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A recent evaluation of the accuracy of National Physical Laboratory (NPL) primary frequency standard NPL CsF1 gives an overall frequency uncertainty of δŅ/Ņ 0 =
Joseph Achkar, Andreas Bauch, R Dach, R Hlavac, Luca Lorini, Thomas E. Parker, G. Petit, Dirk Piester, P Uhrich, K Szymaniec
Istituto Elettrotecnico Nazionale Galileo Ferraris (IEN), National Institute of Standards and Technology (NIST), National Physical Laboratory (NPL), Laboratoire
Annex H.3 of the Guide to the Expression of Uncertainty in Measurement presents an example of calibration of a thermometer using a linear regression model
Jaroslaw Grobelny, Pradeep N. Namboodiri, Doo-In Kim, Z C. Ying
Adhesion forces between a gold sphere and flat gold substrate are studied using atomic force microscopy in different environments. The pull-off force measured
sed on simple spatial considerations, models to describe the hydration kinetics of portland cement are developed and compared to existing experimental data
CCQM-K13.1 is a Subsequent Key Comparison for Cadmium and Lead in Sediment conducted to provide the opportunity for two NMIs to demonstrate and document
A Key Comparison (CCQM-K31) of the determination of arsenic in a marine shellfish (oyster tissue) was conducted under the auspices of the CCQM Inorganic
The ASTM C150 standard specification for portland cement now permits the addition of up to 5 % limestone filler. While these and much higher levels of limestone
H M. Stapleton, T. Harner, M. Shoeib, Jennifer M. Lynch, Michele M. Schantz, Stefan D. Leigh, Stephen A. Wise
Polybrominated diphenyl ethers (PBDEs) have been measured for the first time in three different indoor dust Standard Reference Materials (SRMs) prepared by the
For decades, biometric technologies were primarily used in law enforcement applications. Currently, they are increasingly being required in multiple public and
We report a microfluidic instrument to rapidly measure the interfacial tension of multi-component immiscible liquids. The measurement principle rests upon the
Since its initial recognition in 1928 and commercialization in 1936, R-22 has been applied in systems ranging from the smallest window air conditioners to the
Although retroviral and LTR-retrotransposon PPTs differ significantly in both their length and sequence, they are accurately removed from (+) RNA and (+) DNA by
Environmental influences, such as ambient moisture, are well known to be detrimental to the adhesion of polymeric materials to metal surfaces. The adhesion loss
Christopher L. Holloway, David A. Hill, Galen H. Koepke, John M. Ladbury
In this paper we present two versions of a threshold metric for the purpose of accessing the effectiveness of a reverberation chamber. One metric is based on
Christopher Stafford, Kristen Roskov, Thomas Epps, Michael J. Fasolka
Thickness is a governing factor in the behavior of films and coatings. To enable the high-throughputanalysis of this parameter in polymer systems, we detail the
T B. Copelen, W Brand, M Gehre, M Groening, HAJ Meijer, Blaza Toman, R. Michael Verkouteren
We present state-of-the-art measurements and data evaluation methods to show that the consistency of carbon isotope ratio measurements can be improved 39 % to
Jeffrey Fong, James J. Filliben, Roland deWit, Richard J. Fields, Barry Bernstein, Pedro V. Marcal
In this paper, we first review the impact of the powerful finite element method (FEM) in structural engineering, and then address the shortcomings of FEM as a
The emission spectrum of neodymium produced by vacuum spark sources was observed in the vacuum ultraviolet on two normal-incidence spectrographs. In an initial
High resolution IR absorption spectra of supersonically cooled ethyl radicals (T rot19 K) have ben obtained in a slit supersonic jet discharge expansion
Understanding many body interactions is a universal challenge in physics that is best approached by studying carefully chosen model systems. One ideal system
Economic tools are needed to help the owners and managers of buildings, industrial facilities, and other critical infrastructure to select cost-effective
Operators acting on a collection of two-level quantum-mechanical systems can be represented by quantum circuits. In this work we develop a decomposition of such