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KINETIC STuDY OF SPINEl liMn_2O_4 SYNTHESIzED BY SOlID REACTION WITH SOFT-CHEMICAl METHOD

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Acta Metallurgica Sinica(English letters) 2005年第4期18卷 512-518页

作者： C.q. Xu Y. W. Tian Y. C. zhai z.J. Guo z. q. Huang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

The differential thermal analysis （DTA） curves were measured at different heating rates in flowing air for studying the synthesis of the spinel liMn2O3 with li2CO3 and MnO2, The reaction began at about 503K, and finished at about 873K. The apparent activation energy of Kissinger method was about ***^-1, the reaction orderwas 1.67, the frequency factor was 7.81×10^9, and therefore the dinetic epuation was dδ/dt=A·exp（- E/RT）·（1-δ）^n=7.81×10^9, exp（-122770/RT）·（l-δ）^1.67 . Coats-Redfem integral method was used to analyze the DTA curves of the samples at different heating rates, and the calculated apparent activation energy and frequency factor were 112. 13kJ· mol^-1 and 1.18 × 10^9, respectively, rather close to that of Kissinger method. X-ray diffraction （XRD） and scanning electron microscope （SEM） results shown that the synthesized liMn2O3 possesses pure phase, regular shape and normal particle distribution.

关键词： lithium manganese oxides synthesized kinetics Kissinger method,Coats-Redfern integral method

^(199)Sn AND ^(57)Fe MOSSBAuER SPECTROSCOPIC STuDY OF THE MECHANICAllY AllOYED Fe-Sn AllOYS

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Acta Metallurgica Sinica(English letters) 1998年第5期11卷 335-341页

作者： Y.z.Yang Y.l.zhu q.S.li X.M.Ma Y.D.Dong Y.z.Chuang Guangdong univ of Technology Guangzhou China

Nanocrystalline supersaturated solid solutions (Sa in Fe) with Sn content less than 50 at. %,and FeSn2 and Fe1.3Sn intermetallic compounds have been prepared by mechanical alloying of Fe and Sn mixture powders with composition of Fe1-xSnx (x≤0.5).The atomic alloying the formation and microstructure, especially the coordination environments, of the resultant alloys have been studied by X-ray diffraction, 57Fe and 119Sn Mossbauer Spectroscopy and diffrrential scanning calorimetry. The Fe and Sn coordination environments and the composition dependence of the hyperfine parameters on the Fe and Sn content have been fully discussed with respect to the solid dissolution alloying, grain refinement, and distortion caused or induced by mechanical alloying.

关键词： mechanical alloying Mossbauer effect nanocrystalline Fe-Sn alloy

Further investigation on the fusion of ^(6)li with ^(209)Bi target at near-barrier energies

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Chinese Physics C 2024年第7期48卷 106-117页

作者：张高龙焦振威张广鑫 M.R.Cortes 胡世鹏钱建强 D.Mengoni 屈卫卫李聪博郑云张焕乔孙慧斌王楠张春雷 J.J.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.la Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.Illana S.Bakes I.zanon S.Aydin G.de Angelis M.Siciliano R.Menegazzo S.M.lenzi J.l.Ferreira J.Rangel Serkan Akkoyun l.F.Canto J.lubian School of Physics Beihang UniversityBeijing 100191China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340NiteróiRio de JaneiroBrazil Institute for Advanced Study in Nuclear Energy&Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPadovaItaly Dipartimento di fisica Astronomia dell'universita di padova PadovaItaly State Key laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China INFN Laboratori Nazionali di LegnaroI-35020 LegnaroItaly INFN Sezione di NapoliI-80126 NapoliItaly Dipartimento di Farmacia Universitàdi Napoli"Federico II"I-80131 NapoliItaly Department of Natural and Mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkiye Physics Division Argonne National LaboratoryLemont-ILUSA Departamento de Matemaética Física e Computaç˜ao Universidade do Estado do Rio de JaneiroFaculdade de Tecnologia27537-000ResendeRio de JaneiroBrazil Department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroCP 6852821941-972Rio de JaneiroBrazil

The complete and incomplete fusion cross sections for ^(6)li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb *** cross sections of(deuteron captured)incomplete fusion(ICF)products were re-quantified experimentally for this reaction *** results reveal that the ICF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CDCC)method was performed for the aforementioned CF and ICF cross sections;the result is consistent with the *** universal fusion function(uFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

关键词： cross section incomplete fusion suppression factor weakly bound nuclei

Ground-based and additional science support for SMIlE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter M.Dunlop C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh z.-J.Hu M.K.James l.Juusola K.Kauristie E.A.Kronberg M.lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae l.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.zhang q.-H.zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca university AthabascaCanada ESTEC European Space AgencyNetherlands university of Saskatchewan SaskatoonCanada The Johns Hopkins university Applied Physics laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji university Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China Finnish Meteorological Institute(FMI) Finland Department of Earth and Environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GFz German Research Centre for Geosciences PotsdamGermany Nagoya university Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria university Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere link Explorer(SMIlE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMIlE ***,we describe current community efforts to prepare for SMIlE,and the benefits and context various experiments that have explicitly expressed support for SMIlE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SMIlE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMIlE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMIlE conjunctions missions

EFFECT OF STRuCTuRAl PARAMETERS ON THE THERMAl STRESS OF A NiFe_(2)O_(4)-BASED CERMET INERT ANODE IN AluMINuM ElECTROlYSIS

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Acta Metallurgica Sinica(English letters) 2007年第2期20卷 139-147页

作者： J. li z.G. Wang Y.q. lai Y.Y. Wu S.l. Ye School of Metallurgy Science and Engineering Central South University Changsha 410083 China

Inert anode has been a hot issue in the aluminum industry for many decades. With the help of FEA （finite element analysis） software ANSYS, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, and the radius of inner chamfer and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the major cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.

