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Prediction of Corrosion of Alloys in Mixed-Solvent Environments

Description: Corrosion is much less predictable in organic or mixed-solvent environments than in aqueous process environments. As a result, US chemical companies face greater uncertainty when selecting process equipment materials to manufacture chemical products using organic or mixed solvents than when the process environments are only aqueous. Chemical companies handle this uncertainty by overdesigning the equipment (wasting money and energy), rather than by accepting increased risks of corrosion failure (personnel hazards and environmental releases). Therefore, it is important to develop simulation tools that would help the chemical process industries to understand and predict corrosion and to develop mitigation measures. To create such tools, we have developed models that predict (1) the chemical composition, speciation, phase equilibria, component activities and transport properties of the bulk (aqueous, nonaqueous or mixed) phase that is in contact with the metal; (2) the phase equilibria and component activities of the alloy phase(s) that may be subject to corrosion and (3) the interfacial phenomena that are responsible for corrosion at the metal/solution or passive film/solution interface. During the course of this project, we have completed the following: (1) Development of thermodynamic modules for calculating the activities of alloy components; (2) Development of software that generates stability diagrams for alloys in aqueous systems; these diagrams make it possible to predict the tendency of metals to corrode; (3) Development and extensive verification of a model for calculating speciation, phase equilibria and thermodynamic properties of mixed-solvent electrolyte systems; (4) Integration of the software for generating stability diagrams with the mixed-solvent electrolyte model, which makes it possible to generate stability diagrams for nonaqueous or mixed-solvent systems; (5) Development of a model for predicting diffusion coefficients in mixed-solvent electrolyte systems; (6) Development of fundamentals of a detailed kinetic model of general corrosion, which includes a detailed treatment of local chemistry changes near …
Date: June 5, 2003
Creator: A. Anderko, P. Wang, R. D. Young, D. P. Riemer, P. McKenzie and M. M. Lencka (OLI Systems Inc.) & Laboratory), S. S. Babu and P. Angelini (Oak Ridge National
Partner: UNT Libraries Government Documents Department
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Electricity: The Road Toward Restructuring

Description: The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
Date: June 27, 2003
Creator: Abel, Amy & Parker, Larry
Partner: UNT Libraries Government Documents Department
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Migration and Entrapment of DNAPLs in Heterogeneous Systems: Impact of Waste and Porous Medium Composition

Description: Previously funded EMSP research efforts were directed towards the quantification of dense non-aqueous phase liquid (DNAPL) migration and entrapment behavior in physically and chemically heterogeneous systems. This research demonstrated that chemical heterogeneities can have a significant influence on DNAPL fate and persistence. Previous work, however, was limited to examination of the behavior of pure DNAPLs in systems with simple and well-defined aqueous and solid surface chemistry. The subsurface chemical environments at many DOE sites, however, are generally more complex than these idealized systems, due to the release of complex mixtures of wastes and more complex physical and chemical heterogeneity. The research undertaken in this project seeks to build upon our previous research experience and expertise to explore the influence of waste and porous media composition on DNAPL migration and entrapment in the saturated zone. DNAPL mixtures and soils typical of those found across the DOE complex will be used in these studies. Many of the experimental procedures and protocols are based upon those developed under previous EMSP funding. This past work also provides the conceptual framework for characterizing and interpreting experimental results, mathematical model development, and inverse modeling protocols. Specific objectives of this research include: (1) Relate measured interfacial properties for representative wastes and soils to parameters such as mineralogy, organic carbon content, pH, ionic strength, and DNAPL acid and base numbers. (2) Assess predictive procedures to estimate interfacial properties for DOE wastes and soils. (3) Deduce mechanisms of interfacial property alteration. (4) Quantify the influence of waste and porous medium composition on hydraulic properties and residual saturation. (5) Develop and assess constitutive hydraulic property and residual saturation models. (6) Explore the migration and entrapment behavior of model DNAPL wastes in spatially an d temporally heterogeneous systems. (7) Development and validation a multiphase flow model to simulate the migration and …
Date: June 1, 2003
Creator: Abriola, Linda M. & Demond, Avery H.
Partner: UNT Libraries Government Documents Department
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Particle-type dependence of azimuthal anisotropy and nuclearmodification of particle production in Au+Au collisions at sNN = 200GeV

Description: We present STAR measurements of the azimuthal anisotropy parameter v{sub 2} and the binary-collision scaled centrality ratio R{sub CP} for kaons and lambdas ({Lambda} + {bar {Lambda}}) at mid-rapidity in Au+Au collisions at {radical}s{sub NN} = 200 GeV. In combination, the v{sub 2} and R{sub CP} particle-type dependencies contradict expectations from partonic energy loss followed by standard fragmentation in vacuum. We establish p{sub T} {approx} 5 GeV/c as the value where the centrality dependent baryon enhancement ends. The K{sub S}{sup 0} and {Lambda} + {bar {Lambda}} v{sub 2} values are consistent with expectations of constituent-quark-number scaling from models of hadron formation by parton coalescence or recombination.
Date: June 18, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
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Rapidity and centrality dependence of proton and anti-proton production from 197Au+197Au collisions at {radical}(s{sub NN}) = 130 GeV

