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Advanced Experimental Analysis of Controls on Microbial Fe(III) Oxide Reduction - Final Report - 09/16/1996 - 03/16/2001 (open access)

Advanced Experimental Analysis of Controls on Microbial Fe(III) Oxide Reduction - Final Report - 09/16/1996 - 03/16/2001

Considering the broad influence that microbial Fe(III) oxide reduction can have on subsurface metal/organic contaminant biogeochemistry, understanding the mechanisms that control this process is critical for predicting the behavior and fate of these contaminants in anaerobic subsurface environments. Knowledge of the factors that influence the rates of growth and activity of Fe(III) oxide-reducing bacteria is critical for predicting (i.e., modeling) the long-term influence of these organisms on the fate of contaminants in the subsurface, and for effectively utilizing Fe(III) oxide reduction and associated geochemical affects for the purpose of subsurface metal/organic contamination bioremediation. This research project will refine existing models for microbiological and geochemical controls on Fe(III) oxide reduction, using laboratory reactor systems that mimic, to varying degrees, the physical and chemical conditions of the subsurface. Novel experimental methods for studying the kinetics of microbial Fe(III) oxide reduction and measuring growth rates of Fe(III) oxide-reducing bacteria will be developed. These new methodologies will be directly applicable to studies on subsurface contaminant transformations directly coupled to or influenced by microbial Fe(III) oxide reduction.
Date: March 16, 2001
Creator: Roden, Eric E.
System: The UNT Digital Library
Advanced Worker Protection System: Final Report (open access)

Advanced Worker Protection System: Final Report

From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To …
Date: March 16, 2001
Creator: Hedgehock, Judson
System: The UNT Digital Library
Agriculture in Afghanistan and Neighboring Asian Countries (open access)

Agriculture in Afghanistan and Neighboring Asian Countries

Agriculture (as measured by share of gross domestic product and employment) is a significant economic sector in seven Central and South Asian countries: Afghanistan, Iran, Kyrgyzstan, Pakistan, Tajikistan, Turkmenistan, and Uzbekistan. All of these countries are net food importers. Some have experienced successive years of drought, which has contributed to noticeable declines in agricultural output and the need to increase commodity imports. The United Nations’ World Food Program reports that both Afghanistan and Tajikistan are currently in need of emergency food assistance to cover sizable food deficits. The food outlook in Afghanistan is made uncertain by ongoing military conflict.
Date: November 16, 2001
Creator: Jurenas, Remy
System: The UNT Digital Library
Air Quality and Emissions Trading: A Primer (open access)

Air Quality and Emissions Trading: A Primer

This report briefly discusses the extent to which emissions trading has been used in the United States, explains how trading programs work, analyzes factors that can influence the effectiveness of trading, and examines some of the principal arguments related to the use of trading to control air pollution.
Date: April 16, 2001
Creator: Bearden, David M.
System: The UNT Digital Library
The Alpha Dynamo Effects in Laboratory Plasmas (open access)

The Alpha Dynamo Effects in Laboratory Plasmas

A concise review of observations of the alpha dynamo effect in laboratory plasmas is given. Unlike many astrophysical systems, the laboratory pinch plasmas are driven magnetically. When the system is overdriven, the resultant instabilities cause magnetic and flow fields to fluctuate, and their correlation induces electromotive forces along the mean magnetic field. This alpha-effect drives mean parallel electric current, which, in turn, modifies the initial background mean magnetic structure towards the stable regime. This drive-and-relax cycle, or the so-called self-organization process, happens in magnetized plasmas in a timescale much shorter than resistive diffusion time, thus it is a fast and unquenched dynamo process. The observed alpha-effect redistributes magnetic helicity (a measure of twistedness and knottedness of magnetic field lines) but conserves its total value. It can be shown that fast and unquenched dynamos are natural consequences of a driven system where fluctuations are statistically either not stationary in time or not homogeneous in space, or both. Implications to astrophysical phenomena will be discussed.
Date: October 16, 2001
Creator: Ji, Hantao & Prager, Stewart C.
System: The UNT Digital Library
Animal Agriculture: Current Issues (open access)

Animal Agriculture: Current Issues

A variety of animal agriculture issues, including low livestock prices, the impact of consolidation in the meat packing industry, trade, and the environmental impacts of large feedlots, generated interest in the 106th and 107th Congresses. This report addresses this issues in detail.
Date: April 16, 2001
Creator: Heykoop, Jerry & Segarra, Alejandro E.
System: The UNT Digital Library
Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Quarterly Progress Report: January 1--March 31, 2001 (open access)

Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Quarterly Progress Report: January 1--March 31, 2001

