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Systems studies of coal-conversion processes using a reference simulator. Final report, March 12, 1976-August 12, 1979

Description: Methodology and general purpose software were developed which do allow computer-aided design and analysis of large scale coal conversion processes. The LINBAL package for larger scale balance calculations was demonstrated to be quick and efficient in solving problems involving over 100 streams, 20 species, and 80 or more flowsheet units. The LSP simulation package embodies constraint handling, recycle calculation, and information management features which are an advance of the state of the art.… more
Date: December 1, 1979
Creator: Reklaitis, G.V.; Sood, M.K.; Soni, Y.; Overturf, B.W.; Wiede, W.; Clark, S. et al.
Partner: UNT Libraries Government Documents Department
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CO + H/sub 2/ reaction over nitrogen-modified iron catalysts. Quarterly technical progress report, October 1, 1983-December 30, 1983. [Denitriding of iron nitrides in both hydrogen and helium]

Description: The synthesis of epsilon-Fe/sub 2.7/N is confirmed by Moessbauer spectroscopy. Carburization of epsilon-iron nitride for 2.5 hours in 3H/sub 2//CO at 523 K starts the formation of a bulk structure similar to that seen during ..gamma..'-iron nitride carburization. Reaction of ..gamma..'-Fe/sub 4/N in 3CO/H/sub 2/ synthesis gas at 523 K shows a better bulk stability than reaction in 3H/sub 2//CO. Kinetic analysis of the product distribution at the higher CO ratio confirms greater activity and sel… more
Date: February 1, 1984
Creator: Delgass, W.N.
Partner: UNT Libraries Government Documents Department
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Nature of atmospheric dust. Progress report to January 15, 1955

Description: Optical microscopic examination of air- and rain-borne dust shows most of the particles to be less than one micron in diameter. Electron microscopic examination of the same dust shows predominantly clusters of particles whose individual diameters are in the range 200 to 1000 A. The residue obtained by filtering rain water through a millipore filter is found to be slightly radioactive in more than half the cases observed.
Date: January 20, 1955
Creator: Heininger, C. & Turkevich, J.
Partner: UNT Libraries Government Documents Department
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Study of the test method for prediction of air conditioning equipment seasonal performance

Description: The test procedure, Method of Testing, Rating and Estimating the Seasonal Performance of Central Air-Conditioners and Heat Pumps Operating in the Cooling Mode, has been analyzed. The analysis of the test procedure incorporated two main functions: (1) to determine the validity of the test procedure; and (2) to determine if there are other alternate methods of obtaining the same results with less testing burden. Data were collected from industry and analyzed for any significant trends. Certain co… more
Date: May 1, 1980
Creator: Thomas, S. B.
Partner: UNT Libraries Government Documents Department
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Study of electrons photoemitted from field emission tips. Progress report, July 1, 1979-March 1, 1980

Description: Photo-induced field emission is a technique which studies electrons that have been photoemitted from a field emission tip. This new experimental method promises to combine the proven utility of both field emission and photoemission for investigating the electronic states near a metal surface. The primary objective of the research being performed is to investigate photo-induced field emitted electrons using a tuneable cw dye laser. To fully exploit this continuously tuneable photon source, a dif… more
Date: February 1, 1980
Creator: Reifenberger, R.
Partner: UNT Libraries Government Documents Department
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In-situ Evaluation of Soil Organic Molecules: Functional Group Chemistry Aggregate Structures, Metal & Surface Complexation Using Soft X-Ray

Description: Organic molecules are common in all Earth surface environments, and their composition and chemistry play an important role in a variety of biogeochemical reactions, such as mineral weathering, nutrient cycling and the solubility and transport of contaminants. However, most of what we know about the chemistry of these molecules comes from spectroscopy and microscopy studies of organic molecules extracted from different natural systems using either inorganic or organic solvents. Although all thes… more
Date: November 30, 2008
Creator: Myneni, Satish, C.
Partner: UNT Libraries Government Documents Department
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Combustion optimization studies for stratified charge and diesel engines. Progress report, October 1, 1978-September 30, 1979

Description: Progress to date is reasonably within the contract schedule in that: (1) the transparent-piston, transparent-head engine is in routine use for visualization experiments; (2) the gaseous fuel injector is routinely used with gaseous propane as a fuel injected into the motored engine; (3) high speed filming and short duration pulsed light single exposure techniques are being used to obtain shadow and schlieren records of gaseous and liquid jets; (4) an LDV system for measuring in-cylinder velociti… more
Date: August 1, 1979
Creator: Steinberger, R.L. & Bracco, F.V.
Partner: UNT Libraries Government Documents Department
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Nuclear Chemistry Project. Progress report, Janary 1, 1979-December 31, 1979

