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Damage on HfO_2/SiO_2 high-reflecting coatings under single and multiple Nd:YAG laser pulse irradiation

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Chinese Optics Letters 2005年第3期3卷 179-180页

作者：高卫东王涛赵元安邵建达 Shanghai Institute of Optics and Fine Mechanics

The single- and multi-shot damage behaviors of HfO2/SiO2 high-reflecting (HR) coatings under Nd:YAG laser exposure were investigated. Fundamental aspects of multi-shot laser damage, such as the instability due to pulse-to-pulse accumulation of absorption defect and structural defect effect, and the mechanism of laser induced defect generation, are considered. It was found in multi-shot damage, the main factors influencing laser-induced damage threshold (LIDT) are accumulation of irreversible changes of structural defects and thermal stress that induced by thermal density fluctuations.

关键词： Defects Irradiation Laser damage Laser pulses Light absorption Neodymium lasers Thermal stress

EXPERIMENTAL STUDY ON THE LOAD DECAY AND ITS EFFECT ON LEAK RATE OFO-RING

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Chinese Journal of Mechanical Engineering 2003年第1期16卷 46-49页

作者： WangGuangzhen WangZhishan 等 DepartmentofPrecisionInstruments TsinghuaUniversityBeijing100084China SchoolofMechanicalEngineeringandAutomation BeijingUniversityofAeronauticsandAstronauticsBeijing100083China

Experimental studies on load decay and leak rate of O-rings made of two kindsof silicone rubber are conducted. The results show that the characteristic of load decay isrelative to the material and temperature of O-rings; the rate of load decay increases with the riseof temperature; the effects of load decay on leak rate of O-rings are negligible at roomtemperature, but they are notable at high temperature, and they are related to the material ofO-rings. On the basis of study on the theory of load decay and analysis to the results ofexperiments, a theoretical model is developed to describe the load decay characteristic of O-rings,and it matches the experimental data very well. By the study of time-temperature equivalence of loaddecay, the interconvertting equation of test data of load decay at different temperatures isobtained.

关键词： Silicone rubber Loading analysis Maxwell model O-ring

New Approach to the Power Selection for Asynchronous Motor

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Journal of Donghua University(English Edition) 2001年第2期18卷 133-139页

作者：高建华胡洪国杨汝清 Res. Inst. of Robotics Shanghai Jiaotong Univ. Shanghai 200030 China

The heating calculation of three-phase squirrel- cage asynchronous motor on the condition of starting for a prescribed rotary angle is firstly studied with time dissection method and its corresponding algorithm is provided. Then based upon the algorithm, a new method for motor power selection is established. Motor initial power determined by load power ischecked and modified in terms of time crit erion, heating criterion,and starting torque *** appropriate motor power which meets three criterions is obtained at last, in the meantime, working displacement matrix andfrequency matrix used for control are acquired. Lifting motor of MDJ1800 low-level high- speed palletizer is taken as a reaI case in the paper.

关键词： time dissection, heating calculation, frequent starting,power selection, three-phase squirrel-cage asynchronous motor

Iterative blind deconvolution of adaptive optics images

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Chinese Optics Letters 2006年第4期4卷 187-188页

作者：梁莹饶长辉李梅耿则勋 Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209 Graduate School of Chinese Academy of SciencesBeijing 100039 Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209 People's Liberation Army Information Engineering University Zhengzhou 450052

Adaptive optics （AO） technique has been extensively used for large ground-based optical telescopes to overcome the effect of atmospheric turbulence. But the correction is often partial. An iterative blind deconvolution （IBD） algorithm based on maximum-likelihood （ML） method is proposed to restore the details of the object image corrected by AO. IBD algorithm and the procedure are briefly introduced and the experiment results are presented. The results show that IBD algorithm is efficient for the restoration of some useful high-frequency of the image.

关键词： Adaptive optics Atmospheric turbulence Image processing Maximum likelihood estimation Object recognition

Development of permanent magnetic refrigerator at room temperature

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Rare Metals 2006年第z1期25卷 641-644页

作者： HUANG Jiaohong LIU Jinrong JIN Peiyu YAN Hongwei QIU Jufeng XU Laizi ZHANG Jiuxing Key Lab of Advanced Functional Materials the Ministry of Education Beijing University of Technology Beijing 100022 China Baotou Research Institute of Rare Earths Baotou 014030 China Baotou Research Institute of Rare Earths Baotou 014030 China Baotou Research Institute of Rare Earths Baotou 014030 China Baotou Research Institute of Rare Earths Baotou 014030 China Baotou Research Institute of Rare Earths Baotou 014030 China Baotou Research Institute of Rare Earths Baotou 014030 China Key Lab of Advanced Functional Materials the Ministry of Education Beijing University of Technology Beijing 100022 China

A reciprocating magnetic refrigerator was developed based on the active magnetic regeneration technology. Rare earth metal Gd and intermetallic compound LaFe11.2Co0.7Si1.1 were used as the magnetic operating materials in the machine. The particles of the magnetic operating materials, with diameter of 0.5-2 mm and total mass of 950 g, were mounted in the cooling bed. A magnetic field was assembled using NdFeB rare earth permanent magnets. It had the magnetic field space of Φ 34×200 and the magnetic induction of 1.5 T. The water at pH=10 is used as a heat transfer fluid. When the ambient temperature is 296 K, a temperature span of 18 K was achieved after operation of 45 min at a frequency of 0.178 Hz. The temperature span and the output power increase significantly with the increasing velocity of heat transfer.

