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DAVE: A Comprehensive Software Suite for the Reduction, Visualization, and Analysis of Low Energy Neutron Spectroscopic Data
No full textNational user facilities such as the NIST Center for Neutron Research (NCNR) require a significant base of software to treat the data produced by their specialized measurement instruments. There is no universally accepted and used data treatment package for the reduction, visualization, and analysis of inelastic neutron scattering data. However, we believe that the software development approach adopted at the NCNR has some key characteristics that have resulted in a successful software package called DAVE (the Data Analysis and Visualization Environment). It is developed using a high level scientific programming language, and it has been widely adopted in the United States and abroad. In this paper we describe the development approach, elements of the DAVE software suite, its usage and impact, and future directions and opportunities for development
Calcium Fluoride Precipitation and Deposition From 12 mmol/L Fluoride Solutions With Different Calcium Addition Rates
No full textThe effects of different Ca-addition rates on calcium fluoride (CaF2) precipitation and deposition were investigated in 12 mmol/L sodium fluoride solutions to which 0.1 mol/L calcium chloride solution was continuously added at average rates of (5, 7.5, 10, 12.5, 15 or 20) mmol L1 min1. The changes in ionic fluoride and calcium concentrations, as well as turbidity, were continuously recorded by F and Ca electrodes, and a fiber optic based spectrophotometer, respectively. The F concentration decreased and turbidity increased with time indicating precipitation of CaF2. For the systems with Ca-addition rates of (5, 7.5, 10, 12.5, 15, and 20) mmol L1 min1, the 1 min CaF2 depositions in the model substrate (cellulose filter paper, pores 0.2 m) expressed as mean SD of deposited F per substrate surface area were (3.78 0.31, 11.45 0.89, 9.31 0.68, 8.20 0.56, 6.63 0.43, and 2.09 0.28) g/cm2, respectively (n = 10 for each group). The 1-min F depositions did not show positive correlation to Ca-addition rates. The lowest 1-min F deposition was obtained in the systems with the highest Ca-addition rate of 20 mmol L1 min1 for which CaF2 precipitation rate reached the maximum value of 0.31 mmol L1 s1 almost immediately after beginning of reaction (6 s). The largest 1-min F depositions were obtained from the systems with Ca addition rates of (7.5 to 12.5) mmol L1 min1 in which CaF2 precipitation rates continuously increased reaching the maximum values of (0.13 to 0.20) mmol L1 s1 after (18 to 29) s, respectively. The 1-min F depositions were greatly enhanced in comparison with the control F solutions that did not have continuous Ca-addition. This indicates that continuous Ca addition that controls the rate of CaF2 formation could be a critical factor for larger F depositions from F solutions. The efficacy of conventional F mouthrinses could be improved with addition of a substance that continuously releases Ca
New Spherical Gamma-Ray and Neutron Emitting Sources for Testing of Radiation Detection Instruments
No full textThe National Institute of Standards and Technology (NIST) has developed new gamma-ray and neutron emitting sources for testing radiation detection systems. These radioactive sources were developed for testing of detection systems in maritime applications. This required special source characteristics
High Speed Quantum Key Distribution Over Optical Fiber Network System
No full textThe National Institute of Standards and Technology (NIST) has developed a number of complete fiber-based high-speed quantum key distribution (QKD) systems that includes an 850 nm QKD system for a local area network (LAN), a 1310 nm QKD system for a metropolitan area network (MAN), and a 3-node quantum network controlled by a network manager. This paper discusses the key techniques used to implement these systems, which include polarization recovery, noise reduction, frequency up-conversion detection based on a periodically polled lithium nitrate (PPLN) waveguide, custom high-speed data handling boards and quantum network management. Using our quantum network, a QKD secured video surveillance application has been demonstrated. Our intention is to show the feasibility and sophistication of QKD systems based on current technology
Frances Lummis Lloyd
No full textFRANCES LUMMIS LLOYD
Inducted: 2009
Citation: For revolutionizing dc-voltage metrology by fabricating most of the world’s practical 10-volt Josephson-array voltage standards through 1989
Tenure: 1977-1989
Birth: 1923, Honolulu, Territory of Hawaii
Education:
Duke University, BS (Physics), 1946
University of Virginia, MS (Physics), 1948
Positions held:
Physicist, Electromagnetic Technology Division, Center for Electronics and Electrical Engineering (Boulder), 1977-1989
Honors:
U.S. Department of Commerce, Silver Medal (1980) and Gold Medal (1989)
