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Noncanonical Hamiltonian methods in plasma dynamics

Description: A Hamiltonian approach to plasma dynamics has numerous advantages over equivalent formulations which ignore the underlying Hamiltonian structure. In addition to achieving a deeper understanding of processes, Hamiltonian methods yield concise expressions (such as the Kubo form for linear susceptibility), greatly shorten the length of calculations, expose relationships (such as between the ponderomotive Hamiltonian and the linear susceptibility), determine invariants in terms of symmetry operatio… more
Date: November 1, 1981
Creator: Kaufman, A. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of additional fission sources or scattering sources to model inward axial leakages in fast-reactor analysis

Description: When calculations of flux are done in less than three dimensions, bucklings are normally used to model leakages (flows) in the dimensions for which the flux is not calculated. If the net leakage for a given energy group is outward (positive), the buckling is positive, and buckling methods work well. However, if the new leakage for a given energy group is inward (negative), the buckling is negative and can lead to numerical instabilities (oscillations in the iterative flux calculation). This rep… more
Date: October 1, 1981
Creator: Grimm, K. N. & Meneghetti, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ozone mass transfer and kinetics experiments

Description: Experiments were conducted at the Hanford Site to determine the most efficient pH and temperature levels for the destruction of complexants in Hanford high-level defense waste. These complexants enhance migration of radionuclides in the soil and inhibit the growth of crystals in the evaporator-crystallizer. Ozone mass transfer and kinetics tests have been outlined for the determination of critical mass transfer and kinetics parameters of the ozone-complexant reaction.
Date: December 1981
Creator: Bollyky, L. Joseph & Beary, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Particle size distribution of airborne plutonium near a chemical separations facility

Description: Particulate matter containing Pu-238 and Pu-239,240 emitted from a stack at the Savannah River Plant was collected and fractionated by size with cascade impactors. Two impactor measurements were made at a distance of 200 meters from the H-Area stack and a third was at a distance of 420 meters. Annual collections were made for three years. The Pu-238 and Pu 239,240 concentrations were determined for each of the size fractions. The fractions collected at 200 m from the 62 m stack showed a biphasi… more
Date: December 1, 1981
Creator: Gay, D. D. & Watts, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental method for reactor-noise measurements of effective beta. [LMFBR]

Description: A variance-to-mean noise technique, modified to eliminate systematic errors from drifting of reactor power, has been used to infer integral values of effective beta for uranium and plutonium fueled fast reactor modk-ups. The measurement technique, including corrections for a finite detector-electrometer time response, is described together with preliminary beta measurement results.
Date: September 1, 1981
Creator: Bennett, E.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of low-energy-electron-capture collisions (H/sub 0/ + c/sup n+/) on the particle and energy balance of tokamak plasmas

Description: To illustrate the way in which atomic data provides enlightenment in the search for understandable (and thus extrapolable) confinement models, we restrict our scope to electron capture collisions involving H/sub 0/ and multiply-charged ions. Many such foreign (impurity) multiply-charged ion species are found in plasma discharges, as a result of gas recycling and damage to the surrounding surfaces by energetic plasma particles. Typical low-Z ions are carbon and oxygen; the major constituents of … more
Date: January 1, 1981
Creator: Hogan, J. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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COROPT heterogeneous flux model

Description: The PHYSICS module of COROPT calculates the power and flux distributions, power fractions, required fissile enrichment, and fuel mass balances. Sufficiently accurate data are clearly necessary for the results of the thermal hydraulic and fuel pin and assembly performance analysis to be acceptable. The smooth flux and power distribution model developed for the homogeneous core COROPT application has been shown to be accurate for homogeneous cores in the range of interest. However, this model and… more
Date: September 1, 1981
Creator: Bailey, H.S. & Alexander, C.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Los Alamos benchmarks: calculations based on ENDF/B-V data

Description: The new and revised benchmark specifications for nine Los Alamos National Laboratory critical assemblies are used to compute the entire set of parameters that were measured in the experiments. A comparison between the computed and experimental values provides a measure of the adequacy of the specifications, cross sections, and physics codes used in the calculations.
Date: November 1, 1981
Creator: Kidman, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Review of the neutron capture process in fission reactors

