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Defense waste processing facility startup progress report

Description: The Savannah River Site (SRS) has been operating a nuclear fuel cycle since the 1950's to produce nuclear materials in support of the national defense effort. About 83 million gallons of high level waste produced since operation began have been consolidated into 33 million gallons by evaporation at the waste tank farm. The Department of Energy has authorized the construction of the Defense Waste Processing Facility (DWPF) to immobilize the waste as a durable borosilicate glass contained in stai… more
Date: January 1, 1992
Creator: Iverson, D.C. & Elder, H.H.
Partner: UNT Libraries Government Documents Department
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Plutonium(IV) hydrous polymer chemistry

Description: The hydrous polymer chemistry of Pu(IV) in aqueous nitric acid solutions has been a subject of considerable interest for several years. This interest stems mainly from the fact that most nuclear fuel reprocessing schemes based on the Purex process can be hampered by the occurrence of polymer. As a result, an understanding and control of the parameters that affect polymer formation during reprocessing are studied. 2 refs.
Date: January 1, 1985
Creator: Toth, L.M. & Dodson, K.E.
Partner: UNT Libraries Government Documents Department
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A comparison of glass reaction at high and low SA/V: PCT vs MCC-1

Description: Leach tests have been performed at surface area/volume (SA/V) of 10, 2000, and 20,000 m{sup {minus}1} using actinide-doped borosilicate waste glass (SRL 131 and SRL 202) to assess the effects of the SA/V on the mechanism and rate of the glass reaction. Solution results are presented which show the major effect of the SA/V to be dilution. Higher SA/V result in higher leachate pH values being attained due to initial ion exchange reactions. The higher pH values then accelerate hydrolysis of the gl… more
Date: January 1, 1992
Creator: Ebert, W.L. & Bates, J.K.
Partner: UNT Libraries Government Documents Department
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Defense waste processing facility precipitate hydrolysis process

Description: Sodium tetraphenylborate and sodium titanate are used to assist in the concentration of soluble radionuclide in the Savannah River Plant's high-level waste. In the Defense Waste Processing Facility, concentrated tetraphenylborate/sodium titanate slurry containing cesium-137, strontium-90 and traces of plutonium from the waste tank farm is hydrolyzed in the Salt Processing Cell forming organic and aqueous phases. The two phases are then separated and the organic phase is decontaminated for … more
Date: March 1, 1986
Creator: Doherty, J P; Eibling, R E & Marek, J C
Partner: UNT Libraries Government Documents Department
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High level nuclear waste treatment in the Defense Waste Processing Facility: Overview and integrated flowsheet model

Description: Design and construction of the world's largest vitrification facility for high level nuclear waste has been nearly completed at the US Department of Energy's Savannah River Site. Equipment testing and calibration are currently being performed in preparation for the nonradioactive Chemical Runs in the late 1991. In 1993, the Defense Waste Processing Facility (DWPF) will begin producing 100 kg/hr of radioactive waste glass at 28 wt% waste oxide loading. This paper describes all phases of waste pr… more
Date: January 1, 1991
Creator: Choi, A. S.; Fowler, J. R.; Edwards, R. E. Jr. & Randall, C. T.
Partner: UNT Libraries Government Documents Department
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Aqueous chemistry of iodine

Description: The chemistry of iodine has been examined in aqueous solutions of pH 6 to 10 containing 2500 ppM boron as H/sub 3/BO/sub 3/ at temperatures up to 150/sup 0/C using absorption spectrophotometry to identify and monitor the iodine species present. Kinetic rate constants for the disproportionation of the HOI intermediate, 3HOI= IO/sub 3//sup -/ + 2I/sup -/ + 3H/sup +/, have been measured as a function of pH even though no direct spectral evidence for HOI itself has been observed. An HOI partition c… more
Date: January 1, 1984
Creator: Toth, L.M.; Pannell, K.D. & Kirkland, O.L.
Partner: UNT Libraries Government Documents Department
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Pilot scale processing of simulated Savannah River Site high level radioactive waste

