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An Alternative Host Matrix Based on Iron Phosphate Glasses for the Vitrification of Specialized Waste Forms (open access)

An Alternative Host Matrix Based on Iron Phosphate Glasses for the Vitrification of Specialized Waste Forms

As mentioned above, the overall goal of this research project was to collect the scientific information essential to develop iron phosphate glass based nuclear wasteforms. The specific objectives of the project were: (1) Investigate the structure of binary iron phosphate glasses and it's dependence on the composition and melting atmosphere: Understand atomic arrangements and nature of the bonding. Establish structure-property relationships. Determine the compositions and melting conditions which optimize the critical properties of the base glass. (2) Understand the structure of iron phosphate wasteforms and it's dependence on the composition and melting atmosphere: Investigate how the waste elements are bonded and coordinated within the glass structure. Establish structure-property relationships for the waste glasses. Determine the compositions and melting atmosphere for which the critical properties of the waste forms would be optimum. (3) Determine the role(s) played by the valence states of iron ions and it's dependence on the composition and melting atmosphere: Understand the different roles of iron(II) and iron(III) ions in determining the critical properties of the base glass and the waste forms. Investigate how the iron valence and its significance depend on the composition and melting atmosphere. (4) Investigate glass forming and crystallization processes of the iron phosphate …
Date: December 31, 2000
Creator: Day, Delbert D.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 101, No. 250, Ed. 1 Sunday, December 31, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 250, Ed. 1 Sunday, December 31, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analytical and Numerical Solutions of Generalized Fokker-Planck Equations - Final Report (open access)

Analytical and Numerical Solutions of Generalized Fokker-Planck Equations - Final Report

The overall goal of this project was to develop advanced theoretical and numerical techniques to quantitatively describe the spreading of a collimated beam of charged particles in space, in angle, and in energy, as a result of small deflection, small energy transfer Coulomb collisions with the target nuclei and electrons. Such beams arise in several applications of great interest in nuclear engineering, and include electron and ion radiotherapy, ion beam modification of materials, accelerator transmutation of waste, and accelerator production of tritium, to name some important candidates. These applications present unique and difficult modeling challenges, but from the outset are amenable to the language of ''transport theory'', which is very familiar to nuclear engineers and considerably less-so to physicists and material scientists. Thus, our approach has been to adopt a fundamental description based on transport equations, but the forward peakedness associated with charged particle interactions precludes a direct application of solution methods developed for neutral particle transport. Unique problem formulations and solution techniques are necessary to describe the transport and interaction of charged particles. In particular, we have developed the Generalized Fokker-Planck (GFP) approach to describe the angular and radial spreading of a collimated beam and a renormalized transport model …
Date: December 31, 2000
Creator: Prinja, Anil K.
Object Type: Report
System: The UNT Digital Library
Aqueous Electrochemical Mechanisms in Actinide Residue Processing (open access)

Aqueous Electrochemical Mechanisms in Actinide Residue Processing

Plutonium and uranium residues (e.g., incinerator ash, combustibles, and sand/slag/crucibles) resulting from the purification and processing of nuclear materials constitute an enormous volume of ''lean'' processing waste and represent a significant fraction of the U. S. Department of Energy's (DOE) legacy waste from fifty years of nuclear weapons production activities. Much of this material is presently in storage at sites throughout the DOE weapons production complex (most notably Rocky Flats, Savannah River and Hanford) awaiting further processing and/or final disposition. The chemical and physical stability of much of this material has been called into question recently by the Defense Nuclear Facility Safety Board (DNFSB) and resulted in the issuance of a mandate by the DNFSB to undertake a program to stabilize these materials [1]. The ultimate disposition for much of these materials is anticipated to be geologic repositories such as the proposed Waste Isolation Pilot Plant in New Mexico. However, in light of the mandate to stabilize existing residues and the probable concomitant increase in the volume of material to be disposed as a result of stabilization (e.g., from repackaging at lower residue densities), the projected storage volume for these wastes within anticipated geologic repositories will likely be exceeded simply …
Date: December 31, 2000
Creator: Morris, David E.; Burns, Carol J.; Smith, Wayne H. & Blanchard
Object Type: Report
System: The UNT Digital Library
Basin Analysis of the Mississippi Interior Salt Basin and Petroleum System Modeling of the Jurassic Smackover Formation, Eastern Gulf Coastal Plain (open access)

