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Tellurium interference in /sup 129/I activation analysis

Description: Measurement of /sup 129/I at low levels is required for effluent control, environmental assessment and tracer studies in the natural environment. Low level /sup 129/I analysis has also been used for measurement of natural-fission-produced /sup 129/I in minerals and ores as well as meteorites. The most sensitive method for /sup 129/I measurements is neutron activation analysis of iodine separated from a suitable sample. Minimum sample processing prior to neutron activation is desirable in order … more
Date: September 20, 1979
Creator: Kaye, J. H.; Brauer, F. P. & Strebin, Jr., R. S.
Partner: UNT Libraries Government Documents Department
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Computed and experimental interactions between eddy structure and dispersed particles in developing free shear layers

Description: We are investigating the interactive process between turbulent flow and dispersed phase particles. We are focusing on the mechanisms that appear to result in a reduction of local turbulent intensity and a corresponding reduction in wall heat transfer and subsequent wall erosion in turbulent solid propellant combustion flow. We apply computational simulations and physical experiments specialized to a developing free shear layer over a rearward facing step and over a parallel splitter plate. The … more
Date: May 20, 1982
Creator: Buckingham, A. C.; Siekhaus, W. J.; Keller, J. O.; Ellzey, J.; Hubbard, G. & Daily, J. W.
Partner: UNT Libraries Government Documents Department
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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

Description: An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Partner: UNT Libraries Government Documents Department
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Fusion breeder

Description: The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be mad… more
Date: April 20, 1982
Creator: Moir, Ralph W.
Partner: UNT Libraries Government Documents Department
open access

Assessment of the response of spent fuel transports to malevolent acts

Description: This paper describes the results of a program conducted at Sandia National Laboratories (SNL) for the US Department of Energy to provide an experimental data base for more accurately assessing the radiological consequences from a hypothetical sabotage attack on a spent fuel shipping cask. The primary objectives of the program were limited to: (1) evaluating the effectiveness of selected high explosive devices (HED) in breaching full-size spent fuel casks, (2) quantifying and characterizing rele… more
Date: December 20, 1983
Creator: Sandoval, R.P.
Partner: UNT Libraries Government Documents Department
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Review of single transient oscillographic recorders with gigahertz bandwidth

Description: In laser driven inertial confinement fusion research, at Livermore, we are diagnosing many phenomena that occur in a time frame that exceeds the capabilities of even the most advanced, present day oscillographic recording instruments. Many of the by-products of the interaction between the laser beam and fuel pellet are monitored to determine the specifics of the fusion process. By the use of appropriate detectors, we convert the information contained in the radiated by-products to electrical si… more
Date: October 20, 1982
Creator: Campbell, D.E.
Partner: UNT Libraries Government Documents Department
open access

Remote servicing features of two new mirror fusion reactors

Description: Several general approaches to remote servicing are briefly described for the LLL Field Reversed Mirror and Tandem Mirror Fusion reactors. Remote servicing system design considerations for the blanket module are briefly discussed. (RME)
Date: April 20, 1977
Creator: Neef, W.S. Jr.
Partner: UNT Libraries Government Documents Department
open access

The MTX (Microwave Tokamak Experiment) data acquisition system

Description: The diagnostic data from the MTX experiment is acquired and processed by an expandable, distributed, multivendor computer network. The system blends a variety of software into a coordinated, unified, and highly flexible design. Using modular software design techniques, we created a system stressing distributed processing, portability, and transparent data access. In our approach to modularity, we standardized communication interfaces between modules and separated generic tasks from machine and … more
Date: September 20, 1989
Creator: Butner, D. N.; Drlik, M.; Brown, M. D.; Casper, T. A.; Meyer, W. H. & Moller, J. M.
Partner: UNT Libraries Government Documents Department
open access

