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Gabrielle G. Long, Andrew J. Allen, David R. Black, H E. Burdette, Daniel A. Fischer, R D. Spal, Joseph C. Woicik
Synchrotron Radiation Facilities, supported by the Materials Science and Engineering Laboratory of the National Institute of Standards and Technology, include beam stations at the National Synchrotron Light Source at Brookhaven National Laboratory and at
Charles E. Bouldin, June E. Sims, Howard Hung, J J. Rehr, A L. Ankudinov
Modeling x-ray absorption near edge structure (XANES) requires computationally intensive calculations. We show that parallel processing reduces the time required for XANES calculations by a factor of up to 50 over desktop computers. Parallel processing is
U Paik, J P. Kim, Y S. Yung, T Katoh, Jinkyoo Park, Vincent A. Hackley
As a silica slurry for interlayer dielectric CMP is prepared in the alkaline region to accelerate the chemical corrosion process of plasma enhanced tetraethylorthosilicate (PETEOS), Si is dissolved to the point where it will adversely affect the colloidal
The annual meeting of the American Crystallographic Association was held in Los Angeles, California, July 2126, 2001. The scientific sessions and the exhibit show were held in the Westin Bonaventure Hotel in downtownLos Angeles. The meeting was well
Results of Hertzian contact tests investigating the effects of superposed tangential loads on the critical conditions for radial cracking at the under-surfaces of brittle coatings on compliant substrates are reported. It is demonstrated that these effects
Scientists in the Crystallography Section at NIST/NBS made several outstanidng contributions greatly influencing the development and advancement of high pressure x-ray crystallography during the second-half of the 20th century. These milestone achievements
Winnie K. Wong-Ng, H F. McMurdie, C R. Hubbard, Alan D. Mighell
The Research Associateship Program of the Joint Committee on Powder Diffraction -International Centre for Diffraction Data (JCPDS-ICDD, now known as the ICDD) at NBS/NIST was a long-standing (over 35 years), successful, industry-government cooperation. The
The NIST Ceramics Division maintains two materials property databases on the physical, mechanical, thermal, and other properties of high temperature superconductors and structural ceramics. Crystallographic data are featured prominently among the physical
Lawrence H. Robins, J T. Armstrong, Ryna B. Marinenko, Mark D. Vaudin, Charles E. Bouldin, Joseph C. Woicik, Albert J. Paul, W. R. Thurber, K E. Miyano, C A. Parker
The structural and optical properties of indium gallium nitride (InxGa1-xN) films with 0.04
Winnie K. Wong-Ng, Robert S. Roth, Terrell A. Vanderah, H F. McMurdie
Research in phase equilibria and crystallography has been a tradition in the Ceramics Division at NIST since the early thirties. In the early years, effort was concentrated in areas of Portland cement, ceramic glazes and glasses, instrument bearings and
Hydroxyapatite (HAP) belongs to a family of structurally and chemically related, sparingly soluble calcium phosphate (CP) salts [1], and is the structural prototype for the principal mineral component of bone and teeth [2]. Well-defined synthetic HAP has
Soluble polymers are key additives for a broad range of industrial and biomedical applications, including advanced ceramics, mineral separations, high performance cement, and bioceramic coatings and composites. Such species find widespread use as
The discretely diffracting aperiodic crystals termed quasicrystals, discovery at NBS in the early 1980s, have led to much interdisciplinary activity involving mainly materials science, physics, mathematics, and crystalography. It led to a new understanding
Winnie K. Wong-Ng, T Siegrist, G DeTitta, L Finger, H Evans, E Gabe, G Enright, J T. Armstrong, M Levenson, Lawrence P. Cook, C R. Hubbard
Through extensive international collaborations, a standard reference material, SRM 1990 (a set of 3500 units of Cr-doped Al2O3, or ruby sphere) for single crystal diffractometer alignment has been certified at NIST after a successful international round
The Versailles Project on Advanced Materials and Standards (VAMAS) was created in 1982 to support trade through international collaboration in pre-standards research in advanced materials. VAMAS has become self-sustaining through Memoranda of Understanding
Fracture mechanics often is applied in fractographic analyses in order to verigy that the correct feature has been identified as the fracture origin. This step has been codified in ASTM Standard C1322-96, Standard Practice for the Characterization of
A new fixture for flexural strength testing was used to evaluate the effects of machining on the flexural strength of a toughened sintered reaction-bonded silicon nitride. Different grinding procedures had various effects upon the flexure strength
P Miranda, Antonia Pajares, F Guiberteau, F Cumbrera, Brian R. Lawn
A flaw statistics analysis is here developed to account for systematic differences between experimentally observed and theoretically predicted critical loads for the initiation of contact-induced radial cracks in brittle coatings on compliant substrates
The objective of this project is to develop international standard test methods for assessing the reliability of ceramic components used in diesel engines and other heavy vehicle propulsion systems. Advanced ceramics such as silicon nitrides offer unique
X-ray diffraction topography has been used to investigate the relationship between sub-surface damage and fracture strength in sapphire modulus of rupture (MOR) bars. The bars were indistinguishable using standard optical characterization techniques, but x
The tensile creep behavior of a gas-pressure-sintered silicon nitride containing silicon carbide, was carbide was characterized at temperatures between 1375 and 1450 C with applied stresses between 50 and 250 Mpa. Individual specimens were tested at fixed
David R. Black, Robert S. Polvani, George D. Quinn
X-ray topography provides a unique view of the surfaces of single-crystal samples, both before and after fracture. The diffraction topograph, which is sensitive to local strain and/or crystallographic orientation, can be used to inspect samples prior to
Keeping with tradition, the 2000 MRS annual meeting again took place in Boston Copely Plaza from November 27 to December 1. The 2000 meeting was well organized and well attended, with a total of 4600 attendees representing industrial, academic, and
D R. McClure, R W. Cayse, S Goodrich, D McCullum, D C. Harris, K Lagerlof, C E. Patty, D H. Platus, Robert S. Polvani, David R. Black
Approximately 1400 4-point flexure specimens were tested at 300 K to 873 K to establish an engineering database for the strength of sapphire. Coupons represented material used for two missile windows and one missile dome. For one window, coupons were
The structure of the Ba 5R 8Zn 4O 21 series (R =lanthanides) was investigated using x-ray Rietveld refinements. The compounds were successfully prepared for R = Eu, Gd, Dy, Ho, Er, Tm, and Yb. For larger R, Ba 5R 8Zn 4O 21 was not stable, and tetragonal