https://www.nist.gov/news-events/news/2014/01/new-value-planck-constant-may-hasten-electronic-kilogram
New Value for the Planck Constant May Hasten Electronic Kilogram | NIST
Feb 3, 2025 - After two years of difficult and meticulous work examining, refurbishing, and testing the aging workhorse watt balance called
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