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REsEARCH ON HOT FORMING PROCEss OF A RETAINING RING OF HIGH-NITROGEN sTEEL

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Acta Metallurgica sinica(English Letters) 2004年第5期17卷 767-770页

作者： H.q.Chen J.s.Liu H.G.Guo DepartmentofMaterialscienceandEngineering TaiyuanHeavyMachineryInstituteTaiyuan030024China

Mn18Cr18N, the high-nitrogen steel, is the 2nd generation material for manufacturing the retaining ring of firepower generators. In this paper, the hot deformation behavior of the material was investigated by thermo-mechanical modeling tests. And the flow stress curves of the steel were obtained for various combinations of the temperature and strain rate. Based on the results of the tests, the complex forming process of a retaining ring including punching, expanding and extrusion with an enclosure was put forward and simulated by means of numerical simulation method. The results indicate that the process is a novel and force-saved practical technology for manufacturing heavy retaining rings.

关键词： Mn18Cr18N high-nitrogen steel a retaining ring the punching with an enclosure process expanding-extrusion complex forming

Hybrid Excited Permanent Magnet Machines for Electric and Hybrid Electric Vehicles

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CEs Transactions on Electrical Machines and systems 2019年第3期3卷 233-247页

作者： Z.q.Zhu s.Cai Department of Electronics and Electrical Engineering University of SheffieldSheffieldS13JD U.K

This paper reviews various hybrid excited(he)machines from the perspective of location of PM and DC excitation,series/parallel connection of PM and DC excited magnetic fields,and 2D/3D magnetic fields,*** advantages as well as drawbacks of each category are *** an additional control degree,*** excitation,is introduced in the he machine,the flux weakening control strategies are more *** flux weakening performance as well as efficiency are compared with different control ***,the potential to mitigate the risk of uncontrolled overvoltage fault at high speed operation is highlighted by controlling the field *** additional DC coils are usually required for he machines compared with pure PM excitation,the spatial confliction inevitably results in electromagnetic performance ***,the technique to integrate the field and armature windings with open-winding drive circuit is introduced,and novel he machines without a DC coil are summarized.

关键词： Electric vehicle(EV) flux weakening control hybrid electric vehicle(heV) hybrid excited(he)machine open-winding permanent magnet(PM).

PERsPECTIVEs IN MECHANICs OF heTEROGENEOUs sOLIDs

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Acta Mechanica solida sinica 2011年第1期24卷 1-26页

作者： C.q. Chen J.Z. Cui H.L. Duan X.q. Feng L.H. he G.K. Hu M.J. Huang Y.Z. Huo B.H. Ji B. Liu X.H. Peng H.J. shi q.P. sun J.X. Wang Y.s. Wang H.P. Zhao Y.P. Zhao q.s. Zheng W.N. Zou Department of Engineering Mechanics AML Tsinghua University Beijing 100084 China Academy of Mathematics and systems sciences Chinese Academy of Sciences Beijing 100190 China state Key Laboratory for Turbulence and Complex system and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China CAs Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230026 China school of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced study Nanchang University Nanchang 330031 China Depariment of Mechanics and Engineering sciences Fudan University 220 Handa Road Shanghai 200433 China Department of Mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of Mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China state Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The Micro- and Nano-mechanics Working Group of the Chinese society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica solida sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica solida sinica, its editor-in-chief, Professor q.s. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

ELECTROCheMICAL IMPEDANCE sPECTROsCOPY DURING CORROsION PROCEss OF 8090 Al-Li ALLOY IN EXCO sOLUTION

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Acta Metallurgica sinica(English Letters) 2004年第6期17卷 894-901页

作者： J.F.Li Z.q.Zheng C.Y.Tan s.C.Li Z.Zhang J.q.Zhang CollegeofMaterialsscienceandEngineering CentralSouthUniversityChangsha410083China／／DepartmentofChemistryZhejiangUniversityHangzhou310027China CollegeofMaterialsscienceandEngineering CentralSouthUniversityChangsha410083China DepartmentofChemistry ZhejiangUniversityHangzhou310027China DepartmentofChemistry ZhejiangUniversityHangzhou310027China／／StateKeyLaboratoryforCorrosionand.ProtectionInstituteofMetalResearchTheChineseAcademy

