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Displaying 2126 - 2150 of 4635

Improved Limits on Variation of the Fine Structure Constant and Violation of Local Position Invariance

May 29, 2007
Author(s)
Tara M. Fortier, Neil Ashby, James C. Bergquist, Marie Delaney, Scott A. Diddams, Thomas P. Heavner, Leo W. Hollberg, Wayne M. Itano, Steven R. Jefferts, K Kim, Windell Oskay, Thomas E. Parker, Jon H. Shirley, Jason Stalnaker, Filippo Levi, Luca Lorini
We report tests of Local Position Invariance (LPI) and constancy of fundamental constants from measurements of the frequency ratio of the 282-nm 199Hg + optical clock transition to the ground-state hyperfine splitting in 133Cs. Analysis of the frequency

A Mercury-Ion Optical Clock

September 9, 2001
Author(s)
James C. Bergquist, U Tanaka, Robert E. Drullinger, Wayne M. Itano, David J. Wineland, Scott A. Diddams, Leo W. Hollberg, E A. Curtis, Christopher W. Oates, T Udem
… A Mercury-Ion Optical Clock …

Measurement Methods for Materials Properties: Elasticity

February 19, 2017
Author(s)
Sheldon M. Wiederhorn, Richard J. Fields
Elastic constants must be obtained by experiment methods. Materials are too complicated and theory of solids insufficiently sophisticated to obtain accurate theoretic determinations of elastic constants. Usually, simple static mechanical tests are used to

A Constrained L2 Based Algorithm for Standardized Planar Datum Establishment

November 18, 2015
Author(s)
Craig M. Shakarji, Vijay Srinivasan
For years (decades, in fact) a definition for datum planes has been sought by ASME and ISO standards writers that combines the contacting nature of traditional surface plate mating with a means of balancing rocking conditions when there is a centrally

Evaluation of Cell Source for Tissue Engineered Ligament: Anterior Cruciate Ligament (ACL), Medial Collateral Ligament (MCL), Achilles Tendon (AT) and Patellar Tendon (PT)

October 16, 2008
Author(s)
James A. Cooper, L A. Bailey, Janell N. Carter, Cynthia Castiglioni, Michelle D. Kofron, Frank K. Ko, Cato T. Laurencin
This study investigated four different connective tissue cell types to determine which cell type is an optimal source for seeding a tissue-engineered Anterior Cruciate Ligament (ACL) replacement. Cells from the ACL, Medial Collateral Ligament (MCL)

High Pressure Gas-Coupled Ultrasonic Inspection for Discontinuities

April 1, 2000
Author(s)
R E. Schramm, C M. Fortunko
A liquid couplant is usually necessary between the transducer and the specimen for ultrasonic crack detection and thickness gaging. This work demonstrates the possibility of using pressurized gas as the couplant for noncontact inspection. Historically
Displaying 2126 - 2150 of 4635
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