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Investigation of Mixed Metal Sorbent/Catalysts for the Simultaneous Removal of Sulfur and Nitrogen Oxides

Description: Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}.
Date: August 1, 2001
Creator: Akyurtlu, Ates & Akyurtle, Jale F.
Partner: UNT Libraries Government Documents Department
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ADVANCED DATA PROCESSING FOR VOLUMETRIC COMPUTED TOMOGRAPHY DATA

Description: Computed tomography (CT) has long been used by industry as a non-destructive evaluation technique for discovering flaws in parts before their use. Traditional linear array computed tomography systems acquired data at a rate that could be reconstructed simultaneously with data acquisition. With new area detectors, the data rate of acquisition has increased exponentially, and the reconstruction algorithm does not scale linearly with increased data. FlashCT DPS (Flat Panel Amorphous Silicon High Resolution Computed Tomography, Data Processing System) is a software package developed by M. Sheats, and A. Davis at LANL to meet the data processing demands of new flat panel array computed tomography. FlashCT--DPS combines several features unique to industrial computed tomography systems. It addresses traditional usability problems by providing an intuitive graphical user interface and powerful analysis tools. It includes the three major CT reconstruction algorithms: parallel backprojection, fan beam resorting, and Feldkamp cone beam. It also provides visualization tools for examination of data after processing. Finally, it is able to perform distributed data reconstruction with a near linear speed increase as a function of the number of processors used. Additionally, utility programs have been developed to support project editing and computing cluster management for the FlashCT system. FlashCT--DPS runs on a standard PC platform and operates well on a variety of processor and memory configurations.
Date: August 1, 2001
Creator: BERKELEY, M. SHEATS - UC
Partner: UNT Libraries Government Documents Department
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TEMPERATURE MEASUREMENTS COLLECTED FROM AN INSTRUMENTED VAN IN SALT LAKE CITY, UTAH AS PART OF URBAN 2000

Description: Measurements of temperature and position were collected during the night from an instrumented van on routes through Salt Lake City and the rural outskirts. The measurements were taken as part of the Department of Energy Chemical and Biological National Security Program URBAN 2 Field Experiment conducted in October 2000 (Shinn et al., 2000 and Allwine et al., 2001a). The instrumented van was driven over three primary routes, two including downtown, residential, and ''rural'' areas and a third that went by a line of permanently fixed temperature probes (Allwine et al., 2001b) for cross-checking purposes. Each route took from 45 to 60 minutes to complete. Based on four nights of data, initial analyses indicate that there was a temperature difference of 2-5 C between the urban core and nearby ''rural'' areas. Analyses also suggest that there were significant fine scale temperature differences over distances of tens of meters within the city and in the nearby rural areas. The temperature measurements that were collected are intended to supplement the meteorological measurements taken during the URBAN2000 Field Experiment, to assess the importance of the urban heat island phenomenon in Salt Lake City, and to test the urban canopy parameterizations that have been developed for regional scale meteorological codes as part of the DOE CBNP program.
Date: August 1, 2001
Creator: BROWN, M. J. & PARDYJAK, E. R.
Partner: UNT Libraries Government Documents Department
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Dry Cask Storage Characterization Project - Phase 1: CASTOR V/21 Cask Opening and Examination

Description: This report documents visual examination and testing conducted in 1999 and early 2000 at the Idaho National Engineering and Environmental Laboratory (INEEL) on a Gesellschaft für Nuklear Service (GNS) CASTOR V/21 pressurized water reactor (PWR) spent fuel dry storage cask. The purpose of the examination and testing is to develop a technical basis for renewal of licenses and Certificates of Compliance for dry storage systems for spent nuclear fuel and high-level waste at independent spent fuel storage installation sites. The examination and testing was conducted to assess the condition of the cask internal and external surfaces, cask contents consisting of 21 Westinghouse PWR spent fuel assemblies from Dominion’s (formerly named Virginia Power) Surry Power Station and cask concrete storage pad. The assemblies have been continuously stored in the CASTOR cask since 1985. Cask exterior surface and selected fuel assembly temperatures, and cask surface gamma and neutron dose rates were measured. Cask external/internal surfaces, fuel basket components including accessible weldments, fuel assembly exteriors, and primary lid seals were visually examined. Selected fuel rods were removed from one fuel assembly, visually examined, and then shipped to Argonne National Laboratory for nondestructive, destructive, and mechanical examination. Cask interior crud samples and helium cover gas samples were collected and analyzed. The results of the examination and testing indicate the concrete storage pad, CASTOR V/21 cask, and cask contents exhibited sound structural and seal integrity and that long-term storage has not caused detectable degradation of the spent fuel cladding or the release of gaseous fission products between 1985 and 1999.
Date: August 1, 2001
Creator: Bare, Walter Claude; Ebner, Matthias Anthony & Torgerson, Laurence Dale
Partner: UNT Libraries Government Documents Department
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Partial Re-vegetation of the Dust and Blowing-Sand Source Area: A proposal for use of a 175 K$ SEP Fine

