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SEPARATION OF THORIUM FROM yTTERBIUM WITH CyANEX272 By USING A HOllOW FIBER MEMBRANE EXTRACTOR

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Acta Metallurgica Sinica(English letters) 2001年第2期14卷 132-136页

作者： F.J. Zhang, F. luo, D.Q. li and y.l. Wu (laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, The Chinese Academy of Sciences, Changchun 130022, China) (State Key Joint of Environment Simulation and Pollution Control, laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry The Chinese Academy of Sciences

The based membrane extraction of Th(IV) and yb(III) was studied with HBTMPP in heptane. The separation process of Th(IV) and yb(III) was considered to be a kinetics competition one. The separation for the mixture of Th(IV) and yb(III) was carried out by successive membrane extraction and stripping simultaneously. The concentration ratio of Th(IV) and yb(III) is 16.74 in the stripping solution. The recovery of Th(IV) is 71.6%. The purity of Th(IV) is 95.74%. The separation factor of Th(IV) and yb(III) is 2.52×106, which was obtained by interfacial kinetics.

关键词： Extraction Fibrous membranes Kinetic theory Separation ytterbium

SyNTHESIS AND SOliD STATE SINTERING OF W-Ni-Fe NANO-COMPOSITE POWDERS

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Acta Metallurgica Sinica(English letters) 2000年第3期13卷 917-920页

作者： Qu, X.H. Fan, J.l. li, y.M. Huang, B.y. Central South Univ of Technology Changsha China

The mixture of 90 wt%W, 7 wt%Ni and 3 wt%Fe elemental powders was milled in a planetary high-energy ball mill. The evolution of the structure during milling and the sintering behavior of the milled powders were tested. The results showed that by mechanical alloying W(Ni, Fe) supersaturated solid solution with nano-meter size formed, which can enhance the sintering process. Fully dense alloy from the milled powders was obtained through solid state sintering. The tensile strength of the obtained alloy is over 900 MPa which is comparable to that of the alloy sintered by traditional liquid-phase sintering from un-milled powders of the same composition.

关键词： Tungsten alloys Nickel alloys Iron alloys Mechanical alloying Powder metals Sintering Morphology Tensile strength

Surface Characterization and Cell Response of Binary Ti-Ag Alloys with CP Ti as Material Control

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Journal of Materials Science & Technology 2012年第9期28卷 779-784页

作者： B.B. Zhang K.J. Qiu B.l. Wang l. li y.F. Zheng Center for Biomedical Materials and Engineering Harbin Engineering University Harbin 150001 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

In this study, the surface passive films, dissolution behavior and biocompatibility of Ti-Ag alloys （with 5%, 10% and 20% Ag） were evaluated by X-ray diffraction （XRD） tests, electrochemical corrosion tests, X-ray photoelectron spectroscopy （XPS） tests, dissolution tests and in-vitro cytotoxicity tests. The surface films on the Ti-20Ag alloy are rich in Ti and much deficient in Ag with respect to alloy composition, as identified by XPS. Compared to CP Ti, Ti-SAg and Ti-20Ag alloys show larger impedances and lower capacitances, which can be associated with an increase of the passive layer thickness. Moreover, all Ti-Ag alloys exhibit negligible or low metal release in the test solutions. The in-vitro cytotoxicity results show Ti-Ag alloys seem to be as cytocompatible as CP Ti. From the viewpoint of surface passive film and cytotoxicity, Ti-SAg and Ti-20Ag are considered to be more suitable for dental applications.

关键词： Ti-Ag alloy Surfaces Electrochemical corrosion Cytotoxicity

REVIEW AND PROSPECT OF HIGH STRENGTH lOW AllOy TRIP STEEl

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Acta Metallurgica Sinica(English letters) 2003年第6期16卷 457-465页

作者： l.li P.Wollants y.l.He B.C.DeCooman X.C.Wei Z.y.Xu SchoolofMat.Sci.＆Eng. ShanghaiUniversityShanghai200072China Dept.MTM KatholiekeUniversiteitLeuvenB-3001LeuvenBelgium Dept.MetallurgyandMaterialsScience UniversiteitGentBelgium Dept.Mat.Sci＆Eng. ShanghaiJiaotongUniversityShanghai200030China

Research status of high strength low alloy TRIP (transformation induced plasticity) steels for automobile structural parts is briefly described. Composition and microstruc-ture factors especially the morphology, size and volume fraction of retained austenite, which largely influence the strength and ductility of the steel, are reviewed and discussed one after another. Modelling of the inter-critical annealing and martempering processes as well as the designing of the TRIP steel aided by commercial software are introduced. Some special aspects of the dynamic mechanical properties of TRIP steel are firstly reported.

关键词： HSlA TRIP steel retained austenite dynamic mechanical prop-erty thermodynamics kinetics

Improved mechanical properties in titanium matrix composites reinforced with quasi-continuously networked graphene nanosheets and in-situ formed carbides

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Journal of Materials Science & Technology 2022年第1期96卷 85-93页

作者： Q.yan B.Chen l.Cao K.y.l.u S.li l.Jia K.Kondoh J.S.li State Key.l.boratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Joining and Welding Research Institution Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan

In order to construct quasi-continuously networked reinforcement in titanium(Ti)matrix composites,in this study,Ti-6 Al-4 V spherical powders were uniformly coated with a graphene nanosheet(GNS)layer by high energy ball milling and then consolidated by spark plasma *** showed that the GNS layer on the powder surface inhibited continuous metallurgy bonding between powders during sintering,which led to the formation of quasi-networked hybrid reinforcement structure consisting of insitu Ti C and remained *** networked GNSs/Ti64 composite possessed noticeably higher tensile strength but similar ductility to the Ti64 alloy.l.ading to both better tensile strength and ductility than the GNSs/Ti composite with randomly dispersed GNSs and Ti *** formation mechanism and the fracture mechanism of the networked hybrid reinforcement were *** results provided a method to fabricate Ti matrix composites with high strength and good ductility.

