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Decontamination of large horizontal concrete surfaces outdoors

Description: A study is being conducted of the resources and planning that would be required to clean up an extensive contamination of the outdoor environment. As part of this study, an assessment of the fleet of machines needed for decontaminating large outdoor surfaces of horizontal concrete will be attempted. The operations required are described. The performance of applicable existing equipment is analyzed in terms of area cleaned per unit time, and the comprehensive cost of decontamination per unit area is derived. Shielded equipment for measuring directional radiation and continuously monitoring decontamination work are described. Shielding of drivers' cabs and remote control vehicles is addressed.
Date: January 1, 1980
Creator: Barbier, M.M. & Chester, C.V.
Partner: UNT Libraries Government Documents Department

History of Met Lab Section C-I, May 1945 to May 1946

Description: This is the final volume of a history of the research work of Seaborg and associates in the University of Chicago Metallurgical Laboratory, Chemistry Section C-1. The work was concerned with the development of chemical procedures for the extraction of plutonium, for the purification of plutonium and, in the later phases, for research on the isotopes of other heavy elements including other transuranium elements. The style of the history is that of a diary with footnotes giving additional information.
Date: June 1, 1980
Creator: Seaborg, G.T.
Partner: UNT Libraries Government Documents Department

Frontiers of chemistry for americium and curium

Description: The discoveries of americium and curium were made only after Seaborg had formulated his actinide concept in order to design the chemistry needed to separate them from irradiated /sup 239/Pu targets. Their discoveries thus furnished the first clear-cut evidence that the series exists and justified Seaborg's bold assumption that even though Th and Pa appeared to presage a following 6d series, the pattern established by the periodic table after Cs and Ba would be repeated exactly after Fr and Ra. That is to say, a new 5f element rare earth series (the actinides) would follow Ac in the same way the 4f rare earth series (the lanthanides) follows La. The consequences of the resulting half-filled 5f/sup 7/ shell at Cm were originally presented by Seaborg as a test of his hypothesis. Recent research is outlined that substantiates Seaborg's predictions in new and definitive ways. 15 references, 4 figures.
Date: January 1, 1984
Creator: Keller, O.L. Jr.
Partner: UNT Libraries Government Documents Department

Valence instabilities as a possible source of actinide system inconsistencies

Description: The presence of a mixed-valence state in light actinides appears evident from the crystal structures of certain U, Np, and Pu phases. As supporting evidence, the physical property response of these actinide elements (and some of their alloys) is compared with that of rare-earth metallic compounds known to have an unstable valence. Impurities may stabilize an intermediate (different) valence state locally in rare-earth compounds in the presence of the valence state of the bulk phase. Impurity elements from different periodic table groupings may likewise stabilize different intermediate valence states in light actinide elements, thus contributing to inconsistencies in results reported by different experimentalists. Any model (theory) advanced for explaining the physical property behavior of U, Np, and Pu may also require consideration of a configurational limit. A phenomenological connection could exist between a martensitic transformation and the fluctuation temperature in both rare earth and actinide systems.
Date: August 1, 1979
Creator: Sandenaw, T.A.
Partner: UNT Libraries Government Documents Department

Hot cell for the synthesis of labelled organic compounds

Description: The design of a hot cell for use in labelling organic compounds is described. Versatility has been incorporated so that the cell can be used with a wide variety of organic syntheses as well as a large dynamic range of radioactivity (from ..mu..Ci to Ci levels). This is made possible by having the large work area easily accessible from the front which can be opened or closed and a small sliding lead glass window and master slave manipulator. A variety of syntheses setups which have been modified for use in such a cell are described.
Date: January 1, 1979
Creator: Fowler, J.S.; Karlstrom, K.; Koehler, C.; Lambrecht, R.M.; MacGregor, R.R.; Ruth, T.J. et al.
Partner: UNT Libraries Government Documents Department

Contaminated concrete surface layer removal

Description: Equipment is being developed to economically remove contaminated concrete surfaces in nuclear facilities. To be effective this equipment should minimize personnel radiation exposure, minimize the volume of material removed, and perform the operation quickly with the least amount of energy. Several methods for removing concrete surfaces are evaluated for use in decontaminating such facilities. Two unique methods especially suited for decontamination are described: one, the water cannon, is a device that fires a high-velocity jet of fluid causing spallation of the concrete surface; the other, a concrete spaller, is a tool that exerts radial pressure agains the sides of a pre-dilled shallow cylindrical hole causing spallation to occur. Each method includes a means for containing airborne contamination. Results of tests show that these techniques can rapidly and economically remove surfaces, and leave minimal rubble for controlled disposal.
Date: September 1, 1978
Creator: Halter, J. M. & Sullivan, R. G.
Partner: UNT Libraries Government Documents Department

