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1.
The design of a simple inexpensive instrument which can be used along with a simple laboratory microscope to measure microhardness of crystals is described. The design is based on the fact that the lengths of arms of indentation dislocation rosette (idr) are related to the hardness. By controlled indentation and subsequent etching of two similar crystals, the microhardness of one can be estimated in terms of that of the other from measurements of the arms ofidr.  相似文献   

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We propose to build at SOLEIL a facility for the accurate measurement of the properties of optical elements and detectors from the extreme ultraviolet (EUV), soft X-ray spectral regions up to the hard X-rays. The beamline will serve as a standard for such measurements and hence we call it a calibration and standards beamline, or alternatively, a metrology beamline. This beamline will also be valuable as a general-purpose beamline to prepare, test and set up a wide range of experiments. A complementary important aspect of this installation is the realization of a primary standard (as in BESSY II) [1 Ulm, G. 2003. Radiometry with synchrotron radiation. Metrologia, 40: S101S106. [Crossref], [Web of Science ®] [Google Scholar]]: in this case, the metrology beamline of SOLEIL could become the national primary standard source in collaboration with the Laboratoire National d'Essais (LNE) partner of this project. In another field, this installation will be used in the design and characterization of several diagnostics for the Megajoule Laser in Bordeaux in collaboration with the CEA DIF, also a partner of this project.  相似文献   

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新型钕铁硼电磁阻尼演示仪   总被引:1,自引:0,他引:1  
王爱军 《大学物理》2000,19(8):36-37
利用稀土永磁材料钕铁硼(Nd-Fe-B)设计制作出一种新型电关演示仪,可演示阻尼振动的三种状态(欠阻尼状态、临界阻尼状态、过阻尼状态),配合投影仪使用,演示效果显著。  相似文献   

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主要介绍了根据动态法测量原理设计的新型杨氏模量自动测量仪,此仪器创新性地采用全自动扫频技术,实现了金属材料杨氏模量的全自动测量,并且增加了虚假共振的判断和品质因素的测量,提高了测量结果的可靠性.  相似文献   

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This paper describes a novel method of measuring sound insulation in frequency bands or dB(A) using pistol shots as the source. The method has the advantages of speed and economy in comparison with classical measurements. Comparisons of the impulsive and classical methods are given for a number of structures and it is shown that the agreement is generally good.  相似文献   

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A new method for angular displacement measurement   总被引:3,自引:0,他引:3  
We describe a new method for angular displacement measurements that is based on a Fabry-Perot interferometer. A measurement accuracy of 10-8 rad is obtained by use of the sinusoidal phase modulating interferometry. Another Fabry-Perot interferometer is used to obtain the key initial angle of incidence.  相似文献   

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A novel instrument based on Self-mixing interferometry is proposed to simultaneously measure absolute distance and velocity. The measurement method is designed for working directly on each kind of surface, in industrial environment, overcoming also problems due to speckle pattern effect. The laser pump current is modulated at quite high frequency (40 kHz) and the estimation of the induced fringes frequency allows an almost instantaneous measurement (measurement time equal to 25 µs). A real time digital elaboration processes the measurement data and discards unreliable measurements. The simultaneous measurement reaches a relative standard deviation of about 4·10−4 in absolute distance, and 5·10−3 in velocity measurement. Three different laser sources are tested and compared. The instrument shows good performances also in harsh environment, for example measuring the movement of an opaque iron tube rotating under a running water flow.  相似文献   

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声速测量装置的改进   总被引:1,自引:3,他引:1  
潘学军 《物理实验》2006,26(5):18-21
采用低频数字信号源推动小型扬声器做声源,用静电式驻极体传感器做拾音器,对传统的声速测量装置进行了改进.改进后的装置不仅能测量不同频率的声速,而且又降低了成本.本文详细介绍了电路的组成及测量结果.  相似文献   

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畸变是评价光学成像系统像质的一个重要参数。在建立系统的畸变数学模型的基础上,利用计算机辅助方法,通过精确定位被测CCD摄录一体机光学中心的位置,由被测系统采集高精度目标靶的图像,并对数字图像进行处理,实现了对CCD摄录一体机畸变的测量。通过软件对系统进行畸变校正,可使被测系统的畸变测量的相对不确定度达到了0.11%。畸变校正技术可用于电视制导、航空测绘、飞船交汇对接等方面。  相似文献   

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用发光二极管实现的双通道、双色红外CO_2分析仪   总被引:1,自引:1,他引:0  
介绍了一种采用发光二极管InAsSbP作光源、以PbSe探测器作光电转换器件实现的红外CO2浓度分析仪。分析仪由探测器系统、信号放大与处理系统及显示输出系统三部分组成。探测器系统主要包括发光二极管InAsS bP、红外窗口、气路、取样泵、球面反射镜、带通滤光片及PbSe探测器等;信号放大与处理系统主要包括电压跟随放大电路、采样保持电路、多路模拟开关、模 数转换电路及8031单片机等;显示输出系统主要包括显示器、打印机及声报警器等。叙述了分析仪的工作原理、基本结构及主要技术指标,讨论了其中的技术难点及其相应的解决方法,并给出了其所能达到的技术指标。  相似文献   

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天空亮度分布在大气光学领域有着重要的应用。利用Modtran计算了在各种大气、地表条件下的天空亮度分布,分析了大气模式、能见度、云对天空亮度分布的影响,给出了天空亮度的大致动态范围,为天空亮度测量仪器的研制,特别是探测器的选择提供了科学依据。  相似文献   

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引入了一种根据正午12点时杆的影长来确定所在地纬度的方法.根据球面天文学知识,得出了通过杆在当地正午的影长、原长及测量日期来计算纬度的公式,并对该结果进行了实验验证.测得徐州市纬度为34.15°,与公布的标准值基本一致.还将该方法进行了推广,使测量时间不只局限于正午,并对测量的误差进行了分析和修正.  相似文献   

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磁滞回线测量仪的设计   总被引:1,自引:0,他引:1  
为了测量多种形态磁性材料的磁滞回线,设计了磁滞回线测量仪.该仪器的磁感应强度探测器采用双线圈反相连接的方式,磁性材料可以放于任一探测线圈中,方便更换.测试表明,该套实验仪器具有良好的性能,输出图形清晰、分辨率高.  相似文献   

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多普勒效应测试仪的改进   总被引:3,自引:0,他引:3  
邱宁 《物理实验》2002,22(9):18-21
为了解决电磁波多普勒效应在实验室演示的困难,采用单片机和一系列大规模集成电路设计了一种演示电磁波多普勒效应的测试仪器,分析了电磁波的多普勒效应原理,给出了该仪器的组成结构,介绍了该仪器铁特点。  相似文献   

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光指针式微小位移测量仪巧用光路将微小的位移量放大,从光指针终端的标度盘上可以直接读取实际的位移数值.  相似文献   

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