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FY01 Phytoremediation of Chlorinated Ethenes in Southern Sector Seepline Sediments of SRS

Description: This treatability study is now in the second year of deployment for the Southern Sector Phytoremediation Project. Phytoremediation is the use of vegetation and associated media to treat contaminated soils, sediments, and groundwater. Phytoremediation is a rapidly developing technology that promises effective and safe cleanup of certain hazardous wastes. This ongoing work addresses the fate of volatile organic contaminants (VOCs) in an experiment that simulates a vegetated seepline supplied with trichloroethylene- (TCE-) and perchloroethylene- (PCE-) contaminated groundwater. The primary objective is to determine how the trees and sediments uptake groundwater TCE and PCE, biodegrade it, and/or transform it. The experimental focus of this project is the biological removal of VOCs from seepline groundwater and sediments.
Date: January 30, 2004
Creator: Brigmon, R.L.
Partner: UNT Libraries Government Documents Department
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LAW Radioactive Coupon CO{sub 2} Decontamination Test

Description: The objective of this test is to confirm that CO{sub 2} blasting is capable of effectively removing smearable contamination from the external surface of the Immobilized Low Activity Waste(ILAW) stainless steel container after glass pouring. The smearable contamination level limits specified in the approved test specification are: (1) 367 Bq/m{sup 2} (220 dpm/100 cm{sup 2}) alpha and 3670 Bq/m{sup 2} (2202 dpm/100 cm{sup 2}) beta-gamma (qualification limits); and (2) 100 dpm/100 cm{sup 2} alpha and 1000 dpm/100 cm{sup 2} beta-gamma (design limits). The removal of smearable contamination from radioactively contaminated coupon was demonstrated by varying the following operating parameters: Nozzle standoff distance; Blast air pressure; Pellet rate; and Nozzle travel speed. Coupons were weighed before and after blasting to determine if the CO{sub 2} blasting process removed measurable amounts of surface material from the coupons. High-speed photography was used to capture images of the pellets exiting the blast nozzle as a means of estimating pellet shape and velocity at the blast nozzle. Bleeding tests were performed to determine if fixed contamination remaining on coupons after blasting ''bleeds out'' and measures as smearable contamination under typical storage conditions and times. The bleeding tests consisted of storing blasted coupons with no detectable smearable contamination for a period of 92 days at 95 F. Coupons were removed at 23-day intervals and re-evaluated for smearable contamination. The radioactive coupon blasting tests consisted of four main subtasks: (1) Coupon preparation; (2) CO{sub 2} blasting; (3) High-speed photography; and (4) Bleeding tests.
Date: January 30, 2004
Creator: May, C.G.
Partner: UNT Libraries Government Documents Department
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FY02 Final Report on Phytoremediation of Chlorinated Ethenes in Southern Sector Sediments of the Savannah River Site

Description: This final report details the operations and results of a 3-year Seepline Phytoremediation Project performed adjacent to Tims Branch, which is located in the Southern Sector of the Savannah River Site (SRS) A/M Area. Phytoremediation is a process where interactions between vegetation, associated microorganisms, and the host substrate combine to effectively degrade contaminated soils, sediments, and groundwater. Phytoremediation is a rapidly developing technology that shows promise for the effective and safe cleanup of certain hazardous wastes. It has the potential to remediate numerous volatile organic compounds (VOCs). Extensive characterization work has demonstrated that two VOCs, tetrachloroethylene (PCE) and trichloroethylene (TCE) are the major components of the VOC-contaminated groundwater that is migrating through the Southern Sector and Tims Branch seepline area (WSRC, 1999). The PCE and TCE are chlorinated ethenes (CE), and have been detected in seepline soils and ground water adjacent to the ecologically-sensitive Tims Branch seepline area.
Date: January 30, 2004
Creator: Brigmon, R..L.
Partner: UNT Libraries Government Documents Department
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Gas Generation Testing of Neptunium Oxide at Elevated Temperature

