检索结果-南通市图书馆

TENSILE STRESS RELAXATION Of TURBINE BOLT STEELS AT hIGh TEMPERATURE

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 542-547页

作者： G.Q.Jia h.W.shen Y.M.Zhu Metallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 ChinaMetallurgical Department. Shanghai Turbine Company Ltd. Shanghai 200240 China

Stress relaxation behavior of two turbine bolt steels was evaluated by the manual-controlled tensile stress relaxation test (TSRT) at high temperature. first, feasibility and the procedure of the manual-controlled tensile stress relaxation test (TSRT) is discussed and carried out on a general creep testing machine. And then, the experimental results from such type of test were compared to the existing data provided by certain Laboratory U.K. Overall good agreement between the results of manual-controlled TSRT method and the existing data provides confidence in the use of the proposed method in practice. finally, the experimental results of turbine bolt steels from TSRT were compared with that of bending test. It is observed that great difference exists between the results from two different type stress relaxation tests. It is therefore suggested that the results from TSRT method be adopted in turbine bolt design in engineering.

关键词： tensile stress-relaxation test bending stress-relaxation test turbine bolt steels

Scale dependence of direct shear tests

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2009年第23期54卷 4337-4348页

作者： ZhOU Qiang shen hayley h hELENBROOK Brian T ZhANG hongWu Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China Department of Civil and Environmental Engineering Clarkson University Potsdam NY 13699-5710 USA Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

Direct shear test has been widely used to measure the shear strength of soils and other particulate materials in industry because of its simplicity. however, the results can be dependent on the specimen size. The ASTM (American Society for Testing and Materials) publications suggest that for testing soils the shear box should be at least ten times the diameter of the largest particle and the height of the box should be no more than half of its diameter. These guidelines are empirically based. A series of two-dimensional numerical direct shear tests are performed to investigate this scaling effect. By analyzing the bulk friction, particle translation and rotation, percentage of sliding, average volume (area) and shear strain and the evolution of the shear band, we find that the traditional guidelines for direct shear tests are questionable. Scaling dependency of bulk friction on the property of granular materials is clearly present. Our current analysis points out that the scaling effects can vary significantly depending on the particle properties other than their sizes. Of all the parameters we observed, particle rotation appears to have a decisive correlation with the bulk friction. formation of a shear band is universal. As the shearing progresses, particle rotation begins to concentrate near the shear plane. By defining the width of a shear band as the standard deviation of the distribution of translational gradient or the standard deviation of the distribution of particle rotation, quantitative evolutions of shear band are presented. Both measures of the shear band width dropped rapidly during pre-failure stage. After peak stress both measures begin to approach steady state as the bulk friction stabilizes to the residual stage. These observations suggest that structure formation inside the shear band controls the scaling effect.

关键词：直接剪切试验测试土力学土工试验

Grain refinement mechanism of Mg-3Sn-1Mn-1La alloy during accumulative hot rolling

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第32期91卷 251-261页

作者： Z.Y.Zhao R.G.Guan Y.f.shen P.K.Bai School of Materials Science and Engineering North University of ChinaTaiyuan 030051China bEngineering Research Center of Continuous Extrusion Ministry of EducationDalian Jiaotong UniversityDalian 116028China Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang 110004China

We elucidate the effect of lanthanum(La) on the grain refinement of Mg-3 Sn-1 Mn alloy during accumulative hot rolling. The lath-shaped Mg_(2) Sn phase in the Mg-3 Sn-1 Mn alloy is firstly broken and spheroidized,and then the size increases and coarsens with the increase of rolling reduction, most of Mg_(2) Sn move from grain boundary to grain and are homogeneously distributed within the matrix. however, the plate-shaped Mg Sn La compound in Mg-3 Sn-1 Mn-1 La gradually becomes fine, spheroidized, and homogeneously distributed. The grain sizes of Mg-3 Sn-1 Mn and Mg-3 Sn-1 Mn-1 La alloys become fine through dynamic recrystallization(DRX), though the grain refinement of Mg-3 Sn-1 Mn-1 La alloy is better compared to the Mg-3 Sn-1 Mn alloy. A large number of uniformly distributed spherical Mg Sn La compounds pin the dislocations, thus increasing the dislocation density. hence, the driving force for DRX increases and promotes the formation of deformation bands and more twins, providing the sites for DRX nucleation and growth.

