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Damping Property of Supersaturated ZnA127Ce Alloy during Natural Aging

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Journal of Materials Science & Technology 2001年第1期17卷 9-10页

作者： Jingpei XIE Yaomin ZHU Yanpei SONG Xiaoying WANG and Quande CHEN dept.of Material engineering , Luoyang Institute of Technology, Luoyang 471039. China Dep. of Mater. Eng. Luoyang Inst. of Technol. Luoyang 471039 China

The microstructures and damping property of supersaturated ZnA127Ce alloy during natural aging have been investigated. H-800 TEM was mainly used to research the microstructures. The relationship between microstructure and damping property was primarily studied. The results showed that solution plus natural aging was the best heat treatment, which could improve the damping property. Both continuous precipitation and cellular reaction occurred during the aging. Continuous precipitation follows the sequence: β→spherical GP zones→elliptical GP zones→intermediate phase R→n. The cellular reaction can be written as follows:β→a+n+ε.

关键词： Ce Damping Property of Supersaturated ZnA127Ce Alloy during Natural Aging

THE　STATISTIC　CHARACTERISTICS　OF　IRREGULAR　BREAKING　WAVE　FORCES　ON　VERTICAL　WALLS

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Journal of Hydrodynamics 1995年第1期7卷 50-57页

作者： Li Yu-cheng Liu Da-zhong (dept.of Civil engineering,Dalian University of Technology,Dalian 116023, P. R. China) Dalian Univ of Technology Dalian China

When irregular waves attack a vertical wall, standing waves and breaking (or broken) waves will occur in front of the wall. The statistic characteristics of standing wave forces on vertical wall are the same as that of incident waves. But for breaking or broken waves, only large waves break, so the statistic characteristics of breaking wave forces are different to that of standing waves or incident waves. Following a series model test of irregular breaking waves on vertical wall the statistic characterisitics of breaking wave *** were analyzed in this paper. It is found by authors that Weibul distribution may be used to express the statistic distribution of breaking wave forces acting on vertical wall. msed on the analysis of model test data, it is indicated in this paper that the shape parameter m in Weibul distribution is a function of and , in which H is the wave height, d1 is the water depth at the toe of vertical wall and d is the water depth in front of the whole structure; and the theoretical value of scale parameter a can be determined from shape parameter m.

关键词： irregular waves breaking waves wave forces vertical wall.

A Microchip Tunable Blue Laser Source Based upon Cr∶LiSAF in Contact with KN Crystal

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Chinese Journal of Lasers 2002年第1期11卷 6-9页

作者： MENG Hongxiang (dept. of Optical engineering, Zhejiang University, Hangzhou 310027, China) HE Liangfang (dept. of Applied physics, Zhejiang University of Technology, Hangzhou 310014, China) dept. of Optical engineering Zhejiang University Hangzhou 310027 dept. of Applied physics Zhejiang University ofTechnology Hangzhou 310014

In this paper, a microchip laser consisted of 2.2% doped Cr∶LiSAF crystal and NCPM KN(KNbO 3) crystal and pumped by a 679 nm laser diode is reported. The maximal output of TEM 00 4.76 mW of blue laser at 431.7 nm is obtained with the absorption power of 304.6 mW. The laser shows a threshold of 76.2 mW and slope efficiency of 2.08%. Continuous-wave tunable output is demonstrated in the blue region of 423.4～445.5 nm through only changing temperature of KN crystal controlled by PID controller.

关键词： LD pumping intracavity double Cr∶LiSAF tunable blue lasers

Improvement real time performance of robot pose optic fiber sensor on screw assem blies

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光通信技术 1999年第4期 305-309页

作者： Li Xiufeng,Liu Guixiong (dept.of Machatronic engineering,South China University of Technology,Guangzhou,510640)

The paper firstly introduces screw direction detecting *** proposes a kind of neural network based parallel arithmetic in order to treat the circumstances of complicated sensing *** arithmetic can greatly enlarge the real time treatment ability of sensors,and is successively applied in the pose rectifying of robot screw flexible assembiles.

