中国计量科学研究院通过APMP同行专家评审

1999年,受原国家质量技术监督局委托,中国计量科学研究院参加了由国际计量局(BIPM)组织召开的38个米制公约国会议,并签署了《国家计量(基)标准互认与国家计量院签发的校准及测量证书互认》协议(MRA).根据协议,除承担参加国际关键比对并建立符合国际标准的检测服务质量体系外,国家计量科学院还可以要求所在洲的区域性计量组织(RMO)选择其它国家计量院(NMI)或者选派专家进行同行评审,以对其质量体系及最佳测量能力(CMC)进行旁证.得到亚太经济合作组织贸易与投资自由化便利化基金(APEC-TILF)的支持,亚太计量规范组织(APMP)决定在本地区组织同行专家以团队形式评审国家计量院,首先选择在中国计量科学研究院进行.     

NIM and CAST Sign CooperationAgreement

AQSIQ Minister Zhi Shuping met Dacian Ciolos, Commissioner for Agriculture and Rural Development of European Commission （EC） mad his entourage on July 23.     

Research on Time Keeping at NIM

UTC(NIM), which is developed and maintained by NIM, is the time and frequency primary standard in China. UTC(NIM) is generated originally by a clock ensemble, and is traced to UTC by participating in TAI cooperation with GNSS time and frequency transfer methods. TWSTFT earth station has been established at NIM new campus to join the Europe?CAsia link. In this paper, the new development on the realization of UTC(NIM), the GNSS time and frequency transfer and TWSTFT and our briefly future plan are introduced.     

中国计量科学研究院建成量子化霍尔电阻标准

国际计量委员会推荐，1990年1月1日起在世界范围内启用量子化霍尔电阻标准代替使用了几十年的电阻实物基准。中国计量科学研究院经过十几年的努力，在2003年建成了量子化霍尔电阻标准。课题组自主研制了能满足实际量值传递工作要求的量子化霍尔器件，并建成了高精度的低温电流比较仪，以把量子化霍尔电阻量值传递到日常检定工作中使用的十进电阻值。课题成果中有多项独创性的成就。目前所建量子化霍尔电阻标准的不确定度为10^-10量级，达到国际领先水平。     

国家级热能表检定装置的建立

文章介绍了中国计量科学研究院新建立的热能表检定装置的结构、原理和特点,并对装置的不确定度进行了详细的分析。该装置流量范围可达到(0.002~36)m3/h,温度范围可以从(10~85)℃。     

Optical Fiber Power Meter Comparison Between NIST and NIM

We describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and National Institute of Metrology (NIM-China). We report optical fiber-based power measurements at nominal wavelengths of 1310 nm and 1550 nm. We compare the laboratories’ reference standards by means of a commercial optical power meter. Measurement results showed the largest difference of less than 2.6 parts in 10³, which is within the combined standard (k = 1) uncertainty for the laboratories’ reference standards.     

我国的1V及10V约瑟夫森量子电压基准装置

文章描述了我国量子电压基准的建立、发展、现状和所取得的成果，以及与国际计量局进行基准关键比对的情况。     

Vacuum Radiance-Temperature Standard Facility for Infrared Remote Sensing at NIM

As infrared remote sensors are very important parts of Earth observation satellites, they must be calibrated based on the radiance temperature of a blackbody in a vacuum chamber prior to launch. The uncertainty of such temperature is thus an essential component of the sensors’ uncertainty. This paper describes the vacuum radiance-temperature standard facility (VRTSF) at the National Institute of Metrology of China, which will serve to calibrate infrared remote sensors on Chinese meteorological satellites. The VRTSF can be used to calibrate vacuum blackbody radiance temperature, including those used to calibrate infrared remote sensors. The components of the VRTSF are described in this paper, including the VMTBB, the LNBB, the FTIR spectrometer, the reduced-background optical system, the vacuum chamber used to calibrate customers’ blackbody, the vacuum-pumping system and the liquid-nitrogen-support system. The experimental methods and results are expounded. The uncertainty of the radiance temperature of VMTBB is 0.026 °C at 30 °C over 10 μm.     

