Sample records for oxide conversion facility

  1. Dual-enhanced photothermal conversion properties of reduced graphene oxide-coated gold superparticles for light-triggered acoustic and thermal theranostics

    NASA Astrophysics Data System (ADS)

    Lin, Li-Sen; Yang, Xiangyu; Niu, Gang; Song, Jibin; Yang, Huang-Hao; Chen, Xiaoyuan

    2016-01-01

    A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the plasmonic coupling of the self-assembled gold nanoparticles and the interaction between GSPs and rGO endow rGO-GSPs with enhanced photothermal conversion properties, allowing rGO-GSPs to be used for sensitive photoacoustic detection and efficient photothermal ablation of tumours in vivo. This study provides a facile approach to prepare colloidal superparticles-graphene hybrid nanostructures and will pave the way toward the design and optimization of photothermal nanomaterials with improved properties for theranostic applications.A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the plasmonic coupling of the self-assembled gold nanoparticles and the interaction between GSPs and rGO endow rGO-GSPs with enhanced photothermal conversion properties, allowing rGO-GSPs to be used for sensitive photoacoustic detection and efficient photothermal ablation of tumours in vivo. This study provides a facile approach to prepare colloidal superparticles-graphene hybrid nanostructures and will pave the way toward the design and optimization of photothermal nanomaterials with improved properties for theranostic applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07552a

  2. Dual-enhanced photothermal conversion properties of reduced graphene oxide-coated gold superparticles for light-triggered acoustic and thermal theranostics†

    PubMed Central

    Lin, Li-Sen; Yang, Xiangyu; Niu, Gang

    2017-01-01

    A rational design of highly efficient photothermal agents that possess excellent light-to-heat conversion properties is a fascinating topic in nanotheranostics. Herein, we present a facile route to fabricate size-tunable reduced graphene oxide (rGO)-coated gold superparticles (rGO-GSPs) and demonstrate their dual-enhanced photothermal conversion properties for photoacoustic imaging and photothermal therapy. For the first time, graphene oxide (GO) was directly used as an emulsifying agent for the preparation of gold superparticles (GSPs) with near-infrared absorption by the emulsion method. Moreover, GO spontaneously deposited on the surface of GSPs could also act as the precursor of the rGO shell. Importantly, both the plasmonic coupling of the self-assembled gold nanoparticles and the interaction between GSPs and rGO endow rGO-GSPs with enhanced photothermal conversion properties, allowing rGO-GSPs to be used for sensitive photoacoustic detection and efficient photothermal ablation of tumours in vivo. This study provides a facile approach to prepare colloidal superparticles–graphene hybrid nanostructures and will pave the way toward the design and optimization of photothermal nanomaterials with improved properties for theranostic applications. PMID:26726809

  3. Uranium (III)-Plutonium (III) co-precipitation in molten chloride

    NASA Astrophysics Data System (ADS)

    Vigier, Jean-François; Laplace, Annabelle; Renard, Catherine; Miguirditchian, Manuel; Abraham, Francis

    2018-02-01

    Co-management of the actinides in an integrated closed fuel cycle by a pyrochemical process is studied at the laboratory scale in France in the CEA-ATALANTE facility. In this context the co-precipitation of U(III) and Pu(III) by wet argon sparging in LiCl-CaCl2 (30-70 mol%) molten salt at 705 °C is studied. Pu(III) is prepared in situ in the molten salt by carbochlorination of PuO2 and U(III) is then introduced as UCl3 after chlorine purge by argon to avoid any oxidation of uranium up to U(VI) by Cl2. The oxide conversion yield through wet argon sparging is quantitative. However, the preferential oxidation of U(III) in comparison to Pu(III) is responsible for a successive conversion of the two actinides, giving a mixture of UO2 and PuO2 oxides. Surprisingly, the conversion of sole Pu(III) in the same conditions leads to a mixture of PuO2 and PuOCl, characteristic of a partial oxidation of Pu(III) to Pu(IV). This is in contrast with coconversion of U(III)-Pu(III) mixtures but in agreement with the conversion of Ce(III).

  4. Room-temperature processed films of colloidal carved rod-shaped nanocrystals of reduced tungsten oxide as interlayers for perovskite solar cells.

    PubMed

    Masi, Sofia; Mastria, Rosanna; Scarfiello, Riccardo; Carallo, Sonia; Nobile, Concetta; Gambino, Salvatore; Sibillano, Teresa; Giannini, Cinzia; Colella, Silvia; Listorti, Andrea; Cozzoli, P Davide; Rizzo, Aurora

    2018-04-25

    Thanks to their high stability, good optoelectronic and extraordinary electrochromic properties, tungsten oxides are among the most valuable yet underexploited materials for energy conversion applications. Herein, colloidal one-dimensional carved nanocrystals of reduced tungsten trioxide (WO3-x) are successfully integrated, for the first time, as a hole-transporting layer (HTL) into CH3NH3PbI3 perovskite solar cells with a planar inverted device architecture. Importantly, the use of such preformed nanocrystals guarantees the facile solution-cast-only deposition of a homogeneous WO3-x thin film at room temperature, allowing achievement of the highest power conversion efficiency ever reported for perovskite solar cells incorporating raw and un-doped tungsten oxide based HTL.

  5. Lithography-free large-area metamaterials for stable thermophotovoltaic energy conversion

    DOE PAGES

    Coppens, Zachary J.; Kravchenko, Ivan I.; Valentine, Jason G.

    2016-02-08

    A large-area metamaterial thermal emitter is fabricated using facile, lithography-free techniques. The device is composed of conductive oxides, refractory ceramics, and noble metals and shows stable, selective emission after exposure to 1173 K for 22 h in oxidizing and inert atmospheres. Lastly, the results indicate that the metamaterial can be used to achieve high-performance thermophotovoltaic devices for applications such as portable power generation.

  6. Industrial Processes to Reduce Generation of Hazardous Waste at DoD Facilities. Phase 2 Report. Evaluation of 18 Case Studies.

    DTIC Science & Technology

    1985-07-15

    oxidize 13 .. . . . . . .- .. . ..-.-........ ~ -. trivalent chromium to hexavalent chromium and to selectively precipitate cation impurities from the...plating facilities. Chromium must be reduced to its trivalent state before it can be removed by precipitation as a hydroxide. Reduction is normally...conversion of hexavalent to trivalent chromium prior to precipitation. Trivalent solutions are typically less concentrated (22 g/L versus 150 g/L for

  7. Surface Science and the Advancement of Direct Olefin Epoxidation A Perspective on the Article, ‘‘Partial Oxidation of Higher Olefins on Ag(111) and Ag(110): Conversion of Styrene to Styrene Oxide, Benzene, and Benzoic Acid’’, by Andreas Klust and Robert J. Madix.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barteau, Mark A.

    2006-10-04

    The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. Few reactions are as conceptually simple or as devilishly difficult as the epoxidation of ethylene to form ethylene oxide:

  8. 7 CFR 1450.101 - Qualified biomass conversion facility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Qualified biomass conversion facility. 1450.101... (BCAP) Matching Payments § 1450.101 Qualified biomass conversion facility. (a) To be considered a qualified biomass conversion facility, a biomass conversion facility must enter into an agreement with CCC...

  9. Facile and Low-cost Synthesis of Mesoporous Ti-Mo Bi-metal Oxide Catalysts for Biodiesel Production from Esterification of Free Fatty Acids in Jatropha curcas Crude Oil.

    PubMed

    Zhang, Qiuyun; Li, Hu; Yang, Song

    2018-05-01

    Mesoporous Ti-Mo bi-metal oxides with various titanium-molybdenum ratios were successfully fabricated via a facile approach by using stearic acid as a low-cost template agent. thermal gravity (TG) /differential scanning calorimetry (DSC) analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nitrogen adsorption-desorption isotherm, NH 3 temperature-programmed desorption (NH 3 -TPD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements indicated these materials possessing mesoporous structure, sufficient pore size and high acid intensity. The catalytic performance of prepared catalysts was evaluated by esterification of free fatty acids in Jatropha curcas crude oil (JCCO) with methanol. The effects of various parameters on FFA conversion were investigated. The esterification conversion of 87.8% was achieved under the condition of 180°C, 2 h, methanol to JCCO molar ratio of 20:1 and 3.0 wt.% catalyst (relative to the weight of JCCO). The mesoporous catalysts were found to exhibit high activities toward the simultaneous esterification and transesterification of JCCO. Furthermore, the catalyst could be recovered with a good reusability.

  10. Nanoscale TiO2 and Fe2O3 Architectures for Solar Energy Conversion Schemes

    NASA Astrophysics Data System (ADS)

    Sedach, Pavel Anatolyvich

    The direct conversion of sunlight into more useable forms of energy has the potential of alleviating the environmental and social problems associated with a dependence on fossil fuels. If solar energy is to be utilized en-masse, however, it must be inexpensive and widely available. In this vein, the focus of this thesis is on nanostructured materials relevant to solar energy conversion and storage. Specifically, this thesis describes the ambient sol-gel synthesis of titanium dioxide (Ti02) nanowires designed for enhanced charge-transfer in solar collection devices, and the synthesis of novel disordered metal-oxide (MOx) catalysts for water oxidation. The introductory chapter of this thesis gives an overview of the various approaches to solar energy conversion. Sol---gel reaction conditions that enable the growth of one-dimensional (1-D) anatase TiO2 nanostructures from fluorine-doped tin oxide (FTO) for photovoltaics (PVs) are described in the second chapter. The generation of these linear nanostructures in the absence of an external bias or template is achieved by using facile experimental conditions (e.g., acetic acid (HOAc) and titanium isopropoxide (Ti(OiPr)4) in anhydrous heptane). The procedure was developed by functionalizing base-treated substrates with Ti-oxide nucleation sites that serve as a foundation for the growth of linear Ti-oxide macromolecules, which upon calcination, render uniform films of randomly oriented anatase TiO2 nanowires. A systematic evaluation of how reaction conditions (e.g., solvent volume, stoichiometry of reagents, substrate base treatment) affect the generation of these TiO 2 films is presented. A photo-organic MO. deposition route (i.e., photochemical metal-organic deposition (PMOD)) used to deposit thin-films of amorphous iron oxide (a-Fe2O3) for water oxidation catalysis is detailed in third chapter. It is shown that the irradiation of a spin-coated metal-organic film produces a film of non-crystalline a-Fe203. It is shown that annealing at various temperatures produces a-Fe 2O3 films with variable electronic properties and catalytic activities in the context of water oxidation. The study revealed that a-Fe2O3 are superior water oxidation catalysts (WOCs) relative to crystalline forms produced by high temperature annealing of the thin-films. This research has important implications in the conversion of sunlight into electricity, and then into hydrogen fuels.

  11. Facile integration of multiple magnetite nanoparticles for theranostics combining efficient MRI and thermal therapy

    NASA Astrophysics Data System (ADS)

    Huang, Guoming; Zhu, Xianglong; Li, Hui; Wang, Lirong; Chi, Xiaoqin; Chen, Jiahe; Wang, Xiaomin; Chen, Zhong; Gao, Jinhao

    2015-01-01

    Multifunctional nanostructures with both diagnostic and therapeutic capabilities have attracted considerable attention in biomedical research because they can offer great advantages in disease management and prognosis. In this work, a facile way to transfer the hydrophobic iron oxide (IO) nanoparticles into aqueous media by employing carboxylic graphene oxide (GO-COOH) as the transferring agent has been reported. In this one-step process, IO nanoparticles adhere to GO-COOH and form water-dispersible clusters via hydrophobic interactions between the hydrophobic ligands of IO nanoparticles and the basal plane of GO-COOH. The multiple IO nanoparticles on GO-COOH sheets (IO/GO-COOH) present a significant increase in T2 contrast enhancement. Moreover, the IO/GO-COOH nanoclusters also display a high photothermal conversion efficiency and can effectively inhibit tumor growth through the photothermal effects. It is envisioned that such IO/GO-COOH nanocomposites combining efficient MRI and photothermal therapy hold great promise in theranostic applications.Multifunctional nanostructures with both diagnostic and therapeutic capabilities have attracted considerable attention in biomedical research because they can offer great advantages in disease management and prognosis. In this work, a facile way to transfer the hydrophobic iron oxide (IO) nanoparticles into aqueous media by employing carboxylic graphene oxide (GO-COOH) as the transferring agent has been reported. In this one-step process, IO nanoparticles adhere to GO-COOH and form water-dispersible clusters via hydrophobic interactions between the hydrophobic ligands of IO nanoparticles and the basal plane of GO-COOH. The multiple IO nanoparticles on GO-COOH sheets (IO/GO-COOH) present a significant increase in T2 contrast enhancement. Moreover, the IO/GO-COOH nanoclusters also display a high photothermal conversion efficiency and can effectively inhibit tumor growth through the photothermal effects. It is envisioned that such IO/GO-COOH nanocomposites combining efficient MRI and photothermal therapy hold great promise in theranostic applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06616b

  12. Reversible chemical tuning of charge carriers for enhanced photoelectrochemical conversion and probing of living cells.

    PubMed

    Wang, Yongcheng; Tang, Jing; Zhou, Tong; Da, Peimei; Li, Jun; Kong, Biao; Yang, Zhongqin; Zheng, Gengfeng

    2014-12-10

    A facile, solution method for reversible tuning of oxygen vacancies inside TiO2 nanowires, in which the reducing treatment of TiO2 by NaBH4 leads to 2.4-fold increase of photocurrent density, compared to pristine TiO2 nanowires, is reported. Subsequent oxidizing treatment using KMnO4 or annealing in air can reset the photocurrent density to the original values. The incident photo-to-current conversion efficiency measurement exhibits that the reduced TiO2 nanowires present both enhanced photoactivity in both UV and visible regions. Density functional theory calculations reveal that the oxygen vacancies in the reduced TiO2 cause defect states in the band structure and result in enhanced carrier density and conductivity. In addition, the enhanced solar energy-driven photoelectrochemical conversion allows real-time, sensitive chemical probing of living cells that are directly grown on the TiO2 nanowire photoanodes. As proofs-of-concept, after functionalized with horseradish peroxidase (HRP) on the surface, the reduced TiO2 NWs demonstrate sensitive, real-time monitoring of the H2O2 levels in several distinctive living cell lines, with the lowest detectable H2O2 concentration of 7.7 nM. This reversible tuning of oxygen vacancies suggests a facile means for transition metal oxides, with enhanced photoconversion activity and electrochemical sensitivity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Low-temperature nitridation of manganese and iron oxides using NaNH2 molten salt.

    PubMed

    Miura, Akira; Takei, Takahiro; Kumada, Nobuhiro

    2013-10-21

    Manganese and iron nitrides are important functional materials, but their synthesis processes from oxides often require high temperatures. Herein, we show a novel meta-synthesis method for manganese and iron nitrides by low-temperature nitridation of their oxides using NaNH2 molten salt as the nitrogen source in an autoclave at 240 °C. With this method, nitridation of micrometer-sized oxide particles kept their initial morphologies, but the size of the primary particles decreased. The thermodynamic driving force is considered to be the conversion of oxides to sodium hydroxide, and the kinetic of nitridation is improved by the decrease of particle size and the low melting point of NaNH2. This technique as developed here has the advantages of low reaction temperature, reduced consumption of ammonia, employing nonspecialized equipment, and providing facile control of the reactions for producing nitrides from oxides.

  14. DUF6 Conversion Facility EISs

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  15. Fluxing template-assisted synthesis of sponge-like Fe2O3 microspheres toward efficient catalysis for CO oxidation

    NASA Astrophysics Data System (ADS)

    Li, Wenge; Hu, Yanjie; Jiang, Hao; Jiang, Yi; Wang, Yang; Huang, Su; Biswas, Pratim; Li, Chunzhong

    2018-06-01

    Constructing a porous architecture is a considerable strategy to enhance the catalytic activity of metal oxides catalysts for CO oxidation. In this work, we have developed porous sponge-like Fe2O3 microspheres by employing a facile aerosol spray pyrolysis. The NaNO3 salt in the spray solution plays a crucial role as a fluxing sacrifice template in the formation of the sponge-like structure, in which a high surface area of 216.2 m2 g-1 and an average pore size of 4 nm are obtained. This novel Fe2O3 catalyst exhibits an improved catalytic activity compared to usual iron oxides catalysts. Nearly 50% CO conversion at a relatively low temperature of 200 °C and 100% CO conversion at 300 °C at a space velocity of 60 000 ml h-1 g-1 are achieved. Furthermore, it displays an outstanding catalytic stability without distinct decay for 1000 min in a continuous stream at 300 °C. In addition to the effect of plentiful adsorption sites for the gas reactant, the promoted catalytic performance is also attributed to the function of abundant OH groups rooted in the large surface of the sponge-like structure, which induces faster reaction rate of CO oxidation via a bicarbonate route.

  16. Simple room-temperature preparation of high-yield large-area graphene oxide

    PubMed Central

    Huang, NM; Lim, HN; Chia, CH; Yarmo, MA; Muhamad, MR

    2011-01-01

    Graphene has attracted much attention from researchers due to its interesting mechanical, electrochemical, and electronic properties. It has many potential applications such as polymer filler, sensor, energy conversion, and energy storage devices. Graphene-based nanocomposites are under an intense spotlight amongst researchers. A large amount of graphene is required for preparation of such samples. Lately, graphene-based materials have been the target for fundamental life science investigations. Despite graphene being a much sought-after raw material, the drawbacks in the preparation of graphene are that it is a challenge amongst researchers to produce this material in a scalable quantity and that there is a concern about its safety. Thus, a simple and efficient method for the preparation of graphene oxide (GO) is greatly desired to address these problems. In this work, one-pot chemical oxidation of graphite was carried out at room temperature for the preparation of large-area GO with ~100% conversion. This high-conversion preparation of large-area GO was achieved using a simplified Hummer’s method from large graphite flakes (an average flake size of 500 μm). It was found that a high degree of oxidation of graphite could be realized by stirring graphite in a mixture of acids and potassium permanganate, resulting in GO with large lateral dimension and area, which could reach up to 120 μm and ~8000 μm2, respectively. The simplified Hummer’s method provides a facile approach for the preparation of large-area GO. PMID:22267928

  17. Catalytic evaluation on liquid phase oxidation of vanillyl alcohol using air and H2O2 over mesoporous Cu-Ti composite oxide

    NASA Astrophysics Data System (ADS)

    Saha, Subrata; Hamid, Sharifah Bee Abd; Ali, Tammar Hussein

    2017-02-01

    A mesoporous, highly crystalline Cu-Ti composite oxide catalyst was prepared via facile, simple and modified solution method varying Cu and Ti ratio for selective liquid phase oxidation of vanillyl alcohol. Various spectroscopic procedures were employed to systematically characterize the catalyst structural and physicochemical properties. The defect chemistry of the catalyst was confirmed from the presence of surface defects revealed through HRTEM imagery between the TiO2 (101) and Cu3TiO4 (012) planes, complemented by the XRD profiling. Further, presence of oxygen vacancy evidenced by O 1s XPS spectra were observed on the catalyst surface. Moreover, the stoichiometry of Cu and Ti in the catalyst synthesis protocol was notably found to be the vital determinant to alter the redox properties of Cu-Ti composite oxide catalyst supported by H2-TPR. O2-TPD analysis. Moreover, a rational investigation was done using different oxidants such as air and H2O2 with variables reaction conditions. The catalyst was active for liquid phase oxidation of vanillyl alcohol to vanillin with performance of 66% conversion and 71% selectivity using H2O2 in base free condition. And also, catalytic activity was significantly improved by 94% conversion with 86% selectivity to vanillin in liquid phase aerobic oxidation at the optimum reaction conditions. To expand the superiority of the catalyst, three times reusability study was also examined with appreciable catalytic activity.

  18. Oligomeric flavanoids. Part 15a. Base-catalyzed pyran rearrangements of procyanidin B-2, and evidence for the oxidative transformation of B- to A-type procyanidins

    Treesearch

    Johann F.W. Burger; Herbert Kolodziej; Richard W. Hemingway; Jan P. Steynberg; Desmond A. Young; Daneel Ferreira

    1990-01-01

    Procyanidin B-2 3 is subject to facile C-ring isomerizations in 0.1M NaHCO3 solution to form a novel series of 3,4,9,1o-tetrahydro-2H,8H-pyrano[2,3-h]chromenes 7, 9, and 10. The low percentage conversion of B- to A-...

  19. Defense Waste Processing Facility Nitric- Glycolic Flowsheet Chemical Process Cell Chemistry: Part 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zamecnik, J.; Edwards, T.

    The conversions of nitrite to nitrate, the destruction of glycolate, and the conversion of glycolate to formate and oxalate were modeled for the Nitric-Glycolic flowsheet using data from Chemical Process Cell (CPC) simulant runs conducted by Savannah River National Laboratory (SRNL) from 2011 to 2016. The goal of this work was to develop empirical correlation models to predict these values from measureable variables from the chemical process so that these quantities could be predicted a-priori from the sludge or simulant composition and measurable processing variables. The need for these predictions arises from the need to predict the REDuction/OXidation (REDOX) statemore » of the glass from the Defense Waste Processing Facility (DWPF) melter. This report summarizes the work on these correlations based on the aforementioned data. Previous work on these correlations was documented in a technical report covering data from 2011-2015. This current report supersedes this previous report. Further refinement of the models as additional data are collected is recommended.« less

  20. Concentrations and patterns of perfluoroalkyl and polyfluoroalkyl substances in a river and three drinking water treatment plants near and far from a major production source.

    PubMed

    Boiteux, Virginie; Dauchy, Xavier; Bach, Cristina; Colin, Adeline; Hemard, Jessica; Sagres, Véronique; Rosin, Christophe; Munoz, Jean-François

    2017-04-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are emerging contaminants that have been detected in the environment, biota and humans. Drinking water is a route of exposure for populations using water contaminated by PFAS discharges. This research entailed measuring concentrations, mass flows and investigating the fate of dozens PFASs in a river receiving effluents from a fluorochemical manufacturing facility. To measure the total concentration of perfluoroalkyl carboxylic acid (PFCA) precursors, an oxidative conversion method was used. Several dozen samples were collected in the river (water and sediment), in drinking water resources and at different treatment steps on four sampling dates. One PFCA and three fluorotelomers (FTs) were detected up to 62km downstream from the manufacturing facility. 6:2 Fluorotelomer sulfonamide alkylbetaine (6:2 FTAB) was the predominant PFAS with a mass flow of 3830g/day 5.2km downstream from the facility. At all sampling points, PFAS concentrations in sediment were quite low (<6ng/g dw). Five of the 11 investigated wells showed detectable concentrations of PFASs. Interestingly, their profile patterns were different from those observed in the river, suggesting a transformation of PFCA precursors in the sediments of alluvial groundwater. Conventional drinking water treatments (aeration, sand or granular activated carbon filtration, ozonation or chlorination) did not efficiently remove PFASs. Furthermore, an increase in concentration of certain PFASs was observed after ozonation, suggesting that some FTs such as 6:2 FTAB can break down. Only nanofiltration was able to remove all the analyzed PFASs. In the treated water, total PFAS concentrations never exceeded 60ng/L. The oxidative conversion method revealed the presence of unidentified PFCA precursors in the river. Therefore, 18 to 77% of the total PFCA content after oxidation consisted of unidentified chemical species. In the treated water, these percentages ranged from 0 to 29%, relatively and reassuringly low values. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. A Low-Temperature, Solution-Processable, Cu-Doped Nickel Oxide Hole-Transporting Layer via the Combustion Method for High-Performance Thin-Film Perovskite Solar Cells

    DOE PAGES

    Jung, Jae Woong; Chueh, Chu-Chen; Jen, Alex K. -Y.

    2015-10-20

    The promising photophysical properties of the emerging organometallic halide perovskites, such as intense broadband absorption, high charge carrier mobility, and long charge diffusion length, have enabled the rapid development in solar cells reaching over 20% power conversion effi ciency (PCE) recently. Especially, the low material cost and facile solution processability of perovskites are very attractive as next-generation photovoltaic materials for sustainable energy.

  2. A Ni(iii) complex stabilized by silica nanoparticles as an efficient nanoheterogeneous catalyst for oxidative C-H fluoroalkylation.

    PubMed

    Khrizanforov, Mikhail N; Fedorenko, Svetlana V; Strekalova, Sofia O; Kholin, Kirill V; Mustafina, Asiya R; Zhilkin, Mikhail Ye; Khrizanforova, Vera V; Osin, Yuri N; Salnikov, Vadim V; Gryaznova, Tatyana V; Budnikova, Yulia H

    2016-07-26

    We have developed Ni(III)-doped silica nanoparticles ([(bpy)xNi(III)]@SiO2) as a recyclable, low-leaching, and efficient oxidative functionalization nanocatalyst for aromatic C-H bonds. The catalyst is obtained by doping the complex [(bpy)3Ni(II)] on silica nanoparticles along with its subsequent electrooxidation to [(bpy)xNi(III)] without an additional oxidant. The coupling reaction of arenes with perfluoroheptanoic acid occurs with 100% conversion of reactants in a single step at room temperature under nanoheterogeneous conditions. The catalyst content is only 1% with respect to the substrates under electrochemical regeneration conditions. The catalyst can be easily separated from the reaction mixture and reused a minimum of five times. The results emphasize immobilization on the silica support and the electrochemical regeneration of Ni(III) complexes as a facile route for developing an efficient nanocatalyst for oxidative functionalization.

  3. Public Involvement Opportunities for the DUF6 Conversion Facility EISs

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  4. 7 CFR 1450.101 - Qualified biomass conversion facility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Qualified biomass conversion facility. 1450.101... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments § 1450.101 Qualified biomass conversion facility. (a) To be considered a...

  5. 7 CFR 1450.101 - Qualified biomass conversion facility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Qualified biomass conversion facility. 1450.101... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments § 1450.101 Qualified biomass conversion facility. (a) To be considered a...

  6. 7 CFR 1450.101 - Qualified biomass conversion facility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Qualified biomass conversion facility. 1450.101... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments § 1450.101 Qualified biomass conversion facility. (a) To be considered a...

  7. Facile synthesis of uniform MoO2/Mo2CTx heteromicrospheres as high-performance anode materials for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Min, Jie; Wang, Kangyan; Liu, Jun; Yao, Yang; Wang, Wenjun; Yang, Linyu; Zhang, Ruizhi; Lei, Ming

    2017-09-01

    Uniform nano/micro-spherical MoO2/Mo2CTx (T = O) heterostructures have been synthesized through a heterocatalytic reaction with subsequent facile calcinations. Given the high activity of HxMoO3/C precursors, this strategy opens a low-temperature route to realize the fabrication of nanocrystalline MoO2/Mo2CTx heterostructures, leading to achieve rapidly activated conversion reaction and extrinsic pseudocapacitive behaviour. Rather than carbon, highly conductive Mo2CTx decreases the charge transfer resistance in MoO2 and maintains its structural stability upon lithiation/delithiation, ensuring the heterostructures with excellent cyclability (e.g., up to 833 mA h g-1 at 100 mA g-1 for 160 cycles with 95% capacity retention) and high rate capability (e.g., 665 mA h g-1 at 1 A g-1). Additionally, owing to the carbon-free characteristic, the secondary nano/microstructure feature and the suppressed surface oxidation trait, MoO2/Mo2CTx heterostructures, therefore, can deliver an improved initial Coulombic efficiency (e.g., up to 78% at 100 mA g-1). The present oxycarbide transformation and hybridization strategies are facile but effective, and they are very promising to be applied to converting other oxides-carbon composites into oxides/carbides heterostructures towards achieving higher electrochemical performance.

  8. Public Involvement Opportunities for the DUF6 Conversion Facility EISs

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  9. Facile fabrication of nanofluidic diode membranes using anodic aluminium oxide.

    PubMed

    Wu, Songmei; Wildhaber, Fabien; Vazquez-Mena, Oscar; Bertsch, Arnaud; Brugger, Juergen; Renaud, Philippe

    2012-09-21

    Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al(2)O(3)/SiO(2) (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al(2)O(3) (positive) and SiO(2) (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion.

  10. Oxidation and sensing of ascorbic acid and dopamine on self-assembled gold nanoparticles incorporated within polyaniline film

    NASA Astrophysics Data System (ADS)

    Chu, Wenya; Zhou, Qun; Li, Shuangshuang; Zhao, Wei; Li, Na; Zheng, Junwei

    2015-10-01

    Electrochemical biosensors based on conducting polymers incorporated with metallic nanoparticles can greatly enhance sensitivity and selectivity. Herein, we report a facile fabrication approach for polyaniline (PAN) incorporated with a gold nanoparticle (AuNP) composite electrode by electrodeposition of PAN on a self-assembled AuNP layer on the surface of an indium tin oxide electrode. The resulting AuNP/PAN composite electrode exhibits a remarkable synergistic effect on the electrocatalytic oxidation of ascorbic acid (AA) and dopamine (DA). It is demonstrated that the oxidation reaction of AA mainly occurs at AuNPs inside the PAN film as the ascorbate anions are doped into the polymer during the oxidation of the PAN film. Conversely, the oxidation of positively charged DA may only take place at the PAN/solution interface. The different mechanisms of the electrode reactions result in the oxidation of AA and DA occurring at different potentials. As a result, the AuNP/PAN composite electrode can be employed to simultaneously detect AA and DA with a good linear range, high sensitivity, and low detection limit.

  11. Nano Copper Oxide-Modified Carbon Cloth as Cathode for a Two-Chamber Microbial Fuel Cell

    PubMed Central

    Dong, Feng; Zhang, Peng; Li, Kexun; Liu, Xianhua; Zhang, Pingping

    2016-01-01

    In this work, Cu2O nanoparticles were deposited on a carbon cloth cathode using a facile electrochemical method. The morphology of the modified cathode, which was characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) tests, showed that the porosity and specific surface area of the cathode improved with longer deposition times. X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV) results showed that cupric oxide and cuprous oxide coexisted on the carbon cloth, which improved the electrochemical activity of cathode. The cathode with a deposition time of 100 s showed the best performance, with a power density twice that of bare carbon cloth. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) results revealed that moderate deposition of nano copper oxide on carbon cloth could dramatically reduce the charge transfer resistance, which contributed to the enhanced electrochemical performance. The mediation mechanism of copper oxide nanocatalyst was illustrated by the fact that the recycled conversion between cupric oxide and cuprous oxide accelerated the electron transfer efficiency on the cathode. PMID:28335366

  12. Nano Copper Oxide-Modified Carbon Cloth as Cathode for a Two-Chamber Microbial Fuel Cell.

    PubMed

    Dong, Feng; Zhang, Peng; Li, Kexun; Liu, Xianhua; Zhang, Pingping

    2016-12-09

    In this work, Cu₂O nanoparticles were deposited on a carbon cloth cathode using a facile electrochemical method. The morphology of the modified cathode, which was characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) tests, showed that the porosity and specific surface area of the cathode improved with longer deposition times. X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV) results showed that cupric oxide and cuprous oxide coexisted on the carbon cloth, which improved the electrochemical activity of cathode. The cathode with a deposition time of 100 s showed the best performance, with a power density twice that of bare carbon cloth. Linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) results revealed that moderate deposition of nano copper oxide on carbon cloth could dramatically reduce the charge transfer resistance, which contributed to the enhanced electrochemical performance. The mediation mechanism of copper oxide nanocatalyst was illustrated by the fact that the recycled conversion between cupric oxide and cuprous oxide accelerated the electron transfer efficiency on the cathode.

  13. Simultaneous constraint and phase conversion processing of oxide superconductors

    DOEpatents

    Li, Qi; Thompson, Elliott D.; Riley, Jr., Gilbert N.; Hellstrom, Eric E.; Larbalestier, David C.; DeMoranville, Kenneth L.; Parrell, Jeffrey A.; Reeves, Jodi L.

    2003-04-29

    A method of making an oxide superconductor article includes subjecting an oxide superconductor precursor to a texturing operation to orient grains of the oxide superconductor precursor to obtain a highly textured precursor; and converting the textured oxide superconducting precursor into an oxide superconductor, while simultaneously applying a force to the precursor which at least matches the expansion force experienced by the precursor during phase conversion to the oxide superconductor. The density and the degree of texture of the oxide superconductor precursor are retained during phase conversion. The constraining force may be applied isostatically.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zamecnik, J. R.; Edwards, T. B.

    The conversions of nitrite to nitrate, the destruction of glycolate, and the conversion of glycolate to formate and oxalate were modeled for the Nitric-Glycolic flowsheet using data from Chemical Process Cell (CPC) simulant runs conducted by SRNL from 2011 to 2015. The goal of this work was to develop empirical correlations for these variables versus measureable variables from the chemical process so that these quantities could be predicted a-priori from the sludge composition and measurable processing variables. The need for these predictions arises from the need to predict the REDuction/OXidation (REDOX) state of the glass from the Defense Waste Processingmore » Facility (DWPF) melter. This report summarizes the initial work on these correlations based on the aforementioned data. Further refinement of the models as additional data is collected is recommended.« less

  15. Bulk heterojunction perovskite solar cells based on room temperature deposited hole-blocking layer: Suppressed hysteresis and flexible photovoltaic application

    NASA Astrophysics Data System (ADS)

    Chen, Zhiliang; Yang, Guang; Zheng, Xiaolu; Lei, Hongwei; Chen, Cong; Ma, Junjie; Wang, Hao; Fang, Guojia

    2017-05-01

    Perovskite solar cells have developed rapidly in recent years as the third generation solar cells. In spite of the great improvement achieved, there still exist some issues such as undesired hysteresis and indispensable high temperature process. In this work, bulk heterojunction perovskite-phenyl-C61-butyric acid methyl ester solar cells have been prepared to diminish hysteresis using a facile two step spin-coating method. Furthermore, high quality tin oxide films are fabricated using pulse laser deposition technique at room temperature without any annealing procedure. The as fabricated tin oxide film is successfully applied in bulk heterojunction perovskite solar cells as a hole blocking layer. Bulk heterojunction devices based on room temperature tin oxide exhibit almost hysteresis-free characteristics with power conversion efficiency of 17.29% and 14.0% on rigid and flexible substrates, respectively.

  16. Facile solid-state synthesis of oxidation-resistant metal nanoparticles at ambient conditions

    NASA Astrophysics Data System (ADS)

    Lee, Kyu Hyung; Jung, Hyuk Joon; Lee, Ju Hee; Kim, Kyungtae; Lee, Byeongno; Nam, Dohyun; Kim, Chung Man; Jung, Myung-Hwa; Hur, Nam Hwi

    2018-05-01

    A simple and scalable method for the synthesis of metal nanoparticles in the solid-state was developed, which can produce nanoparticles in the absence of solvents. Nanoparticles of coinage metals were synthesized by grinding solid hydrazine and the metal precursors in their acetates and oxides at 25 °C. The silver and gold acetates converted completely within 6 min into Ag and Au nanoparticles, respectively, while complete conversion of the copper acetate to the Cu sub-micrometer particles took about 2 h. Metal oxide precursors were also converted into metal nanoparticles by grinding alone. The resulting particles exhibit distinctive crystalline lattice fringes, indicating the formation of highly crystalline phases. The Cu sub-micrometer particles are better resistant to oxidation and exhibit higher conductivity compared to conventional Cu nanoparticles. This solid-state method was also applied for the synthesis of platinum group metals and intermetallic Cu3Au, which can be further extended to synthesize other metal nanoparticles.

  17. LITERATURE REVIEW FOR OXALATE OXIDATION PROCESSES AND PLUTONIUM OXALATE SOLUBILITY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nash, C.

    2012-02-03

    A literature review of oxalate oxidation processes finds that manganese(II)-catalyzed nitric acid oxidation of oxalate in precipitate filtrate is a viable and well-documented process. The process has been operated on the large scale at Savannah River in the past, including oxidation of 20 tons of oxalic acid in F-Canyon. Research data under a variety of conditions show the process to be robust. This process is recommended for oxalate destruction in H-Canyon in the upcoming program to produce feed for the MOX facility. Prevention of plutonium oxalate precipitation in filtrate can be achieved by concentrated nitric acid/ferric nitrate sequestration of oxalate.more » Organic complexants do not appear practical to sequester plutonium. Testing is proposed to confirm the literature and calculation findings of this review at projected operating conditions for the upcoming campaign. H Canyon plans to commence conversion of plutonium metal to low-fired plutonium oxide in 2012 for eventual use in the Mixed Oxide Fuel (MOX) Facility. The flowsheet includes sequential operations of metal dissolution, ion exchange, elution, oxalate precipitation, filtration, and calcination. All processes beyond dissolution will occur in HB-Line. The filtration step produces an aqueous filtrate that may have as much as 4 M nitric acid and 0.15 M oxalate. The oxalate needs to be removed from the stream to prevent possible downstream precipitation of residual plutonium when the solution is processed in H Canyon. In addition, sending the oxalate to the waste tank farm is undesirable. This report addresses the processing options for destroying the oxalate in existing H Canyon equipment.« less

  18. Enhancement of the inverted polymer solar cells via ZnO doped with CTAB

    NASA Astrophysics Data System (ADS)

    Sivashnamugan, Kundan; Guo, Tzung-Fang; Hsu, Yao-Jane; Wen, Ten-Chin

    2018-02-01

    A facile approach enhancing electron extraction in zinc oxide (ZnO) electron transfer interlayer and improving performance of bulk-heterojunction (BHJ) polymer solar cells (PSCs) by adding cetyltrimethylammonium bromide (CTAB) into sol-gel ZnO precursor solution was demonstrated in this work. The power conversion efficiency (PCE) has a 24.1% increment after modification. Our results show that CTAB can dramatically influence optical, electrical and morphological properties of ZnO electron transfer layer, and work as effective additive to enhance the performance of bulk- heterojunction polymer solar cells.

  19. CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, OCTOBER, NOVEMBER, DECEMBER 1960

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1961-03-01

    Chemical-metallurgical processing studies were made of pyrometallurgical development snd research, and fuel processing facilities for EBR-II. Fuel-cycle applications of fluidization and volatility techniques included laboratory investigations of fluoride volatility processes, engineeringscale development, and conversion of UF/sub 6/ to UO/sub 2/. Reactor safety studies consisted of metal oxidation and ignition kinetics, and metal-water reactions. Reactor chemistry investigations were conducted to determine nuclear constants and suitable reactor decontamination methods. Routine operations are summarized for the high-level gammairradiation facillty and waste processing. (B.O.G.)

  20. Photochemical Hydrogen Doping Induced Embedded Two-Dimensional Metallic Channel Formation in InGaZnO at Room Temperature.

    PubMed

    Kim, Myeong-Ho; Lee, Young-Ahn; Kim, Jinseo; Park, Jucheol; Ahn, Seungbae; Jeon, Ki-Joon; Kim, Jeong Won; Choi, Duck-Kyun; Seo, Hyungtak

    2015-10-27

    The photochemical tunability of the charge-transport mechanism in metal-oxide semiconductors is of great interest since it may offer a facile but effective semiconductor-to-metal transition, which results from photochemically modified electronic structures for various oxide-based device applications. This might provide a feasible hydrogen (H)-radical doping to realize the effectively H-doped metal oxides, which has not been achieved by thermal and ion-implantation technique in a reliable and controllable way. In this study, we report a photochemical conversion of InGaZnO (IGZO) semiconductor to a transparent conductor via hydrogen doping to the local nanocrystallites formed at the IGZO/glass interface at room temperature. In contrast to thermal or ionic hydrogen doping, ultraviolet exposure of the IGZO surface promotes a photochemical reaction with H radical incorporation to surface metal-OH layer formation and bulk H-doping which acts as a tunable and stable highly doped n-type doping channel and turns IGZO to a transparent conductor. This results in the total conversion of carrier conduction property to the level of metallic conduction with sheet resistance of ∼16 Ω/□, room temperature Hall mobility of 11.8 cm(2) V(-1) sec(-1), the carrier concentration at ∼10(20) cm(-3) without any loss of optical transparency. We demonstrated successful applications of photochemically highly n-doped metal oxide via optical dose control to transparent conductor with excellent chemical and optical doping stability.

