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U.S. Atomic Energy Commission's Environmental Research Programs Established in the 1950s (open access)

U.S. Atomic Energy Commission's Environmental Research Programs Established in the 1950s

In 1946 the United States (U.S.) Congress passed the Atomic Energy Act and with it created the Atomic Energy Commission. For the ensuing half-century the AEC and its successors have pursued biological and environmental research with an unwavering mandate to exploit the use of fissionable and radioactive material for medical purposes and, at the same time, to ensure the health of it's workers, the public, and the environment during energy technology development and use (AEC. 1961; DOE 1983; DOE, 1997). The following pages are testimony to the success of this undeviating vision (Figure 1). From the early days of the AEC, cooperation has also linked researchers from the national laboratories, the academic community, and the private sector. The AEC-sponsored research both at national laboratories and universities, and also supported graduate students to develop a cadre of health physicists, radiation biologists, and nuclear engineers. Coordinating these diverse performers has been crucial to the unique teaming that has made many of the successes possible. The success of the biological and environmental research program has often been shared with other federal agencies. The future will demand even stronger and more substantive intraagency, interagency, and international collaborations.
Date: September 22, 1999
Creator: Reichle, D.E.
Object Type: Article
System: The UNT Digital Library
Optimization of a CNG series hybrid concept vehicle (open access)

Optimization of a CNG series hybrid concept vehicle

Compressed Natural Gas (CNG) has favorable characteristics as a vehicular fuel, in terms of fuel economy as well as emissions. Using CNG as a fuel in a series hybrid vehicle has the potential of resulting in very high fuel economy (between 26 and 30 km/liter, 60 to 70 mpg) and very low emissions (substantially lower than Federal Tier II or CARB ULEV). This paper uses a vehicle evaluation code and an optimizer to find a set of vehicle parameters that result in optimum vehicle fuel economy. The vehicle evaluation code used in this analysis estimates vehicle power performance, including engine efficiency and power, generator efficiency, energy storage device efficiency and state-of-charge, and motor and transmission efficiencies. Eight vehicle parameters are selected as free variables for the optimization. The optimum vehicle must also meet two perfect requirements: accelerate to 97 km/h in less than 10 s, and climb an infinitely long hill with a 6% slope at 97 km/h with a 272 kg (600 lb.) payload. The optimizer used in this work was originally developed in the magnetic fusion energy program, and has been used to optimize complex systems, such as magnetic and inertial fusion devices, neutron sources, and mil guns. …
Date: September 22, 1995
Creator: Aceves, S. M.; Smith, J. R.; Perkins, L. J.; Haney, S. W. & Flowers, D. L.
Object Type: Article
System: The UNT Digital Library
The Effect of Ramp Rate on the C49 to C54 Titanium Disilicide Phase Transformation from Ti and Ti(Ta) (open access)

The Effect of Ramp Rate on the C49 to C54 Titanium Disilicide Phase Transformation from Ti and Ti(Ta)

The C49 to C54 TiSi{sub 2} transformation temperature is shown to be reduced by increasing the ramp rate during rapid thermal processing and this effect is more pronounced for thinner initial Ti and Ti(Ta) films. Experiments were performed on blanket wafers and on wafers that had patterned polycrystalline Si lines with Si{sub 3}N{sub 4} sidewall spacers. Changing the ramp rate caused no change in the transformation temperature for 60 nm blanket Ti films. For blanket Ti films of 25 or 40 nm, however, increasing the ramp rate from 7 to 180 C/s decreased the transformation temperature by 15 C. Studies of patterned lines indicate that sheet resistance of narrow lines is reduced by increased ramp rates for both Ti and Ti(Ta) films, especially as the linewidths decrease below 0.4 {micro}m. This improvement is particularly pronounced for the thinnest Ti(Ta) films, which exhibited almost no linewidth effect after being annealed with a ramp rate of 75 C/s.
Date: September 22, 1999
Creator: BAILEY, GLENN A.; HU, YAO ZHI; SMITH, PAUL M. & TAY, SING PIN
Object Type: Article
System: The UNT Digital Library
Update on cavern disposal of NORM-contaminated oil field wastes. (open access)

Update on cavern disposal of NORM-contaminated oil field wastes.