Description: The importance of the neutron capture process and the status of the more important cross section data are reviewed. The capture in fertile and fissile nuclei is considered. For thermal reactors the thermal to epithermal capture ratio for /sup 238/U and /sup 232/Th remains a problem though some improvements were made with more recent measurements. The capture cross section of /sup 238/U in the fast energy range remains quite uncertain and a long standing discrepancy for the calculated versus exp… more
Date: July 1, 1981
Creator: Poenitz, W.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Specifications for the Large Core Code Evaluation Working Group Benchmark Problem Four. [LMFBR]

Description: Benchmark studies have been carried out by the members of the Large Core Code Evaluation Working Group (LCCEWG) as part of a broad effort to systematically evaluate the important steps in the reactor design and analysis process for large fast breeder reactors. The specific objectives of the LCCEWG benchmark studies have been: to quantify the accuracy and efficiency of current neutronics methods for large cores; to identify neutronic design problems unique to large breeder reactors; to identify … more
Date: September 1, 1981
Creator: Cowan, C.L. & Protsik, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Use of Additional Fission Sources or Scattering Sources to Model Inward Axial Leakages in Fast-Reactor Analysis

Description: When calculations of flux are done in less than three dimensions, bucklings are normally used to model leakages (flows) in the dimensions for which the flux is not calculated. If the net leakage for a given energy group is outward (positive), the buckling is positive, and buckling methods work well. However, if the new leakage for a given energy group is inward (negative), the buckling is negative and can lead to numerical instabilities (oscillations in the iterative flux calculation). This rep… more
Date: October 1981
Creator: Grimm, K. N. & Meneghetti, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

An Experimental Method for Reactor-Noise Measurements of Effective Beta

Description: A variance-to-mean noise technique, modified to eliminate systematic errors from drifting of reactor power, has been used to infer integral values of effective beta for uranium and plutonium fueled fast reactor modk-ups. The measurement technique, including corrections for a finite detector-electrometer time response, is described together with preliminary beta measurement results.
Date: September 1981
Creator: Bennett, E. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Curvature on Asymmetric Steady States in Catalyst Particles

Description: The effects of curvature on steady states of chemical catalytic reactions are investigated by studying the cases of the catalytic particle being a spherical or cylindrical shell. Existence and stability of solutions are studied. It is shown that the solutions converge to the solutions for the catalytic slab when the curvature goes to 0 in each case.
Date: February 1981
Creator: Lucier, Bradley J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Environmental effects of a tritium release from the Savannah River Plant

Description: On March 27, 1981, a small amount of tritiated water was inadvertently released from the tritium-processing facility during a routine maintenance operation. This report describes the environmental effects of this release both on the SRP site and offsite. Also, the operation of the WIND (Wind Information and Display) emergency response system during the incident is discussed, and the predicted and diagnosed behavior of the tritium plume is compared with tritium concentrations deduced from air, v… more
Date: November 1, 1981
Creator: Garrett, A. J.; Wilhite, E. L. & Buckner, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biomedical research with cyclotron produced radionuclides. Progress report, February 1, 1981-December 31, 1981

Description: Progress is reported in the following areas: evaluation of chemotherapeutic regimens in solid tumors using /sup 13/N-labelled amino acids; organ imaging with /sup 13/N-labelled L-amino acids; imaging with /sup 111/In-labelled-autologous platelets; synthesis and biological studies of /sup 111/In-labelled ammonia and L-amino acids; synthesis and evaluation for pancreatic imaging of /sup 11/C-labelled amino acides; radioisotope monitoring of myocardiol function; synthesis of /sup 11/C-labelled pre… more
Date: September 1, 1981
Creator: Laughlin, J.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Reactions of ions with atomic and molecular free radicals. Progress report, May 1, 1981-April 30, 1982. [Summaries of research activities at the University of Minnesota]

Description: Analysis and interpretation of the data on the reactions of H/sub 2//sup +/ with N, C, O and F were completed, along with some supplementary investigations of collision-induced dissociation of the exotic species NH/sub 3//sup 2 +/ and CS/sub 2//sup 3 +/. As the focus of this project shifts to other systems and phenomena, construction of a new crossed, pulsed molecular beam apparatus has been begun, and is now about 75% complete. The new instrument will permit state-resolved studies of energy tr… more
Date: November 1, 1981
Creator: Gentry, W.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Projections of transport scaling laws for small toroidal reactors

