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Displaying 32201 - 32225 of 74178

Effective-Range Description of a Bose Gas Under Strong Confinement

January 29, 2007
Author(s)
Pascal Naidon, Eite Tiesinga, William F. Mitchell, Paul S. Julienne
We point out in this paper that previous theories describing s-wave collisions of atomic bosons confined in 1D or 2D geometries can be extended to much tighter confinements by simply replacing the scattering length by the effective energy-dependent

Chemical Twinning of the Pyrochlore Structure in the System Bi 2 O 3-Nb 2O 5

January 28, 2007
Author(s)
Ian E. Grey, W G. Mumme, Terrell A. Vanderah, Robert S. Roth, C Bougerol-Chaillout
New ternary bismuth iron niobates having structures based on chemical twinning of pyrochlore are described. Bi5.67Nb10FeO35 has hexagonal symmetry, P63/mmc, a = 7.432(1) , c = 31.881(2) , Z = 2 and Bi9.3Nb16.9Fe1.1O57.8 has rhombohedral symmetry, R-3m, a =

Pattern-directed to isotropic dewetting transition in polymer films on micropatterned surfaces with differential surface energy contrast

January 27, 2007
Author(s)
D Julthongpiput, Wenhua Zhang, Jack F. Douglas, Alamgir Karim, Michael J. Fasolka
Surface chemical patterns can both cause and direct dewetting in overlying thin films. However, a key factor in this behavior, the magnitude of surface energy differences between pattern domains ( ?g ), is largely unevaluated. To probe the effect of this

Contact Mechanics of Layered Elastic Materials: Experiment and Theory

January 26, 2007
Author(s)
P M. McGuiggan, Jay S. Wallace, Douglas T. Smith, I Sridhar, Z Zheng, K L. Johnson
This paper reports an experimental and theoretical investigation of the indentation of a layered elastic solid, with special reference to the surface force apparatus (SFA). The contacting surfaces of the SFA comprise a 3-layer material: a thin mica surface

Leakage Effects in Microwave Power Measurements

January 26, 2007
Author(s)
Ronald A. Ginley, Denis X. LeGolvan, Ann F. Monke
Because microwave power measurements are used to support almost every segment of the microwave electronics industry, the accuracy of these measurements is critical. Recently, we have several different problems that affect microwave power measurements which

Leakage Effects on Microwave Power Measurements

January 26, 2007
Author(s)
Ronald A. Ginley, Denis X. LeGolvan, Ann F. Monke
Microwave power measurements are used to support almost every every segment of the microwave electronics industry. It is very important for these measurements to be as accurate as possible. Recently we have found several different problems that affect

Light Force in Ultracold Photoassociation

January 26, 2007
Author(s)
Eduardo Gomez, A T. Black, Lincoln Turner, Eite Tiesinga, Paul D. Lett
We study the time-resolved photoassociation of ultracold sodium in an optical dipole trap. The photoassociation laser excites pairs of atoms to molecular states of large total angular momentum at high intensities (above 20 kW/cm2). Such transitions are

National Marine Analytical Quality Assurance Program:Results and Description of the NIST/NOAA 2005 Interlaboratory Comparison Exercise for Trace Elements in Marine Mammals

January 24, 2007
Author(s)
Steven J. Christopher, Rebecca S. Pugh, Michael B. Ellisor, Elizabeth A. Mackey, Rabia Oflaz, Barbara J. Porter, Kathie J. Bealer, John R. Kucklick, Paul R. Becker, T K. Rowles
NIST helps benchmark and improve the quality of analytical data gathered on the marine environment by administering annual interlaboratory comparison exercises through several programs, including the National Marine AnalyticalQuality Assurance Program

Optimal Quantum Measurements of Expectation Values of Observables

January 24, 2007
Author(s)
Emanuel Knill, Gerardo Ortiz, Rolando Somma
Experimental characterizations of a quantum system involve the measurement of expectation values of observables for a preparable state |f> of the quantum system. Such expectation values can be measured by repeatedly preparing |f> and coupling the system to

A High-Throughput Thermoelectric Power-Factor Screening Tool for Rapid Construction of Thermoelectric Property Diagrams

January 23, 2007
Author(s)
Makoto Otani, Nathan Lowhorn, Peter K. Schenck, Winnie K. Wong-Ng, Martin L. Green, K Itaka, H Koinuma
We have developed a high throughput screening tool that maps out thermoelectric power factors of combinatorial composition-spread film libraries. The screening tool allows us to measure the electrical conductivity and Seebeck coefficient of over 1000

TEM Horn Antenna Design Principles

January 23, 2007
Author(s)
Chriss A. Grosvenor, Robert T. Johnk, David R. Novotny, Nino Canales, Benjamin Davis, Jason Veneman
The National Institute of Standards and Technology has developed several ultra-wideband, TEM Horn antennas with phase linearity, short impulse duration, and a near constant antenna factor. These are time-domain antennas used to measure impulsive fields

DUC 2005: Evaluation of Question-Focused Summarization Systems

January 22, 2007
Author(s)
Hoa T. Dang
The Document Understanding Conference (DUC) 2005 evaluation had a single user-oriented, question-focused summarization task, which was to synthesize from a set of 25-50 documents a well-organized, fluent answer to a complex question. The evaluation shows

Dynamic Test Collections: Measuring Search Effectiveness on the Live Web

January 22, 2007
Author(s)
Ian M. Soboroff
Existing methods for measuring the quality of search algorithms use a static collection of documents. A set of queries and a mapping from the queries to the relevant documents allow the experimenter to see how well different search engines or engine

Influence of Oxygen Vacancies on the Dielectric Properties of Hafnia

January 22, 2007
Author(s)
Eric J. Cockayne
First-principles calculations were used to study the effects of neutral and 2+ charged oxygen vacancies on the dielectric properties of crystalline HfO2. In agreement with previous results, the neutral vacancy is more stable on the 4-fold coordinated site

Fluorescence Intermittency and Spectral Shifts of Single Bio-Conjugated Nanocrystals Studied by Single Molecule Confocal Fluorescence Microscopy and Spectroscopy

January 21, 2007
Author(s)
Hyeong G. Kang, Mathew Maye, Dmytro Nykypanchuk, Matthew L. Clarke, Peter Yim, J R. Krogmeier, Kimberly A. Briggman, Oleg Gang, Jeeseong Hwang
We have fabricated a combined measurement system capable of confocal microscopy and fluorescence spectroscopy to simultaneously evaluate multiple optical characteristics of single fluorescent nanocrystals. The single particle detection sensitivity is

Spherical Rubidium Vapor Cells Fabricated By Micro Glass Blowing

January 21, 2007
Author(s)
E. J. Eklund, A Shkel, Svenja A. Knappe, Elizabeth A. Donley, John E. Kitching
This paper presents an application of micro glass blowing, in which multiple glass spheres are simultaneously shaped on top of a silicon wafer and subsequently filled with rubidium. The fabrication process is based on etching cavities in silicon, followed

User's Guide to NIST Biometric Image Software (NBIS)

January 21, 2007
Author(s)
Kenneth Ko
This document (User's Guide to NIST Biometric Image Software (NBIS)) is renamed from the User's Guide to NIST Fingerprint Image Software (NFIS). In other word, this document is a replacement for the User's Guide to NIST Fingerprint Image software (NFIS)
Displaying 32201 - 32225 of 74178