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Geomechanical Performance of Hydrate-Bearing Sediment in Offshore Environments

Description: The objective of this multi-year, multi-institutional research project was to develop the knowledge base and quantitative predictive capability for the description of geomechanical performance of hydrate-bearing sediments (hereafter referred to as HBS) in oceanic environments. The focus was on the determination of the envelope of hydrate stability under conditions typical of those related to the construction and operation of offshore platforms. We have developed a robust numerical simulator of … more
Date: March 31, 2008
Creator: Holditch, Stephen; Patzek, Tad; Rutqvist, Jonny; Moridis, George & Plumb, Richard
Partner: UNT Libraries Government Documents Department
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IGR NO{sub x}/SO{sub x} control technology. [Quarterly] report, July 1, 1993--September 30, 1993

Description: During the term of this report substantial progress was made in two areas critical to the IGR NOx/SOx control technology. First, an acceptable methodology was developed for the preparation of the selective electrocatalysts required for NOx/SOx destruction. Second, a clear and reproducible destruction of both SOx and NOx was achieved in separate tests using electrocatalysts prepared by the current methodology.
Date: December 31, 1993
Partner: UNT Libraries Government Documents Department
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Spectroscopy, reaction, and photodissociation in highly vibrationally excited molecules. Technical progress report

Description: Highly vibrationally excited molecules often control the course of chemical reactions in the atmosphere, combustion, plasmas, and many other environments. The research described in this Progress Report uses laser excitation and interrogation techniques to study and control the dynamics of highly vibrationally excited molecules. In particular, they show that it is possible to unravel the details and influence the course of photodissociation and bimolecular reaction. The experiments use laser exc… more
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department
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The Dynamics of Adsorption on Clean and Adsorbate-Modified Transition Metal and Metal Oxide Surfaces

Description: Research directed toward understanding the dynamical factors governing the adsorption of molecules typically involved in heterogeneous catalytic processes has been continued. Adsorption is the first step in any catalytic process, and predictions of rates of adsorption are fundamental to calculations of rates of catalytic reactions. Dissociative adsorption can occur either directly upon impact with the surface or as the result of the migration of a temporarily trapped species across the surface.… more
Date: March 31, 2006
Creator: Madix, Robert J.
Partner: UNT Libraries Government Documents Department
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Ground movements associated with gas hydrate production. Progress report, April 1, 1992--June 30, 1992

Description: An obvious consequence of hydrate dissociation is the compression of reservoir matrix causing displacements in the surrounding area. The reservoir compression is a time-dependent process which depends on the production rate. The ground movements cause additional stresses in the overburden which may result in rock mass fracture and failure. Rock failure may cause rubble formation or bulking in the fracture zone. This in turn can cause an increase in permeability for gas flow which may offset the… more
Date: December 31, 1992
Creator: Siriwardane, H. J.
Partner: UNT Libraries Government Documents Department
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Effects of catalytic mineral matter on CO/CO{sub 2} temperature and burning time for char combustion. Quarterly progress report No. 13, October--December 1992

Description: The heat released by formation of CO{sub 2} is a factor of 3.5 higher than for CO so the temperature of a particle will depend strongly on the CO/CO{sub 2} ratio produced. If gas diffusion through the boundary of CO{sub 2} produces a higher temperature and a higher burning rate. If the supply of oxygen to the surface is limited by diffusion through the boundary layer, production of CO{sub 2} consumes half as much carbon as production of CO so carbon consumption rate is reduced even though tempe… more
Date: December 31, 1992
Creator: Longwell, J. P.; Sarofim, A. F.; Lee, Chun-Hyuk & Chen, C.
Partner: UNT Libraries Government Documents Department
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A Mechanistic Investigation of Nitrogen Evolution and Corrosion with Oxy-Combustion

Description: A premixed, staged, down-fired, pulverized coal reactor and a flat flame burner were used to study the evolution of nitrogen in coal contrasting differences in air and oxy-combustion. In the premixed reactor, the oxidizer was staged to produce a fuel rich zone followed by a burnout zone. The initial nominal fuel rich zone stoichiometric ratio (S.R.) of 0.85 selected produced higher NO reductions in the fuel rich region under oxy-combustion conditions. Air was found to be capable of similar NO r… more
Date: December 31, 2008
Creator: Tree, Dale; Mackrory, Andrew & Fletcher, Thomas
Partner: UNT Libraries Government Documents Department
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Feasibility of Large-Scale Ocean CO2 Sequestration

