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Project AN0115A Annual Report, 1976: Migration of Plutonium and Americium in the Lithosphere

Description: Annual report of Argonne National Laboratory project ANO115A. Abstract: Studies have been carried out on the migration of plutonium and americium in solutions flowing through porous and crushed rock and through fissures. The migration process can be described in terms of the surface absorption of these elements. In addition, chemical effects on the absorption have been observed. One of these effects is possibly due to the presence of a plutonium polymer that migrates at a more rapid rate than normal plutonium.
Date: 1976
Creator: Hines, J. J.; Friedman, M. A.; Fried, S.; Atcher, Robert Whitehill; Quarterman, L. A. & Volesky, A.
Partner: UNT Libraries Government Documents Department

Isotopic measurements of uranium and plutonium by resonance-ionization mass spectrometry

Description: Isotopic measurements of the elements uranium and plutonium have been carried out using laser-excited resonance ionization mass spectrometry (RIMS). This technique makes use of the high elemental selectivity inherent in the resonance-ionization process which results in complete removal of isobaric (same-mass) interferences. The requirements of the laser system and atomization source will be discussed with emphasis on maximizing the efficiency of temporal overlap, thus increasing the sensitivity of the technique. Results will be shown for resin-bead loaded samples containing a mixture of NBS standard reference materials of U and Pu at the nanogram level. Data will be presented which demonstrate the selectivity, accuracy, and precision of RIMS compared to the conventional thermal ionization technique.
Date: January 1, 1983
Creator: Donohue, D.L.; Young, J.P. & Smith, D.H.
Partner: UNT Libraries Government Documents Department

Analysis of U and Pu resin bead samples with a single stage mass spectrometer

Description: Resin bead sampling enables the shipment of nanogram U and Pu quantities for analysis. Application of this sampling technique to safeguards was investigated with a single-stage mass spectrometer. Standards gave results in good agreement with NBS certified values. External precisions of +-0.5% were obtained on isotopic ratios of approx. 0.01; precisions on quantitative measurements are +-1.0%. (DLC)
Date: January 1, 1979
Creator: Smith, D.H.; Walker, R.L.; Bertram, L.K. & Carter, J.A.
Partner: UNT Libraries Government Documents Department

Three-stage mass spectrometer for isotopic analysis of radionuclides in environmental samples

Description: A three-stage mass spectrometer was constructed for isotopic analysis of several radioactive as well as stable elements at environmental levels. The spectrometer is interfaced to a digital computer, which controls the operation of the spectrometer, accumulates data, reduces data, and prints a final result. The spectrometer has demonstrated the capability of measuring the isotopic composition of plutonium samples as small as 0.005 picogram and has an abundance sensitivity greater than 10/sup 8/.
Date: September 1, 1981
Creator: Halverson, J.E.
Partner: UNT Libraries Government Documents Department

Thorium resonance ionization mass spectrometry for geochronological and geochemical applications

Description: Resonance Ionization Mass Spectrometry (RIMS) is being developed to measure thorium isotopics from geological samples. These measurements, in conjunction with uranium measurements by thermal ionization, permit geochronological dating in the timescale of 10,000 to 350,000 years. 15 refs., 2 figs.
Date: January 1, 1990
Creator: Fearey, B.L.; Johnson, S.G.; Nogar, N.; Murrell, M.T. & Miller, C.M.
Partner: UNT Libraries Government Documents Department

US developments in technology for uranium enrichment

Description: The purpose of this paper is to review recent progress and the status of the work in the United States on that part of the fuel cycle concerned with uranium enrichment. The United States has one enrichment process, gaseous diffusion, which has been continuously operated in large-scale production for the past 37 years; another process, gas centrifugation, which is now in the construction phase; and three new processes, molecular laser isotope separation, atomic vapor laser isotope separation, plasma separation process, in which the US has also invested sizable research and development efforts over the last few years. The emphasis in this paper is on the technical aspects of the various processes, but the important economic factors which will define the technological mix which may be applied in the next two decades are also discussed.
Date: January 1, 1982
Creator: Wilcox, W.J. Jr. & McGill, R.M.
Partner: UNT Libraries Government Documents Department