Description: We propose using the 175 K$ SEP money to stabilize approximately 300-340 acres located to the southwest of the 200 West Expansion Area fence. We propose a procedure that relies on drill seeding a mixture of perennial native grasses followed by truck application of a soil fixative such as Soil Master. This effort would compliment FDH/Duratek activities planned for inside the 200 West fence lines. Assuming that both efforts are successful, the result would be between 2,000 and 2,500 meters of stabilized soil surface upwind of the primary receptors at MO-281/272-WA, which would result in a significant reduction in respirable dust at the receptor site.
Date: August 1, 2001
Creator: Becker, James M. & Sackschewsky, Michael R.
Partner: UNT Libraries Government Documents Department
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Preliminary mode distortion measurements on the Jefferson Lab IRFEL

Description: We previously reported analytical calculations of mirror distortion in a high power FEL with a near-concentric cavity. Naive assumptions about the FEL power vs. distortion led us to believe that mirror losses were much lower than expected. Recently we have directly measured the mode size and beam quality as a function of power using a resonator with a center wavelength of 5 microns. The resonator mirrors were calcium fluoride. This material exhibits a large amount of distortion for a given power but, due to the negative slope of refractive index v temperature, adds almost no optical phase distortion on the laser output. The mode in the cavity can thus be directly calculated from the measurements at the resonator output. The presence of angular jitter produced results inconsistent with cold cavity expectations. Removing the effects of the angular jitter produces results in reasonable agreement with analytical models assuming mirror losses comparable to the original expectations.
Date: August 1, 2001
Creator: Benson, Stephen V.; Gubeli, Joe & Shinn, Michelle D.
Partner: UNT Libraries Government Documents Department
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ADVANCED DIRECT LIQUEFACTION CONCEPTS FOR PETC GENERIC UNITS

Description: The results of Laboratory and Bench-Scale experiments and supporting technical and economic assessments conducted under DOE Contract No. DE-AC22-91PC91040 are reported for the period April 1, 2001 to June 30 2001. This work involves the introduction into the basic two-stage liquefaction process several novel concepts, which include dispersed lower-cost catalysts, coal cleaning by oil agglomeration, and distillate hydrotreating and dewaxing. This project has been modified to include an investigation into the production of value added materials from coal using low-severity liquefaction based technologies.
Date: August 1, 2001
Creator: Berkovich, Adam J.
Partner: UNT Libraries Government Documents Department
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Dualities in M-theory and Born-Infeld Theory

Description: We discuss two examples of duality. The first arises in the context of toroidal compactification of the discrete light cone quantization of M-theory. In the presence of nontrivial moduli coming from the M-theory three form, it has been conjectured that the system is described by supersymmetric Yang-Mills gauge theory on a noncommutative torus. We are able to provide evidence for this conjecture, by showing that the dualities of this M-theory compactification, which correspond to T-duality in Type IIA string theory, are also dualities of the noncommutative supersymmetric Yang-Mills description. One can also consider this as evidence for the accuracy of the Matrix Theory description of M-theory in this background. The second type of duality is the self-duality of theories with U(1) gauge fields. After discussing the general theory of duality invariance for theories with complex gauge fields, we are able to find a generalization of the well known U(1) Born-Infeld theory that contains any number of gauge fields and which is invariant under the maximal duality group. We then find a supersymmetric extension of our results, and also show that our results can be extended to find Born-Infeld type actions in any even dimensional spacetime.
Date: August 1, 2001
Creator: Brace, Daniel, M
Partner: UNT Libraries Government Documents Department
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Mechanical Engineering Safety Note: Analysis and Control of Hazards Associated with NIF Capacitor Module Events

Description: The NIF capacitor module was reviewed with respect to pressure venting and shrapnel containment during failures. A modified module concept was proposed that would adequately vent the pressure, yet be effective at containing shrapnel. Two large vents are provided on each side of the module. These have fixed vent areas, and are immediately accessible for pressure venting at the beginning of a pressure transient. A shrapnel shield is located on the outside of each vent opening forming a chute. The chute contains a collimator. This increases the number of bounces that shrapnel must take on the way out, and directs the shrapnel to the trap beneath. The trap contains a depth of clear pine, sufficient to completely absorb the energy of even the most energetic fragment considered. Based on a review of the evidence from past capacitor failures at the FANTM facility at Sandia National Laboratory, Albuquerque, and additional theoretical estimates, the peak pressure generated in the module during explosive events was estimated to be less than 40 psig. This internal pressure in the FANTM module appears to be tolerable, as only minor damage to the module and to internal components was observed after events. The new module concept proposed here provides increased venting area, fully available at the initiation of an event. It is expected that even less damage would be observed if an event occurred in a module with this design. The module joints and connections were formally reviewed with respect to their tolerance to a brief internal pressure as high as 40 psig. With minor modifications that have been incorporated into the design, the module was shown to maintain its integrity during such events. Some of the calculations performed estimated the quantity of dielectric oil that could be involved in a capacitor failure. It was determined that …
Date: August 1, 2001
Creator: Brereton, S
Partner: UNT Libraries Government Documents Department
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Foraging behavior of three passerines in mature bottomland hardwood forests during summer.

Description: Attention has focused on forest management practices and the interactions between birds and their habitat, as a result of apparent declines in populations of many forest birds. Although avian diversity and abundance have been studied in various forest habitats, avian foraging behavior is less well known. Although there are published descriptions of avian foraging behaviors in the western United States descriptions from the southeastern United States are less common. This article reports on the foraging behavior of the White-eyed Vireo, Northern Parula, and Hooded Warbler in mature bottomland hardwood forests in South Carolina.
Date: August 1, 2001
Creator: Buffington, J., Matthew; Kilgo, John, C.; Sargent, Robert, A.; Miller, Karl, V. & Chapman, Brian, R.
Partner: UNT Libraries Government Documents Department
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EVALUATION OF LAND USE/LAND COVER DATASETS FOR URBAN WATERSHED MODELING

Description: Land use/land cover (LULC) data are a vital component for nonpoint source pollution modeling. Most watershed hydrology and pollutant loading models use, in some capacity, LULC information to generate runoff and pollutant loading estimates. Simple equation methods predict runoff and pollutant loads using runoff coefficients or pollutant export coefficients that are often correlated to LULC type. Complex models use input variables and parameters to represent watershed characteristics and pollutant buildup and washoff rates as a function of LULC type. Whether using simple or complex models an accurate LULC dataset with an appropriate spatial resolution and level of detail is paramount for reliable predictions. The study presented in this paper compared and evaluated several LULC dataset sources for application in urban environmental modeling. The commonly used USGS LULC datasets have coarser spatial resolution and lower levels of classification than other LULC datasets. In addition, the USGS datasets do not accurately represent the land use in areas that have undergone significant land use change during the past two decades. We performed a watershed modeling analysis of three urban catchments in Los Angeles, California, USA to investigate the relative difference in average annual runoff volumes and total suspended solids (TSS) loads when using the USGS LULC dataset versus using a more detailed and current LULC dataset. When the two LULC datasets were aggregated to the same land use categories, the relative differences in predicted average annual runoff volumes and TSS loads from the three catchments were 8 to 14% and 13 to 40%, respectively. The relative differences did not have a predictable relationship with catchment size.
Date: August 1, 2001
Creator: Burian, S. J.; Brown, M. J. & Mcpherson, T. N.
Partner: UNT Libraries Government Documents Department
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The Design-to-Analysis Process at Sandia National Laboratories Observations and Recommendations

Description: The efficiency of the design-to-analysis process for translating solid-model-based design data to computational analysis model data plays a central role in the application of computational analysis to engineering design and certification. A review of the literature from within Sandia as well as from industry shows that the design-to-analysis process involves a number of complex organizational and technological issues. This study focuses on the design-to-analysis process from a business process standpoint and is intended to generate discussion regarding this important issue. Observations obtained from Sandia staff member and management interviews suggest that the current Sandia design-to-analysis process is not mature and that this cross-organizational issue requires committed high-level ownership. A key recommendation of the study is that additional resources should be provided to the computer aided design organizations to support design-to-analysis. A robust community of practice is also needed to continuously improve the design-to-analysis process and to provide a corporate perspective.
Date: August 1, 2001
Creator: Burns, Shawn P.; Harrison, Randy J. & Dobranich, Dean
Partner: UNT Libraries Government Documents Department
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Demolition Range Noise Abatement Technique Demonstration and Evaluation for the McAlester Army Ammunition Plant

