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Srivalli Telikepalli, Dean C. Ripple, Kurt D. Benkstein, Kristen L. Steffens, Michael J. Carrier, Christopher B. Montgomery
Numerous particle sizing and counting methods exist for measuring particles in the submicrometer, subvisible, and visible size range. This article will briefly describe some key aspects that need to be considered for the most commonly used methods in order
Measurements of the relative permittivity (dielectric constant) of fluids such as methane have been interpreted with the assumption that the substance has zero dipole moment. This assumption is not strictly true, due to the presence of isotopologues with
Tina Butcher, Gloria Lee, Juana Williams, Breyanna M. Blackwell
NIST Handbook 44 was first published in 1949, having been preceded by similar handbooks of various designations and in several forms, beginning in 1918. NIST Handbook 44 is published in its entirety each year following the Annual Meeting of the National
We present here a summary of a workshop held 1-3 May 2018 at the National Physical Laboratory, Teddington, UK in which the focus was how the national metrology institutes of the world might help to address challenges in reproducibility of research. The
Marcus H. Mendenhall, Lawrence T. Hudson, Csilla I. Szabo-Foster, Albert Henins, James P. Cline
Abstract We present newly measured spectra of the X-ray emission of a molybdenum metal anode subject to electron bombardment, using a very high dispersion silicon double-crystal spectrometer. The measurement includes the dipole-allowed KL, KM, and KN
Robert D. Horansky, Jason B. Coder, John M. Ladbury
The Defense Information Systems Agency (DISA) Defense Spectrum Organization (DSO) throughthe Spectrum Sharing Test and Development (SSTD) program proposed a National AdvancedSpectrum and Communications Test Network (NASCTN) measurement campaign to
Scanning electron microscopy (SEM) is a practical tool to determine the dimensions of nanometer-scale features. Conventional width measurements use arbitrary criteria, e.g., a 50 % threshold crossing, to assign feature boundaries in the measured SEM
Greta Dalle Luche, Susan Bengston Nash, John Kucklick, Fletcher M. Mingramm, Ashley Russell
Marine mammal blubber is known to have quantifiable concentrations of steroid hormones and is increasingly chosen as a matrix for the detection of these reproductive and stress biomarkers. Steroid hormones act through complex cascades, often in concert
Barbara J. Belzer, Kari K. Harper, Titilayo O. Shodiya
NIST Handbook 150-2, 2019 edition, presents the technical requirements and guidance for the accreditation of laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP) Calibration Laboratories Program. The 2019 edition of NIST
This chapter describes the use of diffraction-based methods to characterize amorphous or disordered heterogeneous materials. Quantitative materials microstructure characterization using small-angle scattering methods is emphasized. While these techniques
Hany Assasa, Joerg Widmer, Tanguy Ropitault, Nada T. Golmie
Next generation wireless local area networks are envisioned to serve a high number of devices with heterogeneous capabilities and service requirements. Millimeter-wave technology is expected to be able to satisfy these demands and complement the highly
This publication contains standard operating procedures for calibrations that were not previously published in other NIST Office of Weights and Measures publications and are included here in support of weights and measures laboratory program requirements
Li Piin Sung, James E. Pickett, Olga Kuvshinnikova, Brett Ermi
Samples of polycarbonate (PC), poly(butylene terephthalate) (PBT), a PC/PBT blend, and poly(styrene-co-acrylonitrile) (SAN), all containing 3 % TiO2 (by mass), were exposed in the NIST (National Institutes of Standards and Technology) SPHERE (Simulated
Karoly Szipka, Andreas Archenti, Gregory W. Vogl, Alkan Donmez
The accuracy of multi-axis machine tools is affected to a large extent by the behaviour of the system's axes and their error sources. In this paper, a novel methodology using circular inertial measurements quantifies changes in squareness between two axes
Justin M. Zook, Jennifer H. McDaniel, Marc L. Salit, Nathanael D. Olson, Justin M. Wagner
Benchmark small variant calls are required for developing, optimizing and assessing the performance of sequencing and bioinformatics methods. Here, as part of the Genome in a Bottle (GIAB) Consortium, we apply a reproducible, cloud-based pipeline to
Zachary H. Levine, Adele P. Peskin, Edward J. Garboczi, Andrew Holmgren
Using a commercial X-ray tomography instrument, we have obtained reconstructions of a graded-index optical fiber with voxels of edge length 1.05 µm at 12 tube voltages. The fiber manufacturer created a graded index in the central region by varying the
This article describes electron energy-loss spectroscopy (EELS), energy-filtering transmission electron microscopy (EFTEM) and electron spectroscopic diffraction (ESD) in a transmission electron microscope (TEM) or in a scanning transmission electron
Angela C. Stelson, Minghui Lu, Charles A. Little, Christian J. Long, Nathan D. Orloff, Nicolas Stephanopolous, James C. Booth
Detection of conformational changes in biomolecular assemblies provides critical information into biological and self-assembly processes. State-of-the-art in situ conformation detection techniques rely on fluorescent labels or protein-specific binding