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NIST Authors in Bold

Displaying 2976 - 3000 of 74160

2023 OWM Annual Analysis

July 6, 2023
Author(s)
John McGuire, Lisa Warfield
The NIST OWM Analysis is submitted to assist the Weights and Measures community as it deliberates on items before the Conference. NIST OWM offers these comments and recommendations based upon information and input available as of the date of this report.

A Data-Driven Approach to Complex Voxel Predictions in Grayscale Digital Light Processing Additive Manufacturing Using U-nets and Generative Adversarial Networks

July 6, 2023
Author(s)
Jason Killgore, Thomas Kolibaba, Benjamin Caplins, Callie Higgins, Jake Rezac
Machine learning models such as U-nets like the pix2pix conditional generative adversarial network (cGAN) are shown to predict 3D printed voxel geometry in digital light processing (DLP) additive manufacturing. The models are trained on microscopic voxel

Concentration of Ignitable Liquid Residue from Simulated Fire Debris by Dynamic Vapor Microextraction: Sensitivity to Instrument Settings and Debris Characteristics

July 6, 2023
Author(s)
Jennifer Berry, Mary Gregg, Amanda Koepke, Reta Newman, Kavita Jeerage
Dynamic vapor microextraction (DVME) is a potential method for the extraction and concentration of ignitable liquid (IL) residue in fire debris. This low flow rate, purge-and-trap headspace concentration method collects IL vapors onto a chilled adsorbent

Cylindrical Acoustic Gas Thermometry

July 6, 2023
Author(s)
Li Xing, X.J. Feng, Ming-Hao Si, Jintao Zhang, Hong Lin, Keith Gillis, Michael Moldover
We review recent determinations of the Boltzmann constant kB and the differences T-T90 that used cylindrical acoustic gas thermometry (c-AGT). These determinations measured the acoustic resonances frequencies of argon gas enclosed by metal-walled

Physical Models and Dimensional Traceability of 2.4 mm Coaxial Airline Standards for Determining Systematic Uncertainties of Calibrated Scattering-Parameters

July 6, 2023
Author(s)
Jeffrey Jargon, Dylan Williams, Angela Stelson, Chris Long, Aaron Hagerstrom, John R. Stoup, Eric S. Stanfield
In this report, we document the models and dimensional traceability of our 2.4 mm coaxial airline standards for performing multiline thru-reflect-line calibrations up to 50 GHz using vector network analyzers. We identify the equations used in our models of

Characterization of Die-Swell in Thermoplastic Material Extrusion

July 5, 2023
Author(s)
Austin Colon, David Kazmer, Amy Peterson, Jonathan Seppala
Die-swell is a flow effect that occurs in polymer extrusion whereby the material experiences rapid stress and dimensional changes upon exiting the nozzle orifice. Material extrusion additive manufacturing is no exception, and this effect influences the

Enhancement of Optical Absorption by Oxygen Plasma Treatment in Carbon Nanotube-based Black Paint Coating

July 5, 2023
Author(s)
Atasi Dan, Joel Rutkowski, Patrick McArdle, Erica Freire Antunes, Nathan Tomlin, Malcolm White, Michelle Stephens, John H. Lehman
Effect of oxygen (O2) plasma treatment on reflectance properties and surface morphology of CNT-based paint was investigated. We demonstrate a specular reflectance less than 0.10% and hemispherical reflectance less than 2.5% throughout the UV-Vis-NIR range.

High-resolution Melt Pool Thermal Imaging for Metals Additive Manufacturing Using the Two-color Method with a Single Color Camera

July 5, 2023
Author(s)
Alexander Myers, Guadalupe Quirarte, Francis Ogoke, Brandon Lane, Syed Uddin, Amir Barati Farimani, Jack Beuth, Jonathan Malen
We introduce an experimental method to image melt pool temperature with a single commercial color camera and compare the results with multi-physics computational fluid dynamic (CFD) models. This approach leverages the principle of two-color (i.e

Investigating the Cut-off Effect of n-alcohols on Lipid Movement: A Biophysical Study

July 5, 2023
Author(s)
Michael H. Nguyen, Dominik Dziura, Mitchell DiPasquale, Stuart R. Castillo, Elizabeth Kelley, Drew Marquardt
Cellular membranes are responsible for absorbing the effects of external perturbants for the cell's survival. Such perturbants include small ubiquitous molecules like n-alcohols which were observed to exhibit anesthetic capabilities, with this effect

