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open access

Visual simulation of radiographs

Description: A method for computer simulation of radiographs has been added to the LLNL version of the solid modeler TIPS-1 (Technical Information Processing System-1). This new tool will enable an engineer to compare an actual radiograph of a solid to its computer-generated counterpart. The appearance of discrepancies between the two can be an indication of flaws in the solid object. Simulated radiographs can also be used to preview the placement of x-ray sources to focus on areas of concern before actual radiographs are made.
Date: January 18, 1985
Creator: Laguna, G.
Partner: UNT Libraries Government Documents Department

TRAC, FDSys and putting it all together

Description: This presentation discusses TRAC, an open source web-based project management and bug tracking system, and the Federated Digital System (FDSys), an advanced digital system that authenticates, preserves, versions, and provides permanent public access to federal government information.
Date: October 18, 2011
Creator: Phillips, Mark Edward
Partner: UNT Libraries
open access

PWR decontamination feasibility study

Description: The decontamination work which has been accomplished is reviewed and it is concluded that it is worthwhile to investigate further four methods for decontamination for future demonstration. These are: dilute chemical; single stage strong chemical; redox processes; and redox/chemical in combination. Laboratory work is recommended to define the agents and processes for demonstration and to determine the effect of the solvents on PWR materials. The feasibility of Indian Point 1 for decontamination demonstrations is discussed, and it is shown that the system components of Indian Point 1 are well suited for use in demonstrations.
Date: December 18, 1978
Creator: Silliman, P.L.
Partner: UNT Libraries Government Documents Department
open access

Application of Time Domain PARET to the measured responses of a building

Description: The application of the Time Domain PARET (TDP) algorithm to data obtained from the measured responses of a three story reinforced concrete building approximately 465 feet long by 220 feet wide by 40 feet high, with 12 to 18 inch thick walls, is described. The measurements were taken by Agbabian Associates, El Segundo, California. The structure was excited by a device developed at Agbabian that uses a mass sliding down a rod to cut metal disks attached to the rod. The result is a series of impulse forces driving the building at the attachment point of the rod. The responses measured were the accelerations at two locations on the structure. A constraint imposed was that the equipment in the building must remain operating during the time the measurements were made.
Date: September 18, 1979
Creator: Lager, D.L.
Partner: UNT Libraries Government Documents Department
open access

Some features of Rayleigh scattering from light atoms and ions

Description: When photon energies are well below 1 MeV the only significant contribution to elastic (coherent) photon-atom scattering comes from Rayleigh scattering, the elastic scattering of photons from bound atomic electrons. This report discusses the Rayleigh scattering cross sections for atoms and ions of low nuclear charge, particularly for photon energies in the vicinity of the threshold for photoionization from the K-shell. Just below this threshold energy there is a sequence of resonances in the elastic scattering amplitude. Each resonance occurs at an energy corresponding to the excitation of a K-shell electron to a higher unfilled shell. For a multi-electron atom the total cross section can go through a near zero minimum just below the resonance region due to interference between K and L amplitudes. The resonance region expands with increasing ionization, on the low side as more interior shells become unfilled and accessible, and, on the high side as the ionization threshold increases. Above the ionization threshold, in an isonuclear sequence the K-shell amplitudes share a common curve differing only in the position of the threshold. When the K-shell is opened the amplitude departs from this common curve. Above, but near, threshold the imaginary part of the K-shell amplitude is important but it rapidly decreases. Well above the threshold form factor predictions are approached for the atom and for the scattering from each subshell separately.
Date: July 18, 1979
Creator: Parker, J.C. & Pratt, R.H.
Partner: UNT Libraries Government Documents Department
open access

Review of the beta situation

Description: This note lists some of the possible causes of beta limitation in tokamak and discusses what is known and what is involved in investigating them. The motivation for preparing this note is the observed degradation of confinement with increasing beta poloidal ..beta../sub p/ and beam power P/sub b/ in ISX-B.
Date: January 18, 1982
Creator: Sheffield, J.
Partner: UNT Libraries Government Documents Department
open access

Workshop on tritium safety and environmental effects, October 15--17, 1990, Aiken, South Carolina: Session summaries

