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Radiolysis Process Model

Description: Assessing the performance of spent (used) nuclear fuel in geological repository requires quantification of time-dependent phenomena that may influence its behavior on a time-scale up to millions of years. A high-level waste repository environment will be a dynamic redox system because of the time-dependent generation of radiolytic oxidants and reductants and the corrosion of Fe-bearing canister materials. One major difference between used fuel and natural analogues, including unirradiated UO2, is the intense radiolytic field. The radiation emitted by used fuel can produce radiolysis products in the presence of water vapor or a thin-film of water (including OH• and H• radicals, O2-, eaq, H2O2, H2, and O2) that may increase the waste form degradation rate and change radionuclide behavior. H2O2 is the dominant oxidant for spent nuclear fuel in an O2 depleted water environment, the most sensitive parameters have been identified with respect to predictions of a radiolysis model under typical conditions. As compared with the full model with about 100 reactions it was found that only 30-40 of the reactions are required to determine [H2O2] to one part in 10–5 and to preserve most of the predictions for major species. This allows a systematic approach for model simplification and offers guidance in designing experiments for validation.
Date: July 17, 2012
Creator: Buck, Edgar C.; Wittman, Richard S.; Skomurski, Frances N.; Cantrell, Kirk J.; McNamara, Bruce K. & Soderquist, Chuck Z.
Partner: UNT Libraries Government Documents Department

Activated carbon testing for the 200 area effluent treatment facility

Description: This report documents pilot and laboratory scale testing of activated carbon for use in the 200 Area Effluent Treatment Facility peroxide decomposer columns. Recommendations are made concerning column operating conditions and hardware design, the optimum type of carbon for use in the plant, and possible further studies.
Date: January 17, 1997
Creator: Wagner, R.N.
Partner: UNT Libraries Government Documents Department

Hydrogen peroxide propulsion for smaller satellites (SSC98-VIII-1)

Description: As satellite designs shrink, providing maneuvering and control capability falls outside the realm of available propulsion technology. While cold gas has been used on the smallest satellites, hydrogen peroxide propellant is suggested as the next step in performance and cost before hydrazine. Minimal toxicity and a small scale enable benchtop propellant preparation and development testing. Progress toward low-cost thrusters and self-pressurizing tank systems is described.
Date: July 13, 1998
Creator: Whitehead, J. C.
Partner: UNT Libraries Government Documents Department

Investigation of the diborane - hydrogen peroxide propellant combination

Description: Report presenting the results of two runs made with liquid diborane and hydrogen peroxide in a small-scale rocket engine. The first run was very erratic and modifications were made to the testing apparatus and procedures for the second run. In the second run, the combustion started immediately and continued smoothly for 12 seconds of operation.
Date: May 28, 1948
Creator: Rowe, William H.; Ordin, Paul M. & Diehl, John M.
Partner: UNT Libraries Government Documents Department

On-Line Oxidation of Volatile Organic Compounds Generated by Sawmill Wood Kilns

Description: The primary purpose of this project was to evaluate the effectiveness of the use of hydrogen peroxide in combination with ultra-violet (UV) light for the reduction in the amount of volatile organic compounds (VOC’s) released into the environment during wood drying in sawmill kilns. As originally envisioned the scope of work included the optimization of reaction parameters i.e. pH, peroxide concentration, UV light intensity that would lead to successful destruction of VOC’s. The second phase involved development of a prototypical reactor that could be taken to a sawmill kiln for demonstration of treatment of a slipstream. However, after some of our initial experiments, we were forced to limit ourselves to more modest testing and development. During the project period we designed and constructed a small-scale reactor that was connected to the off-gas from a small wood drying kiln located at the Forest Products Lab at Mississippi State University. We ran a number of tests where we varied the process parameters (peroxide concentration, pH and UV light intensity) with no reasonable amount of VOC destruction. We employed a number of ways to atomize the peroxide into the kiln off-gas including using Laskin nozzles to see if that would improve the VOC reduction, but it was to no avail. The next option we explored was to try and utilize Fenton’s Reagent to see if that would be an effective tool in our treatment process. Initial measurements appeared to provide very good VOC reductions, but upon more detailed investigation it appeared that the oxygen being generated in the Fenton’s reaction was artificially reducing the VOC concentration coming from the treatment chamber. The last treatment system that we tried to use was the treatment of the kiln off-gas with hydrogen peroxide injection in the vapor phase. We were not able to achieve any success ...
Date: March 29, 2007
Creator: Kumar, R. Arun; Steele, Philip & Patterson, W. Dean
Partner: UNT Libraries Government Documents Department

