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Computer Modeling in Engineering & sciences 2021年第12期129卷 1125-1150页

作者： s.Morganti f.fahrendorf L.De Lorenzis j.A.Evans T.j.R.Hughes A.Reali Department of Electrical Computer and Biomedical EngineeringUniversita degli Studi di PaviaPavia27100Italy Institute of Applied Mechanics Technische Universitat BraunschweigBraunschweig38106Germany Department of Mechanical and Process Engineering Zurich8092Switzerland Department of Aerospace Engineering sciences University of Colorado BoulderColorado80309USA Institute for Computational Engineering and sciences The University of Texas at AustinTexas78712USA Department of Civil Engineering and Architecture Universita degli Studi di PaviaPavia27100Italy

We investigate primal and mixed u−p isogeometric collocation methods for application to nearly-incompressible isotropic *** primal method employs Navier’s equations in terms of the displacement unknowns,and the mixed method employs both displacement and pressure *** benchmarks for what might be considered acceptable accuracy,we employ constant-pressure Abaqus finite elements that are widely used in engineering *** a basis of comparisons,we present results for compressible *** the methods were completely satisfactory for the compressible ***,results for low-degree primal methods exhibited displacement locking and in general deteriorated in the nearly-incompressible *** results for the mixed methods behaved very well for two of the problems we studied,achieving levels of accuracy very similar to those for the compressible *** third problem,which we consider a“torture test”presented a more complex story for the mixed methods in the nearly-incompressible case.

关键词： Isogeometric analysis isogeometric collocation nearly-incompressible elasticity

Exploring water and ion transport process at silicone/copper interfaces using in-situ electrochemical and Kelvin probe approaches

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journal of Materials science & Technology 2021年第5期64卷 203-213页

作者： B.Munirathinam j.P.B.van Dam A.Herrmann W.D.van Driel f.De Buyl s.j.f.Erich L.G.j.van der Ven O.C.G.Adan j.M.C.Mol Delft University of Technology Department of Materials Science and Engineering DepartmentDelftThe Netherlands Eindhoven University of Technology Department of Applied PhysicsEindhovenThe Netherlands signify High Tech CampusEindhovenThe Netherlands Delft University of Technology Electronic ComponentsTechnology and MaterialsFaculty of Electrical EngineeringDelftThe Netherlands Dow silicones Belgium s.p.r.l. Belgium

In general,packaging materials which encapsulate light emitting diodes(LEDs)and microelectronic devices offer barrier protection against several environmental hazards such as water and ionic ***,these encapsulants may provide pathways for water and ionic contaminants to reach the metal/polymer interfaces and provoke local corrosion of electronics,which is a major reliability concern for polymer encapsulated LEDs and *** the water and corrosive constituents play a crucial role in their reliability,water uptake kinetics,interfacial ion transport and delamination behaviour of silicone coated copper model system,mimicking a typical microelectronics packaging system,is explored in the present *** impedance spectroscopy(EIs)integrated with attenuated total reflection fourier transform infrared(ATR-fTIR)spectroscopy studies revealed that water diffusion inside the silicone network is fickian in nature and the evolution of the observed time constants are related to the diffusion and interfacial reactions.A decrease of impedance magnitude with time was observed in EIs measurements concurrently with water absorption bands shifting towards lower wavenumber in ATR-fTIR measurements,implying the growth of strong hydrogen bonding between water molecules and the silicone *** estimated diffusion constant of water using the capacitance method was in the order of 7×10^(-12)m^(2)s^(-1)and the water absorption volume fraction was in the range of 0%to 0.30%.scanning Kelvin probe studies elucidated the ion transport process occurring at the silicone/copper interface in a humid *** interfacial ion transport process is controlled by the interfacial electrochemical reactions at the cathodic delamination front and the estimated average delamination rate is 0.43 mm h^(-1/2).This work demonstrates that exploring ion and water transport in the silicone coating and along the silicone/copper interface is of pivotal importance as

