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Ray Radebaugh, Peter E. Bradley, Collin J. Coolidge, Ryan J. Lewis, Y.C. Lee
Lightweight and compact microcoolers are needed for advanced, hand-held infrared systems. A temperature of 150 K is adequate for high sensitivity with some of the latest IR detectors, which simplifies the cooling requirements compared to 80 K detectors
The development of detailed chemical kinetic models has proceeded unabated since the pioneering work of Dixon-Lewis and coworkers forty-five years ago. In that time, computational power has increased ten million-fold, and yet, we do not have a consensus on
Vladimir Diky, Sergey Verevkin, Vladimir Emel?yanenko, Olga Dorofeeva
Enthalpy of combustion of highly pure nitromethane and nitrobenzene have been measured with the precise combustion calorimetry. Enthalpies of vaporization for both compounds were collected and evaluated. New internally consistent experimental data set of
William P. Krekelberg, Vincent K. Shen, Daniel W. Siderius, Thomas M. Truskett, Jeffrey R. Errington
We investigate the structural and diffusive dynamics properties of a model fluid in highly-absorptive cylindrical pores. At subcritical temperatures, self diffusion displays three distinct regimes as a function of average pore density ρ: 1) a decrease in
Vladimir Diky, Sergey Verevkin, Vladimir Emel?yanenko, Olga Dorofeeva
Enthalpy of combustion of highly pure nitromethane and nitrobenzene have been measured with the precise combustion calorimetry. Enthalpies of vaporization for both compounds were collected and evaluated. New internally consistent experimental data set of
Ryan J. Lewis, Mu Hong Lin, Yunda Wang, Jill Cooper, Peter E. Bradley, Ray Radebaugh, Marcia L. Huber, Yung-Cheng Lee
Joule-Thomson (J-T) based micro cryogenic coolers (MCCs) are attractive because they can provide the cryogenic temperatures needed for small electronic devices while having a low cost and small volumetric footprint. A compressor is a major part of a
Mark O. McLinden, Andrei F. Kazakov, J. Steven Brown, Piotr A. Domanski
We explore the possibilities for refrigerants having low global warming potential (GWP) by use of two distinct approaches. In a companion paper (Domanski et al., 2013) we evaluate the effect of a refrigerants fundamental thermodynamic parameters on its
Michael A. Lewis, Ryan P. Taylor, Peter E. Bradley, Ray Radebaugh
Modeling with REGEN3.3 has shown that the phase between flow and pressure at the cold end of 4 K regenerators has a large effect on their second-law efficiency. The use of inertance tubes in small 4 K pulse tube cryocoolers have limited phase shifting
The design of systems for operation at cryogenic temperatures requires the use of material properties at these low temperatures. The properties at cryogenic temperatures can be much different than the room-temperature values. In addition, some properties
The vapor-compression cycle for refrigeration near ambient temperature achieves high efficiency because the isenthalpic expansion of the condensed liquid is a rather efficient process. However, temperatures are limited to about 200 K with a single-stage
Vladimir L. Orkin, Victor Khamaganov, E. E. Kasimovskaya, A G. Guschin
Rate constants for the gas phase reactions of OH radicals with three partially halogenated alkanes, CHCl3 (kMC), CHFClCFCl2 (k122a), and CH2CFCl2 (k132c), were measured using a discharge flow electron paramagnetic resonance technique over the temperature
Raina V. Gough, Jason A. Widegren, Thomas J. Bruno
Recent surrogate diesel fuel mixture development identified the need for a multiply-substituted, low cetane number, high molecular mass monocycloalkane component. On the basis of a thermophysical property evaluation and prediction, 1,3,5
Vladimir L. Orkin, Victor Khamaganov, S N. Kozlov, Michael J. Kurylo III
Measurements of the rate constants for the gas phase reactions of OH radicals with bromoform (CHBr3) and epichlorohydrin (C3H5ClO) were performed using a flash photolysis resonance-fluorescence technique over the temperature range 230 K to 370 K. The
Ryan J. Lewis, Yunda Wang, Peter E. Bradley, Marcia L. Huber, Ray Radebaugh, Y. C. Lee
Micro Cryogenic Coolers (MCCs) can achieve very small sizes and high efficiencies when operating with a refrigerant mixture, but micro-scale compressors have a limited pressure output. Four refrigerant mixtures were designed to operate between 0.4 MPa and
Dazhen Gu, James P. Randa, Robert L. Billinger, Dave K. Walker
We report a verification method for noise-temperature (NT) measurements on cryogenic low-noise amplifiers (LNAs) at liquid helium temperature. The method uses a comparison between the individual measurements of the LNA and an attenuator and the joint
Vladimir Diky, Robert D. Chirico, Chris D. Muzny, Andrei F. Kazakov, Kenneth G. Kroenlein, Joe W. Magee, Ilmutdin M. Abdulagatov, Carlos A. Diaz-Tovar, Jeong W. Kang, Rafiqul Gani, Michael D. Frenkel
ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for
Michael A. Lewis, Peter E. Bradley, Ryan P. Taylor, Ray Radebaugh
Recent advances in superconducting electronic systems are requiring larger envelopes for cooling power, efficiency, and operational environments from commercial based cryogenic cooling systems. One such system targeted at meeting these requirements is the
Andrea Comandini, Iftikhar A. Awan, Jeffrey A. Manion
Complementary shock-tube studies at the National Institute of Standards and Technology (NIST) and the University of Illinois at Chicago (UIC) have been used to examine the decomposition reactions of the 1-pentyl radical at temperatures of 833 K to 1130 K
Ryan J. Lewis, Yunda Wang, Mu Hong Lin, Marcia L. Huber, Ray Radebaugh, Yung-Cheng Lee
Micro cryogenic coolers (MCCs) are useful to a number of small electronic devices which require low cooling power. The cooling power of MCCs operating with mixed refrigerants in a Joule-Thompson (J-T) cycle can be calculated based on enthalpy calculations
The isomerization and decomposition reactions of 2-pentyl and 3-pentyl radicals have been studied in a single-pulse shock tube over a temperature range of 973 K to 1121 K and pressures of 120 kPa to 800 kPa. The results represent the first direct study of
Linear compressors are used to drive pulse tube or Stirling cryocoolers, and they can be used as expanders in place of inertance tubes when inertance tubes cannot provide sufficient phase shifts between flow and pressure. Commercial linear compressors
David A. Sheen, Claudette M. Rosado-Reyes, Wing Tsang
Unsaturated hydrocarbons are an important component of hydrocarbon fuels and intermediates in their oxidation. Under rich conditions, H atom attack is one of the principle pathways of the decomposition of these unsaturated compounds. Consequently, it is
The tremendous growth of fluorescence applications in the life and material sciences has proceeded largely without sufficient concern for the reliability and uncertainties related to the characterization and performance validation of fluorescence
John J. Curry, E. G. Estupinan, W. P. Lapatovich, Albert Henins, S. D. Shastri
The total vapor-phase densities of Dy in equilibrium with a DyI$_3$/InI condensate and Tm in equilibrium with a TmI$_3$/TlI condensate have been measured for temperatures between 900 K and 1400 K. The measurements show strong enhancements in rare-earth