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

Description: Extensive data analysis and theoretical analysis has been done to complete the extensive decay scheme investigation of /sup 206/ /sup 208/Fr and the level structures of /sup 206/ /sup 208/Rn. A final version of a journal article is presented in preprint form. Extensive Monte Carlo calculations have been made to correct the end point energies of positron spectra taken with intrinsic Ge detectors for annihilation radiation interferences. These calculations were tested using the decay of /sup 82/Sr which has previously measured positron branches. This technique was applied to the positron spectra collected at the on-line UNISOR isotope separator. The reactions used were /sup 60/Ni(/sup 20/Ne;p2n)/sup 77/Rb and /sup 60/Ni(/sup 20/Ne;pn)/sup 78/Rb. Values for 5, ..gamma..-..beta../sup +/ coincidence positron end point energies are given for the decay of /sup 77/Rb. The implied Q-value is 5.075 +- 0.010 MeV. A complete paper on the calculated corrections is presented. A flow chart of a more complete program which accounts for positrons scattering out of the detector and for bremsstralung radiation is also presented. End-point energies of four ..beta../sup +/ branches in /sup 77/Rb are given as well as a proposed energy level scheme of /sup 75/Kr based on ..gamma..-..gamma.. coincidence data taken at UNISOR.
Date: February 28, 1981
Creator: Avignone, F.T. III.
Partner: UNT Libraries Government Documents Department

Water quality monitoring report for the White Oak Creek Embayment

Description: Water quality monitoring activities that focused on the detection of resuspended sediments in the Clinch River were conducted in conjunction with the White Oak Creek Embayment (WOCE) time-critical Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to construct a sediment-retention structure at the mouth of White Oak Creek (WOC). Samples were collected by use of a 24-h composite sampler and through real-time water grab sampling of sediment plumes generated by the construction activities. Sampling stations were established both at the WOC mouth, immediately adjacent to the construction site, and at K-1513, the Oak Ridge K-25 Site drinking water intake approximately 9.6 km downstream in the Clinch River. Results are described.
Date: January 1, 1993
Creator: Ford, C.J. (Oak Ridge National Lab., TN (United States)) & Wefer, M.T. (Automated Sciences Group, Inc., Oak Ridge, TN (United States))
Partner: UNT Libraries Government Documents Department

Gamma-ray spectra from neutron capture on /sup 87/Sr

Description: The gamma-ray spectrum following neutron capture on /sup 87/Sr was measured at 3 neutron energies: E/sub n/ = thermal, 2 keV, and 24 keV. Gamma rays were detected in a three-crystal Ge(Li)-NaI-NaI pair spectrometer. Gamma-ray intensities deduced from these spectra by spectral unfolding are presented.
Date: July 1, 1981
Creator: Sullivan, R.E.; Becker, J.A. & Stelts, M.L.
Partner: UNT Libraries Government Documents Department

Geologic flow characterization using tracer techniques

Description: A new tracer flow-test system has been developed for in situ characterization of geologic formations. This report describes two sets of test equipment: one portable and one for testing in deep formations. Equations are derived for in situ detector calibration, raw data reduction, and flow logging. Data analysis techniques are presented for computing porosity and permeability in unconfined isotropic media, and porosity, permeability and fracture characteristics in media with confined or unconfined two-dimensional flow. The effects of tracer pulse spreading due to divergence, dispersion, and porous formations are also included.
Date: April 1, 1981
Creator: Klett, R. D.; Tyner, C. E. & Hertel, Jr., E. S.
Partner: UNT Libraries Government Documents Department

Experimental nuclear and radiochemistry. Progress report, February 1, 1980-January 31, 1981

Description: Deep nuclear spallation reactions induced by high-energy light particles on complex nuclei were investigated. 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. Emphasis has been placed on spallation products far from yield maxima where the deconvolution is most justifiable. Irradiations have been performed predominantly at the Clinton P. Anderson Los Alamos Meson Physics Facility. Results of cross section determinations from bombardments of /sup 89/Y, /sup 92/Mo, /sup 96/Mo and /sup 100/Mo with 800 MeV protons have nearly been completed, providing comparison of isobaric and mass-yield distributions. Data have also been obtained at 500 MeV. Theoretical efforts are being directed at the evaporative behavior of very high-temperature nuclei as determined by the nuclear equation of state and how such behavior might be observed in very deep spallation processes. In addition, the soft spheres model has been combined with spallation systematics to explore the feasibility of high-intensity beams to incinerate high-level nuclear wastes and also to predict interaction lengths in nuclear emulsion studies of relativistic heavy ions. Data are presented on spallation of /sup 130/Te by 800-MeV protons, decay of /sup 87/Zr, and /sup 84/Zr, spallation-transmutation of /sup 90/Sr, and anomalous relativistic projectile fragments in emulsion detectors. (DLC)
Date: November 1, 1980
Creator: Karol, P.J.
Partner: UNT Libraries Government Documents Department

Extension of the T /sub z/ = -3/2 series of beta-delayed proton precursors in the fp shell. [excitation energy, transition rates, log FT values, B strength, J,. pi. ]

Description: Beta-delayed proton studies of the T /sub z/ = -3/2, A = 4n+1 series were undertaken to obtain high resolution low background spectra of /sup 29/S and to extend the series into the fp shell with the observation of /sup 53/Ni, /sup 57/Zn, and /sup 61/Ge. Development of a pulsed-beam system in which large detection geometries were obtained was crucial in characterizing the latter nuclei due to low production cross sections (50 to 90 nb) for the /sup 40/Ca(heavy ion, 3n) reactions. Spectroscopic studies of the beta-delayed proton decay of /sup 29/S have yielded branching ratios and log ft values for 21 proton unbound levels in /sup 29/P. Comparisons of excitation energies of these levels and ..beta..-decay transition rates feeding them are made to recent shell model predictions. Indications of possible isospin mixing with the lowest T = 3/2 state in /sup 29/P or the presence of a collective Gamow-Teller transition as predicted by the gross theory of ..beta..-decay are indicated by enhanced transition rates to T = 1/2 states located within 300 keV of the isobaric analog state. Comparing the ft values for ..beta../sup +/-decay of /sup 29/S to the mirror ..beta../sup -/-decay of /sup 29/Al resulted in (ft)/sup +//(ft)/sup -/ = 1.04+-0.07, indicating good mirror symmetry. Exploiting the unique signature of delayed proton emission, the decays of several nuclei in the unknown neutron-deficient region of the fp shell were characterized.The following precursors and delayed proton groups were observed. /sup 53/Ni - Ep(c.m.) = 1.94+-.05 MeV, T1/2 = 45+-15 ms; /sup 57/Zn - Ep(c.m.) = 1.95+-.05, 2.58+-.05, and 4.65+-.05 MeV, T1/2 = 40+-10 ms; /sup 61/Ge - Ep(c.m.) = 3.15+-.07 MeV, T1/2 = 40+-15 ms. All of these proton groups (except the 2.58 MeV group of /sup 57/Zn) are attributed to the decay of the lowest T = 3/2 ...
Date: December 1, 1978
Creator: Vieira, D.J.
Partner: UNT Libraries Government Documents Department

Distribution coefficient data and preliminary estimates of movement of radionuclides, Tatum salt dome, Lamar County, Mississippi. Technical letter: Dribble 31

