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The fundamental parameters approach to line profile fitting uses physically based models to generate the line profile shapes. Fundamental parameters profile fitting (FPPF) has been used to synthesize and fit data from both parallel beam and divergent beam
A Hexemer, E Sivaniah, E K. Kramer, M Xiang, X Li, Daniel A. Fischer, Christopher K. Ober
This report describes studies of surface coatings prepared from a semifluorinated monodendron surface-active block copolymer (SABC) used in combination with a thermoplastic elastomer (TPE) composed of poly(styrene-b-ethylene butylene-b-styrene). Since both
We present a new class of micropatterning techniques that incorporates a surface energy gradient on a single substrate. By combining microcontact printing and vapor deposition methods, this technique provides fast, reproducible, and high-quality micro
W S. Yoon, Mahalingam Balasubramanian, Xiao-Qing Yang, Ziwen Fu, Daniel A. Fischer, James McBreen
Soft X-ray (200 eV to 1000 eV) absorption spectroscopy (XAS) at the O K-edge and the metal L II, III-edges, in both the fluorescence yield (FY) and the partial electron yield (PEY) mode, has been used to probe the electronic structure of electrochemically
A study was made of the strength of highly polished silicon surfaces after nanoindentation with a Berkovich diamond. Strengths of the indented surfaces were measured as a function of flaw size, quantified by indenter penetration. Analogous data from etched
J Thomas, J J. Chen, Hamlin M. Jennings, Andrew J. Allen
Thin coupons of white portiand cement (WPC) and tricalcium silicate paste were decalcified by leaching in concentratedammonium nitrate solutions, resulting in calcium-to-silicon molar ratios (Ca/Si) ranging from 3.0 (control) down to 0.3. Themicrostructure
A Bayesian/Maximum entropy (MaxEnt) method is applied to quantify the broadening of X-ray line profiles in terms of the nanocrystallite size effects in ceria. The analysis is in general agreement with transmission electron microscopy results, while
W S. Yoon, C P. Grey, Mahalingam Balasubramanian, Xiao-Qing Yang, Daniel A. Fischer, James McBreen
Combined 6Li MAS NMR, in-situ metal K-edge (hard) XAS, and O K-edge (soft) XAS have been carried out during the first charging process for the layered Li1-xCo1/3Ni1/3Mn1/3O2 cathode material. The 6Li MAS NMR results showed the prescence of Li in the Ni2+
fects of different water-based grinding fluids on material removal rate, edge chipping damage and surface roughness in the abrasive machining of a micaceous glass, dental-type ceramic restorative material were investigated under simulated clinical-dental
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
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
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
S K. Lee, U Paik, Vincent A. Hackley, Y S. Jung, K J. Yoon
The influence of changes in the surface chemistry of colloidal BaTiO 3, due to the dissolution and adsorption/precipitation of Ba in an aqueous medium, on the microstructural development and permittivity of sintered BaTiO 3 powder compacts was investigated
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
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
We compare first-principles (FP) calculations of the ionic effective charges, phonon frequencies, and static dielectric permittivities k s of several perovskite-type materials. Transition metal ions have anomalously large effective charges, though in the
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