Systematic view of optical absorption spectra in the actinide series

Description: In recent years sufficient new spectra of actinides in their numerous valence states have been measured to encourage a broader scale analysis effort than was attempted in the past. Theoretical modelling in terms of effective operators has also undergone development. Well established electronic structure parameters for the trivalent actinides are being used as a basis for estimating parameters in other valence states and relationships to atomic spectra are being extended. Recent contributions to our understanding of the spectra of 4+ actinides have been particularly revealing and supportive of a developing general effort to progress beyond a preoccupation with modelling structure to consideration of the much broader area of structure-bonding relationships. We summarize here both the developments in modelling electronic structure and the interpretation of apparent trends in bonding. 60 refs., 9 figs., 1 tab.
Date: January 1, 1985
Creator: Carnall, W.T.
Partner: UNT Libraries Government Documents Department

Guide to radiation fixatives

Description: This report identifies and then characterizes a variety of substances available in the market place for potential effectiveness as a fixative on radiologically contaminated surfaces. The substances include both generic chemicals and proprietary products. In selecting a fixative for a particular application, several attributes of the fixative may be relevant to the choice. These attributes include: toxicity, durability, and cleanliness and removability. In addition to the attributes of the fixative, one should also take into account certain characteristics of the site to be treated. These characteristics relate to climate, nature of the surface, use to which the treated surface will be put, subsequent cleanup operations, and type of neighboring surfaces. Finally, costs and potential environmental effects may influence the decision. A variety of fixatives are evaluated with respect to these various attributes and summarized in a reference table.
Date: November 1, 1983
Creator: Tawil, J.J. & Bold, F.C.
Partner: UNT Libraries Government Documents Department

Equilibria and thermodynamic properties of the plutonium-hydrogen system

Description: Equilibrium, kinetic and x ray diffraction data show the existence of two stability regimes in the Pu-H system. A metastable solid solution between CaF/sub 2/-type PuH/sub 1/ /sub 9/ and anti-Fe/sub 3/Al-type PuH/sub 3/ /sub 0/ forms at low temperature and behaves as an ideal solid solution. Equilibrium and calorimetric results show that the enthalpy of formation varies linearly from -38 to -50 kcal/mol between the lower phase boundary and the trihydride. The phase relationships established at high temperature are similar to those of the lanthanide difluoride-lanthanide trifluoride systems. A series of CaF/sub 2/-related phases apparently forms between PuH/sub 1/ /sub 9/ and PuH/sub 2/ /sub 5/; a nonstoichiometric hexagonal (LaF/sub 3/-type) hydride exists in the range PuH/sub 2/ /sub 9/-PuH/sub 3/ /sub 0/. A procedure for preparing pure hexagonal puH/sub 3/ /sub 00/ is described, and the hysteresis behavior of the Pu-H system is discussed.
Date: January 1, 1980
Creator: Haschke, J.M.; Hodges, A.E. III; Smith, C.M. & Oetting, F.L.
Partner: UNT Libraries Government Documents Department

Decommissioning of Division of Military Application equipment at Richland Operations Office for period ending June 30, 1975

Description: Decommissioning of the DMA facilities is estimated at 65% complete compared to 60% forecast at the start of the program in April 1974. The transfer of 12 transuranic boxes to 20-year retrievable storage this quarter brings the total to date to 26, and includes all of the inspection area glove boxes and conveyor sections, four A-Line and two C-Line glove boxes, along with all auxiliary hydraulic equipment pumps, and piping serving the three areas. Removal of additional A-Line and C-Line conveyor sections, one glove box, and relocation of two other glove boxes has been authorized by the Energy Research and Development Administration. Albuquerque Operations Office, and the A-Line portion of work currently is estimated at 40% complete. The removal of the one high plutonium-containing glove box, HC-40D and B has been delayed for additional sodium iodide (NaI) gamma counting following Z-Plant Operations cleanout and recovery of over 1,900 grams of plutonium. The fiscal year 1975 cost was $1,080,000 as estimated, and includes $11,585 in accrued costs for Fiberglass Reinforced Polyester (FRP) plywood boxes delivered but not billed at month-end. Thirty-eight of the 51 FRP boxes on order have been delivered to date, and the cost of $98,767 is included in the above fiscal year total.
Date: July 21, 1975
Partner: UNT Libraries Government Documents Department

