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Initial generation and separation of {sup 99}Mo at Sandia National Laboratories

Description: Medical isotopes play an important role in the medical industry in both the United States and the world. Isotopes such as {sup 99}Tc, {sup 201}Tl, {sup 111}In, and {sup 123}I are utilized in diagnostic imaging studies, while others such as {sup 131}I and {sup 89}Sr are used as therapeutic agents. The particular medical isotope {sup 99m}Tc is used in 80% of all nuclear medical procedures in the United States. This isotope is produced from the decay of {sup 99}Mo, which has a 66 hour half-life. The importance of {sup 99m}Tc and the fact of its 6 hour half-life indicate the necessity to maintain a constant supply of {sup 99}Mo. The most prominent method for the production of significant quantities of {sup 99}Mo is by fission in highly-enriched uranium loaded targets. This paper describes the work performed at SNL for the production of {sup 99}Mo.
Date: April 11, 1997
Creator: Talley, D.G.; Bourcier, S.C.; McDonald, M.J.; Longley, S.W. & Parma, E.J.
Partner: UNT Libraries Government Documents Department

Hanford single shell tank saltcake cesium removal test plan

Description: This document provides the test preparation and conduct of a cesium removal test using Hanford Single Shell Tank Saltcake from tanks 241-BY-110, 241-U-108, 241 U 109, 241-A-101, and 241-S-102 in a benchscale column. The cesium sorbent to be tested is crystalline silicotitanate
Date: December 11, 1996
Creator: Duncan, J.B., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Destruction of VX by aqueous-phase oxidation using peroxydisulfate (direct chemical oxidation)

Description: Chemical warfare agents may be completely destroyed (converted to H{sub 2}O, CO{sub 2}, salts) by oxidation at 90--100 C using acidified ammonium peroxydisulfate, with recycle of NH{sub 4}SO{sub 4} byproduct. The process requires no toxic or expended catalysts and produces no secondary wastes other than the precipitated inorganic content of the agents. To determine oxidative capability of peroxydisulfate at low reductant contents, we measured rate data for oxidation of 20 diverse compounds with diverse functional groups; 4 of these have bonds similar to those found in VX, HD, and GB. On an equivalence basis, integral first-order rate constants for 100 C oxidation are 0.012{plus_minus}0.005 min{sup {minus}1} for di-isopropyl-methyl-phosphonate, methyl phosphonic acid, triethylamine, and 2,2{prime}-thiodiethanol at low initial concentrations of 50 ppM(as carbon) and pH 1.5. To provide scale-up equations for a bulk chemical agent destruction process, we measured time-dependent oxidation of bulk model chemicals at high concentrations (0.5 N) and developed and tested a quantitative model. A practical process for bulk VX destruction would begin with chemical detoxification by existing techniques (eg, hydrolysis or mild oxidation using oxone), followed by mineralization of the largely detoxified products by peroxydisulfate. Secondary wastes would be avoided by use of commercial electrolysis equipment to regenerate the oxidant. Reagent requirements, mass balance and scaleup parameters are given for VX destruction, using peroxydisulfate alone, or supplemented with hydrogen peroxide. For the use of 2.5 N peroxydisulfate as the oxidant, a 1 m{sup 3} digester will process about 200 kg (as C) per day. The process may be extended to total destruction of HD and hydrolysis products of G agents.
Date: October 11, 1995
Creator: Cooper, J.F.; Krueger, R. & Farmer, J.C.
Partner: UNT Libraries Government Documents Department

Results of Scoping Studies for Determining Radiolytic Hydrogen Production from Moist CST and CST Slurries

Description: In support of the Salt Disposition team, scoping studies have been performed on the radiolysis of moist and aqueous slurries of Crystalline Silicotitanate(CST). If CST is used for removal of Cs-137 from SRS salt solutions, radiolysis of the water by Cs-137 on the CST will produce H2. Also it has been shown that the presence of a solid in the system can enhance the production of H2 by transferring absorbed energy from the solid to the water (1). As indicated in the test plan (2) for this scoping study, it is the intent of this study to determine if CST enhances the radiolytic production of H2 and to estimate the radiolytic hydrogen generation rate from an aqueous CST slurry in a column at the maximum expected Cs-137 loading on the CST.Initially several CST slurry systems were irradiated with Co-60 gamma rays and the radiolytic yield of H2 measured in terms of its G value (molecules of H2 produced per 100 eV of energy absorbed). Based on the results of these tests it was determined that CST did not enhance the radiolytic production of H2 by transferring energy to the water and causing it to decompose.Calculations were then performed to estimate the rate of H2 production from a process column 16ft. long by 5ft. in diameter containing CST that was fully loaded with Cs-137. The maximum rate of H2 production based on the G values measured in this study was one liter per minute at STP (0.04 cfm). This was for a 63 percent water/CST slurry with a G value of 0.2 molecules/100eV for H2 production and a loading of 1 gram of Cs-137 per 100 grams of resin. The present work also indicates that for a column containing salt solution and CST rather than water and CST, the rate would ...
Date: December 11, 1998
Creator: Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Preliminary waste form characteristics report Version 1.0. Revision 1

