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in subjects: "Internal Conversion"

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Disposal of Iodine-129

One of the problems to be solved in the nuclear waste management field is the disposal of radioactive iodine-129, which is one of the more volatile and long-lived fission products. Studies have shown that fission products can be fixed in concrete for permanent disposal. Current studies have demonstrated that practical cementitious grouts may contain up to 18% iodine as barium iodate. The waste disposal criterion is based on the fact that harmful effects to present or future generations can be a… more

Date: January 1, 1978

Creator: Morgan, M. T.; Moore, J. G.; Devaney, H. E.; Rogers, G. C.; Williams, C. & Newman, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Use of fluorescent screens for isotope radiography

Radiographic examination can be performed on items beyond the limitation of conventional isotope radiography without a great loss of resolution. With proper film and screen selection and scatter radiation control, fluorescent screens can be a valuable additional tool for radiography.

Date: January 1, 1979

Creator: Hubbard, S. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Reaction studies of hot silicon and germanium radicals. Progress report, September 1, 1978-August 31, 1979

The experimental approach to attaining the goals of this research program is briefly outlined and the progress made in the last year is reviewed in sections entitled: (a) Primary steps in the reaction of recoiling silicon and germanium atoms and the identification of reactive intermediates; (b) Thermally induced silylene and germylene reactions; (c) Silicon free radical chemistry; (d) The role of ionic reactions in the chemistry of recoiling silicon atoms.

Date: August 31, 1979

Creator: Gaspar, P. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Active neutron multiplicity counting of bulk uranium

This paper describes a new nondestructive assay technique being developed to assay bulk uranium containing kilogram quantities of {sup 235}U. The new technique uses neutron multiplicity analysis of data collected with a coincidence counter outfitted with AmLi neutron sources. We have calculated the expected neutron multiplicity count rate and assay precision for this technique and will report on its expected performance as a function of detector design characteristics, {sup 235 }U sample mass, … more

Date: January 1, 1991

Creator: Ensslin, N.; Krick, M. S.; Langner, D. G. & Miller, M. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Amorphous Ge bipolar blocking contacts on Ge detectors

Semiconductor nuclear radiation detectors are usually operated in a full depletion mode and blocking contacts are required to maintain low leakage currents and high electric fields for charge collection. Blocking contacts on Ge detectors typically consist of n-type contacts formed by lithium diffusion and p-type contacts formed by boron ion implantation. Electrical contacts formed using sputtered amorphous Ge (a-Ge) films on high-purity Ge crystals were found to exhibit good blocking behavior i… more

Date: October 1, 1991

Creator: Luke, P. N.; Cork, C. P.; Madden, N. W.; Rossington, C. S. & Wesela, M. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Three-step photoionization of mercury for application to separation of mercury isomers

Development of techniques for separating isomeric nuclides is important to the investigation of schemes for gamma-ray lasers. In preparation for an experiment to separate 10/sup 14/ atoms of the /sub 197m/Hg (299 keV, tau/sub 1/2/ = 24 hours) isomer, we report isotopically selective resonance ionization of mercury atoms. This has been accomplished by three-step excitation via the 6/sup 3/P/sub 1/ and 8/sup 1/S/sub 0/ excited states, using three collinear pulsed laser beams of 254, 286, and 532 … more

Date: January 1, 1982

Creator: Dyer, P.; Baldwin, G.C. & Kittrell, C.p

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Angular Momentum in Subbarrier Fusion

We have measured the ratio of the isomer to ground-state yields of {sup 137}Ce produced in the fusion reactions {sup 128}Te({sup 12}C,3n), {sup 133}Cs({sup 7}Li,3n), {sup 136}Ba({sup 3}He,2n), {sup 136}Ba({sup 4}He,3n), and {sup 137}Ba({sup 3}He,3n), from energies above the Coulomb barrier to energies typically 20--30% below the barrier by observing the delayed x- and {gamma}-ray emission. We deduce the average angular momentum, {lt}J{gt}, from the measured isomer ratios with a statistical mode… more

Date: May 1, 1990

Creator: DiGregorio, D. E.; Lesko, K. T.; Harmon, B. A.; Norman, E. B.; Pouliot, J.; Sur, B. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Reaction studies of hot silicon and germanium radicals. Period covered: September 1, 1977--August 31, 1978

The experimental approach to attaining the goals of this research program is briefly outlined and the progress made in the last year is reviewed in sections entitled: primary steps in the reaction of recoiling silicon and germanium atoms and the identification of reactive intermediates; thermally induced silylene and germylene reactions; the role of ionic reactions in the chemistry of recoiling silicon atoms and other ion-molecule reactions studies; and silicon free radical chemistry.

Date: August 31, 1978

Creator: Gaspar, P.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Reaction studies of hot silicon and germanium radicals. Progress report, September 1, 1975--August 30, 1976

The experimental approach to attaining the goals of this research program is briefly outlined, and the progress made in the last year is reviewed in sections entitled: (a) Primary steps in the reactions of recoiling silicon and germanium atoms and the identification of reactive intermediates; (b) Thermally induced silylene reactions; (c) The role of ionic reactions in the chemistry of recoiling silicon atoms and other ion-molecule reaction studies.

Date: August 30, 1976

Creator: Gaspar, P. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Thermodynamics and surface structure of coals

We have reported the determination of the average micropore diameter of an Argonne Illinois No. 6 coal (77% C, daf) and a standard 15 A diameter Spherocarb sample by {sup 129}Xe NMR spectroscopy. We have successfully applied this technique to determine the average micropore diameter of the full series of Argonne coals. We have recently developed a computer program (Appendix A) which correlates the 129 Xe NMR spectrum of Coals directly to the micropore size distribution of each Argonne coal. The… more

Date: January 1, 1991

Creator: Glass, A. S.; Larsen, J. W.; Quay, D. M.; Roberts, J. E. & Wernett, P. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Global cycling of tritium and iodine-129

Dynamic linear compartmnt models are used widely to describe global cycling of environmental tritium and /sup 129/I. Important tests of these models by comparison of predictions with environmental data from anthropogenic sources are discussed. A tritium model, based on the global hydrologic cycle that reproduces time-series data from atmospheric nuclear weapons testing on concentrations in precipitation, ocean surface waters, and surface fresh waters in the northern hemisphere, concentrations o… more

Date: January 1, 1986

Creator: Kocher, D. C. & Killough, G. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Reaction studies of hot silicon and germanium radicals. Progress report, September 1, 1976--August 31, 1977

The experimental approach to attaining the goals of this research program is briefly outlined and the progress made in the last year is reviewed in sections entitled: (a) primary steps in the reactions of recoiling silicon and germanium atoms and the identification of reactive intermediates; (b) thermally induced silylene and germylene reactions; (c) the role of ionic reactions in the chemistry of recoiling silicon atoms and other ion-molecule reaction studies; (d) silicon free radical chemistr… more

Date: August 31, 1977

Creator: Gaspar, P. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Model of iodine transport and reaction kinetics in a nuclear fuel reprocessing plant

A model is presented to describe the time-dependent flow and retention of stable iodine isotopes and the decay of /sup 131/I in a nuclear fuel reprocessing plant. The plant consists of 16 units of equipment such as a voloxidizer or graphite burner, fuel dissolver, solvent extractors, storage tanks, vaporizers, primary iodine sorbers, and silver zeolite. The rate of accumulation of bulk and radioactive iodine in these units and in the environment is described using 19 differential equations. Rea… more

Date: May 1, 1977

Creator: Davis, W. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Surface structure and thermodynamics of coals

Our work has been the determination of the average micropore diameter of an Argonne Illinois No. 6 coal and a spherocarb sample by {sup 129}Xe NMR. {sup 129}Xe NMR spectroscopy has been used to determine pore sizes and surface characteristics in zeolites. The chemical shift of {sup 129}Xe was measured as a function of pressure and the average micropore diameter was calculated using established techniques. For the spherocarb, the calculated pore diameter of 15.4 CA agrees well with the 0 manufac… more

Date: January 1, 1989

Creator: Wernett, P. C. & Larsen, J. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Potential sources for the radiation treatment of food

A major consideration in the design of large-scale economical food irradiation systems is the radiation source. The ''traditional'' gamma radiation source, /sup 60/Co, is presently produced by the irradiation of /sup 59/Co in nuclear reactors. In addition, other radioisotopes with appropriate characteristics for food irradiation systems are presently available or may be available in the future. These radioisotopes are certain waste fission products formed in nuclear reactor fuel during operatio… more

Date: August 1, 1976

Creator: Sande, W. E. & Libby, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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PHYSICS DIVISION QUARTERLY REPORT FOR DECEMBER 1953, JANUARY AND FEBRUARY 1954

No Description Available.

Date: August 1, 1954

Item Type: Report

Partner: UNT Libraries Government Documents Department

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VARSKIN MOD 2 and SADDE MOD2: Computer codes for assessing skin dose from skin contamination

The computer code VARSKIN has been modified to calculate dose to skin from three-dimensional sources, sources separated from the skin by layers of protective clothing, and gamma dose from certain radionuclides correction for backscatter has also been incorporated for certain geometries. This document describes the new code, VARSKIN Mod 2, including installation and operation instructions, provides detailed descriptions of the models used, and suggests methods for avoiding misuse of the code. Th… more

Date: December 1, 1992

Creator: Durham, J.S. (Pacific Northwest Lab., Richland, WA (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

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

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 te… more

Date: January 1, 1979

Creator: Walker, R.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An evaluation of simple iron-water radiation shields and radiation measurements within concrete-lined and -capped pits

Program 3 of Operation BREN consisted in a study of the performance of biological shields composed of various arrangements of steel, water, and borated polyethylene in spherical, cubical, and parallelepipedal geometries. Studies were also made of the radiation levels within concrete-lined and -capped pits, 4 ft in dia and 8 ft deep. The principal radiation source was the ORNL Health Physics Research Reactor, an unshielded, unreflected, 90 wt % U-10 wt % Mo, cylindrical bare-metal assembly. It w… more

Date: July 31, 1964

Creator: Muckenthaler, F. J.; Jung, L.; Blosser, T. V.; Freestone, R. M. Jr. & Miller, J. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Study of radionuclides created by sup 181 Ta(. gamma. ,xn yp) reactions for bremsstrahlung photons produced by 150-MeV electrons

Ten radionuclides, including isomers, from {sup 172}Ta to {sup 180}Ta and {sup 180m}Hf were produced by photon interactions with a sample of elemental tantalum and measured by counting photons using a high-resolution detection system. Relative yields of these radionuclides were obtained. In addition, precision half lives were obtained for {sup 175,176,180}Ta and {sup 180m}Hf. Those obtained for the three Ta isotopes agree with previously reported values. For {sup 180m}Hf, the present measuremen… more

Date: December 1, 1991

Creator: Miller, M.A. (Wisconsin Univ., River Falls, WI (United States)) & Dickens, J.K. (Oak Ridge National Lab., TN (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High pressure /sup 129/I Moessbauer studies of GeI/sub 4/ molecular crystals

The Moessbauer effect in /sup 129/I in conjunction with Diamond-Anvil-Cell high pressure techniques was applied to investigate the high pressure phase(s) of the molecular crystal GeI/sub 4/. The /sup 129/I Quadrupole Interaction was the main probe for characterizing the intermolecular structural transformation with pressure. With increasing pressure, at about 15 GPAa, the onset of a partial molecular-association phase (HP1) is first observed. In HP1 two out of the four iodines strongly overlap … more

Date: January 1, 1989

Creator: Pasternak, M. P. & Taylor, R. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sign of the electric-field gradient at /sup 111/Cd in Zr and Sb

The ..beta..-..gamma.. TDPAC technique was applied to /sup 111/Ag implanted in Zr and Sb metal single crystals in order to determine sign and magnitude of the quadrupole interaction at the site of /sup 111/Cd in these metals. An analysis of the data taken at 293K yielded nu/sub Q/ = +15.4(6) MHz for /sup 111/Cd in Zr and nu/sub Q/ = -107.5(20) MHz for /sup 111/Cd in Sb. From these values electric field gradients of +7.3(8)x10/sup 16/ V/cm/sup 2/ and -5.56(62)x10/sup 17/ V/cm/sup 2/ for Cd in Zr… more

Date: January 1, 1983

Creator: Kaufmann, E.N.; Krien, K.; Pielen, W. & Vianden, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Relativistic many-body theory of atomic structures

The main objective of this program is to improve our understanding of the effect of relativity and electron correlations on atomic processes. Current efforts include hyperfine structure (hfs) studies using the multiconfiguration Dirac-Fock (MCDF) technique. Atomic hfs are known to be sensitive to relativity and electron correlations, and provide important tests of relativistic atomic many-body theories. Preliminary results on the hfs of the 4f/sup 12/ /sup 3/H ground state of /sub 68/Er/sup 167… more

Date: January 1, 1983

Creator: Cheng, K.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Measurement of radiation dose using radiochromic film

We have irradiated samples of radiochromic film to doses between 0.005 and lMrad in a Co[sup 60] facility at ANL. The doses computed using the manufacturer's calibration curves for the absorption at 600 and 510 nm have been compared with the dose obtained from ion chamber measurements. Excellent agreement is obtained and high precision can be maintained by baseline measurement of the films prior to irradiation, appropriate choice of film and wavelength used.

Date: November 24, 1992

Creator: Jankowski, D. J. & Proudfoot, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department