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Polette Centellas, Stian Romberg, Ran Tao, Alexander Landauer, Karl Schoch, Huong Giang Nguyen, Gale Holmes, Gery Stafford, Christopher Soles
Residual stresses inevitably develop in thermosetting materials used for semiconductor packaging during the curing process and in service. Understanding the development of these deleterious stresses is necessary for improving predictive models and
Temperature changes affect the coercivity of permanent magnets, thereby impacting the $Bl$ factor and potentially introducing systematic errors in Kibble balance measurements. While the thermal-magnetic effect is negligible in large magnet systems, it
Complex chalcogenides in the MPS3 family of materials (M = Mn, Fe, Co, and Ni) display remarkably different phase progressions depending upon the metal center orbital filling, character of the P–P linkage, and size of the van der Waals gap. There is also a
Evan Groopman, Todd Williamson, Timothy Pope, Michael Bronikowski, Spencer M. Scott, Matthew Wellons
We present important aspects of uranium particle age dating by Large-Geometry Secondary Ion Mass Spectrometry (LG-SIMS) that can introduce bias and increase model age uncertainties, especially for small, young, and/or low-enriched particles. This metrology
Oluwagbemiga Ojo, Wilarachchige D. C. B. Gunatilleke, Winnie Wong-Ng, Tieyan Chang, Yu-Sheng Chen, Joshua Martin, Adam Biacchi, George Nolas
The 18R polytype of SnSe2 possesses unique structural features that can directly impact the transport properties and potential applications of interest; however, a comprehensive understanding of the intrinsic physical properties is lacking. We grew large
NIST is leading and supporting multiple efforts to develop standards for 3D imaging systems used for industrial automation. There are few standards for verifying the performance of these systems and NIST is working with ASTM subcommittee E57.23 on
Ashley Russell, Carolyn Burdette, Johanna Camara, Nathanael Heckert, Jennifer Hoguet, Kevin Huncik, Jared Ragland, Elena Wood
Standard Reference Material (SRM) 3672a Organic Contaminants in Smokers' Urine (Frozen) and SRM 3673a Organic Contaminants in Non-Smokers' Urine (Frozen) are intended for use in evaluating analytical methods for the determination of selected naturally
We conduct cw-Optically Detected Magnetic Resonance (ODMR) measurements using a fiber-coupled NV sensor to infer temperature. Our approach leverages a probabilistic feedforward inference model designed to maximize the likelihood of observed ODMR spectra
Srivalli Telikepalli, Dean Ripple, Michael Carrier, Kristen Steffens, David Newton, Christopher Montgomery, Nicholas Ritchie, Anthony Asmar, Michael Halter
Standard Reference Material (SRM) 1989 is a NIST particle standard produced using photolithographic methods and delivers a certified value for particle size of an irregularly shaped particle. This SRM was developed to allow a more accurate monitoring of
Peter Mohr, David Newell, Barry N. Taylor, Eite Tiesinga
We report the 2022 self-consistent values of constants and conversion factors of physics and chemistry recommended by the Committee on Data of the International Science Council (CODATA). The recommended values can also be found at physics.nist.gov
Andrea Yarberry, Charles Barber, Laura Wood, Walter Wilson
NIST launched a Cannabis Laboratory Quality Assurance Program (CannaQAP) in 2020 to assist laboratories in demonstrating and improving cannabis (hemp and marijuana) measurement comparability and competence. CannaQAP provided tools that allowed analysts and
3D stereo depth sensors have a variety of applications, including sensing for autonomous vehicles, reverse engineering, and manufacturing automation. The performance of these sensors can be affected by various factors, such as sensor construction, sensor
3D stereo depth sensors have a variety of applications, including sensing for autonomous vehicles, reverse engineering, and manufacturing automation. The performance of these sensors can be affected by various factors, such as sensor construction, sensor
