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Effective Reflection Area of a Cube Corner Retroreflector

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Chinese Journal of Lasers 2000年第5期9卷 46-50页

作者： CAI Yanmin FANG Zujie CHEN Gang CHEN Gaoting (Shanghai Institute of Optics and Fine Mechanics, The Chinese Academy of Sciences, Shanghai 201800, China) received Jan. 26, 2000 revised manuscript received apr. 25, 2000 中科院上海光学精密机械所上海

The effective reflection area of a cube corner retroreflector is defined. It is testified for a cube corner retroreflector (CCR) that the ray reflected from a CCR is not parallel with the ray incident on the CCR undersurface. The effective reflection area of CCR is calculated when the ray incident on the CCR undersurface vertically, and the effective reflection area of a CCR is two thirds of the CCR undersurface.

关键词： cube corner retroreflector reflect effective reflection area

Glass ceramic of high hardness and fracture toughness developed from iron-rich wastes

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Acta Metallurgica Sinica(English Letters) 2009年第3期22卷 181-190页

作者： Weixin HAN Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China manuscript received 27 October 2008 in revised form 17 November 2008 [a]Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A study has been carried out on the feasibility of using high iron content wastes, generated during steel making, as a raw material for the production of glass ceramic. The iron-rich wastes were mixed and melted in different proportions with soda-lime glass cullet and sand. The devitrification of the parent glasses produced from the different mixtures was investigated using differential thermal analysis, X-ray diffraction, and scanning electron microscopy. The mechanical properties of the glass-ceramic were assessed by hardness and indentation fracture toughness measurement. A glass ceramic with mixture of 60 wt pct iron-rich wastes, 25 wt pct sand, and 15 wt pct glass cullet exhibited the best combination of properties, namely, hardness 7.9 CPa and fracture toughness 3.75 MPa·m^1/2, for the sake of containing magnetite in marked dendritic morphology. These new hard glass ceramics are candidate materials for wear resistant tiles and paving for heavy industrial floors.

关键词： Iron-rich wastes Glass ceramics Vitrification Hardness

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Research of Methods for Controlling Laser Focal Profile by Adaptive Optical Technology

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Chinese Journal of Lasers 1998年第1期 64-73页

作者： ZENG Zhige LING Ning JIANG Wenhan(Institute of Optics & Electronics, Chinese Academy of Sciences, Chengdu 610209, China)received Jan. 27 1997 revised manuscript received apr. 27 1997

ＲｅｓｅａｒｃｈｏｆＭｅｔｈｏｄｓｆｏｒＣｏｎｔｒｏｌｉｎｇＬａｓｅｒＦｏｃａｌＰｒｏｆｉｌｅｂｙＡｄａｐｔｉｖｅＯｐｔｉｃａｌＴｅｃｈｎｏｌｏｇｙＺＥＮＧＺｈｉｇｅＬＩＮＧＮｉｎｇＪＩＡＮＧＷｅｎｈａｎ（Ｉｎｓｔ... 详细信息

ＲｅｓｅａｒｃｈｏｆＭｅｔｈｏｄｓｆｏｒＣｏｎｔｒｏｌｉｎｇＬａｓｅｒＦｏｃａｌＰｒｏｆｉｌｅｂｙＡｄａｐｔｉｖｅＯｐｔｉｃａｌＴｅｃｈｎｏｌｏｇｙＺＥＮＧＺｈｉｇｅＬＩＮＧＮｉｎｇＪＩＡＮＧＷｅｎｈａｎ（ＩｎｓｔｉｔｕｔｅｏｆＯｐｔｉｃｓ＆Ｅｌｅ...

