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Experience With the SCALE Criticality Safety Cross Section Libraries

Description: This report provides detailed information on the SCALE criticality safety cross-section libraries. Areas covered include the origins of the libraries, the data on which they are based, how they were generated, past experience and validations, and performance comparisons with measured critical experiments and numerical benchmarks. The performance of the SCALE criticality safety cross-section libraries on various types of fissile systems are examined in detail. Most of the performance areas are demonstrated by examining the performance of the libraries vs critical experiments to show general trends and weaknesses. In areas where directly applicable critical experiments do not exist, performance is examined based on the general knowledge of the strengths and weaknesses of the cross sections. In this case, the experience in the use of the cross sections and comparisons with the results of other libraries on the same systems are relied on for establishing acceptability of application of a particular SCALE library to a particular fissile system. This report should aid in establishing when a SCALE cross-section library would be expected to perform acceptably and where there are known or suspected deficiencies that would cause the calculations to be less reliable. To determine the acceptability of a library for a particular application, the calculational bias of the library should be established by directly applicable critical experiments.
Date: August 21, 2000
Creator: Bowman, S. M.
Partner: UNT Libraries Government Documents Department

Tank Waste Remediation System (TWRS) Technical Baseline Summary Description

Description: This revision notes the supersedure of the subject document by concurrent issuance of HNF-1901 ''Technical Baseline Summary Description for the Tank Farm Contractor'', Revision 2. Safe storage mission technical baseline information was absorbed by the new revision of HNF-1901.
Date: April 21, 2000
Creator: TEDESCHI, A.R.
Partner: UNT Libraries Government Documents Department

Project Execution Plan Project 98L-EWW-460 Plutonium Stabilization and Handling DOE 98-D-453

Description: This Project Execution Plan (PEP) describes the management methods and responsibilities of the project participants. Project W-460 is sufficiently large to warrant a stand alone PEP. This project specific PEP describes the relationships and responsibilities of the project team and identifies the technical, schedule, and cost baselines that have been established for the project. The Department of Energy (DOE), Hanford Works (Hanford), at Richland, Wa. currently does not have a system capable of stabilizing or packaging large quantities of plutonium-bearing solids to meet DOE technical standard DOE-STD-3013-99. This project will allow Hanford to meet this standard by installing stabilization and packaging equipment (SPE). The SPE is capable of stabilizing and packaging the current inventory of greater than 30 percent plutonium-bearing materials currently stored in the Plutonium Finishing Plant's (PFP) vaults into 3013 storage containers. The scope of this project is to procure and install the SPE via a Hanford contract and coordination with the Savannah River Site. In addition, the project will modify PFP vaults and upgrade the PFP Laboratory measurement systems. The Facility infrastructure will be modified to support the new SPE system and the new standardized storage container configuration.
Date: June 21, 2000
Creator: MCGRATH, G.M.
Partner: UNT Libraries Government Documents Department

The Design of a Novel Survey for Small Objects in the Solar System

Description: We evaluated several concepts for a new survey for small objects in the Solar System. We designed a highly novel survey for comets in the outer region of the Solar System, which exploits the occultations of relatively bright stars to infer the presence of otherwise extremely faint objects. The populations and distributions of these objects are not known; the uncertainties span orders of magnitude! These objects are important scientifically as probes of the primordial solar system, and programmatically now that major investments may be made in the possible mitigation of the hazard of asteroid or comet collisions with the Earth.
Date: August 21, 2000
Creator: Alcock, C.; Chen, W.P.; de Pater, I.; Lee, T.; Lissauer, J.; Rice, J. et al.
Partner: UNT Libraries Government Documents Department

Dynamic optimization for commercialization of renewable energy: an example for solar photovoltaics

