U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 27326 - 27350 of 74035

Fundamental constants and tests of theory in Rydberg states of hydrogenlike ions

July 1, 2009
Author(s)
Ulrich D. Jentschura, Peter Mohr, Joseph N. Tan, Benedikt J. Wundt
A comparison of precision frequency measurements to quantum electrodynamic (QED) theoretical predictions can be used to test theory and to obtain information regarding fundamental constants. We find that for Rydberg states, theoretical uncertainties due to

Magnetocorrosion Of Pipeline Steel

July 1, 2009
Author(s)
Angelique N. Lasseigne
The effects of magnetocorrosion, altered corrosion behavior in the presence of magnetic fields, are described for pipeline steels. Changes in corrosion behavior, including pitting, cracking, and hydrogen ingress, were assessed with and without an applied

Middleware and Metrology for the Pervasive Future

July 1, 2009
Author(s)
Antoine Fillinger, Imad Hamchi, Stephane Degre, Lukas L. Diduch, Richard T. Rose, Jonathan G. Fiscus, Vincent M. Stanford
Using data streams from acoustic, video, proximity, location, and even physiological sensors, to recognize user intent and respond appropriately is one of the grand challenges to the multimodal research community. We describe our sensor-net middleware, the

Sensitivities and Variances for Fitted Parameters of Spheres

July 1, 2009
Author(s)
Christoph J. Witzgall, Marek Franaszek
Experimental data have been gathered by applying 3D imaging systems, such as LIDAR/LADAR instruments, to spherical objects. This report provides a compilation of the statistical and analytical procedures to be used for an evaluation, to be reported

Supplementary Backward Equations v(p, T) for the Critical and Supercritical Regions (Region 3) of the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam

July 1, 2009
Author(s)
H J. Kretzschmar, Allan H. Harvey, K Knobloch, Radim Mares, Kiyoshi Miyagawa, N Okita, Roland Span, I. Stocker, Wolfgang Wagner, I Weber
When steam power cycles are modeled, thermodynamic properties as functions of pressure and temperature are required in the critical and supercritical regions (region 3 of IAPWS-IF97). With IAPWS-IF97, such calculations require cumbersome iterative

The 2008 NCSLi Josephson Voltage Standards Interlaboratory Comparison

July 1, 2009
Author(s)
Harold V. Parks, William B. Miller, Leonard P. Pardo, Curtis Kiser, Clark A. Hamilton, Yi-hua D. Tang, Barry M. Wood
Josephson voltage standards (JVS) provide a highly accurate representation of the volt. Although the Josephson Effect provides an intrinsic standard of voltage, inter-comparisons between different systems are important to insure that potential sources of

Uncertainty Analysis of a Simple Fringe Projection System

July 1, 2009
Author(s)
Shawn P. Moylan, Gregory W. Vogl
Fringe projection is an optical method of measuring the surface profile of a part. Most basic fringe projection processes require an initial calibration step to determine components of coordinate transformation matrices before the surface point coordinates

Improved Isotopic Analysis With a Large Array of Gamma-Ray Microcalorimeters

June 30, 2009
Author(s)
Nikhil Jethava, Joel N. Ullom, Douglas A. Bennett, William B. Doriese, James A. Beall, Gene C. Hilton, Robert D. Horansky, Kent D. Irwin, Eric Sassi, Leila R. Vale, Minesh K. Bacrania, Andrew Hoover, P. J. Karpius, Michael W. Rabin, Clifford R. Rudy, Duc T. Vo
We present results from the largest array of gamma-ray microcalorimeters operated to date. The microcalorimeters consist of Mo/Cu transition-edge sensors with attached Sn absorbers. The detector array contains 66 pixels each with an active area 2.25 mm 2

Improved Isotopic Analysis with a Large Array of Gamma-ray Microcalorimeters

June 30, 2009
Author(s)
Nikhil Jethava, Joel N. Ullom, Douglas A. Bennett, William B. Doriese, James A. Beall, Gene C. Hilton, Robert D. Horansky, Kent D. Irwin, Eric Sassi
We present results from the largest array of gamma-ray microcalorimeters operated to date. The microcalorimeters consist of Mo/Cu transition-edge sensors with attached Sn absorbers. The detector array contains 66 pixels each with an active area 2.25 mm2

