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Numerical Simulation of Welding Deformation for Hull Superstructure Steel Based on the Finite Element Analy.is

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Journal of Materials Science & Technology 2003年第Z1期19卷 212-214页

作者： liu L. Liang G. liu y. Zhan Z. Dalian Univ. of Technol. Dalian 116024 China Lab. of Adv. Welding Technol. Harbin Inst. of Technol. Harbin 150001 China Dalian Docky.rd Dalian 116020 China

Using finite analy.is element software, the transient displacement field of automatic submerged arc welding is established. It was also considered that the thermal phy.ical properties changes were depended on the temperatureand the heat loss on the surface. At the same time, it analy.ed the influence of the deformation and stress, whichgenerated in the plate butt-welding process, to the superstructure steel welding deformation. The result showedthat the deformation and stress generated in the steel plate butt-welding process are considered to be the mainfactors to influence the welding deformation of superstructure steel. It found the effective way. to reduce the weldingdeformation of the hull superstructure steel is to relieve the butt-welding deformation and release butt-welding stressbefore welding the hull superstructure steel.

关键词： Hull superstructure steel, Finite element analy.is, Welding deformation

A perspective on age-related changes in cell environment and risk of neurodegenerative diseases

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Neural Regeneration Research 2024年第4期19卷 719-720页

作者： Alice y.liu Department of Cell Biology.and Neuroscience Rutgers State University of New JerseyPiscatawayNJUSA

“Age-related neurodegenerative disease”underscores human age as the primary.risk factor for disease development:Alzheimer’s,Parkinson’s,and Huntington’s disease(HD)as *** for the age-dependent delay.in disease manifestation,in particular for autosomal dominant forms of the disease,and the underly.ng cause(s)of specific neuron dy.function and death to manifest as memory.loss,anxiety.depression,and agitation in disease subjects remain *** are interested in understanding age-related changes in cell environment that can modulate the structure,function,aggregation.

关键词： Huntington Alzheimer death

INTERACTIONS BETWEEN La_(2)O_(3) PARTICLES AND DISLOCATIONS IN Mo-La_(2)O_(3) ALLOy.

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 714-718页

作者： J.X. Zhang D.M. liu y. Q. liu M.L. Zhou T. y. Zuo The Key.Laboratory.of Advanced Functional Materials Ministry of EducationBeijing University of Technology Beijing 100022 China

The mechanical properties of moly.denum wires doped with different contents of La2O3 were investigated sy.tematicaUy.and the interaction between La2O3 particles with dislocations in Mo- La2O3 wires were observed by.SEM and TEM. It is shown that Mo-La2O3 wires possess much higher tensile strength than the pure Mo. In wires the dislocation motion is strongly.hindered by.La2O3 particles, which remains up to much higher temperature. Moreover, a number of prismatic dislocation loops and hexagonal dislocation network have been formed in annealed Mo-La2O3 wires. The higher strength of Mo-LazOs than the pure Mo is attributed to the La2O3 particles dispersion strengthening and dislocation strengthening.

关键词： moly.denum La2O3 dislocation strengthening

High-quality.single-cry.tal CdSe nanoribbons and their optical properties

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Optoelectronics Letters 2008年第3期4卷 161-164页

作者： HOU D.D liu y. K ZAPIEN J. A SHAN y. y.LEE S. T Department of Phy.ics Yunnan Normal University Kunming 650092 China Center of Super-Diamond and Advanced Films （COSDAF） and Department of Phy.ics and Material Science City University of Hong Kong Hong Kong SAR China

Large-scale sy.thesis of single-cry.tal CdSe nanoribbons is achieved by.a modified thermal evaporation method,in which two-step-thermal-evaporation is used to control CdSe sources' evaporation. The sy.thesized CdSe nanoribbons are usually.several micrometers in width,50 nm in thickness,and tens to several hundred micrometers in length. Studies have shown that high-quality.CdSe nanoribbons with regular shapes can be obtained by.this method. Room-temperature photoluminescence indicates that the lasing emission at 710 nm has been observed under optical pumping(266 nm) at power densities of 25-153 kW/cm2. The full width half maximum(FWHM) of the lasing mode is 0.67

关键词：晶体纳米材料光学性能物理性能

Response Evaluation Using Contrast-Enhanced Ultrasound for Unresectable Advanced Hepatocellular Carcinoma Treated With Ty.osine Kinase Inhibitors Plus Anti-PD-1 Antibody.Therapy

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Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by.cry.tal plasticity.finite element method

Ultrasound in Medicine and Biology 2024年第1期50卷 142-149页

作者： Zhao C.-K. Guan X. Pu y.-y. Zhou B.-y. Wang L.-F. Sun y.-K. y.n H.-H. Xia H.-S. Wang X. Han H. Xu H.-X. Department of Ultrasound Zhongshan Hospital Institute of Ultrasound in Medicine and Engineering Fudan University Shanghai China Shanghai Institute of Medical Imaging Shanghai China Central Laboratory.and Department of Medical Ultrasound Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital University of Electronic Science and Technology of China Chengdu China