Description: There are several studies of optimal allocation of research and development resources over the time horizon of a project. The primary result of the basic noncompetitive models in this literature is that the optimal strategy is to choose a research intensity and ending date for the project such that the marginal costs of accelerating the project equals the marginal benefits of introducing the product sooner. This literature provides useful insights for the government planner who must allocate R&D resources for renewable energy development. However, several characteristics distinguish the process from the typical R&D planning problem. Specifically, with PV development, where the goal is to maximize the net present value of activities leading to cost reduction in commercial modules, there are (1) significant lag-times between investment in laboratory research and resulting effects in the marketplace, (2) a learning curve associated with the manufacturing process that also reduces the cost s of PV modules, (3) interim benefits from technical advances, (4) no clear end point to the R&D process, but rather a tapering off of the value of advances in technical efficiency, (5) significant uncertainty in the R&D process, (6) a family of products rather than an individual technology, (7) a co-mingling of government and private resources with implications for efficient management. A dynamic model is developed to characterize the optimal intensity and timing of government and private resource allocation for basic research in improving the technical efficiency of cells and subsidies to the manufacturing process to encourage progress on the learning curve. A series of propositions regarding optimal paths for each are examined. While the research is purely analytical, the results are useful for conceptualizing the R&D planning process. They also provide a basis for a numerical study that can address whether current levels and historic patterns of funding are optimal.
Date: April 21, 2000
Creator: Richards, Kenneth, R.; Ashton, W. Bradley & McVeigh, James
Partner: UNT Libraries Government Documents Department

Bottoms-Up In-Situ Vitrification of Hard-to-Treat Buried Mixed Wastes

Description: This Phase I project was designed to demonstrate feasibility of in situ waste destruction and vitrification technology as a means of remediating hard-to-treat buried radioactive and hazardous wastes and focused on proving viability of the concentric graphite arc melter technique as a robust, safe, and economic tool for use as the IWDV process heat source. Oak Ridge National Laboratory provided technical support to Montec Research including the volatile behavior of elements during silicate melting operations and temperature viscosity modeling of silicate melts. Further research will be needed to develop this technology into a competitive remediation technique.
Date: October 21, 2000
Creator: Spalding, B.P.
Partner: UNT Libraries Government Documents Department

An Evaluation of Activated Bismuth Isotopes in Environmental Samples From the Former Western Pacific Proving Grounds

Description: {sup 207}Bi (t{sub 1/2}=32.2 y) was generated by activation of weapons material during a few ''clean'' nuclear tests at the U.S. Western Pacific Proving Grounds of Enewetak and Bikini Atolls. The radionuclides first appeared in the Enewetak environment during 1958 and in the environment of Bikini during 1956. Crater sediments from Bikini with high levels of {sup 207}Bi were analyzed by gamma spectrometry in an attempt to determine the relative concentrations of {sup 208}Bi (t{sup 1/2} = 3.68 x 10{sup 5} y). The bismuth isotopes were probably generated during the ''clean'', 9.3 Mt Poplar test held on 7/12/58. The atom ratio of {sup 208}Bi to {sup 207}Bi (R value) ranges from {approx}12 to over 200 in sections of core sediments from the largest nuclear crater at Bikini atoll. The presence of bismuth in the device is suggested to account for R values in excess of 10.
Date: March 21, 2000
Creator: Robison, W.L.; Brunk, J.A. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Near-Term Demonstration of Benign, Sustainable, Nuclear Power

Description: Nuclear power reactors have been studied, researched, developed, constructed, demonstrated, deployed, operated, reviewed, discussed, praised and maligned in the United States for over half a century. These activities now transcend our national borders and nuclear power reactors are in commercial use by many nations. Throughout the world, many have been built, some have been shut down, and new ones are coming on line. Almost one-fifth of the world's electricity in 1997 was produced from these reactors. Nuclear power is no longer an unknown new technology. A large increase in world electricity demand is projected for the coming century. In lieu of endless research programs on ''new'' concepts, it is now time to proceed vigorously with widespread deployment of the best nuclear power option for which most parameters are already established. Here, we develop an aggressive approach for initiating the deployment of such a system--with the potential to produce over half of the world's electricity by mid-century, and to continue at that level for several centuries.
Date: September 21, 2000
Creator: Walter, C.E.
Partner: UNT Libraries Government Documents Department