关键词： room temperature magnetic refrigerator NdFeB permanent magnet rare earth metal

Stitching algorithm for annular subaperture interferometry

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Chinese Optics Letters 2006年第4期4卷 211-214页

作者：侯溪伍凡杨力吴时彬陈强 Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209 Graduate School of the Chinese Academy of SciencesBeijing 100039 Institute of Optics and Electronics Chinese Academy of Sciences Chengdu 610209

Annular subaperture interferometry （ASI） has been developed for low cost and flexible test of rotationally symmetric aspheric surfaces, in which accurately combining the subaperture measurement data corrupted by misalignments and noise into a complete surface figure is the key problem. By introducing the Zernike annular polynomials which are orthogonal over annulus, a method that eliminates the coupling problem in the earlier algorithm based on Zernike circle polynomials is proposed. Vector-matrix notation is used to simplify the description and calculations. The performance of this reduction method is evaluated by numerical simulation. The results prove this method with high precision and good anti-noise capability.

关键词： Alignment Computer simulation Image reconstruction Interference suppression Mathematical transformations Matrix algebra Optical systems

Electrochemical behavior of Ce(III) in LiF-BaF_2 melts

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Journal of Rare Earths 2012年第2期30卷 151-154页

作者：林如山叶国安何辉唐洪彬欧阳应根 Department of Radiochemistry China Institute of Atomic Energy

The electrochemical behavior of Ce（III） was investigated in the molten LiF-BaF2 （81 mol.%-19 mol.%） on a molybdenum elec-trode in the temperature range of 1098-1188 K using cyclic voltammetry and chronopotentiometry. It was observed that CeF3 could be re-duced into cerium metal in a reversible one-step process exchanging three electrons （Ce（III）＋3e-→Ce（0）） at the operating temperatures on a molybdenum cathode. The electrochemical reduction process was controlled by the diffusion of Ce（III） in the solution. The Ce（III） diffusion coefficients were calculated at different temperatures and the values obeyed the Arrhenius law with an activation energy of 87.5 kJ/mol.

关键词： molten salt fluoride electrochemistry cerium LiF-BaF2 rare earths

Crystallization in Pb-Zr-Ti-Si-O gel glass

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Chinese Science Bulletin 1996年第21期41卷 1835-1838页

作者：赵青春姚奎张良莹姚熹 Electronic Materials Research Laboratory Xi'an Jiaotong University Xi'an 710049 China

Materials in the lead zirconotitanate system possess useful and interesting electroopticaland piezoelectric *** the sol-gel method possesses a number of desirableadvantages compared with conventional methods, it has been developed as an importantand potential process enabling the preparation of oxide glasses which are difficult or impos-sible to make by conventional ***,ZrO2-TiO2 and ZrO2TiO2-SiO2 with ahigh content of ZrO2,and PbO-TiO2 with PbO were prepared by sol-gel process.

关键词： sol-gel process gel glass perovskite.

STUDY ON A PRECISE ON-SPOT CALIBRATION METHOD FOR DISTRIBUTED STEREO REFERENCE POSITION-SETTING

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Chinese Journal of Mechanical Engineering 2002年第4期15卷 324-327页

作者： Wang Zhong Kou Xinyu Chen Mingzhou Ye ShenghuaState Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University,Tianjin 300072, ChinaXiong ChunbaoTianjin University Tianjin University State Key Laboratory of Precision Measuring Technology and Instruments 天津 300072

A high precision method used for on-spot calibration of distributed stereoreference position setting is presented. The high measuring accuracy in stereo reference calibrationis derived from using a high precision water level instrument and an accurate height verniercaliper. It settles the problem of reference calibration effectively and accurately, without usinglarge coordinate measuring machines (CMM). It is more adaptable and precise than traditionalcalibration methods applying theodolites or autocollimators. The error sources of this method areanalyzed in detail and several methods are developed to eliminate the calibration *** swallowtail-like anchor target is developed. Experiments show that the calibrationaccuracy can be limited within 0.06 mm in the range of 3～5 m and 0.03 mm with optimizing anchortarget. This method can be widely used in on-spot calibration.

关键词： position setting reference calibration water level on-spot inspection error analysis