Amount of substance

News and Updates

After 90 Years, a Better Way to Measure the Composition of Paper

February 14, 2019

Researchers at the National Institute of Standards and Technology (NIST), in collaboration with the U.S. Government...

Better Flowmeters with the Big Blue Ball

February 24, 2017

Last year, upwards of 25 trillion cubic feet of natural gas were delivered to customers in the United States, and when...

How Sweet It Is: NIST Metrology and the Maple Syrup Industry

January 04, 2017

NIST is frequently asked to provide unusual, sometimes downright exotic, measurements and calibrations in support of U...

Redefining the SI Base Units

November 02, 2011

Note: Much more recent information is available about redefinition of the SI units. For a comprehensive general...

Publications

Certification of Standard Reference Material® 2193b Calcium Carbonate [used as saturated Ca(OH)2 solution]

May 16, 2019

Author(s):

Regina A. Easley, Jason F. Waters, William F. Guthrie

CCQM-K131 Low-Polarity Analytes in a Multicomponent Organic Solution: Polycyclic Aromatic Hydrocarbons (PAHs) in Acetonitrile

November 30, 2018

Author(s):

David L. Duewer, Lane C. Sander, Stephen A. Wise

Solutions of organic analytes of known mass fraction are typically used to calibrate the measurement processes used to determine these compounds in matrix...

CCQM-K95.1 Low-Polarity Analytes in a Botanical Matrix: Polycyclic Aromatic Hydrocarbons (PAHs) in Tea

November 30, 2018

Author(s):

David L. Duewer, Jacolin A. Murray, Laura J. Wood, Stephen A. Wise

Extraction, chromatographic separation, and quantification of low-concentration organic compounds in complex matrices are core challenges for reference...

CCQM K121 – Monoterpenes in Nitrogen at 2.5 nmol mol-1 Final Report

November 09, 2018

Author(s):

Christina E. Cecelski, George C. Rhoderick, Joseph T. Hodges, Antonio M. Possolo, Cassie A. Goodman, Yong D. Kim, Dal H. Kim, Sangil Lee, Nicholas Allen, Marivon Corbel, David Worton, Richard Brown, Paul Brewer

The growing awareness of climate change, and continuing concerns regarding tropospheric and stratospheric chemistry, will require future measurements and...

Projects & Programs

NIST PS1 Primary Standard for quantitative NMR (Benzoic Acid)

The "first-of-its-kind" in an entirely new class of reference material, NIST PS1 Primary Standard for quantitative NMR (Benzoic Acid) is now available! The PS...

Advanced Ambient Mass Spectrometry, Secondary Ion Mass Spectrometry and Ion Mobility Spectrometry

The Surface and Trace Chemical Analysis Group (STCAG) conducts both applied and fundamental research into the development, characterization, and analysis of...

International Comparisons for Chemical Measurements

Because of NIST's role as the National Metrology Institute (NMI) in the U.S., the Chemical Sciences Division's measurement capabilities must be benchmarked...

Tools & Instruments

Local Electrode Atom Probe Tomography (LEAP)

Field evaporates (with a voltage and laser pulse) a sharp tip-shaped specimen. Collects the ionization products in a position-sensitive, time-of-flight mass...

Material Analysis Using Neutron Depth Profiling

Light elements such as helium, lithium, boron, and nitrogen are essential constituents in materials that enable energy technologies; lithium ion batteries,...