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Comprehensive review and critical evaluation of the half-life of tritium
No full textAs part of the preparation and calibration of three new National Institute of Standards and Technology (NIST) tritiated-water radioactivity Standard Reference Materials (SRMs), we have performed a comprehensive review and critical evaluation of the half-life of tritium (hydrogen-3). Twenty three experimentally-determined values of the half-life of tritium, reported between 1936 and 2000, were found. Six of these values were updated by later values. Two values were limits. Two values were deemed to be outliers. The 13 remaining values were evaluated in several ways. The results are compared with the results of other recent evaluations and all are found to be in good agreement. Our final recommended value for the half-life of tritium is the average of the adopted values from the four most recent evaluations, (4500 +/- 8) d, where 8 d corresponds to one standard uncertainty
Conference Report: NIST WORKSHOP ON LUMINESCENCE STANDARDS FOR CHEMICAL ANALYSIS, Gaithersburg, MD, September 8-9, 1999
No full textImproved near-infrared spectral responsivity scale
No full textA cryogenic radiometer-based system was constructed at the National Institute of Standards and Technology for absolute radiometric measurements to improve detector spectral power responsivity scales in the wavelength range from 900 nm to 1800 nm. In addition to the liquid-helium-cooled cryogenic radiometer, the system consists of a 100 W quartz-tungsten-halogen lamp light source and a 1 m single-grating monochromator for wavelength selection. The system was characterized and the uncertainty in spectral power responsivity measurements evaluated. A variety of photodetectors, including indium gallium arsenide photodiodes (InGaAs), germanium (Ge) photodiodes, and pyroelectric detectors, were subsequently calibrated. Over most of the spectral range, the spectral power responsivity of the photodetectors can be measured with a combined relative standard uncertainty of 0.4 % or less. This is more than a factor of two smaller than our previous capabilities, and represents a significant improvement in the near infrared (NIR) spectral power responsivity scale maintained at NIST. We discuss the characterization of the monochromator-based system and present results of photodetector spectral power responsivity calibrations
Treasure of the Past V: Experimental manufacture of paper for war maps
No full textEarly in world War II, a new map paper was developed that greatly improved the quality and performance of war maps. The National Bureau of Standards cooperated in the development and, subsequently, determined by experimental manufacture how to make the paper from commercially available raw materials. The best results were obtained in experimental manufacture by using fiber furnishes of 100-percent strong bleached sulfate pulps with the addition of melamine-formaldehyde resin to increase the wet strength and titanium dioxide to produce the desired capacity. It was essential that the beating be very carefully controlled to preserve the maximum fiber strength. The most critical requirements from a manufacturing standpoint were very high resistance to tear, high wet tensile strength, high opacity, and good smoothness. A moderate degree of wildness was not objectionable. The data obtained by experiments were applied to initiate the commercial production of the new paper to meet unprecedented tonnage requirements
Commerce Secretary William Daley delivers an address at the National Quality Awards Ceremony
No full textPresident Bill Clinton is seated on stage reacting to remarks. This image is part of the Malcolm Baldrige Portrait File collection. The Malcolm Baldrige File collection contains photographs of the annual national award given by the President of the United States for industrial excellence. The award was named for Secretary of Commerce Malcolm Baldrige who died in 1987. The collection also includes photographs of the Malcolm 'Mac' Baldrige National Oceanic and Atmospheric Administration (NOAA) Ship
Lawrence Bennett
No full textLAWRENCE H. BENNETT
Inducted: 2000
Citation:
For his wide-ranging and productive research in metal physics and nuclear magnetic resonance (NMR), including co-authorship of a 4-volume text on metallic shifts in NMR, and the use of NMR for the first detection of cancer in vivo.