Description: Scientific knowledge of natural clathrate hydrates has grown enormously over the past decade, with spectacular new findings of large exposures of complex hydrates on the sea floor, the development of new tools for examining the solid phase in situ, significant progress in modeling natural hydrate systems, and the discovery of exotic hydrates associated with sea floor venting of liquid CO{sub 2}. Major unresolved questions remain about the role of hydrates in response to climate change today, an… more
Date: August 31, 2008
Creator: Brewer, Peter
Partner: UNT Libraries Government Documents Department
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Advanced Hydrogen Transport Membranes for Vision 21 Fossil Fuel Plants

Description: During this quarter composite layered membrane size was scaled-up and tested for permeation performance. Sintering conditions were optimized for a new cermet containing a high permeability metal and seals were developed to allow permeability testing. Theoretical calculations were performed to determine potential sulfur tolerant hydrogen dissociation catalysts. Finally, work was finalized on mechanical and process & control documentation for a hydrogen separation unit.
Date: October 31, 2005
Creator: Evenson, Carl R.; Wright, Harold A.; Calihman, Adam E.; Balachandran, U.; Kleiner, Richard N.; Stephan, James E. et al.
Partner: UNT Libraries Government Documents Department
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ENVIROMENTALLY BENIGN MITIGATION OF MICROBIOLOGICALLY INFLUENCED CORROSION (MIC)

Description: The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. The technical approach for this quarter includes… more
Date: October 31, 2003
Creator: Paterek, J. Robert; Husmillo, Gemma; Daram, Amrutha & Trbovic, Vesna
Partner: UNT Libraries Government Documents Department
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Development of Laser-Ion Beam Photodissociation Methods

Description: OAK-B135 Our BES funded research is aimed at determining structure(s) of model gas-phase ions and understanding how structure influences unimolecular reactivity. The model gas-phase ions include positional isomers of di- and tri-amino acids synthesized in my laboratory, i.e., RGG, GRG, and GGR, to peptides derived from proteolytic digestion of biologically relevant proteins. We are especially interested in understanding the role of intramolecular interactions in the stabilizing ion structure an… more
Date: March 31, 2004
Creator: Russell, David H.
Partner: UNT Libraries Government Documents Department
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High Pressure Heterogeneous Catalysis in a Low Pressure Ultrahigh Vacuum Environment. Summary of Progress Report, July 1, 1989--December 31, 1992

Description: An apparatus was been developed which couples high resolution electron energy loss spectroscopy with molecular beam and scattering techniques. Exposure of Ni(111) to atomic H results in H embedded within the Ni lattice and a monolayer of H adsorbed on the surface. This surface-bound H was removed by an Xe atom beam. Subsequent exposure to CH{sub 4} results in dissociative adsorption, producing adsorbed CH{sub 3} and adsorbed H. Results documents a new mechanism for a surface reaction, a reactio… more
Date: December 31, 1992
Creator: Ceyer, S. T.
Partner: UNT Libraries Government Documents Department
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Atomic probes of surface structure and dynamics. Technical progress report, September 15, 1991--September 14, 1992

Description: The following were studied: New semiclassical method for scattering calculations, He atom scattering from defective Pt surfaces, He atom scattering from Xe overlayers, thermal dissociation of H{sub 2} on Cu(110), spin flip scattering of atoms from surfaces, and Car-Parrinello simulations of surface processes.
Date: December 31, 1992
Creator: Heller, E. J. & Jonsson, H.
Partner: UNT Libraries Government Documents Department
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Photodissociation and Spectroscopy of Gas Phase Bimetallic Clusters. Final Report, September 15, 1990--September 14, 1993

Description: Focus is the study of gas phase metal clusters to evaluate their potential to model fundamental interactions on metal surfaces. Chemical bonding between component atoms in metal clusters and physisorption on cluster surfaces are studied. Electronic spectra, vibrational frequencies, and bond dissociation energies are measured for both neutral and ionized clusters using laser/mass spectrometry. Interest is on bimetallic cluster systems and how they compare to pure metal clusters. The following we… more
Date: December 31, 1993
Creator: Duncan, M. A.
Partner: UNT Libraries Government Documents Department
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A NOVEL ENERGY EFFICIENT PLASMA CHEMICAL PROCESS FOR THE DESTRUCTION OF VOLATILE TOXIC COMPOUNDS

