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in subjects: "37 Inorganic, Organic, Physical And Analytical Chemistry"  
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Fast Prediction of HCCI and PCCI Combustion with an Artificial Neural Network-Based Chemical Kinetic Model

Description: We have added the capability to look at in-cylinder fuel distributions using a previously developed ignition model within a fluid mechanics code (KIVA3V) that uses an artificial neural network (ANN) to predict ignition (The combined code: KIVA3V-ANN). KIVA3V-ANN was originally developed and validated for analysis of Homogeneous Charge Compression Ignition (HCCI) combustion, but it is also applicable to the more difficult problem of Premixed Charge Compression Ignition (PCCI) combustion. PCCI co… more
Date: September 26, 2007
Creator: Piggott, W. T.; Aceves, S. M.; Flowers, D. L. & Chen, J. Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Threshold Studies on TNT, Composition B, and C-4 Explosives Using the Steven Impact Test

Description: Steven Impact Tests were performed at low velocity on the explosives TNT, Comp B, and C-4 in attempts to obtain a threshold for reaction. A 76 mm helium driven gas gun was used to accelerate the Steven Test projectiles up to approximately 200 m/s in attempts to react (ignite) the explosive samples. Blast overpressure gauges, acoustic microphones, standard video and high-speed photography were used to characterize the level of any high explosive reaction violence. No bulk reactions were observed… more
Date: September 26, 2005
Creator: Vandersall, K S; Switzer, L L & Garcia, F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Remote measurements of actinide species in aqueous solutions using an optical fiber photoacoustic spectrometer

Description: A photoacoustic spectrometer, equipped with an 85 meter optical fiber, was used to perform absorption measurements of lanthanide and actinide samples, located in a glovebox. The spectrometer was tested using aqueous solutions of praseodymium and americium ions; the sensitivity for remote measurements was found to be similar to that achieved in the laboratory without the fiber. 14 refs., 3 figs.
Date: September 26, 1990
Creator: Russo, R. E. (Lawrence Berkeley Lab., CA (United States)); Robouch, P. B. & Silva, R. J. (Lawrence Livermore National Lab., CA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Direct aromatization of methane. Quarterly technical progress report No. 3, April 1, 1993--June 30, 1993

Description: Construction of quench-reactor has been completed. Gaseous reactants are fed in a downward flow and the quenching medium (water) pumped upward into a concentric reactor housed in a high temperature (1540C) furnace. The furnace has a 24 inch, resistively-heated zone, with an overall length of 38 inches. The gaseous effluent is sampled directly into a gas chromatograph via a sampling valve. The gas chromatographic procedure for analysis of expected products is being developed. Several columns hav… more
Date: September 26, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemical Reaction Dynamics in Nanoscle Environments

Description: The major focus of the research in this program is the study of the behavior of molecular systems confined in nanoscale environments. The goal is to develop a theoretical framework for predicting how chemical reactions occur in nanoscale environments. To achieve this goal we have employed ab initio quantum chemistry, classical dynamics and quantum dynamics methods. Much of the research has focused on the behavior of molecules confined within single-walled carbon nanotubes (SWCNTs). We have also… more
Date: September 26, 2006
Creator: Goldfield, Evelyn M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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APPLICATION OF THE EMBEDDED FIBER OPTIC PROBE IN HIGH EXPLOSIVE DETONATION STUDIES: PBX-9502 AND LX-17

Description: The Embedded Fiber Optic probe directly measures detonation speed continuously in time, without the need to numerically differentiate data, and is a new tool for measuring time-dependent as well as steady detonation speed to high accuracy. It consists of a custom-design optical fiber probe embedded in high explosive. The explosive is detonated and a refractive index discontinuity is produced in the probe at the location of the detonation front by the compression of the detonation. Because this … more
Date: September 26, 2006
Creator: Hare, D; Goosman, D; Lorenz, K & Lee, E
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Enhanced Trace-Fiber Color Discrimination by Electrospray Ionization Mass Spectrometry: A Quantitative and Qualitative Tool for the Analysis of Dyes Extracted from Sub-millimeter Nylon Fibers

Description: The application of electrospray-ionization mass spectrometry (ESI-MS) to trace-fiber color analysis is explored using acidic dyes commonly employed to color nylon-based fibers, as well as extracts from dyed nylon fibers. Qualitative information about constituent dyes and quantitative information about the relative amounts of those dyes present on a single fiber become readily available using this technique. Sample requirements for establishing the color-identity of different samples (i.e., comp… more
Date: September 26, 2002
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Perfluoro(Methylcyclohexane) Tracer Tagging Test and Demonstration

Description: On February 14 and 15, 2000, a demonstration of current perfluorocarbon tagging technology and the future potential of these methods was held at Oak Ridge National Laboratory (ORNL). The demonstration consisted of a brief technical discussion followed by a laboratory demonstration. The laboratory demonstrations included the detection of letters, parcels, briefcases and lockers containing perfluorocarbon-tagged papers. Discrimination between tagged and non-tagged items and between three perfluor… more
Date: September 26, 2000
Creator: Sigman, M.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of high-temperature UV-VIS-NIR spectroscopy for the measurement of free energies of complexation at elevated temperatures

Description: We have developed instrumentation capable of measuring optical absorption spectra over a wavelength range of 200--1200 nm and a temperature range of 20--100{degree}C. This fiber-optic based spectrometer generates data which allow the computation of metal-ligand equilibrium constants. Studies at five temperatures have been completed using praseodymium-diglycolate as a model system. Fundamental thermodynamic values (free energies, enthalpies, entropies) were obtained from the experimentally-deter… more
Date: September 26, 1990
Creator: Robouch, P.; Grant, P.; Torres, R. A.; Baisden, P. A. & Silva, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Organometallic Chemistry of Carbon Dioxide. Final Report for June 1, 1986 - March 31, 2002

Description: Research focused on C{sub 1} transition metal complexes that are relevant to CO{sub 2} activation and fixation. First, we prepared and studied new metallocarboxylic acids, a class of compounds proposed as intermediates in the Water Gas Shift reaction and CO{sub 2} reductions, and the corresponding metallocarboxylate anions. Next, we prepared and structurally characterized a large number of CO{sub 2}-bridged bimetallic compounds (models for metal surface-bound CO{sub 2}) and established structur… more
Date: September 26, 2002
Creator: Gibson, D. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic Phase And Chemical Equilibrium At 0-110 C For The H+-K+-Na+-Cl--H2O System Up To 16 Molal And The HNO3-H2O System Up To 20 Molal Using An Association-Based Pitzer Model Compatible With ASPEN Plus

Description: A status is presented of the parameterization during FY2003 of an association-based Pitzer model to simulate chemical and phase equilibria of acid-chloride-nitrate-mercury aqueous electrolyte systems at 0-100 C within the industry-standard process simulator, ASPEN Plus. Compatibility with ASPEN Plus requires that the Pitzer model used be limited to the third virial coefficient and have the values of b and a1 as originally proposed by Pitzer. Two aqueous models for 0-110 C at atmospheric pressur… more
Date: September 26, 2003
Creator: Nichols, T. T. & Taylor, D. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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