  1. Monodispersed porous flowerlike PtAu nanocrystals as effective electrocatalysts for ethanol oxidation

    NASA Astrophysics Data System (ADS)

    Li, Shumin; Xu, Hui; Xiong, Zhiping; Zhang, Ke; Wang, Caiqin; Yan, Bo; Guo, Jun; Du, Yukou

    2017-11-01

    Designing and tuning the bimetallic nanoparticles with desirable morphology and structure can embody them with greatly enhanced electrocatalytic activity and stability towards liquid fuel oxidation. We herein reported a facile one-pot method for the controlled synthesis of monodispersed binary PtAu nanoflowers with abundant exposed surface area. Owing to its fantastic structure, synergistic and electronic effect, such as-prepared PtAu nanoflowers exhibited outstandingly high electrocatalytic activity with the mass activity of 6482 mA mg-1 towards ethanol oxidation, which is 28.3 times higher than that of commercial Pt/C (227 mA mg-1). More interesting, the present PtAu nanoflower catalysts are more stable for the ethanol oxidation reaction in the alkaline with lower current density decay and retained a much higher current density after successive CVs of 500 cycles than that of commercial Pt/C. This work may open a new way for maximizing the catalytic performance of electrocatalysts towards ethanol oxidation by synthesizing shape-controlled alloy nanoparticles with more surface active sites to enhance the performances of direct fuel cells reaction, chemical conversion, and beyond.

  2. A facile fabrication of chemically converted graphene oxide thin films and their uses as absorber materials for solar cells

    NASA Astrophysics Data System (ADS)

    Adelifard, Mehdi; Darudi, Hosein

    2016-07-01

    There is a great interest in the use of graphene sheets in thin film solar cells with low-cost and good-optoelectronic properties. Here, the production of absorbent conductive reduced graphene oxide (RGO) thin films was investigated. RGO thin films were prepared from spray-coated graphene oxide (GO) layers at various substrate temperature followed by a simple hydrazine-reducing method. The structural, morphological, optical, and electrical characterizations of graphene oxide (GO) and RGO thin films were investigated. X-ray diffraction analysis showed a phase shift from GO to RGO due to hydrazine treatment, in agreement with the FTIR spectra of the layers. FESEM images clearly exhibited continuous films resulting from the overlap of graphene nanosheets. The produced low-cost thin films had high absorption coefficient up to 1.0 × 105 cm-1, electrical resistance as low as 0.9 kΩ/sq, and effective optical band gap of about 1.50 eV, close to the optimum value for solar conversion. The conductive absorbent properties of the reduced graphene oxide thin films would be useful to develop photovoltaic cells.

  3. A facile approach to prepare crumpled CoTMPyP/electrochemically reduced graphene oxide nanohybrid as an efficient electrocatalyst for hydrogen evolution reaction

    NASA Astrophysics Data System (ADS)

    Ma, Juanjuan; Liu, Lin; Chen, Qian; Yang, Min; Wang, Danping; Tong, Zhiwei; Chen, Zhong

    2017-03-01

    Elaborate design and synthesis of efficient and stable non-Pt electrocatalysts for some renewable energy related conversion/storage processes are one of the major goals of sustainable chemistry. Herein, we report a facile method to fabricate Co porphyrin functionalized electrochemically reduced graphene oxide (CoTMPyP/ERGO) thin film by direct assembly of oppositely charged tetrakis(N-methylpyridyl) porphyrinato cobalt (CoTMPyP) and GO nanosheets under mild conditions followed by an electrochemical reduction procedure. STEM analysis confirms that CoTMPyP nanoaggregates are homogeneously distributed over the graphene surface. The electrochemical properties of CoTMPyP/ERGO were investigated by cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy. The results demonstrate that CoTMPyP/ERGO nanohybrid film can serve as excellent electrocatalyst for hydrogen evolution in alkaline solution with high activity and stability. The intimate contact and efficient electron transfer between CoTMPyP and ERGO, as well as the crumpled structure, contribute to the improvement of the electrocatalytic performance.

  4. Ownership conversions and nursing home performance.

    PubMed

    Grabowski, David C; Stevenson, David G

    2008-08-01

    To examine the effects of ownership conversions on nursing home performance. Online Survey, Certification, and Reporting system data from 1993 to 2004, and the Minimum Data Set (MDS) facility reports from 1998 to 2004. Regression specification incorporating facility fixed effects, with terms to identify trends in the pre- and postconversion periods. The annual rate of nursing home conversions almost tripled between 1994 and 2004. Our regression results indicate converting facilities are generally different throughout the pre/postconversion years, suggesting little causal effect of ownership conversions on nursing home performance. Before and after conversion, nursing homes converting from nonprofit to for-profit status generally exhibit deterioration in their performance, while nursing homes converting from for-profit to nonprofit status generally exhibit improvement. Policy makers have expressed concern regarding the implications of ownership conversions for nursing home performance. Our results imply that regulators and policy makers should not only monitor the outcomes of nursing home conversions, but also the targets of these conversions.

  5. Comparison of x ray computed tomography number to proton relative linear stopping power conversion functions using a standard phantom.

    PubMed

    Moyers, M F

    2014-06-01

    Adequate evaluation of the results from multi-institutional trials involving light ion beam treatments requires consideration of the planning margins applied to both targets and organs at risk. A major uncertainty that affects the size of these margins is the conversion of x ray computed tomography numbers (XCTNs) to relative linear stopping powers (RLSPs). Various facilities engaged in multi-institutional clinical trials involving proton beams have been applying significantly different margins in their patient planning. This study was performed to determine the variance in the conversion functions used at proton facilities in the U.S.A. wishing to participate in National Cancer Institute sponsored clinical trials. A simplified method of determining the conversion function was developed using a standard phantom containing only water and aluminum. The new method was based on the premise that all scanners have their XCTNs for air and water calibrated daily to constant values but that the XCTNs for high density/high atomic number materials are variable with different scanning conditions. The standard phantom was taken to 10 different proton facilities and scanned with the local protocols resulting in 14 derived conversion functions which were compared to the conversion functions used at the local facilities. For tissues within ±300 XCTN of water, all facility functions produced converted RLSP values within ±6% of the values produced by the standard function and within 8% of the values from any other facility's function. For XCTNs corresponding to lung tissue, converted RLSP values differed by as great as ±8% from the standard and up to 16% from the values of other facilities. For XCTNs corresponding to low-density immobilization foam, the maximum to minimum values differed by as much as 40%. The new method greatly simplifies determination of the conversion function, reduces ambiguity, and in the future could promote standardization between facilities. Although it was not possible from these experiments to determine which conversion function is most appropriate, the variation between facilities suggests that the margins used in some facilities to account for the uncertainty in converting XCTNs to RLSPs may be too small.

  6. ZIF-67-derived hollow nanocages with layered double oxides shell as high-Efficiency catalysts for CO oxidation

    NASA Astrophysics Data System (ADS)

    Kong, Wenpeng; Li, Jing; Chen, Yao; Ren, Yuqing; Guo, Yonghua; Niu, Shengli; Yang, Yanzhao

    2018-04-01

    Constructing non-precious hybrid metal oxides with specific morphology as cost-effective and highly efficient catalysts is a promising way for the automotive exhaust purification. In this work, we report a facile strategy for the fabrication of a unique hollow Co-Ni layered double oxides (HLDO) nanocages by using zeolitic imidazole frameworks (ZIFs) as template. The synthesis of intermediate core-shell and hollow Co-Ni layered double hydroxides (HLDH) nanoflakes as well as the corresponding Co-Ni oxides products were successfully controlled, and the formation process was also explained. Among ZIF-67-derived oxides, HLDO exhibits excellent catalytic activities (complete conversion of CO into CO2 at 118 °C) and long-term stability for CO oxidation. The remarkable catalytic activities of HLDO can be attributed to high surface area (258 m2 g-1) inherited from the HLDH, which could provide more active sites for CO oxidation. In addition, active oxygen species indicated by the O 1 s XPS spectrum and improved synergistic effect between NiO and Co3O4 reflected by H2-TPR, further explain the enhanced performance of the HLDO catalysts. The presented strategy for controlled design and synthesis of hollow multicomponent metal oxides will provide prospects in developing highly effective catalysts.

  7. NOx formation from the combustion of monodisperse n-heptane sprays doped with fuel-nitrogen additives

    NASA Technical Reports Server (NTRS)

    Sarv, Hamid; Cernansky, Nicholas P.

    1989-01-01

    A series of experiments with simulated synthetic fuels were conducted in order to investigate the effect of droplet size on the conversion of fuel-nitrogen to NOx. Pyridine and pyrrole were added to n-heptane as nitrogen-containing additives and burned as monodisperse fuel droplets under various operating conditions in a spray combustion facility. The experimental results indicate that under stoichiometric and fuel-rich conditions, reducing the droplet size increases the efficiency of fuel-N conversion to NOx. This observation is associated with improved oxidation of the pyrolysis fragments of the additive by better oxygen penetration through the droplet flame zone. The dominant reactions by which fuel-N is transformed to NOx were also considered analytically by a premixed laminar flame code. The calculations are compared to the small droplet size results.

  8. Zirconium-based conversion film formation on zinc, aluminium and magnesium oxides and their interactions with functionalized molecules

    NASA Astrophysics Data System (ADS)

    Fockaert, L. I.; Taheri, P.; Abrahami, S. T.; Boelen, B.; Terryn, H.; Mol, J. M. C.

    2017-11-01

    Zirconium-based conversion treatment of zinc, aluminium and magnesium oxides have been studied in-situ using ATR-FTIR in a Kretschmann geometry. This set-up was coupled to an electrochemical cell, which allowed to obtain chemical and electrochemical information simultaneously as a function of conversion time. This elucidated the strong relation between physico-chemical surface properties and zirconium-based conversion kinetics. Whereas the surface hydroxyl density of zinc and aluminium increased during conversion, magnesium (hydr)oxide was shown to dissolve in the acid solution. Due to this dissolution, strong surface alkalization can be expected, explaining the rapid conversion kinetics. AES depth profiling was used to determine the final oxide thickness and elemental composition. This confirmed that magnesium is most active and forms a zirconium oxide layer approximately 10 times thicker than zinc. On the other hand, the presence of zirconium oxide on aluminium is very low and can be considered as not fully covering the metal oxide. Additionally, the converted oxide chemistry was related to the bonding mechanisms of amide functionalized molecules using ATR-FTIR and XPS. It was shown that inclusion of zirconium altered the acid-base properties, increasing the substrate proton donating capabilities in case of magnesium oxide and increasing hydrogen bonding and Bronsted interactions due to increased surface hydroxide fractions on zinc and aluminium substrates.

  9. Innovative oxide materials for electrochemical energy conversion and oxygen separation

    NASA Astrophysics Data System (ADS)

    Belousov, V. V.

    2017-10-01

    Ion-conducting solid metal oxides are widely used in high-temperature electrochemical devices for energy conversion and oxygen separation. However, liquid metal oxides possessing unique electrochemical properties still remain of limited use. The review demonstrates the potential for practical applications of molten oxides. The transport properties of molten oxide materials are discussed. The emphasis is placed on the chemical diffusion of oxygen in the molten oxide membrane materials for electrochemical energy conversion and oxygen separation. The thermodynamics of these materials is considered. The dynamic polymer chain model developed to describe the oxygen ion transport in molten oxides is discussed. Prospects for further research into molten oxide materials are outlined. The bibliography includes 145 references.

  10. One-step synthesis of vertically aligned anatase thornbush-like TiO2 nanowire arrays on transparent conducting oxides for solid-state dye-sensitized solar cells.

    PubMed

    Roh, Dong Kyu; Chi, Won Seok; Ahn, Sung Hoon; Jeon, Harim; Kim, Jong Hak

    2013-08-01

    Herein, we report a facile synthesis of high-density anatase-phase vertically aligned thornbush-like TiO2 nanowires (TBWs) on transparent conducting oxide glasses. Morphologically controllable TBW arrays of 9 μm in length are generated through a one-step hydrothermal reaction at 200 °C over 11 h using potassium titanium oxide oxalate dehydrate, diethylene glycol (DEG), and water. The TBWs consist of a large number of nanoplates or nanorods, as confirmed by SEM and TEM imaging. The morphologies of TBWs are controllable by adjusting DEG/water ratios. TBW diameters gradually decrease from 600 (TBW600) to 400 (TBW400) to 200 nm (TBW200) and morphologies change from nanoplates to nanorods with an increase in DEG content. TBWs are utilized as photoanodes for quasi-solid-state dye-sensitized solar cells (qssDSSCs) and solid-state DSSCs (ssDSSCs). The energy-conversion efficiency of qssDSSCs is in the order: TBW200 (5.2%)>TBW400 (4.5%)>TBW600 (3.4%). These results can be attributed to the different surface areas, light-scattering effects, and charge transport rates, as confirmed by dye-loading measurements, reflectance spectroscopy, and incident photon-to-electron conversion efficiency and intensity-modulated photovoltage spectroscopy/intensity-modulated photocurrent spectroscopy analyses. TBW200 is further treated with a graft-copolymer-directed organized mesoporous TiO2 to increase the surface area and interconnectivity of TBWs. As a result, the energy-conversion efficiency of the ssDSSC increases to 6.7% at 100 mW cm(-2) , which is among the highest values for N719-dye-based ssDSSCs. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Selective reduction of N-oxides to amines: application to drug metabolism.

    PubMed

    Kulanthaivel, Palaniappan; Barbuch, Robert J; Davidson, Rita S; Yi, Ping; Rener, Gregory A; Mattiuz, Edward L; Hadden, Chad E; Goodwin, Lawrence A; Ehlhardt, William J

    2004-09-01

    Phase I oxidative metabolism of nitrogen-containing drug molecules to their corresponding N-oxides is a common occurrence. There are instances where liquid chromatography/tandem mass spectometry techniques are inadequate to distinguish this pathway from other oxidation processes, including C-hydroxylations and other heteroatom oxidations, such as sulfur to sulfoxide. Therefore, the purpose of the present study was to develop and optimize an efficient and practical chemical method to selectively convert N-oxides to their corresponding amines suitable for drug metabolism applications. Our results indicated that efficient conversion of N-oxides to amines could be achieved with TiCl(3) and poly(methylhydrosiloxane). Among them, we found TiCl(3) to be a facile and easy-to-use reagent, specifically applicable to drug metabolism. There are a few reports describing the use of TiCl(3) to reduce N-O bonds in drug metabolism studies, but this methodology has not been widely used. Our results indicated that TiCl(3) is nearly as efficient when the reductions were carried out in the presence of biological matrices, including plasma and urine. Finally, we have shown a number of examples where TiCl(3) can be successfully used to selectively reduce N-oxides in the presence of sulfoxides and other labile groups.

  12. ANA position statement on privatization and for-profit conversion. American Nurses Association.

    PubMed

    1998-01-01

    The American Nurses Association (ANA) believes that the health of communities benefits from a mix of health care facilities, including both public and nonprofit private facilities where feasible. ANA is concerned by the rate of conversion of nonprofit facilities and plans to for-profit status. Privatization of public facilities and the conversion of nonprofit facilities and health plans to for-profit status requires careful public oversight to ensure continued access to affordable, quality services, including a maintenance of uncompensated care; a fair accounting of the assets of the entity being privatized or converted; and an assurance that converted assets are used to maintain and improve access to affordable, safe and quality health care services. The rights and benefits of employees must be carefully safe-guarded in any privatization or conversion move. All hospitals, regardless of ownership or tax status, should be held accountable for the delivery of safe, quality services, and should be required to disclose data regarding staffing, patient outcomes, cost and delivery of uncompensated care. Continued data collection will be necessary to guide further development of public policy to address privatization and for-profit conversion.

  13. Non-proliferation, safeguards, and security for the fissile materials disposition program immobilization alternatives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duggan, R.A.; Jaeger, C.D.; Tolk, K.M.

    1996-05-01

    The Department of Energy is analyzing long-term storage and disposition alternatives for surplus weapons-usable fissile materials. A number of different disposition alternatives are being considered. These include facilities for storage, conversion and stabilization of fissile materials, immobilization in glass or ceramic material, fabrication of fissile material into mixed oxide (MOX) fuel for reactors, use of reactor based technologies to convert material into spent fuel, and disposal of fissile material using geologic alternatives. This paper will focus on how the objectives of reducing security and proliferation risks are being considered, and the possible facility impacts. Some of the areas discussed inmore » this paper include: (1) domestic and international safeguards requirements, (2) non-proliferation criteria and measures, (3) the threats, and (4) potential proliferation, safeguards, and security issues and impacts on the facilities. Issues applicable to all of the possible disposition alternatives will be discussed in this paper. However, particular attention is given to the plutonium immobilization alternatives.« less

  14. 77 FR 60981 - Kinder Morgan Interstate Gas Transmission L.L.C.; Notice of Intent To Prepare an Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... Pony Express Pipeline Conversion Project and Request for Comments on Environmental Issues The staff of... (EA) that will discuss the environmental impacts of the Pony Express Pipeline Conversion Project involving conversion of facilities from natural gas to oil and construction and operation of new facilities...

  15. Constructing hierarchical interfaces: TiO 2-supported PtFe-FeO x nanowires for room temperature CO oxidation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhu, Huiyuan; Wu, Zili; Dong, Su

    2015-08-05

    This is a report of a facile approach to constructing catalytic active hierarchical interfaces in one-dimensional (1D) nanostructure, exemplified by the synthesis of TiO 2-supported PtFe–FeO x nanowires (NWs). The hierarchical interface, constituting atomic level interactions between PtFe and FeO x within each NW and the interactions between NWs and support (TiO 2), enables CO oxidation with 100% conversion at room temperature. We identify the role of the two interfaces by probing the CO oxidation reaction with isotopic labeling experiments. Both the oxygen atoms (Os) in FeO x and TiO 2 participate in the initial CO oxidation, facilitating the reactionmore » through a redox pathway. Moreover, the intact 1D structure leads to the high stability of the catalyst. After 30 h in the reaction stream, the PtFe–FeO x/TiO2 catalyst exhibits no activity decay. These results provide a general approach and new insights into the construction of hierarchical interfaces for advanced catalysis.« less

  16. Oxidative coupling of methane using inorganic membrane reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Y.H.; Moser, W.R.; Dixon, A.G.

    1995-12-31

    The goal of this research is to improve the oxidative coupling of methane in a catalytic inorganic membrane reactor. A specific target is to achieve conversion of methane to C{sub 2} hydrocarbons at very high selectivity and relatively higher yields than in fixed bed reactors by controlling the oxygen supply through the membrane. A membrane reactor has the advantage of precisely controlling the rate of delivery of oxygen to the catalyst. This facility permits balancing the rate of oxidation and reduction of the catalyst. In addition, membrane reactors minimize the concentration of gas phase oxygen thus reducing non selective gasmore » phase reactions, which are believed to be a main route for formation of CO{sub x} products. Such gas phase reactions are a cause for decreased selectivity in oxidative coupling of methane in conventional flow reactors. Membrane reactors could also produce higher product yields by providing better distribution of the reactant gases over the catalyst than the conventional plug flow reactors. Modeling work which aimed at predicting the observed experimental trends in porous membrane reactors was also undertaken in this research program.« less

  17. Poly(3,4-ethylenedioxythiophene)/reduced graphene oxide composites as counter electrodes for high efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ma, Jinfu; Yuan, Shenghua; Yang, Shaolin; Lu, Hui; Li, Yingtao

    2018-05-01

    A facile, low cost, easy-controllable method to prepare Poly(3,4-ethylenedioxythiophene) (PEDOT)/reduced graphene oxide (rGO) composites by electrochemical deposition onto fluorinated tin oxide (FTO) as counter electrodes (CEs) in high performance dye-sensitized solar cells (DSSCs) is reported. The electro-deposition process was accomplished by electro-polymerization of graphene oxide (GO)/PEDOT composites onto FTO substrates followed by electrochemical reduction of the GO component. Electrochemical measurements show that the I-/I3- catalytic activity of the as-prepared PEDOT/rGO CE is improved compared with that of the pure PEDOT and PEDOT/GO electrode. Through the analysis of photoelectric properties, the performance of the electrodes fabricated with different polymerization times are compared, and the optimal preparation condition is determined. The photoelectric conversion efficiency (PCE) of the DSSC assembled with PEDOT/rGO electrode reaches 7.79%, close to 8.33% of the cell with Platinum (Pt) electrode, and increases by 13.2% compared with 6.88% of the device with the PEDOT electrode.

  18. High-flux solar-driven thermochemical dissociation of CO2 and H2O using nonstoichiometric ceria.

    PubMed

    Chueh, William C; Falter, Christoph; Abbott, Mandy; Scipio, Danien; Furler, Philipp; Haile, Sossina M; Steinfeld, Aldo

    2010-12-24

    Because solar energy is available in large excess relative to current rates of energy consumption, effective conversion of this renewable yet intermittent resource into a transportable and dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low conversion efficiencies, particularly with CO(2) reduction, as well as utilization of precious materials have limited the practical generation of solar fuels. By using a solar cavity-receiver reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO(2) and H(2)O, yielding CO and H(2), respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale and design rather than by chemistry.

  19. Phase and composition controllable synthesis of cobalt manganese spinel nanoparticles towards efficient oxygen electrocatalysis.

    PubMed

    Li, Chun; Han, Xiaopeng; Cheng, Fangyi; Hu, Yuxiang; Chen, Chengcheng; Chen, Jun

    2015-06-04

    Spinel-type oxides are technologically important in many fields, including electronics, magnetism, catalysis and electrochemical energy storage and conversion. Typically, these materials are prepared by conventional ceramic routes that are energy consuming and offer limited control over shape and size. Moreover, for mixed-metal oxide spinels (for example, Co(x)Mn(3-x)O4), the crystallographic phase sensitively correlates with the metal ratio, posing great challenges to synthesize active product with simultaneously tuned phase and composition. Here we report a general synthesis of ultrasmall cobalt manganese spinels with tailored structural symmetry and composition through facile solution-based oxidation-precipitation and insertion-crystallization process at modest condition. As an example application, the nanocrystalline spinels catalyse the oxygen reduction/evolution reactions, showing phase and composition co-dependent performance. Furthermore, the mild synthetic strategy allows the formation of homogeneous and strongly coupled spinel/carbon nanocomposites, which exhibit comparable activity but superior durability to Pt/C and serve as efficient catalysts to build rechargeable Zn-air and Li-air batteries.

  20. Conversion coatings prepared or treated with calcium hydroxide solutions

    NASA Technical Reports Server (NTRS)

    Maxey, Jason (Inventor); Nelson, Carl (Inventor); Eylem, Cahit (Inventor); Minevski, Zoran (Inventor); Clarke, Eric (Inventor)

    2002-01-01

    A conversion coating process that forms a stable and corrosion-resistant oxide layer on metal or metal oxide substrates or layers. Particularly, the conversion coating process involves contacting the metal or metal oxide substrate or layer with the aqueous calcium hydroxide solutions in order to convert the surface of the substrate to a stable metal oxide layer or coating. According to the present invention, the calcium hydroxide solution is prepared by removing carbon dioxide from water or an aqueous solution before introducing the calcium hydroxide. In this manner, formation of calcium carbonate particles is avoided and the porosity of the conversion coating produced by the calcium hydroxide solution is reduced to below about 1%.

  1. Magnetically Recoverable Pd/Fe 3O 4 Core-Shell Nanowire Clusters with Increased Hydrogenation Activity

    DOE PAGES

    Watt, John; Kotula, Paul G.; Huber, Dale L.

    2017-02-06

    Core-shell nanostructures are promising candidates for the next generation of catalysts due to synergistic effects which can arise from having two active species in close contact, leading to increased activity. Likewise, catalysts displaying added functionality, such as a magnetic response, can increase their scientific and industrial potential. Here, we synthesize Pd/Fe 3O 4 core-shell nanowire clusters and apply them as hydrogenation catalysts for an industrially important hydrogenation reaction; the conversion of acetophenone to 1-phenylethanol. During synthesis, the palladium nanowires self-assemble into clusters which act as a high surface area framework for the growth of a magnetic iron oxide shell. Wemore » demonstrate excellent catalytic activity due to the presence of palladium while the strong magnetic properties provided by the iron oxide shell enable facile catalyst recovery.« less

  2. Ultralight mesoporous magnetic frameworks by interfacial assembly of Prussian blue nanocubes.

    PubMed

    Kong, Biao; Tang, Jing; Wu, Zhangxiong; Wei, Jing; Wu, Hao; Wang, Yongcheng; Zheng, Gengfeng; Zhao, Dongyuan

    2014-03-10

    A facile approach for the synthesis of ultralight iron oxide hierarchical structures with tailorable macro- and mesoporosity is reported. This method entails the growth of porous Prussian blue (PB) single crystals on the surface of a polyurethane sponge, followed by in situ thermal conversion of PB crystals into three-dimensional mesoporous iron oxide (3DMI) architectures. Compared to previously reported ultralight materials, the 3DMI architectures possess hierarchical macro- and mesoporous frameworks with multiple advantageous features, including high surface area (ca. 117 m(2) g(-1)) and ultralow density (6-11 mg cm(-3)). Furthermore, they can be synthesized on a kilogram scale. More importantly, these 3DMI structures exhibit superparamagnetism and tunable hydrophilicity/hydrophobicity, thus allowing for efficient multiphase interfacial adsorption and fast multiphase catalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Photoactive films of photosystem I on transparent reduced graphene oxide electrodes.

    PubMed

    Darby, Emily; LeBlanc, Gabriel; Gizzie, Evan A; Winter, Kevin M; Jennings, G Kane; Cliffel, David E

    2014-07-29

    Photosystem I (PSI) is a photoactive electron-transport protein found in plants that participates in the process of photosynthesis. Because of PSI's abundance in nature and its efficiency with charge transfer and separation, there is a great interest in applying the protein in photoactive electrodes. Here, we developed a completely organic, transparent, conductive electrode using reduced graphene oxide (RGO) on which a multilayer of PSI could be deposited. The resulting photoactive electrode demonstrated current densities comparable to that of a gold electrode modified with a multilayer film of PSI and significantly higher than that of a graphene electrode modified with a monolayer film of PSI. The relatively large photocurrents produced by integrating PSI with RGO and using an opaque, organic mediator can be applied to the facile production of more economic solar energy conversion devices.

  4. Passive, Low Cost Neutron Detectors for Neutron Diagnostics at the National Ignition Facility

    DTIC Science & Technology

    2013-03-01

    Facility PTFE Polytetrafluoroethylene TLD Thermoluminescent Dosimeter α Conversion Coefficient (Conversion...because they required a large investment in automated track counting equipment. Thermoluminescent dosimeters ( TLDs ) remained as a viable option. They...necessary to predict radiation damage to measurement electronics . Due to programmatic and facility limitations, traditional neutron measurement

  5. One-step route to a hybrid TiO2/Ti x W1-x N nanocomposite by in situ selective carbothermal nitridation.

    PubMed

    Schnepp, Zoë; Hollamby, Martin J; Tanaka, Masahiko; Matsushita, Yoshitaka; Katsuya, Yoshio; Sakka, Yoshio

    2012-06-01

    Metal oxide/nitride nanocomposites have many existing and potential applications, e.g. in energy conversion or ammonia synthesis. Here, a hybrid oxide/nitride nanocomposite (anatase/Ti x W 1- x N) was synthesized by an ammonia-free sol-gel route. Synchrotron x-ray diffraction, complemented with electron microscopy and thermogravimetric analysis, was used to study the structure, composition and mechanism of formation of the nanocomposite. The nanocomposite contained nanoparticles (<5 nm diameter) of two highly intermixed phases. This was found to arise from controlled nucleation and growth of a single oxide intermediate from the gel precursor, followed by phase separation and in situ selective carbothermal nitridation. Depending on the preparation conditions, the composition varied from anatase/Ti x W 1- x N at low W content to an isostructural mixture of Ti-rich and W-rich Ti x W 1- x N at high W content. In situ selective carbothermal nitridation offers a facile route to the synthesis of nitride-oxide nanocomposites. This conceptually new approach is a significant advance from previous methods, which generally require ammonolysis of a pre-synthesized oxide.

  6. An electrochemical label-free and sensitive thrombin aptasensor based on graphene oxide modified pencil graphite electrode.

    PubMed

    Ahour, F; Ahsani, M K

    2016-12-15

    In this work, we tactfully constructed a novel label-free electrochemical aptasensor for rapid and facile detection of thrombin using graphene oxide (GO) and thrombin binding aptamer (TBA). The strategy relies on the preferential adsorption of single-stranded DNA (ssDNA) to GO over aptamer-target complexes. The TBA-thrombin complex formation was monitored by differential pulse voltammetry (DPV) using the guanine oxidation signal. In the absence of thrombin, the aptamers adsorbed onto the surface of GO leading to a strong background guanine oxidation signal. Conversely, in the presence of thrombin, the conformational transformation of TBA after incubating with the thrombin solution and formation of the aptamer-thrombin complexes which had weak binding ability to GO, leads to the desorption of TBA-thrombin complex from electrode surface and significant oxidation signal decrease. The selectivity of the biosensor was studied using other biological substances. The biosensor's signal was proportional to the thrombin concentration from 0.1 to 10nM with a detection limit of 0.07nM. Particularly, the proposed method could be widely applied to the aptamer-based determination of other target analytes. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Facile fabrication of nanofluidic diode membranes using anodic aluminium oxide

    NASA Astrophysics Data System (ADS)

    Wu, Songmei; Wildhaber, Fabien; Vazquez-Mena, Oscar; Bertsch, Arnaud; Brugger, Juergen; Renaud, Philippe

    2012-08-01

    Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al2O3/SiO2 (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al2O3 (positive) and SiO2 (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion.Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al2O3/SiO2 (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al2O3 (positive) and SiO2 (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion. Electronic supplementary information (ESI) available: Pattern transfer of local AAO mask into Si layers of different thickness; characterization of the Ag/AgCl electrodes and the cell constant; control experiments of mono-charged nanopore membranes; and simulation of ionic transport in nanofluidic diodes. See DOI: 10.1039/c2nr31243c

  8. DUF6 Conversion Facility EIS Alternatives

    Science.gov Websites

    in the Depleted UF6 Conversion Facility EISs. Proposed Action The proposed action evaluated in each Action Alternative No Action Alternative. Under the "no action" alternative, cylinder

  9. A facile and green method towards coal-based fluorescent carbon dots with photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Hu, Shengliang; Wei, Zhijia; Chang, Qing; Trinchi, Adrian; Yang, Jinlong

    2016-08-01

    One of the most widely used methods for exfoliating crystalline nanocarbon is via strong oxidizing acid treatment of bulk carbon sources, such as graphite, carbon black and coal. Not only is such method dangerous and accompanied by the liberation of toxic gases, it is also plagued by issues of purity, requiring the thorough and costly removal of the excess oxidizing acids and salts formed during the process. Herein we report a facile, green and inexpensive top-down strategy towards fluorescent carbon dots (CDs) from coal without incurring the burden of tedious or inefficient post-processing steps and facing the danger of highly toxic gas liberation. The presented approach shows a high yield and great potential for carbon dot production scale-up using coal, one of our most abundant and low-cost resources. The prepared CDs demonstrate photocatalytic behavior capable of rapidly degrading organic dyes under visible light. Our findings may lead to alternative uses of coal, particularly for applications including the treatment of environmental pollution, solar energy conversion or storage, and highlight coal's applicability in areas other than energy producing via burning of this great resource.

  10. Conversion Reaction-Based Oxide Nanomaterials for Lithium Ion Battery Anodes.

    PubMed

    Yu, Seung-Ho; Lee, Soo Hong; Lee, Dong Jun; Sung, Yung-Eun; Hyeon, Taeghwan

    2016-04-27

    Developing high-energy-density electrodes for lithium ion batteries (LIBs) is of primary importance to meet the challenges in electronics and automobile industries in the near future. Conversion reaction-based transition metal oxides are attractive candidates for LIB anodes because of their high theoretical capacities. This review summarizes recent advances on the development of nanostructured transition metal oxides for use in lithium ion battery anodes based on conversion reactions. The oxide materials covered in this review include oxides of iron, manganese, cobalt, copper, nickel, molybdenum, zinc, ruthenium, chromium, and tungsten, and mixed metal oxides. Various kinds of nanostructured materials including nanowires, nanosheets, hollow structures, porous structures, and oxide/carbon nanocomposites are discussed in terms of their LIB anode applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Nitrous oxide for labor analgesia: Utilization and predictors of conversion to neuraxial analgesia.

    PubMed

    Sutton, Caitlin D; Butwick, Alexander J; Riley, Edward T; Carvalho, Brendan

    2017-08-01

    We examined the characteristics of women who choose nitrous oxide for labor analgesia and identified factors that predict conversion from nitrous oxide to labor neuraxial analgesia. Retrospective descriptive study. Labor and Delivery Ward. 146 pregnant women who used nitrous oxide for analgesia during labor and delivery between September 2014 and September 2015. Chart review only. Demographic, obstetric, and intrapartum characteristics of women using nitrous oxide were examined. Multivariable logistic regression was performed to identify factors associated with conversion from nitrous oxide to neuraxial analgesia. Data are presented as n (%), median [IQR], adjusted relative risk (aRR), and 95% confidence intervals (CI) as appropriate. During the study period, 146 women used nitrous oxide for labor analgesia (accounting for 3% of the total deliveries). The majority (71.9%) of women who used nitrous oxide were nulliparous, and over half (51.9%) had expressed an initial preference for "nonmedical birth." The conversion rate to neuraxial blockade was 63.2%, compared to a concurrent institutional rate of 85.1% in women who did not use nitrous oxide. Factors associated with conversion from nitrous oxide to neuraxial blockade were labor induction (aRR=2.0, CI 1.2-3.3) and labor augmentation (aRR=1.7, CI 1.0-2.9). Only a small number of women opted to use nitrous oxide during labor, analgesia was minimal, and most converted to neuraxial analgesia. Women with induced and augmented labors should be counseled about the increased likelihood that they will convert to neuraxial analgesia. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Biocatalytic conversion of ethylene to ethylene oxide using an engineered toluene monooxygenase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carlin, DA; Bertolani, SJ; Siegel, JB

    Mutants of toluene o-xylene monooxygenase are demonstrated to oxidize ethylene to ethylene oxide in vivo at yields of >99%. The best mutant increases ethylene oxidation activity by >5500-fold relative to the native enzyme. This is the first report of a recombinant enzyme capable of carrying out this industrially significant chemical conversion.

  13. Biocatalytic conversion of ethylene to ethylene oxide using an engineered toluene monooxygenase.

    PubMed

    Carlin, D A; Bertolani, S J; Siegel, J B

    2015-02-11

    Mutants of toluene o-xylene monooxygenase are demonstrated to oxidize ethylene to ethylene oxide in vivo at yields of >99%. The best mutant increases ethylene oxidation activity by >5500-fold relative to the native enzyme. This is the first report of a recombinant enzyme capable of carrying out this industrially significant chemical conversion.

  14. Facile Dehydrogenation of Ethane on the IrO2(110) Surface.

    PubMed

    Bian, Yingxue; Kim, Minkyu; Li, Tao; Asthagiri, Aravind; Weaver, Jason F

    2018-02-21

    Realizing the efficient and selective conversion of ethane to ethylene is important for improving the utilization of hydrocarbon resources, yet remains a major challenge in catalysis. Herein, ethane dehydrogenation on the IrO 2 (110) surface is investigated using temperature-programmed reaction spectroscopy (TPRS) and density functional theory (DFT) calculations. The results show that ethane forms strongly bound σ-complexes on IrO 2 (110) and that a large fraction of the complexes undergo C-H bond cleavage during TPRS at temperatures below 200 K. Continued heating causes as much as 40% of the dissociated ethane to dehydrogenate and desorb as ethylene near 350 K, with the remainder oxidizing to CO x species. Both TPRS and DFT show that ethylene desorption is the rate-controlling step in the conversion of ethane to ethylene on IrO 2 (110) during TPRS. Partial hydrogenation of the IrO 2 (110) surface is found to enhance ethylene production from ethane while suppressing oxidation to CO x species. DFT predicts that hydrogenation of reactive oxygen atoms of the IrO 2 (110) surface effectively deactivates these sites as H atom acceptors, and causes ethylene desorption to become favored over further dehydrogenation and oxidation of ethane-derived species. The study reveals that IrO 2 (110) exhibits an exceptional ability to promote ethane dehydrogenation to ethylene near room temperature, and provides molecular-level insights for understanding how surface properties influence selectivity toward ethylene production.

  15. Facile electrosynthesis of silicon carbide nanowires from silica/carbon precursors in molten salt.

    PubMed

    Zou, Xingli; Ji, Li; Lu, Xionggang; Zhou, Zhongfu

    2017-08-30

    Silicon carbide nanowires (SiC NWs) have attracted intensive attention in recent years due to their outstanding performances in many applications. A large-scale and facile production of SiC NWs is critical to its successful application. Here, we report a simple method for the production of SiC NWs from inexpensive and abundantly available silica/carbon (SiO 2 /C) precursors in molten calcium chloride. The solid-to-solid electroreduction and dissolution-electrodeposition mechanisms can easily lead to the formation of homogenous SiC NWs. This template/catalyst-free approach greatly simplifies the synthesis procedure compared to conventional methods. This general strategy opens a direct electrochemical route for the conversion of SiO 2 /C into SiC NWs, and may also have implications for the electrosynthesis of other micro/nanostructured metal carbides/composites from metal oxides/carbon precursors.

  16. Effect of composition and calcination temperature of ceria-zirconia-alumina mixed oxides on catalytic performances of ethanol conversion

    NASA Astrophysics Data System (ADS)

    Chuklina, S. G.; Maslenkova, S. A.; Pylinina, A. I.; Podzorova, L. I.; Ilyicheva, A. A.

    2017-02-01

    In the present study, we investigated the effect of preparation method, phase composition and calcination temperature of the (Ce-TZP) - Al2O3 mixed oxides on their structural features and catalytic performance in ethanol conversion. Ceria-zirconia-alumina mixed oxides with different (Ce+Zr)/Al atomic ratios were prepared via sol-gel method. Catalytic activity and selectivity were investigated for ethanol conversion to acetaldehyde, ethylene and diethyl ether.

  17. Safety analysis, 200 Area, Savannah River Plant: Separations area operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Perkins, W.C.; Lee, R.; Allen, P.M.

    1991-07-01

    The nev HB-Line, located on the fifth and sixth levels of Building 221-H, is designed to replace the aging existing HB-Line production facility. The nev HB-Line consists of three separate facilities: the Scrap Recovery Facility, the Neptunium Oxide Facility, and the Plutonium Oxide Facility. There are three separate safety analyses for the nev HB-Line, one for each of the three facilities. These are issued as supplements to the 200-Area Safety Analysis (DPSTSA-200-10). These supplements are numbered as Sup 2A, Scrap Recovery Facility, Sup 2B, Neptunium Oxide Facility, Sup 2C, Plutonium Oxide Facility. The subject of this safety analysis, the, Plutoniummore » Oxide Facility, will convert nitrate solutions of {sup 238}Pu to plutonium oxide (PuO{sub 2}) powder. All these new facilities incorporate improvements in: (1) engineered barriers to contain contamination, (2) barriers to minimize personnel exposure to airborne contamination, (3) shielding and remote operations to decrease radiation exposure, and (4) equipment and ventilation design to provide flexibility and improved process performance.« less

  18. Conversion of NO with a catalytic packed-bed dielectric barrier discharge reactor

    NASA Astrophysics Data System (ADS)

    Xu, CAO; Weixuan, ZHAO; Renxi, ZHANG; Huiqi, HOU; Shanping, CHEN; Ruina, ZHANG

    2017-11-01

    This paper discusses the conversion of nitric oxide (NO) with a low-temperature plasma induced by a catalytic packed-bed dielectric barrier discharge (DBD) reactor. Alumina oxide (Al2O3), glass (SiO2) and zirconium oxide (ZrO2), three different spherical packed materials of the same size, were each present in the DBD reactor. The NO conversion under varying input voltage and specific energy density, and the effects of catalysts (titanium dioxide (TiO2) and manganese oxide (MnO x ) coated on Al2O3) on NO conversion were investigated. The experimental results showed that NO conversion was greatly enhanced in the presence of packed materials in the reactor, and the catalytic packed bed of MnO x /Al2O3 showed better performance than that of TiO2/Al2O3. The surface and crystal structures of the materials and catalysts were characterized through scanning electron microscopy analysis. The final products were clearly observed by a Fourier transform infrared spectrometer and provided a better understanding of NO conversion.

  19. Copper-Mediated Fluorination of Arylboronate Esters. Identification of a Copper(III) Fluoride Complex

    PubMed Central

    Fier, Patrick S.; Luo, Jingwei; Hartwig, John F.

