一种低维材料热膨胀系数的测试系统

热膨胀系数是表征材料性能的一个重要参数 ,但目前对低维材料 (一维线材和二维带材 )的热膨胀系数尚无标准的测试方法。本文设计了一套测量低维材料热膨胀系数的测试系统 ,该系统结构简单、操作方便、可在液氮温度 (- 196℃ )～室温范围内进行连续测量。对该系统进行适当改进后可将其测量温度范围扩展至高温 ,并可实现测量结果自动记录和处理。     

A Dynamic Seebeck Coefficient Measuring Device For High Resistivity Materials

ABSTRACT

A system for dynamical measurement of Seebeck coefficients materials with resistivities-cm is described, with particular attention given to the instrumentation problem. Results are presented which show the system's performance on NiO and VgO.     

温压条件下非金属刚性材料导热系数测定方法的研究

本文研究了非金属刚性材料导热系数的两种测定方法。在室温常压下，对标准试样用方法一的测试值与国际推荐值之间的最大偏差小于１％。方法一与二作比对测试，其最大偏差小于１％。在温度≤５３０Ｋ及压力≤１０Ｍｐａ下，用方法二测试了岩石热导系数随温，压变化的规律。对测试装置的原理性误差以及二次仪表的测量误差分别进行分析和讨论。温压下，其测量结果的最大误差小于７％。     

A Rotary Thermal Probe for Measuring Groundwater Velocity

Abstract

A rotary thermal groundwater flowmeter was studied theoretically and experimentally, and its electrical model was used for searching a linear transference. The velocity measuring range was extended with respect to previous developments, and flow direction estimated by rotating the sensor head of the probe. This instrument was tested under laboratory conditions with the probe in contact with saturated sand and within standard plastic screens. Simulations suggested that the probe would work properly with high flow velocities arising in some groundwater remediation processes. Flow direction was estimated with a mean squared error of 1.3° and a standard deviation of 0.9°.     

薄膜热导率测量结构的研究

提出了一种用于薄膜热导率测量的微器件.利用微机械加工技术制作出相应的结构,其桥状薄膜的面积为800μm×2000μm,悬梁的面积为30μm×100μm,薄膜电阻经悬梁穿过氮化硅薄膜用于加热和测温.薄膜上的热流和温度分布十分均匀,可减小系统误差.实验中对0.5μm到2μm的一系列氮化硅薄膜进行了测量,得到了薄膜热导率的尺寸效应.     

测量旋转体动态参量的新方法

提出一种测量旋转体动态参量的新方法,并开发了实用的ＲＣＤ测量系统。实际应用证明该系统具有很强的抗干扰能力和稳定的动态性能。     

一种齿轮动态测试新方法

我们成功地研制了一种新型的齿轮动态数据测试系统。在齿轮动态误差实验台上进行了实验，结果表明，该系统不仅具有稳定的测试性能，而且与传统方法相比，抗干扰能力极强，理论计算与实验结果完全符合。     

一种测量齿轮齿距误差的动力学方法

本文介绍了一种用磁电式传感器测量齿轮的齿距误差的动力学方法,文中给出了测量原理和相关测量系统,在瞬时转速试验实验台上的实验结果验证了所述方法的正确性.     

A Vacuum High-Temperature Electric Furnace for Investigating Thermal Properties of Materials

A vacuum electric furnace for investigating thermal properties of materials at temperatures of up to 2500°C was developed and tested. The furnace allows experimental studies of the heat conduction of both liquid and solid materials and measurements of the temperature and heat of phase transitions. It can be used to smelt and cake metals and alloys in vacuum or in an inert-gas medium. The heater is made of a graphite tube with special slots for increasing its resistance. The electric power is supplied from an ОСУ-40 step-down transformer. The temperature in the heated zone is controlled and monitored with an РТЭ-4.1 digital temperature controller connected to a computer. The power consumed by the furnace is no higher than 20 kW, and the volume of the working chamber is 0.3 L. The time for reaching the maximum temperature is at most 30 min.     