关键词： focal profile adaptive optics computer simulation

Study　On　Laser　Fiber　Diameter　Measurement　Instrument

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Chinese Journal of Lasers 1995年第6期B4卷 543-548页

作者： ZHOU Ge LIU Zeyi LI Heqiao MAO Yi ZHANG Yimo(Institute of Optoelectronic & Precision Engineering ☆Dept. ofMathematics,Tianjin, Tiajin 300072, China)received 5 Dec. 1994 revised manuscript received 17 apr. 1995 Tianjin Univ Tianjin China

ＳｔｕｄｙＯｎＬａｓｅｒＦｉｂｅｒＤｉａｍｅｔｅｒＭｅａｓｕｒｅｍｅｎｔＩｎｓｔｒｕｍｅｎｔ￥ＺＨＯＵＧｅ；ＬＩＵＺｅｙｉ；ＬＩＨｅｑｉａｏ；ＭＡＯＹｉ；ＺＨＡＮＧＹｉｍｏ（ＩｎｓｔｉｔｕｔｅｏｆＯｐｔｏｅｌｅｃｔｒ... 详细信息

ＳｔｕｄｙＯｎＬａｓｅｒＦｉｂｅｒＤｉａｍｅｔｅｒＭｅａｓｕｒｅｍｅｎｔＩｎｓｔｒｕｍｅｎｔ￥ＺＨＯＵＧｅ；ＬＩＵＺｅｙｉ；ＬＩＨｅｑｉａｏ；ＭＡＯＹｉ；ＺＨＡＮＧＹｉｍｏ（ＩｎｓｔｉｔｕｔｅｏｆＯｐｔｏｅｌｅｃｔｒｏｎｉｃ＆ＰｒｅｃｉｓｉｏｎＥｎｇ...

关键词： optical power spectrum fiber diameter distribution

Timing Jitter Induced by White Noise in Mode-locked Solid-state Lasers

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Chinese Journal of Lasers 2000年第5期 28-33页

作者： LU Hong 〔The Femtosecond Technology Research Association (FESTA), 1 1 4 Umezono, Tsukuba Ibaraki 305 8568, Japan〕 received Feb. 15, 2000 revised manuscript received apr. 10, 2000

A new method is proposed to analyze and calculate the jitters in a mode locked solid state laser with chirp. A set of motion equations for amplitude, inverse pulse width, chirp, frequency, pulse central position and phase in a femtosecond mode locked solid state laser are derived, and then the jitter induced by white noise is obtained. In a Ti sapphire mode locked laser, the jitter is theoretically estimated, and the result is well consistent with the experimental value.

关键词： timing jitter white noise mode locked solid\|state lasers

High　Energy　He+　Ion　Implantation　in　Titanium　Doped　Sapphire　Crystal

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Chinese Journal of Lasers 1995年第6期B4卷 563-569页

作者： LIU Jianhua ZHANG Qiang DENG Peizhen GAN Fuxi(Shanghai Institute of Optics and Fine Mechanics , Academia Sinica,Shanghai 201800, China)received 3 apr. 1995 revised manuscript received 7 Jun. 1995(Supported by the fund of national Lab. of information fun Shanghai Inst of Optics and Fine Mechanics Academia Sinica Shanghai China

The 2 MeV energy He＋ ion implantation for constructing planar optical waveguide in tunable laser crystal Ti:Al2O3 was performed. Lattice damage by ion bombardmentwas investigated by means of optical and SEM studies, different damage depths of about 5 μmand 10μm for Al-sublattice and O-sublattice of the Ti:Al2O3 substrate were obtained by electron probe microanalysis (EPMA).

关键词： high energy ion implantation optical waveguide Ti:Al2O3 crystal

Development of Mg-based Hydrogen Storage Alloy

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Journal of Materials Science & Technology 2001年第6期17卷 590-596页

作者： Lian bang WANG, Yijing WANG and Hualang YUAM Institute of New Energy Material Chemistry, Nankai University, Tianjin 300071, China manuscript received June 30, 2000, in revised form September 20, 20001 Nankai Univ Inst New Energy Mat Chem Tianjin 300071 Peoples R China

