2m比长仪动态校准位移传感器的研究

介绍了2m比长仪的改造及其功能的拓展,用其校准大量程位移传感器的方法.以校准激光三角法位移传感器为例,采用动态校准方法实现可外触发位移传感器的校准.对德国米依公司optoNCDT1700激光位移传感器进行了校准实验,在比长仪滑板运动速度为1mm/s情况下进行了动态测量,实验验证了传感器的全量程线性度小于0.08%FSO.     

拉线位移传感器校准方式研究

根据拉线位移传感器的基本原理和JJF 1305-2011《线位移传感器校准规范》,本文研制了基于双频激光干涉仪的专用校准装置,提出了相应的校准方法,实现了此类传感器的量值溯源,并对其示值误差进行了相应的测量不确定度评定.研究结果表明,该校准装置操作简单、精度高、稳定性好,能满足常见拉线位移传感器量值溯源的需求.     

纳米力学测量系统的载荷与位移溯源校准方法研究

对纳米力学测量系统在准静态压入模式下的载荷因子、位移因子的量值溯源校准方法进行了研究。通过一组标准砝码产生标准载荷,拟合标准砝码质量和传感器输出电压得到载荷因子;利用激光干涉仪测量压针位移,拟合干涉仪位移值和传感器输出电压得到位移因子。采用标准样品对校准结果进行了试验验证,校准后的纳米力学测量系统在国际比对测量中取得了良好结果。     

线位移传感器校准的一种新装置

在飞机系统综合试验中,线位移传感器的静态特性对保证试验数据的准确性、可靠性起着至关重要的作用.为此,我们研制了一种线位移传感器静态校准装置.本文主要叙述线位移传感器静态校准装置软、硬件组成及工作原理,并对其进行了测量不确定度分析.实践证明,该装置设计科学、合理,能够完全满足校准需求.     

激光位移传感器校准方法研究

文章分析了常见的激光位移传感器校准方式,基于激光位移传感器的工作原理和JJF 1305-2011,设计了一套校准激光位移传感器的标准装置并研究了相应的校准方法,最后在实验室环境下开展了相关的校准实验及其示值误差的测量不确定度评定.     

线位移传感器校准及不确定度分析

针对线位移传感器种类较多的特点,分析了当前可参照执行的国家技术标准和技术规范.提出选用激光干涉仪校准线位移传感器的方法,给出校准系统装置和校准方法的测量不确定度.讨论了位移传感器的静态指标的计算方法以及校准过程中常见技术问题.     

一种便携式激光位移传感器校准装置

企业生产在线检测中使用许多激光位移传感器,它能够精确非接触测量被测物体的位置、位移等变化。为了能够实现激光位移传感器的现场校准,研制了一种便携式激光位移传感器校准装置,可以在现场检测,无需将其整体拆卸送检,并结合激光位移传感器尺寸特性,设计研制出符合其测量要求的装置微动台,可以任意方向调节位置。实验证明,本装置满足激光位移传感器的校准需求,解决了无法携带校准设备的难题,可以大力推广,具有较好的应用前景。     

气体脉冲压力的激光干涉法测量

对气体动态压力的非接触测量和溯源方法进行了研究。研制了基于激光干涉法测量气体脉冲压力的实验装置,通过光程与压力关系计算分析出气体脉冲压力的幅值和脉宽。建立了动态压力测量模型,并对测量不确定度进行了分析。开展了气体脉冲压力激光干涉测量实验,使用动态压力传感器和激光器进行同步测量,激光干涉法测量结果偏差较小,验证了装置测量的准确性。结果表明：本装置产生的脉冲压力信号稳定可靠,光学测量信号准确度高,具有实时性、非接触、可溯源等优点,可实现气体脉冲压力的测量,装置测量结果的相对标准偏差小于0.8%,测量结果的不确定度小于2%(k=2)。     

产生任意波形信号的系统及其在标准微位移发生装置中的应用研究

描述了能够产生任意波形信号的信号发生系统的构成、工作原理和关键技术,并将能产生任意波形信号的标准信号发生系统应用于标准微位移发生装置中,控制标准微位移发生装置产生任意形状的标准微位移运动轨迹及模拟标准器形状轮廓轨迹,以实现对微米测量范围的位移传感器的动态校准.通过实验验证了该系统及标准微位移发生装置的准确性及实用性.     

基于Hammerstein模型的MAF传感器的动态补偿研究

用Hammerstein模型表示具有动态非线性特性的汽车空气质量流量(MAF)传感器,所设计的动态非线性补偿器包括动态线性补偿器和静态非线性校正器.对动态标定实验装置中的阀门进行建模,阀门的阶跃响应作为传感器的激励信号.应用系统辨识法设计动态线性补偿器,应用反函数多项式拟合法设计静态非线性校正器.仿真结果表明,动态线性补偿器起到改善传感器动态性能指标的作用,静态非线性校正器可以保证校正后无失真的复现传感器的输入信号.同时,所设计的动态非线性补偿器具有良好的适应性,在传感器的不同幅值输入时,都起到了动态性能指标改善、稳态幅值无失真复现的作用.     