Description: Elevated temperature gas generation tests have been conducted using neptunium dioxide produced on a laboratory scale using the HB-Line Phase II flowsheet. These tests were performed to determine what effect elevated temperatures would have on the neptunium dioxide in comparison to neptunium dioxide tested at ambient temperature. The headspace gas compositions following storage at elevated temperatures associated with normal conditions of transport (NCT) have been measured. These test results show an increase in hydrogen generation rate at elevated temperature and significant removal of oxygen from the headspace gas. The elevated temperature gas generation tests described in this report involved heating small test vessels containing neptunium dioxide and measuring the headspace gas pressure and composition at the end of the test period. Four samples were used in these tests to evaluate the impact of process variables on the gas generation rate. Two samples were calcined to 600 degrees Celsius and two were calcined to 650 degrees Celsius. Each test vessel contained approximately 9.5 g of neptunium dioxide. Following exposure to 75 per cent relative humidity (RH) for five days, these samples were loaded in air and then heated to between 105 and 115 degrees Celsius for about one month. At the conclusion of the test period, the headspace gas of each container was analyzed using a micro-gas chromatograph installed in the glovebox where the experiments were conducted. The pressure, volume, and composition data for the headspace gas samples were used to calculate average H2 generation rates.
Date: January 30, 2004
Creator: Duffey, JM
Partner: UNT Libraries Government Documents Department
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Pitting Corrosion in the Vapor Space and Liquid/Air Interface of High Level Radioactive Waste Tanks

Description: Corrosion in the vapor space and at the liquid/air interface of the Department of Energy (DOE) high level waste (HLW) tanks have emerged as potentially active corrosion mechanisms. Controls on the solution chemistry are in place to preclude the initiation and propagation of further nitrate induced pitting and stress corrosion cracking. However, recent experience has shown that steel not in contact with the bulk waste solution but exposed to the ''vapor space'' above the bulk waste and the liquid/air interface may be vulnerable to pitting or stress corrosion cracking. Experimentation was performed to determine the influence of steel surface characteristics and solution chemistry on pitting rates within the vapor space and at the liquid/air interface on ASTM A537 steels, the materials of construction of the tanks. The results suggest that inhibited bulk solution chemistry does not ensure pitting protection within the vapor space when there are surface inhomogeneities. However, the characteristic residual salts on the steel play a key role in the pitting characteristics.
Date: January 30, 2004
Creator: Subramanian, K.H.
Partner: UNT Libraries Government Documents Department
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TDNA Monthly Office Manager's Report: June 2004

Description: Monthly report written by the Texas Daily Newspaper Association's (TDNA's) office manager, Darla Thompson, to Phil Berkebile providing a summary of revenues and account balances, programs, meetings, and other activities in the office during the previous month.
Date: June 30, 2004
Creator: Thompson, Darla
Partner: UNT Libraries Special Collections
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TDNA Monthly Office Manager's Report: January 2004

Description: Monthly report written by the Texas Daily Newspaper Association's (TDNA's) office manager, Darla Thompson, to Phil Berkebile providing a summary of revenues and account balances, programs, meetings, and other activities in the office during the previous month.
Date: January 30, 2004
Creator: Thompson, Darla
Partner: UNT Libraries Special Collections
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TDNA Monthly Office Manager's Report: November/December 2004

Description: Monthly report written by the Texas Daily Newspaper Association's (TDNA's) office manager, Darla Thompson, to Phil Berkebile providing a summary of revenues and account balances, programs, meetings, and other activities in the office during the previous months. The header states that no officer report has been done for November/December as TDNA moved offices.
Date: November 30, 2004
Creator: Thompson, Darla
Partner: UNT Libraries Special Collections
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TDNA Monthly Office Manager's Report: April 2004

Description: Monthly report written by the Texas Daily Newspaper Association's (TDNA's) office manager, Darla Thompson, to Phil Berkebile providing a summary of revenues and account balances, programs, meetings, and other activities in the office during the previous month.
Date: April 30, 2004
Creator: Thompson, Darla
Partner: UNT Libraries Special Collections
open access