Description: Destruction of low-concentrations (below several percent) of toxic volatile compounds from contaminated air stream is encountered at the DOE waste sites in the following instances: (i) off-gases resulting from air-stripping of highly-contaminated water and soil (contaminated with DNAPLs, VOCs, etc), (ii) effluent from the incineration of highly-concentrated combustible hazardous wastes. If the contaminated air stream has concentrations of a few parts per million (ppm) then passive methods, such… more
Date: December 31, 2000
Creator: Pinnaduwage, Lal A.
Partner: UNT Libraries Government Documents Department
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Unimolecular reaction dynamics of well characterized ionic reactions. Final report, 1993--1997

Description: The dissociation dynamics of well characterized and energy selected ions have been investigated by photoelectron photoion coincidence (PEPICO) spectrometry. A number of ions have been found which dissociate in competition with isomerization and which thus lead to multi-component decay rates. The dissociation dynamics on such complex potential energy surfaces are common for many free radical reactions, including some of importance to combustion processes. Individual reaction rates for isomerizat… more
Date: December 31, 1997
Creator: Baer, T.
Partner: UNT Libraries Government Documents Department
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Catalytic extraction processing of contaminated scrap metal

Description: The contract was conceived to establish the commercial capability of Catalytic Extraction Processing (CEP) to treat contaminated scrap metal in the DOE inventory. In so doing, Molten Metal Technology, Inc. (MMT), pursued the following objectives: demonstration of the recycling of ferrous and non-ferrous metals--to establish that radioactively contaminated scrap metal can be converted to high-grade, ferrous and non-ferrous alloys which can be reused by DOE or reintroduced into commerce; immobili… more
Date: December 31, 1994
Creator: Griffin, T.P. & Johnston, J.E.
Partner: UNT Libraries Government Documents Department
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Chemical and electrical properties of cavities in silicon and germanium

Description: Cavities were formed in Si and Ge by He ion implantation and annealing, and resultant chemical and electrical properties were investigated. The dissociation energies for Si-H and Ge-H surface monohydride bonds were determined, showing that H chemisorption on Si is energetically stable with respect H{sub 2} gas whereas H chemisorption on Ge is not. Cavity walls in Si were found to trap transition metals strongly, suggesting application to impurity gettering in devices. Measurement and modeling o… more
Date: December 31, 1994
Creator: Myers, S. M.; Follstaedt, D. M.; Petersen, G. A.; Seager, C. H.; Stein, H. J. & Wampler, W. R.
Partner: UNT Libraries Government Documents Department
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Theoretical studies of surface reactions on metals and electronic materials. Progress report, October 1, 1990--January 31, 1993

Description: Studies of a variety of adsorbates on Ni have been completed; adsorption energies were determined for CH, CH{sub 2}, CH{sub 3}, H, NH{sub 3}, H{sub 2}O, and C{sub 6}H{sub 6} on Ni(111). A refined calculation of the reaction of methane with Ni was completed. Other studies included H{sub 2} and SiH{sub 4} adsorption/decomposition on Si surfaces, Si-Si dimer bond length, activity energy barriers for reaction of CH{sub 4}and CH{sub 3}F with Si(111). Studies were begun on deposition of C on Ni(111).… more
Date: January 31, 1993
Creator: Whitten, J. L.
Partner: UNT Libraries Government Documents Department
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Theoretical studies of surface reactions on metals and electronic materials

Description: Studies of a variety of adsorbates on Ni have been completed; adsorption energies were determined for CH, CH[sub 2], CH[sub 3], H, NH[sub 3], H[sub 2]O, and C[sub 6]H[sub 6] on Ni(111). A refined calculation of the reaction of methane with Ni was completed. Other studies included H[sub 2] and SiH[sub 4] adsorption/decomposition on Si surfaces, Si-Si dimer bond length, activity energy barriers for reaction of CH[sub 4]and CH[sub 3]F with Si(111). Studies were begun on deposition of C on Ni(111).… more
Date: January 31, 1993
Creator: Whitten, J. L.
Partner: UNT Libraries Government Documents Department
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