热交换器的分类及优缺点分析

热交换器是将不同温度介质之间的热量通过热传导的形式,由高温介质传递给低温介质,使介质达到生产所需温度的工艺设备,也可作为一种节能设备使用.通过对不同热交换器的结构分析,总结不同热交换器的优缺点、适用环境,为生产工艺设计人员及设备制造单位在选择可降低能耗、提高效率的设备上提供参考.     

聚苯胺及其复合物的制备和结构及形貌分析

通过化学氧化法分别制备盐酸,盐酸和十二烷基苯磺酸,碳纳米管(MWNTs-COOH)掺杂的聚苯胺,利用红外光谱,紫外光谱,扫描电子显微镜和透射电子显微镜对所制备聚苯胺的结构和形貌进行分析。分析不同掺杂物对聚苯胺的结构和形貌的影响;同时研究了超声波作用对聚苯胺形貌以及聚苯胺包裹MWNTs-COOH情况的影响。     

Thermodynamic similarity and prediction of the properties and characteristics of substances and processes

Principles of the theory of thermodynamic similarity are considered in application to all aggregate states of a substance, including phase transitions, and to the change in dissipative structures in open systems.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 5, pp. 709–716, November, 1987.     

Modelling and computation of curing and damage of thermosets

The curing of thermosets is a complex process involving the transition from a fluid into a (visco-) elastic solid. This phase transition comes along with an increase in stiffness and a volume shrinkage of the polymer. The latter may lead to severe residual strains and stresses, which in turn can cause damage in the final, usually quasi-brittle material. In this contribution a constitutive model is developed which takes into account the curing of a thermosetting material together with the process-induced damage as resulting from curing shrinkage. The curing of the material is governed by a phenomenological hypoelastic constitutive equation which includes temporal evolutions for stiffness and volume shrinkage. Thermal and viscous effects are neglected in the present study. An isotropic gradient-enhanced damage model is adapted to describe the damage evolution. The curing-damage model is implemented into a finite element code and numerical examples for thermosetting materials demonstrate that the proposed model is capable to predict cure-induced damage in thermosets.     

Mechanisms of Corosion and Oxidation of Metals and Alloys

Selected topics in field of the study of the mechanisms of corrosion and of oxidation of metals or alloys are presented. The first part reports a new model for the mechanism of the breakaway oxidation of ferritic stainless steels in water vapour. The second part is devoted to the physico‐chemical aspects of oxidation and presents experimental methods useful in the kinetic modelling applied to two alloys, the zircalloy‐4 and an AlMg5 % in the liquid state. In the third part the physical and numerical modelling of the stress corrosion cracking behaviour in face‐centered cubic (fcc) alloys is detailed, which enables the study of the influence of macroscopic parameters (such as the temperature or hydrogen activity) on the fracture process.     

碳化硼陶瓷增韧补强和致密化研究现状及其展望

碳化硼陶瓷具有极高的硬度,然而其低韧性、低抗弯强度、难以致密化限制了它的广泛应用.已有一些研究集中于碳化硼陶瓷增韧补强和致密化,对这一方面国内外研究进展进行了归纳与评述,阐明各种增韧补强和致密化方法的优缺点,提出碳化硼陶瓷增韧补强和致密化研究值得发展的一些方向.     

Measurement and analysis of elastic and anelastic properties of alumina and silicon carbide

Measurements of dynamic Young's modulus, E, and damping as a function of temperature, T, were made for alumina and silicon carbide. The Young's modulus data were compared with some from the literature, and analysed in terms of a theoretical framework relating the Debye temperature, θD, with the elastic constants. For both materials this analysis yielded a ratio T₀/θ_D which was near 0.4, where T₀ is an empirical fitting constant for the plot of (E(0)−E)/T versus 1/T (E(0) is the value of E at 0 K). The analysis of the damping data in terms of an Arrhenius type dependence led to effective activation energies near kT, where k is Boltzmann's constant. This revised version was published online in November 2006 with corrections to the Cover Date.     

Preparation and characterization of phosphate and arsenate apatites of strontium and their solid solutions

Samples of phosphate and arsenate apatites of strontium and six of their solid solutions, spread over the entire compositional range, were prepared by a wet method. They were characterized by chemical, X-ray, electron microscopic and infrared analyses. The validity of Vegard's law established the homogeneity of the solid solutions.     

检定和校准证书的异同与应用

本文介绍了检定和校准以及证书的两点相同、五点不同之处,说明了对检定证书和校准证书的正确应用。