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Mechanical Model on Brittle Crack Initiation and Propagation

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Journal of Materials Science & Technology 1996年第5期12卷 353-356页

作者： Han, GW feng, d Ye, WJ Luo, HL dept. of Superalloy Central Iron and Steel Research Institute Beijing 100081 China

A mechanical model is presented in this paper to describe the initiating and propagating of brittle cracks. Two criteria have been deduced from the model to determine the effects of such factors as local stress state, surface and grain boundary energies as well as local grain boundary orientation on the initiating and propagating of both intergranular and transgranular brittle cracks. By which the role of adding B in Ni3Al base alloys to improve their ductility temper and hydrogen embrittlements in steels and other alloys as well as the random feature of brittle crack initiation could be explained.

关键词： Crack initiation

Investigation on the Recrystallization Behaviour of Cold deformed MP159 Alloy

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Journal of Materials Science & Technology 1996年第4期12卷 277-280页

作者： Han, GW feng, d Yin, M Ye, WJ Luo, HL dept. of Superalloys Central Iron and Steel Research Institute Beijing 100081 China

The recrystallization behaviour of cold drawn MP159 alloy was investigated by optical and TEM examinations. It is found that the platelet epsilon phase in the MP alloy inhibits the recrystallization, and this effect makes the MP159 alloy with high recrystallization temperature of about 920 degrees C. This inhibition mainly comes from the increasing of the interfacial energy, which results from the change of the coherent interfaces of (0001)(hcp)//(111)(fcc) into the incoherent interfaces when the recrystallizing grain fronts bypass the platelet epsilon martensite. The increasing of the interfacial energy also causes the dissolution of a few segments on the epsilon martensite platelets, which decreases the strength of the MP alloy.

关键词： Cobalt alloys

The associations between Parkinson’s disease and cancer: the plot thickens

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Translational Neurodegeneration 2015年第1期4卷 160-173页

作者： danielle d.feng Waijiao Cai Xiqun Chen MassGeneral Institute for Neurodegenerative disease Department of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA department of Epidemiology Harvard T.H.Chan School of Public HealthBostonMAUSA Key Laboratory of Cellular and Molecular Biology Huashan HospitalFudan UniversityShanghai 200040China

Epidemiological studies support a general inverse association between the risk of cancer development and Parkinson’s disease(Pd).In recent years however,increasing amount of eclectic evidence points to a positive association between Pd and cancers through different temporal analyses and ethnic *** positive association has been supported by several common genetic mutations in SNCA,PARK2,PARK8,ATM,p53,PTEN,and MC1R resulting in cellular changes such as mitochondrial dysfunction,aberrant protein aggregation,and cell cycle ***,we review the epidemiological and biological advances of the past decade in the association between Pd and cancers to offer insight on the recent and sometimes contradictory findings.

关键词： cancer PARK thick

dRYING OF GRANULAR MATERIALS IN AGITATEd FLUIdIZEd BEd

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Journal of Hydrodynamics 2001年第2期13卷 29-31页

作者： Ma, J.H. Liu, H. feng, d.Z. dept. of Air-Condition Eng. Shandong Inst. of Civil Eng. Jinan 250014 China

An experimental study of the drying characteristics of an agitated fluidized bed dryer is presented and discussed. In the study, the citric acid particles were used as bed material with the diameters ranging from 0.2 mm to 1.3 mm. The variables affecting apparently the drying rate were found to be the mass flow rate, the inlet air temperature, the rotary speed of agitating mechanism and the particles feed rate. Comparing with other variables considered, mass flow rate was found to have the least important influence on the drying rate. The agitated fluidized bed dryer is suitable to drying agglomerating or sticky materials.

关键词： dryers (equipment) drying Experiments Mass transfer

INTERMETALLICS AS SUBSTITUTES FOR SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 463-467页

作者： J. Zhang d. feng Z. Y. Zhong High Temperature Materials division Central Iron and Steel Research Institute Beijing 100081China

The application advances of TiAl, Ti3Al and Ni3Al base aUoys were denumstrated by Central Iron and Steel Research Institute, China. The recent research progresses on improving the reliability of cast TiAI were mainly presented and discussed. The characteristics of the self-oriented lamellar microstructure in cast TiAI were investigated in both as cast and as HlPed states. Based on the mechanical anisotropy of the cast lamellar microstructure, the component specific microstrueture design was proposed for a better performance and reliability of cast TiAl.

