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Věstník (Temple, Tex.), Vol. 92, No. 15, Ed. 1 Wednesday, April 14, 2004
Weekly Czech and English language newspaper from Temple, Texas published as the official organ of the Slavonic Benevolent Order of the State of Texas that includes news of interest to members along with advertising.
Date:
April 14, 2004
Creator:
Vanicek, Brian
Object Type:
Newspaper
System:
The Portal to Texas History
Věstník (Temple, Tex.), Vol. 92, No. 2, Ed. 1 Wednesday, January 14, 2004
Weekly Czech and English language newspaper from Temple, Texas published as the official organ of the Slavonic Benevolent Order of the State of Texas that includes news of interest to members along with advertising.
Date:
January 14, 2004
Creator:
Vanicek, Brian
Object Type:
Newspaper
System:
The Portal to Texas History
Věstník (Temple, Tex.), Vol. 92, No. 27, Ed. 1 Wednesday, July 14, 2004
Weekly Czech and English language newspaper from Temple, Texas published as the official organ of the Slavonic Benevolent Order of the State of Texas that includes news of interest to members along with advertising.
Date:
July 14, 2004
Creator:
Vanicek, Brian
Object Type:
Newspaper
System:
The Portal to Texas History
The Tulia Herald (Tulia, Tex.), Vol. 96, No. 42, Ed. 1 Thursday, October 14, 2004
Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.
Date:
October 14, 2004
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Fuel cycle methods : first-order spherical harmonics formulations capable of treating low density regions.
In this report we present an approach to deal with a problem encountered in different type of systems and specific configurations: the treatment of low density regions. This is the case of gas cooled reactors, voided configurations (evaluations of associated reactivity coefficients), beam region of external source driven systems, etc. The approach is to form the nodal response matrix using the first-order form of the transport equation, for then the cross section no longer appears in the denominator, as in the case of the standard formulation of the VARIANT code. Two different formulations are presented: the differential and integral ones. After applications to different difficult benchmark problems, it was concluded that the new formulations can treat low density regions.
Date:
January 14, 2004
Creator:
Smith, M. A.; Palmiotti, G. & Lewis, E. E.
Object Type:
Report
System:
The UNT Digital Library
FY03 DNAPL Characterization of the A-14 Outfall
Residual dense non-aqueous phase liquid (DNAPL) contamination continues to be one of the most challenging remediation and characterization problems at SRS and sites around the world. Chlorinated solvents were usually released as DNAPLs to/the subsurface where they move in an unstable fashion driven by gravitational and,capillary forces. They are often retained in small discrete blobs in fine grain materials in the vadose zone and contaminate ground water by slow continuous release through dissolution and diffusion. Locating these small sources is a difficult but crucial part of remediating a contaminated site. Several methods have been developed to locate subsurface DNAPL but nearly all are intrusive and can only identify DNAPL in close proximity to the access hole. Minimally invasive geophysical methods to locate residual DNAPL have been proposed and developed but few methods are capable of the spatial resolution required. Complex resistivity measurements sensitive to DNAPL (perchloroethylene) interactions with clay (smectite) have recently been shown to have promise in laboratory experiments. Based on these laboratory results, field tests of the complex resistivity technique were performed at the A-014 outfall.
Date:
January 14, 2004
Creator:
Riha, BD
Object Type:
Report
System:
The UNT Digital Library
User's guide, version 1 RESRAD-BIOTA : a tool for implementing a graded approach to biota dose evaluation.
