物性测试仪对休闲食品酥脆性的测量

以市售不同形状的休闲食品为样品,以TA.XT2i/50型物性测试仪为仪器,探头和运行参数为试验因素,用仪器测量到的断裂力,变形距离等参数反映酥脆性,讨论了不同探头和不同测试参数对休闲食品酥脆性的影响规律,为休闲食品的研发、品质控制提供参考.研究结果表明,探头和测试参数对于酥脆性有显著影响.对于样品厚度较小的样品宜选用探头HDP/BSK;对于粒形、尺寸较小的样品宜选用P35探头.测试速度对于断裂力和变形距离影响不显著但对于峰面积、正峰数等指标影响显著.数据采集速率对于峰数、破断距离等参数影响显著.反映样品的内部结构宜选用较小的测试速度和较高的数据采集速率.     

流涎法塑膜制备过程中厚度在线检测方法

采用流涎法制备塑膜时,实时检测流涎口处半透明粘稠状塑膜厚度,从而及时调整生产工艺参数,以更好地提高塑膜的生产质量。本文采用光学在线测量法,利用直射式双反射光路激光三角法,建立振动状态下厚度测量模型,设计了厚度测量传感器,提出了两步标定法,保证半透明粘稠状塑膜厚度测量的准确性。实验表明,测量误差小于10μm,有效地消除了钢带在线振动产生的误差,该方法适用于流涎口处半透明粘稠状塑膜厚度的在线测量。     

基于单片机的多功能静电衰减测试仪

静电衰减时间常数是定量描述材料静电性能的重要物理量，可以通过测量静电电荷衰减时间达到测量静电的目的。在对现有静电测试方法以及各类静电衰减测试仪研究的基础上，基于单片机原理设计出多功能电荷衰减测试仪，它集充电法、电晕喷电法、摩擦法测试功能为一体，弥补了现有静电衰减测试仪功能单一的不足，利用单片机本身的定时计数功能得到精确的静电电荷衰减时间。     

常温液体粘度-密度-表面张力多参数快速测试仪的研制

本文研制了一种能够同时快速测量常温液体粘度、密度和表面张力的多参数综合测试仪。该测试仪以80C196KC单片机为检测与控制核心构建，粘度和密度的测量分别采用旋转柱体法和静力称衡法，表面张力采用一种新的测试方法——气泡幅频当量法。文中对各参数的测试原理、仪器总体结构、计算机测控单元等部分作了详细介绍，并给出了利用该仪器测定常见液体粘度、密度和表面张力的结果。试验结果表明，该测试仪具有较好的测试精度和工作稳定性。     

等容加热式饱和蒸汽湿度监测仪研制

针对饱和蒸汽的湿度难于测量的问题，本文提出了一种新型的测试方法并研制了基于微处理机的智能监测装置。与现有监测方法相比，本方法原理可靠、干扰小、测量精度高，仪表功能丰富而且探头结构简单。     

涂膜附着力测试仪校准方法的研究

涂膜附着力测试仪在水运工程等领域应用广泛,但是国内一直未发布与其专门相关的计量技术规范,缺乏完整的涂膜附着力测试仪计量测试方法。该文介绍了涂膜附着力测试仪的工作原理,提出了涂膜附着力测试仪的具体校准方法,选取样机进行了试验测量,对其测量不确定度进行分析,论证了校准方法的可行性,为涂膜附着力测试仪计量技术规范的编制提供了支撑。     

基于地源热泵的岩土热物性测试仪的研制与应用

地下岩土的热物性参数是地源热泵地热换热器的设计中所需要的很重要的参数。热物性参数的大小对钻孔的数量及钻孔的深度具有显著的影响,进而影响地源热泵系统的初投资。为了能够现场测量地下岩土的热物性参数,研制了便携式测试仪器,用该测试仪现场采集到的数据,再利用参数估计的方法确定地下岩土的热物性参数。概述了岩土热物性测试仪的检测原理、结构构成及检测结果,并指出了该检测仪的应用推广前景。     

高浓度粘稠物料管道输送系统压力测试及其装置

高浓度粘稠物料存在于工业领域的各个行业,本文对高浓度粘稠物料的流变学特性和管道输送特性的研究出发,设计制造了适合此类非牛顿流体的管道输送压力测试装置.文中详细介绍了测压装置的结构组成、主要功能以及测试方法,并对该装置的静态标定和动态标定过程及其结果做了分析,通过对多种高浓度粘稠物料的实验测定,表明该测压装置安装位置合理、测试数据全面、测试精度和性能可靠、测压装置的结构紧凑、安装方便,完全适用于高浓度粘稠物料管道压力的测量.     

