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Department of Defense: Military Assistance During the Branch Davidian Incident (open access)

Department of Defense: Military Assistance During the Branch Davidian Incident

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Defense's (DOD) response to the House Committee on Government Reform regarding whether it delivered high explosive ammunition to the Federal Bureau of Investigation (FBI) during the Branch Davidian Incident. The Committee also asked whether GAO would change any of the findings in its April 1999 report based on DOD's response."
Date: August 21, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
VA Health Care: Supply of Nursing Home Beds Is Sufficient to 2005 in the Detroit, Michigan, Area (open access)

VA Health Care: Supply of Nursing Home Beds Is Sufficient to 2005 in the Detroit, Michigan, Area

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Veterans Affairs' (VA) needs assessment of nursing home care in Detroit, Michigan."
Date: August 21, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Responses to Questions From May 18th Hearing on Uses of Social Security Numbers (open access)

Responses to Questions From May 18th Hearing on Uses of Social Security Numbers

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO responded to congressional questions regarding the May 18th hearing on the uses of social security numbers (SSN), focusing on the following questions: (1) what problems are caused when necessary SSNs are not included on tax forms submitted to the Internal Revenue Service (IRS); and (2) what actions federal agencies are taking in the area of using biometrics to identify individuals."
Date: August 21, 2000
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Effects of Burnable Absorbers on PWR Spent Nuclear Fuel (open access)

Effects of Burnable Absorbers on PWR Spent Nuclear Fuel

Burnup credit is an ongoing issue in designing and licensing transportation and storage casks for spent nuclear fuel (SNF). To address this issue, in July 1999, the U.S. Nuclear Regulatory Commission (NRC), Spent Fuel Project Office, issued Interim Staff Guidance-8 (ISG-8), Revision 1 allowing limited burnup credit for pressurized water reactor (PWR) spent nuclear fuel (SNF) to be used in transport and storage casks. However, one of the key limitations for a licensing basis analysis as stipulated in ISG-8, Revision 1 is that ''burnup credit is restricted to intact fuel assemblies that have not used burnable absorbers''. Because many PWR fuel designs have incorporated burnable-absorber rods for more than twenty years, this restriction places an unnecessary burden on the commercial nuclear power industry. This paper summarizes the effects of in-reactor irradiation on the isotopic inventory of PWR fuels containing different types of integral burnable absorbers (BAs). The work presented is illustrative and intended to represent typical magnitudes of the reactivity effects from depleting PWR fuel with different types of burnable absorbers.
Date: August 21, 2000
Creator: O'Leary, P.M. & Pitts, M. L.
Object Type: Report
System: The UNT Digital Library
Evolution of Surface Structure and Phase Separation in GaInAsSb (open access)

Evolution of Surface Structure and Phase Separation in GaInAsSb

Atomic force microscopy was used to study changes in the surface step structure of GaInAsSb layers with varying degrees of phase separation. The layers were grown by organometallic vapor phase epitaxy on (001) GaSb substrates with 2{sup o} miscut angles toward (-1-11)A, (1-11)B, and (101). Alloy decomposition was observed by contrast modulations in plan-view transmission electron microscopy, and broadening in x-ray diffraction and photoluminescence peaks. GaInAsSb layers with a minimal degree of phase separation exhibit a step-bunched step structure. A gradual degradation in the periodicity of the step structure is observed as the alloy decomposes into GaAs- and InSb-rich regions. The surface eventually develops trenches to accommodate the local strain associated with composition variations, which are on the order of a few percent. The surface composition is affected by substrate miscut angle, and although phase separation cannot be eliminated, its extent can be reduced by growing on substrates miscut toward (1-11)B.
Date: August 21, 2000
Creator: Vineis, C. J.; Wang, C. A. & Calawa, D. R.
Object Type: Report
System: The UNT Digital Library
Experience With the SCALE Criticality Safety Cross Section Libraries (open access)

