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Performance Testing of Hydraulic Cements: Measuring Sulfate Resistance
No full textThe sulfate resistance of cements used in the construction industry is traditionally assessed by measuring the expansion of a prism of 280 mm (11inch) length and 25 mm (1 inch) square cross section immersed in a sodium sulfate solution for at least one year. The duration of the experiment limits this test from being used as a performance-based determination of innovative mixtures of cementitious materials. In response to the need for a more rapid test protocol, the National Institute of Standards and Technology (NIST) has developed a new test method that measures the expansion of smaller bars (10 mm x 10 mm x 60 mm) made with neat cement paste. With these bars, similar expansion is achieved in less than 3 months, reducing the test duration by a factor of at least 4. This accelerated test method provides more rapid results consistent with the traditional test procedure, allowing for a shorter decision
time and the screening of more materials
Software to Determine Sphere Center from Terrestrial Laser Scanner Data per ASTM Standard E3125-17
No full textTerrestrial laser scanners (TLSs) are instruments that can measure three-dimensional (3D) coordinates of objects at high speed using a laser, resulting in high-density 3D point cloud data. The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) performed research to support the development of documentary standards within the ASTM E57 committee on 3D imaging systems. This led to the publication of ASTM standard E3125-17 on point-to-point distance performance evaluation of a certain class of 3D imaging systems, which includes some TLSs [1].
The ASTM E3125-17 standard requires the use of sphere targets for most point-to-point length measurements. Spheres are also the preferred targets to register multiple TLS scans and for instrument performance evaluation. This is because the geometry of a sphere appears to be the same regardless of the direction of the scan. However, any error in determining the sphere centers will be propagated as registration errors or show up as instrument errors. It is therefore necessary to ensure that the sphere center obtained from the scan data is as close to its true geometric center as possible to minimize such errors
Effect of Charpy Striker Configuration on Low- and High-Energy NIST Verification Specimens
No full textCharpy machines can be equipped with strikers having two different configurations, corresponding to an edge radius of 2 mm or 8 mm. Both striker types are covered by ASTM E23 and ISO 148-1. The effect of striker type on Charpy absorbed energy has been extensively investigated in the past, and clear evidence has been published showing that when using 8 mm strikers, absorbed energy (KV) tends to increase for specimens with KV ≥ 200 J. In this paper, we investigate how striking edge radius affects certified values and uncertainties for National Institute of Standards and Technology (NIST) low-energy and high-energy verification specimens. Test data from two low-energy and two high-energy Charpy lots, analyzed in a statistically rigorous manner, were somewhat contradictory and led to the decision to separately certify low-energy and high-energy lots for use with 2 mm and 8 mm strikers. This agrees with previous findings by other NIST researchers, who recommended individual certifications for the two strikers at all energy levels
Primary Determination of Particle Number Concentration with Light Obscuration and Dynamic Imaging Particle Counters
No full textAccurate number concentrations of particles in liquid media are needed to assess the quality of water, pharmaceuticals, and other liquids, yet there are limited reference materials or calibration services available with clear traceability to the International System of Units. We describe two methods, based on very simple modifications of commercial particle counter instruments, that can provide traceable number concentration measurements. One method used a light obscuration counter. Fitting a model to the data enabled correction for timing and coincidence errors, and gravimetric calibration of the syringe pump gave a traceable determination of measured volume. Other potential biases were diagnosed by analysis of the particle size distribution. The other method used a dynamic imaging particle counter (a flow imaging microscope). The instrument was intentionally configured so that each particle passing through the flow cell was imaged multiple times. Following the particle image acquisition runs, runs with a rinse solution released and counted microspheres adsorbed to tubing or flow-cell walls. Software assembled the redundant particle images into tracks, and the total number of tracks was assigned as the number of particles counted. Both light obscuration and dynamic imaging methods, when applied to polystyrene microspheres of approximately 4 mu m diameter, achieved expanded uncertainties (k = 2) of approximately 2 % of number concentration and agreed to within a difference of 1.1 %
Laurie E. Locascio
No full textLAURIE E. LOCASCIO
NBS/NIST: 1986–2017
INDUCTED: 2018
B: 1961 Cumberland, Maryland
EDUCATION:
James Madison University, BS (Chemistry), 1983
University of Utah, MS (Bioengineering), 1986
University of Maryland at Baltimore, PhD (Toxicology), 1999
CITATION:
For outstanding contributions as a scientist/engineer making significant advances in the fields of analytical chemistry and bioengineering and as an administrator who inspired others through her leadership of NIST’s scientific and technical mission-focused laboratory programs.