    2013-01-01

    A method for the direct conversion of arylboronate esters to aryl fluorides under mild conditions with readily available reagents is reported. Tandem reactions have also been developed for the fluorination of arenes and aryl bromides through aryl-boronate ester intermediates. Mechanistic studies suggest that this fluorination reaction occurs through facile oxidation of Cu(I) to Cu(III) followed by rate-limiting transmetallation of a bound arylboronate to Cu(III). Fast C-F reductive elimination is proposed to occur from an aryl-copper(III)-fluoride complex. Cu(III) intermediates have been generated independently and identified by NMR spectroscopy and ESI-MS. PMID:23384209

  20. Formation of alcohol conversion catalysts

    DOEpatents

    Wachs, Israel E.; Cai, Yeping

    2001-01-01

    The method of the present invention involves a composition containing an intimate mixture of (a) metal oxide support particles and (b) a catalytically active metal oxide from Groups VA, VIA, or VIIA, its method of manufacture, and its method of use for converting alcohols to aldehydes. During the conversion process, catalytically active metal oxide from the discrete catalytic metal oxide particles migrates to the oxide support particles and forms a monolayer of catalytically active metal oxide on the oxide support particle to form a catalyst composition having a higher specific activity than the admixed particle composition.

  1. 7 CFR 1450.104 - Signup.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments... biomass conversion facility. The application must be submitted to the FSA county office and approved by CCC before any payment is made by the qualified biomass conversion facility for the eligible material...

  2. 7 CFR 1450.104 - Signup.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments... biomass conversion facility. The application must be submitted to the FSA county office and approved by CCC before any payment is made by the qualified biomass conversion facility for the eligible material...

  3. 7 CFR 1450.104 - Signup.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments... biomass conversion facility. The application must be submitted to the FSA county office and approved by CCC before any payment is made by the qualified biomass conversion facility for the eligible material...

  4. 7 CFR 1450.104 - Signup.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments... biomass conversion facility. The application must be submitted to the FSA county office and approved by CCC before any payment is made by the qualified biomass conversion facility for the eligible material...

  5. Application of a Chemiluminescence Detector for the Measurement of Total Oxides of Nitrogen and Ammonia in the Atmosphere

    NASA Technical Reports Server (NTRS)

    Hodgeson, J. A.; Bell, J. P.; Rehme, K. A.; Krost, K. J.; Stevens, R. K.

    1971-01-01

    By means of the thermal conversion of nitrogen dioxide to the nitric oxide, the chemiluminescent nitric oxide monitor, based on the nitric oxide plus ozone reaction, may be used for monitoring nitrogen dioxide plus nitric oxide (NO(x)). Under conditions previously described, ammonia is also converted to nitric oxide and therefore interferes. A metal surface, gold wool or stainless steel, operated at two different temperatures has been used to convert only nitrogen dioxide or nitrogen dioxide plus ammonia. Quantitative conversion of nitrogen dioxide to nitric oxide has been obtained at temperatures as low as 200 C. Conversion of ammonia is effected at temperatures of 300 C or higher. By the addition of a converter the basic nitric oxide monitor may be used for measuring NO(x) or NO(x) plus ammonia. As an alternate mode, for a fixed high temperature, a specific scrubber is described for removing NH3 without affecting NO2 concentrations.

  6. Novel Preparation of Nano-Composite CuO-Cr2O3 Using Ctab-Template Method and Efficient for Hydrogenation of Biomass-Derived Furfural

    NASA Astrophysics Data System (ADS)

    Yan, Kai; Wu, Xu; An, Xia; Xie, Xianmei

    2013-02-01

    A simple route to fabricate nano-composite oxides CuO-Cr2O3 using hexadecyltrimethylammonium bromide (CTAB)-templated Cu-Cr hydrotalcite as the precursor is presented. This novel method is based on CTAB-templating effect for mesostructure directing and using the cheap metal nitrate, followed by removal of CTAB. It was indicated that the nano-composite CuO-Cr2O3 was formed during the removal of CTAB. X-ray diffraction (XRD) and transitional electronic microscopy (TEM) revealed nice nano-composite oxides CuO-Cr2O3 were formed with high crystallinity. N2 adsorption and desorption indicated that a high surface area of 170.5 m2/g with a pore size of 2.7 nm of the nano-composite CuO-Cr2O3 was facilely resulted. The as-synthesized nano-composite oxides CuO-Cr2O3 display good catalytic activities for hydrogenation of furfural to furfuryl alcohol, whereas 86% selectivity was achieved at 75% conversion of furfural.

  7. Facile synthesis of nitrogen-doped reduced graphene oxide as an efficient counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wei, Liguo; Wang, Ping; Yang, Yulin; Luo, Ruidong; Li, Jinqi; Gu, Xiaohu; Zhan, Zhaoshun; Dong, Yongli; Song, Weina; Fan, Ruiqing

    2018-04-01

    A nitrogen-doped reduced graphene oxide (N-RGO) nanosheet was synthesized by a simple hydrothermal method and characterized by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electrode microscopy. After being deposited as counter electrode film for dye-sensitized solar cells (DSSCs), it is found that the synthesized N-RGO nanosheet has smaller charge-transfer resistance and better electrocatalytic activity towards reduction of triiodide than the reduced graphene oxide (RGO) nanosheet. Consequently, the DSSCs based on the N-RGO counter electrode achieve an energy conversion efficiency of 4.26%, which is higher than that of the RGO counter electrode (2.85%) prepared under the same conditions, and comparable to the value (5.21%) obtained with the Pt counter electrode as a reference. This N-RGO counter electrode offers the advantages of not only saving the cost of Pt itself but also simplifying the process of counter electrode preparation. Therefore, an inexpensive N-RGO nanosheet is a promising counter electrode material to replace noble metal Pt. [Figure not available: see fulltext.

  8. Performance and Fabrication Status of TREAT LEU Conversion Conceptual Design Concepts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    IJ van Rooyen; SR Morrell; AE Wright

    2014-10-01

    Resumption of transient testing at the TREAT facility was approved in February 2014 to meet U.S. Department of Energy (DOE) objectives. The National Nuclear Security Administration’s Global Threat Reduction Initiative Convert Program is evaluating conversion of TREAT from its existing highly enriched uranium (HEU) core to a new core containing low enriched uranium (LEU). This paper describes briefly the initial pre-conceptual designs screening decisions with more detailed discussions on current feasibility, qualification and fabrication approaches. Feasible fabrication will be shown for a LEU fuel element assembly that can meet TREAT design, performance, and safety requirements. The statement of feasibility recognizesmore » that further development, analysis, and testing must be completed to refine the conceptual design. Engineering challenges such as cladding oxidation, high temperature material properties, and fuel block fabrication along with neutronics performance, will be highlighted. Preliminary engineering and supply chain evaluation provided confidence that the conceptual designs can be achieved.« less

  9. Biological conversion of biogas to methanol using methanotrophs isolated from solid-state anaerobic digestate.

    PubMed

    Sheets, Johnathon P; Ge, Xumeng; Li, Yueh-Fen; Yu, Zhongtang; Li, Yebo

    2016-02-01

    The aim of this work was to isolate methanotrophs (methane oxidizing bacteria) that can directly convert biogas produced at a commercial anaerobic digestion (AD) facility to methanol. A methanotrophic bacterium was isolated from solid-state anaerobic digestate. The isolate had characteristics comparable to obligate methanotrophs from the genus Methylocaldum. This newly isolated methanotroph grew on biogas or purified CH4 and successfully converted biogas from AD to methanol. Methanol production was achieved using several methanol dehydrogenase (MDH) inhibitors and formate as an electron donor. The isolate also produced methanol using phosphate with no electron donor or using formate with no MDH inhibitor. The maximum methanol concentration (0.43±0.00gL(-1)) and 48-h CH4 to methanol conversion (25.5±1.1%) were achieved using biogas as substrate and a growth medium containing 50mM phosphate and 80mM formate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Indium oxide/n-silicon heterojunction solar cells

    DOEpatents

    Feng, Tom; Ghosh, Amal K.

    1982-12-28

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  11. Noise measurements in a free-jet, flight simulation facility - Shear layer refraction and facility-to-flight corrections

    NASA Technical Reports Server (NTRS)

    Morfey, C. L.; Tester, B. J.

    1976-01-01

    The conversion of free-jet facility into equivalent flyover results is discussed. The essential problem is to 'calibrate out' the acoustic influence of the outer free-jet shear layer on the measurement, since this is absent in the flight case. Results are presented which illustrate the differences between current simplified models (vortex-sheet and geometric acoustics), and a more complete model based on the Lilley equation. Finally, the use of geometric acoustics for facility-to-flight data conversion is discussed.

  12. 76 FR 58049 - Atomic Safety and Licensing Board; Honeywell International, Inc.; Metropolis Works Uranium...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 40-3392-MLA; ASLBP No. 11-910-01-MLA-BD01] Atomic Safety and Licensing Board; Honeywell International, Inc.; Metropolis Works Uranium Conversion Facility... assurance for its Metropolis Works uranium conversion facility in Metropolis, Illinois. \\1\\ LBP-11-19, 74...

  13. 78 FR 25484 - License Amendment for Anadarko Petroleum Corporation, Bear Creek Facility, Converse County, Wyoming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-01

    ... NUCLEAR REGULATORY COMMISSION [Docket No.: 40-8452; NRC-2012-0095] License Amendment for Anadarko Petroleum Corporation, Bear Creek Facility, Converse County, Wyoming AGENCY: Nuclear Regulatory Commission... License SUA- 1310 issued to Anadarko Petroleum Corporation (APC or the licensee) to authorize alternate...

  14. Electrocatalytic N-Doped Graphitic Nanofiber - Metal/Metal Oxide Nanoparticle Composites.

    PubMed

    Tang, Hongjie; Chen, Wei; Wang, Jiangyan; Dugger, Thomas; Cruz, Luz; Kisailus, David

    2018-03-01

    Carbon-based nanocomposites have shown promising results in replacing commercial Pt/C as high-performance, low cost, nonprecious metal-based oxygen reduction reaction (ORR) catalysts. Developing unique nanostructures of active components (e.g., metal oxides) and carbon materials is essential for their application in next generation electrode materials for fuel cells and metal-air batteries. Herein, a general approach for the production of 1D porous nitrogen-doped graphitic carbon fibers embedded with active ORR components, (M/MO x , i.e., metal or metal oxide nanoparticles) using a facile two-step electrospinning and annealing process is reported. Metal nanoparticles/nanoclusters nucleate within the polymer nanofibers and subsequently catalyze graphitization of the surrounding polymer matrix and following oxidation, create an interconnected graphite-metal oxide framework with large pore channels, considerable active sites, and high specific surface area. The metal/metal oxide@N-doped graphitic carbon fibers, especially Co 3 O 4 , exhibit comparable ORR catalytic activity but superior stability and methanol tolerance versus Pt in alkaline solutions, which can be ascribed to the synergistic chemical coupling effects between Co 3 O 4 and robust 1D porous structures composed of interconnected N-doped graphitic nanocarbon rings. This finding provides a novel insight into the design of functional electrocatalysts using electrospun carbon nanomaterials for their application in energy storage and conversion fields. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Method for forming indium oxide/n-silicon heterojunction solar cells

    DOEpatents

    Feng, Tom; Ghosh, Amal K.

    1984-03-13

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  16. Carbothermic synthesis of 820 μm uranium nitride kernels: Literature review, thermodynamics, analysis, and related experiments

    NASA Astrophysics Data System (ADS)

    Lindemer, T. B.; Voit, S. L.; Silva, C. M.; Besmann, T. M.; Hunt, R. D.

    2014-05-01

    The US Department of Energy is developing a new nuclear fuel that would be less susceptible to ruptures during a loss-of-coolant accident. The fuel would consist of tristructural isotropic coated particles with uranium nitride (UN) kernels with diameters near 825 μm. This effort explores factors involved in the conversion of uranium oxide-carbon microspheres into UN kernels. An analysis of previous studies with sufficient experimental details is provided. Thermodynamic calculations were made to predict pressures of carbon monoxide and other relevant gases for several reactions that can be involved in the conversion of uranium oxides and carbides into UN. Uranium oxide-carbon microspheres were heated in a microbalance with an attached mass spectrometer to determine details of calcining and carbothermic conversion in argon, nitrogen, and vacuum. A model was derived from experiments on the vacuum conversion to uranium oxide-carbide kernels. UN-containing kernels were fabricated using this vacuum conversion as part of the overall process. Carbonitride kernels of ∼89% of theoretical density were produced along with several observations concerning the different stages of the process.

  17. 1. West facade of Plutonium Concentration Facility (Building 233S), ReductionOxidation ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West facade of Plutonium Concentration Facility (Building 233-S), Reduction-Oxidation Building (REDOX-202-S) to the right. Looking east. - Reduction-Oxidation Complex, Plutonium Concentration Facility, 200 West Area, Richland, Benton County, WA

  18. Method For Selective Catalytic Reduction Of Nitrogen Oxides

    DOEpatents

    Mowery-Evans, Deborah L.; Gardner, Timothy J.; McLaughlin, Linda I.

    2005-02-15

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  19. Method for selective catalytic reduction of nitrogen oxides

    DOEpatents

    Mowery-Evans, Deborah L [Broomfield, CO; Gardner, Timothy J [Albuquerque, NM; McLaughlin, Linda I [Albuquerque, NM

    2005-02-15

    A method for catalytically reducing nitrogen oxide compounds (NO.sub.x, defined as nitric oxide, NO, +nitrogen dioxide, NO.sub.2) in a gas by a material comprising a base metal consisting essentially of CuO and Mn, and oxides of Mn, on an activated metal hydrous metal oxide support, such as HMO:Si. A promoter, such as tungsten oxide or molybdenum oxide, can be added and has been shown to increase conversion efficiency. This method provides good conversion of NO.sub.x to N.sub.2, good selectivity, good durability, resistance to SO.sub.2 aging and low toxicity compared with methods utilizing vanadia-based catalysts.

  20. DUF6 Conversion Facility EIS Schedule

    Science.gov Websites

    and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » Conversion News | FAQs | Internet Resources | Glossary Help | Mailing Services | Contact Us | About Us | Security

  1. Ammonium conversion and its feedback effect on methane oxidation of Methylosinus sporium.

    PubMed

    He, Ruo; Chen, Min; Ma, Ruo-Chan; Su, Yao; Zhang, Xuan

    2017-04-01

    Ammonium (NH 4 + ) is not only nitrogen source that can support methanotrophic growth, but also it can inhibit methane (CH 4 ) oxidation by competing with CH 4 for the active site of methane monooxygenase. NH 4 + conversion and its feedback effect on the growth and activity of methanotrophs were evaluated with Methylosinus sporium used as a model methanotroph. Nitrogen sources could affect the CH 4 -derived carbon distribution, which varied with incubation time and nitrogen concentrations. More CH 4 -derived carbon was incorporated into biomass in the media with NH 4 + -N, compared to nitrate-nitrogen (NO 3 - -N), as sole nitrogen source at the nitrogen concentrations of 10-18 mmol L -1 . Although ammonia (NH 3 ) oxidation activity of methanotrophs was considerably lower, only accounting for 0.01-0.06% of CH 4 oxidation activity in the experimental cultures, NH 4 + conversion could lead to the pH decrease and toxic intermediates accumulation in the their habits. Compared with NH 4 + , nitrite (NO 2 - ) accumulation in the NH 4 + conversion of methanotroph had stronger inhibition on its activity, especially the joint inhibition of NO 2 - accumulation and the pH decrease during the NH 4 + -N conversion. These results suggested that more attention should be paid to the feedback effects of NH 4 + conversion by methanotrophs to understand effects of NH 4 + on CH 4 oxidation in the environments. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  2. Enhanced photocatalytic performance of Er-doped Bi{sub 24}O{sub 31}Br{sub 10}: Facile synthesis and photocatalytic mechanism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Zhang Sheng, E-mail: lzsliu2008@hotmail.com; Liu, Zhi Lin; Liu, Jin Long

    2016-04-15

    Highlights: • Er-doped Bi{sub 24}O{sub 31}Br{sub 10} have been prepared via a one-pot solvothermal method. • Er doping drastically improves the photocatalytic activity of Bi{sub 24}O{sub 31}Br{sub 10}. • The enhanced activity is attributed to effective electron trapping and up-conversion process resulting from Er{sup 3+}. • Holes and super-oxide radicals are main active species. - Abstract: Erbium (Er) doped Bi{sub 24}O{sub 31}Br{sub 10} samples were successfully prepared by using a solvothermal method. The samples were characterized by XRD, XPS, SEM, TEM, BET, DRS, PL and EIS. The photocatalytic activity was evaluated by the degradation of rhodamine B (RhB) and methylmore » orange (MO) under visible light irradiation. The result shows that Er dopant induces a significant improvement in the photocatalytic activity. 1.0% Er–Bi{sub 24}O{sub 31}Br{sub 10} sample exhibits the best photocatalytic performance. The enhanced photocatalytic activity is attributed to the effective trapping of photogenerated electron by Er{sup 3+} ion and the up-conversion process resulting from Er dopant. In addition, it is found that holes and super-oxide radicals play main role in the photocatalytic degradation of RhB and MO.« less

  3. DUF6 EIS Public Comment Form

    Science.gov Websites

    and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » Conversion Uses | DUF6 Management | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet Resources

  4. Electrochemistry of the Zinc-Silver Oxide System. Part 2: Practical Measurements of Energy Conversion Using Commercial Miniature Cells.

    ERIC Educational Resources Information Center

    Smith, Michael J.; Vincent, Colin A.

    1989-01-01

    Summarizes the quantitative relationships pertaining to the operation of electrochemical cells. Energy conversion efficiency, cycle efficiency, battery power, and energy/power density of two types of zinc-silver oxide cells are discussed. (YP)

  5. Regio-selectivity of the Oxidative C-S Bond Formation in Ergothioneine and Ovothiol Biosyntheses

    PubMed Central

    Song, Heng; Leninger, Maureen; Lee, Norman

    2014-01-01

    Ergothioneine (5) and ovothiol (8) are two novel thiol-containing natural products. Their C-S bonds are formed by oxidative coupling reactions catalyzed by EgtB and OvoA enzymes, respectively. In this work, it was discovered that besides catalyzing the oxidative coupling between histidine and cysteine (1 → 6 conversion), OvoA can also catalyze a direct oxidative coupling between hercynine (2) and cysteine (2 → 4 conversion), which can shorten the ergothioneine biosynthetic pathway by two steps. PMID:24016264

  6. Regimes of an atmospheric pressure nanosecond repetitively pulsed discharge for methane partial oxidation

    NASA Astrophysics Data System (ADS)

    Maqueo, P. D. G.; Maier, M.; Evans, M. D. G.; Coulombe, S.; Bergthorson, J. M.

    2018-04-01

    The operation of a nanosecond repetitively pulsed discharge for partial oxidation of CH4 is characterized at atmospheric pressure and room temperature. Two regimes are observed: diffuse and filamentary. The first is a low power regime, characterized by low rotational temperatures around 400 K. The second is much more energetic with rotational temperatures close to 600 K. Both have vibrational temperatures of at least 10 times their rotational temperatures. The average electron number density was determined to be 8.9×1015 and 4.0×1017 cm-3, respectively, showing an increase in the ionization fraction in the more powerful filamentary regime. Results of CH4 conversion to H2, CO, CO2 and C2H6 are presented for the filamentary regime, while the diffuse regime shows no measurable conversion ability. As expected, oxidative mixtures show higher conversion ability than pure CH4. A maximum conversion efficiency of 26.3% and a maximum energy efficiency of 19.7% were reached for the oxidative mixtures.

  7. Finding a Place for Energy: Siting Coal Conversion Facilities. Resource Publications in Geography.

    ERIC Educational Resources Information Center

    Calzonetti, Frank J.; Eckert, Mark S.

    The process of identifying, licensing, and developing energy facility sites for the conversion of coal into more useful forms is the focus of this book, intended for geography students, professors, and researchers. The use of domestic coal resources will ameliorate U.S. dependency on imported fuel. However, because coal is a bulky, dirty fuel…

  8. A Spatial Index for Identifying Opportunity Zones for Woody Cellulosic Conversion Facilities

    Treesearch

    Xia Huang; James H. Perdue; Timothy M. Young

    2012-01-01

    A challenge in the development of renewable energy is the ability to spatially assess the risk of feedstock supply to conversion facilities. Policy makers and investors need improved methods to identify the interactions associated with landscape features, socioeconomic conditions, and ownership patterns, and the influence these variables have on the geographic location...

  9. Novel Combination of Efficient Perovskite Solar Cells with Low Temperature Processed Compact TiO2 Layer via Anodic Oxidation.

    PubMed

    Du, Yangyang; Cai, Hongkun; Wen, Hongbin; Wu, Yuxiang; Huang, Like; Ni, Jian; Li, Juan; Zhang, Jianjun

    2016-05-25

    In this work, a facile and low temperature processed anodic oxidation approach is proposed for fabricating compact and homogeneous titanium dioxide film (AO-TiO2). In order to realize morphology and thickness control of AO-TiO2, the theory concerning anodic oxidation (AO) is unveiled and the influence of relevant parameters during the process of AO such as electrolyte ingredient and oxidation voltage on AO-TiO2 formation is observed as well. Meanwhile, we demonstrate that the planar perovskite solar cells (p-PSCs) fabricated in ambient air and utilizing optimized AO-TiO2 as electron transport layer (ETL) can deliver repeatable power conversion efficiency (PCE) over 13%, which possess superior open-circuit voltage (Voc) and higher fill factor (FF) compared to its counterpart utilizing conventional high temperature processed compact TiO2 (c-TiO2) as ETL. Through a further comparative study, it is indicated that the improvement of device performance should be attributed to more effective electron collection from perovskite layer to AO-TiO2 and the decrease of device series resistance. Furthermore, hysteresis effect about current density-voltage (J-V) curves in TiO2-based p-PSCs is also unveiled.

  10. Tungsten Oxide Nanorods: An Efficient Nanoplatform for Tumor CT Imaging and Photothermal Therapy

    PubMed Central

    Zhou, Zhiguo; Kong, Bin; Yu, Chao; Shi, Xiangyang; Wang, Mingwei; Liu, Wei; Sun, Yanan; Zhang, Yingjian; Yang, Hong; Yang, Shiping

    2014-01-01

    We report here a facile thermal decomposition approach to creating tungsten oxide nanorods (WO2.9 NRs) with a length of 13.1 ± 3.6 nm and a diameter of 4.4 ± 1.5 nm for tumor theranostic applications. The formed WO2.9 NRs were modified with methoxypoly(ethylene glycol) (PEG) carboxyl acid via ligand exchange to have good water dispersability and biocompatibility. With the high photothermal conversion efficiency irradiated by a 980 nm laser and the better X-ray attenuation property than clinically used computed tomography (CT) contrast agent Iohexol, the formed PEGylated WO2.9 NRs are able to inhibit the growth of the model cancer cells in vitro and the corresponding tumor model in vivo, and enable effective CT imaging of the tumor model in vivo. Our “killing two birds with one stone” strategy could be extended for fabricating other nanoplatforms for efficient tumor theranostic applications. PMID:24413483

  11. Who is Responsible for the DUF6 Conversion Facility EISs?

    Science.gov Websites

    project and web site. your e-mail address Sign Me Up Search: OK Button DUF6 Guide DU Uses DUF6 Management U.S. DOE Office of Environmental Management is preparing the two Depleted UF6 Conversion Facility EISs Energy (DOE), Office of Environmental Management (EM) is responsible for preparation of the Depleted UF6

  12. Investigation of Redox Metal Oxides for Carbonaceous Fuel Conversion and CO2 Capture

    NASA Astrophysics Data System (ADS)

    Galinsky, Nathan Lee

    The chemical looping combustion (CLC) process uses metal oxides, also referred to as oxygen carriers, in a redox scheme for conversion of carbonaceous fuels into a concentrated stream of CO2 and steam while also producing heat and electricity. The unique redox scheme of CLC allows CO2 capture with minimal energy penalty. The CLC process performance greatly depends on the oxygen carrier that is chosen. To date, more than 1000 oxygen carriers have been developed for chemical-looping processes using metal oxides containing first-row transition metals. Oxygen carriers are typically mixed with an inert ceramic support to improve their overall mechanical stability and recyclability. This study focuses on design of (i) iron oxide oxygen carriers for conversion of gaseous carbonaceous fuels and (ii) development of perovskite CaMnO 3-d with improved stability and redox properties for conversion of solid fuels. Iron oxide is cheap and environmentally benign. However, it suffers from low activity with carbonaceous fuels due partially to the low ionic conductivity of iron oxides. In order to address the low activity of iron-oxide-based oxygen carriers, support addition has been shown to lower the energy barrier of oxygen anion transport within the oxygen carrier. This work adds a mixed-ionic-and-electronic-conductor (MIEC) support to iron oxide to help facilitate O2- transport inside the lattice of iron oxide. The MIEC-supported iron oxide is compared to commonly used supports including TiO2 and Al2O 3 and the pure ionic conductor support yttria-stabilized zirconia (YSZ) for conversion of different carbonaceous fuels and hydrogen. Results show that the MIEC-supported iron oxide exhibits up to 70 times higher activity than non-MIEC-supported iron oxides for methane conversion. The MIEC supported iron oxide also shows good recyclability with only minor agglomeration and carbon formation observed. The effect of support-iron oxide synergies is further investigated to understand other physical and chemical properties that lead to highly active and recyclable oxygen carriers. Perovskite and fluorite-structured MIEC supports are tested for conversion of methane. The perovskite supported iron oxides exhibit higher activity and stability resulting from the high mixed conductivity of the support. Fluorite-structured CeO2 oxygen carriers deactivated by 75% after 10 redox cycles. This deactivation was attributed to agglomeration of iron oxide. The agglomeration was determined to occur due to Fe x+ transport during the oxidation step leading to high content of Fe on the surface of the oxygen carrier. Besides the MIEC supports, inert MgAl2O4 supported iron oxide is observed to activate in methane. The activation is attributed to carbon formation causing physical degradation of the oxygen carrier and leading to higher surface area and porosity. To achieve high activity with solid fuels, chemical looping with oxygen uncoupling (CLOU) is commonly used. This process uses oxygen carriers with high PO2 that allows the oxygen carrier to release a portion of their lattice oxygen as gaseous oxygen. In turn, the gaseous oxygen can react with solid fuel particles at a higher rate than the lattice oxygen. CaMnO 3 perovskite oxygen carriers offer high potential for CLOU. However, pure CaMnO3 suffers from long-term recyclability and sulfur poisoning. Addition of A-site (Ba and Sr) and B-site (Fe, Ni, Co, Al, and V) dopants are used to improve the performance of the base CaMnO3 oxygen carrier. Sr (A-site) and Fe (B-site) exhibit high compatibility with the base perovskite structure. Both dopants observe oxygen uncoupling properties up to 200°C below that of pure CaMnO3. Additionally, the doped structures also exhibit higher stability at high temperatures (>1000°C) and during redox cycles. The doped oxygen carriers also demonstrate significantly improved activity for coal char conversion.

  13. Study of irradiated Hadfield steel using transmission Mössbauer spectroscopy with high velocity resolution and conversion electron Mössbauer spectroscopy

    NASA Astrophysics Data System (ADS)

    Semionkin, V. A.; Neshev, F. G.; Tsurin, V. A.; Milder, O. B.; Oshtrakh, M. I.

    2010-03-01

    Proton irradiated Hadfield steel foil was studied using transmission Mössbauer spectroscopy with high velocity resolution and conversion electron Mössbauer spectroscopy. It was shown that proton irradiation leads to structural changes in the foil as well as to surface oxidation with ferric hydrous oxide formation (ferrihydrite). Moreover, oxidation on the foil underside was higher than on the foil right side.

  14. Alkane Oxidation: Methane Monooxygenases, Related Enzymes, and Their Biomimetics.

    PubMed

    Wang, Vincent C-C; Maji, Suman; Chen, Peter P-Y; Lee, Hung Kay; Yu, Steve S-F; Chan, Sunney I

    2017-07-12

    Methane monooxygenases (MMOs) mediate the facile conversion of methane into methanol in methanotrophic bacteria with high efficiency under ambient conditions. Because the selective oxidation of methane is extremely challenging, there is considerable interest in understanding how these enzymes carry out this difficult chemistry. The impetus of these efforts is to learn from the microbes to develop a biomimetic catalyst to accomplish the same chemical transformation. Here, we review the progress made over the past two to three decades toward delineating the structures and functions of the catalytic sites in two MMOs: soluble methane monooxygenase (sMMO) and particulate methane monooxygenase (pMMO). sMMO is a water-soluble three-component protein complex consisting of a hydroxylase with a nonheme diiron catalytic site; pMMO is a membrane-bound metalloenzyme with a unique tricopper cluster as the site of hydroxylation. The metal cluster in each of these MMOs harnesses O 2 to functionalize the C-H bond using different chemistry. We highlight some of the common basic principles that they share. Finally, the development of functional models of the catalytic sites of MMOs is described. These efforts have culminated in the first successful biomimetic catalyst capable of efficient methane oxidation without overoxidation at room temperature.

  15. Treatment of high strength distillery wastewater (cherry stillage) by integrated aerobic biological oxidation and ozonation.

    PubMed

    Beltrán, F J; Alvarez, P M; Rodríguez, E M; García-Araya, J F; Rivas, J

    2001-01-01

    The performance of integrated aerobic digestion and ozonation for the treatment of high strength distillery wastewater (i.e., cherry stillage) is reported. Experiments were conducted in laboratory batch systems operating in draw and fill mode. For the biological step, activated sludge from a municipal wastewater treatment facility was used as inoculum, showing a high degree of activity to distillery wastewater. Thus, BOD and COD overall conversions of 95% and 82% were achieved, respectively. However, polyphenol content and absorbance at 254 nm (A(254)) could not be reduced more than 35% and 15%, respectively, by means of single biological oxidation. By considering COD as substrate, the aerobic digestion process followed a Contois' model kinetics, from which the maximum specific growth rate of microorganisms (mu(max)) and the inhibition factor, beta, were then evaluated at different conditions of temperature and pH. In the combined process, the effect of a post-ozonation stage was studied. The main goals achieved by the ozonation step were the removal of polyphenols and A(254). Therefore, ozonation was shown to be an appropriate technology to aid aerobic biological oxidation in the treatment of cherry stillage.

  16. Facile fabrication of hollow mesosphere of crystalline SnO2 nanoparticles and synthesis of SnO2@SWCNTs@Reduced Graphene Oxide nanocomposite as efficient Pt-Free counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Khan, Muhammad Wasim; Yao, Jixin; Zhang, Kang; Zuo, Xueqin; Yang, Qun; Tang, Huaibao; Ur Rehman, Khalid Mehmood; Li, Guang; Wu, Mingzai; Zhu, Kerong; Zhang, Haijun

    2018-06-01

    In this research, SnO2@SWCNTs@Reduced Graphene Oxide based nanocomposite was synthesized by a one step hydrothermal method and reported new cost effective platinum-free counter-electrodes (CEs) in dye-sensitized solar cells (DSSCs). The CEs were formed by using the nanocomposites with the help of a pipette using a doctor-blade technique. The efficiency of this nanocomposite revealed significant elctrocatalytic properties upon falling the triiodide, possessing to synergistic effect of SnO2 nano particles and improved conductivity when SWCNTs dispersed on graphene sheet. Therefore, the power conversion efficiency (PCE) of prepared SnO2@SWCNTs@RGO nanocomposite CE attained of (6.1%) in DSSCs which is equivalent to the value (6.2%) which attained to the value (6.2%) with pure Pt CE as a reference. SnO2@SWCNTs@RGO nanocomposite CEs give more stable catalytic activities for triiodide reduction than SnO2 and SWCNTs CEs in the cyclic voltammetry (CV) analysis. Furthermore, to the subsistence of graphene oxide, the nanocomposite acquired both higher stability and efficiency in the nanocomposite.

  17. Atomic layer epitaxy of hematite on indium tin oxide for application in solar energy conversion

    DOEpatents

    Martinson, Alex B.; Riha, Shannon; Guo, Peijun; Emery, Jonathan D.

    2016-07-12

    A method to provide an article of manufacture of iron oxide on indium tin oxide for solar energy conversion. An atomic layer epitaxy method is used to deposit an uncommon bixbytite-phase iron (III) oxide (.beta.-Fe.sub.2O.sub.3) which is deposited at low temperatures to provide 99% phase pure .beta.-Fe.sub.2O.sub.3 thin films on indium tin oxide. Subsequent annealing produces pure .alpha.-Fe.sub.2O.sub.3 with well-defined epitaxy via a topotactic transition. These highly crystalline films in the ultra thin film limit enable high efficiency photoelectrochemical chemical water splitting.

  18. Thermal conversion of biomass to valuable fuels, chemical feedstocks and chemicals

    DOEpatents

    Peters, William A [Lexington, MA; Howard, Jack B [Winchester, MA; Modestino, Anthony J [Hanson, MA; Vogel, Fredreric [Villigen PSI, CH; Steffin, Carsten R [Herne, DE

    2009-02-24

    A continuous process for the conversion of biomass to form a chemical feedstock is described. The biomass and an exogenous metal oxide, preferably calcium oxide, or metal oxide precursor are continuously fed into a reaction chamber that is operated at a temperature of at least 1400.degree. C. to form reaction products including metal carbide. The metal oxide or metal oxide precursor is capable of forming a hydrolizable metal carbide. The reaction products are quenched to a temperature of 800.degree. C. or less. The resulting metal carbide is separated from the reaction products or, alternatively, when quenched with water, hydolyzed to provide a recoverable hydrocarbon gas feedstock.

  19. Direct conversion of bio-ethanol to isobutene on nanosized Zn(x)Zr(y)O(z) mixed oxides with balanced acid-base sites.

    PubMed

    Sun, Junming; Zhu, Kake; Gao, Feng; Wang, Chongmin; Liu, Jun; Peden, Charles H F; Wang, Yong

    2011-07-27

    We report the design and synthesis of nanosized Zn(x)Zr(y)O(z) mixed oxides for direct and high-yield conversion of bio-ethanol to isobutene (~83%). ZnO is addded to ZrO(2) to selectively passivate zirconia's strong Lewis acidic sites and weaken Brönsted acidic sites, while simultaneously introducing basicity. As a result, the undesired reactions of bio-ethanol dehydration and acetone polymerization/coking are suppressed. Instead, a surface basic site-catalyzed ethanol dehydrogenation to acetaldehyde, acetaldehyde to acetone conversion via a complex pathway including aldol-condensation/dehydrogenation, and a Brönsted acidic site-catalyzed acetone-to-isobutene reaction pathway dominates on the nanosized Zn(x)Zr(y)O(z) mixed oxide catalyst, leading to a highly selective process for direct conversion of bio-ethanol to isobutene.

  20. Hydrogen adsorption on two catalysts for the ortho- to parahydrogen conversion: Cr-doped silica and ferric oxide gel.

    PubMed

    Hartl, Monika; Gillis, Robert Chad; Daemen, Luke; Olds, Daniel P; Page, Katherine; Carlson, Stefan; Cheng, Yongqiang; Hügle, Thomas; Iverson, Erik B; Ramirez-Cuesta, A J; Lee, Yongjoong; Muhrer, Günter

    2016-06-29

    Molecular hydrogen exists in two spin-rotation coupled states: parahydrogen and orthohydrogen. Due to the variation of energy with rotational level, the occupation of ortho- and parahydrogen states is temperature dependent, with parahydrogen being the dominant species at low temperatures. The equilibrium at 20 K (99.8% parahydrogen) can be reached by natural conversion only after a lengthy process. With the use of a suitable catalyst, this process can be shortened significantly. Two types of commercial catalysts currently being used for ortho- to parahydrogen conversion are: iron(iii) oxide (Fe2O3, IONEX®), and chromium(ii) oxide doped silica catalyst (CrO·SiO2, OXISORB®). We investigate the interaction of ortho- and parahydrogen with the surfaces of these ortho-para conversion catalysts using neutron vibrational spectroscopy. The catalytic surfaces have been characterized using X-ray absorption fine structure (XAFS) and X-ray/neutron pair distribution function measurements.

  1. nanostructures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rashad, M. M.; Shalan, A. E.

    2014-08-01

    Hierarchical architectures consisting of one-dimensional (1D) nanostructures are of great interest for potential use in energy and environmental applications in recent years. In this work, hierarchical tungsten oxide (WO3) has been synthesized via a facile hydrothermal route from ammonium metatungstate hydrate and implemented as photoelectrode for dye-sensitized solar cells. The urchin-like WO3 micro-patterns are constructed by self-organized nanoscale length 1D building blocks, which are single crystalline in nature, grown along (001) direction and confirm an orthorhombic crystal phase. The obtained powders were investigated by XRD, SEM, TEM and UV-Vis Spectroscopy. The photovoltaic performance of dye-sensitized solar cells based on WO3 photoanodes was investigated. With increasing the calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency ( η) was increased. The results were attributed to increase the crystallinity of the particles and ease of electron movement. The DSSC based on hierarchical WO3 showed a short-circuit current, an open-circuit voltage, a fill factor, and a conversion efficiency of 4.241 mA/cm2, 0.656 V, 66.74, and 1.85 %, respectively.

  2. Honeycomb-like NiCo2S4 nanosheets prepared by rapid electrodeposition as a counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Yin, Jie; Wang, Yuqiao; Meng, Wenfei; Zhou, Tianyue; Li, Baosong; Wei, Tao; Sun, Yueming

    2017-08-01

    Honeycomb-like nickel cobalt sulfide (NiCo2S4) nanosheets were directly deposited on fluorine-doped tin oxide substrate by a rapid voltammetric deposition method. The method was also controllable and feasible for preparing NiCo2S4 on flexible Ti foil without any heating processes. Compared with Pt, CoS and NiS, NiCo2S4 exhibited low charge-transfer resistances and excellent electrocatalytic activity for {{{{I}}}3}- reduction, acting as a counter electrode for a dye-sensitized solar cell. The NiCo2S4-based solar cell showed higher power conversion efficiency (7.44%) than that of Pt-based solar cell (7.09%) under simulated illumination (AM 1.5 G, 100 mW cm-2). The device based on the flexible NiCo2S4/Ti foil achieved a power conversion efficiency of 5.28% under the above illumination conditions. This work can be extended to flexible and wearable technologies due to its facile technique.

  3. Species Differences in the Oxidative Desulfurization of a Thiouracil-Based Irreversible Myeloperoxidase Inactivator by Flavin-Containing Monooxygenase Enzymes.

    PubMed

    Eng, Heather; Sharma, Raman; Wolford, Angela; Di, Li; Ruggeri, Roger B; Buckbinder, Leonard; Conn, Edward L; Dalvie, Deepak K; Kalgutkar, Amit S

    2016-08-01

    N1-Substituted-6-arylthiouracils, represented by compound 1 [6-(2,4-dimethoxyphenyl)-1-(2-hydroxyethyl)-2-thioxo-2,3-dihydropyrimidin-4(1H)-one], are a novel class of selective irreversible inhibitors of human myeloperoxidase. The present account is a summary of our in vitro studies on the facile oxidative desulfurization in compound 1 to a cyclic ether metabolite M1 [5-(2,4-dimethoxyphenyl)-2,3-dihydro-7H-oxazolo[3,2-a]pyrimidin-7-one] in NADPH-supplemented rats (t1/2 [half-life = mean ± S.D.] = 8.6 ± 0.4 minutes) and dog liver microsomes (t1/2 = 11.2 ± 0.4 minutes), but not in human liver microsomes (t1/2 > 120 minutes). The in vitro metabolic instability also manifested in moderate-to-high plasma clearances of the parent compound in rats and dogs with significant concentrations of M1 detected in circulation. Mild heat deactivation of liver microsomes or coincubation with the flavin-containing monooxygenase (FMO) inhibitor imipramine significantly diminished M1 formation. In contrast, oxidative metabolism of compound 1 to M1 was not inhibited by the pan cytochrome P450 inactivator 1-aminobenzotriazole. Incubations with recombinant FMO isoforms (FMO1, FMO3, and FMO5) revealed that FMO1 principally catalyzed the conversion of compound 1 to M1. FMO1 is not expressed in adult human liver, which rationalizes the species difference in oxidative desulfurization. Oxidation by FMO1 followed Michaelis-Menten kinetics with Michaelis-Menten constant, maximum rate of oxidative desulfurization, and intrinsic clearance values of 209 μM, 20.4 nmol/min/mg protein, and 82.7 μl/min/mg protein, respectively. Addition of excess glutathione essentially eliminated the conversion of compound 1 to M1 in NADPH-supplemented rat and dog liver microsomes, which suggests that the initial FMO1-mediated S-oxygenation of compound 1 yields a sulfenic acid intermediate capable of redox cycling to the parent compound in a glutathione-dependent fashion or undergoing further oxidation to a more electrophilic sulfinic acid species that is trapped intramolecularly by the pendant alcohol motif in compound 1. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  4. Hard templating ultrathin polycrystalline hematite nanosheets: effect of nano-dimension on CO2 to CO conversion via the reverse water-gas shift reaction.