Description: This report focuses on radioactive waste form characteristics that will be used to design a waste package and an engineered barrier system (EBS) for a suitable repository as part of the Yucca Mountain Project. The term waste form refers to irradiated reactor fuel, other high-level waste (HLW) in various physical forms, and other radioactive materials (other than HLW) which are received for emplacement in a geologic repository. Any encapsulating of stabilizing matrix is also referred to as a waste form.
Date: October 11, 1991
Creator: Stout, R.B. & Leider, H.R.
Partner: UNT Libraries Government Documents Department

Solubility of Boron Compounds in Nitric Acid Solutions

Description: A series of laboratory experiments has been performed to determine flowsheet conditions for formation of boron solids during processing of glovebox floor sweepings (FS) and sand, slag, and crucible (S,S, and C) materials in canyon dissolvers. The precipitation of a boron compound (KBF4) was identified during the flowsheet development work for processing Rocky Flats S,S, and C materials at Savannah River. The subsequent series of laboratory experiments has focused on flowsheet conditions planned for the dissolution of glovebox floor sweepings in S,S, and C solutions.The concentrations of potassium fluoride (KF) and total fluoride were established where precipitation of boron solids would and would not occur during the processing of floor sweepings. Other variables such as changes in nitric acid and iron concentrations were found to have no impact on formation of boron solids. Results presented in Table 1 indicate that boron solids will not form at 0.22 molar KF and 0.30 molar total fluoride during processing of floor sweepings and at 0.22 molar KF and 0.32 molar total fluoride during processing of S,S, and C materials.
Date: December 11, 1998
Creator: Gray, J.H.
Partner: UNT Libraries Government Documents Department

Fundamental studies of matrix-assisted laser desorption/ionization, using time-of-flight mass spectrometry to identify biological molecules

Description: MALDI MS was developed as a way of getting molecular weight information on small quantities (picomole to femtomole levels) of high-mass, thermally labile macromolecules. While most other analytical MS ionization techniques cause fragmentation, decomposition, or multiple charging, MALDI efficiently places intact macromolecules into the gas phase with little fragmentation or rearrangement. This project had 3 objectives: establish the MALDI capability at LLNL, perform fundamental studies of analyte-matrix interactions, and apply the technique for biochemical research. A retired time-of-flight instrument was adapted for MALDI analyses, relevant parameters influencing the MALDI process were identified for further study (matrix molar absorptivity, sample crystal preparation), and collaborations were established with research groups in the Biology and Biotechnology Research Program at LLNL. In MALDI, the macromolecule of interest is mixed with a high-molar excess (1:100 to 1:10,000) of an organic matrix which readily absorbs energy at the wavelength corresponding to a UV laser. Upon laser irradiation, the matrix absorbs the majority of the energy, causing it to desorb from the surface and gently release the macromolecule into the gas phase with little or no fragmentation. Once in the gas phase, ion-molecule reactions between excited matrix and neutral macromolecules generated ionized analyte species which then can be focused into a MS for detection.
Date: November 11, 1996
Creator: Eades, D.; Wruck, D. & Gregg, H.
Partner: UNT Libraries Government Documents Department

Optically driven surface reactions: Laser probes of surface dynamics

Description: Our efforts in the past three and a half years have been directed towards providing the ground work for applying REMPI detection to the dynamics of surface oxidation and desorption reactions. Our initial efforts addressed the oxidation of carbon films that had been prepared on metal supports. The photolysis of adsorbed N{sub 2}O was chosen as the initial oxygen atom source. However, a number of alternative O atom precursors were also evaluated. Results from Auger electron spectroscopy (AES), temperature programmed desorption (TPD), and state-resolved studies of the photochemistry of N{sub 2}O, NO{sub 2}, or O{sub 2} coadsorbed with carbon on Pt(111) have been obtained. In the last eighteen months, we have focused on a stringent test of current theories of femtosecond laser-induced desorption of CO/Cu(100). The results indicate that an electronic friction model is sufficient to account for essentially all of the results in this system, indicating that a predictive tool for femtosecond laser-induced surface chemistry may be in hand.
Date: March 11, 1997
Creator: Cavanagh, R.R. & King, D.S.
Partner: UNT Libraries Government Documents Department