Experimental Results for SimFuels

Description: Assessing the performance of Spent (or Used) Nuclear Fuel (UNF) in geological repository requires quantification of time-dependent phenomena that may influence its behavior on a time-scale up to millions of years. A high-level waste repository environment will be a dynamic redox system because of the time-dependent generation of radiolytic oxidants and reductants and the corrosion of Fe-bearing canister materials. One major difference between used fuel and natural analogues, including unirradiated UO2, is the intense radiolytic field. The radiation emitted by used fuel can produce radiolysis products in the presence of water vapor or a thin-film of water that may increase the waste form degradation rate and change radionuclide behavior. To study UNF, we have been working on producing synthetic UO2 ceramics, or SimFuels that can be used in testing and which will contain specific radionuclides or non-radioactive analogs so that we can test the impact of radiolysis on fuel corrosion without using actual spent fuel. Although, testing actual UNF would be ideal for understanding the long term behavior of UNF, it requires the use of hot cells and is extremely expensive. In this report, we discuss, factors influencing the preparation of SimFuels and the requirements for dopants to mimic the behavior of UNF. We have developed a reliable procedure for producing large grain UO2 at moderate temperatures. This process will be applied to a series of different formulations.
Date: August 22, 2012
Creator: Buck, Edgar C.; Casella, Andrew M.; Skomurski, Frances N.; MacFarlan, Paul J.; Soderquist, Chuck Z.; Wittman, Richard S. et al.
Partner: UNT Libraries Government Documents Department

OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER

Description: This project was an extension of previous research to improve the applicability of ozonation and will help address the petroleum-industry problem of treating produced water containing soluble organics. The goal of this project was to maximize oxidation of hexane-extractable organics during a single-pass operation. The project investigated: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Several types of methodologies for treatment of soluble organics in synthetic and actual produced waters have been performed. The technologies tested may be categorized as follows: (1) Destruction via sonochemical oxidation at different pH, salt concentration, ultraviolet irradiation, and ferrous iron concentrations. (2) Destruction via ozonation at different pH, salt concentration, hydrogen peroxide concentrations, ultraviolet irradiation, temperature, and reactor configurations.
Date: March 14, 2002
Creator: Klasson, KT
Partner: UNT Libraries Government Documents Department

Hydrogen from renewable resources monthly progress report

Description: During February, we achieved two significant results in our hydrogen storage activates. Reversible hydrogen uptake and release was measured at room temperature, near ambient pressure on the (IrClH{sub 2}(H{sub 2})Pr{sup i}{sub 3}) complex. Dr. Jensen also observed that certain polyhydzide complexes catalyze the low temperature, reversible dehydrogenation of cycloalkanes to aromatic hydrocarbons at temperatures as low as 130{degrees}C. This discovery may represent a breakthrough in chemical storage of hydrogen as all other cycloalkane dehydrogenation systems require temperatures in excess of 300{degrees}C.
Date: February 1, 1995
Creator: Rocheleau, R.E.
Partner: UNT Libraries Government Documents Department

