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Displaying 34626 - 34650 of 73832

Blackbody radiation shift of the 27 Al + 1 S 0 - 3 P 0 transition

March 27, 2006
Author(s)
Till P. Rosenband, Wayne M. Itano, Piet Schmidt, David Hume, Jeroen Koelemeij, James C. Bergquist, David J. Wineland
The differential polarizability, due to near-infrared light at 1126 nm, of the 27Al + 1S 0 – 3P 0 transition is measured to be {Δ}α = (1.6 ± x 10 -31 m 3, where {Δ}α = α P - α S is the difference between the excited and ground state polarizabilities. This

Dietary Supplement Standard Reference Materials

March 27, 2006
Author(s)
Lane C. Sander, Katherine E. Sharpless, Stephen A. Wise
A new category of Standard Reference Materials based on dietary supplements are under development by NIST, with certified values for organic constituents and selected trace elements. These materials are provided primarily for use in method development and

New Industry Requirements for Clock Synchronization and Time Stamping

March 27, 2006
Author(s)
Harvey Wohlwend, Ya-Shian Li-Baboud
This presentation will report on the results of an industry working group studying time synchronization. The working group will present new industry requirements as well as guidelines for improving time synchronization and time stamping. Efficient

Power Dependence of the Shift Caused by Spurious Spectral Components in Atomic Fountain

March 27, 2006
Author(s)
Filippo Levi, Jon H. Shirley, Thomas P. Heavner, Dai Yu, Steven R. Jefferts
In this paper we analyze the behavior of the frequency shift caused by spurious spectral component in the microwave spectrum against variation of the excitation microwave field. The theory of the shift caused by the presence of spurs in the microwave

Spectroscopy of neutral 174 Yb in a one-dimensional optical lattice

March 27, 2006
Author(s)
C Hoyt, Zeb Barber, Christopher W. Oates, A. V. Taichenachev, V. I. Yudin, Leo W. Hollberg
We report spectroscopy of the 1S 0 - 3P 0 clock transition in neutral 174Yb atoms confined to a one- dimensional optical lattice at the ac Stark shift-canceling wavelength of 759.35 nm. Spectroscopic linewidths as narrow as 4 Hz, full width at half-maximum

Failure of Glass Layers on Polymeric Substrates From Vickers Indentation

March 25, 2006
Author(s)
Herzl Chai, Brian R. Lawn
A study is made of median crack evolution in brittle coatings subjected to sharp contacts. A model bilayer system consisting of a glass plate bonded to a polycarbonate base, with a Vickers pyramid as indenter, is used to demonstrate the evolution in situ

Bias Reduction in Roughness Measurement through SEM Noise Removal

March 24, 2006
Author(s)
R Katz, C D. Chase, R Kris, R Peltinov, John S. Villarrubia, B Bunday
The importance of Critical Dimension (CD) roughness metrics such as Line and Contact edge roughness (LER, CER) and their associated width metrics (LWR, CWR) have been dealt with widely in the literature and are becoming semiconductor industry standards

Sub-micron gap capacitor for measurement of breakdown voltage in air

March 24, 2006
Author(s)
Emmanouel S. Hourdakis, Brian Simonds, Neil M. Zimmerman
We have developed a new method for measuring the value of breakdown voltage in air for electrode separations from 400 nm to 45 'm. The electrodes used were thin film Au lines evaporated on sapphire. The resulting capacitors had an area of 80 'm by 80 'm

Hyperspectral Image Projectors for Radiometric Applications

March 23, 2006
Author(s)
Joseph P. Rice, Steven W. Brown, Bettye C. Johnson, Jorge E. Neira
We describe a new type of Calibrated Hyperspectral Image Projector (CHIP) intended for radiometric testing of instruments ranging from complex hyperspectral or multispectral imagers to simple filter radiometers. The CHIP, based on the same digital mirror

Inside Diameter Measurements for the Cylinder of a 20 L Piston Prover

March 23, 2006
Author(s)
Jesus J. Aguilera, Tsyh Tyan Yeh, John D. Wright
We made inside diameter measurements of a stainless steel cylinder used in a piston prover for hydrocarbon liquid flow measurements. We used a 3-point micrometer and two traceable setting rings to measure diameter at 12 radial positions at each of 21

Low Background Temperature Calibration of Infrared Blackbodies

March 23, 2006
Author(s)
Adriaan C. Carter, Raju V. Datla, Timothy M. Jung, Allan W. Smith, James A. Fedchak
The Low Background Infrared (LBIR) facility at the National Institute of Standards and Technology (NIST) has performed 10 calibrations of low-background blackbodies since 2001 when the calibration facility and calibration method for low-background

Measurement of Small Apertures

March 23, 2006
Author(s)
James A. Fedchak, Adriaan C. Carter, Raju V. Datla
The Low Background Infrared calibration (LBIR) facility at the National Institute of Standards and Technology (NIST) is developing a relative aperture area instrument to measure the areas of apertures with diameters ranging from 5 mm to 0.05 mm. NIST

Status of High-Voltage, High-Frequency Silicon-Carbide Power Devices

March 22, 2006
Author(s)
Allen R. Hefner Jr.
The emergence of High-Voltage, High-Frequency (HV-HF) Silicon-Carbide (SiC) power devices is expected to revolutionize commercial and military power distribution and conversion systems. The DARPA Wide Bandgap Semiconductor Technology (WBST) High Power

Remotely Accessed Photovoltaic Power Experiment

March 21, 2006
Author(s)
W J. Hutzel, William M. Healy
A solar energy experiment that estimates the number of photovoltaic panels needed to provide supplemental power for a typical residence is described. The project is unique because it uses freely available on-line resources for collecting and analyzing

Characterizing Gaseous Air Cleaner Performance in the Field

March 20, 2006
Author(s)
Cynthia H. Reed, Steven J. Emmerich, Steven J. Nabinger
As part of an ongoing effort to better understand the performance of indoor air cleaners in buildings, the National Institute of Standards and Technology (NIST) has completed a series of gaseous air cleaner field tests and model simulations. This paper

Analysis of DNA Single Nucleotide Polymorphisms by Mass Spectrometry

March 17, 2006
Author(s)
Peter Vallone, John Butler
Single nucleotide polymorphisms(SNP) are the most frequent form of DNA sequence variation in the human genome and are becoming increasingly useful as genetic markers for genome mapping studies, medical diagnostics, and human identity testing. The primer

Conformational Changes Associated With Receptor-Stimulated Guanine Nucleotide Exchange in a Heterotrimeric G-Protein a-Subunit: NMR Analysis of the GTPgS-Bound States

March 17, 2006
Author(s)
K D. Ridge, N G. Abdulaev, Xi-Cheng Zhang, T Ngo, D M. Brabazon, John P. Marino
Solution NMR studies of a 15N-labeled G-protein ?-subunit (G?) chimera (15N-ChiT) reconstituted heterotrimer have previously shown that binding of ??-subunits induces a pre-activated conformation in G? that may facilitate interaction with R* and guanine

Phonon Broadening of Spectral Lines in Scanning Tunneling Spectroscopy

March 17, 2006
Author(s)
John William Gadzuk
The observation and interpretation of spectral lines associated with quasi-localized states in condensed matter systems has provided a rich source of information pertaining to the transient coupling of these states to their dynamic environment.1 While
Displaying 34626 - 34650 of 73832
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