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EFFECt OF ELECtRIC FIELD ON tHE AUStENIZAtION OF A LOW CARBON StEEL

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 689-693页

作者： X.t.Liu j.Z.Cui theKeyLaboratoryofElectromagneticProcessingofMaterials MinistryofEducationNortheasternUniversityShenyang110004China

With an electric field during austenitizing, the martensite transformation of the low carbon steel was promoted, and more martensite were obtained. the electric field promotes the homogeneity of carbon, and reduces the free energy of austenite. the critical neuclus r* and the critical driving force G* responsible for the nucleation of proeutectoid ferrite were increased. As a result of which the diffusion controlled proeuctoid ferrite transformation was retarded and the hardenability was improved.

关键词： austenization electric field proeutectoid ferrite hardenability

Enhanced helium ion irradiation tolerance in a Fe-Co-Ni-Cr-Al-ti high-entropy alloy with L12 nanoparticles

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journal of Materials Science & technology 2023年第12期143卷 169-177页

作者： Y.L.Zhao F.L.Meng t.Yang j.H.Luan S.F.Liu G.M.Yeli W.t.Lin W.H.Liu X.j.Liu C.t.Liu j.j.Kai School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China School of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Mechanical Behavior Division of Shenyang National Laboratory for Materials ScienceCity University of Hong KongHong KongChina Department of Mechanical Engineering City University of Hong KongHong KongChina Institute of Nuclear&New Energy technology Tsinghua UniversityBeijing 100084China

L12-strengthened high entropy alloys(HEAs)with excellent room and high-temperature mechanical prop-erties have been proposed as promising candidates as structural materials for advanced nuclear ***,knowledge about their radiation response is fairly *** the present work,a novel HEA with a high density of L12 nanoparticles was irradiated with He ion at 500°*** electron microscope(tEM)and atom probe tomography(APt)were employed to study the evolution of mi-crostructural stability and radiation-induced *** to the single-phase FeCoNiCr HEA,the main microstructural features were numerous large faulted dislocation loops and helium *** the irradiation resistance of the present L12-strengthened HEA is much improved in terms of reduced bubble size,which could be attributed to the considerable He trapping efficiency of the coherent pre-cipitate/matrix interface and the enhanced capability of the interface for damage elimination when the matrix channel width is *** analysis revealed that an inverse-Kirkendall-mechanism-dominated radiation-induced segregation(RIS)occurs around bubbles,where a significant Co enrichment and Ni de-pletion can be clearly *** addition,the competing dynamics of ballistic mixing and elemental clustering that raised from the irradiation-enhanced diffusion in a highly supersaturated matrix,along with the low precipitation nucleation barrier due to the small lattice misfit,lead to a dynamical pre-cipitation dissolution and re-precipitation appears under *** a promising phenomenon is expected to promote a potential self-healing effect and could in turn provide a sustainable irradiation tolerance over the operational lifetime of a reactor.

关键词： L12 nanoparticles High-entropy alloy Helium bubble Phase stability Radiation-induced segregation

In-port-plug transmission line design of the ItER plasma position reflectometer

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Plasma Science and technology 2020年第6期22卷 15-20页

作者： j MARtÍNEZ-FERNÁNDEZ ÁCAPPA A SIMONEttO t EStRADA E DE LA LUNA E j BLANCO Laboratorio Nacional de Fusión.CIEMAt Avda Complutense 40.Madrid 28040Spain CNR-IStP via Cozzi 5320125 MilanoItaly

this work describes the microwave design of the transmission line housed in the in-port-plug region of the ItER plasma position reflectometer(PPR).the design of the components of the inport-plug reflectometers(located in equatorial port-plug 10(EPP10) and in upper-port-plug 01(UPP01)) is *** a 3 D ray tracing code, the spatial position and optimum orientation angles of each set of emission and detection antennas were determined.A feasible path was then created from the obtained antenna positions and orientations to the primary vacuum *** tall waveguides were chosen to reduce ohmic *** to space constraints in the ItER crowded environment, bends in oversized waveguides were unavoidable, and thus mode conversion was *** keep mode conversion losses at bay, hyperbolic secant curvature bends had to be used whenever ***, E-plane bends in tall waveguides proved to be especially critical, making it necessary to employ other approaches when higher bending angles were *** conversion results were obtained by evaluating the mode coupling *** losses have also been computed and their results compared with commercial simulators, obtaining a perfect agreement.

关键词： reflectometry microwave technology ItER diagnostic

Lysozyme as an alternative to growth promoting antibiotics in swine production

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journal of Animal Science and Biotechnology 2016年第1期7卷 34-40页

作者： W. t. Oliver j.E.Wells USDA ARS U.S. Meat Animal Research Center P. O. Box 166 Clay Center NE68933-0166 USA

Lysozyme is a naturally occurring enzyme found in bodily secretions such as tears, saliva, and milk. It functions as an antimicrobial agent by cleaving the peptidoglycan component of bacterial cell walls, which leads to cell death. Antibiotics are also antimicrobials and have been fed at subtherapeutic levels to swine as growth promoters. these compounds benefit swine producers by minimizing production losses by increasing feed efficiency and decreasing susceptibility to bacterial infection and disease. this manuscript reviews the knowledge of the effects of lysozyme, as compared to traditional subtherapeutic antibiotics in swine feed, on pig performance and health. It is clear from decades of studies that antibiotic use in feeds increases pig performance, particularly in the nursery. Similarly, lysozyme, as a feed additive, increases growth and feed efficiency. While the mechanism by which antibiotics and lysozyme improve performance is not clearly understood, both of these feed additives improve gastrointestinal health, improve the metabolic profile, and alter the gastrointestinal bacteria ecology of swine. therefore, lysozyme is a suitable alternative to growth-promoting subtherapeutic antibiotic use in swine feed.