Laboratory Recognition Process for Project 25 Compliance Assessment

June 30, 2009
Author(s)
Kurt Fischer, Andrew P. Thiessen
Project 25 (P25) is a standards development process for the design, manufacture and evaluation of interoperable digital two-way wireless communications products created by and for public safety professionals. The published P25 standards suite is

Robots to the Rescue

June 30, 2009
Author(s)
Elena R. Messina
Despite current limitations, robots can still play a significant role in helping the response community by being their eyes and ears in dangerous, unknown, or difficult-to-access locations. This article describes how the National Institute of Standards and

Low Noise Amplification of a Continuous Variable Quantum State

June 29, 2009
Author(s)
Raphael C. Pooser, Alberto M. Marino, Vincent Boyer, Kevin M. Jones, Paul D. Lett
We present an experimental realization of a low-noise, universal, phase-insensitive optical amplifier using four-wave mixing interaction in hot Rb vapor. Performance near the quantum limit for a range of amplifier gains, including near unity, can be

A Multi-site Assessment of Precision and Reproducibility of Multiple Reaction Monitoring-based Measurements: Toward Quantitative Protein Biomarker Verification in Human Plasma

June 28, 2009
Author(s)
Nathan G. Dodder, Terri Addona, Susan Abbatiello, Birgit Schilling, Steven Skates, D.R. Mani, David M. Bunk, Clifford Spiegelman, Lisa Zimmerman, Amy-Joan Ham, Hasmik Keshishian, Steven Hall, Simon Allen, Ronald Blackman, Christoph Borchers, Charles Buck, Helene Cardasis, Michael Cusack, Bradford Gibson, Jason Held, Tara Hiltke, Angela Jackson, Eric Johansen, Christopher Kinsinger, Jing Li, Mehdi Mesri, Thomas Neubert, Richard Niles, Trenton Pulsipher, Henry Rodriguez, Paul A. Rudnick, Derek Smith, David Tabb, Tony Tegeler, Henry Variyath, Lorenzo Vega-Montoto, Asa Wahlander, Sofia Waldemarson, Mu Wang, Jeffrey Whitaker, Lei Zhao, N. Leigh Anderson, Susan Fisher, Daniel Liebler, Amanda Paulovich, Fred Regnier, Paul Tempst, Steven Carr
Candidate-based biomarker verification relies upon specific, quantitative assays optimized for selective detection of target proteins, and is increasingly viewed as a critical step in the biomarker discovery pipeline that bridges unbiased discovery to pre

Diagnostics and Optimization of a Miniature High Frequency Pulse Tube Cryocooler

June 28, 2009
Author(s)
Isaac Garaway, Alexander Veprik, Ray Radebaugh
A miniature, high energy density, Pulse Tube cryocooler has been developed, tested, diagnosed and optimized to provide appropriate cooling for size-limited cryogenic applications demanding fast cool down. This cryocooler, originally designed using REGEN 3

Investigation of Flow Nonuniformities in a Large 50 K Pulse Tube Cryocooler

June 28, 2009
Author(s)
Michael A. Lewis, Ryan P. Taylor, Ray Radebaugh, Isaac Garaway, Peter E. Bradley
A single stage pulse tube cryocooler was optimized to provide 50 W of net refrigeration power at 50 K when driven by a pressure oscillator that can produce up to 2.8 kW of acoustic power at 60 Hz. The cryocooler was designed with the ability to provide

Optimization Calculations for a 30 HZ, 4 K Regenerator with Helium-3 Working Fluid

June 28, 2009
Author(s)
Ray Radebaugh, Yonghua Huang, Agnes A. O'Gallagher, John M. Gary
The NIST numerical software, REGEN3.3, which incorporates both He-4 and He-3 properties, was used to calculate the losses and second law efficiencies of 4 K regenerators operating at 30 Hz. Operating parameters, such as average pressure, pressure ratio
Displaying 27326 - 27350 of 74035