关键词： Titanium matrix composites(TMCs) Graphene Network structure Strength Ductility

Influence of Co Content on Raman and Photoluminescence Spectra of Co Doped ZnO Nanowires

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Journal of Materials Science & Technology 2012年第4期28卷 313-316页

作者： y.Q. Chang P.W. Wang S.l. Ni y. long X.D. li School of Materials Science anti Engineering University of Science and Technology Beijing Beijing 100083 China Department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Co doped ZnO nanowires with different Co contents have been fabricated by a chemical vapor deposition method. X-ray diffraction results show that all the samples are of single phase and crystallize in wurtzite ZnO structure. The lattice parameter a increases with increasing Co content, while the parameter c has no obvious change with increasing Co. Raman spectra show that the nonpolar E2（High） mode becomes broad and weak with the doping of Co, which indicates that the incorporation of Co causes structural disorder in the crystalline columnar ZnO lattice. The photolurninescence spectra exhibit that the position of the ultraviolet emission shifts to short wavelength and the intensity decreases with increasing Co. The green emission is affected by two contrary factors. It is increased by the introduced defects, but suppressed by the interaction between Co doping and native defects and the later affects it more significantly.

关键词： Co doped ZnO nanowires Raman Photoluminescence Single phase

A low-cost and High Efficiency Architecture of AES Crypto-engine

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China Communications 2008年第2期5卷 8-15页

作者： Z.F.Zhao D.y.yu l.li Vinno Technologies Inc

The growing market of WPAN has led to an increasingdemand of security measures and devices forprotecting the user data transmitted over the *** Encryption Standards(AES)isthe basic security approach for *** meet thelow cost,low power feature and high security demandof WPAN,a low cost,high efficient AES coreis proposed in this *** achieve low cost,methods of integration and resource sharing are usedin designing a very.l.w-complexity architecture,especially in(inverse)byte substitution(inv)SubBytes)modules and(inverse)mix column(inv)MixColumn)modules,*** more,AESEncryptor and Decryptor is integrated into a fullfunctional *** very.l.w-cost andhigh efficiency AES core of IEEE 802.15.4-2006 isdesigned and emulated on Xilinx *** show that this kind of design can be used inresource critical applications,such as smart card,PDA and mobile phones.

关键词： AES S-box Sub-Byte WPAN

Molecular Dynamics Simulation of Porous layer-enhanced Dislocation Emission and Crack Propagation in Iron Crystal

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Journal of Materials Science & Technology 2011年第11期27卷 1025-1028页

作者： D. li F.y. Meng X.Q. Ma l.J. Qiao W.y. Chu Department of Physics University of Science and Technology Beijing Beijing 100083 China Corrosion and Protection Center Key Lab of Environmental Fracture （Ministry of Education） University of Science and Technology Beijing Beijing 100083 China

The internal stress induced by a porous layer or passive layer can assist the applied stress to promote dislocation emission and crack propagation, e.9. when the pipeline steel is buried in the soil containing water, resulting in stress corrosion cracking （SCC）. Molecular dynamics （MD） simulation is performed to study the process of dislocation emission and crack propagation in a slab of Fe crystal with and without a porous layer on the surface of the crack. The results show that when there is a porous layer on the surface of the crack, the tensile stress induced by the porous layer can superimpose on the external applied stress and then assist the applied stress to initiate crack tip dislocation emission under lowered stress intensity KI, or stress. To respond to the corrosion accelerated dislocation emission and motion, the crack begins to propagate under lowered stress intensity KI, resulting in SCC.

关键词： Molecular dynamics simulation Dislocation emission Crack propagation Porouslayer Stress intensity

Molecular dynamics simulation and continuum modelling of granular surface flow in rotating drums

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Chinese Science Bulletin 2007年第5期52卷 692-700页

作者： li ShuiQing yAO Qiang CHEN Bing ZHANG Xuan DING y l Department of Thermal Engineering Tsinghua University Beijing 100084 China Department of Chemical Engineering University of Leeds Leeds LS29JT UK

Numerical simulations of granular flows in rotating drums operated at medium to high rates (Fr=0.1― 0.2) have been carried out by using a Molecular Dynamics (MD) algorithm that incorporates inelastic particle interactions, sliding friction and rolling friction. The results indicate that the behavior of granular flow in rotating drums can be classified into two distinct zones: a shear active layer at the bed surface and a quasi-static plug flow region adjacent to the wall. The residence time of a tracer particle in the active layer is approximately a third or a half of that in the plug flow region. The thickness of the active layer at mid-chord is about 0.57―0.61 times that of the plug flow region. It is found that all cases simulated in this work are in the rolling-cascading intermediate regime instead of the pure rolling re-gime. The simulated tangential velocity at the mid-chord is also compared with experimental results reported in the literature and good agreement has been obtained. Based on the MD simulations and experimental results, a continuum approach has also been developed. It is shown that the behavior of granular solids in the plug flow region experiences plastic deformation along the radial direction from the wall with the velocity profiles well described by an exponential function, whereas the active layer velocity follows a simple expression for the Couette shear flow. Discussion has also been made on the granular temperature and concentration profiles.

关键词：粒料颗粒表面流分子动力学模拟连续模型转鼓