Basin Analysis of the Mississippi Interior Salt Basin and Petroleum System Modeling of the Jurassic Smackover Formation, Eastern Gulf Coastal Plain

Part 3 (Petroleum System Modeling of the Jurassic Smackover Formation) objectives are to provide an analysis of the Smackover petroleum system in Years 4 and 5 of the project and to transfer effectively the research results to producers through workshops and topical reports. Work Accomplished (Year 5): Task 1 - Basin Flow - Basin flow modeling has been completed and the modeling results are being interpreted for report writing (Table 1). Task 2 - Petroleum Source Rocks - Work on the characterization of Smackover petroleum source rocks has been integrated into the basin flow model. Task 3 - Petroleum Reservoirs - Work on the characterization of Smackover petroleum reservoirs continues. The cores to be described have been identified and many of the cores for the eastern part of the basin have been described. Task 4 - Reservoir Diagenesis - Work on reservoir diagenesis has been initiated. Samples from the cores selected for the reservoir characterization are being used for this task. Work Planned (Year 5): Task 1 - Basin Flow - The report on basin flow will be completed. Task 2 - Petroleum Source Rocks - Petroleum source rock data will be reviewed in light of the basin flow model …
Date: December 31, 2000
Creator: Mancini, Ernest
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 35, Ed. 1 Sunday, December 31, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 35, Ed. 1 Sunday, December 31, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: December 31, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Bioavailability Of Organic Solvents In Soils: Input Into Biologically Based Dose-Response Models for Human Risk Assessments (open access)

Bioavailability Of Organic Solvents In Soils: Input Into Biologically Based Dose-Response Models for Human Risk Assessments

The purpose of this study is to determine the bioavailability of organic solvents following dermal exposures to contaminated soil and water. Breath analysis is being used to obtain real-time measurements of volatile organics in expired air following exposure in rats and humans. Rhesus monkeys were used as surrogates for humans in benzene exposures. The exhaled breath data was analyzed using physiologically based pharmacokinetic (PBPK) models to determine the dermal bioavailability of organic solvents under realistic exposure conditions. The end product of this research will be a tested framework for the rapid screening of real and potential exposures while simultaneously developing PBPK models to comprehensively evaluate and compare exposures to organic compounds from either contaminated soil or water.
Date: December 31, 2000
Creator: Wester, Ronald C.
Object Type: Report
System: The UNT Digital Library
BIOFILTRATION OF VOLATILE POLLUTANTS: Fundamental Mechanisms for Improved Design, Long-term Operation, Prediction, and Implementation (open access)

BIOFILTRATION OF VOLATILE POLLUTANTS: Fundamental Mechanisms for Improved Design, Long-term Operation, Prediction, and Implementation

Biofiltration systems can be used for treatment of volatile organic compounds (VOCs); however, the systems are poorly understood and are normally operated as ''black boxes''. Common operational problems associated with biofilters include fouling, deactivation, and overgrowth, all of which make them ineffective for continuous, long-term use. The objective of this investigation was to develop generic methods for long-term stable operation, in particular by using selective limitation of supplemental nutrients while maintaining high activity. As part of this effort, we have provided a deeper fundamental understanding of the important biological and transport mechanisms in biodestruction of sparingly soluble VOCs and have extended this approach and mathematical models to additional systems of high priority EM relevance--direct degradation and cometabolic degradation of priority pollutants such as BTEX and chlorinated organics. Innovative aspects of this project included development of a user-friendly two-dimensional predictive model/program for MS Windows 95/98/2000 to elucidate mass transfer and kinetic limitations in these systems, isolation of a unique microorganism capable of using sparingly soluble organic and chloroorganic VOCs as its sole carbon and energy source, and making long-term growth possible by successfully decoupling growth and degradation metabolisms in operating trickle bed bioreactors.
Date: December 31, 2000
Creator: Davison,Brian H.
Object Type: Report
System: The UNT Digital Library

[Blue and yellow fish looks at the photographer]

