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Barry J. Bauer, R C. Hedden, Hae-Jeong Lee, Christopher L. Soles, Da-Wei Liu
Small angle neutron and x-ray scattering (SANS, SAXS) are powerful tools in determination of the pore size and content of nano-porous materials with low dielectric constants (low-k) that are being developed as interlevel dielectrics. Several models have
T J. Haugan, M E. Fowler, J C. Tolliver, Paul N. Barnes, Winnie K. Wong-Ng, Lawrence P. Cook
The effect of chemical composition variations on the flux pinning and physical properties of (Y,Nd)1+xBa2-xCu3O7-d superconductors was studied in powders processed by solid-state reaction and equilibrated in air at 910 C. An extended region of single-phase
Lawrence H. Robins, J T. Armstrong, Ryna B. Marinenko, Albert J. Paul, J G. Pellegrino, Kristine A. Bertness
In an effort to improve the accuracy of photoluminescence (PL)spectroscopy as a composition (Al mole fraction) measurement method forthe Al xGa 1-xAs alloy system, the PL peak emission energy,E PL,peak, was measured at room temperature for a set of MBE
The shapes and structures of grain boundaries formed between the basal (0001) surface of large alumina grains and randomly oriented small alumina grains are shown to depend on the additions of SiO 2, CaO, and MgO. If a sapphire crystal is sintered at 1620
Winnie K. Wong-Ng, W Y. Ching, Y N. Xu, James A. Kaduk, I Shirontani, L Swartzendruber
The new superconductor, orthorhombic MoRuP (o-MoRuP), was prepared under high pressure, and its structure was refined using the X-ray Rietveld technique. The grayish-black sample of o-MoRuP is a superconductor with T c=15.5K and having space group Pnma and
In this paper, we present a recent advance in theoretical understanding of a deforming metal, using a strain percolation model which possibly explains spasmodic, fine slip line burst events occurring in the metal. The model addresses how the additional
The Knoop Hardness of five glasses as measured over a wide range of indentation loads. Hardness decreased with increasing load in accordance with the classic indentation size effect (ISE). At moderate loads, cracking dramatically altered the indentation
Planewave pseudopotential calculations of formation energies for several ordered supercells were used as bases for first principles calculations of the CaCO3 - MgCO3 and CdCO3 - MgCO3 phase diagrams. Calculated phase diagrams are in qualitative to
The influence of cracking upon apparent Knoop hardness was investigated for five glasses. The Knoop hardnesses decreased with increasing load in accordance with the classic indentation size effect (ISE). Cracking commenced at moderate loads and, in three
Y Gu, T Nakamura, L Prchlik, S Sampath, Jay S. Wallace
Properties of a graded material were characterized with a procedure based on an inverse analysis. This inverse analysis procedure utilizes experimental records obtained from instrumented micro-indentation measurements and extracts key properties of
H Boukari, Andrew J. Allen, Gabrielle G. Long, J Ilavsky, Jay S. Wallace, C C. Berndt, H Herman
The microstructures of thick plasma-sprayed yttria-stabilized (8% mass) zirconia deposits have been studied in a series of Porod small-angle neutron scattering (SANS) and multiple small-angle neutron scattering (MSANS) experiments. Three main void
The molecular mass distribution (MMD) that is obtained in synthetic polymer characterization may be biased by preferential desorption/ionization of low mass polymer molecules, preferential ion attachment to larger polymers, or degradation and fragmentation
D S. Park, T W. Roh, B Hockey, Y Takigawa, B D. Han, H D. Kim, Y Yasutomi
The microstructure of silicon nitride with aligned silicon nitride whisker seeds was examined by electron microscopy. Silicon nitride sintered with yttria and alumina showed a core-rim structure. A few grains of the sample sintered with yttria and alumina
The wear behavior of advanced ceramics (alumina, silicon nitride, and silcon carbide) changes as the load or the coefficient of friction is increased. This change is associated with a drastic increase in wear rate at a critical load that depends on the
The ability of the lubricant to protect the increasingly complex diesel engines directly affects engine durability and warranty costs and is becoming increasing costly to validate. This paper presents a novel approach to evaluate lubricant performance in a
The evolution of agglomerate structure during drying of particles from suspension has been studied for a nanocrystalline Y2O3 (8 mol %)-stabilized ZrO2 powder. Agglomerates in drying and dried suspensions were examined at the smallest size scales (100 nm
William E. Wallace, Charles M. Guttman, S D. Hanton
Mass spectrometry is a rapidly evolving measurement technique for synthetic polymers. It holds the promise of providing not only absolute molecular mass distributions but also quantitative end-group and repeat-unit composition, and structural information
Microstructure-based finite element simulations were used to study the thermomechanical behavior of calcite and dolomite marbles. For a given mineral microstructure, thermal stresses and elastic strain energy varied with the single-crystal elastic
Anthony J. Bur, S C. Roth, D W. Baugh, K A. Koppi, M A. Spalding, J Gunderson, W C. Buzanowski
We have used a temperature sensitive fluorescent dye, doped into polycarbonate, to monitor the true resin temperature during extrusion processing. The fluorescent dye, perylene, was doped into the polycarbonate at very low concentration. We apply this
W Lijun, H J. Wiesmann, A R. Moodenbaugh, Daniel A. Fischer, Y Zhu, M Suenaga
ria has been widely studied due to its applications, such as a catalyst in vehicle emissions system and an electrolyte material in solid oxide fuel cells. Recently, it has been reported that CeO2-x nanoparticles exhibit lattice expansion and valence
Stress distributions in multilayers subjected to both residual stresses and external bending are analyzed to derive closed-form analytical solutions. There are always three unknowns to be solved and three equilibrium conditions to be satisfied in the
The modified Wyoming test fixture (ASTM D5379-93) with doubly v-notched specimens was investigated as a mean for determining the in-plane shear modulus and strength of unidirectional hybrid composites. Two types of hybrid systems having different fiber-tow