Speciation of Fe in ambient aerosol and cloudwater

Description: Atmospheric iron (Fe) is thought to play an important role in cloudwater chemistry (e.g., S(IV) oxidation, oxidant production, etc.), and is also an important source of Fe to certain regions of the worlds oceans where Fe is believed to be a rate-limiting nutrient for primary productivity. This thesis focuses on understanding the chemistry, speciation and abundance of Fe in cloudwater and aerosol in the troposphere, through observations of Fe speciation in the cloudwater and aerosol samples collected over the continental United States and the Arabian Sea. Different chemical species of atmospheric Fe were measured in aerosol and cloudwater samples to help assess the role of Fe in cloudwater chemistry.
Date: August 15, 1996
Creator: Siefert, L.
Partner: UNT Libraries Government Documents Department

Self pressuring HTP feed systems

Description: Hydrogen peroxide tanks can be pressurized with decomposed HTP (high test hydrogen peroxide) originating in the tank itself. In rocketry, this offers the advantage of eliminating bulky and heavy inert gas storage. Several prototype self-pressurizing HTP systems have recently been designed and tested. Both a differential piston tank and a small gas-driven pump have been tried to obtain the pressure boost needed for flow through a gas generator and back to the tank. Results include terrestrial maneuvering tests of a prototype microsatellite, including warm gas attitude control jets.
Date: October 14, 1999
Creator: Whitehead, J.
Partner: UNT Libraries Government Documents Department

Atomic structure of active sites in O{sub 2} reduction on Au(111)/Tl{sub ad} electrodes in acid and alkaline solutions

Description: Surface x-ray scattering has been used to determine the structure of Tl adlayers on the Au(111) electrode surface during the course of 0{sub 2} reduction. 0. reduction is considerably catalyzed by Ti adlayers on Au(111). The half-wave potential is shifted to more positive values in the presence of the Ti adlayer. In both, acid and alkaline solutions TI causes a change in the reaction mechanism from a 2-ereduction to a 4e-reduction in a limited potential range. The in-plane X-ray diffraction measurements revealed that the close-packed rotated-hexagonal Ti phase, which exists in the potential range between -0.4V and the bulk TI deposition at {approx}{minus} 0.7V, has a lower activity for 0. reduction than the low-coverage phases in both solutions. It supports a 2e-reduction.0{sub 2} reduction does not change the TI coverage in this phase but causes a significant decrease of the in-plane diffracted intensity. The lower coverage phases which exist at more positive potentials, viz., aligned hexagonal in alkaline solution and patches of the (2 {times} 2)TI phase in acid solution, are conducive to a 4e-reduction. The diffraction intensity from these two phases, however, vanishes quickly during O{sub 2} reduction. It appears that the TI coverage remains on the surface unchanged. These observations indicate that the O{sub 2} molecules interact directly with the Tl adatoms prior to the charge transfer. This provides the most direct evidence that the outer sphere charge transfer mechanism in 0{sub 2} reduction is not operative for some surfaces. H{sub 2}0{sub 2} reduction is facile on the surface covered with the low-coverage TI phases, while it is almost completely suppressed by the rotated-hexagonal phase.
Date: December 31, 1995
Creator: Adzic, R.R. & Wang, J.X.
Partner: UNT Libraries Government Documents Department

Enhanced seed production under prolonged heat stress conditions in Arabidopsis thaliana plants deficient in cytosolic ascorbate peroxidase 2

Description: Article discussing enhanced seed production under prolonged heat stress conditions in Arabidopsis thaliana plants deficient in cytosolic ascorbate peroxidase 2.
Date: November 26, 2012
Creator: Suzuki, Nobuhiro; Miller, Gad; Sejima, Hiroe; Harper, Jeffrey F. & Mittler, Ron
Partner: UNT College of Arts and Sciences