Some types of oil and gas production and processing wastes contain naturally occurring radioactive material (NORM). If NORM is present at concentrations above regulatory levels in oil field waste, the waste requires special disposal practices. The existing disposal options for wastes containing NORM are limited and costly. Argonne National Laboratory has previously evaluated the feasibility, legality, risk and economics of disposing of nonhazardous oil field wastes, other than NORM waste, in salt caverns. Cavern disposal of nonhazardous oil field waste, other than NORM waste, is occurring at four Texas facilities, in several Canadian facilities, and reportedly in Europe. This paper evaluates the legality, technical feasibility, economics, and human health risk of disposing of NORM-contaminated oil field wastes in salt caverns as well. Cavern disposal of NORM waste is technically feasible and poses a very low human health risk. From a legal perspective, a review of federal regulations and regulations from several states indicated that there are no outright prohibitions against NORM disposal in salt caverns or other Class II wells, except for Louisiana which prohibits disposal of radioactive wastes or other radioactive materials in salt domes. Currently, however, only Texas and New Mexico are working on disposal cavern regulations, and …
Date: September 22, 1998
Creator: Veil, J. A.
Object Type: Article
System: The UNT Digital Library
Chemical vapor deposition of refractory ternary nitrides for advanced diffusion barriers (open access)

Chemical vapor deposition of refractory ternary nitrides for advanced diffusion barriers

Refractory ternary nitride films for diffusion barriers in microelectronics have been grown using chemical vapor deposition. Thin films of titanium-silicon-nitride, tungsten-boron-nitride, and tungsten-silicon-nitride of various compositions have been deposited on 150 mm Si wafers. The microstructure of the films are either fully amorphous for the tungsten based films, or nauocrystalline TiN in an amorphous matrix for titanium-silicon-nitride. All films exhibit step coverages suitable for use in future microelectronics generations. Selected films have been tested as diffusion barriers between copper and silicon, and generally perform extremely weH. These fiIms are promising candidates for advanced diffusion barriers for microelectronics applications. The manufacturing of silicon wafers into integrated circuits uses many different process and materials. The manufacturing process is usually divided into two parts: the front end of line (FEOL) and the back end of line (BEOL). In the FEOL the individual transistors that are the heart of an integrated circuit are made on the silicon wafer. The responsibility of the BEOL is to wire all the transistors together to make a complete circuit. The transistors are fabricated in the silicon itself. The wiring is made out of metal, currently aluminum and tungsten, insulated by silicon dioxide, see Figure 1. Unfortunately, silicon will …
Date: September 22, 1998
Creator: Custer, Jonathan S.; Fleming, James G.; Roherty-Osmun, Elizabeth & Smith, Paul Martin
Object Type: Article
System: The UNT Digital Library
Wavefront control of high power laser beams for the National Ignition Facility (NIF) (open access)

Wavefront control of high power laser beams for the National Ignition Facility (NIF)

The use of lasers as the driver for inertial confinement fusion and weapons physics experiments is based on their ability to produce high-energy short pulses in a beam with low divergence. Indeed, the focus ability of high quality laser beams far exceeds alternate technologies and is a major factor in the rationale for building high power lasers for such applications. The National Ignition Facility (NIF) is a large, 192-beam, high-power laser facility under construction at the Lawrence Livermore National Laboratory for fusion and weapons physics experiments. Its uncorrected minimum focal spot size is limited by laser system aberrations. The NIF includes a Wavefront Control System to correct these aberrations to yield a focal spot small enough for its applications. Sources of aberrations to be corrected include prompt pump-induced distortions in the laser amplifiers, previous-shot thermal distortions, beam off-axis effects, and gravity, mounting, and coating-induced optic distortions. Aberrations from gas density variations and optic manufacturing figure errors are also partially corrected. This paper provides an overview of the NIF Wavefront Control System and describes the target spot size performance improvement it affords. It describes provisions made to accommodate the NIF's high fluence (laser beam and flashlamp), large wavefront correction range, wavefront …
Date: September 22, 1999
Creator: Bliss, E.; Feldman, M.; Grey, A.; Koch, J.; Lund, L.; Sacks, R. et al.
Object Type: Article
System: The UNT Digital Library
Joint UK/US Radar Program. Progress report, August 1, 1995--August 31, 1995 (open access)

