黑体式光电高温计的研制

黑体式光电高温计采用基于黑体辐射的光电测量方法,具有测量准确、成本低等优点,在许多场合可以替代昂贵的贵金属热电偶.介绍了其测温原理、硬件电路、软件流程,采用MSC1211单片机作为信息处理单元,结果表明测温准确,性能可靠,多种信号输出形式极大地方便了用户使用.     

半导体功率器件测试用脉冲高压源的设计与实现

为满足精密测温需求,解决标准光电高温计测温结果易受环境温度影响的问题,设计多点控温系统,该系统通过多点布控的方式实现内层壳体整体控温,应用薄膜加热片作为控温元件,并采用自主设计的控温电路。开展试验对该系统的控温稳定性、重复性以及标准光电的测温稳定性进行了验证,结果表明多点控温系统稳定后2.5 h波动0.09 ℃,三天控温重复性0.1 ℃。室温环境下,应用标准光电高温计测试银固定点黑体辐射源,使用多点控温系统与不使用多点控温系统时的测温波动分别为0.1 ℃和0.7 ℃。本文研制的标准光电高温计多点控温系统具有稳定性好、体积小、重量轻、易于控制等优点,能够有效满足标准光电高温计的精密测温需求,为促进国产精密测温仪器的性能提升起到推动作用。     

一种新型红外多谱段高温计的研究

基于辐射学原理的辐射高温计是一种非常实用的非接触式表面温度测量仪器。但是,在许多的实际情况下,辐射测温的精度受到一定的影响,这主要是由于被测试件表面发射率的不解定性、较强的环境辐射等。本在研究了复杂环境中的辐射状况的基础上,提出了一种新的测温模型,并在此基础上建立了多谱段红外辐射高温计系统。实验证明,在环境辐射较强时,这种新型高温计系统达到了令人满意的结果。     

光电高温计的不同设计对辐射源尺寸效应的影响

辐射源尺寸效应是影响光电高温计分度与测温不确定度的重要因素之一，本文设计了专门进行辐射源尺寸效应实验的光电高温计。采用间接法分别对MgF2和AR14两种镀膜物镜、不同直径孔径光阑和光阑位置对光电高温计辐射源尺寸效应的影响进行了实验测量。辐射源直径为50mm时，该光电高温计的辐射源尺寸效应小于2×10^-4，具体数值与物镜表面反射比有关，与孔径光阑位置无关。     

新型精密光电高温计

根据温标传递的特点和需要,设计了新的精密光电高温计。该高温计测量黑体的光谱辐射亮度,结合有效波长原地测量技术,直接依据Planck辐射定律计算被测温度,具备单一参考点分度确定温标的技术能力。该高温计测温范围为800℃～2200℃,在小目标和窄谱带的测量条件下,具有分辨率高、辐射源尺寸影响小、自动化测量等特点。在900℃时温度分辨率为0 01℃。在800℃～2200℃温度范围内,置信水平为0 99时,扩展不确定度为1 0℃～2 4℃。结构参数和性能测试表明,精密光电高温计不仅适用于温度精密测量,而且可作为温标的传递标准。     

基于LabVIEWRT9032光电高温计增益比的测量系统

RT9032光电高温计是辐射测温常用的计量标准器,对其电路中增益比的测量决定了其测温的准确性.建立一个针对RT9032光电高温计电流放大器量程间的增益比测量系统.使用开发平台LabVIEW和GPIB接口与RT9032、Keithley6430搭建这套软件系统,并利用LabVIEW语言实现测量过程自动化.     

光谱光电高温计的波长和带宽参数对温度测量准确度的影响

本文依据普朗克黑体辐射定律,研究了光谱光电高温计的光谱波长和光谱带宽对温度测量准确度的影响,导出了温度测量误差关系式,并在钢铁热处理实验中进行了验证,介绍了减少外界环境对温度测量准确度干扰的几种实用方法,讨论了温度测量的方式所带来的不同测量误差,为钢铁工业测温正确使用光谱光电高温计提供了有用的参考。     

新型精密光电高温计

一、引言目视光学高温计是高温温标量值传递的主要标准器。但是由于以人的眼睛作为探测器及仪器的结构缺陷,使测量精度受到一定限制。因此,为提高量值传递及高温测量的精度,我们研制成功了光电高温计,取得良好的效果。该光电高温计,在900℃～2000℃范围内,其测温灵敏度可达0.1℃～0.2℃。测量准确度均为±1℃～1.5℃。二、光电高温计工作原理光电高温计的测温方法与目视光学高温计一样,它是应用光测高温技术进行测量的。本仪器的工作原理如图1所示。被测温的     

光电高温计在使用中存在的问题及改进

为了解决标准光电高温计在量值传递中存在的问题,通过在黑体炉的腔口前使用加装特制的高质量光阑的办法,来达到改进现有测量方法、消除量传偏差的目的,保证了标准光学高温计和标准光电高温计在辐射测温仪计量器具检定系统量值传递和溯源链中量值的一致性.     

关于光学高温计检修中几种常见问题的分析和处理

本文根据光学高温计的原理分析了光学高温计在检修中几种常见的问题及处理方法,对于我们提高检测质量和数据准确、可靠具有及其重要的作用.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.