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Advanced Test Reactor Design Basis Reconstitution Project Issue Resolution Process (open access)

Advanced Test Reactor Design Basis Reconstitution Project Issue Resolution Process

The Advanced Test Reactor (ATR) Design Basis Reconstitution Program (DBRP) is a structured assessment and reconstitution of the design basis for the ATR. The DBRP is designed to establish and document the ties between the Document Safety Analysis (DSA), design basis, and actual system configurations. Where the DBRP assessment team cannot establish a link between these three major elements, a gap is identified. Resolutions to identified gaps represent configuration management and design basis recovery actions. The proposed paper discusses the process being applied to define, evaluate, report, and address gaps that are identified through the ATR DBRP. Design basis verification may be performed or required for a nuclear facility safety basis on various levels. The process is applicable to large-scale design basis reconstitution efforts, such as the ATR DBRP, or may be scaled for application on smaller projects. The concepts are applicable to long-term maintenance of a nuclear facility safety basis and recovery of degraded safety basis components. The ATR DBRP assessment team has observed numerous examples where a clear and accurate link between the DSA, design basis, and actual system configuration was not immediately identifiable in supporting documentation. As a result, a systematic approach to effectively document, prioritize, and …
Date: May 1, 2007
Creator: Winter, Steven D.; Sharp, Gregg L.; Kohn, William E. & McCracken, Richard T.
System: The UNT Digital Library
B(s) physics at CDF and D0 (open access)

B(s) physics at CDF and D0

Run II at the Tevatron has seen an explosion of results related to the B{sub s} meson, ranging from tests of QCD models, to probes of electro-weak symmetry breaking, to direct searches for new physics effects. I will briefly summarize the CDF and D0 B{sub s}-physics programs, describing the suitability of the detectors for doing this kind of physics, and pointing out how our knowledge of important quantities has improved through Run II measurements.
Date: May 1, 2007
Creator: Evans, Harold G.
System: The UNT Digital Library
The bispectrum of galaxies from high-redshift galaxy surveys: Primordial non-Gaussianity and non-linear galaxy bias (open access)

The bispectrum of galaxies from high-redshift galaxy surveys: Primordial non-Gaussianity and non-linear galaxy bias

The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and non-linear bias parameters of intermediate and high-z galaxies, when all measurable triangle configurations down to mildly non-linear scales, where perturbation theory is still valid, are included. The bispectrum is also a powerful probe of primordial non-Gaussianity. The planned galaxy surveys at z {approx}> 2 should yield constraints on non-Gaussian parameters, f{sub NL}{sup loc.} and f{sub NL}{sup eq.}, that are comparable to, or even better than, those from CMB experiments. We study how these constraints improve with volume, redshift range, as well as the number density of galaxies. Finally we show that a halo occupation distribution may be used to improve these constraints further by lifting degeneracies between gravity, bias, and primordial non-Gaussianity.
Date: May 1, 2007
Creator: Sefusatti, Emiliano; /Fermilab; Komatsu, Eiichiro & /Texas U., Astron. Dept.
System: The UNT Digital Library
Carbon Dioxide Separation with Supported Ionic Liquid Membranes (open access)

Carbon Dioxide Separation with Supported Ionic Liquid Membranes

A practical form of CO2 capture at water-gas shift conditions in the IGCC process could serve the dual function of producing a pure CO2 stream for sequestration and forcing the equilibrium-limited shift reaction to completion enriching the stream in H2. The shift temperatures, ranging from the low temperature shift condition of 260°C to the gasification condition of 900°C, limit capture options by diminishing associative interactions which favor removal of CO2 from the gas stream. Certain sorption interactions, such as carbonate formation, remain available but generally involve exceptionally high sorbent regeneration energies that contribute heavily to parasitic power losses. Carbon dioxide selective membranes need only establish an equilibrium between the gas phase and sorption states in order to transport CO2, giving them a potential energetic advantage over other technologies. Supported liquid membranes take advantage of high, liquid phase diffusivities and a solution diffusion mechanism similar to that observed in polymeric membranes to achieve superior permeabilities and selectivites. The primary shortcoming of the supported liquid membranes demonstrated in past research has been the lack of stability caused by volatilization of the transport liquid. Ionic liquids, which possess high CO2 solubility relative to light gases such as H2, are excellent candidates for this …
Date: May 1, 2007
Creator: Luebke, David R.; Ilconich, Jeffery B.; Myers, Christina R. & Pennline, Henry W.
System: The UNT Digital Library
Carbon Nanotube Materials for Substrate Enhanced Control of Catalytic Activity (open access)

Carbon Nanotube Materials for Substrate Enhanced Control of Catalytic Activity

Carbon SWNTs are attractive materials for supporting electrocatalysts. The properties of SWNTs are highly tunable and controlled by the nanotube's circumferential periodicity and their surface chemistry. These unique characteristics suggest that architectures constructed from these types of carbon support materials would exhibit interesting and useful properties. Here, we expect that the structure of the carbon nanotube support will play a major role in stabilizing metal electrocatalysts under extreme operating conditions and suppress both catalyst and support degradation. Furthermore, the chemical modification of the carbon nanotube surfaces can be expected to alter the interface between the catalyst and support, thus, enhancing the activity and utilization of the electrocatalysts. We plan to incorporate discrete reaction sites into the carbon nanotube lattice to create intimate electrical contacts with the catalyst particles to increase the metal catalyst activity and utilization. The work involves materials synthesis, design of electrode architectures on the nanoscale, control of the electronic, ionic, and mass fluxes, and use of advanced optical spectroscopy techniques.
Date: May 1, 2007
Creator: Heben, M.; Dillon, A. C.; Engtrakul, C.; Lee, S. H.; Kelley, R. D. & Kini, A. M.
System: The UNT Digital Library
The Ceramic Waste Form Process at Idaho National Laboratory (open access)

The Ceramic Waste Form Process at Idaho National Laboratory

The treatment of spent nuclear fuel for disposition using an electrometallurgical technique results in two high-level waste forms: a ceramic waste form (CWF) and a metal waste form. Reactive metal fuel constituents, including all the transuranic metals and the majority of the fission products remain in the salt as chlorides and are processed into the CWF. The solidified salt is containerized and transferred to the CWF process where it is ground in an argon atmosphere. Zeolite 4A is ground and then dried in a mechanically-fluidized dryer. The salt and zeolite are mixed in a V-mixer and heated to 500°C to occlude the salt into the structure of the zeolite. The salt-loaded zeolite is cooled, mixed with borosilicate glass frit, and transferred to a crucible, which is placed in a furnace and heated to 925°C. During this process, known as pressureless consolidation, the zeolite is converted to the final sodalite form and the glass thoroughly encapsulates the sodalite, producing a dense, leach-resistant final waste form.
Date: May 1, 2007
Creator: Priebe, Stephen
System: The UNT Digital Library
CFD Analysis for Flow Behavior Characteristics in the Upper Plenum during low flow/low pressure transients for the Gas Cooled Fast Reactor (GCFR) (open access)

CFD Analysis for Flow Behavior Characteristics in the Upper Plenum during low flow/low pressure transients for the Gas Cooled Fast Reactor (GCFR)

Gas coolant at low pressure exhibits poor heat transfer characteristics. This is an area of concern for the passive response targeted by the Generation IV GCFR design. For the first 24 hour period, the decay heat removal for the GCFR design is dependent on an actively powered blower, which also would reduce the temperature in the fuel during transients, before depending on the passive operation. Natural circulation cooling initiates when the blower is stopped for the final phase of the decay heat removal, as under forced convection the core decay heat is adequately cooled by the running blower. The ability of the coolant to flow in the reverse direction or having recirculation, when the blowers are off, necessitates more understanding of the flow behavior characteristics in the upper plenum. The work done here focuses primarily on the period after the blower has been turned off, as the core is adequately cooled when the blowers are running, thus there was no need to carry out the analysis for the first 24 hours. In order to understand the plume behavior for the GCFR upper plenum several cases were run, with air, helium and helium-air mixture. For each case, the FLUENT was used …
Date: May 1, 2007
Creator: Sabharwall, Piyush; Marshall, Theron; Weaver, Kevan & Gougar, Hans
System: The UNT Digital Library
Chemical properties of the transactinide elements studied inliquid phase with SISAK (open access)

Chemical properties of the transactinide elements studied inliquid phase with SISAK

This article starts with a review of the current SISAKliquid-liquid extraction system, as used after the physical preseparatorBGS at LBNL for chemical studies of transactinide elements. Emphasis willbe on new additions and developments. Then the possibilities offered bythe new TASCA separator at GSI and the use of actinide targets at bothGSI and LBNL are discussed with respect to future SISAK transactinideexperiments. Finally, current and future liquid-liquid extraction systemsfor studying elements Rf up to Hs are discussed.
Date: May 1, 2007
Creator: Omtvedt, J. P.; Alstad, J.; Bjornstad, T.; Dullmann, Ch.E.; Gregorich, K.E.; Hoffman, D.C. et al.
System: The UNT Digital Library
E-Cloud Build-up in Grooved Chambers (open access)

E-Cloud Build-up in Grooved Chambers

We simulate electron cloud build-up in a grooved vacuumchamber including the effect of space charge from the electrons. Weidentify conditions for e-cloud suppression and make contact withprevious estimates of an effective secondary electron yield for groovedsurfaces.
Date: May 1, 2007
Creator: Venturini, Marco
System: The UNT Digital Library
Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor (open access)

Combustion Control and Diagnostics Sensor Testing in a Thermal Barrier Coated Combustor

The combustion control and diagnostics sensor (CCADS) continues to be developed as an in-situ combustion sensor, with immediate application to natural gas fired turbines. In-situ combustion monitoring is also expected to benefit advanced power plants of the future, fueled by coal-derived syngas, liquified natural gas (LNG), hydrogen, or hydrogen blend fuels. The in-situ monitoring that CCADS provides can enable the optimal operation of advanced, fuel-flexible turbines for minimal pollutant emissions and maximum efficiency over the full operating range of an advanced turbine. Previous work has demonstrated CCADS as a useful sensor for in-situ monitoring of natural gas combustion, including detection of important combustion events such as flashback and lean blowoff, in experimental combustors without thermal barrier coatings (TBC). Since typical TBC materials are electrical insulators at room temperature, and CCADS operation requires conduction of electrical current to the walls of the combustor, a TBC on the combustion liner was identified as a potential barrier to CCADS operation in commercial application. This paper reports on CCADS experiments in a turbulent lean premixed combustor with a yttria-stabilized zirconia (YSZ) thermal barrier coating on the combustor wall. The tests were conducted at 0.1 MPa (1 atm), with a 15V excitation voltage on the …
Date: May 1, 2007
Creator: Chorpening, B.T.; Dukes, M.G.; Robey, E.H. & Thornton, J.D.
System: The UNT Digital Library
Consideration of In-Growth of Radionuclides for Facility Hazard Categorization (open access)

Consideration of In-Growth of Radionuclides for Facility Hazard Categorization

This paper addresses issues associated with the effects of daughter product in-growth on the hazard categorization of facilities in accordance with DOE-STD-1027-92, “Hazard Categorization and Accident Analysis Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports.” There is a list of issues that occur when performing facility hazard categorizations at DOE facilities. The first issue is when radionuclides are concentrated outside of their natural decay schemes, and the resulting daughter products exceed the hazard category three threshold quantity values (HC3 TQVs) while their parents do not. The second issue is if a parent nuclide is evaluated for the inhalation pathway, and the daughter product is evaluated using a different pathway and methodology. The third issue is when the parent and daughter are evaluated using the same pathway for exposure, but the daughter is significantly more radiotoxic than the parent. Lastly, when the TQVs were derived for hazard categorization, the methodology used involved a 24 hour exposure period during which, for the sake of simplicity, no consideration was given to decay and the subsequent in-growth of daughter products. Facility hazard categorization is a snapshot in time and does not provide an accurate inventory for long term operations and/or storage.
Date: May 1, 2007
Creator: Miller, Mr. Robert E.
System: The UNT Digital Library
CRISPR Recognition Tool (CRT): a tool for automatic detection of clustered regularly interspaced palindromic repeats (open access)

CRISPR Recognition Tool (CRT): a tool for automatic detection of clustered regularly interspaced palindromic repeats

Clustered Regularly Interspaced Palindromic Repeats (CRISPRs) are a novel type of direct repeat found in a wide range of bacteria and archaea. CRISPRs are beginning to attract attention because of their proposed mechanism; that is, defending their hosts against invading extrachromosomal elements such as viruses. Existing repeat detection tools do a poor job of identifying CRISPRs due to the presence of unique spacer sequences separating the repeats. In this study, a new tool, CRT, is introduced that rapidly and accurately identifies CRISPRs in large DNA strings, such as genomes and metagenomes. CRT was compared to CRISPR detection tools, Patscan and Pilercr. In terms of correctness, CRT was shown to be very reliable, demonstrating significant improvements over Patscan for measures precision, recall and quality. When compared to Pilercr, CRT showed improved performance for recall and quality. In terms of speed, CRT also demonstrated superior performance, especially for genomes containing large numbers of repeats. In this paper a new tool was introduced for the automatic detection of CRISPR elements. This tool, CRT, was shown to be a significant improvement over the current techniques for CRISPR identification. CRT's approach to detecting repetitive sequences is straightforward. It uses a simple sequential scan of a …
Date: May 1, 2007
Creator: Bland, Charles; Ramsey, Teresa L.; Sabree, Fareedah; Lowe, Micheal; Brown, Kyndall; Kyrpides, Nikos C. et al.
System: The UNT Digital Library
The D0 level 3 DAQ system: operation and upgrades (open access)

The D0 level 3 DAQ system: operation and upgrades

The D{O} Level 3 data acquisition system for Run II of the Tevatron has been reliably operating since May 2002. Designed to handle average event sizes of 250 kilobytes at a rate of 1 kHz, the system has been upgraded to be able to process more events, doubling its typical output rate from 50 Hz to 100 Hz, while coping with higher event sizes at the beginning of high luminosity collider stores. The system routes and transfers event fragments from 63 VME crates to any of approximately 320 processing nodes. The addition of more farm nodes, the performance of the components, and the running experience are described here.
Date: May 1, 2007
Creator: Garcia-Bellido, Aran; Bose, Tulika; Brooijmans, Gustaaf; Chapin, Doug; Cutts, David; Fuess, Stuart et al.
System: The UNT Digital Library
Dalitz plot analysis of the D+ ---> K- pi+ pi+ decay in the FOCUS experiment (open access)

Dalitz plot analysis of the D+ ---> K- pi+ pi+ decay in the FOCUS experiment

Using data collected by the high energy photoproduction experiment FOCUS at Fermilab we performed a Dalitz plot analysis of the Cabibbo favored decay D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}. This study uses 53653 Dalitz-plot events with a signal fraction of {approx} 97%, and represents the highest statistics, most complete Dalitz plot analysis for this channel. Results are presented and discussed using two different formalisms. The first is a simple sum of Breit-Wigner functions with freely fitted masses and widths. It is the model traditionally adopted and serves as comparison with the already published analyses. The second uses a K-matrix approach for the dominant S-wave, in which the parameters are fixed by first fitting K{pi} scattering data and continued to threshold by Chiral Perturbation Theory. We show that the Dalitz plot distribution for this decay is consistent with the assumption of two body dominance of the final state interactions and the description of these interactions is in agreement with other data on the K{pi} final state.
Date: May 1, 2007
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
System: The UNT Digital Library
Data acquisition, storage and control architecture for the SuperNova Acceleration Probe (open access)

Data acquisition, storage and control architecture for the SuperNova Acceleration Probe

The SuperNova Acceleration Probe (SNAP) instrument is being designed to collect image and spectroscopic data for the study of dark energy in the universe. In this paper, we describe a distributed architecture for the data acquisition system which interfaces to visible light and infrared imaging detectors. The architecture includes the use of NAND flash memory for the storage of exposures in a file system. Also described is an FPGA-based lossless data compression algorithm with a configurable pre-scaler based on a novel square root data compression method to improve compression performance. The required interactions of the distributed elements with an instrument control unit will be described as well.
Date: May 1, 2007
Creator: Prosser, Alan; /Fermilab; Cardoso, Guilherme; Chramowicz, John; Marriner, John; Rivera, Ryan et al.
System: The UNT Digital Library
Determination of Coal Permeability Using Pressure Transient Methods (open access)

Determination of Coal Permeability Using Pressure Transient Methods

Coalbed methane is a significant natural resource in the Appalachian region. It is believed that coalbed methane production can be enhanced by injection of carbon dioxide into coalbeds. However, the influence of carbon dioxide injection on coal permeability is not yet well understood. Competitive sorption of carbon dioxide and methane gases onto coal is a known process. Laboratory experiments and limited field experience indicate that coal will swell during sorption of a gas and shrink during desorption of a gas. The swelling and shrinkage may change the permeability of the coal. In this study, the permeability of coal was determined by using carbon dioxide as the flowing fluid. Coal samples with different dimensions were prepared for laboratory permeability tests. Carbon dioxide was injected into the coal and the permeability was determined by using pressure transient methods. The confining pressure was variedto cover a wide range of depths. The permeability was also determined as a function of exposure time of carbon dioxide while the confining stress was kept constant. CT scans were taken before and after the introduction of carbon dioxide. Results show that the porosity and permeability of the coal matrix was very low. The paper presents experimental data and …
Date: May 1, 2007
Creator: McLendon, T.R.; Siriwardane, H. (West Virginia University, Morgantown, WV); Haljasmaa, I.V.; Bromhal, G.S.; Soong, Y. & Irdi, G.A.
System: The UNT Digital Library
Distributed Energy Resources for Carbon Emissions Mitigation (open access)

Distributed Energy Resources for Carbon Emissions Mitigation

The era of publicly mandated GHG emissions restrictions inthe United States has begun with recent legislation in California andseven northeastern states. Commercial and industrial buildings canimprove the carbon-efficiency of end-use energy consumption by installingtechnologies such as on-site cogeneration of electricity and useful heatin combined heat and power systems, thermally-activated cooling, solarelectric and thermal equipment, and energy storage -- collectively termeddistributed energy resources (DER). This research examines a collectionof buildings in California, the Northeast, and the southern United Statesto demonstrate the effects of regional characteristics such as the carbonintensity of central electricity grid, the climate-driven demand forspace heating and cooling, and the availability of solar insolation. Theresults illustrate that the magnitude of a realistic carbon tax ($100/tC)is too small to incent significant carbon-reducing effects oneconomically optimal DER adoption. In large part, this is because costreduction and carbon reduction objectives are roughly aligned, even inthe absence of a carbon tax.
Date: May 1, 2007
Creator: Firestone, Ryan & Marnay, Chris
System: The UNT Digital Library
Distributed Generation Dispatch Optimization under VariousElectricity Tariffs (open access)

Distributed Generation Dispatch Optimization under VariousElectricity Tariffs

The on-site generation of electricity can offer buildingowners and occupiers financial benefits as well as social benefits suchas reduced grid congestion, improved energy efficiency, and reducedgreenhouse gas emissions. Combined heat and power (CHP), or cogeneration,systems make use of the waste heat from the generator for site heatingneeds. Real-time optimal dispatch of CHP systems is difficult todetermine because of complicated electricity tariffs and uncertainty inCHP equipment availability, energy prices, and system loads. Typically,CHP systems use simple heuristic control strategies. This paper describesa method of determining optimal control in real-time and applies it to alight industrial site in San Diego, California, to examine: 1) the addedbenefit of optimal over heuristic controls, 2) the price elasticity ofthe system, and 3) the site-attributable greenhouse gas emissions, allunder three different tariff structures. Results suggest that heuristiccontrols are adequate under the current tariff structure and relativelyhigh electricity prices, capturing 97 percent of the value of thedistributed generation system. Even more value could be captured bysimply not running the CHP system during times of unusually high naturalgas prices. Under hypothetical real-time pricing of electricity,heuristic controls would capture only 70 percent of the value ofdistributed generation.
Date: May 1, 2007
Creator: Firestone, Ryan & Marnay, Chris
System: The UNT Digital Library
Diversity of Decline-Rate-Corrected Type 1a Supernova Rise times:One Mode or Two? (open access)

Diversity of Decline-Rate-Corrected Type 1a Supernova Rise times:One Mode or Two?

B-band light-curve rise times for eight unusually well-observed nearby Type Ia supernova (SNe) are fitted by a newly developed template-building algorithm, using light-curve functions that are smooth, flexible, and free of potential bias from externally derived templates and other prior assumptions. From the available literature, photometric BVRI data collected over many months, including the earliest points, are reconciled, combined, and fitted to a unique time of explosion for each SN. On average, after they are corrected for light-curve decline rate, three SNe rise in 18.81 {+-} 0.36 days, while five SNe rise in 16.64 {+-} 0.21 days. If all eight SNe are sampled from a single parent population (a hypothesis not favored by statistical tests), the rms intrinsic scatter of the decline-rate-corrected SN rise time is 0.96{sub -0.25}{sup +0.52} days--a first measurement of this dispersion. The corresponding global mean rise time is 17.44 {+-} 0.39 days, where the uncertainty is dominated by intrinsic variance. This value is {approx}2 days shorter than two published averages that nominally are twice as precise, though also based on small samples. When comparing high-z to low-z SN luminosities for determining cosmological parameters, bias can be introduced by use of a light-curve template with an unrealistic …
Date: May 1, 2007
Creator: Strovink, Mark
System: The UNT Digital Library
Error Estimates Derived from the Data for Least-Squares Spline Fitting (open access)

Error Estimates Derived from the Data for Least-Squares Spline Fitting

None
Date: May 1, 2007
Creator: Blair, Jerome
System: The UNT Digital Library
ESTIMATING FATE AND TRANSPORT OF MULTIPLE CONTAMINANTS IN THE VADOSE ZONE USING A MULTI-LAYERED SOIL COLUMN AND THREE-PHASE EQUILIBRIUM PARTITIONING MODEL (open access)

ESTIMATING FATE AND TRANSPORT OF MULTIPLE CONTAMINANTS IN THE VADOSE ZONE USING A MULTI-LAYERED SOIL COLUMN AND THREE-PHASE EQUILIBRIUM PARTITIONING MODEL

Soils at waste sites must be evaluated for the potential of residual soil contamination to leach and migrate to the groundwater beneath the disposal area. If migration to the aquifer occurs, contaminants can travel vast distances and contaminate drinking water wells, thus exposing human receptors to harmful levels of toxins and carcinogens. To prevent groundwater contamination, a contaminant fate and transport analysis is necessary to assess the migration potential of residual soil contaminates. This type of migration analysis is usually performed using a vadose zone model to account for complex geotechnical and chemical variables including: contaminant decay, infiltration rate, soil properties, vadose zone thickness, and chemical behavior. The distinct advantage of using a complex model is that less restrictive, but still protective, soil threshold levels may be determined avoiding the unnecessary and costly remediation of marginally contaminated soils. However, the disadvantage of such modeling is the additional cost for data collection and labor required to apply these models. In order to allay these higher costs and to achieve a less restrictive but still protective clean-up level, a multiple contaminant and multi layered soil column equilibrium partitioning model was developed which is faster, simpler and less expensive to use.
Date: May 1, 2007
Creator: Rucker, G
System: The UNT Digital Library
Exclusive e+e-, di-photon and di-jet production at the Tevatron (open access)

Exclusive e+e-, di-photon and di-jet production at the Tevatron

Results from studies on exclusive production of electron-position pair, di-photon, and dijet production at CDF in proton-antiproton collisions at the Fermilab Tevatron are presented. THe first observation and cross section measurements of exclusive e{sup +}e{sup -} and di-jet production in hadron-hadron collisions are emphasized.
Date: May 1, 2007
Creator: Terashi, Koji
System: The UNT Digital Library
Fast Reactor Spent Fuel Processing: Experience and Criticality Safety (open access)

Fast Reactor Spent Fuel Processing: Experience and Criticality Safety

This paper discusses operational and criticality safety experience associated with the Idaho National Laboratory Fuel Conditioning Facility which uses a pyrometallurgical process to treat spent fast reactor metallic fuel. The process is conducted in an inert atmosphere hot cell. The process starts with chopping metallic fuel elements into a basket. The basket is lowered into molten salt (LiCl-KCl) along with a steel mandrel. Active metal fission products, transuranic metals and sodium metal in the spent fuel undergo chemical oxidation and form chlorides. Voltage is applied between the basket, which serves as an anode, and the mandrel, which serves as a cathode, causing metallic uranium in the spent fuel to undergo electro-chemical oxidation thereby forming uranium chloride. Simultaneously at the cathode, uranium chloride undergoes electro-chemical reduction and deposits uranium metal onto the mandrel. The uranium metal and accompanying entrained salt are placed in a distillation furnace where the uranium melts forming an ingot and the entrained salt boils and subsequently condenses in a separate crucible. The uranium ingots are placed in long term storage. During the ten year operating history, over one hundred criticality safety evaluations were prepared. All criticality safety related limits and controls for the entire process are contained …
Date: May 1, 2007
Creator: Pope, Chad
System: The UNT Digital Library
FermiGrid (open access)

FermiGrid

As one of the founding members of the Open Science Grid Consortium (OSG), Fermilab enables coherent access to its production resources through the Grid infrastructure system called FermiGrid. This system successfully provides for centrally managed grid services, opportunistic resource access, development of OSG Interfaces for Fermilab, and an interface to the Fermilab dCache system. FermiGrid supports virtual organizations (VOs) including high energy physics experiments (USCMS, MINOS, D0, CDF, ILC), astrophysics experiments (SDSS, Auger, DES), biology experiments (GADU, Nanohub) and educational activities.
Date: May 1, 2007
Creator: Yocum, D.R.; Berman, E.; Canal, P.; Chadwick, K.; Hesselroth, T.; Garzoglio, G. et al.
System: The UNT Digital Library