Progress toward hydrogen peroxide micropulsion

Description: A new self-pressurizing propulsion system has liquid thrusters and gas jet attitude control without heavy gas storage vessels. A pump boosts the pressure of a small fraction of the hydrogen peroxide, so that reacted propellant can controllably pressurize its own source tank. The warm decomposition gas also powers the pump and is supplied to the attitude control jets. The system has been incorporated into a prototype microsatellite for terrestrial maneuvering tests. Additional progress includes preliminary testing of a bipropellant thruster, and storage of unstabilized hydrogen peroxide in small sealed tanks.
Date: July 8, 1999
Creator: Whitehead, J. C.; Dittman, M. D. & Ledebuhr, A. G.
Partner: UNT Libraries Government Documents Department

Perfluorinated quaternary ammonium salts of polyoxometalate anions: Fluorous biphasic oxidation catalysis with and without fluorous solvents

Description: Perfluorinated quaternary ammonium cations, [CF{sub 3}(CF{sub 2}){sub 7}(CH{sub 2}){sub 3}]{sub 3}CH{sub 3}N{sup +} (RFN{sup +}), were synthesized and used as counter cations for the [WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW{sub 9}O{sub 34}){sub 2}]{sup 12-} (M = Mn(II), Zn(II)), polyoxometalate. The (RFN{sup +}){sub 12}[WZnM{sub 2}(H{sub 2}O){sub 2}(ZnW9O{sub 34}){sub 2}] compounds were fluorous biphasic catalysts for alcohol and alkenol oxidation, and alkene epoxidation with aqueous hydrogen peroxide. Reaction protocols with or without a fluorous solvent were tested. The catalytic activity and selectivity was affected both by the hydrophobicity of the solvent and the substrate.
Date: May 28, 2003
Creator: Maayan, Galia; Fish, Richard H. & Neumann, Ronny
Partner: UNT Libraries Government Documents Department

Photolytic destruction of oxalate in aqueous mixed waste

Description: In aqueous plutonium processing, residual oxalic acid can be destroyed (oxalate kill) by UV light with hydrogen peroxide (H{sub 2}O{sub 2}) in 1 M HCl solutions. By controlling the amount of H{sub 2}O{sub 2}, the oxalate kill process will not affect the chloride concentration. In nitric acid solutions, UV light alone can destroy the oxalic acid. However, with H{sub 2}O{sub 2}, the rate of destruction is faster. After the destruction of oxalic acid, the acidic solutions may be reusable without further purification process.
Date: March 1, 1995
Creator: Wang, F.T. & Lum, B.Y.
Partner: UNT Libraries Government Documents Department

Development of chemiresponsive sensors for detection of common homemade explosives.

Description: Field-structured chemiresistors (FSCRs) are polymer based sensors that exhibit a resistance change when exposed to an analyte of interest. The amount of resistance change depends on the polymer-analyte affinity. The affinity can be manipulated by modifying the polymer within the FSCRs. In this paper, we investigate the ability of chemically modified FSCRs to sense hydrogen peroxide vapor. Five chemical species were chosen based on their hydrophobicity or reactivity with hydrogen peroxide. Of the five investigated, FSCRs modified with allyl methyl sulfide exhibited a significant response to hydrogen peroxide vapor. Additionally, these same FSCRs were evaluated against a common interferrant in hydrogen peroxide detection, water vapor. For the conditions investigated, the FSCRs modified with allyl methyl sulfide were able to successfully distinguish between water vapor and hydrogen peroxide vapor. A portion of the results presented here will be submitted to the Sensors and Actuators journal.
Date: May 1, 2012
Creator: Brotherton, Christopher M. & Wheeler, David Roger
Partner: UNT Libraries Government Documents Department

MINIMIZING DECOMPOSITION OF VAPORIZED HYDROGEN PEROXIDE IN CLEAN GALVANIZED STEEL DUCTING: IMPLICATIONS FOR BIOLOGICAL DECONTAMINATION

