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Displaying 951 - 975 of 2606

Diamond Sensors and Polycapillary Lenses for X-ray Absorption Spectroscopy

October 13, 2013
Author(s)
Bruce D. Ravel
Diamond sensors are evaluated as incident beam monitors for X-ray Absorption Spectroscopy experiments. These single crystal devices pose a challenge for an energyscanning experiment using hard X-rays due to the e ect of diffraction from the crystalline

Report of the Key Comparison CCPR-K5 Spectral Diffuse Reflectance

October 2, 2013
Author(s)
Yoshihiro Ohno, Maria E. Nadal, Kenneth L. Eckerle, E. A. Early
This is an official report from Consultative Committee of Photometry and Radiometry (CCPR) on the Key Comparison CCPR-K5 spectral diffuse reflectance, conducted in the framework of CIPM Mutual Recognition Arrangement (MRA). 13 national laboratories

Using a Laser Tracker to Actively Coordinate the Motion of a 3m Industrial Robot to Within 50 Microns: An ongoing effort to accurately determine and correct positioning errors.

October 1, 2013
Author(s)
David R. Novotny, Joshua A. Gordon, Jason B. Coder, Jeffrey R. Guerrieri, Michael H. Francis
We are using industrial-grade robotics guided by a metrology-grade laser tracker to perform antenna calibrations at mmWave frequencies. We are using a 3 m-reach robot to spherically scan a milli-meter Wave (mmWave) probe around an antenna under test (AUT)

Functional Constraints and the Design of a New Watt Balance

September 30, 2013
Author(s)
Leon S. Chao, Stephan Schlamminger, Jon R. Pratt
The functional constraints driving the design of the new permanent-magnet driven watt balance (NIST-4) outline the variables and compromises worthy of addressing. Construction according to these design parameters will demonstrate the high precision

Determining Reference Test Weight per Bushel Value of Grains

September 26, 2013
Author(s)
Gloria D. Lee
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

IMPROVEMENTS TO NIST'S AIR SPEED CALIBRATION SERVICE

September 24, 2013
Author(s)
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

Removing the Hydrocarbon Liquid from Hydrocarbon Liquid Flow Standards

September 24, 2013
Author(s)
Jodie G. Pope, Christopher J. Crowley
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

Measuring the UV Action Spectra of Pathogens and Surrogates

September 22, 2013
Author(s)
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

Using a Tunable Ultraviolet Laser for the Inactivation of Water Pathogens

September 22, 2013
Author(s)
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

Holographic Radius Test Plates

September 7, 2013
Author(s)
Quandou (. Wang, Johannes A. Soons, Ulf Griesmann
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 Effect of Tip Size in Calibration of Surface Roughness Specimens with Rectangular Profiles

September 2, 2013
Author(s)
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

Characterization of Airborne Nanoparticle Released from Consumer Products

August 29, 2013
Author(s)
Li Piin Sung, Joannie W. Chin, Andrew K. Persily
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

Wide Ranging Viscosity Measurements of Rocket Propellant RP-2

August 28, 2013
Author(s)
Arno D. Laesecke, Dylan S. Cousins
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

Direct Comparison of two NIST PJVS systems at 10 V

August 27, 2013
Author(s)
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
Displaying 951 - 975 of 2606