光电比较仪(或高温计)系统非线性测量装置

本系统地介绍了新研制的光电比较仪（或高温计）系统非线性测量装置。新装置采用双光源单光路设计,具有独立于被测对象和不失真的特点。利用该装置对基准光电比较仪和标准光电高温计进行了系统实验,测量不确定度达到０．０１％。利用该装置测量的数据已应用于国际计量局（ＢＩＰＭ）和亚太计量规划组织（ＡＰＭＰ）主办的国际比对中。     

Counselors of the State Council Visit NIM for Developmental Inspirations

<正>A group of counselors of the State Council gathered at the National Institute of Metrology(NIM)recently to launch a special investigation on the national metrological development under the background of the reform of international metrological units.Zhang Gang,Counselor to the State Council and former Chief Engineer of AQSIQ,chaired the launching meeting followed by a     

125I放射性溶液活度测量国际比对

2004年6—8月，中国计量科学研究院电离辐射处参加了国际计量局（BIPM）组织的5I放射性溶液活度测量国际关键比对。我们采用KX射线和γ射线的探测效率符合相加原理，选用4π井形NaI晶体测量装置对^125I的活度进行绝对测量。测量结果与平均值相差1．3％．     

Global reconstruction from nonstationary data

One-dimensional time series of a dynamical system with slowly varying parameters are investigated. For estimation of the characteristics of the attractors of such a system which exist for fixed values of the parameters, it is proposed to “cut out” from the time series short segments that belong to the individual attractors and to use them to reconstruct a model dynamical system. Pis’ma Zh. Tekh. Fiz. 25, 74–81 (May 26, 1999)     

NIM铯原子喷泉频率基准的设计与初步结果

中国计量科学研究院设计与建造了作为新一代频率基准的铯原子喷泉,并已完成一系列元、部件的性能测量。在磁光阱中观测到冷原子云,其直径为１．５ｍｍ,原子温度≤１５０μＫ。下一步将获得为喷泉钟设计的光学粘团。     

Realization of ITS-90 Above the Silver Point at the NIM

The high-temperature primary standard system was gradually improved at the National Institute of Metrology (NIM) in China after 2004. A new primary standard pyrometer (PSP) was developed, one with a size-of-source effect of 1 × 10^?4, and regional thermostats for interference filters, photoelectric detectors, and I/V converters. The relative spectral responsivity of the entire PSP was calibrated by means of a new facility. A new LED-based measurement facility and novel systematic error correction model were utilized to characterize the PSP nonlinearity and extend the photocurrent to PSP temperature readings of about 2680 °C. As an improved scheme, the fixed-point blackbody pyrometer assembly was utilized to realize and disseminate the International Temperature Scale of 1990 above the silver point. This scheme can avoid the influences of instability and inhomogeneity of tungsten strip lamps and corrects pyrometer drifts, thereby improving the realization uncertainty and simplifying the transfer chain. The expanded uncertainties of the scale realization ranged from 0.04 °C at the silver point to 0.48 °C at 2474 °C.     

A precise measurement of QHR at NIM [quantized Hall resistance]

Equipment for precise measurement of the quantized Hall resistance (QHR) at the National Institute of Metrology (NIM), Beijing, China, is described. The essential parts in this equipment are a resistance comparator of one-to-one ratio with a comparison uncertainty of 3×10^-8 and two specially designed resistor networks used for determining of the ratio between 12906.4035 Ω of QHR at i=2 and 10 kΩ or 1 kΩ. The transfer procedure from QHR to 10 kΩ or 1 kΩ can be completed easily with this equipment by a few one-to-one comparisons with a total uncertainty of 5×10^-8     

NIM用计算电容测定的量子化霍尔电阻的SI值

量子化霍尔电阻的ＳＩ值的准确测定对进一步改进冯·克里青常数的准确度及国际基本物理常数平差均有重要意义。中国计量科学研究院于１９９４年春用计算电容测定了量子化霍尔电阻的ＳＩ值，测得ｉ＝１时的量子化霍尔电阻的ＳＩ值为ＲＨ＝２５８１２．８０８４（３４）Ω，其不确定度为１．３×１０－７（１σ）。     

~(125)I放射性溶液活度测量国际比对

2004年6-8月,中国计量科学研究院电离辐射处参加了国际计量局(B IPM)组织的125I放射性溶液活度测量国际关键比对。我们采用KX射线和γ射线的探测效率符合相加原理,选用4π井形NaI晶体测量装置对125I的活度进行绝对测量。测量结果与平均值相差1.3%.