This Interagency Steering Committee on Radiation Standards (ISCORS) Technical Report provides a User's Guide for the RESRAD-BIOTA code. The RESRAD-BIOTA code is a tool for implementing a graded approach to biota dose evaluation. The RESRAD-BIOTA code was principally sponsored and developed by the U.S. Department of Energy (DOE), with support from the U.S. Environmental Protection Agency (EPA) and the U.S. Nuclear Regulatory Commission (NRC), through the informal interagency Ecological Radiological Work Group (ECORAD-WG). The work group was led by DOE and coordinated under the oversight of ISCORS. The RESRAD-BIOTA code provides a complete spectrum of biota dose evaluation capabilities, from methods for general screening, to comprehensive receptor-specific dose estimation. The code was designed to be consistent with and provide a tool for implementing the DOE ''Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota'' (DOE voluntary consensus Technical Standard DOE-STD-1153-2002), and to provide advanced analysis capabilities in a manner that will support the anticipated needs of DOE and other agencies. These advanced analysis capabilities were generally developed through a consensus-based process among the participating agency representatives of the ECORAD-WG.
Date:
January 14, 2004
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Investigation of the Rayleigh-Taylor and Richtmyer-Meshkov instabilities
Some of the major difficulties encountered in the effort to achieve nuclear fusion by means of inertial confinement arise from the unstable behavior of the interface between the shell material and the nuclear fuel which develops upon implosion of the shell by direct or indirect laser drive. The fluid flows that develop (termed the Rayleigh-Taylor (RT) and the Richtmyer-Meshkov (RM) instabilities) cause the gassified shell material to mix with the nuclear fuel, causing a reduction in energy yield or no ignition altogether. The present research program addresses the Rayleigh-Taylor and the Richtmyer-Meshkov instabilities with extensive laboratory and computational experiments. In the past year, three new activities have been initiated: a new shock tube experiment, involving the impulsive acceleration of a test gas-filled soap bubble, diagnosed with planar Mie scattering or planar induced fluorescence; a Rayleigh-Taylor experiment based on the use of a magnetorheological (MR) fluid to fix the initial shape of the interface between the MR fluid and water; and a series of computer calculations using the Raptor code (made available by Lawrence Livermore National Laboratory) to design and simulate the shock tube experiments.
Date:
January 14, 2004
Creator:
Bonazza, Riccardo; Anderson, Mark & Smith, Leslie
Object Type:
Report
System:
The UNT Digital Library
A Hydro-Economic Approach to Representing Water Resources Impacts in Integrated Assessment Models
Grant Number DE-FG02-98ER62665 Office of Energy Research of the U.S. Department of Energy Abstract Many Integrated Assessment Models (IAM) divide the world into a small number of highly aggregated regions. Non-OECD countries are aggregated geographically into continental and multiple-continental regions or economically by development level. Current research suggests that these large scale aggregations cannot accurately represent potential water resources-related climate change impacts. In addition, IAMs do not explicitly model the flow regulation impacts of reservoir and ground water systems, the economics of water supply, or the demand for water in economic activities. Using the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT) model of the International Food Policy Research Institute (IFPRI) as a case study, this research implemented a set of methodologies to provide accurate representation of water resource climate change impacts in Integrated Assessment Models. There were also detailed examinations of key issues related to aggregated modeling including: modeling water consumption versus water withdrawals; ground and surface water interactions; development of reservoir cost curves; modeling of surface areas of aggregated reservoirs for estimating evaporation losses; and evaluating the importance of spatial scale in river basin modeling. The major findings include: - Continental or national or even …
Date:
January 14, 2004
Creator:
Kirshen, Paul H. & Strzepek, Kenneth, M.