Experience With the SCALE Criticality Safety Cross Section Libraries

This report provides detailed information on the SCALE criticality safety cross-section libraries. Areas covered include the origins of the libraries, the data on which they are based, how they were generated, past experience and validations, and performance comparisons with measured critical experiments and numerical benchmarks. The performance of the SCALE criticality safety cross-section libraries on various types of fissile systems are examined in detail. Most of the performance areas are demonstrated by examining the performance of the libraries vs critical experiments to show general trends and weaknesses. In areas where directly applicable critical experiments do not exist, performance is examined based on the general knowledge of the strengths and weaknesses of the cross sections. In this case, the experience in the use of the cross sections and comparisons with the results of other libraries on the same systems are relied on for establishing acceptability of application of a particular SCALE library to a particular fissile system. This report should aid in establishing when a SCALE cross-section library would be expected to perform acceptably and where there are known or suspected deficiencies that would cause the calculations to be less reliable. To determine the acceptability of a library for a particular …
Date: August 21, 2000
Creator: Bowman, S. M.
Object Type: Report
System: The UNT Digital Library
Impact of Drill and Blast Excavation on Repository Performance Confirmation (open access)

Impact of Drill and Blast Excavation on Repository Performance Confirmation

There has been considerable work accomplished internationally examining the effects of drill and blast excavation on rock masses surrounding emplacement openings of proposed nuclear waste repositories. However, there has been limited discussion tying the previous work to performance confirmation models such as those proposed for Yucca Mountain, Nevada. This paper addresses a possible approach to joining the available information on drill and blast excavation and performance confirmation. The method for coupling rock damage data from drill and blast models to performance assessment models for fracture flow requires a correlation representing the functional relationship between the peak particle velocity (PPV) vibration levels and the potential properties that govern water flow rates in the host rock. Fracture aperture and frequency are the rock properties which may be most influenced by drill and blast induced vibration. If it can be shown (using an appropriate blasting model simulation) that the effect of blasting is far removed from the waste package in an emplacement drift, then disturbance to the host rock induced in the process of drill and blast excavation may be reasonably ignored in performance assessment calculations. This paper proposes that the CANMET (Canada Center for Mineral and Energy Technology) Criterion, based on properties …
Date: August 21, 2000
Creator: Keller, R.; Francis, N.; Houseworth, J. & Kramer, N.
Object Type: Report
System: The UNT Digital Library
Radiation-Neutralization of Stored Biological Warfare Agents with Low-Yield Nuclear Warheads (open access)

Radiation-Neutralization of Stored Biological Warfare Agents with Low-Yield Nuclear Warheads

MCNP Monte Carlo radiation transport computations were performed exploring the capability of low-yield nuclear fusion and fission warheads to neutralize biological warfare agents with the radiation dose deposited in the agent by the prompt neutron output. The calculations were done for various typical storage configurations on the ground in the open air or in a warehouse building. This application of nuclear weapons is motivated by the observation that, for some military scenarios, the nuclear collateral effects area is much smaller than the area covered with unacceptable concentrations of biological agent dispersed by the use of conventional high explosive warheads. These calculations show that biological agents can be radiation-neutralized by low-yield nuclear warheads over areas that are sufficiently large to be useful for military strikes. This report provides the calculated doses within the stored agent for various ground ranges and heights-of-burst.
Date: August 21, 2000
Creator: Kruger, H.
Object Type: Report
System: The UNT Digital Library
Results on Plasma Focusing of High Energy Density Electron and Positron Beams (open access)

Results on Plasma Focusing of High Energy Density Electron and Positron Beams

The authors present results from the SLAC E-150 experiment on plasma focusing of high energy density electron and, for the first time, positron beams. They also discuss measurements on plasma lens-induced synchrotron radiation, longitudinal dynamics of plasma focusing, and laser- and beam-plasma interactions.
Date: August 21, 2000
Creator: Ng, J. S. T.; Chen, P.; Craddock, W.; Decker, F. J.; Field, R. C.; Hogan, M. et al.
Object Type: Article
System: The UNT Digital Library
Modeling and Demonstration of a Saturated Ni-Like Mo X-Ray Laser (open access)