Description: We report on the rapidity and centrality dependence of proton and anti-proton transverse mass distributions from {sup 197}Au + {sup 197}Au collisions at {radical}s{sub NN} = 130 GeV as measured by the STAR experiment at RHIC. Our results are from the rapidity and transverse momentum range of |y| < 0.5 and 0.35 < p{sub t} < 1.00 GeV/c. For both protons and anti-protons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within |y| < 0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton(anti-proton) yields and transverse mass distributions the possibility of pre-hadronic collective expansion may have to be taken into account.
Date: June 20, 2003
Creator: Adams, J.; Adler, C.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Three-pion Hanbury-Brown-Twiss correlations in relativistic heavy-ion collisions from the STAR experiment

Description: Data from the first physics run at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory, Au+Au collisions at {radical}s{sub NN} = 130 GeV, have been analyzed by the STAR Collaboration using three-pion correlations with charged pions to study whether pions are emitted independently at freezeout. We have made a high-statistics measurement of the three-pion correlation function and calculated the normalized three-particle correlator to obtain a quantitative measurement of the degree of chaoticity of the pion source. It is found that the degree of chaoticity seems to increase with increasing particle multiplicity.
Date: June 19, 2003
Creator: Adams, J.; Adler, C.; Ahammed, Z.; Allgower, C.; Amonett, J.; Anderson, B. D. et al.
Partner: UNT Libraries Government Documents Department
open access

A Binary Segmentation Approach for Boxing Ribosome Particles in Cryo EM Micrographs

Description: Three-dimensional reconstruction of ribosome particles from electron micrographs requires selection of many single-particle images. Roughly 100,000 particles are required to achieve approximately 10 angstrom resolution. Manual selection of particles, by visual observation of the micrographs on a computer screen, is recognized as a bottleneck in automated single particle reconstruction. This paper describes an efficient approach for automated boxing of ribosome particles in micrographs. Use of a fast, anisotropic non-linear reaction-diffusion method to pre-process micrographs and rank-leveling to enhance the contrast between particles and the background, followed by binary and morphological segmentation constitute the core of this technique. Modifying the shape of the particles to facilitate segmentation of individual particles within clusters and boxing the isolated particles is successfully attempted. Tests on a limited number of micrographs have shown that over 80 percent success is achieved in automatic particle picking.
Date: June 24, 2003
Creator: Adiga, Umesh P. S.; Malladi, Ravi; Baxter, William & Glaeser, Robert M.
Partner: UNT Libraries Government Documents Department
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Energy efficiency indicators for high electric-load buildings

Description: Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.
Date: June 1, 2003
Creator: Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki & Varone, Frederic
Partner: UNT Libraries Government Documents Department
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A new security model for collaborative environments

Description: Prevalent authentication and authorization models for distributed systems provide for the protection of computer systems and resources from unauthorized use. The rules and policies that drive the access decisions in such systems are typically configured up front and require trust establishment before the systems can be used. This approach does not work well for computer software that moderates human-to-human interaction. This work proposes a new model for trust establishment and management in computer systems supporting collaborative work. The model supports the dynamic addition of new users to a collaboration with very little initial trust placed into their identity and supports the incremental building of trust relationships through endorsements from established collaborators. It also recognizes the strength of a users authentication when making trust decisions. By mimicking the way humans build trust naturally the model can support a wide variety of usage scenarios. Its particular strength lies in the support for ad-hoc and dynamic collaborations and the ubiquitous access to a Computer Supported Collaboration Workspace (CSCW) system from locations with varying levels of trust and security.
Date: June 6, 2003
Creator: Agarwal, Deborah; Lorch, Markus; Thompson, Mary & Perry, Marcia
Partner: UNT Libraries Government Documents Department
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Waste Form and Indrift Colloids-Associated Radionuclide Concentrations: Abstraction and Summary

Description: This Model Report describes the analysis and abstractions of the colloids process model for the waste form and engineered barrier system components of the total system performance assessment calculations to be performed with the Total System Performance Assessment-License Application model. Included in this report is a description of (1) the types and concentrations of colloids that could be generated in the waste package from degradation of waste forms and the corrosion of the waste package materials, (2) types and concentrations of colloids produced from the steel components of the repository and their potential role in radionuclide transport, and (3) types and concentrations of colloids present in natural waters in the vicinity of Yucca Mountain. Additionally, attachment/detachment characteristics and mechanisms of colloids anticipated in the repository are addressed and discussed. The abstraction of the process model is intended to capture the most important characteristics of radionuclide-colloid behavior for use in predicting the potential impact of colloid-facilitated radionuclide transport on repository performance.
Date: June 24, 2003
Creator: Aguilar, R.
Partner: UNT Libraries Government Documents Department
open access

