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Refueling for steady-state Plasma by Repetitive Pellet injection in Large Helical Device

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Plasma science and Technology 2004年第3期6卷 2275-2280页

作者： H.yamada R.sakamoto i.Viniar M.Goto K.Kikuchi A.Lukin s.Masuzaki j.Miyazawa s.Morita y.Oda s.sudo K.Tanaka National institute for Fusion science Toki Japan PELiN Laboratory Ltd. Moscow Russia Mitsubishi Heavy industries Ltd. Kobe Japan

A repetitive pellet injector has been developed for investigation ofrefueling issues towards the steady-state operation in Large Helical Device (LHD). Continuousoperation of more than 10000 pellet launching at 10 Hz has been demonstrated. The maximum repeatingrate is 11 Hz. No technical constraint for longer operation has been found. The reliability ofpellet launch has exceeded 99.9%. The initial application to the NBi-heated plasmas has beensuccessful in the last experimental campaign of LHD. Although the pulse length is limited by theoperational constraint of NBi, the plasma with a density of 8 X 10^(19) m^(-3) has been sustainedfor 2 s by the pellet injection at 10 Hz. A prospect for the future experiment is discussed on thebasis of the initial result.

关键词： cryo-cooler screw extruder solid hydrogen

investigating the physics of disruptions with real-time tomography at jET

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Plasma science and Technology 2022年第3期24卷 80-88页

作者： Diogo R FERREiRA Pedro j CARVALHO ivo s CARVALHO Chris i sTUART Peter j LOMAs jET Contributors 无 instituto de Plasmas e Fusão Nuclear(iPFN) Instituto Superior Técnico(IST)Universidade de LisboaAv.Rovisco Pais 11049-001 LisboaPortugal Culham Centre for Fusion Energy(CCFE) UK Atomic Energy Authority(UKAEA)Culham Science CentreAbingdonOX143DB OxfordshireUnited Kingdom see the author list of E.joffrin et al 2019 Nucl Fusion 59112021 EUROfusion Consortium JETCulham Science CentreAbingdonOX143DBUK

As jET is developing and testing operational scenarios for higher fusion performance,an increase in pulse disruptivity is being *** a deeper analysis,we find that several radiative phenomena play an active role in determining the outcome of the *** analysis is enabled by the use of real-time tomography based on the bolometer *** though plasma tomography is an inverse problem,we use machine learning to train a forward model that provides the radiation profile directly,based on a single matrix multiplication *** model is used to investigate radiative phenomena including sawtooth crashes,ELMs and MARFE,and their relationship to the radiated power in different regions of *** particular,we use realtime tomography to monitor the core region,and to throw an alarm whenever core radiation exceeds a certain *** results suggest that this measure alone can anticipate a significant fraction of disruptions in the jET baseline scenario.

关键词： plasma tomography machine learning plasma disruptions

sTUDy OF EXPLOsiVE VAPORiZATiON OF LD11R ALUMiNUMALLOy DURiNG ELECTRON BEAM DEEP PENETRATiON

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Acta Metallurgica sinica(English Letters) 2000年第6期13卷 1119-1124页

作者： Wang, y.j. jia, s.j. Liu, F.j. Chen, X.F. NKL of EDB process. Technol. Beijing 100024 China

High-power-density electron beam with single pulse was performed on the LD11R aluminum alloy. The electron beam was focused on three typical positions. For each case, the distribution of the solute concentration at the cavity bottom solid-liquid interface was investigated by using the 'rapidly fixing' method. The interaction of the beam and solute atoms was analyzed. A new mechanism of explosive vaporization was proposed based on the present results. The occurrence of this explosive vaporization source was discussed.

关键词： Electron beam welding Vaporization

Timoshenko beam model for chiral materials

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Acta Mechanica sinica 2018年第3期34卷 549-560页

作者： T.y.Ma y.N.Wang L.yuan j.s.Wang Q.H.Qin Department of Mechanics Tianjin University school of Engineering Deakin University Research school of Engineering Australian National University

Natural and artificial chiral materials such as deoxyribonucleic acid （DNA）, chromatin fibers, flagellar filaments, chiral nanotubes, and chiral lattice materials widely exist. Due to the chirality of intricately helical or twisted microstructures, such materials hold great promise for use in diverse applications in smart sensors and actuators, force probes in biomedical engineering, structural elements for absorption of microwaves and elastic waves, etc. in this paper, a Timoshenko beam model for chiral materials is developed based on noncentrosymmetric micropolar elasticity theory. The governing equations and boundary conditions for a chiral beam problem are derived using the variational method and Hamilton＇s principle. The static bending and free vibration problem of a chiral beam are investigated using the proposed model. it is found that chirality can significantly affect the mechanical behavior of beams, making materials more flexible compared with nonchiral counterparts, inducing coupled twisting deformation, relatively larger deflection, and lower natural frequency. This study is helpful not only for understanding the mechanical behavior of chiral materials such as DNA and chromatin fibers and characterizing their mechanical properties, but also for the design of hierarchically structured chiral materials.

关键词： Timoshenko beam model Chiral material Chirality Deflection Microrotation

TEMPERATURE DEPENDENCE OF PERMEABiLiTy OF Co_(66)Fe_4Mo_2si_(16)B_(12) ALLOy

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Acta Metallurgica sinica(English Letters) 2007年第4期20卷 284-286页

作者： y.j. Zhang X.H. Li s. Wang K.y. He College of Material and Metallurgy Northeastern University Shenyang 110004 China College of Aerospace Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

At different annealing temperatures, the saturation magnetostrictions and the correlation between the permeability μi and the temperature T （μi-T curves） of the Co66Fe4Mo2si16B12 alloy were investigated using a small-angle magnetization tester and core tester. The experimental results showed that the μi-T curves had different shapes at different ranges of annealing temperature; the permeability μi of the alloy improved with the increase of the annealing temperatures below 460℃; when the alloy was annealed above 480℃, the poor magnetic properties were considered to be caused by larger saturation magnetostriction.