Description: Public concern regarding the effects of noise generated by the detonation of excess and obsolete explosive munitions at U.S. Army demolition ranges is a continuing issue for the Army's demilitarization and disposal groups. Recent concerns of citizens living near the McAlester Army Ammunition Plant (MCAAP) in Oklahoma have lead the U.S. Army Defense Ammunition Center (DAC) to conduct a demonstration and evaluation of noise abatement techniques that could be applied to the MCAAP demolition range. With the support of the DAC, MCAAP, and Sandia National Laboratories (SNL), three types of noise abatement techniques were applied: aqueous foams, overburden (using combinations of sand beds and dirt coverings), and rubber or steel blast mats. Eight test configurations were studied and twenty-four experiments were conducted on the MCAAP demolition range in July of 2000. Instrumentation and data acquisition systems were fielded for the collection of near-field blast pressures, far-field acoustic pressures, plant boundary seismic signals, and demolition range meteorological conditions. The resulting data has been analyzed and reported, and a ranking of each technique's effects has been provided to the DAC.
Date: August 1, 2001
Creator: CALDERONE,JAMES J. & GARBIN,H. DOUGLAS
Partner: UNT Libraries Government Documents Department
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VARIATION OF STRIKE INCENTIVES WITH DAMAGE PREFERENCES

Description: For START III level forces, strike allocations and magnitudes vary little with L, but first strike costs vary directly with L, which means that for K reflecting a preference for the survival of high value targets over their destruction and a preference for high value over military targets, the costs of action are far greater than those of inaction for a wide range of values of damage preference L. Thus, if both sides have much greater preferences for the survival of their high value targets than for military targets or destruction, they do not see a net incentive to strike, and crises are terminated by inaction. Recent decades suggest strong preferences for the survival of high value and that this has contributed to the lack of direct conflict during that period.
Date: August 1, 2001
Creator: Canavan, G.
Partner: UNT Libraries Government Documents Department
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COST OF ADDRESSING TARGETS OF UNEQUAL VALUE

Description: The formalism for evaluating first strike costs and incentives for military targeting generalize to include higher value targets. That introduces two new allocations to the usual allocation between missiles and military targets, but they can be performed analytically. As the number of weapons on each side decreases, the optimal fraction of second strike weapons allocated to military values falls. The shift to high value targets is more pronounced below about 1,000 weapons for nominal parameters. Below 500 weapons the first striker's cost of action drops below its cost of inaction. A strike would induce a second strike of about 250 weapons on high value targets. An increase in the first striker's preference for damage to the other's high value targets increases or a decrease in its preference for preventing damage to its own high value targets decreases first strike costs and stability margins. Including defenses complicates allocations slightly. The main effect is increased attrition of second strikes, particularly at larger defenses, which makes it possible to significantly reduce damage to high value targets. At 1,000 weapons, by 300 to 400 interceptors the first striker's costs are reduced to 30% below that of inaction and the number of weapons delivered on the first striker's high value targets is reduced to about 100.
Date: August 1, 2001
Creator: Canavan, G. H.
Partner: UNT Libraries Government Documents Department
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LIMITS ON DEFENSE IN INTERACTIONS BETWEEN DISPARATE FORCES

Description: A strong side can deploy modest defenses without loss of stability if it has a strong preference for the survival of its own high value targets and the weaker side has some survivable weapons. The size of the allowable defenses could be increased by larger preferences for survival of high value targets, K, which cause U not to strike out of self deterrence. Larger values of v, i.e., fewer high value targets, make is possible for T to deter U with fewer penetrating weapons. More survivable T weapons would which directly raise the transitional number of interceptors.
Date: August 1, 2001
Creator: Canavan, G. H.
Partner: UNT Libraries Government Documents Department
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TRANSITION FROM ADVERSARIAL TO COOPERATIVE STRATEGIC INTERACTION

Description: This note extends the game theoretic analysis of strategic conflicts begun in earlier Seminars on Planetary Emergencies to interactions with and without defenses between two or more adversaries with more realistic target structures. It reviews the essentials of game theory as applied to the analysis of strategic decisions, the application of first and second strike costs as payoffs, and solution optimization, which resolves several inconsistencies seen with earlier metrics. The stability of the current bilateral offensive configuration is shown to be high and insensitive to deep reductions in offensive forces, the deployment of limited defenses, and the exchange of significant offensive forces for defenses. The transition from adversarial to cooperative interaction is represented by the progressive reduction of the parameters representing each side's preference for damaging or deterring the other, which monotonically improves stability. Estimates of strike incentives in bilateral and trilateral configurations are reduced by the inclusion of high value targets in both sides' force allocations, which dominates the details of offensive and defensive forces. The shift to high value targets stabilizes trilateral offensive configurations, a result that differs with that from analyses based on military costs only. When defenses are included, they lead to a balance between a large defended side and small undefended side that resembles the balance between two large sides. Including the large side's preference for defense of high value targets in the analyses reduces its strike incentives and thus the small side's incentive to preempt. However, it also removes the large sides' ability to deter, so the stability of multi-polar configurations continues to be controlled by the least stable dyad, which places constraints on the size of defenses that can be deployed stably that could be more stringent than those from the bilateral balance.
Date: August 1, 2001
Creator: Canavan, G. H.
Partner: UNT Libraries Government Documents Department
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