Different understanding: science through the eyes of visual thinkers

Description: The objective of this emergent study was to follow the cognitive and creative processes demonstrated by five art student participants as they integrated a developing knowledge of big science, as practiced at the Department of Energy`s Lawrence Livermore National Laboratory, into a personal and idiosyncratic visual, graphical, or multimedia product. The non-scientist participants involved in this process attended design classes sponsored by the Laboratory at the Art Center College of Design in California. The learning experience itself, and how the students arrived at their product, were the focus of the class and the research. The study was emergent in that we found no applicable literature on the use of art to portray a cognitive understanding of science. This lack of literature led us to the foundation literature on creativity and to the corpus of literature on public understanding of science. We believe that this study contributes to the literature on science education, art education, cognitive change, and public understanding of science. 20 refs., 11 figs.
Date: September 11, 1997
Creator: Sesko, S.C. & Marchant, M.
Partner: UNT Libraries Government Documents Department

Decomposition Studies of Triphenylboron, Diphenylborinic Acid and Phenylboric Acid in Aqueous Alkaline Solutions Containing Copper

Description: This report documents the copper-catalyzed chemical kinetics of triphenylboron, diphenylborinic acid and phenylboric acid (3PB, 2PB and PBA) in aqueous alkaline solution contained in carbon-steel vessels between 40 and 70 degrees C.
Date: February 11, 1997
Creator: Crawford, C.L. & Peterson, R. A.
Partner: UNT Libraries Government Documents Department

Polymerization of the E and Z Isomers of Bis-(Triethoxysilyl)-2-Butene

Description: We have synthesized the Z and E isomers of 1,4-bis(triethoxysilyl)-2- butene and polymerized them under acid and base catalyzed sol-gel conditions. As expected the E system formed crosslinked, insoluble gels. The Z isomer, by nature of its geometry, formed high molecular weight, soluble polymeric products under acidic conditions. We were able to prepare and isolate both the cyclic disilsesquioxane monomer, and its dimer. Comparison of their spectral characterization with that of the soluble polymers suggests that the cyclics are present within the polymers. lle synthesis of a dimer likely present at some early stage of the polymerization suggests that we may be able to control the reaction and form rigid polymers with controllable tacticity. In addition, most of the gels were found to be non-porous indicating that the gels were, in fact, more compliant than ethenylene-bridged polysilsesquioxanes leading to collapse of pores during drying.
Date: May 11, 1999
Creator: Carpenter, J.P. Dorhout, K.; Loy, D.A.; Shaltout, R.M. & Shea, K.J.
Partner: UNT Libraries Government Documents Department

Electronic Denitration Savannah River Site Radioactive Waste

Description: Electrochemical destruction of nitrate in radioactive Savannah River Site Waste has been demonstrated in a bench-scale flow cell reactor. Greater than 99% of the nitrate can be destroyed in either an undivided or a divided cell reactor. The rate of destruction and the overall power consumption is dependent on the cell configuration and electrode materials. The fastest rate was observed using an undivided cell equipped with a nickel cathode and nickel anode. The use of platinized titanium anode increased the energy requirement and costs compared to a nickel anode in both the undivided and divided cell configurations.
Date: April 11, 1995
Creator: Hobbs, D.T.
Partner: UNT Libraries Government Documents Department

Thermal degradation of poly({alpha}-methylstyrene) in solution. [Quarterly report, July--September 1995]

Description: The thermal degradation of poly({alpha}-methylstyrene) in solution was investigated at various temperatures (150-225 C) and polymer concentrations (2.00-20.0 g/L) at 6.8 MPa (1000 psig). The molecular weight distributions (MWDs) of the reacted polymer at these conditions were examined at four different residence times. Experimental data indicated that the polymer degraded to its monomer, {alpha}-methylstyrene. No other degradation products were observed. Continuous-mixture kinetics was used to examine the MWDs and to obtain the rate coefficient for degradation and its activation energy. The rate was first-order in polymer concentration with a rate constant at 225 C of 0.01 min{sup {minus} 1} and an activation energy of 66.5 kJ/mol (16.0 kcal/mol). The maximum conversion observed at 275 C was 1.2%. Hydrogen-donor solvent, tetralin, had no effect on the degradation.
Date: November 11, 1995
Creator: Madras, G.; Smith, J.M. & McCoy, B.J.
Partner: UNT Libraries Government Documents Department

