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  Partner: UNT Libraries Government Documents Department
 Decade: 2000-2009
SELECTIVE CATALYTIC REDUCTION OF DIESEL ENGINE NOX EMISSIONS USING ETHANOL AS A REDUCTANT

SELECTIVE CATALYTIC REDUCTION OF DIESEL ENGINE NOX EMISSIONS USING ETHANOL AS A REDUCTANT

Date: August 24, 2003
Creator: (1)Kass, M; Thomas, J; Lewis, S; Storey, J; Domingo, N & Graves, R (2) Panov, A
Description: NOx emissions from a heavy-duty diesel engine were reduced by more than 90% and 80% utilizing a full-scale ethanol-SCR system for space velocities of 21000/h and 57000/h respectively. These results were achieved for catalyst temperatures between 360 and 400 C and for C1:NOx ratios of 4-6. The SCR process appears to rapidly convert ethanol to acetaldehyde, which subsequently slipped past the catalyst at appreciable levels at a space velocity of 57000/h. Ammonia and N2O were produced during conversion; the concentrations of each were higher for the low space velocity condition. However, the concentration of N2O did not exceed 10 ppm. In contrast to other catalyst technologies, NOx reduction appeared to be enhanced by initial catalyst aging, with the presumed mechanism being sulfate accumulation within the catalyst. A concept for utilizing ethanol (distilled from an E-diesel fuel) as the SCR reductant was demonstrated.
Contributing Partner: UNT Libraries Government Documents Department
RELATIONSHIP BETWEEN COMPOSITION AND TOXICITY OF ENGINE EMISSION SAMPLES

RELATIONSHIP BETWEEN COMPOSITION AND TOXICITY OF ENGINE EMISSION SAMPLES

Date: August 24, 2003
Creator: (1)Mauderly, J; Seagrave, J; McDonald & J (2)Eide,I (3)Zielinska, B (4)Lawson, D
Description: Differences in the lung toxicity and bacterial mutagenicity of seven samples from gasoline and diesel vehicle emissions were reported previously [1]. Filter and vapor-phase semivolatile organic samples were collected from normal and high-emitter gasoline and diesel vehicles operated on chassis dynamometers on the Unified Driving Cycle, and the compositions of the samples were measured in detail. The two fractions of each sample were combined in their original mass collection ratios, and the toxicity of the seven samples was compared by measuring inflammation and tissue damage in rat lungs and mutagenicity in bacteria. There was good agreement among the toxicity response variables in ranking the samples and demonstrating a five-fold range of toxicity. The relationship between chemical composition and toxicity was analyzed by a combination of principal component analysis (PCA) and partial least squares regression (PLS, also known as projection to latent surfaces). The PCA /PLS analysis revealed the chemical constituents co-varying most strongly with toxicity and produced models predicting the relative toxicity of the samples with good accuracy. The results demonstrated the utility of the PCA/PLS approach, which is now being applied to additional samples, and it also provided a starting point for confirming the compounds that actually cause the ...
Contributing Partner: UNT Libraries Government Documents Department
Savannah River Ecology Laboratory, Annual Technical Progress Report of Ecological Research, June 30, 2003

Savannah River Ecology Laboratory, Annual Technical Progress Report of Ecological Research, June 30, 2003

Date: June 30, 2003
Creator: (Director), Paul M. Bertsch
Description: No abstract prepared.
Contributing Partner: UNT Libraries Government Documents Department
Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase II

Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase II

Date: September 30, 2005
Creator: (EMTEC), Nick Cannell & (ORNL), Adrian S. Sabau
Description: The investment casting process allows the production of complex-shape parts and close dimensional tolerances. One of the most important phases in the investment casting process is the design of the pattern die. Pattern dies are used to create wax patterns by injecting wax into dies. The first part of the project involved preparation of reports on the state of the art at that time for all the areas under consideration (die-wax, wax-shell, and shell-alloy). The primary R&D focus during Phase I was on the wax material since the least was known about it. The main R&D accomplishments during this phase were determination of procedures for obtaining the thermal conductivity and viscoelastic properties of an unfilled wax and validating those procedures. Phase II focused on die-wax and shell-alloy systems. A wax material model was developed based on results obtained during the previous R&D phase, and a die-wax model was successfully incorporated into and used in commercial computer programs. Current computer simulation programs have complementary features. A viscoelastic module was available in ABAQUS but unavailable in ProCAST, while the mold-filling module was available in ProCAST but unavailable in ABAQUS. Thus, the numerical simulation results were only in good qualitative agreement with experimental ...
Contributing Partner: UNT Libraries Government Documents Department
Performance assessment analyses unique to Department of Energy spent nuclear fuel

Performance assessment analyses unique to Department of Energy spent nuclear fuel

Date: June 4, 2000
Creator: (INEEL), H. H. Loo & (DE&S), J. O. Duguid
Description: This paper describes the iterative process of grouping and performance assessment that has led to the current grouping of the U.S. Department of Energy (DOE) spent nuclear fuel (SNF). The unique sensitivity analyses that form the basis for incorporating DOE fuel into the total system performance assessment (TSPA) base case model are described. In addition, the chemistry that results from dissolution of DOE fuel and high level waste (HLW) glass in a failed co-disposal package, and the effects of disposal of selected DOE SNF in high integrity cans are presented.
Contributing Partner: UNT Libraries Government Documents Department
Gamma-Ray Spectrometric Characterization of Overpacked CC104/107 RH-TRU Wastes: Surrogate Tests

Gamma-Ray Spectrometric Characterization of Overpacked CC104/107 RH-TRU Wastes: Surrogate Tests

