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Altus Times (Altus, Okla.), Vol. 100, No. 245, Ed. 1 Friday, December 31, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 245, Ed. 1 Friday, December 31, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 1999
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 53, Ed. 1 Friday, December 31, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 53, Ed. 1 Friday, December 31, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: December 31, 1999
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 94, No. 105, Ed. 1 Friday, December 31, 1999 (open access)

The Boerne Star (Boerne, Tex.), Vol. 94, No. 105, Ed. 1 Friday, December 31, 1999

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: December 31, 1999
Creator: Keasling, Edna & Fierro, Jennifer
Object Type: Newspaper
System: The Portal to Texas History

[Broadcast on New Year's Eve]

Photograph of a man broadcasting on New Year's Eve 1999 for KTVT in Dallas, Texas. The man is standing on a platform in front of a video camera and is wearing a suit with a bowtie. Two news crew members can be seen; one standing next to the camera and one standing next to the platform.
Date: December 31, 1999
Creator: Williams, Byrd M. (Byrd Moore), IV, 1951-
Object Type: Photograph
System: The UNT Digital Library
Case Studies of integrated hydrogen systems. International Energy Agency Hydrogen Implementing Agreement, Final report for Subtask A of task 11 - Integrated Systems (open access)

Case Studies of integrated hydrogen systems. International Energy Agency Hydrogen Implementing Agreement, Final report for Subtask A of task 11 - Integrated Systems

Within the framework of the International Energy Agency Hydrogen Implementing Agreement, Task 11 was undertaken to develop tools to assist in the design and evaluation of existing and potential hydrogen demonstration projects. Emphasis was placed on integrated systems, from input energy to hydrogen end use. Included in the PDF document are the Executive Summary of the final report and the various case studies. The activities of task 11 were focused on near- and mid-term applications, with consideration for the transition from fossil-based systems to sustainable hydrogen energy systems. The participating countries were Canada, Italy, Japan, the Netherlands, Spain, Switzerland and the United States. In order for hydrogen to become a competitive energy carrier, experience and operating data need to be generated and collected through demonstration projects. A framework of scientific principles, technical expertise, and analytical evaluation and assessment needed to be developed to aid in the design and optimization of hydrogen demonstration projects to promote implementation. The task participants undertook research within the framework of three highly coordinated subtasks that focused on the collection and critical evaluation of data from existing demonstration projects around the world, the development and testing of computer models of hydrogen components and integrated systems, and …
Date: December 31, 1999
Creator: Schucan, T.
Object Type: Report
System: The UNT Digital Library
A Chaotic-Dynamical Conceptual Model to Describe Fluid flow and Contaminant Transport in a Fractured Vadose zone (open access)

A Chaotic-Dynamical Conceptual Model to Describe Fluid flow and Contaminant Transport in a Fractured Vadose zone

(1) To determine if and when dynamical chaos theory can be used to investigate infiltration of fluid and contaminant transport in heterogeneous soils and fractured rocks. (2) To introduce a new approach to the multiscale characterization of flow and transport in fractured basalt vadose zones and to develop physically based conceptual models on a hierarchy of scales. The following activities are indicative of the success in meeting the project s objectives: A series of ponded infiltration tests, including (1) small-scale infiltration tests (ponded area 0.5 m2) conducted at the Hell s Half Acre site near Shelley, Idaho, and (2) intermediate-scale infiltration tests (ponded area 56 m2) conducted at the Box Canyon site near Arco, Idaho. Laboratory investigations and modeling of flow in a fractured basalt core. A series of small-scale dripping experiments in fracture models. Evaluation of chaotic behavior of flow in laboratory and field experiments using methods from nonlinear dynamics; Evaluation of the impact these dynamics may have on contaminant transport through heterogeneous fractured rocks and soils, and how it can be used to guide remediation efforts; Development of a conceptual model and mathematical and numerical algorithms for flow and transport that incorporate (1) the spatial variability of heterogeneous …
Date: December 31, 1999
Creator: Faybishenko, Boris; Doughty, Christine; Stoops, Thomas M.; Wood, thomas R. & Wheatcraft, Stephen W.
Object Type: Report
System: The UNT Digital Library
Characterization of a new family of metal transporters (open access)

