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Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, Neal Craft, Fillmer Ruegg, Emil Schonberger, Robert Schaffer, Robert Paule
From 1984 to 2017, the National Institute of Standards and Technology coordinated the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat soluble vitamins and carotenoids in human serum and plasma. This report
Huong Giang T. Nguyen, Laura Espinal, Roger D. van Zee, Matthias Thommes, Blaza Toman, Sterlin Hudson, Enzo Mangano, Stefano Brandani, Katie Cychosz, Pieter Bertier, Feng Yang, Bernhard Krooss, Rebecca Siegelman, Jeffrey Long, Yoko Nakada, Kazu Nakai, Armin Ebner, James Ritter, Aaron Moran, Orhan Talu, Yi Huang, Krista Walton, Pierre Billemont, Guy de Weireld
This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess carbon dioxide adsorption isotherms on NIST Reference Material RM
This paper demonstrates a simple method to enhance visibility through clean-burning flames that allows new opportunities to perform optical metrology in fire research. The method combines narrow-spectrum, blue illumination and matched optical filters to
Thomas W. LeBrun, Peter Schuck, Wei Ren, Justine Yoon, Xianghui Dong, Nicole Y. Morgan, Jeffrey Fagan, Huaying Zhao
Analytical ultracentrifugation (AUC) is a first-principles based method for studying particles in solution by monitoring the evolution of their radial concentration distribution as a function of time in the presence of a high centrifugal field. In
Mattias Kruskopf, Jiuning Hu, Bi Y. Wu, Yanfei Yang, Hsin Y. Lee, Albert F. Rigosi, David B. Newell, Randolph E. Elmquist
We report the growth of large-area monolayer graphene on the centimeter scale using an optimized growth process allowing for reproducibility and morphology improvements. Magneto-transport measurements on graphene quantum Hall effect devices demonstrate the
Jiuning Hu, Mattias Kruskopf, Yanfei Yang, Bi Y. Wu, Jifa Tian, Alireza R. Panna, Albert F. Rigosi, Hsin Y. Lee, George R. Jones Jr., Marlin E. Kraft, Dean G. Jarrett, Kenji Watanabe, Takashi Taniguchi, Randolph E. Elmquist, David B. Newell
We report the fabrication and measurement of top gated epitaxial graphene p-n junctions where exfoliated hexgonal boron nitride (hBN) is used as the gate dielectric. The four terminal longitudinal resistance across a single junction is well quantized at R_
Alain Rufenacht, Nathan Flowers-Jacobs, Anna Fox, Steven B. Waltman, Robert E. Schwall, Paul Dresselhaus, Samuel P. Benz, Charles J. Burroughs
We present the first dc comparison of a programmable Josephson voltage standards and a pulse- driven Josephson arbitrary waveform synthesizer (JAWS) at 3 V. Both devices are mounted side- by-side on the cold stage of a cryocooler. The relative agreement
Alain Rufenacht, Charles J. Burroughs, Paul Dresselhaus, Samuel P. Benz
The voltage error associated with the leakage current of programmable Josephson voltage standards (PJVS) is one of the largest contributions to the uncertainty in direct comparison of voltage standards. Due to the parallel biasing scheme of the PJVS and
Nathan Flowers-Jacobs, Alain Rufenacht, Anna Fox, Steven B. Waltman, Justus Brevik, Paul Dresselhaus, Samuel P. Benz
This paper describes a new generation of Josephson Arbitrary Waveform Synthesizers which generate ac waveforms with a root-mean-squared (rms) amplitude of 3 V over a quantum-accurate operating range greater than 1 mA at 1 kHz. This system is composed of
Alain Rufenacht, Yi-hua D. Tang, Stephane Solve, Anna E. Fox, Paul D. Dresselhaus, Charles J. Burroughs, Robert E. Schwall, Regis Chayramy, Samuel P. Benz
We have performed direct dc comparisons between two cryocooled 10 V programmable Josephson voltage standards utilizing an automated synchronization scheme for the voltage reversals, which enables the use of a high-sensitivity analog null detector on its 10
Nicholas G. Paulter Jr., Donald R. Larson, Nicklaus F. Troje
The effect of motion through the portal of a walk-through metal detector (WTMD) has often been considered to contribute to the uncertainty in detecting threat objects being carried through the WTMD. However, typical metrological testing uses a robotic
Blunt trauma and brain injury can occur during impacts at energies and velocities below those observed in ballistic and blast events. During low to medium velocity impacts, the shell prevents helps to prevent bone fractures and the padding helps limit the
We calibrate (i.e., fit the parameters of) a seven-parameter single-diode model (SDM) for photovoltaic device performance using current-voltage (I-V) curves measured under controlled laboratory conditions over a matrix of temperature and nominal irradiance
Kumel H. Kagalwala, Elizabeth A. Goldschmidt, Sergey V. Polyakov, Alan L. Migdall
We report progress towards the implementation of a quantum memory in a rare-earth ion-doped crystal. Toward that goal, we demonstrate a narrowband spectral filter for our memory, and measure the optical correlations.
The set of software metrics introduced by Maurice H. Halstead in the 1970's has seen much scrutiny and not infrequent criticism. This article takes a fresh look at these metrics using quantity calculus (the algebra of units) and a new approach to
John R. Jendzurski, Nicholas G. Paulter Jr., Michael Harner, Ram Narayanan
It is common practice to use a metal conducting sphere for radar calibration purposes. The aspect-independence of a sphere allows for a more accurate and repeatable calibration of a radar than using a nonspherical calibration artifact. In addition, the
James A. Fedchak, Patrick J. Abbott, Jay H. Hendricks, Paul C. Arnold, Neil T. Peacock
This document represents a recommended practice for the calibration of ionization gauges using the comparison method. In this method, ionization gauges are compared to a working standard that has an SI traceable calibration. The ionization gauge is either
Anne L. Plant, Chandler A. Becker, Robert J. Hanisch, Ronald F. Boisvert, Antonio M. Possolo, John T. Elliott
The concepts and methods of measurement science can help provide clarity in the definition of reproducibility and its role in the scientific process. The qualities of rigorous research include reproducibility as one component, but there are other important
Ndubuisi G. Orji, Yaw S. Obeng, Carlos Beitia, Supika Mashiro, James Moyne
This white paper provides an overview of virtual metrology (VM) and the benefits it can provide, with cost reduction (both capital expenditure and cycle time) being the primary benefit. The white paper also examines some of the issues preventing wider
John Bowden, Candice Z. Ulmer, Christina M. Jones, Jeremy P. Koelmel, Richard A. Yost
Introduction Efforts to harmonize lipidomic methodologies have been limited within the community. Here, we aimed to capitalize on the recent NIST lipidomics interlaboratory comparison exercise by implementing a questionnaire that assessed current