Modeling and Demonstration of a Saturated Ni-Like Mo X-Ray Laser

The technique of using a nsec pulse to preform and ionize the plasma followed by a psec pulse to heat the plasma has enabled us to achieve saturated laser output for low-Z neon-like and nickel-like ions driven by small lasers with less than ten joules of energy. In this work we present and model recent experiments done using the COMET laser at Lawrence Livermore National Laboratory to illuminate slab targets of Mo up to 1 cm long with a one joule, 600 ps prepulse followed 700 psec later by a five joule, one psec drive pulse. The experiments demonstrate saturated output on the Ni-like Mo 3d{sup 9} 4d {sup 1}S{sub 0} {yields} 3d{sup 9} 4p {sup 1}P{sub 1} laser line at 18.9 nm. The small signal gain and gain length product are estimated by measuring the laser output versus target length. Experiments are done using multilayer mirrors to obtain two-dimensional images of the output aperture of the laser and to measure the total laser energy as a function of various parameters such as the delay between the short and long pulses and the energy of the two pulses. To model the experiments the LASNEX code is used to calculate the …
Date: August 21, 2000
Creator: Nilsen, J.
Object Type: Article
System: The UNT Digital Library
Award-Winning System Assays Radiation Waste With Radiation (open access)

Award-Winning System Assays Radiation Waste With Radiation

More than half a million drums of radioactive waste are stored at 30 Department of Energy sites across the nation, with thousands more to come as facilities at weapons complex sites are dismantled. All of these drums must be assayed to determine and verify their contents and levels of radioactivity so they can be transported for permanent storage or disposal. A system that assays containers of radioactive waste safely, accurately, and nonintrusively has garnered a prestigious R and D 100 Award--presented annually by R and D Magazine to ''the 100 most technologically significant new products and processes of the year''--for Lawrence Livermore National Laboratory and its commercial partner, Bio-Imaging Research, Inc. (BIR) from Lincolnshire, Illinois. The award-winning Waste Inspection Tomography for Non-Destructive Assay (WIT-NDA) system was developed by a team of engineers and physicists headed by Livermore's Patrick Roberson and Harry Martz. The system combines active and passive computed tomography and nuclear spectroscopy to accurately quantify all detectable gamma rays emitted from waste containers. The WIT-NDA is part of BIR's Waste Inspection Tomography system, which provides nondestructive examination and assay of radioactive waste and has been commercially available since August 1999. ''The WIT-NDA is an excellent example of successful technology …
Date: August 21, 2000
Creator: Roberson, G. P.
Object Type: Report
System: The UNT Digital Library
The Design of a Novel Survey for Small Objects in the Solar System (open access)

The Design of a Novel Survey for Small Objects in the Solar System

We evaluated several concepts for a new survey for small objects in the Solar System. We designed a highly novel survey for comets in the outer region of the Solar System, which exploits the occultations of relatively bright stars to infer the presence of otherwise extremely faint objects. The populations and distributions of these objects are not known; the uncertainties span orders of magnitude! These objects are important scientifically as probes of the primordial solar system, and programmatically now that major investments may be made in the possible mitigation of the hazard of asteroid or comet collisions with the Earth.
Date: August 21, 2000
Creator: Alcock, C.; Chen, W.P.; de Pater, I.; Lee, T.; Lissauer, J.; Rice, J. et al.
Object Type: Report
System: The UNT Digital Library
Benchmarks and models for 1-D radiation transport in stochastic participating media (open access)

Benchmarks and models for 1-D radiation transport in stochastic participating media