Object Type:
Report
System:
The UNT Digital Library
Dissolution of Highly Enriched Uranium from the Idaho National Engineering and Environmental Laboratory
Since the capability to purify uranium (U) was terminated at the Idaho National Engineering and Environmental Laboratory (INEEL) in the early 1990's, excess highly enriched uranium (HEU) from the cleanout of uranium trioxide (UO3) production equipment will be shipped to the Savannah River Site (SRS) for disposition. The excess material will be dissolved in Phase I of HB-Line, purified by solvent extraction, and blended with normal U to an enrichment which can be used to fabricate fuel for Tennessee Valley Authority (TVA) reactors. The proposed HB-Line processing strategy is to dissolve up to 3 kg of material per 18 L dissolver batch. To demonstrate the proposed processing strategy, two samples of the HEU were shipped to the Savannah River Technology Center (SRTC). The material was used in a series of small-scale experiments in which prototypical amounts were dissolved to characterize the offgas and measure the dissolution time under varying process conditions. Complete dissolution of the U was obtained in 15-30 min for experiments performed at 23-60 degrees Celsius. The HEU was dissolved in 3.5M HNO3 using the solids to liquid ratio proposed for use in HB-Line. The experiment performed at 23 degrees Celsius demonstrated that rapid heat generation during the …
Date:
January 14, 2004
Creator:
Rudisill, T.S.
Object Type:
Report
System:
The UNT Digital Library
An Archaeological Evaluation of the Oak Point Park & Nature Preserve
A report of an archaeological evaluation conducted in Plano, Texas to determine whether or not locations within were suitable for prehistoric and historic occupation.
Date:
December 14, 2004
Creator:
Todd, Jesse E. & Trask, Lance K.
Object Type:
Report
System:
The Portal to Texas History
Pybus -- A Python Software Bus
A software bus, just like its hardware equivalent, allows for the discovery, installation, configuration, loading, unloading, and run-time replacement of software components, as well as channeling of inter-component communication. Python, a popular open-source programming language, encourages a modular design on software written in it, but it offers little or no component functionality. However, the language and its interpreter provide sufficient hooks to implement a thin, integral layer of component support. This functionality can be presented to the developer in the form of a module, making it very easy to use. This paper describes a Pythonmodule, PyBus, with which the concept of a ''software bus'' can be realized in Python. It demonstrates, within the context of the ATLAS software framework Athena, how PyBus can be used for the installation and (run-time) configuration of software, not necessarily Python modules, from a Python application in a way that is transparent to the end-user.
Date:
October 14, 2004
Creator:
Lavrijsen, Wim T.L.P.
Object Type:
Article
System:
The UNT Digital Library
Classroom HVAC: Improving ventilation and saving energy -- field study plan
The primary goals of this research effort are to develop, evaluate, and demonstrate a very practical HVAC system for classrooms that consistently provides classrooms (CRs) with the quantity of ventilation in current minimum standards, while saving energy, and reducing HVAC-related noise levels. This research is motivated by the public benefits of energy efficiency, evidence that many CRs are under-ventilated, and public concerns about indoor environmental quality in CRs. This document provides a summary of the detailed plans developed for the field study that will take place in 2005 to evaluate the energy and IAQ performance of a new classroom HVAC technology. The field study will include measurements of HVAC energy use, ventilation rates, and IEQ conditions in 10 classrooms with the new HVAC technology and in six control classrooms with a standard HVAC system. Energy use and many IEQ parameters will be monitored continuously, while other IEQ measurements will be will be performed seasonally. Continuously monitored data will be remotely accessed via a LonWorks network. Instrument calibration plans that vary with the type of instrumentation used are established. Statistical tests will be employed to compare energy use and IEQ conditions with the new and standard HVAC systems. Strengths of this …
Date:
October 14, 2004
Creator:
Apte, Michael G.; Faulkner, David; Hodgson, Alfred T. & Sullivan, Douglas P.
Object Type:
Report
System:
The UNT Digital Library
Involvement of Linear Plasmids in Aerobic Biodegradation of Vinyl Chloride
Pseudomonas putida strain AJ and Ochrobactrum strain TD were isolated from hazardous waste sites based on their ability to use vinyl chloride (VC) as a sole source of carbon and energy under aerobic conditions. Strains AJ and TD also use ethene and ethylene oxide as growth substrates. Strain AJ contained a linear megaplasmid (approximately 260 kb) when grown on VC or ethene, but no circular plasmids. While growing on ethylene oxide, the size of the linear plasmid in strain AJ decreased to approximately 100 kb, although its ability to use VC as a substrate was retained. The linear plasmids in strain AJ were cured and its ability to consume VC, ethene, and ethylene oxide was lost following growth on a rich substrate (Luria-Bertani broth) through at least three transfers. Strain TD contained three linear plasmids, ranging in size from approximately 100 kb to 320 kb, when growing on VC or ethene. As with strain AJ, the linear plasmids in strain TD were cured following growth on Luria -Bertani broth and its ability to consume VC and ethene was lost. Further analysis of these linear plasmids may help reveal the pathway for VC biodegradation in strains AJ and TD and explain …
Date:
June 14, 2004
Creator:
BRIGMON, ROBINL.