Joint UK/US Radar Program. Progress report, August 1, 1995--August 31, 1995

Modify Hughes x-band radar for airborne implementation. Upgrade to polarimetry, high-power, and add SLAR mode. Deploy in UK/US field experiments as needed.
Date: September 22, 1995
Creator: Twogood, R. E.; Brase, J. M. & Kiefer, R. D.
Object Type: Report
System: The UNT Digital Library
Use of Performance Assessment in Support of Waste Isolation Pilot Plant (WIPP) Programmatic Activity Planning (open access)

Use of Performance Assessment in Support of Waste Isolation Pilot Plant (WIPP) Programmatic Activity Planning

The Waste Isolation Pilot Plant (WIPP) is being developed by the U.S. Department of Energy (DOE) for the geologic (deep underground) disposal of transuranic (TRU) waste. A Compliance Certification Application (CCA) of the WIPP for such disposal was submitted to the U.S. Environmental Protection Agency (EPA) in October 1996, and was approved by EPA in May 1998. In June 1998, two separate, but related, lawsuits were filed, one against DOE and one against EPA. On March 22, 1999, the court ruled in favor of DOE, and on March 26, 1999, DOE formally began disposal operations at the WIPP for non-mixed (non-hazardous) TRU waste. Before the WIPP can begin receiving mixed (hazardous) TRU waste, a permit from the State of New Mexico for hazardous waste disposal needs to be issued. It is anticipated that the State of New Mexico will issue a hazardous waste permit by November 1999. It is further anticipated that the EPA lawsuit will be resolved by July 1999. Congress (Public Law 102-579, Section 8(f)) requires the WIPP project to be recertified by the EPA at least as frequently as once every five years from the first receipt of TRU waste at the WIPP site. As part of …
Date: September 22, 1999
Creator: Basabilvazo, George; Jow, Hong-Nian; Larson, Kurt W. & Marietta, Melvin G.
Object Type: Article
System: The UNT Digital Library
Computational Modeling of Heterogeneous Reactive Materials at the Mesoscale (open access)

Computational Modeling of Heterogeneous Reactive Materials at the Mesoscale

The mesoscopic processes of consolidation, deformation and reaction of shocked porous energetic materials are studied using shock physics analysis of impact on a collection of discrete ''crystals.'' Highly resolved three-dimensional CTH simulations indicate that rapid deformation occurs at material contact points causing large amplitude fluctuations of stress states with wavelengths of the order of several particle diameters. Localization of energy produces ''hot-spots'' due to shock focusing and plastic work near internal boundaries as material flows into interstitial regions. Numerical experiments indicate that ''hot-spots'' are strongly influenced by multiple crystal interactions. Chemical reaction processes also produce multiple wave structures associated with particle distribution effects. This study provides new insights into the micromechanical behavior of heterogeneous energetic materials strongly suggesting that initiation and sustained reaction of shocked heterogeneous materials involves states distinctly different from single jump state descriptions.
Date: September 22, 1999
Creator: BAER, MARVIN R.
Object Type: Article
System: The UNT Digital Library
A Review of Previous Research in Direct Energy Conversion Fission Reactors (open access)