Description: Estimates are made relating radionuclide movement to ground water velocity as part of the safety program for a proposed experiment to detonate nuclear devices within the Tatum salt dome. The estimates are based on distribution coefficients obtained from laboratory studies. Core samples obtained from hydrologic test well HT-3, Tatum salt dome, Lamar County, Mississippi, were equilibrated with radionuclides in solutions simulating aquifer waters found in the area. The combinations of Cenozoic sand and silty clay, and quality of water of the area were studied and summarized. The distribution coefficients obtained for different radionuclides were tested and indicate retardation factors from 1.3 to 857 for the travel time of these radionuclides when compared to the travel time of water in the aquifer system. Laboratory results indicate that migration of any radioisotope inadvertently introduced to the aquifers in the vicinity of the dome as a result of proposed nuclear test explosions would be extremely slow. Revised estimates of the rate of dissolved radioisotope movement will be made on the basis of further laboratory studies utilizing chromatographic adsorption columns of 0.5 to 4.0 feet in length.
Date: April 10, 1963
Creator: Beetem, W.A. & Janzer, V.J.
Partner: UNT Libraries Government Documents Department

Phase 1 data summary report for the Clinch River Remedial Investigation: Health risk and ecological risk screening assessment

Description: The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy's (DOE's) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. The purpose of this report is to summarize the results of Phase 1 of the CRRI. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels in fish, sediment, and water from the CR/WBR; (2) determine the in the range of contaminant concentrations present river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants.
Date: December 1, 1992
Creator: Cook, R.B.; Adams, S.M.; Beauchamp, J.J.; Bevelhimer, M.S.; Blaylock, B.G.; Brandt, C.C. et al.
Partner: UNT Libraries Government Documents Department

216-S-1 and S-2 mixed-fission-product crib-characterization study

Description: The 216-S-1 and 2 crib is an underground structure that was used for the disposal of radioactively contaminated liquid waste at the Hanford Site. The crib received acidic, intermediate level, mixed fission-product waste solutions from 1952 to 1956. The 1980 status of radioactive contaminants in the sediment beneath the crib was investigated. The results indicate that the radionuclide distributions are stable, with no evidence of significant translocations found since the late 1960's.
Date: March 1, 1982
Creator: Van Luik, A. E. & Smith, R. M.
Partner: UNT Libraries Government Documents Department

Hanford Environmental Dose Reconstruction Project

Description: The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation dose that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into five technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (i.e., dose estimates). The Source Terms Task develops estimates of radioactive emissions from Hanford facilities since 1944. The Environmental Transport Task reconstructs the movements of radioactive particles from the areas of release to populations. The Environmental Monitoring Data Task assemblies, evaluates and reports historical environmental monitoring data. The Demographics, Agriculture and Food Habits Task develops the data needed to identify the populations that could have been affected by the releases. The Environmental Pathways and Dose Estimates Task used the information derived from the other Tasks to estimate the radiation doses individuals could have received from Hanford radiation. This document lists the progress on this project as of September 1991. 3 figs., 2 tabs.
Date: September 1, 1991
Partner: UNT Libraries Government Documents Department

Waste minimization for commercial radioactive materials users generating low-level radioactive waste

Description: The objective of this document is to provide a resource for all states and compact regions interested in promoting the minimization of low-level radioactive waste (LLW). This project was initiated by the Commonwealth of Massachusetts, and Massachusetts waste streams have been used as examples; however, the methods of analysis presented here are applicable to similar waste streams generated elsewhere. This document is a guide for states/compact regions to use in developing a system to evaluate and prioritize various waste minimization techniques in order to encourage individual radioactive materials users (LLW generators) to consider these techniques in their own independent evaluations. This review discusses the application of specific waste minimization techniques to waste streams characteristic of three categories of radioactive materials users: (1) industrial operations using radioactive materials in the manufacture of commercial products, (2) health care institutions, including hospitals and clinics, and (3) educational and research institutions. Massachusetts waste stream characterization data from key radioactive materials users in each category are used to illustrate the applicability of various minimization techniques. The utility group is not included because extensive information specific to this category of LLW generators is available in the literature.
Date: July 1, 1991
Creator: Fischer, D.K.; Gitt, M.; Williams, G.A.; Branch, S. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Otis, M.D.; McKenzie-Carter, M.A. et al.
Partner: UNT Libraries Government Documents Department

Mechanism and kinetics of mineral absorption by plants. Annual progress report, October 1, 1965-September 30, 1966

