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Control of radionuclide migration in soil by the application of dc electric current

Description: Shallow land burial in humid regions as a disposal method for low-level solid waste provides the potential for water-driven migration of leachable radionuclides present in the waste. A number of methods to control this migration have been suggested and studied. One such method involves the use of a dc electric current to move ions countercurrent to the water flow. Laboratory studies using trays of soil indigenous to the Oak Ridge National Laboratory (ORNL) low-level burial grounds have shown /sup 137/Cs, /sup 90/Sr, and /sup 99/Tc ions can be moved countercurrent to a water flow using small dc currents of 20 mA at 40 volts. A field test of the method has been under way for over one year in an ORNL low-level waste disposal area. Results of the field test are given in this paper.
Date: January 1, 1979
Creator: Case, F.N. & Cutshall, N.H.
Partner: UNT Libraries Government Documents Department

Critical concentrations of cadmium in human liver and kidney measured by prompt-gamma neutron activation

Description: Few data exist on Cd metabolism in human beings. In particular, data are needed on the role of parameters such as age, sex, weight, diet, smoking habits, and state of health. Prompt-gamma neutron activation analysis (PGNAA) provides the only currently available means for measuring in vivo levels of liver and kidney Cd. The method employs an 85 Ci, /sup 235/Pu,Be neutron source and a gamma ray detection system consisting of two Ge(Li) detector. The dose delivered to the liver and left kidney is 666 mrem (detection limit is 1.4 ..mu..g/g Cd in the liver and 2.0 mg Cd for one kidney). Absolute levels of Cd in the kidney and concentrations of Cd in the liver were measured in vivo in twenty healthy adult males using /sup 238/Pu,Be neutron sources. Organ Cd levels of smokers were significantly elevated above those of nonsmokers. Biological half-time for Cd in the body was estimated to be 15.7 yr. Cigarette smoking was estimated to result in the absorption of 1.9 ..mu..g of Cd per pack. No relationship was bound between body stores of Cd (liver and kidney) and Cd or ..beta..-microglobulin levels in urine and blood. Currently the above neutron activation facility is being mounted on a 34-ft mobile trailer unit. This unit will be used to monitor levels of Cd in industrial workers. It is anticipated that critically important data, particularly on industrially exposed workers, will provide a better basis for determining critical concentrations and for the setting or revision of standards for industrial and environmental Cd pollution. (ERB)
Date: January 1, 1979
Creator: Cohn, S.H.; Vartsky, D.; Yasumura, S.; Zanzi, I. & Ellis, K.J.
Partner: UNT Libraries Government Documents Department

Cross section measurement for the /sup 52/Cr(n,p)/sup 52/V reaction near threshold

Description: Cross sections for this reaction were determined in the range 5.3 to 9 MeV using a previously-reported pulsed-accelerator technique to measure gamma ray activity from 3.75 m /sup 52/V. Very few experimental data have been reported for this reaction, and little was known about the threshold region prior to the present experiment. The results of this work (in conjunction with other available cross section information) were used in the computation of fission-spectrum averages which are of interest for reactor applications.
Date: January 1, 1979
Creator: Smith, D.L. & Meadows, J.W.
Partner: UNT Libraries Government Documents Department

Determination of the location and connectivity of fractures in metamorphic rock with in-hole tracers

Description: A detailed investigation of the geohydrology of slightly fractured metamorphic rock by means of exploratory boreholes involves three steps: first, determining the exact location and character of the fractures penetrated by exploratory boreholes; second, determining the nature and connectivity of fractures between boreholes; third, determining the hydraulic parameters. This paper describes methods of determining the first of these, including core inspection, geophysical logs, packer tests, in-hole tracer tests, and dry drilling. Emphasis is given to the in-hole tracer tests by using an example from an investigation of slightly fractured metamorphic rock at the Savannah River Plant near Aiken, South Carolina, U.S.A. 7 figures, 2 tables.
Date: January 1, 1979
Creator: Marine, I.W.
Partner: UNT Libraries Government Documents Department

Development of chemical isolation and concentration techniques for Tc-99 analysis by resin-bead mass spectrometry

Description: A novel, highly sensitive, isotope-dilution analytical technique for the determination of technetium-99 has been developed around single ion-exchange bead mass spectrometry. Mass spectrometry is much more sensitive than direct counting for the low-energy, low-specific activity, Tc-99 isotope. Further, the point source provided by a single ion-exchange bead leads to a greater signal-to-noise ratio in the mass spectrometric measurement than does conventional application of a solution to the source filament. Recent results indicate a sensitivity greater than 0.1 picogram. Isolation of technetium from the samples occurs after addition of Tc-97 as a yield tracer. A combination of ion-exchange chromatography and ion-association solvent extraction provides decontamination from the potential interferences, Mo-97 and Ru-99. Subsequently, the technetium is loaded onto a pair of anion-exchange beads (diameter approx. 0.3 mm). The noncritical isolation and bead-loading scheme typically concentrates the technetium in the sample by a factor of about a million with overall recoveries exceeding 50%. A variety of environmental samples from the Savannah River Plant (SRP) has been analyzed by this method.
Date: January 1, 1979
Creator: Anderson, T.J.
Partner: UNT Libraries Government Documents Department

Development of resin-bead isotope-dilution mass spectrometric techniques for Tc-99 analysis

Description: An isotope dilution mass spectrometric method was developed for the analysis of Tc-99 after isolating it onto anion exchange resin beads. A single resin bead containing Tc-99 and Tc-97 spike is loaded onto a rhenium V-shaped filament for thermal emission mass spectrometry. The application of this technique requires the use of a mass spectrometer of high abundance sensitivity and pulse counting capability for the necessary ion detection sensitivity. This paper discusses the development of the technique, including the mass spectrometer, choice of filament material, scanning modes, interferences, and present achievable sample sensitivities.
Date: January 1, 1979
Creator: Walker, R.L.
Partner: UNT Libraries Government Documents Department

Discrepancy between differential and integral results for the /sup 63/Cu(n,. cap alpha. )/sup 60/Co cross sections. [Threshold to 10 MeV]

Description: The threshold-reaction /sup 63/Cu(n,..cap alpha..)/sup 60/Co is of special importance in reactor dosimetry for long-term fast-flux integration. The inconsistency in the available differential and integral data base has limited the applicability of that reaction as a reliable monitor. The availability of results from a recent measurement of the excitation function for the reaction /sup 63/Cu(n,..cap alpha..) at ANL prompted a further investigation of this problem. The implications of the new data are discussed. 24 references.
Date: January 1, 1979
Creator: Winkler, G.; Smith, D.L. & Meadows, J.W.
Partner: UNT Libraries Government Documents Department

Dynamics of nuclear fission and heavy-ion reactions

Description: Large-amplitude collective motion in fission and heavy-ion reactions is studied by solving classical equations of motion for the time evolution of the nuclear shape. In the nuclear potential energy of deformation, the generalized surface energy was calculated by means of a double volume integral of a Yukawa-plus-exponential function, which was obtained by requiring that two semi-infinite slabs of constant-density nuclear matter have minimum energy at zero separation. The collective kinetic energy is calculated for nuclear flow that is a superposition of incompressible, nearly irrotational collective-shape motion and rigid-body rotation. Nuclear dissipation is included by means of the Rayleigh dissipation function, which depends upon the physical mechanism that converts collective energy into internal energy. For both ordinary two-body viscosity and a combined wall and window one-body dissipation, fission-fragment kinetic energies are calculated for the fission of nuclei throughout the periodic table and compare with experimental results. Finally, the one-body dynamics of nucleons inside a cylinder colliding with a moving piston is explicitly studied by solving exactly the collisionless Boltzmann equation for the distribution function. By examining the relative phases of the pressure at the piston and the piston's velocity, a dissipative force and an elastic restoring force can be separately identified. 9 references.
Date: January 1, 1979
Creator: Nix, J.R. & Sierk, A.J.
Partner: UNT Libraries Government Documents Department

Efficient microscale preparation of tin-117m-tin tetrachloride-a pivotal intermediate for the synthesis of tin-117m-labeled radiopharmaceuticals

Description: A microscale technique has been developed for the preparation of /sup 117m/SnCl/sub 4/. The radiolabeled tin tetrachloride is an important intermediate for the synthesis of /sup 117m/Sn-labeled organic radiopharmaceuticals. The flow-through system involves high temperature chlorination of metallic /sup 117m/Sn with subsequent cryogenic collection of the /sup 117m/SnCl/sub 4/ in a special reaction vessel. This vessel can then be used for the conversion of the tin tetrachloride to various useful intermediates. The reactions that have been studied include the formation of tetraalkyl and tetraaryltin compounds by reaction of SnCl/sub 4/ with Grignard or alkyl and aryl lithium reagents (SnCl/sub 4/ ..-->.. R/sub 4/Sn or Ar/sub 4/Sn). In addition, by stoichiometric control, the comproportionation of SnCl/sub 4/ with tetramethyltin can yield any one of the mixed methylchlorotin intermediates, MeSnCl/sub 3/, Me/sub 2/SnCl/sub 2/, or Me/sub 3/SnCl. These products are important intermediates for the preparation of /sup 117m/Sn-labeled steroids, fatty acids, amino acids, barbituates, and a variety of other potentially useful agents.
Date: January 1, 1979
Creator: Woo, D.V.; Knapp, F.F. Jr.; Butler, T.A. & Callahan, A.P.
Partner: UNT Libraries Government Documents Department

ENDF/B-V neutron cross section evaluation for the krypton isotopes. [10/sup -5/ eV to 20 MeV]

Description: The evaluation of the neutron cross-section data for the six stable isotopes of Kr from 10/sup -5/ eV to 20 MeV is described. These evaluations incorporate all the new data on these isotopes, including those on the resonance parameters, level schemes of the various isotopes and residual nuclei, and reaction data. Evaluation procedures adopted to assess experimental data and the nuclear model calculations used are described. 67 figures, 6 tables.
Date: January 1, 1979
Creator: Prince, A.
Partner: UNT Libraries Government Documents Department

Environmental consequences of atmosphereic krypton-85. Final report, January 1, 1977-September 30, 1979

Description: Krypton-85 is a radioactive inert gas produced during normal operations of the nuclear fuel cycle. The quantities of krypton-85, that will be produced in the next century, are sufficient, if released, to alter the electrical state of the atmosphere. The principal hypothesis is that an anthropogenic alteration of the electric state of the atmosphere could alter other meterological phenomena and lead to significant environmental impacts. The goal of this project was to explore some areas of basic science related to the evaluation of that hypothesis. The approach was primarily theoretical. The following topics were addressed: a first approximation model to estimate the effects of krypton-85 on the electrical state of the atmosphere; an analysis of the pathways between krypton-85 production and the atmosphere; an analytical model for fair weather atmospheric electricity; and a dipole model for atmospheric electricity. The results will provide a framework on which detailed models can be built. The results should provide better understanding of some topics in atmospheric electricity.
Date: January 1, 1979
Creator: Boeck, W.L.
Partner: UNT Libraries Government Documents Department

Evaluation of radiolabeled ruthenium compounds as tumor-localizing agents

Description: This work introduces a new class of radiopharmaceuticals based on ruthenium-97. The excellent physical properties of Ru-97, the high chemical reactivity of Ru, the potential antitumor activity of several Ru coordination compounds, and BLIP production of Ru-97, provide a unique combination for the application of this isotope in nuclear oncology. A systematic study was undertaken on the synthesis, characterization, and evaluation of a number of ruthenium-labeled compounds. In a variety of animal tumor models, several compounds show considerable promise as tumor-localizing agents when compared to gallium-67 citrate. The compounds studied (with Ru in different oxidation states) include ionic Ru, a number of hydrophilic and lipophilic chelates, and various ammine derivatives.
Date: January 1, 1979
Creator: Srivastava, S.C.; Richards, P.; Meinken, G.E.; Som, P.; Atkins, H.L.; Larson, S.M. et al.
Partner: UNT Libraries Government Documents Department