Date: May 1, 2000
Creator: (INEEL), J. K. Hartwell; (ANL), R. T. Klann & (INEEL), M. E. McIlwain
Description: Development of the gamma-ray spectrometric technique termed GSAK (Gamma-Ray Spectrometry with Acceptable Knowledge) for the characterization of CC104/107 remote-handled transuranic (RH-TRU) wastes continued this year. Proof-of-principle measurements have been completed on the surrogate RH-TRU waste drums configured earlier this year. The GSAK technique uses conventional gamma-ray spectrometry to quantify the detectable fission product content of overpacked RH-TRU drums. These results are then coupled with the inventory report to characterize the waste drum content. The inventory report is based on process knowledge of the waste drum loading and calculations of the isotopic distribution in the spent fuel examined to generate the drummed wastes. Three RH-TRU surrogate drums were configured with encapsulated EBR-II driver fuel rod segments arranged in the surrogate drum assemblies. Segment-specific inventory calculations initially specified the radionuclide content of the fuel segments and thus the surrogate drums. Radiochemical assays performed on representative fuel element segments identified a problem in the accuracy of some of the fission and activation product inventory values and provided a basis for adjustment of the specified surrogate drum inventories. The three waste drum surrogates, contained within their 8.9 cm (3.5 inch) thick steel overpacks, were analyzed by gamma-ray spectrometry at the TREAT facility at Argonne ...
Contributing Partner: UNT Libraries Government Documents Department
SUPPORTED LIQUID CATALYSTS FOR REMOVAL OF HIGH TEMPERATURE FUEL CELL CONTAMINANTS

SUPPORTED LIQUID CATALYSTS FOR REMOVAL OF HIGH TEMPERATURE FUEL CELL CONTAMINANTS

Date: January 1, 2000
Creator: (PI), Alan W. Weimer; Czerpak, Peter & Hilbert, Patrick
Description: A novel catalytic synthesis gas oxidation process using molten carbonate salts supported on compatible fluidized iron oxide particles (supported-liquid-phase-catalyst (SLPC) fluidized bed process) was investigated. This process combines the advantages of large scale fluidized bed processing with molten salt bath oxidation. Molten salt catalysts can be supported within porous fluidized particles in order to improve mass transfer rates between the liquid catalysts and the reactant gases. Synthesis gas can be oxidized at reduced temperatures resulting in low NO{sub x} formation while trace sulfides and halides are captured in-situ. Hence, catalytic oxidation of synthesis gas can be carried out simultaneously with hot gas cleanup. Such SLPC fluidized bed processes are affected by inter-particle liquid capillary forces that may lead to agglomeration and de-fluidization of the bed. An understanding of the origin and strength of these forces is needed so that they can be overcome in practice. Process design is based on thermodynamic free energy minimization calculations that indicate the suitability of eutectic Na{sub 2}CO{sub 3}/K{sub 2}CO{sub 3} mixtures for capturing trace impurities in-situ (< 1 ppm SO{sub x} released) while minimizing the formation of NO{sub x}(< 10 ppm). Iron oxide has been identified as a preferred support material since it is ...
Contributing Partner: UNT Libraries Government Documents Department
Inverse Process Analysis for the Acquisition of Thermophysical Data

Inverse Process Analysis for the Acquisition of Thermophysical Data

Date: October 31, 2004
Creator: (UTK), Jay Frankel & (UTK), Adrian Sabau
Description: One of the main barriers in the analysis and design of materials processing and industrial applications is the lack of accurate experimental data on the thermophysical properties of materials. To date, the measurement of most of these high-temperature thermophysical properties has often been plagued by temperature lags that are inherent in measurement techniques. These lags can be accounted for with the appropriate mathematical models, reflecting the experimental apparatus and sample region, in order to deduce the desired measurement as a function of true sample temperature. Differential scanning calorimeter (DSC) measurements are routinely used to determine enthalpies of phase change, phase transition temperatures, glass transition temperatures, and heat capacities. In the aluminum, steel, and metal casting industries, predicting the formation of defects such as shrinkage voids, microporosity, and macrosegregation is limited by the data available on fraction solid and density evolution during solidification. Dilatometer measurements are routinely used to determine the density of a sample at various temperatures. An accurate determination of the thermophysical properties of materials is needed to achieve accuracy in the numerical simulations used to improve or design new material processes. In most of the instruments used to measure properties, the temperature is changed according to instrument controllers ...
Contributing Partner: UNT Libraries Government Documents Department
[Catalyst research]. Final Report

[Catalyst research]. Final Report

Date: March 14, 2005
Creator: (deceased), Ian P Rothwell & place), David R McMillin (in his
Description: Research results are the areas of catalyst precursor synthesis, catalyst fluxionality, catalyst stability, polymerization of {alpha}-olefins as well as the chemistry of Group IV and Group V metal centers with aryloxide and arylsulfide ligands.
Contributing Partner: UNT Libraries Government Documents Department
Final Technical Report "Energy Partitioning in Elementary Chemical Reactions"

Final Technical Report "Energy Partitioning in Elementary Chemical Reactions"

Date: October 3, 2005
Creator: (deceased), Richard Bersohn & investigator), James J. Valentini (reporting
Description: This is the final technical report of the subject grant. It describes the scientific results obtained during the reporting period. These results are focused on the reactions of atomic oxygen with terminal alkenes. We have studied the production of vinoxy in these reactions. We have characterized the energy disposal in the reactions and have elaborated the reaction mechanism.
Contributing Partner: UNT Libraries Government Documents Department
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