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Final Report on the Large Scale Demonstration for the Electrochemical Processing of Hanford and Savannah River Site High-Level Waste Simulants

Description: This report details the pilot plant studies of the electrochemical destruction of nitrate, nitrite, and organics from simulated alkaline low-level nuclear waste solutions.
Date: September 21, 1995
Creator: Hobbs, D.T.; Chai, D.; Hartsough, D. & Genders, D.
Partner: UNT Libraries Government Documents Department

Process for treating alkaline wastes for vitrification

Description: According to its major aspects and broadly stated, the present invention is a process for treating alkaline waste materials, including high level radioactive wastes, for vitrification. The process involves adjusting the pH of the wastes with nitric acid, adding formic acid (or a process stream containing formic acid) to reduce mercury compounds to elemental mercury and MnO{sub 2} to the Mn(II) ion, and mixing with class formers to produce a melter feed. The process minimizes production of hydrogen due to noble metal-catalyzed formic acid decomposition during, treatment, while producing a redox-balanced feed for effective melter operation and a quality glass product. An important feature of the present invention is the use of different acidifying and reducing, agents to treat the wastes. The nitric acid acidifies the wastes to improve yield stress and supplies acid for various reactions; then the formic acid reduces mercury compounds to elemental mercury and MnO{sub 2}) to the Mn(II) ion. When the pH of the waste is lower, reduction of mercury compounds and MnO{sub 2}) is faster and less formic acid is needed, and the production of hydrogen caused by catalytically-active noble metals is decreased.
Date: January 1, 1994
Creator: Hsu, Chia-lin W.
Partner: UNT Libraries Government Documents Department

Coupling an optical trap to a mass separator

Description: The efficient coupling of a magneto-optical trap to a mass separator is being developed to undertake high-precision electroweak interaction measurements in a series of radioisotopes. The use of ion implantation and subsequent heated-foil release is being pursued as a suitable way of introducing radioactive samples into the ultrahigh vacuum region of an optical trap without gas loading. This paper discusses the layout of the mass separator,the coupling to a magneto- optical trap, and the implantation and release scheme.
Date: December 31, 1996
Creator: Chamberlin, E. P.; Sandberg, V. D.; Tupa, D.; Vieira, D. J.; Zhao, X. X.; Guckert, R. et al.
Partner: UNT Libraries Government Documents Department

Geochemistry, age and strontium isotope composition of late tertiary and quaternary basalts and andesites in western Nevada and their relation to geothermal potential. Final report, October 1, 1982-December 31, 1983

Description: This research was undertaken to characterize the late Cenozoic volcanic rocks associated with active geothermal systems in west-central Nevada. Petrographic and microprobe, geochemical and isotopic analysis and age dating techniques were used to characterize these young volcanic rocks. These data were combined with the limited data previously reported in the literature on these same volcanic areas to interpret their petrogenesis. The overall characterization resulted from integrating the petrogenesis with a structural-tectonic model of the region. Potassium-argon isotopic ages ranging up to 14 million years were determined for eight localities within the Reno 1 x 2/sup 0/ study region. These ages are consistent with the morphology of the volcanic landforms, the active geothermal systems associated with them, and with other isotopic ages reported in the literature for these and similar rocks within the study region. Petrographic analysis of hand specimens and thin-sections indicated mineralogic assemblages of the respective rock types and specific mineral textures and phenocryst compositions and characteristics. These identifications were further substantiated by microprobe analysis of selected phenocrysts and groundmass phases. Classification of the respective rock types was also based on chemical composition and normative calculations using the program PETCAL. Basaltic andesites are identified and described for Steamboat Hills, Table Mountain, Silver Springs, Churchill Butte, Cleaver Peak, Desert Peak and Carson City sites.
Date: January 1, 1984
Creator: Fultz, L.A.; Bell, E.J. & Trexler, D.T.
Partner: UNT Libraries Government Documents Department

Atomic negative ions

Description: We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.
Date: December 31, 1991
Creator: Brage, T.
Partner: UNT Libraries Government Documents Department

E2 and M1 strengths and strong sub-shell closure effects in neutron-rich A@100 nuclei

Description: E2 strengths of several A {approximately} 100 nuclei were deduced from ps level-lifetime measurements at the fission-product separator TRISTAN. The exceptionally low B(E2) values for {sup 90,92,94,96}Sr reveal a close similarity between spherical Sr and Zr nuclei. For Sr and Y nuclei with N {ge} 60, B(M1) and B(E2) values indicate that the deformation saturates just at its onset. A dramatic change in the Sr collectivity occurs at N = 60, where the B(E2) strength abruptly increases by a factor of {approximately}15, suggesting a phase change'' in the collectivity. 12 refs., 1 fig., 1 tab.
Date: January 1, 1990
Creator: Wohn, F.K.; Hill, J.C. (Ames Lab., IA (USA)); Mach, H. (Uppsala Univ., Nykoeping (Sweden). Studsvik Neutron Research Lab. Kernforschungsanlage Juelich GmbH (Germany, F.R.). Inst. fuer Kernphysik Brookhaven National Lab., Upton, NY (USA)); Molnar, G. (Kernforschungsanlage Juelich GmbH (Germany, F.R.). Inst. fuer Kernphysik Magyar Tudomanyos Akademia, Budapest (Hungary). Izotopintezete) & Sistemich, K
Partner: UNT Libraries Government Documents Department

Shell effects on the E1 moments of Ra-Th nuclei

Description: Large systematic shell effects on intrinsic E1 moments are found, which should modulate any E1 moment induced by ..beta../sub 3/ deformation. The calculated shell effects can explain an emerging trend for E1 data in Ra-Th nuclei, if and only if the gross ..beta../sub 3/-induced polarization of finite nuclear matter goes in the same direction as the lightning rod effect. 16 references.
Date: January 1, 1984
Creator: Leander, G.A.
Partner: UNT Libraries Government Documents Department

Strontium-90 in the US diet, 1982

Description: Estimates of /sup 90/Sr intake via the total diet in New York City and San Francisco have been made since 1960 from quarterly food samplings and average consumption statistics. The dietary intake of /sup 90/Sr has decreased from the maximum levels attained during 1963-1964, but the decline has become more gradual in recent years due to the continuing small amounts of /sup 90/Sr deposition and the little-changing cumulative deposit of /sup 90/Sr in soil. The annual intake in 1982 averaged 5.4 pCi/day (0.20 Bq/day) in New York, and 2.6 pCi/day (0.096 Bq/day) in San Francisco, little changed from the previous year. Further gradual reductions in /sup 90/Sr intake are anticipated during 1983. 1 reference, 7 figures, 4 tables.
Date: July 1, 1984
Creator: Klusek, C.S.
Partner: UNT Libraries Government Documents Department

Development of the NBS /sup 10/Be//sup 9/Be isotopic standard reference material

Description: The National Bureau of Standards (NBS), in conjunction with the Oak Ridge National Laboratory (ORNL) and the Accelerator Mass Spectrometry (AMS) community, is in the process of developing a /sup 10/Be//sup 9/Be isotopic solution Standard Reference Material (SRM). The starting /sup 10/Be//sup 9/Be solution was provided by the ORNL after Secondary Ionization Mass Spectrometric characterization for isotopic concentration. The radioactivity purity of the ORNL Master solution was confirmed by gamma-ray spectrometry, then diluted at NBS with solutions made from zone-refined single-crystal beryllium metal and sub-boiling double-distilled hydrochloric acid. Four serial dilutions were necessary to achieve a final /sup 10/Be//sup 9/Be isotopic composition of approximately 3 x 10/sup -11/ (g/g). The accuracy of the dilutions was confirmed by liquid scintillation and AMS measurements. The isotopic composition of the ORNL Master solution was also confirmed at NBS by Resonant Ionization Mass Spectrometry. The isotopic composition of the final solution is being affirmed at the present time through international laboratory AMS measurements.
Date: April 1, 1987
Creator: Inn, K.G.W.; Raman, S.; Coursey, B.M.; Fassett, J.D. & Walker, R.L.
Partner: UNT Libraries Government Documents Department

Axial asymmetry in the IBA and an extensive new 0(6) region near A=130

Description: Although the IBA-1 contains no solutions corresponding to a rigid triaxial shape, it does contain an effective asymmetry arising from zero point motion in a ..gamma..-soft potential leading to a non-zero mean or rms ..gamma... In the consistent Q Formalism (CQF) of the IBA, most results of calculation depend only on one parameter chi. A relation will be established between chi and the effective asymmetry parameter ..gamma... The relation between the asymmetry occurring naturally in IBA-1 and the triaxiality arising from the introduction of cubic terms into the IBA Hamiltonian will be discussed. It will be shown that ..gamma..-band energy staggering is a particularly sensitive indicator of the degree of ..gamma.. rigidity. Finally, an extensive new region of 0(6) like Xe and Ba nuclei near A=130 will be discussed. Their remarkable similarity to Pt will be explored. Deviations from the strict 0(6) limit can be described in terms of the interplay of soft and rigid axial asymmetry and calculations will be presented that interpret the Xe, Ba and Pt isotopes in this way. 25 references.
Date: January 1, 1984
Creator: Casten, R.F.
Partner: UNT Libraries Government Documents Department

Beryllium-10: Half-life and AMS-standards

Description: Absolute AMS measurements of /sup 10/Be require reliable standards for calibration. Among the existing standards, rather large differences have been observed. These differences were found partially to be due to the different half-life values which were assumed. Also for comparison of AMS data with activity measurements, it is necessary to know the /sup 10/Be half-life as precisely as possible. Starting with 5 ml of the standardized ORNL-MASTER solution, a working solution with a well-defined /sup 10/Be content was prepared. Its specific activity was determined by liquid scintillation counting. This measurement yielded a new value of (1.52 +- 0.05) My for the /sup 10/Be half-life, which is in agreement with the previously reported values but is about three times more accurate. Two independent dilution series produced new AMS standards with /sup 10/Be//sup 9/Be ratios of the order of 10/sup -10/ and 10/sup -11/. These standards were measured at the ETH/SIN AMS facility with high accuracy and are compared with other available /sup 10/Be standards. 15 refs, 2 figs., 3 tabs.
Date: January 1, 1987
Creator: Hofmann, H.J.; Beer, J.; Bonani, G.; von Gunten, H.R.; Raman, S.; Suter, M. et al.
Partner: UNT Libraries Government Documents Department

Generation and mobility of radon in soil

Description: This study has confirmed large seasonal and daily variations of Rn in soil gas, developed models for the effects of temperature and moisture on air-water Rn partition, inhibited Rn diffusion from wet soil into sparse large air-filled pores and effects of diffusion into bedrock, demonstrated that organic matter is a major host for 226Ra in soils and that organic-bound Ra largely determines the proportion of 222Rn emanated to pore space, shown that in contrast 220Rn is emanated mainly from 224Ra in Fe-oxides, detected significant disequilibrium between 226Ra and 238U in organic matter and in some recent glacial soils, demonstrated by computer models that air convection driven by temperature differences is expected in moderately permeable soils on hillsides.
Date: January 1, 1993
Creator: Rose, A.W.; Jester, W.A. & Ciolkosz, E.J.
Partner: UNT Libraries Government Documents Department

Advances in the helium-jet coupled on-line mass separator RAMA. [Recoil Atom Mass Analyzer]

Description: General improvements to the on-line mass separator RAMA (Recoil Atom Mass Analyzer) have yielded a greater reliability and efficiency for some elements. A new utilitarian helium-jet chamber has been installed to facilitate quick target and degrader foil changes in addition to a new ion source holder. A higher efficiency hollow-cathode, cathode-extraction ion source, for lower melting point elements (< 1200/sup 0/C) has also been designed. Tests with the beta-delayed proton emitter /sup 37/Ca showed a factor of five increase in yield over the old hollow-cathode, anode-extraction source. A differentially-pumped-tape drive system compatible with both ..gamma..-..gamma.. and ..beta..-..gamma.. experiments has been incorporated into the general detection system. All major operating parameters will soon be monitored by a complete stand-alone microprocessor system which will eventually be upgraded to a closed-loop control system.
Date: January 1, 1980
Creator: Moltz, D M; Aysto, J; Cable, M D; Parry, R F; Haustein, P E; Wouters, J M et al.
Partner: UNT Libraries Government Documents Department

Quarterly report on the strontium heat source development program, Advanced Nuclear Systems and Projects Division for April-June 1980

Description: Oak Ridge National Laboratory completed metallographic examination of the metal specimens from the 30,000-h compatibility tests with /sup 90/SrF/sub 2/. Electron microprobe analysis of the specimens is now under way. Results show that chemical attack of the 30,000-h specimens was not much greater than that observed in the 6000- to 20,000-h tests. Work continues on qualification testing of the as-fabricated prototype outer capsules. As-fabricated Hastelloy S and Hastelloy C-4 outer capsules passed the hydrostatic pressure, percussion, thermal, and thermal-quench tests without difficulty.
Date: July 1, 1980
Creator: Fullam, H.T.
Partner: UNT Libraries Government Documents Department

Large scale isolation of /sup 82/Sr for generator production

Description: A new chemical separation process has been developed at Los Alamos for the isolation of /sup 82/Sr from irradiated molybdenum targets. Large (up to 500 gram) molybdenum metal targets are irradiated for approximately one month at LAMPF. Following irradiation, a no-carrier-added radiochemically pure strontium fraction is obtained from a chemical separation process is simpler to run and results in a purer product than the process used in the past. This new procedure has been used in the production of up to 28 Curies of /sup 82/Sr at end-of-bombardment. The product will be made available for commercial production of the /sup 82/Sr//sup 82/Rb greater system for medical use. 4 figures, 3 tables.
Date: January 1, 1983
Creator: Thomas, K.E. & Barnes, J.W.
Partner: UNT Libraries Government Documents Department

Hot dry rock energy extraction field test: 75 days of operation of a prototype reservoir at Fenton Hill, Segment 2 of Phase I

Description: Results from the first extensive field test of a man-made hot dry rock (HDR) geothermal reservoir in low permeability crystalline rock are presented. A reservoir with a small heat transfer area was utilized to study the characteristics of a prototype HDR system over a shortened lifetime. The resulting accelerated thermal drawdown was modeled to yield an effective area of 8000 m/sup 2/. In addition to the thermal effects, this test provided an opportunity to examine equipment operation, water permeation into the formation, geochemical interaction between the circulating fluid and the rock and flow characteristics including impedance and residence time distributions. Continuous monitoring for induced seismic effects showed that no activity to a Richter threshold of -1.0 was detected during the 75-day experiment.
Date: April 1, 1979
Creator: Tester, J.W. & Albright, J.N. (eds.)
Partner: UNT Libraries Government Documents Department

Pairing interaction effects in exciton level densities

Description: Recent progress in pairing corrections for exciton state-density formulas used in pre-compound nuclear reaction theories is reviewed. These correction factors are, strictly speaking, dependent on the nuclear excitation energy U and the exciton number n. A simple formula for (U,n)-dependent pairing corrections has been derived, based on the BCS pairing equations for constant single-particle spacing, for the exciton state-density formula for one kind of Fermion. It has been shown that the constant-pairing-energy correction used in standard state-density formulas, such U{sub 0} in Gilbert and Cameron, is a limiting case of the general (U,n)-dependent results. Spin cutoff factors with pairing effects were also obtained using the same theory and parameterized into an explicit (U,n)-dependent function, thereby defining a simple exciton level-density formula for applications in quantum mechanical precompound theories. Preliminary results from extending such simple pairing-interaction representations to level-density formulas for two kinds of Fermions are summarized. The results show that the ratios in the exciton level densities in the one-Fermion and two-Fermion approaches vary with both U and n, thus likely leading to differences in calculated compound to precompound ratios. However, the differences in the spin cutoff factors in the two cases are found to be rather small. 12 refs., 3 figs.
Date: January 1, 1989
Creator: Fu, C.Y.
Partner: UNT Libraries Government Documents Department

Sudden shape change from shperical to maximally deformed for A/approx equal/100 nuclei

Description: Among the unusual features of neutron-rich A/approx equal/100 nuclei is a sudden change of nuclear shape. The analysis of B(E2) and B(M1) values from recent level lifetime measurements indicates that Sr (and perhaps also Zr) nuclei obtain their largest deformations for the nuclei at the onset of deformation, which suggest a ''phase change'' from a spherical to a maximally deformed shape. 15 refs., 6 figs.
Date: January 1, 1989
Creator: Wohn, F.K.; Mach, H.; Moszynski, M.; Gill, R.L. & Casten, R.F.
Partner: UNT Libraries Government Documents Department

Calcium isotope separation by chemical exchange with polymer-bound crown compounds

Description: Chromatographic separation of calcium isotopes by chemical exchange with polymer-bound 18-crown-6 was investigated. The breakthrough technique of column chromatography was employed to determine the influence of solvent composition and ligand-tether structure on separation coefficients and heterogeneous calcium complex stability. The separation coefficient, {epsilon}, was found to be strongly dependent upon solvent composition. An {epsilon} of 0. 0025{plus minus}0.0002 (95% C.L.) for the {sup 44}Ca/{sup 40}Ca isotope pair was obtained with a 70/30 (by volume) methanol/chloroform solvent mixture at 20.0{degree}C. Differences in the structure of the tether binding the crown ring to the polymer had no influence on {epsilon} at that solvent composition. 8 refs., 5 figs., 1 tab.
Date: January 1, 1990
Creator: Jepson, B.E.
Partner: UNT Libraries Government Documents Department

