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[Newspaper Article: Railroad and Pioneer Museum slates benefit luncheon for Santa Fe depot] (open access)

[Newspaper Article: Railroad and Pioneer Museum slates benefit luncheon for Santa Fe depot]

Newspaper article about a luncheon planned by the Temple Railroad and Pioneer Museum to raise money for the restoration of historic downtown Temple. Included with the article is a photo of the Santa Fe depot before World War I.
Date: May 10, 1996
Creator: Ray, Randy
System: The Portal to Texas History
The effects of silicon doping on the performance of PMAN carbon anodes in Li-ion cells (open access)

The effects of silicon doping on the performance of PMAN carbon anodes in Li-ion cells

Carbons derived from polymethylacrylonitrile (PMAN) have been studied for use as intercalation anodes in Li-ion cells. The effect of Si doping upon the electrochemical performance of PMAN carbons was studied using tetravinylsilane (TVS) and tetramethysilane (TMS) as sources of Si during the formation of the PMAN precursors. The carbons were characterized by galvanostatic cycling, cyclic voltammetry, and complex impedance. The presence of 9 to 11 w/o Si in the PMAN lattice greatly increased the irreversible capacity of these materials.
Date: May 1, 1996
Creator: Guidotti, Ronald A.; Johnson, Bryan J. & Even, William, Jr.
System: The UNT Digital Library
Getting to necessary and sufficient-developing accident scenarios for risk assessment (open access)

Getting to necessary and sufficient-developing accident scenarios for risk assessment

This paper presents a simple, systematic approach for developing accident scenarios using generic accident types. Result is a necessary and sufficient set of accident scenarios that can be used to establish the safety envelope for a facility or operation. Us of this approach along with the methodology of SAND95-0320 will yield more consistent accident analyses between facilities and provide a sound basis for allocating limited risk reduction resources.
Date: May 1, 1996
Creator: Mahn, Jeffrey A.
System: The UNT Digital Library
Expanding the role of internal facility assessments (open access)

Expanding the role of internal facility assessments

The US Air Force (USAF) Environmental Compliance Assessment and Management Program (ECAMP) is an effective and comprehensive system to evaluate environmental compliance at individual USAF installations. The ECAMP assessment is typically performed by a team of experts from the installation`s Major Command (MAJCOM) Headquarters, and is often augmented with technical contractor support. As directed by Air Force policy, an external ECAMP assessment is required at a minimum of every three years for each installation. In the intervening years, each installation is required to perform an internal ECAMP assessment, with its own personnel and resources. Even though team composition differs, the internal and external ECAMP assessments are likely to be very similar in scope, objectives, and deliverables. For over nine years, Argonne National Laboratory (ANL) has supported several Air Force MAJCOMs in performing their external ECAMP assessments. More recently, ANL has also had the opportunity to provide technical support and training at individual installations during their preparation and conduct of internal ECAMP assessments. From that experience, the authors have learned that the quality and value of the internal assessment is enhanced by making it a vehicle for training, planning, and interaction among organizations. Various strategies and techniques have been successfully employed …
Date: May 1, 1996
Creator: Kolpa, Ronald L.; Levenson, James B. & Weaver, Marja A.
System: The UNT Digital Library
Evaluating the quality and effectiveness of hazardous waste training programs (open access)

Evaluating the quality and effectiveness of hazardous waste training programs

An installation`s compliance with Resource Conservation and Recovery Act (RCRA) hazardous waste regulations is strongly dependent on the knowledge, skill, and behavior of all individuals involved in the generation and management of hazardous waste. Recognizing this, Headquarters Air Force Materiel Command (HQ/AFMC) determined that an in-depth evaluation of hazardous waste training programs at each AFMC installation was an appropriate element in assessing the overall effectiveness of installation hazardous waste management programs in preventing noncompliant conditions. Consequently, pursuant to its authority under Air Force Instruction (AFI) 32-7042, Solid and Hazardous Waste Compliance (May 12, 1994) to support and maintain hazardous waste training, HQ/AFMC directed Argonne National Laboratory to undertake the Hazardous Waste Training Initiative. This paper summarizes the methodology employed in performing the evaluation and presents the initiative`s salient conclusions.
Date: May 1, 1996
Creator: Kolpa, Ronald L.; Haffenden, Rebecca A. & Weaver, Marja A.
System: The UNT Digital Library
A general protocol for restoration of entire river catchments (open access)