Description: Plant nutrition was studied as a relation between aerobic respiration and ion uptake in barley. Potassium, chlorine, lithium, sodium, calcium, sulfates, and bicarbonates were studied by root absorption in varying concentrations of carbon dioxide atmospheres. (PSB)
Date: January 1, 1966
Creator: Jacobson, L. & Overstreet, R.
Partner: UNT Libraries Government Documents Department

Measurement of Leaching From Simulated Nuclear-Waste Glass Using Radiotracers

Description: The use of radiotracer spiking as a method of measuring the leaching from simulated nuclear-waste glass is shown to give results comparable with other analytical detection methods. The leaching behavior of /sup 85/Sr, /sup 106/Ru, /sup 133/Ba, /sup 137/Cs, /sup 141/Ce, /sup 152/Eu, and other isotopes is measured for several defense waste glasses. These tests show that radiotracer spiking is a sensitive, multielement technique that can provide leaching data, for actual waste elements, that are difficult to obtain by other methods. Additionally, a detailed procedure is described that allows spiked glass to be prepared with a suitable distribution of radionuclides.
Date: September 1982
Creator: Bates, J. K.; Jardine, L. J. & Steindler, M. J.
Partner: UNT Libraries Government Documents Department

Study of proton hole states in 1f/sub 7/2/ nuclei by the (p,2p) reaction at 46 MeV

Description: Proton hole states in the 1f/sub 7/2/ nuclei /sup 46/Ti, /sup 54/Fe, /sup 56/Fe, /sup 58/Ni, and /sup 60/Ni have been studied with the (p,2p) reaction with 46-MeV protons. The measured binding energies and angular correlations are consistent with the binding energies and orbital angular momentum assignments (1f/sub 7/2/, 2s/sub 1/2/, and 1d/sub 3/2/) obtained from proton pick-up reactions. 3 figures, 1 table.
Date: March 1, 1970
Creator: Bertrand, F.; Eisberg, R.; Ingham, D.; Makino, M. & Waddell, C.
Partner: UNT Libraries Government Documents Department

Technical Division quarterly progress report, April 1--June 30, 1978

Description: Fuel cycle research and development: results are presented on fluidized-bed calcination and on post-treatment of commercial wastes; study was done on the use of microwave energy in processing wastes and on the use of bidentate compounds for separation of actinides from commercial power reactor reprocessing waste. Work on the krypton-85 storage development program, including the results of rubidium corrosion tests, is reported. In the HTGR fuel reprocessing section, the results of x-ray and Auger spectroscopy analysis of CO oxidation catalyst are reported. Special materials production: the long-term management of high-level ICPP wastes is reported: development of a calcine pelletizing pilot plant, actinide removal, actinide extraction by DHDECMP, and calcined solids retrieval and handling. Design work was completed for the fluorinel pilot-plant upgrade. Other development results reported are on the progress of the Rover plant, and on flowsheet development for electrolytic and second-cycle waste, for Fluorinel waste, and for Tank WM-183. Other results reported include: assistance to the Waste Calcining Facility and to the New Waste Calcining Facility, methods for the monitoring of gaseous effluents, and a mathematical model to describe chloride buildup in the waste calcining scrubbing solution. Other projects supporting energy developments: results are reported on nuclear materials safety, the installation and operation of a geothermal fluidized-bed dryer, the in-plant source-term measurement at the Turkey Point station, burnup methods for fast breeder reactor fuels, absolute thermal fission yields, analytical support to light-water breeder reactor developments, cerium analysis of actinide removal project solutions, a spark source mass spectrometric computer program, and on environmental iodine species behavior.
Date: December 1, 1978
Creator: Plung, D.L. (ed.)
Partner: UNT Libraries Government Documents Department

Technical Division quarterly progress report, January 1--March 31, 1978

Description: Fuel Cycle Research and Development: Results are presented on the fluidized-bed calcination of simulated waste from the reprocessing of spent commercial nuclear fuel, on the post-treatment of the resultant calcine, and on the use of bidentate extractants for the separation of actinide elements from the high-level waste prior to calcination. In addition, the development of storage technology for krypton-85 waste, and the behavior of RuO/sub 2/ in fluidized-bed combustion of HTGR fuel are reported. Special Materials Production: Reported are the long-term management of defense waste from the ICPP, the chemistry and pilot plant-studies on the removal of actinides and mercury from ICPP first cycle raffinate, the calcined solids retrieval and handling of ICPP waste stored in vaults, and the preparation of environmental impact statements on options given the Defense Waste Document. Process improvements are given on the Fluorinel headend process for zircaloy-clad fuel and on methods for uranium accountability. Other development results reported are on the Rover process for graphite based fuels, on the calcination of sodium-bearing waste, Fluorinel waste, tank WM-183 waste, and electrolytic process waste. Assistance to the Waste Calcination Process Plant is reported as well as support to the New Waste Calcination Process and methods for the monitoring of gaseous effluents. Other Projects Supporting Energy Developments: Results are reported on nuclear materials security, the behavior of liquid-solid fluidized-bed heat exchangers, in-plant reactor source term measurements, burnup methods for fast breeder reactor fuels, absolute thermal fission yields, analytical support to light water breeder reactor development, and species of iodine in the environment. Research on analytical methods cover iodine-129 in calciner feed, computing room improvements, stack gas sampling for particulates, analysis of glassified calcined waste, and specific components in various materials.
Date: July 1, 1978
Creator: Slansky, C.M. (ed.)
Partner: UNT Libraries Government Documents Department

Summary statement of findings related to the distribution, characteristics, and biological availability of fallout debris originating from testing programs at the Nevada Test Site

Description: Summary statements are given of significant findings related to the distribution, characteristics, and biological availability of fall-out debris originating from testing programs at the Nevada Test Site during the past decade. The delineation of fall-out patterns has been accomplished by the use of aerial and ground monitoring surveys. Only about 25% of the total amount of fission products produced by tower-supported detonations were deposited within distances corresponding to fall-out time of H + 12 hr; a much smaller quantity was deposited by balloon-supported detonations. Most of the fall-out debris that was redistributed by various environmental factors after original deposition consisted of particles < 44 ..mu.. in diameter; the particles in this size range also represented the predominant contamination on plant foliage. /sup 90/Si levels in surface soil ranged from 31.9 to 142 mc/sq mile in virgin areas near known fall-out pattern midlines and from 7.5 to 22.7 mc/sq mile in agricultural areas that in some cases did not coincide with fall-out pattern midlines. The accumulation of radioiodine by native animals was observed to be a function of distance from GZ. /sup 140/Ba, /sup 91/Y, /sup 89/Sr and /sup 90/Sr were major bone contaminants. Post-series sampling of native animals indicated that the accumulation by animals correlated poorly with the strontium unit levels in soils. The strontium unit levels increased in milk immediately following contamination of the farm with fall-out dehbris and then decreased with time as well as the amount of strontium associated with the cattle's diet. Observations during the past decade indicate that less than 10% of the total strontium produced from nuclear detonations at NTS has been deposited within 200 miles from the point of detonation.
Date: September 14, 1960
Creator: Larson, K.H. & Neel, J.W.
Partner: UNT Libraries Government Documents Department

Inhaled /sup 239/PuO/sub 2/ and/or total-body gamma radiation: Early mortality and morbidity in rats and dogs

Description: Rats and beagle dogs were given doses of /sup 60/Co gamma radiation and/or body burdens of /sup 239/PuO/sub 2/ within lethal ranges in an experiment to determine and compare morbidity and mortality responses of both species within 1 year after exposure. Radiation-induced morbidity was assessed by measuring changes in body weights, hematologic parameters, and pulmonary-function parameters. Gamma radiation caused transient morbidity, reflected by immediately depressed blood cell concentrations and by long-term loss of body weight and diminished pulmonary function in animals of both species that survived the acute gamma radiation syndrome. Inhaled plutonium caused a loss of body weight and diminished pulmonary function in both species, but its only effect on blood cell concentrations was lymphocytopenia in dogs. Combined gamma irradiation and plutonium lung burdens were synergistic, in that animals receiving both radiation insults had higher morbidity and mortality rates than would be predicted based on the effect of either kind of radiation alone. Plutonium lung burdens enhanced the effect of gamma radiation in rats within the first 30 days of exposure, and gamma radiation enhanced the long-term effect of plutonium lung burdens in both species. Rats were less sensitive to both kinds of radiation, whether administered alone or in combination. 71 refs., 105 figs., 48 tabs.
Date: August 1, 1988
Creator: Filipy, R.E.; Decker, J.R.; Lai, Y.L.; Lauhala, K.E.; Buschbom, R.L.; Hiastala, M.P. et al.
Partner: UNT Libraries Government Documents Department

Iodine-129: a review of its potential impact on the environment

Description: Attention has been drawn to /sup 129/I, a radionuclide with a long half-life and the potential for long-term accumulation in the environment as a result of low-level, chronic releases from nuclear facilities such as nuclear fuel reprocessing plants. The metabolic and physiologic data on iodine, as well as the currently accepted metabolic models, are summarized. In addition, projections of iodine-129 production and release, as well as estimates of the potential hazards derived by various authors, are presented and discussed. The implications of these considerations on the deep geologic disposal of /sup 129/I are reviewed and summarized. At this time there are limited data available to assess in detail the impact of releases of /sup 129/I to the environment from a geologic waste repository. Since this isotope is essentially stable (has a low specific activity because of its long radioactive half-life) it has been generally regarded as not contributing significantly to the total population dose commitment. Therefore, the presence of this isotope in a waste repository should not significantly affect repository design and operation. However, additional research in several areas such as the movement of /sup 129/I from a repository to the surface by ground water and the influence on uptake fraction of the incorporation of /sup 129/I in foodstuffs would be useful to more accurately quantify environmental effects.
Date: May 1, 1978
Creator: Poston, J.W.
Partner: UNT Libraries Government Documents Department

Use of extractive distillation to produce concentrated nitric acid

Description: Concentrated nitric acid (> 95 wt %) is needed for the treatment of off-gases from a fuels-reprocessing plant. The production of concentrated nitric acid by means of extractive distillation in the two-pot apparatus was studied to determine the steady-state behavior of the system. Four parameters, EDP volume (V/sub EDP/) and temperature (T/sub EDP/), acid feed rate, and solvent recycle, were independently varied. The major response factors were percent recovery (CPRR) and product purity (CCP). Stage efficiencies also provided information about the system response. Correlations developed for the response parameters are: CPRR = 0.02(V/sub EDP/ - 800 cc) + 53.5; CCP = -0.87 (T/sub EDP/ - 140/sup 0/C) + 81; eta/sub V,EDP/ = 9.1(F/sub feed/ - 11.5 cc/min) - 0.047(V/sub EDP/ - 800 cc) - 2.8(F/sub Mg(NO/sub 3/)/sub 2// - 50 cc/min) + 390; and eta/sub L,EDP/ = 1.9(T/sub EDP/ - 140/sup 0/C) + 79. A computer simulation of the process capable of predicting steady-state conditions was developed, but it requires further work.
Date: April 1, 1981
Creator: Campbell, P.C.; Griffin, T.P. & Irwin, C.F.
Partner: UNT Libraries Government Documents Department

Harvard--MIT research program in short-lived radiopharmaceuticals. Progress report, September 1, 1977--April 30, 1978. [/sup 99m/Tc, positron-emitting radionuclides]

