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Summary & Details

New Defi nition of the Kilogram based on the Planck Constant and Its Application to Small Mass, Force and Torque Measurements

130年ぶりに改定されたキログラムの新しい定義とその微小量計測技術への応用

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Format: PDF

Price: Non-members (tax incl.)：￥1,100 Members (tax incl.)：￥880

Publication code: 20214713

Paper/Info type: Journal of Society of Automotive Engineers of Japan

Vol.75 No.10

Pages: 78-84(Total 7 p)

Date of publication: Oct 2021

Publisher: JSAE

Language: Japanese

Detailed Information

Category(J)	ホットトピックス Translation
Category(E)	Hot Topics
Author(J)	1) 藤井賢一
Author(E)	1) Kenichi Fujii
Affiliation(J)	1) 国立研究開発法人産業技術総合研究所
Abstract(J)	キログラムは人工物で定義される最後のSI基本単位として残っていたが、キログラム原器の質量安定性よりも高い精度でプランク定数を測定することが可能になり、130年ぶりにキログラムの定義が改定された。プランク定数から質量を導くための方法と、新しい定義にもとづく微小質量計測技術などについて解説する。 Translation
Abstract(E)	The kilogram had been the last SI base unit still defined by the material artifact. In November 2018, it was adopted to revise the definition by using a defined number of the Planck constant. The new definition comes into force on May 20th, 2019, the World Metrology Day. This historical change in the definition of the unit of mass was realized by the progress of recent measurement technologies in the X-ray crystal density and the watt (Kibble) balance methods. The new definition opens a new way for small mass, force and torque measurements in metrology.

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