安全阀静态性能检测方法的应用与分析

介绍了采用压力试验台和在线测试仪对安全阀静态性能的检测方法、测试系统和标准规定,分析和比对了阀门整定压力不同测试方法的测定数据及其准确性,为在线测试仪现场检测的应用提供了依据.     

ISF炉渣熔点测试方法的比较

本文介绍了测试ISF炉渣熔点的两种主要方法:物性法、铂片法,对比分析了GXA高温物性测试仪和铂片法测试仪两套测试设备的实验应用状况。     

智能油品质量在线监测仪的研制

提出了一种基于多传感器信息融合技术对油品质量进行在线监测的新方法，通过对粘度、温度、介电常数的测量，建立了神经网络油品质量状态监测模型，并给出了系统的设计方案。     

An automated setup for measuring the viscosity of metal melts

An automated setup for measuring the kinematic viscosity of metal melts using the method of damped torsional oscillations is described. The experimental errors in the viscosity determination are evaluated. The influence of the values of the damping factor, the oscillation period, and the sample radius and height on the value of the calculated viscosity error is analyzed. The methodological errors that are related to the consideration of the free-surface curvature, the thermal expansion, and the external friction in the inert atmosphere of the suspension system were analyzed. It is shown that these errors may have a significant effect on the viscosity determination accuracy. The viscosity of liquid lead in the range from the melting point to 1200°C is determined. The obtained data agree well with the literature data.     

基于FPGA ＆amp; DSP的流体粘度在线计算方法的研究

针对传统流体粘度测量实时性较差的问题,设计并实现了一种粘度计算方法。通过 FPGA计算驱动频率及驱动功率,并通过 MsBCP 接口将数据传输到DSP,利用 DSP 求解流体粘度,真正实现了粘度的在线测量。经试验验证本计算方法科学合理,可有效提高粘度计算实时性,提高流体粘度测量值的准确度。     

基于旋转法的发动机润滑油黏度检测技术研究

在传统旋转法基础上,提出一种新型的旋转式黏度在线测量方法。该方法利用流体力学相关理论对转子旋转时的黏滞力矩进行分析,通过建立传感器直流电机电流和油液黏滞力矩的关系来仿真计算油液黏度。研发一种发动机润滑油黏度在线检测传感器,通过高低温试验测试传感器对润滑油黏度的响应,并对传感器进行标定。结果表明,该传感器对油液黏度变化具有较快的响应与较高的灵敏度,结构简单,稳定可靠,克服了传统黏度计测量时间长、对环境要求苛刻、尺寸较大且价格昂贵的缺点。     

Adaptive sampling for coordinate metrology

An iterative sampling process for dimensional measurement is presented. The strategy is based upon the use of surface normal measurement data to develop an interpolating curve between sample points. The interpolant is used to select subsequent measurement targets iteratively. The process is repeated until the measurement converges to a complete and accurate evaluation of the surface. The required sample size is proportional to part quality. The most accurate parts will require the least sample points; whereas, lower quality parts will require a greater number of total samples. The method is particularly applicable to measurement of complex surfaces with coordinate measuring machines (CMMs).     

Simultaneous measurement of red blood cell aggregation and viscosity: Light transmission slit rheometer

Aggregation of red blood cells (RBCs) is a major determinant of blood viscosity. There have not been available techniques for measuring RBC aggregation and viscosity, simultaneously. A laser transmission technique has been combined with a slit rheometry, which shows significant advances in rheometer design, operation and data analysis. A laser beam traverses a blood suspension flowing through a slit and is scattered by RBCs in the volume. The transmitted light is captured by a photodiode, linked to a computer, while the differential pressure variation is measured by a pressure transducer. Both measurements of the laser-transmitted intensity and pressure with respect to time enable to determine the aggregation index and the viscosity. The advantages of this design are in its simplicity, i.e., ease of operation and no moving parts, low cost and a short operating time. In addition, the slit-flow aggregometer can be easily used in a clinical setting owing to the incorporation of a disposable element that holds the blood sample.     

