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P. Richard

Kilogram prototype number 38 is one of the 40 initial replicas of the international prototype kilogram.
Posted inScience Updates

Universal Units Reflect Their Earthly Origins

by M. J. Van Camp, P. Richard and O. de Viron 14 November 201828 October 2021

On Friday, the kilogram will join its fellow metric units with a definition based on fundamental physical constants, but these units maintain links to their roots in the geosciences.

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