Materials testing using laser energy deposition

Description: A convenient method for determining the elastic constants of materials has been devised using the energy from a Q-switched neodymium-glass laser. Stress waves are induced in materials having circular rod or rectangular bar geometries by the absorption of energy from the laser. The wave transit times through the material are recorded with a piezoelectric transducer. Both dilatation and shear wave velocities are determined in a single test using an ultrasonic technique and these velocities are us… more
Date: December 20, 1977
Creator: Wilcox, W.W. & Calder, C.A.
Partner: UNT Libraries Government Documents Department
open access

Monopole search using an accelerator detector

Description: A neutrino detector at the Brookhaven AGS has been used to investigate the feasibility of using an already constructed apparatus for GUT monopole searches. A flux limit (90%CL) of 5.2 x 10/sup -12/ cm/sup -2/ sec/sup -1/ str/sup -1/ was found. The limitations of such an approach are discussed.
Date: December 20, 1983
Creator: Ahrenes, L.A.; Aronson, S.H.; Connolly, P.L.; Erickson, T.E.; Gibbard, B.G.; Montag, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Electron cyclotron resonant heating (ECRH) diagnostic system on TMX

Description: The ECRH diagnostics system monitors the net power delivered to the plasma by four 200-kW gyrotron oscillators, the frequency of each gyrotron, and some operating parameters of the gyrotron power supply system. The combination CAMAC- and GPIB-based data acquisition system is under desktop computer control that provides the capability for data conversion and display. The data acquisition system is also interfaced to the main computer system that acquires and archives the data.
Date: October 20, 1981
Creator: Coffield, F.E. & Griffin, D.H.
Partner: UNT Libraries Government Documents Department
open access

Radiation interactions for tomography. Revision 1

Description: There are new requirements emerging in the field of tomography: the need for spatial resolution in the micrometre range, atomic species specificity, and quantitative density discrimination.
Date: May 20, 1985
Creator: Zolnay, A.S.
Partner: UNT Libraries Government Documents Department
open access

Position and profile of a multiampere proton beam

Description: The spacial profile of a bunched or unbunched proton beam may be found by using a highly collimated molecular beam of N/sub 2/. A certain fraction of the molecular N/sub 2/ will be ionized as it crosses the proton beam. By measuring the N/sub 2//sup +/ current as a function of theta the cross section of the beam is directly obtained. As an example, a 10 A proton beam of diameter 1 mm is considered.
Date: October 20, 1977
Creator: Edwards, D. Jr.
Partner: UNT Libraries Government Documents Department
open access

Why search for double beta decay

Description: Searching for neutrinoless double beta decay is the only known practical method for trying to determine whether neutrinos are their own antiparticles. The theoretical motivation for supposing that they may indeed be their own antiparticles is described. The reason that it is so difficult to ascertain experimentally whether they are or are not is explained, as is the special sensitivity of neutrinoless double beta decay. The potential implications of the observation of this reaction for neutrino… more
Date: April 20, 1988
Creator: Kayser, B.
Partner: UNT Libraries Government Documents Department
open access

Laser produced plasma soft x-ray generation

Description: The efficiency of soft x-ray production from laser-irradiated plasmas is simulated for two different spectral regions. These two regions, 14{Angstrom} {plus minus} 15% and 130{Angstrom} {plus minus} 1%, were chosen for proximity mask or point-projection technological applications. Relatively large conversion efficiencies were obtained from irradiation of a stainless steel target using the conditions suggested by recent Hampshire Instruments' experiments for proximity masking. Pulse-width and la… more
Date: May 20, 1991
Creator: Cerjan, C. & Rosen, M.D.
Partner: UNT Libraries Government Documents Department
open access

Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF)

Description: The Mirror Fusion Test Facility (MFTF) may be upgraded by extending the time of plasma sustenance in an approach to steady-state operation and/or by increasing the neutral-beam injection energy. Some parameter bounds for these upgrades are discussed as they relate to a definition of the required neutral-beam development.
Date: December 20, 1977
Creator: Damm, C. C.; Coensgen, F. H.; Devoto, R. S.; Molvik, A. W.; Porter, G. D.; Shearer, J. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Elementary reaction rate measurements at high temperatures by tunable-laser flash-absorption

