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Evaluation of uncertainties in irradiated hardware characterization: Final report, September 30, 1986-March 31, 1987

Description: Waste Management Group, Inc. has evaluated the techniques used by industry to characterize and classify irradiated hardware components for disposal. This report describes the current practices used to characterize the radionuclide content of hardware components, identifies the uncertainties associated with the techniques and practices considered, and recommends areas for improvement which could reduce uncertainty. Industry uses two different characterization methods. The first uses a combination of gamma scanning, direct sampling, underwater radiation profiling and radiochemical analysis to determine radionuclide content, while the second uses a form of activation analysis in conjunction with underwater radiation profiling. Both methods employ the determination of Cobalt 60 content, and the determination of scaling factors for hard-to-detect Part 61 radionuclides. The accurate determination of Cobalt-60 is critical since the Part 61 activation product radionuclides which affect Part 61 classification are scaled from Cobalt-60. Current uncertainties in Cobalt-60 determination can be reduced by improving underwater radiation profiling equipment and techniques. The calculational techniques used for activation analysis can also be refined to reduce the uncertainties with Cobalt-60 determination. 33 refs., 11 figs., 10 tabs.
Date: October 1, 1987
Creator: Bedore, N.; Levin, A. & Tuite, P.
Partner: UNT Libraries Government Documents Department

Atmospheric releases from severe nuclear accidents: Environmental transport and pathways to man: Modelling of radiation doses to man from Chernobyl releases

Description: The Chernobyl accident released a large amount of highly fractionated radioactive debris, including approximately 89 PBq of /sup 137/Cs. We calculated the resulting collective dose commitment to the Northern Hemisphere via the pathways of external exposure and ingestion of radionuclides withd food. We developed a rural/urban model of external dose and we used the PATHWAY model for ingestion. The results are a collective dose commitment of 630,000 person-Gy over the first year and 1,200,000 person-Gy over 50 years. 13 refs., 1 tab.
Date: January 1, 1987
Creator: Anspaugh, L.R.; Goldman, M. & Catlin, R.J.
Partner: UNT Libraries Government Documents Department

M1 transitions between collective levels and F-spin purity

Description: M1 transitions between low-lying collective levels in deformed nuclei are described within the IBM-2 framework. This is done by a special choice of the Hamiltonian which allows a simultaneous fit of energies, E2 and M1 transitions. Finally, the results are interpreted using the F-spin concept. 12 refs., 4 tabs.
Date: January 1, 1987
Creator: von Brentano, P.; Frank, W.; Gelberg, A.; Harter, H.; Krips, W.; Casten, R.F. et al.
Partner: UNT Libraries Government Documents Department

Calculated late time spectra of supernovae

Description: We consider here the nebular phase spectra of supernovae whose late time luminosity is provided by the radioactive decay of /sup 56/Ni and /sup 56/Co synthesized in the explosion. A broad variety of supernovae are known or suspected to fall in this category. This includes all SNIa and SNIb, and at least some SNII, in particular SN1987a. At sufficiently late times the expanding supernova becomes basically nebular in character due to its decreasing optical depth. The spectra produced during this stage contain information on the density and abundance structure of the entire supernova, as opposed to spectra near maximum light which are affected only by the outermost layers. A numerical model for nebular spectrum formation is therefore potentially very valuable for answering currently outstanding questions about the post-explosion supernova structure. As an example, we can hope to determine the degree of mixing which occurs between the layers of the ''onion-skin'' abundance structure predicted by current one dimensional explosion calculations. In the sections which follow, such a numerical model is briefly described and then applied to SN1972e, a typical SNIa, SN1985f, an SNIb, and finally to SN1987a. In the case of SN1987a predicted spectra are presented for the wavelength range from 1 to 100 microns at a time 300 days after explosion. 18 refs., 6 figs.
Date: October 30, 1987
Creator: Axelrod, T.S.
Partner: UNT Libraries Government Documents Department

Radiation effects in space

Description: As more people spend more time in space, and the return to the moon and exploratory missions are considered, the risks require continuing examination. The effects of microgravity and radiation are two potential risks in space. These risks increase with increasing mission duration. This document considers the risk of radiation effects in space workers and explorers. 17 refs., 1 fig., 4 tabs.
Date: July 1, 1987
Creator: Fry, R.J.M.
Partner: UNT Libraries Government Documents Department

