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The dielectric properties of acrylic resin composites filled with BaTiO 3 have been evaluated in the broad frequency range. These materials were used as models to study the dielectric response in polymer composite films for de-coupling capacitance
X-ray standing waves associated with dynamical diffraction in perfect crystals are also present during diffraction in high-quality quasicrystals. The fluorescence observed from quasicrystals while scanning the rocking curve of a particular Bragg reflection
Joy Dunkers, Frederick R. Phelan Jr., D P. Sanders, M J. Everett, William H. Green, Donald L. Hunston, Richard~undefined~undefined~undefined~undefined~undefined Parnas
The Composites Group at the National Institute of Standards and Technology has found optical coherence tomography (OCT) to be a powerful tool for non-destructive characterization of polymer matrix composites. Composites often exhibit superior properties to
hesion at the fiber matrix interface of composite specimens is often ascribed to the following factors (Sharpe and Drzal): (1) mechanical interlocking, (2) physicochemical interactions, (3) chemical bonding, and (4) mechanical deformation of the fiber
T Leung, M Gerstenberg, D J. Lavrich, G Scoles, F Schreiber, G Poirier
Monolayers of 1,6-hexanedithiol [HS(CH 2) 6SH] deposited on Au(111) from the gas phase were characterized by scanning tunneling microscopy (STM), grazing incidence X-ray diffraction (GIXD), and low energy atom diffraction (LEAD). Molecular resolution STM
Terrell A. Vanderah, W Febo, Julia Y. Chan, Robert S. Roth, J. M. Loezos, L D. Rotter, Richard G. Geyer, B A. Reisner, Dennis B. Minor
Subsolidus phase equilibria in the CaO:Al2O3:Nb2O5 system at 1325 C in air have been determined. One ternary phase forms, Ca2AlNbO6, which exhibits a perovskite-related structure with 1:1 or NaCl-type ordering of Al3+ and Nb5+ on the B-sites. Indexed X-ray
Lloyd A. Currie, D Klinedinst, R Burch, N Feltham, R Dorsch
There are twin pressures mounting in U.S. industry for increased utilization of biomass feedstocks and biotechnology in production. The more demanding pressure relates to economic sustainability, that is, because of increased competition globally
T Siegrist, C Svensson, Terrell A. Vanderah, Robert S. Roth
The crystal structure of Ba 11Fe 8Ti 9O 41 was determined using single-crystal and powder X-ray diffraction nethods. This new phase crystallizes in the hexagonal space group P6 3/mmc (No 194) (a=5.7506(3) , c=61.413(2) ; Z=2; Pcalc=5.75 g/cm 3) and
CaTiO 3 has a static dielectric constant that extrapolates to a value greater than 300 at zero temperature. We investigate the origin of this large dielectric response on a microscopic level, using first-principles plane-wave pseudopotential density
Joseph M. Antonucci, Drago Skrtic, A W. Hailer, E D. Eanes
Amorphous calcium phosphate (ACP), an important precursor in the biological formation of hydroxyapatite (HAP), has recently been utilized as a bioactive filler in resin-based dental materials. It was found that, if ACP was stabilized against premature
Fiber-matrix interface strength is known to be a critical factor in controlling the long-term performance of structural composites. This parameter is often obtained by using the average fragment length data generated from the single-fiber fragmentation
Gale A. Holmes, Walter G. McDonough, R C. Peterson, Donald L. Hunston
In this paper the nonlinear viscoelastic response of the diglycidyl ether of bisphenol-A (DGEBA)/meta-phenylenediamine (m-PDA) matrix was correlated with changes in the final fragment distribution. The changes in the final fragment distribution were
Gale A. Holmes, Donald L. Hunston, Walter G. McDonough, R C. Peterson
Two of the critical factors controlling the long-term performance and durability of composites in structural applications is the fiber-matrix interfacial shear strength (IFSS) and the durability of the fiber-matrix interface. The single fiber fragmentation
Joy Dunkers, M J. Everett, D P. Sanders, Donald L. Hunston
The Composites Group at the National Institute of Standards and Technology has found optical coherence tomography (OCT) to be a powerful tool for non-destructive characterization of polymer matrix composites. Composites can be made more cost competitive by
David R. Black, Robert S. Polvani, Kate Medicus, H E. Burdette
X-ray diffraction topography was used to investigate the relationship between sub-surface damage, near-surface microstructure, and fracture strength in a series of sapphire modulus of rupture (MOR) bars which had been fabricated to proof test fabrication
Joy Dunkers, D P. Sanders, Donald L. Hunston, M J. Everett
Resistance to impact damage is extremely important for most composites. Such damage can initiate delamination, one of the most common failure modes in composites.. Because this is such an important failure mode, many studies have tried to develop matrix
Christopher N. McCowan, Thomas A. Siewert, D P. Vigliotti, C M. Wang
Ferrite Numbers (FN) were assigned to blocks of stainless steel that serve as secondary ferrite reference materials (RM 8480 and 8481), and these specimens were placed in our Reference Materials inventory. These reference materials are used to calibrate
Julia Y. Chan, Terrell A. Vanderah, Robert S. Roth, Winnie Wong-Ng, B A. Reisner, Richard G. Geyer
The structure and dielectric properties of bulk ceramics in the xCa2AlNbO6: (1-x)Ca3Nb2O8 system were studied. Ca2AlNbO6 (P21/n, a = 5.3785(1) , b = 5.4158(1) , c = 7.6259(1) , b = 89.93(1)o) is a double perovskite with structure similar to CaTiO3 and
Walter G. McDonough, Joseph M. Antonucci, Gary E. Schumacher, Y Shimada
Mechanical property tests such as the diametral tensile, uniaxial tensile, biaxial flexural, shear, and transverse strength tests are commonly used for assessing the bond that forms between dental composites and dental substrates such as dentin and enamel
Gale A. Holmes, E Feresenbet, E Pohl, Walter G. McDonough, D T. Raghavan, D Thompson
The development of methods to assess adhesion at the fiber-matrix interface in composite materials has been driven primarily by the recognition that the interface or interphase in many composite materials has a profound affect on the onset of failure in
Gale A. Holmes, Donald L. Hunston, Walter G. McDonough, R C. Peterson
One of the critical factors controlling the long-term performance and durability of composites in structural applications is the interfacial shear strength (IFSS). The single fiber composite (SFC) test has been viewed by many as the best test for