DropTests of 325 Pound 6M Packages

Description: There are many factors which affect the performance of a drum closure during drop tests. Important test conditions are: weight of package, height of drop, and angle of impact. Structural characteristics of the package determine its ability to withstand the test conditions imposed. These characteristics include: package diameter, shell material and thickness, strength of internal fill material (e.g., fiberboard), and configuration of closure (clamp-ring, bolted flange, etc.). For the clamp-ring closure configuration a study of published drop test results has shown that packages having a weight ratio of less than 50 per cent were typically able to retain their lids in hypothetical accident condition, 30-ft drop tests. Those having weight ratios greater than 50 per cent typically failed. Prior testing over the integrity of the clamp-ring closure, consistently demonstrated that the clamp-ring is unable to retain the drum lid in thirty foot drop tests of packages containing the maximum allowed weight (640 lb), which confirms the previous studies. To determine if the clamp-ring closure is adequate for packages with lower weight contents, a series of tests were performed on packages weighing around 325 lb (i.e., a typical shipping weight for DOE packages) at a range of impact angles as detailed in this report. The test results consistently demonstrated that the standard clamp-ring closure is unable to retain the drum lid of standard 6M packages weighing 325 lb.
Date: January 30, 2004
Creator: Gelder, L. A.
Partner: UNT Libraries Government Documents Department
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Mechanism of stress relaxation in Ge nanocrystals embedded in SiO2

Description: Ion-beam-synthesized {sup 74}Ge nanocrystals embedded in an amorphous silica matrix exhibit large compressive stresses in the as-grown state. The compressive stress is determined quantitatively by evaluating the Raman line shift referenced to the line position of free-standing nanocrystals. Post-growth thermal treatments lead to stress reduction. The stress relief process is shown to be governed by the diffusive flux of matrix atoms away from the local nanocrystal growth region. A theoretical model that quantitatively describes this process is presented.
Date: August 30, 2004
Creator: Sharp, I. D.; Yi, D. O.; Xu, Q.; Liao, C. Y.; Beeman, J. W.; Liliental-Weber, Z. et al.
Partner: UNT Libraries Government Documents Department
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First principle thousand atom quantum dot calculations

Description: A charge patching method and an idealized surface passivation are used to calculate the single electronic states of IV-IV, III-V, II-VI semiconductor quantum dots up to a thousand atoms. This approach scales linearly and has a 1000 fold speed-up compared to direct first principle methods with a cost of eigen energy error of about 20 meV. The calculated quantum dot band gaps are parametrized for future references.
Date: March 30, 2004
Creator: Wang, Lin-Wang & Li, Jingbo
Partner: UNT Libraries Government Documents Department
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Testing of Liquid Lithium Limiters in CDX-U

Description: Part of the development of liquid metals as a first wall or divertor for reactor applications must involve the investigation of plasma-liquid metal interactions in a functioning tokamak. Most of the interest in liquid-metal walls has focused on lithium. Experiments with lithium limiters have now been conducted in the Current Drive Experiment-Upgrade (CDX-U) device at the Princeton Plasma Physics Laboratory. Initial experiments used a liquid-lithium rail limiter (L3) built by the University of California at San Diego. Spectroscopic measurements showed some reduction of impurities in CDX-U plasmas with the L3, compared to discharges with a boron carbide limiter. While no reduction in recycling was observed with the L3, which had a plasma-wet area of approximately 40 cm2, subsequent experiments with a larger area fully toroidal lithium limiter demonstrated significant reductions in both recycling and in impurity levels. Two series of experiments with the toroidal limiter have now be en performed. In each series, the area of exposed, clean lithium was increased, until in the latest experiments the liquid-lithium plasma-facing area was increased to 2000 cm2. Under these conditions, the reduction in recycling required a factor of eight increase in gas fueling in order to maintain the plasma density. The loop voltage required to sustain the plasma current was reduced from 2 V to 0.5 V. This paper summarizes the technical preparations for lithium experiments and the conditioning required to prepare the lithium surface for plasma operations. The mechanical response of the liquid metal to induced currents, especially through contact with the plasma, is discussed. The effect of the lithium-filled toroidal limiter on plasma performance is also briefly described.
Date: July 30, 2004
Creator: Majeski, R.; Kaita, R.; Boaz, M.; Efthimion, P.; Gray, T.; Jones, B. et al.
Partner: UNT Libraries Government Documents Department
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Self-Organized Megastructures in Sedimentary Basins

