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in subjects: "Transplutonium Elements"

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Plutonium and americium processing chemistry and technology

Plutonium processing in the USA originated at Hanford and Los Alamos as part of the Manhattan Project in 1943. Hanford separated plutonium from irradiated reactor fuel, whereas Los Alamos purified the plutonium, as well as recovered plutonium from residues and scrap. In the early 1950's, similar processing facilities were constructed at Savannah River and Rocky Flats. The PUREX process (tri-n-butyl phosphate extraction) is used at Hanford and Savannah River plants to separate plutonium from irr… more

Date: January 1, 1984

Creator: Navratil, J.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Electronic structure of neutral and singly ionized curium

Extensive observations and analyses of the emission spectra of neutral and singly ionized curium, Cm I and Cm II, have resulted in the determination of 785 Cm I and 598 Cm II energy levels. These levels then combine to classify 9145 of the more than 14,250 lines of /sup 244/Cm observed between 240 and 2650 nm. Most of the levels have Lande g-values from Zeeman effect data and isotope shifts trom measurements of spectra from sources with various enrichments of /sup 244/Cm, /sup 245/Cm, /sup 246/… more

Date: February 1, 1985

Creator: Worden, E.F.; Conway, J.G. & Blaise, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Secondary Beams and the Synthesis of Exotic Nuclei

With the advent of modern fast cycling synchrotrons capable of delivering high intensity heavy ion beams up to uranium, the production of secondary radioactive ion beams (RIBs) with sufficient intensity has become feasible. The basic production mechanism is the fragmentation of near relativistic heavy ion beams on light targets. The physical facts underlying the efficient conversion of stable beams into RIBs are: (1) at beam energies of several 100 MeV/A thick conversion targets (1 to 10 g/cm/s… more

Date: September 1985

Creator: Nitschke, J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cleanex process: a versatile solvent extraction process for recovery and purification of lanthanides, americium, and curium

At a concentration of 1 M in straight-chain hydrocarbon diluent, HDEHP will extract americium, curium, and other trivalent actinide and lanthanide elements from dilute acid or salt solutions. The solute is back-extracted with more concentrated acid, either nitric or hydrochloric. The process has been used in the continuous, countercurrent mode, but its greatest advantage arises in batch extractions where the excess acid can be titrated with NaOH to produce a final acidity of about 0.03 M. Under… more

Date: January 1, 1979

Creator: Bigelow, J E; Collins, E D & King, L J

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Calculated masses and half-lives for nuclei in the region 100 less than or equal to Z less than or equal to 110

We have calculated nuclear masses and the corresponding ..cap alpha..-decay energies O/sub ..cap alpha../ and ..cap alpha.. half-lives T/sub ..cap alpha../ by use of the folded-Yukawa macroscopic-microscopic model, for nuclei at the end of the peninsula of known elements. We have also calculated, by use of the modified oscillator model, fission half-lives for even-even nuclei with Z between 100 and 110. The results agree well with data in this region, but an interpretation of the experimental d… more

Date: January 1, 1984

Creator: Leander, G. A.; Moeller, P.; Nix, J. R. & Howard, W. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Chemistry Research and Development. Progress Report, July 1977--April 1978

The following studies are reported on: calorimetry and thermodynamics of nuclear materials; actinide recovery and purification; optimization of the cation exchange process for recovering americium and plutonium from molten salt extraction residues; decontamination of soil; secondary actinide recovery; evaluation of tributyl phosphate-impregnated sorbent for plutonium-uranium separations; comparison of cation exchange recovery of actinides from the NaCl--KCl--MgCl/sub 2/ and CaCl/sub 2/--KCl--Mg… more

Date: November 8, 1978

Creator: Miner, F. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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In-line measurement of plutonium and americium in mixed solutions

A solution assay instrument (SAI) has been developed at the Los Alamos National Laboratory and installed in the plutonium purification and americium recovery process area in the Los Alamos Plutonium Processing Facility. The instrument is designed for accurate, timely, and simultaneous nondestructive analysis of plutonium and americium in process solutions that have a wide range of concentrations and Am/Pu ratios. For a 25-mL sample, the assay precision is < 1%, both for plutonium and for americ… more

Date: January 1, 1981

Creator: Li, T.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recoil spectrometer for the detection of single atoms

A much improved version of our gas-filled spectrometer for heavy-ion-induced fusion reactions is described. This instrument (SASSY II) is of the type D-Q-D wherein the dipoles are made with strong vertically-focussing gradients. The problems associated with experiments with cross sections in the picobarn range are discussed. In such experiments, it is necessary to identify single atoms with a high degree of confidence.

