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Some Chemical Properties of Curium

Description: Report discussing details of curium's chemical properties, including gamma radiation, solubility, and absorption. A procedure for separating curium from americium and the preparation of terbium tetrafluoride, which lead to its discovery, is also included.
Date: April 12, 1954
Creator: Feay, Darrell Charles
Partner: UNT Libraries Government Documents Department

The Isolation and Properties of Curium

Description: From introduction: "The discovery of element number 96, curium, was realized by the preparation and identification of the isotope Cm-242 by G. T. Seaborg, R. A. James and A. Ghiorso by cyclotron bombardment of Pu-239 with helium ions."
Date: July 28, 1948
Creator: Werner, Louis Bernard
Partner: UNT Libraries Government Documents Department

Heat and Free Energy of the Reaction AmCl₃s + H₂O(g) = AmOCl(s) + 2HCl(g)

Description: In a previous paper a method of measuring the equilibrium constants at various temperatures for the titular reaction has been described. This report applies the method to an investigation of the corresponding reaction of americium, representing a part of a systematic program of investigation of the thermodynamic properties of analogous reactions of lanthanide and actinide elements.
Date: November 10, 1952
Creator: Koch, C. W. & Cunningham, Burris Bell, {}
Partner: UNT Libraries Government Documents Department

Preparation, Identification, and Crystal Structure of a Pentavalent Americium Compound, KAmO₂F₂

Description: From abstract: "A compound that is shown to be KAmO₂F₂ is prepared by the addition of a saturated solution of KF to an acid solution of pentavalent americium." The report further discusses the crystal structure, lattice parameters, number of molecules per unit cell, space group, and atomic positions for the compound.
Date: 1953
Creator: Asprey, L. B.; Ellinger, F. H. & Zachariasen, William H.
Partner: UNT Libraries Government Documents Department

Heats of Formation of Some Aqueous Ions of Americium

Description: Abstract: "The heats of formation of Pr-(+3) (aq.) and La-(+3) (aq.) have been measured in 1.5M HCl at 25 C. to be -165.9 +/- 0.9 kcal/mol and -167.0 +/- 0.7 kcal/mol, respectively. The heat of formation of Am-(+3) (aq.) under the same conditions was found to be -161.3 +/- 1.4 kcal/mol. The latter value made it possible to calculate the heat of formation of Am-(+4) (aq.) as -112.2 kcal/mol. It was impossible at this time to determine the heats of formation of AmO2+ (aq.) and AmO2++ (aq.)."
Date: 1950
Creator: Lohr, Harold Russell
Partner: UNT Libraries Government Documents Department

The Half Life of Am²⁴³

Description: This report calculates the alpha half-life of americium-243 and reporting a measurement error.
Date: 1953
Creator: Diamond, H.; Fields, Paul R.; Mech, Joseph; Inghram, Mark Gordon, {} & Hess, David C.
Partner: UNT Libraries Government Documents Department

THE ISOTOPES OF AMERICIUM

Description: Three new americium activities (Am{sup 238}?, Am{sup 243}, and Am{sup 244?}, the latter two formed by n,{gamma} reactions) are described and some additional information is given on previously reported americium isotopes.
Date: April 11, 1950
Creator: Street, K.; Ghiroso, A. & Seaborg, G.T.
Partner: UNT Libraries Government Documents Department

Plutonium and Americium Geochemistry at Hanford: A Site Wide Review

Description: This report was produced to provide a systematic review of the state-of-knowledge of plutonium and americium geochemistry at the Hanford Site. The report integrates existing knowledge of the subsurface migration behavior of plutonium and americium at the Hanford Site with available information in the scientific literature regarding the geochemistry of plutonium and americium in systems that are environmentally relevant to the Hanford Site. As a part of the report, key research needs are identified and prioritized, with the ultimate goal of developing a science-based capability to quantitatively assess risk at sites contaminated with plutonium and americium at the Hanford Site and the impact of remediation technologies and closure strategies.
Date: August 23, 2012
Creator: Cantrell, Kirk J. & Felmy, Andrew R.
Partner: UNT Libraries Government Documents Department

Separation of americium from europium by solvent extraction from aqueous phosphonate media

Description: Complexes between Am{sup 3+} or Eu{sup 3+} and phosphonoacetic acid differ in relative stability in accord with the electrostatic model of cation binding. The smaller Eu{sup 3+} cation forms stronger complexes with PAA than the larger Am{sup 3+} cation. The observed metal complexes in the acid range from 0.005 M to 0.02 M (at I= 0.5 M) are Eu(HL){sup +}, Eu(H{sub 3}L){sub 2}{sup +}, Eu(HL){sub 2}{sup {minus}} and Am(H{sub 2}L){sup 2+}, Am(HL){sup +}, Am(H{sub 2}L){sub 2}{sup +}. When used as a holdback reagent, PAA slightly enhances the separation of Am/Eu when used with sulfonic acids or CMPO/nitrate, but reduces separation efficiency with HDEHP. In a CMPO/SCN{sup {minus}} extraction system which favors extraction of Am over Eu, addition of PAA increases the separation efficiency by a factor of 2-3 at 0.3 M PAA/0.5 M SCN{sup {minus}}. The calculated stability constants can be used to explain the separation factors, but do not always accurately predict metal distribution ratios in the CMPO systems, implying that there are details of this system which have not been fully elucidated.
Date: December 31, 1994
Creator: Ensor, D.D. & Nash, K.L.
Partner: UNT Libraries Government Documents Department

