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Web Thermo Tables - an On-Line Version of the TRC Thermodynamic Tables
No full textIt has long been understood that availability of thermophysical and thermochemical property data is vital to scientific research and industrial design. For over 65 years, the Thermodynamics Research Center (TRC) has been publishing tables of critically evaluated data covering physical and thermodynamic properties of pure compounds, TRC Tables-Hydrocarbons and TRC Tables-Non-Hydrocarbons. Over their long history, the TRC Tables have always been valued as a reputable source of evaluated thermophysical and thermodynamic data. To facilitate more flexible, convenient, and up-to-date access to the data, here, we present the release of the on-line version of the TRC tables, Web Thermo Tables (WTT). Presently, WTT contains data for 7838 compounds and over 950,000 evaluated data points. The tabulated information includes critical properties, vapor pressures and boiling temperatures, phase transition properties, volumetric properties, heat capacities and derived properties, transport properties, reaction state-change properties, as well as index of refraction, surface tension, and speed of sound. Various search options and data plotting capabilities are provided via the Web interface. WTT are distributed through the NIST Standard Reference Data Program [1]
Properties of Calcium Phosphate Cements With Different Tetracalcium Phosphate and Dicalcium Phosphate Anhydrous Molar Ratios
No full textCalcium phosphate cements (CPCs) were prepared using mixtures of tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA), with TTCP/DCPA molar ratios of 1/1, 1/2, or 1/3, with the powder and water as the liquid. Diametral tensile strength (DTS), porosity, and phase composition (powder x-ray diffraction) were determined after the set specimens have been immersed in a physiological-like solution (PLS) for 1 d, 5 d, and 10 d. Cement dissolution rates in an acidified PLS were measured using a dual constant composition method. Setting times ((30 +/- 1) min) were the same for all cements. DTS decreased with decreasing TTCP/DCPA ratio and, in some cases, also decreased with PLS immersion time. Porosity and hydroxyapatite (HA) formation increased with PLS immersion time. Cements with TTCP/DCPA ratios of 1/2 and 1/3, which formed calcium-deficient HA, dissolved more rapidly than the cement with a ratio of 1/1. In conclusion, cements may be prepared with a range of TTCP/DCPA ratios, and those with lower ratio had lower strengths but dissolved more rapidly in acidified PLS
Metrology and standards needs for some categories of medical devices
No full textWith rapid advances in meso, micro- and nano-scale technology devices and electronics, a new generation of advanced medical devices is emerging, which promises medical treatment that is less invasive and more accurate, automated, and effective. We examined the technological and economic status of five categories of medical devices. A set of metrology needs is identified for each of these categories and suggestions are made to address them
DANIEL T. PIERCE
No full textDaniel T. Pierce
Inducted: 2008
Citation: For the development of innovative electron-spin-based measurement methods and their application to significant problems of surface physics and surface magnetism, such as imaging magnetization in nanostructures and measuring the interlayer coupling of magnetic multilayers.
Tenure: 1975-2007
Birth: 1940, Los Angeles, California
Education:
Stanford University, BS (Physics), 1962
Wesleyan University, MA (Physics), 1966
Stanford University, PhD (Applied Physics), 1970
Positions held:
Physicist, (Electron Physics Group, Electron and Optical Physics Division, Physics Laboratory, 1975 - 1994
NIST Fellow, Electron and Optical Physics Division, and Center for Nanoscale Science and Technology, 1994 - 2007
Honors:
Gaede-Langmuir Prize, American Vacuum Society (1994)
William P. Slichter Award (1992)
Department of Commerce Silver Medal (1978) and Gold Medal (1987)
IR 100 Award (1980 and 1985)
NBS E.U. Condon Award (1980)
Washington Academy of Science, Distinguished Achievement in Physical Science Award (1980)
Memberships:
Fellow, American Physical Society
Fellow, American Vacuum Society
Publications:
More than 170 publications and 3 patents including:
Unguris, J., Celotta, R.J., and Pierce, D.T., ‘Observation of Two Different Oscillation Periods in the Exchange Coupling of Fe/Cr/Fe(100)’, Physical Review Letters 67(1), 140-143 (1991)
Falicov, L.’M..’Pierce, D.’T., et al, ‘Surface, Interface and Thin-Film Magnetism,’ Journal of Materials Research 5(6), 1299-1340 (1990)
Pierce, D.’T.,’Celotta, ‘R.’J., et al, ""GaAs Spin Polarized Electron Source,"" Review of Scientific Instruments 51(4), 478-499 (1980)
Stroscio, J.’A.,’ Pierce, D.’T.,’and’Dragoset, R.’A., ‘Homoepitaxial Growth of Iron and a Real Space View of Reflection-High-Energy-Electron Diffraction,’ Physical Review Letters 70(23), 3615-3618 (1993)
US Patent 3,968,376, Source of Spin Polarized Electrons
US Patent 4,760,254, Apparatus and Method for Electron Spin Polarization Detectio
HRATCH G. SEMERJIAN
No full textHRATCH G. SEMERJIAN
Inducted: 2008
Citation: For outstanding contributions as a pioneering research scientist in combustion and laser diagnostics research, and as a visionary leader from the bench to director of the Chemical Science and Technology Laboratory, as well as acting NIST director. His vision and foresight helped clarify the role of metrology and its impact on industrial competitiveness, trade, and quality of life.
