Reduced Pressure Electron Beam Welding Evaluation Activities on a Ni-Cr-Mo Alloy for Nuclear Waste Packages (open access)

Reduced Pressure Electron Beam Welding Evaluation Activities on a Ni-Cr-Mo Alloy for Nuclear Waste Packages

The current waste package design for the proposed repository at Yucca Mountain Nevada, USA, employs gas tungsten arc welding (GTAW) in fabricating the waste packages. While GTAW is widely used in industry for many applications, it requires multiple weld passes. By comparison, single-pass welding methods inherently use lower heat input than multi-pass welding methods which results in lower levels of weld distortion and also narrower regions of residual stresses at the weld TWI Ltd. has developed a Reduced Pressure Electron Beam (RPEB) welding process which allows EB welding in a reduced pressure environment ({le} 1 mbar). As it is a single-pass welding technique, use of RPEB welding could (1) achieve a comparable or better materials performance and (2) lead to potential cost savings in the waste package manufacturing as compared to GTAW. Results will be presented on the initial evaluation of the RPEB welding on a Ni-Cr-Mo alloy (a candidate alloy for the Yucca Mountain waste packages) in the areas of (a) design and manufacturing simplifications, (b) material performance and (c) weld reliability.
Date: September 11, 2003
Creator: Wong, F.; Punshon, C.; Dorsch, T.; Fielding, P.; Richard, D.; Yang, N. et al.
Object Type: Article
System: The UNT Digital Library
Large Diffractive Optics for GEo-Based Earth Surveillance (open access)

Large Diffractive Optics for GEo-Based Earth Surveillance

The natural vantage point for performing Earth-centric operations from space is geosynchronous orbit (GEO); a platform there moves at the same rate as the Earth's surface, so appears to continually ''hover'' over a fixed site on the Earth. Unlike spacecraft in other orbits, which rapidly fly-over targets, a GEO-based platform remains in-position all the time. In order to insure continual access to sites using low earth orbit (LEO) platforms, one needs a large enough constellation ({approx} 50) of spacecraft so that one is always overhead; in contrast, a single GEO platform provides continuous coverage over sites throughout Euro-Asia. This permanent coverage comes, unfortunately, with a stiff price-tag; geosynchronous orbit is 36,000 km high, so space platforms there must operate at ranges roughly 100 times greater than ones located in LEO. For optical-based applications, this extreme range is difficult to deal with; for surveillance the price is a 100-fold loss of resolution, for laser weapons it is a 10,000-fold loss in flux-on-target. These huge performance penalties are almost always unacceptable, preventing us from successfully using GEO-based platforms. In practice, we are forced to either settle for brief, infrequent access to targets, or, if we demand continuous coverage, to invest in large, …
Date: September 11, 2003
Creator: Hyde, R A
Object Type: Report
System: The UNT Digital Library
Neutrinoless Double Beta Decay in Light of SNO Salt Data (open access)

Neutrinoless Double Beta Decay in Light of SNO Salt Data

In the SNO data from its salt run, probably the most significant result is the consistency with the previous results without assuming the 8B energy spectrum. In addition, they have excluded the maximal mixing at a very high confidence level. This has an important implication on the double beta decay experiments. For the inverted or degenerate mass spectrum, we find bar<m_nu>_ee bar> 0.013 eV at 95percent CL, and the next generation experiments can discriminate Majorana and Dirac neutrinos if the invertedor degenerate mass spectrum will be confirmed by the improvements in cosmology, tritium data beta decay, or long-baseline oscillation experiments.
Date: September 11, 2003
Creator: Murayama, Hitoshi & Pena-Garay, Carlos
Object Type: Article
System: The UNT Digital Library
An Ab Initio Approach Towards Engineering Fischer-Tropsch Surface Chemistry (open access)

An Ab Initio Approach Towards Engineering Fischer-Tropsch Surface Chemistry

As the US seeks to develop an energy strategy that reduces the reliance on foreign oil, there is a renewed interest in the research and development of the Fischer Tropsch synthesis for converting syngas into long chain hydrocarbon products. This report investigates some of the basic elementary steps for Fischer-Tropsch synthesis over ideal Pt, Ru and carbon-covered Pt and Ru metal surfaces by using ab initio density functional theoretical calculations. We examine in detail the adsorption sites as well as the binding energies for C, CH, CH{sub 2}, CH3 and CH4 on Pt(111), Ru(0001), 2x2-C-Pt(111) and 2x2-C-Ru(0001). The results indicate that the binding energies increase with decreasing the hydrogen in the fragment molecule, i.e. CH{sub 4} < CH{sub 3} < CH{sub 2} < CH < C. More specifically the work analyzes the elementary steps involved in the activation of methane. This is simply the reverse set of steps necessary for the hydrogenation of C to CH{sub 4}. The results indicate that these hydrocarbon intermediates bind more strongly to Ru than Pt. The introduction of co-adsorbed carbon atoms onto both Ru(0001) as well as Pt(111) significantly increased the overall energies as well as the activation barriers for C-H bond activation. The …
Date: September 11, 2003
Creator: Neurock, Matthew & Chopra, Siddharth
Object Type: Report
System: The UNT Digital Library
A NEW LOG EVALUATION METHOD TO APPRAISE MESAVERDE RE-COMPLETION OPPORTUNITIES (open access)

A NEW LOG EVALUATION METHOD TO APPRAISE MESAVERDE RE-COMPLETION OPPORTUNITIES

Artificial intelligence tools, fuzzy logic and neural networks were used to evaluate the potential of the behind pipe Mesaverde formation in BMG's Mancos formation wells. A fractal geostatistical mapping algorithm was also used to predict Mesaverde production. Additionally, a conventional geological study was conducted. To date one Mesaverde completion has been performed. The Janet No.3 Mesaverde completion was non-economic. Both the AI method and the geostatistical methods predicted the failure of the Janet No.3. The Gavilan No.1 in the Mesaverde was completed during the course of the study and was an extremely good well. This well was not included in the statistical dataset. The AI method predicted very good production while the fractal map predicted a poor producer.
Date: September 11, 2003
Creator: Greer, Albert
Object Type: Report
System: The UNT Digital Library
Improved limit on the electron capture decay Branch of {sup 176}Lu (open access)

Improved limit on the electron capture decay Branch of {sup 176}Lu

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Date: September 11, 2003
Creator: Norman, E.B.; Browne, E.; Goldman, I.D. & Renne, P.R.
Object Type: Article
System: The UNT Digital Library
Collaborative editing within the pervasive collaborative computing environment (open access)

Collaborative editing within the pervasive collaborative computing environment

Scientific collaborations are established for a wide variety of tasks for which several communication modes are necessary, including messaging, file-sharing, and collaborative editing. In this position paper, we describe our work on the Pervasive Collaborative Computing Environment (PCCE) which aims to facilitate scientific collaboration within widely distributed environments. The PCCE provides a persistent space in which collaborators can locate each other, exchange messages synchronously and asynchronously and archive conversations. Our current interest is in exploring research and development of shared editing systems with the goal of integrating this technology into the PCCE. We hope to inspire discussion of technology solutions for an integrated approach to synchronous and asynchronous communication and collaborative editing.
Date: September 11, 2003
Creator: Perry, Marcia & Agarwal, Deb
Object Type: Article
System: The UNT Digital Library
Fuel-Cycle energy and emission impacts of ethanol-diesel blends in urban buses and farming tractors. (open access)

Fuel-Cycle energy and emission impacts of ethanol-diesel blends in urban buses and farming tractors.

About 2.1 billion gallons of fuel ethanol was used in the United States in 2002, mainly in the form of gasoline blends containing up to 10% ethanol (E10). Ethanol use has the potential to increase in the U.S. blended gasoline market because methyl tertiary butyl ether (MTBE), formerly the most popular oxygenate blendstock, may be phased out owing to concerns about MTBE contamination of the water supply. Ethanol would remain the only viable near-term option as an oxygenate in reformulated gasoline production and to meet a potential federal renewable fuels standard (RFS) for transportation fuels. Ethanol may also be blended with additives (co-solvents) into diesel fuels for applications in which oxygenation may improve diesel engine emission performance. Numerous studies have been conducted to evaluate the fuel-cycle energy and greenhouse gas (GHG) emission effects of ethanol-gasoline blends relative to those of gasoline for applications in spark-ignition engine vehicles (see Wang et al. 1997; Wang et al. 1999; Levelton Engineering et al. 1999; Shapouri et al. 2002; Graboski 2002). Those studies did not address the energy and emission effects of ethanol-diesel (E-diesel or ED) blends relative to those of petroleum diesel fuel in diesel engine vehicles. The energy and emission effects of …
Date: September 11, 2003
Creator: Wang, M.; Saricks, C. & Lee, H.
Object Type: Report
System: The UNT Digital Library
Radioactive Waste Evaporation: Current Methodologies Employed for the Development, Design, and Operation of Waste Evaporators at the Savannah River Site and Hanford Waste Treatment Plant (open access)

Radioactive Waste Evaporation: Current Methodologies Employed for the Development, Design, and Operation of Waste Evaporators at the Savannah River Site and Hanford Waste Treatment Plant

Evaporation of High level and Low Activity (HLW and LAW) radioactive wastes for the purposes of radionuclide separation and volume reduction has been conducted at the Savannah River and Hanford Sites for more than forty years. Additionally, the Savannah River Site (SRS) has used evaporators in preparing HLW for immobilization into a borosilicate glass matrix. This paper will discuss the methodologies, results, and achievements of the SRTC evaporator development program that was conducted in support of the SRS and Hanford WTP evaporator processes. The cross pollination and application of waste treatment technologies and methods between the Savannah River and Hanford Sites will be highlighted. The cross pollination of technologies and methods is expected to benefit the Department of Energy's Mission Acceleration efforts by reducing the overall cost and time for the development of the baseline waste treatment processes.
Date: September 11, 2003
Creator: Calloway, T.B.
Object Type: Article
System: The UNT Digital Library
Installing and Running AIM 2.3.1 in a Clustered Server Production Environment (open access)

Installing and Running AIM 2.3.1 in a Clustered Server Production Environment

High availability and redundancy were required for a 24/7 technical baseline at a nuclear production facility. Process engineering, operations, and maintenance all had to connect to the AIM workflow and data management system at the plant. 24-hour availability and 100 percent data integrity were requirements. AIM 2.3.1 satisfied these needs by running in a clustered environment, using shared RAID 5 data storage installed with Oracle Fail Safe on clustered WinNT 4.0 Servers. Order of installation was critical for successful operation. The system has been running in production for 12 months with minimal downtime, and zero loss of data.
Date: September 11, 2003
Creator: Walker, J.H.
Object Type: Article
System: The UNT Digital Library
Tests of the Contamination Analysis Unit, Phase 2 (open access)

Tests of the Contamination Analysis Unit, Phase 2

Lawrence Livermore National Laboratory (LLNL) has developed a mass spectrometer-based system that measures organic surface residues in situ. This system, called the Contamination Analysis Unit (CAU), can detect and quantify a variety of volatile surface residues on a range of different substrates. Residue samples are removed from the substrate using a combination of vacuum and thermal desorption, and are then ionized and quantified by a quadrupole mass spectrometer. The current effort (Phase 2) was carried out in accordance with Thiokol Project Test Plan PTP-0467. A first phase of tests was completed under PTP-0327 and the results reported in TWR-75385. The Phase 2 test plan, PTP-0467, is a follow-on to PTP-0327, and was conducted in order to more fully determine the capabilities of the CAU. This report summarizes experiments in which the CAU was evaluated for application in reusable solid rocket motor production scenarios. The report has been ordered by the tasks requested by ATK Thiokol Propulsion Testplan PTP-0467. Project tasks included the following: (1) Determine the amount of residual propellant and liner components with the CAU after coupons have been cleaned. (2) Determine if the CAU can detect solvent that has soaked into NBR. (3) Test the capabilities of the …
Date: September 11, 2003
Creator: Meltzer, Michael & Daley, Paul
Object Type: Report
System: The UNT Digital Library
Composite Species in the Hydrodynamic Theory of Atomic Mixing in Multicomponent Partially Ionized Gases (open access)

Composite Species in the Hydrodynamic Theory of Atomic Mixing in Multicomponent Partially Ionized Gases

A dynamical description of atomic mixing in multicomponent gases and plasmas was summarized in a previous report (UCRL-ID-145502). That description is based on the use of separate continuity and momentum equations for each species present, including neutral atoms, ions, and free electrons. This level of detail is not always feasible in practical problems, where subsets of species (e.g., neutral atoms of a particular element together with their ionization products) must be grouped or lumped together into composite species or materials to make the problem tractable. A simple procedure for constructing such composite species was outlined in UCRL-ID-145502, but not in sufficient detail to enable implementation. In particular, the treatment of the free electrons presents some subtleties, since they cannot be included in the composite species for dynamical purposes, whereas they are ordinarily lumped together with the atoms and ions that produced them for state equation purposes. Our purpose here is to provide a more complete description of the procedure by which composite species and their evolution equations may be defined and derived. Special attention is given to the problem of how to deal with the free electrons in a manner consistent with the different roles they play in the dynamics …
Date: September 11, 2003
Creator: Ramshaw, J D
Object Type: Report
System: The UNT Digital Library
Characterization of Vadose Zone Sediment: RCRA Borehole 299-E33-338 Located Near the B-BX-BY Waste Management Area (open access)

Characterization of Vadose Zone Sediment: RCRA Borehole 299-E33-338 Located Near the B-BX-BY Waste Management Area

This report summarizes data collected from samples in borehole 299-E33-338 (C3391). Borehole 299-E33-338 was drilled for two purposes. One purpose was for installation of a RCRA ground-water monitoring well and the other was to characterize the in situ soils and background porewater chemistry near WMA B-BX-BY that have been largely uncontaminated by tank farm and crib and trench discharge operations. This borehole was drilled just outside the southeast fence line of the B tank farm. The borehole was drilled between July 23 and August 8, 2001 to a total depth of 80.05 m (275.75 ft) bgs using the cable-tool method (Horton 2002). The water table was contacted at 77.5 m (254.2 ft) bgs and the top of basalt at 82.6 m (271 ft) bgs. Samples to the top of basalt were collected via a drive barrel/splitspoon, before switching to a hard tool to drill 5 feet into the basalt. Nearly continuous core was obtained down to a depth of ~78.6 m (258 ft) bgs. Two hundred and two 2-ft long by 4-in diameter cores were retrieved, which accounts for ~75% the total length of the borehole. Each 2-ft splitspoon contained two 1-ft lexan-lined core segments. The lithology of this borehole …
Date: September 11, 2003
Creator: Lindenmeier, Clark W.; Serne, R. Jeffrey; Bjornstad, Bruce N.; Gee, Glendon W.; Schaef, Herbert T.; Lanigan, David C. et al.
Object Type: Report
System: The UNT Digital Library
Third Quarter Hanford Seismic report for Fiscal year 2003 (open access)

Third Quarter Hanford Seismic report for Fiscal year 2003

Hanford Seismic Monitoring provides an uninterrupted collection of high-quality raw and processed seismic data from the Hanford Seismic Network for the U.S. Department of Energy and its contractors. Hanford Seismic Monitoring also locates and identifies sources of seismic activity and monitors changes in the historical pattern of seismic activity at the Hanford Site. The data are compiled, archived, and published for use by the Hanford Site for waste management, Natural Phenomena Hazards assessments, and engineering design and construction. In addition, the seismic monitoring organization works with the Hanford Site Emergency Services Organization to provide assistance in the event of a significant earthquake on the Hanford Site. The Hanford Seismic Network and the Eastern Washington Regional Network consist of 41 individual sensor sites and 15 radio relay sites maintained by the Hanford Seismic Monitoring staff. For the Hanford Seismic Network, there were 356 triggers during the third quarter of fiscal year 2003. Of these triggers, 141 were earthquakes. Thirty-four earthquakes of the 141 earthquakes were located in the Hanford Seismic Network area. Stratigraphically 15 occurred in the Columbia River basalt, 13 were earthquakes in the pre-basalt sediments, and 6 were earthquakes in the crystalline basement. Geographically, 22 earthquakes occurred in swarm …
Date: September 11, 2003
Creator: Hartshorn, Donald C.; Reidel, Steve P. & Rohay, Alan C.
Object Type: Report
System: The UNT Digital Library
Measuring the Effect of Fuel Chemical Structure on Particulate and Gaseous Emissions using Isotope Tracing (open access)

