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in subjects: "Rare Earth Isotopes"

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Radionuclides in plankton from the South Pacific Basin

We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10/sup 4/. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northw… more

Date: March 23, 1984

Creator: Marsh, K.V. & Buddemeier, R.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Selective population of high-j states via heavy-ion-induced transfer reactions

One of the early hopes of heavy-ion-induced transfer reactions was to populate states not seen easily or at all by other means. To date, however, I believe it is fair to say that spectroscopic studies of previously unknown states have had, at best, limited success. Despite the early demonstration of selectivity with cluster transfer to high-lying states in light nuclei, the study of heavy-ion-induced transfer reactions has emphasized the reaction mechanism. The value of using two of these react… more

Date: January 1, 1982

Creator: Bond, P.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Long-lived heavy mass elements half-lives (A > 125)

Reported values of half-lives of intermediate mass and heavy elements are evaluated. The evaluation analysis estimates the systematic error the resulting standard deviation. Recommended values are then presented for /sup 128/Te, /sup 130/Te, /sup 129/I, /sup 138/La, /sup 144/Nd, /sup 145/Nd, /sup 146,147,148/Sm, /sup 152/Gd, /sup 154/Dy, /sup 176/Lu, /sup 174/Hf, /sup 180/Ta, /sup 187/Re, /sup 186/Os, /sup 190/Pt, /sup 204,205/Pb, and /sup 230,232/Th. 103 refs., 21 tabs. (WRF)

Date: January 1, 1985

Creator: Holden, Norman E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Isotopically selective, Doppler-free, saturation spectroscopy of lutetium isotopes via resonance ionization mass spectrometry

A new technique utilizing RIMS to obtain very high resolution atomic spectra with isotopic selectivity has been demonstrated. This technique allows the precise determination of HF splitting constants, limited only by the transition's natural linewidth. In addition, it is also feasible with this technique to accurately determine atomic isotope shifts. The exact determination of HF component line positions provides data for isotopically selective ionization which, in turn, will increase RIMS' dyn… more

Date: January 1, 1988

Creator: Fearey, B. L.; Parent, D. C.; Keller, R. A. & Miller, C. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Table of radioactive elements

As has been the custom in the past, the Commission publishes a table of relative atomic masses and halflives of selected radionuclides. The information contained in this table will enable the user to calculate the atomic weight for radioactive materials with a variety of isotopic compositions. The atomic masses have been taken from the 1984 Atomic Mass Table. Some of the halflives have already been documented.

Date: January 1, 1985

Creator: Holden, Norman E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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IBA in deformed nuclei

The structure and characteristic properties and predictions of the IBA in deformed nuclei are reviewed, and compared with experiment, in particular for /sup 168/Er. Overall, excellent agreement, with a minimum of free parameters (in effect, two, neglecting scale factors on energy differences), was obtained. A particularly surprising, and unavoidable, prediction is that of strong ..beta.. ..-->.. ..gamma.. transitions, a feature characteristically absent in the geometrical model, but manifest em… more

Date: January 1, 1982

Creator: Casten, R. F. & Warner, D. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Population and decay of high-spin states in /sup 157-161/Yb: evolution of nuclear shapes as a function spin and neutron number

The population and decay of the entry states in /sup 157-161/Yb and /sup 155-158/Er from the reactions of 136- and 149-MeV /sup 20/Ne with /sup 144/Nd and /sup 146/Nd have been investigated with the Spin Spectrometer gated with a Ge detector. Statistical-model calculations reproduce the main features of the entry state populations. The entry lines, <E/sup */> as a function of multiplicity, M/sub ..gamma../ show changes in slope at high M/sub ..gamma../ which are due to changes in the decay mode… more

Date: January 1, 1982

Creator: Jääskeläinen, M.; Sarantites, D. G.; Dilmanian, F .A.; Woodward, R.; Puchta, H.; Beene, J. R. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High-fidelity in isotope ratio measurements for resonance ionization mass spectrometry

Calculations are performed to gauge the effect of the convolution of atomic spectral characteristics with laser sources upon isotope ratio measurements by Resonance Ionization Mass Spectrometry (RIMS). Comparison with experimental data is included. 7 refs., 3 figs.

Date: January 1, 1988

Creator: Miller, C. M.; Fearey, B. L.; Palmer, B. A. & Nogar, N. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent experiments at Brookhaven: level structure of N = 86 isotones /sup 156/Yb and /sup 150/Gd

States of the N = 86 isotones /sup 156/Yb and /sup 150/Gd have been studied by means of the /sup 144/Sm(/sup 16/O,4n)/sup 156/Yb, /sup 113/In(/sup 46/Ti,p2n)/sup 156/Yb, and /sup 124/Sn(/sup 30/Si,4n)/sup 150/Gd reactions. Levels have been established to spin 36 h-bar and over 12.5 MeV in excitation in /sup 150/Gd and to beyond spin 25 h-bar in /sup 156/Yb. The systematics of levels in the N = 86 isotones from /sup 150/Gd to /sup 156/Yb are described, and the near-spherical shell model descript… more

Date: January 1, 1980

Creator: Sunyar, A W

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thulium-170 heat source

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipe… more

Date: September 6, 1990

Creator: Walter, Carl E.; Van Konynenburg, Richard & VanSant, James H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction]

The emergence of clearly defined applications for (small or large) amounts of long-life and reliable power sources has given the design and production of betavoltaic systems a new life. Moreover, because of the availability of the plasma separation program, (PSP) at TRW, it is now possible to separate the most desirable radioisotopes for betacell power generating devices. A computer code, named BCELL, has been developed to model the betavoltaic concept by utilizing the available up-to-date sour… more

Date: November 13, 1987

Creator: Taherzadeh, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Influence of humic-acid complexing on the mobility of Americium in the soil aquatic environment

Diffusion data indicate the Am, Cm and Np migrate 1.2, 0.8, and 26 centimeters, respectively, in a thousand years. Thus, excluding mass transport by moving water or wind, actinide elements, such as Cm, Am, and Np that find their way to the soil-aquatic environment are relatively immobile. Measured diffusion coefficients, corrected for distribution between the aqueous and soil phases, tortuosity, negative absorption, and relative fluidity are in reasonable agreement with aqueous diffusion coeffi… more

Date: March 1, 1982

Creator: Sheppard, J.C.; Campbell, M.J. & Kittrick, J.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fast neutron capture cross sections of /sup 169/Tm, /sup 191/Ir, /sup 193/Ir, and /sup 175/Lu for 3 less than or equal to E/sub n/ less than or equal to 2000 keV

Fast neutron capture cross sections of /sup 169/Tm, /sup 191/Ir, /sup 193/Ir, and /sup 175/Lu, and the /sup 6/Li(n,..cap alpha..)/sup 3/H cross sections to which they are normalized are presented in tabular form for neutron energies between 3 and 2000 keV.

Date: November 1, 1977

Creator: Macklin, R.L.; Drake, D.M. & Malanify, J.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Nuclear data for Gd-153 production

A compilation of neutron activation cross section data is provided. Data on this gadolinuim is needed because of its use as the working ingredient in an advanced medical scanning machine that can detect loss of bone minerals such as calcium, a possible cause of the disease osteoporosis. 4 refs.

Date: January 1, 1986

Creator: Holden, Norman E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Moessbauer effect of europium metal under pressure

The pressure dependence of the magnetic hyperfine field and of the isomer shift of /sup 151/Eu in europium metal has been studied in a diamond anvil pressure cell at low temperatures. In the pressure range 0-12 GPa at 44/sup 0/K (T/sub N/ = 90/sup 0/K), the magnetic hyperfine field changes from -22 T to -8 T while the isomer shift increases from -7.3 to -3.8 mm s/sup -1/ relative to a SmF/sub 3/ source. The changes are interpreted as indicative of a pressure-driven intermediate valence state ca… more

Date: September 1, 1986

Creator: Taylor, R. D. & Farrell, J. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status report on LWR spent fuel IAEA leach tests

Spent light-water-reactor (LWR) fuel with an average burnup of 28,000 MWd/MTU was leach-tested at 25/sup 0/C using a modified version of the International Atomic Energy Agency procedure. Leach rates were determined from tests conducted in five different solutions: deionized water, sodium chloride (NaCl), sodium bicarbonate (NaHCO/sub 3/), calcium chloride (CaCl/sub 2/) and Waste Isolation Pilot Plant B brine solutions. Elemental leach rates are reported based on the release of /sup 90/Sr + /sup… more

Date: March 1, 1980

Creator: Katayama, Y.B.; Bradley, D.J. & Harvey, C.O.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High spin isomers in /sup 153/Er

Energy levels of /sup 153/Er were investigated with four NaI detectors in coincidence with a Ge(Li) detector. The existence of two long-lived high-spin isomers was confirmed, and their positions and decays were established. 1 figure. (RWR)

Date: January 1, 1980

Creator: Horn, D.; Young, G. R.; Lister, C. J. & Baktash, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Novel, convenient, and nonpersistent radiotracer for environmental and energy applications

A newly-available radioisotopic system, /sup 172/Hf-/sup 172/Lu, has excellent potential for tracer applications in which nuclear data acquisition must be accomplished in real time. The 6.7-day half-life of /sup 172/Lu is sufficient for a large fraction of tracer experiments, and should allow the direct incorporation of /sup 172/Lu into tests that have traditionally utilized much longer-lived radionuclides. Since /sup 172/Lu is the daughter component of a radioisotope generator, however, its ef… more

Date: March 12, 1984

Creator: Grant, P.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Gamma-spectrometry with Compton suppressed detectors arrays

Recent results of experiments performed with two different Compton-suppressed detectors arrays in Daresbury and Berkeley (/sup 163,164/Yb and /sup 154/Er, respectively), are presented together with a brief description of the national French array presently under construction in Strasbourg. 25 refs., 15 figs.

Date: January 1, 1985

Creator: Schueck, C.; Hannachi, F.; Chapman, R.; Lisle, J. C.; Mo, J. N.; Paul, E. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evolution of nuclear shapes at high spins

The dynamic electric quadrupole (E2) moments are a direct reflection of the collective aspects of the nuclear wave functions. For this, Doppler-shift lifetime measurements have been done utilizing primarily the recoil-distance technique. The nuclei with neutron number N approx. 90 possess many interesting properties. These nuclei have very shallow minima in their potential energy surfaces, and thus, are very susceptible to deformation driving influences. It is the evolution of nuclear shapes as… more

Date: January 1, 1985

Creator: Johnson, N.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Compound nucleus studies withy reverse kinematics

Reverse kinematics reactions are used to demonstrate the compound nucleus origin of intermediate mass particles at low energies and the extension of the same mechanism at higher energies. No evidence has appeared in our energy range for liquid-vapor equilibrium or cold fragmentation mechanisms. 11 refs., 12 figs.

Date: June 1, 1985

Creator: Moretto, Luciano G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High-Spin Structure of /sup 163/Lu

The ..pi..1/2/sup +/(411) ground band structure of /sup 163/Lu shows a large signature splitting with inversion above the backbend suggesting a shape change associated with the triaxiality degree of freedom. The ..pi..1/2/sup -/(541) band shows no backbending up to h bar ..omega.. = 0.4 MeV indicating a more deformed structure. 7 refs., 3 figs.

Date: January 1, 1985

Creator: Honkanen, K.; Griffin, H. C.; Sarantites, D. G.; Abenante, V.; Adler, L. A.; Baktash, C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Photon-activation therapy

Photon Activation Therapy (PAT) is a technique in which radiation dose to tumor is enhanced via introduction of stable /sup 127/I in the form of iodinated deoxyuridine (IdUrd). Stimulation of cytotoxic effects from IdUrd is accomplished by activation with external (or implanted) radiation sources. Thus, accumulations of this nucleoside in actively competing cellpools do not preclude therapy in so far as such tissues can be excluded from the radiation field. Calculations show that 5% replacement… more

Date: January 1, 1982

Creator: Fairchild, R.G. & Bond, V.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Technical background information for the environmental and safety report, Volume 4: White Oak Lake and Dam

This report has been prepared to provide background information on White Oak Lake for the Oak Ridge National Laboratory Environmental and Safety Report. The paper presents the history of White Oak Dam and Lake and describes the hydrological conditions of the White Oak Creek watershed. Past and present sediment and water data are included; pathway analyses are described in detail.

Date: March 1, 1982

Creator: Oakes, T. W.; Kelly, B. A.; Ohnesorge, W. F.; Eldridge, J. S.; Bird, J. C.; Shank, K. E. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department