Description: Transport in present day Spheromaks is dominated by impurity radiation. Fortunately, this is largely from oxygen and carbon, not metal vapor from the walls of the vessel on plasma guns and it is expected this loss can be eliminated by improved technique. The formation and gross MHD stability properties of these plasmas are quite well understood and so the reactor predictions depend on estimates of the energy loss rates from the plasma. In the absence of significant experimental data one is driv… more
Date: November 16, 1981
Creator: McNamara, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of calculations with neutron dosimetry measurements performed at the Oak Ridge Poolside Facility

Description: The Oak Ridge Poolside Facility (PSF), like the Pool Critical Assembly (PCA), is used for benchmark dosimetry measurements which can serve to validate the transport methods used in calculating the high-energy neutron fluences (> 0.1 MeV) in LWR pressure vessels required to estimate the neutron damage to the pressure vessels in the form of embrittlement. The PSF consists of an arrangement of two water gaps of 4 and 12 cm thickness separated by a simulated thermal shield and followed by a simulat… more
Date: January 1, 1981
Creator: Maerker, R.E. & Williams, M.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Film Analysis Systems and Applications

Description: The different components that can be used in modern film analysis systems are reviewed. TV camera and charge-coupled device sensors coupled to computers provide low cost systems for applications such as those described. The autoradiography (ARG) method provides an important tool for medical research and is especially useful for the development of new radiopharmaceutical compounds. Biodistribution information is needed for estimation of radiation dose, and for interpretation of the significance … more
Date: January 1, 1981
Creator: Yonekura, Y. & Brill, A. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiated energy and impurity density changes during intensive hydrogen influx in the PLT tokamak

Description: During a discharge a puff of hydrogen is admitted, sufficient to more than triple the plasma density, and the resulting changes in various plasma parameters are determined. The absolute densities of various wall and limiter (carbon) materials are found to decrease by a substantial fraction, probably as a result of lowered peripheral temperature. The radiation pattern deduced from spectroscopically determined plasma composition is in good quantitative agreement with direct bolometric measurement… more
Date: December 1, 1981
Creator: Hinnov, E.; Hosea, J.; Hsuan, H.; Jobes, F.; Meservey, E.; Schmidt, G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CARDIOGRAMA: a stochastic, semi-empirical methodology for power-reactor surveillance and diagnostics

Description: The utilization of stochastic methods (reactor noise) for power reactor diagnostics and surveillance applications is by now a relatively well-established technique. In this technique, the power spectral density (PSD) of the fluctuations of a specified state variable is often used to define the reactor's signature at a given configuration. The purpose of the present work is to address the problem of handling efficiently the substantial amount of information involved in the application of reactor… more
Date: January 1, 1981
Creator: March-Leuba, J.A.; deSaussure, G. & Perez, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Monte Carlo model of neutral-particle transport in diverted plasmas

Description: The transport of neutral atoms and molecules in the edge and divertor regions of fusion experiments has been calculated using Monte-Carlo techniques. The deuterium, tritium, and helium atoms are produced by recombination in the plasma and at the walls. The relevant collision processes of charge exchange, ionization, and dissociation between the neutrals and the flowing plasma electrons and ions are included, along with wall reflection models. General two-dimensional wall and plasma geometries a… more
Date: November 1, 1981
Creator: Heifetz, D.; Post, D.; Petravic, M.; Weisheit, J. & Bateman, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interaction of manganese(II) with the surface of calcite in dilute solutions and seawater

Description: The interaction of Mn/sup 2 +/ with the surface of calcite in aqueous solutions is complex. In dilute solutions the Mn/sup 2 +/ is rapidly adsorbed, MnCO/sub 3/ nucleates on the calcite surface and then grows by a first order reaction with respect to the initial Mn/sup 2 +/ concentration. At higher ionic strengths, in NaCl solutions, the rate of these processes is slower, but the same general pattern persists. In solutions containing Mg/sup 2 +/, at the concentration of seawater and in seawater… more
Date: July 1, 1981
Creator: Franklin, M. L. & Morse, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of the lumped fission-product uncertainty in CRBR

Description: An approximation made in most fast reactor analyses is to utilize a single lumped fission product (FP) cross-section set to represent the total effect of the approximately 800 possible fission product nuclides in a depleted reactor model. Recent investigations have analyzed several aspects of this one-lump approximation (burnup dependence, comparison with a two-lump model, etc.), but little has been done in addressing the quality, or uncertainty, in the basic cross-section data utilized in any … more
Date: January 1, 1981
Creator: White, J.R. & Schenter, R.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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