Research and Development Magazine Industrial Research, 100 Award (1986)
Memberships:
American Physical Society
American Association for the Advancement of Science
Publications:
More than 50 publications, including:
Hamilton, C.A., Lloyd, F.L., Chieh, K., and Goeke, K., “A 10 V Josephson Voltage Standard,” IEEE Trans. Instrum. Meas., Vol. IM-38, No. 2, 314-316 (April 1989)
Lloyd, F.L., Hamilton, C.A., Beall, J.A., Go, D., Ono, R.H., and Harris, R.E., “A Josephson Array Standard at 10 Volts,” Electron Device Letters, Vol. EDL-8, No. 10, 449-450 (October 1987)
Hamilton, C.A., Kautz, R. L. Steiner, R.L., and Lloyd, F.L., “A Practical Josephson Voltage Standard at 1 V,” IEEE Electron Device Lett., Vol. EDL-6, No. 12, 623-625 (December 1985)
Hamilton, C.A. and Lloyd, F.L., “A Superconducting 6-bit A/D Converter with Operation to 2 x 109 Samples/Second,” IEEE Elec. Devices Lett., Vol. EDL-1, No. 5, 92-94 (May 1980)
Harris, R.E., Hamilton, C.A., and Lloyd, F.L., “Multiple-Quantum Interference Superconducting Analog-to-Digital Converter,” Appl. Phys. Lett., Vol. 35, 720 (November 1979
A close-up view of a piece of the eyebar that failed and initiated the collapse of the Point Pleasant Bridge (Silver Bridge) on Dec. 15, 1967
No full textA close-up view of a piece of the eyebar that failed and initiated the collapse of the Point Pleasant Bridge (Silver Bridge) on Dec. 15, 1967. This eyebar is part of a display in the National Institute of Standards and Technology (NIST) Museum in Gaithersburg, MD. NIST, (then called the National Bureau of Standards or NBS) was part of the investigation into the cause of the bridge collapse
A Method for Assigning Priorities to United States Measurement System (USMS) Needs: Nano-Electrotechnologies
No full textIn 2006, the National Institute of Standards and Technology conducted an assessment of the U.S. measurement system (USMS), which encompasses all private and public organizations that develop, supply, use, or ensure the validity of measurement results. As part of that assessment, NIST collaborated with Energetics Incorporated to identify and authenticate 723 measurement needs that are barriers to technological innovations. A number of these measurement needs (64) are relevant to accelerating innovation and commercialization of nano-electrotechnologies. In this paper, we apply the taxonomy from a 2008 international survey that established a global consensus of priorities for standards and measurements in nano-electrotechnologies to rank in priority order the relevant 64 USMS-identified measurement needs. This paper presents a method for assigning priorities that is statistically based and represents a global consensus of stakeholders. Such a method is needed because limited resources exist to address the large number of measurement needs in nano-electrotechnologies, and the most critical measurement needs should be addressed first
Procedures for Wavelength Calibration and Spectral Response Correction of CCD Array Spectrometers
No full textThis work describes a procedure for acquiring a spectrum of an analyte over an extended range of wavelengths and validating the wavelength and intensity assignments. To acquire a spectrum over an extended range of wavelengths with a spectrometer with a charge coupled device (CCD) array detector, it is necessary to acquire many partial spectra, each at a different angular position of the grating, and splice the partial spectra into a single extended spectrum. The splicing procedure exposes instrument dependent artifacts. It is demonstrated that by taking a spectrum of a reference irradiance source and making spectral correction, the artifacts exposed by the splicing are removed from the analyte spectrum. This is because the irradiance reference spectrum contains the same artifacts as the analyte spectrum. The artifacts exposed by the splicing depend on the wavelength of the splice; therefore it is important to measure the irradiance reference spectrum for the same range of wavelengths used to measure the spectrum of the analyte solution. In other words, there is no general spectral correction factor which is applicable to spectra taken for different range of wavelengths. The wavelength calibration is also carried out by splicing many partial spectra from a source like a krypton lamp. However the wavelength assignments are not sensitive to the splicing procedure and the same wavelength calibration can be used for spectra acquired over different extended wavelength ranges. The wavelength calibration checks the validity of the setting of the grating angular position, and the assignment of wavelengths to individual pixels on the CCD array detector. The procedure is illustrated by measuring the spectrum of an orange glass and the spectrum of a suspension of microalgae
List of Names Mentioned in Oral history interview of Richard Fields, June 29, 2009 / with Sam Lowe, Jack Rush, Jack Coriell, David Lide, and Hans Oser.