    PubMed

    Fishman, Zachary S; He, Yulian; Yang, Ke R; Lounsbury, Amanda W; Zhu, Junqing; Tran, Thanh Minh; Zimmerman, Julie B; Batista, Victor S; Pfefferle, Lisa D

    2017-09-14

    Understanding how nano-dimensionality impacts iron oxide based catalysis is central to a wide range of applications. Here, we focus on hematite nanosheets, nanowires and nanoparticles as applied to catalyze the reverse water gas shift (RWGS) probe reaction. We introduce a novel approach to synthesize ultrathin (4-7 nm) hematite nanosheets using copper oxide nanosheets as a hard template and propose a reaction mechanism based on density functional theory (DFT) calculations. Hematite nanowires and nanoparticles were also synthesized and characterized. H 2 temperature programmed reduction (H 2 -TPR) and RWGS reactions were performed to glean insights into the mechanism of CO 2 conversion to CO over the iron oxide nanomaterials and were compared to H 2 binding energy calculations based on density functional theory. While the nanosheets did exhibit high CO 2 conversion, 28% at 510 °C, we found that the iron oxide nanowires had the highest CO 2 conversion, reaching 50% at 750 °C under atmospheric pressure. No products besides CO and H 2 O were detected.

  5. Catalytic processes for space station waste conversion

    NASA Technical Reports Server (NTRS)

    Schoonover, M. W.; Madsen, R. A.

    1986-01-01

    Catalytic techniques for processing waste products onboard space vehicles were evaluated. The goal of the study was the conversion of waste to carbon, wash water, oxygen and nitrogen. However, the ultimate goal is conversion to plant nutrients and other materials useful in closure of an ecological life support system for extended planetary missions. The resulting process studied involves hydrolysis at 250 C and 600 psia to break down and compact cellulose material, distillation at 100 C to remove water, coking at 450 C and atmospheric pressure, and catalytic oxidation at 450 to 600 C and atmospheric pressure. Tests were conducted with a model waste to characterize the hydrolysis and coking processes. An oxidizer reactor was sized based on automotive catalytic conversion experience. Products obtained from the hydrolysis and coking steps included a solid residue, gases, water condensate streams, and a volatile coker oil. Based on the data obtained, sufficient component sizing was performed to make a preliminary comparison of the catalytic technique with oxidation for processing waste for a six-man spacecraft. Wet oxidation seems to be the preferred technique from the standpoint of both component simplicity and power consumption.

  6. Optimal siting of solid waste-to-value-added facilities through a GIS-based assessment.

    PubMed

    Khan, Md Mohib-Ul-Haque; Vaezi, Mahdi; Kumar, Amit

    2018-01-01

    Siting a solid waste conversion facility requires an assessment of solid waste availability as well as ensuring compliance with environmental, social, and economic factors. The main idea behind this study was to develop a methodology to locate suitable locations for waste conversion facilities considering waste availability as well as environmental and social constraints. A geographic information system (GIS) spatial analysis was used to identify the most suitable areas and to screen out unsuitable lands. The analytic hierarchy process (AHP) was used for a multi-criteria evaluation of relative preferences of different environmental and social factors. A case study was conducted for Alberta, a western province in Canada, by performing a province-wide waste availability assessment. The total available waste considered in this study was 4,077,514tonnes/year for 19 census divisions collected from 79 landfills. Finally, a location-allocation analysis was performed to determine suitable locations for 10 waste conversion facilities across the province. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Radioactive Waste Management at the New Conversion Facility of 'TVEL'{sup R} Fuel Company - 13474

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Indyk, S.I.; Volodenko, A.V.; Tvilenev, K.A.

    2013-07-01

    The project on the new conversion facility construction is being implemented by Joint Stock Company (JSC) 'Siberian Group of Chemical Enterprises' (SGChE) within TVEL{sup R} Fuel Company. The objective is to construct the up-to-date facility ensuring the industrial and environmental safety with the reduced impact on the community and environment in compliance with the Russian new regulatory framework on radioactive waste (RW) management. The history of the SGChE development, as well as the concepts and approaches to RW management implemented by now are shown. The SGChE future image is outlined, together with its objectives and concept on RW management inmore » compliance with the new act 'On radioactive waste management' adopted in Russia in 2011. Possible areas of cooperation with international companies are discussed in the field of RW management with the purpose of deploying the best Russian and world practices on RW management at the new conversion facility. (authors)« less

  8. 5-hydroxymethylfurfural conversion by fungal aryl-alcohol oxidase and unspecific peroxygenase.

    PubMed

    Carro, Juan; Ferreira, Patricia; Rodríguez, Leonor; Prieto, Alicia; Serrano, Ana; Balcells, Beatriz; Ardá, Ana; Jiménez-Barbero, Jesús; Gutiérrez, Ana; Ullrich, René; Hofrichter, Martin; Martínez, Angel T

    2015-08-01

    Oxidative conversion of 5-hydroxymethylfurfural (HMF) is of biotechnological interest for the production of renewable (lignocellulose-based) platform chemicals, such as 2,5-furandicarboxylic acid (FDCA). To the best of our knowledge, the ability of fungal aryl-alcohol oxidase (AAO) to oxidize HMF is reported here for the first time, resulting in almost complete conversion into 2,5-formylfurancarboxylic acid (FFCA) in a few hours. The reaction starts with alcohol oxidation, yielding 2,5-diformylfuran (DFF), which is rapidly converted into FFCA by carbonyl oxidation, most probably without leaving the enzyme active site. This agrees with the similar catalytic efficiencies of the enzyme with respect to oxidization of HMF and DFF, and its very low activity on 2,5-hydroxymethylfurancarboxylic acid (which was not detected by GC-MS). However, AAO was found to be unable to directly oxidize the carbonyl group in FFCA, and only modest amounts of FDCA are formed from HMF (most probably by chemical oxidation of FFCA by the H2 O2 previously generated by AAO). As aldehyde oxidation by AAO proceeds via the corresponding geminal diols (aldehyde hydrates), the various carbonyl oxidation rates may be related to the low degree of hydration of FFCA compared with DFF. The conversion of HMF was completed by introducing a fungal unspecific heme peroxygenase that uses the H2 O2 generated by AAO to transform FFCA into FDCA, albeit more slowly than the previous AAO reactions. By adding this peroxygenase when FFCA production by AAO has been completed, transformation of HMF into FDCA may be achieved in a reaction cascade in which O2 is the only co-substrate required, and water is the only by-product formed. © 2014 The Authors. FEBS Journal published by John Wiley & Sons Ltd on behalf of FEBS.

  9. Solution combustion synthesis of metal oxide nanomaterials for energy storage and conversion.

    PubMed

    Li, Fa-tang; Ran, Jingrun; Jaroniec, Mietek; Qiao, Shi Zhang

    2015-11-14

    The design and synthesis of metal oxide nanomaterials is one of the key steps for achieving highly efficient energy conversion and storage on an industrial scale. Solution combustion synthesis (SCS) is a time- and energy-saving method as compared with other routes, especially for the preparation of complex oxides which can be easily adapted for scale-up applications. This review summarizes the synthesis of various metal oxide nanomaterials and their applications for energy conversion and storage, including lithium-ion batteries, supercapacitors, hydrogen and methane production, fuel cells and solar cells. In particular, some novel concepts such as reverse support combustion, self-combustion of ionic liquids, and creation of oxygen vacancies are presented. SCS has some unique advantages such as its capability for in situ doping of oxides and construction of heterojunctions. The well-developed porosity and large specific surface area caused by gas evolution during the combustion process endow the resulting materials with exceptional properties. The relationship between the structural properties of the metal oxides studied and their performance is discussed. Finally, the conclusions and perspectives are briefly presented.

  10. Solution combustion synthesis of metal oxide nanomaterials for energy storage and conversion

    NASA Astrophysics Data System (ADS)

    Li, Fa-Tang; Ran, Jingrun; Jaroniec, Mietek; Qiao, Shi Zhang

    2015-10-01

    The design and synthesis of metal oxide nanomaterials is one of the key steps for achieving highly efficient energy conversion and storage on an industrial scale. Solution combustion synthesis (SCS) is a time- and energy-saving method as compared with other routes, especially for the preparation of complex oxides which can be easily adapted for scale-up applications. This review summarizes the synthesis of various metal oxide nanomaterials and their applications for energy conversion and storage, including lithium-ion batteries, supercapacitors, hydrogen and methane production, fuel cells and solar cells. In particular, some novel concepts such as reverse support combustion, self-combustion of ionic liquids, and creation of oxygen vacancies are presented. SCS has some unique advantages such as its capability for in situ doping of oxides and construction of heterojunctions. The well-developed porosity and large specific surface area caused by gas evolution during the combustion process endow the resulting materials with exceptional properties. The relationship between the structural properties of the metal oxides studied and their performance is discussed. Finally, the conclusions and perspectives are briefly presented.

  11. Economic considerations in coverting from oil/gas firing to coal

    NASA Technical Reports Server (NTRS)

    Rau, J. G.

    1978-01-01

    Economic considerations involved in fuel conversion such as from oil and/or gas firing to coal are discussed including investments costs for new facilities and equipment (including air pollution control equipment), operation and maintenance costs, and purchased fuel costs. An analytical approach to assessing the cost effectiveness of fuel conversion in terms of the annual net cost of conversion, the equivalent annual number of barrels of oil saved, and the integral rate of return of the conversion investment is presented. Illustrative numerical examples are presented for typical utility boilers and industrial boiler facilities. A further consideration addressed deals with the impacts of these costs on the overall financial structure of the firm and the ability of the firm to raise the necessary investment captial.

  12. WO3 and W Thermal Atomic Layer Etching Using "Conversion-Fluorination" and "Oxidation-Conversion-Fluorination" Mechanisms.

    PubMed

    Johnson, Nicholas R; George, Steven M

    2017-10-04

    The thermal atomic layer etching (ALE) of WO 3 and W was demonstrated with new "conversion-fluorination" and "oxidation-conversion-fluorination" etching mechanisms. Both of these mechanisms are based on sequential, self-limiting reactions. WO 3 ALE was achieved by a "conversion-fluorination" mechanism using an AB exposure sequence with boron trichloride (BCl 3 ) and hydrogen fluoride (HF). BCl 3 converts the WO 3 surface to a B 2 O 3 layer while forming volatile WO x Cl y products. Subsequently, HF spontaneously etches the B 2 O 3 layer producing volatile BF 3 and H 2 O products. In situ spectroscopic ellipsometry (SE) studies determined that the BCl 3 and HF reactions were self-limiting versus exposure. The WO 3 ALE etch rates increased with temperature from 0.55 Å/cycle at 128 °C to 4.19 Å/cycle at 207 °C. W served as an etch stop because BCl 3 and HF could not etch the underlying W film. W ALE was performed using a three-step "oxidation-conversion-fluorination" mechanism. In this ABC exposure sequence, the W surface is first oxidized to a WO 3 layer using O 2 /O 3 . Subsequently, the WO 3 layer is etched with BCl 3 and HF. SE could simultaneously monitor the W and WO 3 thicknesses and conversion of W to WO 3 . SE measurements showed that the W film thickness decreased linearly with number of ABC reaction cycles. W ALE was shown to be self-limiting with respect to each reaction in the ABC process. The etch rate for W ALE was ∼2.5 Å/cycle at 207 °C. An oxide thickness of ∼20 Å remained after W ALE, but could be removed by sequential BCl 3 and HF exposures without affecting the W layer. These new etching mechanisms will enable the thermal ALE of a variety of additional metal materials including those that have volatile metal fluorides.

  13. Formic-acid-induced depolymerization of oxidized lignin to aromatics

    NASA Astrophysics Data System (ADS)

    Rahimi, Alireza; Ulbrich, Arne; Coon, Joshua J.; Stahl, Shannon S.

    2014-11-01

    Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.

  14. Formic-acid-induced depolymerization of oxidized lignin to aromatics.

    PubMed

    Rahimi, Alireza; Ulbrich, Arne; Coon, Joshua J; Stahl, Shannon S

    2014-11-13

    Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered.

  15. Conversion of ethanol to 1,3-butadiene over Na doped ZnxZryOz mixed metal oxides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baylon, Rebecca A.; Sun, Junming; Wang, Yong

    2016-01-01

    Despite numerous studies on different oxide catalysts for the ethanol to 1,3-butadiene reaction, few have identified active sites (i.e., type of acidity) correlated to the catalytic performances. In this work, the type of acidity needed for ethanol to 1,3-butadiene conversion has been studied over Zn/Zr mixed oxide catalysts. Specifically, synthesis method, Zn/Zr ratio, and Na doping have been used to control the surface acid-base properties, as confirmed by characterizations such as NH3-TPD and IR-Py techniques. The 2000 ppm Na doped Zn1Zr10Oz-H with balanced base and weak Bronsted acid sites was found to give not only high selectivity to 1,3-butadiene (47%)more » at near complete ethanol conversion (97%), but also exhibited a much higher 1,3-butadiene productivity than other mixed oxides studied.« less

  16. 49 CFR 180.513 - Repairs, alterations, conversions, and modifications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Repairs, alterations, conversions, and modifications. 180.513 Section 180.513 Transportation Other Regulations Relating to Transportation (Continued..., alterations, conversions, and modifications. (a) In order to repair tank cars, the tank car facility must...

  17. Fuel Cell/Reformers Technology Development

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA Glenn Research Center is interested in developing Solid Oxide Fuel Cell for use in aerospace applications. Solid oxide fuel cell requires hydrogen rich feed stream by converting commercial aviation jet fuel in a fuel processing process. The grantee's primary research activities center on designing and constructing a test facility for evaluating injector concepts to provide optimum feeds to fuel processor; collecting and analyzing literature information on fuel processing and desulfurization technologies; establishing industry and academic contacts in related areas; providing technical support to in-house SOFC-based system studies. Fuel processing is a chemical reaction process that requires efficient delivery of reactants to reactor beds for optimum performance, i.e., high conversion efficiency and maximum hydrogen production, and reliable continuous operation. Feed delivery and vaporization quality can be improved by applying NASA's expertise in combustor injector design. A 10 KWe injector rig has been designed, procured, and constructed to provide a tool to employ laser diagnostic capability to evaluate various injector concepts for fuel processing reactor feed delivery application. This injector rig facility is now undergoing mechanical and system check-out with an anticipated actual operation in July 2004. Multiple injector concepts including impinging jet, venturi mixing, discrete jet, will be tested and evaluated with actual fuel mixture compatible with reforming catalyst requirement. Research activities from September 2002 to the closing of this collaborative agreement have been in the following areas: compiling literature information on jet fuel reforming; conducting autothermal reforming catalyst screening; establishing contacts with other government agencies for collaborative research in jet fuel reforming and desulfurization; providing process design basis for the build-up of injector rig facility and individual injector design.

  18. Theory of the Spin Galvanic Effect at Oxide Interfaces

    NASA Astrophysics Data System (ADS)

    Seibold, Götz; Caprara, Sergio; Grilli, Marco; Raimondi, Roberto

    2017-12-01

    The spin galvanic effect (SGE) describes the conversion of a nonequilibrium spin polarization into a transverse charge current. Recent experiments have demonstrated a large conversion efficiency for the two-dimensional electron gas formed at the interface between two insulating oxides, LaAlO3 and SrTiO3 . Here, we analyze the SGE for oxide interfaces within a three-band model for the Ti t2 g orbitals which displays an interesting variety of effective spin-orbit couplings in the individual bands that contribute differently to the spin-charge conversion. Our analytical approach is supplemented by a numerical treatment where we also investigate the influence of disorder and temperature, which turns out to be crucial to providing an appropriate description of the experimental data.

  19. Multiphase composition changes and reactive oxygen species formation during limonene oxidation in the new Cambridge Atmospheric Simulation Chamber (CASC)

    NASA Astrophysics Data System (ADS)

    Gallimore, Peter J.; Mahon, Brendan M.; Wragg, Francis P. H.; Fuller, Stephen J.; Giorio, Chiara; Kourtchev, Ivan; Kalberer, Markus

    2017-08-01

    The chemical composition of organic aerosols influences their impacts on human health and the climate system. Aerosol formation from gas-to-particle conversion and in-particle reaction was studied for the oxidation of limonene in a new facility, the Cambridge Atmospheric Simulation Chamber (CASC). Health-relevant oxidising organic species produced during secondary organic aerosol (SOA) formation were quantified in real time using an Online Particle-bound Reactive Oxygen Species Instrument (OPROSI). Two categories of reactive oxygen species (ROS) were identified based on time series analysis: a short-lived component produced during precursor ozonolysis with a lifetime of the order of minutes, and a stable component that was long-lived on the experiment timescale (˜ 4 h). Individual organic species were monitored continuously over this time using Extractive Electrospray Ionisation (EESI) Mass Spectrometry (MS) for the particle phase and Proton Transfer Reaction (PTR) MS for the gas phase. Many first-generation oxidation products are unsaturated, and we observed multiphase aging via further ozonolysis reactions. Volatile products such as C9H14O (limonaketone) and C10H16O2 (limonaldehyde) were observed in the gas phase early in the experiment, before reacting again with ozone. Loss of C10H16O4 (7-hydroxy limononic acid) from the particle phase was surprisingly slow. A combination of reduced C = C reactivity and viscous particle formation (relative to other SOA systems) may explain this, and both scenarios were tested in the Pretty Good Aerosol Model (PG-AM). A range of characterisation measurements were also carried out to benchmark the chamber against existing facilities. This work demonstrates the utility of CASC, particularly for understanding the reactivity and health-relevant properties of organic aerosols using novel, highly time-resolved techniques.

  20. Chemical interaction matrix between reagents in a Purex based process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brahman, R.K.; Hennessy, W.P.; Paviet-Hartmann, P.

    2008-07-01

    The United States Department of Energy (DOE) is the responsible entity for the disposal of the United States excess weapons grade plutonium. DOE selected a PUREX-based process to convert plutonium to low-enriched mixed oxide fuel for use in commercial nuclear power plants. To initiate this process in the United States, a Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF) is under construction and will be operated by Shaw AREVA MOX Services at the Savannah River Site. This facility will be licensed and regulated by the U.S. Nuclear Regulatory Commission (NRC). A PUREX process, similar to the one used at La Hague,more » France, will purify plutonium feedstock through solvent extraction. MFFF employs two major process operations to manufacture MOX fuel assemblies: (1) the Aqueous Polishing (AP) process to remove gallium and other impurities from plutonium feedstock and (2) the MOX fuel fabrication process (MP), which processes the oxides into pellets and manufactures the MOX fuel assemblies. The AP process consists of three major steps, dissolution, purification, and conversion, and is the center of the primary chemical processing. A study of process hazards controls has been initiated that will provide knowledge and protection against the chemical risks associated from mixing of reagents over the life time of the process. This paper presents a comprehensive chemical interaction matrix evaluation for the reagents used in the PUREX-based process. Chemical interaction matrix supplements the process conditions by providing a checklist of any potential inadvertent chemical reactions that may take place. It also identifies the chemical compatibility/incompatibility of the reagents if mixed by failure of operations or equipment within the process itself or mixed inadvertently by a technician in the laboratories. (aut0010ho.« less

  1. Atomically monodisperse nickel nanoclusters as highly active electrocatalysts for water oxidation

    NASA Astrophysics Data System (ADS)

    Joya, Khurram S.; Sinatra, Lutfan; Abdulhalim, Lina G.; Joshi, Chakra P.; Hedhili, M. N.; Bakr, Osman M.; Hussain, Irshad

    2016-05-01

    Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these Ni NCs are found to be Ni4(PET)8 and Ni6(PET)12 and are highly active electrocatalysts for oxygen evolution without any pre-conditioning. Ni4(PET)8 are slightly better catalysts than Ni6(PET)12 which initiate oxygen evolution at an amazingly low overpotential of ~1.51 V (vs. RHE; η ~ 280 mV). The peak oxygen evolution current density (J) of ~150 mA cm-2 at 2.0 V (vs. RHE) with a Tafel slope of 38 mV dec-1 is observed using Ni4(PET)8. These results are comparable to the state-of-the-art RuO2 electrocatalyst, which is highly expensive and rare compared to Ni-based materials. Sustained oxygen generation for several hours with an applied current density of 20 mA cm-2 demonstrates the long-term stability and activity of these Ni NCs towards electrocatalytic water oxidation. This unique approach provides a facile method to prepare cost-effective, nanoscale and highly efficient electrocatalysts for water oxidation.Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these Ni NCs are found to be Ni4(PET)8 and Ni6(PET)12 and are highly active electrocatalysts for oxygen evolution without any pre-conditioning. Ni4(PET)8 are slightly better catalysts than Ni6(PET)12 which initiate oxygen evolution at an amazingly low overpotential of ~1.51 V (vs. RHE; η ~ 280 mV). The peak oxygen evolution current density (J) of ~150 mA cm-2 at 2.0 V (vs. RHE) with a Tafel slope of 38 mV dec-1 is observed using Ni4(PET)8. These results are comparable to the state-of-the-art RuO2 electrocatalyst, which is highly expensive and rare compared to Ni-based materials. Sustained oxygen generation for several hours with an applied current density of 20 mA cm-2 demonstrates the long-term stability and activity of these Ni NCs towards electrocatalytic water oxidation. This unique approach provides a facile method to prepare cost-effective, nanoscale and highly efficient electrocatalysts for water oxidation. Electronic supplementary information (ESI) available: CCDC 1419754 and 1419731. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6nr00709k

  2. Effect of Ce2O3, La2O3 and ZnO additives on the oxygenates conversion into liquid hydrocarbons

    NASA Astrophysics Data System (ADS)

    Kachalov, V. V.; Lavrenov, V. A.; Lishchiner, I. I.; Malova, O. V.; Tarasov, A. L.; Zaichenko, V. M.

    2018-01-01

    A selective modifying effect of cerium, magnesium and zinc oxide additives on the activity and the selectivity of a pentasil group zeolite catalyst in the reaction of conversion of oxygenates (methanol and dimethyl ether) to liquid hydrocarbons was found. It was found that zinc oxide contributes to the stable operation of the zeolite catalyst in the conversion of oxygenates in the synthesis gas stream and leads to the production of gasolines with low durene content (not more than 6.1 wt%). The obtained results demonstrate the rationale for producing hydrocarbons from synthesis gas without the stage of oxygenate separation with their subsequent conversion to synthetic gasoline.

  3. News and Events

    Science.gov Websites

    Conversion EIS Documents News FAQs Internet Resources Glossary Home » News News & Events line line | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet Resources | Glossary Help | Mailing

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Ying; Lee, Sungsik; Brown, Dennis E.

    Ultrafine manganese oxide-decorated carbon nanofibers (MnOn-CNF) as a new type of electrode materials are facilely fabricated by direct conversion of Mn, Zn-trimesic acid (H3BTC) metal organic framework fibers (Mn-ZnBTC). The construction and evolution of Mn-ZnBTC precursors are investigated by SEM and in situ high-energy XRD. The manganese oxides are highly dispersed onto the porous carbon nanofibers formed simultaneously, verified by TEM, X-ray absorption fine structure (XAFS), Raman, ICP-AES and N2 adsorption techniques. As expected, the resulting MnOn-CNF composites are highly stable, and can be cycled up to 5000 times with a high capacitance retention ratio of 98% in electrochemical capacitormore » measurements. They show a high capacitance of up to 179 F g–1 per mass of the composite electrode, and a remarkable capacitance of up to 18290 F g–1 per active mass of the manganese(IV) oxide, significantly exceeding the theoretical specific capacitance of manganese(IV) oxide (1370 F g–1). The maximum energy density is up to 19.7 Wh kg–1 at the current density of 0.25 A g–1, even orders higher than those of reported electric double-layer capacitors and pseudocapacitors. The excellent capacitive performance can be ascribed to the joint effect of easy accessibility, high porosity, tight contact and superior conductivity integrated in final MnOn-CNF composites.« less

  5. Radical-driven carbonyl-to-acid conversion and acid degradation in tropospheric aqueous systems studied by CAPRAM

    NASA Astrophysics Data System (ADS)

    Tilgner, A.; Herrmann, H.

    2010-12-01

    Model studies on the aqueous phase radical-driven processing of carbonyl compounds and acids in clouds and deliquescent particles were performed. The model exposed that aqueous radical conversions of carbonyl compounds and its oxidation products can contribute potentially to the formation of functionalised organic acids. The main identified C 2-C 4 organic gas phase precursors are ethylene glycol, glycolaldehyde, glyoxal, methylglyoxal and 1,4-butenedial. The aqueous phase is shown to contribute significantly with about 93%/63%, 47%/8%, 31%/4%, 7%/4%, 36%/8% to the multiphase oxidative fate of these compounds under remote/urban conditions. Interestingly, the studies revealed that aqueous chemical processing is not only limited to in-cloud conditions but also proceeds in deliquescent particle phase with significant fluxes. Oxalic acid is shown to be formed preferably in deliquescent particles subsequent to the in-cloud oxidations. Mean aqueous phase oxalate formation fluxes of about 12, 42 and 0.4 ng m -3 h -1 in the remote, urban and maritime scenario, respectively. Additionally, the turnovers of the oxidation of organics such as methylglyoxal by NO 3 radical reactions are identified to be competitive to their OH pendants. At the current state of CAPRAM, mean C 2-C 4 in-cloud oxidation fluxes of about 0.12 and 0.5 μg m -3 h -1 are modelled under the idealised remote and urban cloud conditions. Finally, turnovers from radical oxidations were compared with those of thermal reactions. It is demonstrated that, based on the sparse kinetic data available organic accretion reaction might be of interest in just a few cases for cloud droplets and aqueous particles but generally do not reach the oxidative conversion rates of the main radical oxidants OH and NO 3. Interestingly, oxidation reactions of H 2O 2 are shown to be competitive to the OH radical conversions in cases when H 2O 2 is not readily used up by the S(IV) oxidation.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warren, B.K.; Campbell, K.D.

    Methane oxidative coupling studies were carried out in an atmospheric quartz reactor at temperatures between 700 and 800/degree/C. New catalysts prepared and studied included doped alkaline earth catalysts, lanthanide oxides, and proprietary catalysts. Neodymium oxide, Nd/sub 2/O/sub 3/, was found to be as active and selective as samarium oxide, Sm/sub 2/O/sub 3/, in contrast to literature reports. Proprietary Union Carbide catalysts (UCC-S:1) showed initial methane conversions and C/sub 2/ selectivities comparable to literature catalysts. Atypically low carbon dioxide to carbon monoxide ratios (typically ten times lower than those seen in the literature or other catalysts tested) and high ethylene tomore » ethane ratios (3 to 6 compared to typical literature ratios below 1) were obtained. These results are interesting because ethylene is more valuable than ethane and carbon monoxide is more valuable than carbon dioxide. With these UCC-S:1 catalysts, rapid deactivation was coupled with an observed shift in product ratios toward those more typical in the literature. Initial cases for process conceptualization studies were selected. The Comparison Case will consist of the conversion sequence from methane to synthesis gas to methanol to olefins to liquid hydrocarbon fuels. Case 1 will consist of the conversion of methane to ethylene and ethane. Case 2 will be the direct conversion of methane to C/sub 2/'s followed by conversion to liquid hydrocarbon fuels. 7 figs., 18 tabs.« less

  7. Mailing Services

    Science.gov Websites

    DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home  | DUF6 Management | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet Resources | Glossary

  8. Why Are the DUF6 Conversion Facility EISs Needed?

    Science.gov Websites

    Depleted UF6 Conversion EISs are needed to assess the potential environmental impacts of constructing the potential environmental impacts of constructing, operating, maintaining, and decontaminating and ; alternative. The EISs will aid decision making on DUF6 conversion by evaluating the environmental impacts of

  9. Highly efficient Cu-decorated iron oxide nanocatalyst for low pressure CO 2 conversion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Halder, Avik; Kilianová, Martina; Yang, Bing

    We report a nanoparticulate iron oxide based catalyst for CO2 conversion with high efficiency at low pressures and on the effect of the presence of copper on the catalyst's restructuring and its catalytic performance. In situ X-ray scattering reveals the restructuring of the catalyst at the nanometer scale. In situ X-ray absorption near edge structure (XANES) shows the evolution of the composition and oxidation state of the iron and copper components under reaction conditions along with the promotional effect of copper on the chemical transformation of the iron component. X-ray diffraction (XRD), XANES and Raman spectroscopy proved that the startingmore » nano catalyst is composed of iron oxides differing in chemical nature (alpha-Fe2O3, Fe3O4, FeO(OH)) and dimensionality, while the catalyst after CO2 conversion was identified as a mixture of alpha-Fe, Fe3C, and traces of Fe5C2. The significant increase of the rate CO2 is turned over in the presence of copper nanoparticles indicates that Cu nanoparticles activate hydrogen, which after spilling over to the neighbouring iron sites, facilitate a more efficient conversion of carbon dioxide.« less

  10. Development of evaluation models of manpower needs for dismantling the dry conversion process-related equipment in uranium refining and conversion plant (URCP)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sari Izumo; Hideo Usui; Mitsuo Tachibana

    Evaluation models for determining the manpower needs for dismantling various types of equipment in uranium refining and conversion plant (URCP) have been developed. The models are widely applicable to other uranium handling facilities. Additionally, a simplified model was developed for easily and accurately calculating the manpower needs for dismantling dry conversion process-related equipment (DP equipment). It is important to evaluate beforehand project management data such as manpower needs to prepare an optimized decommissioning plan and implement effective dismantling activity. The Japan Atomic Energy Agency (JAEA) has developed the project management data evaluation system for dismantling activities (PRODIA code), which canmore » generate project management data using evaluation models. For preparing an optimized decommissioning plan, these evaluation models should be established based on the type of nuclear facility and actual dismantling data. In URCP, the dry conversion process of reprocessed uranium and others was operated until 1999, and the equipment related to the main process was dismantled from 2008 to 2011. Actual data such as manpower for dismantling were collected during the dismantling activities, and evaluation models were developed using the collected actual data on the basis of equipment classification considering the characteristics of uranium handling facility. (authors)« less

  11. Role of Peroxidase in Lignification of Tobacco Cells 1

    PubMed Central

    Mäder, Michael; Füssl, Resi

    1982-01-01

    Coniferyl alcohol is the primary substrate for peroxidase-mediated lignification, a process which depends on the generation of H2O2 by NADH oxidation. We measured the concentrations of various phenols (synthetic and natural) at which maximal enhancement of NADH oxidation occurs. Coniferyl alcohol was found to stimulate NADH oxidation at a much lower concentration (0.01 mm) than other natural or synthetic phenols (1-100 mm). In addition, coniferyl alcohol prevented the conversion of active peroxidase into the inactive intermediate compound III—which is usually formed in the presence of NADH—at equally low concentrations. This conversion was found to be a prerequisite for stimulation of NADH-oxidation, but it was not necessarily connected to stimulation. The oxidation of NADH and coniferyl alcohol (or guaiacol) can occur simultaneously, but there is a strong competitive interaction between these two substrates. At pH 5, the presence of NADH at concentrations 30 to 60 times lower than the phenols completely prevents their oxidation. The results are discussed in relation to the role of cell wall peroxidases in conversion of coniferyl alcohol to lignin and in formation of H2O2. PMID:16662627

  12. Modularized Production of Value-Added Products and Fuels from Distributed Waste Carbon-Rich Feedstocks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weber, Robert S.; Holladay, Johnathan E.

    Here, we have adapted and characterized electrolysis reactors to complement the conversion of regional- and community-scale quantities of waste into fuel or chemicals. The overall process must be able to contend with a wide range of feedstocks, must be inherently safe, and should not rely on external facilities for co-reactants or heat rejection and supply. Our current approach is based on the upgrading of bio-oil produced by the hydrothermal liquefaction (HTL) of carbon-containing waste feedstocks. HTL can convert a variety of feedstocks into a bio-oil that requires much less upgrading than the products of other ways of deconstructing biomass. Wemore » are now investigating the use of electrochemical processes for the further conversions needed to transform the bio-oil from HTL into fuel or higher value chemicals. We, and others, have shown that electrochemical reduction can offer adequate reaction rates and at least some of the necessary generality. In addition, an electrochemical reactor necessarily both oxidizes (removes electrons) on one side of the reactor and reduces (adds electrons) on the other side. Therefore, the two types of reactions could, in principle, be coupled to upgrade the bio-oil and simultaneously polish the water that is employed as a reactant and a carrier in the upstream HTL. Here, we overview a notional process, the possible conversion chemistry, and the economics of an HTL-electrochemical process.« less

  13. Modularized Production of Value-Added Products and Fuels from Distributed Waste Carbon-Rich Feedstocks

    DOE PAGES

    Weber, Robert S.; Holladay, Johnathan E.

    2018-05-22

    Here, we have adapted and characterized electrolysis reactors to complement the conversion of regional- and community-scale quantities of waste into fuel or chemicals. The overall process must be able to contend with a wide range of feedstocks, must be inherently safe, and should not rely on external facilities for co-reactants or heat rejection and supply. Our current approach is based on the upgrading of bio-oil produced by the hydrothermal liquefaction (HTL) of carbon-containing waste feedstocks. HTL can convert a variety of feedstocks into a bio-oil that requires much less upgrading than the products of other ways of deconstructing biomass. Wemore » are now investigating the use of electrochemical processes for the further conversions needed to transform the bio-oil from HTL into fuel or higher value chemicals. We, and others, have shown that electrochemical reduction can offer adequate reaction rates and at least some of the necessary generality. In addition, an electrochemical reactor necessarily both oxidizes (removes electrons) on one side of the reactor and reduces (adds electrons) on the other side. Therefore, the two types of reactions could, in principle, be coupled to upgrade the bio-oil and simultaneously polish the water that is employed as a reactant and a carrier in the upstream HTL. Here, we overview a notional process, the possible conversion chemistry, and the economics of an HTL-electrochemical process.« less

  14. Tantalum Sulfide Nanosheets as a Theranostic Nanoplatform for Computed Tomography Imaging-Guided Combinatorial Chemo-Photothermal Therapy.

    PubMed

    Liu, Yanlan; Ji, Xiaoyuan; Liu, Jianhua; Tong, Winnie W L; Askhatova, Diana; Shi, Jinjun

    2017-10-19

    Near-infrared (NIR)-absorbing metal-based nanomaterials have shown tremendous potential for cancer therapy, given their facile and controllable synthesis, efficient photothermal conversion, capability of spatiotemporal-controlled drug delivery, and intrinsic imaging function. Tantalum (Ta) is among the most biocompatible metals and arouses negligible adverse biological responses in either oxidized or reduced forms, and thus Ta-derived nanomaterials represent promising candidates for biomedical applications. However, Ta-based nanomaterials by themselves have not been explored for NIR-mediated photothermal ablation therapy. In this work, we report an innovative Ta-based multifunctional nanoplatform composed of biocompatible tantalum sulfide (TaS 2 ) nanosheets (NSs) for simultaneous NIR hyperthermia, drug delivery, and computed tomography (CT) imaging. The TaS 2 NSs exhibit multiple unique features including (i) efficient NIR light-to-heat conversion with a high photothermal conversion efficiency of 39%. (ii) high drug loading (177% by weight), (iii) controlled drug release triggered by NIR light and moderate acidic pH, (iv) high tumor accumulation via heat-enhanced tumor vascular permeability, (v) complete tumor ablation and negligible side effects, and (vi) comparable CT imaging contrast efficiency to the widely clinically used agent iobitridol. We expect that this multifunctional NS platform can serve as a promising candidate for imaging-guided cancer therapy and selection of cancer patients with high tumor accumulation.

  15. Moon base reactor system

    NASA Technical Reports Server (NTRS)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  16. Inheritance of Crystallographic Orientation during Lithiation/Delithiation Processes of Single-Crystal α-Fe2O3 Nanocubes in Lithium-Ion Batteries.

    PubMed

    Ma, Xiaowei; Zhang, Manyu; Liang, Chongyun; Li, Yuesheng; Wu, Jingjing; Che, Renchao

    2015-11-04

    Iron oxides are very promising anode materials based on conversion reactions for lithium-ion batteries (LIBs). During conversion processes, the crystal structure and composition of the electrode material are drastically changed. Surprisingly, in our study, inheritance of a crystallographic orientation was found during lithiation/delithiation processes of single-crystal α-Fe2O3 nanocubes by ex situ transmission electron microscopy. Single-crystal α-Fe2O3 was first transformed into numerous Fe nanograins embedded in a Li2O matrix, and then the conversion between Fe and FeO nanograins became the main reversible electrochemical reaction for energy storage. Interestingly, these Fe/FeO nanograins had almost the same crystallographic orientation, indicating that the lithiated/delithiated products can inherit the crystallographic orientation of single-crystal α-Fe2O3. This finding is important for understanding the detailed electrochemical conversion processes of iron oxides, and this feature may also exist during lithiation/delithiation processes of other transition-metal oxides.

  17. Validation of gamma-ray detection techniques for safeguards monitoring at natural uranium conversion facilities

    NASA Astrophysics Data System (ADS)

    Dewji, S. A.; Lee, D. L.; Croft, S.; Hertel, N. E.; Chapman, J. A.; McElroy, R. D.; Cleveland, S.

    2016-07-01

    Recent IAEA circulars and policy papers have sought to implement safeguards when any purified aqueous uranium solution or uranium oxides suitable for isotopic enrichment or fuel fabrication exists. Under the revised policy, IAEA Policy Paper 18, the starting point for nuclear material under safeguards was reinterpreted, suggesting that purified uranium compounds should be subject to safeguards procedures no later than the first point in the conversion process. In response to this technical need, a combination of simulation models and experimental measurements were employed to develop and validate concepts of nondestructive assay monitoring systems in a natural uranium conversion plant (NUCP). In particular, uranyl nitrate (UO2(NO3)2) solution exiting solvent extraction was identified as a key measurement point (KMP), where gamma-ray spectroscopy was selected as the process monitoring tool. The Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility at Oak Ridge National Laboratory was employed to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in an NUCP. Nondestructive assay techniques using gamma-ray spectroscopy were evaluated to determine their viability as a technical means for drawing safeguards conclusions at NUCPs, and if the IAEA detection requirements of 1 significant quantity (SQ) can be met in a timely way. This work investigated gamma-ray signatures of uranyl nitrate circulating in the UNCLE facility and evaluated various gamma-ray detector sensitivities to uranyl nitrate. These detector validation activities include assessing detector responses to the uranyl nitrate gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and high-purity germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10-90 g U/L of natural uranyl nitrate are presented. A range of gamma-ray lines is examined, including attenuation for transmission measurement of density and concentration. It was determined that transmission-corrected gamma-ray spectra provide a reliable way to monitor the 235U concentration of uranyl nitrate solution in transfer pipes in NUCPs. Furthermore, existing predictive and analysis methods are adequate to design and realize practical designs. The 137Cs transmission source employed in this work is viable but not optimal for 235U densitometry determination. Validated simulations assessed the viability of 133Ba and 57Co as alternative densitometry sources. All three gamma-ray detectors are viable for monitoring natural uranium feed; although high-purity germanium is easiest to interpret, it is, however, the least attractive as an installation instrument. Overall, for monitoring throughput in a facility such as UNCLE, emulating the uranium concentration and pump speeds of the Springfields conversion facility in the United Kingdom, an uncertainty of less than 0.17% is required in order to detect the diversion of 1 SQ of uranyl nitrate through changes in uranium concentration over an accountancy period of one year with a detection probability of 50%. Although calibrated gamma-ray detection systems are capable of determining the concentration of uranium content in NUCPs, it is only in combination with verifiable operator declarations and supporting data, such as flow rate and enrichment, that safeguards conclusions can be drawn.