Characterization of a new family of metal transporters

Metal ions are critical nutrients, yet overaccumulation of these same metals can also be toxic. To maintain appropriate intracellular levels, cells require specific metal uptake systems that are subject to precise homeostatic regulation. The long-range goal of our research is to define the molecular mechanism(s) and regulation of metal ion uptake in eukaryotic cells. Integrating genetic, molecular biological and biochemical approaches, we have examined these processes in the yeast Saccharomyces cerevisiae and the plant Arabidopsis thaliana. Both are proven model systems for studying fundamental cellular processes. Our work has focused on the ZIP family of metal transporters which we identified; this family has representatives in bacteria, fungi,plants and animals. IRT1, one of the founding members of the ZIP family, is an essential cation transporter that is expressed in the epidermal cells of iron deficient plant roots and is responsible for uptake of iron from the soil. We now know that t here are 15 ZIP genes in the Arabidopsis genome which can be divided into four different classes, based on their intron/exon arrangements and the similarities among their encoded gene products. The ZIP family members display different substrate specificities for metals and different tissue distributions in Arabidopsis.Moreover, the family members …
Date: December 31, 1999
Creator: Guerinot, Mary L. & Dide, David
Object Type: Report
System: The UNT Digital Library
Chemical Decomposition of High-Level Nuclear Waste Storage/Disposal Glasses Under Irradiation (open access)

Chemical Decomposition of High-Level Nuclear Waste Storage/Disposal Glasses Under Irradiation

In the United States alone there are 100 million gallons of high-level nuclear wastes (HLWs) in various chemical forms awaiting eventual disposal in geologic repositories. For safety in handling and transport from their present underground storage tanks to their final burial sites, much of the HLWs are being immobilized by vitrification. A further virtue of HLW vitrification is the fact that the glass may serve as an additional, non-geologic barrier to the dispersal of these radio-toxins into the environment. For this reason, one of the criteria for selecting HLW glass compositions has been chemical durability against attack by ground water. While the effects of radiation on chemical durability have therefore been studied extensively, little consideration has been given to the possibility that self-irradiation of HLW glasses may lead to modes of chemical decomposition which render them unstable even in the absence of exposure to ground water. The worst-case threat would occur if the HLW glasses were to respond to irradiation in ways analogous to rock salt (NaCl). It has long been known that alkali halides irradiated to
Date: December 31, 1999
Creator: Griscom, David L. & Merzbacher, Celia I.
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 104, No. 105, Ed. 1 Friday, December 31, 1999 (open access)

The Clifton Record (Clifton, Tex.), Vol. 104, No. 105, Ed. 1 Friday, December 31, 1999

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: December 31, 1999
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
CO2 SEQUESTRATION AND RECYCLE BY PHOTOCATALYSIS WITH VISIBLE LIGHT (open access)

CO2 SEQUESTRATION AND RECYCLE BY PHOTOCATALYSIS WITH VISIBLE LIGHT

Photocatalysis could provide a cost-effective route to recycle CO{sub 2} to useful chemicals or fuels. Development of an effective catalyst for the photocatalytic synthesis requires (i) the knowledge of the surface band gap and its relation to the surface structure, (ii) the reactivity of adsorbates and their reaction pathways, and (iii) the ability to manipulate the actives site for adsorption, surface reaction, and electron transfer. The research tasks accomplished during first six months include setting up a photo-catalytic reactor, optical bench, calibration of gas chromatograph, catalyst preparation, and catalyst screening study. Addition of Pt and Cu on TiO{sub 2} was found to increase the activity of TiO{sub 2} catalysts for the synthesis of methanol and methane. The most active catalysts obtained from this study will be used for mechanistic study. The overall goal of this research is to provide a greater predictive capability for the design of visible light-photosynthesis catalysts by a deeper understanding of the reaction kinetics and mechanism as well as by better control of the coordination/chemical environment of active sites.
Date: December 31, 1999
Creator: Chuang, Steven S.C.
Object Type: Report
System: The UNT Digital Library
Colloidal Agglomerates in Tank Sludge: Impact on Waste Processing (open access)

Colloidal Agglomerates in Tank Sludge: Impact on Waste Processing

Disposal of millions of gallons of existing radioactive wastes in underground storage tanks is a major remediation activity for the United States Department of Energy. These wastes include a substantial volume of insoluble sludges consisting of submicron colloidal particles. Processing these sludges under the proposed processing conditions presents unique challenges in retrieval, transport, separation, and solidification of these waste streams. Depending on processing conditions, these colloidal particles can form agglomerated networks having high viscosities that could clog transfer lines or produce high volumes of low-density sediments that interfere with solid-liquid separations. Under different conditions, these particles can be dispersed to form very fine suspended particles that do not settle. Given the wide range of waste chemistries present at Department of Energy sites, it is impractical to measure the properties of all treatment procedures. The underlying principle s of colloid chemistry and physics were studied to provide data that would make it possible to predict and eventually control the physical properties of sludge suspensions and sediment layers in tank wastes and other waste processing streams.
Date: December 31, 1999
Creator: Tingey, Joel M.; Berg, John D.; Keefer, K. D.; Lea, A. S.; Rector, D. R.; Virden, J. W. et al.
Object Type: Report
System: The UNT Digital Library
Combustion 2000 (open access)

