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Interference control in low-level /sup 129/I analysis

Description: Neutron activation analysis for /sup 129/I at levels close to the detection limit requires consideration of radionuclide and nuclear reaction interferences. Low-level gamma-ray spectrometer methods for detection and measurement of interferences have been developed. Procedures which control or eliminate potential /sup 129/I measurement errors during pre-irradiation separation, neutron activation, post-irradiation separation, radiation counting and data analysis are needed.
Date: January 1, 1981
Creator: Brauer, F.P.; Strebin, R.S. Jr.; Fager, J.E. & Kaye, J.H.
Partner: UNT Libraries Government Documents Department

Design and qualification testing of a strontium-90 fluoride heat source

Description: The Strontium Heat Source Development Program began at the Pacific Northwest Laboratory (PNL) in 1972 and is scheduled to be completed by the end of FY-1981. The program is currently funded by the US Department of Energy (DOE) By-Product Utilization Program. The primary objective of the program has been to develop the data and technology required to permit the licensing of power systems for terrestrial applications that utilize /sup 90/SrF/sub 2/-fueled radioisotope heat sources. A secondary objective of the program has been to design and qualification-test a general purpose /sup 90/SrF/sub 2/-fueled heat source. The effort expended in the design and testing of the heat source is described. Detailed information is included on: heat source design, licensing requirements, and qualification test requirements; the qualification test procedures; and the fabrication and testing of capsules of various materials. The results obtained in the qualification tests show that the outer capsule design proposed for the /sup 90/SrF/sub 2/ heat source is capable of meeting current licensing requirements when Hastelloy S is used as the outer capsule material. The data also indicate that an outer capsule of Hastelloy C-4 would probably also meet licensing requirements, although Hastelloy S is the preferred material. Therefore, based on the results of this study, the general purpose /sup 90/SrF/sub 2/ heat source will consist of a standard WESF Hastelloy C-276 inner capsule filled with /sup 90/SrF/sub 2/ and a Hastelloy S outer capsule having a 2.375-in. inner diameter and 0.500-in. wall thickness. The end closures for this study, the general purpose /sup 90/SrF/sub 2/ heat a Hastelloy S outer capsule having a 2.375-in. inner diameter and 0.500-in. wall thickness. The end closures for the outer capsule will utilize an interlocking joint design requiring a 0.1-in. penetration closure weld. (LCL)
Date: December 1, 1981
Creator: Fullam, H.T.
Partner: UNT Libraries Government Documents Department

Nuclear waste management. Quarterly progress report, April-June 1981

Description: Reports and summaries are presented for the following: high-level waste process development; alternative waste forms; TMI zeolite vitrification demonstration program; nuclear waste materials characterization center; TRU waste immobilization; TRU waste decontamination; krypton implantation; thermal outgassing; iodine-129 fixation; NWVP off-gas analysis; monitoring and physical characterization of unsaturated zone transport; well-logging instrumentation development; verification instrument development; mobility of organic complexes of radionuclides in soils; handbook of methods to decrease the generation of low-level waste; waste management system studies; waste management safety studies; assessment of effectiveness of geologic isolation systems; waste/rock interactions technology program; high-level waste form preparation; development of backfill materials; development of structural engineered barriers; disposal charge analysis; and analysis of spent fuel policy implementation.
Date: September 1, 1981
Creator: Chikalla, T.D. & Powell, J.A.
Partner: UNT Libraries Government Documents Department

Nuclear waste management. Quarterly progress report, October through December 1980

Description: Progress reports and summaries are presented under the following headings: high-level waste process development; alternative waste forms; nuclear waste materials characterization center; TRU waste immobilization; TRU waste decontamination; krypton solidification; thermal outgassing; iodine-129 fixation; monitoring and physical characterization of unsaturated zone transport; well-logging instrumentation development; mobility of organic complexes of radionuclides in soils; waste management system studies; waste management safety studies; assessment of effectiveness of geologic isolation systems; waste/rock interactions technology; high level waste form preparation; development of backfill material; development of structural engineered barriers; ONWI disposal charge analysis; spent fuel and fuel component integrity program; analysis of spent fuel policy implementation; analysis of postulated criticality events in a storage array of spent LWR fuel; asphalt emulsion sealing of uranium tailings; liner evaluation for uranium mill tailings; multilayer barriers for sealing of uranium tailings; application of long-term chemical biobarriers for uranium tailings; revegetation of inactive uranium tailing sites; verification instrument development.
Date: March 1, 1981
Creator: Chikalla, T.D. & Powell, J.A. (comps.)
Partner: UNT Libraries Government Documents Department