Benchmark calculations for radiation transport coupled to a material temperature equation in a 1-D slab and 1-D spherical geometry binary random media are presented. The mixing statistics are taken to be homogeneous Markov statistics in the 1-D slab but only approximately Markov statistics in the 1-D sphere. The material chunk sizes are described by Poisson distribution functions. The material opacities are first taken to be constant and then allowed to vary as a strong function of material temperature. Benchmark values and variances for time evolution of the ensemble average of material temperature energy density and radiation transmission are computed via a Monte Carlo type method. These benchmarks are used as a basis for comparison with three other approximate methods of solution. One of these approximate methods is simple atomic mix. The second approximate model is an adaptation of what is commonly called the Levermore-Pomraning model and which is referred to here as the standard model. It is shown that recasting the temperature coupling as a type of effective scattering can be useful in formulating the third approximate model, an adaptation of a model due to Su and Pomraning which attempts to account for the effects of scattering in a stochastic …
Date: August 21, 2000
Creator: Miller, D. S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Envelope Modes of Beams with Angular Momentum (open access)

Envelope Modes of Beams with Angular Momentum

For a particle beam propagating in an alternating gradient focusing system, envelope equations are often employed to describe the evolution of the beam radii in the two directions transverse to the direction of propagation, and aligned with the principle axes of the alternating gradient system. When the beams have zero net angular momentum and when the alternating gradient focusing is approximated by a continuous focusing system, there are two normal modes to the envelope equations: the 'breathing' mode and a 'quadrupole' mode. In the former, the two radii oscillate in phase, and in the latter the radii oscillate 180 degrees out of phase. In this paper, we extend the analysis to include beams that have a finite angular momentum. We perturb the moment equations of ref. [1], wherein it was assumed that space charge is a distributed in a uniform density ellipse. Two additional modes are obtained. The breathing mode remains, but the quadrupole mode is split into two modes, and a new low frequency mode appears. We calculate the frequencies and eigenmodes of these four modes as a function of tune depression and a dimensionless net angular momentum. These modes can be excited by rotational errors of the quadrupoles …
Date: August 21, 2000
Creator: Barnard, John J. & Losic, Bojan
Object Type: Article
System: The UNT Digital Library
Adaptive optics for improved retinal surgery and diagnostics (open access)

Adaptive optics for improved retinal surgery and diagnostics

It is now possible to field a compact adaptive optics (AO) system on a surgical microscope for use in retinal diagnostics and surgery. Recent developments in integrated circuit technology and optical photonics have led to the capability of building an AO system that is compact and significantly less expensive than traditional AO systems. It is foreseen that such an AO system can be integrated into a surgical microscope while maintaining a package size of a lunchbox. A prototype device can be developed in a manner that lends itself well to large-scale manufacturing.
Date: August 21, 2000
Creator: Humayun, M. S.; Sadda, S. R.; Thompson, C. A.; Olivier, S. S. & Kartz, M. W.
Object Type: Report
System: The UNT Digital Library
R-Matrix Evaluation of 16O Neutron Cross Sections up to 6.3 MeV (open access)

R-Matrix Evaluation of 16O Neutron Cross Sections up to 6.3 MeV

In this paper we describe an evaluation of {sup 16}O neutron cross sections in the resolved resonance region with the multilevel Reich-Moore R-matrix formalism. Resonance analyses were performed with the computer code SAMMY [LA98] which utilizes Bayes method, a generalized least squares technique. Over the years the nuclear community has developed a collection of evaluated nuclear data for applications in thermal, fast reactor, and fusion systems. However, typical neutron spectra in criticality safety applications are different from the spectra relevant to thermal, fast reactor, and fusion systems. In fact, the neutron spectra important for these non-reactor systems appear to peak in the epithermal energy range. Nuclear data play a major role in the calculation of the criticality safety margins for these systems. A thorough examination of how the present collection of nuclear data evaluations behaves in criticality safety calculations is needed. Many older evaluations will probably need to be revised, and new evaluations will be needed. Oxygen is an important element in criticality safety applications where oxides are present in significant abundance. The existing ENDF/B-VI.5 evaluation is expressed in terms of point-wise cross sections derived from the analysis of G. Hale [HA91]. Unfortunately such an evaluation is not directly useful …
Date: August 21, 2000
Creator: Sayer, R.O.
Object Type: Report
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 3, Ed. 1 Monday, August 21, 2000 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 84, No. 3, Ed. 1 Monday, August 21, 2000

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: August 21, 2000
Creator: McFall, Amy
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 78, No. 268, Ed. 1 Monday, August 21, 2000 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 78, No. 268, Ed. 1 Monday, August 21, 2000

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 21, 2000
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 101, No. 139, Ed. 1 Monday, August 21, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 139, Ed. 1 Monday, August 21, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 21, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 109, No. 68, Ed. 1 Monday, August 21, 2000 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 109, No. 68, Ed. 1 Monday, August 21, 2000

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: August 21, 2000
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Results of the Independent Radiological Verification Survey of Remediation at Building 14, Former Linde Uranium Refinery, Tonawanda, New York (LI001V) (open access)

Results of the Independent Radiological Verification Survey of Remediation at Building 14, Former Linde Uranium Refinery, Tonawanda, New York (LI001V)

As part of the Formerly Utilized Sites Remedial Action Program, a team from Oak Ridge National Laboratory (ORNL) conducted a radiological verification survey of Building 14 at the former Linde Uranium Refinery, Tonawanda, New York. The purpose of the survey was to verify that remedial action completed by the project management contractor had reduced contamination levels to within authorized limits. Prior to remediation, fixed and removable beta-gamma emitting material was Prevalent throughout Building 14 and in some of the process piping. Decontamination consisted of removal of surface contamination from floors, floor-wall interfaces, walls, wall-ceiling interfaces, and overhead areas; decontamination or removal of process piping; excavation and removal of subsurface soil; and vacuuming of dust. This independent radiological assessment was performed to verify that the remedial action had reduced contamination levels to within authorized limits. Building 14 at the former Linde site in Tonawanda, New York, was thoroughly investigated inside for radionuclide residues. Surface residual activity levels were generally well below applicable guidelines for protection against radiation. Similarly, removable alpha and beta-gamma activity levels were below guidelines. Gamma exposure rates within the building were at typical background levels, and no elevated indoor radon concentrations were measured. However, numerous areas exceeding U.S. …
Date: August 21, 2000
Creator: McKenzie, S.P.
Object Type: Report
System: The UNT Digital Library
Electron Beam Welding of a Depleted Uranium Alloy to Niobium Using a Calibrated Electron Beam Power Density Distribution (open access)

Electron Beam Welding of a Depleted Uranium Alloy to Niobium Using a Calibrated Electron Beam Power Density Distribution

Electron beam test welds were made joining flat plates of commercially pure niobium to a uranium-6wt%Nb (binary) alloy. The welding parameters and joint design were specifically developed to minimize mixing of the niobium with the U-6%Nb alloy. A Modified Faraday Cup (MFC) technique using computer-assisted tomography was employed to determine the precise power distribution of the electron beam so that the welding parameters could be directly transferred to other welding machines and/or to other facilities.
Date: August 21, 2000
Creator: Elmer, J.W.; Teruya, A.T. & Terrill, P.E.
Object Type: Report
System: The UNT Digital Library
Self-Consistent Integral Equation Theory for Polyolefins: Comparison to Molecular Dynamics Simulations and X-Ray Scattering (open access)

Self-Consistent Integral Equation Theory for Polyolefins: Comparison to Molecular Dynamics Simulations and X-Ray Scattering

None
Date: August 21, 2000
Creator: Putz, Mathias; Curro, John G. & Grest, Gary S.
Object Type: Article
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 288, Ed. 1 Monday, August 21, 2000 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 288, Ed. 1 Monday, August 21, 2000

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: August 21, 2000
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History