Date: April 1, 1987

Creator: Ghiorso, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Research in radiobiology. Annual report of work in progress in the internal irradiation program. [Lead]

Separate abstracts were prepared on 28 sections of this report that discusses the distribution and toxicity of injected isotopes of transuranium and other selected elements in dogs.

Date: March 31, 1978

Creator: Jee, W.S.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Recent studies of nuclear and chemical properties of elements 103, 104 and 105

Information obtained since 1983 on the nuclear and chemical properties of element 103, the last on the actinide series, and elements 104 and 105, at the beginning of the transactinide series, is reviewed. Their chemical properties are compared with their lanthanide and lighter group 4 and 5 homologs and evidence for possible relativistic effects is discussed. The current knowledge of the nuclear properties of these elements and how these affect of the study of chemical properties is discussed. … more

Date: August 1, 1990

Creator: Hoffman, D.C. (California Univ., Berkeley, CA (USA). Dept. of Chemistry Lawrence Berkeley Lab., CA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Nuclide migration in fractured or porous rock

In the ARDISC model, adsorption and desorption are treated independently. This paper describes an experimental study of the application of the ARDISC model to laboratory studies of nuclide migration in geologic media. Americium and strontium were used in the experiments. Results show that the migration can be treated in at least a semiquantitative fashion, that the ARDISC model is a useful aid, although it is limited to first-order sorption kinetics, and that kinetic parameters may be as import… more

Date: January 1, 1978

Creator: Rickert, P.G.; Strickert, R.G. & Seitz, M.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Nuclear reactions and synthesis of new transuranium species

In this short review, I shall describe the special aspects of heavy ion nuclear reaction mechanisms operative in the transuranium region, the role of new techniques, possible nuclear reactions for the production of additional transuranium elements and nuclear species and the importance of work in this region for the development of nuclear models and theoretical concepts. This discussion should make it clear that a continuing supply of leements and isotopes, some fo them relatively short-lived, … more

Date: January 1, 1983

Creator: Seaborg, G. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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X-ray powder diffraction of einsteinium compounds

X-ray powder diffraction (XRPD) analysis has proven to be extremely valuable in the study of the transplutonium elements. The high specific activity and the thermal energy associated with the radioactive decay of einsteinium isotopes make XRPD analysis of einsteinium samples very difficult. The major problems are destruction of the samples crystallinity and alteration of their chemical composition. Blackening of the X-ray film also compromises the analyses. By applying certain guidelines given … more

Date: January 1, 1978

Creator: Haire, R.G. & Peterson, J.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Predictive calculations of volatilities of metals and oxides in steam-containing environments

Predictive methods are developed for estimating the bond energies and free energy functions of volatile species having the general formula MO/sub x/ (OH)/sub y/, in order to shed some light on the mechanisms and extent of steam accelerated volatilization processes. A specific example of applying the data is illustrated for the case of a proposed underground radioactive waste disposal process, where oxides of radionuclides are allowed to equilibrate with 100 atm steam and 10/sup -2/ atm oxygen a… more

Date: August 10, 1981

Creator: Krikorian, Oscar H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Waste management of actinide contaminated soil. [Rocky Flats]

Waste management processes have been developed to reduce the volume of Rocky Flats soil contaminated with plutonium and americium and to prepare the contaminated fraction for terminal storage. The primary process consists of wet-screening. The secondary process uses attrition scrubbing and wet screening with additives. The tertiary process involves volume reduction of the contaminated fraction by calcination, or fixation by conversion to glass. The results of laboratory scale testing of the pro… more

Date: January 1, 1978

Creator: Navratil, J.D.; Thompson, G.H. & Kochen, R.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effect of radiolysis on leachability of plutonium and americium from 76-101 glass. [Glass containing 2 mole % plutonium]

One aspect of the leachability of actinide-bearing glass which has not been adequately addressed is the effect of radiolysis of the system (glass-water) on the amount of actinides liberated from the glass. In the present study, we have investigated the leaching of plutonium and americium from 76-101 glass samples (containing 2 mole % plutonium) in the presence of a one megaRad/hour gamma-radiation field. The presence of the radiation field was found to increase the leaching rate of both plutoni… more