Evaluation of the health hazard from inhaled krypton-85

Description: Evaluation of the degree of internal radiation hazard requires knowledge of the parameters of Kr-85 metabolism in human beings. Data on the rate of saturation and desaturation of the body tissues are required for this estimation. The object of this in vivo study was to characterize the metabolism of inhaled Kr. For this purpose, measurements were made of the distribution and clearance of Kr following inhalation of /sup 79/Kr by the normal subjects. The rate constants determined for /sup 79/Kr were used to calculate the radiation dose associated with exposure to the long-lived /sup 85/Kr. The retention data were obtained with the Brookhaven whole-body counter. The clearance of /sup 79/Kr from the body indicates five components ranging in half-times from 14 sec to 9.6 h. The slowest components, varying between 4.2 and 9.6 h, correlated highly with percent body fat. The long-term retention was localized in regions of high fat content. The stimated radiation dose based on the retention data of this study indicates that doses to body fat and gonads are larger than those estimated by other investigators. This increased estimated dose derives from the increase in retention time of krypton in fat pools.
Date: January 1, 1979
Creator: Cohn, S.H.; Ellis, K.J. & Susskind, H.
Partner: UNT Libraries Government Documents Department

Fast neutron capture cross section measurements, evaluations and model calculations of fission product nuclei. [0. 5 to 4. 0 MeV]

Description: The fast-neutron capture cross sections of elemental rhodium, palladium, neodymium, and samarium were measured in the energy range 0.5 to 4.0 MeV relative to the standard capture cross section of gold. A large liquid scintillator and the time-of-flight technique were used in these measurements. Experimental data are rare or non-existent in this energy range and evaluations differ substantially, with a factor of 5 being common. The present data were used together with other experimental data and nuclear model calculations in order to provide a consistent set of isotopic and elemental capture cross sections. 5 figures.
Date: January 1, 1979
Creator: Poenitz, W.P.
Partner: UNT Libraries Government Documents Department

Fast neutron total and scattering cross sections of chromium, iron and /sup 60/Ni. [50 to 100 keV]

Description: Neutron total cross sections are measured with broad resolutions (50 to 100 keV) from approx. = 1.0 to 4.5 MeV at intervals of less than or equal to 50 keV and to accuracies of approx. = 1%. Differential elastic scattering cross sections are measured at greater than or equal to 10 scattering angles distributed between 20 and 160/sup 0/ from approx. = 1.5 to 4.0 MeV at intervals of less than or equal to 50 keV. Angle-integrated elastic scattering cross sections are deduced from the measured values to accuracies of greater than or equal to 5%. Inelastically scattered neutrons are observed up to incident neutron energies of 4.0 MeV at scattering angles distributed between 20 and 160/sup 0/. Cross sections are determined corresponding to the excitation of observed states at: Chromium - 1433, 2377, 2665, 2778, and 2970 keV; Iron - 853, 1389, 2097, 2579, 2677, 2974, and 3152 keV; and /sup 60/Ni - 1342, 2168, 2304, 2509, 2636, and 3164 keV. The experimental results are discussed in terms of conventional optical-statistical models and in the context of direct-scattering processes. The experimental and calculational results are compared with the corresponding evaluated quantities given in the ENDF/B file. 21 references.
Date: January 1, 1979
Creator: Smith, A B; Guenther, P T & Whalen, J F
Partner: UNT Libraries Government Documents Department

Fast-neutron total and scattering cross sections of Cr, Fe and /sup 60/Ni. [1 to 4. 5 MeV]

Description: Neutron total cross sections are measured with broad resolutions (50 to 100 keV) from approx. = 1.0 to 4.5 MeV at intervals of less than or equal to 50 keV and to accuracies of approx. = 1% using a variety of sample thicknesses. Differential elastic-scattering cross sections are measured at greater than or equal to 10 scattering angles distributed between 20 to 160 deg. from approx. = 1.5 to 4.0 MeV at intervals of less than or equal to 50 keV. Angle-integrated elastic scattering cross sections are deduced from the measured values to accuracies greater than or equal to 5%. Inelastic-neutron-scattering cross sections are determined up to incident neutron energies of 4.0 MeV, at scattering angles distributed between 20 to 160 deg., and for 5 observed excitations in Cr, for 7 in Fe and for 6 in /sup 60/Ni. The experimental results are discussed in terms of conventional optical-statistical models with attention to cross section fluctuations and in the context of direct-scattering processes. The experimental and calculational results are compared with the corresponding evaluated quantities given in the ENDF/B file with attention to regions of agreement and inconsistency. 14 references.
Date: January 1, 1979
Creator: Smith, A.B.; Guenther, P.T. & Whalen, J.F.
Partner: UNT Libraries Government Documents Department

Giant resonances excited by heavy-ions

Description: The potential of heavy-ion inelastic scattering as a method for studying giant resonance spectroscopy is investigated and compared to results obtained with the (..cap alpha..,..cap alpha..') reaction. Optical model calculations reveal a strong dependence of the excitation cross sections upon bombarding energy. Differences between the backgrounds encountered in light and heavy hadron scattering experiments are discussed. 35 references.
Date: January 1, 1979
Creator: Sandorfi, A.M.
Partner: UNT Libraries Government Documents Department

Grain-boundary diffusion: structural effects, models and mechanisms

Description: Grain boundary diffusion phenomena were considered including: anisotropy, effect of orientation, crystallographic transformation, boundary type, dislocation dissociation, pressure, and isotope effects. Diffusivity is different for various boundaries. Dissociated dislocations and stacking faults are not efficient paths for grain boundary diffusion. Results suggest a vacancy mechanism along the dislocation core, and involves atomic jumps away from the back towards the dislocation as well as jumps along the core. Measurements were made on nickel and silver. (FS)
Date: January 1, 1979
Creator: Peterson, N L
Partner: UNT Libraries Government Documents Department

Hydrodynamic model wavefunctions in intrinsic coordinates and their application to the structure of even-even nuclei. [Quadrupole-vibration Hamiltonian, model energies, E2 transition rates]

Description: A closed expression is presented for intrinsic-coordinate (..beta.., ..gamma.., theta/sub i/) eigenfunctions of the hydrodynamic, quadrupole-vibration Hamiltonian of A. Bohr. These functions are used as an expansion basis for the treatment of more general collective Hamiltonians. Two classes of such Hamiltonians are considered. In each the potential energy term of the Bohr Hamiltonian, 1/2 C..beta../sup 2/, was replaced with a more general function of the shape coordinates, V(..beta.., ..gamma..). The potential of Gneuss and Greiner (1) is used to demonstrate the soundness of the calculational techniques, and to illustrate convergence properties of calculated energies. Potentials possessing a single minimum on 0 less than or equal to ..gamma.. less than or equal to 60/sup 0/ are considered through the study of a quadratic-potential (QP) Hamiltonian. The smooth development from spherical to asymmetrically deformed nuclear shapes is investigated by systematically varying the parameters ..beta../sub 0/ and C/sub ..gamma../. Model energies and E2 transition rates are traced during this process. The QP model is then applied to /sup 106/Pd, /sup 166/Er, /sup 182/W, /sup 122/Te, and /sup 186/ /sup 188/ /sup 190/ /sup 192/Os. Low-energy ..gamma.. vibrations appear to play a prominent role in the latter five nuclei, and the QP model offers a better accounting of experimental spectra than does the model of Davydov and Chaban (2). 74 references.
Date: January 1, 1979
Creator: Margetan, F.J.
Partner: UNT Libraries Government Documents Department

