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NIST Authors in Bold

Displaying 226 - 250 of 1316

Nanofriction: The Observation of Elastic Plowing

February 19, 2017
Author(s)
Z C. Ying, Stephen M. Hsu
Accurate friction measurement at nanoscale is critical in reliable device design. Literature papers have reported different friction values for the same materials pair when different instruments and tip sizes were used. We have conducted a series of

Nanotechnology--From Promising to Practical: The Role of Standards

February 19, 2017
Author(s)
Stephen W. Freiman
Products based upon nanotechnology represent a potential market for revolutionary new materials, particularly those where one or more dimension is less than 50 nm, e.g., films, carbon nanotubes, nanoparticles. Commercialization of materials such as these

Nanotribology: the Link to Macrotribology

February 19, 2017
Author(s)
Stephen M. Hsu
The study of adhesion, friction, and lubrication at the nanoscale is driven by the needs in niicrosystems, MEMS, and small scale devices. Reliabilitydurability of these devices depend on the ability to control these properties. Furthermore, if fast-moving

Negative Pressure in Water Capillary Bridges at Nanocontacts

February 19, 2017
Author(s)
Seung H. Yang, Michael Nosonovsky, Huan Zhang, Koo-Hyun Chung
Negative Laplace pressure may develop inside a water capillary bridge formed between two bodies and contribute to the force required to pull them apart. Because of the negative pressure, nanoscale water capillary bridges may not be stable. We show that

New Synchrotron X-Ray Techniques for In-Situ Deformation Studies

February 19, 2017
Author(s)
Lyle E. Levine, R Thomson, Gabrielle G. Long, David R. Black
Many types of defects contribute to local and long-range stresses and strains in materials. These include vacancies, voids, prismatic loops, interstitials, inclusions, and dislocations. In most cases, dislocations play the dominant role in minimizing long

NIST Interactive Data Evaluation Assessment Tool

February 19, 2017
Author(s)
R G. Munro
Data evaluation levels provide a means of classifying property data according to how the data were acquired, processed, and reported. The present protocol is based on the seven categories of acceptable data that are discussed in the NIST Recommended

NIST Researcher Highlights Challenges of Talking Ceramics

February 19, 2017
Author(s)
Terrell A. Vanderah
In the last three decades, communications technologieshave been completely transformed by the wirelessrevolution. Devices such as cell phones are now socommon that many consumers are forgoing the hardwiredversions altogether. This remarkable

Nuclear Magnetic Resonance and X-Ray Absorption Spectroscopic Studies of Lithium Insertion in Silver Vanadium Oxide Cathodes

February 19, 2017
Author(s)
N D. Leifer, A Colon, K Martocci, S G. Greenbaum, Faisal Alamgir, T B. Reddy, N R. Gleason, R A. Leising, E S. Takeuchi
Structural studies have been carried out on Ag2V4O11 (silver vanadium oxide, SVO) and LixAg2V4O11, lithiated SVO with x = 0.72, 2.13 and 5.59 using Nuclear Magnetic Resonance (NMR) and X-ray Absorption Spectroscopy (XAS). Lithium-7 NMR indicates the

Optical and Structural Studies of Strain-Relaxed InxGa1-xN Films on GaN/sapphire with 0.04

February 19, 2017
Author(s)
Larry Robins, J T. Armstrong, Mark D. Vaudin, Charles E. Bouldin, Joseph Woicik, Albert J. Paul, W. R. Thurber, Ryna B. Marinenko
The structures of a set of InxGa1-xN films grown by atmospheric-pressure MOCVD onGaN buffer layers on c-plane sapphire, with compositions in the range 0.04 x 0.47, were characterized by x-ray diffraction (XRD). Several films were also examined by

Particulate Ceramic Composites: Their High-Temperature Creep Behavior

February 19, 2017
Author(s)
Sheldon M. Wiederhorn
Particulate composites, such as liquid-phase sintered silicon nitride and reaction-bonded silicon carbide, are being considered for use in applications where superior chemical and mechanical behavior at high temperatures are essential. Superior strength

