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Displaying 21126 - 21150 of 73830

Preparation of Non-equilibrium Nuclear Spin States in Double Quantum Dots

July 15, 2013
Author(s)
Jacob M. Taylor, Michael Gullans, Jacob J. Krich, Bertrand I. Halperin, M D. Lukin
We theoretically study the dynamic polarization of lattice nuclear spins in GaAs double quantum dots containing two electrons. We introduce a semiclassical model that allows to explore a wide range of parameter regimes in this system. We identify three

Use of Half Metallic Heusler Alloys in CoFeB/MgO/Heusler Alloy Tunnel Junctions

July 15, 2013
Author(s)
Andrew P. Chen, Gen G. Feng, Robert D. Shull
Heusler Alloys Co(sub2)FeSi and Co(sub2)MnSi were deposited on both single crystal MgO (100) and polycrystalline SiO(Sub2) silicon thermal oxide substrates and characterized by x-ray diffraction before and after thermal annealing at various temperatures

Picometer metrology for precise measurement of refractive index, pressure, and temperature

July 14, 2013
Author(s)
Jack A. Stone Jr., Patrick F. Egan, Jay H. Hendricks, Gregory F. Strouse, Douglas A. Olson, Jacob E. Ricker, Gregory E. Scace
For several years we have been studying the use of Fabry-Perot interferometers for precise measurement of the refractive index of gasses, where the primary motivation has been to improve interferometer-based length measurement. Because the refractive index

THE EFFECT OF MICROSTRUCTURE ON THE HYDROGEN-ASSISTED FATIGUE OF PIPELINE STEELS

July 14, 2013
Author(s)
Andrew J. Slifka, Elizabeth S. Drexler, Robert L. Amaro, Damian S. Lauria, April Stevenson, Douglas G. Stalheim, Louis E. Hayden
Tests on the fatigue crack growth rate were conducted on four pipeline steels, two of grade API 5L- X52 and two API 5L-X70. One X52 material was from the mid 1960s and the other was manufactured in 2011. The two X70 materials had a similar vintage and

Thermoelectric imaging of structural disorder in epitaxial graphene

July 14, 2013
Author(s)
Sanghee Cho, Stephen D. Kang, Wondong Kim, Eui-Sup Lee, Sung-Jae Woo, Ki-Jeong Kong, Ilyou Kim, Hyeong-Do Kim, Tong Zhang, Joseph A. Stroscio, Yong-Hyun Kim, Ho-Ki Lyeo
Many structural defects and strain fields develop during the preparation of thin films and nanostructures, with their origins being at the atomic level1,2. Sensitively detecting these subtle features with high sensitivity and resolution, and their

Anisotropic LMN dielectronic resonances from ratios of magnetic-dipole lines

July 13, 2013
Author(s)
Yuri Ralchenko, John D. Gillaspy
Signatures of multi-keV LMN dielectronic resonances in highly-charged 3dn ions of tungsten were detected in the intensity ratios of extreme-ultraviolet magnetic-dipole lines within ground configurations. The measurements were performed with an electron

RECON -- A Controlled English for Business Rules

July 13, 2013
Author(s)
Fabian M. Neuhaus, Edward J. Barkmeyer Jr.
Capturing business rules in a formal logic representation supports the enterprise in two important ways: it enables the evaluation of logs and audit records for conformance to, or violation of, the rules; and it enables the conforming automation of some

The Metrology of Counting Protein Particles

July 13, 2013
Author(s)
Dean C. Ripple, Michael J. Carrier, Richard E. Cavicchi, Christopher B. Montgomery, Zhishang Hu
A common degradation pathway for protein-based drugs is the growth of protein aggregates or particles. Counting and characterization of these particles is needed to assure the quality, efficacy, and safety of this type of drug. The unusual physical

Initial ACT-R Extensions for User Modeling in the Mobile Touchscreen Domain

July 12, 2013
Author(s)
Kristen Greene, Franklin Tamborello
Advances in mobile touchscreen computing offer new opportunities to test traditional cognitive architectures and modeling tools in a novel task domain. ACT-Touch, an extension of the ACT-R 6 (Adaptive Control of Thought- Rational) cognitive architecture

Molecular Layer-by-Layer Assembled Reverse Osmosis Membranes for Water Desalination