Mg-based hydrogen storage alloys are considered as a promising candidate for hydrogen system because of its lightweight, high storage capacity, low price and rich mineral resources. In detail, we reviewed the preparation and properties of Mg-Ni-based hydrogen storage alloys. All kinds of attempts have been done to improve the hydriding and dehydriding behaviors. It is found that the partial substitution of foreign elements can decrease the hydrogen absorption temperature, especially the substitution of a more electronegative element, such as AI and Mn. Mechanical alloying (MA) and mechanical grinding (MG) are the most effective methods to improve the hydriding/dehydriding kinetics and electrochemical capacity, and decrease the desorption temperature. but the corrosion resistance is so poor that the 80% of maximum capacity is lost within ten cycles. Microencapsulation is a useful measurement for improving the corrosion resistance and electrocatalytic activity. fn order to improve the properties of the alloys for practical application, the alloys should have a large number of defects, which give activated sites, subsequently, MA, MG and electroless plating should be used to improve the hydriding/dehydriding kinetics and protect the surface of alloys, respectively. The new composite Mg-based alloys give a new way for the hydrogen storage material to practical application. Furthermore we put forward several problems which will be discussed in future.

关键词： Development of Mg-based Hydrogen Storage Alloy Ni

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Discussion forthe Semiinfinite Medium Approximation and the Thermal Diffusion Velocity in Laser Heat Treatment

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Chinese Journal of Lasers 1999年第4期8卷 90-96页

作者： LI Junchang LI Xingyi CHEN Jingbo FAN Zebin CHEN Qinghua (Kunming University of Science and Technology, Kunming, 650093, China) received Dec. 14, 1998 revised manuscript received apr. 12, 1999 昆明理工大学云南昆明 650093 昆明理工大学云南昆明

It is a conventional method to regard laser iradiated object as a semi infinite medium with invariable thermal physical property parameters for approximate analyses of thermal acting of laser heat treatment. So far, 2αt and α/t have been taken as the thermal diffusion distance and the thermal diffusion velocity respectively, at the time t after heat fluctuation in materials with a thermal diffusion coefficient α, and as a result, the feasibility of the approximately estimating method about semi infinite medium is judged. This paper indicates that, due to quantitative investigation of heat energy diffusion, the thermal diffusion distance of 3αt and the thermal diffusion velocity of 1.5α/t can more accurately describe the physical process of heat conduction. Finally, an applied example of approximately estimating the temperature field of laser heat treatment is presented.

关键词： laser heat treatment temperature field estimate thermal diffusion velocity

Influence of Grain Boundary on Fatigue Behavior of Ni-base Bicrystals

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Journal of Materials Science & Technology 2002年第1期18卷 69-72页

作者： Jiansong WAN, Zhufeng YUE, Xiaoliang GENG and Zhixian LUDepartment of Engineering Mechanics, Northwestern Polytechnical University, Xi’an 710072, China [ manuscript received January 16, 2001, in revised form apr.l 27, 2001] Dept. of Eng. Mech. Northwestern Polytech. Univ. Xi'an 710072 China

The influence of the grain boundary on the fatigue behavior was studied by two three-point-bending (TPB) specimens. One TPB specimen was named Bicrystal 1, whose pre-crack was along the grain boundary and the applied load paralleled to pre-crack direction, while the other TPB specimen was named Bicrystal 2, whose the pre-crack was perpendicular to the grain boundary and the applied load paralleled also to the pre-crack. It was found that the rate of the fatigue crack growth of Bicrystal 1 was about a tenfold higher than that of Bicrystal 2. The fatigue behavior of Bicrystal 2 specimens was dependent on the distance between the crack tip and grain boundary. The crack growth rate was highest when the crack tip was at a critical distance to the grain boundary, while the rate was the lowest when the crack tip reached grain boundary. After the crack was over the grain boundary, the crack growth rate increased. The crystallographic finite element method was applied to analyze the stress and strain structure ahead of the crack, in order to reveal the above characteristics of the fatigue behavior. It is the grain boundary-induced redistribution of stresses near the crack tip that induces the difference of fatigue behavior.

关键词： Bicrystals Fatigue behavior Grain boundary Shielding effect

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