Object Type:
Article
System:
The UNT Digital Library
Incorporation of Integral Fuel Burnable Absorbers Boron and Gadolinium into Zirconium-Alloy Fuel Clad Material
Long-lived fuels require the use of higher enrichments of 235U or other fissile materials. Such high levels of fissile material lead to excessive fuel activity at the beginning of life. To counteract this excessive activity, integral fuel burnable absorbers (IFBA) are added to some rods in the fuel assembly. The two commonly used IFBA elements are gadolinium, which is added as gadolinium-oxide to the UO2 powder, and boron, which is applied as a zirconium-diboride coating on the UO2 pellets using plasma spraying or chemical vapor deposition techniques. The incorporation of IFBA into the fuel has to be performed in a nuclear-regulated facility that is physically separated from the main plant. These operations tend to be very costly because of their small volume and can add from 20 to 30% to the manufacturing cost of the fuel. Other manufacturing issues that impact cost and performance are maintaining the correct levels of dosing, the reduction in fuel melting point due to gadolinium-oxide additions, and parasitic neutron absorption at fuel's end-of-life. The goal of the proposed research is to develop an alternative approach that involves incorporation of boron or gadolinium into the outer surface of the fuel cladding material rather than as an …
Date:
December 14, 2004
Creator:
Sridharan, K.; Renk, T.J.; Lahoda, E.J. & Corradini, M.L
Object Type:
Report
System:
The UNT Digital Library
Hyperspectral Geobotanical Remote Sensing for CO2 Storage Monitoring
This project's goal is to develop remote sensing methods for early detection and spatial mapping, over whole regions simultaneously, of any surface areas under which there are significant CO2 leaks from deep underground storage formations. If large amounts of CO2 gas percolated up from a storage formation below to within plant root depth of the surface, the CO2 soil concentrations near the surface would become elevated and would affect individual plants and their local plant ecologies. Excessive soil CO2 concentrations are observed to significantly affect local plant and animal ecologies in our geothermal exploration, remote sensing research program at Mammoth Mountain CA USA. We also know from our geothermal exploration remote sensing programs, that we can map subtle hidden faults by spatial signatures of altered minerals and of plant species and health distributions. Mapping hidden faults is important because in our experience these highly localized (one to several centimeters) spatial pathways are good candidates for potentially significant CO2 leaks from deep underground formations. The detection and discrimination method we are developing uses primarily airborne hyperspectral, high spatial (3 meter) with 128 band wavelength resolution, visible and near infrared reflected light imagery. We also are using the newly available ''Quickbird'' satellite …
Date:
May 14, 2004
Creator:
Pickles, W & Cover, W
Object Type:
Book
System:
The UNT Digital Library
Material Property Estimation for Direct Detections of DNAPL using Integrated Ground-Penetrating Radar Velocity, Imaging and Attribute Analysis
The focus of our work is direct detection of DNAPLs, specifically chlorinated solvents, via material property estimation from surface ground-penetrating radar (GPR) data. We combine sophisticated GPR processing methodology with quantitative attribute analysis and material property estimation to determine the location and extent of residual and/or pooled DNAPL in both the vadose and saturated zones. An important byproduct of our research is state-of-the-art imaging which allows us to pinpoint attribute anomalies, characterize stratigraphy, identify fracture zones, and locate buried objects. Implementation and verification of these methodologies will be a significant advance in GPR research and in meeting DOE's need for reliable in-situ characterization of DNAPL contamination. Chlorinated solvents have much lower electric permittivity and conductivity than water. An electrical property contrast is induced when solvents displace water in the sediment column resulting in an anomalous GPR signature. To directly identify zones of DNAPL contamination, we focus on three aspects of reflected wave behavior--propagation velocity, frequency dependent attenuation, and amplitude variation with offset (AVO). Velocity analysis provides a direct estimate of electric permittivity, attenuation analysis provides a measure of conductivity, and AVO behavior is used to estimate the permittivity ratio at a reflecting boundary. Areas of anomalously low electric permittivity and …