Phase Diagrams for Zirconium and Zirconia Systems

February 19, 2017
Author(s)
H Ondik, H F. McMurdie
This compilation is the first volume in the Phase Equilibria Diagram series focused on a single element, zirconium. The volume combines over 400 new results with diagrams and commentaries published previously to form a focused collection of 1020 diagrams

Phase Equilibria Data for Electronic Ceramics Published

February 19, 2017
Author(s)
Terrell A. Vanderah
The first volume of a collection of phase diagrams focused on the increasingly important field of electronic ceramics was presented to the American Ceramic Society (ACerS) at its annual meeting in April 2003. The new volume details the phase equilibria of

Phase Equilibria Diagrams - Volume XIII: Oxides

February 19, 2017
Author(s)
Robert S. Roth
This volume is the thirteenth of the topically-oriented series of phase diagram compilations and the eighth to appear since the National Institute of Standards and TEchnology (NIST) and the American Ceramic Society (ACerS) embarked on a jointly-sponsored

Phase Equilibria of the High Tc Superconductors in the (Bi, Pb) -SR-Ca-Cu-O System

February 19, 2017
Author(s)
Winnie Wong-Ng, Lawrence P. Cook, W Greenwood, Anthony J. Kearsley
Applications of (Bi,Pb)-Sr-Ca-Cu-O phase equilibria include material synthesis, melt processing and single crystal growth. Both liquidus and subsolidus data are of central importance. For the determination of liquidus data, we have used a wicking technique

Phase Relations in Ba-(Nd,Eu,Gd)-Cu-O Coated Conductor Films

February 19, 2017
Author(s)
Winnie Wong-Ng, Igor Levin, Joseph J. Ritter, Lawrence P. Cook, Guangyao Liu, Makoto Otani, Christopher E. Lucas, Shailee P. Diwanji, Ron Feenstra, P Goyal, Mark D. Vaudin
Knowledge of phase relations in thin films of Ba2RCu3O6+x (where R=lanthanides or mixed lanthanides) is needed to guide the processing of coated conductors. High-temperature X-ray diffraction studies of Ba2RCu3O6+x films deposited using the

Phase-Correct Bond Lengths in Crystalline-Ge x Si l-x Alloys

February 19, 2017
Author(s)
Joseph Woicik, K E. Miyano, C A. King, R W. Johnson, J G. Pellegrino, T L. Lee, Z H. Lu
Extended x-ray absorption fine structure performed at the Ge-K edge has determined the Ge-Ge and Ge-Si bond lengths in a series of crystalline-Ge l-x alloys (x [greater than/less than] 0.5) to be compositional dependent. This high-precision measurement was

Polarization Dependence of Raman Peak Heights in the Absence of an Analyzer

February 19, 2017
Author(s)
Grady S. White, L M. Braun, M I. Bell
The general expression relating Raman scattering intensity to incident and scattered polarization directions is modified to account for an experimental configuration without an analyzer. This expression, combined with the known polarizability tensors for

Practical Intrinsic-Error Bounds for X-Ray Computed Tomography

February 19, 2017
Author(s)
R D. Spal
Images produced by x-ray computed tomography contain intrinsic error due to the limited spatial resolution of the technique. Two bounds on the mean intrinsic error over a specified region are determined, given only minimal information about the object

Predicting Fracture Resistance of Brittle Crystals

February 19, 2017
Author(s)
Grady S. White, Stephen W. Freiman, Lin-Sien H. Lum
A simple expression is derived relating fracture surface energy to easily measured material properties, i.e., the elastic Young's modulus and the equilibrium atomic plane spacing via a proportionality constant, k. This expression appears to be independent

Predictive chemical kinetic model for lubricant performance: bench testings

February 19, 2017
Author(s)
Stephen M. Hsu, C I. Chen
Bench tests have been used to screen lubricants and additives for industrial fluids in machinery applications for a very long time. As technology becomes more sophisticated in terms of materials, controls, and design, the need for simple, quick, and cheap
Displaying 226 - 250 of 1316