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Displaying 31376 - 31400 of 74047

Model, Prediction and Experimental Verification of Composition and Thickness in Continuous Spread Thin Film Combinatorial Libraries Grown by Pulsed Laser Deposition

July 16, 2007
Author(s)
Nabil Bassim, Peter K. Schenck, Makoto Otani, Hiroyuki Oguchi
Pulsed laser deposition (PLD) is a powerful technique for growing continuous spread thin film libraries of continuously varying composition as a function of position on a substrate. Continuous spread thin film libraries are grown by striking a ceramic

MODELING AND EXPERIMENTS ON FAST COOLDOWN OF A 120 Hz PULSE TUBE CRYOCOOLER

July 16, 2007
Author(s)
Srinivas Vanapalli, Michael A. Lewis, Gershon Grossman, Zhihua Gan, Ray Radebaugh, H.J. M. ter Brake
High frequency operation of a pulse tube cryocooler leads to reduced regenerator volume, which results in a reduced heat capacity and a faster cooldown time. A pulse tube cryocooler operating at a frequency of 120 Hz and an average pressure of 3.5 MPa

A Virtual Rapid Chloride Permeability Test

July 15, 2007
Author(s)
Dale P. Bentz
The rapid chloride permeability test (RCPT), as it is commonly called, has been in existence for over 20 years and was standardized by ASTM over 15 years ago. The test is used extensively in the concrete industry for assessing concrete quality and is now

Analysis of Welding Parameter Distribution in Stud Arc Welding

July 15, 2007
Author(s)
Ivan Samardzic, Stefanija Klaric, Thomas A. Siewert
This paper describes the application of on-line monitoring system for recording welding current and voltage during stud arc welding with a ceramic ferrule. Recorded values of welding current and voltage are analyzed off-line for the weld process with both

ILThermo: A Free-Access Web Database for Thermodynamic Properties of Ionic Liquids

July 15, 2007
Author(s)
Qian Dong, Chris D. Muzny, Andrei F. Kazakov, Vladimir Diky, Joe W. Magee, Jason A. Widegren, Robert D. Chirico, Kenneth N. Marsh, Michael D. Frenkel
The development, scope, and functionality of the web-based ionic liquids database, ILThermo, are described. The database is available free to the public, and aims to provide users worldwide with up-to-date information from publications of experimental

RoHS Harmonization - Progress Toward a Single Global Standard?

July 13, 2007
Author(s)
Eric D. Simmon
The lack of global harmonization of RoHS initiatives has been a major headache for the electronics industry, to say the least. A number of organizations have been working very diligently to move standards closer together, with the hope that at some point

Scattering and Interference in Epitaxial Graphene

July 13, 2007
Author(s)
Gregory M. Rutter, Jason Crain, T Li, P First, Joseph A. Stroscio
A single sheet of carbon, graphene, exhibits unexpected electronic properties that arise from quantum state symmetries, which restrict the scattering of its charge carriers. Understanding the role of defects in the transport properties of graphene is

Color Rendering

July 11, 2007
Author(s)
Yoshihiro Ohno
LED technologies are advancing at a swift pace and solid-state lighting (SSL) products are already introduced to the market and expected to grow rapidly. There is an increasing interest and concern in the color rendering properties of white SSL products

Measurement of Solid-State-Lighting Products

July 11, 2007
Author(s)
Yoshihiro Ohno, Carl C. Miller
This paper discusses issues of photometric measurements of solid-state-lighting (SSL) products, for quantities including luminous flux, luminous efficacy, luminous intensity distribution, and color characteristics. Standards for SSL products are urgently

Measuring the Luminance of a Retroreflective Sign

July 11, 2007
Author(s)
Carl C. Miller, T Heimer, Tim Donahue, M Schwartz, David Kuniega
The area of retroreflective signage for traffic control is moving from fixed retroreflective requirements to a traffic scenario/performance based system. CIE Technical Report 54.2, Retroreflection: Definition and Measurement , published in 2001, offers

New Photometer Standards for Low Uncertainty Illuminance Scale Realization

July 11, 2007
Author(s)
George P. Eppeldauer, Carl C. Miller, Yoshihiro Ohno
Improved performance photometers have been developed at the National Institute of Standards and Technology (NIST) to utilize the low spectral responsivity uncertainty of spectral irradiance responsivity measurements performed on the facility of Spectral

Pilot Study on Daytime Color Appearance of Retroreflective Sheeting

July 11, 2007
Author(s)
Wendy L. Davis, Carl C. Miller, Jason Kennedy, Carl Andersen
In this experiment, reference instrument measurements of the chromaticity of retroreflective materials were compared with human visual perceptions of their colors under daytime conditions. A hue scaling method was used to measure perceived color. Four

Subwavelength Addressibility and Spin-Dependent Transport in a Double-Well Optical Lattice

July 11, 2007
Author(s)
Patricia J. Lee, M Anderlini, Ben L. Brown, Jennifer Sebby-Strabley, William D. Phillips, James V. Porto
We report the experimental demonstration of site-selective RF addressing of atoms with sub-wavelength resolution in a spin-dependent optical lattice of double wells. We also show spin-dependent transport: coherent spatial separation of atomic wave packets

Synthetic Incoherence for Electron Microscopy

July 11, 2007
Author(s)
Zachary H. Levine, Robyn M. Dunstan
Tomographic studies of submicrometer samples in materials science using electron microscopy have been inhibited by diffraction effects. In the present work, we describe two practical methods for ameliorating these effects. In one, the sample is scanned

Microfluidic Dynamic Light Scattering Used for High Throughput Measurements

July 10, 2007
Author(s)
Thomas Q. Chastek, Kathryn L. Beers, Eric J. Amis
When diluted in some solvents, surfactants and block copolymers self-assemble into micelles or vesicles of about 10-100 nm in size. There is a great deal of interest in micelles and vesicles because they are widely used in the formulations industry, and
Displaying 31376 - 31400 of 74047