  18. Selective Aerobic Oxidation of 5-(Hydroxymethyl)furfural to 5-Formyl-2-furancarboxylic Acid in Water.

    PubMed

    Ventura, Maria; Aresta, Michele; Dibenedetto, Angela

    2016-05-23

    A simple, cheap, and selective catalyst based on copper/cerium oxides is described for the oxidation of 5-(hydroxymethyl)furfural (5-HMF) in water. An almost quantitative conversion (99 %) with excellent (90 %) selectivity towards the formation of 5-formyl-2-furancarboxylic acid, a platform molecule for other high value chemicals, is observed. The catalyst does not require any pretreatment or additives, such as bases, to obtain high yield and selectivity in water as solvent and using oxygen as oxidant. When a physical mixture of the oxides is used, low conversion and selectivity are observed. Air can be used instead of oxygen, but a lower conversion rate is observed if the same overall pressure is used, and the selectivity remains high. The catalyst can be recovered almost quantitatively and reused. Deactivation of the catalyst, observed in repeated runs, is due to the deposition of humins on its surface. Upon calcination the catalyst almost completely recovers its activity and selectivity, proving that the catalyst is robust. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Photo-switchable two-dimensional nanofluidic ionic diodes.

    PubMed

    Wang, Lili; Feng, Yaping; Zhou, Yi; Jia, Meijuan; Wang, Guojie; Guo, Wei; Jiang, Lei

    2017-06-01

    The bottom-up assembly of ion-channel-mimetic nanofluidic devices and materials with two-dimensional (2D) nano-building blocks paves a straightforward way towards the real-world applications of the novel transport phenomena on a nano- or sub-nanoscale. One immediate challenge is to provide the 2D nanofluidic systems with adaptive responsibilities and asymmetric ion transport characteristics. Herein, we introduce a facile and general strategy to provide a graphene-oxide-based 2D nanofluidic system with photo-switchable ionic current rectification (ICR). The degree of ICR can be prominently enhanced upon UV irradiation and it can be perfectly retrieved under irradiation with visible light. A maximum ICR ratio of about 48 was achieved. The smart and functional nanofluidic devices have applications in energy conversion, chemical sensing, water treatment, etc .

  20. 40 CFR Table 2 to Subpart Fff of... - Nitrogen Oxides Requirements for Affected Facilities

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 8 2011-07-01 2011-07-01 false Nitrogen Oxides Requirements for... Before September 20, 1994 Pt. 62, Subpt. FFF, Table 2 Table 2 to Subpart FFF of Part 62—Nitrogen Oxides Requirements for Affected Facilities Municipal waste combustor technology Nitrogen oxides emission limit (parts...

  1. 40 CFR Table 1 to Subpart Cb of... - Nitrogen Oxides Guidelines for Designated Facilities

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Nitrogen Oxides Guidelines for... September 20, 1994 Pt. 60, Subpt. Cb, Table 1 Table 1 to Subpart Cb of part 60—Nitrogen Oxides Guidelines for Designated Facilities Municipal waste combustor technology Before April 28, 2009,nitrogen oxides...

  2. 40 CFR Table 2 to Subpart Fff of... - Nitrogen Oxides Requirements for Affected Facilities

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Nitrogen Oxides Requirements for... Before September 20, 1994 Pt. 62, Subpt. FFF, Table 2 Table 2 to Subpart FFF of Part 62—Nitrogen Oxides Requirements for Affected Facilities Municipal waste combustor technology Nitrogen oxides emission limit (parts...

  3. 40 CFR Table 2 to Subpart Fff of... - Nitrogen Oxides Requirements for Affected Facilities

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Nitrogen Oxides Requirements for... Before September 20, 1994 Pt. 62, Subpt. FFF, Table 2 Table 2 to Subpart FFF of Part 62—Nitrogen Oxides Requirements for Affected Facilities Municipal waste combustor technology Nitrogen oxides emission limit (parts...

  4. 40 CFR Table 2 to Subpart Fff of... - Nitrogen Oxides Requirements for Affected Facilities

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Nitrogen Oxides Requirements for... Before September 20, 1994 Pt. 62, Subpt. FFF, Table 2 Table 2 to Subpart FFF of Part 62—Nitrogen Oxides Requirements for Affected Facilities Municipal waste combustor technology Nitrogen oxides emission limit (parts...

  5. 40 CFR Table 1 to Subpart Cb of... - Nitrogen Oxides Guidelines for Designated Facilities

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Nitrogen Oxides Guidelines for... September 20, 1994 Pt. 60, Subpt. Cb, Table 1 Table 1 to Subpart Cb of Part 60—Nitrogen Oxides Guidelines for Designated Facilities Municipal waste combustor technology Before April 28, 2009,nitrogen oxides...

  6. Structural basis for binding of fluorinated glucose and galactose to Trametes multicolor pyranose 2-oxidase variants with improved galactose conversion.

    PubMed

    Tan, Tien Chye; Spadiut, Oliver; Gandini, Rosaria; Haltrich, Dietmar; Divne, Christina

    2014-01-01

    Each year, about six million tons of lactose are generated from liquid whey as industrial byproduct, and optimally this large carbohydrate waste should be used for the production of value-added products. Trametes multicolor pyranose 2-oxidase (TmP2O) catalyzes the oxidation of various monosaccharides to the corresponding 2-keto sugars. Thus, a potential use of TmP2O is to convert the products from lactose hydrolysis, D-glucose and D-galactose, to more valuable products such as tagatose. Oxidation of glucose is however strongly favored over galactose, and oxidation of both substrates at more equal rates is desirable. Characterization of TmP2O variants (H450G, V546C, H450G/V546C) with improved D-galactose conversion has been given earlier, of which H450G displayed the best relative conversion between the substrates. To rationalize the changes in conversion rates, we have analyzed high-resolution crystal structures of the aforementioned mutants with bound 2- and 3-fluorinated glucose and galactose. Binding of glucose and galactose in the productive 2-oxidation binding mode is nearly identical in all mutants, suggesting that this binding mode is essentially unaffected by the mutations. For the competing glucose binding mode, enzyme variants carrying the H450G replacement stabilize glucose as the α-anomer in position for 3-oxidation. The backbone relaxation at position 450 allows the substrate-binding loop to fold tightly around the ligand. V546C however stabilize glucose as the β-anomer using an open loop conformation. Improved binding of galactose is enabled by subtle relaxation effects at key active-site backbone positions. The competing binding mode for galactose 2-oxidation by V546C stabilizes the β-anomer for oxidation at C1, whereas H450G variants stabilize the 3-oxidation binding mode of the galactose α-anomer. The present study provides a detailed description of binding modes that rationalize changes in the relative conversion rates of D-glucose and D-galactose and can be used to refine future enzyme designs for more efficient use of lactose-hydrolysis byproducts.

  7. Structural Basis for Binding of Fluorinated Glucose and Galactose to Trametes multicolor Pyranose 2-Oxidase Variants with Improved Galactose Conversion

    PubMed Central

    Gandini, Rosaria; Haltrich, Dietmar; Divne, Christina

    2014-01-01

    Each year, about six million tons of lactose are generated from liquid whey as industrial byproduct, and optimally this large carbohydrate waste should be used for the production of value-added products. Trametes multicolor pyranose 2-oxidase (TmP2O) catalyzes the oxidation of various monosaccharides to the corresponding 2-keto sugars. Thus, a potential use of TmP2O is to convert the products from lactose hydrolysis, D-glucose and D-galactose, to more valuable products such as tagatose. Oxidation of glucose is however strongly favored over galactose, and oxidation of both substrates at more equal rates is desirable. Characterization of TmP2O variants (H450G, V546C, H450G/V546C) with improved D-galactose conversion has been given earlier, of which H450G displayed the best relative conversion between the substrates. To rationalize the changes in conversion rates, we have analyzed high-resolution crystal structures of the aforementioned mutants with bound 2- and 3-fluorinated glucose and galactose. Binding of glucose and galactose in the productive 2-oxidation binding mode is nearly identical in all mutants, suggesting that this binding mode is essentially unaffected by the mutations. For the competing glucose binding mode, enzyme variants carrying the H450G replacement stabilize glucose as the α-anomer in position for 3-oxidation. The backbone relaxation at position 450 allows the substrate-binding loop to fold tightly around the ligand. V546C however stabilize glucose as the β-anomer using an open loop conformation. Improved binding of galactose is enabled by subtle relaxation effects at key active-site backbone positions. The competing binding mode for galactose 2-oxidation by V546C stabilizes the β-anomer for oxidation at C1, whereas H450G variants stabilize the 3-oxidation binding mode of the galactose α-anomer. The present study provides a detailed description of binding modes that rationalize changes in the relative conversion rates of D-glucose and D-galactose and can be used to refine future enzyme designs for more efficient use of lactose-hydrolysis byproducts. PMID:24466218

  8. Archived News and Events

    Science.gov Websites

    DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home  | DU Uses | DUF6 Management | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet

  9. Effect of Oxide Coating on Performance of Copper-Zinc Oxide-Based Catalyst for Methanol Synthesis via Hydrogenation of Carbon Dioxide.

    PubMed

    Umegaki, Tetsuo; Kojima, Yoshiyuki; Omata, Kohji

    2015-11-16

    The effect of oxide coating on the activity of a copper-zinc oxide-based catalyst for methanol synthesis via the hydrogenation of carbon dioxide was investigated. A commercial catalyst was coated with various oxides by a sol-gel method. The influence of the types of promoters used in the sol-gel reaction was investigated. Temperature-programmed reduction-thermogravimetric analysis revealed that the reduction peak assigned to the copper species in the oxide-coated catalysts prepared using ammonia shifts to lower temperatures than that of the pristine catalyst; in contrast, the reduction peak shifts to higher temperatures for the catalysts prepared using L(+)-arginine. These observations indicated that the copper species were weakly bonded with the oxide and were easily reduced by using ammonia. The catalysts prepared using ammonia show higher CO₂ conversion than the catalysts prepared using L(+)-arginine. Among the catalysts prepared using ammonia, the silica-coated catalyst displayed a high activity at high temperatures, while the zirconia-coated catalyst and titania-coated catalyst had high activity at low temperatures. At high temperature the conversion over the silica-coated catalyst does not significantly change with reaction temperature, while the conversion over the zirconia-coated catalyst and titania-coated catalyst decreases with reaction time. From the results of FTIR, the durability depends on hydrophilicity of the oxides.

  10. Novel Solar Energy Conversion Materials by Design of Mn(II) Oxides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lany, S.; Peng, H.; Ndione, P.

    2013-01-01

    Solar energy conversion materials need to fulfill simultaneously a number of requirements in regard of their band-structure, optical properties, carrier transport, and doping. Despite their desirable chemical properties, e.g., for photo-electrocatalysis, transition-metal oxides usually do not have desirable semiconducting properties. Instead, oxides with open cation d-shells are typically Mott or charge-transfer insulators with notoriously poor transport properties, resulting from large effective electron/hole masses or from carrier self-trapping. Based on the notion that the electronic structure features (p-d interaction) supporting the p-type conductivity in d10 oxides like Cu2O and CuAlO2 occurs in a similar fashion also in the d5 (high-spin) oxides,more » we recently studied theoretically the band-structure and transport properties of the prototypical binary d5 oxides MnO and Fe2O3 [PRB 85, 201202(R)]. We found that MnO tends to self-trap holes by forming Mn+III, whereas Fe2O3 self-traps electrons by forming Fe+II. However, the self-trapping of holes is suppressed by when Mn is tetrahedrally coordinated, which suggests specific routes to design novel solar conversion materials by considering ternary Mn(II) oxides or oxide alloys. We are presenting theory, synthesis, and initial characterization for these novel energy materials.« less

  11. 76 FR 65544 - Standard Format and Content of License Applications for Mixed Oxide Fuel Fabrication Facilities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-21

    ...The U.S. Nuclear Regulatory Commission (NRC or Commission) is issuing a revision to regulatory guide (RG) 3.39, ``Standard Format and Content of License Applications for Mixed Oxide Fuel Fabrication Facilities.'' This guide endorses the standard format and content for license applications and integrated safety analysis (ISA) summaries described in the current version of NUREG-1718, ``Standard Review Plan for the Review of an Application for a Mixed Oxide (MOX) Fuel Fabrication Facility,'' as a method that the NRC staff finds acceptable for meeting the regulatory requirements of Title 10 of the Code of Federal Regulations (10 CFR) part 70, ``Domestic Licensing of Special Nuclear Material'' for mixed oxide fuel fabrication facilities.

  12. Fabrication of Yolk-Shell Cu@C Nanocomposites as High-Performance Catalysts in Oxidative Carbonylation of Methanol to Dimethyl Carbonate

    NASA Astrophysics Data System (ADS)

    Wang, Juan; Hao, Panpan; Shi, Ruina; Yang, Leilei; Liu, Shusen; Zhao, Jinxian; Ren, Jun; Li, Zhong

    2017-08-01

    A facile way was developed to fabricate yolk-shell composites with tunable Cu cores encapsulated within hollow carbon spheres (Cu@C) with an average diameter about 210 nm and cavity size about 80 nm. During pyrolysis, the confined nanospace of hollow cavity ensures that the nucleation-and-growth process of Cu nanocrystals take place exclusively inside the cavities. The size of Cu cores can be easily tuned from 30 to 55 nm by varying the copper salt concentration. By deliberately creating shell porosity through KOH chemical activation, at an optimized KOH/HCS mass ratio of 1/4, the catalytic performance for the oxidative carbonylation of methanol to dimethyl carbonate (DMC) of the activated sample is enhanced remarkably with TOF up to 8.6 h-1 at methanol conversion of 17.1%. The activated yolk-shell catalyst shows promising catalytic properties involving the reusability with slight loss of catalytic activity and negligible leaching of activated components even after seven recycles, which is beneficial to the implementation of clean production for the eco-friendly chemical DMC thoroughly.

  13. Synthesis of the antileukemic compound N,N(11)-[5-[bis(2-chloroethyl)amino]-1, 3-phenylene]bisurea.

    PubMed

    Denny, G H; Ryder, M A; DeMarco, A M; Babson, R D

    1976-03-01

    Conversion of 5-nitro-1, 3-benzenedicarboxylic acid (1) to the diamide 2 followed by hypochlorite rearrangement to the idamine 3 and subsequent reaction with acetic anhydride gave the bisacetamide 4. Reduction to the amine 5 followed by treatment with ethylene oxide formed the diol 6. The latter was converted to the bistosylate 7, which undrewent facile displacement with lithium chloride in acetone to give the mustard 8. Removal of the acetyl groups with hydrochloric acid gave 9, which reacted with potassium cyanate to provide the bisurea 10. In an alternative, but less satisfactory synthesis of 10, the compound (5-nitro-1, 3-phenylene) biscarbamic acid diphenyl ester (11), or the corresponding diethyl ester 12, was converted by ammonolysis to 13. The nitrodiurea 13 was next reduced to the amine 14, the hydrochloride of which reacted with ethylene oxide to give the diol 15. Treatment of the latter in dimethylformamide with N-chlorosuccinimide in the presence of triphenylphosphine gave 10 in low yield. The nitrogen mustards 8, 9 and 10 showed significant antitumor activities against P388 lymphocytic leukemia in mice.

  14. Pd loaded amphiphilic COF as catalyst for multi-fold Heck reactions, C-C couplings and CO oxidation

    PubMed Central

    Mullangi, Dinesh; Nandi, Shyamapada; Shalini, Sorout; Sreedhala, Sheshadri; Vinod, Chathakudath P.; Vaidhyanathan, Ramanathan

    2015-01-01

    COFs represent a class of polymers with designable crystalline structures capable of interacting with active metal nanoparticles to form excellent heterogeneous catalysts. Many valuable ligands/monomers employed in making coordination/organic polymers are prepared via Heck and C-C couplings. Here, we report an amphiphilic triazine COF and the facile single-step loading of Pd0 nanoparticles into it. An 18–20% nano-Pd loading gives highly active composite working in open air at low concentrations (Conc. Pd(0) <0.05 mol%, average TON 1500) catalyzing simultaneous multiple site Heck couplings and C-C couplings using ‘non-boronic acid’ substrates, and exhibits good recyclability with no sign of catalyst leaching. As an oxidation catalyst, it shows 100% conversion of CO to CO2 at 150 °C with no loss of activity with time and between cycles. Both vapor sorptions and contact angle measurements confirm the amphiphilic character of the COF. DFT-TB studies showed the presence of Pd-triazine and Pd-Schiff bond interactions as being favorable. PMID:26057044

  15. Development of a pMOSFET sensor with a Gd converter for low energy neutron dosimetry.

    PubMed

    Lee, N H; Kim, S H; Youk, G U; Park, I J; Kim, Y M

    2004-01-01

    A pMOSFET having a 10 microm thick Gadolinium (Gd) layer has been invented as a slow neutron sensor. When slow neutrons are incident to the Gd layer, conversion electrons, which generate electron-hole pairs in the SiO2 layer of the pMOSFET, are generated by a neutron capture process. The holes are easily trapped in the oxide and act as positive-charge centres in the oxide. Due to the induced charges, the threshold turn-on voltage of the pMOSFET is changed. The developed sensors were tested at a neutron beam port of the HANARO research reactor and a 60Co irradiation facility to investigate slow neutron response and gamma ray contamination, respectively. The resultant voltage change was proportional to the accumulated neutron dose and it was very sensitive to slow neutrons. Moreover, ionising radiation contamination was negligible. It can also be used in a mixed radiation field by subtracting the voltage change of a pMOSFET without Gd from that of the Gd-pMOSFET.

  16. Morphology-controlled cactus-like branched anatase TiO2 arrays with high light-harvesting efficiency for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wu, Wu-Qiang; Rao, Hua-Shang; Feng, Hao-Lin; Guo, Xin-Dong; Su, Cheng-Yong; Kuang, Dai-Bin

    2014-08-01

    The present work establishes a facile process for one-step hydrothermal growth of vertically aligned anatase cactus-like branched TiO2 (CBT) arrays on a transparent conducting oxide (TCO) substrate. Various CBT morphologies are obtained by adjusting the potassium titanium oxide oxalate (PTO) reactant concentration (from 0.05 M to 0.15 M) and this yields a morphologically-controllable branched TiO2 arrays geometry. The CBT arrays consist of a vertically oriented nanowire (NW) or nanosheet (NS) stem and a host of short nanorod (NR) branches. The hierarchical CBT arrays demonstrate their excellent candidatures as photoanodes, which are capable of exhibiting high light-harvesting efficiency in dye-sensitized solar cells (DSSCs). Consequently, DSSCs based on 7 μm long optimized CBT arrays (0.05 M PTO), which are assembled with high density and high aspect-ratio NR branches, exhibit an impressive power conversion efficiency of 6.43% under AM 1.5G one sun illumination. The high performance can be attributed to the prominent light-harvesting efficiency, resulting from larger surface area and superior light-scattering capability.

  17. An investigation on the photoelectrochemical properties of dye-sensitized solar cells based on graphene-TiO2 composite photoanodes

    NASA Astrophysics Data System (ADS)

    Zhu, Menghua; Li, Xin; Liu, Weiwei; Cui, Ying

    2014-09-01

    The graphene-TiO2 nanocomposite has been prepared by mixing graphene oxide (GO) and tetra-n-butyl titanate (TBT) followed by the facile hydrothermal process when the reduction of GO to reduced graphene oxide (RGO) and the hydrolysis of TBT to TiO2 happen. Characterization of the graphene-TiO2 nanostructures is investigated in detail by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. A dye-sensitized solar cell (DSSC) based on graphene-TiO2 composite photoelectrode exhibits a high energy conversion efficiency of 4.28%, compared with a DSSC based on pure TiO2 photoelectrode (3.11%), accompanied by an increment in both short-circuit photocurrent density and open-circuit voltage. The significant enhancement in performance of DSSC is investigated through intensity-modulated photovoltage spectroscopy, intensity-modulated photocurrent spectroscopy, and electrochemical impedance spectroscopy. It is found that the incorporation of two-dimensional graphene nanosheets in the TiO2 electrodes is the key factor leading to the improved photogenerated electron transfer ability and reduced charge recombination.

  18. Nitrogen–doped graphitized carbon shell encapsulated NiFe nanoparticles: A highly durable oxygen evolution catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du, Lei; Luo, Langli; Feng, Zhenxing

    Oxygen evolution reaction (OER) plays a crucial role in various energy conversion devices such as water electrolyzers and metal–air batteries. Precious metal catalysts such as Ir, Ru and their oxides are usually used for enhancing reaction kinetics but are limited by their scarce resource. The challenges associated with alternative non–precious metal catalysts such as transition metal oxides and (oxy)hydroxides etc. are their low electronic conductivity and durability. Herein, we report a highly active (360 mV overpotential at 10 mA cm–2GEO) and durable (no degradation after 20000 cycles) OER catalyst derived from bimetallic metal–organic frameworks (MOFs) precursors. This catalyst consists ofmore » NiFe nanoparticles encapsulated by nitrogen–doped graphitized carbon shells. The electron-donation/deviation from Fe and tuned electronic structure of metal cores by Ni are revealed to be primary contributors to the enhanced OER activity, whereas N concentration contributes negligibly. We further demonstrated that the structure and morphology of encapsulating carbon shells, which are the key factors influencing the durability, are facilely controlled by the chemical state of precursors.« less

  19. Metal oxide composite enabled nanotextured Si photoanode for efficient solar driven water oxidation.

    PubMed

    Sun, Ke; Pang, Xiaolu; Shen, Shaohua; Qian, Xueqiang; Cheung, Justin S; Wang, Deli

    2013-05-08

    We present a study of a transition metal oxide composite modified n-Si photoanode for efficient and stable water oxidation. This sputter-coated composite functions as a protective coating to prevent Si from photodecomposition, a Schottky heterojunction, a hole conducting layer for efficient charge separation and transportation, and an electrocatalyst to reduce the reaction overpotential. The formation of mixed-valence oxides composed of Ni and Ru effectively modifies the optical, electrical, and catalytic properties of the coating material, as well as the interfaces with Si. The successful application of this oxide composite on nanotextured Si demonstrates improved conversion efficiency due to enhanced catalytic activity, minimized reflection, and increased surface reaction sites. Although the coated nanotextured Si shows a noticeable degradation from 500 cycles of operation, the oxide composite provides a simple method to enable unstable photoanode materials for solar fuel conversion.

  20. DUF6 Draft EIS Public Hearing Transcripts

    Science.gov Websites

    and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » Conversion Facility EISs | Documents News | FAQs | Internet Resources | Glossary Help | Mailing Services | Contact Us

  1. DUF6 Conversion Facility EISs

    Science.gov Websites

    DUF6 Guide DU Uses DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources EISs | Documents News | FAQs | Internet Resources | Glossary Help | Mailing Services | Contact Us

  2. Recent Advances in Modeling Transition Metal Oxides for Photo-electrochemistry

    NASA Astrophysics Data System (ADS)

    Caspary Toroker, Maytal

    Computational research offers a wide range of opportunities for materials science and engineering, especially in the energy arena where there is a need for understanding how material composition and structure control energy conversion, and for designing materials that could improve conversion efficiency. Potential inexpensive materials for energy conversion devices are metal oxides. However, their conversion efficiency is limited by at least one of several factors: a too large band gap for efficiently absorbing solar energy, similar conduction and valence band edge characters that may lead to unfavorably high electron-hole recombination rates, a valence band edge that is not positioned well for oxidizing water, low stability, low electronic conductivity, and low surface reactivity. I will show how we model metal oxides with ab-initio methods, primarily DFT +U. Our previous results show that doping with lithium, sodium, or hydrogen could improve iron (II) oxide's electronic properties, and alloying with zinc or nickel could improve iron (II) oxide's optical properties. Furthermore, doping nickel (II) oxide with lithium could improve several key properties including solar energy absorption. In this talk I will highlight new results on our understanding of the mechanism of iron (III) oxide's surface reactivity. Our theoretical insights bring us a step closer towards understanding how to design better materials for photo-electrochemistry. References: 1. O. Neufeld and M. Caspary Toroker, ``Pt-doped Fe2O3 for enhanced water splitting efficiency: a DFT +U study'', J. Phys. Chem. C 119, 5836 (2015). 2. M. Caspary Toroker, ``Theoretical Insights into the Mechanism of Water Oxidation on Non-stoichiometric and Ti - doped Fe2O3 (0001)'', J. Phys. Chem. C, 118, 23162 (2014). This research was supported by the Morantz Energy Research Fund, the Nancy and Stephen Grand Technion Energy Program, the I-CORE Program of the Planning and Budgeting Committee, and The Israel Science Foundation (Grant No. 152/11).

  3. Iron(II) porphyrins induced conversion of nitrite into nitric oxide: A computational study.

    PubMed

    Zhang, Ting Ting; Liu, Yong Dong; Zhong, Ru Gang

    2015-09-01

    Nitrite reduction to nitric oxide by heme proteins was reported as a protective mechanism to hypoxic injury in mammalian physiology. In this study, the pathways of nitrite reduction to nitric oxide mediated by iron(II) porphyrin (P) complexes, which were generally recognized as models for heme proteins, were investigated by using density functional theory (DFT). In view of two type isomers of combination of nitrite and Fe(II)(P), N-nitro- and O-nitrito-Fe(II)-porphyrin complexes, and two binding sites of proton to the different O atoms of nitrite moiety, four main pathways for the conversion of nitrite into nitric oxide mediated by iron(II) porphyrins were proposed. The results indicate that the pathway of N-bound Fe(II)(P)(NO2) isomer into Fe(III)(P)(NO) and water is similar to that of O-bound isomer into nitric oxide and Fe(III)(P)(OH) in both thermodynamical and dynamical aspects. Based on the initial computational studies of five-coordinate nitrite complexes, the conversion of nitrite into NO mediated by Fe(II)(P)(L) complexes with 14 kinds of proximal ligands was also investigated. Generally, the same conclusion that the pathways of N-bound isomers are similar to those of O-bound isomer was obtained for iron(II) porphyrin with ligands. Different effects of ligands on the reduction reactions were also found. It is notable that the negative proximal ligands can improve reactive abilities of N-nitro-iron(II) porphyrins in the conversion of nitrite into nitric oxide compared to neutral ligands. The findings will be helpful to expand our understanding of the mechanism of nitrite reduction to nitric oxide by iron(II) porphyrins. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Graphene transforms wide band gap ZnS to a visible light photocatalyst. The new role of graphene as a macromolecular photosensitizer.

    PubMed

    Zhang, Yanhui; Zhang, Nan; Tang, Zi-Rong; Xu, Yi-Jun

    2012-11-27

    We report the assembly of nanosized ZnS particles on the 2D platform of a graphene oxide (GO) sheet by a facile two-step wet chemistry process, during which the reduced graphene oxide (RGO, also called GR) and the intimate interfacial contact between ZnS nanoparticles and the GR sheet are achieved simultaneously. The ZnS-GR nanocomposites exhibit visible light photoactivity toward aerobic selective oxidation of alcohols and epoxidation of alkenes under ambient conditions. In terms of structure-photoactivity correlation analysis, we for the first time propose a new photocatalytic mechanism where the role of GR in the ZnS-GR nanocomposites acts as an organic dye-like macromolecular "photosensitizer" for ZnS instead of an electron reservoir. This novel photocatalytic mechanism is distinctly different from all previous research on GR-semiconductor photocatalysts, for which GR is claimed to behave as an electron reservoir to capture/shuttle the electrons photogenerated from the semiconductor. This new concept of the reaction mechanism in graphene-semiconductor photocatalysts could provide a new train of thought on designing GR-based composite photocatalysts for targeting applications in solar energy conversion, promoting our in-depth thinking on the microscopic charge carrier transfer pathway connected to the interface between the GR and the semiconductor.

  5. Nitrogen–doped graphitized carbon shell encapsulated NiFe nanoparticles: A highly durable oxygen evolution catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Du, Lei; Luo, Langli; Feng, Zhenxing

    Oxygen evolution reaction (OER) plays a crucial role in various energy conversion devices such as water electrolyzers and metal–air batteries. Precious metal catalysts such as Ir, Ru and their oxides are usually used for enhanced reaction kinetics but are limited by their scarce resource. The challenges associated with alternative non–precious metal catalysts such as transition metal oxides and (oxy)hydroxides etc. are their low electronic conductivity and poor durability. Here, we report OER catalysts of NiFe nanoparticles encapsulated by nitrogen–doped graphitized carbon shells derived from bimetallic metal–organic frameworks (MOFs) precursors. The optimal OER catalyst shows excellent activity (360 mV overpotential atmore » 10 mA cm–2GEO) and durability (no obvious degradation after 20 000 cycles). The electron-donation from Fe and tuned electronic structure of metal cores by Ni are revealed to be primary contributors to the enhanced OER activity. We further demonstrated that the structure and morphology of encapsulating carbon shells, which are the key factors influencing the durability, are facilely controlled by chemical state of precursors. Severe metal particle growth probably caused by oxidation of carbon shells and encapsulated nanoparticles is believed to the main mechanism for activity degradation in these catalysts.« less

  6. Iron-antimony-based hybrid oxides as high-performance anodes for lithium-ion storage

    NASA Astrophysics Data System (ADS)

    Nguyen, Tuan Loi; Kim, Doo Soo; Hur, Jaehyun; Park, Min Sang; Yoon, Sukeun; Kim, Il Tae

    2018-06-01

    We report a facile approach to synthesize Fe-Sb-based hybrid oxides nanocomposites consisting of Sb, Sb2O3, and Fe3O4 for use as new anode materials for lithium-ion batteries. The composites are synthesized via galvanic replacement between Fe3+ and Sb at high temperature in triethylene glycol medium. The phase, morphology, and composition changes of the composites involved in the various stages of the replacement reaction are characterized using X-ray diffractometry, high-resolution transmission electron microscopy, and energy dispersive X-ray spectroscopy. The as-prepared composites have different compositions with very small particle sizes (<< 10 nm). The FexSbyOz-18 h composite, for instance, exhibits high capacity, better cyclic stability, and rate performance than other composites, with a highly stable specific capacity of 434 mAh g-1 at 500 cycles. The excellent electrochemical performance can be ascribed to the high interfacial contact area between the nanocomposite and electrolyte, stable structure of the composites owing to a mixture of inactive phases generated by the conversion reaction between Li+ and oxide metal-whose structure serves as an electron conductor, inhibits agglomeration of Sb particles, and acts as an effective buffer against volume change of Sb during cycling-and high Li+ diffusion ability.

  7. Catalytic wet air oxidation of aniline with nanocasted Mn-Ce-oxide catalyst.

    PubMed

    Levi, R; Milman, M; Landau, M V; Brenner, A; Herskowitz, M

    2008-07-15

    The catalytic wet air oxidation of aqueous solution containing 1000 ppm aniline was conducted in a trickle-bed reactor packed with a novel nanocasted Mn-Ce-oxide catalyst (surface area of 300 m2/g) prepared using SBA-15 silica as a hard template. A range of liquid hourly space velocities (5-20 h(-1)) and temperatures (110-140 degrees C) at 10 bar of oxygen were tested. The experiments were conducted to provide the intrinsic performance of the catalysts. Complete aniline conversion, 90% TOC conversion, and 80% nitrogen mineralization were achieved at 140 degrees C and 5 h(-1). Blank experiments yielded relatively low homogeneous aniline (<35%) and negligible TOC conversions. Fast deactivation of the catalysts was experienced due to leaching caused by complexation with aniline. Acidification of the solution with HCI (molar HCI to aniline ratio of 1.2) was necessary to avoid colloidization and leaching of the nanoparticulate catalyst components. The catalyst displayed stable performance for over 200 h on stream.

  8. A review of high temperature co-electrolysis of H2O and CO2 to produce sustainable fuels using solid oxide electrolysis cells (SOECs): advanced materials and technology.

    PubMed

    Zheng, Yun; Wang, Jianchen; Yu, Bo; Zhang, Wenqiang; Chen, Jing; Qiao, Jinli; Zhang, Jiujun

    2017-03-06

    High-temperature solid oxide electrolysis cells (SOECs) are advanced electrochemical energy storage and conversion devices with high conversion/energy efficiencies. They offer attractive high-temperature co-electrolysis routes that reduce extra CO 2 emissions, enable large-scale energy storage/conversion and facilitate the integration of renewable energies into the electric grid. Exciting new research has focused on CO 2 electrochemical activation/conversion through a co-electrolysis process based on the assumption that difficult C[double bond, length as m-dash]O double bonds can be activated effectively through this electrochemical method. Based on existing investigations, this paper puts forth a comprehensive overview of recent and past developments in co-electrolysis with SOECs for CO 2 conversion and utilization. Here, we discuss in detail the approaches of CO 2 conversion, the developmental history, the basic principles, the economic feasibility of CO 2 /H 2 O co-electrolysis, and the diverse range of fuel electrodes as well as oxygen electrode materials. SOEC performance measurements, characterization and simulations are classified and presented in this paper. SOEC cell and stack designs, fabrications and scale-ups are also summarized and described. In particular, insights into CO 2 electrochemical conversions, solid oxide cell material behaviors and degradation mechanisms are highlighted to obtain a better understanding of the high temperature electrolysis process in SOECs. Proposed research directions are also outlined to provide guidelines for future research.

  9. Selective oxidation of benzyl alcohols to benzoic acid catalyzed by eco-friendly cobalt thioporphyrazine catalyst supported on silica-coated magnetic nanospheres.

    PubMed

    Li, Huan; Cao, Lan; Yang, Changjun; Zhang, Zhehui; Zhang, Bingguang; Deng, Kejian

    2017-10-01

    A novel magnetically recoverable thioporphyrazine catalyst (CoPz(S-Bu) 8 /SiO 2 @Fe 3 O 4 ) was prepared by immobilization of the cobalt octkis(butylthio) porphyrazine complex (CoPz(S-Bu) 8 ) on silica-coated magnetic nanospheres (SiO 2 @Fe 3 O 4 ). The composite CoPz(S-Bu) 8 /SiO 2 @Fe 3 O 4 appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide (H 2 O 2 ) as oxidant under Xe-lamp irradiation, with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number (TON) of 61.7 at ambient temperature. The biomimetic catalyst CoPz(S-Bu) 8 was supported on the magnetic carrier SiO 2 @Fe 3 O 4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz(S-Bu) 8 can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications. Copyright © 2017. Published by Elsevier B.V.

  10. Korean Waste Management Law and Waste Disposal Forms.

    DTIC Science & Technology

    1991-03-01

    disinfection facility, dewatering facility, and other auxiliary facilities 2) An aerobic treatment facility composed of intake, detention basin, aerobic ... digestion or oxidation treatment facility, biological treatment facility, disinfection facility, dewatering facility, and other auxiliary facilities

  11. 40 CFR 63.8698 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... facility used to transfer oxidized asphalt from a storage tank into a tank truck, rail car, or barge... facility includes one or more asphalt flux blowing stills, asphalt flux storage tanks storing asphalt flux intended for processing in the blowing stills, oxidized asphalt storage tanks, and oxidized asphalt loading...

  12. Investigation of buried homojunctions in p-InP formed during sputter deposition of both indium tin oxide and indium oxide

    NASA Technical Reports Server (NTRS)

    Gessert, T. A.; Li, X.; Wanlass, M. W.; Nelson, A. J.; Coutts, T. J.

    1990-01-01

    While dc magnetron sputter deposition of indium tin oxide leads to the formation of a buried homojunction in single crystal p-type InP, the mechanism of type conversion of the InP surface is not apparent. In view of the recent achievement of nearly 17-percent global efficiencies for cells fabricated solely by sputter deposition of In2O3, it is presently surmised that tin may not be an essential element in type conversion. A variety of electrical and optical techniques are presently used to evaluate the changes at both indium tin oxide/InP and indium oxide/InP interfaces. Such mechanisms as the passivation of acceptors by hydrogen, and sputter damage, are found to occur simultaneously.

  13. SCR atmosphere induced reduction of oxidized mercury over CuO-CeO2/TiO2 catalyst.

    PubMed

    Li, Hailong; Wu, Shaokang; Wu, Chang-Yu; Wang, Jun; Li, Liqing; Shih, Kaimin

    2015-06-16

    CuO-CeO2/TiO2 (CuCeTi) catalyst synthesized by a sol-gel method was employed to investigate mercury conversion under a selective catalytic reduction (SCR) atmosphere (NO, NH3 plus O2). Neither NO nor NH3 individually exhibited an inhibitive effect on elemental mercury (Hg(0)) conversion in the presence of O2. However, Hg(0) conversion over the CuCeTi catalyst was greatly inhibited under SCR atmosphere. Systematic experiments were designed to investigate the inconsistency and explore the in-depth mechanisms. The results show that the copresence of NO and NH3 induced reduction of oxidized mercury (Hg(2+), HgO in this study), which offset the effect of catalytic Hg(0) oxidation, and hence resulted in deactivation of Hg(0) conversion. High NO and NH3 concentrations with a NO/NH3 ratio of 1.0 facilitated Hg(2+) reduction and therefore lowered Hg(0) conversion. Hg(2+) reduction over the CuCeTi catalyst was proposed to follow two possible mechanisms: (1) direct reaction, in which NO and NH3 react directly with HgO to form N2 and Hg(0); (2) indirect reaction, in which the SCR reaction consumed active surface oxygen on the CuCeTi catalyst, and reduced species on the CuCeTi catalyst surface such as Cu2O and Ce2O3 robbed oxygen from adjacent HgO. Different from the conventionally considered mechanisms, that is, competitive adsorption responsible for deactivation of Hg(0) conversion, this study reveals that oxidized mercury can transform into Hg(0) under SCR atmosphere. Such knowledge is of fundamental importance in developing efficient and economical mercury control technologies for coal-fired power plants.

  14. Materials Science Clean Room Facility at Tulane University (Final Technical Report)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Altiero, Nicholas

    2010-09-30

    The project involves conversion of a 3,000 sq. ft. area into a clean room facility for materials science research. It will be accomplished in phases. Phase I will involve preparation of the existing space, acquisition and installation of clean room equipped with a pulsed laser deposition (PLD) processing system, and conversion of ancillary space to facilitate the interface with the clean room. From a capital perspective, Phases II and III will involve the acquisition of additional processing, fabrication, and characterization equipment and capabilities.

  15. Direct conversion of alcohols to α-chloro aldehydes and α-chloro ketones.

    PubMed

    Jing, Yuanyuan; Daniliuc, Constantin G; Studer, Armido

    2014-09-19

    Direct conversion of primary and secondary alcohols into the corresponding α-chloro aldehydes and α-chloro ketones using trichloroisocyanuric acid, serving both as stoichiometric oxidant and α-halogenating reagent, is reported. For primary alcohols, TEMPO has to be added as an oxidation catalyst, and for the transformation of secondary alcohols (TEMPO-free protocol), MeOH as an additive is essential to promote chlorination of the intermediary ketones.

  16. Photo Degradation of Methyl Orange by Persulfate Activated with Zero Valent Iron

    NASA Astrophysics Data System (ADS)

    Munkoeva, V. A.; Sizykh, M. R.; Batoeva, A. A.

    2017-11-01

    The oxidative degradation of Methyl Orange (MO) subjected to direct photolysis (Solar) and various oxidative systems was studied. The comparative experiments have shown that MO conversion and mineralization increases in the following order: Solar ∼ Solar/Fe0 ∼ Solar/S2O82- < S2O82-/Fe0 < Solar/S2O82-/Fe0. The influence of the main factors (duration of exposure, the ratio of initial concentrations of MO:S2O82-:Fe0, pH and temperature of the reaction medium) on the degree of MO conversion and mineralization was studied. The optimal pH and temperature of the reaction medium were 5.8 and 25°C, respectively. The rate of MO decomposition and mineralization increased proportionally to the initial concentration of the oxidant at the molar ratios [S2O82-] :[MO] ≤ 12. Judging by the nature of the kinetic curves, a further increase of this ratio is impractical. However, an increase in the oxidant concentration had a positive effect on the degrees of conversion and mineralization of total organic carbon (TOC). Thus, at the ratios of 12:1 and 48:1, the conversion efficiency of TOC was 23 and 60 %, respectively. The optimal concentration of Fe0 was 100 mg/l.