关键词： Mg alloy Grain refinement Dynamic recrystallization Accumulative hot rolling

The Effect of the Chain Length on MMA free Radicl Polymerization

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2001年第11期12卷 1041-1042页

作者： Wang, M Mao, YG Lu, YY Yang, Rf Li, f shen, JC Jilin Univ Minist Educ Key Lab Supramol Struct & Spect Changchun 130023 Peoples R China

In the polymerization process of methyl methacrylate (MMA), the Arrhenius parameters (activation energy and frequency factor) of propagating reaction monotonically decrease with increasing monomer conversion. At the beginning and middle stage of the propagating reaction, the increase of radical chain length is the main reason of above mentioned change. And at the end stage, the sharp decrease of k(p) indicates that the activation energy is approximately incline to zero and the propagating reaction is controlled by molecular diffusion motion.

关键词： MMA Arrhenius parameters propagating reaction radical chain length

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第12期48卷 1-10页

作者： M.Ablikim M.N.Achasov P.Adlarson O.Afedulidis X.C.Ai R.Aliberti A.Amoroso Q.An Y.Bai O.Bakina I.Balossino Y.Ban h.-R.Bao V.Batozskaya K.Begzsuren N.Berger M.Berlowski M.Bertani D.Bettoni f.Bianchi E.Bianco A.Bortone I.Boyko R.A.Briere A.Brueggemann h.Cai X.Cai A.Calcaterra G.f.Cao N.Cao S.A.Cetin J.f.Chang G.R.Che G.Chelkov C.Chen C.h.Chen Chao Chen G.Chen h.S.Chen h.Y.Chen M.L.Chen S.J.Chen S.L.Chen S.M.Chen T.Chen X.R.Chen X.T.Chen Y.B.Chen Y.Q.Chen Z.J.Chen Z.Y.Chen S.K.Choi G.Cibinetto f.Cossio J.J.Cui h.L.Dai J.P.Dai A.Dbeyssi R.E.de Boer D.Dedovich C.Q.Deng Z.Y.Deng A.Denig I.Denysenko M.Destefanis f.De Mori B.Ding X.X.Ding Y.Ding Y.Ding J.Dong L.Y.Dong M.Y.Dong X.Dong M.C.Du S.X.Du Y.Y.Duan Z.h.Duan P.Egorov Y.h.fan J.fang J.fang S.S.fang W.X.fang Y.fang Y.Q.fang R.farinelli L.fava f.feldbauer G.felici C.Q.feng J.h.feng Y.T.feng M.fritsch C.D.fu J.L.fu Y.W.fu h.Gao X.B.Gao Y.N.Gao Yang Gao S.Garbolino I.Garzia L.Ge P.T.Ge Z.W.Ge C.Geng E.M.Gersabeck A.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl S.Gramigna M.Greco M.h.Gu Y.T.Gu C.Y.Guan A.Q.Guo L.B.Guo M.J.Guo R.P.Guo Y.P.Guo A.Guskov J.Gutierrez K.L.han T.T.han f.hanisch X.Q.hao f.A.harris K.K.he K.L.he f.h.heinsius C.h.heinz Y.K.heng C.herold T.holtmann P.C.hong G.Y.hou X.T.hou Y.R.hou Z.L.hou B.Y.hu h.M.hu J.f.hu S.L.hu T.hu Y.hu G.S.huang K.X.huang L.Q.huang X.T.huang Y.P.huang Y.S.huang T.hussain f.hölzken N.hüsken N.in der Wiesche J.Jackson S.Janchiv J.h.Jeong Q.Ji Q.P.Ji W.Ji X.B.Ji X.L.Ji Y.Y.Ji X.Q.Jia Z.K.Jia D.Jiang h.B.Jiang P.C.Jiang S.S.Jiang T.J.Jiang X.S.Jiang Y.Jiang J.B.Jiao J.K.Jiao Z.Jiao S.Jin Y.Jin M.Q.Jing X.M.Jing T.Johansson S.Kabana N.Kalantar-Nayestanaki X.L.Kang X.S.Kang M.Kavatsyuk B.C.Ke V.Khachatryan A.Khoukaz R.Kiuchi O.B.Kolcu B.Kopf M.Kuessner X.Kui N.Kumar A.Kupsc W.Kühn J.J.Lane L.Lavezzi T.T.Lei Z.h.Lei M.Lellmann T.Lenz C.Li C.Li C.h.Li Cheng Li D.M.Li f.Li G.Li h.B.Li h.J.Li h.N.Li hui Li J.R.Li J.S.Li K.Li L.J.Li L.K.Li Lei Li M.h.Li P.R.Li Q.M.Li Q.X.Li R.Li S.X.Li T.Li W.D.Li W.G.Li X.Li X.h.Li X.L.Li X.Y.Li X.Z.Li Y.G Institute of high Energy Physics Beijing 18049China Beihang University Beijing 18191China Bochum Ruhr-University D-44780 BochumGermany Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia Carnegie Mellon University PittsburghPennsylvania 15213USA Central China Normal University Wuhan 430079China Central South University Changsha 41883China China Center of Advanced Science and Technology Beijing 18190China China University of Geosciences Wuhan 430074China Chung-Ang University Seoul06974Republic of Korea COMSATS University Islamabad Lahore CampusDefence RoadOff Raiwind Road54000 LahorePakistan fudan University Shanghai 200433China GSI helmholtzcentre for heavy Ion Research Gmbh D-64291 DarmstadtGermany Guangxi Normal University Guilin 54184China Guangxi University Nanning 530004China hangzhou Normal University Hangzhou 31836China hebei University Baoding 07182China helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany henan Normal University Xinxiang 453007China henan University Kaifeng 475004China henan University of Science and Technology Luoyang 47183China henan University of Technology Zhengzhou 450001China huangshan College Huangshan 245000China hunan Normal University Changsha 41881China hunan University Changsha 41882China Indian Institute of Technology Madras Chennai 600036India Indiana University BloomingtonIndiana 47405USA INfN Laboratori Nazionali di frascati INFN Laboratori Nazionali di FrascatiI-00044FrascatiItaly INfN Laboratori Nazionali di frascati INFN Sezione di PerugiaI-0618PerugiaItaly INfN Laboratori Nazionali di frascati University of PerugiaI-0618PerugiaItaly INfN Sezione di ferrara INFN Sezione di FerraraI-44122FerraraItaly INfN Sezione di ferrara University of FerraraI-44122FerraraItaly Inner Mongolia University Hohhot 01821China Institute of Modern Physics Lanzhou 730000China Institute of Physics and Technology Peace Avenue 54BUlaanbaatar 13330Mongolia Instituto de Alta Investigación Universidad de Tarapacá