Description: The overall theme of the project is to develop a quantitative understanding of basin reaction/transport/mechanical (RTM) processes on a broad range of scales. Our approach starts with the development of novel formulations of the basic RTM process rate laws (e.g. rock deformation, texture dynamics, and fracturing). We then set forth algorithms for solving the resulting partial differential equations numerically. As many of the parameters in the subsurface are not well known, we embed the entire approach in a probabilistic framework through information theory. The result is a set of novel software and conceptual papers that have been the first quantitative theory of a number of fundamental phenomena that take into account the full RTM dynamics of these systems.
Date: June 30, 2004
Creator: Ortoleva, Peter J.
Partner: UNT Libraries Government Documents Department
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Environmental Biosciences Program Fourth Quarter Report

Description: In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to its ability to task-organize scientific expertise from multiple disciplines in addressing these complex problems Current research projects have focused EBP talent and resources on providing the scientific basis for risk-based standards, risk-based decision making and the accelerated clean-up of widespread environmental hazards. These hazards include trichloroethylene (TCE), polychlorinated biphenyls (PCBs), asbestos and low-dose ionizing radiation. A project is also being conducted in the use of geographical information system technology to analyze population health risks related to environmental hazards as a tool for risk-based decision-making.
Date: June 30, 2004
Creator: Mohr, Lawrence C.
Partner: UNT Libraries Government Documents Department
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Development and evaluation of fully automated demand response in large facilities

Description: This report describes the results of a research project to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve electric grid reliability, manage electricity costs, and ensure that customers receive signals that encourage load reduction during times when the electric grid is near its capacity. The two main drivers for widespread demand responsiveness are the prevention of future electricity crises and the reduction of electricity prices. Additional goals for price responsiveness include equity through cost of service pricing, and customer control of electricity usage and bills. The technology developed and evaluated in this report could be used to support numerous forms of DR programs and tariffs. For the purpose of this report, we have defined three levels of Demand Response automation. Manual Demand Response involves manually turning off lights or equipment; this can be a labor-intensive approach. Semi-Automated Response involves the use of building energy management control systems for load shedding, where a preprogrammed load shedding strategy is initiated by facilities staff. Fully-Automated Demand Response is initiated at a building or facility through receipt of an external communications signal--facility staff set up a pre-programmed load shedding strategy which is automatically initiated by the system without the need for human intervention. We have defined this approach to be Auto-DR. An important concept in Auto-DR is that a facility manager is able to ''opt out'' or ''override'' an individual DR event if it occurs at a time when the reduction in end-use services is not desirable. This project sought to improve the feasibility and nature of Auto-DR strategies in large facilities. The research focused on technology development, testing, characterization, and evaluation relating to Auto-DR. This evaluation also …
Date: March 30, 2004
Creator: Piette, Mary Ann; Sezgen, Osman; Watson, David S.; Motegi, Naoya; Shockman, Christine & ten Hope, Laurie
Partner: UNT Libraries Government Documents Department
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ADVANCED HOT SECTION MATERIALS AND COATINGS TEST RIG

Description: The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principal activity during this reporting period were the evaluation of syngas combustor concepts, the evaluation of test section concepts and the selection of the preferred rig configuration.
Date: April 30, 2004
Creator: Reome, Scott & Davies, Dan
Partner: UNT Libraries Government Documents Department
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Pathways, Networks, and Systems: Theory and Experiments

Description: The international conference provided a unique opportunity for theoreticians and experimenters to exchange ideas, strategies, problems, challenges, language and opportunities in both formal and informal settings. This dialog is an important step towards developing a deep and effective integration of theory and experiments in studies of systems biology in humans and model organisms.
Date: October 30, 2004
Creator: Nadeau, Joseph H. & Lambris, John D.
Partner: UNT Libraries Government Documents Department
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Signal Analysis for Radiation Event Identification

Description: The method of digitizing the scintillation output signals from a lithiated sol-gel based glass is described. The design considerations for using the lithiated scintillator for the detection of Special Nuclear Material (SNM) is presented.
Date: December 30, 2004
Creator: Wallace, Steven A.
Partner: UNT Libraries Government Documents Department
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