Level Densities and Radiative Strength Functions in 170,171Yb

Description: Level densities and radiative strength functions in {sup 171}Yb and{sup 170}Yb nuclei have been measured with the {sup 171}Yb({sup 3}He, {sup 3}He{prime}{gamma}){sup 171}Yb and {sup 171}Yb({sup 3}He,{alpha}{gamma}){sup 170}Yb reactions. A simultaneous determination of the nuclear level density and the radiative strength function was made. The present data adds to and is consistent with previous results for several other rare earth nuclei. The method will be briefly reviewed and the result from the analysis will be presented. The radiative strength function for {sup 171}Yb is compared to previously published work.
Date: June 9, 2003
Creator: Agvaanluvsan, U; Schiller, A; Becker, J A; Berstein, L A; Guttormsen, M; Mitchell, G E et al.
Partner: UNT Libraries Government Documents Department
open access

Merlot Design

Description: We describe Merlot, a system for delivery of digital imagery over high speed networks. We describe various use cases, the client/server interaction, and the image and network codecs. We also describe some possible applications using Merlot and future work.
Date: June 10, 2003
Creator: Ahern, S D
Partner: UNT Libraries Government Documents Department
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Science Based Stockpile Stewardship and RIA

Description: One aspect of Science Based Stockpile Stewardship (SBSS) is to improve the quality of neutron cross section data for certain isotopes. The isotopes of interest are used to monitor neutron and charged particle fluxes in environments of brief, intense neutron fluxes. The accuracy of flux determination is dependent on the accuracy of cross section data for the stable isotopes loaded into the system and the unstable isotopes produced when the neutrons are incident on the monitor. For isotopes with a half-life greater than one day it is possible, given the production rates of RIA, to make radioactive targets for neutron irradiation. This would require the ability to harvest isotopes at RIA, an onsite radiochemistry facility for processing the harvested material into a target, and an onsite neutron source facility. The radiochemistry facility will need to handle activity levels on the order of 100's of Curie's while the neutron source facility will need to provide high intensity ''monoenergetic'' neutrons from 10's keV to 20 MeV. For isotopes with a half-life much less than one day, only indirect methods can be used to get information on the neutron cross sections because of the lack of a target. Both experimental techniques will be discussed with their impact on the infrastructure at RIA, as well as the general case for the interest of SBSS in RIA.
Date: June 9, 2003
Creator: Ahle, L. E.; Bernstein, L . A.; Hausmann, M. & Vieira, D. J.
Partner: UNT Libraries Government Documents Department
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EARLY ENTRANCE COPRODUCTION PLANT

Description: The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstocks. The objectives of Phase I were to determine the feasibility and define the concept for the EECP located at a specific site; develop a Research, Development, and Testing (RD&T) Plan for implementation in Phase II; and prepare a Preliminary Project Financing Plan. The objective of Phase II is to implement the work as outlined in the Phase I RD&T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and/or other carbonaceous feedstocks. The objective of Phase III is to develop an engineering design package and a financing and testing plan for an EECP located at a specific site. The project's intended result is to provide the necessary technical, economic, and environmental information needed by industry to move the EECP forward to detailed design, construction, and operation.
Date: June 9, 2003
Creator: Ahmed, Mushtaq; Anderson, John H.; Benham, Charles; Berry, Earl R.; Brent, Fred; Demirel, Belma et al.
Partner: UNT Libraries Government Documents Department
open access

Contaminant-Organic Complexes: Their Structure and Energetics in Surface Decontamination Processes

Description: The current debate over possible decontamination processes for DOE facilities is centered on disparate decontamination problems, but the key contaminants (Thorium [Th],uranium [U], and plutonium [Pu]) are universally important. Innovative agents used alone or in conjunction with traditional processes can increase the potential to reclaim for future use some these valuable resources or at the least decontaminate the metal surfaces to allow disposal as nonradioactive, nonhazardous material. This debate underscores several important issues: (1) regardless of the decontamination scenario, metal (Fe, U, Pu, Np) oxide film removal from the surface is central to decontamination; and (2) simultaneous oxide dissolution and sequestration of actinide contaminants against re-adsorption to a clean metal surface will influence the efficacy of a process or agent and its cost. Current research is investigating the use of microbial siderophores (chelates) to solubilize actinides (i.e., Th, U, Pu) from the surface of Fe oxide surfaces. Continuing research integrates (1) studies of macroscopic dissolution/desorption of common actinide (IV) [Th, U, Pu, Np] solids and species sorbed to and incorporated into Fe oxides, (2) molecular spectroscopy (FTIR, Raman, XAS), to probe the structure and bonding of contaminants, siderophores and their functional moieties, and how these change with the chemical environment, (3) and molecular mechanics and electronic structure calculations to design model siderophore compounds to test and extend the MM3 model.
Date: June 2003
Creator: Ainsworth, Calvin C.; Hay, Benjamin P.; Traina, Samuel J. & Myneni, Satish C. B.
Partner: UNT Libraries Government Documents Department
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A Review of Methods for the Manufacture of Residential RoofingMaterials