Fotografía de un pez azul y amarillo que mira al fotógrafo mientras nada sobre la grava blanca del fondo del acuario.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Characterization of Chemically Modified Enzymes for Bioremediation Reactions (open access)

Characterization of Chemically Modified Enzymes for Bioremediation Reactions

Remediation processes frequently involve species possessing limited solubility in water. For this project, we were interested in novel strategies using molecularly modified enzymes with enhanced activity and stability for remediation of recalcitrant compounds in organic solvents. Performance of naturally occurring enzymes is usually quite limited in such organic environments. The primary objective of the work was to gain a fundamental understanding of the molecular and catalytic properties of enzymes that have been chemically modified so that they are catalytically active and chemically stable in organic solvents. The premise was that stabilized and activated enzymes, which can function under harsh chemical conditions, are optimally suited for bioremediation in nonaqueous media where substrates of interest are more soluble and processed with greater efficiency. This unique strategy was examined with respect to the degradation of chlorophenols and PCBs.
Date: December 31, 2000
Creator: Davison, Brian H.
Object Type: Report
System: The UNT Digital Library

[Children look at a jaguar behind a glass wall]

A live jaguar stands behind a glass wall while small children look on.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Close-up of identification cards]

None
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Close-up of woman's paperwork]

None
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Confined excitons, phonons and their interactions in Ge nanocrystals embedded in SiO2 (open access)

Confined excitons, phonons and their interactions in Ge nanocrystals embedded in SiO2

The authors report the resonant Raman scattering of the optical phonon in Ge nanocrystals with radius ranging from 2 to 5 nm. They have observed the effect of quantum confinement on both the optical phonon and the E{sub 1} exciton. The confinement energy of the E{sub 1} exciton has been explained within the effective mass approximation.
Date: December 31, 2000
Creator: Teo, K. L.; Kwok, S. H. & Yu, P. Y.
Object Type: Article
System: The UNT Digital Library

[Dark form of a shark swims overhead]

The dark form of a shark looms overhead.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The Portal to Texas History
Design and Development of A New Hybrid Spectroelectrochemical Sensor (open access)

Design and Development of A New Hybrid Spectroelectrochemical Sensor

The general aim of this project is to design and implement a new sensor technology that offers the unprecedented levels of specificity needed for analysis of the complex chemical mixtures found at USDOE sites nationwide. The new sensor concept combines the elements of electrochemistry, spectroscopy and selective partitioning into a single device that provides three levels of selectivity. We have had three major goals: Demonstration of the general sensor concept on seven model systems; Development of a prototype sensor for ferrocyanide with associated instrumentation; and Testing prototype sensor for ferrocyanide on waste tank simulant (U-Plant-2 Simulant Solution) provided by PNNL and then on actual tank waste (Tank 241-C-112) at PNNL/Hanford
Date: December 31, 2000
Creator: Heineman, William R.; Seliskar, Carl J. & Ridgway, Thomas
Object Type: Report
System: The UNT Digital Library
DETERMINING SIGNIFICANT ENDPOINTS FOR ECOLOGICAL RISK ANALYS ES (open access)

DETERMINING SIGNIFICANT ENDPOINTS FOR ECOLOGICAL RISK ANALYS ES

Our interest is in obtaining a scientifically defensible endpoint for measuring ecological risks to populations exposed to chronic, low-level radiation, and radiation with concomitant exposure to chemicals. To do so, we believe that we must understand the extent to which molecular damage is detrimental at the individual and population levels of biological organization. Ecological risk analyses based on molecular damage, without an understanding of the impacts to higher levels of biological organization, could cause cleanup strategies on DOE sites to be overly conservative and unnecessarily expensive. Our goal is to determine the relevancy of sublethal cellular damage to the performance of individuals and populations. We think that we can achieve this by using novel biological dosimeters in controlled, manipulative dose/effects experiments, and by coupling changes in metabolic rates and energy allocation patterns to meaningful population response variables (such as age-specific survivorship, reproductive output, age at maturity and longevity).
Date: December 31, 2000
Creator: Hinton, Thomas G.
Object Type: Report
System: The UNT Digital Library
Engineering Development of Coal-Fired High Performance Power Systems (open access)

