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Mi-Hye Jang, Winnie K. Wong-Ng, Robert D. Shull, Lawrence P. Cook, DeaSik Suh
Alternating current (AC) losses of two Bi-2223 ([Bi, Pb] : Sr : Ca : Cu :O = 2:2:2:3) tapes [one untwisted (Tape I, twist-pitch of mm) and the other with a twist-pitch of 8mm (Tape II)] were measured and compared. These samples, produced by the powder-in
The issue of scale in the fracture and deformation properties of ordinarily brittle covalent ionic solids (ceramics) is considered. Characteristic scaling dimensions for nanomechanical properties of this class of solids are identified specimen size or
Compositionally graded combinatorial films have been characterized by a high throughput automated spectroscopic reflectometer. The data from this instrument were used to map the thickness and index of refraction of the compositionally varying films
Anthony J. Bur, S C. Roth, Y E. Lee, N Noda, M M. McBrearty
A new multi purpose instrument has been used to obtain real-time dielectric and fluorescence spectroscopy from polymer resins compounded with inorganic fillers. The istrument, which is mounted at the exit of an extruder, contains a flow-through slit
Three commercial dental composites with filler loading of 75-76 wt% were evaluated. The wear results were compared with those reported in an earlier study on a highly filled composite containing predominately alumino-silicate glass fillers and alumina at a
Charles M. Guttman, S Wetzel, Kathleen M. Flynn, B M. Fanconi, William E. Wallace, David L. VanderHart
NIST has sponsored a MALDI-TOF-MS interlaboratory comparison of mixtures of polymers of the same repeat unit with closely matching molecular masses but with different end groups. This interlaboratory comparison was designed to see how well a group of labs
Daniel A. Fischer, K Efimenko, R R. Bhat, S Sambasivan, Jan Genzer
Mapping the bond chemistry and molecular orientation of self-assembled monolayer gradients on flat surfaces and reaction intermediates in catalyst arrays is made possible using combinatorial near-edge X-ray absorption fine structure (NEXAFS). These
An atomic force microscope (AFM) was used to measure the tan delta of a pressure sensitive adhesive transfer tape as a function of frequency (0.01 Hz to 100 Hz). For the measurement, the sample was oscillated normal to the surface and the response of the
Commensurate with NIST s mission to advance the state of quantitative measurement science we have worked to develop a method to determine absolute molecular mass distribution of synthetic polymers by mass spectrometry. Work has centered on using matrix
Since its use as a compound for matrix assisted laser desorption/ionization (MALDI), 2,5 dihydroxybenzoic acid (DHB) has been the subject of many solid state and gas phase studies. Here, the temperature of DHB during LD experiments was raised from +20C to
Y N. Deng, P Miranda, Antonia Pajares, Brian R. Lawn
Fracture damage in trilayers consisting of outer and inner brittle layers bonded to a compliant (polycarbonate) substrate and subjected to concentrated surface loading is analyzed. The principal mode of fracture is radial cracking at the undersurface of
M M. Fahmi, A Kahn, J A. Griffin, G L. Harris, Larry Robins, Anthony G. Birdwell, Youn S. Kang, D J. Smith, T Steiner, S N. Mohammad
The dependence of the fundamental band gap and higher-lying critical-point energies of dilute-nitrogen Ga 1-yIn yAs 1-xN x epilayers on nitrogen mole fraction (x), for x less than or equal to} 0.0125, and temperature, from 20 K to 295 K, was investigated
Gale A. Holmes, Walter G. McDonough, Joy P. Dunkers, Charles C. Han
The interaction between fiber breaks in an E-Glass/Epoxy 2-D multifiber array that form matrix cracks during fiber fracture is presented. In contrast to the theoretical predictions of Hedgepeth and van Dyke (1967) the failure sites in fibers adjacent to a
Tissue engineered medical products (TEMPs) often consist of a three-dimensional synthetic scaffold that provides form and foundation for the cells as they produce the tissue of interest. Successful TEMPs will allow cell infiltration, and foster
W Ren, S Y. Yang, H. W. Fang, Stephen M. Hsu, P H. Wooley
Orthopedic wear debris has been thought to be an important factor associated with aseptic loosening. Our previous studies showed that variant shapes of UHMWPE particles induced diverse cellular and apoptotic responses. This continuing study investigated
Ultra-high-molecular-weight polyethylene (UHMWPE) wear particles have been recognized as the cause of aseptic loosening in total joint replacement. Macrophage phagocytosis of wear particles induces human biological/physiological responses which eventually
This paper updates and expands upon previously published information on MatML, a new extensible markup language designed specifically for the exchange of materials information. In particular, it will describe the strengths of MatML from the perspective of
Igor Levin, T G. Amos, S M. Bell, L Farber, Robert S. Roth, Terrell A. Vanderah, B H. Toby
Phase equilibria in the (1-x)BaZrO 3-xCaZrO 3 system were analyzed using a combination of X-ray and neutron powder diffraction, and transmission electron microscopy. The proposed phase diagram features two extended two-phase fields containing mixtures of a
Shozo Takagi, Laurence C. Chow, S Hirayama, A Sugawara
A self-hardening calcium phosphate cement (CPC-I), consisting of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA), has been shown in clinical studies to be efficacious as bone repair materials. The hardening time (HT) of the cement is