Complex defects in the oxidation of uranium

Description: We are reporting EPR results obtained with uranium powder samples fully oxidized in dry air, water vapor, and air/water vapor mixtures. The results reported previously are confirmed and additional paramagnetic centers, associated with chemisorbed species, have been identified. The temperature dependence of the g-value for these centers from room temperature to 10K is also reported.
Date: June 10, 1986
Creator: MacCrone, R. K.; Sankaran, S.; Shatynski, S. R. & Colmenares, C. A.
Partner: UNT Libraries Government Documents Department

Survey of decontamination and decommissioning techniques

Description: Reports and articles on decommissioning have been reviewed to determine the current technology status and also attempt to identify potential decommissioning problem areas. It is concluded that technological road blocks, which limited decommissioning facilities in the past have been removed. In general, techniques developed by maintenance in maintaining the facility have been used to decommission facilities. Some of the more promising development underway which will further simplify decommissioning activities are: electrolytic decontamination which simplifies some decontaminating operations; arc saw and vacuum furnace which reduce the volume of metallic contaminated material by a factor of 10; remotely operated plasma torch which reduces personnel exposure; and shaped charges, water cannon and rock splitters which simplify concrete removal. Areas in which published data are limited are detailed costs identifying various components included in the total cost and also the quantity of waste generated during the decommissioning activities. With the increased awareness of decommissioning requirements as specified by licensing requirements, design criteria for new facilities are taking into consideration final decommissioning of buildings. Specific building design features will evolve as designs are evaluated and implemented.
Date: May 25, 1977
Creator: Kusler, L.E.
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

Kinetics of the ambient temperature dissolution of plutonium metal in sulfamic acid

Description: The stoichiometry and the kinetics of the ambient temperature dissolution of alpha-phase plutonium in sulfamic acid has been determined. Hydrogen off-gas rates and plutonium concentrations were calculated as functions of time for a variety of dissolving conditions. Calculations show that nominal 2.2 kg Pu buttons (surface area, 171 cm/sup 2/) should yield solutions containing 60 +- 10 g Pu/L after a one-hour dissolving cycle. Hydrogen off-gas rates were calculated to vary from as high as 780 mL of gaseous hydrogen per minute (STP) at the beginning of a dissolving cycle to as low as 150 mL H/sub 2/(g) per min near the end of a dissolving cycle.
Date: March 1, 1978
Creator: Gray, L.W.
Partner: UNT Libraries Government Documents Department

Chemical properties of the heavier actinides and transactinides

Description: The chemical properties of each of the elements 99 (Es) through 105 are reviewed and their properties correlated with the electronic structure expected for 5f and 6d elements. A major feature of the heavier actinides, which differentiates them from the comparable lanthanides, is the increasing stability of the divalent oxidation state with increasing atomic number. The divalent oxidation state first becomes observable in the anhydrous halides of californium and increases in stability through the series to nobelium, where this valency becomes predominant in aqueous solution. In comparison with the analogous 4f electrons, the 5f electrons in the latter part of the series are more tightly bound. Thus, there is a lowering of the 5f energy levels with respect to the Fermi level as the atomic number increases. The metallic state of the heavier actinides has not been investigated except from the viewpoint of the relative volatility among members of the series. In aqueous solutions, ions of these elements behave as a normal trivalent actinides and lanthanides (except for nobelium). Their ionic radii decrease with increasing nuclear charge which is moderated because of increased screening of the outer 6p electrons by the 5f electrons. The actinide series of elements is completed with the element lawrencium (Lr) in which the electronic configuration is 5f/sup 14/7s/sup 2/7p. From Mendeleev's periodicity and Dirac-Fock calculations, the next group of elements is expected to be a d-transition series corresponding to the elements Hf through Hg. The chemical properties of elements 104 and 105 only have been studied and they indeed appear to show the properties expected of eka-Hf and eka-Ta. However, their nuclear lifetimes are so short and so few atoms can be produced that a rich variety of chemical information is probably unobtainable.
Date: January 1, 1981
Creator: Hulet, E.K.
Partner: UNT Libraries Government Documents Department