关键词： intermetallic application TiAl alloy microstructure design

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一种基于标记的并行细化算法

电子学报 2000年第11期28卷 9-11页

作者：任金昌赵荣椿 david d.feng 西北工业大学计算机系西安710072 香港理工大学电子及资讯工程学系中国香港悉尼大学计算机系澳大利亚

本文提出了一种基于图像标记的并行细化算法 .首先计算图像中像素和轮廓距离的标记信息 ,并将标记图像作为细化算法的输入 .通过综合利用标记信息 ,保留了几何特性 ,提高了细化算法的鲁棒性 ,同时为进一步图元识别

关键词：图像标记并行细化轮廓距离计算机图像处理

A novel method for AFRPs burrs removal:Principle of mechanochemo-induced fiber fracture

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Chinese Journal of Aeronautics 2024年第7期37卷 522-538页

作者： Jie XU Bo LI Pingfa feng Qiang WANG feng feng division of Advanced Manufacturing Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Changhe Aircraft Industry(Group)Co.Ltd Jingdezhen 333000China

Burrs generated during the machining of Aramid-Fiber-Reinforced Composites(AFRPs)pose a challenge for the production efficiency of aircraft and helicopter housing *** studies have generally attempted to suppress burrs by referring to delamination suppression *** contrast to stratification,burrs are remediable machining *** such,a mechanochemical method with burrs trimming technological strategy are implemented to effectively combat ***,we clarify the mechanism by which aramid fibers cannot be cut off using analytical and numerical *** addition,the mechanism of fiber fracture with Modified Polyurethane Reactive Polymer(M-PUR),and development of anti-burr devices(thermostatic adhesive sealed generator)are ***,the experimental results show that the reduction rate in burr length is 87%-91%through the mechanochemical *** method not only opens a new avenue to solve the burr problem of aramid fibers but also builds an interdisciplinary bridge between polymer science and composite machining.

关键词： Mechanochemical method Burrs Orthogonal cutting Aramid fiber-reinforced composites Milling

Uncovering Microstructure-Property Relationship in Ni-Alloyed Fe-Mn-Al-C Low-density Steel Treated by Hot-Rolling and Air-Cooling Process

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 713-725页

作者： Xiaoliang Jia Guhui Gao Xiaolu Gui Chun feng R.d.K.Misra Bingzhe Bai School of Mechanical Electronicand Control EngineeringBeijing Jiaotong UniversityBeijing100044China CNPC Tubular Goods Research Institute Xi’an710077China Laboratory for Excellence in Advanced Steel Research University of Texas at El PasoEl PasoTX79968-0521USA School of Material Science and Engineering Key Laboratory of Advanced Materials of Ministry of EducationTsinghua UniversityBeijing100084China

This paper focuses on the relationship between the microstructure and tensile properties of Fe-Mn-Al-C low-density high-strength steel processes by hot-rolling and air-cooling process. The microstructure analysis reveals that the combination of hot-rolling and air-cooling results in the formation of heterogeneous structures comprising different-sized γ and B_(2) phases in the low-density steel with the addition of nickel (Ni). The addition of Ni promotes the formation of the B_(2) phase and induces the pinning of B_(2) phase particles at the γ grain boundaries. This pinning effect effectively hinders the growth of the γ grains, leading to grain refinement. The tensile test results demonstrate that LdS-5Ni (low-density steel, LdS) exhibits excellent high strength and ductility combination, e.g., a tensile strength of 1535 MPa, yield strength of 1482 MPa, and elongation of 23.3%. These remarkable mechanical properties are primarily attributed to the combined strengthening contributions of grain refinement and duplex nano-sized second-phase precipitation hardening.

关键词： Low-density steel Microstructure B_(2)phase κ-Carbide Tensile properties

Record-high efficiency perovskite LEds achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： feng Gao department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEds)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEds in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

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