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News and Updates

Identifying Individual Molecules: NIST Study Suggests How to Build a Better ‘Nanopore’ Biosensor

April 27, 2021

Researchers have spent more than three decades developing and studying miniature biosensors that can identify single molecules. In five to 10 years, when such

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 Publishing Office (GPO), have developed a

NIST researcher Jodie Pope with the big blue ball

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 it changed hands, nearly every cubic foot

Projects and Programs

Standards for Metagenomics

Metagenomics, or identifying the organisms present in a sample through DNA-based analysis, is a revolutionary technology made possible through advances in

Thermal Desorption Ambient Mass Spectrometry

Thermal desorption ambient mass spectrometry decouples analyte desorption and ionization. Here, analytes are thermally desorbed directly from a primary surface

Time-of-Flight Secondary Ion Mass Spectrometry

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) employs a pulsed primary ion beam and a time-of-flight mass analyzer for the detection of molecular

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

Publications

Decision Tree for Key Comparisons

April 27, 2021

Author(s)

Antonio Possolo, Amanda Koepke, David Newton, Michael R. Winchester

This contribution describes a Decision Tree intended to guide the selection of statistical models and data reduction procedures in key comparisons (KCs). The

A new highly enriched 233U reference material for improved simultaneous determination of uranium amount and isotope amount ratios in trace level samples

January 26, 2021

Author(s)

Richard Essex, Ross W. Williams, Kayron T. Rogers, Cole R. Hexel, Tashi Parsons-Davis, Kerri C. Treinen

A highly-enriched 233U reference material (>0.99987 n(233U)/n(U)) has been prepared and characterized for use as an isotope dilution mass spectrometry spike. An

Comparison of primary laser spectroscopy and mass spectrometry methods for measuring mass concentration of gaseous elemental mercury

December 10, 2020

Author(s)

Abneesh Srivastava, Stephen E. Long, James E. Norris, Colleen E. Bryan Sallee, Jennifer Carney, Joseph Hodges

We present a direct comparison between two independent methods for the measurement of gaseous elemental mercury (GEM) mass concentration: isotope dilution cold

Modeling Temperature Effects on a Coriolis Mass Flowmeter

September 2, 2020

Author(s)

Fabio O. Costa, Jodie Gail Pope, Keith A. Gillis

Coriolis mass flowmeters are known to be stable, have low uncertainty (± 0.1 %), and are insensitive to fluid properties. This meter type is used for many

Tools and 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