The corrosion behavior and electrochemical impedance spectroscopy (EIs) features of 8090 Al-Li alloys in EXCO solution were investigated, and the EIs was simulated using an equivalent circuit. At the beginning of immersion in EXCO solution, the EIs is comprised by a depressed capacitive arc at high-mediate frequency and an inductive arc at low frequency, and the inductive component decreases and disappears with im- mersion time. Once exfoliation or severe pitting corrosion is produced, two capacitive arcs appear in the EIs. These two capacitive arcs are originated from the two parts of the corroded alloy surface, the original flat alloy surface and the new inter-face exposed to the aggressive EXCO solution due to the exfoliation or pitting corrosion. some corrosion development features of 8090 Al-Li alloys in EXCO solution can be obtained through simulated EIs information.

关键词： Al-Li alloy, exfoliation, electrochemical impedance spectros- copy (EIs), EXCO solution

study of magnetic and optical properties of Zn1-xTMxTe(TM = Mn,Fe,Co,Ni) diluted magnetic semiconductors：First principle approach

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Chinese Physics B 2017年第2期26卷 452-460页

作者： q Mahmood M Hassan M A Faridi Department of Physics University of the Punjab Quaid-e-Azam Campus-54590 Lahore Pakistan Centre for High Energy Physics University of the Punjab Lahore Pakistan

We present structural,magnetic and optical characteristics of Zn_（1-x）TM_xTe（TM = Mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） *** optimization of the crystal structures have been done to compare the ferromagnetic（FM） and antiferromagnetic（AFM） ground state energies,to elucidate the ferromagnetic phase stability,which further has been verified through the formation and cohesive ***,the estimated Curie temperatures T_c have demonstrated above room temperature ferromagnetism（RTFM） in Zn_（1-x）TM_xTe（TM =Mn,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that Mn- and Co-doped ZnTe behave as ferromagnetic semiconductors,while half-metallic ferromagnetic behaviors are observed in Fe- and Ni-doped *** presence of ferromagnetism is also demonstrated to be due to both the p-d and s-d hybridizations between the host lattice cations and TM *** calculated band gaps and static real dielectric constants have been observed to vary according to Penn＇s *** evaluated band gaps lie in near visible and ultraviolet regions,which make these materials suitable for various important device applications in optoelectronic and spintronic.

关键词： magnetic semiconductors density functional theory optical and dielectric properties electron density of states and band structure of crystalline solids

Advances in computational ChlA-PET data analysis

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Frontiers of Electrical and Electronic Engineering in China 2016年第3期4卷 217-225页

作者： Chao he Guipeng Li Diekidel M. Nadhir Yang Chen Xiaowo Wang Michael q. Zhang MOE Key Laboratory of Bioinformatics and Bioinformatics Division TNLIST Center for Synthetic and Systems Biology/ Department of Automation Tsinghua University Beijing 100084 China Departmeni of Biological sciences Cenier for SystemsBio/ogy ihe University of Texas at Dallas Richardson TX 75080-3021 USA

Genome-wide chromatin interaction analysis has become important for understanding 3D topological structure of a genome as well as for linking distal cis-regulatory elements to their target genes. Compared to the Hi-C method, chromatin interaction analysis by paired-end tag sequencing （ChlA-PET） is unique, in that one can interrogate thousands of chromatin interactions （in a genome） mediated by a specific protein of interest at high resolution and reasonable cost. However, because of the noisy nature of the data, efficient analytical tools have become necessary. here, we review some new computational methods recently developed by us and compare them with other existing methods. Our intention is to help readers to better understand ChlA-PET results and to guide the users on selection of the most appropriate tools for their own projects.

