Establishment of the International Power Institute (open access)

Establishment of the International Power Institute

Building on the two previous trips to Central America last year, International Power Institute (IPI) and its partner Tennessee Valley Infrastructure Group (TVIG) have focused their attention this quarter on project sites in Honduras. TVIG's unit--an Integrated Infrastructure Platform or IIP--combines water and electricity production in a single integrated unit, thereby providing both products at a lower cost than could be attained for each one separately. Because of the unmet demand for clean drinking water and electricity in remote towns throughout the developing world, the need for such units is widespread. Previous visits to Honduras have resulted in strong in-country commercial interest, support in the form of memorandums of understanding by key government agencies, and identification of four prospective project sites for IIP installations. From March 5 to March 15 and with IPI support and participation, representatives from the TVIG, Tennessee Valley Authority (TVA), IPI, and market research firm International Business Initiatives (IBI) conducted an intensive survey of project opportunities in the four communities, to establish how IIPs might help these four communities enhance their economic development, A key aspect of the projects examined is the need to make them economically self-supporting so that they will be viable in the …
Date: April 29, 2000
Creator: Coles, Julius E.
Object Type: Report
System: The UNT Digital Library
Age constraints on fluid inclusions in calcite at Yucca Mountain (open access)

Age constraints on fluid inclusions in calcite at Yucca Mountain

The {sup 207}Pb/{sup 235}U ages for 14 subsamples of opal or chalcedony layers younger than calcite formed at elevated temperature range between 1.88 {+-} 0.05 and 9.7 {+-} 1.5 Ma with most values older than 6-8 Ma. These data indicate that fluids with elevated temperatures have not been present in the unsaturated zone at Yucca Mountain since about 1.9 Ma and most likely since 6-8 Ma. Discordant U-Pb isotope data for chalcedony subsamples representing the massive silica stage in the formation of the coatings are interpreted using a model of the diffusive loss of U decay products. The model gives an age estimate for the time of chalcedony formation around 10-11 Ma, which overlaps ages of clay minerals formed in tuffs below the water table at Yucca Mountain during the Timber Mountain thermal event.
Date: April 29, 2001
Creator: Neymark, Leonid A.; Amelin, Yuri V.; Paces, James B.; Peterman, Zell E. & Whelan, Joseph F.
Object Type: Article
System: The UNT Digital Library
Evidence for an unsaturated-zone origin of secondary minerals in Yucca Mountain, Nevada (open access)

Evidence for an unsaturated-zone origin of secondary minerals in Yucca Mountain, Nevada

The unsaturated zone (UZ) in Miocene-age welded tuffs at Yucca Mountain, Nevada, is under consideration as a potential site for the construction of a high-level radioactive waste repository. Secondary calcite and silica minerals deposited on fractures and in cavities in the UZ tuffs are texturally, isotopically, and geochemically consistent with UZ deposition from meteoric water infiltrating at the surface and percolating through the UZ along fractures. Nonetheless, two-phase fluid inclusions with small and consistent vapor to liquid (V:L) ratios that yield consistent temperatures within samples and which range from about 35 to about 80 C between samples have led some to attribute these deposits to formation from upwelling hydrothermal waters. Geochronologic studies have shown that calcite and silica minerals began forming at least 10 Ma and continued to form into the Holocene. If their deposition were really from upwelling water flooding the UZ, it would draw into question the suitability of the site as a waste repository.
Date: April 29, 2001
Creator: Whelan, Joseph F.; Roedder, Edwin & Paces, James B.
Object Type: Article
System: The UNT Digital Library
Geochemical homogeneity of tuffs at the potential repository level, Yucca Mountain, Nevada (open access)

Geochemical homogeneity of tuffs at the potential repository level, Yucca Mountain, Nevada

In a potential high-level radioactive waste repository at Yucca Mountain, Nevada, radioactive waste and canisters, drip shields protecting the waste from seepage and from rock falls, the backfill and invert material of crushed rock, the host rock, and water and gases contained within pores and fractures in the host rock together would form a complex system commonly referred to as the near-field geochemical environment. Materials introduced into the rock mass with the waste that are designed to prolong containment collectively are referred to as the Engineered Barrier System, and the host rock and its contained water and gases compose the natural system. The interaction of these component parts under highly perturbed conditions including temperatures well above natural ambient temperatures will need to be understood to assess the performance of the potential repository for long-term containment of nuclear waste. The geochemistry and mineralogy of the rock mass hosting the emplacement drifts must be known in order to assess the role of the natural system in the near-field environment. Emplacement drifts in a potential repository at Yucca Mountain would be constructed in the phenocryst-poor member of the Topopah Spring Tuff which is composed of both lithophysal and nonlithophysal zones. The chemical composition …
Date: April 29, 2001
Creator: Peterman, Zell E. & Cloke, Paul
Object Type: Article
System: The UNT Digital Library
Hydrologic characteristics of faults at Yucca Mountain, Nevada (open access)

