金属丝杨氏模量的光纤测试方法

采用光纤位移传感器,测量了加载情况下金属丝的微小伸长量,给出了一种杨氏模量的测量方法。理论上, 光纤位移传感器特性,与实验结果进行了对比。通过实验,标定了光纤位多传感器,并测量了不同加载情况下金属丝微小伸长量。采用逐差法处理了实验结果。     

反射式光纤位移传感器应用设计实验

基于光的反射原理并结合光纤传感器的特点,设计了反射式光纤位移传感器应用设计性实验.利用反射式光纤传感器测量微小位移的原理,通过测量输出电压与位移的关系确定工作点,测得表面柤糙程度不同的真假钞的输出信号,从而实现对纸币的真假识别.     

基于强度补偿式光纤传感器测金属线胀系数

分析了强度补偿式光纤位移传感器的补偿机理.通过测量定标,应用最小二乘法确定了该传感器的特性曲线和拟合方程.使用强度补偿式光纤传感器测量了黄铜和铝杆的线胀系数.实验结果表明:强度补偿式光纤位移传感器采用比值运算法给出测量结果,其灵敏度高,稳定性好,用其测量微小位移,可消除一些传统测量方法中待测参量较多而引入过多测量误差的问题,实现非接触测量,且克服反射式非补偿位移传感器因光源光强波动、光纤传输介质损耗及环境光干扰所带来的测量误差.     

纳米级光纤位移传感器

介绍利用高斯光束干涉测微小位移的方法,利用该方法设计了纳米级光纤位移传感器,测试了该传感器的位移响应与频率响应.     

一种新型双参量光纤布喇格光栅传感器的研制

介绍了一种新型的具有双参量测量功能的光纤布喇格光栅传感器.该传感器采用了特殊的结构,安装了两个不同中心波长的光纤布喇格光栅,可以实现两曲面之间狭小间隙的微小位移和温度的同时测量.实验表明,该传感器结构紧凑、体积小,具有良好的重复性和稳定性,位移测量误差不超过±10 μm,温度测量误差不超过±2℃.     

适用于硅微谐振器件测量的光纤位移传感器研究

对一种适用于硅微机械谐振器件测量的光纤位移传感器进行了研究,该光纤位移传感器探头采用了单根光纤探测形式和光纤“X”耦合器结构,在微弱光电传感信号处理上采用了“锁相放大器”提取方案,可以实现对静态位移和振动位移两种场合进行测量.对该传感器的实测结果表明:该传感器测量范围为0～100 μm,测量灵敏度3.95 mV/μm,精度等级优于1%,重复性优于0.5%.为作为应用实例,运用该传感系统对一种微悬臂梁硅微谐振器件进行了测量,成功提取了硅微谐振器件的微弱谐振信号,证实了该传感器可以实现对硅微谐振器件的非接触和无损测量,并具有非接触、易调试、高灵敏度等优点.     

光纤传感器位移和转速测量研究

介绍光纤传感器的测量原理,并对位移和转速测量进行研究,利用matlab软件对位移测量结果进行曲线拟合,且将光纤传感器和电涡流传感器的转速测量结果进行比较,最后得出利用光纤传感器进行测量具有电路结构简单、精度高、光路弯曲等优点。     

等芯径等间距三光纤补偿式位移传感器的实验研究

介绍了补偿式光纤位移传感器的结构和原理,实验测量了等芯径等间距光纤位移传感器的输出特性和位移的关系. 结果表明:2根接收光纤各自的线性范围小,补偿后的光纤位移传感器不仅能改善测量的线性度,而且能在一定程度上放大传感器的线性测量范围. 补偿式光纤位移传感器采用等芯径等距离方式可以有效地消除光源输出强度波动、表面反射率不同和光纤传输损耗对输出特性的影响.     

具有温度补偿的光纤位移传感器

位移测量是结构健康检测的重要参量之一.本文提出了一种双悬臂梁粘贴光纤光栅的位移传感器,它将位移变化转换成两只光纤光栅的波长移动,实现对位移量的绝对测量.通过引入对称补偿光纤光栅的方法解决了温度与位移交叉敏感的问题.推导了位移传感器的工作原理,完成了相关实验,并分析了传感器所产生误差的来源.实验结果表明,在量程为20 m...     

微小位移光纤传感器谐波分析解调法研究

本文从理论上阐述了微小位移光纤传感器的一种分频比较法解调方案,并利用全光纤干涉光路进行了实验,结果表明采用这种解调方法可提高光纤传感器的测试精度、稳定性和动态范围。     

Theoretical and experimental studies on coupler based fiber optic displacement sensor with concave mirror

A new fiber optic displacement sensor (FODS) is proposed and demonstrated using a multimode fiber coupler as a sensor probe and a concave mirror as a reflective target. A mathematical model is also developed to investigate the performance of proposed FODS at various coupling ratio, fiber diameter, and surrounding media. Three slopes are obtained for the displacement response where the third slope starts at a displacement position of twice the focal length. The numerical results show that higher performance is attained at lower coupler ratio of 50:50 or smaller core diameter. The results also show that the proposed FODS has a potential application in liquid and gas chemical sensors. The experimental performances are also investigated for the proposed sensor where it is observed that the second peak of the displacement curve is located at exactly two times of the focal length or 20 mm.     