  17. Research on solvent-refined coal. Quarterly technical progress report, April 1, 1981-June 30, 1981

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1981-10-01

    This report describes progress on the Research on Solvent Refined Coal project by The Pittsburg and Midway Coal Mining Co.'s Merriam Laboratory during the second quarter of 1981. Alexander Mine coal was evaluated as a feedstock for major liquefaction facilities and had a yield structure similar to other reactive Pittsburgh seam coals at standard SRC II conditions. Two lots of coal from the Ireland Mine (Pittsburgh seam) were found to be of nearly the same composition and produced essentially the same yields. Two experiments in which coal-derived nonvolatile organic matter was processed without fresh coal feed indicate constant rates ofmore » conversion of SRC to oil and gas. Insoluble organic matter (IOM) remained unconverted. The naphtha and middle distillate products from the deep conversion contained less sulfur but more nitrogen than those from conventional SRC II processing. Encouraging results were obtained when a very small amount of iron oxide dispersed on alumina was added to Kaiparowits coal which cannot be processed at normal SRC II conditions without added catalyst. Subbituminous coals from the McKinley and Edna Mines were processed successfully with added pyrite but would not run when the added catalyst was removed.« less

  18. Remediation of aged diesel contaminated soil by alkaline activated persulfate.

    PubMed

    Lominchar, M A; Santos, A; de Miguel, E; Romero, A

    2018-05-01

    The present work studies the efficiency of alkaline activated persulfate (PS) to remediate an aged diesel fuel contaminated soil from a train maintenance facility. The Total Petroleum Hydrocarbon (TPH) concentration in soil was approximately 5000mgkg -1 with a ratio of aliphatic:aromatic compounds of 70:30. Aromatic compounds were mainly naphtalenes and phenanthrenes. The experiments were performed in batch mode where different initial concentrations of persulfate (105mM, 210mM and 420mM) and activator:persulfate ratios (2 and 4) were evaluated, with NaOH used as activator. Runs were carried out during 56days. Complete TPH conversion was obtained with the highest concentration of PS and activator, whereas in the other runs the elimination of fuel ranged between 60 and 77%. Besides, the abatement of napthalenes and phenantrenes was faster than aliphatic reduction (i. e. after 4days of treatment, the conversions of the aromatic compounds were around 0.8 meanwhile the aliphatic abatements were 0.55) and no aromatic oxidation intermediates from naphtalenes or phenantrenes were detected. These results show that this technology is effective for the remediation of aged diesel in soil with alkaline pH. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Effect of Oxide Coating on Performance of Copper-Zinc Oxide-Based Catalyst for Methanol Synthesis via Hydrogenation of Carbon Dioxide

    PubMed Central

    Umegaki, Tetsuo; Kojima, Yoshiyuki; Omata, Kohji

    2015-01-01

    The effect of oxide coating on the activity of a copper-zinc oxide–based catalyst for methanol synthesis via the hydrogenation of carbon dioxide was investigated. A commercial catalyst was coated with various oxides by a sol-gel method. The influence of the types of promoters used in the sol-gel reaction was investigated. Temperature-programmed reduction-thermogravimetric analysis revealed that the reduction peak assigned to the copper species in the oxide-coated catalysts prepared using ammonia shifts to lower temperatures than that of the pristine catalyst; in contrast, the reduction peak shifts to higher temperatures for the catalysts prepared using L(+)-arginine. These observations indicated that the copper species were weakly bonded with the oxide and were easily reduced by using ammonia. The catalysts prepared using ammonia show higher CO2 conversion than the catalysts prepared using L(+)-arginine. Among the catalysts prepared using ammonia, the silica-coated catalyst displayed a high activity at high temperatures, while the zirconia-coated catalyst and titania-coated catalyst had high activity at low temperatures. At high temperature the conversion over the silica-coated catalyst does not significantly change with reaction temperature, while the conversion over the zirconia-coated catalyst and titania-coated catalyst decreases with reaction time. From the results of FTIR, the durability depends on hydrophilicity of the oxides. PMID:28793674

  20. Catalytic oxidation of light alkanes in presence of a base

    DOEpatents

    Bhinde, Manoj V.; Bierl, Thomas W.

    1998-01-01

    The presence of a base in the reaction mixture in a metal-ligand catalyzed partial oxidation of alkanes results in sustained catalyst activity, and in greater percent conversion as compared with oxidation in the absence of base, while maintaining satisfactory selectivity for the desired oxidation, for example the oxidation of isobutane to isobutanol.

  1. An oxidation and erosion test facility for cooled panels

    NASA Technical Reports Server (NTRS)

    Swartwout, W. H.; Erdos, J. I.; Engers, R. J.; Prescott, C.

    1992-01-01

    The Panel Oxidation and Erosion Testbed (POET) facility under construction at GASL to provide the required test environment is described. The POET facility comprises three major element including a vitiated air heater, a supersonic nozzle, and a test section. A hydrogen-fueld vitiated air heater will provide the oxidizing and erosive environment. The flow through the test section characterized by low supersonic speed and Mach number of 1.4 will maximize the local heat transfer rate and the local surface shear stress.

  2. Conversion of visible light to electrical energy - Stable cadmium selenide photoelectrodes in aqueous electrolytes

    NASA Technical Reports Server (NTRS)

    Wrighton, M. S.; Ellis, A. B.; Kaiser, S. W.

    1977-01-01

    Stabilization of n-type CdSe to photoanodic dissolution is reported. The stabilization is accomplished by the competitive oxidation of S(--) or S(n)(--) at the CdSe photoanode in an electrochemical cell. Such stabilized cells are shown to sustain the conversion of low energy (not less than 1.7 eV) visible light to electricity with good efficiency and no deterioration of the CdSe photoelectrode or of the electrolyte. The electrolyte undergoes no net chemical change because the oxidation occurring at the photoelectrode is reversed at the cathode. Conversion of monochromatic light at 633 nm to electricity is shown to be up to approximately 9% efficient with output potentials of approximately 0.4 V. Conversion of solar energy to electricity is estimated to be approximately 2% efficient.

  3. Effect of Native Oxide Film on Commercial Magnesium Alloys Substrates and Carbonate Conversion Coating Growth and Corrosion Resistance

    PubMed Central

    Feliu, Sebastián; Samaniego, Alejandro; Bermudez, Elkin Alejandro; El-Hadad, Amir Abdelsami; Llorente, Irene; Galván, Juan Carlos

    2014-01-01

    Possible relations between the native oxide film formed spontaneously on the AZ31 and AZ61 magnesium alloy substrates with different surface finish, the chemistry of the outer surface of the conversion coatings that grows after their subsequent immersion on saturated aqueous NaHCO3 solution treatment and the enhancement of corrosion resistance have been studied. The significant increase in the amount of aluminum and carbonate compounds on the surface of the conversion coating formed on the AZ61 substrate in polished condition seems to improve the corrosion resistance in low chloride ion concentration solutions. In contrast, the conversion coatings formed on the AZ31 substrates in polished condition has little effect on their protective properties compared to the respective as-received surface. PMID:28788582

  4. Effect of Native Oxide Film on Commercial Magnesium Alloys Substrates and Carbonate Conversion Coating Growth and Corrosion Resistance.

    PubMed

    Feliu, Sebastián; Samaniego, Alejandro; Bermudez, Elkin Alejandro; El-Hadad, Amir Abdelsami; Llorente, Irene; Galván, Juan Carlos

    2014-03-28

    Possible relations between the native oxide film formed spontaneously on the AZ31 and AZ61 magnesium alloy substrates with different surface finish, the chemistry of the outer surface of the conversion coatings that grows after their subsequent immersion on saturated aqueous NaHCO₃ solution treatment and the enhancement of corrosion resistance have been studied. The significant increase in the amount of aluminum and carbonate compounds on the surface of the conversion coating formed on the AZ61 substrate in polished condition seems to improve the corrosion resistance in low chloride ion concentration solutions. In contrast, the conversion coatings formed on the AZ31 substrates in polished condition has little effect on their protective properties compared to the respective as-received surface.

  5. Evidence of the direct involvement of the substrate TCP radical in functional switching from oxyferrous O2 carrier to ferric peroxidase in the dual-function hemoglobin/dehaloperoxidase from Amphitrite ornata.

    PubMed

    Sun, Shengfang; Sono, Masanori; Du, Jing; Dawson, John H

    2014-08-05

    The coelomic O2-binding hemoglobin dehaloperoxidase (DHP) from the sea worm Amphitrite ornata is a dual-function heme protein that also possesses a peroxidase activity. Two different starting oxidation states are required for reversible O2 binding (ferrous) and peroxidase (ferric) activity, bringing into question how DHP manages the two functions. In our previous study, the copresence of substrate 2,4,6-trichlorophenol (TCP) and H2O2 was found to be essential for the conversion of oxy-DHP to enzymatically active ferric DHP. On the basis of that study, a functional switching mechanism involving substrate radicals (TCP(•)) was proposed. To further support this mechanism, herein we report details of our investigations into the H2O2-mediated conversion of oxy-DHP to the ferric or ferryl ([TCP] < [H2O2]) state triggered by both biologically relevant [TCP and 4-bromophenol (4-BP)] and nonrelevant (ferrocyanide) compounds. At <50 μM H2O2, all of these conversion reactions are completely inhibited by ferric heme ligands (KCN and imidazole), indicating the involvement of ferric DHP. Furthermore, the spin-trapping reagent 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) effectively inhibits the TCP/4-BP (but not ferrocyanide)-triggered conversion of oxy-DHP to ferric DHP. These results and O2 concentration-dependent conversion rates observed in this study demonstrate that substrate TCP triggers the conversion of oxy-DHP to a peroxidase by TCP(•) oxidation of the deoxyferrous state. TCP(•) is progressively generated, by increasingly produced amounts of ferric DHP, upon H2O2 oxidation of TCP catalyzed initially by trace amounts of ferric enzyme present in the oxy-DHP sample. The data presented herein further address the mechanism of how the halophenolic substrate triggers the conversion of hemoglobin DHP into a peroxidase.

  6. Acid-catalyzed oxidation of 2,4-dichlorophenoxyacetic acid by ammonium nitrate in aqueous solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leavitt, D.D.; Abraham, M.A.

    1990-04-01

    2,4-Dichlorophenoxyacetic acid (2,4-D) was oxidized to CO{sub 2} and water by homogeneous, liquid-phase reaction with ammonium nitrate at temperatures between 250 and 450{degree}F and pressures below 100 psi. N{sub 2} and N{sub 2}O were produced from the thermal decomposition of the ammonium nitrate oxidant. An unexpected maximum in conversion was observed at an intermediate reaction temperature, which was consistent with rapid thermal decomposition of the NH{sub 4}NO{sub 3} oxidant. Postulated reaction pathways consisting of simultaneous oxidation of 2,4-D and decomposition of the oxidant allowed estimation of kinetic constants from best-fit analysis of the data. The proposed reaction model provided amore » mathematical description of 2,4-D conversion, which allowed extrapolation of the results to reaction conditions and reactor configurations that were not experimentally investigated.« less

  7. Characterization of Representative Materials in Support of Safe, Long Term Storage of Surplus Plutonium in DOE-STD-3013 Containers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Narlesky, Joshua E.; Stroud, Mary Ann; Smith, Paul Herrick

    2013-02-15

    The Surveillance and Monitoring Program is a joint Los Alamos National Laboratory/Savannah River Site effort funded by the Department of Energy-Environmental Management to provide the technical basis for the safe, long-term storage (up to 50 years) of over 6 metric tons of plutonium stored in over 5,000 DOE-STD-3013 containers at various facilities around the DOE complex. The majority of this material is plutonium that is surplus to the nuclear weapons program, and much of it is destined for conversion to mixed oxide fuel for use in US nuclear power plants. The form of the plutonium ranges from relatively pure metalmore » and oxide to very impure oxide. The performance of the 3013 containers has been shown to depend on moisture content and on the levels, types and chemical forms of the impurities. The oxide materials that present the greatest challenge to the storage container are those that contain chloride salts. Other common impurities include oxides and other compounds of calcium, magnesium, iron, and nickel. Over the past 15 years the program has collected a large body of experimental data on 54 samples of plutonium, with 53 chosen to represent the broader population of materials in storage. This paper summarizes the characterization data, moisture analysis, particle size, surface area, density, wattage, actinide composition, trace element impurity analysis, and shelf life surveillance data and includes origin and process history information. Limited characterization data on fourteen nonrepresentative samples is also presented.« less

  8. Characterization of representative materials in support of safe, long term storage of surplus plutonium in DOE-STD-3013 containers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Paul H; Narlesky, Joshua E; Worl, Laura A

    2010-01-01

    The Surveillance and Monitoring Program (SMP) is a joint LANL/SRS effort funded by DOE/EM to provide the technical basis for the safe, long-term storage (up to 50 years) of over 6 metric tons of plutonium stored in over 5000 DOE-STD-3013 containers at various facilities around the DOE complex. The majority of this material is plutonium that is surplus to the nuclear weapons program, and much of it is destined for conversion to mixed oxide fuel for use in US nuclear power plants. The form of the plutonium ranges from relatively pure metal and oxide to very impure oxide. The performancemore » of the 3013 containers has been shown to depend on moisture content and on the levels, types and chemical forms of the impurities. The oxide materials that present the greatest challenge to the storage container are those that contain chloride salts. The chlorides (NaCl, KCl, CaCl{sub 2}, and MgCl{sub 2}) range from less than half of the impurities present to nearly all the impurities. Other common impurities include oxides and other compounds of calcium, magnesium, iron, and nickel. Over the past 15 years the program has collected a large body of experimental data on over 60 samples of plutonium chosen to represent the broader population of materials in storage. This paper will summarize the characterization data, including the origin and process history, particle size, surface area, density, calorimetry, chemical analysis, moisture analysis, prompt gamma, gas generation and corrosion behavior.« less

  9. Reduced TiO2-Graphene Oxide Heterostructure As Broad Spectrum-Driven Efficient Water-Splitting Photocatalysts.

    PubMed

    Li, Lihua; Yu, Lili; Lin, Zhaoyong; Yang, Guowei

    2016-04-06

    The reduced TiO2-graphene oxide heterostructure as an alternative broad spectrum-driven efficient water splitting photocatalyst has become a really interesting topic, however, its syntheses has many flaws, e.g., tedious experimental steps, time-consuming, small scale production, and requirement of various additives, for example, hydrazine hydrate is widely used as reductant to the reduction of graphene oxide, which is high toxicity and easy to cause the second pollution. For these issues, herein, we reported the synthesis of the reduced TiO2-graphene oxide heterostructure by a facile chemical reduction agent-free one-step laser ablation in liquid (LAL) method, which achieves extended optical response range from ultraviolet to visible and composites TiO(2-x) (reduced TiO2) nanoparticle and graphene oxide for promoting charge conducting. 30.64% Ti(3+) content in the reduced TiO2 nanoparticles induces the electronic reconstruction of TiO2, which results in 0.87 eV decrease of the band gap for the visible light absorption. TiO(2-x)-graphene oxide heterostructure achieved drastically increased photocatalytic H2 production rate, up to 23 times with respect to the blank experiment. Furthermore, a maximum H2 production rate was measured to be 16 mmol/h/g using Pt as a cocatalyst under the simulated sunlight irradiation (AM 1.5G, 135 mW/cm(2)), the quantum efficiencies were measured to be 5.15% for wavelength λ = 365 ± 10 nm and 1.84% for λ = 405 ± 10 nm, and overall solar energy conversion efficiency was measured to be 14.3%. These findings provided new insights into the broad applicability of this methodology for accessing fascinate photocatalysts.

  10. Facile and sustainable synthesis of shaped iron oxide nanoparticles: effect of iron precursor salts on the shapes of iron oxides.

    PubMed

    Sayed, Farheen N; Polshettiwar, Vivek

    2015-05-05

    A facile and sustainable protocol for synthesis of six different shaped iron oxides is developed. Notably, all the six shapes of iron oxides can be synthesised using exactly same synthetic protocol, by simply changing the precursor iron salts. Several of the synthesised shapes are not reported before. This novel protocol is relatively easy to implement and could contribute to overcome the challenge of obtaining various shaped iron oxides in economical and sustainable manner.

  11. Facile and Sustainable Synthesis of Shaped Iron Oxide Nanoparticles: Effect of Iron Precursor Salts on the Shapes of Iron Oxides

    PubMed Central

    Sayed, Farheen N.; Polshettiwar, Vivek

    2015-01-01

    A facile and sustainable protocol for synthesis of six different shaped iron oxides is developed. Notably, all the six shapes of iron oxides can be synthesised using exactly same synthetic protocol, by simply changing the precursor iron salts. Several of the synthesised shapes are not reported before. This novel protocol is relatively easy to implement and could contribute to overcome the challenge of obtaining various shaped iron oxides in economical and sustainable manner. PMID:25939969

  12. Enhancement of Energy Conversion Efficiency for Dye Sensitized Solar Cell Using Zinc Oxide Photoanode

    NASA Astrophysics Data System (ADS)

    Jamalullail, N.; Smohamad, I.; Nnorizan, M.; Mahmed, N.

    2018-06-01

    Dye sensitized solar cell (DSSC) is a third generation solar cell that is well known for its low cost, simple fabrication process and promised reasonable energy conversion efficiency. Basic structure of DSSC is composed of photoanode, dye sensitizer, electrolyte that is sandwiched together in between two transparent conductive oxide (TCO) glasses. Each of the components in the DSSC contributes important role that affect the energy conversion efficiency. In this research, the commonly used titanium dioxide (TiO2) photoanode has previously reported to have high recombination rate and low electron mobility which caused efficiency loss had been compared with the zinc oxide (ZnO) photoanode with high electron mobility (155 cm2V-1s-1). Both of these photoanodes had been deposited through doctor blade technique. The electrical performance of the laboratory based DSSCs were tested using solar cell simulator and demonstrated that ZnO is a better photoanode compared to TiO2 with the energy conversion efficiency of 0.34% and 0.29% respectively. Nanorods shape morphology was observed in ZnO photoanode with average particle size of 41.60 nm and average crystallite size of 19.13 nm. This research proved that the energy conversion efficiency of conventional TiO2 based photoanode can be improved using ZnO material.

  13. Coal conversion products Industrial applications

    NASA Technical Reports Server (NTRS)

    Warren, D.; Dunkin, J.

    1980-01-01

    The synfuels economic evaluation model was utilized to analyze cost and product economics of the TVA coal conversion facilities. It is concluded that; (1) moderate yearly future escalations ( 6%) in current natural gas prices will result in medium-Btu gas becoming competitive with natural gas at the plant boundary; (2) utilizing DRI price projections, the alternate synfuel products, except for electricity, will be competitive with their counterparts; (3) central site fuel cell generation of electricity, utilizing MBG, is economically less attractive than the other synthetic fuels, given projected price rises in electricity produced by other means; and (4) because of estimated northern Alabama synfuels market demands, existing conventional fuels, infrastructure and industrial synfuels retrofit problems, a diversity of transportable synfuels products should be produced by the conversion facility.

  14. How Metric Conversion Affects Administrative Practices

    ERIC Educational Resources Information Center

    Straka, M. K.

    1977-01-01

    Changes necessary in the administrative activities of educational institutions following conversion to the metric system are outlined for secretarial practices, purchasing, internal reporting and forms, computer operations, travel, publications, buildings and plant, new buildings, sport facilities, and health services. (MF)

  15. Complex oxides useful for thermoelectric energy conversion

    DOEpatents

    Majumdar, Arunava [Orinda, CA; Ramesh, Ramamoorthy [Moraga, CA; Yu, Choongho [College Station, TX; Scullin, Matthew L [Berkeley, CA; Huijben, Mark [Enschede, NL

    2012-07-17

    The invention provides for a thermoelectric system comprising a substrate comprising a first complex oxide, wherein the substrate is optionally embedded with a second complex oxide. The thermoelectric system can be used for thermoelectric power generation or thermoelectric cooling.

  16. New Concepts for Compact Space Reactor Power Systems for Space Based Radar Applications: A Feasibility Study

    DTIC Science & Technology

    1989-12-01

    SPENT FUEL REPROCESSING COULD ALSO BE EMPLOYED IRRADIATION EXPERIENCE - EXTREMELY LIMITED - JOINT US/UK PROGRAM (ONGOING) - TUI/KFK PROGRAM (CANCELED...only the use of off-the-shelf technologies. For example, conventional fuel technology (uranium dioxide), conventional thermionic conversion...advanced fuel (Americium oxide, A1TI2O3) and advanced thermionic conversion. Concept C involves use of an advanced fuel (Americium oxide, Arri203

  17. Carbothermic Synthesis of 820 m UN Kernels: Literature Review, Thermodynamics, Analysis, and Related Experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lindemer, Terrence; Voit, Stewart L; Silva, Chinthaka M

    2014-01-01

    The U.S. Department of Energy is considering a new nuclear fuel that would be less susceptible to ruptures during a loss-of-coolant accident. The fuel would consist of tristructural isotropic coated particles with large, dense uranium nitride (UN) kernels. This effort explores many factors involved in using gel-derived uranium oxide-carbon microspheres to make large UN kernels. Analysis of recent studies with sufficient experimental details is provided. Extensive thermodynamic calculations are used to predict carbon monoxide and other pressures for several different reactions that may be involved in conversion of uranium oxides and carbides to UN. Experimentally, the method for making themore » gel-derived microspheres is described. These were used in a microbalance with an attached mass spectrometer to determine details of carbothermic conversion in argon, nitrogen, or vacuum. A quantitative model is derived from experiments for vacuum conversion to an uranium oxide-carbide kernel.« less

  18. Application of Fenton oxidation to cosmetic wastewaters treatment.

    PubMed

    Bautista, P; Mohedano, A F; Gilarranz, M A; Casas, J A; Rodriguez, J J

    2007-05-08

    The removal of organic matter (TOC and COD) from a cosmetic wastewater by Fenton oxidation treatment has been evaluated. The operating conditions (temperature as well as ferrous ion and hydrogen peroxide dosage) have been optimized. Working at an initial pH equal to 3.0, a Fe(2+) concentration of 200 mg/L and a H(2)O(2) concentration to COD initial weight ratio corresponding to the theoretical stoichiometric value (2.12), a TOC conversion higher than 45% at 25 degrees C and 60% at 50 degrees C was achieved. Application of the Fenton oxidation process allows to reach the COD regional limit for industrial wastewaters discharges to the municipal sewer system. A simple kinetic analysis based on TOC was carried out. A second-order equation describes well the overall kinetics of the process within a wide TOC conversion range covering up to the 80-90% of the maximum achievable conversion.

  19. Comparison of coal reactivityduring conversion into different oxidizing medium

    NASA Astrophysics Data System (ADS)

    Korotkikh, A. G.; Slyusarskiy, K. V.; Larionov, K. B.; Osipov, V. I.

    2016-10-01

    Acoal conversion process of different coal samples into three different types of oxidizing medium (argon, air and steam) were studied by means of thermogravimetry. Two coal types with different metamorphism degree (lignite and bituminous coal) were used. The experimental procedure was carried out in non-isothermal conditions in temperature range from 373 K to 1273 K with 20 K/min heating rate. Purge gas consisted of argon and oxidizer with volumetric ratio 1:24 and had 250 ml/min flow rate.The ignition and burnout indexes were calculated to evaluate sample reactivity at different oxidizing mediums. The highest reactivity coefficient values in same atmosphere were obtained for lignite. It was caused by higher particle special surface area and volatile matter content.

  20. Catalytic oxidation of light alkanes in presence of a base

    DOEpatents

    Bhinde, M.V.; Bierl, T.W.

    1998-03-03

    The presence of a base in the reaction mixture in a metal-ligand catalyzed partial oxidation of alkanes results in sustained catalyst activity, and in greater percent conversion as compared with oxidation in the absence of base, while maintaining satisfactory selectivity for the desired oxidation, for example the oxidation of isobutane to isobutanol. 1 fig.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sridharan, Kumar; Anderson, Mark

    The supercritical CO{sub 2} Brayton cycle is gaining importance for power conversion in the Generation IV fast reactor system because of its high conversion efficiencies. When used in conjunction with a sodium fast reactor, the supercritical CO{sub 2} cycle offers additional safety advantages by eliminating potential sodium-water interactions that may occur in a steam cycle. In power conversion systems for Generation IV fast reactors, supercritical CO{sub 2} temperatures could be in the range of 30°C to 650°C, depending on the specific component in the system. Materials corrosion primarily at high temperatures will be an important issue. Therefore, the corrosion performancemore » limits for materials at various temperatures must be established. The proposed research will have four objectives centered on addressing corrosion issues in a high-temperature supercritical CO{sub 2} environment: Task 1: Evaluation of corrosion performance of candidate alloys in high-purity supercritical CO{sub 2}: The following alloys will be tested: Ferritic-martensitic Steels NF616 and HCM12A, austenitic alloys Incoloy 800H and 347 stainless steel, and two advanced concept alloys, AFA (alumina forming austenitic) steel and MA754. Supercritical CO{sub 2} testing will be performed at 450°C, 550°C, and 650°C at a pressure of 20 MPa, in a test facility that is already in place at the proposing university. High purity CO{sub 2} (99.9998%) will be used for these tests. Task 2: Investigation of the effects of CO, H{sub 2}O, and O{sub 2} impurities in supercritical CO{sub 2} on corrosion: Impurities that will inevitably present in the CO{sub 2} will play a critical role in dictating the extent of corrosion and corrosion mechanisms. These effects must be understood to identify the level of CO{sub 2} chemistry control needed to maintain sufficient levels of purity to manage corrosion. The individual effects of important impurities CO, H{sub 2}O, and O{sub 2} will be investigated by adding them separately to high purity CO{sub 2}. Task 3: Evaluation of surface treatments on the corrosion performance of alloys in supercritical CO{sub 2}: Surface treatments can be very beneficial in improving corrosion resistance. Shot peening and yttrium and aluminum surface treatments will be investigated. Shot peening refines the surface grain sizes and promotes protective Cr-oxide layer formation. Both yttrium and aluminum form highly stable oxide layers (Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), which can get incorporated in the growing Fe-oxide layer to form an impervious complex oxide to enhance corrosion resistance. Task 4: Study of flow-assisted corrosion of select alloys in supercritical CO{sub 2} under a selected set of test conditions: To study the effects of flow-assisted corrosion, tests will be conducted in a supercritical CO{sub 2} flow loop. An existing facility used for supercritical water flow studies at the proposing university will be modified for use in this task. The system is capable of flow velocities up to 10 m/s and can operate at temperatures and pressures of up to 650°C and 20 MPa, respectively. All above tasks will be performed in conjunction with detailed materials characterization and analysis using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS), x-ray diffraction (XRD), Auger electron spectroscopy (AES) techniques, and weight change measurements. Inlet and outlet gas compositions will be monitored using gas chromatography-mass spectrometry (GCMS).« less

  2. Copper(II) catalysis in cyanide conversion into ethyl carbamate in spirits and relevant reactions.

    PubMed

    Aresta, M; Boscolo, M; Franco, D W

    2001-06-01

    The role of copper(II) species in the oxidation of inorganic cyanide to cyanate and in the conversion of cyanate or urea into ethyl carbamate was investigated. The oxidation process has been shown to be independent from the dissolved oxygen. Elemental analysis and infrared spectroscopy have shown the formation of a mixed copper carbonate/hydroxide in the process of oxidation of cyanide to cyanate in water/ethanol. The complexation to Cu(II) of cyanate formed upon cyanide oxidation makes the former more susceptible to nucleophilic attack from ethanol, with conversion into ethyl carbamate. Comparatively, urea has a minor role with respect to cyanide in the formation of ethyl carbamate. Therefore, the urea present in some samples of Brazilian sugar cane spirit (cachaça) has been shown to have almost no influence on the ethyl carbamate content of cachaças, which comes essentially from cyanide. Fe(II,III) affords results similar to those found with Cu(II). Some suggestions are presented to avoid ethyl carbamate formation in spirits during distillation.

  3. 40 CFR Table 2 to Subpart Fff of... - Nitrogen Oxides Requirements for Affected Facilities

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Nitrogen Oxides Requirements for Affected Facilities 2 Table 2 to Subpart FFF of Part 62 Protection of Environment ENVIRONMENTAL PROTECTION... Before September 20, 1994 Pt. 62, Subpt. FFF, Table 2 Table 2 to Subpart FFF of Part 62—Nitrogen Oxides...

  4. Evaluation of biochars by temperature programmed oxidation/mass spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Biochar from the thermochemical conversion of biomass was evaluated by Temperature Programmed Oxidation (TPO) coupled with mass spectroscopy. This technique can be used to assess the oxidative reactivity of carbonaceous solids where higher temperature reactivity indicates greater structural order. ...

  5. Discovering Inexpensive, Effective Catalysts for Solar Energy Conversion: An Authentic Research Laboratory Experience

    ERIC Educational Resources Information Center

    Shaner, Sarah E.; Hooker, Paul D.; Nickel, Anne-Marie; Leichtfuss, Amanda R.; Adams, Carissa S.; de la Cerda, Dionisia; She, Yuqi; Gerken, James B.; Pokhrel, Ravi; Ambrose, Nicholas J.; Khaliqi, David; Stahl, Shannon S.; Schuttlefield Christus, Jennifer D.

    2016-01-01

    Electrochemical water oxidation is a major focus of solar energy conversion efforts. A new laboratory experiment has been developed that utilizes real-time, hands-on research to discover catalysts for solar energy conversion. The HARPOON, or Heterogeneous Anodes Rapidly Perused for Oxygen Overpotential Neutralization, experiment allows an array of…

  6. Validation of gamma-ray detection techniques for safeguards monitoring at natural uranium conversion facilities

    DOE PAGES

    Dewji, Shaheen A.; Lee, Denise L.; Croft, Stephen; ...

    2016-03-28

    Recent IAEA circulars and policy papers have sought to implement safeguards when any purified aqueous uranium solution or uranium oxides suitable for isotopic enrichment or fuel fabrication exists. Under the revised policy, IAEA Policy Paper 18, the starting point for nuclear material under safeguards was reinterpreted, suggesting that purified uranium compounds should be subject to safeguards procedures no later than the first point in the conversion process. In response to this technical need, a combination of simulation models and experimental measurements were employed to develop and validate concepts of nondestructive assay monitoring systems in a natural uranium conversion plant (NUCP).more » In particular, uranyl nitrate (UO 2(NO 3) 2) solution exiting solvent extraction was identified as a key measurement point (KMP), where gamma-ray spectroscopy was selected as the process monitoring tool. The Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility at Oak Ridge National Laboratory was employed to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in an NUCP. Nondestructive assay techniques using gamma-ray spectroscopy were evaluated to determine their viability as a technical means for drawing safeguards conclusions at NUCPs, and if the IAEA detection requirements of 1 significant quantity (SQ) can be met in a timely way. This work investigated gamma-ray signatures of uranyl nitrate circulating in the UNCLE facility and evaluated various gamma-ray detector sensitivities to uranyl nitrate. These detector validation activities include assessing detector responses to the uranyl nitrate gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and high-purity germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10–90 g U/L of natural uranyl nitrate are presented. A range of gamma-ray lines is examined, including attenuation for transmission measurement of density and concentration. It was determined that transmission-corrected gamma-ray spectra provide a reliable way to monitor the 235U concentration of uranyl nitrate solution in transfer pipes in NUCPs. Furthermore, existing predictive and analysis methods are adequate to design and realize practical designs. The 137Cs transmission source employed in this work is viable but not optimal for 235U densitometry determination. Validated simulations assessed the viability of 133Ba and 57Co as alternative densitometry sources. All three gamma-ray detectors are viable for monitoring natural uranium feed; although high-purity germanium is easiest to interpret, it is, however, the least attractive as an installation instrument. Overall, for monitoring throughput in a facility such as UNCLE, emulating the uranium concentration and pump speeds of the Springfields conversion facility in the United Kingdom, an uncertainty of less than 0.17% is required in order to detect the diversion of 1 SQ of uranyl nitrate through changes in uranium concentration over an accountancy period of one year with a detection probability of 50%. As a result, calibrated gamma-ray detection systems are capable of determining the concentration of uranium content in NUCPs, it is only in combination with verifiable operator declarations and supporting data, such as flow rate and enrichment, that safeguards conclusions can be drawn.« less

  7. 43 CFR 3212.24 - How will the production incentive apply to a new facility?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) GEOTHERMAL... Royalty Rate Conversions § 3212.24 How will the production incentive apply to a new facility? (a) If BLM... electricity from the new facility. (b) The amount of the production incentive is established in MMS...

  8. 43 CFR 3212.24 - How will the production incentive apply to a new facility?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) GEOTHERMAL... Royalty Rate Conversions § 3212.24 How will the production incentive apply to a new facility? (a) If BLM... electricity from the new facility. (b) The amount of the production incentive is established in MMS...

  9. 43 CFR 3212.24 - How will the production incentive apply to a new facility?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) GEOTHERMAL... Royalty Rate Conversions § 3212.24 How will the production incentive apply to a new facility? (a) If BLM... electricity from the new facility. (b) The amount of the production incentive is established in MMS...

  10. Ethylene Oxide Emissions Standards for Sterilization Facilities: National Emission Standards for Hazardous Air Pollutants (NESHAP)

    EPA Pesticide Factsheets

    Learn about the NESHAP for ethylene oxide emissions for sterilization facilities. Find the rule history information, federal register citations, legal authority, and related rules as well as a rule summary.

  11. Thin film photovoltaic cells having increased durability and operating life and method for making same

    DOEpatents

    Barnett, Allen M.; Masi, James V.; Hall, Robert B.

    1980-12-16

    A solar cell having a copper-bearing absorber is provided with a composite transparent encapsulating layer specifically designed to prevent oxidation of the copper sulfide. In a preferred embodiment, the absorber is a layer of copper sulfide and the composite layer comprises a thin layer of copper oxide formed on the copper sulfide and a layer of encapsulating glass formed on the oxide. It is anticipated that such devices, when exposed to normal operating conditions of various terrestrial applications, can be maintained at energy conversion efficiencies greater than one-half the original conversion efficiency for periods as long as thirty years.

  12. Near-infrared light controlled photocatalytic activity of carbon quantum dots for highly selective oxidation reaction

    NASA Astrophysics Data System (ADS)

    Li, Haitao; Liu, Ruihua; Lian, Suoyuan; Liu, Yang; Huang, Hui; Kang, Zhenhui

    2013-03-01

    Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry.Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00092c

  13. Plutonium Finishing Plant (PFP) Final Safety Analysis Report (FSAR) [SEC 1 THRU 11

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    ULLAH, M K

    2001-02-26

    The Plutonium Finishing Plant (PFP) is located on the US Department of Energy (DOE) Hanford Site in south central Washington State. The DOE Richland Operations (DOE-RL) Project Hanford Management Contract (PHMC) is with Fluor Hanford Inc. (FH). Westinghouse Safety Management Systems (WSMS) provides management support to the PFP facility. Since 1991, the mission of the PFP has changed from plutonium material processing to preparation for decontamination and decommissioning (D and D). The PFP is in transition between its previous mission and the proposed D and D mission. The objective of the transition is to place the facility into a stablemore » state for long-term storage of plutonium materials before final disposition of the facility. Accordingly, this update of the Final Safety Analysis Report (FSAR) reflects the current status of the buildings, equipment, and operations during this transition. The primary product of the PFP was plutonium metal in the form of 2.2-kg, cylindrical ingots called buttoms. Plutonium nitrate was one of several chemical compounds containing plutonium that were produced as an intermediate processing product. Plutonium recovery was performed at the Plutonium Reclamation Facility (PRF) and plutonium conversion (from a nitrate form to a metal form) was performed at the Remote Mechanical C (RMC) Line as the primary processes. Plutonium oxide was also produced at the Remote Mechanical A (RMA) Line. Plutonium processed at the PFP contained both weapons-grade and fuels-grade plutonium materials. The capability existed to process both weapons-grade and fuels-grade material through the PRF and only weapons-grade material through the RMC Line although fuels-grade material was processed through the line before 1984. Amounts of these materials exist in storage throughout the facility in various residual forms left from previous years of operations.« less

  14. Reversible conversion of valence-tautomeric copper metal-organic frameworks dependent single-crystal-to-single-crystal oxidation/reduction: a redox-switchable catalyst for C-H bonds activation reaction.

    PubMed

    Huang, Chao; Wu, Jie; Song, Chuanjun; Ding, Ran; Qiao, Yan; Hou, Hongwei; Chang, Junbiao; Fan, Yaoting

    2015-06-28

    Upon single-crystal-to-single-crystal (SCSC) oxidation/reduction, reversible structural transformations take place between the anionic porous zeolite-like Cu(I) framework and a topologically equivalent neutral Cu(I)Cu(II) mixed-valent framework. The unique conversion behavior of the Cu(I) framework endowed it as a redox-switchable catalyst for the direct arylation of heterocycle C-H bonds.

  15. Development and Exploration of Nanoparticle Decorated Carbon Supports (Graphene and Graphene Oxide) for Energy Collection, Storage, and Conversion

    DTIC Science & Technology

    2012-12-17

    hybrid films as an alternative to organic-based photoactive materials in flexible photodetectors and solar cells . Figure 3. Solution...a wide range of metal nanoparticle-decorated (Pt, Au, Ag, Pt/Ru) graphene oxide (GO) hybrids as well as inorganic particle-graphene ( TiO2 /PbSe/G... hybrids . These hybrids were then evaluated for their performance in energy conversion devices and two examples were chosen, namely stacked fuel cells

  16. 47 CFR 27.1238 - Eligible costs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS...) Legal fees; (5) Site acquisition fees-contractor; and (6) Arbitrator fee; (c) Transmission facility... manage the BTA conversion); and (10) Travel and Per Diem Cost. (d) Transmission facility-digital...

  17. 47 CFR 27.1238 - Eligible costs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS...) Legal fees; (5) Site acquisition fees-contractor; and (6) Arbitrator fee; (c) Transmission facility... manage the BTA conversion); and (10) Travel and Per Diem Cost. (d) Transmission facility-digital...

  18. 47 CFR 27.1238 - Eligible costs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS...) Legal fees; (5) Site acquisition fees-contractor; and (6) Arbitrator fee; (c) Transmission facility... manage the BTA conversion); and (10) Travel and Per Diem Cost. (d) Transmission facility-digital...

  19. 47 CFR 27.1238 - Eligible costs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS...) Legal fees; (5) Site acquisition fees-contractor; and (6) Arbitrator fee; (c) Transmission facility... manage the BTA conversion); and (10) Travel and Per Diem Cost. (d) Transmission facility-digital...

  20. Uranium Conversion & Enrichment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karpius, Peter Joseph

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U 3O 8 yellowcake into UF 6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  1. Graphitic carbon nitride (g-C3N4) coated titanium oxide nanotube arrays with enhanced photo-electrochemical performance.

    PubMed

    Sun, Mingxuan; Fang, Yalin; Kong, Yuanyuan; Sun, Shanfu; Yu, Zhishui; Umar, Ahmad

    2016-08-09

    Herein, we report the successful formation of graphitic carbon nitride coated titanium oxide nanotube array thin films (g-C3N4/TiO2) via the facile thermal treatment of anodized Ti sheets over melamine. The proportion of C3N4 and TiO2 in the composite can be adjusted by changing the initial addition mass of melamine. The as-prepared samples are characterized by several techniques in order to understand the morphological, structural, compositional and optical properties. UV-vis absorption studies exhibit a remarkable red shift for the g-C3N4/TiO2 thin films as compared to the pristine TiO2 nanotubes. Importantly, the prepared composites exhibit an enhanced photocurrent and photo-potential under both UV-vis and visible light irradiation. Moreover, the observed maximum photo-conversion efficiency of the prepared composites is 1.59 times higher than that of the pristine TiO2 nanotubes. The optical and electrochemical impedance spectra analysis reveals that the better photo-electrochemical performance of the g-C3N4/TiO2 nanotubes is mainly due to the wider light absorption and reduced impedance compared to the bare TiO2 nanotube electrode. The presented work demonstrates a facile and simple method to fabricate g-C3N4/TiO2 nanotubes and clearly revealed that the introduction of g-C3N4 is a new and innovative approach to improve the photocurrent and photo-potential efficiencies of TiO2.

  2. Production of highly tritiated water for tritium exposure studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muirhead, C.; Pilatzke, K.; Tripple, A.

