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Development and use of a fifteen year-old equivalent mathematical phantom for internal dose calculations. [Radiation dose distributions from /sup 99m/Tc-labeled compounds]

Description: The existence of a phantom based on anatomical data for the average fifteen-year-old provides for a proficient means of obtaining estimates of absorbed dose for children of that age. Dimensions representative of an average fifteen-year-old human, obtained from various biological and medical research, were transformed into a mathematical construct of idealized shapes of the exterior, skeletal system, and internal organs of a human. The idealization for an average adult presently in use by the International Commission on Radiological Protection was used as a basis for design. The mathematical equations describing the phantom were developed to be readily adaptable to present-day methods of dose estimation. Typical exposure situations in nuclear medicine have previously been modeled for existing phantoms. With no further development of the exposure model necessary, adaptation to the fifteen-year-old phantom demonstrated the utility of the design. Estimates of absorbed dose were obtained for the administration of two radiopharmaceuticals, /sup 99m/Tc-sulfur colloid and /sup 99m/Tc-DMSA. (auth)
Date: June 1, 1976
Creator: Jones, R. M.; Poston, J. W.; Hwang, J. L.; Jones, T. D. & Warner, G. G.
Partner: UNT Libraries Government Documents Department

Solubility of krypton in liquid CO/sub 2/

Description: The solubility of krypton in liquid CO/sub 2/ was measured experimentally over essentially the entire liquid range of CO/sub 2/, from -53 to 29/sup 0/C. A tracer technique using /sup 85/Kr was employed, and equilibrated gas-liquid samples were analyzed in situ with a collimated counter. Dilute concentrations of krypton were used, and the data are expressed as a distribution ratio, Y/sub Kr//X/sub Kr/, the log of which is nearly linear with respect to temperature from the lowest temperature to about 20/sup 0/C, above which the values fall off rapidly toward a value of unity at the critical temperature. The numerical values obtained for the distribution ratio increase from 1.44 at 29/sup 0/C to 29.4 at -53/sup 0/C.
Date: June 1, 1976
Creator: Notz, K. J. & Meservey, A. B.
Partner: UNT Libraries Government Documents Department

Development of krypton-85 sources for the Bureau of Mines coal dust combustion analyzer. Operations Division final report. [Gaseous /sup 85/Kr encapsulated in Ta; x-ray source]

Description: Americium-241 used as a radiation source in a field instrument for measuring coal concentrations in mine dust presents a contamination hazard if the instrument is damaged. Alternative source designs based on /sup 85/Kr were developed and evaluated. Krypton-85 beta particles were used to excite x-rays from a target and the x-rays were used in place of the /sup 241/Am gamma radiation. Output of sources using /sup 85/Kr foils was not high enough because the concentration of /sup 85/Kr in the foils was too low. Output of sources using gaseous /sup 85/Kr, encapsulated in tantalum was adequate for the coal dust analyzer although the associated radiation field from /sup 85/Kr gamma rays make these sources inappropriate for application in a portable instrument.
Date: June 1, 1976
Creator: Bradley, N. C.; Case, F. N.; Cutshall, N. H. & Haff, K. W.
Partner: UNT Libraries Government Documents Department

Decay of /sup 99/Mo

Description: Relative intensities for K x-rays and gamma rays emanating from /sup 99/Mo in equilibrium with its /sup 99/Tc* daughter have been measured using several Ge photon detectors. Combining these intensities with an evaluated set of electron-conversion coefficients has provided a set of absolute intensities for the observed gamma rays. The absolute intensity for the dominant 140.5-keV gamma ray in /sup 99/Tc was determined to be 90.7 +- 0.6/100 /sup 99/Mo disintegrations for /sup 99/Mo decay in equilibrium with decay of the /sup 99/Tc* daughter.
Date: December 14, 1976
Creator: Dickens, J. K. & Love, T. A.
Partner: UNT Libraries Government Documents Department

Proceedings of a symposium on the occasion of the 40th anniversary of the nuclear shell model

Description: This report contains papers on the following topics: excitation of 1p-1h stretched states with the (p,n) reaction as a test of shell-model calculations; on Z=64 shell closure and some high spin states of {sup 149}Gd and {sup 159}Ho; saturating interactions in {sup 4}He with density dependence; are short-range correlations visible in very large-basis shell-model calculations ; recent and future applications of the shell model in the continuum; shell model truncation schemes for rotational nuclei; the particle-hole interaction and high-spin states near A-16; magnetic moment of doubly closed shell +1 nucleon nucleus {sup 41}Sc(I{sup {pi}}=7/2{sup {minus}}); the new magic nucleus {sup 96}Zr; comparing several boson mappings with the shell model; high spin band structures in {sup 165}Lu; optical potential with two-nucleon correlations; generalized valley approximation applied to a schematic model of the monopole excitation; pair approximation in the nuclear shell model; and many-particle, many-hole deformed states.
Date: March 1, 1990
Creator: Lee, T. S. H. & Wiringa, R. B. (eds.)
Partner: UNT Libraries Government Documents Department

Activation of cobalt by neutrons from the Hiroshima bomb

Description: A study has been completed of cobalt activation in samples from two new locations in Hiroshima. The samples consisted of a piece of steel from a bridge located at a distance of about 1300 m from the hypocenter and pieces of both steel and concrete from a building located at approximately 700 m. The concrete was analyzed to obtain information needed to calculate the cobalt activation in the two steel samples. Close agreement was found between calculated and measured values for cobalt activation of the steel sample from the building at 700 m. It was found, however, that the measured values for the bridge sample at 1300 m were approximately twice the calculated values. Thus, the new results confirm the existence of a systematic error in the transport calculations for neutrons from the Hiroshima bomb. 52 refs., 32 figs., 16 tabs.
Date: February 1, 1990
Creator: Kerr, G. D.; Dyer, F. F.; Emery, J. F.; Pace, J. V., III; Brodzinski, R. L. & Marcum, J.
Partner: UNT Libraries Government Documents Department

Summary of thyroid findings in Marshallese 22 years after exposure to radioactive fallout

Description: Inhabitants of several atolls in the Marshall Islands were accidently exposed to fallout radiation following a detonation of a high yield thermonuclear device during experiments at Bikini in the Pacific Proving Grounds in March 1954. The most serious acute effects of the exposure were due to penetrating gamma radiation. Contamination of the skin in the Rongelap group resulted in widespread beta burns and epilation. These lesions healed and hair regrew normally within several months. Radiochemical urine analyses revealed that measurable amounts of radionuclides, including /sup 131/I, were absorbed internally from ingestion of contaminated food and water and from inhalation. No acute effects due to this internal exposure were seen. Late thyroid effects from radioiodine absorption are described. Follow-up examinations have revealed, except for one fatal case of leukemia and extensive thyroid lesions, only a few findings that might be related to radiation exposure. A group of more than 200 Rongelap people who were relatives of exposed people, but had been away from the island at the time of the accident, moved back with the exposed people to their home island in 1957 and have served as an ideal comparison population for the studies. Results of medical examinations carried out on these populations for the past 22 years are reviewed.
Date: January 1, 1976
Creator: Conard, R A
Partner: UNT Libraries Government Documents Department

sup 31 P NMR analysis of coal moieties bearing -OH, -NH and -SH functions

Description: Research continues on the structural analysis of coal. In attempting to derivatize solid coal for solid state NMR analysis, we observed {sup 31}P NMR shifts in an unexpected region; these interesting leads will be pursued on the chance that the reaction we have evoked holds potential for yielding new coal characterizational information. Two very gratifying results have emerged from our {sup 119}Sn chemical shift measurements of a limited set of model compounds in pyridine. Firstly, the chemical shift dispersion is very large for phenols, alcohols and amides. Secondly, unlike {sup 119}Sn chemical shifts in hexane or chloroform, the shifts in pyridine are concentration independent.
Date: January 1, 1990
Creator: Verkade, J. G.
Partner: UNT Libraries Government Documents Department

Factors affecting mutational specificity induced by ionizing radiation and oxidizing radicals

Description: We propose to analyze the factors affecting the specificity of mutational change as induced by ionizing radiation and oxidizing radicals. We want to understand not only the rules the affect base substitution but also the mechanisms(s) by which additions and deletions are produced, since deletions are a common consequence of radiation. We wish to carry out this analysis in an in vitro mutation system that permits us to analyze the role of base sequence, of polymerase and of mutagenic agent. Our system is designed to screen out most direct breaks as a cause of mutation and should indicate the changes resulting from base damage to the DNA. Questions addressed include: 1. What types of base substitution mutations are induced by ionizing radiation and oxidizing radicals 2. Are deletions and/or additions produced 3. Is there a difference in type of mutation produced dependent on the polymerase used Do mammalian polymerase plus their accessory factors result in different patterns of mutation. 4. What is the mechanism by which base damage is converted to mutation. Our proposal was based on utilization of an in vitro system in which mutations generated by the in vitro copying of a reporter gene sequence could be readily scored.
Date: January 1, 1992
Creator: Strauss, B.
Partner: UNT Libraries Government Documents Department

Direct mass and lifetime measurements of neutron-rich nuclei up to A[approximately]100 using the TOFI spectrometer at LAMPF

Description: This project was directed toward the study of neutron-rich nuclei using the experimental facilities at LAMPF, which is a part of LANL. The principal results of the investigation include the discovery of many new isotopes along with a measurement of their masses and in particular those nuclides in the Z = 7--19 and 14 --26 regions of the chart of the nuclides.Thirty-four new nuclides were detected and studied with their masses being measured with relatively high accuracy, and an additional twenty-six that were previously known and measured were remeasured to an improved accuracy. Besides providing new information about the mass surface in new and extended redons of the chart of the nuclides, this investigation enabled properties and previously unknown structure of some of the nuclei to be determined such as nuclear deformation among some of the nuclides. Also a study of the neutron pairing gaps and the proton pairing gaps among these nuclides was made. Other developments also achieved included instrument (TOFI) improvements and upgrades and theoretical investigations into the masses of the hadrons.
Date: June 17, 1993
Creator: Lind, V. G.
Partner: UNT Libraries Government Documents Department

Decontamination testing of radioactive-contaminated stainless steel coupons using a Ce(IV) solution

Description: The current Hanford Waste Vitrification Plant (HWVP) reference process for canister decontamination describes an air-atomized frit/water slurry blaster developed for the Defense Waste Processing Facility (DWPF). Westinghouse Hanford Company (WHC) identified incentives to evaluate potential HWVP cost savings from adapting the Ce(IV)/HNO{sub 3} canister decontamination approach being developed for the West Valley Demonstration Project (WVDP) at West Valley, New York. Development studies were recommended by WHC to address issues related to further assessment of the adaptation of the Ce(IV)/HN0{sub 3} decontamination system to HWVP, and to resolve a number of technical uncertainties. Laboratory studies at the Pacific Northwest Laboratory (PNL) were performed to provide further data to support the selection of an effective flowsheet for the Ce(IV)/HN0{sub 3} decontamination of HWVP stainless steel (SS) vitrification canisters. The results reconfirmed the predictability of this unique chemical milling and decontamination process. The decontamination process developed in the laboratory will be scaled up by a factor of 5,000:1 and tested in FY 1992 by the WVDP at West Valley using uncontaminated full-scale glass-filled canisters. An engineering uncertainty remains to be resolved concerning the removal of a layer of loosely held oxide, some of which may remain on the SS surface after removal of the canister from the decontamination solution. In this laboratory study, low-pressure water from a standard laboratory wash bottle was used to rinse the surfaces of the test coupons. Ultrasonic agitation has been a suggested alternative or addition to spray nozzles for rinsing but has not been selected for the initial series of full-scale tests.
Date: August 1, 1992
Creator: Bray, L. A.; Elmore, M. R.; Carson, K. J.; Elovich, R. J.; Richardson, G. M. & Anderson, L. D.
Partner: UNT Libraries Government Documents Department

Demographic, agricultural products, and food consumption data for a collective farm in Oranoe District, Ivankov District, Kiev Region, Ukraine

Description: This report provides some demographic, agricultural and food consumption data for the collective farms ( Kybisheva,'' composed of three villages) in the Oranoe Department, District of Ivankov, Kiev Region. This area is situated approximately 15 km south of the Chernobyl 30-km Exclusion Zone. The levels of {sup 137}Cs are approximately 5--10 curies/km{sup 2}. This data was collected by the Integrated Radioecological Expedition to Chernobyl of the Russian Academy of Sciences as part of the co-operative studies on environmental radiation dose assessment conducted under the US/USSR Joint Co-operative Committee on Civilian Nuclear Reactor Safety (JCCCNRS) established in 1989.
Date: July 1, 1992
Creator: Ryabov, I N; Davidenko, G M; Templeton, W L & ,
Partner: UNT Libraries Government Documents Department

Hanford radiological protection support services annual report for 1991

Description: Various Hanford sitewide radiation protection services provided by the Pacific Northwest Laboratory for the US Department of Energy, Richland Field Office and Hanford contractors are described In this annual report for calendar year 1991. These activities include internal dosimetry measurements and evaluations, in vivo measurements, external dosimetry measurements and evaluations, instrument calibration and evaluation, radiation source calibration, and radiological records keeping. For each of these activities, the routine program, program changes and enhancements, associated tasks, investigations and studies, and related publications, presentations, and other staff professional activities are discussed as applicable.
Date: July 1, 1992
Creator: Lyon, M.; Bihl, D. E.; Fix, J. J.; Piper, R. K.; Froelich, T. J.; Leonwich, J. A. et al.
Partner: UNT Libraries Government Documents Department

Radionuclide concentrations in white sturgeon from the Columbia River

Description: Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.
Date: September 1, 1992
Creator: Dauble, D. D.; Price, K. R. & Poston, T. M.
Partner: UNT Libraries Government Documents Department

Nuclear research with heavy ions

Description: This report discusses the following topics; studies of light-charged-particle emission from fission and er reactions in the system 344-MeV{sup 28}Si+{sup 121}Sb {yields} {sup 149}Tb; the role of reversed kinematics and double kinematic solutions in nuclear reactions studies; improvements in interactive data analysis and graphical representations; studies of the reaction 856-MeV {sup 98}Mo + {sup 51}V{yields}{sup 149}Tb(E*=224-MeV): emission of intermediate-mass fragments; particle-particle correlations in compound nucleus reactions: preliminary consideration of lifetime estimates from small angle data; light particle emission studies using a new scintillator array; statistical evaporation calculations: developments with the computer codes LILITA-N90 and CASCADE; star collaboration studies: simulations for the conceptual design of the STAR detector system at RHIC; asymmetric fission of 149Tb* from the finite-range, rotating-liquid-drop model: mean total kinetic energies for binary fragmentation; and charged-particle evaporation from hot composite nuclei: evidence over a broad z range for distortions from cold nuclear profiles.
Date: August 1, 1992
Creator: Kaplan, M.
Partner: UNT Libraries Government Documents Department

Summary of the March 25--26, 1991 atmospheric model working meeting

Description: Atmospheric transport and diffusion calculations for the initial phase of the Hanford Environmental Dose Reconstruction (HEDR) Project were made using the MESOILT2 computer code (Ramsdell and Burk 1991). This code implemented a Lagrangian trajectory, puff dispersion model using components from other models designed primarily for regulatory applications. Uncertainty in the dispersion calculations was estimated following model calculations. The results of the atmospheric dispersion calculations were summarized in frequency distributions by location for use in preliminary dose calculations.
Date: July 1, 1992
Creator: Ramsdell, J. V.
Partner: UNT Libraries Government Documents Department

Hydrodynamical calculations of heavy-ion collisions. [Fragment elongation, differential cross sections]

Description: Heavy-ion collisions are studied by the use of two different approaches, depending upon whether the bombarding energy per nucleon yields collective velocities that are small or large compared to the nuclear sound speed. In low energy collisions the primary emphasis is on such fundamental aspects of nuclei as the nuclear potential energy of deformation, the nuclear inertia tensor, and the mechanism for nuclear dissipation. In high energy collisions the primary emphasis is on the nuclear equation of state, the fundamental relation specifying how the pressure depends upon density and internal energy. Some results are shown for differential cross sections and fragment elongation versus distance between mass centers. (JFP)
Date: September 1, 1977
Creator: Amsden, A. A.; Goldhaber, A. S.; Harlow, F. H.; Moeller, P.; Nix, J. R. & Sierk, A. J.
Partner: UNT Libraries Government Documents Department

Removal of radioactive contaminants from aqueous laboratory wastes by chemical treatment

Description: The following conclusions can be drawn from the studies reported. The presence of suspended matter (i.e., clay) in the spiked tapwater solution improved the plutonium removals; however, the addition of clinoptilolite to the plant raw feed did not provide any noticeable improvement for plutonium removal. The addition of powdered clinoptilolite to the regular treatment in the plant significantly improved the removal of /sup 137/Cs, but had little effect on plutonium or /sup 90/Sr removal. Magnesium sulfate-lime-TSP (trisodium phosphate) treatment in the plant performed adequately, but not as well as the regular ferric sulfate-lime-TSP treatment. However, magnesium appears to be an adequate alternate during occasions of non-typical influents. A large portion of the plutonium is associated with the suspended solids matter in the waste. Autoradiographs indicate that the plutonium is generally evenly distributed, with some occasional hot spots.
Date: January 1, 1976
Creator: Drago, J. A. & Buchholz, J. R.
Partner: UNT Libraries Government Documents Department

Radionuclide content of an exhumed canyon vessel and neighboring soil. [Health hazards from long-time buried radiochemical process equipment]

Description: The long-term hazard potential associated with burial of process equipment from radiochemical separations plants is being evaluated. As part of this evaluation, a feed adjustment tank was exhumed eighteen years after burial. The tank had been in service in the fuel reprocessing plant for twenty-nine months before it was retired. Assay of the exhumed tank indicated that 7 mg (0.4 mCi) of /sup 239/Pu and 1 mCi of /sup 137/Cs remained on its surfaces; 1.1 mg (0.07 mCi) /sup 239/Pu, 0.4 mCi /sup 137/Cs, and 3.5 mCi /sup 90/Sr were found in neighboring soil. The vessel and surrounding soil have met the present guidelines (less than or equal to 10 nCi/g) of the U. S. Energy Research and Development Administration (ERDA) for nonretrievable waste.
Date: November 1, 1976
Creator: Holcomb, H. P.
Partner: UNT Libraries Government Documents Department

Radionuclide content of an exhumed canyon tank and neighboring soil

Description: To assess the long-term hazard potential associated with the burial of partially decontaminated process equipment, burial emplacements of equipment from an irradiated-fuel separations building (canyon) are being exhumed and examined. One piece of equipment, a Purex feed adjustment tank that was retired in 1957 from service in a hot canyon at the Savannah River Plant, has been exhumed and studied. This paper describes sampling of neighboring soil, tank exhumation, results of assay of soil and tank, and conclusions. Assays of the tank and soil show that only 1 mCi of /sup 137/Cs and 0.4 mCi (7 mg) of /sup 239/Pu remain on the surfaces of the tank; amounts of these radionuclides in neighboring soil are substantially less. Radionuclides from the contaminated surface of the tank migrated into neighboring soil. Of the three nuclides studied, /sup 90/Sr migrated most extensively, as observed previously. /sup 239/Pu contents of the tank and neighboring soil were less than the 10-nCi/g total transuranic nuclide content allowed under ERDA standards for burial of nonretrievable waste. This paper also describes plans for future studies including (1) exhumation of other equipment and (2) in-place lysimeter and laboratory-column tests for studying radionuclidic migration in soil.
Date: January 1, 1977
Creator: Holcomb, H. P.
Partner: UNT Libraries Government Documents Department

Growth and characterization of isotopically enriched [sup 70]Ge and [sup 74]Ge single crystals

