U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 50701 - 50725 of 74186

A Well Collimated Quasi-Continuous Atom Laser

March 1, 1999
Author(s)
Edward W. Hagley, Lu Deng, M M. Kozuma, J Wen, Kristian Helmerson, S L. Rolston, William D. Phillips
We demonstrate extraction of sodium atoms from a trapped Bose-Einstein condensate (BEC) using a coherent stimulated Raman process. Optical Raman pulses drive transitions between trapped and untrapped magnetic sublevels so as to give the output coupled BEC

A Wide Bandwidth Printed Wiring Board Transmission Line Probe

March 1, 1999
Author(s)
Nicholas Paulter, Jon R. Pratt
An inexpensive, wide bandwidth, high cycle 50 ω probe is described for making electrical contact to printed wiring board planar transmission lines. The electrical transfer function of the probe and its contact repeatability are presented.

Analytic Solution for a Non-Axisymmetric Isothermal Dendrite

March 1, 1999
Author(s)
Geoffrey B. McFadden, Sam R. Coriell, R F. Sekerka
The Ivantsov solution for an isothermal paraboloidal dendrite growing into a pure, undercooled melt provides a relation between the bulk undercooling and a dimensionless product, the Peclet number, of the growth velocity and tip radius of the dendrite

Conformance Testing and Certification Model for Software Specifications

March 1, 1999
Author(s)
Lisa J. Carnahan, Lynne S. Rosenthal, Mark Skall
The use of conformity assessment as a means by which buyers and sellers can communicate requirements and conformance will increase as information technology systems and applications grow more complex. Models for conformance testing and certification

Curing of High-Performance Concrete: Report of the State-of-the-Art

March 1, 1999
Author(s)
K W. Meeks, Nicholas J. Carino
This report describes the latest information, technology, and research on the curing of high-performance concrete (HPC). The scope of the report is expanded somewhat to examine the current body of knowledge on the effects of various curing conditions on

Dielectric and Ultrasonic Anomalies at 16, 37, and 65 K in SrTiO 3

March 1, 1999
Author(s)
C Ang, J F. Scott, Z Yu, H M. Ledbetter, J L. Baptista
In this paper we report coincident anomalies in both dielectric response and sound velocities in strontium titanate around three temperatures 16.37 and 65 K. The anomalies occur in both single-crystal specimens and ceramics so they cannot be related to

Estimating the Virial Coefficients of the Ammonia + Water Mixture

March 1, 1999
Author(s)
L A. Weber
A corresponding states type model has been used to estimate the second and third virial coefficients of the NH 3 + H 2O mixture. Additional mixing parameters were added to the formulations for both coefficients to account for the chemical interactions

External Radiative Quantum Efficiency of 96 % from a GaAs/GaInP Heterostructure

March 1, 1999
Author(s)
H G. Gauck, T H. Gforerer, M J. Renn, Eric A. Cornell, Kristine A. Bertness
GaAs/GaInP double heterostructures are index matched with ZnSe hemispheres to increase the coupling of photoluminescence out of the device. We measure external quantum efficiencies as large as 96 % using a bolometric calibration technique. When the
Displaying 50701 - 50725 of 74186
Was this page helpful?