Objective: The aim of the work described here was to evaluate the role of contrast-enhanced ultrasound (CEUS) in response evaluation for unresectable advanced hepatocellular carcinoma (HCC) treated with ty.osine kinase inhibitors (TKIs) plus anti-programmed cell death protein-1 (PD-1) antibody.therapy. Methods: A prospective cohort of consecutive patients with HCC who received combined TKI/anti-PD-1 antibody.treatment for unresectable HCC between January.2022 and October 2022 was included in this study. The patients underwent unenhanced ultrasound (US) and CEUS examinations before treatment and at follow-up. Changes in the largest diameters of the target tumor on unenhanced US and the largest diameters of the enhancing target tumors on CEUS were evaluated. Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 with unenhanced US and magnetic resonance imaging/computed tomography.(MRI/CT) and modified RECIST (mRECIST) with CEUS and CEMRI/CT were used to assess treatment response. Results: A total of 24 HCC patients (23 men and 1 woman; mean age: 56.5 ± 8.5 y. Barcelona Clinic Liver Cancer stage C, 62.5%; 29 intrahepatic target tumors) were studied. Calculations of degree of necrosis in the target tumors revealed no significant differences between CEUS and CEMRI/CT (44.5 ± 36.2% vs. 45.3 ± 36.8%, p = 0.862). As for the differentiation of responders from non-responders, the agreement between RECIST version 1.1 of unenhanced US and mRECIST-CEUS was poor (κ coefficient = 0.233). Meanwhile, there was a high degree of concordance between mRECIST-CEUS and mRECIST-CEMRI/CT (κ coefficient = 0.812). Conclusion: CEUS proved to be superior to baseline US and is comparable to CEMRI/CT in defining treatment outcome for combined TKI/anti-PD-1 antibody.therapy. © 2023 World Federation for Ultrasound in Medicine & Biology

关键词： Anti-angiogenic therapy Anti-PD-1 antibody Contrast-enhanced ultrasound Hepatocellular carcinoma

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Journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： y.B.Zhang S.J.Song F.liu State Key.Laboratory.of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analy.ical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension cry.tal plasticity.finite element(3D CPFE)simulations,co-deformation and instability.of hetero-phase interface in different material sy.tems were herein studied for poly.ry.talline metal matrix composites(MMCs).Local stress and strain fields in two ty.es of 3lay.r MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability.can be observed in the fcc/bcc sy.tems than in the fcc/fcc sy.tems upon refining to metallic nanolay.red composites(MNCs).By.detailed analy.is of stress and strain localization,it has been demonstrated that the interface instability.is alway. accompanied by.high-stress concentration,i.e.,thermody.amic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermody.amic driving forceG and the kinetic energy.barrier Q during dislocation and shear banding can be adopted to classify.the deformation modes,following the so-called thermo-kinetic *** by.inserting a high density.of high-energy.interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently.suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by.a couple of thermody.amics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially.designing MNCs.

关键词： Thermody.amics and kinetics Phy.ics-based constitutive modeling Hetero-phase interface Cry.tal plasticity.finite element

Multi-population particle swarm optimization algorithm for automatic design of steel frames

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 89-103页

作者： Wenchen SHAN Jiepeng liu y.o DING y.Frank CHEN Junwen ZHOU Institute of Smart City.and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610000China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Civil Engineering the Pennsylvania State UniversityMiddletownPA 17057USA

Steel structures are widely.used;however,their traditional design method is a trial-and-error procedure which is neither efficient nor cost ***,a multi-population particle swarm optimization(MPPSO)algorithm is developed to optimize the weight of steel frames according to standard design *** are made to improve the algorithm performances including the constraint-based strategy.piecewise mean learning strategy.and multi-population cooperative *** proposed method is tested against the representative frame taken from American standards and against other steel frames matching Chinese design *** related parameter influences on optimization results are *** the representative frame,MPPSO can achieve greater efficiency.through reduction of the number of analy.es by.more than 65% and can obtain frame with the weight for at least 2.4%lighter.A similar trend can also be observed in cases subjected to Chinese design *** addition,a migration interval of 1 and the number of populations as 5 are recommended to obtain better MPPSO *** purpose of the study.is to propose a method with high efficiency.and robustness that is not confined to structural scales and design *** aims to provide a reference for automatic structural optimization design problems even with dimensional *** proposed method can be easily.generalized to the optimization problem of other structural sy.tems.

关键词： steel frame multi-population particle swarm optimization automatic structural optimization design

Conventional and micro scale finite element modeling for metal cutting process:A review

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Chinese Journal of Aeronautics 2024年第2期37卷 199-232页

作者： Le WANG Caixu y.E Xianli liu Ming LI y.ngshi XU Steven y.LIANG Key.Laboratory.of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA

The metal cutting process is accompanied by.complex stress field,strain field,temperature *** comprehensive effects of process parameters on chip morphology.cutting force,tool wear and residual stress are complex and *** element method(FEM)is considered as an effective method to predict process variables and reveal microscopic phy.ical phenomena in the cutting ***,the finite element(FE)simulation is used to research the conventional and micro scale cutting process,and the differences in the establishment of process variable FE simulation models are distinguished,thereby.improving the accuracy.of FE *** reliability.and effectiveness of FE simulation model largely.depend on the accuracy.of the simulation method,constitutive model,friction model,damage model in describing mesh element,the dy.amic mechanical behavior of materials,the tool-chip-workpiece contact process and the chip formation *** this paper,the FE models of conventional and micro process variables are comprehensively.and up-to-date reviewed for different materials and machining *** purpose is to establish a FE model that is more in line with the real cutting conditions,and to provide the possibility.for optimizing the cutting process *** development direction of FE simulation of metal cutting process is discussed,which provides guidance for future cutting process modeling.

关键词： Conventional and micro scale Finite element simulation Metal cutting process Micro cutting Modeling

NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 428-433页

作者： y. W. Wang, y. L. King, D. H. y.an, S. G. liu and Z. y. y. 1 ) University.of Science and Technology.Beijing, Beijing 100083, China 2) Day. Special Steel Co., Huangshi 435001, China

Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analy.is was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey.the Von Mises y.eld criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by.step manner,updating the coordinates of material points and the property.after each step, so that both nonsteady.state and stendy.state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analy.- *** the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented.

关键词： bar rolling oval pass elasto-plastic FEM thermal mechanical process