Hydrologic characteristics of faults at Yucca Mountain, Nevada

Yucca Mountain is under study as a potential site for underground storage of high-level radioactive waste, with the principle goal being the safe isolation of the waste from the accessible environment. This paper addresses the hydrogeologic characteristics of the fault zones at Yucca Mountain, focusing primarily on the central part of the mountain where the potential repository block is located.
Date: April 29, 2001
Creator: Dickerson, Robert P.
Object Type: Article
System: The UNT Digital Library
Pore-water isotopic compositions and unsaturated-zone flow, Yucca Mountain, Nevada (open access)

Pore-water isotopic compositions and unsaturated-zone flow, Yucca Mountain, Nevada

Isotopic compositions of core-water samples from boreholes USW SD-6 and USW WT-24 indicate that recent water has been introduced at depth. Tritium, carbon, oxygen, and deuterium isotopic compositions all support younger water at depth in the two boreholes. Peaks in tritium concentrations in pore-water samples, indicating younger water than the other samples, observed near the basal vitrophyre of the Topopah Spring Tuff and at the bottom of the CHF and the top of the PP in both boreholes SD-6 and WT-24. Larger {sup 14}C activities in two pore-water samples from WT-24 at the bottom of the CHF and the top of the PP indicate younger water than in other samples from WT-24. More positive {delta}{sup 18}O and {delta}D values indicate younger water in samples of pore water at the bottom of the CHF in boreholes SD-6 and WT-24. The isotopic compositions indicating younger water at depth in boreholes SD-6 and WT-24 occur at the basal vitrophyre zone of the Topopah Spring Tuff and the bottom of the CHF/upper part of the PP, probably from lateral preferential flow through connected fractures (fast-flow paths). The source of the young water at borehole WT-24 probably was recharge from The Prow to the north, …
Date: April 29, 2001
Creator: Yang, In C.
Object Type: Article
System: The UNT Digital Library
Strontium isotope evolution of pore water and calcite in the Topopah Spring Tuff, Yucca Mountain, Nevada (open access)

Strontium isotope evolution of pore water and calcite in the Topopah Spring Tuff, Yucca Mountain, Nevada

Pore water in the Topopah Spring Tuff has a narrow range of {delta}{sup 87}Sr values that can be calculated from the {delta}{sup 87}Sr values of the rock considering advection through and reaction with the overlying nonwelded tuffs of the PTn. This model can be extended to estimate the variation of {delta}{sup 87}Sr in the pore water through time; this approximates the variation of {delta}{sup 87}Sr measured in calcite fracture coatings. In samples of calcite where no silica can be dated by other methods, strontium isotope data may be the only method to determine ages. In addition, other Sr-bearing minerals in the calcite and opal coatings, such as fluorite, may be dated using the same model.
Date: April 29, 2001
Creator: Marshall, Brian D. & Futa, Kiyoto
Object Type: Article
System: The UNT Digital Library
Use of thermal data to estimate infiltration, Yucca Mountain, Nevada (open access)

Use of thermal data to estimate infiltration, Yucca Mountain, Nevada

Temperature and pressure monitoring in a vertical borehole in Pagany Wash, Yucca Mountain, Nevada, measured disruptions of the natural gradients associated with the February, 1998, El Nino precipitation events. The temperature and pressure disruptions indicated infiltration and percolation through the 12.1 m of Pagany Wash alluvium and deep percolation to greater than 35.2 m into the Yucca Mountain Tuff.
Date: April 29, 2001
Creator: LeCain, Gary D. & Kurzmack, Mark
Object Type: Article
System: The UNT Digital Library
Water-table fluctuations in the Amargosa Desert, Nye County, Nevada (open access)

Water-table fluctuations in the Amargosa Desert, Nye County, Nevada

Pleistocene ground-water discharge deposits approximately 20 km southwest of Yucca Mountain were previously thought to represent pluvial water-table rises of 80 to 120 m. Data from new boreholes at two of the three discharge sites indicate that the modern water-table is at depths of only 17 to 30 m and that this shallow water is part of the regional ground-water flow system rather than being perched. Calcite in equilibrium with this modern ground water would have isotopic compositions similar to those in Pleistocene calcite associated with the discharge deposits. Carbon and uranium isotopes in both ground water and discharge deposits imply that past discharge consisted of a mixture of both shallow and deep ground water. These data limit Pleistocene water-table fluctuations at the specified Amargosa Desert discharge sites to between 17 and 30 m and eliminate the need to invoke large water-table rises.
Date: April 29, 2001
Creator: Paces, James B. & Whelan, Joseph
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Facilities Newsletter, April 2002. (open access)

Atmospheric Radiation Measurement Program Facilities Newsletter, April 2002.

Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.
Date: April 29, 2002
Creator: Atmospheric Radiation Measurement Program (U.S.)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
CAPACITIVE TOMOGRAPHY FOR THE LOCATION OF PLASTIC PIPE (open access)

CAPACITIVE TOMOGRAPHY FOR THE LOCATION OF PLASTIC PIPE

Throughout the utility industry, there is high interest in subsurface imaging of plastic, ceramic, and metallic objects because of the cost, reliability, and safety benefits available in avoiding impacts with the existing infrastructure and in reducing inappropriate excavations. Industry interest in locating plastic pipe has resulted in funding available for the development of technologies that enable this imaging. Gas Technology Institute (GTI) proposes to develop a compact and inexpensive capacitive tomography imaging sensor that takes the form of a flat plate or flexible mat that can be placed on the ground to image objects embedded in the soil. A compact, low-cost sensor that can image objects through soil could be applied to multiple operations and will produce a number of cost savings for the gas industry. In a stand-alone mode, it could be used to survey an area prior to excavation. The technology would improve the accuracy and reliability of any operation that involves excavation by locating or avoiding buried objects. An accurate subsurface image of an area will enable less costly keyhole excavations and other cost-saving techniques. Ground penetrating radar (GPR) has been applied to this area with limited success. Radar requires a high-frequency carrier to be injected into …
Date: April 29, 2002
Creator: Huber, Brian J.
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. IRT, 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 there are 15 ZIP genes in the Arabidopsis 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 respond differentially to metal deficiencies. For example, IRT1, ZIP6 and ZIP9 mRNA are …
Date: April 29, 2002
Creator: Geurinot, Mary Lou & Eide, David
Object Type: Report
System: The UNT Digital Library
Cryogenic Treatment of Production Components in High-Wear Rate Wells (open access)

Cryogenic Treatment of Production Components in High-Wear Rate Wells

Deep Cryogenic Tempering (DCT) is a specialized process whereby the molecular structure of a material is ''re-trained'' through cooling to -300 F and then heating to +175-1100 F. Cryocon, Inc. (hereafter referred to as Cryocon) and RMOTC entered an agreement to test the process on oilfield production components, including rod pumps, rods, couplings, and tubing. Three Shannon Formation wells were selected (TD about 500 ft) based on their proclivity for high component wear rates. Phase 1 of the test involved operation for a nominal 120 calendar day period with standard, non-treated components. In Phase 2, treated components were installed and operated for another nominal 120 calendar day period. Different cryogenic treatment profiles were used for components in each well. Rod pumps (two treated and one untreated) were not changed between test phases. One well was operated in pumped-off condition, resulting in abnormal wear and disqualification from the test. Testing shows that cryogenic treatment reduced wear of rods, couplers, and pump barrels. Testing of production tubing produced mixed results.
Date: April 29, 2002
Creator: Milliken, M.
Object Type: Report
System: The UNT Digital Library
DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW (open access)

DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW

This report presents a brief overview of the activities and tasks accomplished during the first half year (October 1, 2001--March 31, 2002) of the fifth project year budget period (October 1, 2001--September 30, 2002). An executive summary is presented initially followed by the tasks of the current budget period. Then, detailed description of the experimental and modeling investigations are presented. Subsequently, the technical and scientific results of the activities of this project period are presented with some discussions. The findings of this investigation are summarized in the ''Conclusions'' section followed by relevant references. The fifth project year activities are divided into three main parts, which are carried out in parallel. The first part is continuation of the experimental program that includes a study of the oil/water two-phase behavior at high pressures and control system development for the two-phase LLCC{copyright}. This investigation has been extended for three-phase GLCC as well. The second part consists of the development of a simplified mechanistic model incorporating the experimental results and behavior of dispersion of oil in water and water in oil. This will provide an insight into the hydrodynamic flow behavior and serve as the design tool for the industry. Although useful for sizing …
Date: April 29, 2002
Creator: Mohan, Dr. Ram S. & Shoham, Dr. Ovadia
Object Type: Report
System: The UNT Digital Library
Design Evolution Study Thermal Operating Methodology (open access)