A Review of Previous Research in Direct Energy Conversion Fission Reactors

From the earliest days of power reactor development, direct energy conversion was an obvious choice to produce high efficiency electric power generation. Directly capturing the energy of the fission fragments produced during nuclear fission avoids the intermediate conversion to thermal energy and the efficiency limitations of classical thermodynamics. Efficiencies of more than 80% are possible, independent of operational temperature. Direct energy conversion fission reactors would possess a number of unique characteristics that would make them very attractive for commercial power generation. These reactors would be modular in design with integral power conversion and operate at low pressures and temperatures. They would operate at high efficiency and produce power well suited for long distance transmission. They would feature large safety margins and passively safe design. Ideally suited to production by advanced manufacturing techniques, direct energy conversion fission reactors could be produced more economically than conventional reactor designs. The history of direct energy conversion can be considered as dating back to 1913 when Moseleyl demonstrated that charged particle emission could be used to buildup a voltage. Soon after the successful operation of a nuclear reactor, E.P. Wigner suggested the use of fission fragments for direct energy conversion. Over a decade after Wigner's …
Date: September 22, 1999
Creator: Duong, Henry; Polansky, Gary F.; Sanders, Thomas L. & Siegel, Malcolm D.
Object Type: Article
System: The UNT Digital Library
Actively Biased p-Channel MOSFET Studied with Scanning Capacitance Microscopy (open access)

Actively Biased p-Channel MOSFET Studied with Scanning Capacitance Microscopy

Scanning capacitance microscopy (SCM) was used to study the cross section of an operating p-channel MOSFET. We discuss the novel test structure design and the modifications to the SCM hardware that enabled us to perform SCM while applying dc bias voltages to operate the device. The results are compared with device simulations performed with DAVINCI.
Date: September 22, 1999
Creator: Nakakura, Craig Y.; Hetherington, Dale L.; Shaneyfelt, Marty R.; Dodd, Paul E. & De Wolf, P.
Object Type: Article
System: The UNT Digital Library
Testing astrophysical radiation hydrodynamics codes with hypervelocity jet experiments on the nova laser (open access)

Testing astrophysical radiation hydrodynamics codes with hypervelocity jet experiments on the nova laser

Recent shock tube experiments using the Nova laser facility have demonstrated that strong shocks and highly supersonic flows similar to those encountered in astrophysical jets can be studied in detail through carefully controlled experiment. We propose the use of high power lasers such as Nova, Omega, and NIF to perform experiments on radiation hydrodynamic problems such as jets involving the multidimensional dynamics of strong shocks. High power lasers are the only experimental facilities that can reach the very high Mach number regime. The experiments will serve both as diagnostics of astrophysically interesting gas dynamic problems, and could also form the basis of test problems for numerical algorithms for astrophysical radiation hydrodynamic codes, The potential for experimentally achieving a strongly radiative jet seems very good.
Date: September 22, 1999
Creator: Estabrook, K.; Farley, D.; Glendinning, S. G.; Remington, B. A.; Stone, J. & Turner, N.
Object Type: Article
System: The UNT Digital Library
Oscillation period of the interlayer coupling in epitaxial Fe/{sub 1-x}V{sub x}(100) and (211) superlattices. (open access)

Oscillation period of the interlayer coupling in epitaxial Fe/{sub 1-x}V{sub x}(100) and (211) superlattices.

The microscopic origin of the 18-{angstrom} period in the oscillatory interlayer exchange coupling of Fe/Cr( 100) and (211) superlattices is investigated by alloying the Cr spacer with V to alter its Fermi surface. The addition of V increases or decreases in size the various Fermi surface calipers that are candidates for governing the oscillation period, such as those that span the ellipse, lens, octahedron, and nested sheets. Epitaxial sputtered superlattices of (100) and (211) orientation were grown and characterized via magnetoresistance measurements as a function of spacer layer thickness for different V-doping levels. A small decrease of the oscillation period is found experimentally which strongly implicates the N-centered ellipse as the origin of the 18-{angstrom} period in Fe/Cr superlattices.
Date: September 22, 1998
Creator: You, C.-Y.
Object Type: Article
System: The UNT Digital Library
Dynamic equation of state and strength properties of unreacted PBXW-128 explosive (open access)