Am/Cm Oxalate Precipitation and Washing Demonstration

Description: The purpose of this report is to discuss the findings of the Am/Cm Oxalate Precipitation and Washing Demonstration carried out at TNX during December 1995. This demonstration consisted of two steps: oxalate precipitation and precipitate washing. The first step reacted Am/Cm stimulant solution with oxalic acid resulting in the formation of insoluble lanthanide oxalates and soluble metal oxalates. The second step consisted of washing the precipitate with equal volumes of a nitric acid/oxalic acid solution to remove unwanted cations (miscellaneous metals) from the slurry. Quantitative results consist of: the solubility of the metallic impurities and lanthanide oxalates under process conditions, the settling rate of the oxalates, the specific volume of the oxalate precipitate, and the minimum distance the solution transfer jet can be place from the oxalate solids to prevent entrainment. Finally, discussion of how to decrease lanthanide losses is presented in terms of transfer jet location, initial nitric acid concentration, and wash nitric acid concentration. Solubilizing the precipitate and adjusting the nitric acid concentration prior to vitrification were not performed in this demonstration.
Date: June 11, 1996
Creator: Beck, S.B.
Partner: UNT Libraries Government Documents Department

Direct chemical oxidation of hazardous and mixed wastes

Description: Direct Chemical Oxidation (DCO) refers to the use of continuously-regenerated peroxydisulfate (with possible hydrogen peroxide supplements) to effect total destruction of organic wastes in aqueous media. The process does not involve toxic catalysts or the cogeneration of secondary wastes. Peroxydisulfate (S{sub 2}O{sub 8}{sup -2}) is one the strongest known chemical oxidants. It is routinely used in laboratory total carbon analyzers--uncatalyzed at 100{degrees}C, or catalyzed by UV, platinum or dissolved transition metal ions--and detects by oxidative destruction to 0.01 ppm levels. We report: (1) development of a waste treatment approach grounded in industrial electrolysis practice and in reaction rate data for Pt-initiated S{sub 2}O{sub 8}{sup -2} oxidation at 100{degrees}C; (2) tests of an electrochemical cell generating 1.5 N peroxydisulfate solutions; (3) lower-limit rate data for destruction of surrogates for chemical warfare agents and compounds with functional groups resisting oxidation; and (4) destruction of a Dowex{reg_sign} ion exchange resin, such as used in nuclear processing. This technique is particularly suited for applications in analytical laboratories or in manufacturing industries where the waste generation is low in volume, highly toxic or fugitive, or changing. The process may be tailored for destruction of very small to bulk quantities of chemical warfare agents.
Date: April 11, 1995
Creator: Cooper, J. F.; Wang, F. & Farmer, J.
Partner: UNT Libraries Government Documents Department

Reductions in the manufacturing cycle for the fluorination process of the 234-5 Building

Description: In the dry chemistry process of the Metal Fabrication Building, plutonium oxalate as received from the Isolation Building is converted to plutonium tetrafluoride and the fluoride is then reduced to the metal. This document discusses the oxalate-fluoride conversion which involves oxidation of the oxalate and subsequent fluorination of the oxide, utilizing anhydrous HF gas. Batch operation is practiced. The standard batch for the period covered by this report was 400 g Pu.
Date: October 11, 1954
Creator: Guenther, R.B.
Partner: UNT Libraries Government Documents Department

Technology development for cobalt F-T catalysts. Quarterly technical progress report No. 9, October 1, 1994--December 31, 1994

Description: The objective of this Project is to investigate the influence of various promoters, additives, and supports on minimizing the methane selectivity and increasing the water-gas shift (WGS) activity of cobalt (Co) Fischer-Tropsch (F-T) catalysts. The ultimate goal of this investigation is to identify and demonstrate a catalyst preparation Procedure that will be scaled up for the reproducible synthesis of commercial quantities of supported CO catalysts with desired activity, sleectivity, and lifetime for use in F-T synthesis in three-phase slurry bubble column reactors. Seven new catalysts were formulated and prepared during this period under both subtasks 1.2 and 1.3. Two more catalysts were prepared by Calsicat. The characterization of all the catalysts in order to determine their physical properties (BET surface area, pore volume, pore size diameter, particle size distribution), as well as the cobalt reducibility, extent of reduction, and dispersion) was continued. Fixed-bed reactor testing of the catalysts was continued. Six new catalysts were tested for their F-T synthesis performance. An investigation of the effect of pretreatment in various atmospheres (calcination in air or nitrogen prior to reduction in hydrogen, direct reduction without prior calcination, and reductiono)ddation-reduction (ROR)) of a selected number of catalysts upon their performance for F-T synthesis was continued during this period. Under subtask 2.2 during this reporting period a total of 11 runs were made in the two slurry bubble column reactors with eleven catalysts, including five on alumina, two from Calsicat, one WGS blend, and three on silica support. Four high CO conversion runs were made. Data were compiled to compare the CO conversions and product selectivities of the-methane reduction catalysts.
Date: May 11, 1995
Creator: Singleton, A.H.
Partner: UNT Libraries Government Documents Department