关键词： inert anode thermal stress structural parameter aluminum electrolysis

PHOSPHORuS GRAIN BOuNDARY SEGREGATION IN A P-DOPED 2.25Cr1Mo STEEl

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Acta Metallurgica Sinica(English letters) 2004年第5期17卷 639-644页

作者： D.D.Shen z.X.Yuan J.liu S.H.Song l.q.Wen TheHubeiProvinceKeylaboratoryofCeramicsandRefractories WuhanUniversityofScienceandTechnologyWuhan430081China SchoolofMaterialsScienceandEngineering NanjingUniversityofAeronauticsandAstronauticsNanjing210016China

Grain boundary segregation of phosphorus during tempering at 540℃ after quenching from 980℃ is examined for a P-doped 2.25Cr1Mo steel by means of Auger electron spectroscopy. The solute-boundary binding energy and the diffusion coefficient for phosphorus are determined by virtue of the measured segregation kinetics along with the equilibrium segregation theory. The obtained values of the above parameters are discussed with comparison to those found in the literature for low-alloy steels.

关键词： segregation grain boundary low-alloy steel phosphorus

NuMERICAl SIMulATION OF INDuCTION SKull MElTING PROCESS FOR TITANIuM-AluMINIuM BASE AllOY

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Acta Metallurgica Sinica(English letters) 2004年第6期17卷 928-933页

作者： z.Y.Chen l.J.Xu F.T.Kong q.Shu Y.Y.Chen SchoolofMaterialsScienceandEngineering HarbinInstituteofTechnologyHarbin150001China

The mathematics model for temperature field of water-cooling copper crucible induction skull melting process was established. The program for simulating temperature field of melting process was developed with finite element method. The temperature field of the melting process for Ti-47Al-2Cr-2Nb alloy was calculated. During melting period, the temperature is raised gradually along radius augmentation direction. The elements of the charge near the crucible wall are molten first. The center elements of the charge are molten last. The melting time of the center element is just that of all the charge melting. The melting time of Ti-47Al-2Cr-2Nb alloy is 15min. In which, the charge was heated by low power 80kW for 9min and by high power 300kW for 6min. When melting Ti-47Al-2Cr-2Nb alloy, the loading power is nearly direct proportion to melt temperature. Increasing loading power may raise melt temperature. The best melting power of Ti-47Al-2Cr-2Nb alloy is 305-310kW. This is identical with the melting test and has guidance sense to the melting process of actual titanium alloy.

关键词： TiAl base alloy melting numerical simulation

Performance of Sacrificial Anodes in Reinforced Concrete

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武汉理工大学学报 2010年第17期32卷 165-169页

作者： Tu l q DONG C WANG C J zHANG G z lEI Y F SHuI z H School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Wuhan Harbour Engineering Design & Research Co. ltd Wuhan 430071China Key lab of large-span Bridge Construction Technology Minstry of CommunicationsWuhan 430071China zhejiang Province zhoushan Island linking Construction Commanding Department Zhoushan 316032China

The electrochemical performance of the anodes was measured in the reinforced concrete test block in artificial sea water. Their chemical composition,metallographic structure and surface morphology were analyzed. It was found that concrete mix proportion and the covering layer thickness had an impact on the performance of sacrificial anodes. The thermal-sprayed zinc alloy anodes had a more negative corrosion potential and larger galvanic current than metallurgy ones in the same conditions. They had similar chemical composition. But metallographic structure showed that the structure of thermal-sprayed zinc alloy anodes was a loose porous. This structure had the catalytic effect on the andes electrochemical reactions and made the anodes the electrochemical exchange current density increase and the corrosion potential move to negative direction.

关键词： sacrificial anode reinforced concrete concrete mix proportion thermal-sprayed anodes electrochemical performance

STuDY THE INFluENCE OF H_(3)BO_(3)ON THE zINC ElECTROPlATING uSING ElECTROCHEMICAl NOISE TECHNIquE

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Acta Metallurgica Sinica(English letters) 2004年第5期17卷 661-666页

作者： z.zhang C.S.Wu q.Y.Cai Y.l.Cheng F.H.Cao J.q.zhang C.N.Cao DepartmentofChemistry ZhejiangUniversityHangzhou310027China StateKeylaboratoryforCorrosionandProtection InstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China

The influence of H3BO3 on the zinc electroplating was studied using electrochemical noise technique, cyclic voltammetry and steady-state polarization method. The results showed that, under the experimental conditions, the deposition of zinc followed the mechanism of two-dimensional nucleation and subsequent grain growth. The addition of H3BO3 into the electroplating solution prominently changes the nucleation and growth kinetics of zinc deposits, which is directly related to the features of electrocrystallization noise and the corresponding structure of the electrodeposits. The results also shown that the electrochemical noise (EN) technique can give more information about the electrodeposits structure and electroplating mechanism than other normal electrochemical measurements can give, such as steady-state polarization method and cyclic voltammetry technique.

关键词： zinc electroplating electrochemical noise electrocrystallization