检索结果-南通市图书馆

Surface Temperature Change of U75V 60 kg/m Heavy Rail During Heat Treatment

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2013年第2期20卷 33-37,67页

作者： KANG Hao WU Di zhao xian-ming State Key Laboratory of Rolling and Automation Northeastern University

The U75V 60 kg/m heavy rail samples were heated to 900 ℃ in a resistance furnace for a fixed duration of 50 min. Under this condition, the samples were austenitized totally. Then, the samples were dragged out of furnace and cooled for 25 s in the open air. After that, the samples entered into the air spraying channel, and were cooled from the top and both sides by compressed air. During this period, main technical parameters were changed such as the distance between spray nozzles and surface of rail head, air pressure, air spraying time and air temperature. So under laboratory condition, optimal heat-treating parameters of U75V 60 kg/m heavy rail were determined as the distance between spray nozzles and surface of rail head of 15 mm, air pressure of 0.26 MPa, cooling time of 80 s, and air temperature of 28 ℃. The surface temperature at different positions of heavy rail was measured before and after heat treatment, and the temperature changing law was determined. The self tempering occurred on the surface of rail head after heat treatment, and the tempering temperature became the largest （about 3 min） after heat treatment, separately 528, 524 and 536 ℃ at the center, top fillet and bottom fillet of rail head. The heavy rail was cooled in open air after heat treatment; during this period, the temperature gap on the surface of heavy rail became smaller and smaller, and was reduced to zero when being cooled for 20 min.

关键词： temperature change heavy rail heat treatment

Modeling of Austenite Decomposition in Low Si-Mn TRIP Steel During Cooling

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2008年第6期15卷 68-71页

作者： ZHU Li-juan WU Di zhao xian-ming College of Materials Science and Engineering Jilin University Changchun 130025 Jilin China The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

Transformation behavior in low carbon Si Mn TRIP steel was investigated by means of microstructural ob servation and computer modelling. A transformation model in which transformation is controlled by carbon diffusion was suggested, which well described the volume fractional change of ferrite, pearlite, and bainite during continuous cooling. The influence of Si content and austenite grain size was thoroughly investigated. The calculated results indicated that Si retards pearlite transformation, accelerates polygonal ferrite transformation, refines the austenite grain, and increases the ferrite transformation rate.

关键词： TRIP steel transformation incubation time ferrite bainite pearlite

Effect of Silicon Content on Thermodynamics of Austenite Decomposition in C-Si-Mn TRIP Steels

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2006年第3期13卷 57-60,73页

作者： ZHU Li-juan WU Di zhao xian-ming State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Some numerical models such as central atoms model （CAM） and superelement model were used to simulate the thermodynamics of austenite decomposition in the Fe-C-Mn-Si TRIP （transformation induced plasticity） steels. Thermodynamic calculations were carried out under a para-equilibrium （PE） condition. The results show that certain silicon content can accelerate the polygonal ferritic transformation and increase the volume fraction and stability of retained austenite by retarding the precipitation of carbides during the bainitic transformation.

关键词： central atoms model superelement model para-equilibrium austenite decomposition TRIP steel

Explicit Dynamic FEM Analysis of Multipass Vertical-Horizontal Rolling

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2006年第3期13卷 26-30页

作者： YU Hai-liang LIU xiang-hua zhao xian-ming WU Di Y. Kusaba State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Sumitomo Metal Industries Ltd Fuso-Cho 660 Amagasaki Japan

Three passes of plate rolling during vertical-horizontal rolling process are simulated with explicit dynamic finite element method and updating geometric method. The equivalent strain and stress fields, and shape change at the head and tail of slab during rolling are obtained. The calculated result of the shape at the head and tail of slab is in good agreement with the measured one. The explicit dynamic finite element method and updating geometric method can be used effectively to analyze the multipass vertical-horizontal （V-H） rolling process.

关键词： V-H rolling multipass equivalent stress strain slab shape

Effect of Controlled Cooling on Microstructure and Mechanical Properties of H-Beam

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2013年第8期20卷 60-65页

作者： GUO Fei zhao xian-ming WANG Li-na WU Di WANG Guo-dong NING Zhong-liang State Key Laboratory of Rolling and Automation Northeastern University Fushun New Iron and Steel Company Ltd.

Based on ANSYS, an analytical model was established for H beam during controlled cooling. The tempera-ture fields during controlled cooling and air cooling were analyzed and the microstructure and mechanical properties for different parts of H-beam were discussed in detail. After the H-beam was controlled cooled for 4.5 s, its mean surface temperature decreased from 850 to 460 ℃, and the lowest and the highest temperatures were measured at edge of flange and at R corner, respectively. Whereas, for the H-beam air cooled for 30 s, the mean temperature at R corner and web was 700 and 540 ℃, respectively. The microstructures for different parts of H-beam consisted of ferrite and pearlite, and the grain size at R corner was coarser than those at flange and web. The difference of yield and tensile strengths of web, flange and R corner was within 30 MPa, and the elongation was similar. The changes of microstructure were in good agreement with that of temperature field. In addition, the results show that the uni formity of microstructure and mechanical properties can be improved by increasing water flow rate at R corner.