A general protocol for restoration of entire river catchments

Large catchment basins may be viewed as ecosystems with interactive natural and cultural attributes. Stream regulation severs ecological connectivity between channels and flood plains by reducing the range of natural flow and temperature variation, reduces the capacity of the ecosystem to sustain native biodiversity and bioproduction and promotes proliferation of non-native biota. However, regulated rivers regain normative attributes, which promote recovery of native biota, as distance from the dam increases and in relation to the mode of regulation. Therefore, reregulation of flow and temperature to normative pattern, coupled with elimination of pollutants and constrainment of nonnative biota, can naturally restore damaged habitats from headwaters to mouth. The expectation is rapid recovery of depressed populations of native species. The protocol requires: restoration of seasonal temperature patterns; restoration of peak flows needed to reconnect and periodically reconfigure channel and floodplain habitats; stabilization of base flows to revitalize the shallow water habitats; maximization of dam passage to allow restoration of metapopulation structure; change in the management belief system to rely on natural habitat restoration as opposed to artificial propagation, installation of artificial instream structures (river engineering) and artificial food web control; and, practice of adaptive ecosystem management.
Date: May 28, 1996
Creator: Stanford, Jack A.; Frissell, Christopher A.; Ward, J. V.; Liss, William J.; Coutant, Charles C.; Williams, Richard N. et al.
System: The UNT Digital Library
Selective, pulsed CVD of platinum on microfilament gas sensors (open access)

Selective, pulsed CVD of platinum on microfilament gas sensors

A post-processing, selective micro-chemical vapor deposition (``micro-CVD``) technology for the deposition of catalytic films on surface-micromachined, nitride-passivated polysilicon filaments has been investigated. Atmospheric pressure deposition of Pt on microfilaments was accomplished by thermal decomposition of Pt acetylacetonate; deposition occurs selectively only on those filaments which are electrically heated. Catalyst morphology, characterized by SEM, can be controlled by altering deposition time, filament temperature, and through the use of pulsed heating of the filament during deposition. Morphology plays an important role in determining the sensitivity of these devices when used as combustible gas sensors.
Date: May 1, 1996
Creator: Manginell, Ronald P.; Smith, James H.; Ricco, Antonio J.; Moreno, Daniel J.; Hughes, Robert C.; Huber, Robert J. et al.
System: The UNT Digital Library
New developments in fluorofullerenes chemistry (open access)

New developments in fluorofullerenes chemistry

Flurofullerenes were among the first chemical derivatives prepared from new spherical forms of carbon, yet it took 3 years of research to isolate the first single compound, C{sub 60}F{sub 48}. Subsequent studies provided a better understanding of physical and chemical properties of this compound. Here we present new data concerning synthesis, reactions, and properties of C{sub 60}F{sub 48}.
Date: May 1, 1996
Creator: Gakh, Andrei A.; Sachleben, Richard A.; Hagaman, Edward W. & Tuinman, Albert A.
System: The UNT Digital Library
Development of sol-gel derived coating for NICALON{sup TM}/SiC composites (open access)

Development of sol-gel derived coating for NICALON{sup TM}/SiC composites

Mullite and aluminum titanate precursor polymeric sols were developed for applying as coatings on Nicalon{trademark} fabrics and tows. A Nicalon{trademark}/SiC composite with a mullite interface was fabricated. The mullite precursor interface coatings were applied by a vacuum infiltration method and the SiC matrix was deposited by a forced flow chemical vapor infiltration process. Thin, uniform mullite interface coatings were obtained. However, the Nicalon{trademark}/SiC composite exhibited brittle fracture. Mullite and alumina-titania coatings were applied on Nicalon{trademark} tows and the effect of heat treatment at 1000{degrees}C in air is discussed.
Date: May 1, 1996
Creator: Shanmugham, S.; Liaw, P. K.; Stinton, D. P.; Besmann, T. M.; More, K. L.; Bleier, A. et al.
System: The UNT Digital Library
Experimental Investigation of the Classical Rayleigh-Taylor Instability (open access)

Experimental Investigation of the Classical Rayleigh-Taylor Instability

The evolution of the Rayleigh-Taylor (RT) instability in a compressible medium has been investigated at an accelerating embedded interface and at the ablation front in a series of experiments on the Nova laser. The x-ray drive generated in a gold hohlraum ablatively accelerated a planar target consisting of a doped plastic pusher backed by a higher density titanium payload with perturbations placed at the plastic-Ti interface. The targets were diagnosed by face-on and side-on radiography. In previous work focusing on single mode perturbations, wavelengths as short as 10 m have been observed to grow strongly at the embedded interface. Here multimode perturbations consisting of either 2, 10 or 20 modes superposed in phase have been investigated.
Date: May 21, 1996
Creator: Budil, K. S.; Remington, B. A.; Peyser, T. A.; Mikaelian, K. O.; Rubenchik, A. M.; Berning, M. et al.
System: The UNT Digital Library
Spatial Resolution of Gated X-Ray Pinhole Cameras (open access)

Spatial Resolution of Gated X-Ray Pinhole Cameras

The new camera FXI was investigated. Spatial resolution, or its Fourier transform, the modulation transfer function (MTF), is critical for quantitative interpretation of recent hydrodynamic instability data taken on the Nova laser. We have taken data corresponding to backlit straight edges, pinholes, and grids, both on the bench and {ital in}{ital situ} on Nova. For both the pinhole and edge data, the MTF at all wavelengths of interest can be deduced from a single image. Grids are of more limited usefulness, giving the MTF value only at the spatial period of the grid. These different techniques for characterizing the MTF of gated x-ray pinhole cameras are discussed, with results specific to the FXI presented.
Date: May 15, 1996
Creator: Robey, H. F.; Budil, K. S. & Remington, B. A.
System: The UNT Digital Library
What is the potential predictability of seasonal floods and droughts? (open access)

What is the potential predictability of seasonal floods and droughts?

The potential predictability (PP) of seasonal anomalies in continental hydrology may be thought of as the upper bound in forecast accuracy to be expected when the state of the oceans is known perfectly. We assume that the PP of the seasonal anomalies of continental hydrology is related to their degree of reproducibility in the presence of identical ocean boundary conditions across a number of simulations. In this study, the PP of seasonal anomalies in surface hydrological variables is estimated from an ensemble of 6 decadal integration of the ECMWF global atmospheric model coupled to a land-surface scheme which includes interception and transpiration by a simple vegetation canopy. Identical observed (AMIP) monthly sea surface temperatures are specified in each simulation, while the initial condition of the atmosphere and land surface are allowed to vary.
Date: May 1, 1996
Creator: Phillips, T. J.
System: The UNT Digital Library
Testing of an impedance heating system for solar power tower applications (open access)

Testing of an impedance heating system for solar power tower applications

A non-conventional type of heating system is being tested at Sandia National Laboratories for solar thermal power tower applications. In this system, called impedance heating, electric current flows directly through the pipe to maintain the desired temperature. The pipe becomes the resistor where the heat is generated. Impedance heating has many advantages over previously used mineral insulated (MI) heat trace. An impedance heating system should be much more reliable than heat trace cable since delicate junctions and cabling are not used and the main component, a transformer, is inherently reliable. A big advantage of impedance heating is the system can be sized to rapidly heat up the piping to provide rapid response times necessary in cyclic power plants such as solar power towers. In this paper, experimental results from testing an impedance heating system are compared to MI cable heat trace. We found impedance heating was able to heat piping rapidly and effectively. There were not significant stray currents and impedance heating did not affect instrumentation.
Date: May 1, 1996
Creator: Pacheco, James E. & Kolb, William J.
System: The UNT Digital Library
A three-dimensional nodal neutron kinetics capability for relaps (open access)

A three-dimensional nodal neutron kinetics capability for relaps

The incorporation of a three-dimensional neutron kinetics capability into the DOE version of the RELAP5/MOD3.2 reactor safety code is discussed. A brief discussion of the kinetics method is given along with a discussion of the cross section parameterization models available in RELAP5/MOD3.2. The RELAP5/MOD3.2 code is then used to perform calculations of the NEACRP rod ejection and rod withdrawal benchmarks, and results are presented.
Date: May 1, 1996
Creator: Judd, J. L. & Weaver, W. L.
System: The UNT Digital Library
High current RF shield for PEP-II vacuum system expansion joint (open access)

High current RF shield for PEP-II vacuum system expansion joint

A novel RF shield was developed for the circular expansion joint used throughout the PEP-II vacuum system straight sections. Existing RF shield designs, used in accelerators/storage rings throughout the world, have been the source of many failures at beam currents much smaller than the 3 amps planned for PEP-II. This RF shield uses a unique spring-loaded finger mechanism to maintain proper electrical contact across the joint, accommodate 1.5 mm transverse and 32 mm longitudinal excursions, while minimizing geometry-driven trapped-mode RF heating at GHz frequencies. Alumina-dispersed, copper alloy fingers are used to maintain desired mechanical properties at higher temperatures instead of the more commonly used beryllium-copper alloys. A prototype expansion joint was assembled, mechanically tested, and subjected to 200% of the expected operational RF load. This RF shield design can be easily adapted to non-circular geometries.
Date: May 1996
Creator: Belser, F. C.; Berg, J. D. & Kerns, J.
System: The UNT Digital Library
A fast CCD detector for charge exchange recombination spectroscopy on the DIII-D tokamak (open access)

A fast CCD detector for charge exchange recombination spectroscopy on the DIII-D tokamak

Charge Exchange Recombination (CER) spectroscopy has become a standard diagnostic for tokamaks. CER measurements have been used to determine spatially and temporally resolved ion temperature, toroidal and poloidal ion rotation speed, impurity density and radial electric field. Knowledge of the spatial profile and temporal evolution of the electric field shear in the plasma edge is crucial to understanding the physics of the L to H transition. High speed CER measurements are also valuable for Edge Localized Mode (ELM) studies. Since the 0.52 ms minimum time resolution of our present system is barely adequate to study the time evolution of these phenomena, we have developed a new CCD detector system with about a factor of two better time resolution. In addition, our existing system detects sufficient photons to utilize the shortest time resolution only under exceptional conditions. The new CCD detector has a quantum efficiency of about 0.65, which is a factor of 7 better than our previous image intensifier-silicon photodiode detector systems. We have also equipped the new system with spectrometers of lower f/number. This combination should allow more routine operation at the minimum integration time, as well as improving data quality for measurements in the divertor-relevant region outside of …
Date: May 1996
Creator: Thomas, D. M.; Burrell, K. H.; Groebner, R. J. & Gohil, P.
System: The UNT Digital Library
Recent advances in phosphate laser glasses for high power applications (open access)

Recent advances in phosphate laser glasses for high power applications

Recent advances in Nd-doped phosphate laser glasses for high-peak-power and high-average-power applications are reviewed. Compositional studies have progressed to the point that glasses can be tailored to have specific properties for specific applications. Non-radiative relaxation effects can be accurately modeled and empirical expressions have been developed to evaluate both intrinsic (structural) and extrinsic (contamination induced) relaxation effects. Losses due to surface scattering and bulk glass absorption have been carefully measured and can be accurately predicted. Improvements in processing have lead to high damage threshold (e.g. Pt inclusion free) and high thermal shock resistant glasses with improved edge claddings. High optical quality pieces up to 79 x 45 x 4cm{sup 3} have been made and methods for continuous melting laser glass are under development.
Date: May 14, 1996
Creator: Campbell, J.H.
System: The UNT Digital Library
Forming and smoothing D{sub 2} and HD layers for ICF by infra-red heating (open access)

Forming and smoothing D{sub 2} and HD layers for ICF by infra-red heating

We describe a technique to form and smooth uniform solid D{sub 2}, HD or DT layers for inertial confinement fusion targets. Pumping the infrared (IR) collision induced vibration-rotation band generates a bulk heating of the solid. Shadowgraphs reveal that this bulk heat quickly redistributes the solid into a relatively uniform layer depending on the IR intensity profile. Measured redistribution time constants are used to determine the conversion efficiency of IR light into bulk heat. Phase shifting interferometry reveals that the surface roughness decreases with increasing IR heating.
Date: May 31, 1996
Creator: Collins, G.W.; Tiszauer, D.; Feit, M.; Mapoles, E.R.; Bernat, T.P.; Bittner, D.N. et al.
System: The UNT Digital Library
Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report. (open access)

Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report.

This report contains the proceedings of a workshop held during 1995 in Portland, Oregon. The objective of the workshop was to assemble a group of experts that could help us define carrying capacity for Columbia River Basin salmonids. The workshop was one activity designed to answer the questions asked in Measure 7.1A of the Council`s Fish and Wildlife Program. Based, in part, on the information we learned during the workshop we concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. Measure 7.1A requires a definition of carrying capacity and a list of determinants (limiting factors) of capacity. The implication or inference then follows that by asking what we know and do not know about the determinants will lead to research that increases our understanding of what is limiting salmon survival. It is then assumed that research results will point to management actions that can remove or repair the limiting factors. Most ecologists and fisheries scientists that have studied carrying capacity clearly conclude that this approach is an oversimplification of complex ecological processes. To pursue the capacity parameter, that is, a single number or set of …
Date: May 1996
Creator: Johnson, Gary E.; Neitzel, D. A. & Mavros, William V.
System: The UNT Digital Library
Recent progress in InGaAsSb/GaSb TPV devices (open access)

Recent progress in InGaAsSb/GaSb TPV devices

AstroPower is developing InGaAsSb thermophotovoltaic (TPV) devices. This photovoltaic cell is a two-layer epitaxial InGaAsSb structure formed by liquid-phase epitaxy on a GaSb substrate. The (direct) bandgap of the In{sub 1{minus}x}Ga{sub x}As{sub 1{minus}y}Sb{sub y} alloy is 0.50 to 0.55 eV, depending on its exact alloy composition (x,y); and is closely lattice-matched to the GaSb substrate. The use of the quaternary alloy, as opposed to a ternary alloy--such as, for example InGaAs/InP--permits low bandgap devices optimized for 1,000 to 1,500 C thermal sources with, at the same time, near-exact lattice matching to the GaSb substrate. Lattice matching is important since even a small degree of lattice mismatch degrades device performance and reliability and increases processing complexity. Internal quantum efficiencies as high as 95% have been measured at a wavelength of 2 microns. At 1 micron wavelengths, internal quantum efficiencies of 55% have been observed. The open-circuit voltage at currents of 0.3 A/cm{sup 2} is 0.220 volts and 0.280 V for current densities of 2 A/cm{sup 2}. Fill factors of 56% have been measured at 60 mA/cm{sup 2}. However, as current density increases there is some decrease in fill factor. The results to date show that the GaSb-based quaternary compounds provide a …
Date: May 1, 1996
Creator: Shellenbarger, Z. A.; Mauk, M. G.; DiNetta, L. C. & Charache, G. W.
System: The UNT Digital Library
Working with the superabrasives industry to optimize tooling for grinding brittle materials (open access)

Working with the superabrasives industry to optimize tooling for grinding brittle materials

The optics manufacturing industry is undertaking a significant modernization, as computer-numeric-controlled (CNC) equipment is joining or replacing open-loop equipment and hand lapping/polishing on the shop floor. Several prototype CNC lens grinding platforms employing ring tools are undergoing development and demonstration at the Center for Optics Manufacturing in Rochester, NY, and several machine tool companies have CNC product lines aimed at the optics industry. Benefits to using CNC ring tool grinding equipment include: essentially unlimited flexibility in selecting radii of curvature without special radiused tooling, the potential for CIM linkages to CAD workstations, and the cultural shift from craftsmen with undocumented procedures to CNC machine operators employing computerized routines for process control. In recent years, these developments, have inspired a number of US optics companies to invest in CNC equipment and participate in process development activities involving bound diamond tooling. This modernization process,extends beyond large optics companies that have historically embraced advanced equipment, to also include smaller optical shops where a shift to CNC equipment requires a significant company commitment. This paper addresses our efforts to optimize fine grinding wheels to support the new generation of CNC equipment. We begin with a discussion of how fine grinding fits into the optical …
Date: May 1, 1996
Creator: Taylor, J. S.; Piscotty, M. A.; Blaedel, K. L. & Gray, F. A.
System: The UNT Digital Library
Positron beam lifetime spectroscopy of atomic scale defect distributions in bulk and microscopic volumes (open access)

Positron beam lifetime spectroscopy of atomic scale defect distributions in bulk and microscopic volumes

We are developing a defect analysis capability based on two positron beam lifetime spectrometers: the first is based on a 3 MeV electrostatic accelerator and the second on our high current linac beam. The high energy beam lifetime spectrometer is operational and positron lifetime analysis is performed with a 3 MeV positron beam on thick samples. It is being used for bulk sample analysis and analysis of samples encapsulated in controlled environments for {ital in}{ital situ} measurements. A second, low energy, microscopically focused, pulsed positron beam for defect analysis by positron lifetime spectroscopies is under development at the LLNL high current positron source. This beam will enable defect specific, 3-D maps of defect concentration with sub-micron location resolution and when coupled with first principles calculations of defect specific positron lifetimes it will enable new levels of defect concentration mapping and defect identification.
Date: May 1, 1996
Creator: Howell, R. H.; Cowan, T. E.; Hartley, J.; Sterne, P. & Brown, B.
System: The UNT Digital Library
Photoelectron emission microscopy and its application to the study of polymer surfaces (open access)

Photoelectron emission microscopy and its application to the study of polymer surfaces

The X-ray Photoelectron Emission Microscopy (X-PEEM) at the Advanced Light Source (ALS) has a spatial resolution of 0.2 microns at an accelerating voltage of 12kV. The tunability of the photon energy is used to provide chemical state information using near edge X-ray absorption fine structure (NEXAFS) spectroscopy on the sub-micrometer scale. The homogeneity of thin films of polymer blends was studied for various film thicknesses. The polystyrene/polyvinylmethylether film of 194 {angstrom} showed protrusions of 2-3{mu}m diameter with an enriched polystyrene content while the polystyrene/polystyreneacrylonitrile 504 {angstrom} thick films showed 5-6 {mu}m segregated regions without any topological structure.
Date: May 1, 1996
Creator: Cossy-Favre, A.; Diaz, J.; Anders, S. & Padmore, H.A.
System: The UNT Digital Library
The Hanford spent nuclear metal fuel multi-canister overpack and vacuum drying {ampersand} hot conditioning process (open access)

The Hanford spent nuclear metal fuel multi-canister overpack and vacuum drying {ampersand} hot conditioning process

Nuclear production reactors operated at the U.S. Department of Energy`s Hanford Site from 1944 until 1988 to produce plutonium. Most of the irradiated fuel from these reactors was processed onsite to separate and recover the plutonium. When the processing facilities were closed in 1992, about 1,900 metric tons of unprocessed irradiated fuel remained in storage. Additional fuel was irradiated for research purposes or was shipped to the Hanford Site from offsite reactor facilities for storage or recovery of nuclear materials. The fuel inventory now in storage at the Hanford Site is predominantly N Reactor irradiated fuel, a metallic uranium alloy that is coextruded into zircaloy-2 cladding. The Spent Nuclear Fuel Project has rommitted to an accelerated schedule for removing spent nuclear fuel from the Hanford Site K Basins to a new interim storage facility in the 200 Area. Under the current proposed accelerated schedule, retrieval of spent nuclear fuel stored in the K East and West Basins must begin by December 1997 and be completed by December 1999. A key part of this action is retrieving fuel canisters from the water-filled K Basin storage pools and transferring them into multi@ister overpacks (MCOS) that will be used to handle and process …
Date: May 15, 1996
Creator: Irwin, J.J.
System: The UNT Digital Library