Investigation of charged-hadron production in proton–nucleus interactions at the energy of 50 GeV

Cross sections for the production of high-transverse-momentum charged hadrons in proton–nucleus interactions at the incident-proton energy of 50 GeV were measured with the aid of the FODS double-arm spectrometer. Single hadrons (charged pions and protons) emitted at a c.m. angle of about 90° and high-effective-mass pairs of hadrons flying apart at a c.m. angle of 180° were detected simultaneously. Results on the production of single hadrons are presented.     

Simulation of elastic displacement of surface during laser short pulse heating of gold

The laser short pulse heating initiates nonequilibrium heating of the substrate material, which in turn results in the thermal stresses developing in the region below the surface. The surface temperature can be measured possibly through the monitoring of the resulting surface displacement. This requires in detail investigation into the surface displacement and surface temperature rises across the heated spot during the laser short pulse heating process. In the present study, the laser short pulse heating of gold surface is considered and the temperature rise at the surface and elastic displacement of the surface are investigated. The spatial and temporal distributions of surface displacement and surface temperature are predicted and the elastic response of the substrate material due to temperature rise is explored. It is found that the temporal and spatial distributions of the surface displacement do not follow the temperature rise at the surface. Consequently, care should be taken when measuring the temperature rise at the surface by means of monitoring the surface displacement during a laser short pulse heating process.     

基于啁啾光纤光栅的温度自补偿位移传感器

基于双三角结构的悬臂梁,提出了一种使用啁啾光纤光栅测定位移的方法.悬臂梁受到应力时引起刚性粘接在悬臂梁上的啁啾光栅反射谱带宽压缩,通过测量反射谱带宽进行位移的测量.该结构克服了位移测量时温度的交叉敏感问题,温度变化引起反射谱整体移动但不会改变带宽.测试结果表明该传感器具有较高精度、良好的线性和可重复性等优点.     

Spin physics in high-energy hardon interaction

Data on single-spin asymmetry (A_N) in high-energy hadron-hadron collisions are discussed. The data are classified according to the beamand target types. The single-spin asymmetry A_N is considered as a function of kinematical variables and the sort of participant particles. Data from the PROZA and FODS facilities operating in beams of the IHEP accelerator are presented. The origin of a large single-spin asymmetry is briefly considered.     

合肥光源BPM真空室位移的测量与分析

合肥光源电子储存环的束流水平轨道存在缓慢漂移现象, 本文针对这一现象进行了束流位置检测器(BPM)真空室形变、位移和温度等参数的测量. 通过这些测量, 分析了BPM真空室的形变、位移、温度以及束流轨道漂移与束流流强的关系, 对束流水平轨道的漂移现象做出合理的解释, 即导致轨道水平漂移的主要原因是同步光热效应导致BPM真空室水平移动, 提出了采用补偿方法对BPM的轨道测量值进行实时修正, 从而提高了慢速轨道反馈系统有效性.     

The local displacement field around Co and Nb solutes in ω-phase forming bcc-Zr at high temperatures

In order to determine the displacement field around Co and Nb solutes in high temperature bcc-Zr the diffuse scattering intensity was measured in Zr_0.985Co_0.015 and Zr_0.92Nb_0.08. Strong diffuse intensities were found in the (110) and in the (001) reciprocal planes. The comparison of these results with model calculations shows that Co as well as Nb atoms cause radial symmetric displacement fields in the high temperature bcc phase of Zr. -phase like displacements around these defects, on the other hand, can explain the measured diffuse intensities less well. It is concluded, that the resulting displacement field is a superposition of all displacements for which low energy phonons exist. These low energy phonons are related to the martensitic transitions of the bcc structure to the hcp and -structure.     

基于光纤Bragg光栅位移测量的研究

介绍了一种基于布喇格光纤光栅技术的位移测量方法。利用宽带光源经不同的布喇格光栅得到一种由温度稳定器控制波长稳定性的合成光源。由于系统设计的合成光源波长比常规光源的波长长，所以允许的光程差测量范崮提高了几百倍，从而使得布喇格光纤光栅的波长准确性提高了干涉仪位移测量的准确性。此外，利用光外差法马赫一曾德尔干涉仪进行了位移测量实验，得到了很好的效果。     

Experimental investigation of the temperature field in the gas-liquid two-layer system

Results of an experimental investigation of the temperature field across the liquid-gas two-layer system are presented. The liquid layer is locally heated from the bottom substrate, and the intensive liquid evaporation is observed. A technique for measuring the temperature profile across the liquid and gas layers (including their interface) is developed. To do these measurements, the microthermocouple is moved across the layers with the help of precision micropositioner with a step of 1 μm. The temperature jump at the liquid-gas interface is measured, and its value increases with the temperature increase. Detailed information on the temperature field near the interface is obtained by using the precise thermocouple displacement with a small step.     

Mean square displacement of xenon atoms in an epitaxial monolayer on (0001) graphite

The thermal variation of the mean square displacement of xenon atoms adsorbed in epitaxy on (0001) graphite is measured by low energy electron diffraction in the 48–73°K temperature range. Lattice dynamics calculation is in good agreement with experimental results.