关键词： silicone Impedance Water transport scanning Kelvin probe Delamination

RECIPROCATING EXTRUsION Of IN sITU Mg_2si REINfORCED Mg-Al BAsED COMPOsITE

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Acta Metallurgica sinica(English Letters) 2008年第3期21卷 169-177页

作者： Z.M. Zhang C.j. Xu X.f. Guo s.Z. jia school of Materials science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 China

M92si reinforced Mg-Al based composite with high amount o/silicon was prepared by permanent mould casting, and then extruded by reciprocating extrusion （RE） after the composite was processed by homogenization heat treatment. The effect of RE processing on the morphology and size of M92si and the mechanical properties of the com- posite were investigated, to develop new ways to refine the M928i phase and improve its shape. The result showed that RE was very useful in refining the M92si phase. The more the RE processing passes, the better the refining effect would be. Moreover, the uniform distribution of M928i phases would be more in the composite. After the composite was processed by RE for 12 passes, most M92si phases were equiaxed, with granular diameter below 20 μm, and distributed uniformly in the matrix of the composite. The mechanical properties of the composite could be increased prominently by RE processing, and were much higher than that in the as-cast state. As the temperature rises, the tensile strength is reduced. for the composite RE processed for 12 passes, the tensile strength, yield strength, and elongation are 325.9 MPa, 211.4 MPa, and 3.3% at room temperature, whereas, 288.2 MPa, ,207.7 MPa, and 7.8%, respectively, at 150℃. In comparison with the properties at room temperature, the tensile strength and yield strength are high and only decrease by 11.6% and 1.8% at 150℃. The M928i reinforced Mg-Al based composite possesses good heat resistance at 150℃. The excellent resistance to effect of heat is attributed to the high melting tempera- ture and good thermal stability of fine Mg2si phases, which are distributed uniformly in the composite, and effectively hinder the grain boundary gliding and dislocation movement.

关键词： Reciprocating extrusion Magnesium alloy In situ composite Elevated temperature property

shock compression and spallation damage of high-entropy alloy Al_(0.1)CoCrfeNi

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journal of Materials science & Technology 2022年第33期128卷 1-9页

作者： N.B.Zhang j.Xu Z.D.feng Y.f.sun j.Y.Huang X.j.Zhao X.H.Yao s.Chen L.Lu s.N.Luo Key Laboratory of Advanced Technologies of Materials Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China The Peac Institute of Multiscale sciences Chengdu 610031China Department of Engineering Mechanics South China University of TechnologyGuangzhou 510641China

shock compression and spallation damage of a face-center cubic phase high-entropy alloy(HEA)Al_(0.1)CoCrfeNi were investigated via plate impact experiments along with free surface velocity *** samples were characterized with transmission electron microscopy and electron backscatter *** Hugoniot equation of state and spall strength at different impact strengths were *** exists a power-law relation between spall strength and strain *** spall strength of Al_(0.1)CoCrfeNi HEA is about 50%higher than those of previously studied HEAs and comparable to those widely applied structural stainless steels at the same shock *** glide and stacking faults are the important deformation mechanisms in the Al_(0.1)CoCrfeNi *** are only observed at high shock *** in the Al_(0.1)CoCrfeNi HEA is ductile in *** are nucleated preferentially in grain interiors,and the intragranular voids show a strong dependence on grain boundary misorientation and peak stress.

关键词： Al_(0.1)CoCrfeNi High-entropy alloy Hugoniot spall damage Microstructure

Giant Magnetoresistance and Microstructure of Melt-spun Cu_(70)Co_(30) Ribbons

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Chinese Physics Letters 1997年第2期14卷 148-150页

作者： sONG Xiao-ping s.W.Mahon R.f.Cochrane B.j.Hickey M.A.Howson school of Materials and Department of Physics University of LeedsLeeds LS29JTUK school of Materials Xi'an Jiaotong UniversityXi'an 710049

This paper reports an investigation on the giant magnetoresistance and microstructure evolution in melt-spun Cu_(70)Co_(30) *** results show that the phase separation is inevitable in the course of quenching,leading to the formation of two types of fcc magnetic Co-rich particles but these do not appear to contribute to the magnetoresistance(MR).On annealing,a very fine distribution of Co-rich precipitates forms at temperatures above 573 K which are responsible for the high MR developed in this material.

