of Yangtze River is simulated. The computational results are in good agreement with the measured results. The new method is applicable to the numerical simulation of 2-D river flow with irregular region and moveable boundary.

关键词： Computer simulation Flow of fluids mathematical models Poisson equation Two dimensional

Number of states with given spin I and isospin T for n fermions in a j orbit

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Chinese Physics C 2022年第11期46卷 195-202页

作者： X.Yin Y.m.zhao Shanghai Key Laboratory of Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

In this study,we investigate formulas of the number of states with a given total spin I and isospin T for n nucleons in a single-j shell denoted by DIT(j,n).Talmi's recursion formulas for the number of states with a given z-axis projection of total spin are generalized by further considering the isospin couplings and are applied to derive explicit formulas of DIT(j,n).

关键词： nuclear structure shell model nuclear spin and isospin

SUPERPLASTICITY IN SiC_w/ZK60 COmPOSITE

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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 217-220页

作者： F.Yan K.Wu m.zhao School of muterials Science and Engineering Harbin Institute of Technology Harbin 150001ChinaSchool of Muterials Science and EngineeringHarbin Institute of Technology Harbin 150001ChinaSchool of Muterials Science and EngineeringHarbin Institute of Technology Harbin 150001China

The superplastic deformation behavior of SiCw/ZK60 composite was investigated at temperatures ranging from 573K to 723K and at initial strain rates ranging from 8.3x10-4s-1 to 8.3x10-2s-1. A maximum elongation of 200% with a m-value of 0.35 was obtained at 613K and a initial strain rate of 1.67x 10-2s-1. The apparent activation energy (98kJ/mol) approximates that for grain boundary diffusion (92kJ/mol) in magnesium. It is proposed that the dominant mechanism of superplastic deformation in the present composite is grain boundary sliding accommodated by diffusional transport, besides, interfacial sliding plays an important role in the superplastic deformation.

关键词： magnesium matrix composite superplasticity apparent activation energy

EFFECT OF SILICON ADDITION ON RECRYSTALLIZATION AND PHASE TRANSFORmATION BEHAVIOR OF HIGH-STRENGTH HOT-ROLLED TRIP STEEL

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Acta metallurgica Sinica(English Letters) 2008年第3期21卷 163-168页

作者： L.J. Zhu D. Wu X.m. zhao College of materials Science and Engineering Jilin University Changchun 130025 China The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang110004 China

Because Si is a noncarbide forming element, a multiphase microstructure consisting of ferrite, bainite, and retained austenite, at room temperature, can be formed by controlling the thermomechanical process strictly. The cooling schedules must be restricted by the formation of pearlite and cementite. In the present article, a new integrated mathematical model for prediction of microstructure evolution during controlled rolling and controlled cooling is developed for a typical kind of low carbon Si-mn TRIP steel, which consists of temperature simulation, recrystallization, and transformation models. The influence of Si contents has been thoroughly investigated. The calculated results indicate that Si retards recrystallization, restrains austenite grain growth as well as accelerates polygonal ferrite transformation.

关键词： TRIP steel Recrystallization Ferrite transformation Bainite transformation Silicon

Nucleon-pair approximation with uncoupled representation

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Chinese Physics C 2021年第5期45卷 129-140页

作者： Y.Lei Y.Lu Y.m.zhao School of National Defense Science and Technology Southwest University of Science and TechnologyMianyang 621010China College of Physics and Engineering Qufu Normal UniversityQufu 273165China Shanghai Key Laboratory of Particle Physics and Cosmology School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

In this paper,we propose an approach to nucleon-pair approximation(NPA)with m-scheme bases,in which the collective nucleon pairs are represented in terms of antisymmetric matrices,and commutations between nucleon pairs are given using a matrix multiplication that avoids angular-momentum couplings and *** the present approach significantly simplifies the NPA ***,it is formulated on the same footing with and without isospin.

关键词： uncoupled representation nucleon-pair approximation formalism computational efficiency

High-Temperature Oxidation Behavior of a Ni-Cr-W-Al Alloy

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Journal of materials Science & Technology 2011年第9期27卷 841-845页

作者： Y.C. ma X.J. zhao m. Gao K. Liu Institute of metal Research Chinese Academy of Sciences Shenyang 110016 China

A study was conducted to examine the isothermal oxidation behavior of a new Ni-Cr-W-AI alloy in air at 1250℃ with different time. Oxidation kinetics was determined from weight-change measurements. The microstructure and composition of the oxide scale were investigated by means of scanning electron microcopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a compact and continuous outer Cr2O3 and NiCr2O4 layer and an inner Al2O3 layer that was in dendrite shape. Oxides scales with good adherence were formed on the surface of the alloy, which made the alloy perform excellent high-temperature oxidation resistance.

关键词： Oxidation kinetics Oxide scale High-temperature oxidation resistance

Stabilization of Traffic Flow Based on the multiple Information of Preceding Cars

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Communications in Computational Physics 2008年第4期3卷 899-912页

作者： D.F.Xie Z.Y.Gao X.m.zhao State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China. Institute of System Science School of Traffic and TransportationBeijing Jiaotong UniversityBeijing 100044China.

To enhance the stability of traffic flow,a new car-following model is proposed by taking into account the support of intelligent transportation system(ITS)information,which includes both the headway and the velocity difference of multiple preceding *** new model is based on the Optimal Velocity(OV)model and its extended *** stability condition of the model is obtained by using the linear stability *** nonlinear analysis,the modified Korteweg-de Vries equation is constructed and solved,and the traffic flow is classified into three types,***,metastable,and *** jam phase can thus be described by the kink-antikink soliton solution for the mKdV *** numerical simulation results show that compared with previous models considering only one of the ITS information,the proposed model can suppress traffic jams more efficiently when both headway and velocity difference of arbitrary preceding cars are taken into *** results of numerical simulation coincide with the theoretical ones.

关键词： Traffic flow car-following model stability analysis ITS information