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Radiation Stability Studies

Description: From abstract: "An investigation of the radiation stabilities of aqueous solutions of sodium ethylenediamine tetraacetate and sodium acetate was made using a 3000-curie Co⁶⁰ source...A study of the behavior of the standard-size Beckman type glass pH electrodes in a solution containing 0.36 curie of Ce¹⁴⁴-Pr¹⁴⁴ activity per milliliter showed the useful electrode life to be of the order of two to eight days."
Date: September 22, 1952
Creator: Blanco, R. E.; Kibbey, A. H. & Pannell, J. H.
Partner: UNT Libraries Government Documents Department


Description: The reaction rate of sodium sulfite was studied as a function of oxygen concentration, Na/sub 2/SO/sub 3//O/sub 2/ ratio, temperature, catalyst, pH and surface/volume ratio.The reaction rate of hydrazine with dissolved oxygen was also studied. Oxygen removal is incomplete when the sulfite to oxygen ratio is leas than the stoichiometric quantity. With the stoichiometric quantities of oxygen and sodium sulfite present, removal is incomplete at 100 deg F in 1 min, at 200 deg F, about 95% of the oxygen is removed in 10 sec and at 300 deg F oxygen removal is essentially complete in 10 sec. With an excess of sulfite present (10 Na/sub 2/SO/sub 3//1 O/sub 2/, molar), 95% of the oxygen is removed at 100 deg F in 10 sec. At 200 and 300 deg F, oxygen removal is essentially complete in 10 sec. The rate of oxygen removal is dependent to some extent on the container material. The sulfite oxygen reaction progresses at a higher rate in boiler water than in feedwater. The reaction rate of hydrazine with oxygen is low compared with the reaction rate of sulfite and dissolved oxygen. No reduction of oxygen was noted over a one-minute period with an excess of hydrazine. (auth)
Date: May 16, 1960
Creator: Rodgers, S.J.
Partner: UNT Libraries Government Documents Department

Solubilities of significant compounds in HLW tank supernate solutions - FY 1996 progress report

Description: The solubilities of two sodium salts of organic acids that are thought to exist in high-level waste at the Hanford Site were measured in tank supernate simulant solutions during FY1996 This solubility information will be used to determine if these organic salts could exist in solid phases (saltcake or sludges) in the waste where they might react violently with the nitrate or nitrite salts present in the tanks. Solubilities of sodium butyrate and trisodium N-(2-hydroxyethyl)ethylenediaminetriacetate were measured in simulated waste supernate solutions at 25 {degrees}C, 30 {degrees}C, 40 {degrees}C, and 50 {degrees}C. The organic compounds were selected because they are expected to exist in relatively high concentrations in the tanks. Two types of tank supernate simulants were used - a 4.O M sodium nitrate - 0.97 M sodium nitrite solution with sodium hydroxide concentrations ranging from O.00003 M to 2.O M and a 2.O M sodium nitrite solution saturated with crystalline sodium nitrate with sodium hydroxide concentrations ranging from 0.1 M to 2. 0 M. The solubilities of sodium butyrate and trisodium N-(2-hydroxyethyl)ethylene- diaminetriacetate in both types of HLW tank supernate solutions were high over the temperature and sodium hydroxide concentration ranges expected in the tanks. The solubilities of these compounds are similar (in terms of total organic carbon) to sodium glycolate, succinate, caproate, dibutylphosphate, citrate, formate, ethylenediaminetetraacetate, and nitrilotriacetate which were measured previously. High solubilities will prevent solid sodium salts of these organic acids from precipitating from tank supernate solutions. The total organic carbon concentrations (TOC) of actual tank supernates are generaly much lower than the TOC ranges for the simulated supernate solutions saturated (at the solubility limit) with the organic salts. This is true even if all the dissolved carbon in a given tank supernate is due to only one of these eight soluble compounds (an unlikely situation). ...
Date: September 30, 1996
Creator: Barney, G.S.
Partner: UNT Libraries Government Documents Department

Excess Sodium Tetraphenylborate and Intermediates Decomposition Studies

Description: The stability of excess amounts of sodium tetraphenylborate (NaTPB) in the In-Tank Precipitation (ITP) facility depends on a number of variables. Concentration of palladium, initial benzene, and sodium ion as well as temperature provide the best opportunities for controlling the decomposition rate. This study examined the influence of these four variable on the reactivity of palladium-catalyzed sodium tetraphenylborate decomposition. Also, single effects tests investigated the reactivity of simulants with continuous stirring and nitrogen ventilation, with very high benzene concentrations, under washed sodium concentrations, with very high palladium concentrations, and with minimal quantities of excess NaTPB.
Date: December 7, 1998
Creator: Barnes, M.J.
Partner: UNT Libraries Government Documents Department

Structure of charged polymer chains in confined geometry.

