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An octacalcium phosphate forming cement
No full textThe osteoconductive and possibly osteoinductive characteristics of OCP increased the interest in preparation of bone graft materials that contain OCP in its composition. Calcium phosphate cements (CPCs) were prepared using a mixture of alpha-tricalcium phosphate (alpha-TCP) and dicalcium phosphate anhydrous (DCPA), with alpha-TCP / DCPA molar ratio of 1/1 and distilled water or 0.5 mol/L phosphate aqueous solution (pH = 6.1 +/- 0.1) as the cement liquid. Hardening time was (30 +/- 1) min for the CPC mixed with water and (5 +/- 1) min for the CPC mixed with phosphate solution. Diametral tensile strength (DTS), porosity (P), and phase composition (powder x-ray diffraction) were determined after the hardened specimens had been immersed in a physiological-like solution (PLS) for 1 d, 3 d, and 7 d. In CPC specimens prepared with water, calcium hydroxyapatite (HA) was formed and DTS and P were (9.03 +/- 0.48) MPa and (37.05 +/- 0.20) vol % after 1 d, respectively, and (9.15 +/- 0.45) MPa and (37.24 +/- 0.63) vol % after 3 d, respectively. In CPC specimens prepared with phosphate solution OCP and HA were formed and DTS and P were (4.38 +/- 0.49) MPa and (41.44 +/- 1.25) vol % after 1 d, respectively,(4.38 +/- 0.29) MPa and (42.52 +/- 2.15) vol % after 3 d, respectively, and (4.30 +/- 0.60) MPa and (41.38 +/- 1.65) vol % after 7 d, respectively. For each group DTS and P did not change with PLS immersion time. DTS was significantly higher and P was significantly lower for CPCs prepared with water. HA formation slightly increased with immersion time from 40 mass % after 1 d to 50 mass % after 3 d in CPCs prepared with water. OCP + HA formation increased with immersion time from 30 mass % after 1 d to 35 mass % after 3 d and to 45 mass % after 7 d in CPCs prepared with 0.5 mol/L phosphate solution
Lyle H. Schwartz
No full textLyle H. Schwartz
Inducted: 2010
Citation:
For visionary leadership of the science and engineering of materials at NIST, including world class x-ray and neutron scattering user facilities, and modern computational materials science.
Tenure: 1984-1997
Birth: 1936, Chicago, Illinois
Education:
Northwestern University, BS (Science Engineering), 1959
Northwestern University, PhD (Materials Science), 1964
Positions held:
Director, Materials Science and Engineering Laboratory, 1984-1997
Honors:
Fellow, ASM International (1988)
Presidential Meritorious Executive Rank Award (1990)
Distinguished Alumni Award, Northwestern University (1993)
National Academy of Engineering (1994)
National Materials Advancement Award, Federation of Materials Societies (1994)
Leadership Award, The Minerals, Metals, and Materials Society (1995)
Alpha Sigma Mu Lecturer, ASM and TMS (1995)
Department of Commerce Gold Medal (1996)
Distinguished Lectureship in Materials and Society, ASM and TMS (1998)
Honorary Member, ASM International (2002)
Memberships:
ASM International, Board of Trustees (1989-93), Chair, ASM Materials Education Foundation (2006-08)
The Mining, Metallurgical and Materials Society
Materials Research Society (Councilor, 1995-98)
American Physical Society
Sigma XI
Publications:
More than 95 publications and two books including:
Schwartz, L.H., "Quasi-Crystalline Symmetry", Philosophical Transactions of the Royal Society of London Series a-Mathematical Physical and Engineering Sciences, 322, (1567), 439 (1987)
Schwartz, L.H., “The Materials Research Laboratories: Reviewing the First Twenty-Five Years,” Advancing Materials Research, NAS Press, 35-48 (1987)
Schwartz, L.H. and Cohen, J., Diffraction from Materials (book) 2nd edition, Springer-Verlag (1987)
Good, M.L. and Schwartz, L.H., "Government Initiatives in Advanced Manufacturing Technology", Advanced Materials & Processes, 146, (4), 50-55 (1994)
Schwartz, L. H. "Sustainability: The Materials Role", Metallurgical and Materials Transactions B-Process Metallurgy and Materials Processing Science, 30, (2), 157-170 (1999)
Schwartz, L. H. “Undergraduate Materials Education 2010: Status and Recommendations”, JOM, 62, (3), 34-70 (2010
NIST gas hydrate research database and web dissemination channel
No full textTo facilitate advances in application of technologies pertaining to gas hydrates, a freely available data resource containing experimentally derived information about those materials was developed. This work was performed by the Thermodynamic Research Center (TRC) paralleling a highly successful database of thermodynamic and transport properties of molecular pure compounds and their mixtures. Population of the gas-hydrates database required development of guided data capture (GDC) software designed to convert experimental data and metadata into a well organized electronic format, as well as a relational database schema to accommodate all types of numerical and metadata within the scope of the project. To guarantee utility for the broad gas hydrate research community, TRC worked closely with the Committee on Data for Science and Technology (CODATA) task group for Data on Natural Gas Hydrates, an international data sharing effort, in developing a gas hydrate markup language (GHML). The fruits of these efforts are disseminated through the NIST Sandard Reference Data Program [1] as the Clathrate Hydrate Physical Property Database (SRD #156). A web-based interface for this database, as well as scientific results from the Mallik 2002 Gas Hydrate Production Research Well Program [2], is deployed at http://gashydrates.nist.gov
