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The second-stage regenerators of pulse tube refrigerators are routinely used to intercept heat in cryogenic systems; however, optimal methods for heat sinking to the regenerator have not been studied in detail. We investigated intermediate cooling methods
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
The second-stage regenerators of pulse tube refrigerators (PTRs) are routinely used to intercept heat loads without disturbing cooling at their base temperatures, often near 4 K. Gifford-McMahon cryocoolers (GMCs) have not yet demonstrated a similar
Paul Heyliger, Clemens Junker, Karsten Meier, Ward L. Johnson
Vibrational modes of unrestrained elastic cylinders of trigonal crystals are studied using Ritz-based polynomial approximations for displacements formulated in rectangular Cartesian coordinates. The selected orientation of the threefold trigonal axis is
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
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
Today's resistance thermometers can routinely measure temperatures with uncertainties of 10 mK to 100 mK over multiple decades of temperatures across almost all facets of modern life. As modern economy continues to evolve past the industrial age, so does
Kehui Gao, Eric W. Lemmon, Andreas Koester, Monika Thol, Jiangtao Wu
Helmholtz energy equations of state with independent variables of temperature and density were developed for n-perfluorobutane, n-perfluoropentane, and n-perfluorohexane based on experimental thermodynamic property data from the literature and simulation
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
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
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
Mingkang Wang, Rui Zhang, Robert Ilic, Yuxiang Liu, Vladimir Aksyuk
All physical oscillators, from optical cavities to mechanical cantilevers, are subject to thermodynamic and quantum perturbations and detection uncertainty, fundamentally limiting how well their resonance frequency can be measured. Many previous studies of
Temperature scales have evolved through many decades to more accurately represent the thermodynamic temperature. This creates challenges for those who study thermophysical properties, because the temperatures used for literature data may not correspond to
We derive properties of self-assembling rings which can template the organization of an arbitrary colloid into any periodic symmetry in two Euclidean dimensions. By viewing this as a tiling problem, we illustrate how the shape and chemical patterning of
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
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
Ian Bell, Stephanie Delage-Santacreu, Hai Hoang, Guillaume Galliero
We propose a simple and generic definition of a demarcation reconciling structural and dynamic frameworks when combined with the entropy scaling framework. This crossover line between gas- and liquid-like behaviors is defined as the curve for which an
Monika Thol, Stefan Herrig, Roland Span, Eric Lemmon
A fundamental equation of state is presented for the calculation of thermodynamic properties of chlorine. It is expressed in terms of the Helmholtz energy with the independent variables temperature and density. Based on the available experimental data from
We describe the quantum phase transition in the N-state chiral clock model in spatial dimension d=1. With couplings chosen to preserve time-reversal and spatial inversion symmetries, such a model, is in the universality class of recent experimental studies
Advancements in residential net-zero energy buildings (NZEBs) could significantly reduce energy use and greenhouse gas emissions. NZEB design considerations broadly categorize into energy infrastructure connections, renewable energy sources, and energy
Jay H. Hendricks, Zeeshan Ahmed, Daniel Barker, Stephen Eckel, James A. Fedchak, Nikolai Klimov, Julia Scherschligt
At the core of the NIST on a Chip (NoAC) program is the idea that measurement technology can be developed to enable metrology to be done "outside the National Metrology Institute" by virtue of deployed and often miniaturized standards (that can also serve
James A. Fedchak, Julia Scherschligt, Sefer Avdiaj, Daniel Barker, Stephen Eckel, Ben Bowers, Scott O'Connell, Perry Henderson
We have measured the water and hydrogen outgassing rates of seven vacuum chambers of identical geometry but constructed of different materials and heat treatments. Chambers of five different materials were tested: 304L, 316L, and 316LN stainless steels