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NIST Authors in Bold

Displaying 31426 - 31450 of 74205

Measurement of Reactivity Ratios in Surface-Initiated Copolymerization

August 21, 2007
Author(s)
Derek L. Patton, Kirt A. Page, Chang Xu, Kirsten Genson, Michael J. Fasolka, Kathryn L. Beers
This work describes a new approach to measure monomer reactivity ratios from surface-initiated copolymerizations using x-ray photoelectron spectroscopy. Styrene/methyl methacrylate statistical copolymer brushes were prepared from various monomer feeds by

Multiplexed microcalorimeter arrays for precision measurements from microwave to gamma-ray wavelengths

August 21, 2007
Author(s)
Joel Ullom, W.Bertrand (Randy) Doriese, James A. Beall, William Duncan, S. L. Ferreira, Gene C. Hilton, Rob Horansky, Kent D. Irwin, Terrence J. Jach, John Mates, Nathan A. Tomlin, Galen O'Neil, Carl D. Reintsema, Nicholas Ritchie, Dan Schmidt, Leila R. Vale, Yizi Xu, Barry L. Zink, Andrew Hoover, Clifford R. Rudy, Derek Tournear, Duc Vo, Michael W. Rabin
Cryogenic microcalorimeters are a promising technology for ultrasensitive measurements of electromagnetic radiation from microwave to gamma-ray wavelengths. Cryogenic microcalorimeters derive their exquisite sensitivity from the minimal thermal noise at

High Effeciency Fast Scintillators for the Development of Optical Soft X-Ray Arrays for Laboratory Plasma Diagnostics

August 20, 2007
Author(s)
L F. Delgado-Aparicio, R Vero, D Stutman, M Finkenthal, K Tritz, G Suliman, H W. Moos, R Kaita, R Majeski, B Stratton, L Roquemore, D Johnson, Charles Tarrio
Scintillator-based optical soft x-ray (OSXR) arrays may in the near future, replace the conventional diode arrays used for plasma imaging, tomographic reconstruction, magnetohydrodynamics, transport and turbulence studies in magnetically confined fusion

Mapping Cell Distribution in Amorphous Scaffolds using Confocal Microscopy

August 19, 2007
Author(s)
Jirun Sun, Nancy Lin, Marcus T. Cicerone, Sheng Lin-Gibson
One common method for probing cell-material interactions is direct visualization via confocal laser scanning microscopy, a technique widely used for studying biological systems. However, confocal microscopy has limited depth penetration for imaging cells

Current Status of Thermodynamic Properties of Hydrogen

August 17, 2007
Author(s)
Bryce Jacobson, Jacob W. Leachman, Steven Penoncello, Eric Lemmon
This paper presents a survey of the thermodynamic properties of normal hydrogen and parahydrogen with comparisons of properties calculated using the standard models to available experimental data. Motivated by the fact that the currently accepted standards

Test Methods and Knowledge Representation for Urban Search and Rescue Robots

August 17, 2007
Author(s)
Craig I. Schlenoff, Elena R. Messina, Alan M. Lytle, Brian A. Weiss, Ann M. Virts
In this paper, we described an effort in which NIST is working with FEMA Task Force members to define performance requirements and standard test methods as well as to assess the deployment potential of robots applied to the USAR domain. This process has

Spinor Dynamics in an Antiferromagnetic Spin-1 Condensate

August 16, 2007
Author(s)
A T. Black, Eduardo Gomez, Lincoln Turner, Sebastian Jung, Paul D. Lett
We observed coherent spin oscillations in an antiferromagnetic spin-1 Bose-Einstein condensate of sodium. The variation of the spin oscillations with magnetic field shows a clear signature of nonlinearity, in agreement with theoretical predictions that

Two-Phonon Infrared Spectra of Si and Ge: Calculating and Assigning Features

August 16, 2007
Author(s)
Eric L. Shirley, Hadley Lawler
Third-order density-functional perturbation theory yields the terahertz/far-infrared absorption spectra for silicon and germanium, including all two-phonon combination and difference features. Temperature-dependent spectra are compared to available

A Study of Comparability in AFLP Profiling Using a Simple Model System

August 15, 2007
Author(s)
Lina Partis, M J. Burns, Koichi Chiba, Ph Corbisier, Marcia J. Holden, J. Wang, Qing Y. Liu, Tomoya Okunishi, Sang-Ryoul Park, Maxim Vonsky, K R. Emslie
A simple AFLP model, using the relatively small bacteriophage lambda genome, was developed to test the reproducibility of this technique in an international study, CCQM-P53. Using either non-selective or selective primers, 9 fragments or a subset of 1 to 3

Collaborative Augmented Reality for Better Standards

August 15, 2007
Author(s)
Matthew L. Aronoff, John V. Messina
Concurrent engineering depends on clear communication between all members of the development process. As that communication becomes more and more complex -- including not only textual descriptions, but CAD models, diagnostic data, process control data, and

Facial Respirator Shape Analysis using 3D Anthropometric Head Data

August 15, 2007
Author(s)
Riley Fenlon
For firefighters and first response crews, the facial respirator is the first and last defense against hazardous and potentially harmful airborne agents. That defense is crippled if the seal of the respirator sprouts a leak, exposing the wearer to the

Demonstration of high-performance chip-scale magnetic shields

August 14, 2007
Author(s)
Elizabeth A. Donley, Eleanor Hodby, Leo W. Hollberg, John E. Kitching
We have designed and tested a set of five miniature nested magnetic shields constructed of high-permeability material, with volumes ranging from 0.01 to 2.5 cm^3. We present measurements of the longitudinal and transverse shielding factors (the ratio of

Relaxation Behavior of Polymer Structures Fabricated by Nanoimprint Lithography

August 14, 2007
Author(s)
Yifu Ding, Hyun Wook Ro, Thomas A. Germer, Jack F. Douglas, Brian C. Okerberg, Alamgir Karim, Christopher L. Soles
We study the decay of the imprinted polystyrene (PS) patterns under thermal annealing using light diffraction. The first order diffraction intensity from the imprinted gratings was measured as a function of annealing time. Local intensity maximum is

Where EAP Security Claims Fail

August 14, 2007
Author(s)
Katrin Hoeper, Lei Chen
The Extensible Authentication Protocol (EAP) is widely used as an authentication framework to control the access to wireless networks, e.g. in IEEE 802.11 and IEEE 802.16 networks. In this paper, we discuss limitations of EAP security and demonstrate how

Instability of Flatband Voltage in HfO2 Gate Stack Structures under Reducing/Oxidizing Annealing Conditions

August 13, 2007
Author(s)
K Ohmori, P Ahmet, M Yoshitake, T Chikyow, K Shiraishi, K Yamabe, H Watanabe, Y Akasaka, Kao-Shuo Chang, Martin L. Green, K Yamada
We have applied a combinatorial approach to fabricate work function (WF) tuned Pt-W alloy films and used the films as metal electrodes for HfO2/SiO2/Si capacitors. As the ratio RPt of Pt to W changes from 0 to 1, the WF value varies continuously from 4.7

Selectable Resistance-Area Product by Dilute Highly Charged Ion Irradiation

August 13, 2007
Author(s)
Joshua M. Pomeroy, Holger Grube, A C. Perrella, John D. Gillaspy
In order to provide high performance read heads for future hard drive densities, considerable effort worldwide has been invested in developing techniques for producing low resistance area product (RA) magnetic tunnel junction sensors. In this letter, we
Displaying 31426 - 31450 of 74205