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Eric B. Norrgard, Stephen Eckel, Christopher L. Holloway, Eric L. Shirley
Precision measurements of quantum systems often seek to probe or must account for the interaction with blackbody radiation. Over the past several decades, much attention has been given to AC Stark shifts and stimulated state transfer. For a blackbody in
Eric B. Norrgard, Stephen Eckel, Christopher L. Holloway, Eric L. Shirley
Blackbody radiation (BBR) sources are calculable radiation sources that are frequently used in radiometry, temperature dissemination, and remote sensing. Despite their ubiquity, blackbody sources, have a plethora of systematics (e.g., emissivity
Ryan Snodgrass, Vincent Y. Kotsubo, Joel Ullom, Scott Backhaus
We report temperature profile measurements from a densely instrumented, commercial pulse tube refrigerator. Azimuthal temperature differences of 15 K were measured across its 3 cm diameter regenerator which was operated at cold end temperatures below 10 K
Ryan Snodgrass, Vincent Y. Kotsubo, Joel Ullom, Scott Backhaus
The real fluid properties of helium have a major impact on the thermodynamics of pulse tube and Gifford-McMahon cryocoolers operating below about 30 K. For example, real fluid properties cause the temperature profile in low-temperature regenerator to be
Dania Velliadou, K.A. Tasidou, K.D. Antoniadis, Marc J. Assael, Richard A. Perkins, Marcia L. Huber
This paper presents a new wide-ranging correlation for the viscosity of xenon based on the most recent theoretical calculations and critically evaluated experimental data. The correlation is designed to be used with an existing equation of state, and it is
Dania Velliadou, Marc J. Assael, K.D. Antoniadis, Marcia L. Huber
A new wide-ranging correlation for the thermal conductivity of xenon based on the most recent theoretical calculations and critically evaluated experimental data, is presented. The correlation is designed to be used with a recently published equation of
We use the path-integral Monte Carlo (PIMC) method and state-of-the-art two-body and three-body potentials to calculate the fourth virial coefficient D(T) of 4He and 3He as a function of temperature from 2.6 K to 2000 K. We derive expressions for the
Low-loss nanophotonic resonators have been widely used in fundamental science and applications thanks to their ability to concentrate optical energy. Key for resonator engineering, the total intrinsic loss is easily determined by spectroscopy, however
Jacob Edmond Ricker, Kevin O. Douglass, Jay H. Hendricks, Jack Stone, Sergei Syssoev, Sefer Avdiaj
Optical refractometry techniques can enable realization of both pressure and temperature directly from properties of the gas. For achieving the highest possible accuracy, temperature uniformity across the refractometer must be less than 1 mK. However, the
This report summarizes the results of work performed for US Army GVSC by the National Institute of Standards and Technology (NIST), Applied Chemicals and Materials Division on the development of a computer program for fire-suppressant bottle-filling
Diego J. Perez, Alexander Stange, Richard Lally, Lawrence Barrett, Matthias Imboden, Abhishek Som, David Campbell, Vladimir Aksyuk, David Bishop
In this article, we present a nano-electromechanical system (NEMS) designed to detect changes in the Casimir Energy. The Casimir effect is a result of the appearance of quantum fluctuations in the electromagnetic vacuum. Previous experiments have used nano
Manuel Baumgartner, Ralf Weigel, Ulrich Achatz, Allan H. Harvey, Peter Spichtinger
The potential temperature is a widely used quantity in atmospheric science since it is conserved for air's adiabatic changes of state. Its definition involves the specific heat capacity of dry air, which is traditionally assumed as constant. However, the
Mark McLinden, Christopher J. Seeton, Andy Pearson
The high global warming potential (GWP) of current refrigerants in cooling equipment based on the vapor-compression cycle has triggered a major effort to find and implement more environmentally benign alternatives. Here, we review the basics of the vapor
In this work, entropy scaling as applied to normal alkanes is used to probe the physics of entropy scaling for fluids with internal degrees of freedom. This approach results in the identification of a universal transition in the behavior of the normal
Kinetic isotope fractionation between water vapor and liquid water or ice depends on the ratio of the diffusivities of the isotopic species in air, but there is disagreement as to the values of these ratios and limited information about their temperature
This work describes measurements of the thermal conductivity of three polyol esters pentaerythritol tetrapentanoate (POE5), pentaerythritol tetraheptanoate (POE7), pentaerythritol tetranonanoate (POE9), and a fully qualified lubricant meeting military
Transport coefficients, such as viscosity or diffusion coefficient, show significant dependence on density or temperature near the glass transition. Although several theories have been proposed for explaining this dynamical slowdown, the origin remains to
In order to enable large-scale molecular simulations, algorithms must efficiently utilize multi-core processors that continue to increase in total core count over time with relatively stagnant clock speeds. Although parallelized molecular dynamics (MD)
Ryo Akasaka, Yukihiru Higashi, Naoya Sakoda, Sho Fukuda, Eric Lemmon
The (p, rho, T) behavior of trifluoroethylene (HFO1123) was investigated with the isochoric method. A total of 87 (p, ρ, T) data were obtained along nine isochores (42, 98, 151, 197, 296, 493, 691, 790, and 888 kg · m−3) at temperatures from 300 K to 430 K
Vaccine temperature control failures represent a significant public and private healthcare cost. Vaccines damaged by excessive heat or freezing lose their effectiveness, putting public health at risk. Some vaccine administration programs recommend placing
As we enter the "fourth generation" of refrigerants, we consider the evolution of refrigerant molecules, the ever-changing constraints and regulations that have driven the need to consider new molecules, and the advancements in the tools and property
Christopher Rzepa, Daniel Siderius, Harold Hatch, Vincent K. Shen, Rangarajan Srinivas, Jeetain Mittal
Vast numbers of unstudied hypothetical porous frameworks continue to spark interest in optimizing adsorption and catalytic processes Evaluating the use of such materials depends on the accessibility of thermodynamic metrics such as the free energy which
State-of-the-art superconductor-based cryogenic detector systems are being installed at numerous research facilities worldwide and are achieving world-record sensitivities in a variety of applications. Implementation has been greatly facilitated by closed