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Excerpt from: A Unique Institution The National Bureau of Standards 1950 - 1969
No full textAn excerpt from the NIST history volume "A Unique Institution The National Bureau of Standards 1950 - 1969; " about the Point Pleasant (Silver Bridge) Collapse on Dec. 15, 1967
Crystal structures and reference powder patterns of BaR2ZnO5 (R = La, Nd, Sm, Eu, Gd, Dy, Ho, Y, Er, and Tm)
No full textReference x-ray powder patterns and the crystal structures of the lanthanide compounds, BaR2ZnO5, in which R = La, Nd, Sm, Eu, Gd, Dy, Ho, Y, Er, or Tm, were determined by the x-ray Rietveld refinement technique. A structural trend was confirmed for this series of compounds. The compounds with smaller ionic radii (R = Sm, Eu, Gd, Dy, Ho, Y, Er, or Tm) are isostructural to the orthorhombic "green phase" (BaY2CuO5). The lattice parameters for compounds with R = Tm to Sm range from a = 7.01855(9) Angstrom to 7.20452(14) Angstrom, b = 12.25445 (17) Angstrom to 12.5882(2) Angstrom, and c = 5.6786(14) Angstrom to 5.81218(11) Angstrom, respectively. R is sevenfold coordinated inside a monocapped trigonal prism. These prisms share edges to form wave-like chains parallel to the long b-axis. The BaR2ZnO5 compounds which contain larger size R (La and Nd) crystallize in the tetragonal space group 14/mcm. The lattice parameters are a = 6.90982(10) and c = 11.5977(2) Angstrom for BaLa2ZnO5, and a = 6.75979(5) Angstrom and c = 11.54560(12) Angstrom for BaNd(2)ZnO5. The structure consists of ZnO4 tetrahedra (instead of planar CuO4 groups as found in BaR2CuO5) with 10-fold coordinated bicapped square prismatic Ba and 8-fold coordinated bicapped trigonal prismatic R ions between them. The reference x-ray powder patterns will be submitted to the Powder Diffraction File (PDF)
A Unique Institution: The National Bureau of Standards, 1950-1969 (Index)
No full textA Unique Institution: The National Bureau of Standards, 1950-1969 (SP925) by Elio Passaglia chronicles the expansion of National Bureau of Standards (NBS) to Boulder, Colo., and the relocation of the main site from downtown Washington, DC to Gaithersburg, Md. The NBS encountered tremendous challenges during this period. When faced with extreme outside pressure, its technical integrity remained intact
A Unique Institution: Chapter Three. Divestiture and Reaffirmation, 1950-1957
No full textA Unique Institution: The National Bureau of Standards, 1950-1969 (SP925) by Elio Passaglia chronicles the expansion of National Bureau of Standards (NBS) to Boulder, Colo., and the relocation of the main site from downtown Washington, DC to Gaithersburg, Md. The NBS encountered tremendous challenges during this period. When faced with extreme outside pressure, its technical integrity remained intact
A Unique Institution: Chapter Two. Testing Can Be Troublesome
No full textA Unique Institution: The National Bureau of Standards, 1950-1969 (SP925) by Elio Passaglia chronicles the expansion of National Bureau of Standards (NBS) to Boulder, Colo., and the relocation of the main site from downtown Washington, DC to Gaithersburg, Md. The NBS encountered tremendous challenges during this period. When faced with extreme outside pressure, its technical integrity remained intact
Randall S. Caswell
No full textRANDALL S. CASWELL
NBS/NIST: 1952 ‑ 1994
Birth: February 27, 1924, Eugene, Oregon
Education:
Massachusetts Institute of Technology: SB, 1947; PhD (Physics), 1951
Principal field:
Physics of ionizing radiation
Positions held at NBS/NIST:
Physicist, Radiation Physics Division
Chief, Neutron Physics Section
Deputy Director, Center for Radiation Research
Chief, Nuclear Radiation Division, Center for Radiation Research
Chief, Ionizing Radiation Division, Physics Laboratory
Post‑retirement: Guest Researcher, Ionizing Radiation Division, Physics Laboratory
Honors:
U.S. Department of Commerce: Silver Medal, 1969; Gold Medal, 1979
NIST Edward Bennett Rosa Award, 1991
Memberships:
American Physical Society (Fellow)
Committee on Interagency Radiation Research and Policy Coordination, Office of Science and Technology Policy (Chairman, Science Panel)
Consultative Committee for Ionizing Radiations (CCEMRI) (Chairman, Section on Neutron Measurements)
National Council on Radiation Protection and Measurements (NCRP) (Member and Honorary Member of Council)
International Commission on Radiation Units and Measurements (ICRU) (Secretary)
Publications:
Many scientific papers; Chairman of Report Committee or Sponsor of numerous reports on radiation research
John W. Cahn (1999)
No full textJohn Werner Cahn was a materials scientist at the National Bureau of Standards from 1977-2007. He was awarded the 27th Annual Kyoto Prize in Advanced Technology in 2011 for his outstanding contributions to alloy materials engineering through his establishment of the theory of spinodal decomposition. Image source: NIST Archive
Measurement of the rheological properties of high performance concrete: State of the art report
No full textThe rheological or flow properties of concrete in general and of high performance concrete (HPC) in particular, are important because many factors such as ease of placement, consolidation, durability, and strength depend on the flow properties. Concrete that is not properly consolidated may have defects, such as honeycombs, air voids, and aggregate segregation. Such an important performance attribute has triggered the design of numerous test methods. Generally, the flow behavior of concrete approximates that of a Bingham fluid. Therefore, at least two parameters, yield stress and viscosity, are necessary to characterize the flow. Nevertheless, most methods measure only one parameter. Predictions of the flow properties of concrete from its composition or from the properties of its components are not easy. No general model exists, although some attempts have been made. This paper gives an overview of the flow properties of a fluid or a suspension, followed by a critical review of the most commonly used concrete rheology tests, particular attention is given to tests that could be used for HPC. Tentative definitions of terms such as workability, consistency, and rheological parameters are provided. An overview of the most promising tests and models for cement paste is given
Douglas L. Franzen
No full textDOUGLAS L. FRANZEN
Inducted: 1999
Citation:
For research on laser sustained plasmas, high power laser pulse calorimetry. and optoelectronics, origination of fiber optic test procedures for the Telecommunications Industries Association, and development of NIST Standard Reference Materials for optical fibers
Tenure: 1970 1997
Birth: 1942, Minneapolis, Minnesota
Education:
University of Minnesota degrees in electrical engineering: BS, 1964; MSEE, 1966; PhD, 1970
Positions held:
NRC/NBS Postdoctoral Research Fellow in Quantum Electronics Division
Electronics Engineer
Group Leader, Fiber and Integrated Optics Group
Honors:
U.S. Department of Commerce: Silver Medal, 1983; Gold Medal, 1988
NBS Bronze Medal, 1981
NIST Applied Research Award, 1988
Director's Award, Nippon Telegraph and Telephone Co, 1987
NIST CEEE Outstanding Paper Award, 1989
Electronic Industries of America Engineering Department Distinguished Contribution Award, 1992
Memberships:
Optica