Description: Shingles, tiles, and metal products comprise over 80% (by roof area) of the California roofing market (54-58% fiberglass shingle, 8-10% concrete tile, 8-10% clay tile, 7% metal, 3% wood shake, and 3% slate). In climates with significant demand for cooling energy, increasing roof solar reflectance reduces energy consumption in mechanically cooled buildings, and improves occupant comfort in non-conditioned buildings. This report examines methods for manufacturing fiberglass shingles, concrete tiles, clay tiles, and metal roofing. The report also discusses innovative methods for increasing the solar reflectance of these roofing materials. We have focused on these four roofing products because they are typically colored with pigmented coatings or additives. A better understanding of the current practices for manufacturing colored roofing materials would allow us to develop cool colored materials creatively and more effectively.
Date: June 1, 2003
Creator: Akbari, Hashem; Levinson, Ronnen & Berdahl, Paul
Partner: UNT Libraries Government Documents Department
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Liquid film/polymer interfaces

Description: The objectives were: (1) Through experimental studies, advance the fundamental understanding of the principles that govern adsorption and wetting phenomena at polymer and organic surfaces. (2) Establish a firm scientific basis for improving the design of coatings for metal fin cooling surfaces used to control the wetting of water condensate for optimum energy efficiency. Several important findings were: (1) water adsorbed at hydrophobic surfaces has a liquid-like structure, in contrast to the generally held view of an ordered structure; (2) Correlations of large amounts of contact angle wetting data of grafted alkyl chain compounds showed a distinct link between the contact angle and the conformational ordering of the chains; (3) water adsorption at long chain alkysiloxane films showed a strong pH dependence on the film stability, which can be attributed to interfacial chemical effects on the siloxane network.
Date: June 12, 2003
Creator: Allara, David L.
Partner: UNT Libraries Government Documents Department
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Reactive Multiphase Behavior of C)2 in Saline Aquifers Beneath the Colorado Plateau

Description: The six coal-fired power plants located in the Colorado Plateau and southern Rocky Mountain region of the U.S. produce 100 million tons of CO{sub 2} per year. Thick sequences of collocated sedimentary rocks represent potential sites for sequestration of the CO{sub 2}. Field and laboratory investigations of naturally occurring CO{sub 2}-reservoirs are being conducted to determine the characteristics of potential seal and reservoir units and the extent of the interactions that occur between the host rocks and the CO{sub 2} charged fluids. The results are being incorporated into a series of two-dimensional numerical models that represent the major chemical and physical processes induced by injection. During reporting period covered here (March 30 to June 30, 2003), the main achievements were: Presentation of three papers at the Second Annual Conference on Carbon Sequestration (May 5-8, Alexandria, Virginia); Presentation of a poster at the American Association of Petroleum Geologists meeting; Co-PI organized and chaired a special session on Geologic Carbon Dioxide Sequestration at the American Association of Petroleum Geologists annual convention in Salt Lake City (May 12-15).
Date: June 30, 2003
Creator: Allis, R. G.; Moore, J. & White, S.
Partner: UNT Libraries Government Documents Department
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A Resolution Analysis of Two Geophysical Imaging Methods for Characterizing and Monitoring Hydrologic Conditions in the Vadose Zone

Description: This project has been designed to analyze the resolution of two different geophysical imaging techniques (electrical resistivity tomography and cross-borehole ground penetrating radar) for monitoring subsurface flow and transport processes within the vadose zone. This is to be accomplished through a coupled approach involving large scale unsaturated flow modeling, petrophysical conversion of the resulting 2 and 3 Dimensional water content and solute concentration fields to geophysical property models and generation of synthetic geophysical data, followed by the inversion of the synthetic geophysical data. The resolution, strengths, and limitations of the geophysical techniques will then be ascertained through an analysis involving comparisons between the original hydrologic modeling results and inverted geophysical images. Increasing levels of complexity will be added to the models as the project progresses through the addition of heterogeneity in the original hydrologic property model, and by adding uncertainty to the petrophysical relationship that couples the geophysical model to the hydrologic modeling results.
Date: June 1, 2003
Creator: Alumbaugh, David L.
Partner: UNT Libraries Government Documents Department
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