Nuclear-waste-management. Quarterly progress report, July-September 1981

Description: Progress reports and summaries are presented for the following: high-level waste process development, alternate waste forms; TMI zeolite vitrification demonstration program; nuclear waste materials characterization center; TRU waste immobilization; TRU waste decontamination; krypton implantation; thermal outgassing; iodine-129 fixation; NWVP off-gas analysis; monitoring and physical characterization of unsaturated zone transport; well-logging instrumentation development; verification instrument development; mobility of organic complexes of radionuclides in soils; handbook of methods to decrease the generation of low-level waste; waste management system studies; waste management safety studies; assessment of effectiveness of geologic isolation systems; waste/rock interactions technology program; high-level waste form preparation; development of backfill materials; development of structural engineered barriers; disposal charge analysis; analysis of spent fuel policy implementation; spent fuel and fuel pool component integrity program; analysis of postulated criticality events in a storage array of spent LWR fuel; asphalt emulsion sealing of uranium mill tailings; liner evaluation for uranium mill tailings; multilayer barriers for sealing uranium tailings; application of long-term chemical biobarriers for uranium tailings; and revegetation of inactive uranium tailings sites.
Date: December 1, 1981
Creator: Chikalla, T.D. & Powell, J.A. (comps.)
Partner: UNT Libraries Government Documents Department

Selection of a form for fixation of iodine-129

Description: This report summarizes work on the selection of an /sup 129/I disposal form. Iodine compounds have been screened on the basis of solubilities, thermal stabilities, cost and availability, toxicity of the cation, and the thermodynamic resistance to oxidation and hydrolysis, and leaching of that compound in portland type III cement. Also considered were iodine capture technology, disposal criteria or guidelines, and the disposal site/strategy. The recommended iodine fixation forms, based on their leach resistance and chemical stability and contingent on the disposal strategy/site and capture technique, are silver iodide in cement and barium, calcium, or strontium, and mercuric iodates in cement. Iodine sodalite appears promising and merits further study. If compatible with disposal requirements, the recommended forms for Mercurex and Iodox are insoluble iodates in cement and for silver sorbents the sorbents in cement or AgI in cement. Conversion between the different oxidation states of iodine is feasible but complicates the iodine treatment. For the different disposal strategies, isotopic dilution or ocean disposal has the least stringent disposal form requirements. Any of the recommended forms should be suitable with proper site selection. Isolation in a geologic repository for thousands of years requires the disposal form to be thermally and chemically stable and resistant to leaching at elevated temperatures. Probably the best form studied for isolation is silver iodide in cement. For extraterrestrial disposal, the disposal form may have to withstand reentry impact and surface disposal in the event of an aborted mission; this assumes the capsule is not recovered. Thus the primary containment barrier is critical. The suggested iodine form for space disposal is a heavy metal iodide.
Date: December 1, 1981
Creator: Burger, L.L.; Scheele, R.D. & Wiemers, K.D.
Partner: UNT Libraries Government Documents Department

Use of nuclear resonant scattering of gamma rays for in vivo measurement of iron

Description: A technique for determination of elements in human body in-vivo, utilizing nuclear resonant scattering of gamma rays has been developed. 847 keV photons emitted from a gaseous /sup 56/MnCl/sub 2/ source are resonantly scattered from /sup 56/Fe present in the body. The detection of these gamma rays is used to estimate the iron content of the liver or heart of patients. Details of the calibration procedure and potential molecular effects are described.
Date: January 1, 1981
Creator: Vartsky, D.; Wielopolski, L.; Ellis, K.J. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Krypton-85 hydrofracture engineering feasibility and safety evaluation

Description: Engineering studies have been made to determine the hazards associated with the disposal of /sup 85/Kr using the hydrofracture process. To assess the hazards, an effort has been made to identify the equipment required to entrain and dissolve the noble gas into the grout stream at hydrofracture pressure (up to 350 bar). Off-the-shelf or slightly modified equipment has been identified for safe and effective compression and gas-grout mixing. Each monthly injection disposes of 1.6 x 10/sup 6/ Ci of /sup 85/Kr. By connecting only one gas cylinder to the injection system at a time, the maximum amount of krypton likely to be released as a result of equipment failure is limited to 128,000 Ci. An evaluation by Los Alamos Technical Associates shows that releasing this amount of gas in less than one hour under worst-case meteorological conditions through a 30-m stack would result in a whole-body dose of 170 millirem at a distance of 1 km from the facility. A krypton collection and recovery system can further reduce this dose to 17 millirem; increasing the distance to the site boundary to 3 km can also reduce the dose by a factor of ten. Lung and skin dose estimates are 1.6 and 120 times the whole-body dose, respectively. These are all worst-case values; releases under more typical conditions would result in a significantly lower dose. No insurmountable safety or engineering problems have been identified.
Date: July 1, 1981
Creator: Peretz, F.J.; Muller, M.E. & Pan, P.Y.
Partner: UNT Libraries Government Documents Department

Parameterization of the bremsstrahlung spectrum

Description: A parameterization is provided for the bremsstrahlung spectrum in the incident electron energy range 10 to 500 keV for all elements, with particular emphasis on the range 20 to 100 keV for Z = 41 to 92. A general accuracy of 20% is achieved, with 50% in the worst cases, in most ranges utilizing simple one variable functions.
Date: August 31, 1981
Creator: Feng, I.J. & Pratt, R.H.
Partner: UNT Libraries Government Documents Department

Coordination chemistry of several radius-sensitive complexones and applications to lanthanide-actinide separations

Description: The relationships between the lanthanide complex formation equilibria and the lanthanide-actinide separation application of three radius sensitive ligands have been studied. The consecutive stepwise formation constants of the 1:1, 2:1, and 3:1 chelate species formed by the interaction of DHDMB and the tripositive lanthanides and yttrium were determined potentiometrically at 0.1 M ionic strength and 25/sup 0/C. Results indicate that three different coordination modes, one tridentate and two bidentate are in evidence. Tracer level /sup 241/Am - /sup 155/Eu cation-exchange experiments utilizing DHDMB eluents indicate that this dihydroxycarboxylate does not form a sufficiently strong americium complex to elute that actinide ahead of europium. The overall stability of the americium 3:1 complex appears intermediate between samarium and europium. Cation-exchange elutions of /sup 241/Am, /sup 155/Eu, and /sup 160/Tb mixtures with EEDTA solutions prove that the EEDTA ligand is capable of eluting americium ahead of all of the tripositive lanthanide cations. The minimum separation occurs with terbium, where the Am-Tb separation factor is 1.71. 1,5-diaminopentane-N,N,N',N'-tetraacetic acid (PMDTA) was synthesized using cation exchange. A mathematical method was developed for the formation constants of the protonated and unprotonated lanthanide-PMDTA complexes from potentiometry. Cation-exchange elutions of tracer quantities of Am, Eu, and Tb revealed that terbium is eluted ahead of both americium and europium.
Date: October 1, 1981
Creator: Potter, M.W.
Partner: UNT Libraries Government Documents Department

Search for magnetism in hcp epsilon-Fe

Description: The results of recent experimental investigation which extends the search for magnetic ordering in the high-pressure, hcp phase of iron (epsilon-phase) to a temperature of 0.030 K are reported. Moessbauer effect measurements were performed in the pressure range from atmospheric pressure to 21.5 GPa on a foil of natural iron (doped with /sup 57/Co). Measurements were made of the properties of both the ..cap alpha..- and epsilon-phase constituents of the sample. No measurable magnetic hyperfine field was observed in the epsilon-phase from any of the spectra at pressures as high as 21.5 GPa and temperatures as low as 0.030 K.
Date: January 1, 1981
Creator: Cort, G.; Taylor, R.D. & Willis, J.O.
Partner: UNT Libraries Government Documents Department

Environmental monitoring report, 1980: Pinellas Plant

Description: Results of the monitoring program at the Pinellas Plant are described. Small quantities of tritium gas, tritium oxide, carbon-14 labeled solvent and krypton-85 gas were released from the plant during the year. Average maximum ground level concentrations of these radioisotopes were all significantly less than 0.1% of the recommended guide for continuous nonoccupational exposure. Off-site releases of liquid effluents were analyzed for compliance with the National Pollutant Discharge Elimination System (NPDES). Analyses were performed for biochemical oxygen demand, suspended solids, fecal coliform bacteria, pH, nitrogen, phosphorus, arsenic, chlorides, chromium, copper, cyanides, detergents, fluorides, iron, lead, mercury, oil plus greases, phenols, turbidity, and zinc. In addition to the non-radioactive parameters listed above, a small quantity of radioactive tritium oxide was released in the effluent. Analyses showed the average concentration was 0.20% of the nonoccupational exposure guide. Site perimeter and off-site air samples for tritium gas and tritium oxide, as well as off-site surface water samples obtained to distance of 9.6 kilometers (6 miles) from the plant site and analyzed for tritium content, showed levels significantly less than 0.1% of the recommended guide for continuous nonoccupational exposure. Small sealed plutonium sources containing approximately 80% plutonium-238 oxide and 20% plutonium-239 oxide and other isotopes, are utilized at this site. No plutonium was released to the environment.Calculations were made to determine the radiation doses resulting from releases of tritium oxide, /sup 85/Kr, and /sup 14/C to: an individual at the site boundary; individuals in the closest residential area; and the population within 80 kilometers (50 miles) of the plant site. The total dose commitment to the population residing within 80 kilometers was determined to be 0.55 man-rem as compared to the annual dose from natural radiation of 223,165 man-rem.
Date: March 1, 1981
Partner: UNT Libraries Government Documents Department

Biomedical research with cyclotron produced radionuclides. Progress report, February 1, 1981-December 31, 1981

Description: Progress is reported in the following areas: evaluation of chemotherapeutic regimens in solid tumors using /sup 13/N-labelled amino acids; organ imaging with /sup 13/N-labelled L-amino acids; imaging with /sup 111/In-labelled-autologous platelets; synthesis and biological studies of /sup 111/In-labelled ammonia and L-amino acids; synthesis and evaluation for pancreatic imaging of /sup 11/C-labelled amino acides; radioisotope monitoring of myocardiol function; synthesis of /sup 11/C-labelled precursor compounds; reduction of radiation exposure through automation and remote control; development of an anhydrous /sup 18/F target; evaluation of radiolabelled 5-fluorouracils for scintigraphy; and methods of data analysis, modeling, and unproving instrumentation for positron-emission tomography. (EDB)
Date: September 1, 1981
Creator: Laughlin, J.S.
Partner: UNT Libraries Government Documents Department

Comparison of experimentally determined spent-fuel compositions with ORIGEN 2 calculations

Description: The specific experimental measurements of interest here involve the determination of parameters related to the actinide and fission product composition of samples from five elements taken from fuel assemblies discharged from the Turkey Point Unit 3 PWR. Two fuel assemblies were obtained for the purposes of nondestructive and destructive assay. These assemblies were initially fueled with 448 kg of UO/sub 2/ enriched to 2.556 wt % /sup 235/U and then irradiated for 851 full-power days. Five elements were then removed, and assay samples were taken from each element near the core midplane. The relevant parameters measured were /sup 148/Nd//sup 238/U, /sup 239/Pu//sup 238/U, and the isotopic compositions of U, Pu, Kr, and Xe. Fuel depletion calculations were performed using the updated ORIGEN2 PWR model. The burnup of the fuel was determined by adjusting the ORIGEN2 fuel burnup to match the experimentally determined /sup 148/Nd//sup 238/U ratio for each fuel element. The resulting burnup was then used to calculate the other experimentally determined parameters listed above. The agreement between ORIGEN2 and the experimental results is very good, with the average error for five samples being < 4% for most parameters. Based on this comparison, it appears that the ORIGEN2 computer code is capable of accurately calculating the composition of irradiated fuel from a modern PWR. However, well-characterized experimental measurements should continue to be obtained for validation purposes because the calculated values of many nuclides, particularly the minor actinides, still have significant uncertainties.
Date: January 1, 1981
Creator: Croff, A.G.
Partner: UNT Libraries Government Documents Department

In situ determination of /sup 241/Am on Enewetak Atoll. Date of survey: July 1977-December 1979

Description: An in situ gamma ray spectrometer system was operated at Enewetak Atoll from July 1977 to December 1979 in support of the Enewetak Cleanup Project. The system employed a high purity germanium planar detector suspended at a height of 7.4 m above ground. Conversion factors were established to relate measured photopeak count rate data to source concentration in the soil. Data obtained for /sup 241/Am, together with plutonium-to-americium ratios obtained from soil sample analyses, were used to establish area-averaged surface (0 to 3 cm) transuranic concentration values. In areas which exceeded cleanup criteria, measurements were made in an iterative fashion to guide soil removal until levels were reduced below the cleanup criteria. Final measurements made after soil removal had been completed were used to document remaining surface transuranic concentration values and to establish external exposure rate levels due to /sup 137/Cs and /sup 60/Co.
Date: November 1, 1981
Creator: Tipton, W.J.; Fritzsche, A.E.; Jaffe, R.J. & Villaire, A.E.
Partner: UNT Libraries Government Documents Department

Development of more efficacious Tc-99m organ imaging agents for use in nuclear medicine by analytical characterization of radiopharmaceutical mixtures. Progress report, May 1, 1981-April 30, 1982

Description: The objectives of this year's research were to develop a method for rapidly determining TcO/sub 4//sup -/ in /sup 99/Mo//sup 99m/Tc generator eluates, to improve the ability to chromatographically determine individual Tc-HEDP complexes in radiopharmaceuticals, and to investigate the effects of TcO/sub 4//sup -/ concentration and electrochemical reduction on the types and relative amounts of Tc-HEDP complexes present in a radiopharmaceutical formulation. A rapid and sensitive high performance liquid chromatographic (HPLC) method for the quantitative determination of pertechnetate (TcO/sub 4//sup -/) was developed. This HPLC-based analysis may be of considerable utility in assessing the history and function of /sup 99/MO/sup 99m/Tc generators as well as in the routine analysis of reduced technetium radiopharmaceuticals for the presence of undesired TcO/sub 4//sup -/. Encouraging results were obtained on a dimethyl amine column using aqueous (NH/sub 4/)/sub 2/SO/sub 4/ as the mobile phase. The preparation of Tc(NaBH/sub 4/) HEDP radiopharmaceutical analogues using varying concentrations of total TcO/sub 4//sup -/ shows a dramatic effect in the number and distribution of Tc-HEDP complexes over a TcO/sub 4//sup -/ concentration range of 10/sup -2/ to 10/sup -8/M. These results suggest that total TcO/sub 4//sup -/ concentration is an important parameter to be considered in the preparation of a specific Tc-HEDP complex to improve skeletal imaging. The preparation of Tc(electrode) HEDP radiopharmaceutical analogues by using electrochemical reduction was explored. The resulting solutions contain Tc-HEDP complexes that are tentatively identified as being the same complexes formed by NaBH/sub 4/ reduction, although the relative concentrations of these complexes are quite different with the two modes of reduction. Thus, electrochemical reduction shows promise as a viable route to the preparation of specific Tc-HEDP complexes for improved skeletal imaging.
Date: December 1, 1981
Creator: Heineman, W.R. & Deutsch, E.A.
Partner: UNT Libraries Government Documents Department

Validation of annual average air concentration predictions from the AIRDOS-EPA computer code

Description: The AIRDOS-EPA computer code is used to assess the annual doses to the general public resulting from releases of radionuclides to the atmosphere by Oak Ridge National Laboratory (ORNL) facilities. This code uses a modified Gaussian plume equation to estimate air concentrations resulting from the release of a maximum of 36 radionuclides. Radionuclide concentrations in food products are estimated from the output of the atmospheric transport model using the terrestrial transport model described in US Nuclear Regulatory Commission Regulatory Guide 1.109. Doses to man at each distance and direction specified are estimated for up to eleven organs and five exposure modes. To properly use any environmental transport model, some estimate of the model's predictive accuracy must be obtained. Because of a lack of sufficient data for the ORNL site, one year of weekly average /sup 85/Kr concentrations observed at 13 stations located 30 to 150 km distant from an assumed-continuous point source at the Savannah River Plant, Aiken, South Carolina, have been used in a validation study of the atmospheric transport portion of AIRDOS-EPA. The predicted annual average concentration at each station exceeded the observed value in every case. The overprediction factor ranged from 1.4 to 3.4 with an average value of 2.4. Pearson's correlation between pairs of logarithms of observed and predicted values was r = 0.93. Based on a one-tailed students's test, we can be 98% confident that for this site under similar meteorological, release, and monitoring conditions no annual average air concentrations will be observed at the sampling stations in excess of those predicted by the code. As the averaging time of the prdiction decreases, however, the uncertainty in the prediction increases.
Date: January 1, 1981
Creator: Miller, C.W.; Fields, D.E. & Cotter, S.J.
Partner: UNT Libraries Government Documents Department

Iodine-129 separation and determination by neutron activation analysis

Description: A method is described for analysis of /sup 129/I in fission product mixtures originating from fuel reprocessing studies and low-level wastes. The method utilizes conventional iodine valence adjustment and solvent extraction techniques to chemically separate /sup 129/I from most fission products. The /sup 129/I is determined by neutron irradiation and measurement of the 12.4 h /sup 130/I produced by the neutron capture reaction. Special techniques were devised for neutron irradiation of /sup 129/I samples in the pneumatic tube irradiation facilities at the High Flux Isotope (HFIR) and Oak Ridge Research (ORR) Reactors. Chemically separated /sup 129/I is adsorbed on an anion exchange resin column made from an irradiation container. The loaded resin is then irradiated in either of the pneumatic facilities to produce /sup 130/I. Sensitivity of the analysis with the HFIR facility (flux: 5 x 10/sup 14/ n/cm/sup 2//sec) and a 100-second irradiation time is approximately 0.03 nanograms. Samples up to 250 ml in volume can be easily processed.
Date: January 1, 1981
Creator: Bate, L.C. & Stokely, J.R.
Partner: UNT Libraries Government Documents Department

Laboratory studies of radionuclide distributions between selected groundwaters and geologic media. Progress report, October 1, 1979-September 30, 1980

Description: During FY-1980, Los Alamos Scientific Laboratory contributions to the Waste/Rock Interactions Technology program were primarily in the areas of migration-rate studies using crushed rock, whole core, and fractured core columns; parametric studies of variables which may influence radionuclide sorption-desorption behavior; and initial studies of actinide chemistry in near-neutral solutions and Eh control. Batch experiments in both air and a controlled atmosphere (nitrogen, less than or equal to 0.2 ppM oxygen, less than or equal to 20 ppM carbon dioxide) for the sorption of several radionuclides on granite and argillite were completed. These data also provided informaton on the effects of other parameters, such as particle size and contact time. All nine elements studied had different sorption ratios for argillite when measured under the controlled atmosphere than when measured in air, except possibly for americium where any effect was smaller than the standard deviations. As expected, strontium, cesium, and barium are least affected by the presence or absence of oxygen and carbon dioxide. Columns of crushed rock and solid and cracked cores were used to study the migration of radionuclides through such materials. In general, sorption ratios measured by batch techniques are 2 to 3 times greater than those for columns; however, a wide variation in behavior was observed, depending upon the element and the mineralogy. Work has begun on a system wherein traced groundwater is circulated through a crushed rock column; this should provide a link between the usual, single-pass, crushed rock columns and the batch experiments. Materials characterization has continued, and techniques for the determination of Fe(II) in silicate rocks and groundwater have been made operational. Work on the fundamental solution chemistry of the actinides has been started.
Date: January 1, 1981
Creator: Daniels, W.R. (comp.)
Partner: UNT Libraries Government Documents Department

Nuclear medicine technology progress report for quarter ending June 30, 1980

Description: Results of experiments demonstrated that the alkyl portion of 9-telluraheptadecanoic acid (9-THDA) is retained in the myocardial tissue of rats to the same extent as radioactivity from /sup 123m/Te-9-THDA. Tissue distribution experiments in rats one hr after injection of 10-(/sup 14/C)-9-telluraheptadecanoic acid were compared with the results of a parallel study using /sup 123m/Te-9-THDA. The results indicate that the alkyl region of 9-THDA is retained in the myocardium and that labeling of this portion of the 9-THDA molecule with radiohalogens such as /sup 123/I may be an attractive approach for evaluation of myocardial function. Results of preliminary studies for the development of radiolabeled barbiturates as a new class of agents for the measurement of regional blood perfusion in the brain are also described. Several new barbiturates substituted at the C-5 position were prepared and characterized. These compounds will be labeled with /sup 117m/Sn, /sup 75/Se, and /sup 123m/Te and brain uptake studies performed in rats. Studies of arsenic trioxide (As/sub 2/O/sub 3/) toxicity for human cells in the diffusion chamber assay system have continued. Studies employing /sup 74/As/sub 2/O/sub 3/ have demonstrated that uptake of radioactivity from test substances administered to rats can be detected in cells taken from the intraperitoneally-implanted diffusion chambers. Preliminary synthetic studies of gold-based antirheumatoid complexes are also reported. Several /sup 11/C-labeled amino acids have been prepared for clinical testing. Platinum-195m-labeled-cis-dichlorodiammine-platinum(II) was supplied to collaborators for further testing and /sup 75/Se- and /sup 123m/Te-labeled long-chain fatty acids were supplied to several medical investigators for the evaluation of myocardial function in experimental animals. (ERB)
Date: January 1, 1981
Creator: Knapp, Jr., F. F.
Partner: UNT Libraries Government Documents Department

