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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
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
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
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
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
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
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
Researchers use crystallographic information on a daily basis to visualize, explain, and predict the behavior of chemicals and materials. The NIST structural Database (NSD) contains crystallographic and atomic positional information for metallic
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
A front-tracking finite element method is used to compute the evolution of a crack-like defect that propagates along a bi-material interface by stress driven corrosion. Depending on material properties, loading, and temperature, simulations predict five
An analytical result has been obtained for the value of the dynamical charge necessary for calculations of oxygen vacancy kinetics in dielectric perovskite-type crystals. It is shown by using the Berry phase analysis that this charge equals the nominal
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 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