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Table of radioactive elements

Description: 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.
Partner: UNT Libraries Government Documents Department
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New look at the atomic volumes of the. beta. -form of the transplutonium metals

Description: The atomic volumes of the beta-form of the first four transplutonium metals were evaluated using data for samples prepared by thermal and by pressure treatment. The volumes derived for curium, berkelium, and californium metals quenched from elevated temperatures were found to be consistently larger than those for ''pressure-quenched'' samples, whose volumes were in good agreement with values for the alpha-forms. The cubic lattice parameters from ''pressure-quenched'' samples also provided a mor… more
Date: January 1, 1986
Creator: Haire, R.G.; Benedict, U.; Peterson, J.R.; Dufour, C. & Dabos, S.
Partner: UNT Libraries Government Documents Department
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Personnel neutron dosimetry studies at the Lawrence Livermore National Laboratory

Description: A study was conducted to determine the effect of phantom size, shape and composition on the response of an albedo neutron dosimeter. The most important feature was the shape. The dose equivalent rate from a californium neutron source was determined. Ten different dose rates were determined which varied from 2.39 to 3.02 rem/h for the CF source used. (ACR)
Date: June 9, 1981
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
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Extraction studies of selected actinide ions from aqueous solutions with 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione and tri-n-octylphosphine oxide

Description: The first measurements of distribution coefficients (K{sub d}) for Cm(III), Bk(III), Cf(III), Es(III), and Fm(III) between aqueous perchlorate solutions and solutions of 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT) and the synergist tri-n-octylphosphine oxide (TOPO) in toluene are reported. Curium-243, berkelium-250, californium-249, einsteinium-254, and fermium-253 were used in these studies. The K{sub d} for {sup 241}Am was also measured and is in agreement with previou… more
Date: November 1, 1991
Creator: Hannink, N. J.; Hoffman, D. C. (Lawrence Berkeley Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Chemistry) & Smith, B. F. (Los Alamos National Lab., NM (United States))
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

Description: 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
Partner: UNT Libraries Government Documents Department
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Electronic structure and bonding in transuranics: comparison with lanthanides

Description: The physico-chemical properties of the actinide metals, alloys, and compounds show interesting parallels and contrasts with the rare earths, beyond uranium. At first there is a transition region where the unique bonding properties of the early actinides become less prominent, due to progressive f-electron localization. Nevertheless, in contrast to the rare earths, f-electron energies remain close to the Fermi level, resulting in complex behavior as a function of temperature, pressure and struct… more
Date: January 1, 1983
Creator: Ward, J.W.
Partner: UNT Libraries Government Documents Department
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Extraction studies of selected actinide ions from aqueous solutions with 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione and tri-n-octylphosphine oxide

Description: The first measurements of distribution coefficients (K{sub d}) for Cm(III), Bk(III), Cf(III), Es(III), and Fm(III) between aqueous perchlorate solutions and solutions of 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT) and the synergist tri-n-octylphosphine oxide (TOPO) in toluene are reported. Curium-243, berkelium-250, californium-249, einsteinium-254, and fermium-253 were used in these studies. The K{sub d} for {sup 241}Am was also measured and is in agreement with previou… more
Date: November 1, 1991
Creator: Hannink, N. J.; Hoffman, D. C. & Smith, B. F.
Partner: UNT Libraries Government Documents Department
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Radiological safety considerations in the design and operation of the ORNL Transuranium Research Laboratory (TRL)

Description: The Transuranium Research Laboratory (TRL) is the central facility at Oak Ridge National Laboratory (ORNL) for chemical and physical research involving transuranium elements. Transuranium Research Laboratory investigations are about equally divided between studies of inorganic and structural chemistry of the heavy elements and nuclear structure and properties of their isotopes. Elements studied include neptunium, plutonium, americium, curium, berkelium, californium, and einsteinium, each in mic… more
Date: January 1, 1976
Creator: Haynes, C. E.
Partner: UNT Libraries Government Documents Department
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Californium production at the transuranium processing plant. [Transuranium processing plant design, equipment, and facilities]

Description: The Transuranium Processing Plant (TRU) at ORNL, which is the production, storage, and distribution center for the ERDA heavy element research program, is described. About 0.5 percent of /sup 252/Cf is currently being produced. TRU is a hot-cell, chemical processing facility of advanced design. New concepts have been incorporated into the facility for absolute containment, remote operation, remote equipment installation, and remote maintenance. The facilities include a battery of nine heavily s… more
Date: January 1, 1976
Creator: King, L. J.
Partner: UNT Libraries Government Documents Department
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Studies of californium metal at high pressure by x-ray diffraction

Description: The behavior of the crystal structure of californium metal under various pressures up to 140 kbars has been studied by use of a diamond-anvil type of miniature x-ray diffraction camera. Ten-microgram samples were encapsulated in aluminum foil, which also served as an internal standard for pressure determination. The phase transitions in cerium metal were produced and identified as a test of the apparatus and technique. Californium metal samples in the low-density face-centered cubic form (a/sub… more
Date: January 1, 1977
Creator: Burns, J. H. & Peterson, J. R.
Partner: UNT Libraries Government Documents Department
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Sorption of curium, berkelium, californium, and einsteinium on cation exchange resin from nitric acid solutions

Description: Plots of the distribution coefficients of curium, berkelium, einsteinium, and californium (+3 ions) adsorbed on Dowex 50-X8 resin from nitric acid solutions are U-shaped, while plots of einsteinium (+4 ions) distribution coefficients are similar to an exponential decay curve. The +3 ions exhibit a minimum sorption at a nitric acid concentration of 6 or 7 molar. (LK)
Date: January 1, 1976
Creator: Chilton, J. M.
Partner: UNT Libraries Government Documents Department
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Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies

Description: The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This… more
Date: February 1, 2011
Creator: Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P. et al.
Partner: UNT Libraries Government Documents Department
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Benchmark Analysis of Subcritical Noise Measurements on a Nickel-Reflected Plutonium Metal Sphere

Description: Subcritical experiments using californium source-driven noise analysis (CSDNA) and Feynman variance-to-mean methods were performed with an alpha-phase plutonium sphere reflected by nickel shells, up to a maximum thickness of 7.62 cm. Both methods provide means of determining the subcritical multiplication of a system containing nuclear material. A benchmark analysis of the experiments was performed for inclusion in the 2010 edition of the International Handbook of Evaluated Criticality Safety B… more
Date: September 1, 2009
Creator: Bess, John D. & Hutchinson, Jesson
Partner: UNT Libraries Government Documents Department
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PROCEEDINGS OF THE SYMPOSIUM COMMEMORATING THE 25th ANNIVERSARY OF ELEMENTS 97 and 98 HELD ON JAN. 20, 1975

Description: This volume includes the talks given on January 20, 1975, at a symposium in Berkeley on the occasion of the celebration of the 25th anniversary of the discovery of berkelium and californium. Talks were given at this symposium by the four people involved in the discovery of these elements and by a number of people who have made significant contributions in the intervening years to the investigation of their nuclear and chemical properties. The papers are being published here, without editing, in… more
Date: July 1, 1976
Creator: Seaborg, Glenn T.; Street Jr., Kenneth; Thompson, Stanley G. & Ghiorso, Albert
Partner: UNT Libraries Government Documents Department
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AN INTEGRAL REACTOR PHYSICS EXPERIMENT TO INFER ACTINIDE CAPTURE CROSS-SECTIONS FROM THORIUM TO CALIFORNIUM WITH ACCELERATOR MASS SPECTROMETRY

Description: The principle of the proposed experiment is to irradiate very pure actinide samples in the Advanced Test Reactor (ATR) at INL and, after a given time, determine the amount of the different transmutation products. The determination of the nuclide densities before and after neutron irradiation will allow inference of effective neutron capture cross-sections. This approach has been used in the past and the novelty of this experiment is that the atom densities of the different transmutation product… more
Date: April 1, 2010
Creator: Youinou, G.; Salvatores, M.; Paul, M.; Pardo, R.; Palmiotti, G.; Kondev, F. et al.
Partner: UNT Libraries Government Documents Department
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FUEL CYCLE ISOTOPE EVOLUTION BY TRANSMUTATION DYNAMICS OVER MULTIPLE RECYCLES

