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The 2009 Materials Science and Technology Conference and Exhibition (MS&T09) took place at the David L. Lawrence Convention Center in Pittsburgh , Pennsylvania, from October 25-29. The Conference was the leading forum addressing structure, properties
Fan Zhang, Andrew Allen, Lyle E. Levine, Laura Espinal, Joseph M. Antonucci, Drago Skrtic, Justin N. O'Donnell, Jan Ilavsky
The local structural changes in amorphous calcium phosphate (ACP) based dental composites were studied upon heating using both static, bulk measurement techniques and recently developed ultra-small angle X-ray scattering - X-ray photon correlation
Kirt A. Page, Derek Patton, Emily Hoff, Michael J. Fasolka, Kathryn Beers
This article describes a robust approach to measure monomer reactivity ratios from surface-initiated copolymerization, by measuring composition of statistical copolymer brush surfaces using x-ray photoelectron spectroscopy. Statistical copolymer brushes
We identify the reaction network governing gold monolayer protected cluster (MPC) formation during the reduction of Au(PPh 3)Cl and L 5 (L 5 = 1,5-bis(diphenylphosphino)pentane) in solutions. UV-vis spectroscopy and electrospray ionization mass
Nicholas Nanninga, Yaakov Levy, Elizabeth S. Drexler, Ryan Condon, April Stevenson, Andrew J. Slifka
The tensile properties of API-5L grades X52, X65, and X100 pipeline steels have been measured in a high pressure (13.8 MPa) hydrogen gas environment. Significant losses in elongation to failure and reduction in area were observed when testing in hydrogen
Christopher C. White, Donald L. Hunston, Kar T. Tan
The durability of building joint sealants is generally assessed using a descriptive methodology involving visual inspection for defects. It is widely known that this methodology has many inherent limitations and is only qualitative in nature. A new test
Santanu S. Kundu, Peter M. Johnson, Kathryn L. Beers
Using a model developed for the enzyme catalyzed polymerization and degradation of poly(caprolactone), we illustrate methods and the kinetic mechanisms necessary to improve molecular mass distributions by manipulating equilibrium reactions in the kinetic
Christopher Soles, Ryan Nieuwendaal, Huagen H. Peng
The wide-spread interest in the dynamical property of organic materials under strong states of confinement largely began with differential scanning calorimeter (DSC) measurements in the early 90's of the glass transition and heat capacity of glass forming
Sung Kim, Christopher L. Holloway, James R. Baker-Jarvis, Edward Kuester, A D. Scher
In this paper, we present the extraction for effective material parameters for a metamaterial from TE or TM waveguide measurements with generalized sheet transition conditions (GSTCs)used to provide electric and magnetic surface susceptibilities that
Atomic force microscopy (AFM) methods for quantitative measurements of elastic modulus on stiff (>10 GPa) materials typically require tip-sample contact forces in the hundreds of nanonewton to few micronewton range. Such large forces can incur sample
Eric L. Shirley, Joshua J. Kas, J. T. Vinson, Fernando D. Vila, John J. Rehr
Theoretical optical and x-ray spectra of model structures of water and ice are calculated using a many-body perturbation theory, Bethe-Salpeter equation (BSE) approach implemented in the valence- and core-excitation codes AI2NBSE and OCEAN. These codes use
A review on the use of sharp, fixed-profile indenters as materials probes is presented. Indentation is proposed as a simple but powerful methodology for evaluating basic mechanical propertieselastic modulus, hardness, toughness, etc.in all classes of
Andrew Allen, Jeffrey J. Thomas, Hamlin M. Jennings
Alkali-activated slag (AAS) paste was analyzed using small-angle neutron scattering. The scattering response indicates that the microstructure consists of a uniform matrix of hydration product with a high surface area studded with unhydrated cores of slag
Ward L. Johnson, Sudook A. Kim, Christine F. Rivenbark, Satoshi Uda
Maximization of the quality factors Q of langasite (LGS) and langatate (LGT) is necessary for optimal performance of acoustic resonators of these materials in frequency-control and high-temperature sensing applications. In this report, measurements and
The International Technology Roadmap for Semiconductors (ITRS) Emerging Research Materials (ERM) and Emerging Research Devices (ERD) Technology Workgroups have identified materials and devices that could enable continued increases in the density and
Timothy Weeks, Joseph D. McColskey, Mark D. Richards, Yong-Yi Wang, Zhou Honggang, Ming Liu, W. R. Tyson, James Gianetto, Marie A. Quintana, V. B. Rajan
Najib Cheggour, Xifeng Lu, T G. Holesinger, Theodore C. Stauffer, J Jiang, Loren F. Goodrich
A reversible strain effect on transport critical current I c was found in Bi 2Sr 2CaCu 2O 8+x (Bi-2212) high-temperature superconducting round wires. I c showed unambiguous reversibility at 4 K and 16 T up to an irreversible strain limit of about 0.3 % in
Till Gruendling, Christopher Barner-Kowollik, William E. Wallace, Charles M. Guttman, Anthony J. Kearsley
An overview is given of some new techniques in quantitative composition and molecular mass distribution measurement of synthetic polymers by mass spectrometry. New concepts in data analysis, including peak picking and integration, are also described.
Carbon materials typically have a high density of unpaired electronic spins but the exact nature of the defect sites that give rise to their magnetic properties are not yet well understood. In this work, the paramagnetic interactions between the unpaired
Three fundamental mechanical properties of supported glassy polystyrene films with thickness ranging from 250 nm to 9 nm were quantitatively determined by a recently developed wrinkling-cracking method. Films below about 40 nm showed a decrease in both