Description: This work examined the behavior of vaporous hydrogen peroxide (VHP) in clean, room-scale galvanized steel (GS) and polyvinylchloride-coated steel air ducts, to understand how it might be used to decontaminate larger ventilation systems. VHP injected into the GS duct decreased in concentration along the length of the duct, whereas VHP concentrations in the polyvinylchloride coated duct remained essentially constant, suggesting that VHP decomposed at the GS surface. However, decomposition was reduced at lower temperatures ({approx} 22 C) and higher flow rates ({approx} 80 actual cubic meter per hour). A computational fluid dynamics model incorporating reactive transport was used to estimate surface VHP concentrations where contamination is likely to reside, and also showed how bends encourage VHP decomposition. Use of G. stearothermophilus indicators, in conjunction with model estimates, indicated that a concentration-contact time of {approx} 100 mg/L H{sub 2}O{sub 2}(g){center_dot}min was required to achieve a 6 log reduction of indicator spores in clean GS duct, at 30 C. When VHP is selected for building decontamination, this work suggests the most efficacious strategy may be to decontaminate GS ducting separately from the rest of the building, as opposed to a single decontamination event in which the ventilation system is used to distribute VHP throughout the entire building.
Date: September 7, 2007
Creator: Verce, M F; Jayaraman, B; Ford, T D; Fisher, S E; Gadgil, A J & Carlsen, T M
Partner: UNT Libraries Government Documents Department

Decontamination Options for Drinking Water Contaminated with Bacillus anthracis Spores

Description: Five parameters were evaluated with surrogates of Bacillus anthracis spores to determine effective decontamination options for use in a contaminated drinking water supply. The parameters were: (1) type of Bacillus spore surrogate (B. thuringiensis or B. atrophaeus); (2) spore concentration in suspension (10{sup 2} to 10{sup 6} spores/ml); (3) chemical characteristics of decontaminant [sodium dicholor-s-triazinetrione dihydrate (Dichlor), hydrogen peroxide, potassium peroxymonosulfate (Oxone), sodium hypochlorite, and VirkonS{reg_sign}]; (4) decontaminant concentration (0.01% to 5%); and (5) decontaminant exposure time (10 min to 24 hr). Results from 162 suspension tests with appropriate controls are reported. Hydrogen peroxide at a concentration of 5%, and Dichlor and sodium hypochlorite at a concentration of 2%, were effective at spore inactivation regardless of spore type tested, spore exposure time, or spore concentration evaluated. This is the first reported study of Dichlor as an effective decontaminant for B. anthracis spore surrogates. Dichlor's desirable characteristics of high oxidation potential, high level of free chlorine, and more neutral pH than that of other oxidizers evaluated appear to make it an excellent alternative. All three oxidizers were effective against B. atrophaeus spores in meeting EPA's biocide standard of greater than a 6 log kill after a 10-minute exposure time and at lower concentrations than typically reported for biocide use. Solutions of 5% VirkonS{reg_sign} and Oxone were less effective decontaminants than other options evaluated in this study and did not meet the EPA's efficacy standard for biocides. Differences in methods and procedures reported by other investigators make quantitative comparisons among studies difficult.
Date: February 16, 2010
Creator: Raber, E & Burklund, A
Partner: UNT Libraries Government Documents Department

The corrosion of aluminum in dilute solutions: laboratory studies

Description: After it had been decided that aluminum was to be used as a corrosion-resistant material with good heat transfer properties, it was desired to determine the operating conditions to be used in the water-cooled Handford plant in order to avoid danger of corrosion penetration of thin aluminum parts. The studies here reported were undertaken with the object of determining these conditions by investigating the effects of all the known variables which might influence the corrosion behavior of aluminum in a water-coolded plant at HEW. The addition of hydrogen peroxide to the testing solutions was the only effort made to simulate special conditions at the plant.
Date: June 19, 1945
Creator: Draley, J.E.; Arendt, J.W.; English, G.C.; Story, E.F.; Wainscott, M.M. & Berger, R.W.
Partner: UNT Libraries Government Documents Department