Description: The intra- and interchain structure of sodium poly(styrenesulphonate) when free and when confined in contrast matched porous Vycor has been investigated by SANS. When confined, a peak is observed whose intensity increases with molecular weight and the 1/q scattering region is extended compared to the bulk. We infer that the chains are sufficiently extended, under the influence of confinement, to highlight the large scale disordered structure of Vycor. The asymptotic behavior of the observed interchain structure factor is = 1/q{sup 2} and = 1/q for free and confined chains respectively.
Date: December 15, 2000
Creator: Gilbert, E. P.; Auvray, L. & Lal, J.
Partner: UNT Libraries Government Documents Department

Corrosion mechanisms of spent fuel under oxidizing conditions

Description: The release of {sup 99}Tc can be used as a reliable marker for the extent of spent oxide fuel reaction under unsaturated high drip rate conditions at 90{degrees}C. Evidence from the leachate data and from scanning and transmission electron microscopy (SEM and TEM) examination of reacted fuel samples is presented for radionuclide release, potential reaction pathways, and the formation of alteration products. In the ATM-103 fuel, 0.03 of the total inventory of {sup 99}Tc is release in 3.7 years under unsaturated and oxidizing conditions. Two reaction pathways that have been identified from SEM are (1) through-grain dissolution with subsequent formation of uranyl alteration products, and (2) grain-boundary dissolution. The major alteration product identified by X-ray diffraction (XRD) and SEM, is Na-boltwoodite, Na[(UO{sub 2})(SiO{sub 3}OH)].H{sub 2}O, which is formed from sodium and silicon in the water leachant.
Date: September 1, 1997
Creator: Finn, P. A.; Finch, R. J.; Buch, E. C. & Bates, J. K.
Partner: UNT Libraries Government Documents Department

Densities of Sodium Tetrafluoroborate Aqueous Solutions at 20 Degrees C

Description: Analytical data and plant solution compositions are often reported in molarity units. Densities of salt solutions are needed to convert the concentrations to molal basis in order to utilize physical property data that have been established on a molal basis, for example, solution reaction equilibrium constants or activity coefficients. We report here the densities at 20.0 Degrees C of sodium tetrafluoroborate (NaBF4) solutions from 0.05 molal to 9.0 molal, near saturation of 9.2 molal.
Date: July 9, 2002
Creator: Crooks, W.J. III
Partner: UNT Libraries Government Documents Department

The Suitability of Sodium Peroxide Fusion for Production-Scale Plutonium Processing Operations

Description: Sodium peroxide (Na{sub 2}O{sub 2}) fusion is a method that offers significant benefits to the processing of high-fired plutonium oxide (PuO{sub 2}) materials. Those benefits include reduction in dissolution cycle time, decrease in residual solids, and reduction of the potential for generation of a flammable gas mixture during dissolution. Implementation of Na{sub 2}O{sub 2} fusion may also increase the PuO{sub 2} throughput in the HB-Line dissolving lines. To fuse a material, Na{sub 2}O{sub 2} is mixed with the feed material in a crucible and heated to 600-700 C. For low-fired and high-fired PuO{sub 2}, Na{sub 2}O{sub 2} reacts with PuO{sub 2} to form a compound that readily dissolves in ambient-temperature nitric acid without the use of potassium fluoride. The Savannah River National Laboratory (SRNL) demonstrated the feasibility of Na{sub 2}O{sub 2} fusion and subsequent dissolution for the processing of high-fired PuO{sub 2} materials in HB-Line. Testing evaluated critical dissolution characteristics and defined preliminary process parameters. Based on experimental measurements, a dissolution cycle can be complete in less than one hour, compared to the current processing time of 6-10 hours for solution heating and dissolution. Final Pu concentrations of 30-35 g/L were produced without the formation of precipitates in the final solution.
Date: October 26, 2010
Creator: Pierce, R. & Edwards, T.
Partner: UNT Libraries Government Documents Department