Date:
June 14, 2004
Creator:
Bradford, John; Smithson, Scott B. & Holbrook, W. Stephen
Object Type:
Report
System:
The UNT Digital Library
Field power measurements of imaging equipment
According to the U.S. Department of Energy, electricity use by non-PC commercial office equipment is growing at an annual rate of nearly 5 percent (AEO 2003). To help address this growth in consumption, U.S. EPA periodically updates its ENERGY STAR specifications as products and markets change. This report presents background research conducted to help EPA update the ENERGY STAR specification for imaging equipment, which covers printers, fax machines, copiers, scanners, and multifunction devices (MFDs). We first estimated the market impact of the current ENERGY STAR imaging specification, finding over 90 percent of the current market complies with the specification. We then analyzed a sample of typical new imaging products, including 11 faxes, 57 printers and 19 copiers/MFD. For these devices we metered power levels in the most common modes: active/ready/sleep/off, and recorded features that would most likely affect energy consumption. Our metering indicates that for many products and speed bins, current models consume substantially less power than the current specification. We also found that for all product categories, power consumption varied most considerably across technology (i.e. inkjet vs. laser). Although inkjet printers consumed less energy than laser printers in active, ready and sleep-mode, they consumed more power on average while …
Date:
May 14, 2004
Creator:
McWhinney, Marla; Homan, Gregory; Brown, Richard; Roberson, Judy; Nordman, Bruce & Busch, John
Object Type:
Report
System:
The UNT Digital Library
Modeling Laser Effects on the Final Optics in Simulated IFE Environments
When laser light interacts with a material's surface, photons rapidly heat the electronic system, resulting in very fast energy transfer to the underlying atomic crystal structure. The intense rate of energy deposition in the shallow sub-surface layer creates atomic defects, which alter the optical characteristics of the surface itself. In addition, the small fraction of energy absorbed in the mirror leads to its global deformation by thermal and gravity loads (especially for large surface area mirrors). The aim of this research was to model the deformation of mirror surfaces at multiple length and time scales for applications in advanced Inertial Fusion Energy (IFE) systems. The goal is to control micro- and macro-deformations by material system and structural design. A parallel experimental program at UCSD has been set up to validate the modeling efforts. The main objective of the research program was to develop computer models and simulations for Laser-Induced Damage (LID) in reflective and transmissive final optical elements in IFE laser-based systems. A range of materials and material concepts were investigated and verified by experiments at UCSD. Four different classes of materials were considered: (1) High-reflectivity FCC metals (e.g. Cu, Au, Ag, and Al), (2) BCC metals (e.g. Mo, Ta …
Date:
August 14, 2004
Creator:
Ghoniem, Nasr
Object Type:
Report
System:
The UNT Digital Library
Fluorescent CdSe/ZnS nanocrystal-peptide conjugates for long-term, nontoxic imaging and nuclear targeting in living cells
One of the biggest challenges in cell biology is the imaging of living cells. For this purpose, the most commonly used visualization tool is fluorescent markers. However, conventional labels, such as organic fluorescent dyes or green fluorescent proteins (GFP), lack the photostability to allow the tracking of cellular events that happen over minutes to days. In addition, they are either toxic to cells (dyes), or difficult to construct and manipulate (GFP). We report here the use of a new class of fluorescent labels, silanized CdSe/ZnS nanocrystal-peptide conjugates, for imaging the nuclei of living cells. CdSe/ZnS nanocrystals, or so called quantum dots (qdots), are extremely photostable, and have been used extensively in cellular imaging of fixed cells. However, most of the studies about living cells so far have been concerned only with particle entry into the cytoplasm or the localization of receptors on the cell membrane. Specific targeting of qdots to the nucleus of living cells ha s not been reported in previous studies, due to the lack of a targeting mechanism and proper particle size. Here we demonstrate for the first time the construction of a CdSe/ZnS nanocrystal-peptide conjugate that carries the SV40 large T antigen nuclear localization signal (NLS), …
