ID
× COMMENTARYCOVER STORYIN THE NEWSNEWSFRONTSCHEMENTATOR + Show More BUSINESS NEWSTECHNICAL & PRACTICALFEATURE REPORTFACTS AT YOUR FINGERTIPSTECHNOLOGY PROFILESOLIDS PROCESSINGEQUIPMENT & SERVICESFOCUSNEW PRODUCTS + Show More SHOW PREVIEWS

Comment PDF Business & Economics

Facts at your Fingertips: Redefining the Kilogram Standard

By Scott Jenkins |

The kilogram is the last of the SI units (International System of Units) still defined by a physical object, rather than defined in terms of universal fundamental constants of nature. However, this will change in November 2018, as a multi-year effort culminates in the adoption of a new definition for the kilogram that is based on Planck’s constant. This one-page reference describes the effort to redefine the kilogram standard, shifting the definition from a physical object, which can change over time, and to a definition according to stable and reproducible constants of nature. The kilogram is currently defined as the mass equal to a polished cylinder of platinum and iridium known as the International Prototype of the Kilogram (IPK; photo). Cast in 1879, it is currently housed at the Bureau International des Poids et Mesures (BIPM; Sèvres, France; www.bipm.org). According to the U.S. National Institute of Standards and Technology (NIST; Gaithersburg, Md.; www.nist.gov), “The accuracy of every measurement of mass or weight worldwide depends on how closely the reference masses used in those measurements can be linked to the mass of the IPK” [1]. BIPM[/caption] Re-defining the kilogram With improved measurement technologies,…
Related Content
Weighing Equipment Selection
The number of options available for scales and weighing equipment can make it difficult to determine which instruments will offer…

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
5 ways to Optimize Production of Polymers and Intermediate Petrochemicals
7 Ways to Achieve Process Safety in Chemical Production
Five Reasons Why Chemical Companies Are Switching to Tunable Diode Laser Analyzer Technology
Simplify sensor handling and maintenance with ISM
Three reasons to measure pH in-line

View More

Live chat by BoldChat