中国参加温度关键比对结果分析

本文介绍了国际计量委员会(CIPM)组织国际关键比对的背景和已经开展的温度比对项目。对中国计量科学研究院参加的温度比对项目进行了系统介绍和结果分析。     

光度计响应度国际比对方法和结果

介绍光度与辐射度咨询委员会（ＣＣＰＲ）国际比对项目－光度计响应度的比对方案和在中国计量科学研究院（ＮＩＭ）的复现方法，并对国际比对做了简要分析。     

国际计量比对数据库投入使用

由ＮＩＳＴ开发 ,并经国际计量局认可的国际计量比对数据库已在Ｉｎｔｅｒｎｅｔ网络上投入使用。１９９９年１０月由３８个国家签署了“相互承认国家计量标准”的协议 ,从而建立了上述国家计量科研机构间进行关键项目比对的正式系统。根据国际计量局的报告 ,已经和正在进行的循环比对项目约１３０种。计量专家组将评定收入数据库的比对结果的可靠性。该数据库还将扩展到其它国家。国际计量比对数据库投入使用     

直径测量国际比对中标准器和测量方法的统一与讨论

国际比对是国际计量局的重要工作任务之一,比对项目由国际计量局的各个专业咨询委员会确定.由于直径尺寸是精密制造业中一项关键的测量内容,国际计量局长度咨询委员会(BIPM CCL),将"直径标准尺寸"列为长度国际关键比对项目(包括内直径和外直径测量).参加比对的实验室为12个国家的计量院.关于直径标准器(环规和塞规)和测量问题等,参加比对的实验室进行了长时间的讨论,最终确定了比对标准器规格尺寸、测量位置、温度修正以及测量和评定方法.     

亚太实验室认可合作组织 APLAC M024光滑塞规校准能力国际比对

亚太实验室认可合作组织APLAC进行第24次国际实验室比对———M024光滑塞规校准能力国际比对。辽宁省计量科学研究院作为中国合格评定国家认可委员会（ CNAS）推荐的3个实验室之一参加了此次比对项目。文章介绍了比对方法、比对过程、比对数据及不确定度分析。统计结果表明,实验数据为满意。     

纳米尺度线宽的测量与Nano1国际关键比对

现代集成电路制造业、数据存储工业和微机电系统等行业的不断发展,对纳米尺度线宽的测量提出了越来越高的要求.目前的一些测量方法分别存在各自的缺点与不足,在缺少更高准确度计量标准的情况下,往往采用比对的方法使计量结果趋于一致.国际计量局在1998年把纳米尺度线宽计量确定为纳米尺度基本特征国际关键比对项目之一.文章对它的主要研究内容以及进展情况作了介绍.     

纳米尺度线宽的测量与Nanol国际关键比对

现代集成电路制造业、数据存储工业和微机电系统等行业的不断发展，对纳米尺度线宽的测量提出了越来越高的要求。目前的一些测量方法分别存在各自的缺点与不足，在缺少更高准确度计量标准的情况下，往往采用比对的方法使计量结果趋于一致。国际计量局在1998年把纳米尺度线宽计量确定为纳米尺度基本特征国际关键比对项目之一。文章对它的主要研究内容以及进展情况作了介绍。     

绝对重力仪国际比对新动态

全球绝对重力仪国际比对活动从1981年起每隔4年在法国国际计量局举办。近两年来,该比对活动发生了一些变化,同时,区域性绝对重力仪国际比对活动日益兴起。中国计量科学研究院代表我国参与了这方面的工作,并介绍了中国计量科学研究自主研制的NIM-II型绝对重力仪参加2009年第8届全球绝对重力仪国际比对的情况和结果     

0℃～419.527℃标准铂电阻温度计大区比对的评述

2000年,国家质量技术监督局计量司下达了大区级计量技术机构间标准铂电阻温度计的比对任务。中国计量科学研究院作为主导实验室制定并完成了此次大区比对的工作细则和最终的数据处理和评估。共有7个大区级计量技术机构的温度实验室参加了比对工作。通过对已公布的结果进行分析和评述,使大家了解国际ITS-90温标在中国的实施现状,指导今后进一步提高ITS-90复现和维护水平,从而确保各大区级计量技术机构温度实验室在0℃～419．527℃范围内温度量值的准确传递和可靠的量值溯源。     

"二等水银温度计量值全国比对"与湖北温度计量

介绍了"二等水银温度计量值全国比对"的情况和湖北省计量测试技术研究院参加比对的结果,分析了比对中存在的问题及处理办法,阐述了湖北温度计量的发展及未来展望.     

Determining Reference Values and Degrees of Equivalence in Key Comparisons

Various approaches are considered to determining the reference value in key comparisons. The purposes of key comparisons are compared with those of other interlaboratory experiments. Models are proposed for the key comparison data in accordance with the purposes of the key comparisons and available a priori information on those data.     

Analysis and Some Aspects of the Results of Key International Comparisons in the 83.8058–933.473 K Temperature Range

Results of the KC3 key international comparisons of temperature measurements, in which 15 national metrological institutes from Europe, America, Asia and Australia participated, are presented. The maximum differences between the results obtained by national metrological institutes amounted to 6, 3, 2, 3 and 1 mK, at the freezing points of Al, Zn, Sn and In and at the melting point of Ga respectively. It is shown that the results obtained at all the compared points at the D. I. Mendeleev All-Union Scientific Research Institute of Metrology are close to the results obtained at the NIST – the coordinator of the comparisons, and are near the mean values obtained by all the participants.     