逆向工程中不同数据采集方法的误差分析

数据测量是逆向工程的首要阶段，测量数据的好坏直接决定着后续数字化模型能否在误差控制范围内还原为已有的实物样件：现对三坐标测量机和结构光测量仪在进行数据采集过程中产生的测量误差进行了详细的分析，并提出了相应的解决方案，为最终构造出精度高、品质好的CAD模型奠定了基础。     

A magnetoelastic viscometer for on-line monitoring of viscosity of lubricating oils

The paper discusses the prospects for developing means for on-line measurement of the viscosity of lubricating oils, including diagnostic instrumentation based on magnetoelastic interaction. The theoretical basis for the development of magnetoelastic sensors and the main concept of measuring the fluid viscosity are presented. Two methods of measuring the viscosity are described. The first method is based on estimating variations in the natural frequency of oscillations of a sensitive element and the second involves analysis of the decay rate of the amplitude of oscillations. The design of the developed magnetoelastic sensor and the experimental results of comparing the two measurement methods are reported. The paper also presents the comparative results of measurement of the oil viscosity by a magnetoelastic sensor, a capillary viscometer, and a solid-state piezoacoustic sensor. It is shown that the reliability of the magnetoelastic sensor is high from the viewpoint of on-line monitoring; owing to its relatively low cost and ease of maintenance, it has wide potential for application in monitoring of lubricating oils in tribosystems.     

New Method of Measuring Permanent Viscosity Loss of Polymer-Containing Lubricants

An ultrahigh shear rate viscometer (USV) was used to measure the viscosity of polymer solutions. It was found that some polymer solutions in base oil, including those used as engine oil viscosity modifiers, show permanent viscosity loss when subjected to very high shear rates above 10⁶ s^?1. The USV was modified to automatically carry out a series of viscosity measurements on the same test lubricant sample. This enabled the accumulation of permanent viscosity loss to be measured over successive strain cycles.

As expected, permanent viscosity loss increased with both strain rate and molecular weight. When carried out at 5 × 10⁶ s^?1 and 100°C, the test was more severe than the Kurt Orbahn test because samples of lubricants subjected to the latter underwent further shear thinning in the USV.

The USV test appears to be a rapid and convenient way to quantify the permanent viscosity loss of polymer-containing lubricants for engine use, and a protocol to assess permanent viscosity loss (PVL) and permanent shear stability index (PSSI) based on viscosity measurements at 10⁶ s^?1 before and after shear thinning is outlined.

The study also shows that it is important to take into account possible permanent viscosity loss when measuring the viscosity of polymer solutions in very high shear rate viscometers such as the USV. This can be done by minimizing the amount of shear to which the lubricant is subjected or by taking successive measurements and subtracting the permanent viscosity loss taking place in each of the first few strain rate cycles.     

食用油品质的光学低相干外差干涉检测法

液体的折射率是一个重要的物理参数,在外界一定的条件下,掌握液体折射率及其变化,则可以了解其纯度、浓度等参数及品质。提出一种用低相干光外差干涉方法测量反复使用食用油的折射率,进而鉴别油的品质。实验以改进的迈克尔逊干涉仪为基础,将样品油放入测量臂光路中,当两束分别来自测量臂与参考臂的低相干光的光程接近相等时,会出现光外差干涉现象。利用光电探测器得到此干涉信号,根据前后相应的光程变化量,进而得到待测样品的折射率。食用油经反复加热1、2、3、5、7次后,葵花油的折射率分别为1.469 5、1.469 7、1.470 1、1.470 7、1.471 3,玉米油的折射率分别为1.468 8、1.469 1、1.469 4、1.470 1、1.471 1。结果表明,该方法可以准确测量出不同加热次数食用油的不同折射率,测量稳定性较高,能快捷、有效地鉴别反复使用的食用油品质。