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Test weight per bushel is a measurement of the weight of a volume of grain required to fill level full a Winchester bushel measure of 2,150.42 cubic inches in capacity , which is equivalent to 32 quarts. Test weight per bushel is one of the measurements
Iosif I. Shinder, Christopher J. Crowley, Bernard J. Filla, Michael R. Moldover
We discuss five significant improvements to the Air Speed Calibration Service conducted by the National Institute of Standards and Technology (NIST): 1. Reduced-uncertainty calibrations of the secondary standard [Laser Doppler Anemometer, (LDA)] using a
NIST and other laboratories calibrate meters that measure the flow of valuable liquids such as petroleum products. Historically, these calibrations have been conducted using Stoddard solvent. Laboratories using Stoddard solvent for liquid-flow calibrations
Karl G. Linden, Harold B. Wright, Sara E. Beck, Thomas M. Hargy, Thomas C. Larason, Randi M. McCuin
The use of bioassays to determine reduction equivalent doses delivered by UV reactors is recognized as an effective measure of UV disinfection systems. Low pressure (LP) UV delivered in controlled collimated beam systems provides dose response curves which
Thomas C. Larason, Keith R. Lykke, Ping-Shine Shaw, Lin Chungsan
Ultraviolet (UV) radiation effectively inactivates common pathogens found in ground and surface waters such as Cryptosporidium, Giardia, and most bacterial pathogens (e.g. E. coli). Water treatment facilities are now using UV radiation for disinfection of
George P. Eppeldauer, Howard W. Yoon, Dean G. Jarrett, Thomas C. Larason
For photocurrent measurements with low uncertainties, wide-dynamic range reference current-to-voltage converters and a new converter calibration method have been developed at the National Institute of Standards and Technology (NIST). The high feedback
Fernando L. Podio, Dylan J. Yaga, Christofer J. McGinnis
The latest version of the ANSI/NIST-ITL standard was published in November 2011 (AN-2011). In addition to specifying Record Types in traditional encoding, the standard includes the specification of National Information Exchange Model (NIEM) Extensible
Wei Chu, Robert M. Thompson, Jun-Feng Song, Theodore V. Vorburger
The consecutive matching striae (CMS) numeric criteria for firearm and toolmark identifications have been widely accepted by forensic examiners, although there have been questions concerning its observer subjectivity and limited statistical support. In
We evaluate a method for testing the radius of spheres with a hologram that consists of a pair of nested Fresnel zone lenses. The hologram is positioned in the collimated test beam of a Fizeau interferometer. The inner zone lens generates a focus at the
The vast majority of points collected with coordinate measuring machines are not used in isolation; rather, collections of these points are associated with geometric features through fitting routines. In manufacturing applications, there are two
An instrument that allows the simultaneous measurement of the mechanical deformation and Raman spectra of materials under contact loading is described. The instrument consists of a custom nanoindenter that operates on a laser-scanning Raman microscope.
Jun-Feng Song, Thomas B. Renegar, Johannes A. Soons, Balasubramanian Muralikrishnan, John S. Villarrubia, Xiaoyu A. Zheng, Theodore V. Vorburger
For the calibration of rectangular and trapezoidal profile roughness specimens, stylus tip will increase profile peak width and decrease valley width, which may cause the Ra changes (either increase or decrease, depends on the profile shape). Sometimes the
This interim report summarizes research results to date under the FY2012 interagency agreement between CPSC and NIST to develop testing and measurement protocols for determining the quantities and properties of nanoparticles released from flooring finishes
Expanding on earlier viscosity measurements of rocket propellants from 293 K to 373 K at atmospheric pressure, the viscosity of rocket propellant RP-2 was measured from 270 K to 450 K with pressures to 137 MPa. The instrument was an oscillating piston
Stephane Solve, Alain Rufenacht, Charles J. Burroughs, Samuel Benz
Two NIST Programmable Josephson Voltage Standard (PJVS) systems have been directly compared at 10V using different nanovoltmeters at the temperature of the laboratory. These PJVS systems use arrays double-stacked superconducting-niobium Josephson junctions
Hong Lin, Keith A. Gillis, XiaoJuan Feng, Michael R. Moldover, J.P. Sun, J.T. Zhang, Y.Y. Duan
We report improvements to our previous [Zhang et al., Intl. J. Thermophysics, 32, 1297 (2011)] determination of the Boltzmann constant kB using a single 80 mm-long cylindrical cavity. In this work, the shape of the gas-filled resonant cavity is closer to
Lee J. Gorny, Keith A. Gillis, Michael R. Moldover
As a part of NISTs program to standardize measurements of greenhouse gas emissions, we are developing long-wavelength acoustic flowmeter (LWAF) for accurate, economical measurement of flue gas flows, for example, from coal-burning power plants. A LWAF is
This publication contains Good Measurement Procedures (GMP), Good Laboratory Procedures (GLP), and Standard Operating Procedures (SOP) for use in calibration laboratories performing volumetric calibrations. This edition is updated from the 2012 version
ACT-Touch is a set of manual motor request extensions for ACT-R 6 (Adaptive Control of Thought-Rational, hereafter, ACT-R) . These manual request extensions constitute theoretical claims predicting motor preparation and execution times for certain manual
Jin Chu Wu, Michael W. Halter, Raghu N. Kacker, John T. Elliott, Anne L. Plant
Cell image segmentation is a part of quantitative studies regarding cell movement and cell behavior, and it plays a critical role in molecular biology and cellular biochemistry. Therefore, it is fundamentally important to evaluate the performance levels of
De-Hao D. Tsai, Frank W. DelRio, John M. Pettibone, Pin A. Lin, Jiaojie Tan, Michael R. Zachariah, Vincent A. Hackley
In this study, an electrospray-differential mobility analyzer (ES-DMA) was operated with an aerosol flow-mode, temperature-programmed approach to enhance its ability to characterize the particle size distributions (PSDs) of nanoscale particles (NPs) in the
The TSOM method provides three-dimensional nanoscale metrology using a conventional optical microscope. Substantial improvements in defect detectability using the TSOM method will be presented. The TSOM method shows potential to (i) detect phase defects on
David L. Duewer, Katherine E. Sharpless, Jeanice M. Brown Thomas, Sam A. Margolis
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes