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Dose-rate conversion factors for external exposure to photons and electrons

Description: Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sou… more
Date: August 1, 1981
Creator: Kocher, David C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Material Considerations in the Design of a Bulk Shield for the Fusion Engineering Device

Description: The FED bulk shield provides protection from high-energy neutrons and gamma rays and removes nuclear heat generated. Bulk shield optimization calculations were conducted using the Los Alamos ONEDANT discrete ordinates and the General Atomic PATH point kernel codes. Six candidate steel alloys were considered.
Date: January 1, 1981
Creator: Kirchner, J. & Engholm, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vacuum system problems of EBT: a steady-state fusion experiment

Description: Many of the vacuum problems faced by EBT will soon be shared by other plasma devices as high-power microwave systems and long pulse lengths become more common. The solutions used on EBT (such as the raised lip with elastomer seal) are not unique; however, experience has shown that microwave-compatible designs must be carefully thought out. All details of the vacuum must be carefully thought out. All details of the vacuum must be carefully screened in advance to insure that microwaves do not lea… more
Date: January 1, 1981
Creator: Livesey, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ion-beam depth-profiling studies of leached glasses

Description: Ion-beam depth-profiling was carried out on three different glasses leached (or hydrated) in deionized water using /sup 1/H(/sup 19/F,..cap alpha gamma..)/sup 16/O nuclear reaction, secondary ion mass spectrometry (SIMS) and sputter-induced photon spectrometry (SIPS) techniques. The depth-profiles show an interdiffusion mechanism in which the sodium ions in the glass are depleted and replaced by hydrogen (H/sup +/) or hydronium (H/sub 3/O/sup +/) ions from the solution. The leaching behavior do… more
Date: January 1, 1981
Creator: Houser, C. A.; Tsong, I. S. T.; White, W. B.; Wintenberg, A. L.; Miller, P. D. & Moak, C. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Size distribution of autotrophy and microheterotrophy in reservoirs: implications for foodweb structure

Description: Particle size is a primary determinant of resources available to consumers and of the efficiency of energy transfer through planktonic food chains. Dual radioisotopic labeling (with /sup 14/C-bicarbonate and /sup 3/H-acetate) and size fractionation of naturally-occurring phytoplankton-bacterioplankton assemblages were employed to examine the particle size distributions of planktonic autotrophy and microheterotrophy in four limnologically-dissimilar US reservoirs (Lake Mead, Arizona-Nevada, olig… more
Date: January 1, 1981
Creator: Kimmel, B. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemicals identified in human biological media: a data base. Third annual report, October 1981

Description: Data from almost 1600 of the 3800 body-burden documents collected to date have been entered in the data base as of October 1981. The emphasis on including recent literature and significant research documents has resulted in a chronological mix of articles from 1974 to the present. When body-burden articles are identified, data are extracted and entered in the data base by chemical and tissue/body fluid. Each data entry comprises a single record (or line entry) and is assigned a record number. I… more
Date: December 1, 1981
Creator: Cone, M.V.; Baldauf, M.F. & Martin, F.M. (comps.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Moment series for the coefficient of variation in Weibull sampling

Description: For the 2-parameter Weibull distribution function F(t) = 1 - exp(-t/b)/sup c/, t > 0, with c and b positive, a moment estimator c* for c is the solution of the equationGAMMA(1 + 2/c*)/GAMMA/sup 2/ (1 + 1/c*) = 1 + v*/sup 2/ where v* is the coefficient of variation in the form ..sqrt..m/sub 2//m/sub 1/', m/sub 1/' being the sample mean, m/sub 2/ the sample second central moment (it is trivial in the present context to replace m/sub 2/ by the variance). One approach to the moments of c* (Bowman a… more
Date: January 1, 1981
Creator: Bowman, K.O. & Shenton, L.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electron interactions with polar molecules

Description: A description is given of a number of the features of discrete and continuous spectra of electrons interacting with polar molecules. Attention is focused on the extent to which theoretical predictions concerning cross sections, resonances, and bound states are strongly influenced by the various approximations that are so ubiquitous in the treatment of such problems. Similarly, threshold scattering and photodetachment processes are examined for the case of weakly bound dipole states whose higher… more
Date: January 1, 1981
Creator: Garrett, W. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Correlation theory applied to the static and dynamic properties of EuO and EuS

Description: The paramagnetic scattering was recently measured for EuO. It was found that spin-wave-like excitations develop for wave vectors approaching the zone boundary. The spectrum was found to be well described by damped harmonic oscillators (also called the two-pole-approximation). This approximation was used previously in the correlation theory primarily to calculate static properties. Selfconsistent dynamic and static calculations have been performed for EuO, which is an ideal Heisenberg magnet wit… more
Date: October 1, 1981
Creator: Lindgard, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Data acquisition system for the HHIRF spin spectrometer

Description: The Spin Spectrometer at the Holifield Heavy Ion Research Facility (HHIRF) is a multidetector ..gamma..-ray spectrometer consisting of 72 separate NaI detector elements closely packed in a 4..pi.. geometry. The basic apparatus was constructed at Washington University and has been installed and implemented at the HHIRF at Oak Ridge National Laboratory. The spectrometer was designed especially for the investigation of the mechanisms of heavy-ion induced nuclear reactions and of the structure of n… more
Date: May 28, 1981
Creator: Hensley, D.C.
Item Type: Refine your search to only Article
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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Relevance of long-term carcinogenic and genetic hazards to emergency control

Description: This paper concentrates on how various factors may influence the risk estimates for human exposure to ionizing radiations in general, rather than on one specific nuclear event on a model population. Discussion is related to exposures to external low linear energy transfer radiation and the various parameters that affect human response. (PSB)
Date: January 1, 1981
Creator: Fry, R.J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hydrogeochemical and stream sediment reconnaissance basic data for Carlsbad quadrangle, New Mexico

Description: Field and laboratory data are presented for 467 water samples and 1680 sediment samples from the Carlsbad Quadrangle, New Mexico. The samples were collected and uranium analysis performed by Los Alamos National Laboratory; multielement analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee.
Date: August 31, 1981
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Creep properties of forged 2219 T6 aluminum alloy shell of general-purpose heat source-radioisotope thermoelectric generator

Description: The shell (2219 T6 aluminum forging) of the General Purpose Heat Source-Radioisotope Thermoelectric Generator was designed to retain the generator under sufficient elastic stress to secure it during space flight. A major concern was the extent to which the elastic stress would relax by creep. To determine acceptability of the shell construction material, the following proof tests simulating service were performed: 600 h of testing at 270/sup 0/C under 24.1 MPa stress followed by 10,000 h of sto… more
Date: December 1, 1981
Creator: Hammond, J.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sagittal focusing of synchrotron x radiation with curved crystals

Description: We describe the sagittal focusing of x rays with singly bent crystals that accept the meridian plane divergence from a similar but flat crystal to form a pair in a nondispersive two-crystal Bragg monochromator. Curved crystals can intercept from 5 to 20 times the sagittal divergence of curved mirrors at x-ray energies above 10 keV. Anticlastic (transverse) bending of the crystal is made negligible in the meridian plane with reinforcing ribs cut parallel to the plane of scattering. Results show … more
Date: January 1, 1981
Creator: Sparks, C. J., Jr.; Ice, G. E.; Wong, J. & Batterman, B. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gas cooled fast reactor control rod drive mechanism deceleration unit. Test program

Description: This report presents the results of the airtesting portion of the proof-of-principle testing of a Control Rod Scram Deceleration Device developed for use in the Gas Cooled Fast Reactor (GCFR). The device utilizes a grooved flywheel to decelerate the translating assembly (T/A). Two cam followers on the translating assembly travel in the flywheel grooves and transfer the energy of the T/A to the flywheel. The grooves in the flywheel are straight for most of the flywheel length. Near the bottom of… more
Date: October 1, 1981
Creator: Wagner, T.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimization of electrochemical-etching parameters for highly sensitive CR-39 fast neutron dosimeters