We present a measurement of the integrated luminosity of e^(+)e^(-)collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm=3.773 *** integrated luminosities of the datasets taken from December 2021 to June 2022,from November 2022 to June 2023,and from October 2023 to february 2024 were determined to be 4.995±0.019 fb^(-1),8.157±0.031 fb^(-1),and 4.191±0.016 fb^(-1),respectively,by analyzing large angle Bhabha scattering *** uncertainties are dominated by systematic effects,and the statistical uncertainties are *** results provide essential input for future analyses and precision measurements.

关键词： Bhabha scattering events integrated luminosity cross-section

A Note on the Invariance Properties and Conservation Laws of the Kadomstev–Petviashvili Equation with Power Law Nonlinearity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第9期28卷 10-11页

作者： A h Bokhari f D Zaman K fakhar A h Kara Department of Mathematical Sciences King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mathematics Faculty of ScienceUniversiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia Ibnu Sina Institute for fundamental Science Studies Universiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia School of Mathematics University of the WitwatersrandJohannesburgWits 2050South Africa

first,we studied the invariance properties of the Kadomstev–Petviashvili equation with power law ***,we determined the complete class of conservation laws and stated the corresponding conserved densities which are useful in finding the conserved quantities of the *** point symmetry generators were also used to reduce the equation to an exact solution and to verify the invariance properties of the conserved flows.

关键词： equation conserved equation

Rational Solutions of first Order Algebraic Ordinary Differential Equations

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第2期37卷 567-580页

作者： fENG Shuang shen Liyong School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n )a_(i)(t,y)y'^(i)=0 be an irreducible first order ordinary differential equation with polynomial *** in 1998 proved that there exists a constant C such that every rational solution of f(t,y,y')=0 is of degree not greater than *** show that this degree bound C depends not only on the degrees of f in t,y,y' but also on the coefficients of f viewed as the polynomial in t,y,y'.In this paper,the authors show that if f satisfies deg(f,y)f,y')or n max i=0{deg(a_(i),y)−2(n−i)}>0,then the degree bound C only depends on the degrees of f in t,y,y',and furthermore we present an explicit expression for C in terms of the degrees of f in t,y,y'.

