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S A. Prosandeev, U Waghmare, Igor Levin, James E. Maslar
First principles computations of Raman intensities were performed for perovskite-like compound CaAl1/2Nb1/2O3 (CAN). This compound features 1:1 (NaCl-type) ordering of Al and Nb superimposed onto the b-b-c+ octahedral tilting. Raman tensor for CAN was
Well prepared strength test specimens and components break from a material s inherent flaws and machining damage has no effect on strength. On the other hand, grinding can create machining flaws that control strength and limit the performance of finished
Micromagnetic calculations are used to determine the eigenfrequencies and precession patterns of some of the lowest-frequency magnetic normal modes of submicron patterned elements. For a Permalloy-like ellipse, 350 nm 160 nm 5 nm thick in zero field, the
Strained epitaxial growth of Ge on Si(001) produces self-assembled, nanometer scale islands, or quantum dots. We study this growth by atomistic simulation, computing the energy of island structures to determine when and how islanding occurs. The
John W. Hastie, D W. Bonnell, C Chatillon, J Drowart
An assessment of the high temperature mass spectrometric technique is given, with emphasis on sources of inaccuracy, particularly ionization cross sections. Data -- experimental, calculated, and estimated -- are summarized for ionization cross sections of
The Recommended Practice Guide describes nearly 200 standard measurement methods (standards) used by the surface engineering community. The standards compiled address inorganic (metal and ceramic) materials used in structural applications. The Guide is
To facilitate the evaluation of dental composites, high throughput methods to fabricate dental resins with varying conversion levels were developed. Resins of 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]propane (Bis-GMA) and triethylene glycol
L A. Bailey, Matthew Becker, James A. Cooper, J Kohn, Eric J. Amis
The evaluation and identification of detrimental interactions between biological species and synthetic surfaces is a daunting challenge as the number of materials and control of physical variables increases. In this talk, the physical properties of
T Hemraj-Benny, S Banerjee, S Sambasivan, Daniel A. Fischer, W Han, J A. Misewich, S S. Wong
Herein, we demonstrate that NEXAFS is a very effective technique at (a) identifying the phases of boron nitride nanotubes with the potential of distinguishing between hexagonal BN and cubic BN, and (b) monitoring the presence of defects and degree of
Ying Mei, Tao Wu, Chang Xu, K J. Langenbach, John T. Elliott, B D. Vogt, Kathryn L. Beers, Eric J. Amis, N Washburn
In this study, a simple and versatile method was developed to prepare the low grafting density initaitor gradient, which was combined with surface initiated atom transfer radical polymerizations (ATRP) to produce a well defined poly(2-hydroxyethyl
Zuzanna T. Cygan, J Cabral, Kathryn L. Beers, Eric J. Amis
Rapid prototyping photolithography of a thiolene based resin was used to fabricate microfluidic devices stable to aliphatic and aromatic organic solvents. The swelling of the thiolene resin in various organic solvents was quantified and the solvent
Martin Y. Chiang, Xianfeng Wang, Carl R. Schultesiz
A three-dimensional fiber tow-based analytical model incorporating shear-lag theory and a statistical strength distribution has been used to simulate the tensile properties and predict the tensile strength of unidirectional hybrid composites. The hybrid
S Bencherif, K S. Wilson, Elizabeth Wilder, Joseph M. Antonucci
Dimethacrylate monomers of several types are widely used in preventative and restorative dental applications. One such monomer that ushered in the modern era of polymeric based dental materials is 2,2-bis[p-(2'-hydroxy-3'-methacryloxyoxypropoxy)phenyl]
D J. Burnett, A M. Gabelnick, J L. Gland, Daniel A. Fischer
In situ studies of ethylene oxidation on Pt(111) have been performed using a powerful combination of fluorescence yield soft x-ray methods for temperatures up to 600 K and oxygen pressures up to 1.3 Pa. Absolute carbon coverages have been determined both
Boundary lubricating films are critical in effective lubrication of engine components. Their formation mechanism has not been fully understood because of the large variations of chemistry and machinery in operation. Various reports on boundary lubricating
This chapter offers a comprehensive summary of current understanding in boundary lubrication and the formation of boundary lubricating films. Classical and modern definitions of boundary lubrication are presented which serve to define the scope of boundary
Youn S. Kang, Lawrence H. Robins, Anthony Birdwell, Alexander J. Shapiro, W. R. Thurber, Mark D. Vaudin, M M. Fahmi, D Bryson, S N. Mohammad
The electronic structure of Si-doped InyGa1-yAs1-xNx films on GaAs substrates, grown by nitrogen-plasma-assisted MBE, was examined by photoreflectance (PR) spectroscopy at temperatures between20 K and 300 K. The measured critical-point energies were
L R. Pattison, A Hexemer, E K. Kramer, P Petroff, Daniel A. Fischer
There has been great interest in recent years in using solution processible conjugated organic polymers as the active layers in semiconducting devices including field-effect transistors (FETs), light emitting diodes (LEDs), and photovoltaics (PVs). The
R Song, Martin Chiang, A J. Crosby, Alamgir Karim, Eric J. Amis, Naomi Eidelman
The self-adhesion behavior of an optically smooth poly(methyl methacrylate) (PMMA) thin film (ca.. 100 nm) on different evaporated metal substrates has been investigated using a combinatorial method approach. In this investigation through high-throughput
S Banerjee, T Hemraj-Benny, S Sambasivan, Daniel A. Fischer, J A. Misewich, S S. Wong
Probing order in nanotube systems is of fundamental importance in devising applications of these tubes in field emission applications as well as components of composite materials. We demonstrate near-edge X-ray absorption fine structure (NEXAFS)
A method is presented for generating approximate lattice Wannier functions (LWF) for lattice dynamics problems, using the dynamical matrix for a supercell as input. The lattice Wannier functions fit selected phonon frequencies and eigenvectors exactly, are