    2015-03-15

    Tritium Facility staff at Chalk River Laboratories (CRL) have successfully prepared highly tritiated water for use in radiation resistance of PEM (Proton Exchange Membrane-based)electrolyser membrane. The goal of System A was to convert a known amount of elemental tritium (HT) into tritiated water vapour using a copper(II) oxide bed, and to condense the tritiated water vapour into a known amount of chilled heavy water (D{sub 2}O). The conversion and capture of tritium using this system is close to 100%. The goal of System B was to transfer tritiated water from the containment vessel to an exposure vessel (experiment) in amore » controlled and safe manner. System B is based on the pushing of D{sub 2}0 with low-pressure argon carrier gas to a calibrated volume and then to the exposure vessel. A method for delivering a known and controlled amount of tritiated water has been successfully demonstrated at CRL. Using both systems Tritium Facility staff have made and distributed highly tritiated water in a safe and controlled manner. This paper focuses on how the tritiated water was produced and dispensed to the experiment.« less

  3. Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Run 260 with Black Thunder Mine subbituminous coal: Technical progress report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    This report presents the results of Run 260 performed at the Advanced Coal Liquefaction R&D Facility in Wilsonville. The run was started on July 17, 1990 and continued until November 14, 1990, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Black Thunder mine subbituminous coal (Wyodak-Anderson seam from Wyoming Powder River Basin). Both thermal/catalytic and catalytic/thermal tests were performed to determine the methods for reducing solids buildup in a subbituminous coal operation, and to improve product yields. A new, smaller interstage separator was tested to reduce solids buildup by increasing the slurry space velocity in the separator. In ordermore » to obtain improved coal and resid conversions (compared to Run 258) full-volume thermal reactor and 3/4-volume catalytic reactor were used. Shell 324 catalyst, 1/16 in. cylindrical extrudate, at a replacement rate of 3 lb/ton of MF coal was used in the catalytic stage. Iron oxide was used as slurry catalyst at a rate of 2 wt % MF coal throughout the run. (TNPS was the sulfiding agent.)« less

  4. Estimating historical respirable crystalline silica exposures for Chinese pottery workers and iron/copper, tin, and tungsten miners.

    PubMed

    Zhuang, Z; Hearl, F J; Odencrantz, J; Chen, W; Chen, B T; Chen, J Q; McCawley, M A; Gao, P; Soderholm, S C

    2001-11-01

    Collaborative studies of Chinese workers, using over four decades of dust monitoring data, are being conducted by the National Institute for Occupational Safety and Health (NIOSH) and Tongji Medical University in China. The goal of these projects is to establish exposure-response relationships for the development of diseases such as silicosis or lung cancer in cohorts of pottery and mine workers. It is necessary to convert Chinese dust measurements to respirable silica measurements in order to make results from the Chinese data comparable to other results in the literature. This article describes the development of conversion factors and estimates of historical respirable crystalline silica exposure for Chinese workers. Ambient total dust concentrations (n>17000) and crystalline silica concentrations (n=347) in bulk dust were first gathered from historical industrial hygiene records. Analysis of the silica content in historical bulk samples revealed no trend from 1950 up to the present. During 1988-1989, side-by-side airborne dust samples (n=143 pairs) were collected using nylon cyclones and traditional Chinese samplers in 20 metal mines and nine pottery factories in China. These data were used to establish conversion factors between respirable crystalline silica concentrations and Chinese total dust concentrations. Based on the analysis of the available evidence, conversion factors derived from the 1988-1989 sampling campaign are assumed to apply to other time periods in this paper. The conversion factors were estimated to be 0.0143 for iron/copper, 0.0355 for pottery factories, 0.0429 for tin mines, and 0.0861 for tungsten mines. Conversion factors for individual facilities within each industry were also calculated. Analysis of variance revealed that mean conversion factors are significantly different among facilities within the iron/copper industry and within the pottery industry. The relative merits of using facility-specific conversion factors, industry-wide conversion factors, or a weighted average of the two are discussed. The exposure matrix of the historical Chinese total dust concentrations was multiplied by these conversion factors to obtain an exposure matrix of historical respirable crystalline silica concentrations.

  5. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

    PubMed Central

    Wickman, B.; Bastos Fanta, A.; Burrows, A.; Hellman, A.; Wagner, J. B.; Iandolo, B.

    2017-01-01

    Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation. These films show the largest average grain size and the highest charge carrier density, as determined from electron microscopy and impedance spectroscopy analysis. We believe that the fast processing enabled by RTP makes this technique a preferred method for investigation of novel materials and architectures, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance. PMID:28091573

  6. Carbon catalyzed SO2 oxidation by NO2 and O3

    NASA Technical Reports Server (NTRS)

    Cofer, W. R., III; Schryer, D. R.; Rogowski, R. S.

    1982-01-01

    The oxidation of SO2 to sulfate on carbon particles by trace quantities of NO2 and O3 was studied. Particulate carbon black was either: (1) directly exposed on the pan of a microbalance to various humidified mixtures of SO2 and oxidant gas and the resultant weight gains monitored, or (2) the gas mixtures were bubbled through aqueous suspensions of carbon black and pure water blanks. In each set of experiments the run times were varied appropriately and the yields of sulfate were determined analytically. Conversion of SO2 to sulfate was thus characterized as a function of exposure time and of oxidant gas. Carbon black was determined to be an excellent catalyst for SO2 oxidation to sulfate by both NO2 and O3. No saturation effects were observed in either experimental approach. Conversions of SO2 to sulfate did not appear pH dependent.

  7. NNSA B-Roll: MOX Facility

    ScienceCinema

    None

    2017-12-09

    In 1999, the National Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

  8. NNSA B-Roll: MOX Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2010-05-21

    In 1999, the National Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

  9. Developing depleted uranium and gold cocktail hohlraums for the National Ignition Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilkens, H. L.; Nikroo, A.; Wall, D. R.

    2007-05-15

    Fusion ignition experiments are planned to begin at the National Ignition Facility (NIF) [J. A. Paisner, E. M. Campbell, and W. J. Hogan, Fusion Technol. 26, 755 (1994)] using the indirect drive configuration [J. D. Lindl, P. Amendt, R. L. Berger, S. G. Glendinning, S. H. Glenzer, S. W. Haan, R. L, Kauffman, O. L. Landen, and L. J. Suter, Phys. Plasmas 11, 339 (2004)]. Although the x-ray drive in this configuration is highly symmetric, energy is lost in the conversion process due to x-ray penetration into the hohlraum wall. To mitigate this loss, depleted uranium is incorporated into themore » traditional gold hohlraum to increase the efficiency of the laser to x-ray energy conversion by making the wall more opaque to the x rays [H. Nishumura, T. Endo, H. Shiraga, U. Kato, and S. Nakai, Appl. Phys. Lett. 62, 1344 (1993)]. Multilayered depleted uranium (DU) and gold hohlraums are deposited by sputtering by alternately rotating a hohlraum mold in front of separate DU and Au sources to build up multilayers to the desired wall thickness. This mold is removed to leave a freestanding hohlraum half; two halves are used to assemble the complete NIF hohlraum to the design specifications. In practice, exposed DU oxidizes in air and other chemicals necessary to hohlraum production, so research has focused on developing a fabrication process that protects the U from damaging environments. This paper reports on the most current depleted uranium and gold cocktail hohlraum fabrication techniques, including characterization by Auger electron spectroscopy, which is used to verify sample composition and the amount of oxygen uptake over time.« less

  10. Oxidation of anthracene using waste Mn oxide minerals: the importance of wetting and drying sequences.

    PubMed

    Clarke, Catherine; Tourney, Janette; Johnson, Karen

    2012-02-29

    PAHs are a common problem in contaminated urban soils due to their recalcitrance. This study presents results on the oxidation of anthracene on synthetic and natural Mn oxide surfaces. Evaporation of anthracene spiked Mn oxide slurries in air results in the oxidation of 30% of the anthracene to anthraquinone. Control minerals, quartz and calcite, also oxidised a small but significant proportion of the anthracene (4.5% and 14% conversion, respectively) when spiked mineral slurries were evaporated in air. However, only Mn oxide minerals showed significant anthracene oxidation (5-10%) when evaporation took place in the absence of oxygen (N2 atmosphere). In the fully hydrated systems where no drying took place, natural Mn oxides showed an increase in anthracene oxidation with decreasing pH, with a conversion of 75% anthracene at pH 4. These results show both acidification and drying favor the oxidation of anthracene on Mn oxide mineral surfaces. It has also been demonstrated that non-redox active mineral surfaces, such as calcite, may play a role in contaminant breakdown during wetting and drying sequences. Given that climate changes suggest that wetting and drying sequences are likely to become more significant these results have important implications for contaminated land remediation technologies. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. 75 FR 81337 - Interim Final Regulation Deferring the Reporting Date for Certain Data Elements Required Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... Meat processing facilities. 311411 Frozen fruit, juice, and vegetable manufacturing facilities. 311421... volume conversion factor. Y 98.256(m)(3) Only total quantity of crude oil plus the quantity of...

  12. Surface Characterization of Mesoporous CoOx/SBA-15 Catalyst upon 1,2-Dichloropropane Oxidation.

    PubMed

    Finocchio, Elisabetta; Gonzalez-Prior, Jonatan; Gutierrez-Ortiz, Jose Ignacio; Lopez-Fonseca, Ruben; Busca, Guido; de Rivas, Beatriz

    2018-05-29

    The active combustion catalyst that is based on 30 wt % cobalt oxide on mesoporous SBA-15 has been tested in 1,2-dichloropropane oxidation and is characterized by means of FT-IR (Fourier transform infrared spectroscopy) and ammonia-TPD (temperature-programmed desorption). In this work, we report the spectroscopic evidence for the role of surface acidity in chloroalkane conversion. Both Lewis acidity and weakly acidic silanol groups from SBA support are involved in the adsorption and initial conversion steps. Moreover, total oxidation reaction results in the formation of new Bronsted acidic sites, which are likely associated with the generation of HCl at high temperature and its adsorption at the catalyst surface. Highly dispersed Co oxide on the mesoporous support and Co-chloride or oxychloride particles, together with the presence of several families of acidic sites originated from the conditioning effect of reaction products may explain the good activity of this catalyst in the oxidation of Chlorinated Volatile Organic Compounds.

  13. 36 CFR 59.3 - Conversion requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... not been dedicated or managed for recreation/conservation use may be used as replacement land even if... proposed conversion and substitution constitute significant changes to the original Land and Water... approval is not necessarily required, however, for each and every facility use change. Rather, a project...

  14. Innovative practice: Conversational use of English in bilingual adults with dementia.

    PubMed

    Kokorelias, Kristina M; Ryan, Ellen B; Elliot, Gail

    2017-02-01

    Regression to mother tongue is common in those with dementia. In two long-term care facilities, we explored the use of bilinguals' two languages for five older adults with mild-moderate dementia who have begun to regress to Greek. We also examined the role of Montessori DementiAbility Methods: The Montessori Way-based English language activities in fostering conversational use of English. Over 10 sessions, participants' vocabulary or grammatical structure in English did not improve. However, four of the five participants were able to maintain a conversation in English for longer periods of time. This study contributes to strategies for optimizing meaningful conversation for bilingual long-term care residents with dementia. Moreover, the data suggest a change in the policy and practice for dementia care so that there are more opportunities for residents to speak English in non-English mother-tongue facilities. Greater attention to the specific language needs of bilinguals in English-dominant settings would also be advisable.

  15. Solvothermal one-step synthesis of Ni-Al layered double hydroxide/carbon nanotube/reduced graphene oxide sheet ternary nanocomposite with ultrahigh capacitance for supercapacitors.

    PubMed

    Yang, Wanlu; Gao, Zan; Wang, Jun; Ma, Jing; Zhang, Milin; Liu, Lianhe

    2013-06-26

    A Ni-Al layered double hydroxide (LDH), mutil-wall carbon nanotube (CNT), and reduced graphene oxide sheet (GNS) ternary nanocomposite electrode material has been developed by a facile one-step ethanol solvothermal method. The obtained LDH/CNT/GNS composite displayed a three-dimensional (3D) architecture with flowerlike Ni-Al LDH/CNT nanocrystallites gradually self-assembled on GNS nanosheets. GNS was used as building blocks to construct 3D nanostructure, and the LDH/CNT nanoflowers in turn separated the two-dimensional (2D) GNS sheets, which preserved the high surface area of GNSs. Furthermore, the generated porous networks with a narrow pore size distribution in the LDH/CNT/GNS composite were also demonstrated by the N2 adsorption/desorption experiment. Such morphology would be favorable to improve the mass transfer and electrochemical action of the electrode. As supercapacitor electrode material, the LDH/CNT/GNS hybrid exhibited excellent electrochemical performance, including ultrahigh specific capacitance (1562 F/g at 5 mA/cm(2)), excellent rate capability, and long-term cycling performance, which could be a promising energy storage/conversion material for supercapacitor application.

  16. Solution-processed highly conductive PEDOT:PSS/AgNW/GO transparent film for efficient organic-Si hybrid solar cells.

    PubMed

    Xu, Qiaojing; Song, Tao; Cui, Wei; Liu, Yuqiang; Xu, Weidong; Lee, Shuit-Tong; Sun, Baoquan

    2015-02-11

    Hybrid solar cells based on n-Si/poly(3,4-ethylenedioxythiophene):poly(styrene- sulfonate) (PEDOT:PSS) heterojunction promise to be a low cost photovoltaic technology by using simple device structure and easy fabrication process. However, due to the low conductivity of PEDOT:PSS, a metal grid deposited by vacuum evaporation method is still required to enhance the charge collection efficiency, which complicates the device fabrication process. Here, a solution-processed graphene oxide (GO)-welded silver nanowires (AgNWs) transparent conductive electrode (TCE) was employed to replace the vacuum deposited metal grid. A unique "sandwich" structure was developed by embedding an AgNW network between PEDOT:PSS and GO with a figure-of-merit of 8.6×10(-3) Ω(-1), which was even higher than that of sputtered indium tin oxide electrode (6.6×10(-3) Ω(-1)). A champion power conversion efficiency of 13.3% was achieved, because of the decreased series resistance of the TCEs as well as the enhanced built-in potential (Vbi) in the hybrid solar cells. The TCEs were obtained by facile low-temperature solution process method, which was compatible with cost-effective mass production technology.

  17. Low work function materials for microminiature energy conversion and recovery applications

    DOEpatents

    Zavadil, Kevin R.; Ruffner, Judith A.; King, Donald B.

    2003-05-13

    Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties. In the preferred embodiment, the individual layers include mixed BaSrCaO, scandium oxide and tungsten.

  18. Facile Approach to Preparing a Vanadium Oxide Hydrate Layer as a Hole-Transport Layer for High-Performance Polymer Solar Cells.

    PubMed

    Cong, Hailin; Han, Dongwei; Sun, Bingbing; Zhou, Dongying; Wang, Chen; Liu, Ping; Feng, Lai

    2017-05-31

    We demonstrate a facile and green approach to preparing a vanadium oxide hydrate (VO x ·nH 2 O) layer to serve as the hole-transport layer (HTL) in high-performance polymer solar cells (PSCs). The VO x ·nH 2 O layer was in situ prepared by a combined H 2 O 2 and ultraviolet-ozone (UVO) processing on a VO x layer. The as-prepared VO x ·nH 2 O layer featured a work function of 5.0 ± 0.1 eV, high transmittance, and better interface properties compared to those of the generally prepared VO x (UVO or thermal annealing) layers. PSCs based on poly[(ethylhexyl-thiophenyl)-benzodithiophene-(ethylhexyl)-thienothiophene]/[6,6]-phenyl-C 71 -butyric acid methyl ester using the VO x ·nH 2 O layer as the HTL yielded high power conversion efficiencies (PCEs) up to 8.11%, outperforming the devices with VO x layers (PCE of 6.79% for the UVO-processed VO x layer and 6.10% for the thermally annealed VO x layer) and conventional polyethylenedioxythiophene-polystyrenesulfonate (PEDOT:PSS) layers (PCE of 7.67%). The improved PCE was attributed to the enhanced J SC and/or fill factor, which mainly correlate to the improved interfacial contact between the photoactive layer and the indium tin oxide/HTL or cathode when using the VO x ·nH 2 O layer as the HTL. A similar improvement in the PCE was also observed for the PSCs based on poly(3-hexylthiophene)/[6,6]-phenyl-C 61 -butyric acid methyl ester. In addition, PSCs with a VO x ·nH 2 O layer as the HTL showed a higher stability than that of those with a PEDOT:PSS layer. Hence, it would be possible to use this simply and in situ prepared VO x ·nH 2 O layer as an inexpensive HTL for high-performance PSCs.

  19. Ruthenium-catalyzed alkylation of indoles with tertiary amines by oxidation of a sp3 C-H bond and Lewis acid catalysis.

    PubMed

    Wang, Ming-Zhong; Zhou, Cong-Ying; Wong, Man-Kin; Che, Chi-Ming

    2010-05-17

    Ruthenium porphyrins (particularly [Ru(2,6-Cl(2)tpp)CO]; tpp=tetraphenylporphinato) and RuCl(3) can act as oxidation and/or Lewis acid catalysts for direct C-3 alkylation of indoles, giving the desired products in high yields (up to 82% based on 60-95% substrate conversions). These ruthenium compounds catalyze oxidative coupling reactions of a wide variety of anilines and indoles bearing electron-withdrawing or electron-donating substituents with high regioselectivity when using tBuOOH as an oxidant, resulting in the alkylation of N-arylindoles to 3-{[(N-aryl-N-alkyl)amino]methyl}indoles (yield: up to 82%, conversion: up to 95%) and the alkylation of N-alkyl or N-H indoles to 3-[p-(dialkylamino)benzyl]indoles (yield: up to 73%, conversion: up to 92%). A tentative reaction mechanism involving two pathways is proposed: an iminium ion intermediate may be generated by oxidation of an sp(3) C-H bond of the alkylated aniline by an oxoruthenium species; this iminium ion could then either be trapped by an N-arylindole (pathway A) or converted to formaldehyde, allowing a subsequent three-component coupling reaction of the in situ generated formaldehyde with an N-alkylindole and an aniline in the presence of a Lewis acid catalyst (pathway B). The results of deuterium-labeling experiments are consistent with the alkylation of N-alkylindoles via pathway B. The relative reaction rates of [Ru(2,6-Cl(2)tpp)CO]-catalyzed oxidative coupling reactions of 4-X-substituted N,N-dimethylanilines with N-phenylindole (using tBuOOH as oxidant), determined through competition experiments, correlate linearly with the substituent constants sigma (R(2)=0.989), giving a rho value of -1.09. This rho value and the magnitudes of the intra- and intermolecular deuterium isotope effects (k(H)/k(D)) suggest that electron transfer most likely occurs during the initial stage of the oxidation of 4-X-substituted N,N-dimethylanilines. Ruthenium-catalyzed three-component reaction of N-alkyl/N-H indoles, paraformaldehyde, and anilines gave 3-[p-(dialkylamino)benzyl]indoles in up to 82% yield (conversion: up to 95%).

  20. Commercialization of waste gob gas and methane produced in conjunction with coal mining operations. Final report, August 1992--December 1993

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1993-12-01

    The primary objectives of the project were to identify and evaluate existing processes for (1) using gas as a feedstock for production of marketable, value-added commodities, and (2) enriching contaminated gas to pipeline quality. The following gas conversion technologies were evaluated: (1) transformation to liquid fuels, (2) manufacture of methanol, (3) synthesis of mixed alcohols, and (4) conversion to ammonia and urea. All of these involved synthesis gas production prior to conversion to the desired end products. Most of the conversion technologies evaluated were found to be mature processes operating at a large scale. A drawback in all of themore » processes was the need to have a relatively pure feedstock, thereby requiring gas clean-up prior to conversion. Despite this requirement, the conversion technologies were preliminarily found to be marginally economic. However, the prohibitively high investment for a combined gas clean-up/conversion facility required that REI refocus the project to investigation of gas enrichment alternatives. Enrichment of a gas stream with only one contaminant is a relatively straightforward process (depending on the contaminant) using available technology. However, gob gas has a unique nature, being typically composed of from constituents. These components are: methane, nitrogen, oxygen, carbon dioxide and water vapor. Each of the four contaminants may be separated from the methane using existing technologies that have varying degrees of complexity and compatibility. However, the operating and cost effectiveness of the combined system is dependent on careful integration of the clean-up processes. REI is pursuing Phase 2 of this project for demonstration of a waste gas enrichment facility using the approach described above. This is expected to result in the validation of the commercial and technical viability of the facility, and the refinement of design parameters.« less

  1. Oxidation Numbers in the Study of Metabolism

    ERIC Educational Resources Information Center

    Bentley, Ronald; Franzen, James; Chasteen, Thomas G.

    2002-01-01

    The calculation and use of oxidation numbers in the study of metabolic reactions are discussed for normal oxidations (alcohol dehydrogenase and the NAD+/NADH couple, propanediol dehydratase) and for enzymatic reactions with a "hidden" redox component (transamination, the coupled conversion of ethylamine to ethanol, and the biomethylation of…

  2. THE RELATIONSHIP BETWEEN THE CORROSION OF DISTRIBUTION SYSTEM MATERIALS, AND OXIDANT AND REDOX POTENTIAL

    EPA Science Inventory

    Scale build-up, corrosion rate, and metal release associated with drinking water distribution system pipes have been suggested to relate to the oxidant type and concentration. Conversely, different distribution system metals may exert different oxidant demands. The impact of ox...

  3. Evaluation of biochars by temperature programmed oxidation/mass spectrometry

    Treesearch

    Michael Jackson; Thomas Eberhardt; Akwasi Boateng; Charles Mullen; Les Groom

    2013-01-01

    Biochars produced from thermochemical conversions of biomass were evaluated by temperature programmed oxidation (TPO). This technique, used to characterize carbon deposits on petroleum cracking catalysts, provides information on the oxidative stability of carbonaceous solids, where higher temperature reactivity indicates greater structural order, an important property...

  4. Biogasification of Walt Disney World biomass waste blend. Annual report Jan-Dec 82

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biljetina, R.; Chynoweth, D.P.; Janulis, J.

    1983-05-01

    The objective of this research is to develop efficient processes for conversion of biomass-waste blends to methane and other resources. To evaluate the technical and economic feasibility, an experimental test facility (ETU) is being designed and installed at the Reedy Creek Wastewater Treatment Plant at Walt Disney World, Orlando, Florida. The facility will integrate a biomethanogenic conversion process with a waste-water treatment process employing water hyacinth ponds for secondary and tertiary treatment of sewage produced at Walt Disney World. The ETU will be capable of feeding 1-wet ton per day of water hyacinth-sludge blends to the digestion system for productionmore » of methane and other byproducts. The detailed design of the facility has been completed and procurement of equipment is in progress.« less

  5. Symposium on the Physical Chemistry of Solar Energy Conversion, Indianapolis American Chemical Society Meetings, Fall 2013

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lian, Tianquan

    2013-09-20

    The Symposium on the Physical Chemistry of Solar Energy Conversion at the Fall ACS Meeting in Indianapolis, IN (Sept. 8-12) featured the following sessions (approx. 6 speakers per session): (1) Quantum Dots and Nanorods for Solar Energy Conversion (2 half-day sessions); (2) Artificial Photosynthesis: Water Oxidation; (3) Artificial Photosynthesis: Solar Fuels (2 half-day sessions); (4) Organic Solar Cells; (5) Novel Concepts for Solar Energy Conversion (2 half-day sessions); (6) Emerging Techniques for Solar Energy Conversion; (7) Interfacial Electron Transfer

  6. 40 CFR 232.3 - Activities not requiring permits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... buildings, roads, and other discrete structures and the installation of support facilities necessary for... structures used to effect such conversion. A conversion of section 404 wetland to a non-wetland is a change... emergency reconstruction of recently damaged parts, of currently serviceable structures such as dikes, dams...

  7. 40 CFR 232.3 - Activities not requiring permits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... buildings, roads, and other discrete structures and the installation of support facilities necessary for... structures used to effect such conversion. A conversion of section 404 wetland to a non-wetland is a change... emergency reconstruction of recently damaged parts, of currently serviceable structures such as dikes, dams...

  8. 40 CFR 232.3 - Activities not requiring permits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... buildings, roads, and other discrete structures and the installation of support facilities necessary for... structures used to effect such conversion. A conversion of section 404 wetland to a non-wetland is a change... emergency reconstruction of recently damaged parts, of currently serviceable structures such as dikes, dams...

  9. 40 CFR 232.3 - Activities not requiring permits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... buildings, roads, and other discrete structures and the installation of support facilities necessary for... structures used to effect such conversion. A conversion of section 404 wetland to a non-wetland is a change... emergency reconstruction of recently damaged parts, of currently serviceable structures such as dikes, dams...

  10. Stabilization of ultrathin (hydroxy)oxide films on transition metal substrates for electrochemical energy conversion

    DOE PAGES

    Zeng, Zhenhua; Chang, Kee-Chul; Kubal, Joseph; ...

    2017-05-08

    Design of cost-effective electrocatalysts with enhanced stability and activity is of paramount importance for the next generation of energy conversion systems, including fuel cells and electrolyzers. However, electrocatalytic materials generally improve one of these properties at the expense of the other. Here, using Density Functional Theory calculations and electrochemical surface science measurements, we explore atomic-level features of ultrathin (hydroxy)oxide films on transition metal substrates and demonstrate that these films exhibit both excellent stability and activity for electrocatalytic applications. The films adopt structures with stabilities that significantly exceed bulk Pourbaix limits, including stoichiometries not found in bulk and properties that aremore » tunable by controlling voltage, film composition, and substrate identity. Using nickel (hydroxy)oxide/Pt(111) as an example, we further show how the films enhance activity for hydrogen evolution through a bifunctional effect. Finally, the results suggest design principles for a new class of electrocatalysts with simultaneously enhanced stability and activity for energy conversion.« less

  11. Stabilization of ultrathin (hydroxy)oxide films on transition metal substrates for electrochemical energy conversion

    NASA Astrophysics Data System (ADS)

    Zeng, Zhenhua; Chang, Kee-Chul; Kubal, Joseph; Markovic, Nenad M.; Greeley, Jeffrey

    2017-06-01

    Design of cost-effective electrocatalysts with enhanced stability and activity is of paramount importance for the next generation of energy conversion systems, including fuel cells and electrolysers. However, electrocatalytic materials generally improve one of these properties at the expense of the other. Here, using density functional theory calculations and electrochemical surface science measurements, we explore atomic-level features of ultrathin (hydroxy)oxide films on transition metal substrates and demonstrate that these films exhibit both excellent stability and activity for electrocatalytic applications. The films adopt structures with stabilities that significantly exceed bulk Pourbaix limits, including stoichiometries not found in bulk and properties that are tunable by controlling voltage, film composition, and substrate identity. Using nickel (hydroxy)oxide/Pt(111) as an example, we further show how the films enhance activity for hydrogen evolution through a bifunctional effect. The results suggest design principles for this class of electrocatalysts with simultaneously enhanced stability and activity for energy conversion.

  12. Facile fabrication of all-solid-state SnO2/NiCo2O4 biosensor for self-powered glucose detection

    NASA Astrophysics Data System (ADS)

    Cai, Bin; Mao, Weiwei; Ye, Zhizhen; Huang, Jingyun

    2016-09-01

    With increasing attention on daily diabetes management, we develop an all-solid-state self-powered glucose biosensor, with simultaneous solar energy conversion, electrochemical energy storage and glucose sensing. The SnO2 nanosheet arrays are used to obtain photogenerated electron-hole pairs, and rhombus-shaped NiCo2O4 nanorod arrays are developed for solar energy storage. A stable open circuit voltage ~0.58 V is obtained after being fully charged, which is a suitable voltage for the oxidation of glucose. The biosensor can work under two different modes without any external bias voltage, and both show large linear range and excellent selectivity. Under the sunlight, photocurrent shows a sensitive decrease upon different glucose additions. Meanwhile, in the dark condition, the open circuit voltage of the charged biosensor also exhibits a corresponding response to glucose.

  13. Fe2O3 hollow sphere nanocomposites for supercapacitor applications

    NASA Astrophysics Data System (ADS)

    Zhao, Yu; Wen, Yang; Xu, Bing; Lu, Lu; Ren, Reiming

    2018-02-01

    Nanomaterials have attracted increasing interest in electrochemical energy storage and conversion. Hollow sphere Fe2O3 nanocomposites were successfully prepared through facile low temperature water-bath method with carbon sphere as hard template. The morphology and microstructure of samples were characterized by X-ray diffraction (XRD) and Scanning electron microscope (SEM), respectively. Through hydrolysis mechanism, using ferric chloride direct hydrolysis, iron hydroxide coated on the surface of carbon sphere, after high temperature calcination can form the hollow spherical iron oxide materials. Electrochemical performances of the hollow sphere Fe2O3 nanocomposites electrodes were investigated by cyclic voltammery (CV) and galvanostatic charge/discharge. The Pure hollow sphere Fe2O3 nanocomposites achieves a specific capacitance of 125 F g-1 at the current density of 85 mA g-1. The results indicate that the uniform dispersion of hollow ball structure can effectively reduce the particle reunion in the process of charging and discharging.

  14. Polymer-metal hybrid transparent electrodes for flexible electronics

    NASA Astrophysics Data System (ADS)

    Kang, Hongkyu; Jung, Suhyun; Jeong, Soyeong; Kim, Geunjin; Lee, Kwanghee

    2015-03-01

    Despite nearly two decades of research, the absence of ideal flexible and transparent electrodes has been the largest obstacle in realizing flexible and printable electronics for future technologies. Here we report the fabrication of ‘polymer-metal hybrid electrodes’ with high-performance properties, including a bending radius <1 mm, a visible-range transmittance>95% and a sheet resistance <10 Ω sq-1. These features arise from a surface modification of the plastic substrates using an amine-containing nonconjugated polyelectrolyte, which provides ideal metal-nucleation sites with a surface-density on the atomic scale, in combination with the successive deposition of a facile anti-reflective coating using a conducting polymer. The hybrid electrodes are fully functional as universal electrodes for high-end flexible electronic applications, such as polymer solar cells that exhibit a high power conversion efficiency of 10% and polymer light-emitting diodes that can outperform those based on transparent conducting oxides.

  15. Polymer-metal hybrid transparent electrodes for flexible electronics

    PubMed Central

    Kang, Hongkyu; Jung, Suhyun; Jeong, Soyeong; Kim, Geunjin; Lee, Kwanghee

    2015-01-01

    Despite nearly two decades of research, the absence of ideal flexible and transparent electrodes has been the largest obstacle in realizing flexible and printable electronics for future technologies. Here we report the fabrication of ‘polymer-metal hybrid electrodes’ with high-performance properties, including a bending radius <1 mm, a visible-range transmittance>95% and a sheet resistance <10 Ω sq−1. These features arise from a surface modification of the plastic substrates using an amine-containing nonconjugated polyelectrolyte, which provides ideal metal-nucleation sites with a surface-density on the atomic scale, in combination with the successive deposition of a facile anti-reflective coating using a conducting polymer. The hybrid electrodes are fully functional as universal electrodes for high-end flexible electronic applications, such as polymer solar cells that exhibit a high power conversion efficiency of 10% and polymer light-emitting diodes that can outperform those based on transparent conducting oxides. PMID:25790133

  16. Atmospheric pressure plasma analysis by modulated molecular beam mass spectrometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aranda Gonzalvo, Y.; Whitmore, T.D.; Rees, J.A.

    Fractional number density measurements for a rf plasma 'needle' operating at atmospheric pressure have been obtained using a molecular beam mass spectrometer (MBMS) system designed for diagnostics of atmospheric plasmas. The MBMS system comprises three differentially pumped stages and a mass/energy analyzer and includes an automated beam-to-background measurement facility in the form of a software-controlled chopper mechanism. The automation of the beam modulation allows the neutral components in the plasma to be rapidly and accurately measured using the mass spectrometer by threshold ionization techniques. Data are reported for plasma generated by a needle plasma source operated using a helium/air mixture.more » In particular, data for the conversion of atmospheric oxygen and nitrogen into nitric oxide are discussed with reference to its significance for medical applications such as disinfecting wounds and dental cavities and for microsurgery.« less

  17. Electrical power systems for Mars

    NASA Technical Reports Server (NTRS)

    Giudici, Robert J.

    1986-01-01

    Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

  18. Electrical power systems for Mars

    NASA Astrophysics Data System (ADS)

    Giudici, Robert J.

    1986-05-01

    Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

  19. Biotic conversion of sulphate to sulphide and abiotic conversion of sulphide to sulphur in a microbial fuel cell using cobalt oxide octahedrons as cathode catalyst.

    PubMed

    Chatterjee, Pritha; Ghangrekar, M M; Rao, Surampalli; Kumar, Senthil

    2017-05-01

    Varying chemical oxygen demand (COD) and sulphate concentrations in substrate were used to determine reaction kinetics and mass balance of organic matter and sulphate transformation in a microbial fuel cell (MFC). MFC with anodic chamber volume of 1 L, fed with wastewater having COD of 500 mg/L and sulphate of 200 mg/L, could harvest power of 54.4 mW/m 2 , at a Coulombic efficiency of 14%, with respective COD and sulphate removals of 90 and 95%. Sulphide concentration, even up to 1500 mg/L, did not inhibit anodic biochemical reactions, due to instantaneous abiotic oxidation to sulphur, at high inlet sulphate. Experiments on abiotic oxidation of sulphide to sulphur revealed maximum oxidation taking place at an anodic potential of -200 mV. More than 99% sulphate removal could be achieved in a MFC with inlet COD/sulphate of 0.75, giving around 1.33 kg/m 3  day COD removal. Bioelectrochemical conversion of sulphate facilitating sulphur recovery in a MFC makes it an interesting pollution abatement technique.

  20. Design of anti- and pro-aggregation variants to assess the effects of methionine oxidation in human prion protein

    PubMed Central

    Wolschner, Christina; Giese, Armin; Kretzschmar, Hans A.; Huber, Robert; Moroder, Luis; Budisa, Nediljko

    2009-01-01

    Prion disease is characterized by the α→β structural conversion of the cellular prion protein (PrPC) into the misfolded and aggregated “scrapie” (PrPSc) isoform. It has been speculated that methionine (Met) oxidation in PrPC may have a special role in this process, but has not been detailed and assigned individually to the 9 Met residues of full-length, recombinant human PrPC [rhPrPC(23-231)]. To better understand this oxidative event in PrP aggregation, the extent of periodate-induced Met oxidation was monitored by electrospray ionization-MS and correlated with aggregation propensity. Also, the Met residues were replaced with isosteric and chemically stable, nonoxidizable analogs, i.e., with the more hydrophobic norleucine (Nle) and the highly hydrophilic methoxinine (Mox). The Nle-rhPrPC variant is an α-helix rich protein (like Met-rhPrPC) resistant to oxidation that lacks the in vitro aggregation properties of the parent protein. Conversely, the Mox-rhPrPC variant is a β-sheet rich protein that features strong proaggregation behavior. In contrast to the parent Met-rhPrPC, the Nle/Mox-containing variants are not sensitive to periodate-induced in vitro aggregation. The experimental results fully support a direct correlation of the α→β secondary structure conversion in rhPrPC with the conformational preferences of Met/Nle/Mox residues. Accordingly, sporadic prion and other neurodegenerative diseases, as well as various aging processes, might also be caused by oxidative stress leading to Met oxidation. PMID:19416900

  1. Effect of solvent composition on oxide morphology during flame spray pyrolysis of metal nitrates.

    PubMed

    Strobel, Reto; Pratsinis, Sotiris E

    2011-05-28

    The effect of solvent composition on particle formation during flame spray pyrolysis of inexpensive metal-nitrates has been investigated for alumina, iron oxide, cobalt oxide, zinc oxide and magnesium oxide. The as-prepared materials were characterized by electron microscopy, nitrogen adsorption, X-ray diffraction (XRD) and disc centrifugation (XDC). The influence of solvent parameters such as boiling point, combustion enthalpy and chemical reactivity on formation of either homogeneous nanoparticles by evaporation/nucleation/coagulation (gas-to-particle conversion) or large particles through precipitation and conversion within the sprayed droplets (droplet-to-particle conversion) is discussed. For Al(2)O(3), Fe(2)O(3), Co(3)O(4) and partly also MgO, the presence of a carboxylic acid in the FSP solution resulted in homogeneous nanoparticles. This is attributed to formation of volatile metal carboxylates in solution as evidenced by attenuated total reflectance spectroscopy (ATR). For ZnO and MgO rather homogeneous nanoparticles were formed regardless of solvent composition. For ZnO this is attributed to its relatively low dissociation temperature compared to other oxides. While for MgO this is traced to the high decomposition temperature of Mg(NO(3))(2) together with Mg(OH)(2)↔MgO transformations. Cobalt oxide (Co(3)O(4)) nanoparticles made by FSP were not aggregated but rather loosely agglomerated as determined by the excellent agreement between XRD- and XDC-derived crystallite and particle sizes, respectively, pointing out the potential of FSP to make non-aggregated particles. This journal is © the Owner Societies 2011

  2. Failure Investigation of an Intra-Manifold Explosion in a Horizontally-Mounted 870 lbf Reaction Control Thruster

    NASA Technical Reports Server (NTRS)

    Durning, Joseph G., III; Westover, Shayne C.; Cone, Darren M.

    2011-01-01

    In June 2010, an 870 lbf Space Shuttle Orbiter Reaction Control System Primary Thruster experienced an unintended shutdown during a test being performed at the NASA White Sands Test Facility. Subsequent removal and inspection of the thruster revealed permanent deformation and misalignment of the thruster valve mounting plate. Destructive evaluation determined that after three nominal firing sequences, the thruster had experienced an energetic event within the fuel (monomethylhydrazine) manifold at the start of the fourth firing sequence. The current understanding of the phenomenon of intra-manifold explosions in hypergolic bipropellant thrusters is documented in literature where it is colloquially referred to as a ZOT. The typical ZOT scenario involves operation of a thruster in a gravitational field with environmental pressures above the triple point pressure of the propellants. Post-firing, when the thruster valves are commanded closed, there remains a residual quantity of propellant in both the fuel and oxidizer (nitrogen tetroxide) injector manifolds known as the "dribble volume". In an ambient ground test configuration, these propellant volumes will drain from the injector manifolds but are impeded by the local atmospheric pressure. The evacuation of propellants from the thruster injector manifolds relies on the fluids vapor pressure to expel the liquid. The higher vapor pressure oxidizer will evacuate from the manifold before the lower vapor pressure fuel. The localized cooling resulting from the oxidizer boiling during manifold draining can result in fuel vapor migration and condensation in the oxidizer passage. The liquid fuel will then react with the oxidizer that enters the manifold during the next firing and may produce a localized high pressure reaction or explosion within the confines of the oxidizer injector manifold. The typical ZOT scenario was considered during this failure investigation, but was ultimately ruled out as a cause of the explosion. Converse to the typical ZOT failure mechanism, the failure of this particular thruster was determined to be the result of liquid oxidizer being present within the fuel manifold.

  3. An investigation into support cooperativity for the deoxygenation of guaiacol over nanoparticle Ni and Rh 2P

    DOE PAGES

    Griffin, Michael B.; Baddour, Frederick G.; Habas, Susan E.; ...

    2017-06-06

    Here, the production of hydrocarbon fuels from biomass pyrolysis requires the development of effective deoxygenation catalysts, and insight into how the properties of the support influence performance is critical for catalyst design. In this report, nanoparticles of Ni and Rh 2P were synthesized using solution-phase techniques and dispersed on high surface area supports. The supports included a relatively inert material (C), an acidic reducible metal-oxide (TiO 2), an acidic irreducible metal-oxide (Al 2O 3), and a basic irreducible metal-oxide (MgO). The eight active phase/support combinations were investigated for the deoxygenation of guaiacol, a pyrolysis vapor model compound, under ex situmore » catalytic fast pyrolysis conditions (350 °C, 0.44 MPa H 2). Compared to the baseline performance of the C-supported catalysts, Ni/TiO 2 and Rh 2P/TiO 2 exhibited higher guaiacol conversion and lower O : C ratios for C 5+ products, highlighting the enhanced activity and greater selectivity to deoxygenated products derived from the use of an acidic reducible metal-oxide support. The Al 2O 3-supported catalysts also exhibited higher conversion than the C-supported catalysts and promoted alkylation reactions, which improve carbon efficiency and increase the carbon number of the C 5+ products. However, Ni/Al 2O 3 and Rh 2P/Al 2O 3 were less selective towards deoxygenated products than the C-supported catalysts. The MgO-supported catalyst exhibited lower conversion and decreased yield of deoxygenated products compared to the C-supported catalysts. The results reported here suggest that basic metal-oxide supports may inhibit deoxygenation of phenolics under CFP conditions. Contrastingly, support acidity and reducibility were demonstrated to promote conversion and selectivity to deoxygenated products, respectively.« less

  4. An environmentally compliant cerium-based conversion coating for aluminum protection

    NASA Astrophysics Data System (ADS)

    Lin, Xuan

    Chromate conversion coatings have been extensively used in the aircraft industry for the corrosion protection of aluminum alloys. Unfortunately, hexavalent chromium, which is a primary component in the chromating process, is a confirmed carcinogen. Because of rising remediation and disposal costs caused by increasingly strict regulations, the replacement of the traditional chromate conversion process is becoming a top priority in the metal finishing industry. This research focused on the electrodeposition of cerium-based coatings on 7075-T6 aluminum alloy in an electrolyte containing a cerium salt, an oxidizing agent and an organic solvent. The cerium-rich deposits were characterized by phase composition, oxidation state, coating thickness, surface morphology, deposition mechanism and polarization behavior. Chemical and electrochemical tests were utilized to compare the corrosion resistance between cerium-based coatings and chromate conversion coatings. To characterize and simulate the deposition process, a variety of approaches were utilized to study the oxidation states of cerium in various soluble and precipitated forms as a function of hydrogen peroxide and electrolyte pH. The pH ranges where the oxidation and reduction reactions dominate were determined. Further studies were performed to optimize the corrosion performance of cerium-based coatings and to understand the effects of electrolyte constituents and deposition parameters. The optimum levels for these variables were identified. A patent disclosure on the cerium-based coating process was made to the University of Missouri-Rolla and has now been officially filed with the U.S. Patent Office.

