U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 1501 - 1525 of 1721

SANS Study of Sulfonate End Group Effect on Polystyrene Self-Diffusion

October 1, 2000
Author(s)
S D. Kim, A Klein, L H. Sperling, E M. Boczar, Barry J. Bauer
Film formation from a latex involves interdiffusion of the polymer chains. The interdiffusion behavior of polystyrene with H-ends, one sulfite-end, and two sulfite-ends are compared via small-angle neutron scattering (SANS) and a direct nonradiative energy

The Effect of Changing Molecular End Groups on Surface Properties: Synthesis and Characterization of Poly (Styrene-b-Semifluorinated Isoprene) Block Copolymers With -CF 2 H End Groups

October 1, 2000
Author(s)
T Hayakawa, J G. Wang, M Xiang, X Li, M Ueda, Christopher K. Ober, Jan Genzer, E Sivaniah, E J. Kramer, Daniel A. Fischer
Poly(styrene-b-semifluorinated isoprene) block copolymers with -CF 2H terminated side groups were synthesized by the esterification reaction of a poly(styrene-b-hydroxylated 1,2-/3,4-isoprene) block copolymer with semifluorinated acid chlorides. Two

The Ultra-Small-Angle X-Ray Scattering Instrument on UNICAT at the APS

October 1, 2000
Author(s)
Gabrielle G. Long, Andrew J. Allen, J Ilavsky, P R. Jemian, P Zchack
A new ultra-small-angle X-ray scattering (USAXS) instrument has been commissioned as part of the UNICAT facility on the 33-ID line at the Advanced Photon Source. The instrument offers continuously-tunable optics for anomalous USAXS, 1000 times the

Model for Cyclic Fatigue of Quasi-Plastic Ceramics in Contact with Spheres

September 1, 2000
Author(s)
K -. Lee, Yeon-Gil G. Jung, I M. Peterson, Brian R. Lawn, D H. Kim, S K. Lee
A model of contact damage accumulation from cyclic loading with spheres and ensuing strength degradation in relatively tough, heterogeneous ceramics is developed. The damage takes the form of a quasiplastic zone beneath the contact, consisting of an array

Assessment of Moisture Measurement Techniques for Ceramic Processing

August 1, 2000
Author(s)
P S. Wang
This report presents an assessment of moisture measurement tests by techniques currently available for ceramic processing applications. The techniques tested include near infrared, microwave, proton nuclear magnetic resonance, magnetic resonance imaging

Comparative of Texture Analysis Techniques for Highly Oriented a-Al 2 O 3

August 1, 2000
Author(s)
M M. Seabugh, Mark D. Vaudin, James Cline, G L. Messing
Texture measurements were performed on liquid phase sintered alumina textured by a templated grain growth process. Texture distributions were measured using four techniques (x-ray pole figure, rocking curve, and Rietveld refinement and stereological

Cracking of Brittle Coatings Adhesively Bonded to Substrates of Unlike Modulus

August 1, 2000
Author(s)
K -. Lee, Y W. Rhee, Douglas H. Blackburn, Brian R. Lawn, H Chai
The role of elastic mismatch in determining critical conditions for indentation fracture in brittle coatings on substrates of unlike modulus is investigated. A model transparent trilayer system, consisting of a glass coating layer bonded to a thick

Molecular Orientation of Single and Two-Armed Monodendron Semifluorinated Chains on Soft and Hard Surfaces Studied Using NEXAFS

August 1, 2000
Author(s)
Jan Genzer, E Sivaniah, E K. Kramer, J G. Wang, M Xiang, K Char, Christopher K. Ober, Robert A. Bubeck, Daniel A. Fischer, M Graupe, R Colorado, O E. Shmakova, T R. Lee
Near-edge absorption fine structure (NEXAFS) measurements are used to probe the molecular orientation of semifluorinated (SF) mesogens, -(CH 2)x(CF 2)yF, which are attached to I) the isoprene backbone of polyisoprene or a styrene-isoprene diblock copolymer

Vortex Pinning in Microindented Yba 2 Cu 3 O 7-x Single Crystals

August 1, 2000
Author(s)
Marina Turchinskaya, Douglas T. Smith, Alexander L. Roytburd, Debra L. Kaiser
A high resolution magneto-optical technique with a magnetic indicator film was used to study the effect of a regular array of micrometer-sized mechanical indentations on magnetization dynamics at the surface of a twinned single crystal of Yba 2Cu 3O 7-δ as

A Nanocomposite Poly(Methyl-Methacrylate) Bone Cement

July 1, 2000
Author(s)
A H. Gomoll, A Bellare, W Fitz, T S. Thornhill, R D. Scott, P R. Jemian, Gabrielle G. Long
Poly(methyl methacrylate) (PMMA) based orthopaedic bone cements contain 1-3 micro υ size radiopacifier particles. Incomplete dispersion of these particles leads to the presence of 50-200 micro υ size agglomerates. These large defects are sites of high

Abrasive Machining of Glass-Ceramics With a Dental Handpiece

July 1, 2000
Author(s)
X Dong, L Yin, S Jahanmir, L K. Ives, E D. Rekow
Machinable glass ceramics are used to prepare dental restorations with modern dental CAD/CAM systems. Unfortunately, little is understood about the influence of mahining parameters on material removal rates and any damage which could be introduced into the

Effect of Interfacial Layers on Wear Behavior of a Dental Glass-Ceramic

July 1, 2000
Author(s)
A Ravikiran, S Jahanmir
Wear studies on a glass-ceramic dental restorative material were performed under two types of lubrication conditions with distilled water. In one set of experiments, the contact interface was continuously flushed with fresh water to remove the wear debris

Fracture and the Structure of Silica

July 1, 2000
Author(s)
Stephen W. Freiman
Not only because of its historic and widespread use in applications where its strength and brittle nature are significant factors, but also because it is homogeneous in composition and structure, and isotropic in its properties, glass is an ideal medium in
Displaying 1501 - 1525 of 1721