221 Matching Results

Search Results

Advanced search parameters have been applied.

Nuclear chemistry progress report. [Physics Department, Princeton University]

Description: Research in the physics department at Princeton University is reviewed briefly. Results on the Coulomb capture of negative muons by the binary alloy systems Cu/Al and Ag/Zn show that (within experimental error) there is no change in the per atom ..mu../sup -/ capture probability when the atomic ratio in these alloys varies over a range of approximately 40. The K muonic x-ray intensity pattern observed from ..mu.. capture in atmospheric N/sub 2/ was strikingly different from that observed when ..mu.. is captured by N atoms in a condensed phase; this difference was interpreted in terms of differing states of ionization during the capture cascade. The (p,t) reaction was used to study states in /sup 203/Pb, /sup 189/Ir, /sup 191/Ir, and /sup 174/Lu. Triton energy spectra are shown, along with an energy-level diagram of the states deduced in /sup 174/Lu. 13 figures, 6 tables. (RWR)
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

Oceanic distributions of radionuclides from nuclear weapons testing. [Relevance to decision as to marine disposal of radioactive wastes]

Description: Data on the transport of fallout radionuclides in the Atlantic and Pacific Oceans are reviewed. Relevance of water column fallout data to the disposal of radioactive waste in marine locations is discussed. It is pointed out that regional patterns of delivery of soluble radionuclides must be assumed to persist at least for decades, in spite of the homogenizing action of ocean current systems and that, although there are delays in relation to density discontinuities in the water column, particle-associated radionuclides are generally delivered directly to the sediment surface. The chemistry of particle association appears increasingly complex, in relation both to the element selectivity among kinds of particles, and the stability of the associations once formed, and regional conditions may lead to retention of Pu (and possibly other nuclides) in discrete layers or throughout the water column, in opposition to its general tendency to associate with particles.
Date: January 1, 1977
Creator: Bowen, V.T.
Partner: UNT Libraries Government Documents Department

Plutonium and americium concentration along fresh-water food chains of the Great Lakes, U. S. A. Progress report, July 1976--September 30, 1977

Description: The primary purpose of studying the biogeochemical behavior of transuranic radionuclides in large freshwater lakes began with studies of the distribution of these radionuclides, essentially introduced from the fallout of atmospheric nuclear weapons tests, in Lake Ontario. The recognition that an additional source of supply of these nuclides to Lake Ontario (subsequent to their release into Lake Erie) existed in the form of leakage from the Nuclear Fuel Services reprocessing plant at Springville, New York, led to expansion of the program to include sampling at the eastern end of Lake Erie. Much of the program is devoted to studies of the distribution of these nuclides in the lake sediments as they appear to be a major repository for transuranics in freshwater lakes. The extent to which this is a temporary or permanent repository is illuminated by studies of transuranic distributions in the lake waters and biota.
Date: January 1, 1977
Creator: Bowen, V.T.
Partner: UNT Libraries Government Documents Department

Plutonium and cesium radionuclides in the Hudson River estuary. Annual technical progress report, December 1, 1976--November 30, 1977

Description: We have obtained a large set of sediment cores from the Hudson estuary through much of the ambient salinity range. A number of core sections and samples of suspended particles have been analyzed for /sup 137/Cs, /sup 134/Cs and /sup 60/Co by direct gamma counting, and /sup 239/Pu, /sup 240/Pu, and /sup 238/Pu by alpha spectrometry. The distribution of both /sup 137/Cs and /sup 239/Pu, /sup 240/Pu indicates rapid accumulation in marginal cover areas, and especially in the harbor region adjacent to New York City. The distributions of both /sup 137/Cs and /sup 239/Pu, /sup 240/Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to addition of reactor /sup 137/Cs and loss of /sup 137/Cs from the particle phases at higher salinities. Measureable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly all sediment samples containing appreciable /sup 137/Cs, between 15 km upstream of Indian Point and the downstream extent of our sampling, 70 km south of the reactor. Accumulations of /sup 239/Pu, /sup 240/Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate. The most likely explanation is accumulation of fine particles in the harbor which have been transported from upstream areas of the Hudson. Our evidence so far indicates that Indian Point is probably not a significant source of /sup 239/Pu, /sup 240/Pu or /sup 238/Pu compared with the fallout burden of these nuclides already in the sediments.
Date: January 1, 1977
Creator: Simpson, H. J. & Trier, R. M.
Partner: UNT Libraries Government Documents Department