Dynamic equation of state and strength properties of unreacted PBXW-128 explosive

Shock equation of state and strength data have been obtained on the explosive PBXW-128 over the pressure range O-3 GPa using gun impact techniques and velocity interferometry diagnostics. Nonlinear shock-velocity-versus-particle velocity behavior is observed. Possible mechanisms are discussed and a Hug.oniot equation of slate model for the data is provided.
Date: September 22, 1998
Creator: Chhabildas, L. C.; Grady, D. E.; Reinhart, W. D. & Wilson, L. T.
Object Type: Article
System: The UNT Digital Library
A Low-Voltage Rotary Actuator Fabricated Using a Five-Level Polysilicon Surface Micromachining Technology (open access)

A Low-Voltage Rotary Actuator Fabricated Using a Five-Level Polysilicon Surface Micromachining Technology

The design, fabrication and characterization of a low-voltage rotary stepper motor are presented in this work. Using a five-level polysilicon MEMS technology, steps were taken to increase the capacitance over previous stepper motor designs to generate high torque at low voltages. A low-friction hub was developed to minimize frictional loads due to rubbing surfaces, producing an estimated resistive torque of about 6 pN-m. This design also allowed investigations into the potential benefit of using hard materials such as silicon nitride for lining of both the stationary and rotating hub components. The result is an electrostatic stepper motor capable of operation at less than six volts.
Date: September 22, 1999
Creator: Jakubczak, Jerome F., II; Krygowski, Thomas W.; Miller, Samuel L.; Rodgers, M. Steven & Sniegowski, Jeffry J.
Object Type: Article
System: The UNT Digital Library
K-Basins S/RIDS (open access)

K-Basins S/RIDS

The Standards/Requirements Identification Document(S/RID) is a list of the Environmental, Safety, and Health (ES&H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility
Date: September 22, 1995
Creator: Watson, D. J.
Object Type: Report
System: The UNT Digital Library
TPX: Contractor preliminary design review. Volume 1, Presentation and design description. Final report (open access)

TPX: Contractor preliminary design review. Volume 1, Presentation and design description. Final report

This first volume of the five volume set begins with a CPDR overview and then details the PF magnet system, manufacturing R&D, Westinghouse R&D, the central solenoid, the PF 5 ring coil, the PF 6/7 ring coil, quality assurance, and the system design description.
Date: September 22, 1995
Creator: Hartman, D.; Naumovich, G.; Walstrom, P.; Clarkson, I.; Schultheiss, J. & Burger, A.
Object Type: Report
System: The UNT Digital Library
Induction heating of a spherical aluminum moderator vessel for the Advanced Neutron Source (ANS) (open access)

Induction heating of a spherical aluminum moderator vessel for the Advanced Neutron Source (ANS)

This task was to identify and design a heating system to apply 15 kW of heat to a cold source vessel to simulate the Advanced Neutron Source reactor. This research project aims at the analysis of the induction heating of a spherical aluminum moderator vessel. Computer modeling is presented for the design and analysis of the induction heating system. The objective is to apply 15 kW of heat as uniformly as possible to the outer wall of a 410 mm diameter sphere of thickness 1.5 mm. The report also aims at the analysis of a system model which is simulated using the Eddycuff electromagnetic software. The computer model is built with the finite element analysis software Patran. The induction heating system analysis shows that the predicted performance is in close agreement with the computer simulated data. Hardware constraints such as power supplies and matching load are also analyzed in terms of performance and cost. Physical modeling is also suggested, in which the coil and the workpiece are scaled down.
Date: September 22, 1994
Creator: Yousuf, A.
Object Type: Report
System: The UNT Digital Library
Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 15, System design description. Volume 1 (open access)

Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 15, System design description. Volume 1

This System Design Description, prepared in accordance with the TPX Project Management Plan provides a summary or TF Magnet System design features at the conclusion of Phase I, Preliminary Design and Manufacturing Research. The document includes the analytical and experimental bases for the design, and plans for implementation in final design, manufacturing, test, and magnet integration into the tokamak. Requirements for operation and maintenance are outlined, and references to sources of additional information are provided.
Date: September 22, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Vapor and gas sampling of single-shell tank 241-SX-103 using the vapor sampling system (open access)

Vapor and gas sampling of single-shell tank 241-SX-103 using the vapor sampling system

This document presents sampling data resulting from the March 23, 1995, sampling of SST 241-SX-103 using the vapor sampling system.
Date: September 22, 1995
Creator: Caprio, G. S.
Object Type: Report
System: The UNT Digital Library
Quality Assurance Program Plan for Project W-379: Spent Nuclear Fuels Canister Storage Building Projec (open access)

Quality Assurance Program Plan for Project W-379: Spent Nuclear Fuels Canister Storage Building Projec

This document describes the Quality Assurance Program Plan (QAPP) for the Spent Nuclear Fuels (SNF) Canister Storage Building (CSB) Project. The purpose of this QAPP is to control project activities ensuring achievement of the project mission in a safe, consistent and reliable manner.
Date: September 22, 1995
Creator: Duncan, D.W.
Object Type: Report
System: The UNT Digital Library
Radiological consequences of a postulated drop of a maximally Lloaded FFTF fuel cask (open access)

Radiological consequences of a postulated drop of a maximally Lloaded FFTF fuel cask

Onsite and site boundary radiological consequences were estimated for a postulated accidental drop of an Interim Storage Cask (ISC) loaded 7 assemblies at the maximum available burnup. The postulated cask drop was assumed to occur from the maximum physically attainable height during crane movement of the cask. The resulting onsite and site boundary doses of 45 mSv and 0.04 mSv are far below the corresponding 1 Sv and 250 mSv risk guidelines for highly unlikely accidents
Date: September 22, 1995
Creator: Scott, P.A.
Object Type: Report
System: The UNT Digital Library
Radiological consequences of a hypothetical disruption of a maximally loaded FFTF fuel cask (open access)

Radiological consequences of a hypothetical disruption of a maximally loaded FFTF fuel cask

Radiological consequences at the site boundary were estimated for non-mechanistic disruption of an Interim Storage Cask (ISC) loaded with 7 assemblies at the maximum available burnup. The hypothetical disruption consisted of a crushing/shearing of the Core Component Container (CCC) along with all 7 assemblies and the creation of a large escape path out of the cask. The resulting site boundary dose of 1.6 mSv is far below the 250 mSv risk guidelines for highly unlikely events.
Date: September 22, 1995
Creator: Scott, P.A.
Object Type: Report
System: The UNT Digital Library
Alternatives for high-level waste forms, containers, and container processing systems (open access)

Alternatives for high-level waste forms, containers, and container processing systems

This study evaluates alternatives for high-level waste forms, containers, container processing systems, and onsite interim storage. Glass waste forms considered are cullet, marbles, gems, and monolithic glass. Small and large containers configured with several combinations of overpack confinement and shield casks are evaluated for these waste forms. Onsite interim storage concepts including canister storage building, bore holes, and storage pad were configured with various glass forms and canister alternatives. All favorable options include the monolithic glass production process as the waste form. Of the favorable options the unshielded 4- and 7-canister overpack options have the greatest technical assurance associated with their design concepts due to their process packaging and storage methods. These canisters are 0.68 m and 0.54 m in diameter respectively and 4.57 m tall. Life-cycle costs are not a discriminating factor in most cases, varying typically less than 15 percent.
Date: September 22, 1995
Creator: Crawford, T.W.
Object Type: Report
System: The UNT Digital Library