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Displaying 51 - 75 of 444

Physics-based Models for photonic thermometers

December 1, 2022
Author(s)
Zeeshan Ahmed
Resistance thermometry, meticulously developed over the last century, provides a time-tested method for taking temperature measurements. However, fundamental limits to resistance-based approaches along with a desire to reduce the cost of sensor ownership

Role of Non-Temperature-Gradient Power Flow Terms in Low-Temperature Regenerators

December 1, 2022
Author(s)
Ryan Snodgrass, Joel Ullom, Scott Backhaus
The total power flow through cryocooler regenerators is key to their performance because it reduces the cooling available at the cold heat exchanger. At temperatures near 4 K, the real-fluid properties of helium and the finite-heat-capacity of regenerator

Connecting entropy scaling and density scaling

August 17, 2022
Author(s)
Ian Bell, Robin Fingerhut, Jadran Vrabec, Lorenzo Costigliola
It is shown that the residual entropy (entropy minus that of the ideal gas at the same temperature and density) is mostly synonymous with the independent variable of density scaling, identifying a direct link between these two approaches. The residual

Emerging technologies in the field of thermometry

June 2, 2022
Author(s)
Zeeshan Ahmed, Graham Machin, Sergey Dedyulin
The past decade saw the emergence of new temperature sensors that have the potential to disrupt a century-old measurement infrastructure based on resistance thermometry. In this review we present an overview of emerging technologies that are either in the

Experimental observation of thermalisation with noncommuting charges

February 9, 2022
Author(s)
Florian Kranzl, Aleksander Lasek, Manoj Joshi, Amir Kalev, Rainer Blatt, Christian Roos, Nicole Halpern
Quantum simulators have recently enabled experimental observations of quantum many-body systems' internal thermalisation. Often, the global energy and particle number are conserved, and the system is prepared with a well-defined particle number—in a

How Austenitic is a Martensitic Steel Produced by Laser Powder Bed Fusion? A Cautionary Tale

December 2, 2021
Author(s)
Fan Zhang, Mark R. Stoudt, Souzan Hammadi, Carelyn E. Campbell, Eric A. Lass, Maureen E. Williams
Accurate phase fraction analysis is an essential element of microstructural characterization of alloys and often serves as a basis to quantify effects such as heat treatment or mechanical deformation. Additive manufacturing (AM) of metals, due to the

On the virial expansion of model adsorptive systems

November 9, 2021
Author(s)
William P. Krekelberg, Vincent Shen
We investigate super critical adsorptive properties of various model systems of variable fluid- solid attractive strengths using the confined-density virial expansion, with coefficients calculated using the Mayer-sampling Monte Carlo method up to fifth

Separation of Peas and Carrots in Boiling Water

October 27, 2021
Author(s)
Zachary H. Levine
Frozen peas and carrots are commonly available in grocery stores in the United States. The carrots are cut into cubes roughly 8 mm on a side. They are prepared together in water which is brought to a boil. Sometimes peas and carrots which are initially

DETERMINATION OF DISTORTION CORRECTIONS FOR A FIXED LENGTH OPTICAL CAVITY PRESSURE STANDARD

September 30, 2021
Author(s)
Jacob Edmond Ricker, Jay H. Hendricks, Kevin O. Douglass, Sarah White, Sergei Syssoev
Optical gas refractometry has enabled new pressure standards to be developed based on a dual Fixed Length Optical Cavity (FLOC) system. NIST in partnership with MKS Instruments has created a portable FLOC pressure standard based gas refractivity. A key

Acoustic measurement of the triple point of neon TNe and thermodynamic calibration of a transfer standard for accurate cryogenic thermometry

July 9, 2021
Author(s)
Changzhao Pan, Fernando Sparasci, Haiyang Zhang, Pascal Gambette, Mark Plimmer, Dario Imbraguglio, Roberto Maria Gavioso, Michael Moldover, Bo Gao, Laurent Pitre
We used absolute primary acoustic gas thermometry (AGT) to calibrate a Pt-Co resistance thermometer on the thermodynamic temperature scale by measuring the speed of sound in helium at a temperature T* chosen to be near the temperature of the triple point

New International Formulation for the Viscosity of Heavy Water

July 8, 2021
Author(s)
Marc J. Assael, S.A. Monogenidou, Marcia L. Huber, Richard A. Perkins, Jan V. Sengers
The International Association for the Properties of Water and Steam (IAPWS) has recently adopted a new formulation for the thermodynamic properties of heavy water. This manuscript describes the development of a new correlation for the viscosity of heavy
Displaying 51 - 75 of 444
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