Detailed photonuclear cross-section calculations and astrophysical applications (open access)

Detailed photonuclear cross-section calculations and astrophysical applications

We have investigated the role of an isomeric state and its coupling to the ground state (g.s.) via photons and neutron inelastic scattering in a stellar environment by making detailed photonuclear and neutron cross-section calculations for /sup 176/Lu and /sup 210/Bi. In the case of /sup 176/Lu, the g.s. would function as an excellent galactic slow- (s-) process chronometer were it not for the 3.7-h isomer at 123 keV. Our calculations predicted much larger photon cross sections for production of the isomer, as well as a lower threshold, than had been assumed based on earlier measurements. These two factors combine to indicate that an enormous correction, a factor of 10/sup 7/, must be applied to shorten the current estimate of the half-life against photoexcitation of /sup 176/Lu as a function of temperature. This severely limits the use of /sup 176/Lu as a stellar chronometer and indicates a significantly lower temperature at which the two states reach thermal equilibrium. For /sup 210/Bi, our preliminary calculations of the production and destruction of the 3 /times/ 10/sup 6/ y isomeric state by neutrons and photons suggest that the /sup 210/Bi isomer may not be destroyed by photons as rapidly as assumed in certain …
Date: June 15, 1989
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Object Type: Article
System: The UNT Digital Library
Dipole strength functions in the actinide mass region (open access)

Dipole strength functions in the actinide mass region

We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.
Date: July 15, 1987
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
Object Type: Article
System: The UNT Digital Library
Grub-Plow. (open access)

Grub-Plow.

Patent for a grub plow with a better cutter, which can be adjusted to different depths of soil.
Date: August 15, 1911
Creator: Gardner, Eli J. & Odem, David
Object Type: Patent
System: The Portal to Texas History
Recess Appointments Made by President George W. Bush (open access)

Recess Appointments Made by President George W. Bush

None
Date: April 15, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Preliminary Results on the Kinetic Behavior of Water Boiler Reactors (open access)

Preliminary Results on the Kinetic Behavior of Water Boiler Reactors

None
Date: April 15, 1957
Creator: Hetrick, D. L.; Flora, J. W.; Gardner, E. L.; Moskowitz, B. R.; Muller, D. R.; Remley, M. E. et al.
Object Type: Report
System: The UNT Digital Library
Current status of fast-neutron-capture calculations (open access)

Current status of fast-neutron-capture calculations

This work is primarily concerned with the calculation of neutron capture cross sections and capture gamma-ray spectra, in the framework of the Hauser-Feshbach statistical model and for neutrons from the resonance region up to several MeV. An argument is made that, for applied purposes such as constructing evaluated cross-section libraries, nonstatistical capture mechanisms may be completely neglected at low energies and adequately approximated at high energies in a simple way. The use of gamma-ray strength functions to obtain radiation widths is emphasized. Using the reaction /sup 89/Y + n as an example, the problems encountered in trying to construct a case that could be run equivalently on two different nuclear reaction codes are illustrated, and the effects produced by certain parameter variations are discussed.
Date: April 15, 1982
Creator: Gardner, D. G.
Object Type: Article
System: The UNT Digital Library
Report for the NGFA-5 project. (open access)

Report for the NGFA-5 project.

The objective of this project is to provide DHS a comprehensive evaluation of the current genomic technologies including genotyping, TaqMan PCR, multiple locus variable tandem repeat analysis (MLVA), microarray and high-throughput DNA sequencing in the analysis of biothreat agents from complex environmental samples. To effectively compare the sensitivity and specificity of the different genomic technologies, we used SNP TaqMan PCR, MLVA, microarray and high-throughput illumine and 454 sequencing to test various strains from B. anthracis, B. thuringiensis, BioWatch aerosol filter extracts or soil samples that were spiked with B. anthracis, and samples that were previously collected during DHS and EPA environmental release exercises that were known to contain B. thuringiensis spores. The results of all the samples against the various assays are discussed in this report.
Date: November 15, 2011
Creator: Jaing, C; Jackson, P; Thissen, J; Wollard, J; Gardner, S & McLoughlin, K
Object Type: Report
System: The UNT Digital Library
The Effect of Temperature on the Width of a Small-Amplitude, Solitary Wave in a Collision-Free Plasma (open access)