July 12, 2013
Author(s)
Joung-Eun Gu, Seunghye Lee, Wansuk Choi, Jong Suk Lee, Bo-Young Kim, Edwin Chan, Christopher Stafford, Jun-Young Chung, Joona Bang, Jung-Hyun Lee
Here, we report on the successful design, construction, and performance of membranes constructed using the mLbL process and show that these membranes exceed the performance of membranes synthesized through conventional interfacial polymerization. In our

Structure stability and electronic transport of gold nanowires on BeO (0001) surface

July 12, 2013
Author(s)
Shmuel Barzilai, Francesca M. Tavazza, Lyle E. Levine
Gold nanowire chains are considered a good candidate for nanoelectronics devices since they exhibit remarkable structural and electrical properties. For practical engineering devices, -wurtzite BeO may be a useful platform for supporting these nanowires

Superposition, Entanglement, and Raising Schroedinger's Cat

July 12, 2013
Author(s)
David J. Wineland
This is a written version of the lecture I presented in connection with the Nobel Prize ceremonies in December 2012. The paper briefly summarizes experiments on quantum state manipulaiton and measurement in the context of trapped atomic ions. The focus of

Atomic data for beam-stimulated plasma spectroscopy in fusion plasmas

July 11, 2013
Author(s)
O. Marchuk, Yuri Ralchenko, David R. Schultz, W. Biel, T. Schlummer, TEXTOR Team
Injection of high energy atoms into a confined plasma volume is an established diagnostic technique in fusion research. This method strongly depends on the quality of atomic data for charge exchange spectroscopy (CXRS), motional Stark effect (MSE) and beam

Atomic Data for Iron-group Elements of Astrophysical Interest

July 11, 2013
Author(s)
Gillian Nave, Craig J. Sansonetti, J C. Pickering, Matthew Ruffoni, Anne P. Thorne, Florence Liggins
The joint project between NIST and Imperial College London to measure spectra of singly-ionized iron-group elements using Fourier transform and high-resolution grating spectroscopy is described.

Biometric Specifications for Personal Identity Verification

July 11, 2013
Author(s)
Patrick J. Grother, Wayne J. Salamon, Ramaswamy Chandramouli
Homeland Security Presidential Directive HSPD-12, Policy for a Common Identification Standard for Federal Employees and Contractors [HSPD-12], called for new standards to be adopted governing interoperable use of identity credentials to allow physical and

IREX IV: Part 1, Evaluation of Iris Identification Algorithms

July 11, 2013
Author(s)
George W. Quinn, Patrick J. Grother, Mei L. Ngan, James R. Matey
IREX IV aims to provide a fair and balanced scientific evaluation of the performance of automated iris recognition algorithms. IREX IV evaluated the performance of 66 identification (i.e. one-to-many matching) algorithms submitted by 12 companies and

IREX VI - Temporal Stability of Iris Recognition Accuracy

July 11, 2013
Author(s)
Patrick J. Grother, James R. Matey, Elham Tabassi, George W. Quinn, Michael Chumakov
Background: Stability is a required definitional property for a biometric to be useful. Quantitative statements of stability are operationally important as they dictate re-enrollment schedules e.g. of a face on a passport. Ophthalmologists consider the

Multi-resonant plasmonic nanodome arrays for label-free biosensing applications

July 10, 2013
Author(s)
Charles J. Choi, Stephen Semancik
The characteristics and utility of plasmonic nanodome arrays capable of supporting multiple resonance modes are described. A low-cost, large-area replica molding process is used to produce, on flexible plastic substrates, two-dimensional periodic arrays of

On the bending strength of single-crystal silicon theta-like specimens

July 10, 2013
Author(s)
Rebecca R. Kirkpatrick, William Alexander Osborn, Michael S. Gaither, Richard S. Gates, Frank W. DelRio, Robert F. Cook
A new theta geometry was developed for micro-scale bending strength measurements. The new "gap" theta specimen was a simple modification of the arch theta specimen that enabled micro-scale tensile testing. The gap theta was demonstrated here on single

Toward a reference architecture for archival systems

July 10, 2013
Author(s)
Raphael Barbau, Joshua Lubell, Sudarsan Rachuri, Sebti Foufou
Long-term preservation of product data is imperative for many organizations. A product data archive should be designed to ensure information accessibility and understanding over time. Approaches such as the Open Archival Information System (OAIS) Reference
Displaying 21126 - 21150 of 73830
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