POSITIONS HELD AT NBS/NIST:
Research Biomedical Engineer, Molecular Spectroscopy and Microfluidic Methods Group, Analytical Chemistry Division, Chemical Science and Technology Laboratory (CSTL), 1986-2002
Group Leader, Analytical Sensors and Automation Group, Analytical Chemistry Division, CSTL, 1993-1995
Group Leader and Research Biomedical Engineer, Microanalytical Metrology Group, Analytical Chemistry Division, CSTL, 2002-2006
Chief, Biochemical Science Division, Material Measurement Laboratory, 2006-2012
Director, Material Measurement Laboratory, 2012-2016
Acting Associate Director for Laboratory Programs and Principal Deputy to the NIST Director, 2017
HONORS:
NIST Bronze Medal (1991)
NIST Applied Research Award (1993)
U.S. Department of Commerce Silver Medal (2006)
American Chemical Society Division of Analytical Chemistry Arthur F. Findeis Award (2008)
American Chemical Society Earle B. Barnes Award for Leadership in Chemical Research Management (2017)
Washington Academy of Sciences Special Award in Scientific Leadership (2017)
Fellow, American Chemical Society
Fellow, American Institute for Medical and Biological Engineering
MEMBERSHIPS:
American Chemical Society
American Institute for Medical and Biological Engineering
PUBLICATIONS:
Eleven patents and more than 115 publications including:
Jahn, A., Vreeland, W.N., Gaitan, M., and Locascio, L.E., "Controlled Vesicle Self-Assembly in Microfluidic Channels with Hydrodynamic Focusing", J. Am. Chem. Soc. 126(9), 2674-2675 (2004)
Forry, S.P., Reyes, D.R., Gaitan, M., and Locascio, L.E., "Facilitating the Culture of Mammalian Nerve Cells with Polyelectrolyte Multilayers", Langmuir 22(13), 5770-5775 (2006)
Plant, A.L., Locascio, L.E., May, W.E., and Gallagher, P.D., "Improved Reproducibility by Assuring Confidence in Measurements in Biomedical Research", Nature Methods, 11(9), 895-898 (2014
Bettijoyce Breen Lide
No full textBETTIJOYCE BREEN LIDE
NBS/NIST: 1969–2013
INDUCTED: 2018
B: 1948, Springfield, Massachusetts
EDUCATION:
College of William and Mary, BS (Chemistry), 1969
American University, MS (Technology Management), 1975
CITATION:
For outstanding leadership and contributions in the application of informatics in a broad range of NIST programs, including Standard Reference Data, Advanced Technology, and Health IT Programs.
POSITIONS HELD AT NBS/NIST:
Physical Scientist and Programmer, Group Leader, Data Systems Development Group, Office of Standard Reference Data, 1969-1988
Scientific Assistant to the Director, National Measurement Laboratory, 1988-1989
Program Manager and Competitions Manager, Advanced Technology Program, 1989-2006
Senior Advisor and Program Coordinator, Health Information Technology (Health IT), Information Technology Laboratory, 2005-2013
HONORS:
Phi Kappa Phi Honor Society
NBS Bronze Medal (1983)
NIST George A. Uriano Award (1999 and 2002)
MEMBERSHIPS:
American Chemical Society
CODATA (International Committee on Data for Science and Technology)
ICSTI (International Council for Scientific and Technical Information)
American Medical Informatics Association
American Telemedicine Association
Healthcare Information and Management Systems Society
PUBLICATIONS:
Representative publications and software packages include:
Hilsenrath, J. and Breen, B., OMNIDATA, An Interactive System for Data Retrieval, Statistical and Graphical Analysis, and Data-Base Management - A User's Manual, NBS Handbook 125 (1978)
Molino, B. Breen, "Special Features of NBS’s OMNIDATA System Applicable to the Retrieval, Analysis, and Dissemination of Chemical Data", J. Chem. Inf. Comput. Sci. 20(3), 136 (1980)
Molino, B. Breen, "Tools for the Automated Handling of Evaluated Data", Proceedings of the 9th International CODATA Conference, North-Holland Publishing Company (1985)
Lide, B., "Information Infrastructure for Healthcare", NIST/ATP Program Announcement (1994, 1995, 1997)
Lide, B. and Spivack, R., "Advanced Technology Program’s Information Infrastructure for Healthcare Focused Program: A Brief History", J. Am. Med. Inform. Assoc. 7(6), 559 (2000) also NISTIR 6477 (February 2000)
Brady, K., Sriram, R., Lide, B., and Roberts, K., "Testing the Nation’s Healthcare Information Infrastructure: NIST Perspective", IEEE Computer 45, 50 (2012
Geometry and trigonometry and astronomy, oh my!