A fragment separator at LBL for beta-NMR experiment

Description: The Beam 44 fragment separator was built at the Bevalac of LBL for NMR studies of beta emitting nuclei. {sup 37}K, {sup 39}Ca, and {sup 43}Ti fragments originating from {sup 40}Ca and {sup 46}Ti primary beams were separated by the separator for NMR studies on these nuclei. Nuclear spin polarization was created in {sup 39}Ca and {sup 43}Ti using the tilted foil technique (TFT), and the magnetic moment of {sup 43}Ti was deduced. Fragment polarization was measured for {sup 37}K and {sup 39}Ca emitted to finite deflection angles. The Beam 44 fragment separator in combination with a proper polarization technique, such as TFT or fragment polarization, has been very effective for such NMR studies.
Date: March 1, 1992
Creator: Matsuta, K.; Ozawa, A.; Nojiri, Y.; Minamisono, T.; Fukuda, M.; Kitagawa, A. et al.
Partner: UNT Libraries Government Documents Department

Shielding consideration for a deuteron activated liquid lithium system

Description: A parametric study was conducted to evaluate the potential shielding implication due to the /sup 7/Be plateout on the lithium piping in the FMIT facility. Various parameters such as plateout percentage, hot flush efficiency and /sup 7/Be trapping efficiency were varied to assess the overall shielding requirement relationship. The /sup 7/Be plateout was found to place severe limitations on the hands-on maintenance access. Hot flush and /sup 7/Be traps are effective ways of minimizing the /sup 7/Be plateout. To be effective in reducing local shielding requirements, the combined /sup 7/Be trapping and hot flush efficiency shall be greater than 95%.
Date: September 1, 1979
Creator: Huang, S.T.; Shapiro, A.M.; Lee, J.B. & Miller, W.C.
Partner: UNT Libraries Government Documents Department

Rapid estimation of /sup 226/Ra in soil for the Grand Junction RASA/UMTRA project

Description: The Radiological Survey Activities (RASA) Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL) is an Inclusion Survey Contractor (ISC) for the Uranium Mill Tailings Remedial Action Program (UMTRAP). The purpose of the ISC is to survey designated sites potentially contaminated with radioactive material originating from the 24 inactive uranium mill sites and make recommendations as to whether the site should be included in or excluded from further consideration by UMTRAP. An important aspect of the program is a prompt and inexpensive estimation of Radium-226 (/sup 226/Ra) concentration in soil samples. A large sodium iodide (NaI) well crystal coupled to a multichannel analyzer is used to count soil samples. Count data are currently analyzed with an algorithm that utilizes three regions of interest (ROI). A lack of agreement was observed when samples were also analyzed with lithium-drifted germanium (GeLi) spectrometers. The average estimate of /sup 226/Ra obtained using the current algorithm was 19% greater than the GeLi determination. Some possible reasons for these differences were examined. In 8.5% of the samples, the relative concentration of Cesium-137 (/sup 137/Cs) was highly correlated to the extent of error. Using alternative analysis techniques, the error for /sup 226/Ra estimations may be reduced by a factor of 2 for randomly selected samples and by a factor of 4 for samples containing high concentrations of /sup 137/Cs relative to the concentrations of /sup 226/Ra. 9 refs., 4 figs., 3 tabs.
Date: January 1, 1986
Creator: Kark, J.B.; Borak, T.B.; Kearney, P.D. & Rood, A.S.
Partner: UNT Libraries Government Documents Department

Deposition and control of /sup 7/Be in liquid lithium

Description: Preferential beryllium-7 deposition has been found in the higher temperature region of non-isothermal flowing lithium between 270/sup 0/C to 200/sup 0/C. Various methods for controlling /sup 7/Be distribution for application to the Fusion Materials Irradiation Test (FMIT) facility are examined. Flushing a loop with 425/sup 0/C lithium decreased /sup 7/Be activity on pipe walls by 60 to 80%. Yttrium has been found to be more effective than the other materials tested for removal of /sup 7/Be from lithium. Preliminary results on diffusion traps indicate effectiveness for /sup 7/Be removal also.
Date: January 1, 1980
Creator: Bechtold, R.A.
Partner: UNT Libraries Government Documents Department

Interlevel transfer mechanisms and their application to GRASERS

Description: Within the gamma-ray laser (GRASER) research community, much attention is being given to two-step schemes that store energy in a long-lived isomeric state and achieve lasing by transferring population to a short-lived state. Because the electron system exhibits large multipole moments and is in the near field of the nucleus, it can be used as an intermediate mechanism for transferring energy, angular momentum, and parity change. Two distinct electron-nucleus interaction mechanisms are discussed: (1) resonant electronic transitions and (2) collective outer-shell excitations. 9 refs.
Date: January 1, 1985
Creator: Solem, J.C.
Partner: UNT Libraries Government Documents Department