Design Evolution Study Thermal Operating Methodology

This study provides results supporting the conclusion that the repository can be operated over a varying range of thermal modes and therefore temperatures. In particular, this work focused on limiting the peak, postclosure waste package surface temperature to less than 85 degrees Celsius, a possible limit due to corrosion considerations. These operating modes were compared by varying the waste package in drift spacing (0.1-2.83 meters), drift pitch (drift spacing centerline to centerline of 40-120 meters), ventilation duration (75-300 years), and ventilation efficiency (50-80%). The resulting graphical representation shows where the constant temperature of the waste package (85 degrees Celsius) lies with respect to drift pitch and waste package spacing. The waste considered in this study is the strict youngest fuel first 5 years old fuel. Using only strict youngest fuel first 5 years old fuel in the waste stream results in an average heat load per waste package of 12.48kW/Pkg. With this high average heat load, it is not possible to achieve a maximum waste package surface temperature of 85 degrees Celsius or less. By aging 63% of the strict youngest fuel first 5 years old fuel for 27 years, it becomes possible to maintain the waste package surface temperature …
Date: April 29, 2002
Creator: Mitchell, T.L.
Object Type: Report
System: The UNT Digital Library
Developing Continuous SCM/CRM Forcing Using NWP Products Constrained by ARM Observations (open access)

Developing Continuous SCM/CRM Forcing Using NWP Products Constrained by ARM Observations

None
Date: April 29, 2002
Creator: Xie, Shaocheng; Cederwall, R. T.; Yio, J. & Zhang, M.
Object Type: Report
System: The UNT Digital Library
Development of Large-Aperture, Light-Weight Fresnel Lenses for Gossamer Space Telescopes (open access)

Development of Large-Aperture, Light-Weight Fresnel Lenses for Gossamer Space Telescopes

In order to examine more distant astronomical objects, with higher resolution, future space telescopes require objectives with significantly larger aperture than presently available. NASA has identified a progression in size from the 2.4m aperture objective currently used in the HUBBLE space telescope[l,2], to 25m and greater in order to observe, e.g., extra-solar planets. Since weight is a crucial factor for any object sent into space, the relative weight of large optics over a given area must be reduced[3]. The areal mass density of the primary mirror for the Hubble space telescope is {approx}200 kg/m{sup 2}. This is expected to be reduced to around 15 kg/m{sup 2} for the successor to Hubble--the next generation space telescope (NGST)[4]. For future very large aperture telescopes needed for extra-solar planet detection, the areal mass density must be reduced even further. For example, the areal mass density goal for the Gossamer space telescopes is < 1 kg/m{sup 2}. The production of lightweight focusing optics at >10m size is also an enabling technology for many other applications such as Earth observation, power beaming, and optical communications.
Date: April 29, 2002
Creator: Sham, D; Hyde, R; Weisberg, A; Early, J; Rushford, M & Britten, J
Object Type: Article
System: The UNT Digital Library
Development of nondestructive evaluation methods for ceramic coatings. (open access)

Development of nondestructive evaluation methods for ceramic coatings.

Various nondestructive evaluation (NDE) technologies are being developed to study the use of ceramic coatings on components in the hot-gas path of advanced low-emission gas-fired turbines. The types of ceramic coatings include thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs). TBCs are under development for vanes, blades, and combustor liners to allow hotter gas-path temperatures, and EBCs are under development to reduce environmental damage to high-temperature components made of ceramic matrix composites. The NDE methods will be used to (a) provide data to assess the reliability of new coating application processes, (b) identify defective components that could cause unscheduled outages, (c) track growth rates of defects during component use in engines, and (d) allow rational judgment for replace/repair/re-use decisions regarding components. Advances in TBC application, both electron beam-physical vapor deposition (EB-PVD) and air plasma spraying (APS), are allowing higher temperatures in the hot-gas path. However, as TBCs become ''prime reliant,'' their condition at scheduled or unscheduled outages must be known. NDE methods are under development to assess the condition of the TBC for pre-spall conditions. EB-PVD test samples with up to 70 thermal cycles have been studied by a newly developed method involving polarized laser back-scatter NDE. Results suggest …
Date: April 29, 2002
Creator: Ellingson, W. A.; Deemer, C.; Sun, J. G.; Erdman, S.; Muliere, D. & Wheeler, B.
Object Type: Article
System: The UNT Digital Library
Extended defects and polarity of hydride vapor phase epitaxy GaN (open access)

