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SCALING PROPERTIES OF INTERFACES IN CRYSTALS UNDER NONEqUILIBRIUM CONDITIONS

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 415-418页

作者： Shi, D.w. Huang, J.Y. Long, q.w. Inst of Metal Research Chinese Acad of Sciences Shenyang China

An equation of Langevin type was proposed to describe the interface evolution in crystals under nonequilibrium conditions (such as in Cu-Fe or Cu-Co system upon ball milling). The scaling properties (H) of this equation is in good agreement with the Monte Carlo simulations described by Bellon and Averback. In this equation the volume diffusion and interface diffusion are all important and this is consistent with some experimental results.

关键词： Ball milling Binary alloys Crystals Mathematical models Nanostructured materials Surface roughness

Multi-objective optimization of gas metal arc welding parameters and sequences for low-carbon steel (q345D) T-joints

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Journal of Iron and Steel Research International 2017年第5期24卷 544-555页

作者： qing Shao tao Xu Tatsuo Yoshino Nan Song School of Mechanical Science and Engineering Jilin UniversityChangchun 130022JilinChina

q345D high-quality low-carbon steel has been extensively employed in structures with stringent weld- ing quality requirements. A multi-objective optimization of welding stress and deformation was presented to design reasonable values of gas metal arc welding parameters and sequences of q345D T-joints. The optimized factors included continuous variables （welding current （I）, welding voltage （U） ahd welding speed （V）） and discrete variables （welding sequence （S） and welding direc- tion （D））. The concepts of the pointer and stack in Visual Basic （VB） and the interpolation method were introduced to optimize the variables. The optimization objectives included the different combina- tions of the angular distortion and transverse welding stress along the transverse and longitudinal dis- tributions. Based on the design of experiments （DOE） and the polynomial regression （PR） model, the finite element （FE） results of the T-joint were used to establish the mathematical models. The Pareto front and the compromise solutions were obtained by using a multi-objective particle swarm optimization （MOPSO） algorithm. The optimal results were validated by the corresponding results of the FE method, and the error between the FE results and the two-objective results as well as that be-tween the FE results and the three-objective optimization results were less than 17.2% and 21.5%, respectively. The influence and setting regularity of different factors were discussed according to the compromise solutions.

关键词： T-joint welding parameter welding sequence Multi-objective optimization Pareto front Gas metal arc welding q345D

Twisted fiber microfluidics:a cutting-edge approach to 3D spiral devices

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Microsystems & Nanoengineering 2024年第1期10卷 193-202页

作者： Shunsuke Kato Daniel w.Carlson Amy q.Shen Yuanyuan Guo Department of Electrical Information and Physics EngineeringSchool of EngineeringTohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Micro/Bio/Nanofluidics Unit Okinawa Institute of Science and TechnologyOnnaKunigami-gun 904-0495 OkinawaJapan Frontier Research Institute for Interdisciplinary Sciences(FRIS) Tohoku UniversityAoba-kuSendai 980-0845 MiyagiJapan Graduate School of Biomedical Engineering Tohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Department of Physiology Graduate School of MedicineTohoku UniversityAoba-kuSendai 980-8575 MiyagiJapan

The development of 3D spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological *** traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates Dean drag forces,eliminating the necessity for external fields in fluid ***,fabricating 3D spiral microfluidics remains a labor-intensive and costly endeavor,hindering its widespread ***,conventional lithographic methods primarily yield 2D planar devices,thereby limiting the selection of materials and geometrical *** address these challenges,this work introduces a streamlined fabrication method for 3D spiral microfluidic devices,employing rotational force within a miniaturized thermal drawing process,termed as *** innovation allows for rapid prototyping of twisted fiber-based microfluidics featuring versatility in material selection and heightened geometric *** validate the performance of these devices,we combined computational modeling with microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3D flow *** results corroborate the presence of a steady secondary flow,underscoring the effectiveness of our *** 3D spiral microfluidics platform paves the way for exploring intricate microflow dynamics,with promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems.

关键词： thereby straight twisted

SUBCONVERGENCE OF FINITE ELEMENTS AND A SELF-ADAPTIVE ALGORITHM

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维普期刊数据库

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Journal of Computational Mathematics 1996年第4期14卷 336-344页

作者： Zhu q D Lin q 南京大学数力系江苏南京中科院系统科学所北京

Precipitation of multi-type nano-quasicrystals in a Mg-Zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： w.Z.wang X.Z.Zhou L.F.Zhang H.q.Ye Z.q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6Zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-Zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Synthesis and Room Temperature Ferromagnetism of Flower-shaped Mn Doped ZnO Nanostructures

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Journal of Materials Science & Technology 2011年第6期27卷 513-517页

作者： Y.q. Chang P.w. wang R.H. Tang q.L. Sun Y. Long School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Large-scale flower-shaped Mn doped ZnO nanostructures have been grown on silicon substrates by simple thermal evaporation at atmospheric *** flower-shaped nanostructure makes up of many nanorods,which are rooted in one *** of X-ray diffraction,high-resolution transmission electron microscopy and Raman spectra results reveal that the products are of single phase with wurtzite *** mapping results show that no impurity clusters exist in the doped *** photoluminescence spectra demonstrate that many oxygen vacancies exist in the doped materials,and the crystal quality is improved and the content of oxygen vacancies is decreased by annealing *** flower-shaped Mn doped ZnO nanostructures exhibit ferromagnetic ordering above room temperature,and its magnetization is decreased by the annealing treatment,which indicates that the magnetic behavior of the doped materials may be related to the interaction between Mn doping and the oxygen vacancies.