The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents.
Date: June 16, 2001
Creator: Hickman, T. Scott & Justice, James J.
System: The UNT Digital Library
Arsenic in Drinking Water: Recent Regulatory Developments and Issues (open access)

Arsenic in Drinking Water: Recent Regulatory Developments and Issues

This report discusses issues regarding the arsenic’s health effects and how to reduce the uncertainty in assessing health risks associated with exposure to low levels of arsenic. Environmental Protection Agency (EPA) issued the current standard of 50 parts per billion (ppb) in 1975. . This report reviews EPA efforts to develop a new arsenic rule and summarizes key provisions and subsequent events.
Date: November 16, 2001
Creator: Tiemann, Mary
System: The UNT Digital Library
Burial Ground Uptake Studies - Surface Contamination (open access)

Burial Ground Uptake Studies - Surface Contamination

This study reports the findings from surficial, aerially deposited materials present at a particular distance from H- and F-Area stacks. A mathematical computer model, DOSTOMAN, has been developed to evaluate the long-term potential hazard associated with burying low-level beta-gamma TRU wastes. The model predicts the dose to man due to radionuclide transfer through environmental pathways after plans operations and waste surveillance cease.
Date: August 16, 2001
Creator: Gay, D.D.
System: The UNT Digital Library
Campaign Finance Bills in the 107th Congress: Comparison of H.R. 380 (Shays-Meehan) with S. 27 (McCain-Feingold) (open access)

Campaign Finance Bills in the 107th Congress: Comparison of H.R. 380 (Shays-Meehan) with S. 27 (McCain-Feingold)

As in the last two Congresses, campaign finance reform will be a major issue in the 107th Congress, with attention again centered on the Senate McCain-Feingold and House Shays-Meehan bills. S. 27 (Bipartisan Campaign Reform Act of 2001), introduced on January 22, 2001, will be considered by the Senate in March 2001; H.R. 380 (Bipartisan Campaign Finance Reform Act of 2001) was introduced January 31. Both bills ban the raising of soft money by national parties and the spending of it by state and local parties on federal election-related activities (as defined). But on the other key provision–issue advocacy–they differ notably. H.R. 380 offers a broad new definition of express advocacy, subjecting activity meeting that standard to all aspects of federal election law regulation. S. 27 classifies some messages as electioneering communications, requiring their disclosure and banning their funding by unions or for-profit corporations. This report summarizes and compares these two measures, according to various categories.
Date: February 16, 2001
Creator: Cantor, Joseph E.
System: The UNT Digital Library
Campaign Finance: Constitutional and Legal Issues of Soft Money (open access)

Campaign Finance: Constitutional and Legal Issues of Soft Money

This report provides an overview on constitutional and legal issues of soft money.
Date: July 16, 2001
Creator: Whitaker, L. Paige
System: The UNT Digital Library
Campaign Finance in the 2000 Federal Elections: Overview and Estimates of the Flow of Money (open access)

Campaign Finance in the 2000 Federal Elections: Overview and Estimates of the Flow of Money

Federal election law regulates money in federal elections through a ban on union and corporate treasury money, limits on contributions, and uniform, periodic disclosure of receipts and expenditures. Money raised and spent under these laws to directly influence federal elections is commonly known as hard money. Money that is largely outside the restrictions and prohibitions of the federal regulatory framework–but raised and spent in a manner suggesting possible intent to affect federal elections–is commonly known as soft money.
Date: March 16, 2001
Creator: Cantor, Joseph E.
System: The UNT Digital Library
Canister Transfer System Event Sequence Calculation (open access)

Canister Transfer System Event Sequence Calculation

The ''Department of Energy Spent Nuclear Fuel Canister, Transportation, and Monitored Geologic Repository Systems, Structures, and Components Performance Allocation Study'' (CRWMS M&O 2000b) allocated performance to both the canisters received at the Monitored Geologic Repository (MGR) and the MGR Canister Transfer System (CTS). The purpose of this calculation is to evaluate an assumed range of canister and CTS performance allocation failure probabilities and determine the effect of these failure probabilities on the frequency of a radionuclide release. Five canister types are addressed in this calculation; high-level radioactive waste (HLW) canisters containing vitrified borosilicate glass, HLW canisters containing immobilized plutonium surrounded by borosilicate glass (Pu/HLW canisters), Department of Energy (DOE) spent nuclear fuel (DSNF) standard canisters (4 sizes), DSNF multi-canister overpacks (MCOs) for N-reactor fuel and other selected DSNF, and naval spent nuclear fuel (SNF) canisters (2 sizes). The quality assurance program applies to this calculation, and the work is performed in accordance with procedure AP-3.12Q, ''Calculations''. The work done for this calculation was evaluated according to AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities'' that determined this activity to be subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (DOE 2000a). This work was …
Date: August 16, 2001
Creator: Morissette, Richard
System: The UNT Digital Library
Carbon Dioxide for pH Control (open access)