I. The synthesis and characterization of annulated uranocenes. II. The variable temperature /sup 1/H NMR of uranocenes

Description: A general synthetic route to alkyl annulated cyclooctatetraene dianions and the corresponding annulated uranocenes has been developed. Dideprotonation of bicyclooctatrienes, resulting from reaction of cyclooctatetraene dianion with l,n-dialkylbromides or methanesulfonates, affords alkyl annulated cyclooctatetraene dianions in moderate yields. Dicyclopenteno-, bisdimethylcyclopenteno- and dicyclohexenouranocene were prepared from the corresponding cyclooctatetraene dianions and UCl/sub 4/. The structures of dicyclobuteno- and dicyclopentenouranocene were elucidated by single crystal X-ray diffraction, and the effects of annulation on the uranocene skeleton are discussed. Attempted synthesis of benzocyclooctatetraene and a benzannulated uranocene is reported. The variable temperature /sup 1/H NMR spectrum of uranocene has been reinvestigated from -100 to 100/sup 0/C. The isotropic shift was found to be linear in T/sup -1/ with an extrapolated intercept of 0 at T/sup -1/ = 0. Variable temperature /sup 1/H NMR spectra, from -80 to 70/sup 0/C, of 17 substituted uranocenes are reported. The energy barrier to ring rotation in 1,1', 4,4'-tetra-t-butyl-uranocene was determined to be 8.24 +- 0.5 kcal/mole while the barrier in the corresponding 1,1', 3,3'-tetra-t-butylferrocene was determined to be 13.1 kcal/mole. Alkyl substitution is shown to have little effect on the electronic and magnetic properties of the uranocene skeleton, and thus alkyl substituted uranocenes are treated as having effective axial symmetry in analysis of the observed isotropic shifts. Using diannulated uranocenes as model systems an analysis of the contact and pseudocontact components of the observed isotropic shifts in uranocene and alkyl substituted uranocenes is presented.
Date: January 1, 1980
Creator: Luke, W.D.
Partner: UNT Libraries Government Documents Department

Rapid automated nuclear chemistry

Description: Rapid Automated Nuclear Chemistry (RANC) can be thought of as the Z-separation of Neutron-rich Isotopes by Automated Methods. The range of RANC studies of fission and its products is large. In a sense, the studies can be categorized into various energy ranges from the highest where the fission process and particle emission are considered, to low energies where nuclear dynamics are being explored. This paper presents a table which gives examples of current research using RANC on fission and fission products. The remainder of this text is divided into three parts. The first contains a discussion of the chemical methods available for the fission product elements, the second describes the major techniques, and in the last section, examples of recent results are discussed as illustrations of the use of RANC.
Date: May 31, 1979
Creator: Meyer, R.A.
Partner: UNT Libraries Government Documents Department

Shifted homologous relationships between the transplutonium and early rare-earth metals

Description: The physico-chemical properties of the late actinide metals americium through einsteinium are compared with their rare-earth counterparts. Localization of the 5f electrons beginning at americium signals the appearance of true rare-earth-like properties, but the homologous relationship is shifted to place americium below praseodymium, einsteinium then below europium. The comparison of crystal structure, phase transitions, vapor pressures and heats of vaporization reveals remarkable similarities, especially for Sm-Cf and Eu-Es, where the stability of the divalent metal becomes established and divalent chemistry then follows. There is of course a major perturbation at the half-filled shell at curium, and it may be argued that americium is the anomaly in the so-called second rare-earth series. However, the response of americium, berkelium and californium under pressure reveals the true perturbation to be a thermodynamic one, occurring at curium.
Date: January 1, 1984
Creator: Ward, J.W.
Partner: UNT Libraries Government Documents Department

Kinetics for the reaction of hydrogen with uranium powder

Description: The reaction of hydrogen with uranium powder was investigated at 13.3 and 26.6 kPa between 50 and 250/sup 0/C. The reaction order was independent of temperature but varied from 2/3-order at 13.3 kPa to 1st-order at 26.6 kPa. Increasing temperatures resulted in decreasing reaction rates over the temperature range studied. A reaction mechanism with adsorption as the rate controlling step is proposed to explain the temperature behavior. Decomposition of the hydride was found to follow a zero-order rate process.
Date: January 1, 1979
Creator: Stakebake, J.L.
Partner: UNT Libraries Government Documents Department

Feasibility study for the oxidation of Am(III) by photolysis

Description: The results of a literature survey indicate that Am(III) may be light sensitive because it is characteristically similar to neptunium and plutonium. The redox potentials of americium are greater than the other two elements (which will probably make it more difficult to photolyze), and it does not absorb appreciable uv above 240 nm. A lamp whose emission is in the far uv region, a Suprasil quartz spectrophotometric-photolysis cell, and possibly an inert-atmosphere containment jacket would be needed to photolyze Am(III) in the glove box.
Date: December 1, 1980
Creator: Friedman, H.A.
Partner: UNT Libraries Government Documents Department