Radionuclide reactions with groundwater and basalts from Columbia River basalt formations

Description: Chemical reactions of radionuclides with geologic materials found in Columbia River basalt formations were studied. The objective was to determine the ability of these formations to retard radionuclide migration from a radioactive waste repository located in deep basalt. Reactions that can influence migration are precipitation, ion-exchange, complexation, and oxidation-reduction. These reactions were studied by measuring the effects of groundwater composition and redox potential (Eh) on radionuclide sorption on fresh basalt surfaces, a naturally altered basalt, and a sample of secondary minerals associated with a Columbia River basalt flow. In addition, radionuclide sorption isotherms were measured for these materials and reaction kinetics were determined. The radionuclides studied were /sup 137/Cs, /sup 85/Sr, /sup 75/Se, /sup 95m/Tc, /sup 237/Np, /sup 241/Am, /sup 226/Ra and /sup 237/Pu. The Freundlich equation accurately describes the isotherms when precipitation of radionuclides does not occur. In general, sorption increased in the order: basalt < altered basalt < secondary minerals. This increase in sorption corresponds to increasing surface area and cation exchange capacity. The Eh of the system had a large effect on technetium, plutonium, and neptunium sorption. Technetium(VII), Pu(VI), and Np(V) are reduced to Tc(IV), Pu(IV), and Np(IV), respectively, under Eh conditions expected in deep basalt formations. The kinetics of radionuclide sorption and basalt-groundwater reactions were observed over a period of 18 weeks. Most sorption reactions stabilized after about four weeks. Groundwater composition changed the least in contact with altered basalt. Contact with secondary minerals greatly increased Ca, K, and Mg concentrations in the groundwater.
Date: June 1, 1981
Creator: Barney, G.S.
Partner: UNT Libraries Government Documents Department

Studies of yrast and continuum states in A=140-160 nuclei. Progress report, January 1, 1980-December 31, 1980. [Purdue Univ. , 1/1/80-12/31/80]

Description: The structure of nuclei in the A approx. 150 region was investigated by in-beam ..gamma..-ray spectroscopy using heavy-ion beams, mostly from the Argonne Tandem-Linac. Results for the nuclei /sup 148/Dy, /sup 149/Dy, /sup 153/Dy, /sup 154/Dy, /sup 149/Ho, and /sup 150/Ho are summarized. The feeding of yrast states in these nuclei and the link between the highest known yrast states and the continuum region were also studied. 6 figures.
Date: January 1, 1981
Creator: Daly, P.J.
Partner: UNT Libraries Government Documents Department

In vivo detection, localization, and measurement of radionuclides in man: a detection system for the localization and measurement of small amounts of photon emitters. Progress report, September 1, 1979-December 1, 1980

Description: The objectives of this research involve the design, development, and testing of a new type of photon detection system which can provide, simultaneously, magnitude and positional data regarding a radioactive source, without utilizing a high-Z collimator. This system employs the principle of active collimation, i.e., the geometric configuration of crystal elements results in certain members being shielded from oblique-angle rays, thereby providing spatial resolution characteristics. Inasmuch as events occurring in the promontory shielding crystals can be used to determine activity levels of the emitter, a greater counting efficiency is attainable than that with other currently available systems. Owing to optical and scintillation characteristics, and amplifier parameters, along with masking of the common PM tube, each of the five scintillation crystals in the detector configuration produces a separate, delineable spectral peak.
Date: January 15, 1981
Creator: Laurer, G.R.
Partner: UNT Libraries Government Documents Department

Northern Marshall Islands radiological survey: sampling and analysis summary

Description: A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for /sup 241/Am, 6569 for /sup 137/Cs, 4535 for /sup 239 +240/Pu, 4431 for /sup 90/Sr, 1146 for /sup 238/Pu, 269 for /sup 241/Pu, and 114 each for /sup 239/Pu and /sup 240/Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included.
Date: July 23, 1981
Creator: Robison, W.L.; Conrado, C.L.; Eagle, R.J. & Stuart, M.L.
Partner: UNT Libraries Government Documents Department