关键词： Genome computational methods interest Consumers topological structure Unique Chromatin High definition

sTRENGTheNING CAsT IRON MATRIX BY ALLOYINGELEMENTs WITH POsITIVE AND NEGATIVEsEGREGATION

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Acta Metallurgica sinica(English Letters) 1997年第4期10卷 329-332页

作者： Fan, Z.K. Wang, Y.q. Liang, s.H. Huang, H.s. Xi'an Univ of Technology Xi'an China

The combinational use of alloying elements with positive and negative segregation has been shown to be very effective in strengthening the matrix of cast iron. Negative segregation alloying elements, Cu and si, make the inner parts of dendritic austenites and eutectic cells get good hardenability. On the contrary, positive segregation alloying elements Cr and Mn make the outer parts of dendrites have higher microhardness. Appropriate combination of the above two types of alloying elements can produce a uniform microhardness and high strength in gray cast irons.

关键词： Cast iron Chromium Copper Hardness Manganese segregation (metallography) silicon strengthening (metal)

TGF-b:the sword,the wand,and the shield of FOXP3^(+)regulatory T cells

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Journal of Molecular Cell Biology 2012年第1期4卷 29-37页

作者： Dat q.Tran Division of Pediatric Research Center Department of PediatricsThe University of Texas Medical School at HoustonHoustonTX 77030USA

since its rediscovery in the mid-1990s,FOXP31 regulatory T cells(Tregs)have climbed the rank to become commander-in-chief of the immune *** possess diverse power and ability to orchestrate the immune system in time of inflammation and infection as well as in time of harmony and *** be the commander-in-chief,they must be equipped with both offensive and defensive *** review will focus on the function of transforming growth factor-b(TGF-b)as the sword,the wand,and the shield of *** as a sword,this review will begin with a discussion of the evidence that supports how Tregs utilize TGFb to paralyze cell activation and differentiation to suppress immune *** will next provide evidence on how TGF-b from Tregs acts as a wand to convert naıve T cells into iTregs and Th17 to aid in their combat against inflammation and ***,the review will present evidence on the role of TGF-b produced by Tregs in providing a shield to protect and maintain Tregs against apoptosis and destabilization when surrounded by inflammation and constant *** triadic function of TGF-b empowers Tregs with the responsibility and burden to maintain homeostasis,promote immune tolerance,and regulate host defense against foreign pathogens.

关键词： Foxp3 TGF-b LAP LRRC32 GARP Tregs autoimmunity tolerance transplantation

Long-term corrosion evolution associated with the structural heterogeneities of an Fe-based amorphous coating in H_(3)BO_(3)solution at various temperatures

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Journal of Materials science & Technology 2023年第9期140卷 233-248页

作者： D.B.Wang J.Wu J.P.Cui q.Wang T.R.Li W.Emori s.D.Zhang J.q.Wang shenyang National Laboratory for Materials science Institute of Metal ResearchCASShenyang110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Biorheological science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing400044China school of Materials science and Engineering Sichuan University of Science and EngineeringZigong 643000SichuanChina

Understanding the long-term corrosion behavior of neutron absorber materials in H_(3)BO_(3)solution is crucial for the materials applications in spent fuel *** this paper,long-term corrosion evolution for 180 d in relation to the structural heterogeneities of an Fe-based amorphous coating(AMC)in H_(3)BO_(3)solution at various temperatures was systematically *** indicate that the coating corrosion could be divided into three distinct ***,the corrosion resistance increased owing to the thickening and composition evolution of the passive ***,the corrosion rate was kept almost constant in the second stage,which connected with the steady state of the passive ***,the corrosion resistance of coating reduced gradually owing to the initiation and penetration of local-ized ***,it was revealed that the localized corrosion was initiated at the relatively Cr-depleted amorphous matrix in the deep pores of the *** could be attributed to the synergy of Cr-depletion and occlusive effect in the deep pores during long-term *** the elevation of temperature,the localized corrosion was enhanced due to the accumulation of the H+in the pores to swiftly reach the critical conditions for passive film *** work provides insights into the long-term corrosion mechanism of Fe-based AMCs in H_(3)BO_(3)solution and offers meaningful contributions to the design of new corrosion resistant neutron absorbing coatings for spent fuel storage applications.

关键词： AMC Boric acid EIs Long-term corrosion Temperature