关键词： Degree bound first order AODE height rational solution

Pyrometallurgical recycling of spent lithium-ion batteries from conventional roasting to synergistic pyrolysis with organic wastes

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第10期85卷 547-561,I0014页

作者： Chao Pan Yafei shen China Energy Science and Technology Research Institute Co.Ltd. Nanjing 210023JiangsuChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC) Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044JiangsuChina

The synergistic pyrolysis has been increasingly used for recycling spent lithium-ion batteries(LIBs)and organic wastes(hydrogen and carbon sources),which are in-situ transformed into various reducing agents such as h_(2),CO,and char via carbothermal and/or gas thermal *** with the conventional roasting methods,this“killing two birds with one stone”strategy can not only reduce the cost and energy consumption,but also realize the valorization of organic *** paper concluded the research progress in synergistic pyrolysis recycling of spent LIBs and organic *** the one hand,valued metals such as Li,Co,Ni,and Mn can be recovered through the pyrolysis of the cathode materials with inherent organic materials(e.g.,separator,electrolyte)or graphite *** the pyrolysis process,the organic materials are decomposed into char and gases(e.g.,CO,h_(2),and Ch_(4))as reducing agents,while the cathode material is decomposed and then converted into Li_(2)CO_(3) and low-valent transition metals or their oxides via in-situ thermal *** formed Li_(2)CO_(3) can be easily recovered by the water leaching process,while the formed transition metals or their oxides(e.g.,Co,CoO,Ni,MnO,etc.)can be recovered by the reductant-free acid leaching or magnetic separation *** the other hand,organic wastes(e.g.,biomass,plastics,etc.)as abundant hydrogen and carbon sources can be converted into gas(e.g.,h_(2),CO,etc.)and char via *** cathode materials are decomposed and subsequently reduced by the pyrolysis gas and *** addition,the pyrolysis oil and gas can be upgraded by catalytic reforming with the active metals derived from cathode ***,great challenges are proposed to promote this promising technology in the industrial applications.

关键词： Synergistic pyrolysis Spent LIBs Biomass Recycling Reduction roasting

high strength-superplasticity combination of ultrafine-grained ferritic steel:The significant role of nanoscale carbides

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第24期83卷 131-144页

作者： J.W.Liang Y.f.shen R.D.K.Misra P.K.Liaw Key Laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang110004China The State Key Lab of Rolling&Automation Northeastern UniversityShenyang110819China Laboratory for Excellence in Advanced Steel Research University of Texas at El PasoTX79968USA Department of Materials Science and Engineering University of TennesseeKnoxvilleTN37996USA

There is currently a gap in our understanding of mechanisms that contribute to high strength and high plasticity in high strength UfG ferritic steel with nano-size fe3 C carbides in situations that involve combination of various strain rates and high *** this regard,we describe the mechanistic basis of obtaining high strength-high plasticity combination in an ultrafine-grained(UfG)(~500±30 nm)ferritic steel with nano-size carbides,which sustained large plastic deformation,exceeding 100%elongation at a temperature significantly below 0.5 of the absolute melting point(Tm).To address the missing gap in our knowledge,we conducted a series of experiments involving combination of strain rate and temperature effects in conjunction with electron microscopy and atom probe tomography(APT).Strain rate studies were carried out at strain rates in the range of 0.0017-0.17 s^(-1)and at different temperatures from 25℃to 600℃.Dynamic recrystallization occurred at 600℃,resulting in a significant decrease in yield and tensile ***,the UfG ferritic steels had an advantage in tensile strength(UTS)and elongation-to-failure(εf)at 600℃,especially at strain rate of 0.0017 s^(-1),with high UTSof 510 MPa and excellent low temperature(f=110%).These mechanical properties are significantly superior compared to similar type of steels at identical temperature.A mechanistic understanding of mechanical behavior of UfG ferritic steels is presented by combining the effect of strain rate,temperature,and nano-size carbides.

关键词： UfG ferritic steel Strain rate Temperature Nano-size precipitate Low temperature superplasticity