Description: The first on-line operation of the Princeton electron spectrometer was achieved and its capability for fast life time measurements demonstrated. The first operation of the heavy ion source was achieved and beams of 75 meV /sup 12/C/sup +4/ ions and 37 MeV /sup 6/Li/sup +2/ ions demonstrated. The capability of the isotope separator to provide pure mass separated samples of radioisotopes is being utilized for three different applications. The very weak electron capture branch of 19-s krypton 81m … more
Date: December 21, 1979
Partner: UNT Libraries Government Documents Department
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Studies of yrast and continuum states in A = 140 to 160 nuclei. Progress report, January 1, 1981-December 31, 1981

Description: Nuclear structure studies in the A approx. 150 region by ..gamma..-ray spectroscopy following heavy ion induced reactions are summarized. Yrast states of N = 82 nuclei close to the proton drip line have been identified as rather pure (..pi..h/sub 11/2)/sup n/ excitations of seniority 2 and 3. The high-spin level structure of /sup 154/Dy has been determined through the /sup 124/Sn(/sup 34/S,4n..gamma..) reaction. Both the structure and the level lifetimes indicate a transition at I approx. 32 fr… more
Date: January 1, 1982
Creator: Daly, P. J.
Partner: UNT Libraries Government Documents Department
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Theory of energetic trapped particle-induced resistive interchange-ballooning modes

Description: A theory describing the influence of energetic trapped particles on resistive interchange-ballooning modes in tokamaks is presented. It is shown that a population of hot particles trapped in the region of adverse curvature can resonantly interact with and destabilize the resistive interchange mode, which is stable in their absence because of favorable average curvature. The mode is different from the usual resistive interchange mode not only in its destabilization mechanism, but also in that it… more
Date: February 1, 1986
Creator: Biglari, H. & Chen, L.
Partner: UNT Libraries Government Documents Department
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Radiochemical investigations of nuclear properties. Progress report, January 1, 1979-December 31, 1979. [Purdue Univ]

Description: Investigations of the high-spin level spectra of the nuclei /sup 200/Pb, /sup 202/Pb, and /sup 188/Os were completed, and the results are summarized. The results of collaborative studies of high-spin excitations in /sup 147/Tb and /sup 148/Tb are also briefly reported. New studies of A approx. 150 nuclei at very high angular momenta with heavy-ion beams from the Argonne Tandem-Linac were started. 5 figures, 1 table.
Date: January 1, 1980
Creator: Daly, P. J.
Partner: UNT Libraries Government Documents Department
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Radiochemical investigations of nuclear properties. Progress report, October 1, 1977--December 31, 1978. [Summaries of research activities at Purdue Univ]

Description: Results of (..cap alpha..,xn..gamma..) and (Heavy Ion, xn..gamma..) investigations of high spin excitations in spherical and transitional heavy nuclei are summarised. Considerable progress was made in studies of the level structures of /sup 187/,/sup 188/,/sup 189/Pt and of /sup 200/,/sup 201/,/sup 202/Pb. Investigations of the structure of the Z = 64, N = 82 nucleus /sup 146/Gd and of other nuclei consisting of the /sup 146/Gd core plus one, two or three valence nucleons are also briefly descr… more
Date: January 1, 1979
Creator: Daly, P. J.
Partner: UNT Libraries Government Documents Department
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[Transport properties of disordered porous media from the microstructure]

Description: Progress was made in 4 general areas: quantitative characterization of microstructure via n-point distribution functions; determination of bounds on effective properties that depend on these n-point functions (conductivity, NMR, permeability); derivation of cross- property relations; and development of efficient first-passage time algorithms (Brownian-motion simulations) to compute effective diffusion properties.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department
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Integration of Carbon, Nitrogen, and Oxygen Metabolism in Escherichia coli--Final Report

Description: A key challenge for living systems is balancing utilization of multiple elemental nutrients, such as carbon, nitrogen, and oxygen, whose availability is subject to environmental fluctuations. As growth can be limited by the scarcity of any one nutrient, the rate at which each nutrient is assimilated must be sensitive not only to its own availability, but also to that of other nutrients. Remarkably, across diverse nutrient conditions, E. coli grows nearly optimally, balancing effectively the con… more
Date: October 22, 2012
Creator: Rabinowitz, Joshua D; Wingreen, Ned s; Rabitz, Herschel A & Xu, Yifan
Partner: UNT Libraries Government Documents Department
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Scalable Methods for Electronic Excitations and Optical Responses of Nanostructures: Mathematics to Algorithms to Observables

