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Flow Uniformity of Roller-Type Quenching Machine

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Journal of Iron and Steel Research International 2010年第7期17卷 24-27页

作者： zhu dong-mei LIU Guo-yong ZHANG Shao-jun LI Mou-wei School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

Three-dimensional finite element flow field model of spraying pipe of roller-type quenching machine is *** flow field with different structural parameters is *** grouping the nozzles,the spraying uniformity is analyzed under the conditions of different water inlet pipe diameter,different water inlet pipe distance,nozzle diameter and nozzle *** the spraying intensity absolute deviation and relative deviation are computed under different *** effect of different structural parameters on cooling uniformity is *** results provide theoretical basis for improving production quality and optimizing cooling device design.

关键词： roller-type quenching machine uniform cooling structural parameter

Study on Microwave Dielectric Property of Carbon Black and Short Carbon Fibers

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Chinese Journal of Aeronautics 2006年第B12期19卷 130-133页

作者： WUHong-huan zhu dong-mei LUO Fa ZHOU Wan-cheng WANG Xiao-yan State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

Carbon black and carbon fibers of different lengths were introduced in different matrices at different ratios to explore their microwave dielectric properties under 8.2 GHz-12.4 GHz. It is found that the actual dielectric constants of the samples containing carbon black are in a two-order function of the contents of carbon black （ε＇, ε＂=Av2＋Bv＋C） and the complex dielectric constants show an obvious frequency response. Of the added fibers of different lengths, the 4 mm-long one could well disperse in the matrices having not only good frequency response, but also larger real parts, imaginary parts and loss values. The imaginary parts and the loss values （tanδ）of the samples with 4 mm-long carbon fibers added increase linearly with the contents of fiber increasing. So it is practicable to adjust the dielectric parameters of the material in a wide range by changing the added amount of carbon black, and the carbon fiber or altering the lengths of the carbon fiber added.

关键词： microwave dielectric property short carbon fibers carbon black

Numerical analysis of grinding power consumption of a vertical planetary mill

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Journal of China University of Mining and Technology 2008年第2期18卷 311-315页

作者： HAO Xue-di zhu dong-mei BIAN Zhi-rui WANG Xin School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China School of Mechanical Engineering Hebei Polytechnic University Tangshan Hebei 063009 China

Planetary wheel rolling on a coal-bed was simplified as rigid wheel rolling on the coal-bed with a rigid base when a Ver- tical planetary mill(VPM)is *** on our analysis,we conclude that the Bekker formulation for computing rolling resis- tance is not applicable to calculate directly the rolling resistance of the *** to the principle of the Bekker apparatus,pressure-sinkage curves were obtained by tests on a piece of mono-axial consolidation apparatus used in *** de- formation modulus of the coal-bed was calculated using elastic mechanics.A finite element model of the planetary wheel coal-bed was built up by the use of a rigid and a Drucker-Prager material model in *** to the simulation results,the wheel rolling resistance,the grinding power consumption and the motor power of the mill were calculated and the mistake in the initial design of the mill was *** simulation results agree well with the results of the semi-industrial tests.

关键词： VPM power-consumption grinding rolling finite element method (FEM)

On the Quasi-monotonic Problem

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Chinese Quarterly Journal of Mathematics 2006年第3期21卷 461-464页

作者： zhu dong-mei WANG Zhi-guo Department of Basic Course Yellow River Conserrancy Technical Institute Kaifeng 475001 China College of Mathematics and Information Sciences Henan University Kaifeng 475001 China

This paper gives the necessary condition and one sufficient condition of the quasimonotonic function, and proves that the linear fractional function is quasi-monotone.

关键词： quasi-monotone necessary condition sufficient condition linear fractional function

Effect of MoSi_2 content on dielectric and mechanical properties of MoSi_2/Al_2O_3 composite coatings

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Transactions of Nonferrous Metals Society of China 2012年第1期22卷 111-116页

作者： WU Zhi-hong ZHOU Wan-cheng LUO Fa zhu dong-mei State Key Laboratory of Solidification Processing Northwestem Polytechnical UniversityXi’an 710072China

Molybdenum disilicide （MoSi2） sheath and aluminum oxide （Al2O3） core blended powders were fabricated by spray drying. A derived coating material was produced for the application as microwave absorbers using the as prepared powders by atmospheric plasma spray （APS） technology. The effects of MoSi2/Al2O3 mass ratio on the dielectric and physical mechanical properties of the composite coatings were investigated. When the MoSi2 content of the composites increases from 0 to 45%, the flexure strength and fracture toughness improve from 198 to 324 MPa and 3.05 to 4.82 MPa-m1/2 then decline to 310 MPa and 4.67 MPa-m1/2, respectively. The dielectric loss tangent increases with increasing MoSi2 content, and the real part of permittivity decreases conversely over the frequency range of 8.2-12.4 GHz. These effects are due to the agglomeration of early molten MoSi2 particles and the increase of the electrical conductivity with increasing MoSi2 content.

