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Search Publications by: Zeina J. Kubarych (Fed)

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Displaying 1 - 25 of 38

Final Report on CIPM Key Comparison of Multiples and Submultiples of the Kilogram (CCM.M-K2)

October 12, 2021
Author(s)
L O. Becerra, W Bich, N Bignell, G D. Chapman, J.-H. Chung, Stuart Davidson, M Glaser, A Gosset, Zeina J. Kubarych, W G. Lee, A Ooiwa, P Richard, R Spurny, A Torino, J Verbeek, L Q. Zhang
A key comparison concerning mass determination of five mass standards has been carried out under the auspices of the Comite Consultatif pour a la Mase et les Grandeurs Apparantees (CCM) from March 1998 to March 1999. The nominal values of the mass

Milligram mass metrology using an electrostatic force balance

September 28, 2016
Author(s)
Gordon A. Shaw, Julian Stirling, John A. Kramar, Alexander D. Moses, Patrick J. Abbott, Richard L. Steiner, Andrew D. Koffman, Jon R. Pratt, Zeina J. Kubarych
Although mass is typically defined within the International System of Units (SI) at the Kilogram level, the pending redefinition of the SI provides an opportunity to realize mass at any scale using electrical metrology. We propose the use of an

Results from the Magnetic Suspension Mass Comparator for Vacuum-to-Air Mass Dissemination in Support of the Redefinition of the Kilogram

August 1, 2016
Author(s)
Corey A. Stambaugh, Eric C. Benck, Edward C. Mulhern, Patrick J. Abbott, Zeina J. Kubarych
Experiments to realize the new definition of the kilogram will be carried out in vacuum. NIST has developed a magnetic suspension mass comparator to disseminate the new definition to air. This paper details the current status of the system. This includes

PROGRESS ON MAGNETIC SUSPENSION FOR THE NIST VACUUM-TO-AIR MASS DISSEMINATION SYSTEM

September 3, 2015
Author(s)
Corey A. Stambaugh, Edward C. Mulhern, Eric C. Benck, Zeina J. Kubarych, Patrick J. Abbott
The redefined kilogram will be realized in vacuum and a method will be required to disseminate the standard to air. NIST has been developing a magnetic suspension system for this purpose. This paper discusses the progress to characterize and improve the

A constant from a mass, a mass from a constant

November 9, 2014
Author(s)
Jon R. Pratt, Stephan Schlamminger, David B. Newell, Leon S. Chao, Zeina J. Kubarych, Patrick J. Abbott, Yusi A. Cao, Frank C. Seifert, Darine El Haddad
NIST recently used a watt balance instrument known as NIST-3 to measure the Planck constant in terms of IPK with a relative uncertainty of approximately 45 parts in 10e9. Along the way to this new NIST value of h, the instrument was also employed to

NIST 1-kilonewton sine force calibration system

January 22, 2014
Author(s)
Akobuije D. Chijioke, Ricky L. Seifarth, Zeina J. Kubarych
Many force-measurement applications are of a dynamic nature, and in recent decades there has been much progress in demonstrating and developing dynamic calibration systems for force transducers. The National Institute of Standards and Technology (NIST), U

The Planck constant, watt and vacuum balances, and an evolving Mise en pratique for the kilogram in North America

July 1, 2012
Author(s)
Jon R. Pratt, David B. Newell, Zeina J. Kubarych, Stephan Schlamminger, Darine El Haddad, Ruimin Liu, Edwin R. Williams, Dave Inglis, Barry M. Wood, Carlos Sanchez, Richard Green
We report preparations underway at the National Institute of Standards and Technology (NIST) in the United States and at the National Research Council (NRC) in Canada to support the redefinition of the international system of units (SI) and the development