Date:
June 14, 2004
Creator:
Chen, Fanqing & Gerion, Daniele
Object Type:
Article
System:
The UNT Digital Library
Design and characterization of a neutralized-transport experiment for heavy-ion fusion
In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparisons of theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion Fusion has completed the construction and has begun experimentation with the Neutralized Transport Experiment (NTX). The experiment consists of three main sections, each with its own physics issues. The injector is designed to generate a very high-brightness, space-charge-dominated potassium beam while still allowing variable perveance by a beam aperturing technique. The magnetic-focusing section, consisting of four pulsed magnetic quadrupoles, permits the study of beam tuning, as well as the effects of phase space dilution due to higher-order nonlinear fields. In the final section, the converging ion beam exiting the magnetic section is transported through a drift region with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this …
Date:
March 14, 2004
Creator:
Henestroza, E.; Eylon, S.; Roy, P. K.; Yu, S. S.; Anders, A.; Bieniosek, F. M. et al.
Object Type:
Article
System:
The UNT Digital Library
ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT
As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger Data & Consulting Services (DCS) joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden & Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners previously provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify underperforming wells with remediation potential. We have enhanced and streamlined our software and are using it with the latest versions of Microsoft's{trademark} Access and Excel programs. During the last quarter of 2002, Great Lakes provided us with additional data for approximately 2,200 wells located in their Cooperstown field situated in northwestern Pennsylvania. We identified approximately 130 potential remediation candidates, and Great Lakes personnel are currently reviewing this list for viable remediation. Within the last few weeks, a list of five candidates have been chosen for refract, in addition to two alternate wells. This field has provided a rigorous test of our software and analytical methods. We have processed all the information provided to us including the Cooperstown …
Date:
July 14, 2004
Creator:
MacDonald, Ronald J.
Object Type:
Report
System:
The UNT Digital Library
The Near Elimination of Hysteresis in Pd/Cr2O3 Composites
Although its value varies with the microstructure, hysteresis always accompanies hydride formation and decomposition in Pd(pure)-H, e.g., it is present even in nano-crystalline and thin films. Internal oxidation of Pd0.93Cr0.07 alloys leads to a pure Pd matrix containing nano-crystalline chromia precipitates. The characteristic hysteresis of Pd-H almost disappears in this form of Pd. The reasons for this are discussed. Hysteresis is an almost universal feature of first order solid state transitions. Its presence means that when such a transition is reversed, it follows a different path than that taken in the forward direction leading to a loss of useful work. Hysteresis is, of course, a reflection of the irreversibility of the transition.
Date:
July 14, 2004
Creator:
SHANAHAN, KIRKL
Object Type:
Article
System:
The UNT Digital Library
Diffusion in silicon isotope heterostructures
The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the dopant diffusion mechanisms, the native defect charge states, and the self- and dopant diffusion coefficients can be determined. This information is necessary to enhance the physical modeling of dopant diffusion in Si. It is of particular interest to the modeling of future electronic Si devices, where the nanometer-scale …
Date:
May 14, 2004
Creator:
Silvestri, Hughes Howland
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library