Kinetics and Equilibrium Sorption Models: Fitting Plutonium, Strontium, Uranium and Neptunium Loading on Monosodium Titanate (MST)

Description: The Dubinin-Astashov (DA) isotherm parameters for U, Pu, Sr and Np have been updated to include additional data obtained since the original derivation. The DA isotherms were modified to include a kinetic function derived by Rahn to describe sorbate loading from the beginning of sorption up to steady state. The final functions describe both kinetic and thermodynamic sorption.
Date: March 8, 2006
Creator: Fondeur, F
Partner: UNT Libraries Government Documents Department

Coagulation chemistries for silica removal from cooling tower water.

Description: The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling tower water, with and without flocculation aids, at concentrations typical for water purification with limited results. In Phase II, it was decided that treatment of source or make up water was more appropriate, and that higher dosing with coagulants delivered promising results. In fact, the less exotic coagulants proved to be more efficacious for reasons not yet fully determined. Some analysis was made of the molecular nature of the precipitated floc, which may aid in process improvements. In Phase III, more detailed study of process conditions for aluminum chloride coagulation was undertaken. Lime-soda water softening and the precipitation of magnesium hydroxide were shown to be too limited in terms of effectiveness, speed, and energy consumption to be considered further for the present application. In Phase IV, sodium aluminate emerged as an effective coagulant for silica, and the most attractive of those tested to date because of its availability, ease of use, and low requirement for additional chemicals. Some process optimization was performed for coagulant concentration and operational pH. It is concluded that silica coagulation with simple aluminum-based agents is effective, simple, and compatible with other industrial processes.
Date: February 1, 2010
Creator: Nyman, May Devan; Altman, Susan Jeanne & Stewart, Tom
Partner: UNT Libraries Government Documents Department


Description: Evaluation of dry films for application on spur gears for - servicing components of a gas-cooled nuclear reactor was performed. Commercial dry film lubricants were screened in wear tests to obtain the optimum lubricant which was in turn used in gear teats. A MoS/sub 2/, graphite, and sodium silicate binder lubricant (Everlube 811 or equivalent) applied to M 50 tool steel gears resulted in the optimum combination based on stress cycle tests. Tests were performed on uniubricated worm gears at simulated loads, speeds, and environment of the charging machine for the above reactor to determine wear rates and efficiencies. (auth)
Date: April 30, 1961
Creator: Fessett, D.J.
Partner: UNT Libraries Government Documents Department


Description: This report describes the results from RPP-PLAN-32738, 'Test Plan for the Effluent Treatment Facility to Reduce Chrome(VI) to Chrome(I1I) in the Secondary Waste Stream', using sodium metabisulfite. Appendix A presents the report as submitted by the Center for Laboratory Sciences (CLS) to CH2M HILL Hanford Group, Inc. The CLS carried out the laboratory effort under Contract Number 21065, release Number 30. This report extracts the more pertinent aspects of the laboratory effort.
Date: July 18, 2007
Partner: UNT Libraries Government Documents Department

In situ XANES study of the passive film formed on iron in borate buffer and in sodium acetate

Description: The passive film formed on Fe in pH 8.4 borate buffer (0. 1 36 M) over a broad potential range was characterized by in situ XANES (x-ray absorption near edge structure). On stepping the potential to a value between -0.6 V and +0.4 V (MSE), a passive film forms without detectable dissolution. The edge position indicates that the valence state of Fe in the film is 10 {+-} 5% Fe{sup 2+} and 90 {+-} 5% Fe{sup 3+}. Formation of a passive film at potentials between -0.8 V and -0.65 V is associated with dissolution prior to passivation, and a lower average valence state of 17 {+-} 5% Fe{sup 2+} and 83 {+-} 5% Fe{sup 3+}. At -0.9 V, the Fe did not passivate. The passive film that forms in pH 8.2 sodium acetate (0.1 M) at +0.4 V gives an edge similar to the high potential passive film formed in borate buffer, but dissolution occurs prior to passivation.
Date: December 31, 1996
Creator: Oblonsky, L.J.; Ryan, M.P. & Isaacs, S.
Partner: UNT Libraries Government Documents Department