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Displaying 2726 - 2750 of 2934

Continuum of Quantum Fluctuations in a Three-Dimensional S = 1 Heisenberg Magnet

January 1, 2019
Author(s)
K. W. Plumb, Hitesh J. Changlani, A. Scheie, Shu Zhang, J. W. Krizan, Jose Rodriguez Rivera, Yiming Qiu, B. Winn, R. J. Cava, Collin L. Broholm
Spin liquids are a fundamentally new phase of matter that cannot be described by a broken symmetry and have no order parameter. While the quantum entanglement that characterizes a quantum spin liquid is not directly accessible to any current measurement

Atomic clock performance beyond Earths gravitational limit

December 6, 2018
Author(s)
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Stefan A. Schaeffer, Kyle P. Beloy, Daniele Nicolodi, Roger C. Brown, N. Hinkley, G. Milani, Marco Schioppo, T. H. Yoon, Andrew D. Ludlow
The passage of time is tracked by counting oscillations of a suitable frequency reference (e.g., the number of revolutions of Earth around the sun or the number of swings of a pendulum of a grandfather clock). By referencing the oscillations arising from

Guidance for Evaluating Contactless Fingerprint Acquisition Devices

July 27, 2018
Author(s)
John M. Libert, John D. Grantham, Bruce Bandini, Stephen S. Wood, Michael D. Garris, Kenneth Ko, Frederick R. Byers, Craig I. Watson
This document details efforts undertaken by the National Institute of Standards and Technology (NIST) to develop measurements and a protocol for the evaluation of contactless (touchless) fingerprint acquisition devices. Contactless fingerprint capture

Estimating Error Rates for Firearm Evidence Identifications in Forensic Science

March 1, 2018
Author(s)
Jun-Feng Song, Theodore V. Vorburger, Wei Chu, James H. Yen, Johannes A. Soons, D Ott, Nien F. Zhang
Estimating error rates for firearm evidence identification is a fundamental challenge in forensic science. This paper describes the recently developed Congruent Matching Cells (CMC) method for image comparisons, its application to firearm identification

Rheological Measurement of Suspensions Without Slippage: Experimental and Model

December 13, 2016
Author(s)
Alex Olivas, Michelle A. Helsel, Nicos Martys, Chiara C. Ferraris, William L. George, Raissa Ferron
The conclusion of international studies was that the optimal approach to calibrate concrete rheometers would be to develop a non-Newtonian standard reference material (SRM) that contained inclusions similar in size to aggregates used commonly in concrete

Scalable Manufacturing of Layer-by-Layer Membranes for Water Purification

December 1, 2016
Author(s)
Christopher M. Stafford
Water is critical to the health and security of our nation. And as our population expands and water scarcity becomes a reality, we as a people need to think creatively on how we safeguard access to clean water. The manufacturing of today’s state-of-the-art

Electrical Units in the New SI: Saying Goodbye to the 1990 Values

May 12, 2016
Author(s)
Nick Fletcher, Gert Rietveld, James K. Olthoff, Ilya F. Budovsky
The proposed redefinition of several SI base units is a topic that has been on the metrology agenda for the last decade. The general principles and the motivation for the changes have been presented at the NCSLI several times. However, recent progress on

Dimensional Reduction of Duplex DNA Under Nanofluidic Slit Confinement

August 19, 2015
Author(s)
Luis Fernando Vargas Lara, Jack F. Douglas, Samuel M. Stavis, Elizabeth A. Strychalski, Jon C. Geist, Brian J. Nablo
There has been much recent interest in the dimensional properties of duplex DNA under nanoscale confinement conditions as a problem of fundamental interest in both technological and biological fields. This has led to a series of measurements by

Longitudinal Study of Fingerprint Recognition

June 30, 2015
Author(s)
Soweon Yoon, Anil Jain
Human identification by fingerprints is based on the fundamental premise that ridge patterns from distinct fingers are different (uniqueness) and a fingerprint pattern does not change over time (persistence). While the uniqueness of fingerprints has been

High-dimensional hyperentanglement of mode-locked two-photon states

June 29, 2015
Author(s)
Zhenda Xie, Tian Zhong, Sajan Shrestha, XinAn Xu, Junlin Liang, Yan-Xiao Gong, Alessandro Restelli, Jeffrey Shapiro, Franco N. Wong, Chee Wei Wong, Joshua Bienfang
Quantum entanglement is the fundamental resource for quantum information processing and communications, including secure data rates with higher capacities and better error resilience [1-9]. In dense-coded quantum communication channels, it is desirable to

Dual-microcavity narrow-linewidth Brillouin laser

March 5, 2015
Author(s)
William Loh, Adam A. Green, Frederick N. Baynes, Daniel C. Cole, Franklyn J. Quinlan, Hansuek Lee, Kerry J. Vahala, Scott A. Diddams
The tunable narrow-linewidth laser is a revolutionary metrology tool that is critical in precision spectroscopy and the determination of fundamental physical constants, displacement measurements at the 10 -20 level, and the development of the most advanced

Applicability of post-ionization theory to laser-assisted field evaporation of magnetite

December 18, 2014
Author(s)
Ann C. Chiaramonti Debay, D. K. Schreiber, Lyle M. Gordon, Karen Kruska
Analysis of the mean Fe ion charge state from laser-assisted field evaporation of magnetite (Fe3O4) reveals unexpected trends as a function of laser pulse energy that break from conventional post-ionization theory for metals. For Fe ions evaporated from

ENVIRONMENTAL METABOLOMICS: NMR TECHNIQUES

December 8, 2013
Author(s)
Myrna Simpson, Dan Bearden
Environmental metabolomics is a rapidly growing area of research, and over the last decade the focus has been on organism responses to various types of environmental stressors (pollutants, nutritional shifts, and global climate change, for example)

Evaluating Fire Blocking Performance of Barrier Fabrics

October 15, 2013
Author(s)
Shonali Nazare, William M. Pitts, Shaun M. Flynn, John R. Shields, Rick D. Davis
The purpose of fire blocking barrier materials is to reduce the flammability of soft furnishings ( mattresses and upholstered furniture) by preventing or delaying direct flame impingement from open flames and/or heat transfer from smoldering ignition
Displaying 2726 - 2750 of 2934
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