Description: The major objective of this program is to measure thermal rate coefficients and branching ratios of elementary reactions. To perform these measurements, we have constructed an ultrahigh-purity shock tube to generate temperatures between 1000 and 5500 K. The tunable-laser flash-absorption technique is used to measure the rate of change of the concentration of species which absorb below 50,000 cm{sup {minus}1} e.g.: OH, CH, and CH{sub 3}. This technique is being extended into the vacuum-ultraviol… more
Date: March 20, 1992
Creator: Hessler, J.P.
Partner: UNT Libraries Government Documents Department
open access

Anomalous isotopic composition of cosmic rays

Description: Recent measurements of nonsolar isotopic patterns for the elements neon and (perhaps) magnesium in cosmic rays are interpreted within current models of stellar nucleosynthesis. One possible explanation is that the stars currently responsible for cosmic-ray synthesis in the Galaxy are typically super-metal-rich by a factor of two to three. Other possibilities include the selective acceleration of certain zones or masses of supernovas or the enhancement of /sup 22/Ne in the interstellar medium by… more
Date: June 20, 1980
Creator: Woosley, S. E. & Weaver, T. A.
Partner: UNT Libraries Government Documents Department
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Preliminary Assessment of Microbiome Changes Following Blood-Feeding and Survivorship in the Amblyomma americanum Nymph-to-Adult Transition using Semiconductor Sequencing

Description: Article on a preliminary assessment of microbiome changes following blood-feeding and survivorship in the Amblyomma americanum nymph-to-adult transition using semiconductor sequencing.
Date: June 20, 2013
Creator: Menchaca, Arturo C.; Visi, David K.; Strey, Otto F.; Teel, Pete D.; Kalinowski, Kevin E.; Allen, Michael S. et al.
Partner: UNT College of Arts and Sciences
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Report from the polarization group of the Fermilab injector workshop

Description: The group considered physics, accelerator, and polarized source issues. Most of the physics study was concerned with what significant and unique experiments could be done if polarized protons could be accelerated in the main injector and eventually in the Tevatron. 12 refs., 4 figs.
Date: July 20, 1989
Creator: Berger, E.; Glass, G.; Imai, K.; Jones, L.; Lin, A.M.T.; Mane, S.R. et al.
Partner: UNT Libraries Government Documents Department
open access

Fusion breeder blanket nucleonics

Description: Refined nuclear analysis, including the treatment of resonance and spatial self-shielding, coupled with an optimization procedure, has resulted in improved performance estimates for two conceptual fission-suppressed blankets. Net specific breeding in these two blankets maximized at 0.024 and 0.023 U-233 atoms/MeV, which is about an order of magnitude higher than in fission breeders.
Date: June 20, 1986
Creator: Lee, J. D.
Partner: UNT Libraries Government Documents Department
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Resonance localization in tokamaks excited with ICRF waves

Description: Advanced wave models used to evaluate ICRH in tokamaks typically use warm plasma theory and allow inhomogeneity in one dimension. The majority of these calculations neglect the fact that gyrocenters experience the inhomogeneity via their motion parallel to the magnetic field. The non-local effects of rotational transform and toroidicity can play a significant role in both the propagation and the absorption physics. In strongly driven systems, wave damping can distort the particle distribution f… more
Date: June 20, 1985
Creator: Kerbel, G. D. & McCoy, M. G.
Partner: UNT Libraries Government Documents Department
open access

Photocathode transfer and storage techniques using alkali vapor feedback control

Description: Photocathodes of quantum efficiency above 1% at the doubled YAG frequency of 532 nM are very sensitive to the local vacuum environment. These cathodes must have a band gap of less than 2.3 eV, and a work function that is also on the order of {approximately}2 volts or less. As such, these surfaces are very reactive as they provide many surface states for the residual gases that have positive electron affinities such as oxygen and omnipotent water. Attendant to this problem is that the optimal op… more
Date: December 20, 1991
Creator: Springer, R.W. & Cameron, B.J.
Partner: UNT Libraries Government Documents Department
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