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Marcia L. Huber, Eric W. Lemmon, Ian Bell, Mark O. McLinden
The NIST REFPROP database is a powerful tool for calculating thermophysical properties of industrially important fluids, and this manuscript describes the models implemented in, and features of, this database. REFPROP implements the most accurate models
Stephan Schlamminger, Leon Chao, Vincent Lee, David B. Newell, Clive Speake
The torsion pendulum at the heart of the BIPM apparatus to measure the gravitational constant, $G$, is used to measure the gravitational torque between source and test-mass assemblies with two methods. In the Cavendish method, the pendulum moves freely. In
Solomon I. Woods, Jorge Neira, James E. Proctor, Joseph P. Rice, Nathan Tomlin, Malcolm White, Michelle Stephens, John H. Lehman
We have developed generalized methods for electrical substitution optical measurements, as well as cryogenic detectors which can be used to implement them. The new methods enable measurement of arbitrary periodic waveforms by an electrical substitution
A new fundamental equation of state is presented for 2,3,3,3-tetra uoroprop-1-ene (R1234yf). The equation is valid from the triple point temperature (121.6 K) to 410 K at pressures up to 100 MPa, where typical expanded uncertainties (k = 2) in calculated
Zane Comden, Stephan Schlamminger, Charles Waduwarage Perera, Frank Seifert, David B. Newell, Jay H. Hendricks, Barbara L. Goldstein, Leon Chao
After the 2019 redefinition of the International System of Units (SI), torque no longer needs to be traceable to a calibrated weight suspended from a known lever arm. Specifically, a modification of the Kibble principle used for realizing the kilogram
A simple model is presented for multi-point normalization of dual-inlet isotope ratio mass spectrometry (DI-IRMS) data. The model incorporates the scale contraction coefficient and the normalized working reference gas isotope delta value as its two
There is a pressing need for reliable, reproducible and accurate measurements of graphene's properties. To facilitate industrial growth, several documentary measurement standards are under development within the Nanotechnologies committees of both ISO 229
Tom Parker, Victor Zhang, Jian Yao, Gerard Petit, Roger Brown, James Hanssen
A three-cornered hat analysis has been performed on three independent time transfer systems between the United States Naval Observatory (USNO) and the National Institute of Standards and Technology (NIST). These include (1) a direct Two-Way Satellite Time
Elijah Petersen, Richard Uhl, Blaza Toman, John Elliott, John Gordon
Background: The Electrophilic Allergen Screening Assay (EASA) has emerged as a promising method for risk and hazard assessment for skin sensitization classification. This assay functions by assessing the depletion of one of two probe molecules (4
Single-photon detection via absorption in current-biased nanoscale superconducting structures has become a preferred technology in quantum optics and related fields. Single-mode fiber packaged devices have seen new records set in detection efficiency
One function that tissue phantoms for fluorescence guided imaging (FGI) systems are fabricated for, is to track an imaging system's repeatability and reproducibility performance as a light detector. This can be made more universally useful if the optical
Improvements in a lamp-monochromator-based facility at the National Institute of Standards and Technology (NIST), the Visible near-infrared Spectral Comparator Facility (VisSCF) which is used to calibrate optical detectors for spectral radiant power
Dianne L. Poster, Matthew Hardwick, C Cameron Miller, Michael A. Riley, W. W. Shanaka I. Rodrigo, Andras E. Vladar, John D. Wright, Christopher D. Zangmeister, Clarence Zarobila, Jeremy Starkweather, John Wynne, Jason Yilzarde
Data for interpreting virus inactivation on N95 face filtering respirators (FFRs) by ultraviolet (UV) radiation are important in developing UV strategies for N95 FFR disinfection and reuse for any situation, whether it be everyday practices, contingency
Paul Heyliger, Clemens Junker, Karsten Meier, Ward L. Johnson
Vibrational modes of unrestrained elastic cylinders of trigonal crystals are studied using Ritz-based polynomial approximations for displacements formulated in rectangular Cartesian coordinates. The selected orientation of the threefold trigonal axis is
Dianne L. Poster, C Cameron Miller, Yaw S. Obeng, John J. Kasianowicz, Michael T. Postek, Norman Horn, Troy Cowan, Richard Martinello
The development of an international, precompetitive, collaborative, ultraviolet (UV) research consortium is discussed as an opportunity to lay the groundwork for a new UV commercial industry and the supply chain to support this industry. History has
Steven Grantham, Thomas C. Larason, Clarence Zarobila, Stephen Maxwell, John Woodward, Kevin Turpie, S. Andrew Gadsden
The objective of the airborne LUnar Spectral Irradiance (air-LUSI) project is to make low uncertainty, SI-traceable measurements of the lunar spectral irradiance in the visible to near-infrared (VNIR) region from an aircraft above most of the optically
Mark-Alexander Henn, Klaus Natorf Quelhas, Solomon I. Woods
Magnetic Particle Imaging (MPI) has in recent years been established as a powerful imaging tool that measures thenon-linear magnetic response of magnetic particles to an applied field. Obtaining quantitative information fromthese images in the form of a
Caterina Minelli, Karen E. Murphy, Monique Johnson, Antonio Montoro Bustos, Jeffrey Fagan, Ingo Strenge
We describe the outcome of an international interlaboratory study of the measurement of particle number concentration of colloidal nanoparticles, project 10 of the technical working area 34, "Nanoparticle Populations" of the Versailles Project on Advanced
Luis Brandao, Carlos Eduardo Cardoso Galhardo, Rene Peralta
Software-controlled measuring instruments used in commercial transactions, such as fuel dispensers and smart meters, are sometimes subject to "memory replacement" attacks. Cybercriminals replace the approved software by a malicious one that then tampers
Noah Lupu-Gladstein, Y. Batuhan Yilmaz, David Arvidsson-Shukur, Aharon Brodutch, Arthur Pang, Aephraim Steinberg, Nicole Halpern
Operator noncommutation, a hallmark of quantum theory, limits measurement precision, according to uncertainty principles. Wielded correctly, though, noncommutation can boost precision. A recent foundational result relates a metrological advantage with
Robert A. Fletcher, James J. Filliben, Nicholas Ritchie
Standard Reference Material (SRM) 2806: Medium Test Dust in Hydraulic Fluid represents a series of reference materials certified by the National Institute of Standards and Technology (NIST) used to calibrate liquid-borne optical (or automatic) particle
Ryan P. Fitzgerald, Bradley Alpert, Dan Becker, Denis E. Bergeron, Richard Essex, Kelsey Morgan, Svetlana Nour, Galen O'Neil, Dan Schmidt, Gordon A. Shaw, Daniel Swetz, R. Michael Verkouteren, Daikang Yan
We present a new paradigm for the primary standardization of radionuclide activity per mass of solution (Bq/g). Two key enabling capabilities are 4π decay-energy spectrometry using chip-scale sub-Kelvin microcalorimeters and direct realization of mass by
This report describes a CIPM Key Comparison through the SIM/MWG-7 organization, concerning instrumented impact testing of low-energy (20 J) and high-energy (100 J) Charpy V-notch specimens. In this Comparison, various instrumented and non-instrumented data