Search Publications

Displaying 201 - 225 of 1513

PLANAR METAMATERIAL ABSORBERS FOR CALIBRATION OF MICROWAVE RADIOMETERS FOR ATMOSPHERIC REMOTE SENSING

July 22, 2022

Author(s)

Omar Khatib, Dazhen Gu, Jonah Smith, William Deal, Willie Padilla, Steven Reising

In this work, we present metamaterial-based microwave absorbers fabricated on organic-based printed circuit boards as promising alternatives to traditional, bulky microwave absorbers for the calibration of microwave radiometers for atmospheric remote

Analyzing the NIST Charpy Program Database: Influence of Impact Hammer Type (C vs. U) on Test Results

July 20, 2022

Author(s)

Enrico Lucon, Raymond L. Santoyo

The NIST Charpy Machine Verification Program supplies ASTM E23 certified Charpy reference specimens to customers all over the world since 1989, when the program was transferred from the US Army at Watertown Arsenal, Massachusetts. Starting in 1993

Tensile Tests at 77 K and 4 K on 316L Stainless Steel Welded Plates

July 19, 2022

Author(s)

Dash Weeks, Nicholas Derimow, Jake Benzing

Based on the collaborative framework established between ASME, NASA, and NIST, quasi-static tensile tests were performed in liquid nitrogen (77 K) and liquid helium (4 K) on tensile specimens extracted from the centers of four welded 316L stainless steel

The Expanding Role of National Metrology Institutes in the Quantum Era

July 12, 2022

Author(s)

Alexander Tzalenchuk, Nicolas Spethmann, Tim Prior, Jay H. Hendricks, Yijie Pan, Vladimir Bubanja, Guilherme Temporao, Dai-Hyuk Yu, Damir Ilic, Barbara L. Goldstein

Now that all base units are defined in terms of fundamental constants and can thus — at least in principle — be realized anytime and anywhere, rather than through a measurement chain leading back to unique physical artefacts, who holds the traceability

The need for multicomponent gas standards for breath biomarker analysis

July 7, 2022

Author(s)

Kavita Jeerage, Jennifer Berry, Jacolin Murray, Cassie Goodman, Paulina Piotrowski, Christina Jones, Christina Cecelski, Jennifer Carney, Katrice Lippa, Tara Lovestead

Exhaled breath is a non-invasive, information-rich matrix with the potential to diagnose or monitor disease, including infectious disease. Despite significant effort dedicated to biomarker identification in case control studies, very few breath tests are

Reference Correlation for the Viscosity of Difluoromethane (R-32) from the Triple Point to 425 K and up to 70 MPa

July 4, 2022

Author(s)

Danai Velliadou, Konstantinos Antoniadis, Marc Assael, Marcia L. Huber

We present a new wide-ranging correlation expressed in terms of temperature and density for the viscosity of difluoromethane (R-32) based on critically evaluated experimental data. The correlation is designed to be used with an existing equation of state

The Effect of Increased Strength and Stiffness Requirements on the Functional Recovery Performance of Reinforced Concrete Special Moment Frames

July 1, 2022

Author(s)

Dustin Cook, Siamak Sattar

Given the recent focus on recovery-based design, this study examines the effect of increased design strength and stiffness requirements on the functional recovery performance for a set of eight reinforced concrete moment frame archetypes. Each archetype is

Report of the 105th & 106th National Conference on Weights and Measures

June 30, 2022

Author(s)

Shelby Bowers, Yvonne Branden, Tina G. Butcher, Richard A. Harshman, Gloria Diane Lee, David Sefcik, Lisa Warfield

The 105th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held virtually July 12 - 16, 2020. The 106th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 18 - 23, 2021, at the Hyatt Regency

An International Standard Formulation for trans-1-Chloro-3,3,3-trifluoroprop-1-ene [R1233zd(E)] Covering Temperatures from the Triple-point Temperature to 450 K and Pressures up to 100 MPa

June 25, 2022

Author(s)

Ryo Akasaka, Eric W. Lemmon

A new Helmholtz energy equation of state is presented for trans-1-chloro-3,3,3-trifluoroprop-1-ene [R1233zd(E)], which is expressed with temperature and density as the independent variables. Experimental data in the range of temperatures from 215 K to 444

The NIST REFPROP database for highly accurate properties of industrially important fluids

June 21, 2022

Author(s)

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

Spreadsheet-Based Software for the Analysis of Homogeneous and Inhomogeneous Data Sets in Accordance with ASTM E1921-21

June 14, 2022

Author(s)

Enrico Lucon

NIST has developed a user-friendly spreadsheet-based software package for the Master Curve analysis of fracture toughness tests performed in the ductile-to-brittle transition region and the determination of the reference temperature To, in accordance with

An International Standard Formulation for 2,3,3,3-Tetra uoroprop-1-ene (R1234yf) Covering Temperatures from the Triple-point Temperature to 410 K and Pressures up to 100 MPa

June 13, 2022

Author(s)

Eric W. Lemmon, Ryo Akasaka

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

Physical model for multi-point normalization of dual-inlet isotope ratio mass spectrometry data

June 1, 2022

Author(s)

Abneesh Srivastava

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