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Taiwan purchases silicon sphere from PTB

PTBnews 2.2019

Taiwan has had its own silicon sphere since 24 November 2018. After the revision of the International System of Units (SI), it is possible to use this sphere to realize the unit of mass. The sphere – or to be more precise: the isotope-enriched 1 kg 28Si mass standard – was handed over to the Industrial Technology Research Institute of Taiwan (ITRI) by PTB President Prof. Joachim Ullrich and by the Head of the competent Division, Frank Härtig. However, the Taiwanese scientists were provided not only with the silicon sphere itself, but also with the know-how that is necessary to measure the surface layer.