Measuring the Effect of Fuel Chemical Structure on Particulate and Gaseous Emissions using Isotope Tracing

Using accelerator mass spectrometry (AMS), a technique initially developed for radiocarbon dating and recently applied to internal combustion engines, carbon atoms within specific fuel molecules can be labeled and followed in particulate or gaseous emissions. In addition to examining the effect of fuel chemical structure on emissions, the specific source of carbon for PM can be identified if an isotope label exists in the appropriate fuel source. Existing work has focused on diesel engines, but the samples (soot collected on quartz filters or combustion gases captured in bombs or bags) are readily collected from large industrial combustors as well.
Date: September 11, 2003
Creator: Buchholz, B. A.; Mueller, C. J.; Martin, G. C.; Upatnicks, A.; Dibble, R. W. & Cheng, S.
Object Type: Article
System: The UNT Digital Library
Electron Equivalents REDOX Model for High Level Waste Vitrification (open access)

Electron Equivalents REDOX Model for High Level Waste Vitrification

Control of the REDuction/OXidation (REDOX) equilibrium in high level waste (HLW) glass melters is critical in order to eliminate the formation of metallic species from overly reduced melts while minimizing foaming from overly oxidized melts. To date, formates, nitrates, and manganic species in the melter feeds going to the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF) have been the major parameters influencing melt REDOX. The sludge being processed for inclusion in the next DWPF Sludge Batch contains several organic components that are considered non-typical of DWPF sludge to date, e.g. oxalates and coal. A mechanistic REDOX model was developed to balance any reductants and any oxidants for any HLW melter feed. The model is represented by the number of electrons gained during reduction of an oxidant or lost during oxidation of a reductant. The overall relationship between the REDOX ratio of the final glass and the melter feed is given in terms of the transfer of molar Electron Equivalents.
Date: September 11, 2003
Creator: Jantzen, Carol M.; Koopman, D. C.; Herman, C. C.; Pickett, J. B. & Zamecnik, J. R.
Object Type: Article
System: The UNT Digital Library
Control system for BCP processing facility at FNAL (open access)

Control system for BCP processing facility at FNAL

The surface processing is one of the key elements of superconducting RF cavity fabrication. Safety and reliability are the main requirements for the chemical surface treatment facility being developed at FNAL. Accepting the Buffered Chemical Polishing (BCP) as the baseline process, a ''gravity feed and open etching tank'' approach has been chosen at this stage. This choice resulted in the introduction of a control system with a strong automation since the number of elements to be controlled at different steps of the process is rather big. In order to allow for maximum flexibility, two operational modes were defined within the control system: semi-automatic, which requires an operator's decision to move from one stage to another, and manual. This paper describes the main features of the control system for the BCP facility that is under development at FNAL.
Date: September 11, 2003
Creator: al., Cristian Boffo et
Object Type: Article
System: The UNT Digital Library
Recent results and prospects for high pT physics at D-Zero (open access)

Recent results and prospects for high pT physics at D-Zero

The author presents recent results from the D0 experiment using {approx} 50 pb{sup -1} of data recorded at the center of mass energy of 1.96 TeV at the Fermilab Tevatron. In addition, the author summarizes prospects for high p{sub T} physics at the Tevatron as a function of integrated luminosity.
Date: September 11, 2003
Creator: Gerber, Cecilia Elena
Object Type: Article
System: The UNT Digital Library
Ocean Margins Program: Cape Hatteras Experiment. Final Report (open access)

Ocean Margins Program: Cape Hatteras Experiment. Final Report

The central objectives of the Ocean Margins Program (OMP) were to quantify the oceanographic and meteorological processes affecting the cycling of carbon on the US East Coast Continental Margin.
Date: September 11, 2003
Creator: Pietrafesa, Leonard J.
Object Type: Report
System: The UNT Digital Library
BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO (open access)

BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

The principal research effort for Year 1 of the project is data compilation and the determination of the tectonic and depositional histories of the North Louisiana Salt Basin. In the first three (3) to six (6) months of Year 1, the research focus is on data compilation and the remainder of the year the emphasis is on the tectonic and depositional histories of the basin. No major problems have been encountered to date, and the project is on schedule.
Date: September 11, 2003
Creator: Mancini, Ernest A.
Object Type: Report
System: The UNT Digital Library