Description: Because all actinides have the ability to fission appreciably in a fast neutron spectrum, these types of reactor systems are usually not associated with the buildup of higher mass actinides: curium, berkelium and californium. These higher actinides have high specific decay heat power, gamma and neutron source strengths, and are usually considered as a complication to the fuel manufacturing and transportation of fresh recycled transuranic fuel. This buildup issue has been studied widely for ther… more
Date: June 1, 2010
Creator: Bays, Samuel; Piet, Steven & Dumontier, Amaury
Partner: UNT Libraries Government Documents Department
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Solvent extraction separation of trivalent lanthanide and actinide ions using an aqueous aminomethanediphosphonic acid.

Description: The possibility of separating the trivalent lanthanides, represented by EU{sup 3+}, and actinides, represented by Cf{sup 3+}, using HDEHP in toluene and an aqueous phase containing N-piperidinomethane-1,1-diphosphotic acid, PMDPA, has been investigated. This modified aqueous phase offers potential advantages over the diethylenetriaminepentaacetic acid based TALSPEAK process because of the improved complexation properties of PMDPA in acidic solutions, and the ability to decompose PMDPA before di… more
Date: October 14, 1998
Creator: Jensen, M. P.
Partner: UNT Libraries Government Documents Department
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A survey of metallurgical research on several actinides

Description: A Los Alamos perspective on metallurgical research on neptunium, plutonium, americium, curium, and californium is presented. Alloying behaviors of these metals are discussed. Metal fabrication technologies, principally for plutonium, are emphasized.
Date: November 1, 1993
Creator: Olivas, J. D. & Schonfeld, F. W.
Partner: UNT Libraries Government Documents Department
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Production, Distribution, and Applications of Californium-252 Neutron Sources

Description: The radioisotope {sup 252}Cf is routinely encapsulated into compact, portable, intense neutron sources with a 2.6-year half-life. A source the size of a person's little finger can emit up to 10{sup 11} neutrons/s. Californium-252 is used commercially as a reliable, cost-effective neutron source for prompt gamma neutron activation analysis (PGNAA) of coal, cement, and minerals, as well as for detection and identification of explosives, laud mines, and unexploded military ordnance. Other uses are… more
Date: October 3, 1999
Creator: Balo, P. A.; Knauer, J. B. & Martin, R. C.
Partner: UNT Libraries Government Documents Department
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Rapid increase in prescission GDR {gamma}-ray emission with energy

Description: A rapid increase in the emission of prescission giant dipole resonance (GDR) {gamma}-rays with bombarding energy is observed in excited Th and Cf nuclei formed in the reactions {sup 16}O+{sup 20B}Pb and {sup 32}S+{sup nat}W,{sup 208}Pb. This increase begins around E{sub exc} = 40 MeV for the {sup 16}O+{sup 208}Pb reaction and E{sub exc} = 70 MeV for the {sup 32}S-induced reactions. The excess {gamma}-ray yield above these thresholds cannot be described within the standard statistical model. Sta… more
Date: December 31, 1995
Creator: Hofman, D.J.; Back, B.B. & Paul, P.
Partner: UNT Libraries Government Documents Department
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Calibration of a Modified Californium Shuffler

Description: A californium shuffler originally designed to assay hollow cylindrical pieces of UA1 has been modified to assay solid cylinders. Calibration standards were characterized via chemical analysis of the molten UA1 taken during casting of the standards. The melt samples yielded much more reliable characterization data than drill samples taken from standards after the standards had solidified. By normalizing one well-characterized calibration curve to several standards at different enrichments, a rel… more
Date: June 1, 1995
Creator: Sadowski, E.T.; Armstrong, F.; Oldham, R.; Ceo, R. & Williams, N.
Partner: UNT Libraries Government Documents Department
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