关键词： alloy. Microstructure resistance

EffECTs Of HIGH TEMPERATURE PRETREATMENTs ON HIGH TEMPERATURE fRACTURE BEHAVIOR Of siC-C/siC

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Acta Metallurgica sinica(English Letters) 2004年第4期17卷 482-486页

作者： X.G.Luan L.f.Cheng s.R.Qiao j.Zhang Laboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072China

The samples made from a siC-C/siC composite were pretreated in AT under creep, fatigue, creep and fatigue interaction, as well as in dry oxygen and wet oxygen under fatigue at 1300℃for 15 hours. The fracture behaviors of the pretreated samples were investigated at 1300℃. The loading-strain curves and the microstructures of the sample were compared with each other. The various of high temperature tensile behaviors was attributed to the different microstructures resulted from different high temperature pretreatments.

关键词： C/siC high temperature tensile behavior fatigue creep

Genomic selection in plant breeding:Key factors shaping two decades of progress

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Molecular Plant 2024年第4期17卷 552-578页

作者： Admas Alemu johanna Astrand Osval A.Montesinos-López julio Isidro y sanchez javier fernandez-Gónzalez Wuletaw Tadesse Ramesh R.Vetukuri Anders s.Carlsson Alf Ceplitis joséCrossa Rodomiro Ortiz Aakash Chawade Department of Plant Breeding Swedish University of Agricultural SciencesAlnarpSweden Lantmannen Lantbruk SvalövSweden facultad de Telematica University de ColimaColimaColima 28040Mexico Centro de Biotecnología y Genómica de Plantas(CBGP UPM-INIA)Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA)Campus de Montegancedo-UPM28223 MadridSpain International Center for Agricultural Research in the Dry Areas(ICARDA) RabatMorocco International Maize and Wheat Improvement Center(CIMMYT) Km 45Carretera México-VeracruzTexcocoMéxico 52640Mexico

Genomic selection,the application of genomic prediction(GP)models to select candidate individuals,has significantly advanced in the past two decades,effectively accelerating genetic gains in plant *** article provides a holistic overview of key factors that have influenced GP in plant breeding during this *** delved into the pivotal roles of training population size and genetic diversity,and their relationship with the breeding population,in determining GP *** emphasis was placed on optimizing training population *** explored its benefits and the associated diminishing returns beyond an optimum *** was done while considering the balance between resource allocation and maximizing prediction accuracy through current optimization *** density and distribution of single-nucleotide polymorphisms,level of linkage disequilibrium,genetic complexity,trait heritability,statistical machine-learning methods,and non-additive effects are the other vital *** wheat,maize,and potato as examples,we summarize the effect of these factors on the accuracy of GP for various *** search for high accuracy in GP—theoretically reaching one when using the Pearson’s correlation as a metric—is an active research area as yet far from optimal for various *** hypothesize that with ultra-high sizes of genotypic and phenotypic datasets,effective training population optimization methods and support from other omics approaches(transcriptomics,metabolomics and proteomics)coupled with deep-learning algorithms could overcome the boundaries of current limitations to achieve the highest possible prediction accuracy,making genomic selection an effective tool in plant breeding.

关键词： genomic selection genetic gain genomic prediction optimization deep learning training population optimization

基于RsV预融合f蛋白的母体疫苗-早产和其他结局

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中国临床药理学杂志 2024年第9期40卷 1330-1330页

作者： DIEUssAERT I KIM j H LUIK s 王超群

妊娠期间接种呼吸道合胞病毒(RsV)疫苗可以保护婴儿免受RsV疾病的侵害。因此需要一种基于RsV预融合f蛋白的候选母源疫苗(RsVPref3-Mat)的有效性和安全性数据。研究进行了一项涉及18~49岁孕妇的3期试验,以评估RsVPref3-Mat的有效性和安... 详细信息

