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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
Iftikhar A. Awan, Donald R. Burgess Jr., Jeffrey A. Manion
The decomposition and intramolecular H-transfer isomerization reactions of the 1 pentyl radical have been studied at temperatures of 900 K to 1050 K and pressures of 0.8 bar to 6 bar using the single pulse shock tube technique and additionally investigated
Peter J. Lowell, Galen C. O'Neil, Jason M. Underwood, Joel N. Ullom
Normal metal - Insulator - Superconductor (NIS) tunnel junctions can be used to selectively remove the hottest elec- trons in the normal metal, thereby causing it to cool. NIS tunnel junctions have already been used to cool lithograph- ically integrated
The formation of ligand-protected transition metal nanoclusters in size-selective syntheses is driven by the inherent properties of the protecting ligands. We have previously reported the selective, monodisperse product formation of phosphine protected Au
The computations reported in this paper were done in conjunction with an experimental study involving single pulse shock tube measurements of the thermal decomposition of three chloroalkanes, and that work is reported in an accompanying preceding paper
Iftikhar A. Awan, Donald R. Burgess Jr., Wing Tsang, Jeffrey A. Manion
Single pulse shock tube studies of the thermal dehydrochlorination reactions (chlorocyclopentane → cyclopentene + HCl) and (chlorocyclohexane → cyclohexene + HCl) at temperatures of 843 to 1021 K and pressures of 1.4 to 2.4 bar have been carried out using
Ryan J. Lewis, Mu Hong Lin, Yunda Wang, Jill Cooper, Peter E. Bradley, Ray Radebaugh, Marcia L. Huber, Yung-Cheng Lee
Joule-Thompson (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
Yunda Wang, Ryan J. Lewis, Mu Hong Lin, Yiwei Yan, Ray Radebaugh, Peter E. Bradley, Yung-Cheng Lee
A heat exchanger (HX) plays an important role in many cryogenic systems. This paper demonstrates a fully integrated fabrication process to make a novel monolithic polyimide micro heat exchanger. The structure of this heat exchanger consists of two parallel
The proposal by NASA to use high temperature superconducting (HTS) generators and motors on future (2035) aircraft for turboelectric propulsion imposes difficult requirements for cryocoolers. Net refrigeration powers of about 5 kW to 10 kW at 50 K to 65 K
Peter E. Bradley, Ray Radebaugh, Ryan J. Lewis, Mu Hong Lin, Yung-Cheng Lee
Previously we demonstrated cryogenic cooling in a Joule-Thomson microcryocooler (MCC) with mixed refrigerants operating at pressure ratios of 16:1 that achieved stable temperatures of 140 K with transient temperatures down to 76 K with precooling of the
Ryan J. Lewis, Yunda Wang, Jill Cooper, Mu Hong Lin, Victor M. Bright, Yung-Cheng Lee, Peter E. Bradley, Ray Radebaugh, Marcia L. Huber
Joule-Thomson micro cryogenic coolers (MCCs) are a preferred approach for small and low power cryocoolers. With the same heat lift, MCC's power input can be only 1/10 of a thermoelectric cooler's input, and MCC's size can be only 1/10 of a Stirling cooler
We derive path-integral expressions for the second and third virial coefficients of monatomic quantum gases. Unlike previous work that considered only Boltzmann statistics, we include exchange effects (Bose-Einstein or Fermi-Dirac statistics). We use state
Claudette M. Rosado-Reyes, Jeffrey A. Manion, Wing Tsang
The reaction of propene(CH3CH=CH2) with hydrogen atoms has been investigated in a heated single-pulsed shock tube at temperature between 929K-1212K and pressures of 1.7bar-3.4bar. Stable products from H atom addition and H abstraction have been identified
Gershon Grossman, Peter E. Bradley, Michael A. Lewis, Ray Radebaugh
This article describes an investigation of the transient behavior of a small (2.0 W at 85 K) Pulse Tube cryocooler operating at 120 Hz with an average pressure of 3.5 MPa, capable of relatively fast cool-down to about 60 K. In a series of experiments, the
Iftikhar A. Awan, William S. McGivern, Wing Tsang, Jeffrey A. Manion
The decomposition and isomerization reactions of the 5-methylhex-1-yl radical (1-5MeH) have been studied at temperatures of 889 K to 1064 K and pressures of 1.6 bar to 2.2 bar using the single pulse shock tube technique. The radical of interest was
Eugene Paulechka, Andrei F. Kazakov, Michael D. Frenkel
Thermophysical properties of two refrigerants (perfluoropropane and 2,3,3,3-tetrafluoropropene) were computed using Monte Carlo method with OPLS-AA (Optimized Potentials for Liquid Simulations All Atoms) forcefield. Original OPLS-AA parameters were
Michael D. Frenkel, Robert D. Chirico, Vladimir Diky, Chris D. Muzny, Andrei F. Kazakov, Joe W. Magee, Ilmutdin M. Abdulagatov, Jeongwon Kang
ThermoData Engine (TDE) is the first and only full-scale software implementation of the dynamic data evaluation concept. The software provides critically evaluated thermochemical and thermophysical property values for pure compounds, binary mixtures, and
Akin Akturk, M. Holloway, S. Potbhare, David J. Gundlach, B Li, Neil Goldsman, M Peckerar, Kin P. Cheung
We have developed compact and physics-based distributed numerical models for cryogenic bulkMOSFET operation down to 20 K to advance simulation and first-pass design of device and circuit operation at low temperatures. To achieve this, we measured and
Mark S. Lowenthal, David M. Bunk, Karen W. Phinney
An isotope-dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS) reference measurement procedure was developed to accurately quantify amino acid concentrations in NIST Standard Reference Material (SRM) 2389a Amino Acids in 0.1 mol/L
Currently, there is a desire to extend or enhance petroleum-derived diesel fuel with biodiesel fuel. Biodiesel fuel is a renewable, biomass-derived fluid that is biodegradable, nontoxic, and a better lubricant compared to petroleum-derived diesel fuels. In
Mu Hong Lin, Peter E. Bradley, Marcia L. Huber, Ryan J. Lewis, Ray Radebaugh, Yung-Cheng Lee
Optimized mixed refrigerants are applied in Joule-Thomson (JT) micro cryogenic coolers (MCC) to enhance efficiency. Mixed refrigerants deliver equivalent refrigeration power with much lower pressure ratio and flow rate compared to pure nitrogen refrigerant