No full textNIST researchers used geometry and trigonometry to create these rhomboidal (flattened square) tiles to make up hexagonal detector chips for the Atacama Cosmology Telescope in Chile (https://act.princeton.edu/). These tiles are unique because most integrated circuits are made with tools that use all right angles, meaning the resulting tiles are squares. Why does this matter? Because hexagons collect about 20 percent more data. That means these tiles will make the scope's camera about 20 percent more efficient at collecting light and help it get a better picture of the early universe. (NOTE: While the small tiles are rhombuses or parallelograms, they make it possible for the entire chip to have a hexagon shape.) * For those interested in the mathematical details, the pattern was created by using the following equations: first closed curve: [x(t) = (sin(11pit))3, y(t) = (cos(33pit))3]; second closed curve: [x(t) = (2/3)(sin(30pit))3, y(t) = (2/3)(cos(10pit))3
A Normalized Congruent Matching Area Method for the Correlation of Breech Face Impression Images
No full textThe congruent matching cells (CMC) method was invented at the National Institute of Standards and Technology (NIST) for firearm evidence identification and error rate estimation. The CMC method divides the correlated image pairs into cells and uses four parameters to quantify topography similarity and pattern congruency of the correlated cell pairs in firearm breech face impressions on fired cartridge cases. A preliminary conservative numerical identification criterion of C = 6 CMCs was suggested for identifying images of cartridge cases fired from the same firearm. The CMC method was validated by correlations using both three-dimensional (3D) topography images and two-dimensional (2D) optical images from a set of 40 cartridge cases fired from a firearm set composed of 10 consecutively manufactured pistol slides. However, in the original CMC method, due to the difference in the effective data area of the correlated cells, final CMCs obtained from an image pair presented different data quantity (or validity level), and thus the empirical criterion C = 6 CMCs did not remain optimal for identification when the correlated cell size changed. In this study, a normalized congruent matching area (NCMA) method that considers the difference in the data area in each correlated cell pair was developed. Based on the NCMA method, an optimal range of cell sizes for breech face identification with granular characteristics was determined. A binomial model was used to fit the known nonmatching NCMA probability distribution ΨNCMA, and a beta-binomial model was used to fit the known matching NCMA probability distribution ΦNCMA. An experimental improvement in the normalized
identification criterion C of around 6 % was observed in the validation tests when the cell sizes were in the optimal range
NIST in space
No full textThis novel “NIST on a chip” instrument was launched into space on a satellite from Vandenburg Air Force Base in California on Monday, December 3, 2018. (We’ve placed it on top of a quarter so you can get a sense of just how small this device is!) The chip is part of the Compact Spectral Irradiance Monitor (CSIM), an instrument that will monitor and measure the sun’s radiation for two years to help researchers understand how solar variability affects Earth’s climate. (The mission also is testing the effectiveness of smaller satellites that orbit for shorter lengths of time. The data from CSIM will be compared to data from a larger satellite.) The chips, which consist of carbon nanotubes and metals patterned on silicon wafers, measure light intensity and are smaller, faster, cheaper and equally, if not more, accurate than their predecessors. The chips were made under a recent agreement between NIST and the University of Colorado Boulder's Laboratory for Atmospheric and Space Physics (LASP), which built the CSIM
Kilogram redefinition team with commemorative tattoos.
No full textKilogram redefinition team with commemorative tattoos. Three are permanent. Three are henna. All mark the 2018 redefinition of the kilogram. Starting in May 2019, the kilogram will no longer be based on an artifact kept in a vault in France. Instead, it will be based on a new agreed upon value for the Planck Constant. The vote was the culmination of a years-long international scientific quest for even greater precision. As to the real impact of this change … well, that’s an unknown at this point; however, historically, increasing the precision of a measurement or unit has resulted in some pretty amazing technological advances. (Think GPS, for one.) Find out more about the initiative and the science on our SI Redefinition microsite.Pictured left to right: Stephan Schlamminger, Frank Seifert, Darine El Haddad, Leon Chao, Jon R. Pratt and David B. Newel