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Displaying 276 - 300 of 826

Perspectives for a new realization of the pascal by optical methods

October 24, 2017
Author(s)
Jay H. Hendricks, Karl Jousten, Jack A. Stone Jr., Patrick F. Egan, Tom Rubin, Christof Gaiser, Rene Schodel, James A. Fedchak, Jacob E. Ricker, Jens Fluegge, Stephen P. Eckel, Julia K. Scherschligt, Daniel S. Barker, Kevin O. Douglass, Gregory F. Strouse, Uwe Sterr, Waldimir Sabuga
Since the beginning of measurement of pressure in the 17th century, the unit of pressure has been defined by the relationship of force per unit area. The present state of optical technology now offers the possibility of using a thermodynamic definition

An integrated and automated calibration system for pneumatic piston gauges

October 17, 2017
Author(s)
Yuanchao Yang, Robert G. Driver, John S. Quintavalle, Julia Scherschligt, Katie M. Schlatter, Jacob Edmond Ricker, Gregory F. Strouse, Douglas A. Olson, Jay H. Hendricks
Recently, a transducer-aided crossfloat (TAC) method for pneumatic piston gauges was proposed. The concept is to use a pressure transducer as a very short-term transfer standard between the standard piston gauge and the test one. Different from the

Reference Correlations for the Viscosity and Thermal Conductivity of n-Undecane

September 26, 2017
Author(s)
Marc J. Assael, T.B. Papalas, Marcia L. Huber
This paper presents new wide-ranging correlations for the viscosity and thermal conductivity of n-undecane based on critically evaluated experimental data. The correlations are designed to be used with a recently published equation of state that is valid

Calorimetric Determination of Enthalpies of Vaporization

September 12, 2017
Author(s)
Eugene Paulechka, Dzmitry H. Zaitsau
A review of calorimeters and experimental procedures used for measurement of enthalpies of vaporization for pure liquids is presented. The calorimetric approaches that are illustrated give an insight into direct determination of enthalpies of vaporization

Internal Pressure and Internal Energy of Saturated and Compressed Phases

September 12, 2017
Author(s)
Joe W. Magee, Ilmutdin Abdulagatov, Nikolai Polikhronidi, Rabiyat Batyrova
Following a critical review of the field, a comprehensive analysis is provided of the internal pressure of fluids and fluid mixtures and its determination in a wide range of temperatures and pressures. Further, the physical meaning is discussed of the

Yang-Yang Critical Anomaly

September 12, 2017
Author(s)
Joe W. Magee, Ilmutdin Abdulagatov, Nikolai Polikhronidi, Rabiyat Batyrova
Following a critical review of related research, a method is described to evaluate the Yang-Yang critical anomaly strength function, , from experimental measurements of two-phase liquid ( ) and vapor ( ) isochoric heat capacities and liquid ( ) and vapor (

New measurement of the Boltzmann constant k by acoustic thermometry of helium-4 gas

September 11, 2017
Author(s)
Laurent Pitre, Fernando Sparasci, Michael R. Moldover, Cecile Guianvarch, Catherine Martin, Martin Himbert, Mark Plimmer, James B. Mehl, Giuliano Albo, Bo Gao, Lara Risegari
The SI unit of temperature will soon be redefined in terms of a fixed value of the Boltzmann constant k derived from an ensemble of measurements worldwide. We report on a new determination of k using acoustic thermometry of helium-4 gas in a 3-litre quasi

ThermoData Engine (TDE) Version 10.2 (Pure Compounds, Binary Mixtures, Ternary Mixtures, and Chemical Reactions): NIST Standard Reference Database 103b

August 31, 2017
Author(s)
Vladimir Diky, Chris D. Muzny, Alexander Y. Smolyanitsky, Ala Bazyleva, Robert D. Chirico, Joe W. Magee, Yauheni Paulechka, Andrei F. Kazakov, Scott A. Townsend, Eric W. Lemmon, Michael D. Frenkel, Kenneth G. Kroenlein
The ThermoData Engine is a software expert system implementing the concept of dynamic data evaluation for thermophysical and thermochemical properties of, primarily, organic compounds. This new release provides a substantially expanded database of

Surface interaction parameter measurement of solvated polymers via model end-tethered chains

August 11, 2017
Author(s)
Richard J. Sheridan, Sara V. Orski, Ronald L. Jones, Sushil K. Satija, Kathryn L. Beers
We present a method for the direct measurement of the relative energy of interaction between a solvated polymer and a solid interface. By tethering linear chains covalently to the surface, we ensured the idealized and constant configuration of polymer

A Boltzmann Constant Determination Based on Johnson Noise Thermometry

August 10, 2017
Author(s)
Nathan E. Flowers-Jacobs, Alessio Pollarolo, Kevin J. Coakley, Anna E. Fox, Horst Rogalla, Weston L. Tew, Samuel P. Benz
A value for the Boltzmann constant was measured electronically using an improved version of the Johnson Noise Thermometry (JNT) system at the National Institute of Standards and Technology (NIST), USA. This system is different from prior ones, including
Displaying 276 - 300 of 826