Waste Analysis Plan for 241-Z

Description: The 241-2 waste tanks are used to store, treat, and transfer waste to Tank Farms. The sampling requirements are established to identify the composition of the tank waste. The primary goal is to meet the Tank Farms acceptance criteria. Tank Farms will not accept waste without extensive characterization sample data. Process and lab wastes are sampled for suitability prior to routing to Tk-D8. The samples are helpful in tracking the amount of chemical constituents to determine treatment and are required to maintain Pu inventory and criticality prevention limitations. Likewise, the waste is sampled prior to inter-tank transfers. The revised Waste Analysis Plan for 241-2 (WAP) contains current facility, process and waste descriptions. The WAP lists the Double Shell Tank (DST) system acceptance criteria, sampling parameters and required analyses. The characterization data on historical process wastes was deleted. A section on the Tank Farms waste approval procedural process was added to describe the steps necessary and documentation required to transfer waste to the DST system. Failure to collect proper samples will result in Tank Farms' refusal to accept PFP waste until proper sampling conditions are met. This will use up unnecessary time and resources but not place the plant in a hazardous position.
Date: April 21, 2000
Creator: HIRZEL, D.R.
Partner: UNT Libraries Government Documents Department

Superconductivity and structure in La{sub 2{minus}x}M{sub x}CuO{sub 4}, M=Ba, Sr, and (Nd,Sr)

Description: The identification of charge stripes in La{sub 2{minus}x{minus}y}Nd{sub y}Sr{sub x}CuO{sub 4} (Nd-214) has reenergized research on the original high transition temperature {Tc} superconductor, La{sub 2{minus}x}Ba{sub x}CuO{sub 4} (Ba-214), and related compounds. Early in the study of Ba-214, a low temperature phase transition was associated with changes in electrical properties. An apparent suppression of {Tc} near Ba x=0.125, was initially associated with a first order low temperature phase transformation. However, it was later shown that only very near Ba x=0.125 was {Tc} reduced markedly, and that the relationship between crystal structure and {Tc} is more complicated. This review well describe the low temperature crystal structures and microstructures, as well as the superconducting properties as determined from low field (1-100G) dc magnetometer measurements for Ba-214, Nd-214, and La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (Sr-214). The authors will also describe some work in the related La{sub 2{minus}x}Ca{sub x}CuO{sub 4} (Ca-214). A basic knowledge of the interactions among superconductivity and low temperature phases will allow one to better understand the significance of the underlying charge stripe phases.
Date: January 21, 2000
Creator: Moodenbaugh, A. R.
Partner: UNT Libraries Government Documents Department

Top spin and experimental tests

Description: The authors examine pair mass dependence near threshold as a means to measure the spin of the top quark in hadron collisions, and they discuss the possibility that a top quark signal could be hidden among the top events.
Date: March 21, 2000
Creator: Berger, E. L. & Tait, T. M. P.
Partner: UNT Libraries Government Documents Department

Broadening and shifting of the methanol 119 {mu}m gain line of linear and circular polarization by collision with chiral molecules

Description: Evidence of circular dichroism has been observed in the spectral properties of a gas of left-right symmetric molecules. This dichroism comes about as the result of collisions of the symmetric molecules with left-right asymmetric molecules introduced as a buffer gas. In this sense, the dichroism can be said to have been transferred from the chiral buffer molecules to the symmetric, non-chiral molecules of the background vapor. This transferred dichroism appears as broadening in the gain line of the symmetric molecule which is asymmetric with respect to the right or left handedness of a circularly polarized probe. The broadening of the 119 {mu}m line of the methanol molecule was observed using infrared-far infrared double resonance spectroscopy.
Date: June 21, 2000
Creator: Bakos, J.S.; Djotyan, G.; Soerlei, Zsuzsa; Szigeti, J.; Mansfield, D. K. & Sarkozi, J.
Partner: UNT Libraries Government Documents Department

