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Displaying 126 - 150 of 2593

Models for an Ultraviolet-C Research and Development Consortium

March 25, 2022
Author(s)
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

The Irradiance Instrument Subsystem (IRIS) on the Airborne-Lunar Spectral Irradiance (Air-LUSI) Instrument

March 23, 2022
Author(s)
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

Uncertainty estimation for 2D magnetic particle imaging

March 21, 2022
Author(s)
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

Versailles Project on Advanced Materials and Standards (VAMAS) Interlaboratory Study on Measuring the Number Concentration of colloidal gold nanoparticles

March 9, 2022
Author(s)
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

ZKASP: ZKP-based Attestation of Software Possession for Measuring Instruments

March 9, 2022
Author(s)
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

Negative quasiprobabilities enhance phase estimation in quantum-optics experiment

March 1, 2022
Author(s)
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

Toward a New Primary Standardization of Radionuclide Massic Activity Using Microcalorimetry and Quantitative Milligram-Scale Samples

February 24, 2022
Author(s)
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

KEY COMPARISON - Instrumented Charpy tests on low- and high-energy specimens

February 18, 2022
Author(s)
Enrico Lucon, Renato Reis Machado
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

Characterizing Frequency Stability Measurements having Multiple Data Gaps

February 2, 2022
Author(s)
David A. Howe, Noah Schlossberger
Time series measurements with data gaps (dead times) prevent accurate computations of frequency variances such as the Allan variance (AVAR) and its square-root ADEV. To extract frequency distributions, data must be sequentially ordered and equally spaced

New reference materials for trace-levels of actinide elements in plutonium

January 27, 2022
Author(s)
Richard Essex, Lav Tandon, Amy Gaffney, Cole Hexel, Debbie Bostick, Lisa Colletti, Diana Decker, Casey Finstad, Joseph Giaquinito, Elmer Lujan, John Partridge, Benjamin Roach, John Rolinson, Kyle Samperton, Alice Slemmons, Khalil Spencer, Floyd Stanley, Lisa Townsend, Kerri Treinen, Ross Williams, Christopher Worley
Two plutonium oxides were prepared as unique reference materials for actinides occurring as trace constituents in Pu. Each reference material unit is approximately 200 mg of PuO2 in a quartz glass vial. Characterized attributes of the oxides included mass

Quantitative Determination of Cell Viability Using Absorbance Microscopy

January 19, 2022
Author(s)
Greta Babakhanova, Stephen Zimmerman, Laura Pierce, Sumona Sarkar, Nicholas Schaub, Carl Simon Jr.
Cell viability is an essential measurement for cell therapy products. One of the most common tests is Trypan blue (TB) dye exclusion where blue-stained cells are counted via imaging. Typically, live and dead cells are counted based on pixel intensities of

AbsorbanceQ: An App for Generating Absorbance Images from Brightfield Images

January 4, 2022
Author(s)
Stephen Zimmerman, Carl Simon Jr., Greta Babakhanova
The AbsorbanceQ app converts brightfield microscope images into absorbance images that can be analyzed and compared across different operators, microscopes and time. Absorbance-based measurements are comparable, which is useful when the aim is to
Displaying 126 - 150 of 2593