David La Mantia, Mingxin Lei, Nikunjkumar Prajapati, Noah Schlossberger, Matthew Simons, Christopher Holloway, Julia Scherschligt, Stephen Eckel, Eric Norrgard
We demonstrate a blackbody radiation thermometer based on optically excited rubidium atoms in a vapor cell. Operating as a calibrated contact thermometer from 308K to 343 K, we realize temperature uncertainty as low as 0.04 %, and statistical temperature
Veruska Malave, Newell Moser, Edward Garboczi, Mark McLinden, Jason Widegren, Christopher Suiter
Our earlier work demonstrated that nuclear magnetic resonance (NMR) spectroscopy is a viable technique for in situ analysis of vapor–liquid equilibria (VLE) of fluid mixtures and that inserting a capillary into the NMR sample tube allows the simultaneous
David Deisenroth, Jordan Weaver, Sergey Mekhontsev, Steven Grantham, Shawn P. Moylan
One of key parameters of additive manufacturing by laser powder bed fusion of metal parts (PBF-LB/M) is the power density distribution (PDD) of the process laser beam. This paper describes the methods used to measure the beam PDD, discussing well
Balasubramanian Muralikrishnan, Katharine Shilling, Vincent Lee, Olga Ridzel, Glenn Holland, John Villarrubia
We describe a method to calibrate angular positioning errors of a rotation stage using a laser tracker (LT), a plane mirror mounted on the stage, and stationary registration nests placed around the stage. Our technique involves determining the direction of
Patrick McArdle, Bradley Pelz, Christopher Yung, Nathan Tomlin, John Lehman, Michelle Stephens
In this work we describe the use of a THz quantum cascade laser (QCL) to perform bi-directional reflectance distribution (BRDF) measurements. In particular we are interested in the reflectance properties of ultra-black absorbers for use in detector devices
Through the teaching of the International System of Units (SI) principles, Science, Technology, Engineering, and Mathematics (STEM) educators create a ripple effect, cultivating the next generation of metrologists. This, in turn, builds the solid
Sara Rostampour, Song-Syun Jhang, Jung Kai Hsu, Rachel Cook, Yuejin Li, chunlei fan, Li Piin Sung
Microplastics pose a significant environmental threat, and understanding their sources and generation mechanisms is crucial for mitigation efforts. This study investigates the effects of ultraviolet intensity, temperature, and relative humidity on the
Sina Ghadi, Xiaobo Chen, Nicholas Tomasello, Nicholas Derimow, Srikanth Rangarajan, Guangwen Zhou, Scott Schiffres
Assessment of metal powders in powder bed additive manufacturing is crucial, as the quality of the powders significantly impacts the final printed parts. This study introduces a novel technique to characterize metal powders by analyzing changes in their
Michael Link, Megan Claflin, Christina Cecelski, Ayomide Akande, Delany Kilgour, Paul Heine, Matthew Coggon, Chelsea Stockwell, Andrew Jensen, Jie Yu, Han Huyhn, Jenna Ditto, Carnsten Warneke, William Dresser, Keighan Gemmell, Spiro Jorga, Rileigh Robertson, Joost de Gouw, Timothy Bertram, Jonathan Abbatt, Nadine Borduas-Dedekind, Dustin Poppendieck
Proton-transfer-reaction mass spectrometry (PTR-MS) using hydronium ion (H3O+) ionization is widely used for the measurement of volatile organic compounds (VOCs) both indoors and outdoors. H3O+ ionization, as well as the associated chemistry in an ion
Abstract In this study, two-phase heat transfer characteristics of cryogenic two-phase nitrogen were investigated. This basic information is required for the sequential design of a mixed refrigerant micro-cryocooler. The effective heat exchanger must be
Creating a reliable indicator to describe the degradation of ball screws remains a challenging task. Current vibration-based prognostic methods are vulnerable to unknown noise or system disturbances. To address this challenge, our study offers a new method
Perception systems for autonomous vehicles (AVs) require various types of sensors, including light detection and ranging (LiDAR), cameras, and radars, to ensure their robustness in driving scenarios and weather conditions. The data from these sensors are