Assessment of surface contamination with contact mechanics

Description: The authors are particularly interested in the work of adhesion measurements as a means to facilitate the understanding of the adhesive failure mechanisms for systems containing encapsulated and bonded components. Of the several issues under investigation, one is the effect of organic contamination on the adhesive strength for several types of polymer/metal interface combinations. The specific question that the authors are trying to address is at what level of contamination does adhesive strength decrease. The use of contact mechanics, the JKR method, is a good approach for studying this question. Another approach being studied is the use of interracial fracture mechanics. The model contaminant is hexadecane--non-polar, medium molecular weight hydrocarbon fluid. They choose hexadecane because it replicates typical machining fluids, is nonreactive with Al surfaces, and should not dissolve readily into the adhesive systems of interest. The application of a uniform, controllable and reproducible hexadecane layer on Al surfaces has proven to be difficult. A primary concern is whether studies of model systems can be extended to systems of technological interest. The JKR theory is a continuum mechanics model of contact between two solid spheres that was developed by Johnson, Kendall and Roberts. The JKR theory is an extension of Hertzian contact theory and attributes the additional increase in the contact area between a soft elastomeric hemisphere to adhesive forces between the two surfaces. The JKR theory allows a direct estimate of the surface free energy of interface as well as the work of adhesion (Wa) between solids. Early studies performed in this laboratory involved the determination of Wa between silicone (PDMS) and Al surfaces in order to establish the potential adhesive failure mechanisms. However, the JKR studies using commercial based PDMS [poly(dimethylsiloxane)] was fraught with difficulty that were attributed to the additives used in commercial PDMS systems. The authors ...
Date: February 21, 2000
Creator: EMERSON,JOHN A.; MILLER,GREGORY V.; SORENSEN,CHRISTOPHER R. & PEARSON,RAYMOND A.
Partner: UNT Libraries Government Documents Department

Using the whole-building design approach to incorporate daylighting into a retail space: Preprint

Description: This paper focuses on implementation of daylighting into the Bighorn Center, a collection of home improvement retail spaces in Silverthorne, Colorado, which were constructed in three phases. Daylighting was an integral part of the design of the Phase 3 building. Energy consultants optimized the daylighting design through detailed modeling using an hourly building energy simulation tool. Energy consultants also used this tool to address the building owner's concerns related to customer comfort and increased product sales.
Date: June 21, 2000
Creator: Hayter, S.; Torcellini, P.; Eastment, M. & Judkoff, R.
Partner: UNT Libraries Government Documents Department

Quality assurance manual for the environmental survey and site assessment program, Oak Ridge Institute for Science and Education

Description: The purpose of this manual is to provide Program policy and oversight for the maintenance of Quality Assurance (QA) and Quality Control (QC) within the Environmental Survey and Site Assessment Program (ESSAP) of Oak Ridge Institute for Science and Education. This manual describes administrative systems, as well as specific quality control procedures, which apply to all functional groups in ESSAP. The sites surveyed under this program are primarily those where residual contamination from previous operations may pose a potential risk to the environment or to the health and safety of those in the immediate vicinity. Other major activities include environmental assessments, training related to decommissioning survey activities, effluent sampling and monitoring, special laboratory analyses, program appraisals and document reviews, consulting on environment-related topics, and technical assistance for guideline development. The methodology for performance of particular field and laboratory activities is presented in the ESSAP Survey Procedures Manual and the Laboratory Procedures Manual.
Date: March 21, 2000
Partner: UNT Libraries Government Documents Department

Ion exchange distribution coefficients for {sup 137}Cs and {sup 99}Tc removal from Hanford tank supernatants AW-101 (Envelope A) and AN-107 (Envelope C)

Description: The current BNFL Inc. flow sheet for the pretreatment of the Hanford High-Level tank wastes includes the use of Superlig{reg_sign} materials in a dual column system for the removal of {sup 137}Cs and {sup 99}Tc from the aqueous fraction of the waste. The Superlig{reg_sign} materials include the cesium selective Superlig 632and Superlig 644 for removal of {sup 137}Csband Superlig 639 for the removal of {sup 99}Tc present as TcO{sub 4}{sup {minus}}. These materials have been developed and supplied by IBC Technologies, Inc., American Fork, UT. The objectives of this work were to: Evaluate the equilibrium behavior of the Superlig materials for the removal of {sup 137}Cs and {sup 99}Tc (as pertechnetate) from AW-101 (Envelope A) and AN-107 (Envelope C) clarified supernatants; Obtain information of the composition of ion exchange feed streams and the pertechnetate/nonpertechnetate fraction in the samples; and Determine some of the Superlig material physical properties including particle size distribution, dry density and water content. To evaluate the equilibrium behavior, batch contacts at a phase ratio of 100 (5 mL of waste solution: 0.05g of exchanger) were conducted with each of the Superlig materials and each of the waste envelope samples. In order to obtain equilibrium data that bounds the expected feed compositions, some of the envelope subsamples were spiked with either CsNO{sub 3} or {sup 99}Tc as pertechnetate. The fraction of nonpertechnetate in the AN-107 sample was estimated by contacting some of the AN-107 sample with a large excess of Superlig 639 (phase ratio of about 1).
Date: March 21, 2000
Creator: Kurath, DE; Blanchard, DL & Bontha, JR
Partner: UNT Libraries Government Documents Department

Fuel conditioning facility zone-to-zone transfer administrative controls.