Steady Melting in Material Extrusion Additive Manufacturing

July 5, 2023
Author(s)
Austin Colon, David Kazmer, Amy Peterson, Jonathan Seppala
Purpose One of the main causes of defects within material extrusion additive manufacturing is the non-isothermal condition in the hot end, which leads to inconsistent extrusion and weld healing. This work validates a custom hot end design intended to melt

Wideband Cyclostationary Spectrum Analysis for Smart Factory Wireless Channels

July 5, 2023
Author(s)
Peter Vouras, Mohamed Hany, Rick Candell
Smart and highly automated factories rely on time sensitive networks (TSNs) to coordinate the actions of robots working together to complete a task. The dense layout of metallic objects on the factory floor creates a complex electromagnetic environment

Analyzing Cybersecurity Definitions for Non-experts

July 4, 2023
Author(s)
Lorenzo Neil, Julie Haney, Kerrianne Buchanan
There is no standard definition for cybersecurity, with current definitions often being technically-complex and targeted at practitioners and academics. However, non-experts (those who do not have security expertise) need an understandable definition to

H2 Generation by the 10B(n,alpha)7Li Reaction in High Temperature Water

July 4, 2023
Author(s)
Alan Keith Thompson, Mohamad Al-Sheikhly, Steven Guerin, David Bartels, Cameron Goodwin, Sangho Nam
H2 produced in water from the 10B(n,α)7Li fission reaction has been measured up to 300 oC. Thermal energy neutrons from the Rhode Island Nuclear Science Center's 2 MW reactor interact with boric acid-containing water in temperature-controlled high-pressure

Influence of Fluorescent Dopants on the Vat Photopolymerization of Acrylate-based Plastic Scintillators

July 3, 2023
Author(s)
Thomas Kolibaba, Jason Killgore, Caleb Chandler, Dominique Porcincula, Michael Ford, Benjamin Fein-Ashley, Jason Brodsky, Alan Sellinger
Plastic scintillators, a class of solid-state materials used for radiation detection, were additively manufactured with vat photopolymerization. The photopolymer resins consisted of a primary dopant and a secondary dopant dissolved in a bisphenol A

Tests of Fundamental Physics

July 3, 2023
Author(s)
Eite Tiesinga, Peter Mohr
We describe recent developments in tests of quantum-electrodynamics (QED), the theory of the interactions of matter with electromagnetic fields. The tests focus on consistency in the determination of parameters or constants within QED obtained via multiple

Units and constants

July 3, 2023
Author(s)
Eite Tiesinga
We describe atomic and natural units relevant for the atomic, molecular, and optical physics described in this book. For nonrelativistic models of atoms and molecules absorbing and emitting photons atomic units are appropriate. That is energies and lengths

Quantum Disordered Ground State in the Triangular-Lattice Magnet NaRuO 2

July 1, 2023
Author(s)
Brenden R. Ortiz, Paul M. Sarte, Alon H. Avidor, Aurland Hay, Eric Kenney, Alexander I. Kolesnikov, Daniel M. Pajerowski, Adam A. Aczel, Keith M. Taddei, Craig Brown, Chennan Wang, Michael J. Graf, Ram Seshadri, Leon Balents, Stephen Wilson
The realization of spin liquid states born from the near-critical regime of the triangular lattice Hubbard model in inorganic materials remains a long-standing challenge, where weak spin-orbit coupling and other small perturbations often induce

Additive Manufacturing Data and Metadata Acquisition-General Practice

June 30, 2023
Author(s)
Yan Lu, Ho Yeung, Jason Fox, Felix Kim, Luke Mohr
Increasingly, a vast variety of additive manufacturing (AM) datasets are generated through AM development lifecycles. The amount, type, and speed of the collected data are unprecedented. The datasets are created and collected for material development

Additive Manufacturing Data Integration and Recommended Practice

June 30, 2023
Author(s)
Yan Lu, Milica Perisic, Albert T. Jones
Additive manufacturing (AM) creates parts layer by layer directly from three-dimensional computer-aided design data. Building in layers allows the fabrication of complex geometric shapes as well as functionally graded materials. Despite the part-quality

Effect of austenite fraction and stability on strength-hardening-ductility in additively manufactured 17-4 PH stainless steel containing nitrogen

June 30, 2023
Author(s)
Saadi Habib, Steven P. Mates, Fan Zhang, Mark R. Stoudt, James Zuback, Olaf Borkiewicz
Additively-manufactured (AM) 17-4 precipitation-hardening (PH) martensitic stainless steel (SS) built from nitrogen-atomized powder often retains a large volume fraction of austenite. The retained austenite lowers the yield strength compared to both
Displaying 2976 - 3000 of 74160
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