Engineering Development of Coal-Fired High Performance Power Systems

This report presents work carried out under contract DE-AC22-95PC95144 ''Engineering Development of Coal-Fired High Performance Systems Phase II and III.'' The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) that is capable of: thermal efficiency (HHV) {ge} 47% NOx, SOx, and particulates {le} 10% NSPS (New Source Performance Standard) coal providing {ge} 65% of heat input all solid wastes benign cost of electricity {le}{le} 90% of present plants Phase I, which began in 1992, focused on the analysis of various configurations of indirectly fired cycles and on technical assessments of alternative plant subsystems and components, including performance requirements, developmental status, design options, complexity and reliability, and capital and operating costs. Phase I also included preliminary R&D and the preparation of designs for HIPPS commercial plants approximately 300 MWe in size. Phase II, had as its initial objective the development of a complete design base for the construction and operation of a HIPPS prototype plant to be constructed in Phase III. As part of a descoping initiative, the Phase III program has been eliminated and work related to the commercial plant design has been ended. The rescoped program retained a program of engineering research …
Date: December 31, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Engineering Development of Coal-Fired High-Performance Power Systems Progress Report: October-December 2000 (open access)

Engineering Development of Coal-Fired High-Performance Power Systems Progress Report: October-December 2000

A High Performance Power System (HIPPS) is being developed. This system is a coal-fired, combined cycle plant with indirect heating of gas turbine air. Foster Wheeler Development Corporation and a team consisting of Foster Wheeler Energy Corporation, Bechtel Corporation, University of Tennessee Space Institute and Westinghouse Electric Corporation are developing this system. In Phase 1 of the project, a conceptual design of a commercial plant was developed. Technical and economic analyses indicated that the plant would meet the goals of the project which include a 47 percent efficiency (HHV) and a 10 percent lower cost of electricity than an equivalent size PC plant. The concept uses a pyrolysis process to convert coal into fuel gas and char. The char is fired in a High Temperature Advanced Furnace (HITAF). The HITAF is a pulverized fuel-fired boiler/air heater where steam is generated and gas turbine air is indirectly heated. The fuel gas generated in the pyrolyzer is then used to heat the gas turbine air further before it enters the gas turbine. The project is currently in Phase 2 which includes engineering analysis, laboratory testing and pilot plant testing. Research and development is being done on the HIPPS systems that are not …
Date: December 31, 2000
Creator: Tsuo, York
Object Type: Report
System: The UNT Digital Library
Engineering Development of Slurry Bubble Column Reactor (SBCR) Technology Quarterly Technical Progress Report: Number 23 (open access)

Engineering Development of Slurry Bubble Column Reactor (SBCR) Technology Quarterly Technical Progress Report: Number 23

The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large-diameter reactors. Washington University's work during the reporting period involved the implementation of the automated calibration device, which will provide an advanced method of determining liquid and slurry velocities at high pressures. This new calibration device is intended to replace the original calibration setup, which depended on fishing lines and hooks to position the radioactive particle. The report submitted by Washington University contains a complete description of the new calibration device and its operation. Improvements to the calibration program are also discussed. Iowa State University utilized air-water bubble column …
Date: December 31, 2000
Creator: Toseland, Bernard A.
Object Type: Report
System: The UNT Digital Library
Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma (open access)

Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma

None
Date: December 31, 2000
Creator: Brett, J. Ford & Westermark, Robert V.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, December 31, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Sunday, December 31, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Final technical report [Molecular genetic analysis of biophotolytic hydrogen production in green algae] (open access)

Final technical report [Molecular genetic analysis of biophotolytic hydrogen production in green algae]

The principal objective of this project was to identify genes necessary for biophotolytic hydrogen production in green algae, using Chlamydomonas reinhardtii as an experimental organism. The main strategy was to isolate mutants that are selectively deficient in hydrogen production and to genetically map, physically isolate, and ultimately sequence the affected genes.
Date: December 31, 2000
Creator: Mets, Laurens
Object Type: Report
System: The UNT Digital Library

[Flamingos feeding]

A group of orange flamingos eat from a metal food dish set on rocks in their pond.
Date: December 31, 2000
Creator: Castillo, José L.
Object Type: Photograph
System: The Portal to Texas History