Tenure: 1958 1996
Birth: 1930, Brooklyn, New York
Education:
Brooklyn College, BA (Physics and Mathematics), 1951
University of Maryland, MS (Physics and Electrical Engineering), 1955
Rutgers University, PhD (Physics), 1958
Positions held:
Physicist, Metals Physics Section
Chief, Alloy Physics section
Chief, Magnetic Materials Group
Senior Executive Service (Charter member)
Senior Scientist, Materials Science and Engineering Laboratory
Honors:
U.S. Department of Commerce Gold Medal, 1971
American Society for Metals Burgess Memorial Award, 1975
Elected to Phi Beta Kappa and Sigma Xi
Memberships:
American Physical Society (Fellow)
American Society for Metals (Fellow)
Metallurgical Society (Past Chair, Committee on Alloy Phases)
Institute of Electrical and Electronics Engineers, Magnetics Society
Publications:
Author of over 300 refereed scientific papers; patent on materials for magnetic refrigeration; editor of 11 books and co author of Metallic Shifts in NMR (4 vols.), published as Progress in Materials Science, v. 20, Pergamon, 1977. Made first detection of cancer in vivo by nuclear magnetic resonance (equipment in Smithsonian)
George Birnbaum
No full textGEORGE BIRNBAUM
NBS/NIST: 1946 ‑ 1956; 1975 ‑ 1995
Birth: July 16, 1919, Brooklyn, New York
Education:
Brooklyn College, BA, 1941
George Washington University: MS, 1949; PhD (Physics), 1956
Principal fields:
Nondestructive evaluation and process sensing; interaction induced infrared absorption in compressed fluids
Positions held at NBS/NIST:
Head, Microwave Dielectric Magnetic Group (Boulder)
Chief, Microwave Frequency and Spectroscopy Section (Boulder)
Senior Scientist
Honors:
U.S. Department of Commerce Gold Medal, 1989
Rockwell International Science Center, Distinguished Fellow, 1975
Elected to Sigma Xi
Memberships:
American Physical Society (Fellow)
Institute of Electrical and Electronics Engineers (Fellow)
Publications:
Many technical papers on infrared spectroscopy, collision induced absorption and light scattering, molecular motions and interactions in compressed fluids; one book, Optical Masers, Academic, 1964
Robert S. Roth
No full textROBERT S. ROTH
NBS/NIST: 1951-1991
Birth: August 21, 1926, Chicago, IL
EDUCATION:
Coe College, BA (Geology), 1947
University of Illinois degrees in geology: MS, 1950; PhD, 1951
PRINCIPAL FIELDS:
Phase equilibria; crystal chemistry and crystallography of inorganic solids
POSITIONS HELD AT NBS/NIST:
Supervisory Chemist, Constitution and Microstructure Section, Mineral Products Division
Chief, Solid State Chemistry Section, Ceramics Division
HONORS:
U.S. Department of Commerce: Silver Medal, 1961; Gold Medal, 1986
American Ceramic Society: Sosman Lecture, 1991; John Jepson Medal, 1995
Elected to Sigma Xi
MEMBERSHIPS:
Geological Society of America (Fellow)
Mineralogical Society of America (Fellow)
American Ceramic Society (Fellow)
American Crystallographic Association
Mineral Society of Great Britain and Ireland
Washington Academy of Sciences (Fellow)
PUBLICATIONS:
Over 200 technical papers in the fields of x ray crystallography, crystal chemistry, and phase equilibria of ceramic materials
Nuclear structure and galactic gamma-ray activity
No full textThe observation of galactic gamma lines following the decay of radioactive nuclei provides a direct link between nuclear physics experiments in earth-based laboratories and astrophysical observations with space-based observatories. Two examples are presented to illustrate this interplay: the measurement of the lifetime of Ti-44 to allow an improved determination of the Ti-44 mass of the supernova remnant Cassiopeia A from the observed gamma ray activity and the measurements of excited states in Si-24 to determine the reaction rate of Al-23(p,gamma)Si-24 which might be important for a reduced production of Na-22 in novae
Nuclear structure studies with the inelastic neutron scattering reaction and gamma-ray detection
No full textThe (n,n'gamma) reaction has been used at the University of Kentucky accelerator facility to examine the detailed structure of a number of nuclei. The advantages of this method are reviewed, and recent developments are described. Examples of unique nuclear structure studies that have been carried out with this method are presented