Description: Isotopically enriched [sup 70]Ge and [sup 74]Ge single crystals were successfully gown by a newly developed vertical Bridgman method. The system allows us to reliably grow high purity Ge single crystals of approximately 1 cm[sup 3] volume. To our knowledge, we have grown the first [sup 70]Ge single crystal. The electrically active chemical impurity concentration for both crystals was found to be [approximately]2 [times] cm[sup [minus]3] which is two order of magnitude better that of [sup 74]Ge crystals previously grown by two different groups. Isotopic enrichment of the [sup 70]Ge and the [sup 74]Ge crystals is 96.3% and 96.8%, respectively. The residual chemical impurities present in both crystals were identified as phosphorus, copper, aluminum, and indium. A wide variety of experiments which take advantage of the isotopic purity of our crystals are discussed.
Date: October 1, 1992
Creator: Itoh, K.
Partner: UNT Libraries Government Documents Department

Great Lakes waters: radiation dose commitments, potential health effects, and cost-benefit considerations

Description: In 1972, a Great Lakes Water Quality Agreement was signed by the United States and Canadian Governments. It was stipulated that the operation and effectiveness of the agreement were to be reviewed comprehensively in 1977. Aspects of the agreement concern nondegradation of Great Lakes waters and maintenance of levels of radioactivity or other potential pollutants at levels considered as low as practicable. A refined radioactivity objective of one millirem is proposed in the Water Quality Agreement. The implications of adoption of this objective are not known fully. The Division of Environmental Impact Studies was commissioned by ERDA's Division of Technology Overview to summarize the information available on the current levels of radioactivity in Great Lakes waters, compute radiation-dose commitment (integrated dose over 50 years after consumption of 2.2 liters of water of one year), and to comment on the feasibility and cost-benefit considerations associated with the refined one-millirem objective. Current levels of radioactivity in the waters of Lakes Michigan, Ontario, Erie, and Huron result in dose commitments in excess of 1 mrem for whole body and 6 mrem for bone. Future projections of isotope concentrations in Great lakes water indicate similar dose commitments for drinking water in the year 2050. Reduction of the levels of radioactivity in Great Lakes waters is not feasible, but cost-benefit considerations support removal of /sup 226/Ra and /sup 90/Sr through interceptive technology before water consumption. Adoption of the one-millirem objective is not propitious.
Date: July 1, 1977
Creator: Ainsworth, E. J.
Partner: UNT Libraries Government Documents Department

Effects of interstitial solutes on the microstructures of self-ion irradiated vanadium

Description: Vanadium and vanadium containing 0.1 percent C, 0.4 percent C, 1.0 percent N, and 1.0 percent O were irradiated with 3-MeV /sup 51/V/sup +/ ions in the temperature range 650 to 880/sup 0/C to a dose level of approximately 20 dpa. The results show that nitrogen is most effective in controlling the void swelling. Carbon and oxygen also suppress the swelling considerably when compared with unalloyed vanadium. Except for V-1.0 percent N, all compositions exhibit a fine platelet precipitate with (012) habit at 650/sup 0/C. In the case of vanadium-carbon alloys, this phase persisted even at higher temperatures. Vanadium and V-1.0 percent O showed fine precipitation on dislocations and void surfaces at 880/sup 0/C. V-0.1 percent C exhibited a metastable (013) carbide precipitate at 880/sup 0/C, whereas V-0.4 percent C showed equilibrium V/sub 2/C phase with some (012) precipitates. This (012) precipitation was irradiation induced and was dependent upon the carbon concentration. V-1.0 percent N did not show any evidence of precipitation over the entire temperature range.
Date: January 1, 1976
Creator: Agarwal, S. C.; Potter, D. I. & Taylor, A.
Partner: UNT Libraries Government Documents Department

Optical theorem for heavy-ion scattering. [Scattering amplitudes, cross sections]

Description: An heuristic derivation is given of an equivalent of the optical theorem stated in the charged situation with the remainder or nuclear elastic scattering amplitude defined as a difference of elastic and Coulomb amplitudes. To test the detailed behavior of this elastic scattering amplitude and the cross section, calculations were performed for elastic scattering of /sup 18/O + /sup 58/Ni, /sup 136/Xe + /sup 209/Bi, /sup 84/Kr + /sup 208/Pb, and /sup 11/B + /sup 26/Mg at 63.42 to 114 MeV. (JFP)
Date: January 1, 1976
Creator: Schwarzschild, A. Z.; Auerbach, E. H.; Fuller, R. C. & Kahana, S.
Partner: UNT Libraries Government Documents Department