Carbon Dioxide for pH Control

Cardox, the major supplier of carbon dioxide, has developed a diffuser to introduce carbon dioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.
Date: August 16, 2001
Creator: Wagonner, R.C.
System: The UNT Digital Library
Centrifugally confined plasmas for magnetic fusion energy. Final technical report for period March 15, 1998 - September 1, 2000 (open access)

Centrifugally confined plasmas for magnetic fusion energy. Final technical report for period March 15, 1998 - September 1, 2000

The purpose of the research funded under this study grant was to investigate the feasibility of a small scale experiment to test the concept of centrifugal confinement as a magnetic fusion energy scheme and to develop conceptual designs for important components of such an experiment. This work falls in the category of Innovative Confinement Concepts, as defined by the Office of Fusion Energy. The results of the funded work were very successful in that various studies were conducted which showed the concept to be viable and these studies led to design improvements. In addition, the major components of an experiment were identified and designed at least to the conceptual stage. In September, 2000 the Maryland Centrifugal Torus was funded for construction, in no small part because of the progress made during the time period reported here. The centrifugal confinement concept for fusion is based on three principles: (1) centrifugal forces from supersonic plasma rotation perpendicular to a strong magnetic field can provide effective confinement along the field; (2) the concomitant large velocity shear will suppress even macro-MHD instabilities; and (3) the sheared rotation will heat the plasma via viscous dissipation. Technical progress was made in clarifying and quantifying these concepts …
Date: July 16, 2001
Creator: Ellis, Richard F.
System: The UNT Digital Library
China's Proliferation of Weapons of Mass Destruction and Missiles: Current Policy Issues (open access)

China's Proliferation of Weapons of Mass Destruction and Missiles: Current Policy Issues

This report provides a brief background analysis and recent developments regarding China’s Proliferation of Weapons of Mass Destruction and Missiles. The report includes topics such as: Recent Proliferation Transfers, chemical, nuclear, and missile technology sales to Iran, Pakistan, Libya, Syria, trade controls, nonproliferation and arms control.
Date: May 16, 2001
Creator: Kan, Shirley A.
System: The UNT Digital Library
Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers (open access)

Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers

Chromaticity measurements are usually done by changing the energy of the beam by a known amount and measuring the change in betatron tune with a spectrum analyzer. The energy change is done by adjusting the RF frequency. The change in RF frequency is made large enough so that the change in betatron tune can be seen. If synchrotron motion is present in the beam, then measuring the change in betatron tune can be difficult. This note will outline a method to measure the change in betatron tune by phase-modulating the RF and measuring the phase modulated betatron spectrum Extremely small resolution bandwidths are available on modern vector signal analyzers. A small resolution bandwidth is equivalent to measuring the chromaticity many times and averaging the results. This would permit much smaller shifts in betatron tunes to be measured. The phase-modulated signal consists of sidebands whose amplitudes are given by Bessel functions. The complication of the Bessel functions can be removed if the vector signal analyzer is capable of phase demodulation. The sign of the chromaticity can be determined by observing the modulation spectrum at both betatron sidebands.
Date: February 16, 2001
Creator: McGinnis, Dave
System: The UNT Digital Library
Chronic Dermal Toxicity of Epoxy Resins I. Skin Carcinogenic Potency and General Toxicity (open access)

Chronic Dermal Toxicity of Epoxy Resins I. Skin Carcinogenic Potency and General Toxicity

Epoxy resins are a diverse class of chemicals that differ in structure, physical properties, and, presumably, biological activity. The purpose of these experiments was to compare the chronic dermal toxicity and carcinogenicity of selected commercial epoxy resins and to determine the potential for positive synergistic carcinogenic interactions between different resins. This work is an extension and continuation of a Department of Energy sponsored program to evaluate epoxy resins for potential occupational health risks. The materials examined were chosen on the basis of their interest to the U.S. government. They are representative of the manufacturer's production at the time, and therefore the data are completely valid only for the specific production period. Results of the experimental exposures will be reported in two parts. This report describes the test materials, their chemical and physical characteristics and the experimental design. General (systemic) toxicity will be evaluated and the skin carcinogenicity of the materials compared. A subsequent report will provide morphological descriptions of skin and significant internal pathology induced by the various treatments.
Date: January 16, 2001
Creator: Holland, J. M.
System: The UNT Digital Library
The Cleaning of Aluminum Frame Assembly Units (open access)