Tenure: 1977-2007
Birth: 1943, Istanbul, Turkey
Education:
Robert College (Istanbul), BS (Mechanical Engineering), 1966
Brown University, MS 1968 and PhD (Engineering), 1972
Positions held:
Research Engineer, Office of Energy Conservation, 1977 - 1978
Group Leader, Chemical Process Metrology Division, CCT, 1978 - 1987
Chief, Process Measurements Division, CCT, 1987 - 1992
Acting Deputy Director, Center for Chemical Technology, 1987 - 1988
Director, Chemical Science and Technology Laboratory, 1992 - 2003
Acting Deputy Director, NIST, 1997; Deputy Director, NIST, 2003 - 2006
Acting Director, NIST, 2004-2005; Chief Scientist, NIST, 2006 - 2007
Honors:
US Department of Commerce Silver Medal (1984), Gold Medal (1995)
US Department of Commerce Federal Engineer of the Year (1991)
US Department of Commerce NIST EEO Award (1995)
Elected ASME Fellow (1996)
Brown University Distinguished Engineering Alumni Medal (1997)
Elected to the National Academy of Engineering (2000)
Memberships:
Fellow, American Society of Mechanical Engineers
Council for Chemical Research
President's Council on Sustainable Development
Advisory Board, NRC Canada, Institute for National Measurement Standards
Advisory Board, NMi VSL (Netherlands)
Advisory Board, National Institute of Advanced Industrial Science and Technology (AIST), (Japan)
International Committee of Weights and Measures (CIPM)
Consultative Committee on Amount of Substance (CCQM), CIPM
Publications:
More than 100 publications, including:
Semerjian, H.G., Santoro, R.J., Goulard, R., and Emmerman, P., “Laser Tomography for Temperature Measurements in Flames,” Proc. of Sixth Symposium on Temperature: Its Measurement and Control in Science and Industry, Vol. 5, pp. 649-660, American Institute of Physics, Washington, DC, (1982)
Dobbins, R.A., Santoro, R.J. and Semerjian, H.G., "Analysis of light scattering from soot using optical cross sections for aggregates," 23rd Symp. (Int'l) on Combustion, pp. 1525-1532, The Combustion Institute, Pittsburgh, PA (1990)
Zachariah, M.R., Chin, D., Semerjian, H.G., and Katz, J.L., “Silica Particle Formation in a Counter-flow Diffusion Flame Reactor”, Combustion & Flame, Vol. 78, No.3/4, pp. 287-298 (1989)
Hodges, J.T., Grehan, G., Presser, C., and Semerjian, H.G., “Elastic Scattering from Spheres Under Non-plane-wave Illumination,” Laser Applications in Combustion and Combustion Diagnostics, Ed: L.C. Liou, SPIE Vol. 1862, pp. 294-308 (1993)
Semerjian, H.G. and Beary, E.S., “Impact of Metrology on the Economy and Quality of Life,” Proc. International Symposium on Measurement Standards 2002, Tokyo, Japan (April 2002
Donald R. Johnson
No full textDONALD R. JOHNSON
Inducted: 2008
Citation:
For outstanding research contributions in spectroscopy and astronomy as well as for distinguished managerial leadership exemplified in the creation of the Center for Advanced Research in Biotechnology (CARB) and the establishment of new NIST extramural programs under the Technology Competitiveness Act of 1988.