No full textOral history interview of Dr. Richard Fields, formerly with the Metallurgy Division in the Materials Science and Engineering Laboratory (MSEL), National Bureau of Standards (NBS). Dr. Fields first joined NBS as a post doctoral fellow
Richard A. Durst
No full textRichard A. Durst
Inducted: 2009
Citation: For outstanding leadership and personal contributions to the field of analytical electrochemistry, especially in the areas of pH, ion-selective electrodes, and biosensors.
Tenure: 1963-1964; 1966-1990
Birth: 1937, New Rochelle, New York
Education:
University of Rhode Island, BS (Chemistry), 1960
Massachusetts Institute of Technology, PhD (Chemistry), 1963
Positions held:
NRC-NBS Postdoctoral Research Associate, Center for Analytical Chemistry, 1963-1964
Research Chemist, Microchemical Analysis Section, Center for Analytical Chemistry, 1966-1970
Chief, Electrochemical Analysis Section, Center for Analytical Chemistry, 1970-1973
Research Chemist, Air and Water Pollution Analysis Section, Center for Analytical Chemistry, 1974-1978
Scientific Assistant to the Director, Center for Analytical Chemistry, 1978-79
Acting Deputy Director, Center for Analytical Chemistry, 1985-1986; 1988
Group Leader, Organic Electrochemistry/Analytical Sensors, Center for Analytical Chemistry, 1979-1990
Honors:
Sigma Xi-RESA National Lecturer: "Ion-Selective Electrodes in Science, Medicine, and Technology"(1970)
Research and Development Magazine I-R 100 Award (1986)
U.S. Department of Commerce Silver Medal (1987)
NBS Research Advisory Committee (1984-1987), Chairman (1986-1987)
Gordon Research Conference on Bioanalytical Sensors; Organizer and first Chairman (1988)
Gordon Research Conferences: 7 Invited Lectures
IUPAC Commission I.3 (Electrochemistry); Member (1971-1979)
IUPAC Commission V.5 (Electroanalytical Chemistry); Member (1979-1991), Chairman (1989-91)
IUPAC Analytical Chemistry Division; Member (1991-2001)
Memberships:
Elected Member, European Academy of Sciences
Fellow, International Union of Pure & Applied Chemistry
President, Society for Electroanalytical Chemistry
Publications:
More than 160 publications and 10 patents, including:
Durst, Richard, ed, Ion-Selective Electrodes, NBS Special Publication 314 (1969)
Durst, Richard, Standard Reference Materials: Standardization of pH Measurements, NBS Special Publication 260-53 (1975)
Durst, Richard, ed, Blood pH, Gases, and Electrolytes, NBS Special Publication 450 (1976)
Covington, A.K., and Bates, Roger, Durst, Richard, “Definition of pH Scales, Standard Reference Values, Measurement of pH and Related Terminology,” Pure Appl. Chem. 55, 1467-1476 (1983)
Locascio-Brown, L., Plant, A.L., Horvath, V., Durst, R.A., “Liposome Flow Injection Immunoassay: Implications for Sensitivity, Dynamic Range, and Antibody Regeneration,” Anal. Chem. 62, 2587-2593 (1990