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Measurement of radionuclides using ion chromatography and flow-call scintillation counting with pulse shape discrimination: Topical report, September 15, 1996--October 3, 1996, Tasks 1.11, 1.12 and 1.13

Description: Several flow-cell radiation detector systems are commercially available for quantification of aqueous radioactive solutions. These systems do not use the technique of pulse shape discrimination to identify the incident radiation and therefore are limited in environmental characterization application when coupled to an ion chromatography system. The advantages of the pulse shape discriminating flow-cell detector over the commercially available systems include: (1) lower minimum detectable activity for alpha radiation, (2) reduced radiological interferences that may exist between co-eluted alpha- and beta-emitting radionuclides, and (3) possible isotopic information from the ion chromatography system. For Tasks 1.1.1 and 1.1.2 of this project, several scintillation materials were investigated for pulse shape (alpha and beta) discrimination capabilities and the best candidate material was optimized. In addition, the following detector properties were also optimized: scintillator particle size, flow-cell tubing type, and electromagnetic as well as optical crosstalk between the photomultiplier tubes.
Date: April 1, 1997
Partner: UNT Libraries Government Documents Department

Direct measurement of strontium-90 and uranium-238 in soils on a real-time basis: 1994 summary report

Description: Traditional methodologies for quantitative characterization of radionuclide-contaminated soils over extended areas are often tedious, costly, and non-representative. A rapid characterization methodology was designed that provides reliable output with spatial resolution on the order of a few meters or less. It incorporates an innovative sensor of square plastic scintillating fibers that has been designed to be placed directly on or above a contaminated soil to detect and quantify high-energy beta particles associated with the decay chains of uranium and/or strontium. Under the direction and auspices of the DOE`s Characterization, Monitoring, and Sensor Technology Integrated Program, Pacific Northwest Laboratory (PNL) constructed a high-energy beta scintillation sensor that was optimized for the detection and quantification of uranium and strontium contamination in surface soils (in the presence of potentially interfering natural and anthropogenic radionuclides), demonstrated and evaluated this detector in various field and laboratory scenarios, and provides this document in completion of the aforementioned requirements.
Date: April 1, 1995
Creator: Schilk, A.J.; Hubbard, C.W.; Knopf, M.A. & Thompson, R.C.
Partner: UNT Libraries Government Documents Department

HALF-LIVES OF LONG-LIVED A-DECAY, B-DECAY, BB-DECAY AND SPONTANEOUS FISSION NUCLIDES.

Description: In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for a discussion session at the next meeting. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay and spontaneous fission decay. This report is preliminary but will provide a quick overview of the extensive table of data on the recommendations from that review.
Date: June 29, 2001
Creator: HOLDEN,N.E.
Partner: UNT Libraries Government Documents Department

Hanford high level waste: Sample Exchange/Evaluation (SEE) Program

Description: The Pacific Northwest Laboratory (PNL)/Analytical Chemistry Laboratory (ACL) and the Westinghouse Hanford Company (WHC)/Process Analytical Laboratory (PAL) provide analytical support services to various environmental restoration and waste management projects/programs at Hanford. In response to a US Department of Energy -- Richland Field Office (DOE-RL) audit, which questioned the comparability of analytical methods employed at each laboratory, the Sample Exchange/Exchange (SEE) program was initiated. The SEE Program is a selfassessment program designed to compare analytical methods of the PAL and ACL laboratories using sitespecific waste material. The SEE program is managed by a collaborative, the Quality Assurance Triad (Triad). Triad membership is made up of representatives from the WHC/PAL, PNL/ACL, and WHC Hanford Analytical Services Management (HASM) organizations. The Triad works together to design/evaluate/implement each phase of the SEE Program.
Date: August 1, 1994
Creator: King, A.G.
Partner: UNT Libraries Government Documents Department

1987 Oak Ridge model conference: Proceedings: Volume I, Part 2, Waste Management

Description: A conference sponsored by the United States Department of Energy (DOE) was held on Waste Mangement. Topics discussed were waste stabilization technologies regulations and standards, innovative treatment technology, waste stabilization projects. Individual projects are processed separately for the data bases. (CBS)
Date: January 1, 1987
Partner: UNT Libraries Government Documents Department

Cobalt-60 heat source demonstration program. Phase III. Fabrication. Final report

Description: Significant accomplishments completed during Phase III of the /sup 60/Co Heat Source Demonstration program include the following: encapsulation of 2 MCi of /sup 60/Co; fabrication of the heat source, including the ASME coded pressure vessel/core assembly, and biological shielding; endurance testing of a prototype heat pipe for a period of 28 months; fabrication and qualification of the heat pipe emergency cooling subsystem; issue of the safety evaluation report, reference 3, and the operations manual, reference 4; and heat source assembly. The planned demonstration test program was modified to include testing of a total power system. Based on an evaluation of available power conversion systems, which included the closed-cycle Brayton and organic Rankine systems, the closed-cycle Brayton system was selected for use. Selection was based on advantages offered by the direct coupling of this conversion system with the gas-cooled heat source. In implementing the test program, the AiResearch BCD power conversion system was to be coupled to the heat source following initial heat source performance testing and part way through the endurance test. In accordance with the program redirection the following Phase IV checkout operations were completed to evaluate procedural and hardware acceptability: heat source dummy fueling; fueling cask sielding survey; and heat source shielding survey (single pin). Completion of these latter activities verified the acceptability of critical characteristics of the heat source and its supporting equipment.
Date: June 1, 1973
Partner: UNT Libraries Government Documents Department

Tritium waste control, October--December 1977. [Tritiated liquid waste decontamination; fixation of aqueous tritiated waste in polymer-impregnated concrete]

Description: The combined electrolysis-catalytic-exchange pilot scale system was operated on a 5 hr/day basis for 32 days without a major equipment failure. Modifications were made to the Nd:YAG laser that increased the output power by five. The increased beam quality and power of the laser allowed optical parametric oscillator (OPO) operation over a 2.9 to 4.14 ..mu..m tuning range. Background exchange was eliminated in the photolysis system and photolytic experiments were commenced. Photo dissociation experiments with H/sub 2/O/D/sub 2/ revealed that the xenon flashlamp should have sufficient spectral emittance in the less than or equal to 194 nm region to produce detectable amounts of photodissociation in vibrationally excited HDO. The short 10 cm long x 0.6 cm i.d. column was replaced by a 50-cm-long column of the same diameter. A thermometer was placed at the midpoint of the column to assist in the analysis of column operation. A new liquid level probe was installed. Tests of stage height were repeated with the longer column. Triplicate samples of cement, cement-plaster (1:1 ratio by weight), and cement-plaster (1:1 ratio by volume) were injected with 386 Ci of tritium, cured for five days, and then impregnated with catalyzed styrene monomer. After polymerization, the samples were put into a test program to measure the tritium release. When the polystyrene bottle was removed the tritium release increased fiftyfold. This corresponds to a fractional release of 2.8 x 10/sup -1/ after 31 weeks. The tritium release study of actual burial packages is continuing. Two additional drums have just been added to the study. These contain octane waste. The fractional release is 1 x 10/sup -5/ on a 5-yr old package, only 4.0 x 10/sup -7/ on a 4-yr old package, and 4.7 x 10/sup -9/ on the 2-yr old package.
Date: March 4, 1978
Partner: UNT Libraries Government Documents Department

Tritium diffusion in nonmetallic solids of interest for fusion reactors. Final report

Description: Tritium diffusion measurements have been conducted in Al/sub 2/O/sub 3/, BeO, Y/sub 2/O/sub 3/, SiC, B/sub 4/C, Si/sub 3/N/sub 4/ and pyrolytic carbon as a basis for evaluating these materials as potential tritium barriers in fusion reactors. Deuterium solubility measurements were conducted with Al/sub 2/O/sub 3/, SiC and pyrolytic carbon to establish the pressure and temperature dependence of solubility and to identify solubility ranges. Hydrogen permeability measurements on commercially available Al/sub 2/O/sub 3/ and SiC materials were used as a check on calculated permeabilities and to provide data on hydrogen permeation rates in polycrystalline materials. The diffusion, solubility and permeation results are presented and discussed in terms of fusion reactor applications.
Date: January 1, 1979
Creator: Elleman, T
Partner: UNT Libraries Government Documents Department

Supralinearity of peak 5 and peak 6 in TLD-700

Description: Track Theory has been applied to an earlier suggestion, that the supralinearity of TLD's at high gamma-ray doses is due to pre-existing 1-hit and 2-hit trap structures, to calculate high-LET response. Measured /sup 60/Co responses for peaks 5 and 6 in LiF(TLD-700) were decomposed to yield parameters characterizing each peak as a 2-component c-hit mixture. One value of trap radius was assigned to each 2-component representation, different for peak 5 and for peak 6, to calculate their responses for H, He, C, O, and Ne bombardments. Calculations reproduce experimental features of the heavy-ion response of TLD-700, and provide means of connecting the gamma and high-LET responses in thermoluminescent dosimeters.
Date: January 1, 1980
Creator: Waligorski, M P.R. & Katz, R
Partner: UNT Libraries Government Documents Department

Studies in iodine metabolism. Progress report and publications, 1979-1980

Description: Research programs for the years 1978-1980 is reported. The following subject areas are discussed: (1) iodine 131 monitoring in thyroids of sheep, cattle and humans; (2) radium monitoring in cattle thyroids; (3) the relationship of thyroid function to seizures in rats; (4) the effect of KSCN on thyroglobulin in mice; and (5) studies on excessive iodide intake. (ACR)
Date: January 1, 1980
Creator: Van Middlesworth, L
Partner: UNT Libraries Government Documents Department

Environmental studies group. Annual report for 1978

Description: Group projects included radioecological studies of aquatic and terrestrial systems, land management activities, foodstuff monitoring, dust transport studies including fugitive dust measurements and modeling, and several support programs involving evaluation of the plant's ambient air samplers and airborne tritium monitoring techniques. Some salient results from the several project reports include determination of an appropriate model for mechanically generated fugitive dust dispersion, a radionuclide inventory of Smart Ditch Pond (Pond D-1), a coefficient of community determination for two terrestrial sample plots on the plant site buffer zone, a natality and mortality rate determination for fawns in the plant deer herd (including one positive coyote-kill determination), inlet loss and filter paper collection efficiencies for the plant ambient air samplers, and differential tritium sampling measurements of the vapor in Building 771 stack effluent.
Date: August 21, 1980
Creator: Hunt, D. C. & Hurley, J. D.
Partner: UNT Libraries Government Documents Department

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

Description: 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
Partner: UNT Libraries Government Documents Department

Actinide partitioning-transmutation program final report. VII. Long-term risk analysis of the geologic repository

Description: This report supports the overall assessment by Oak Ridge National Laboratory of actinide partitioning and transmutation by providing an analysis of the long-term risks associated with the terminal storage of wastes from a fuel cycle which incorporates partitioning and transmutation (P-T) and wastes from a cycle which does not. The system model and associated computer code, called AMRAW (Assessment Method for Radioactive Waste), are used for the analysis and are applied to the Los Medanos area in southeastern New Mexico. Because a conservative approach is used throughout, calculated results are believed to be consistently higher than reasonable expectations from actual disruptive incidents at the site and therefore are not directly suited for comparison with other analyses of the particular geologic location. The assessment is made with (1) the probabilistic, or risk, mode that uses combinations of reasonable possible release incidents with their probability of occurrence distributed and applied throughout the assessment period, and (2) the consequence mode that forces discrete release events to occur at specific times. An assessment period of 1 million years is used. The principal results are: (1) In all but the expulsive modes, /sup 99/Tc and /sup 129/I completely dominate cumulative effects based on their transport to man through leaching and movement with groundwater, effecting about 33,000 health effects (deaths) over the 1 million years; (2) P-T has only limited effectiveness in reducing long-term risk from a radionuclide waste repository under the conditions studied, and such effectiveness is essentially confined to the extremely unlikely (probability of occurrence 10/sup -12//year) expulsive events; (3) Removal or immobilization of /sup 99/Tc and /sup 129/I might provide benefits sufficiently tangible to warrant special consideration.
Date: September 1, 1980
Creator: Logan, S.E.; Conarty, R.L.; Ng, H.S.; Rahal, L.J. & Shirley, C.G.
Partner: UNT Libraries Government Documents Department

Nevada Test Site Radionuclide Inventory and Distribution Program: Report No. 2. Areas 2 and 4

Description: Radionuclide activity was measured by in situ spectrometry at 349 locations in Areas 2 and 4 of the Nevada Test Site. The data were analyzed by kriging and other methods to estimate the total inventory and distribution of six man-made radionuclides that were present in measurable amounts. Isotope ratios in soil samples were then used to infer the inventories of three other radionuclides. The estimated inventories were: /sup 241/Am, 8 curies; /sup 238/Pu, 18 curies; /sup 239,240/Pu, 51 curies; /sup 60/Co, 7 curies; /sup 137/Cs, 34 curies; /sup 90/Sr, 71 curies; /sup 152/Eu, 35 curies; /sup 154/Eu, 6 curies; and /sup 155/Eu, 3 curies.
Date: September 1, 1985
Creator: McArthur, R.D. & Kordas, J.F.
Partner: UNT Libraries Government Documents Department

Metabolism of /sup 90/Sr and other elements in man, April 1, 1976--March 31, 1977 (extended without additional funding to March 31, 1978) and renewal proposal, April 1, 1978--March 31, 1979

Description: Trace element studies of cadmium, copper, zinc, lead, manganese, and nickel were carried out under strictly controlled dietary conditions in adult males during different calcium intakes. Complete metabolic balances of the trace elements listed above were determined in each 6-day metabolic period for several weeks by analyzing the constant diet and the urinary and fecal excretions of these naturally occurring elements, using atomic absorption spectroscopy. Strontium-90 metabolism studies in man were carried out in order to complete previously initiated investigations. Publications and presentations of papers derived from studies carried out during the current contract period are listed.
Date: January 1, 1977
Creator: Spencer, H.
Partner: UNT Libraries Government Documents Department

Mechanistic studies of catalytic methanol synthesis. Final report

Description: The catalytic methanol production on a Cu-Zn-oxide catalyst was studied at 17 atm and about 200 C in a batch reactor. The initial rate measurement was performed for different CO/sub 2//CO ratios in the feed. The rate was found to increase with increasing CO/sub 2//CO, for a fixed H/sub 2/ partial pressure. This behavior was observed for catalysts at different stages of deactivation, and from 195 to 225 C. Addition of a small amount of water vapor greatly suppressed the rate. When C/sup 18/O/sub 2/ was used in a feed of CO/sub 2/:CO:H/sub 2/ = 3:10:20, the initial rate of production of methanol-/sup 18/O was found to be about half the rate of production of methanol-/sup 16/O. In view of the much lower partial pressure of CO/sub 2/ than CO in the feed, this result suggests that the hydrogenation rate of CO/sub 2/ on a per mole basis is faster than that of CO. This is consistent with the above initial rate data. Production of C/sup 16/O/sup 18/O and C/sup 16/O/sub 2/ were also rapid, which indicated rapid exchange of the lattice oxygen with CO/sub 2/. The production of H/sub 2//sup 18/O was also rapid, being about twice as fast as the methanol production rate. Thus under the conditions of initial rate measurements, the water-gas shift reaction is rapid. The relative rates of hydrogenation of CO/sub 2/ and CO were also determined near chemical equilibrium by the relaxation method. Nonequilibrium thermodynamic theories were applied to describe the relaxation process. The physical meaning of the equilibrium exchange rate for a complex reaction was discovered. A method was developed to mesure the equilibrium exchange rates of the simultaneous reactions in methanol synthesis. 18 references, 4 figures, 3 tables.
Date: March 1, 1984
Creator: Kung, H. H.
Partner: UNT Libraries Government Documents Department

Fabrication of three 2500-watt (thermal) strontium-90 heat sources

Description: Three 2500-watt (thermal) heat sources were fabricated by the Oak Ridge National Laboratory (ORNL) for the purpose of fueling a 500-watt (electric) thermoelectric generator as part of the US Department of Energy's Byproducts Utilization Program (BUP). Each of the sources, which are the largest ever assembled, consist of hot-pressed pellets of /sup 90/Sr fluoride, doubly encapsulated in three Haynes-25 inner capsules and in a Hastelloy-S outer capsule. The total /sup 90/Sr inventory of all three sources is 1.12 million curies. The sources were fabricated at the ORNL Fission Product Development Laboratory (FPDL), which is a facility that is capable of processing multi-megacurie quantities of radioactive materials, chiefly /sup 137/Cs and /sup 90/Sr. The source was tested to determine compliance with all of the IAEA Safety Series No. 33 requirements. The source fabrication, assembly, and testing are described in the presentation.
Date: August 1, 1986
Creator: DeVore, J.R.; Haff, K.W. & Tompkins, J.A.
Partner: UNT Libraries Government Documents Department

Energy dependence of complete and incomplete fusion for mass 56 entrance channel systems at E/sub lab/ > 10 MeVnucleon

Description: Three entrance channels /sup 16/O + /sup 40/Ca, /sup 28/Si + /sup 28/Si, and /sup 32/S + /sup 24/Mg forming the /sup 56/Ni compound nucleus have been studied in the energy range 5 to 17 MeVnucleon. Time-of-flight measurements provided mass identification and allowed for extraction of velocity distributions. These distributions were used to identify evaporation residues and to decompose the evaporation residues yeilds into complete and incomplete fusion components using evaporation code calculations. The velocity centroids as function of angle and mass are found to put constraints on the possible pre-equilibrium emission of light particles. 16 refs., 6 figs
Date: January 1, 1987
Creator: Kovar, D.G.; Beck, C.; Vineyard, M.F.; Janssens, R.V.F.; Sanders, S.J.; Stephans, G.S.F. et al.
Partner: UNT Libraries Government Documents Department

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

Description: 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 deep structures and broad zones of cerebral cortex which appeared normal on x-ray CT (XCT) and /sup 99m/Tc pertechnetate scans. In patients with partial epilepsy, who had unilateral or focal electrical abnormalities, interictal /sup 18/FDG scan patterns clearly showed localized regions of decreased (20 to 50%) LCMR/sub glc/, which correlated anatomically with the eventual EEG localization.
Date: January 1, 1980
Creator: Kuhl, D.E.; Phelps, M.E. & Engel, J. Jr.
Partner: UNT Libraries Government Documents Department

Input and decayed values of radioactive liquid wastes discharged to the ground in the 200 Areas through 1975

Description: Low and intermediate level liquid wastes from chemical separations processing of spent reactor fuel elements have been discharged to the ground in the 200-Areas since 1944. Large volumes of process cooling water, normally free of radioactive contaminants, are discharged to surface ditches or natural surface depressions (ponds). Lesser volumes of liquid waste such as steam condensates, process condensates, scavenged process waste supernatants, and plutonium processing wastes have been, or are being discharged to subsurface disposal sites (cribs). Only input volumes and radioactivity discharged to each disposal site have been reported periodically.
Date: July 8, 1976
Creator: Anderson, J.D.
Partner: UNT Libraries Government Documents Department

Los Alamos experiment on the beta decay of free molecular tritium

Description: The beta spectrum of the decay of free molecular tritium has been accurately measured in order to search for a finite anti nu/sub e/ mass. The betas originating from the decay of free tritium molecules in a differentially pumped source region were momentum analyzed in a toroidal beta spectrometer with 36-eV resolution. The final state effects in molecular tritium are accurately known and the data thus allow us to set an upper limit of 29.3 eV on the anti nu/sub e/ mass at the 95% confidence level.
Date: January 1, 1986
Creator: Robertson, R.G.H.; Bowles, T.J.; Browne, J.C.; Maley, M.P.; Wilkerson, J.F.; Knapp, D.A. et al.
Partner: UNT Libraries Government Documents Department

Advances in the helium-jet coupled on-line mass separator RAMA. [Recoil Atom Mass Analyzer]

Description: 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 showed a factor of five increase in yield over the old hollow-cathode, anode-extraction source. A differentially-pumped-tape drive system compatible with both ..gamma..-..gamma.. and ..beta..-..gamma.. experiments has been incorporated into the general detection system. All major operating parameters will soon be monitored by a complete stand-alone microprocessor system which will eventually be upgraded to a closed-loop control system.
Date: January 1, 1980
Creator: Moltz, D M; Aysto, J; Cable, M D; Parry, R F; Haustein, P E; Wouters, J M et al.
Partner: UNT Libraries Government Documents Department

Decay of mass-separated /sup 118/Ag to levels in /sup 118/Cd

Description: A study of the gamma-ray de-excitation following the beta decay of /sup 118/Ag using the TRISTAN on-line isotope separator is reported. Gamma-ray singles, gamma-gamma coincidence, and gamma-ray multiscale measurements were made using Ge(Li) detectors. A total of 52 gamma rays were observed in the decay of /sup 118/Ag. Thirty-eight of these were placed in a level scheme for /sup 118/Cd consisting of 20 excited states up to 3382 keV. Gamma-ray multiscale measurements indicated that /sup 118/Ag has an isomeric state at 128 keV with a half-life of 2.0 +- 0.2 seconds. The ground state half-life is 3.76 +- 0.15 seconds. The /sup 118/Ag decay scheme is compared with a previous decay study. The level scheme systematics are discussed and compared with recent collective model calculations.
Date: April 1, 1978
Creator: Margetan, D. R.
Partner: UNT Libraries Government Documents Department