Tenure: 1967-1993
Birth: 1938, Tacoma, Washington
Education:
University of Puget Sound, BS (Physics), 1960
University of Idaho, MS (Physics), 1962
University of Oklahoma, PhD (Physics), 1967
Positions held:
Physicist, Molecular Spectroscopy Section, Atomic Physics Division, 1967-76
Analyst, Program Office, 1976-78
Deputy Director, National Measurement Laboratory, 1978-83
Director, National Measurement Laboratory, 1983-88
Director, Task Force on Industrial Technology Services, 1987-88
Special Assistant to Undersecretary of Commerce for Technology Policy, 1989-90
Director, Technology Services, 1988-93
Honors:
Fellow, American Physical Society
Arthur S. Fleming Award for Outstanding Service in the Federal Government (1976)
Department of Commerce Silver Medal (1973) and Gold Medal (1977)
Senior Executive Service, Meritorious Executive (1981) and Distinguished Executive (1988)
Department of Commerce Outstanding Volunteer (1990)
Memberships:
American Physical Society Council 8 years; Chair, Langmuir Prize Committee
ASTM Board of Directors 6 years; Committee on Research and Technical Planning
American Society of Mechanical Engineers; Board on Research and Technology Development
Commission of the European Communities; Bureau of Reference Materials Evaluation Group
National Conference of Standards Laboratories
Advisory Board to House Space & Technology Task Force on Technology Policy
Maryland Governor’s Commission on Excellence in Higher Education
Publications:
40 archival scientific papers plus numerous articles on NBS/NIST including:
Johnson, D.R., and Powell, F.X., “Microwave Detection of Thioformaldehyde,” Science, 679-80 (1970)
Johnson, D.R., and Pearson, R., “Molecular Spectroscopy Microwave Region,” Methods of Experimental Physics, 13B, 102-33 (1976)
Johnson, D.R., and Lovas, F.J., “Microwave Detection of the Molecular Transient Methyleneimine,” Chem. Phys. Lett, 15(1), 65-8 (1972)
Clark, F.O., Lovas, F.J., and Johnson, D.R., “Dimethyl Ether in Orion,” Astrophys. J., 229(2, Pt. 1), 553-9 (1979)
Snyder, L.E., Hollis, J.M., Ulich, B.L., Lovas, F.J., Johnson, D.R., and Buhl, “Radio Detection of Interstellar Sulfur Dioxide,” Astrophys. J., 198(2, Pt. 2), L81-L84 (1975)
Snyder, L.E., Lovas, F.J., and Johnson, D.R., “Silicon Monoxide - Detection of Maser Emission from the Second Vibrationally Excited State,” Astrophys. J., 192(2, Pt. 2), L97-L100 (1974
Uncertainty due to finite resolution measurements
No full textWe investigate the influence of finite resolution Oil measurement uncertainty from the perspective of the Guide to the Expression of Uncertainty in Measurement (GUM). Finite resolution in a measurement that is perturbed by Gaussian noise yields a distribution of results that strongly depends on the location of the true value relative to the resolution increment. We show that there is no simple expression relating the standard deviation of the distribution of measurement results to the associated uncertainty at a specified level of confidence. There is, however, an analytic relation between the mean value and the standard deviation of the measurement distribution. We further investigate the conflict between the GUM and ISO 14253-2 regarding the method of evaluating the standard uncertainty due to finite resolution and show that, on average. the GUM method is Superior, but still approximate
Reflective Optical Chopper Used in NIST High-Power Laser Measurements
No full textFor the past ten years, NIST has used high-reflectivity, optical choppers as beamsplitters and attenuators when calibrating the absolute responsivity and response linearity of detectors used with high-power CW lasers. The chopper-based technique has several advantages over the use of wedge-shaped transparent materials (usually crystals) often used as beam splitters in this type of measurement system. We describe the design, operation and calibration of these choppers. A comparison between choppers and transparent wedge beampslitters is also discussed
Methods for Quantifying and Characterizing Errors in Pixel-Based 3D Rendering
No full textWe present methods for measuring errors in the rendering of three-dimensional points, line segments, and polygons in pixel-based computer graphics systems. We present error metrics for each of these three cases. These methods are applied to rendering with OpenGL on two common hardware platforms under several rendering conditions. Results are presented and differences in measured errors are analyzed and characterized. We discuss possible extensions of this error analysis approach to other aspects of the process of generating visual representations of synthetic scenes