关键词： Antibiotics Gastrointestinal Lysozyme Microbiota Review Swine

Multi-Physics Analyses of Selected Civil Engineering Concrete Structures

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Communications in Computational Physics 2012年第8期12卷 885-918页

作者： j.Kruis t.Koudelka t.Krejcí Department of Mechanics Faculty of Civil EngineeringCzech Technical UniversityThákurova 7Prague16629Czech Republic

this paper summarizes suitable material models for creep and damage of concrete which are coupled with heat and moisture *** fully coupled approach or the staggered coupling is *** equations are spatially discretized by the finite element method and the temporal discretization is done by the generalized trapezoidal *** of non-linear algebraic equations are solved by the Newton *** of an efficient and extensible computer code based on the C++programming language is ***,successful analyses of two real engineering problems are described.

关键词： Coupled problems heat and moisture transfer creep damage mechanics hydrothermo-mechanical analysis efficient solvers analysis of containment watertightness of foundation slabs

Simplified design of rock cavern concrete lining to resist shock loading

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journal of Central South University 2010年第5期17卷 1087-1094页

作者： ZHAO P j LOK t S 殷志强周子龙 Butler Partners Pty Ltd Queensland 4006 Australia Protective technology Research Centre School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 Singapore School of Resources and Safety Engineering Central South University Changsha 410083 China

A simplified method was proposed for the design of concrete lining in underground rock cavern/tunnel against shock loading. the loading may result from the detonation of explosives on ground surface or ground penetration projectiles exploding adjacent to the cavern/tunnel. the resulting problem necessitates the solution of the dynamics of a beam loaded by a transient pressure uniformly distributed over the span. According to mechanical characteristics of the system with rock bolt and shotcrete, a dynamic support design method based on equivalent single degree of freedom （SDOF） was put forward. the SDOF method was applied to obtaining the maximum displacement at the mid-span of the beam, which is often the controlling factor in the blast-resistant design. In the formulation of the problem, the proposed method combines the phenomena of spalling and structural dynamics theory. An example is provided to demonstrate the applicability of this simplified method.

关键词： tunnel lining design shock loading dynamic response rock cavern

Power management unit chip design for automobile active-matrix organic light-emitting diode display module

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journal of Central South University 2009年第4期16卷 621-628页

作者： KIM j H PARK j H KIM j H CAO t V LEE t Y BAN H j YANG K KIM H G HA P B KIM Y H Department of Electronic Engineering Changwon National University 9 Sarim-Dong Changwon 641-773 Korea Denso PS Electronics Corporation 47 Seongsan-Dong Changwon 641-315 Korea

A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. the PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. the driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.

关键词： DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage

Growth of small diameter multi-walled carbon nanotubes by arc discharge process

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Chinese Physics B 2014年第3期23卷 412-417页

作者： K.t.Chaudhary j.Ali P.P.Yupapin Institute of Advanced Photonics Science (APSI) Nanotechnology Research Alliance Universiti Teknologi Malaysia 81310Johor Bahru Malaysia Nanoscale Science and Research Alliance (N’SERA) Faculty of Science King Mongkut’s Institute of Technology Ladkrabang

Multi-walled carbon nanotubes （MWCNts） are grown by arc discharge method in a controlled methane environment. the arc discharge is produced between two graphite electrodes at the ambient pressures of 100 tort, 300 torr, and 500 torr. Arc plasma parameters such as temperature and density are estimated to investigate the influences of the ambient pressure and the contributions of the ambient pressure to the growth and the structure of the nanotubes. the plasma temperature and density are observed to increase with the increase in the methane ambient pressure. the samples of MWCNt synthesized at different ambient pressures are analyzed using transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. An increase in the growth of MWCNt and a decrease in the inner tube diameter are observed with the increase in the methane ambient pressure.

关键词： electric discharge arc plasma temperature and density carbon nanotubes

In vitro evaluation of 3D printed polycaprolactone scaffolds with angle-ply architecture for annulus fibrosus tissue engineering

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Regenerative Biomaterials 2019年第3期6卷 175-184页

作者： t.R.Christiani E.Baroncini j.Stanzione A.j.Vernengo Department of Biomedical Engineering Department of Chemical Engineering Rowan University201 Mullica Hill RoadGlassboroNJ 08028USA

tissue engineering of the annulus fibrosus(AF)is currently being investigated as a treatment for intervertebral disc degeneration,a condition frequently associated with low back *** objective of this work was to use 3D printing to generate a novel scaffold for AF repair that mimics the structural and biomechanical properties of the native ***-layer scaffolds were fabricated by depositing polycaprolactone struts in opposing angular orientations,replicating the angle-ply arrangement of the native AF *** were printed with varied strut diameter and *** constructs were characterized morphologically and by static and dynamic mechanical *** surfaces were etched with unidirectional grooves and the influence on bovine AF cell metabolic activity,alignment,morphology and protein expression was studied in ***,the axial compressive and circumferential tensile properties of the scaffolds were found to be in a similar range to the native AF *** microscopy images indicated that cells were able to attach and spread on the smooth polycaprolactone scaffolds,but the surface texture induced cellular alignment and ***,immunofluorescence analysis demonstrated the aligned deposition of collagen type I,aggrecan and the AF-specific protein marker tenomodulin on the etched ***,results demonstrated the potential for using the scaffolds as a template for AF regeneration.

关键词： surface modification scaffolds materials structure 3D printing