关键词： H-beam controlled cooling air cooling temperature field microstructure mechanical property

Theoretical Design of Defects as a Driving Force for Ion Transport in Li3OBr Solid Electrolyte

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第3期7卷 147-157页

作者： Xingyun Luo Yanlu Li xian zhao State Key Lab of Crystal Materials and Institute of Crystal Materials Shandong University Center for Optics Research and Engineering Shandong University

Due to ever-increasing concerns about safety issues in using Li ionic batteries,solid electrolytes have extensively *** Li-rich antiperovskite Li3OBr has been considered as a promising solid electrolyte candidate,but it still suffers challenges to achieve a high ionic conductivity owing to the high intrinsic symmetry of the crystal ***,we presented a design strategy that introduces various point defects and grain boundaries to break the high lattice symmetry of Li3OBr crystal,and their effect and microscopic mechanism of promoting the migration of Li-ion were explored *** has been found that Liiare the dominant defects responsible for the fast Li-ion diffusion in bulk Li3OBr and its surface,but they are easily trapped by the grain boundaries,leading to the annihilating of the Frenkel defect pair V'Li+Li,and thus limits the V'Lidiffusion at the grain *** VBrdefect near the grain boundaries can effectively drive V'Liacross the grain boundary,thereby converting the carrier of Li+migration from Li,in the bulk and surface to V'Liat the grain boundary,and thus improving the ionic conductivity in the whole Li3OBr *** work provides a comprehensive insight into the Li+transport and conduction mechanism in the Li3OBr *** opens a new way of improving the conductivity for all-solid-state Li electrolyte material through the defect design.

关键词： defects density functional theory ionic migration solid electrolyte

Plasmon-enhanced ultra-high photoresponse of single-wall carbon nanotube/copper/silicon near-infrared photodetectors

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 5930-5936页

作者： Yi-ming zhao xian-Gang Hu Chao Chen Zuo-Hua Wang An-Ping Wu Hong-Wang Zhang Peng-xiang Hou Chang Liu Hui-ming Cheng Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China Faculty of Materials Science and Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Single wall carbon nanotube(SWCNT)/Si heterojunction photodetectors have the advantages of high photoresponse ability and simple structure,however,their detection wavelength range are usually lower than 1100 nm,which limits their application in the infrared *** report a SWCNT/Cu/Si photodetector with both a high photoresponse and a detection range up to the infrared band by depositing a Cu nanoparticles(NPs)layer between a SWCNT film and a n-Si *** was found that the Cu NPs produce strong surface plasmon resonance(SPR)under laser irradiation,which breaks through the limitation of Si band gap and greatly improves the photoresponse of the SWCNT/Cu/Si photodetector in the near infrared *** responsivity(R)of the photodetector in the wavelength range of 1850–1200 nm reached 2.2–14.15 mA/W,which is the highest value in the reported plasmon enhanced n-Si based photodetectors,and about 20,000 times higher than that of a SWCNT/Si *** R value for 1550 nm wavelength used in optical communications reached~8.2 mA/W,which is 64%higher than the previously reported values of commonly used *** attribute the significant increase to the strong SPR and low Schottky barrier of Cu with n-Si,which facilitates the generation and transfer of the carriers.

关键词： single wall carbon nanotube photodetector silicon surface plasmon resonance copper

Metal-organic nanosheet assembly ions sieving membrane for precise lithium ion and anion/solvent separation toward robust lithium metal battery

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

Science China Chemistry 2024年第10期67卷 3320-3327页

作者： Jian-Qiang Shen Tian-Tian zhao Ying-Li Song Lingjuan Zhang Ya-Nan Gao Xiao-Nan Cui Peng zhao xian-ming Zhang Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of EducationSchool of Chemistry & Material ScienceShanxi Normal University College of Chemistry and Chemical Engineering Taiyuan University of Technology

Metal-organic nanosheets（MONs） as a novel material with tunable pore structures and low mass transfer resistance,have emerged as molecular sieves for the separation of gases and *** theory,they can also serve as ion sieves for lithium metal batteries（LMBs）,realizing the high-energy and dendritic free ***,there are rarely relevant reports,because it is difficult to simultaneously balance efficient ion sieving ability,high ion passing rate and high electrochemical ***,we synthesized a stable ultrathin MON[Zn2（Bim）4]([Zn2（Bim）4]Nanosheet,HBim=benzimidazolate),which can achieve both efficient lithium ion sieving ability,high lithium ion passing rate and high electrochemical stability at the same *** separator assembled by this MON exhibits high Li+transfer number of 0.81 due to the accurate lithium ion and anion/solvent *** battery containing such separator shows high lithium ionic conductivity of 0.74 m S cm-1and low activation energy of 0.099 eV,which can be attributed to the nanometer level thickness and the ion sieving *** is more,we realized the application of MONs-based ion sieves in LMBs with intercalation cathodes for the first *** the LiFePO4|Li battery with as-assembled separator demonstrates improved Coulombic efficiency（>99%） and significantly extended cycling life（>1600 cycles） with 80% capacity retention.

关键词： lithium sieving membrane metal-organic nanosheets lithium metal battery lithium ion and anion separation lithium ion and solvent separation

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

赵先明辨治甲状腺癌术后的经验

中医肿瘤学杂志 2023年第1期5卷 48-52页

作者：黎颖娴段绍渊周淑怡赵先明广州中医药大学第一临床医学院广东广州510405 广州中医药大学第一附属医院二外科广东广州510405

甲状腺癌术后部分患者可出现咽部异物感、神疲乏力、食少纳呆、失眠多梦、心慌盗汗等不适症状,影响患者的日常生活,降低生活质量。赵先明认为甲状腺癌术后多本虚标实、虚实夹杂,常见证型为气滞痰凝、肝郁脾虚、气阴两虚,治疗以行气化痰... 详细信息

甲状腺癌术后部分患者可出现咽部异物感、神疲乏力、食少纳呆、失眠多梦、心慌盗汗等不适症状,影响患者的日常生活,降低生活质量。赵先明认为甲状腺癌术后多本虚标实、虚实夹杂,常见证型为气滞痰凝、肝郁脾虚、气阴两虚,治疗以行气化痰、疏肝健脾、益气养阴为法,并注重对脾胃的调养,在临床上取得较好的疗效。

关键词：甲状腺癌术后中医药治疗