The Cleaning of Aluminum Frame Assembly Units

The Brulin immersion and the precision cleaning experiments have shown that neither the Brulin solution nor the precision cleaning in AstroPak causes the smut formation on aluminum surfaces. The acid-bath cleaning in GTC is the primary source of the smut formation. The current GTC acid formulation etches the aluminum matrix quite aggressively, but does not appear to appreciably attack the Si particles. Therefore, this acid-bath cleaning will leave the cast-aluminum part surfaces with many protruded Si particles, which could potentially cause smut problems in the cleaning process down-stream. To ensure the removal of all loose Si particles from the cast-aluminum parts, it is necessary to physically hand-wipe and vigorously wash the acid-bath cleaned surfaces. Furthermore, the casting porosity in alloy A356 could be another source in causing high swipe readings in the FAU parts.
Date: May 16, 2001
Creator: Shen, T H
System: The UNT Digital Library
Closed Loop Feedback of MHD Instabilities on DIII-D (open access)

Closed Loop Feedback of MHD Instabilities on DIII-D

A system of coils, sensors and amplifiers has been installed on the DIII-D tokamak to study the physics of feedback stabilization of low-frequency MHD [magnetohydrodynamic] modes such as the Resistive Wall Mode (RWM). Experiments are being performed to assess the effectiveness of this minimal system and benchmark the predictions of theoretical models and codes. In the last campaign, the experiments have been extended to a regime where the RWM threshold is lowered by a fast ramp of the plasma current. In these experiments, the onset time of the RWM is very reproducible. With this system, the onset of the RWM has been delayed by up to 100 msec without degrading plasma performance. The growth rate of the mode increases proportional to the length of delay, suggesting that the plasma is evolving towards a more unstable configuration. The present results have suggested directions for improving the feedback system including better sensors and improved feedback algorithms.
Date: January 16, 2001
Creator: Fredrickson, E. D.; Bialek, J.; Garofalo, A. M.; Johnson, L. C.; La Haye, R. J. & Lazarus, E. A.
System: The UNT Digital Library
Contract Management: No DOD Proposal to Improve Contract Service Costs Reporting (open access)

Contract Management: No DOD Proposal to Improve Contract Service Costs Reporting

A letter report issued by the General Accounting Office with an abstract that begins "The Department of Defense (DOD) has not developed a proposal to improve the accuracy of the reporting of contract service costs. Without accurate and reliable information, Congress cannot effectively use the information reported for DOD in the President's budget as it drafts and passes laws that affect spending. Last year, DOD agreed to develop a proposal to resolve this problem. GAO was told recently that DOD's momentum to develop a written proposal had subsided."
Date: February 16, 2001
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Conventional Arms Transfers to Developing Nations, 1993-2000 (open access)

Conventional Arms Transfers to Developing Nations, 1993-2000

This report is prepared annually to provide unclassified quantitative data on conventional arms transfers to developing nations by the United States and foreign countries for the preceding eight calendar years. Some general data are provided on worldwide conventional arms transfers, but the principal focus is the level of arms transfers by major weapons suppliers to nations in the developing world. The data in the report illustrate how global patterns of conventional arms transfers have changed in the post-Cold War and post-Persian Gulf War years.
Date: August 16, 2001
Creator: Grimmett, Richard F.
System: The UNT Digital Library
Copyright Cases in the Courts: Napster, MP3 Digital Music, and DVD Motion Picture Encryption Technology (open access)

Copyright Cases in the Courts: Napster, MP3 Digital Music, and DVD Motion Picture Encryption Technology

This report discusses copyright cases in the courts, including Napster, MP3 digital music, and DVD motion picture.
Date: February 16, 2001
Creator: Jeweler, Robin
System: The UNT Digital Library
The Cost of Prescription Drugs for the Uninsured Elderly and Legislative Approaches (open access)

The Cost of Prescription Drugs for the Uninsured Elderly and Legislative Approaches

The purpose of this report is to explain why many of those who are least able to afford high drug costs are those who are most frequently charged the most. This report describes the basic economic theory underlying price differentiation and, in the context of the pharmaceutical market, analyzes the role and behavior of pharmacy benefit managers (PBMs), pharmaceutical manufacturers, and retail pharmacies, respectively. It also looks at a number of the criticisms that have been made of the practice of differential pricing. Finally, this report discusses various policy approaches aimed at assisting the elderly to purchase prescription drugs.
Date: January 16, 2001
Creator: Library of Congress. Congressional Research Service. Resources, Science, and Industry Division.
System: The UNT Digital Library