Description: A meeting was held on October 15, 16, 17, 1990 to discuss the state of tritium safety and environmental effects. The meeting was organized with the help of the International Energy Agency planning committee consisting of K. Steinmetz, Y. Seki, G. Nardella, and G. Vivian. Representative of tritium production facilities and heavy water reactor power production were also involved. The meeting was organized to address seven topics in tritium safety that were thought to require further work. The topics were: (1) materials science, (2) environmental models, (3) environmental model validation, (4) tritiated organic compounds, (5) human dosimetry, (6) tritium sampling and measurement, and (7) long-term environmental databases.
Date: April 18, 1991
Creator: Murphy, C.E. Jr. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Feasibility of laser-separation of /sup 36/S and its use as an atmospheric tracer

Description: This report addresses one of the possible uses of isotopic tracers, produced by laser-assisted iostope separation, in the investigation of pollution problems. Specifically, the use of laser-produced sulfur isotopes to analyze the acid rain situation is considered as it is a most important application of this technique. The proposed use of isotopically-labelled SO/sub 2/, in particular of /sup 36/SO/sub 2/, as a tracer can help elucidate the chemical and transport facets in a unified experiment. Separation of a sufficient quantity of the rare /sup 36/S isotope to perform several of these tracer studies appears to be practical and economical. This overall process is certainly deserving of further investigation.
Date: August 18, 1981
Creator: Herman, I.P.
Partner: UNT Libraries Government Documents Department
open access

Radio frequency and microwave plasma for optical thin film deposition

Description: For the next generation of fusion lasers reflecting mirrors with laser damage thresholds of at least 40 J/cm{sup 2} for 10 ns laser pulses at 1.064 {mu}m are needed. Up to now, no deposition technique has been developed to produce such mirrors. Best R D-values realized today are around 30 J/cm{sup 2} for e-beam evaporated mirrors. R D on conventional e-beam coating processes over the last 10 years has come up with marginal improvements in laser damage thresholds only. However, new technologies, like PICVD developed for the fabrication of ultra-low loss fiber preforms, seem to offer the potential to solve this problem. It is well known that fused silica produced by CVD processes can have laser damage thresholds as high as 80 J/cm{sup 2}. However, the thickness of a single deposited film is in the {mu}m-range for most of the CVD processes used for preform manufacturing; since interference optics need films in the{lambda}/4n range the use of preform-fabrication processes for the purpose of interference mirror fabrication is limited to a few plasma based CVD technologies, namely PCVD. Especially PICVD is a very powerful technology to fabricate thin film multilayers for interference mirrors, because this technique is able to produce films down to monolayer thickness with nearly perfect stoichiometry and morphology. In first and preliminary experiments the usual deposition in a circular tube at high temperatures has been used for simplicity. However, to produce large area high quality laser mirrors this principle know-how has to be transferred from circular to planar geometry. Experiments showed, that there may be some limitations with respect to the homogeneity of a planar deposition using microwave excitation for the plasma. Therefore experiments have been performed in parallel with both RF and microwave excitation for comparison. In the following we will restrict ourselves to the description and …
Date: October 18, 1990
Creator: Otto, J.; Paquet, V.; Kersten, R.T.; Etzkorn, J.W. (Schott Glaswerke, Mainz (Germany, F.R.)); Brusasco, R.M.; Britten, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Inertial effects in laser-driven ablation

Description: The gasdynamic partial differential equations (PDE's) governing the motion of an ablatively accelerated target (rocket) contain an inertial force term that arises mathematically from acceleration of the reference frame in which the PDE's are written, and more physically from the requirement that part of the ablated mass (the deflagration wave zone) needs to be accelerated along with the unablated mass (payload). We give a simple, intuitive description of this effect, and estimate its magnitude and parametric dependences by means of approximate analytical formulas inferred from our computer hydrocode calculations. Often this inertial term is negligible, but for problems in the areas of laser fusion and laser equation of state studies we find that it can reduce the attainable hydrodynamic efficiency of acceleration and implosion by up to 25% for typical conditions.
Date: August 18, 1983
Creator: Harrach, R. J.; Szoeke, A. & Howard, W. M.
Partner: UNT Libraries Government Documents Department
open access

Computer modeling of nuclear waste storage canister corrosion

Description: Current plans for nuclear waste disposal include placing the waste in a canister to isolate it from the repository environment for 1000 years. Corrosion prediction techniques are currently inadequate to quarantee the canister performance over this length of time. We are attempting to better predict the corrosion process with the help of computer modeling. We developed a program to calculate anodic and cathodic polarization curves using Tafel slopes, equilibrium exchange current densities, and other electrochemical parameters obtained from the experimental corrosion literature. The model generates and displays polarization curves for different values of environmetal parameters such as temperature, pH, and concentrations of pertinent species in the vicinity of the canister material. For the case of uniform corrosion in acidic media, our model predicts corrosion rates in fair agreement with literature values.
Date: October 18, 1979
Creator: Cottrell, P.T.; Ludemann, W.D. & McCright, R.D.
Partner: UNT Libraries Government Documents Department

Faculty Recital: 2007-01-18 - Lynn Eustis, soprano

Description: Faculty Recital performed at the UNT College of Music Recital Hall titled, "Vocal Music in Theresienstadt: Art as a Means of Survival"
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: January 18, 2007
Duration: 23 minutes 38 seconds
Creator: Eustis, Lynn & Markina, Anastasia
Partner: UNT Music Library
open access

Investigations of charge-separation processes in metal complexes

Description: The major thrust of the research has been the quantification of the excited states of inorganic complexes that display potential for mediating charge-separation processes. Investigations of copper(1) mixed-ligand complexes have been completed. Non-equilibrated emitting states have been assigned. Chemical tuning of the emission energy by modifying the basicity of the donor ligand on the metal has been achieved. Structure-property relationships have been defined for crystalline complexes of zinc containing both diimine and monothiol ligands. Correlation of the spectral shifts with the rotations of the thiol phenyl rings in different crystal phases has been shown by comparing with extended Huckel calculations and x-ray structures. Complexes of zinc containing diimine and dithiol ligands are shown to be polynuclear species. A trinuclear species can be forced to assume a binuclear structure by incorporating other non-coordinating ligands into the lattice. The transformation is accompanied by substantial photophysical changes. Syntheses and x-ray structure determinations of platinum(2) complexes containing diimine ligands only, both diimine and dithiol ligands, and dithiol ligands only have been completed. An unusual platinum(3) bis(dithiol) species has been obtained and its structure determined. Investigations of the emission spectra of bis(bipyridine)platinum(2) have revealed the existence of multiple emitting states with both ligand-localized and charge- transfer characteristics.
Date: February 18, 1991
Creator: Crosby, G.A.
Partner: UNT Libraries Government Documents Department

Lampsilis teres, Specimen #378

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; olive external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 100 - 120 mm in length and was assessed to be recently dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Tritogonia verrucosa, Specimen #897

Description: One preserved mussel specimen including the left valve only. The specimen exhibits an elliptical shape; thick shell; white internal coloring; brown external coloring; external sculpturing in the form of pustules. Collected in the Trinity basin. The specimen measures between 60 - 100 mm in length and was assessed to be long dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Quadrula mortoni, Specimen #982

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Quadrula mortoni, Specimen #983

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; moderately thick shell; white internal coloring; brown external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Quadrula mortoni, Specimen #984

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; moderately thick shell; white internal coloring; dark brown external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be long dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Quadrula mortoni, Specimen #898

Description: One preserved mussel specimen including the left valve only. The specimen exhibits a round shape; white internal coloring; dark brown external coloring; no external sculpturing. Collected in the Trinity basin. The specimen measures between 0 - 60 mm in length and was assessed to be very-long dead when collected.
Date: July 18, 1973
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #992

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: August 18, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum
open access

Data report for the Southwest Residential Experiment Station, November 1981

Description: The Southwest Residential Experiment Station (SW RES) is operated in Las Cruces, New Mexico. Physical performance data obtained from the photovoltaic energy systems under test at the SW RES for the month of November 1981, are tabulated.
Date: December 18, 1981
Creator: Lieberman, M.; Hai, O.Y.; Hocking, G. & Whitaker, C.
Partner: UNT Libraries Government Documents Department
open access

Overview of "Travel Ban" Litigation and Recent Developments

Description: This report provides an overview of the series of executive actions (the first two taking the form of executive orders, and the third issued as a presidential proclamation) commonly referred to as the "Travel Ban," which restrict the entry of specified categories of non-U.S. nationals (aliens) into the United States, and the litigation related to those executive actions. It also addresses a fourth and more recent executive action--an executive order issued on October 24, 2017--which announced the general resumption of refugee admissions into the United States (subject to certain restrictions) following the expiration of a temporary suspension on such admissions.
Date: January 18, 2018
Creator: Smith, Hillel R. & Harrington, Ben
Partner: UNT Libraries Government Documents Department
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