Assessing differences between results determined according to the guide to the expression of uncertainty in measurement
No full textIn some metrology applications multiple results of measurement for a common measurand are obtained and it is necessary to determine whether the results agree with each other. A result of measurement based on the Guide to the Expression of Uncertainty in Measurement (GUM) consists of a measured value together with its associated standard uncertainty. In the GUM, the measured value is regarded as the expected value and the standard uncertainty is regarded as the standard deviation, both known values, of a state-of-knowledge probability distribution. A state-of-knowledge distribution represented by a result need not be completely known. Then how can one assess the differences between the results based on the GUM? Metrologists have for many years used the Birge chisquare test as 'a rule of thumb to assess the differences between two or more measured values for the same measurand by pretending that the standard uncertainties were the standard deviations of the presumed sampling probability distributions from random variation of the measured values. We point out that this is misuse of the standard uncertainties; the Birge test and the concept of statistical consistency motivated by it do not apply to the results of measurement based on the GUM. In 2008, the International Vocabulary of Metrology, third edition (VIM3) introduced the concept of metrological compatibility. We propose that the concept of metrological compatibility be used to assess the differences between results based on the GUM for the same measurand. A test of the metrological compatibility of two results of measurement does not conflict with a pairwise Birge test of the statistical consistency of the corresponding measured values
Names mentioned in Oral history interview of John (Jack) Wachtman, February 4, 2010 / with David Lide, Edwin Fuller, Sheldon Wiederhorn and Hans Oser
No full textOral history interview of Dr. John Wachtman, who had an active career in the Material Science area of the NBS, the predecessor of NIST. Dr. Wachtman first joined NBS as a bench scientist. Dr. Wachtman spent thirty-two years at NIST starting in 1951
Acid neutralization capacity of a tricalcium silicate-containing calcium phosphate cement as an endodontic material
No full textA calcium phosphate cement (CPC) was shown to have the necessary attributes for endodontic materials except adequate basicity needed for antimicrobial properties. To enhance its basicity, tricalcium silicate (Ca3SiO5), a highly alkaline compound, was added to CPC at a mass fraction of 0.25, 0.5 or 0.75. The basicity, acid neutralization and physical properties of the CPC-Ca3SiO5 composites were investigated. Mineral trioxide aggregate (MTA) was used as the control. The acid neutralizing capacity of the CPC-Ca3SiO5 composites and MTA were measured by titrating the suspensions of ground set samples with a 0.2 mol /L HCl at predetermined pH levels, i.e., 11, 9.0, and 7.4. The setting time of CPC-Ca3SiO5 composites determined by the Gilmore needle method was 40 10 min. Acid neutralizing capacity of CPC depended (p 4 h) and excellent handling properties
(Transcript) Oral history interview of John (Jack) Wachtman, February 4, 2010 / with David Lide, Edwin Fuller, Sheldon Wiederhorn and Hans Oser
No full textOral history interview of Dr. John Wachtman, who had an active career in the Material Science area of the NBS, the predecessor of NIST. Dr. Wachtman first joined NBS as a bench scientist. Dr. Wachtman spent thirty-two years at NIST starting in 1951
CEDRIC J. POWELL
No full textCEDRIC J. POWELL
Inducted: 2010
Citation:
For exceptional scientific and organizational work in establishing the physical basis (and infrastructure) for electron spectroscopies of solids, especially as applied to quantitative surface analysis and surface standards
Tenure: 1962-2006
Birth: 1935; Perth, Australia
Education:
University of Western Australia, BS (Physics), 1956
University of Western Australia, PhD (Physics), 1962
Positions held:
Physicist, Atomic Physics and Optical Physics Divisions, Institute for Basic Standards, 1962-1978
Chief, Surface Science Division, Center for Chemical Physics, 1978-1991
Leader, Surface Spectroscopies and Thin Films Group, Surface and Microanalysis Science Division, 1991-1994
NIST Fellow, Surface and Microanalysis Science Division, 1994-2006
NIST Scientist Emeritus, Surface and Microanalysis Science Division, 2007-Present
Honors:
US Department of Commerce Silver Medal (1983) and Gold Medal (1986)Award of Merit, American Society for Testing and Materials (ASTM) (1988)
Riviere Prize, UK ESCA Users Group (1992)
Creation of Cedric Powell Award by ASTM Committee E-42 on Surface Analysis (1993)
Creation of Powell Prize by the Surface Analysis Society of Japan (1995)
Albert Nerken Award, American Vacuum Society (2001)
Technology Prize, International Union of Vacuum Science, Technique, and Applications (2007)
Memberships:
American Physical Society, American Vacuum Society, American Assn. for the Advancement of Science
ASTM Committee E-42 on Surface Analysis, chairman (1980-85)
Board of Trustees, Gordon Research Conferences (1982-88), chairman (1985-86)
Board of Directors, American Vacuum Society (1988-89)
ISO Technical Committee 201 on Surface Chemical Analysis, chairman (1992-98)
Publications:
Co-editor of 3 books, co-author of 5 NIST databases, and an author of more than 240 publications including:
Powell, C. J., “Contrasting Valence-Band Auger-Electron Spectra for Silver and Aluminum”, Phys. Rev. Letters 30, 1179 (1973)
Powell, C. J., “Attenuation Lengths of Low-energy Electrons in Solids”, Surface Science 44, 29 (1974)
Powell, C. J., “Cross Sections for Ionization of Inner-shell Electrons by Electrons”, Rev. Mod. Phys. 48, 33 (1976)
Powell, C. J. and Seah, M. P., “Precision, Accuracy, and Uncertainty in Quantitative Surface Analyses by Auger-Electron Spectroscopy and X-ray Photoelectron Spectroscopy”, J. Vac. Sci. Technol. A 8, 735 (1990)
Tanuma, S., Powell, C. J., and Penn, D. R., ""Calculations of Electron Inelastic Mean Free Paths. II. Data for 27 Elements over the 50-2000 eV Range,"" Surface and Interface Analysis 17, 911 (1991)
Powell, C. J. and Jablonski, A., “Evaluation of Measured and Calculated Electron Inelastic Mean Free Paths Near Solid Surfaces,” J. Phys. Chem. Ref. Data 28, 19 (1999
Matthew Heyman
No full textMatthew Heyman
Inducted: 2010
Citation:
For three decades of service that helped establish a reputation for integrity and world class results for NBS/NIST laboratory and extramural programs, for pioneering efforts in government openness and transparency before these terms were buzzwords, and for substantially improving NBS/NIST’s stakeholder communications leading to improved visibility and recognition for its programs.
Tenure: 1978-2008
Birth: 1951, New York, NY
Education:
State University of New York at Albany, BA (Environmental Studies and English), 1972
The George Washington University, MA (Science, Technology and Public Policy), 1977
Positions held:
Media Liaison Specialist, Public Information Division, 1978-1979
Chief, Media Liaison, Public Information Division, 1979-1989
Acting Director of Public Affairs, DOC Technology Administration, 1989
Communications Advisor to the DOC Deputy Secretary, 1989-1990
Chief, Public and Business Affairs Division, 1990-2003
Chief of Staff, Office of the Director, 2003-2008
Honors:
US Department of Commerce Silver Medal (1987) and Gold Medal (2005)
Commerce Science and Technology Fellow (2001-2002)
Memberships:
Platelet Disorder Support Association;
Science and Technology Media Professionals;
Science, Technology & Innovation Policy Professionals;
International Government Relations and Public Affairs
Impact:
For exceptional leadership in improving the visibility of NIST research and extramural programs to enhance its focus on better meeting the product, service, and communications needs of its stakeholders. He led an agency-wide change in culture to communicate NBS/NIST research results to the media, Congress, and VIPs as a routine expectation for all. Heyman’s leadership strengthen NIST’s relationships with Congress, industry associations, universities and other groups that depend on the organization for key deliverables and whose support is necessary for the agency’s success. He was a pioneer for government openness and transparency before the concepts were expected as the only acceptable behavior for federal agencies. He played a key role in launching and maintaining three major programs: BNQP, ATP, and MEP from their concept to maturity
Ellen Dowd
No full textEllen Dowd
Inducted: 2010
Citation: For her leadership and technical excellence in the development of and leading the implementation of the Human Resources function at NIST
Tenure: 1967-1973, 1980-2006
Birth: 1945, Carbondale, Pennsylvania
Education:
Dunbarton College of the Holy Cross, BA (History), 1967
Positions held:
Supervisory Personnel Management Specialist, Office of Personnel and Civil Rights, 1980-1991
Human Resources Officer, Human Resources Management Division, 1991-2006
Honors:
U.S. Department of Commerce Silver Medal (1985)
Memberships:
Officer, Dunbarton College of the Holy Cross Alumni Association
Member, National Multiple Sclerosis Society
Impact:
For exceptional leadership in managing the conversion of NIST and the Department of Commerce to the National Finance Center payroll system. NIST was the first Departmental agency to make this change. Ms. Dowd is recognized for assisting in the development of NIST’s personnel demonstration project, established by law in 1986, which later became the NIST Alternative Personnel Management System (APMS). NIST’s APMS covers over 90% of NIST employees today. Through her strategic direction NIST designed a novel alternative personnel management system in cooperation with the U.S. Department of Commerce (DoC) and the Office of Personnel Management (OPM). NIST’s APMS, including pay-banding, streamlined position classification, and performance pay, has been in existence for over 23 years. It is a benchmark for other organizations wishing to develop alternative personnel management systems. Specifically, the Department of Commerce patterned its Commerce Alternative Personnel System (CAPS) after NIST’s system