热电偶自动检定装置的研制

我们根据我国热电偶检定规程的技术要求,研制成了由微机控制的热电偶自动检定装置。它可对热电偶检定过程的每一环节进行实时控制,即检定炉温度的设定与控制,温度变化率的监测与判断,数据采集与处理,直至检定证书的打印等,全部实现了自动化。经半年运行考察与鉴定,该装置可检定工业用热电介,二等标准热电偶。     

热电偶自动检定系统

热电偶是我厂氧化铝生产中的重要测温元件,其测量的准确性直接影响着产品的质量。为了给生产提供一个准确可靠的测量数据,我们对传统的热电偶检定装置进行了更换和升级,采用了西航电子仪器厂生产的RZJ—2D型热工全自动检定系统,实现了热电偶检定过程的全部自动化,即自动控温、自动检定、自动数据处理、自动打印检定结果。1 系统工作原理如图1所示,被测信号通过多路开关进入采样数表,数表将其采样值通过IEE—488通信电缆传送到计算机,计算机根据程序设计要求,通过主机箱控制调功器的输出功率,保证检定炉按要求进行升温变化。同…     

热电偶检定炉温场均匀性测试方法探讨

测试温场的目的就是找出检定炉有效工作区域内任意两点间的最大温差，即温场均匀度。前提是测量过程中或在测量任意点的温度时，都应在设定的同一个温度下进行。为此，首先选两支标准热电偶，一支作标准偶（固定偶），另一支作测量偶（移动偶）。测量偶在检定炉轴线上移动测量各点的热电动势，求出轴向温场的分布情况．如图1、图2所示。根据检定炉端口尺寸，再选两个直径与之对应的定位块，如图3所示。     

短型热电偶测温装置的整体检定

为解决短型热电偶示值检定中 ,因参考端温度补偿难以准确测量 ,给检定结果带来的误差 ,将短型热电偶测温装置进行整体检定 ,从而解决了短型热电偶的示值检定问题。     

VSTR-1002工业铂／铜电阻自动检定装置的误差分析与改进

本文介绍了工业铂／铜电阻自动检定装置的组成及测量数据的处理方法,并采用两种不同的实验方案进行试验,通过两组试验测量数据的对比,分析了这套自动检定装置的测量误差来源。提出了改善装置测量准确性的方法。     

热电偶、热电阻自动检定装置的选型

热电偶和热电阻的测试工作是一项繁琐而费事的手工工作,需要花费大量的人力,随着科学技术的发展,对温度的测量尤其是高温的检测提出了越来越高的要求,传统的测量方法,已无法适应诸多领域对温度计量的要求。自动测量系统全过程无需值守,既提高了热电     

双路并行汽车罐容量自动检定装置

将两套标准金属容器并行使用,解决了检定速度慢和检定过程中前后仓不平的问题。将传统容量比较检定方法与现代化控制技术结合,充分发挥PLC和组态软件的特长,实现了检定过程自动化;进行装置测量不确定度评定,验证了装置的测量能力。与传统手动装置进行比较,结果表明双路并行装置快速、准确、可行。     

玻璃液体温度计自动检定装置测量结果的不确定度评定

依据JJG 130-2011《工作用玻璃液体温度计》检定规程的方法和要求,在研制的温度计自动检定装置上对玻璃液体温度计进行检定,对人工和自动检定两种测量结果进行了不确定度的评定,着重分析测量值的不确定度来源与评定方法,评定结果表明自动检定装置测量结果的不确定度小于人工检定方法,能提高测量结果的质量水平。     

热电偶自动检定系统的开发

在传统的检定过程中,用电位差计通过手动转换开关读取在不同检点的标准电偶、被检电偶的热电势,然后根据检定规程对检定数据进行手工统计处理,并把结果填表记录。上述检定步骤中具有引起误差的环节,而且手工操作效率低,劳动强度大,计算量繁多。另外,由于人工读数时间长,很难保证等精度条件。由此可见,传统的检定方法已经很难适应现代化质量管理的需要,对它进行改造是完全必要的。1．热电偶自动检定系统的工作原理本系统由微机系统、温度控制系统及数据采集系统组成,系统框图见图一微型计算机主要完成整个系统各个部分的控制、协…     