Description: Progress is reported on the following studies: chemistry studies designed to achieve a more complete understanding of the fundamental chemistry of technetium in order to facilitate the design of future radiopharmaceuticals incorporating the radionuclide /sup 99m/Tc; the development of new radiopharmaceuticals intended to improve image quality and lower radiation doses by the use of short-lived radionuclides and disease-specific agents; the development of short-lived positron-emitting radionuclides which offer advantages in transverse section imaging of regional physiological processes; and studies of the toxic effects of particulate radiation.
Date: May 1, 1978
Creator: Adelstein, S.J. & Brownell, G.L.
Partner: UNT Libraries Government Documents Department

Avian radioecology on a nuclear power station site. Final report

Description: A summary of a six-year avian radioecology study at the site of a nuclear power plant in Massachusetts is reported. A completed historical summary is followed by a description of mathematical models developed to calculate the effects on bird body burdens of various changes in environmental radionuclide levels. Examples are presented. Radionuclide metabolism studies in which acute doses of /sup 131/I and /sup 137/Cs were administered to four species of wild birds are presented. Radionuclides were administered both intravenously and orally; no apparent differences in uptake or elimination rates were observed between the two methods.
Date: January 1, 1975
Creator: Levy, C.K.; Maletskos, C.J. & Youngstrom, K.A.
Partner: UNT Libraries Government Documents Department

Beta-delayed proton activities: /sup 147/Dy and /sup 149/Er

Description: The present paper discusses mainly the ..beta..-delayed proton spectra of /sup 147/Dy and of the hitherto unknown isotope, /sup 149/Er. However, following the submittal of the abstract for this conference we have now observed delayed protons following the decay of /sup 145/Dy. Additionally, we have identified a 0.5-s delayed-proton emitter and tentatively assign it to the new isotope, /sup 151/Yb.
Date: January 1, 1984
Creator: Toth, K.S.; Moltz, D.M.; Schloemer, E.C.; Cable, M.D.; Avignone, F.T. III & Ellis-Akovali, Y.A.
Partner: UNT Libraries Government Documents Department

Ceramic phases for immobilization of /sup 129/I. [Sodalite and boracite]

Description: Materials for ultimate disposal of /sup 129/I have been studied. At present, iodide-sodalite, though not ideal, appears to be the best material for /sup 129/I immobilization from the aspects of ease of preparation, thermal stability, cost of materials, and leach resistance. Good consolidation of the material was achieved by sintering in air at 1000 to 1200/sup 0/C, but the iodine content was significantly below stoichiometric expectations. Hot aqueous media preferentially removed iodine, apparently by OH/sup -/ substitution in near-neutral solutions, and I reversible reaction Cl/sup -/ exchange occurred in brine. Alternation of the sodalite also took place. Soxhlet leach rates were about 5 x 10/sup -4/ g/cm/sup 2/-day by total weight loss, but physical weathering contributed significantly to this value. Moderate doses of radiation had no observable deleterious structural effects. Iodoboracites seemingly cannot be prepared by ceramic or nonhydrothermal wet chemical techniques. Fe-iodoboracite has inferior thermal stability to iodide-sodalite and was completely altered to hematite after treatment at 200/sup 0/C in deionized water. Silver zeolites retained some iodine in the form of crystalline ..cap alpha..-AgI at temperatures up to 1300/sup 0/C even though heating above approx. 700/sup 0/C altered the alumino-silicate framework. However, some of the iodine appeared to be present as soluble iodine, even in heated materials. Treatment at 200/sup 0/C in deionized water or 2M NaCl significantly decreased the crystallinity of the aluminosilicate framework and the ..cap alpha..-AgI reflections in the x-ray patterns were enhanced. Mild ..gamma.. irradiations (approx. 50 MR) affected the x-ray diffraction patterns of some of the zeolites. Various lead oxyhalides had very poor thermal stability.
Date: July 31, 1981
Creator: Vance, E.R.; Agrawal, D.K.; Scheetz, B.E.; Pepin, J.G.; Atkinson, S.D. & White, W.B.
Partner: UNT Libraries Government Documents Department