Chemistry of berkelium: a review

Description: Element 97 was first produced in December 1949, by the bombardment of americium-241 with accelerated alpha particles. This new element was named berkelium (Bk) after Berkeley, California, the city of its discovery (Thompson, Ghiorso, and Seaborg, Phys. Rev. 77, 838 (1950); 80, 781 (1950)). In the 36 years since the discovery of Bk, a substantial amount of knowledge concerning the physicochemical properties of this relatively scarce transplutonium element has been acquired. All of the Bk isotopes of mass numbers 240 and 242 through 251 are presently known, but only berkelium-249 (..beta../sup -/ decay, 0.125 MeV, t/sub 1/2/ = 325 days) is available in sufficient quantities for bulk chemical studies. About 0.7 gram of this isotope has been isolated at the HFIR/TRU Complex in Oak Ridge, Tennessee in the last 18 years. Over the same time period, the scale of experimental work using berkelium-249 has increased from the tracer level to bulk studies at the microgram level to solution and solid state investigations with milligram quantities. Extended knowledge of the physicochemical behavior of berkelium is important in its own right, because Bk is the first member of the second half of the actinide series. In addition, such information should enable more accurate extrapolations to the predicted behavior of heavier elements for which experimental studies are severely limited by lack of material and/or by intense radioactivity.
Date: January 1, 1985
Creator: Hobart, D.E. & Peterson, J.R.
Partner: UNT Libraries Government Documents Department

The performance of actinide-containing SRL 165 type glass in unsaturated conditions

Description: As part of the effort by the Nevada Nuclear Waste Storage Investigations (NNWSI) Project to evaluate the volcanic tuff beds of Yucca Mountain, Nevada, as a repository for the permanent storage of high-level nuclear waste, the interaction of actinide-doped Savannah River Laboratory (SRL) 165 type glass with the unsaturated repository environment has been studied. The NNWSI Unsaturated Test method has been used, and the results from batch and continuous tests completed through 18 months demonstrate that several interactions are important for controlling both the reaction of the glass and the release of radionuclides. These interactions include (1) the reaction between the glass and moist air with interludes of liquid water contact, which results in the release of alkali metals from the glass; and (2) the reaction between standing water, glass, and presensitized 304 L type stainless steel which results in breakdown of the glass matrix and the release of radionuclides from the glass-metal assemblage. A comparison of the results of the Unsaturated Test with those of parametric experiments illustrates the importance of presensitized steel in enhancing the glass reaction, and demonstrates the applicability of the Unsaturated Test to those conditions anticipated to exist in the NNWSI repository horizon. 10 refs., 8 figs., 1 tab.
Date: December 31, 1987
Creator: Bates, J.K. & Gerding, T.J.
Partner: UNT Libraries Government Documents Department

2. 05 x 10/sup 9/ age of the Oklo uranium deposit

Description: U and Pb isotopic data on samples (10 to 100 gram) 2 to 10 m away from the borders of the Oklo reactor zones indicate a primary age of 2.05 x 10/sup 9/ years for the Oklo deposit and a secondary age of 0.375 x 10/sup 9/ years. All samples show effects of Pb loss; the average loss is 50 percent. Both the U--Pb and Pb isotopic data are consistent with a model of a primary 2.05 x 10/sup 9/ year age of the deposit, continuous volume diffusion of Pb from uraninite, and either continuous or recent loss of this Pb. In this case the 0.375 x 10/sup 9/ year age is an artifact without time significance. Using an average value of D/a/sup 2/ 3.5 x 10/sup -11/ a/sup -1/ (Cowan, this conference) this model explains the apparent 1.8 x 10/sup 9/ year Pb age observed by other workers. From the /sup 208/Pb//sup 206/Pb data the average U/Th value calculated for the Oklo deposit is approximately 100.
Date: January 1, 1977
Creator: Gancarz, A. J.
Partner: UNT Libraries Government Documents Department

Status of /sup 241/Am recovery and purification at Los Alamos Scientific Laboratory

Description: Americium recovery was initiated at Los Alamos Scientific Laboratory (LASL) in the late 1940's. The early procedures separated gram quantities of americium from large amounts of impurities including plutonium and the rare earths. Ion exchange procedures were developed for further purification. Until recently, no routine processing of americium has been done at LASL for several years. The increasing demand for americium in oil-well logging instruments and other uses led LASL to develop and install a process to recover larger quantities of americium. The LASL process was developed around the chemistry of americium that had been elucidated both at LASL and at other facilities. Presently, the americium feed is obtained as a by-product from a plutonium purification process at the new plutonium facility at LASL. This feed filtrate from a peroxide precipitation process is precipitated as a slurry of hydroxides, filtered, dissolved in nitric acid, and passed through an anion exchange column to remove any residual plutonium. The americium, contained in the effluent, is precipitated as the oxalate and calcined to the oxide. Americium is also available in other highly salted acidic process streams. These should lend themselves to solvent extraction. Developmental work has been promising, and a dibutyl butyl phosphate-kerosene extraction process is being brought on-line.
Date: January 1, 1980
Creator: Ramsey, H.D.; Clifton, D.G.; Hayter, S.W.; Penneman, R.A. & Christensen, E.L.
Partner: UNT Libraries Government Documents Department