The Vapor Phase Hydrolysis of the Trichlorides of Lanthanum, Praseodymium, Samarium, and Americium

Description: The following report studies the reactions of vapor phase hydrolysis of the trichlorides of lanthanum, praseodymium, samarium, and americium with gas mixtures of HCl and H2O passing over the solid materials mounted on a cantilever-type quartz fiber microbalance. This report calculates the values of the heats and entropies of the reactions, as well as the heat formation of LaCl3, 1254.9 kcal mol-(-1) that was obtained by determining the heat of the solution of La metal in 1.5M HCl.
Date: 1943
Creator: Broido, Abraham
Partner: UNT Libraries Government Documents Department

The Radiolysis of AmVI Solutions

Description: The reduction of bismuthate-produced AmVI by 60Co gamma-rays was measured using post-irradiation UV/Vis spectroscopy. The reduction of AmVI by radiolysis was rapid, producing AmV as the sole product. Relatively low absorbed doses in the ~0.3 kGy range quantitatively reduced a solution of 2.5 x 10-4 M AmVI. The addition of bismuthate to samples during irradiation did not appear to protect AmVI from radiolytic reduction during these experiments. It was also shown here that AmV is very stable toward radiation. The quantitative reduction of the AmVI concentration here corresponds to 1.4 hours of exposure to a process solution, however the actual americium concentrations will be higher and the expected contact times short when using centrifugal contactors. Thus, the reduction rate found in these initial experiments may not be excessive.
Date: June 1, 2013
Creator: Mincher, Bruce J.
Partner: UNT Libraries Government Documents Department

In Vitro Dissolution Tests of Plutonium and Americium Containing Contamination Originating From ZPPR Fuel Plates

Description: Assessing the extent of internal dose is of concern whenever workers are exposed to airborne radionuclides or other contaminants. Internal dose determinations depend upon a reasonable estimate of the expected biological half-life of the contaminants in the respiratory tract. One issue with refractory elements is determining the dissolution rate of the element. Actinides such as plutonium (Pu) and Americium (Am) tend to be very refractory and can have biological half-lives of tens of years. In the event of an exposure, the dissolution rates of the radionuclides of interest needs to be assessed in order to assign the proper internal dose estimates. During the November 2011 incident at the Idaho National Laboratory (INL) involving a ZPPR fuel plate, air filters in a constant air monitor (CAM) and a giraffe filter apparatus captured airborne particulate matter. These filters were used in dissolution rate experiments to determine the apparent dissolution half-life of Pu and Am in simulated biological fluids. This report describes these experiments and the results. The dissolution rates were found to follow a three term exponential decay equation. Differences were noted depending upon the nature of the biological fluid simulant. Overall, greater than 95% of the Pu and 93% of the Am were in a very slow dissolving component with dissolution half-lives of over 10 years.
Date: September 1, 2012
Creator: Bauer, William F.; Schuetz, Brian K.; Huestis, Gary M.; Lints, Thomas B.; Harris, Brian K.; Ball, R. Duane et al.
Partner: UNT Libraries Government Documents Department

Development of Neutron Probes for Characterization of Hazardous Materials in the Sub-surface Medium

Description: Neutron probes are being developed at the Idaho National Engineering and Environmental Laboratory (INEEL) for the detection, identification and quantification of hazardous materials in the ground. Such materials include plutonium, uranium, americium, chlorine and fluorine. Both a Neutron Gamma (NG) probe and a Prompt Fission Neutron (PFN) probe are being developed. The NG probe is used primarily for nuclide identification and quantification measurements. The PFN is used mostly for the detection and measurement of fissile material, but also for the determination of thermal neutron macroscopic absorption cross sections of the various elements comprising the ground matrix. Calibration of these probes will be carried out at the INEEL using an indoor facility that has been designed for this activity.
Date: August 1, 2002
Creator: Keegan, Raymond Patrick; McGrath, Christopher Andrew & Lopez, Juan Carlos
Partner: UNT Libraries Government Documents Department

Preparation of Americium Dioxide by Thermal Decomposition of Americium Oxalate in Air

Description: One hundred and seventy five grams of americium in a hydrochloric acid solution varying from 1 to 7 N was converted to americium dioxide. Americium oxalate was precipitated from 0.1 N HCI with 100% excess oxalic acid and was converted to the dioxide by calcination at 800 ts C in air. The solubility losses in the oxalate precipitation filtrate averaged approximately 7 mg/liter of solution, with a total loss of 0.09%. (auth)
Date: December 20, 1960
Creator: Baybarz, R. D.
Partner: UNT Libraries Government Documents Department

Report on 241,242Am(n,x) surrogate cross section measurement

Description: The main goal of this measurement is to determine the {sup 242}Am(n,f) and {sup 241}Am(n,f) cross sections via the surrogate {sup 243}Am. Gamma-ray data was also collected for the purpose of measuring the (n,2n) cross-sections. The experiment was conducted using the STARS/LIBERACE experimental facility located at the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory the first week of February 2011. A description of the experiment and status of the data analysis follow.
Date: February 16, 2011
Creator: Burke, J. T.; Ressler, J. J.; Gostic, J.; Henderson, R. A.; Bernstein, L. A.; Escher, J. E. et al.
Partner: UNT Libraries Government Documents Department