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The National Physical Laboratory (NPL) Mk II watt balance made an initial series of measurements of Planck's constant in the period from October 2006 to March 2007. The results of these measurements significantly differ from those recently published by the National Institute of Standards and Technology (NIST). Modifications have been made to the apparatus to reduce the most significant uncertainties...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.