Preparation for a Comparison of Platinum-iridium Kilogram Mass Standard among Nmis in Apmp
نویسندگان
چکیده
− The kilogram is unique among the base SI units in being the only one defined by an artefact. A major problem with maintaining the traceability of the mass scale is the inherent instability of the kilogram artefacts. To resolve the problem, there had been done a comparison of the values of the national standard kilogram of 18 European National Metrology Institutes (NMIs) by National Physical Laboratory (NPL) in England. The similar comparison in APMP is needed to plan as a pilot study. The ten institutes of APMP are participated in this pilot study. KRISS in Korea and NMC/ASTAR in Singapore act as a pilot and a co-pilot laboratory respectively. The travelling standard (No. 651) used for comparison among European NMIs is provided by NPL. In this paper, the preparation of comparison and the interim result for stability of the travelling standard at KRISS will be presented.
منابع مشابه
The Dissemination of Mass in the United States: Results and Implications of Recent BIPM Calibrations of US National Prototype Kilograms
The National Institute of Standards and Technology (NIST) is responsible for the dissemination of the unit of mass within the United States of America through the national prototype kilogram K20 and its check standard K4. These platinum-iridium artifacts have been in use since 1889 and are periodically sent to the International Bureau of Weights and Measures (BIPM) for recalibration. The follow...
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