关键词： MoSi2/Al2O3 composite coating atmospheric plasma spraying mechanical properties dielectric properties

ANOMALOUS STRAIN RATE DEPENDENCE OF FLOW STRESS IN TiAl INTERMETALLIC COMPOUNDS

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Acta Metallurgica Sinica(English Letters) 1992年第5期5卷 390-394页

作者： WANG Liming zhu dong YAO mei CAI Qigong ZOU Dunxu State Key Laboratory for Fatigue and Fracture of Materials,Academia Sinica,Shenyang Central Iron and Steel Research Institute,Ministry of Metallurgical Industry,Beijing,China State Key Lab for Fatigue and Fracture of Materials Acad Sinica Shenyang China

Plastic deformation of TiAI and TiAI-V intermetallic compounds has been studied by com- pression experiment at various temperatures and strain *** show that the plastic deformation in distinct temperature range is principally controlled by the mechanisms of Peierls-Nabarro,cross slip and creep of *** TiAI-V alloy deformed at a range of 600—700 K,the negative strain rate dependence of flow stress was observed,i.e.,the more the plastic strain *** more the negative dependence will be.A possible mechanism of the anomaly could be interpreted by thermal activation of dislocation cross *** effects of temperature and strain rate on work-hardening exponent were also studied and discussed.

关键词： TiAl intermetallic compound strain rate cross-slip

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一类非线性时滞差分方程解的渐近性质

山东大学学报（自然科学版） 2000年第1期35卷 34-40页

作者：朱冬梅山东大学数学院山东济南250100

研究一类非线性时滞差分方程的解的渐近性质 ,给出方程的解收敛于常数的结果 .

关键词：非线性时滞差分方程渐近性质解时滞微分方程

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LASEK治疗近视疗效观察

眼外伤职业眼病杂志 2005年第5期27卷 361-363页

作者：朱冬梅郑州市第五人民医院卓美眼科中心河南郑州450003

目的　评价LASEK治疗近视的早期疗效。方法　对41例(81眼)不同屈光度(-2 . 75D～-14 . 0 0D)的近视进行LASEK手术,观察术中术后并发症,并对术后1～6月裸眼视力、屈光状态及角膜上皮下雾状浑浊(haze)进行随访。结果　2例(4眼)Ⅰ级haze... 详细信息

目的　评价LASEK治疗近视的早期疗效。方法　对41例(81眼)不同屈光度(-2 . 75D～-14 . 0 0D)的近视进行LASEK手术,观察术中术后并发症,并对术后1～6月裸眼视力、屈光状态及角膜上皮下雾状浑浊(haze)进行随访。结果　2例(4眼)Ⅰ级haze ,3月时视力低于术前矫正视力1～3行,为轻度近视状态(-0 . 75D～-3 . 2 5D)。1例(2眼)Ⅱ级haze ,3月视力下降,屈光回退。6月回退到术前屈光状态。其余病例6月时视力均在0 . 5以上,达1 0者62眼占总复诊人数(76眼)的81 . 5 8%。屈光稳定于±1 . 0D以内,haze 0～0 . 5级者70眼占复诊人数(76眼)的92 . 11%。结论　LASEK是治疗近视有效方法之一,但也存在明显并发症。

关键词：近视激光上皮下角膜磨镶术角膜上皮下雾状浑浊

基于温度-组织-应力三场耦合的耐磨钢淬火工艺

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材料热处理学报 2015年第3期36卷 232-237页

作者：朱冬梅张少军李超沈洋北京科技大学机械工程学院北京100083

通过实验测定了TNM360耐磨钢在20~900℃范围内的比热容和热导率;测定了耐磨钢的等温转变曲线(TTT曲线)以及100~1000℃之间每隔100℃的真应力真应变曲线以及马氏体相变膨胀曲线,计算得出马氏体转变相关系数;针对10 mm厚耐磨钢板,设计3种... 详细信息

通过实验测定了TNM360耐磨钢在20~900℃范围内的比热容和热导率;测定了耐磨钢的等温转变曲线(TTT曲线)以及100~1000℃之间每隔100℃的真应力真应变曲线以及马氏体相变膨胀曲线,计算得出马氏体转变相关系数;针对10 mm厚耐磨钢板,设计3种淬火冷却工艺:第一与第二冷却工艺相比,钢板运行速度相同,冷却器开启组合不同;第一与第三冷却工艺相比,冷却器开启组合相同,而钢板运行速度不同。并利用Ansys和Matlab对冷却过程的温度场、组织场以及应力场进行模拟计算。结果表明:TNM360耐磨钢3种工艺终冷温度均在技术要求范围内,终冷后组织均为马氏体及少量残留奥氏体,但在冷却器全开,钢板运行速度为1.6 m/s,淬火后残余应力及应变最小,板形最好。

关键词：耐磨钢三场耦合淬火工艺数值模拟