Nuclear interactions in high energy heavy ions and applications in astrophysics. [Dept. of Physics and Astronomy, Louisiana State Univ. , Baton Rouge]

Description: The overall objective is to study the mechanisms and the energy dependence of heavy ion fragmentation by studying the reactions of heavy ion projectiles (e.g. [sup 4]He, [sup 16]O, [sup 20]Ne, [sup 28]Si, [sup 56]Fe) in a variety of targets (H, He, C, Si, Cu, Pb) and at a number of beam energies exceeding 0.1 GeV/nucleon. The results have application to questions in high-energy nuclear astrophysics. Most of the discussion is on low-energy [sup 16]O,[sup 28]Si data analysis. The description includes analysis procedures and techniques, detector calibrations, data selections and normalizations. Cross section results for the analysis are also presented. 83 figs., 6 tabs., 73 refs.
Date: January 11, 1993
Creator: Wefel, J.P. & Guzik, T.G.
Partner: UNT Libraries Government Documents Department

Second test of base hydrolysate decomposition in a 0.04 gallon per minute scale reactor

Description: LLNL has built and operated a pilot plant for processing oil shale using recirculating hot solids. This pilot plant, was adapted in 1993 to demonstrate the feasibility of decomposing base hydrolysate, a mixture of sodium nitrite, sodium formate and other constituents. This material is the waste stream from the base hydrolysis process for destruction of energetic materials. In the Livermore process, the waste feed is thermally treated in a moving packed bed of ceramic spheres, where constituents in the waste decompose, in the presence of carbon dioxide, to form solid sodium carbonate and a suite of gases including: methane, carbon monoxide, oxygen, nitrogen oxides, ammonia and possibly molecular nitrogen. The ceramic spheres are circulated and heated, providing the energy required for thermal decomposition. The spheres provide a large surface area for evaporation and decomposition to occur, avoiding sticking and agglomeration of the waste. We performed a 2.5 hour test of the solids recirculation system, with continuous injection of approximately 0.04 gal/min of waste. Gasses from the packed bed reactor were directed through the lift pipe and water was not condensed. Potassium carbonate (0.356 M) was added to the hydrolysate prior to its introduction to the retort. Continuous on-line gas analysis was invaluable in tracking the progress of the experiment and quantifying the decomposition products. Analyses showed the primary solid product, collected in the lift exit cyclone, was indeed sodium carbonate, as expected. For the reactor condition studied in this test, N{sub 2}O was found to be the primary nitrogen bearing gas species. In the test, approximately equal quantities of ammonia and nitrogen bearing oxide gases were produced. Under proper conditions, this ammonia and NO{sub x} can be recombined downstream to form N{sub 2} and O{sub 2} as the primary effluent gases.
Date: October 11, 1994
Creator: Cena, R.J.; Thorsness, C.B.; Coburn, T.T. & Watkins, B.E.
Partner: UNT Libraries Government Documents Department

Nuclear interactions in high energy heavy ions and applications in astrophysics. Technical progress report, 1 April 1992--31 March 1993

Description: The overall objective is to study the mechanisms and the energy dependence of heavy ion fragmentation by studying the reactions of heavy ion projectiles (e.g. {sup 4}He, {sup 16}O, {sup 20}Ne, {sup 28}Si, {sup 56}Fe) in a variety of targets (H, He, C, Si, Cu, Pb) and at a number of beam energies exceeding 0.1 GeV/nucleon. The results have application to questions in high-energy nuclear astrophysics. Most of the discussion is on low-energy {sup 16}O,{sup 28}Si data analysis. The description includes analysis procedures and techniques, detector calibrations, data selections and normalizations. Cross section results for the analysis are also presented. 83 figs., 6 tabs., 73 refs.
Date: January 11, 1993
Creator: Wefel, J. P. & Guzik, T. G.
Partner: UNT Libraries Government Documents Department