Description: The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container types for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion.
Date: June 21, 2000
Creator: Pope, C. L.
Partner: UNT Libraries Government Documents Department

Feature based volume decomposition for automatic hexahedral mesh generation

Description: Much progress has been made through these years to achieve automatic hexahedral mesh generation. While general meshing algorithms that can take on general geometry are not there yet; many well-proven automatic meshing algorithms now work on certain classes of geometry. This paper presents a feature based volume decomposition approach for automatic Hexahedral Mesh generation. In this approach, feature recognition techniques are introduced to determine decomposition features from a CAD model. The features are then decomposed and mapped with appropriate automatic meshing algorithms suitable for the correspondent geometry. Thus a formerly unmeshable CAD model may become meshable. The procedure of feature decomposition is recursive: sub-models are further decomposed until either they are matched with appropriate meshing algorithms or no more decomposition features are detected. The feature recognition methods employed are convexity based and use topology and geometry information, which is generally available in BREP solid models. The operations of volume decomposition are also detailed in the paper. The final section, the capability of the feature decomposer is demonstrated over some complicated manufactured parts.
Date: February 21, 2000
Creator: LU,YONG; GADH,RAJIT & TAUTGES,TIMOTHY J.
Partner: UNT Libraries Government Documents Department

Visible imaging of edge turbulence in NSTX

Description: Edge plasma turbulence in tokamaks and stellarators is believed to cause the radial heat and particle flux across the separatrix and into the scrape-off-layers of these devices. This paper describes initial measurements of 2-D space-time structure of the edge density turbulence made using a visible imaging diagnostic in the National Spherical Torus Experiment (NSTX). The structure of the edge turbulence is most clearly visible using a method of ''gas puff imaging'' to locally illuminate the edge density turbulence.
Date: June 21, 2000
Creator: Zweben, S.; Maqueda, R.; Hill, K.; Johnson, D.; Kaye, S.; Kugel, H. et al.
Partner: UNT Libraries Government Documents Department

High heat-load absorbers for the APS storage ring

Description: The power density of the dipole x-rays in the 7-GeV APS storage ring is 261 watts/mrad at 300 mA of beam current. An array of absorbers is used in the ring to shield its vacuum chambers and diagnostics components in the path of these intense x-rays. This paper describes some of the unique absorber designs that were developed to handle the requirements of high power density and UHV compatibility with no water-to-vacuum joints.
Date: July 21, 2000
Creator: Sharma, S.; Rotela, E. & Barcikowski, A.
Partner: UNT Libraries Government Documents Department

Groundwater quality assessment plan for single-shell tank waste management Area U at the Hanford Site

Description: Waste Management Area U (WMA U) includes the U Tank Farm, is currently regulated under RCRA interim-status regulations, and is scheduled for closure probably post-2030. Groundwater monitoring has been under an evaluation program that compared general contaminant indicator parameters from downgradient wells to background values established from upgradient wells. One of the indicator parameters, specific conductance, exceeded its background value in one downgradient well triggering a change from detection monitoring to a groundwater quality assessment program. The objective of the first phase of this assessment program is to determine whether the increased concentrations of nitrate and chromium in groundwater are from WMA U or from an upgradient source. Based on the results of the first determination, if WMA U is not the source of contamination, then the site will revert to detection monitoring. If WMA U is the source, then a second part of the groundwater quality assessment plan will be prepared to define the rate and extent of migration of contaminants in the groundwater and their concentrations.
Date: March 21, 2000
Creator: Hodges, FN & Chou, CJ
Partner: UNT Libraries Government Documents Department