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Displaying 1001 - 1025 of 1721

Elastic Instability of Multilayer Films Coated on Substrates

January 1, 2005
Author(s)
Shu Guo, Martin Y. Chiang, Christopher M. Stafford
Mechanical properties of ultra-thin (submicrometer) films coated on a substrate are paramount in many applications. One question arises as to whether the physical and mechanical properties of supported thin films in applications can be significantly

Stress Analysis for Combinatorial Buckling-Based Metrology of Thin Film Modulus

January 1, 2005
Author(s)
Shu Guo, Christopher M. Stafford, Martin Y. Chiang
We recently reported on a new buckling-based metrology for probing the elastic modulus of thin polymer films. In this experimental geometry, a thin film of interest is transferred to a relatively thick elastic substrate, and buckling is induced by

Synthesis and Characterization of Poly(ethylene glycol) Dimethacrylate Hydrogels

January 1, 2005
Author(s)
Sheng Lin-Gibson, S Bencherif, Joseph M. Antonucci, Horkay F. JonesRL
Facile synthesis and detailed characterization of photo-polymerizable and biocompatible poly(ethylene glycol) dimethacrylates (PEGDM) and their hydrogels are described. Combined analyses of 1H NMR and MALDI-TOF MS confirmed the formation of prepolymers of

Array Ordering in Dendritic Crystals and the Influence on Crystal Perfection

December 1, 2004
Author(s)
R E. Napolitano, David R. Black
In the work reported here, several important issues regarding the role of the evolving dendritic structure in the generation of crystal defects are investigated. Industrially produced single-crystal castings are examined, and the dendritic arrays are

Contact Damage in Brittle Coating Layers: Influence of Surface Curvature

December 1, 2004
Author(s)
T Qasim, M T. Bush, X Z. Hu, Brian R. Lawn
Fracture from indentation by a hard sphere on bilayer systems composed of curved brittle coating layers on compliant polymeric substrates is investigated, in simulation of dental crown structures. Glass plates 1 mm thick are used are used as representative

Competing Damage Modes in All-Ceramic Crowns: Fatigue and Lifetime

November 15, 2004
Author(s)
Yu Zhang, Brian R. Lawn
A study is made of fracture from cyclic loading of WC spheres on the surfaces of brittle layers on compliant substrates, as representative of repetitive occlusal contact on dental crowns. Several damage modes radial cracks at both top surface and

Permeability of Polymeric Scaffolds With Defined Pore Micro-Architecture and Interconnectivity Fabricated by Solid Free-Form Microprinting

November 7, 2004
Author(s)
K W. Lee, E Jabbari, L L. Lu, B L. Currier, Joy Dunkers, Martin Chiang, John A. Tesk, Marcus T. Cicerone, M J. Yaszemski
The hydraulic permeability of was measured as a function of interconnectivity of the pores. The hydraulic permeability of porous scaffolds for tissue engineering of bone was measured as interconnectivity of the pores was changed from 100 % to 70 %. The

Control of Surface Properties Using Fluorinated Polymer Brushes Produced by Surface-Initiated Controlled Radical Polymerization

November 1, 2004
Author(s)
L Andruzzi, A Hexemer, X Li, Christopher K. Ober, E K. Kramer, Giancarlo Galli, E Chiellini, Daniel A. Fischer
Surface-grafted styrene-based homopolymer and diblock copolymer brushes bearing semifluorinated alkyl groups were synthesized by nitroxide-mediated controlled radical polymerization on planar silicon oxide surfaces. The polymer brushes were characterized

The Importance of Distributed Loading and Cantilever Angle in Piezo-Force Microscopy

November 1, 2004
Author(s)
B D. Huey, C Ramanujan, M Bobji, J Blendell, Grady S. White, R Szoszkiewicz, A Kulik
Piezo-force microscopy (PFM) is a variation of atomic force microscopy that is widely applied to investigate piezoelectric thin films at the nanometer scale. Curiously, PFM experiments are found to be remarkably sensitive to the position along the
Displaying 1001 - 1025 of 1721