妊娠期间接种呼吸道合胞病毒(RsV)疫苗可以保护婴儿免受RsV疾病的侵害。因此需要一种基于RsV预融合f蛋白的候选母源疫苗(RsVPref3-Mat)的有效性和安全性数据。研究进行了一项涉及18~49岁孕妇的3期试验,以评估RsVPref3-Mat的有效性和安全性。这些妇女在妊娠24周0天至34周0天以2:1的比例随机分配接受RsVPref3-Mat或安慰剂。主要结局是出生至6个月龄婴儿出现任何或严重医学评估的RsV相关下呼吸道疾病,以及出生至12个月龄婴儿的安全性。

关键词：下呼吸道疾病有效性和安全性安慰剂 f蛋白随机分配 RsV 疫苗妊娠期间

Analysis of Heat Transfer Phenomenon in Magnetohydrodynamic Casson fluid flow Through Cattaneo–Christov Heat Diffusion Theory

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Communications in Theoretical Physics 2017年第7期67卷 91-95页

作者： G. K. Ramesh j. Gireesha, s. A. shehzad, f. M. Abbasi Department of Mathematics School of Engineering Presidency University Bengaluru-560089 Karnataka India Department of studies and Research in Mathematics Kuvempu University Shankaraghatta-577451 Shimoga Karnataka India Department of Mathematics COMSATS Institute of Information Technology Sahiwal-57000 Pakistan Department of Mathematics COMSATS Institute of Information Technology Islamabad-44000 Pakistan

Heat transport phenomenon of two-dimensional magnetohydrodynamie Casson fluid flow by employing Cattaneo-Christov heat diffusion theory is described in this work. The term of heat absorption/generation is incorporated in the mathematical modeling of present flow problem. The governing mathematical expressions are solved for velocity and temperature profiles using RKf 45 method along with shooting technique. The importance of arising nonlinear quantities namely velocity, temperature, skin-friction and temperature gradient are elaborated via plots. It is explored that the Casson parameter retarded the liquid velocity while it enhances the fluid temperature. fhrther, we noted that temperature and thickness of temperature boundary layer are weaker in case of Cattaneo-Christov heat diffusion model when matched with the profiles obtained for fourier＇s theory of heat flux.

关键词： Hydromagnetic flow Casson fluid heat transfer Cattaneo-Christov heat diffusion model numer-ical solution

fE sIMULATION Of CENTER CRACK OCCURRENCE IN TUBE ROUNDs DURING TWO-ROLL ROTARY ROLLING PROCEss

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Acta Metallurgica sinica(English Letters) 2007年第3期20卷 225-234页

作者： s.Z. Li j. Xu Y.D. Yin j.G. Xue f. Pan j.M. Zheng j.H. Yoon Department of Materials forming and Control Engineering Anhui University of Technology Ma＇anshan 243002 China Provincial Key Laboratory of Metals and Processing Ma＇anshan 243002 China steel Tube ＆ Pipe Company of Bao steel Co. Ltd. Shanghai 200941 China Department of Metallurgy and Materials science Changwon National University Changwon 641-773 Korea

With the aid of fE （finite element） code *** 2005, 2-D coupled thermo-mechanical simulation of center-crack occurrence in round billet during 2-roll rotary rolling process was presented using Oyane ductile fracture criteria. A simple modeling is put forward based on the spiral motion of the workpiece as an essential characteristic in movement. The influence of the feed angle and the entry cone angle of the main roll on the process was taken into account in the modeling. The soundness for simplifying the 3-D rotary rolling into a 2-D problem was discussed. By adopting the parameters of Diescher piercer in 140mm mandrel mill of Bao steel, the distribution and development of strain/stress were analyzed, and the eigen value of ductile fracture as well. The critical percentage of diameter reduction was obtained from the simulation. The result showed a good agreement with the experimental value, and therefore was of widely guiding significance to the practical process for rationally formulating the deformation parameters of steel tube piercing.

关键词： numerical simulation inside crack, tube piercing rotary rolling seamless tube deformation