Radioactive fallout from the Chernobyl nuclear reactor accident

Description: This report describes the detection of fallout in the United States from the Chernobyl nuclear reactor accident. As part of its environmental surveillance program, Lawrence Livermore National Laboratory maintained detectors for gamma-emitting radionuclides. Following the reactor accident, additional air filters were set out. Several uncommon isotopes were detected at the time the plume passed into the US. (TEM)
Date: August 1, 1987
Creator: Beiriger, J.M.; Failor, R.A.; Marsh, K.V. & Shaw, G.E.
Partner: UNT Libraries Government Documents Department

Radioactivity in persons exposed to fallout from the Chernobyl reactor accident

Description: Measurements of fallout radioactivity were made in the thyroid region, abdomen, whole body, or urine of 96 persons who were in eastern Europe at the time of the Chernobyl reactor accident or who went there shortly afterward. The most frequently encountered radionuclides were /sup 131/I, sup 134,137/Cs, and /sup 103/Ru//sup 103/Rh. The median /sup 131/I activity in the thyroids of 42 subjects in whom radioiodine was detected and who were in Europe when the accident began was projected as 42 nCi the day the accident began. The median total body activity of /sup 134/Cs in 40 subjects in which it was detected was 1.7 nCi upon arrival in the US. For 51 subjects with detectable /sup 137/Cs burdens, the total body activity was 4.6 nCi. The risk of fatal thyroid cancer is less than 3 x 10/sup -6/ for nearly all subjects in this series. The risk of fatal cancer from /sup 134,137/Cs for subjects with cesium exposures similar to the ones observed by us, but who remained in Europe, is estimated as 1.4 x 10/sup -6/ to 4.2 x 10/sup -5/ with 95% of the risk attributable to /sup 137/Cs. 5 refs., 4 tabs.
Date: January 1, 1987
Creator: Schlenker, R.A.; Oltman, B.G. & Lucas, H.F.
Partner: UNT Libraries Government Documents Department

Internally deposited fallout from the Chernobyl reactor accident

Description: Measurements of fallout radioactivity were made in the thyroid region, abdomen, whole body, or urine of 96 persons who were in eastern Europe at the time of the Chernobyl reactor accident or who went there shortly afterward. The most frequently encountered radionuclides were /sup 131/I, /sup 134,137/Cs, and /sup 103/Ru//sup 103/Rh. The median /sup 131/I activity in the thyroids of 42 subjects in whom radioiodine was detected and who were in Europe when the accident began was projected as 42 nCi the day the accident began. The median total body activity of /sup 134/Cs in 40 subjects in which it was detected was 1.7 nCi upon arrival in the US. For 51 subjects with detectable /sup 137/Cs burdens, the total body activity was 4.6 nCi. The risk of fatal thyroid cancer is less than 3 x 10/sup -6/ for nearly all subjects in this series. The risk of fatal cancer from /sup 134,137/Cs for subjects with cesium exposures similar to the ones observed by us, but who remained in Europe, is estimated as 1.4 x 10/sup -6/ to 4.2 x 10/sup -5/ with 95% of the risk attributable to /sup 137/Cs. 5 refs., 4 tabs.
Date: January 1, 1987
Creator: Schlenker, R.A.; Oltman, B.G. & Lucas, H.F.
Partner: UNT Libraries Government Documents Department

Transmission-corrected x-ray fluorescence analysis of uranium and plutonium solutions using a dual transmission source

Description: The energy-dispersive x-ray fluorescence analysis (XRFA) technique has been implemented at several spent nuclear fuel reprocessing facilities for nondestructive measurements of uranium and/or plutonium concentrations in process streams and product storage tanks. An important factor in these quantitative measurements is the absorption of the fluoresced x-rays by the solution matrix, which must be taken into account to accurately quantify the U or Pu concentrations. We describe a new, accurate method using a dual transmission source of Gd-153 and Co-57 to correct for matrix effects. Results of measurements on uranium and plutonium solution standards show the methodology to be better than 0.5%, which includes statistical precision, over the concentration range from 1 to 250 g/l. 5 refs., 4 figs., 3 tabs.
Date: November 24, 1987
Creator: Ruhter, W.D. & Camp, D.C.
Partner: UNT Libraries Government Documents Department

The Moessbauer effect of SnI/sub 4/ at high pressures

Description: Tetravalent tin iodide is a molecular crystal composed of SnI/sub 4/ tetrahedra loosely packed into a cubic configuration. Under pressure SnI/sub 4/ becomes metallic at about 15 GPa. We report a Moessbauer effect study of /sup 119/Sn and /sup 129/I in SnI/sub 4/ to pressures of 26 GPa. The spectra exhibit dramatic changes with pressure starting at about 10 GPa and show large pressure hysteresis effects upon reducing the pressure from 26 GPa. In the intermediate region tin exists in both Sn/sup 4 +/ and Sn/sup 2 +/ states, and iodine exists in two nonequivalent sites characterized by a different symmetry and different sign and magnitude of the electric field gradient. 11 refs., 6 figs.
Date: January 1, 1987
Creator: Taylor, R.D.; Pasternak, M. & Farrell, J.N.
Partner: UNT Libraries Government Documents Department

Fabrication of isotopic heat and radiation sources for the Federal Republic of Germany

Description: Pacific Northwest Laboratory (PNL) has filled 30 German-made canisters with highly radioactive borosilicate glass. These canisters, containing specified amounts of /sup 137/Cs and /sup 90/Sr, will be sealed using a gas tungsten arc welder and will be decontaminated to nonsmearable limits using an electropolishing system. They are to be characterized in a series of nondestructive tests: surface dose rate measurement, axial gamma scanning, canister mass determination, and canister surface temperature measurement. The canisters will then be transported to the Asse Salt Mine located in the Federal Republic of Germany (FRG) for a 5-year repository testing program. 3 refs., 2 figs., 1 tab.
Date: September 1, 1987
Creator: McElroy, J.L.; Holton, L.K. Jr.; Burkholder, H.C.; Bryan, G.H. & Minor, J.E.
Partner: UNT Libraries Government Documents Department

Review of radial dose profiles for heavy ions

Description: Average energy deposited per unit mass in a cylindrical shell formed between radial distance r and r + dr from the trajectory of incident ions is defined as the radial dose D(r). Variation of D(r) as a function of radial distance is the radial dose profile. This radial dose profile information has been used by others to develop biophysical models of radiation effects. Radial dose profiles for heavy ions also provide data that can be checked against calculations made by different track structure codes based on continuous slowing down models or Monte Carlo methods. In addition radial dose profiles can also be determined from measured event size distributions. By comparing radial dose from two different experimental techniques, a direct evaluation of different experimental procedures and methods can be made. In this document we review the experimental measurement technique for determination of radial dose profiles, and the experimental data available for different heavy ions at different energies. 15 refs., 5 figs.
Date: January 1, 1987
Creator: Varma, M.N. & Baum, J.W.
Partner: UNT Libraries Government Documents Department

Effects of calmodulin inhibitors on the cellular metabolism of /sup 45/Ca and /sup 210/Pb

Description: Altered Ca/sup + +/ homeostasis may result from the direct inhibition of calmodulin-dependent or -independent transport processes. Changes in cell function not directly related to the transport of Ca, e.g., uncoupling of oxidative phosphorylation or altered membrane permeability also disrupt cell calcium metabolism. Thus, the effects of the calmodulin inhibitor W-13 on cell Pb/sup + +/ metabolism may be due to its direct effects on Pb/sup + +/ transporting Ca/sup + +/ pumps, or indirectly as a result of changes in Ca/sup + +/ homeostasis. Direct comparison of the effects of W-13 on the metabolism of Pb and Ca is impaired by differences in the kinetic distribution and behavior of Pb and Ca. A further complication is that the calmodulin-dependent processes are most active during periods of elevated intracellular Ca/sup + +/. The preliminary experiments reported here were conducted in unstimulated cells which have a low resting level of cytosolic Ca/sup + +/. Therefore, W-13 induced alterations in cell Ca/sup + +/ and Pb/sup + +/ may not reflect the changes which could occur in stimulated cells. 1 ref., 1 fig.
Date: January 1, 1987
Creator: Pounds, J.G. & Nye, A.C.
Partner: UNT Libraries Government Documents Department

Lactation-induced cadmium-binding proteins

Description: Previously we have demonstrated an increase during midlactation in /sup 109/Cd adsorption and increased retention by the duodenum, kidney, and mammary tissue of mouse dams receiving environmental levels of cadmium//sup 109/Cd via drinking water, with little change in /sup 109/Cd retention in liver and jejunum compared to nonpregnant controls. Results are reported here of a study of cadmium deposition during midlactation as associated with induction of metallothionein (MT). A cadmium/hemoglobin (Cd/Hb) assay and radioimmunoassay for MT which measures heat-stable cadmium binding capacity in tissues was used to determine MT concentrations in fractions of kidney, liver, duodenum, and jejunum from female mice. Both assays demonstrated clear lactation-induced increases in MT concentrations in liver, kidney, and duodenum, with MT concentrations falling rapidly to control levels after weaning. 4 refs., 1 tab.
Date: January 1, 1987
Creator: Bhattacharyya, M.H.; Solaiman, D.; Garvey, J.S. & Miyazaki, W.Y.
Partner: UNT Libraries Government Documents Department

Pion charge exchange and nuclear structure: II, Nuclear structure calculation

Description: Whereas the nuclear charge distribution, essentially determined by the protons, has been studied for decades in elastic electron scattering, a study of the neutron distribution in nuclei has only recently become possible through pion charge-exchange experiments. The excitation of the isobaric analog state (IAS) in pion single-charge-exchange reactions is one of the most prominent candidates for such an investigation which will be especially interesting for strongly deformed nuclei which can be aligned in magnetic fields. This contribution concentrates on calculations related to such a reaction for the rare-earth nucleus Ho-165. 8 refs., 3 figs.
Date: January 1, 1987
Creator: Bartel, J.; Johnson, M.B. & Singham, M.
Partner: UNT Libraries Government Documents Department

Internally deposited fallout from the Chernobyl reactor accident

Description: In our work with about 100 subjects resident in eastern Europe (mostly Poland) at the time of the Chernobyl reactor accident or traveling as tourists, /sup 131/I was readily detectable in the thyroid through mid-June, 1986, and was detectable in some subjects as late as early July, 9 to 10 weeks after the start of the accident. Among 42 subjects who were in eastern Europe on April 26, 1986, and in whom /sup 131/I was detectable, the median activity in the thyroid was 1.4 nCi at the time of measurement. When extrapolated back to April 26 using a single exponential retention function for the thyroid and an 8-day effective half-life, the median activity was 42 nCi. The frequency distribution resembled a lognormal distribution. The extrapolated activities lay between approximately 2 and 1200 nCi. The risk levels derived from these observations of internal radioactivity and my conservative dose projection assumptions are as much as 10 times less than the risk levels published in the lay press during the months following the accident. This underscores the importance of basing risk estimation for internal radioactivity on direct observations. 2 refs., 1 tab.
Date: January 1, 1987
Creator: Schlenker, R.A.
Partner: UNT Libraries Government Documents Department

Dipole strength functions in the actinide mass region

Description: We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.
Date: July 15, 1987
Creator: Gardner, D.G.; Gardner, M.A. & Hoff, R.W.
Partner: UNT Libraries Government Documents Department

Extension of nuclear structure data base searches for gamma-ray laser candidates

Description: Results from a data base search of computerized nuclear structure libraries have been extended and augmented so as to expand the information available for nuclei suitable as gamma-ray laser candidates. The spectrum of nuclear levels occurring in deformed rotational nuclei have been calculated and have been used in conjunction with isomeric state data for odd-A systems. The results of this augmentation effort are presented with particular emphasis on results obtained for /sup 177/Lu, /sup 177/Hf, and /sup 179/Hf. For these cases some possibly interesting cases were identified that met energy spacing criteria. However, significant hindrance factors exist for them which negate their interest for gamma-ray laser applications. 9 refs., 1 fig., 1 tab.
Date: December 1, 1987
Creator: Arthur, E.D.; Madland, D.G. & George, D.C.
Partner: UNT Libraries Government Documents Department

Performance of the Soudan II honeycomb drift chambers

Description: The Soudan II nucleon decay project is in the process of building 260 identical 5-ton fine grained calorimeter modules for the study of nucleon decay and cosmic ray physics in the Soudan Iron Mine in Minnesota. Several of these modules have been studied on a cosmic ray test stand on the surface at Argonne National Lab. Several have been installed on location in the mine, 700 m under the surface (2200 mwe overburden). In addition, many studies of trigger efficiency, pattern recognition and background rejection have been done using Monte Carlo techniques.
Date: January 1, 1987
Creator: Ambats, I.; Ayres, D.; Barrett, W.; Dawson, J.; Fields, T.; Goodman, M.C. et al.
Partner: UNT Libraries Government Documents Department

A study of the structure of /sup 162/Dy through the (n,. gamma. ) and (n,e/sup -/) reactions

Description: The level structure below 2 MeV in /sup 162/Dy has been investigated using the /sup 161/Dy(n,..gamma..)/sup 162/Dy and /sup 161/Dy(n,e/sup -/)/sup 162/Dy reactions. The results for the positive parity excitations are discussed within the framework of an Interacting Boson Approximation (IBA-2) calculation. 7 refs., 1 fig., 1 tab.
Date: January 1, 1987
Creator: Warner, D.D.; Shi, Z.R.; Gelletly, W.; Borner, H.G.; Hoyler, F.; Schreckenbach, K. et al.
Partner: UNT Libraries Government Documents Department

Energy levels and structure of light rare-earth nuclei, /sup 136,138,140/Sm and /sup 132,134,136/Nd, via beta decay

Description: Levels in /sup 136,138,140/Sm were populated by the beta decay of Eu, following (HI,pxn) reactions and on-line mass separation. Members of the ..gamma.. band were observed in all three daughter nuclei. Spectroscopic calculations were made using the triaxial rotor model, with all parameters derived microscopically from a Woods-Saxon deformed shell model. Comparison with the data supports the characterization of these nuclei in terms of a triaxial intrinsic shape. Improved decay schemes for /sup 132,134,136/Nd are given. 3 refs., 7 figs.
Date: January 1, 1987
Creator: Kern, B.D.; Leander, G.A.; Mlekodaj, R.L.; Carter, H.K.; Kortelahti, M.O.; Zganjar, E.F. et al.
Partner: UNT Libraries Government Documents Department

Radioactivities with 146 less than or equal toA less than or equal to152 investigated at the OASIS facility: Evidence for /sup 147/Tm. beta. -decay

Description: Progress is reported for a collaborative program, involving researchers from the Lawrence Berkeley and Oak Ridge National Laboratories, which has now been in progress at the SuperHILAC OASIS on-line facility for more than two years. In these investigations properties of short lived nuclei near the N = 82 neutron shell have been studied, their decays being assayed with particle, gamma ray, x ray, and positron detectors. Nuclides investigated so far were produced in /sup 58/Ni bombardments of /sup 96/Ru, /sup 94/Mo, and /sup 92/Mo. The focus of the study has been primarily two-fold: (1) to gain insight into the nature of the sharp peaks seen in the delayed proton spectra that accompany the beta decays of N = 81 even Z precursors, and (2) to investigate low lying states in nuclei near N = 82, levels whose structures should be describable by shell model analyses. 9 refs., 2 figs. (DWL)
Date: January 1, 1987
Creator: Toth, K.S.; Nitschke, J.M.; Wilmarth, P.A.; Ellis-Akovali, Y.A.; Sousa, D.C.; Vierinen, K. et al.
Partner: UNT Libraries Government Documents Department

On-Line Measurement of Stack-Gas Particulate Radionuclides

Description: This paper describes an advanced process-monitoring system for the automatic sample collection, analysis, reporting, and alarming of the concentration of long-lived radionuclides in nuclear process stack-gas effluents. This system, the Moving Filter Radioactive Aerosol Monitor, collects particulates in a conditioned sampling chamber, under computer control, for subsequent and separate alpha and beta counting and analysis. The alpha measurement is performed with a solid-state surface-barrier detector. Beta analysis is performed with a phoswich scintillation detector. A unique alpha-energy analysis program that provides automatic energy calibration and lowered detection limits for plutonium in the presence of high quantities of interfering /sup 212/Bi/Po is described. The /sup 212/Bi/Po alpha results are further used to monitor system quality and to compensate for the radon daughter beta components in the beta system. Results of the system calibration and detection limits are also presented. 8 refs., 6 figs.
Date: November 1987
Creator: Stong, F. S.; Troyer, G. L. & Criddle, J. D., Jr.
Partner: UNT Libraries Government Documents Department