Extended defects and polarity of hydride vapor phase epitaxy GaN

None
Date: April 29, 2002
Creator: Jasinski, J. & Liliental-Weber, Z.
Object Type: Article
System: The UNT Digital Library
FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL (open access)

FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period October 1, 2001 through March 31, 2002. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO{sub X} selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Corporation is the prime contractor. This is the fifth reporting period for the subject Cooperative Agreement. During the previous (fourth) period, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant) and a byproduct magnesium hydroxide slurry (at …
Date: April 29, 2002
Creator: Blythe, Gary M.
Object Type: Report
System: The UNT Digital Library
A Guide to Microsoft Active Directory (AD) Design (open access)

A Guide to Microsoft Active Directory (AD) Design

The goal of this paper is to facilitate the design process for those DOE sites that are currently engaged in designing their Active Directory (AD) network. It is a roadmap to enable analysis of the complicated design tradeoffs associated with Active Directory Design. By providing discussion of Active Directory design elements which are permanent and costly to change once deployed, the hope is to minimize the risks of sponsoring failed designs, or joining existing infrastructures not suitable to programmatic needs. Specifically, most Active Directory structures will fall under one of three common designs: Single Domain, Single Forest with Multiple Domains, or Multiple Forests. Each has benefits and concerns, depending on programmatic and organizational structures. The comparison of these three approaches will facilitate almost any Active Directory design effort. Finally, this paper describes some best practices to consider when designing Active Directory based on three years of research and experience.
Date: April 29, 2002
Creator: Dias, J
Object Type: Text
System: The UNT Digital Library
Inclined substrate pulsed laser deposition of YBCO thin films on polycrystalline Ag substrates. (open access)

Inclined substrate pulsed laser deposition of YBCO thin films on polycrystalline Ag substrates.

None
Date: April 29, 2002
Creator: Li, M.; Ma, B.; Koritala, R. E.; Fisher, B. L.; Dorris, S. E.; Venkataraman, K. et al.
Object Type: Article
System: The UNT Digital Library
METHANE de-NOX FOR UTILITY PC BOILERS (open access)

METHANE de-NOX FOR UTILITY PC BOILERS

The project seeks to develop and validate a new pulverized coal combustion system to reduce utility PC boiler NOx emissions to 0.15 lb/million Btu or less without post-combustion flue gas cleaning. Work during previous reporting periods completed the design, installation, shakedown and initial PRB coal testing of a 3-million Btu/h pilot system at BBP's Pilot-Scale Combustion Facility (PSCF) in Worcester, MA. Based on these results, modifications to the gas-fired preheat combustor and PC burner were defined, along with a modified testing plan and schedule. During the current reporting period, BBP's subcontract was modified to reflect changes in the pilot testing program, and the modifications to the gas-fired preheat combustor were completed. The Computational Fluid Dynamics (CFD) modeling approach was defined for the combined PC burner and 3-million Btu/h pilot system. Modeling of the modified gas-fired preheat combustor was also started.
Date: April 29, 2002
Creator: Rabovitser, Joseph; Bryan, Bruce; Nester, Serguei & Wohadlo, Stan
Object Type: Report
System: The UNT Digital Library
Model compound study of the pathways for aromatic hydrocarbon formation in soot. (open access)

Model compound study of the pathways for aromatic hydrocarbon formation in soot.

To explore the mechanisms for formation of aromatic hydrocarbons as precursors to soot, a model system using combustion of biphenyl in a fuel rich flame is studied. The soots acquired at three different temperatures are solvent extracted and the extract characterized by both GCMS and high resolution mass spectrometry. A description of the NMR results for the whole soots has been published (1). The production of most products could be rationalized from the coupling of biphenyls and subsequent aromatic species and the addition of acetylenes to existing aromatic molecules. Early work by Badger on pyrolysis of hydrocarbons is used in developing these schemes (2). The reaction schemes to produce larger aromatic hydrocarbons will be discussed. Richter and Howard have discussed in detail potential reaction mechanisms in the formation of aromatics as precursors to soot (3).
Date: April 29, 2002
Creator: Tomczyk, N. A.; Hunt, J. E.; Winans, R. E.; Solum, M. S.; Pugmire, R. J. & Fletcher, T. H.
Object Type: Article
System: The UNT Digital Library