The Effect of Temperature on the Width of a Small-Amplitude, Solitary Wave in a Collision-Free Plasma

"Adlam and Allen and Davis, Lust, and Schluter have studied nonlinear plane-waves, propagating normal to the magnetic field, in a cold plasma. One solution of particular interest is a solitary wave, or single pulse. We present a method for solving the analogous problem for a plasma with finite temperature, in the limiting case where the amplitude of the wave is small and where, consequently, the width of the waver is very large."
Date: March 15, 1961
Creator: Gardner, Clifford S.
Object Type: Report
System: The UNT Digital Library
A review of plutonium environmental data with a bibliography for use in risk assessments (open access)

A review of plutonium environmental data with a bibliography for use in risk assessments

Plutonium fueled radioisotopic heat sources find space, terrestrial, and undersea applications to generate electrical power. Such systems under postulated accident conditions could release radioactivity into the environment resulting in risks to the general population in the form of radiological doses and associated health effects. The evaluation of the radiological impact of postulated scenarios involving releases of activity into the environment includes identification of postulated accident release modes, including the probability of release and the release location; source term definition, including the activity of each radionuclide released and the corresponding chemical form and particle size distribution; analysis of the environmental behavior of the released radioactivity to determine the concentrations in environmental media (air, soil, and water) as a function of time; and analysis of the interaction between the environmental concentrations and man, leading to ingestion, inhalation, and external doses through each environmental exposure pathway. 443 refs., 2 figs., 4 tabs.
Date: June 15, 1983
Creator: Bartram, B.W. & Wilkinson, M.J.
Object Type: Report
System: The UNT Digital Library
Advanced, Graphite-Matrix, Dispersion-Type Fuel Systems And Research on Graphite. Quarterly Progress Report for the Period Ending February 14, 1965 (open access)

Advanced, Graphite-Matrix, Dispersion-Type Fuel Systems And Research on Graphite. Quarterly Progress Report for the Period Ending February 14, 1965

None
Date: February 15, 1965
Creator: Bokros, J. C.; Goeddel, W. V.; Lonsdale, H. K.; Price, R. J.; White, J. L. & Zumwalt, L. R.
Object Type: Report
System: The UNT Digital Library
Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams (open access)

Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams

None
Date: September 15, 2011
Creator: Singhal, P.; Rodriguez, J. N.; Small, W., IV; Eagleaston, S.; De Water, J. V.; Maitland, D. J. et al.
Object Type: Article
System: The UNT Digital Library
Limit of detection of Bacillus anthracis in complex soil and air samples using next-generation sequencing (open access)

Limit of detection of Bacillus anthracis in complex soil and air samples using next-generation sequencing

None
Date: March 15, 2012
Creator: Be, Nicholas A.; Thissen, James B.; Gardner, Shea; McLoughlin, Kevin; Fofanov, Viacheslav; Koshinsky, Heather et al.
Object Type: Article
System: The UNT Digital Library
Rake. (open access)

Rake.

Patent for a rake with curved ends and multiple teeth that hold the material and keep it from going to the sides.
Date: August 15, 1916
Creator: Green, Ella M.
Object Type: Patent
System: The Portal to Texas History
Plutonium Metallurgy Operation quarterly progress report, July--September 1962 (open access)

Plutonium Metallurgy Operation quarterly progress report, July--September 1962

Progress reports are presented for the following tasks: physical and mechanical metallurgy; plutonium fuels development; and special fabrication of plutonium and other radioactive materials.
Date: October 15, 1962
Creator: Wick, O. J.; Nelson, T. C.; Stewart, R. W. & Thomas, I. D.
Object Type: Report
System: The UNT Digital Library
A quasilinear model for solute transport under unsaturated flow (open access)

A quasilinear model for solute transport under unsaturated flow

We developed an analytical solution for solute transport under steady-state, two-dimensional, unsaturated flow and transport conditions for the investigation of high-level radioactive waste disposal. The two-dimensional, unsaturated flow problem is treated using the quasilinear flow method for a system with homogeneous material properties. Dispersion is modeled as isotropic and is proportional to the effective hydraulic conductivity. This leads to a quasilinear form for the transport problem in terms of a scalar potential that is analogous to the Kirchhoff potential for quasilinear flow. The solutions for both flow and transport scalar potentials take the form of Fourier series. The particular solution given here is for two sources of flow, with one source containing a dissolved solute. The solution method may easily be extended, however, for any combination of flow and solute sources under steady-state conditions. The analytical results for multidimensional solute transport problems, which previously could only be solved numerically, also offer an additional way to benchmark numerical solutions. An analytical solution for two-dimensional, steady-state solute transport under unsaturated flow conditions is presented. A specific case with two sources is solved but may be generalized to any combination of sources. The analytical results complement numerical solutions, which were previously required to …
Date: May 15, 2009
Creator: Houseworth, J.E. & Leem, J.
Object Type: Article
System: The UNT Digital Library
Ninth Workshop on Geothermal Reservoir Engineering: Proceedings (open access)

Ninth Workshop on Geothermal Reservoir Engineering: Proceedings

The attendance at the Workshop was similar to last year's with 123 registered participants of which 22 represented 8 foreign countries. A record number of technical papers (about 60) were submitted for presentation at the Workshop. The Program Committee, therefore, decided to have several parallel sessions to accommodate most of the papers. This format proved unpopular and will not be repeated. Many of the participants felt that the Workshop lost some of its unique qualities by having parallel sessions. The Workshop has always been held near the middle of December during examination week at Stanford. This timing was reviewed in an open discussion at the Workshop. The Program Committee subsequently decided to move the Workshop to January. The Tenth Workshop will be held on January 22-24, 1985. The theme of the Workshop this year was ''field developments worldwide''. The Program Committee addressed this theme by encouraging participants to submit field development papers, and by inviting several international authorities to give presentations at the Workshop. Field developments in at least twelve countries were reported: China, El Salvador, France, Greece, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, the Philippines, and the United States. There were 58 technical presentations at the Workshop, of …
Date: December 15, 1983
Creator: Ramey, H. J., Jr.; Kruger, P.; Miller, F.G.; Horne, R.N.; Brigham, W.E. & Gudmundsson, J.S.
Object Type: Article
System: The UNT Digital Library
Combined Torch and Gas Burner Key. (open access)

Combined Torch and Gas Burner Key.

Patent for a new and improved combined torch and gas-burner key. This design "relates to a device for lighting gas-burners and operating the cock of the gas-burner, and has for its object to provide a combined torch and key by means of which the gas may be lighted without the flame of the torch coming in contact with the globe surrounding the burner and the cock of the gas-burner readily taken hold of and operated" (lines 8-15).
Date: October 15, 1889
Creator: Lindsay, George Washington
Object Type: Patent
System: The Portal to Texas History
Differential Distributions of Neutrons in Inelastic π$sup -$P Interactions at 374, 417, and 454 Mev (open access)

Differential Distributions of Neutrons in Inelastic π$sup -$P Interactions at 374, 417, and 454 Mev

The inelastic interactions of negative pi mesons with protons at 374, 417, and 454 Mev incident pi kinetic energy are studied by measuring the differential distributions of finalstate neutrons. The pi source is an internal target of the Berkeley 184-inch synchrocyclotron. A magnetic beamtransport system momentum-anaiyzes and focuses the pi beam at a liquid hydrogen target located in an adjacent shielded experimental area. The time-of- flight distribution of neutral particles is measured at various laboratorysystem angles between 10 and 65 deg. Neutral particles are detected by observing the charged products of their interactions in plastic scintillator. The time-of- flight information is determined electronically by time-to-height conversion and pulse-height analysis. The time resolution of the total system is 1.0 nsec. Detected neutral particles accompanied by charged particles are separated by the electronic system from those not accompanied by charged particles. Analysis presuming the principal inelastic reactions to be pi /sup -/p yields pi /sup +/ pi /sup -/n and pi /sup -/p yields pi /sup 0/ pi /sup 0/n separates the time-of-flight spectra into gamma rays, neutrons from the reaction pi /sup -/p yields pi /sup 0/n, and inelastic neutrons. Calculated values of the neutron- detection efficiency are used in the …
Date: November 15, 1962
Creator: Kurz, R. J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Study of the Technique of Utilizing a Microwave Fabry--Perot Resonator to Obtain Spatial Electron Density Distributions in a Minimum-B Plasma (open access)

Study of the Technique of Utilizing a Microwave Fabry--Perot Resonator to Obtain Spatial Electron Density Distributions in a Minimum-B Plasma

None
Date: May 15, 1973
Creator: Struve, K. W.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
AC Loss Measurements with a Cryocooled Sample (open access)

AC Loss Measurements with a Cryocooled Sample

A new cryostat cooled by a closed-cycle Cryomech GB-37 cryocooler for superconductor measurements at temperatures down to 20 K is described. The sample is conductively coupled to the cold stage so as to minimize vibration and thermal stresses. AC losses have been measured calorimetrically in several HTSC coils that have been wound to simulate sub-scale transformer winding pairs. Stable temperatures down to 20 K were reached on these coils, allowing measurements at practical levels of ac current and I{sub c}. By using short ac current pulses, losses on individual turns could be resolved. Results are reported mainly to showcase the apparatus, measurement procedure and analytical approach.
Date: February 15, 2001
Creator: Schwenterly, S.W.
Object Type: Article
System: The UNT Digital Library
Measurement of the Bespalov-Talanov gain spectrum in a dispersive medium with large n{sub 2} (open access)

Measurement of the Bespalov-Talanov gain spectrum in a dispersive medium with large n{sub 2}

Conditions which seed the self focussing of high-power broadband laser beams are determined by examining growth rates for plane-wave perturbations on a strong pump field as a function of frequency and angle. Measurements verifying predictions of growth based on the linearized stability analysis of Bespalov and Talanov extended to broadband fields are reported.
Date: June 15, 1995
Creator: Wegner, P. J.; Feit, M. D.; Fleck, J. A., Jr. & Eimerl, D.
Object Type: Article
System: The UNT Digital Library
Low Odor, High Yield Kraft Pulping (open access)

Low Odor, High Yield Kraft Pulping

In laboratory cooks pure oxygen was profiled into the circulation line of a batch digester during two periods of the cooking cycle: The first injection occurred during the heating steps for the purpose of in-situ generation of polysulfide. This chip treatment was studied to explore stabilization against alkaline induced carbohydrate peeling and to increase pulp yield. Under optimum conditions small amounts of polysulfide were produced with yield increase of about 0.5% These increases fell below earlier reports suggesting that unknown differences in liquor composition may influence the relative amounts of polysulfide and thiosulfate generated during the oxidation. Consequently, further studies are required to understand the factors that influence the ratios of those two sulfur species.
Date: December 15, 2000
Creator: McKean, W. T.
Object Type: Report
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

Most prokaryotes of interest to DOE are poorly understood. Even when full genomic sequences are available, the function of only a small number of gene products are clear. The critical question is how to best infer the most probable network architectures in cells that are poorly characterized. The project goal is to create a computational hypothesis testing (CHT) framework that combines large-scale dynamical simulation, a database of bioinformatics-derived probable interactions, and numerical parallel architecture data-fitting routines to explore many “what if ?” hypotheses about the functions of genes and proteins within pathways and their downstream effects on molecular concentration profiles and corresponding phenotypes. From this framework we expect to infer signal transduction pathways and gene expression networks in prokaryotes. Detailed mechanistic models of E. Coli have been developed that directly incorporate DNA sequence information. The CHT framework is implemented in the NIEngine network inference software. NIEngine has been applied to recover gene regulatory networks in E. coli to assess performance. Application to Shewanel la oneidensi and other organism of interest DOE will be conducted in partnership with Jim Collin's Lab at Boston University and other academic partners. The CHT framework has also found broad application in the automated learning of …
Date: October 15, 2008
Creator: Church, Bruce W
Object Type: Report
System: The UNT Digital Library
Design and Installation of a High Precision Temperature and Intimate Contact Monitor for Experimental Vacuum Chucks (open access)

Design and Installation of a High Precision Temperature and Intimate Contact Monitor for Experimental Vacuum Chucks

Describes the design criteria, design details, and final installation of a high precision temperature and intimate contact monitor.
Date: May 15, 1958
Creator: Morrow, G. W.
Object Type: Report
System: The UNT Digital Library