Combustion 2000

This report presents work carried out under contract DE-AC22-95PC95144 ''Combustion 2000 - Phase II.'' The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) that is capable of: {lg_bullet} thermal efficiency (HHV) {ge} 47% {lg_bullet} NOx, SOx, and particulates {le} 10% NSPS (New Source Performance Standard) {lg_bullet} coal providing {ge} 65% of heat input {lg_bullet} all solid wastes benign {lg_bullet} cost of electricity {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 and …
Date: December 31, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Cooled silicon nitride stationary turbine vane risk reduction. Final report (open access)

Cooled silicon nitride stationary turbine vane risk reduction. Final report

The purpose of this program was to reduce the technical risk factors for demonstration of air cooled silicon nitride turbine vanes. The effort involved vane prototype fabrication efforts at two U.S. based gas turbine grade silicon nitride component manufacturers. The efficacy of the cooling system was analyzed via a thermal time/temperature flow test technique previously at UTRC. By having multiple vendors work on parts fabrication, the chance of program success increased for producing these challenging components. The majority of the effort under this contract focused on developing methods for, and producing, the complex thin walled silicon nitride vanes. Components developed under this program will undergo engine environment testing within N00014-96-2-0014.
Date: December 31, 1999
Creator: Holowczak, John
Object Type: Report
System: The UNT Digital Library

[Dallas Police Conversing with a Woman]

Photograph of two Dallas Police officers conversing with a woman on New Year's Eve 1999 in Dallas, Texas. The woman is sitting on a platform that contains news broadcasting equipment. Other news staff are standing on the platform behind the woman.
Date: December 31, 1999
Creator: Williams, Byrd M. (Byrd Moore), IV, 1951-
Object Type: Photograph
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 16, No. 35, Ed. 1 Friday, December 31, 1999 (open access)

Dallas Voice (Dallas, Tex.), Vol. 16, No. 35, Ed. 1 Friday, December 31, 1999

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: December 31, 1999
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
Determination of Transmutation Effects in Crystalline Waste Forms (open access)

Determination of Transmutation Effects in Crystalline Waste Forms

The overall goal of this Environmental Management Science Program project was to develop research tools to investigate the effect of transmutation, that is, the radioactive decay of a radioisotope to an isotope of another element, on the stability of a crystalline matrix. This process is an important issue in the assessment of the long-term stability, and hence performance, of a waste form. Most work on radiation effects in waste forms has focused on alpha radiation, which produces more displacements than beta radiation. However, beta radiation results in transmutation, which changes both the valence and the ionic radius of the element undergoing decay. These changes in coordination chemistry may destabilize the waste form and hence permit higher releases of the radionuclide contaminants to the accessible environment. Little is known about the mobility of Cs in pollucite. Only a few studies [1-3] have examined leaching following transmutation or irradiation of pollucite or closely related aluminosilicates. These studies seem to have contradictory results. The results may indicate that prior to radiation-induced amorphization, the accumulated defects may lead to higher leachability of Cs [3], whereas once amorphization occurs, the Cs becomes trapped in the collapsed structure [2]. A more thorough analysis of the effect …
Date: December 31, 1999
Creator: Fortner, Jeffrey A.
Object Type: Report
System: The UNT Digital Library
Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste (open access)

Development of a High Fluence Neutron Source for Nondestructive Characterization of Nuclear Waste

We are addressing the need to measure nuclear wastes, residues, and spent fuel in order to process these for final disposition. For example, TRU wastes destined for the WIPP must satisfy extensive characterization criteria outlined in the Waste Acceptance Criteria, the Quality Assurance Program Plan, and the Performance Demonstration Plan. Similar requirements exist for spent fuel and residues. At present, no nondestructive assay (NDA) instrumentation is capable of satisfying all of the PDP test cycles (particularly for Remote-Handled TRU waste). One of the primary methods for waste assay is by active neutron interrogation. The objective of this project is to improve the capability of all active neutron systems by providing a higher intensity neutron source (by about a factor of 1,000) for essentially the same cost, power, and space requirements as existing systems. This high intensity neutron source is an electrostatically confined (IEC) plasma device. The IEC is a symmetric sphere that was originally developed in the 1960s as a possible fusion reactor. It operates as DT neutron generator. Although it is not likely that this device will scale to fusion reactor levels, previous experiments1 have demonstrated a neutron yield of 2 x 1010 neutrons/second on a table-top device that …
Date: December 31, 1999
Creator: Pickrell, Mark M.
Object Type: Report
System: The UNT Digital Library
Development of METHANE de-NOX reburning process. Quarterly report, October 1 - December 31, 1999 (open access)

Development of METHANE de-NOX reburning process. Quarterly report, October 1 - December 31, 1999

