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A Unique Institution: Chapter Four. Reorientation and Reconstitution, 1958-1964
No full textA Unique Institution: The National Bureau of Standards, 1950-1969 (SP925) by Elio Passaglia chronicles the expansion of National Bureau of Standards (NBS) to Boulder, Colo., and the relocation of the main site from downtown Washington, DC to Gaithersburg, Md. The NBS encountered tremendous challenges during this period. When faced with extreme outside pressure, its technical integrity remained intact
A Unique Institution: Chapter Five. Technological Triumph: Social Turmoil, 1964-1969
No full textA Unique Institution: The National Bureau of Standards, 1950-1969 (SP925) by Elio Passaglia chronicles the expansion of National Bureau of Standards (NBS) to Boulder, Colo., and the relocation of the main site from downtown Washington, DC to Gaithersburg, Md. The NBS encountered tremendous challenges during this period. When faced with extreme outside pressure, its technical integrity remained intact
James P. Menzer
No full textJames P. Menzer
Inducted: 1999
Citation: For administration of NBS accounting activities and fiscal records.
Tenure: 1954 - 1976
Birth: 1922
Death: 1980
Education:
Indiana University, B.S. (Accounting) 1948
University of the District of Columbia, CPA, 1952
Positions held:
Assistant Chief, Internal Audit Staff
Chief, Internal Audit Division
Memberships:
District Society of Certified Public Accountants
American Institute of Accountant
John W. Cahn (1999)
No full textJohn Werner Cahn was a materials scientist at the National Bureau of Standards from 1977-2007. He was awarded the 27th Annual Kyoto Prize in Advanced Technology in 2011 for his outstanding contributions to alloy materials engineering through his establishment of the theory of spinodal decomposition. Image source: NIST Archive
Analyzing the effects of capacitances-to-shield in sample probes on AC quantized Hall resistance measurements
No full textWe analyze the effects of the large capacitances-to-shields existing in all sample probes on measurements of the ac quantized Hall resistance R-H. The object of this analysis is to investigate how these capacitances affect the observed frequency dependence of R-H. Our goal is to see if there is some way to eliminate or minimize this significant frequency dependence, and thereby realize an intrinsic ac quantized Hall resistance standard. Equivalent electrical circuits are used in this analysis, with circuit components consisting of capacitances and leakage resistances to the sample probe shields; inductances and resistances of the sample probe leads; quantized Hall resistances, longitudinal resistances, and voltage generators within the quantum Hall effect device; and multiple connections to the device. We derive exact algebraic equations for the measured R-H values expressed in terms of the circuit components. Only two circuits (with single-series "offset" and quadruple-series connections) appear to meet our desired goals of measuring both R-H and the longitudinal resistance R-x in the same cool-down for both ac and de currents with a one-standard-deviation uncertainty of 10(-8) R-H or less. These two circuits will be further considered in a future paper in which the effects of wire-to-wire capacitances are also included in the analysis
Validation of new instrumentation for isotope dilution mass spectrometric determination of organic serum analytes
No full textA major activity in the 20 year collaboration between the Analytical Chemistry Division at NIST and the College of American Pathologists (CAP) has been the development of highly accurate and precise "definitive" methods for important clinical analytes in human serum. Definitive methods for organic analytes use isotope dilution/gas chromatography/mass spectrometry and require a mass spectrometer capable of making highly precise measurements of the ratio between the ion intensities of a characteristic ion from the analyte of interest and its stable-isotope-labeled analog. Recently the mass spectrometer used for 20 years for definitive method development and measurements was replaced with a modern instrument capable of automated operation, with accompanying gains in convenience and sample throughput. Switching to the new instrument required modifications of measurement protocols, acceptance criteria, and ratio calculations with background corrections to go along with automated instrument operation. Results demonstrated that the two instruments gave comparable results for measurements of both urea and cholesterol in samples from various serum-based Standard Reference Materials [SRMs] and College of American Pathologists materials
Vacuum processing technique for development of primary standard blackbodies
No full textBlackbody sources with nearly unity emittance that are in equilibrium with a pure freezing metal such as gold, silver, or copper are used as primary standard sources in the International Temperature Scale of 1990 (ITS-90). Recently, a facility using radio-frequency induction heating for melting and filling the blackbody crucible with the freeze metal under vacuum conditions was developed at the National Institute of Standards and Technology (NIST). The blackbody development under a vacuum environment eliminated the possibility of contamination of the freeze metal during the process. The induction heating, compared to a resistively heated convection oven, provided faster heating of crucible and resulted in shorter turnaround time of about 7 h to manufacture a blackbody. This paper describes the new facility and its application to the development of fixed-point blackbodies
Conference Report: SECOND PROCESS SPECIFICATION LANGUAGE (PSL) ROUNDTABLE College Park, MD, January 13-14, 1999
No full textDynamic power-conscious routing for MANETs: An initial approach
No full textWe develop an initial dynamic power-concious routing scheme (MPR) that incorporates physical layer and link layer statistics to conserve power, while compensating for the channel conditions and interference environment at the intended receiver. The aim of MPR is to route a packet on a path that will require the least amount of total power expended and for each node to transmit with just enough power to ensure reliable communication. We evaluate the performance of MPR and present our preliminary results