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Thermal conductivity of magnesium oxide from absolute, steady-state measurements
No full textThe thermal conductivity of polycrystalline magnesium oxide has been measured over the temperature range from 400 K to 1300 K using a modified guarded-hot-plate design. Three different thicknesses of specimens having 93 % of theoretical density were tested to verify the operation, accuracy, and reproducibility of our apparatus. The measured thermal conductivity ranges from 30 W.m(-1).K-1 down to 8 W.m(-1).K-1 and has an inverse-temperature functionality. The results agree well with literature values for this material
Development of a bolometer detector system for the NIST high accuracy infrared spectrophotometer
No full textA bolometer detector system was developed for the high accuracy infrared spectrophotometer at the National Institute of Standards and Technology to provide maximum sensitivity, spatial uniformity, and linearity of response covering the entire infrared spectral range. The spatial response variation was measured to be within 0.1 %. The linearity of the detector output was measured over three decades of input power. After applying a simple correction procedure, the detector output was found to deviate less than 0.2 % from linear behavior over this range. The noise equivalent power (NEP) of the bolometer system was 6 x 10(-12) W/root Hz at the frequency of 80 Hz. The detector output 3 dB roll-off frequency was 200 Hz. The detector output was stable to within +/- 0.05 % over a 15 min period. These results demonstrate that the bolometer detector system will serve as an excellent detector for the high accuracy infrared spectrophotometer
Conference Report: International Workshop on Ultrasonic and Dielectric Characterization Techniques for Suspended Particulates
No full textExperimental issues in coherent quantum-state manipulation of trapped atomic ions
No full textMethods for, and limitations to, the generation of entangled states of trapped atomic ions are examined. As much as possible, state manipulations are described in terms of quantum logic operations since the conditional dynamics implicit in quantum logic is central to the creation of entanglement. Keeping with current interest, some experimental issues in the proposal for trapped-ion quantum computation by J. I. Cirac and P.Zoller (University of Innsbruck) are discussed. Several possible decoherence mechanisms are examined and what may be the more important of these are identified. Some potential applications for entangled states of trapped-ions which lie outside the immediate realm of quantum computation are also discussed
Moving particles through a finite element mesh
No full textWe present a new numerical technique for modeling the flow around multiple objects moving in a fluid. The method tracks the dynamic interaction between each particle and the fluid. The movements of the fluid and the object are directly coupled. A background mesh is designed to fit the geometry of the overall domain. The mesh is designed independently of the presence of the particles except in terms of how fine it must be to track particles of a given size. Each particle is represented by a geometric figure that describes its boundary. This figure overlies the mesh. Nodes are added to the mesh where the particle boundaries intersect the background mesh, increasing the number of nodes contained in each element whose boundary is intersected. These additional nodes are then used to describe and track the particle in the numerical scheme. Appropriate element shape functions are defined to approximate the solution on the elements with extra nodes. The particles are moved through the mesh by moving only the overlying nodes defining the particles. The regular finite element grid remains unchanged. In this method, the mesh does not distort as the particles move. Instead, only the placement of particle-defining nodes changes as the particles move. Element shape functions are updated as the nodes move through the elements. This method is especially suited for models of moderate numbers of moderate-size particles, where the details of the fluid-particle coupling are important. Both the complications of creating finite element meshes around appreciable numbers of particles, and extensive remeshing upon movement of the particles are simplified in this method
(Audio Part 4 of 7) Oral history interview of Marilyn E. Jacox, February 11, 1998 / by Karmal Beal
No full textMaryilyn Jacox begins her discussion with her early interest in science, her education in chemistry and physics, her teaching position at the Mellon Institute and her 15 year collaboration with Dick Milligan. She also recalls her work in free radicals at NBS/NIST (including F-atom reactions in solids and H-atom detachment and acetylene), her mandate to build a laboratory in 1962 upon her arrival at NBS, the Arturim Leonardi Prize which she shared with Dick Milligan, and the Infrared Spectroscopy Glidden Conference
Jerome Kruger
No full textJEROME KRUGER
NBS: 1955 ‑ 1983
Birth: February 7, 1927, Atlanta, Georgia
Education:
Georgia Institute of Technology; BS (Chemistry), 1948; MS (Physical Chemistry), 1950 University of Virginia, PhD (Physical Chemistry), 1953
Principal field:
Corrosion science and engineering
Position held at NBS:
Chief, Corrosion Section of the Metallurgy Division
Honors:
U.S. Department of Commerce: Silver Medal, 1962; Gold Medal, 1972
National Association of Corrosion Engineers (NACE) Whitney Award, 1977
Case Western Reserve University Centennial Scholar, 1980
NBS Stratton Award, 1982
Presidential Rank Award for Meritorious Achievement in the Senior Executive Service of the U.S. Government, 1982
British Institute of Corrosion Ulick R. Evans Award, 1991
Electrochemical Society Olin Palladium Medal and Prize, 1995
Jerome Kruger Corrosion Science Award, NACE Baltimore‑Washington Section, First Recipient, 1997
Jerome Kruger Visiting Scholar Program, University of Virginia; First Visiting Scholar, 1999
Memberships:
National Association of Corrosion Engineers (Fellow; Board of Directors)
Electrochemical Society (Honorary Member; Fellow; Board of Directors)
Federation of Materials Society (President)
American Society for Testing and Materials
Washington Academy of Sciences (Fellow)
Metallurgical Society of AIME
Institute of Corrosion (UK) Honorary Fellow
Publications:
Author or co‑author of many scientific and technical publications