Description: The Savannah River Laboratory operates the Integrated DWPF Melter System (IDMS), which is a pilot-scale test facility used in support of the start-up and operation of the US Department of Energy's Defense Waste Processing Facility (DWPF). Specifically, the IDMS is used in the evaluation of the DWPF melter and its associated feed preparation and offgass treatment systems. This article provides a general overview of some of the test work which has been conducted in the IDMS facility. The chemistr… more
Date: January 1, 1991
Creator: Hutson, N. D.; Zamecnik, J. R.; Ritter, J. A. & Carter, J. T.
Partner: UNT Libraries Government Documents Department
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Studies of the hydrolytic and gamma-radiolytic degradation of the TRUEX-CC1/sub 4/ process solvent

Description: The stability of the TRUEX-CCl/sub 4/ solvent (0.25M OphiD(iB)CMPO-0.75M TBP-CCl/sub 4/) toward hydrolytic and gamma-radiolytic degration is presently under study. The experimental procedure is discussed. Reported this quarter are the complete results for experiments run at 50/sup 0/C to measure the nitric-acid-catalyzed degradation of the TRUEX-CCl/sub 4/ solvent and the partial results for hydrolytic degradation experiments run at 70/sup 0/C and gamma-radiolytic degradation experiments run at… more
Date: May 1, 1985
Creator: Vandegrift, G.
Partner: UNT Libraries Government Documents Department
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Metagenomic and Functional Analysis of Hindgut Microbiota of a Wood-Feeding Higher Termite

Description: From the standpoints of both basic research and biotechnology, there is considerable interest in reaching a clearer understanding of the diversity of biological mechanisms employed during lignocellulose degradation. Globally, termites are an extremely successful group of wood-degrading organisms and are therefore important both for their roles in carbon turnover in the environment and as potential sources of biochemical catalysts for efforts aimed at converting wood into biofuels. Only recently… more
Date: October 1, 2007
Creator: Warnecke, Falk; Warnecke, Falk; Luginbuhl, Peter; Ivanova, Natalia; Ghassemian, Majid; Richardson, Toby H. et al.
Partner: UNT Libraries Government Documents Department
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SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

Description: N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the requi… more
Date: June 9, 2008
Creator: Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.; Johnson, Francis & Huang, Bo
Partner: UNT Libraries Government Documents Department
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Lactonization and protonation of gluconic acid: a thermodynamicand kinetic study by potentiometry, nmr and esi-ms

Description: In acidic aqueous solutions, gluconate protonation is coupled with lactonization of gluconic acid. With the decrease of pC{sub H}, two lactones ({delta}/{gamma}) are sequentially formed. The {delta}-lactone forms more readily than the {gamma}-lactone. In 0.1 M gluconate solutions, if pC{sub H} is above 2.5, only the {delta}-lactone is generated. When pC{sub H} is decreased below 2.0, the formation of the {gamma}-lactone is observable although the {delta}-lactone predominates. At I = 0.1 M NaClO… more
Date: January 10, 2007
Creator: Zhang, Z.; Gibson, P.; Clark, S.B.; Tian, G.; Zanonato, P. & Rao, L.
Partner: UNT Libraries Government Documents Department
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Damp-Heat Induced Degradation of Transparent Conducting Oxides for Thin-Film Solar Cells: Preprint

Description: The stability of intrinsic and Al-doped single- and bi-layer ZnO for thin-film CuInGaSe2 solar cells, along with Al-doped Zn1-xMgxO alloy and Sn-doped In2O3 (ITO) and F-doped SnO2, was evaluated by direct exposure to damp heat (DH) at 85oC and 85% relative humidity. The results show that the DH-induced degradation rates followed the order of Al-doped ZnO and Zn1-xMgxO >> ITO > F:SnO2. The degradation rates of Al:ZnO were slower for films of higher thickness, higher substrate temperature in sput… more
Date: May 1, 2008
Creator: Pern, F. J.; Noufi, R.; Li, X.; DeHart, C. & To, B.
Partner: UNT Libraries Government Documents Department
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Fluorine for Hydrogen Exchange in the Hydrofluorobenzene Derivatives C6HxF(6-x), where x = 2, 3, 4 and 5 by Monomeric [1,2,4-(Me3C)3C5H2]2CeH; The Solid State Isomerization of [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,5-C6HF4) to [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,6-C6HF4)

Description: The reaction between monomeric bis(1,2,4-tri-t-butylcyclopentadienyl)cerium hydride, Cp'2CeH, and several hydrofluorobenzene derivatives is described. The aryl derivatives that are the primary products, Cp'2Ce(C6H5-xFx) where x = 1,2,3,4, are thermally stable enough to be isolated in only two cases, since all of them decompose at different rates to Cp'2CeF and a fluorobenzyne; the latter is trapped by either solvent when C6D6 is used or by a Cp'H ring when C6D12 is the solvent. … more
Date: April 21, 2008
Creator: Andersen, Richard; Werkema, Evan L. & Andersen, Richard A.
Partner: UNT Libraries Government Documents Department
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Structural Formation Studies of UV-Catalyzed Gels and Aerogels by Light Scattering

Description: The skeletal structure of aerogel is determined before, during, and after the gel is formed. Supercritical drying of aerogel largely preserves the pore structure that is determined near the time of gelation. To better understand these gel formation mechanisms we carried out measurements of the time evolution of light scattering in a series of gels prepared without conventional acid or base catalysis. Instead, ultraviolet light was used to catalyze the formation of silica gels made from the hydr… more
Date: April 1, 1998
Creator: Hunt, Arlon J. & Ayers, Michael R.
Partner: UNT Libraries Government Documents Department
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TRANSITION STATE FOR THE GAS-PHASE REACTION OF URANIUM HEXAFLUORIDE WITH WATER

Description: Density Functional Theory and small-core, relativistic pseudopotentials were used to look for symmetric and asymmetric transitions states of the gas-phase hydrolysis reaction of uranium hexafluoride, UF{sub 6}, with water. At the B3LYP/6-31G(d,p)/SDD level, an asymmetric transition state leading to the formation of a uranium hydroxyl fluoride, U(OH)F{sub 5}, and hydrogen fluoride was found with an energy barrier of +77.3 kJ/mol and an enthalpy of reaction of +63.0 kJ/mol (both including zero-po… more
Date: March 18, 2008
Creator: Garrison, S & James Becnel, J
Partner: UNT Libraries Government Documents Department
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Degradation of ZnO Window Layer for CIGS by Damp-Heat Exposure: Preprint

Description: This paper summarizes our work with more details and an emphasis on the DH-induced degradation of Al-doped ZnO and Zn1-xMgxO alloys. The other two TCOs, ITO and F:SnO2, are not included here.
Date: August 1, 2008
Creator: Pern, F.J.; To, B.; DeHart, C.; Li, X.; Glick, S. H. & Noufi, R.
Partner: UNT Libraries Government Documents Department
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Near-Monodisperse Ni-Cu Bimetallic Nanocrystals of Variable Composition: Controlled Synthesis and Catalytic Activity for H2 Generation

Description: Near-monodisperse Ni{sub 1-x}Cu{sub x} (x = 0.2-0.8) bimetallic nanocrystals were synthesized by a one-pot thermolysis approach in oleylamine/1-octadecene, using metal acetylacetonates as precursors. The nanocrystals form large-area 2D superlattices, and display a catalytic synergistic effect in the hydrolysis of NaBH{sub 4} to generate H{sub 2} at x = 0.5 in a strongly basic medium. The Ni{sub 0.5}Cu{sub 0.5} nanocrystals show the lowest activation energy, and also exhibit the highest H{sub 2}… more
Date: July 22, 2008
Creator: Zhang, Yawen; Huang, Wenyu; Habas, Susan E.; Kuhn, John N.; Grass, Michael E.; Yamada, Yusuke et al.
Partner: UNT Libraries Government Documents Department
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Acid Catalysis in Basic Solution: A Supramolecular Host PromotesOrthoformate Hydrolysis

Description: Though many enzymes can promote chemical reactions by tuning substrate properties purely through the electrostatic environment of a docking cavity, this strategy has proven challenging to mimic in synthetic host-guest systems. Here we report a highly-charged, water soluble, metal-ligand assembly with a hydrophobic interior cavity that thermodynamically stabilizes protonated substrates and consequently catalyzes the normally acidic hydrolysis of orthoformates in basic solution, with rate acceler… more
Date: December 12, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
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Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water