Description: Voltage gradient and frequency were studied for their influence on the electrochemical etching of CR-39 plastic irradiated with fission spectrum, fast neutrons. A power supply having outputs of up to 1.5 kV (rms) and 5 kHz was used. Differential leakage current measurements under non-etching conditions indicated that the optimal values in electrochemical etching would be 20 kV/cm and 1.3 kHz. That these parameters produced a maximum sensitivity was verified in subsequent electrochemical etching… more
Date: January 1, 1981
Creator: Gammage, R.B. & Chowdhury, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Collisional-electron detachment of Cl/sup -/ on diatomic molecules

Description: Recent experimental results for collisional-electron detachment of Cl/sup -/ by H/sub 2//D/sub 2/, N/sub 2/, O/sub 2/, NO, and CO are discussed. The emphasis is on angular distributions and energy loss measurements for laboratory energies of a few hundred eV. Evidence for the possibility of bound excited states of N/sub 2/Cl and COCl and the role of target negative-ion resonant states is presented.
Date: January 1, 1981
Creator: Annis, B.K. & Datz, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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QA engineering for the LCP USA magnet manufacturers

Description: This paper describes the QA and QC efforts and results used in fabricating the superconducting magnets of competing designs being developed by American Manufacturers for testing in the ORNL Large Coil Test Facility. Control of the design, materials and processes to assure proper functioning of the magnets in the test facility as well as the content of archival data being compiled is discussed.
Date: January 1, 1981
Creator: Childress, C.E.; Batey, J.E. & Burn, P.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electronegative gases

Description: Recent knowledge on electronegative gases essential for the effective control of the number densities of free electrons in electrically stressed gases is highlighted. This knowledge aided the discovery of new gas dielectrics and the tailoring of gas dielectric mixtures. The role of electron attachment in the choice of unitary gas dielectrics or electronegative components in dielectric gas mixtures, and the role of electron scattering at low energies in the choice of buffer gases for such mixtur… more
Date: January 1, 1981
Creator: Christophorou, L.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of precipitate-matrix interface sinks on the growth of voids in the matrix

Description: A qualitative discussion of the differing roles played by coherent and incoherent precipitates as point defect sinks is presented. Rate theory is used to obtain semiquantitative estimates of the growth of cavities in the matrix when either type of precipitate is present. Methods for deriving the sink strengths of precipitates of arbitrary shape are developed. In three materials where available microstructural information allows an analysis, precipitates are found to cause only a small relative … more
Date: January 1, 1981
Creator: Brailsford, A.D. & Mansur, L.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Learning from numerical calculations of ion-atom collisions

Description: Violent collision of two independent many-particle systems, victims, are discussed in the atomic sphere. The asymmetric region where the charge of the projectile Z/sub p/ is less than the target nuclear charge Z/sub n/ is now well understood though interesting details still need to be worked out. Negatively charged projectiles offer a new illustration of Fadeev re-arrangement collisions. Multi-electron coherence effects illustrate the richness of the field but a symmetric (Z/sub p/ approx. Z/su… more
Date: January 1, 1981
Creator: Reading, J.F.; Ford, A.L.; Martir, M. & Becker, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Role of animal studies in low-dose extrapolation

Description: Current data indicate that in the case of low-LET radiation linear, extrapolation from data obtained at high doses appears to overestimate the risk at low doses to a varying degree. In the case of high-LET radiation, extrapolation from data obtained at doses as low as 40 rad (0.4 Gy) is inappropriate and likely to result in an underestimate of the risk.
Date: January 1, 1981
Creator: Fry, R.J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Large climate-moderating envelopes for enclosed structures: a preliminary evaluation of energy conservation potential

Description: An investigation was made of the basic impacts of putting a large secondary enclosure around a number of functions and thereby creating a Large Climate Moderating Envelope (LCME). This study is a preliminary estimate of the energy conservation benefits of an LCME. A hypothetical LMCE design was chosen and a coupled fluid dynamic and energy transport analysis was performed to estimate the energy conservation potential of this design. The heat transfer models included insolation, outside air temp… more
Date: December 1, 1981
Creator: Wendt, R. L.; Giles, G. E. & Park, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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