关键词： Optic fiber sensors BP network arithmetic Signal real time treatment

CUTTING TEMPERATURE OF TEMPERING BEARING STEEL GCr15 CUT BY PCBN CUTTER

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Chinese Journal of Mechanical engineering 1999年第4期12卷 254-259页

作者： Liu Xianli Chen Bo Meng An Chen Liguo Li Zhenjia dept.of Mechanism engineering, Harbin University of Science and Technology Yuan Zhejun Harbin Institure of Technology Harbin Univ of Science and Technology Harbin China

A thermoelectric curve of GCr15 BN500 is acquired by rapid label way. The study on measuring the cutting temperature with PCBN cutter is done and the calculation formula is achieved. A series of experiments about cutting temperature are made for different hardness tempering bearing steel at the same time. The rule that cutting temperature increases with increasing of the cutting speed, feed, back engagement of the cutting edge is gained. It is known that the cutting temperature is highest under the condition that back engagement of the cutting edge a p≥2.5 mm and the machined material hardness equals to 50HRC.

关键词： PCBN cutter Cutting temperature Bearing steel

REGIME MORPHOLOGY OF EQUILIBRIUM ALLUVIAL CHANNELS

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International Journal of Sediment Research 1999年第2期14卷 187-194页

作者： Panayiotis DIPLAS1 (dept.of Civil engineering Virginia Polytechnic Institute and State University, Blacksburg VA,24061, USA)

The concept of turbulent diffusion of downstream momentum in the lateral direction is employed here to develop a model for obtaining the shear stress applied by the flow upon the boundary of channels. The resulting equation, together with the equation desrcibing the balances of forces applied on a sediment particle lying on the channel boundary, are solved numerically to calculate the dimensions of equilibrium alluvial channels. More specifically, threshold channels, and channels with static banks and mobile beds are considered here. Such channels are widely used for irrigation, water supply, flood control and other purposes. The center depth and top channel width obtained from the present model compare favorably with the corresponding values measured from natural streams and laboratory flumes that have reached an equilibrium state.

关键词： Equilibrium alluvial channel Regime morphology shear stress Numerical model

System Dynamics Model of Urban Water Resources Use and It’s Application

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Systems Science and Systems engineering 1995年第2期5卷 125-135页

作者： ZHANG Chao(dept.of Hydraulic engineering of Tsinghua Univ.,Beijing 100084,China)

A new urban water resources use and forecasting model consturcted by comprehensive considering the balance between the supply and demand of the water resources system to an industry city and the feedback relationship of the water resources control policy,and by applying DYNAMO language is presented in this *** can give more rational data of urban water resources simulation and planning than that given by the growth rate trend forecasting method.

关键词： urban water resources System Dynamics forecasting model

INTERNAL FRICTION OF GRAIN BOUNDARIES IN Fe-P AND Fe-P-La ALLOYS CONTAINING TRACE Cu

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Acta Metallurgica Sinica(English Letters) 1990年第4期3卷 243-248页

作者： JI Jingwen WEI Quanjin GENG Dianqi WU Yuqin Northeast University of Technology,Shenyang,China Professor,dept.of physics,Northeast University of Technology,Shenyang 110006,China

The grain boundary internal friction(GBIF)in Fe-P and Fe-P-La alloys containing trace Cu has been *** is found that an addition of 0.584—0.722 wt-% La obviously reduces the IF,shifts grain boundary peaks towards higher temperatures,and produces a small addi- tional peak at even higher *** mechanism of GBIF is explained as the movement of defects of atomic size,namely point defects,at gram boundaries and/or their clusters un- der stress.

关键词： internal friction grain boundary Fe-P alloy La Cu

Absorption in Dichromated Gelation

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Chinese Journal of Lasers 1994年第1期B3卷 43-48页

作者： ZHAO Feng ZHANG Yun JIANG Lingzhen LI Chengjiang GENGWanzhen HONG Jing.(dept.of Applied physics.Harbin Institute of Technology,Harbin 150006,China) Harbin Inst of Technology Harbin China

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关键词： Hologram Dichromated Gelation Absorption Modulation