Quarterly report on the strontium heat source development program and the beneficial isotopes utilization program, Division of Nuclear Research and Application for October--December 1976. [WESF capsules]

Description: At Hanford, strontium is separated from the high-level waste, converted to the fluoride, and doubly encapsulated in small, high-integrity containers for subsequent long-term storage. The fluoride conversion, encapsulation and storage take place in the Waste Encapsulation and Storage Facilities (WESF). The encapsulated strontium fluoride represents an economical source of /sup 90/Sr if the WESF capsule can be licensed for heat source applications under anticipated use conditions. The objectives of this program are to obtain the data needed to license /sup 90/SrF/sub 2/ heat sources and specifically the WESF /sup 90/SrF/sub 2/ capsules. Research progress is reported on: (1) chemical and physical properties of /sup 90/SrF/sub 2/; (2) /sup 90/SrF/sub 2/ compatibility studies; and (3) capsule qualification and licensing. In the Beneficial Isotopes Utilization Program research progress is reported on isotopes availability, cold regions applications, WESF product utilization, and general applications of radioisotopes in army thermal systems. (TFD)
Date: January 1, 1977
Creator: Fullam, H. T. & Jarrett, J. H.
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

Safety and Environmental Protection Division. Progress report, January 1, 1974--December 31, 1975. [Radionuclides in Bikini foods during 1974 and 1975 and environmental monitoring data for BNL during 1975]

Description: Progress is reported in the analysis of food chain samples collected during 1974 and 1975 at the Bikini Atoll in the Marshall Islands for /sup 90/Sr, /sup 137/Cs, /sup 239/Pu, /sup 240/Pu, and /sup 241/Am remaining in the environment from the 1946-1958 nuclear tests. Data on levels of radioactivity in environmental samples and SO/sub 2/ and NO/sub x/ in air samples collected in the vicinity of Brookhaven National Laboratory during 1975 are reported. Samples of surface air, surface waters, ground water, sediments and biota from streams, soils, grass, and milk were analyzed. Abstracts of papers published during 1974 and 1975 are included. (CH)
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

Shell-model origins of collective effects in light- and medium-weight nuclei. [Preliminary results]

Description: Two independent investigations are discussed illustrating possible interesting collective features in some f-p shell nuclei which are generated from the motion of valence nuclei and that the structure of the states in question is consistent with interacting boson model theory. Also further studies of shell-model wave functions in the s-d and light f-p shell nuclei are discussed which also offer some support to the studied model. It is emphasized that these results are preliminary. Nine references. (JFP)
Date: January 1, 1977
Creator: McGrory, J.B.
Partner: UNT Libraries Government Documents Department

Some recent aspects of relaxation line shapes in Moessbauer spectroscopy. [White noise approximation]

Description: Theoretical development in the line shape calculation of Mossbauer resonance spectra involving spin relaxation effects is introduced. The ''eigenvalue'' procedure of calculating line shapes saves computational times by two orders of magnitude compared to traditional methods. This was illustrated by calculating the relaxation spectra of hemoglobin cyanide and a GAMMA/sub 8/ quartet electronic state. The ''white noise approximation'' involved in all the relaxation theory is discussed, and its limitations are pointed out. The theory without such an approximation is used to analyze the data for Cs/sub 2/NaYbCl/sub 6/.
Date: January 1, 1977
Creator: Shenoy, G. K. & Dunlap, B. D.
Partner: UNT Libraries Government Documents Department

Studies of /sup 12/Be and other off-stability nuclei

Description: In collaboration with the Tandem Van de Graaff staff at the University of Pennsylvania the reaction /sup 10/Be(t,p)/sup 12/Be at E/sub t/ = 12 MeV has been used to study the properties of /sup 12/Be. The first excited state of /sup 12/Be has been found to lie at 2.110 +- 0.015 MeV and to have J = 2 from p,..gamma.. angular correlation measurements. Using a chopped beam the search for delayed neutrons from the decay of /sup 12/Be was negative. However, the decay curve for ..beta.. rays can be fitted only if a half-life component of about 25 msec for /sup 12/Be is included along with the activities /sup 12/B, /sup 9/Li, and /sup 8/Li known to be present. A review of the search for new T/sub z/ = +5/2 isotopes in the s-d shell at the Brookhaven Tandem Van de Graaff is presented and recent results on the T/sub z/ = +3 nucleus /sup 34/Si, formed in the /sup 18/O(/sup 18/O,2p)/sup 34/Si reaction, are outlined. Utilizing new ion-source techniques to form a beam of /sup 9/Be ions the reaction /sup 48/Ca(/sup 9/Be,pn)/sup 55/V has been used to find and study the new isotope /sup 55/V of 6 sec half-life. The extension of these techniques to higher Z may be possible although recent studies of heavy-ion reactions indicate that the cross sections may be very small.
Date: January 1, 1977
Creator: Alburger, D.E.
Partner: UNT Libraries Government Documents Department

Study of the proton pairing vibrations as an example of elementary nuclear modes. [Z = 40, 50, 82]

Description: A study of the proton pairing vibrations as an example of elementary nuclear modes is discussed. The (/sup 3/He,n) reaction has been used to study 0/sup +/ proton pair vibration modes for nuclei at Z = 40, 50 and 82. Evidence is presented that Z = 38 is a better shell closure than Z = 40 but not at all perfect. For Z = 50 and 82 correction must be made for the substantial particle hole interaction to obtain agreement with the pairing vibration model. The interaction with neutron pairing quanta is rather small in all cases.
Date: January 1, 1977
Creator: Lind, D.A.
Partner: UNT Libraries Government Documents Department

/sup 122/Xe--/sup 122/I generator: a preliminary report

Description: A generator system is developed to produce the ultrashort-lived positron-emitter iodine-122 (3.62 m) from its parent xenon-122 (20.1 h). The parent xenon-122 can be produced as a by-product in the production of xenon-123 from proton irradiation of sodium iodide target. The generator consists of a xenon reservoir chamber and an ingrowth or milking chamber. The sequence of operation involves transferring xenon using liquid nitrogen from the reservoir to the milking vessel, allowing fresh iodine-122 to grow in for a few minutes, transferring the xenon back to the storage reservoir, and then rapidly rinsing the iodine out of the milking vessel. The radionuclidic purity of the carrier-free iodine-122 is high, containing less than 0.1 percent radioxenons and other radioiodines. The potential applications of iodine-122 include cardiac and large vessel angiography and studying heart dynamics. It is also well suited for use in positron-emission tomography.
Date: January 1, 1977
Creator: Richards, P. & Ku, T.
Partner: UNT Libraries Government Documents Department

Treatment of hyperthyroidism: use of /sup 131/I and /sup 125/I

Description: Factors related to late hypothyroidism following the use of /sup 131/I for treatment of hyperthyroidism are discussed with regard to age of patient, size of dose, previous surgery, immune status, and others. Possible reasons for the post-therapeutic hypothyroidism are discussed with regard to effects of radiation on the reproductive capacity of thyroid cells, effects of radiation on blood vessels, and dose distribution of radioiodine. The following therapeutic strategies are discussed: reduction of initial dose; multiple small doses; high dose radioiodine followed by replacement therapy; the use of external beam irradiation; and the use of /sup 125/I. (HLW)
Date: January 1, 1977
Creator: Atkins, H. L.
Partner: UNT Libraries Government Documents Department

Tumbleweed and cheatgrass uptake of /sup 99/Tc from five Hanford soils. [/sup 95m/Tc tracer]

Description: The accumulation of technetium (Tc) by tumbleweed and cheatgrass was measured for five Hanford Project soils at the initial soil concentration of 1.0 pg/g of /sup 99/Tc traced by /sup 95m/Tc at one, two, and three months' harvest times. Tc was added to the soil as pertechnetate, the chemical form likely to predominate in aerobic terrestrial environments. Uptake of Tc at the three months' harvest time ranged from 23 to 82 percent and 10 to 69 percent of the added Tc for tumbleweed and cheatgrass species, respectively. The soil order of percent uptake by tumbleweed was Lickskillet < Burbank < Rupert < Warden < Ritzville. Shoot concentrations of /sup 99/Tc ranged from 0.06 to 0.33 and from 0.05 to 0.36 ng/g for tumbleweed and cheatgrass, respectively. Shoot concentration generally decreased with increasing time of harvest.
Date: January 1, 1977
Creator: Routson, R. C. & Cataldo, D. A.
Partner: UNT Libraries Government Documents Department

Evaluation of the radionuclide concentrations in soil and plants from the 1975 terrestrial survey of Bikini and Eneu Islands

Description: In June 1975 a radiological survey was conducted of the terrestrial environment of Bikini and Eneu islands (Bikini Atoll) to evaluate the potential radiation dose to the returning Bikini population. In this report, we present measurements of the radionuclide concentration in soil profiles and in dominant species of edible and nonedible, indicator plants. The use of these data to derive relationships to predict the plant uptake of radionuclides from soil is described. Approximately 620 soil and vegetation samples from Bikini and Eneu Islands were analyzed by Ge(Li) gamma spectrometry and by wet chemistry. The predominant radionuclides in these samples were /sup 60/Co, /sup 90/Sr, /sup 137/Cs, /sup 239,240/Pu, /sup 241/Pu, and /sup 241/Am.
Date: January 21, 1977
Creator: Colsher, C.S.; Robison, W.L. & Gudiksen, P.H.
Partner: UNT Libraries Government Documents Department

16. 3 eV neutron capture in /sup 107/Ag: nuclear structure of /sup 108/Ag. [Transitions, J correlations,. pi. ]

Description: The ..gamma.. rays from neutron capture in the 0- resonance of /sup 107/Ag at 16.3 eV were studied. Thirteen primary transitions populate spin 1 levels in /sup 108/Ag below an energy of 1.5 MeV. Transitions from low lying levels change in intensity by as much as a factor of 2 between thermal neutron capture (largely spin 1) and the 0- resonance, indicating a strong correlation of the population with level spin. 7 references.
Date: January 1, 1978
Creator: Orr, G. B.; Kane, W. R. & Smith, G. J.
Partner: UNT Libraries Government Documents Department

Absolute intensities of radiative deexcitation of /sup 46/Sc. [Widths, J, strength functions]

Description: The absolute radiative widths for E-1 and M-1 transitions in /sup 46/Sc were determined by neutron time-of-flight spectrometry. The level structure of /sup 46/Sc to 3 MeV has been studied by combining (n,..gamma..) data with previous charged particle data. As in /sup 36/Cl, scandium shows enhanced M-1&#x27;s. 5 references.
Date: January 1, 1978
Creator: Liou, H I & Chrien, R E
Partner: UNT Libraries Government Documents Department

Band structure in even-mass nuclei around A = 70. [Review]

Description: Studies of in-beam gamma rays from heavy-ion induced reactions were used to extensively explore the higher spin states of some of the even-mass nuclei around mass 70. This not only allowed observation of higher members of the ground-state band (up to spins of to 16), but also revealed a surprising variety of other bands. The various bands in such nuclei are reviewed, and some possible theoretical explanations are discussed. Five types of bands are considered. 32 references (JFP)
Date: January 1, 1978
Creator: Robinson, R.L. & Hamilton, J.H.
Partner: UNT Libraries Government Documents Department

Capture of 2 and 24 keV neutrons by the zirconium isotopes. [Cascade energies, J,. pi. ]

Description: The Zr isotopes were studied with the capture of 2- and 24-keV neutrons from the Brookhaven High Flux Reactor tailored beam facility. The binding energies of /sup 91/, /sup 92/ /sup 94/Zr were measured. The intensities of the primary ..gamma..-ray intensities for /sup 91/ /sup 92/ /sup 94/Zr are given and compared with previous experimental evidence. 9 references.
Date: January 1, 1978
Creator: Kenny, M J; Stelts, M L & Chrien, R E
Partner: UNT Libraries Government Documents Department

Collective motions and band structures in A = 60 to 80, even--even nuclei. [Review]

Description: Evidence for and the theoretical understanding of the richness of the collective band structures as illustrated by at least seven bands seen in levels of /sup 68/Ge, /sup 74/Se are reviewed. The experimental data on even-even nuclei in the A = 60 to 80 region have now revealed a wide variety of collective bands with different structures. The even parity yrast cascades alone are seen to involve multiple collective structures. In addition to the ground-state bands, strong evidence is presented for both neutron and proton rotation-aligned bands built on the same orbital, (g/sub 9///sub 2/)/sup 2/, in one nucleus. Several other nuclei also show the crossing of RAL bands around the 8/sup +/ level in this region. Evidence continues to be strong experimentally and supported theoretically that there is some type of shape transition and shape coexistence occurring now both in the Ge and Se isotopes around N = 40. Negative parity bands with odd and even spins with very collective nature are seen in several nuclei to high spin. These bands seem best understood in the RAL model. Very collective bands with ..delta..I = 1, extending from 2/sup +/ to 9/sup +/ are seen with no rotation-alignment. The purity of these bands and their persistence to such high spin establish them as an independent collective mode which is best described as a gamma-type vibration band in a deformed nucleus. In addition to all of the above bands, new bands are seen in /sup 76/Kr and /sup 74/Se. The nature of these bands is not presently known. 56 references. (JFP)
Date: January 1, 1978
Creator: Hamilton, J.H.; Robinson, R.L. & Ramayya, A.V.
Partner: UNT Libraries Government Documents Department

Comparative biokinetics of radiogallium and radioindium in mice

Description: The biokinetics of radiogallium and radioindium in normal mice are compared using the compartmental modelling analysis. The rate constants obtained provide useful information in understanding the physiological and biochemical kinetics of radionuclides in the intact object. A comparison of the compartmental models for gallium and indium reveals the similarities and differences between the biokinetics of the two radionuclides. Furthermore, the results provide valuable information and guidance for human studies and clinical use.
Date: January 1, 1978
Creator: Tsui, B.M.W. & Lathrop, K.A.
Partner: UNT Libraries Government Documents Department

Crystal field and magnetic properties of Dy(OH)/sub 3/, Ho(OH)/sub 3/ and Er(OH)/sub 3/

Description: The electric quadrupole and magnetic hyperfine interactions measured from the /sup 161/Dy Moessbauer resonance in crystalline Dy(OH)/sub 3/ and from the /sup 166/Er resonance in crystalline Ho(OH)/sub 3/ and Er(OH)/sub 3/ are interpreted using the crystal field and molecular exchange field model. The crystal field parameters established from previous optical spectroscopy results account well for these hyperfine parameters. The crystal-field and magnetic properties of these ferromagnetic insulators are described well within the model.
Date: January 1, 1978
Creator: Friedt, J.M.; Shenoy, G.K. & Dunlap, B.D.
Partner: UNT Libraries Government Documents Department