The use of biomass and wood waste solids and sludges as fuel is often hampered by their low heating values and the presence of bound nitrogen that result in inefficient combustion and high NOx emission. Cofiring supplemental fuel through auxiliary burners helps with improving the combustion effectiveness and NOx reduction, but the benefits are limited to the fractional heat input of the auxiliary fuel. Demonstration tests have shown over 60% reduction in NOx, CO and VOC emissions, and a 2% increase in boiler thermal efficiency using only 8 to 13% natural gas.
Date: December 31, 1999
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The effects of fertilization and competition control on carbon and nutrient allocation and physiology in loblolly pine plantation. Quarterly report for the period October - December, 1999 (open access)

The effects of fertilization and competition control on carbon and nutrient allocation and physiology in loblolly pine plantation. Quarterly report for the period October - December, 1999

None
Date: December 31, 1999
Creator: Hendrick, Ronald; Will, Rodney; Teskey, Robert; Borders, Bruce; Bailey, Robert; Harrington, Timothy et al.
Object Type: Report
System: The UNT Digital Library
Engineering Development of Coal-Fired High-Performance Power Systems Progress Report: October-December 1999 (open access)

Engineering Development of Coal-Fired High-Performance Power Systems Progress Report: October-December 1999

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, 1999
Creator: Tsuo, York
Object Type: Report
System: The UNT Digital Library
Enhanced Sludge Processing of HLW: Hydrothermal Oxidation of Chromium, Technetium, and Complexants by Nitrate (open access)

Enhanced Sludge Processing of HLW: Hydrothermal Oxidation of Chromium, Technetium, and Complexants by Nitrate

The objective of this project is to develop the scientific basis for hydrothermal separation of chromium from High Level Waste (HLW) sludges. Our worked is aimed at attaining a fundamental understanding of chromium speciation, oxidation/reduction and dissolution kinetics, reaction mechanisms, and transport properties under hydrothermal conditions in both simple and complex salt solutions that will ultimately lead to an efficient chromium leaching process.
Date: December 31, 1999
Creator: Buelow, Steven J. & Robinson, Jeanne M.
Object Type: Report
System: The UNT Digital Library
Evaluation Of Isotopic Diagnostics For Subsurface Characterization And Monitoring : Field Experiments At The Tan And RWMC (SDA) Sites, Ineel (open access)

Evaluation Of Isotopic Diagnostics For Subsurface Characterization And Monitoring : Field Experiments At The Tan And RWMC (SDA) Sites, Ineel

The purpose of this project was to explore and refine applications of isotope measurements for guiding environmental remediation strategies. The isotopic compositions of samples from field sites were analyzed to address both basic scientific issues and site-specific problems. Initial efforts were concentrated on two sites at the Idaho National Engineering and Environmental Laboratory (INEEL). During the final year of the project, the focus of work was shifted to the Hanford site in Washington. The Test Area North (TAN) site at INEEL consists of a 2 km-long plume of mixed wastes containing low-level radionuclides, sewage and chlorinated solvents that were injected into the groundwater between 1955 and 1972. Isotopic measurements of groundwater samples were made to address questions about the source of the groundwater and the regional hydrology at TAN. These data show that there is a significant input to the groundwater from playa lakes that were located west of the TAN site prior to the 1950s (since that time, inflow to the playas has been diverted for agricultural uses). Radiocarbon dates of the playa waters indicate a mean infiltration rate of 3-5 cm/year. These results explain the groundwater flow patterns observed in the plume and provide constraints on transport rates.
Date: December 31, 1999
Creator: DePaolo, Donald J.
Object Type: Report
System: The UNT Digital Library
Experimental Determination of Contaminant Metal Mobility as a Function of Temperature, Time, and Solution Chemistry (open access)

Experimental Determination of Contaminant Metal Mobility as a Function of Temperature, Time, and Solution Chemistry

During the FY96-FY99 funding cycle we examined the uptake of aqueous strontium onto goethite, kaolinite, and amorphous silica surfaces as a function of pH, total strontium, and temperature. Our overall goal was to produce a mechanistic sorption model that can be used in reaction-transport calculations to predict the mobility and attenuation of radioactive strontium (90Sr) in the environment. Our approach was to combine structural information derived from synchrotron-based x-ray absorption spectroscopic analysis together with macroscopic uptake data and surface complexation models to clarify the physical and chemical structure of sorbed complexes. We chose to study these solids because of the prevalence of clays and iron hydroxides in natural systems, and because silica colloids probably form beneath leaking tanks at Hanford as caustic waste is neutralized. We have published the spectroscopic work in two papers in the Journal of Colloid and Interface Science [1, 2], and will soon submit at third manuscript to Geochemical Transactions [3] combining the sorption and spectroscopic data with a mechanistic complexation model.
Date: December 31, 1999
Creator: Carroll, Susan A. & O'Day, Peggy A.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, December 31, 1999 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, December 31, 1999

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 1999
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History