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Displaying 48051 - 48075 of 74292

Observation of Photons From an Inhibited Spontaneous Emitter

February 1, 2000
Author(s)
D A. Branning, Alan L. Migdall
A fun and timely problem in cavity quantum electrodynamics is the question of whether atoms are actually radiating anything when their spontaneous emission is inhibited by a cavity. Recent theoretical papers have indicated that the answer to this question

Phase Relations of the SrO-Ho 2 O 3 -CuO x System

February 1, 2000
Author(s)
Winnie K. Wong-Ng, J Dillingham, Lawrence P. Cook
The phase diagram of the SrO-R 2O 3-CuOx system, where R=Ho, was investigated in air. The tie-line relationships of this system were determined. Two ternary phases were found, namely, the green phase SrHo 2CuO 5 and the A14-24 solid solution (Sr 14-xHo x

Plasma Charge-Density Ratios in a Dusty Plasma

February 1, 2000
Author(s)
M A. Childs, Alan Gallagher
It is shown that particle diffusion in the afterglow of a dusty plasma can be used to establish several properties of the active plasma. Specifically, the ratio of the average mass of light negative and positive ions, and a limit for the ratio of electron

RF Material Characterization Using a Large-Diameter (76.8 mm) Coaxial Air Line

February 1, 2000
Author(s)
Chriss A. Jones, John H. Grosvenor Jr, Claude Weil
We report the development of a 76.84 mm (3.025 in) diameter coaxial air line system whose purpose is to measure the dielectric and magnetic properties of bulk dielectric and ferrite materials over a frequency range of approximately 0.3 - 1500 MHZ. We

Rotational Spectra of Seven Conformational Isomers of 1-Hexene

February 1, 2000
Author(s)
Gerald T. Fraser, R D. Suenram, C Lugez
The rotational spectra of 7 of the expected 13 conformational isomers of 1-hexene have been measured and assigned at a rotational temperature of 1 symmetry, as verified by the observation of a, b, and c-type electric-dipole transitions. The remaining

Secondary Ferrite Number Reference Materials: Gage Calibration and Assignment of Values

February 1, 2000
Author(s)
Christopher N. McCowan, Thomas A. Siewert, D P. Vigliotti, C M. Wang
Ferrite Numbers (FN) were assigned to blocks of stainless steel that serve as secondary ferrite reference materials (RM 8480 and 8481), and these specimens were placed in our Reference Materials inventory. These reference materials are used to calibrate

Setting the Standards

February 1, 2000
Author(s)
B C. Collins, W G. Leight
This invited article reviews the nature of the pluralistic standards system in the United States and its important relationships to product development, global activities, marketing, and trade. Emphasis is placed on the need to develop a National Standards

Small Particle Growth in Silane Radio-Frequency Discharges

February 1, 2000
Author(s)
M A. Childs, Alan Gallagher
Particle size and number density are measured versus discharge operating time in pure silane, capacitively-coupled RF discharges. Dischargeconditions are those typically used to produce amorphous silicon devices, except the temperature is 300K. Particle

Strengthening Composite Resin Restorations via Ceramic Whisker Reinforcement

February 1, 2000
Author(s)
Hockin D. Xu, Gary E. Schumacher, F Eichmiller, Joseph M. Antonucci
Due to their tendency to fracture, current composite for mulations are unsuitalbe for use in large stress-bearing direct posterior restorations that involve cusps. This study investigated the use of single-crystalline ceramic whiskers for the reinforcement

Subsolidus Phase Relations and Dielectric Properties in the SrO-Al 2 O 3 -Nb 2 O 5 System

February 1, 2000
Author(s)
Julia Y. Chan, Igor Levin, Terrell A. Vanderah, Richard G. Geyer, Robert S. Roth
Subsolidus phase equilibria in the SrO-Al 2O 3-Nb 2O 5 system were determined by synthesis of 75 compositions in air in the temperaturerange 1200-1600 C. Phase assemblages were determined by X-ray powder diffraction at room temperature. Two new ternary

Temperature Dependence of Molecular Orientation on the Surfaces of Semi-Fluorinated Polymer Thin Films

February 1, 2000
Author(s)
Jan Genzer, E Sivaniah, E K. Kramer, J G. Wang, H Koerner, K Char, Christopher K. Ober, B M. DeKoven, Robert A. Bubeck, Daniel A. Fischer, S Sambasivan
Near-edge X-ray absorption fine structure is used to investigate the temperature dependence of molecular orientation of semi-fluorinated liquid crystalline (SF-LC) mesogens, which are attached to the modified isoprene backbone of i) a polyisoprene

The Elastic Constants of Single Crystal Beta-Si 3 N 4

February 1, 2000
Author(s)
R Vogelgesang, M Grimsditch, Jay S. Wallace
Using Brillouin scattering, we have determined the five independent elastic constants of Β-Si 3N 4 single crystals. They are (in units of GPa) c 11 = 433(3), C 33=574(3), c 13 = 127(5), c 44 = 108(2), C 66 =119(4), and C 12 = C 11-2c 66 = 195(8), giving a

The Process Specification Language (PSL) Overview and Version 1.0 Specification

February 1, 2000
Author(s)
Craig I. Schlenoff, Michael Gruninger, Florence Tissot, John Valois, Joshua Lubell, Jonathan W. Lee
In all types of communication, the ability to share information is often hindered because the meaning of information can be drastically affected by the context in which it is viewed and interpreted. This is especially true among manufacturing systems

Ultracold Atom Collisions Probed With Ultrashort Laser Pulses

February 1, 2000
Author(s)
F K. Fatemi, Kevin Jones, Paul D. Lett
Photoassociation, the light-assisted formation of molecules, has become a powerful tool for studying weakly bound molecules, and for extracting atomic properties with high resolution. However, few experiments have focused on the dynamics of these
Displaying 48051 - 48075 of 74292