Interpretation of subcriticality measurements with strong spatial effects

Description: A methodology has been developed to account for spatial effects in subcriticality measurements. Using experimental data, this new analysis methodology allows estimation of model contamination without previous knowledge about the system, neither in the form of neutronic or geometric factor calculations. 5 refs., 1 fig.
Date: January 1, 1987
Creator: March-Leuba, C.; March-Leuba, J. & Difilippo, F.C.
Partner: UNT Libraries Government Documents Department

Review of AVLIS technology for production-scale LIS systems and construction

Description: The use of lasers for uranium and/or plutonium isotope separation is expected to be the first application of lasers utilizing specific atomic processes for large-scale materials processing. Specific accomplishments toward the development of production-scale technology for LIS systems will be presented, along with the status of major construction projects. 24 figures.
Date: December 1, 1983
Creator: Davis, J.I. & Moses, E.I.
Partner: UNT Libraries Government Documents Department

Fission cross section ratios for sup 233,234,236 U relative to sup 235 U from 0. 5 to 400 MeV

Description: Neutron-induced fission cross section ratios from 0.5 to 400 MeV for samples of {sup 233, 234, 236}U relative to {sup 235}U have been measured at the WNR neutron Source at Los Alamos. The fission reaction rate was determined using a fast parallel plate ionization chamber at a 20-m flight path. Cross sections over most the energy range were also extracted using the neutron fluence determined with three different proton telescope arrangements. Those data provided the shape of the {sup 235}U(n,f) cross section relative to the hydrogen scattering cross section. That shape was then normalized to the very accurately known value for {sup 235}U(n,f) at 14.1 MeV to allow us to obtain cross section section values from the ratio data and our values for {sup 235}U(n,f). 6 refs., 1 fig.
Date: January 1, 1991
Creator: Lisowski, P.W.; Gavron, A.; Parker, W.E.; Balestrini, S.J. (Los Alamos National Lab., NM (USA)); Carlson, A.D.; Wasson, O.A. (National Inst. of Standards and Technology, Gaithersburg, MD (USA)) et al.
Partner: UNT Libraries Government Documents Department

Laboratory-scale shielded cell for /sup 252/Cf

Description: A shielded-cell facility for storing and handling remotely up to 2 milligram quantities of unencapsulated /sup 252/Cf has been built in a radiochemistry laboratory at the Test Reactor Area of the Idaho National Engineering Laboratory. Unique features of this facility are its compact bulk radiation shield of borated gypsum and transfer lines which permit the transport of fission product activity from /sup 252/Cf fission sources within the cell to a mass separator and to a fast radiochemistry system in nearby rooms.
Date: January 1, 1979
Creator: Anderl, R.A. & Cargo, C.H.
Partner: UNT Libraries Government Documents Department

AVLIS industrial access program

Description: This document deals with the procurements planned for the construction of an Atomic Vapor Laser Isotope Separation (AVLIS) production plant. Several large-scale AVLIS facilities have already been built and tested; a full-scale engineering demonstration facility is currently under construction. The experience gained from these projects provides the procurement basis for the production plant construction and operation. In this document, the status of the AVLIS process procurement is presented from two viewpoints. The AVLIS Production Plant Work Breakdown Structure is referenced at the level of the items to be procured. The availability of suppliers for the items at this level is discussed. In addition, the work that will result from the AVLIS enrichment plant project is broken down by general procurement categories (construction, mechanical equipment, etc.) and the current AVLIS suppliers are listed according to these categories. A large number of companies in all categories are currently providing AVLIS equipment for the Full-Scale Demonstration Facility in Livermore, California. These companies form an existing and expanding supplier network for the AVLIS program. Finally, this document examines the relationship between the AVLIS construction project/operational facility and established commercial suppliers. The goal is to utilize existing industrial capability to meet the needs of the project in a competitive procurement situation. As a result, costs and procurement risks are both reduced because the products provided come from within the AVLIS suppliers' experience base. At the same time, suppliers can benefit by the potential to participate in AVLIS technology spin-off markets. 35 figures.
Date: November 15, 1984
Partner: UNT Libraries Government Documents Department

Transient data acquisition techniques under EDS

Description: This paper is the first of a series which describes the Enrichment Diagnostic System (EDS) developed for the MARS project at Lawrence Livermore National Laboratory. Although EDS was developed for use on AVLIS, the functional requirements, overall design, and specific techniques are applicable to any experimental data acquisition system involving large quantities of transient data. In particular this paper will discuss the techniques and equipment used to do the data acquisition. Included are what types of hardware are used and how that hardware (CAMAC, digital oscilloscopes) is interfaced to the HP computers. In this discussion the author will address the problems encountered and the solutions used, as well as the performance of the instrument/computer interfaces. The second topic the author will discuss is how the acquired data is associated to graphics and analysis portions of EDS through efficient real time data bases. This discussion will include how the acquired data is folded into the overall structure of EDS providing the user immediate access to raw and analyzed data. By example you will see how easily a new diagnostic can be added to the EDS structure without modifying the other parts of the system. 8 figs.
Date: June 1, 1985
Creator: Telford, S.
Partner: UNT Libraries Government Documents Department

Characteristics of the samples in the FNG fission deposit collection

Description: Information concerning the samples in the Fast Neutron Generator (FNG) Group's fission deposit collection has been assembled. This includes the physical dimensions, isotopic analyses, half-lives, alpha emission rates specific activities and deposit weights. 10 refs., 9 figs., 5 tabs.
Date: December 1, 1990
Creator: Meadows, J.W.
Partner: UNT Libraries Government Documents Department

Isotopic safeguards techniques

Description: Information is presented to explain and illustrate the idea and uses of isotopic safeguards techniques. A generalized, simple approach is maintained to facilitate understanding of the techniques. Once understood, the application, demonstration, and implementation of isotopic safeguards techniques becomes much easier.
Date: June 1, 1978
Creator: Timmerman, C.L.
Partner: UNT Libraries Government Documents Department

Intercomparison of U-238 deposits employed for neutron fluence determination in neutron activation cross section measurements

Description: An intercomparison is made between a collection of five uranium deposits used for neutron fluence determination in neutron activation experiments at Argonne National Laboratory (ANL), Illinois, USA, and a single corresponding deposit from the Institut fuer Radiumforschung und Kernphysik (IRK), Vienna, Austria. The predominant uranium isotope in each of these deposits is U-238. Two methods were used in the study: low-solid-angle alpha counting and the measurement of fast-neutron fission yield ratios. This investigation produced the following calibration values for the IRK deposit: (160.6 {plus minus} 1.7) micrograms from alpha counting and (163.3 {plus minus} 2.0) micrograms from fission ratio measurements. The latter value is a weighted average of twenty-four separate measurements. 13 refs., 2 figs., 4 tabs.
Date: January 1, 1989
Creator: Meadows, J.W.; Smith, D.L.; Winkler, G.; Vonach, H.; Wagner, M. (Argonne National Lab., IL (USA) & Kernphysik), Vienna Univ. (Austria). Inst. fuer Radiumforschung und
Partner: UNT Libraries Government Documents Department

Derivation of uranium residual radioactive material guidelines for the Ventron site

Description: Residual radioactive material guidelines for uranium were derived for the Ventron site in Beverly, Massachusetts. This site has been identified for remedial action under the Formerly Utilized Sites Remedial Action Program of the US Department of Energy (DOE). The derivations for the single radionuclides and the total uranium guidelines were based on the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the Ventron site should not exceed a dose of 100 mrem/yr following remedial action. The DOE residual radioactive material guideline computer code, RESRAD, which implements the methodology described in the DOE manual for implementing residual radioactive material guidelines, was used in this evaluation.
Date: March 1, 1992
Creator: Loureiro, C.; Yu, C. & Jones, L.
Partner: UNT Libraries Government Documents Department

MARS vessel safety analysis. LATA report No. 115

Description: A previous study was performed to assess the hazards associated with an accidental leakage of cooling water into the crucible of molten /sup 238/U for the MARS laser isotope separation experiment. Since that study found that the probability of such an explosion is extremely low during an accidental cooling system failure, a study was conducted to define a more realistic design basis accident (DBA) for the final MARS configuration. If the vapor-phase explosion is considered to be a significant threat, the design criteria for the vacuum vessel should be a working pressure of 67 psig or 101 psig momentary single pulse equivalent static pressure.
Date: August 1, 1979
Creator: Rigdon, L.D.; Donham, B.J. & Hughes, P.S.
Partner: UNT Libraries Government Documents Department

AVLIS production plant project schedule and milestones

Description: An AVLIS Production Plant Deployment Schedule for the engineering, procurement, and construction for both the Initial Increment of Production and the fully Activated Plant, has been developed by the project team consisting of Lawrence Livermore National Laboratory, Martin Marietta Energy Systems, Inc. with architect-engineer support from Bechtel National, Inc., Stone and Webster Engineering Corporation, and Westinghouse Corporation. The initial deployment phase consists of six separators modules and the three laser power amplifier modules consistent with the FY84 reference design with a name plate capacity of 5 million separative work units/yr followed by a full plant activation to approximately 13 million separative work units/yr. The AVLIS Production Plant project team's strategy for deployment schedule analysis focused on three schedule options: engineering limited schedule; authorization limited schedule; and funding limited project schedule. The three deployment schedule options developed by AVLIS project team have been classified in ranges such as an optimistic, rapid/moderate, or moderate/pessimistic based on the probability of meeting the individual schedule option's major milestones or program objectives of enriching uranium by the AVLIS process in an effective cost and schedule manner. 47 figures, 7 tables.
Date: November 15, 1984
Partner: UNT Libraries Government Documents Department