晶体管开关时间参数测量标准装置

本文介绍晶体管开关时间参数测量标准装置，该装置应用计算机控制技术，按照国家标准规定的测量原理和方法，进行稳定、可靠、准确的晶体管开关时间参数的测量，实现对晶体开关管的动态参数的自动检定、数据处理和证书打印。     

Design for volume optimization of packaging for durable goods

In the literature, there are several authors arguing for the optimization of the packaging volume as an important factor in distribution efficiency. Within the context of packaging of durable goods, these authors present significant economic savings, usually illustrated by qualitative examples of redesigns. So far, these papers are limited to: (a) the economic aspect of volume (b) packaging for which the main functionality is distribution‐related, and (c) mostly qualitative empirical data. This current paper aims to contribute to this literature by: (a) arguing that volume is also a significant factor from an environmental perspective (b) including packaging for which the main functionality is marketing‐related, and (c) presenting quantitative data of over 1000 packed durable goods, covering consumer electronics, domestic appliances, toys, power tools and furniture. Several strategies for volume optimization are discussed in relation to different packaging functionalities. Copyright © 2011 John Wiley & Sons, Ltd.     

Chemical methods for searching for evidence of extra-terrestrial life

This paper describes the chemical concepts used for the purpose of detecting life in extra-terrestrial situations. These methods, developed initially within the oil industry, have been used to determine when life began on Earth and for investigating the Moon and Mars via space missions. In the case of Mars, the Viking missions led to the realization that we had meteorites from Mars on Earth. The study of Martian meteorites in the laboratory provides tantalizing clues for life on Mars in both the ancient and recent past. Meteorite analyses led to the launch of the Beagle 2 spacecraft, which was designed to prove that life-detection results obtained on Earth were authentic and not confused by terrestrial contamination. Some suggestions are made for future work.     

Optimum policy for warrants for and design of guardrails

An optimum policy for the warrants for and the design of guardrails based on benefit maximizing criteria is presented. It is shown that the strength, the number of classes of standards, and the location of guardrails should be determined simultaneously with due consideration for the nation-wide distribution of roadside dangers and the impact of colliding vehicles. Dynamic programming is used for optimization.     

船舶与集装箱用钢板预处理过程中所用磨料的对比

对船舶与集装箱用钢板涂装前预处理过程中，抛（喷）丸清理（除锈、刻蚀）用各种磨料的性质、磨料硬度与侵入性及耐久性（寿命）的关系、磨料的形状与清理效果的关系、磨料的粒度与覆盖率、冲击功的关系作了对比分析，提出了合理选用磨料的原则。     

Optics Concept for a Pair of Undulator Beamlines for MX

We describe a concept for x-ray optics to feed a pair of macromolecular crystallography (MX) beamlines which view canted undulator radiation sources in the same storage ring straight section. It can be deployed at NSLS-II and at other low-emittance third-generation synchrotron radiation sources where canted undulators are permitted, and makes the most of these sources and beamline floor space, even when the horizontal angle between the two canted undulator emissions is as little as 1-2 mrad. The concept adopts the beam-separation principles employed at the 23-ID (GM/CA-CAT) beamlines at the Advanced Photon Source (APS), wherein tandem horizontally-deflecting mirrors separate one undulator beam from the other, following monochromatization by a double-crystal monochromator. The scheme described here would, in contrast, deliver the two tunable monochromatic undulator beams to separate endstations that address rather different and somewhat complementary purposes, with further beam conditioning imposed as required. A downstream microfocusing beamline would employ dual-stage focusing for work at the micron scale and, unique to this design, switch to single stage focusing for larger beams. On the other hand, the upstream, more highly automated beamline would only employ single stage focusing.