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in subjects: "Beta-Plus Decay Radioisotopes"

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Radionuclides in plankton from the South Pacific Basin

We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10/sup 4/. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northw… more

Date: March 23, 1984

Creator: Marsh, K.V. & Buddemeier, R.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advances in the Helium-Jet Coupled on-Line Mass Separator RAMA. [Recoil Atom Mass Analyzer]

General improvements to the on-line mass separator RAMA (Recoil Atom Mass Analyzer) have yielded a greater reliability and efficiency for some elements. A new utilitarian helium-jet chamber has been installed to facilitate quick target and degrader foil changes in addition to a new ion source holder. A higher efficiency hollow-cathode, cathode-extraction ion source, for lower melting point elements (< 1200/sup 0/C) has also been designed. Tests with the beta-delayed proton emitter /sup 37/Ca… more

Date: January 1, 1980

Creator: Moltz, D. M.; Aysto, J.; Cable, M. D.; Parry, R. F.; Haustein, P. E.; Wouters, J. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Emission computed tomography of /sup 18/F-fluorodeoxyglucose and /sup 13/N-ammonia in stroke and epilepsy

The ECAT Positron Tomograph was used to scan normal control subjects, stroke patients at various times during recovery, and patients with partial epilepsy during EEG monitoring. /sup 18/F-fluorodeoxyglucose (/sup 18/FDG) and /sup 13/N-Ammonia (/sup 13/NH/sub 3/) were used as indicators of abnormalities in local cerebral glucose utilization (LCMR/sub glc/) and relative perfusion, respectively. Hypometabolism, due to deactivation or minimal damage, was demonstrated with the /sup 18/FDG scan in de… more

Date: January 1, 1980

Creator: Kuhl, D. E.; Phelps, M. E. & Engel Jr., J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Short-lived positron emitter labeled radiotracers - present status

The preparation of labelled compounds is important for the application of positron emission transaxial tomography (PETT) in biomedical sciences. This paper describes problems and progress in the synthesis of short-lived positron emitter (/sup 11/C, /sup 18/F, /sup 13/N) labelled tracers for PETT. Synthesis of labelled sugars, amino acids, and neurotransmitter receptors (pimozide and spiroperidol tagged with /sup 11/C) is discussed in particular. (DLC)

Date: January 1, 1982

Creator: Fowler, J. S. & Wolf, A. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Transport and deposition of activation products in a helium cooled fusion power plant

The transport and deposition of neutron activation products in a helium cooled tokamak fusion power plant are investigated. Stainless steel is used as coolant channel material for a helium/steam system. The important gamma emitting nuclides /sup 56/Mn, /sup 54/Mn, /sup 57/Co, /sup 58/Co, /sup 60/Co, /sup 51/Cr, and /sup 99/Mo are considered. The dominant release mechanism identified is direct daughter recoil emission from (n,x) type reactions. Corrosion and evaporation are discussed. The radion… more

Date: September 1, 1980

Creator: Bickford, W.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High resolution positron Q-value measurements and nuclear structure studies far from the stability line. Progress report

Research progress in briefly described, and details are presented in the attached preprints and reprints: (1) precision mass differences in light rubidium and krypton isotopes utilizing beta endpoint measurements; (2) precision mass measurements utilizing beta endpoints; (3) Monte Carlo calculations predicting the response of intrinsic GE detectors to electrons and positrons; and (4) reactor antineutrino spectra and nuclear spectroscopy of isotopes far from beta stability. (WHK)

Date: February 28, 1982

Creator: Avignone, F. T. III

Item Type: Report

Partner: UNT Libraries Government Documents Department

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/sup 56/Ni and the light curve of Type I supernova

The explanation of SN Type I by radioactive decay of /sup 56/Ni requires a relatively small value of the transparency function M/sub ej//v/sub 9//sup 2/ = 0.22 in units of M/sub solar/'s and 10/sup 9/ cm s/sup -1/ to explain the light curve. A minimum mass of /sup 56/Ni is required to explain the peak and near peak luminosity. Subsequent radioactive decay energy must escape in some other form than optical light in order to explain the rapid early and late time decay. Early ultraviolet and infra… more

Date: July 24, 1980

Creator: Colgate, S.A. & Petschek, A.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Trends in the study of light proton rich nuclei

Recent work in light proton-rich nuclei is reviewed. Evidence for the first T/sub z/ = -5/2 nuclide, /sup 35/Ca, is presented. The mechanisms of two-proton emission following beta-decay is investigated. Future directions in this field are discussed. 23 refs., 5 figs. (WRF)

Date: September 1, 1985

Creator: Moltz, D. M.; Aysto, J.; Hotchkis, M. A. C. & Cerny, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Polarization phenomena in projectile fragmentation process

The nuclear spin polarization of beta-emitting fragments {sup 37}K and {sup 39} Ca has been measured at around the grazing angle of the {sup 40}Ca + Au collision at 106 MeV/u. Momentum dependence of the observed fragment polarization supports the idea that the origin of the polarization is the orbital angular momentum held by the fragment part of the projectile before the collision takes place. The sizable polarization of about 5% that was observed for the fragments will be a powerful tool for … more

Date: March 1, 1992

Creator: Matsuta, K.; Ozawa, A.; Nojiri, Y.; Minamisono, T.; Fukuda, M.; Kitagawa, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent experiments at Brookhaven: level structure of N = 86 isotones /sup 156/Yb and /sup 150/Gd

States of the N = 86 isotones /sup 156/Yb and /sup 150/Gd have been studied by means of the /sup 144/Sm(/sup 16/O,4n)/sup 156/Yb, /sup 113/In(/sup 46/Ti,p2n)/sup 156/Yb, and /sup 124/Sn(/sup 30/Si,4n)/sup 150/Gd reactions. Levels have been established to spin 36 h-bar and over 12.5 MeV in excitation in /sup 150/Gd and to beyond spin 25 h-bar in /sup 156/Yb. The systematics of levels in the N = 86 isotones from /sup 150/Gd to /sup 156/Yb are described, and the near-spherical shell model descript… more

Date: January 1, 1980

Creator: Sunyar, A W

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Actinide production in /sup 136/Xe bombardments of /sup 249/Cf

The production cross sections for the actinide products from /sup 136/Xe bombardments of /sup 249/Cf at energies 1.02, 1.09, and 1.16 times the Coulomb barrier were determined. Fractions of the individual actinide elements were chemically separated from recoil catcher foils. The production cross sections of the actinide products were determined by measuring the radiations emitted from the nuclides within the chemical fractions. The chemical separation techniques used in this work are described … more

Date: August 1, 1985

Creator: Gregorich, K.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiation dose estimates for copper-64 citrate in man

Tumor imaging agents suitable for use with positron emission tomographs are constantly sought. We have performed studies with animal-tumor-bearing models that have demonstrated the rapid uptake of copper-64. The radiation dose estimates for man indicate that the intravenous administration of 7.0 mCi would result in radiation doses to the kidney of 9.8 to 10.5 rads with other organs receiving substantially less radiation. 5 refs., 3 tabs.

Date: January 1, 1985

Creator: Crook, J.E.; Carlton, J.E.; Stabin, M. & Watson, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Estimating Adipose Tissue in the Chest Wall Using Ultrasonic and Alternate /sup 40/K and Biometric Measurements

The percentage of adipose (fat) tissue in the chest wall must be known to accurately measure Pu in the human lung. Correction factors of 100% or more in x-ray detection efficiency are common. Methods using simple /sup 40/K and biometric measurement techniques were investigated to determine the adipose content in the human chest wall. These methods predict adipose content to within 15% of the absolute ultrasonic value. These new methods are discussed and compared with conventional ultrasonic mea… more

Date: January 22, 1982

Creator: Anderson, A. L. & Campbell, G. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Environmental behavior of technetium in soil and vegetation: implications for radiological impact assessment

Significant radiological exposures have been estimated for hypothetical atmospheric releases of Tc-99 from gaseous diffusion facilities when vegetation-to-soil concentration ratios representative of laboratory experiments are substituted for generic default values assumed in current regulatory models. To test the relevancy of these laboratory ratios, field investigations were conducted to obtain measurements of the vegetation-to-soil concentration ratio for Tc-99 in samples collected near opera… more

Date: April 1, 1982

Creator: Hoffman, F. O.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Minimum detectable activities of contamination control survey equipment

The Instrumentation External Dosimetry (I ED) Section of the Health Physics Department at the Pacific Northwest Laboratory (PNL) has performed a series of tests to determine the ability of portable survey instruments used at Hanford to detect radioactive contamination at levels required by DOE 5480.11. This semi-empirical study combines instrumental, statistical, and human factors as necessary to derive operational detection limits. These threshold detection values have been compared to existin… more

Date: August 1, 1991

Creator: Goles, R. W.; Baumann, B. L. & Johnson, M. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Harvard-MIT research program in short-lived radiopharmaceuticals

This report presents research on radiopharmaceuticals. The following topics are discussed: antibody labeling with positron-emitting radionuclides; antibody modification for radioimmune imaging; labeling antibodies; evaluation of technetium acetlyacetonates as potential cerebral blood flow agents; and studies in technetium chemistry. (CBS)

Date: January 1, 1991

Creator: Adelstein, S.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Calculation of /sup 59/Co neutron cross sections between 3 and 50 MeV

Knowledge of the /sup 59/Co(n,p), (n,..cap alpha..), and (n,xn) cross sections up to 50 MeV are necessary to satisfy priority dosimetry data needs of the FMIT facility. Since experimental data extend only to 25 MeV in the case of (n,xn) reactions (and lower energies for the others), these cross sections as well as those from competing reactions were calculated for neutron energies between 3 and 50 MeV. Neutron optical parameters were determined that were valid from several hundreds of keV to 50… more

