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Donald R. Burgess Jr., Jeffrey A. Manion, Robert R. Burrell, Valeri I. Babushok, Michael Hegetschweiler, Gregory T. Linteris
A mechanism for the combustion of the refrigerant R-32 (CH2F2) in air mixtures was developed and validated through comparisons with measured flame speeds for a range of equivalence ratios (0.9 to 1.4) and pressures (1 to 3 bar) using a constant-volume
The knowledge of material phases in chromium (Cr), nickel (Ni) stainless steel alloys is sometimes important during parts and structures fabrication processed with additive manufacturing (AM) technologies. Laser-based powder bed fusion (LPBF) is one of
Carla Martin-Villalba, Alfonso Urquia, Guodong Shao
The Tennessee Eastman process is a typical industrial process that consists of five main process units: a two-phase reactor where an exothermic reaction occurs, a separator, a stripper, a compressor, and a mixer. This is a nonlinear open-loop unstable
John H. Lehman, Christopher S. Yung, Nathan A. Tomlin, Davis R. Conklin, Michelle S. Stephens
It has been shown that coatings comprised of carbon nanotubes are very black; that is, characterized by low reflectance over a broad wavelength range from the visible to far infrared. Arguably there is no other material that is comparable. This is
The kinetics of H atom addition to cyclopentene has been studied with a single pulse shock tube at temperatures of (863 to 1167 K) and pressures of (160 to 370) kPa. Hydrogen atoms were generated with thermal precursors in dilute mixtures of cyclopentene
In this work we describe how to efficiently and reliably calculate $p$-$x$ and $T$-$x$ diagrams for binary mixtures of fluids. The method is based on the use of the Helmholtz energy density as the fundamental thermodynamic potential. Through the use of
Nathan D. Orloff, Jasper A. Drisko, Angela C. Stelson, Charles A. Little, James C. Booth, Jordi Mateu, Christian J. Long
Distributed circuit parameters parameterize the transmission and reflection off a given transmission line in terms of a distributed resistance, inductance, capacitance, and conductance, which are per unit length frequency dependent quantities. While there
Jay H. Hendricks, Patrick F. Egan, Jacob E. Ricker, Jack A. Stone Jr., Kevin O. Douglass, Gregory F. Strouse
A team of NIST scientists is working to fundamentally change the way that the unit of pressure is realized and disseminated, an effort that will lead to the elimination of mercury barometer pressure standards.
Nathan D. Orloff, Song Liu, James C. Booth, Dylan F. Williams, Dominec Schreurs, Bart Nauwelaers, Iija Oclet, Charles A. Little
In this work, we present a new hybrid method for dielectric measurements of nanolitre fluid samples on-wafer. The first part of the hybrid method is a technique which extracts the 4 complex permittivity of the microfluidic channel wall material. 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
William P. Krekelberg, Daniel W. Siderius, Vincent K. Shen, Thomas M. Truskett, Jeffrey R. Errington
Using molecular simulations, we investigate the relationship between pore-averaged and position-dependent self- diffusivity of fluids adsorbed in strongly attractive pores as a function of loading. Previous work [Krekelberg et al., Langmuir 2013, 29, 14527
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
Pengfei Niu, Brian J. Nablo, Kiran Bhadriraju, Darwin Reyes-Hernandez
Here we describe the exact processes occurring between two metallic electrodes when measuring volumetric flow rate by electrical impedance in polydimethylsiloxane (PDMS) microchannel. A considerable fraction of the change in impedance, due to change of
In this study, synchrotron-based in-operando multi-scale X-ray scattering analyses are used to connect the microstructural changes to the phase changes in kaolinite on heating from 30 °C to 1150 °C. Combined ultra-small-angle and small-angle X-ray
The use of wireless technologies within factories demands a comprehensive understanding of the problems and potential solutions associated with the rigors of the manufacturing environment Selection and deployment of wireless networking solutions to
Berc Kalanyan, Junjie Zhao, Heather F. Barton, Brent A. Sperling, Gregory N. Parsons
In situ chemical measurements of solution/surface reactions during metal-organic framework (MOF) thin film growth can provide valuable information about the mechanistic and kinetic aspects of key reaction steps, and allow control over crystal quality and
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 (
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 Mahynski, Jeffrey R. Errington, Vincent K. Shen
We derive a method for extrapolating the grand canonical free energy landscape of a multicomponent fluid system from one temperature to another. Previously, we introduced this statistical mechanical framework for the case where kinetic energy contributions
William P. Krekelberg, Daniel W. Siderius, Vincent K. Shen, Thomas M. Truskett, Jeffrey R. Errington
Using molecular simulations, we investigate how the range of fluid-fluid (adsorbate-adsorbate) interactions and the strength of fluid-solid (adsorbate-adsorbent) interactions impact the strong connection between distinct adsorptive regimes and distinct
Charles A. Little, Nathan D. Orloff, Christian J. Long, James C. Booth
Complex impedance measurements of fluids provide unique electrical information with important applications for chemical and pharmacological synthesis, and medical diagnostics. Many relevant fluids are ionic. During electrical measurement, ions in the fluid
Paul NMN Salipante, Charles A. Little, Steven D Hudson
We report on a jetting flow instability of shear banding worm-like micelle (WLM) solutions in microfluidic channels with rectangular cross-sections over an intermediate volumetric flow regime. Particle tracking methods are used to measure the three
David A. Sheen, Werickson Fortunato de Carvalho Rocha, Katrice A. Lippa, Dan Bearden
Process quality control and reproducibility in emerging measurement fields such as metabolomics is normally assured by interlaboratory comparison testing. As a part of this testing process, spectral features from a spectroscopic method such as nuclear