Description: Kohn-Sham density functional theory (DFT) is a powerful, well-established tool for the study of condensed phase electronic structure. However, there are still a number of situations where its applicability is limited. The basic theme of our research is the development of first principles electronic structure approaches for condensed matter that goes beyond what can currently be done with standard implementations ofKohn-Sham DFT. Our efforts to this end have focused on two classes or' methods. T… more
Date: February 2, 2013
Creator: Carter, Emily A
Partner: UNT Libraries Government Documents Department
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Comprehensive Mechanisms for Combustion Chemistry: An Experimental and Numerical Study with Emphasis on Applied Sensitivity Analysis

Description: This project was an integrated experimental/numerical effort to study pyrolysis and oxidation reactions and mechanisms for small-molecule hydrocarbon structures under conditions representative of combustion environments. The experimental aspects of the work were conducted in large-diameter flow reactors, at 0.3 to 18 atm pressure, 500 to 1100 K temperature, and 10<SUP>-2</SUP> to 2 seconds reaction time. Experiments were also conducted to determine reference laminar flame speeds using a premixe… more
Date: April 10, 2009
Creator: Dryer, Frederick L.
Partner: UNT Libraries Government Documents Department
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Final Technical Report, Grant DE-FG02-87ER13714, "Fundamental Studies of Metastable Liquids"

Description: Grant DE-FG02-87ER13714 supported fundamental work on the physical properties of metastable liquids from 6/1/87 to 4/30/08. Renewal proposals were submitted every three years (1990, 1993, 1996, 1999, 2002, 2005), and included, in every case, a detailed Final Technical Report on the previous three years. Accordingly, the bulk of this report covers the final 2-year period 5/1/06 to 4/30/08 of this grant, which is not covered in any of the previous Final Technical Reports. This is preceded by a br… more
Date: March 9, 2009
Creator: Debenedetti, Pablo G.
Partner: UNT Libraries Government Documents Department
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Molecular Simulation of Phase Equilibria for Complex Fluids

Description: The general area of this project was the development and application of novel molecular simulation methods for prediction of thermodynamic and structural properties of complex polymeric, surfactant and ionic fluids. Over this project period, we have made considerable progress in developing novel algorithms to meet the computational challenges presented by the strong or long-range interactions in these systems and have generated data for well-defined mod-els that can be used to test theories and… more
Date: September 9, 2009
Creator: Panagiotopoulos, Athanassios Z.
Partner: UNT Libraries Government Documents Department
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Final Report US Department of Energy DE-FG02-99ER45797

Description: This grant focused on atomistic studies of the dynamics of grain boundaries in metals performed largely using molecular dynamics simulations. One of the foci of this period was on the appropriate thermodynamics � in particular the grain boundary stiffness. We worked with a group of researchers at Carnegie Mellon University to make a comparison between grain growth simulations using our grain boundary thermodynamics data and experiments. A separate focus of the supported research looked at shear… more
Date: February 22, 2013
Creator: Srolovitz, David J. & Haataja, Mikko
Partner: UNT Libraries Government Documents Department
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Systematic Effects in Type-1a Supernovae Surveys from Host Galaxy Spectra

Description: The physical relation between the properties of Type Ia supernovae and their host galaxies is investigated. Such supernovae are used to constrain the properties of dark energy, making it crucial to understand their physical properties and to check for systematic effects relating to the stellar populations of the progenitor stars from which these supernovae arose. This grant found strong evidence for two distinct populations of supernovae, and correlations between the progenitor stellar populati… more
Date: August 23, 2013
Creator: Strauss, Michael A.
Partner: UNT Libraries Government Documents Department
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Reduction and Reoxidation of Soils During & After Uranium Bioremediation; Implications for Long-Term Uraninite Stability & Bioremediation Scheme Implementation

Description: This research focuses on the conditions and rates under which uranium will be remobilized after it has been precipitated biologically, and what alterations can be implemented to increase its long-term stability in groundwater after the injection of an electron donor has been discontinued. Furthermore, this research addresses short-term iron reoxidation as a mechanism to enhance/extend uranium bioremediation under iron reduction, without its remobilization. The research to date has focused on lo… more
Date: June 1, 2005
Creator: Jaffe, Peter R.
Partner: UNT Libraries Government Documents Department
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