Date: January 1, 1980

Creator: Arthur, E. D.; Young, P. G. & Matthes, W. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Influence of humic-acid complexing on the mobility of Americium in the soil aquatic environment

Diffusion data indicate the Am, Cm and Np migrate 1.2, 0.8, and 26 centimeters, respectively, in a thousand years. Thus, excluding mass transport by moving water or wind, actinide elements, such as Cm, Am, and Np that find their way to the soil-aquatic environment are relatively immobile. Measured diffusion coefficients, corrected for distribution between the aqueous and soil phases, tortuosity, negative absorption, and relative fluidity are in reasonable agreement with aqueous diffusion coeffi… more

Date: March 1, 1982

Creator: Sheppard, J.C.; Campbell, M.J. & Kittrick, J.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Experimental nuclear and radiochemistry. Progress report, February 1, 1979-January 31, 1980. [Dept. of Chemistry, Carnegie-Mellon Univ. , Pittsburgh, Pennsylvania, 2/1/79 to 1/31/80]

This project entails the investigation of deep nuclear spallation reactions induced by high-energy light particles on complex nuclei. Experimental studies involve activation of various medium- to heavy-mass targets bombarded by pi mesons, protons, and alpha particles. A prime objective is to deconvolve the cascade and evaporation steps in the reaction mechanism. Experimentally, then, particular emphasis has been placed on spallation products far from yield maxima. Irradiations have been perform… more

Date: January 1, 1980

Creator: Karol, P. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fast neutron capture cross sections of /sup 169/Tm, /sup 191/Ir, /sup 193/Ir, and /sup 175/Lu for 3 less than or equal to E/sub n/ less than or equal to 2000 keV

Fast neutron capture cross sections of /sup 169/Tm, /sup 191/Ir, /sup 193/Ir, and /sup 175/Lu, and the /sup 6/Li(n,..cap alpha..)/sup 3/H cross sections to which they are normalized are presented in tabular form for neutron energies between 3 and 2000 keV.

Date: November 1, 1977

Creator: Macklin, R.L.; Drake, D.M. & Malanify, J.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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/sup 18/F-4-fluoroantipyrine

The novel radioactive compound /sup 18/F-4-fluoroantipyrine having high specific activity which can be used in nuclear medicine in diagnostic applications, prepared by the direct fluorination of antipyrine in acetic acid with radioactive fluorine at room temperature and purifying said radioactive compound by means of gel chromatography with ethyl acetate as eluent is disclosed. The non-radioactive 4-fluoroantipyrine can also be prepared by the direct fluorination of antipyrine in acetic acid wi… more

Date: January 1, 1980

Creator: Shiue, Chyng-Ysnn & Wolf, Alfred P.

Item Type: Patent

Partner: UNT Libraries Government Documents Department

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(p,n) reaction at intermediate energy. [100 to 200 MeV]

The use of the (p,n) reaction in exploring effective interactions is reviewed. Some recent data on self-conjugate nuclei taken at the Indiana University Cyclotron Facility (IUCF) are presented, and the differences between low- and high-energy data are emphasized. Experimental problems and techniques used are briefly described. It is concluded that forward-angle (p,n) spectra at energies greater than 100 MeV are dominated by Gamow-Teller (GT) transitions, while Fermi transitions (IAS transitions… more

Date: January 1, 1979

Creator: Goodman, C. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status report on LWR spent fuel IAEA leach tests

Spent light-water-reactor (LWR) fuel with an average burnup of 28,000 MWd/MTU was leach-tested at 25/sup 0/C using a modified version of the International Atomic Energy Agency procedure. Leach rates were determined from tests conducted in five different solutions: deionized water, sodium chloride (NaCl), sodium bicarbonate (NaHCO/sub 3/), calcium chloride (CaCl/sub 2/) and Waste Isolation Pilot Plant B brine solutions. Elemental leach rates are reported based on the release of /sup 90/Sr + /sup… more

Date: March 1, 1980

Creator: Katayama, Y.B.; Bradley, D.J. & Harvey, C.O.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Silver isotopic anomalies in iron meteorites: cosmic-ray production and other possible sources

The sources of excess /sup 107/Ag observed in iron meteorites by Kaiser, Kelly, and Wasserburg (1980) are examined, with emphasis on the reactions of cosmic-ray particles with palladium. The cross sections for the production of the silver isotopes from palladium by energetic cosmic-ray particles are evaluated or estimated and used to calculate spallogenic production rates relative to that of /sup 53/Mn from iron. The upper limit for the production rate of excess /sup 107/Ag by galactic-cosmic-r… more

Date: April 18, 1980

Creator: Reedy, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department