Date: January 1, 1982

Creator: Nash, K.L.; Fried, S.; Friedman, A.M.; Susak, N.; Rickert, P.; Sullivan, J.C. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Exotic nuclear structures and decays: new nuclear collective phenomena

Studies of the properties of exotic nuclei have revealed a surprising richness and diversity in their shapes, structures, and decay modes far exceeding our understandings and expectations of even a decay ago. From studies of far-off-stability exotic nuclei have come evidence for the coexistence of different nuclear shapes in the same nucleus, new regions of unusually large deformation, new ground-state phase transitions from one shape to another, new magic numbers but now for deformed shapes, a… more

Date: January 1, 1986

Creator: Hamilton, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Comparison between CMPO and DHDECMP for alpha decontamination of radioactive liquid waste

Ion exchange is the major method used at Los Alamos to recover and purify plutonium from a variety of different contaminants. During this process, a high-acid (5-7M), low-activity stream is produced that presently is concentrated by evaporation, then cemented for long-term disposal. Our goal is to remove and concentrate the radioactive elements so that the remainder can be treated as low-level'' or regular industrial waste. Solvent extraction with neutral bifunctional extractants, such as DHDEC… more

Date: January 1, 1990

Creator: Muscatello, A. C.; Yarbro, S .L. & Marsh, S. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status of Sandia backfill-getter development studies

In this paper, specific functions desired of the backfill as well as various recent experimental studies, results, and current plans for further studies, and modeling of the backfill's effectiveness for delaying radionuclide release are presented. Experimental studies and results are as follows: smectite swelling clay, bentonite, has been selected as a major component in the backfill because of its favorable properties in contact with salt and brine solution; sorptive properties for Pu and… more

Date: January 1, 1980

Creator: Molecke, M.A. & Nowak, E.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High-temperature leaching of an actinide-bearing, simulated high-level waste glass

The chemical durability of a simulated high-level waste glass when exposed to high-temperature geologic solutions was investigated. In this study, simulated high-level waste glass-beads (76 to 68 glass)l doped with technetium, uranium, neptunium, plutonium, curium and americium were leached in deionized water, Waste Isolation Pilot Plant salt brine B, and 0.03M sodium bicarbonate solution at 150 and 250/sup 0/C for 2, 4, 8, 16, and 32 days. The resulting solutions were analyzed for several nonr… more

Date: March 1, 1983

Creator: Westsik, J. H. Jr.; Harvey, C. O. & Kuhn, W. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CPD`s potential for processing the higher transuranics

Hanford`s potential has been evaluated for producing higher transuranic isotopes, particularly curium-242 and curium-244. This document outlines the concepts visualized, and estimates the potential impact on CPD`s development, construction, and production programs. The irradiation program would proceed in 3 steps: production of fuel-grade plutonium, its burning to higher isotopes and alloying with Al for use in one reactor, and the separated americium irradiated to form curium-242. Disposition … more

Date: March 14, 1963

Creator: Tomlinson, R. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Partitioning of actinide elements from high-level waste using laser photochemical methods

The feasibility of photochemically fractionating the actinides in nuclear waste processing has been evaluated on a preliminary basis. The data indicate that there are potentially useful photo-redox reactions. However, there is a serious lack of data on photochemical parameters for the solutions conditions which exist in nuclear waste processing. The problem areas relevant to photochemical processing are identified. The experimental areas which must be investigated in order to further evaluate t… more

Date: May 1, 1976

Creator: Gangwer, T

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pacific Northwest Laboratory quarterly report to ERDA Nuclear Research and Applications Division, January--March 1976. [Use of /sup 90/SrF/sub 2/ and /sup 137/CsCl WESF capsules as heat sources]

Progress in the strontium heat source and beneficial isotopes utilization programs is discussed. The couples required for the long-term tests compatibility were fabricated and the tests are under way. The 1000-hr tests were completed, and examination of the test couples has been started. Compatibility testing of two full-scale WESF /sup 90/SrF/sub 2/ capsules at 800/sup 0/C has started. Additional short-term compatibility testing of 25 potential containment materials are also under way. The 500… more

Date: April 1, 1976

Creator: Fullam, H. T. & Harmon, K. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Review of actinide-sediment reactions with an annotated bibliography

The annotated bibliography is divided into sections on chemistry and geochemistry, migration and accumulation, cultural distributions, natural distributions, and bibliographies and annual reviews. (LK)

Date: February 10, 1976

Creator: Ames, L. L.; Rai, D. & Serne, R. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department