Description: Understanding the solution behavior of supramolecular assemblies is essential for a full understanding of the formation and chemistry of synthetic host-guest systems. While the interaction between host and guest molecules is generally the focus of mechanistic studies of host-guest complexes, the interaction of the host-guest complex with other species in solution remains largely unknown, although in principle accessible by diffusion studies. Several NMR techniques are available to monitor diffu… more
Date: October 22, 2007
Creator: University of California, Berkeley; Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Pluth, Michael D.; Tiedemann, Bryan E.F.; van Halbeek, Herman et al.
Partner: UNT Libraries Government Documents Department
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Catalytic Deprotection of Acetals In Strongly Basic Solution Usinga Self-Assembled Supramolecular 'Nanozyme'

Description: Acetals are among the most commonly used protecting groups for aldehydes and ketones in organic synthesis due to their ease of installation and resistance to cleavage in neutral or basic solution.[1] The common methods for hydrolyzing acetals almost always involve the use of either Broensted acid or Lewis acid catalysts.[2] Usually aqueous acids or organic solutions acidified with organic or inorganic acids have been used for reconversion of the acetal functionality to the corresponding carbony… more
Date: July 26, 2007
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
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THE HYDROLYSIS AND OXIDATION BEHAVIOR OF LITHIUM BOROHYDRIDE AND MAGNESIUM HYDRIDE DETERMINED BY CALORIMETRY

Description: Lithium borohydride, magnesium hydride and the 2:1 'destabilized' ball milled mixtures (2LiBH{sub 4}:MgH{sub 2}) underwent liquid phase hydrolysis, gas phase hydrolysis and air oxidation reactions monitored by isothermal calorimetry. The experimentally determined heats of reaction and resulting products were compared with those theoretically predicted using thermodynamic databases. Results showed a discrepancy between the predicted and observed hydrolysis and oxidation products due to both kine… more
Date: March 13, 2008
Creator: Brinkman, K; Donald Anton, D; Joshua Gray, J & Bruce Hardy, B
Partner: UNT Libraries Government Documents Department
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Variational transition state theory calculations of tunneling effects on concerted hydrogen motion in water clusters and formaldehyde/water clusters

Description: The direct participation of water molecules in aqueous phase reaction processes has been postulated to occur via both single-step mechanisms as well as concerted hydrogen atom or proton shifts. In the present work, simple prototypes of concerted hydrogen atom transfer processes are examined for small hydrogen-bonded water clusters -- cyclic trimers and tetramers -- and hydrogen-bonded clusters of formaldehyde with one and two water molecules. Rate constants for the rearrangement processes are c… more
Date: August 1, 1990
Creator: Garrett, B.C. (Pacific Northwest Lab., Richland, WA (USA)) & Melius, C.F. (Sandia National Labs., Livermore, CA (USA))
Partner: UNT Libraries Government Documents Department
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Testing of nuclear grade lubricants and their effects on A540 B24 and A193 B7 bolting materials

Description: An investigation was performed on eleven commonly used lubricants by the nuclear power industry. The investigation included EDS analysis of the lubricants, notched-tensile constant extension rate testing of bolting materials with the lubricants, frictional testing of the lubricants and weight loss testing of a bonded solid film lubricant. The report generally concludes that there is a significant amount of variance in the mechanical properties of common bolting materials; that MoS/sub 2/ can hy… more
Date: January 1, 1985
Creator: Czajkowski, C.J.
Partner: UNT Libraries Government Documents Department
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Plutonium waste incineration using pyrohydrolysis

Description: Waste generated by Savannah River Site (SRS) plutonium operations includes a contaminated organic waste stream. A conventional method for disposing of the organic waste stream and recovering the nuclear material is by incineration. When the organic material is burned, the plutonium remains in the incinerator ash. Plutonium recovery from incinerator ash is highly dependent on the maximum temperature to which the oxide is exposed. Recovery via acid leaching is reduced for a high fired ash (>800{d… more
Date: January 1, 1991
Creator: Meyer, M.L.
Partner: UNT Libraries Government Documents Department
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