关键词： Mn doped ZnO nanomaterials Ferromagnetism Annealing treatment Chemical vapor deposition

SIMULATION-MEASUREMENT INVERSION OF ENVIRONMENT PARAMETERS DURING wELDING

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 763-767页

作者： J. tao D.q. Li C.L. Fan H.Y. Fang Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024 China State Key Laboratory of Advanced welding Production Technology Harbin Institute of Technology Harbin 150001 China

The manual selection of environment parameters during welding simulation will bring a significant error to the simulation result of welding temperature field. By a combination of finite element method （FEM） and infrared thermography, these environment parameters were inversed mathematically in place of previous manual selection. First, FEM model of the welding process was constructed, and the temperature field was computed with initial environment parameters. Then, a real welding process was conducted and the temperature field was measured by infrared thermography. Last, the simulation and measurement results were compared, and the environment parameters were adjusted continuously with the genetic algorithm （ GA ） until the simulation matched the measurement best. Parameters according to the best-matched simulation results were considered as the most appropriate parameters.

关键词： environment parameters welding temperature field inversion

COUPLED SIMULATION OF 3D ELECTRO-MAGNETO-FLOw FIELD IN HALL-HEROULT CELLS USING FINITE ELEMENT METHOD

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 105-116页

作者： J. Li w. Liu Y.q. Lai q.Y. Li Y.X. Liu School of Metallurgy Science and Engineering Central South University Changsha 410083 China Chemistry Department Guangxi Normal University Guilin 531400 China

Two full 3D steady mathematical models are developed by finite element method （FEM） to calcalate coupled physics fields. the electro-magnetic model is built and solved first and so is the fluid motion model with the acquired electromagnetic force as source body forces in Navier-Stokes equations. Effects caused by the ferromagnetic shell, busbar system around, and open boundary problem as well as inside induced current were considered in terms of the magnetic field. Furthermore, a new modeling method is found to set up solid models and then mesh them entirely with so-called structuralized grids, namely hex-mesh. Examples of 75kA prebaked cell with two kinds of busbar arrangements are presented. Results agree with those disclosed in the literature and confirm that the coupled simulation is valid. It is also concluded that the usage of these models facilitates the consistent analysis of the electric field to magnetic field and then flow motion to the greater extent, local distributions of current density and magnetic flux density are very much dependent on the cell structure, the steel shell is a shield to reduce the magnetic field and flow pattern is two dimensional in the main body of the metal pad.

关键词： coupled simulation electromagnetic field flow field aluminum reduction cell finite element analysis

Breeding Rice lines for physio-functional food through indica‘Zhaxima’×japonica‘Nanjing 46’haploid technique

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Food Production, Processing and Nutrition 2019年第1期1卷 23-34页

作者： q.q.Tian X.Li C.M.Lu X.w.Fang Institute of Food Crops Jiangsu Academy of Agricultural SciencesJiangsu High Quality Rice R&D CenterNanjing BranchChina National Center for Rice ImprovementNanjing 210014China Jiangsu Collaborative Innovation Center for Modern Crop Production Yangzhou 225009China College of Life Science Nanjing Normal UniversityNanjing 210023China

Resistant starch(RS)encompasses those forms of starch which are not accessible to human digestive enzymes and are fermented in the colons producing short chain fatty *** plant materials containing RS are few in the *** this contribution,the culture ability of callus from anthers of F1 plants from,landraces,‘Zhaxima’(Oryza sativa ***,high-RS rice line with 7.705±0.142,g/100 g)×‘Nanjing 46’(Oryza sativa ***,rice variety with RS content(g/100 g)of 0.200±0.001 crosses were studied for obtaining high RS rice *** results showed that when M8 basic induction medium was added with 1.5 mg/L 2,4-D、2 mg/LNAA and 0.3 mg/L KT,the inductivity of callus was high as 32.14%for 21 d after pretreatment at 4°C for 3 d;when MS differentiation basic medium was added with 2 mg/LKT and 3 mg/L ABA,the frequency of regeneration for callus was 50.3%with only a regeneration frequency of 4.55%grown into green *** RS content in the seeds was between those of the two parents and was partially normally distributed,the highest RS contents of the regenerated plants was as high as 7.66±1.197%.This produced an efficient technology for regenerating stable rice lines with high RS and good eating quality using anthers culture.

关键词： Rice(Oryza sativa L.) anther culture regeneration resistant Starch