关键词： Co66Fe4Mo2si16B12 alloy amorphous nanocrystalline alloy permeability saturation magnetostriction

sTRUCTURE iMPROVEMENT AND TEMPERATURE FiELD siMULATiON OF PREPARiNG NANOPOWDER By EVAPORATiON-CONDENsATiON METHOD

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Acta Metallurgica sinica(English Letters) 2008年第3期21卷 178-182页

作者： j.s. Bao y. yin T.G. Liu Z.y. yang school of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou221116 China

A new apparatus, with a segregable conical water cooling condenser, which is heated by an electric arc using the evaporation-condensation method to prepare carbon-coated nanopowder, has been developed by the authors. Numerical simulation of the temperature field is done by the ANsys software, and temperature in the reaction vessel is measured with the help of an experiment, to verify the simulation result. influence of the temperature field in the reaction vessel, on the process of preparing nanopowder is then discussed simply. it is shown that the segregable conical water cooling condenser and carbon-coated surface process can be used to prepare steady carbon-coated metal nanopowder, at a lower cost and higher yield rate than the traditional structure. simulation of the temperature field in the apparatus shows that the arc heating method can form a temperature field in the apparatus, which is quite favorable for nanopowder formation. Experiments show that the rational parameters using this apparatus, with the arc heating method to prepare carbon-coated nanopowder are electricity 60-100 A and arc length 5-8 mm.

关键词： Evaporation-condensation method Electric arc heating Temperature field Condenser structure

Doppler Global Velocimeter-Development and Validation with Measurements in a Round Free jet

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journal of Thermal science 2009年第1期18卷 74-84页

作者： X.Ottavy s.Goguey j.Berthiau i.Trébinjac Laboratoire de Mécanique des Fluides et d’Acoustique(LMFA)

Doppler global velocimetry （DGV） has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave （CW） argon ion laser for ermssion, lne receiver ieatures only one camera for both signal and reference images and incorporates a DEF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.

关键词： laser anemometry Doppler shift iodine vapor absorption line filter DEFi system image processing.

superplasticity of Ti2448 Alloy with Nanostructured Grains

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journal of Materials science & Technology 2011年第12期27卷 1099-1104页

作者： M.j. Xiao y.X. Tian G. W. Mao s.j. Li y.L. Hao R. yang school of Astronautics Northwestern Polytecllnic University Xi＇an 710072 China - shenyang National Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Ti-24Nb-4Zr-8sn, abbreviated as Ti2448 from its chemical composition in weight percent, is a multifunctional /3 type titanium alloy with body centered cubic （bcc） crystal structure, and its highly localized plastic deformation behavior contributes significantly to grain refinement during conventional cold processing. in the paper, the nanostructured （Ns） alloy with grain size less than 50 nm produced by cold rolling has been used to investigate its superplastic deformation behavior by uniaxial tensile tests at initial strain rates of 1.5 ×10-2, 1.5×10^-3 and 1.6×10-4 s-1 and temperatures of 600,650 and 700℃. The results show that, in comparison with the coarse-grained alloy with size of 50 μm, the Ns alloy has better superplasticity with elongation up to ～275% and ultimate strength of 50-100 MPa. strain rate sensitivity （m） of the Ns alloy is 0.21, 0.30 and 0.29 for 600,650 and 700℃, respectively. These results demonstrate that grain refinement is a valid way to enhance the superplasticity of Ti2448 alloy.

关键词： Titanium alloy bcc crystal superplasticity Nanostructured grain

inhomogeneous dealloying kinetics along grain boundaries during liquid metal dealloying

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journal of Materials science & Technology 2022年第11期106卷 41-48页

作者： s.-H.joo y.B.jeong T.Wada i.V.Okulov H.Kato Department of Materials science and Engineering Dankook University119 Dandae-roCheonan 31116Korea institute for Materials Research Tohoku UniversityKatahira 2-1-1Sendai 980-8577Japan institute of Natural sciences and Mathematics Ural Federal University620000 EkaterinburgRussia Faculty of Production Engineering University of BremenBadgasteiner Str.128359 BremenGermany Leibniz institute for Materials Engineering-iWT Badgasteiner Str.328359 BremenGermany

in this study, the inhomogeneous dealloying phenomenon during the liquid metal dealloying(LMD) was investigated using FeNi+Mg and(FeCo)Ni+Mg systems. For the FeNi+Mg system, the inhomogeneous dealloying and wetting of Mg melt occurred along triple junction(Tj) and grain boundary(GB).Temperature increase enhances the inhomogeneous dealloying kinetics and leads to the formation of the plate-shaped abnormal ligaments at the GB region. The energy banlance between a GB energy(γGB)and solid-liquid interface energies(γsl) is the key factor governing the inhomogeneous dealloying and wetting. Particularly, the low-energy twin boundaries were unaffected by the inhomogeneous ***, precursor microstructure is an important factor determining the final morphology of dealloyed material as well as its physical properties. in the case of the(FeCo)Niprecursor, all Tj and GB were stable against the preferred penetration of Mg melt from 600 ℃ to 800 ℃. it was concluded that a minor addition of alloying elements(VorCr) changes GB characteristics as well as γslof the precursor ***, this significantly influences dealloying mechanisms and final morphology of the dealloyed material. The current findings demonstrate the importance of GB engineering in the precursor materials for the technological application of liquid metal dealloying for the synthesis of advanced structural and functional materials.

关键词： Liquid metal dealloying inhomogeneous dealloying Dealloying mechanism Abnormal ligament Porous material