Hydrogen absorption in the niobium--vanadium system

Description: The effect of dilute vanadium additions to niobium on hydrogen absorption has been studied by measuring equilibrium pressure--composition--temperature data for a Nb + 6 at.% V alloy and by constructing a theoretical model of the effect of hydrogen trapping on phase equilibria in such systems. The results indicate the H--V binding energy is substantially smaller than thought previously. A depression of the ..cap alpha..--..cap alpha..' critical temperature is observed which, if interpreted in terms of trapping, leads to a H--V binding energy of approx. 0.04 eV.
Date: January 1, 1979
Creator: Pick, M A & Welch, D O
Partner: UNT Libraries Government Documents Department

Hyper fuse: a novel inertial confinement system utilizing hypervelocity projectiles for fusion energy production and fission waste transmutation

Description: Parametric system studies of an inertial confinement fusion (ICF) reactor system to transmute fission products from an LWR economy have been carried out. The ICF reactors would produce net power in addition to transmuting fission products. The particular ICF concept examined is an impact fusion approach termed HYPERFUSE, in which hypervelocity pellets, traveling on the order of 100 to 300 km/sec, collide with a target in a reactor chamber and initiate a thermonuclear reaction. The DT fusion fuel is contained in a shell of the material to be transmuted, e.g., /sup 137/Cs or /sup 90/Sr. The 14 MeV fusion neutrons released during the pellet burn cause transmutation reactions (e.g., (n, 2n), (n, ..cap alpha..), etc.) that convert the long lived fission products (FP's) either to stable products or to species that decay with a short half-life to a stable product.
Date: January 1, 1979
Creator: Makowitz, H; Powell, J R & Wiswall, R
Partner: UNT Libraries Government Documents Department

Imprecision of dose predictions for radionuclides released to the atmosphere: an application of the Monte Carlo-simulation-technique for iodine transported via the pasture-cow-milk pathway

Description: The shortcomings of using mathematical models to determine compliance with regulatory standards are discussed. Methods to determine the reliability of radiation assessment models are presented. Since field testing studies are impractical, a deficiency method, which analyzes the variability of input parameters and the impact of their variability on the predicted dose, is used. The Monte Carlo technique is one of these methods. This technique is based on statistical properties of the model output when input parameters inserted in the model are selected at random from a prescribed distribution. The one big assumption one must make is that the model is a correct formulation of reality. The Gaussian plume model for atmospheric transport of airborne effluents was used to study the pasture-cow-milk-man exposure pathway and the dose calculated from radioiodine (/sup 131/I) transported over this pathway. (DMC)
Date: January 1, 1979
Creator: Schwarz, G. & Hoffman, F.O.
Partner: UNT Libraries Government Documents Department

In-situ verification techniques for fast critical assembly cores

Description: Active and passive autoradiographic techniques were used to obtain piece counts of fuel plates in fast critical assembly drawers and to verify the assembly loading pattern. Active autoradiography using prompt-fission and fission-product radiation was more successful with uranium fuel while passive autoradiography was more successful with plutonium fuel. A source multiplication technique was used to measure changes in reactivity when small quantities (2-2.5 kg) of fissile material were removed from a subcritical reference core of the Zero Power Plutonium Reactor. Efforts to compensate for unsuccessful. Some compensation was achieved by replacing U-238 with polyethylene. The sensitivity for detection of partially compensated fuel removed from minimum worth regions was approximately 2.5 kg (fissile) for a core containing 2600 kg (fissile). Substitution of polyethylene was detected with a spectral index which was the ratio of the rate of the In-115 (n,..gamma..) reaction to the rate of the In-115 (n,n') reaction. This spectral index was sensitive to the presence of an 0.64-cm-thick, 5.08-cm-high polyethylene column 10-15 cm away from the indium foil. The reactivity worth of Pu-239 was also obtained as a function of location in the reactor core with the use of an inverse kinetics technique. Reactivity worths for Pu-239 varied from a maximum of 58.67 Ih/kg near the core center to a minimum of 14.86 Ih/kg at the core edge.
Date: January 1, 1979
Creator: Brumbach, S.B.; Amundson, P.I. & Roche, C.T.
Partner: UNT Libraries Government Documents Department