A Trial Intercomparison of Humidity Generators at Extremes of Range Using Relative Humidity Transmitters

In order to effectively implement the Mutual Recognition Arrangement (MRA) of the International Committee for Weights and Measures (CIPM), national metrology institutes (NMIs) are required to support their claims of calibration and measurement capability (CMC) with a quality system compliant with ISO/IEC 17025, and with suitable evidence of participation in key or supplementary comparisons. The CMC review process, both at regional and inter-regional levels, uses criteria that combine the provisions mentioned above, together with additional evidence demonstrating scientific and technical competence of the institutes. For dew-point temperatures, there are key comparisons in progress under the Consultative Committee for Thermometry (CCT) and under the European regional metrology organisation (EUROMET), together with information available on past regional supplementary comparisons. However, for relative humidity there are, to date, no such comparisons available to support CMC entries. This paper presents and discusses the results of a preliminary investigation of the use of relative humidity and temperature transmitters in order to determine their suitability for the intercomparison of standard humidity generators in support of CMC claims for the calibration of relative humidity instruments. The results of a recent bilateral comparison between 2 NMIs at the extremes of the range up to 98%rh at 70 °C, and down to 1%rh at −40 °C are reported. Specific precautions and recommendations on the use of the devices as transfer standards are presented.     

Statistical Interpretation of Key Comparison Reference Value and Degrees of Equivalence

Key comparisons carried out by the Consultative Committees (CCs) of the International Committee of Weights and Measures (CIPM) or the Bureau International des Poids et Mesures (BIPM) are referred to as CIPM key comparisons. The outputs of a statistical analysis of the data from a CIPM key comparison are the key comparison reference value, the degrees of equivalence, and their associated uncertainties. The BIPM publications do not discuss statistical interpretation of these outputs. We discuss their interpretation under the following three statistical models: nonexistent laboratory-effects model, random laboratory-effects model, and systematic laboratory-effects model.     

CCT-K7水三相点容器国际关键比对

在国际互认框架内,国家计量标准的国际等效性是通过国际计量委员会（CIPM）的咨询委员会组织的一系列国际关键比对来确定的。温度咨询委员会（CCT）委托国际计量局（BIPM）作为主导实验室组织了由20个国家实验室参加的CCT-K7水三相点容器国际关键比对。比对结果表明：这些国家基准水三相点值在0．171mK范围内一致。此外,为了减小国家实验室复现水三相点的系统差,需要进一步研究同位素组成对水三相点温度的影响以及同位素修正。     

Research on key technologies of FEM simulation of temperature field in the process of quenching

In this paper, some key technologies of computing the quenching temperature field are given. According to the characteristics of quenching process, a new method of computing phase-transformation latent heat is presented to ensure the computation accuracy of temperature. The phase-transform latent heat is regarded as the internal heat source because it can result in the rise of temperature in the process of cooling. A new method of self-control and adaptive time-step is presented in this paper. This method can be used to compute the time-step according to maximum and minimum difference values of the temperature field between the previous simulating step and the current simulating step. A finite element method (FEM) software for evaluating the temperature and the phase-transformation is developed by using the methods presented in this paper, the lump parameters method and fine mesh method. The experimental results or analytical values of two cases are used to check the accuracy of FEM simulation. The comparisons show that the simulation results of FEM software are consistent with experimental results or analytical values.     

0-5kN-10kN力值国际关键比对的评述

从1999年起,国际计量局（BIPM）质量及相关量咨询委员会（CCM）组织了0-5kN．10kN（CCM．F-K1）、0-50kN-100kN（CCM.F-K2）、0-500kN-1000kN（CCM．F-K3）和0-2MN．4MN（CCM．F．K4）等4个量程的力值国际关键比对,旨在保证世界各国间力值的准确一致。中国计量科学研究院作为中国国家实验室参加了全部4项力值国际关键比对。介绍了CCM．F-K1．a0-5kN．10kN力值国际关键比对的比对方法和比对结果,对提高我国力值计量领域的研究水平,以后组织或参加力值国际和国内力值比对及进行各实验室问能力验证具有一定的指导意义。     

Calculation of the reference value of key comparisons from the results of measurements made by different absolute methods

Two algorithms for processing the data of key comparisons in which the participants use not one but several absolute measurement methods are considered. Some advantages are demonstrated for an algorithm in which the results of measurements are first processed according to groups classified by the method, after which the reference value of key comparisons and its uncertainty are determined. __________ Translated from Izmeritel’naya Tekhnika, No. 7, pp. 17–20, July, 2007.     

低温运载火箭POGO抑制系统研究

在调研国外低温运载火箭抑制纵向耦合振动方案及结构的基础上,对各种可行性方案进行分析研究,从贮气型结构的气腔结构选型、消除温度对能量值的影响、低温绝热、低温结构密封、低温充气测压方案及注气型结构的注入气总量和单位流量的控制、充气测压方案等关键难点技术分析,对比双层整体套装波纹式蓄压器、双侧金属膜盒式蓄压器、囊式蓄压器、注气型蓄压器的先进性、继承性、复杂性、工作寿命、工艺性、经济性、使用维护性、可靠性等方面情况,分析对比结果表明,双侧金属膜盒式蓄压器是中国低温运载火箭抑制纵向耦合问题的最为合理可靠的方案.     

Recent developments in BIPM voltage standard comparisons

The Bureau International des Poids et Measures (BIPM) carries out a number of comparisons of dc voltage standards with National Metrology Institutes (NMIs). These take the form of on-site comparisons of Josephson standards or bilateral comparisons using traveling standards based on Zener diodes. This paper describes some of the new procedures used in both types of comparison and presents some results of five recent BIPM key comparisons