一种电机转子动平衡测量系统的设计

在分析转子动平衡基本力学原理基础上,提出一种针对电机转子的动平衡测量系统方案。然后根据信号具有变频率及不平衡量比较小时信噪比恶化的特点,开展了基于LMS的自适应消噪算法的研究,从而为高精度提取不平衡信息提供了可靠的保证。实验结果和实际运行表明,该系统达到了实用、高效和高精度的设计要求。     

新一代光辐射测量仪器

介绍了国内新一代光辐射测量仪器的原理和目前进展情况。     

Absorption Spectral Characteristics of Infrared Radiation in Silicon Dioxide Films for Thermal Radiation Detectors

Optoelectronics, Instrumentation and Data Processing - The absorption spectral characteristics of silicon dioxide films in the IR range (λ = 8–14 µm) were studied to determine the...     

General Radiation Damage Problems for Lubricant and Bearing-type Materials

The actual mechanism of radiation damage to materials by reactor radiation is a matter of prime importance. Radiation damage to covalent compounds such as organic lubricants by reactor radiation is due primarily to secondary ionization caused by fast neutrons, slow or thermal neutrons, and gamma rays, and is not largely due directly to the initial interaction of any of these three types of radiation with the nuclei or atoms of the organic compounds. The amount of energy absorbed by a given material from these various types of radiation can be calculated, and the actual damage incurred is a function of the energy absorbed. Based upon available experimental test data of radiation damage to various organic materials and based upon the equivalent absorbed energy-equivalent damage concept, various generalizations regarding organic lubricating materials can be made.     

材料光谱发射比的激光测量法研究

材料的光谱发射比既是辐射度学中的重要物理量,又是热辐射式测温仪表中没有解决处理好的一个关键性问题。本文简述了近年来国内外在这一领域内的工作情况,提出并讨论了利用激光实时测定材料的光谱发射比,以便更准确地测出待测物体温度的方法。     

标定红外热像仪的一种新型黑体辐射源

提出了一种用于标定红外热像仪的黑体辐射源，黑体腔形状为球形，开孔直径与球腔直径之比为0.13。由恒温液体浴保证黑体腔温度分布均匀，采用水浴和酒精浴时，壁耐最大温差低于0．2℃，油浴时壁面最大温差低于0.3℃。该黑体辐射源升温快，控温稳定性好，工作温度范围可达-20～300℃，有效比辐射率大于0.998。     

智能型热性能参数测量仪

本文介绍电子设备中热性能的３个参数－温度、流速（量）和压力损失（压降）；应用单片机和相关传感器组合而成的测量装置，包括硬件、软件设计，各传感器的特性及其接口电路的设计。本仪器可对电子设备中热性能的各个参数，实行单点、多点巡回监测并提供显示，打印出各参数的功能，为电子设备进行可靠性热设计提供关键数据。     

动态模型试验孔隙水压测量系统

介绍了一种土工动态模型试验的数据采集系统。仪器采用AT89C51单片机作为控制器，主要包括小型高精度孔隙水压力传感器以及由CS5524 A／D转换器组成的多通道数据采集装置。要求在模型试验槽内水压变化时，能连续采集试验槽内各部分动态孔隙水压力变化。该系统结构简单、集成度高，自投入运行后，稳定可靠，取得了十分良好的应用效果。     

A Setup for Measuring Magnetic Properties of Magnetically Soft Materials in the Pulsed Remagnetization Regime

The modern technological level and trends of the development of magnetic techniques for measuring properties of magnetically soft materials (MSM) used in setups in whose cores magnetization is reversed in the pulsed regime have briefly been reviewed. A setup for measuring magnetic properties of MSM in a pulsed remagnetization regime for the pulse duration of 1–100 s and the magnetic flux of 10^–8–10^–5 Wb is described.     

Agilent34401A在沉积物热导率测量仪中的应用

以Agilent34401A为核心器件设计了沉积物热导率测量仪,实现了对多通道高精度温度和实际加热功率的测量。Agilent34401A的6位半数字万用表分辨率为1/(1.2×106),接近通用ADC的24位分辨率,电阻测量的精度可以达到0.01Ω,完全满足该系统数据采集的精度要求,为保证测量精度,其远程控制采用RS-232接口和SCPI命令。利用VC6.0编程平台,实现控制指令的发送和温度曲线的显示。