Calibration of dynamic sensors for noncontact-atomic force microscopy

August 12, 2011
Author(s)
Gordon A. Shaw, Jon R. Pratt, Zeina J. Kubarych
Access to quantitative information on surface forces in noncontact-atomic force microscopy (NC-AFM) requires the accurate calibration of several key sensor parameters. This work outlines a dynamic method for calibrating the spring constant of tuning fork

Vacuum technology considerations for mass metrology

July 1, 2011
Author(s)
Patrick J. Abbott, Zeina J. Kubarych
Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI

Getting Closer to Redefining the Kilogram

October 30, 2009
Author(s)
Zeina J. Kubarych
A redefinition to replace the last remaining artifact based SI unit, the kilogram, may occur as early as 2011. This article presents a short summary of the status of current international efforts focused on the redefinition and the internationally agreed

Linking Air and Vacuum Mass Measurement by Magnetic Levitation

May 12, 2009
Author(s)
Zeina J. Kubarych, Patrick J. Abbott, Edwin R. Williams, Ruimin Liu, Vincent J. Lee, Hung-Kung Liu
This paper describes a new approach to directly link air and vacuum mass measurements using magnetic levitation techniques. This procedure provides direct traceability to national standards, presently defined in air, without requiring the estimate of

Constant Pressure and Vacuum Transporter for 1 kg Mass Standards

September 8, 2008
Author(s)
Vincent J. Lee, Zeina J. Kubarych
This report describes the design and intended use of a constant pressure and vacuum transporter for transferring 1 kg mass standards between different locations and environments without compromising the atmospheric conditions and therefore maintaining

Magnetic Levitation System for the Dissemination of a Non-Artifact Based Kilogram

November 27, 2007
Author(s)
Zeina J. Kubarych, Patrick J. Abbott, Edwin R. Williams, Ruimin Liu, Vincent J. Lee
We describe a new approach to directly link air and vacuum mass measurements. This approach uses magnetic levitation along with vacuum and balance technology to realize vacuum mass measurements. It provides direct traceability to the International

Final Report on CIPM Key Comparison of 1 kg Standards in Stainless Steel (CCM.M-K1)

October 1, 2004
Author(s)
R S. Davis, C Aupetit, L O. Becerra, W Bich, N Bignell, G D. Chapman, J.-H. Chung, J Coarasa, Stuart Davidson, N G. Domostroeva, Kitty Fen, M Glaser, W G. Lee, M Lecollinet, Q Li, R Spurny, J Verbeek, Zeina J. Kubarych, A Ooiwa, A Torino
This report describes a Key Comparison of 1 kg standards in stainless steel undertaken by the Consultative Committee on Mass and Related Quantities (CCM) and piloted by the Bureau International des Poids et Mesures (BIPM). The comparisons were carried ou

Effects of Cleaning on the US Prototype Kilograms

January 1, 2001
Author(s)
Zeina J. Kubarych, R S. Davis
This paper dicusses the stability of national prototype kilograms No. 4 and No. 20, belonging to the United States. Calibration history, changes in mass with respect to time, and effects on mass and surface profiles due to cleaning and washing are

The Kilogram and Measurements of Mass and Force

January 1, 2001
Author(s)
Zeina J. Kubarych, Simone L. Yaniv
This paper describes the facilities, measurement capabilities, and ongoing research activities in the areas of Mass and Force at the National Institute of Standards and Technology (NIST). The first section of the paper is devoted to mass metrology and

Status of Mass Metrology at NIST in 2000

January 1, 2000
Author(s)
Zeina J. Kubarych
This paper summarizes the activities in mass metrology at NIST. It includes a description of the facilities and the procedures used in the dissemination of the mass unit. This paper also discusses the research efforts to understand and characterize the

The Kilogram: Last remaining artifact

April 1, 1999
Author(s)
Zeina J. Kubarych
The unit of mass, the kilogram, is the last remaining basic unit defined by an artifact. Worldwide efforts are underway to replace the artifact-based definition with invariant alternatives. This paper describes briefly the history of the kilogram, the