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Nathan Mahynski, Sally Jiao, Harold W. Hatch, Marco A. Blanco Medina, Vincent K. Shen
We describe a methodology for extrapolating the structural properties of multicomponent fluids from one thermodynamic state to another. These properties generally include features of a system that may be computed from an individual configuration such as
Molar heat capacities at constant volume (C_v) of dimethyl ether have been measured with an adiabatic calorimeter. Temperatures range from the triple point to 345 K, and pressures up to 35 MPa. Measurements were conducted on liquid in equilibrium with its
Marat Andreev, Juan J. DePablo, Alexandros Chremos, Jack F. Douglas
It is widely appreciated that the addition of salts to water leads to significant changes in the thermodynamic and dynamic properties of these aqueous solutions, which have great significance in biology and manufacturing applications. However, no
Michael Bible, Makfir Sefa, Julia Scherschligt, Zeeshan Ahmed, James A. Fedchak, Hartings Mathew
Metal organic framework materials (MOFs) have been primarily recognized for their ability to promote selective storage of gas molecules. In their as-synthesized (powdered) form, MOFs are not easily processed for use in end-devices where their properties
James A. Fedchak, Julia K. Scherschligt, Daniel S. Barker, Stephen P. Eckel, Alex P. Farrell, Makfir Sefa
Ultra-high vacuum systems must often be constructed of materials with ultra-low outgassing rates to achieve pressure of 10-6 Pa and below. In such a case, any component placed into the ultra-high vacuum system must also be constructed of materials with
The viscosity of 1,1,1-trifluoroethane (R143a) was measured with a piezoelectrically actuated, torsionally vibrating quartz sensor. The measurements extended over a temperature range from 300 K to 440 K with pressures to 68 MPa and covered states from the
Daniel W. Siderius, William P. Krekelberg, Wei-Shan NMN Chiang, Vincent K. Shen, Yun Liu
Using Monte Carlo and molecular dynamics simulations, we examine the adsorption of methane in cylindrical silica mesopores in an effort to understand a possible phase transition of adsorbed methane in MCM-41 and SBA-15 silica that was previously identified
Katharina Moritz, Reiner Kleinrahm, Mark O. McLinden, Markus Richter
For the determination of dew-point densities and pressures of fluid mixtures, a new densimeter has been developed. The new apparatus is based on the well-established two-sinker density measurement principle with the additional capability of quantifying
Rigorous calculation of the Poynting correction, which describes the effect of pressure on the fugacity of a condensed phase, requires time-consuming evaluation of a thermodynamic potential such as the IAPWS-95 formulation for water. Simplifying
We report precise experimental values of the enthalpy of sublimation (∆H_s) of quenched condensed films of neon (Ne), nitrogen (N2), oxygen (O2), argon (Ar), carbon dioxide (CO2), krypton (Kr), xenon (Xe), and water (H2O) vapor using a single consistent
A previous correlation for the melting curve of sulfur hexafluoride (SF6) is inconsistent with the thermodynamic slope at the triple point derived from the Clapeyron equation. It is shown that this is probably due to the previous authors combining an
Chenyang Wen, Xianyang Meng, Marcia L. Huber, Jiangtao Wu
The Paris Agreement on climate change, in which many nations have agreed to limit greenhouse gas emissions, has spurred interest in developing working fluids with low global warming potential (GWP) that can satisfy environmental concerns and have
A wide ranging formulation for the viscosity of methane in the limit of zero density is presented. Using ab initio calculated data of Hellmann et al. from 80 K to 1500 K, the functional form was developed by guided symbolic regression with the constraints
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
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
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
In the previous work, palmitic acid in sebum was used as a chronological marker for age dating of fingerprints, using time-of-flight secondary ion mass spectrometry (ToF-SIMS) to visualize its spreading on the surface. Its diffusivity assuming an infinite
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
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
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 (
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
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
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
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
Marc J. Assael, K.D. Antoniadis, William A. Wakeham, Marcia L. Huber, H. Fukuyama
The available experimental data for the thermal conductivity of liquid bismuth, cobalt, germanium and silicon have been critically examined with the intention of establishing thermal conductivity reference correlations. All experimental data have been