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NIST Authors in Bold

Displaying 28976 - 29000 of 74303

Development of the Atomic and Molecular Data Markup Language for Internet Data Exchange

October 16, 2008
Author(s)
Y Ralchenko, R Clark, D Humbert, David R. Schultz, T Kato, Y J. Rhee
Accelerated development of the Internet technologies, including those relevant to the atomic and molecular physics, poses new requirements for the proper communication between computers, users and applications. To this end, a new standard for atomic and

DHS Leads the Way to Standards for Homeland Security

October 16, 2008
Author(s)
Laurie E. Locascio
In late April 2005, in response to a recently issued GAO report describing the urgent need for standards and validated methods related to biological incident response, Dr. Bert Coursey, head of the Standards Portfolio at DHS, charged NIST with the task of

Diameter Dependent Transport Properties of GaN Nanowire Field Effect Transistors

October 16, 2008
Author(s)
Abhishek Motayed, Mark D. Vaudin, Albert Davydov, John Meingailis, Maoqi He, S N. Mohammad
We report transport properties measurements of individual GaN nanowire field effect transistors and the correlation of the electron mobilities with the existence of grain boundaries in these nanowires. These nanowires are grown by direct reaction of NH3

Dielectric and Thermal Properties of Multi-Layer Polymer Films

October 16, 2008
Author(s)
W Sakai, T Yoshiji, N Tsutsumi, C. K. Chiang
The dielectric and thermal properties of three-layer structured films were studied. The two outer layers were about one microns and the thickness of middle layer was varied. We measured the thickness dependence of the dielectric constant of the three-layer

Dielectric Measurement Methods at Millimeter Wave Frequencies

October 16, 2008
Author(s)
Michael D. Janezic
We review several techniques for making accurate relative permittivity and loss tangent measurements of low-loss dielectric materials at frequencies between 30 and 100 GHz. Many conventional methods that operates at microwave frequencies are impracatical

Diffuse Reflectance of Sintered and Pressed Polytetrafluroethylene (PTFE)

October 16, 2008
Author(s)
P Y. Barnes, E A. Early
Polytetrafluoroethylene (PTFE) is widely used in applications requiring a material with a diffuse reflectance factor close to unity. The bidirectional reflenctance distribution function (BRDF) of both pressed and sintered samples was measured as a function

Diffusional Creep: Stresses and Strain Rates in Thin films and Multilayers

October 16, 2008
Author(s)
Daniel Josell, Timothy P. Weihs, H Gao
In this article, we discuss creep deformation as it relates to thin films and multilayer foils. We begin by reviewing experimental techniques for studying creep deformation in thin-film geometries, listing the pros and cons of each; then we discuss the use

Digital Rights, Risk and Assurance

October 16, 2008
Author(s)
Gordon E. Lyon
A trust and assurance perspective applies readily to the distribution of digital products over the Internet: It identifies when digital rights remain viable, even with eventual mishaps and leaks that attend every long-term operation. An assurance system

Directional Solidification in a AgCuSn Eutectic Alloy

October 16, 2008
Author(s)
Robert J. Schaefer, D J. Lewis
An experimental study of microstructures in a directionally solidified, near-eutectic solder Ag-Cu-Sn alloy has been completed. This material is an important candidate for use as a lead-free solder, and the studies show the origin and velocity dependence

Discrete Variable Representations for Singular Hamiltonians

October 16, 2008
Author(s)
B I. Schneider, N Nygaard
We discuss the application of the Discrete Variable Representation to Schr dinger problems which involve singular Hamiltonians. Unlike recent authors which invoke transformations to rid the eigenvalue equation of singularities at the cost of added

Dispersion and Shear Viscosity of a Simulated Polymer Nanocomposite

October 16, 2008
Author(s)
Francis W. Starr, Jack F. Douglas, S C. Glotzer
Using molecular dynamics simulations, we explore properties affecting nano-filler dispersion in a dense bead-spring polymer melt, and how the state of dispersion alters the response of the system to shear. We determine a simple metric to determine the

Dissolution Dynamics of Artificially Structured Materials

October 16, 2008
Author(s)
M Shima, L Salamanca-Riba, Thomas P. Moffat
The anodic dissolution of an ultrathin cobalt film buried beneath a copper overlayer has been studied using voltammetry and chronoamperometry. The films were produced by sequential electrodeposition of cobalt and copper layers from a solution of 1.5 mol/L

Distant Entanglement with Nearest Neighbor Interactions

October 16, 2008
Author(s)
G K. Brennen
Preparing many body entangled states efficiently using available interactions is a challenging task. One solution may be to couple a system collectively with a probe that leaves residual entanglement in the system. We investigate the entanglement produced

Domain Structures in Low Ionic Strength Polyelectrolyte Solutions

October 16, 2008
Author(s)
B D. Ermi, Eric J. Amis
A steep upturn at low angles dominates the small angle neutron scattering profile of low ionic strength polyelectrolyte solutions when measurements are extended to low angles not typical of most studies. This behavior is consistent with static and dynamic

Dosimetry of Beta-Ray Opthalmic Applicators: Comparison of Different Measurement Methods

October 16, 2008
Author(s)
Christopher G. Soares, S Vynckier, H Jarvinen, W G. Cross, J Hokkanen, P Sipila, D Fluhs, B Schaeken, F A. Mourtada, G A. Bass, T T. Williams
An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with radiochromic film, thermoluminescence dosimeters (TLDs), alanine pellets, plastic scintillators, an

Draft Radioanalytical Water and Soil Performance Testing Uncertainty Acceptance Criteria Derived From Historical Mixed-Analyte Performance Evaluation Program Results

October 16, 2008
Author(s)
Kenneth G. Inn, James J. Filliben, James Dahlgran
Radioanalytical performance testing programs provide radioassay laboratories, regulators and the public performance-based evidence that measurement capabilities are in control. Performance acceptance criteria that combine aspects of measurements difference

Dynamic Hardness of Porous and Nonporous Materials Using a Dropped Ball

October 16, 2008
Author(s)
R B. Clough
A method for measuring the dynamic hardness of materials using a dropped ball is developed and applied to nonporous cold-rolled plain carbon (1018) steel. A new feature of the method is that it corrects the hardness measurement for the effects of pile-ups
Displaying 28976 - 29000 of 74303