  5. Oxygen vacancy formation characteristics in the bulk and across different surface terminations of La (1₋x)Sr xFe (1₋y)Co yO (3₋δ) perovskite oxides for CO 2 conversion

    DOE PAGES

    Maiti, Debtanu; Daza, Yolanda A.; Yung, Matthew M.; ...

    2016-03-07

    Density functional theory (DFT) based investigation of two parameters of prime interest -- oxygen vacancy and surface terminations along (100) and (110) planes -- has been conducted for La (1-x)Sr xFe(1-y)Co yO (3-more » $$\\delta$$) perovskite oxides in view of their application towards thermochemical carbon dioxide conversion reactions. The bulk oxygen vacancy formation energies for these mixed perovskite oxides are found to increase with increasing lanthanum and iron contents in the 'A' site and 'B' site, respectively. Surface terminations along (100) and (110) crystal planes are studied to probe their stability and their capabilities to accommodate surface oxygen vacancies. Amongst the various terminations, the oxygen-rich (110) surface and strontium-rich (100) surface are the most stable, while transition metal-rich terminations along (100) revealed preference towards the production of oxygen vacancies. The carbon dioxide adsorption strength, a key descriptor for CO 2 conversion reactions, is found to increase on oxygen vacant surfaces thus establishing the importance of oxygen vacancies in CO 2 conversion reactions. Amongst all the surface terminations, the lanthanum-oxygen terminated surface exhibited the strongest CO 2 adsorption strength. Finally, the theoretical prediction of the oxygen vacancy trends and the stability of the samples were corroborated by the temperature-programmed reduction and oxidation reactions and in situ XRD crystallography.« less

  6. Conversion of Methane into Methanol and Ethanol over Nickel Oxide on Ceria-Zirconia Catalysts in a Single Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Okolie, Chukwuemeka; Belhseine, Yasmeen F.; Lyu, Yimeng

    Direct conversion of methane into alcohols is a promising technology for converting stranded methane reserves into liquids that can be transported in pipelines and upgraded to value-added chemicals. We demonstrate that a catalyst consisting of small nickel oxide clusters supported on ceria-zirconia (NiO/CZ) can selectively oxidize methane to methanol and ethanol in a single, steady-state process at 723 K using O2 as an abundantly available oxidant. The presence of steam is required to obtain alcohols rather than CO2 as the product of catalytic combustion. The unusual activity of this catalyst is attributed to the synergy between the small Lewis acidicmore » NiO clusters and the redox-active CZ support, which also stabilizes the small NiO clusters.« less

  7. Activity of Cu-activated carbon fiber catalyst in wet oxidation of ammonia solution.

    PubMed

    Hung, Chang-Mao

    2009-07-30

    Aqueous solutions of 200-1000 mg/L of ammonia were oxidized in a trickle-bed reactor using Cu-activated carbon fiber (ACF) catalysts, which were prepared by incipient wet impregnation with aqueous solutions of copper nitrate that was deposited on ACF substrates. The results reveal that the conversion of ammonia by wet oxidation in the presence of Cu-ACF catalysts was a function of the metal loading weight ratio of the catalyst. The total conversion efficiency of ammonia was 95% during wet oxidation over the catalyst at 463 K at an oxygen partial pressure of 3.0 MPa. Moreover, the effect of the initial concentration of ammonia and the reaction temperature on the removal of ammonia from the effluent streams was also studied at a liquid space velocity of less than 3.0 h(-1).

  8. Environmental monitoring handbook for coal conversion facilities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salk, M.S.; DeCicco, S.G.

    1978-05-01

    The primary objectives of the Department of Energy's (DOE) coal conversion program are to demonstrate the environmental acceptability, technical feasibility, and economic viability of various technologies for gaseous, liquid, and solid fuels from coal. The Environmental Monitoring Handbook for Coal Conversion Facilities will help accomplish the objective of environmental acceptability by guiding the planning and execution of socioeconomic and environmental monitoring programs for demonstration facilities. These programs will provide information adequate to (1) predict, insofar as is possible, the potential impacts of construction and operation of a coal conversion plant, (2) verify the occurrence of these or any other impactsmore » during construction and operation, (3) determine the adequacy of mitigating measures to protect the environment, (4) develop effluent source terms for process discharges, and (5) determine the effectiveness of pollution control equipment. Although useful in a variety of areas, the handbook is intended primarily for contractors who, as industrial partners with DOE, are building coal conversion plants. For the contractor it is a practical guide on (1) the methodology for developing site- and process-specific environmental monitoring programs, (2) state-of-the-art sampling and analytical techniques, and (3) impact analyses.To correspond to the phases of project activity, the subject matter is divided into four stages of monitoring: (1) a reconnaissance or synoptic survey, (2) preconstruction or baseline, (3) construction, and (4) operation, including process monitoring (prepared by Radian Corp., McLean, Va.). For each stage of monitoring, guidelines are given on socioeconomics, aquatic and terrestrial ecology, air quality and meteorology, surface and groundwater quality, geohydrology and soil survey, and surface water hydrology.« less

  9. The Oxidation of Secondary Alcohols with Cr (VI).

    ERIC Educational Resources Information Center

    Mason, Timothy J.

    1982-01-01

    Describes experiments in which acid chromate oxidation rates of four secondary alcohols are determined and related to the differences in strain relief involved in the conversion of the alcohols to their respective ketone products. All four oxidations can be completed in a 4-hour laboratory period. (Author/JN)

  10. Formate-Dependent Microbial Conversion of CO2 and the Dominant Pathways of Methanogenesis in Production Water of High-temperature Oil Reservoirs Amended with Bicarbonate.

    PubMed

    Yang, Guang-Chao; Zhou, Lei; Mbadinga, Serge M; Liu, Jin-Feng; Yang, Shi-Zhong; Gu, Ji-Dong; Mu, Bo-Zhong

    2016-01-01

    CO2 sequestration in deep-subsurface formations including oil reservoirs is a potential measure to reduce the CO2 concentration in the atmosphere. However, the fate of the CO2 and the ecological influences in carbon dioxide capture and storage (CDCS) facilities is not understood clearly. In the current study, the fate of CO2 (in bicarbonate form; 0∼90 mM) with 10 mM of formate as electron donor and carbon source was investigated with high-temperature production water from oilfield in China. The isotope data showed that bicarbonate could be reduced to methane by methanogens and major pathway of methanogenesis could be syntrophic formate oxidation coupled with CO2 reduction and formate methanogenesis under the anaerobic conditions. The bicarbonate addition induced the shift of microbial community. Addition of bicarbonate and formate was associated with a decrease of Methanosarcinales, but promotion of Methanobacteriales in all treatments. Thermodesulfovibrio was the major group in all the samples and Thermacetogenium dominated in the high bicarbonate treatments. The results indicated that CO2 from CDCS could be transformed to methane and the possibility of microbial CO2 conversion for enhanced microbial energy recovery in oil reservoirs.

  11. Formate-Dependent Microbial Conversion of CO2 and the Dominant Pathways of Methanogenesis in Production Water of High-temperature Oil Reservoirs Amended with Bicarbonate

    PubMed Central

    Yang, Guang-Chao; Zhou, Lei; Mbadinga, Serge M.; Liu, Jin-Feng; Yang, Shi-Zhong; Gu, Ji-Dong; Mu, Bo-Zhong

    2016-01-01

    CO2 sequestration in deep-subsurface formations including oil reservoirs is a potential measure to reduce the CO2 concentration in the atmosphere. However, the fate of the CO2 and the ecological influences in carbon dioxide capture and storage (CDCS) facilities is not understood clearly. In the current study, the fate of CO2 (in bicarbonate form; 0∼90 mM) with 10 mM of formate as electron donor and carbon source was investigated with high-temperature production water from oilfield in China. The isotope data showed that bicarbonate could be reduced to methane by methanogens and major pathway of methanogenesis could be syntrophic formate oxidation coupled with CO2 reduction and formate methanogenesis under the anaerobic conditions. The bicarbonate addition induced the shift of microbial community. Addition of bicarbonate and formate was associated with a decrease of Methanosarcinales, but promotion of Methanobacteriales in all treatments. Thermodesulfovibrio was the major group in all the samples and Thermacetogenium dominated in the high bicarbonate treatments. The results indicated that CO2 from CDCS could be transformed to methane and the possibility of microbial CO2 conversion for enhanced microbial energy recovery in oil reservoirs. PMID:27047478

  12. Heterometallic metal-organic framework-templated synthesis of porous Co3O4/ZnO nanocage catalysts for the carbonylation of glycerol

    NASA Astrophysics Data System (ADS)

    Lü, Yinyun; Jiang, Yating; Zhou, Qi; Li, Yunmei; Chen, Luning; Kuang, Qin; Xie, Zhaoxiong; Zheng, Lansun

    2017-12-01

    The efficient synthesis of glycerol carbonate (GLC) has recently received great attention due to its significance in reducing excess glycerol in biodiesel production as well as its promising applications in several industrial fields. However, the achievement of high conversion and high selectivity of GLC from glycerol in heterogeneous catalytic processes remains a challenge due to the absence of high-performance solid catalysts. Herein, highly porous nanocage catalysts composed of well-mixed Co3O4 and ZnO nanocrystals were successfully fabricated via a facile heterometallic metal-organic framework (MOF)-templated synthetic route. Benefiting from a high porosity and the synergistic effect between Co3O4 and ZnO, the as-prepared composite catalysts exhibited a significantly enhanced production efficiency of GLC in the carbonylation reaction of glycerol with urea compared to the single-component counterparts. The yield of GLC over the Co50Zn50-350 catalyst reached 85.2%, with 93.3% conversion and near 91% GLC selectivity, and this catalytic performance was superior to that over most heterogeneous catalysts. More importantly, the proposed templated synthetic strategy of heterometallic MOFs facilitates the regulation of catalyst composition and surface structure and can therefore be potentially extended in the tailoring of other metal oxide composite catalysts.

  13. CFD analysis of municipal solid waste combustion using detailed chemical kinetic modelling.

    PubMed

    Frank, Alex; Castaldi, Marco J

    2014-08-01

    Nitrogen oxides (NO x ) emissions from the combustion of municipal solid waste (MSW) in waste-to-energy (WtE) facilities are receiving renewed attention to reduce their output further. While NO x emissions are currently 60% below allowed limits, further reductions will decrease the air pollution control (APC) system burden and reduce consumption of NH3. This work combines the incorporation of the GRI 3.0 mechanism as a detailed chemical kinetic model (DCKM) into a custom three-dimensional (3D) computational fluid dynamics (CFD) model fully to understand the NO x chemistry in the above-bed burnout zones. Specifically, thermal, prompt and fuel NO formation mechanisms were evaluated for the system and a parametric study was utilized to determine the effect of varying fuel nitrogen conversion intermediates between HCN, NH3 and NO directly. Simulation results indicate that the fuel nitrogen mechanism accounts for 92% of the total NO produced in the system with thermal and prompt mechanisms accounting for the remaining 8%. Results also show a 5% variation in final NO concentration between HCN and NH3 inlet conditions, demonstrating that the fuel nitrogen intermediate assumed is not significant. Furthermore, the conversion ratio of fuel nitrogen to NO was 0.33, revealing that the majority of fuel nitrogen forms N2. © The Author(s) 2014.

  14. Alcohol conversion

    DOEpatents

    Wachs, Israel E.; Cai, Yeping

    2002-01-01

    Preparing an aldehyde from an alcohol by contacting the alcohol in the presence of oxygen with a catalyst prepared by contacting an intimate mixture containing metal oxide support particles and particles of a catalytically active metal oxide from Groups VA, VIA, or VIIA, with a gaseous stream containing an alcohol to cause metal oxide from the discrete catalytically active metal oxide particles to migrate to the metal oxide support particles and to form a monolayer of catalytically active metal oxide on said metal oxide support particles.

  15. Atomic Oxygen Durability Evaluation of a UV Curable Ceramer Protective Coating

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; Karniotis, Christina A.; Dworak, David; Soucek, Mark

    2004-01-01

    The exposure of most silicones to atomic oxygen in low Earth orbit (LEO) results in the oxidative loss of methyl groups with a gradual conversion to oxides of silicon. Typically there is surface shrinkage of oxidized silicone protective coatings which leads to cracking of the partially oxidized brittle surface. Such cracks widen and branch crack with continued atomic oxygen exposure ultimately allowing atomic oxygen to reach any hydrocarbon polymers under the silicone coating. A need exists for a paintable silicone coating that is free from such surface cracking and can be effectively used for protection of polymers and composites in LEO. A new type of silicone based protective coating holding such potential was evaluated for atomic oxygen durability in an RF atomic oxygen plasma exposure facility. The coating consisted of a UV curable inorganic/organic hybrid coating, known as a ceramer, which was fabricated using a methyl substituted polysiloxane binder and nanophase silicon-oxo-clusters derived from sol-gel precursors. The polysiloxane was functionalized with a cycloaliphatic epoxide in order to be cured at ambient temperature via a cationic UV induced curing mechanism. Alkoxy silane groups were also grafted onto the polysiloxane chain, through hydrosilation, in order to form a network with the incorporated silicon-oxo-clusters. The prepared polymer was characterized by H-1 and Si-29 NMR, FT-IR, and electrospray ionization mass spectroscopy. The paper will present the results of atomic oxygen protection ability of thin ceramer coatings on Kapton H as evaluated over a range of atomic oxygen fluence levels.

  16. Facile Preparation of Highly Conductive Metal Oxides by Self-Combustion for Solution-Processed Thermoelectric Generators.

    PubMed

    Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

    2016-03-02

    Highly conductive indium zinc oxide (IZO) thin films were successfully fabricated via a self-combustion reaction for application in solution-processed thermoelectric devices. Self-combustion efficiently facilitates the conversion of soluble precursors into metal oxides by lowering the required annealing temperature of oxide films, which leads to considerable enhancement of the electrical conductivity of IZO thin films. Such enhanced electrical conductivity induced by exothermic heat from a combustion reaction consequently yields high performance IZO thermoelectric films. In addition, the effect of the composition ratio of In to Zn precursors on the electrical and thermoelectric properties of the IZO thin films was investigated. IZO thin films with a composition ratio of In:Zn = 6:2 at the low annealing temperature of 350 °C showed an enhanced electrical conductivity, Seebeck coefficient, and power factor of 327 S cm(-1), 50.6 μV K(-1), and 83.8 μW m(-1) K(-2), respectively. Moreover, the IZO thin film prepared at an even lower temperature of 300 °C retained a large power factor of 78.7 μW m(-1) K(-2) with an electrical conductivity of 168 S cm(-1). Using the combustive IZO precursor, a thermoelectric generator consisting of 15 legs was fabricated by a printing process. The thermoelectric array generated a thermoelectric voltage of 4.95 mV at a low temperature difference (5 °C). We suggest that the highly conductive IZO thin films by self-combustion may be utilized for fabricating n-type flexible printed thermoelectric devices.

  17. Oxidative desulfurization of benzene fraction on transition metal oxides

    NASA Astrophysics Data System (ADS)

    Boikov, E. B.; Vishnetskaya, M. V.

    2013-02-01

    It is established that molecular oxygen is able to oxidize thiophene selectively in a mixture with benzene on V2O5 · MoO3. The introduction of thiophene inhibits the oxidation of benzene. It is shown that the conversion of thiophene during operation of the catalyst is reduced at first and then increases until it reaches its initial value.

  18. Guidelines for the conversion of urban four-lane undivided roadways to three-lane two-way left-turn lane facilities

    DOT National Transportation Integrated Search

    2001-04-01

    The primary objective of this research project was to develop a set of guidelines to assist in the selection of candidate roadways for urban four-lane undivided to three-lane cross section conversions. The authors evaluated and assessed the physical,...

  19. Oral Conversations Online: Redefining Oral Competence in Synchronous Environments

    ERIC Educational Resources Information Center

    Lamy, Marie-Noelle

    2004-01-01

    In this article the focus is on methodology for analysing learner-learner oral conversations mediated by computers. With the increasing availability of synchronous voice-based groupware and the additional facilities offered by audio-graphic tools, language learners have opportunities for collaborating on oral tasks, supported by visual and textual…

  20. The Formation of Ethane from Carbon Dioxide under Cold Plasma

    NASA Astrophysics Data System (ADS)

    Zhang, Xiu-ling; Zhang, Lin; Dai, Bin; Gong, Wei-min; Liu, Chang-hou

    2001-04-01

    Pulsed-corona plasma has been used as a new method for ethane dehydrogenation at low temperature and normal pressure using carbon dioxide as an oxidant in this paper. The effect of carbon dioxide content in the feed, power input, and flow rate of the reactants on the ethane dehydrogenation has been investigated. The experimental results show that the conversion of ethane increases with the increase in the amount of carbon dioxide in the feed. The yield of ethylene and acetylene decreases with the increase in the yield of carbon monoxide, indicating that the increased carbon dioxide leads to the part of ethylene and acetylene being oxidized to carbon monoxide. Power input is primarily an electrical parameter in pulsed-corona plasma, which plays an important role in reactant conversion and product formation. When the power input reaches 16 W, ethane conversion is 41.0% and carbon dioxide conversion is 26.3%. The total yield of ethylene and acetylene is 15.6%. The reduced flow rate of feed improves the conversion of ethane, carbon dioxide and the yield of acetylene, and induces carbon deposit as well.

  1. Thermocatalytic Destruction of Gas-Phase Perchloroethylene Using Propane as a Hydrogen Source

    PubMed Central

    Willinger, Marty; Rupp, Erik; Barbaris, Brian; Gao, Song; Arnolda, Robert; Betterton, Eric; Sáez, A. Eduardo

    2009-01-01

    The use of propane in combination with oxygen to promote the destruction of perchloroethylene (PCE) over a platinum (Pt)/rhodium (Rh) catalyst on a cerium/zirconium oxide washcoat supported on an alumina monolith was explored. Conversions of PCE were measured in a continuous flow reactor with residence times less than 0.5 s and temperatures ranging from 200 to 600°C. The presence of propane was shown to increase significantly the conversion of PCE over oxygen-only conditions. Conversions close to 100% were observed at temperatures lower than 450°C with 20% oxygen and 2% propane in the feed, which makes this process attractive from a practical standpoint. In the absence of oxygen, PCE conversion is even higher, but the catalyst suffers significant deactivation in less than an hour. Even though results show that oxygen competes with reactants for active sites on the catalyst, the long-term stability that oxygen confers to the catalyst makes the process an efficient alternative to PCE oxidation. A Langmuir-Hinshelwood competitive adsorption model is proposed to quantify PCE conversion. PMID:19217713

  2. Kinetics and mechanism of the oxidation of S(IV) by ozone in aqueous solution with particular reference to SO2 conversion in nonurban tropospheric clouds

    NASA Technical Reports Server (NTRS)

    Maahs, H. G.

    1983-01-01

    Results are presented from a laboratory study of the kinetics of the S(IV)-O3 reaction in aqueous solution, including measurements of the effects of UV radiation, dissolved transition metals, and an antioxidant (hydroquinone) on the rate. On the basis of the results, relative rates of S(IV) conversion by O3 in tropospheric cloud water are compared with those predicted for H2O2 and for O2. The reaction mechanism is discussed, with an outline given of the elements of a possible reaction scheme. Application of the rate constants obtained to SO2 conversion in cloud water predicts conversion rates by ozone to be competitive with those by H2O2 at pH above about 4.5 and to dominate at pH above about 5.5. It is pointed out that since these pH's are typical for nonurban tropospheric cloud water, ozone is a potentially important contributor to the overall oxidative conversion of SO2 to sulfate in the nonurban troposphere.

  3. Exercise performed immediately after fructose ingestion enhances fructose oxidation and suppresses fructose storage.

    PubMed

    Egli, Léonie; Lecoultre, Virgile; Cros, Jérémy; Rosset, Robin; Marques, Anne-Sophie; Schneiter, Philippe; Hodson, Leanne; Gabert, Laure; Laville, Martine; Tappy, Luc

    2016-02-01

    Exercise prevents the adverse effects of a high-fructose diet through mechanisms that remain unknown. We assessed the hypothesis that exercise prevents fructose-induced increases in very-low-density lipoprotein (VLDL) triglycerides by decreasing the fructose conversion into glucose and VLDL-triglyceride and fructose carbon storage into hepatic glycogen and lipids. Eight healthy men were studied on 3 occasions after 4 d consuming a weight-maintenance, high-fructose diet. On the fifth day, the men ingested an oral (13)C-labeled fructose load (0.75 g/kg), and their total fructose oxidation ((13)CO2 production), fructose storage (fructose ingestion minus (13)C-fructose oxidation), fructose conversion into blood (13)C glucose (gluconeogenesis from fructose), blood VLDL-(13)C palmitate (a marker of hepatic de novo lipogenesis), and lactate concentrations were monitored over 7 postprandial h. On one occasion, participants remained lying down throughout the experiment [fructose treatment alone with no exercise condition (NoEx)], and on the other 2 occasions, they performed a 60-min exercise either 75 min before fructose ingestion [exercise, then fructose condition (ExFru)] or 90 min after fructose ingestion [fructose, then exercise condition (FruEx)]. Fructose oxidation was significantly (P < 0.001) higher in the FruEx (80% ± 3% of ingested fructose) than in the ExFru (46% ± 1%) and NoEx (49% ± 1%). Consequently, fructose storage was lower in the FruEx than in the other 2 conditions (P < 0.001). Fructose conversion into blood (13)C glucose, VLDL-(13)C palmitate, and postprandial plasma lactate concentrations was not significantly different between conditions. Compared with sedentary conditions, exercise performed immediately after fructose ingestion increases fructose oxidation and decreases fructose storage. In contrast, exercise performed before fructose ingestion does not significantly alter fructose oxidation and storage. In both conditions, exercise did not abolish fructose conversion into glucose or its incorporation into VLDL triglycerides. This trial was registered at clinicaltrials.gov as NCT01866215. © 2016 American Society for Nutrition.

  4. Methodology for worker neutron exposure evaluation in the PDCF facility design.

    PubMed

    Scherpelz, R I; Traub, R J; Pryor, K H

    2004-01-01

    A project headed by Washington Group International is meant to design the Pit Disassembly and Conversion Facility (PDCF) to convert the plutonium pits from excessed nuclear weapons into plutonium oxide for ultimate disposition. Battelle staff are performing the shielding calculations that will determine appropriate shielding so that the facility workers will not exceed target exposure levels. The target exposure levels for workers in the facility are 5 mSv y(-1) for the whole body and 100 mSv y(-1) for the extremity, which presents a significant challenge to the designers of a facility that will process tons of radioactive material. The design effort depended on shielding calculations to determine appropriate thickness and composition for glove box walls, and concrete wall thicknesses for storage vaults. Pacific Northwest National Laboratory (PNNL) staff used ORIGEN-S and SOURCES to generate gamma and neutron source terms, and Monte Carlo (computer code for) neutron photon (transport) (MCNP-4C) to calculate the radiation transport in the facility. The shielding calculations were performed by a team of four scientists, so it was necessary to develop a consistent methodology. There was also a requirement for the study to be cost-effective, so efficient methods of evaluation were required. The calculations were subject to rigorous scrutiny by internal and external reviewers, so acceptability was a major feature of the methodology. Some of the issues addressed in the development of the methodology included selecting appropriate dose factors, developing a method for handling extremity doses, adopting an efficient method for evaluating effective dose equivalent in a non-uniform radiation field, modelling the reinforcing steel in concrete, and modularising the geometry descriptions for efficiency. The relative importance of the neutron dose equivalent compared with the gamma dose equivalent varied substantially depending on the specific shielding conditions and lessons were learned from this effect. This paper addresses these issues and the resulting methodology.

  5. Conversion of Indigenous Agricultural Waste Feedstocks to Fuel Ethanol. Cooperative Research and Development Final Report, CRADA Number CRD-13-504

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elander, Richard

    This Cooperative Research and Development Agreement (CRADA) is between the National Renewable Energy Laboratory (NREL), a world leader in biomass conversion research and Ecopetrol American Inc., Ecopetrol S.A.'s U.S. subsidiary. The research and development efforts described in the Joint Work Statement (JWS) will take advantage of the strengths of both parties. NREL will use its Integrated Biorefinery Facility and vast experience in the conversion of lignocellulosic feedstocks to fuel ethanol to develop processes for the conversion of Ecopetrol's feedstocks. Ecopetrol will establish the infrastructure in Columbia to commercialize the conversion process.

  6. A facile one-step route to synthesize cage-like silica hollow spheres loaded with superparamagnetic iron oxide nanoparticles in their shells.

    PubMed

    Li, Ling; Choo, Eugene Shi Guang; Tang, Xiaosheng; Ding, Jun; Xue, Junmin

    2009-02-28

    Cage-like silica hollow spheres loaded with superparamagnetic iron oxide nanoparticles incorporated in their macroporous shells are synthesized in a facile manner through a one-step oil-in-diethylene glycol (DEG) microemulsion route.

  7. Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O 2 mixed oxide pellets

    NASA Astrophysics Data System (ADS)

    Khot, P. M.; Nehete, Y. G.; Fulzele, A. K.; Baghra, Chetan; Mishra, A. K.; Afzal, Mohd.; Panakkal, J. P.; Kamath, H. S.

    2012-01-01

    Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th, 233U)O 2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO 2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O 2 pellets. In this study, fabrication of (Th,U)O 2 mixed oxide pellets containing 3-5 wt.% UO 2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.

  8. Impact of conversion to mixed-oxide fuels on reactor structural components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yahr, G.T.

    1997-04-01

    The use of mixed-oxide (MOX) fuel to replace conventional uranium fuel in commercial light-water power reactors will result in an increase in the neutron flux. The impact of the higher flux on the structural integrity of reactor structural components must be evaluated. This report briefly reviews the effects of radiation on the mechanical properties of metals. Aging degradation studies and reactor operating experience provide a basis for determining the areas where conversion to MOX fuels has the potential to impact the structural integrity of reactor components.

  9. Dimensionally Controlled Lithiation of Chromium Oxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fister, Tim T.; Hu, Xianyi; Esbenshade, Jennifer

    Oxide conversion reactions are an alternative approach for high capacity lithium ion batteries but are known to suffer from structural irreversibility associated with the phase separation and reconstitution of reduced metal species and Li2O. In particular, the morphology of the reduced metal species is thought to play a critical role in the electrochemical properties of a conversion material. Here we use a model electrode with alternating layers of chromium and chromium oxide to better understand and control these phase changes in real-time and at molecular length scales. Despite lacking crystallinity at the atomic scale, this superstructure is observed (with X-raymore » reflectivity, XR) to lithiate and delithiate in a purely one-dimensional manner, preserving the layered structure. The XR data show that the metal layers act as nucleation sites for the reduction of chromium in the conversion reaction. Irreversibility during delithiation is due to the formation of a ternary phase, LiCrO2, which can be further delithiated at higher potentials. The results reveal that the combination of confining lithiation to nanoscale sheets of Li2O and the availability of reaction sites in the metal layers in the layered structure is a strategy for improving the reversibility and mass transport properties that can be used in a wide range of conversion materials.« less

  10. 40 CFR 60.73 - Emission monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the applicable standard (kg/metric ton, lb/ton). The conversion factor shall be established by...., kg/metric ton per ppm (lb/ton per ppm). The conversion factor shall be reestablished during any... continuous monitoring system for measuring nitrogen oxides (NOX). The pollutant gas mixtures under...

  11. 40 CFR 60.73 - Emission monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the applicable standard (kg/metric ton, lb/ton). The conversion factor shall be established by...., kg/metric ton per ppm (lb/ton per ppm). The conversion factor shall be reestablished during any... continuous monitoring system for measuring nitrogen oxides (NOX). The pollutant gas mixtures under...

  12. 40 CFR 60.73 - Emission monitoring.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the applicable standard (kg/metric ton, lb/ton). The conversion factor shall be established by...., kg/metric ton per ppm (lb/ton per ppm). The conversion factor shall be reestablished during any... continuous monitoring system for measuring nitrogen oxides (NOX). The pollutant gas mixtures under...

  13. 40 CFR 60.73 - Emission monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the applicable standard (kg/metric ton, lb/ton). The conversion factor shall be established by...., kg/metric ton per ppm (lb/ton per ppm). The conversion factor shall be reestablished during any... continuous monitoring system for measuring nitrogen oxides (NOX). The pollutant gas mixtures under...

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kattel, Shyam; Liu, Ping; Chen, Jingguang G.

    The chemical transformation of CO 2 not only mitigates the anthropogenic CO 2 emission into the Earth’s atmosphere but also produces carbon compounds that can be used as precursors for the production of chemicals and fuels. The activation and conversion of CO 2 can be achieved on multifunctional catalytic sites available at the metal/oxide interface by taking advantage of the synergy between the metal nanoparticles and oxide support. In this paper, we look at the recent progress in mechanistic studies of CO 2 hydrogenation to C1 (CO, CH 3OH, and CH 4) compounds on metal/oxide catalysts. On this basis, wemore » are able to provide a better understanding of the complex reaction network, grasp the capability of manipulating structure and combination of metal and oxide at the interface in tuning selectivity, and identify the key descriptors to control the activity and, in particular, the selectivity of catalysts. In conclusion, we also discuss challenges and future research opportunities for tuning the selective conversion of CO 2 on metal/oxide catalysts.« less

  15. 4. Historic photo of fuel and oxidant tanks in hilltop ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic photo of fuel and oxidant tanks in hilltop area of rocket engine test facility. 1956. On file at NASA Plumbrook Research Center, Sandusky, Ohio. NASA GRC photo number C-1956-160D. - Rocket Engine Testing Facility, NASA Glenn Research Center, Cleveland, Cuyahoga County, OH

  16. Heavy Gas Conversion of the NASA Langley Transonic Dynamics Tunnel

    NASA Technical Reports Server (NTRS)

    Corliss, James M.; Cole, Stanley, R.

    1998-01-01

    The heavy gas test medium has recently been changed in the Transonic Dynamics Tunnel (TDT) at the NASA Langley Research Center. A NASA Construction of Facilities project has converted the TDT heavy gas from dichlorodifluoromethane (R12) to 1,1,1,2 tetrafluoroethane (R134a). The facility s heavy gas processing system was extensively modified to implement the conversion to R134a. Additional system modifications have improved operator interfaces, hardware reliability, and quality of the research data. The facility modifications included improvements to the heavy gas compressor and piping, the cryogenic heavy gas reclamation system, and the heavy gas control room. A series of wind tunnel characterization and calibration tests are underway. Results of the flow characterization tests show the TDT operating envelope in R134a to be very similar to the previous operating envelope in R12.

  17. Catalyst for the methanation of carbon monoxide in sour gas

    DOEpatents

    Kustes, William A.; Hausberger, Arthur L.

    1985-01-01

    The invention involves the synergistic effect of the specific catalytic constituents on a specific series of carriers for the methanation of carbon monoxide in the presence of sulfur at relatively high temperatures and at low steam to gas ratios in the range of 0.2:1 or less. This effect was obtained with catalysts comprising the mixed sulfides and oxides of nickel and chromium supported on carriers comprising magnesium aluminate and magnesium silicate. Conversion of carbon monoxide to methane was in the range of from 40 to 80%. Tests of this combination of metal oxides and sulfides on other carriers and tests of other metal oxides and sulfides on the same carrier produced a much lower level of conversion.

  18. Microbial conversion of ethylbenzene to 1-phenethanol and acetophenone by Nocardia tartaricans ATCC 31190.

    PubMed Central

    Cox, D P; Goldsmith, C D

    1979-01-01

    A culture of Nocardia tartaricans ATCC 31190 was capable of catalyzing the conversion of ethylbenzene to 1-phenethanol and acetophenone while growing in a shake flask culture with hexadecane as the source of carbon and energy. This subterminal oxidative reaction with ethylbenzene appears not to have been previously reported for Nocardia species. When N. tartaricans was grown on glucose as its source of carbon and energy and ethylbenzene was added, no subsequent production of 1-phenethanol or acetophenone was observed. The mechanisms of 1-phenethanol and acetophenone production from ethylbenzene are thought to involve a subterminal oxidation of the alpha-carbon of the alkyl group to 1-phenethanol followed by biological oxidation of the latter to acetophenone. PMID:93878

  19. Microbial conversion of ethylbenzene to 1-phenethanol and acetophenone by Nocardia tartaricans ATCC 31190.

    PubMed

    Cox, D P; Goldsmith, C D

    1979-09-01

    A culture of Nocardia tartaricans ATCC 31190 was capable of catalyzing the conversion of ethylbenzene to 1-phenethanol and acetophenone while growing in a shake flask culture with hexadecane as the source of carbon and energy. This subterminal oxidative reaction with ethylbenzene appears not to have been previously reported for Nocardia species. When N. tartaricans was grown on glucose as its source of carbon and energy and ethylbenzene was added, no subsequent production of 1-phenethanol or acetophenone was observed. The mechanisms of 1-phenethanol and acetophenone production from ethylbenzene are thought to involve a subterminal oxidation of the alpha-carbon of the alkyl group to 1-phenethanol followed by biological oxidation of the latter to acetophenone.

  20. Maximizing omnidirectional light harvesting in metal oxide hyperbranched array architectures

    NASA Astrophysics Data System (ADS)

    Wu, Wu-Qiang; Feng, Hao-Lin; Rao, Hua-Shang; Xu, Yang-Fan; Kuang, Dai-Bin; Su, Cheng-Yong

    2014-05-01

    The scrupulous design of nanoarchitectures and smart hybridization of specific active materials are closely related to the overall photovoltaic performance of an anode electrode. Here we present a solution-based strategy for the fabrication of well-aligned metal oxide-based nanowire-nanosheet-nanorod hyperbranched arrays on transparent conducting oxide substrates. For these hyperbranched arrays, we observe a twofold increment in dye adsorption and enhanced light trapping and scattering capability compared with the pristine titanium dioxide nanowires, and thus a power conversion efficiency of 9.09% is achieved. Our growth approach presents a strategy to broaden the photoresponse and maximize the light-harvesting efficiency of arrays architectures, and may lead to applications for energy conversion and storage, catalysis, water splitting and gas sensing.

  1. Maximizing omnidirectional light harvesting in metal oxide hyperbranched array architectures.

    PubMed

    Wu, Wu-Qiang; Feng, Hao-Lin; Rao, Hua-Shang; Xu, Yang-Fan; Kuang, Dai-Bin; Su, Cheng-Yong

    2014-05-29

    The scrupulous design of nanoarchitectures and smart hybridization of specific active materials are closely related to the overall photovoltaic performance of an anode electrode. Here we present a solution-based strategy for the fabrication of well-aligned metal oxide-based nanowire-nanosheet-nanorod hyperbranched arrays on transparent conducting oxide substrates. For these hyperbranched arrays, we observe a twofold increment in dye adsorption and enhanced light trapping and scattering capability compared with the pristine titanium dioxide nanowires, and thus a power conversion efficiency of 9.09% is achieved. Our growth approach presents a strategy to broaden the photoresponse and maximize the light-harvesting efficiency of arrays architectures, and may lead to applications for energy conversion and storage, catalysis, water splitting and gas sensing.

  2. Oxidation of 1,3,7-trimethylxanthine by hypochlorite ion

    NASA Astrophysics Data System (ADS)

    Kheidorov, V. P.; Ershov, Yu. A.; Chalyi, G. Yu.; Titorovich, O. V.

    2011-08-01

    The kinetics of the oxidative conversion of 1,3,7-trimethylxanthine upon treatment with hypochlorite ions (OCl-) in aqueous medium at 283-298 K and pH 8.2 was studied. The reaction order with respect to each component was determined and proved to be 1. It was established that the temperature dependence of the reaction rate follows the Arrhenius equation. The activation parameters of the reaction were measured: E a = 33.58 kJ/mol, Δ H ≠ = 31.12 kJ/mol, Δ S ≠ = -170.02 J/(K mol), Δ G ≠ = 81.45 kJ/mol. The stoichiometry of the reaction was studied, and the chemistry of the oxidative conversion of caffeine treated with OCl- is discussed.

  3. Tuning Selectivity of CO 2 Hydrogenation Reactions at the Metal/Oxide Interface

    DOE PAGES

    Kattel, Shyam; Liu, Ping; Chen, Jingguang G.

    2017-06-26

    The chemical transformation of CO 2 not only mitigates the anthropogenic CO 2 emission into the Earth’s atmosphere but also produces carbon compounds that can be used as precursors for the production of chemicals and fuels. The activation and conversion of CO 2 can be achieved on multifunctional catalytic sites available at the metal/oxide interface by taking advantage of the synergy between the metal nanoparticles and oxide support. In this paper, we look at the recent progress in mechanistic studies of CO 2 hydrogenation to C1 (CO, CH 3OH, and CH 4) compounds on metal/oxide catalysts. On this basis, wemore » are able to provide a better understanding of the complex reaction network, grasp the capability of manipulating structure and combination of metal and oxide at the interface in tuning selectivity, and identify the key descriptors to control the activity and, in particular, the selectivity of catalysts. In conclusion, we also discuss challenges and future research opportunities for tuning the selective conversion of CO 2 on metal/oxide catalysts.« less

  4. Oxidative degradation of phenols in sono-Fenton-like systems upon high-frequency ultrasound irradiation

    NASA Astrophysics Data System (ADS)

    Aseev, D. G.; Sizykh, M. R.; Batoeva, A. A.

    2017-12-01

    The kinetics of oxidative degradation of phenol and chlorophenols upon acoustic cavitation in the megahertz range (1.7 MHz) is studied experimentally in model systems, and the involvement of in situ generated reactive oxygen species (ROSs) is demonstrated. The phenols subjected to high frequency ultrasound (HFUS) are ranked in terms of their rate of conversion: 2,4,6-trichlorophenol > 2,4-dichlorophenol 2-chlorophenol > 4-chlorophenol phenol. Oxidative degradation upon HFUS irradiation is most efficient at low concentrations of pollutants, due to the low steady-state concentrations of the in situ generated ROSs. A dramatic increase is observed in the efficiency of oxidation in several sonochemical oxidative systems (HFUS in combination with other chemical oxidative factors). The system with added Fe2+ (a sono-Fenton system) derives its efficiency from hydrogen peroxide generated in situ as a result of the recombination of OH radicals. The S2O8 2-/Fe2+/HFUS system has a synergetic effect on substrate oxidation that is attributed to a radical chain mechanism. In terms of the oxidation rates, degrees of conversion, and specific energy efficiencies of 4-chlorophenol oxidation based on the amount of oxidized substance per unit of expended energy the considered sonochemical oxidative systems form the series HFUS < S2O8 2-/HFUS < S2O8 2-/Fe2+/HFUS.

  5. A Catalytic Method for the Conversion of Silanes to Stannanes

    DTIC Science & Technology

    1994-10-08

    tributyltin )oxide in tetrahydrofuran. The stannanes are isolated in -quantitative yields after removal of the volatile bis(trimethylsilyl)oxide in vacuc...conditions, and the resulting anion would react with bis( tributyltin )oxide. This reaction would generate a new alkoxide, and the cycle would be...This reaction utilizes inexpensive bis( tributyltin )oxide rather than the more costly and moisture-sensitive tributyltin chloride.5 The reaction allows

  6. Dense ceramic membranes for converting methane to syngas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balachandran, U.; Dusek, J.T.; Picciolo, J.J.

    1995-07-01

    Dense mixed-oxide ceramics capable of conducting both electrons and oxygen ions are promising materials for partial oxygenation of methane to syngas. We are particularly interested in an oxide based on the Sr-Fe-Co-O system. Dense ceramic membrane tubes have been fabricated by a plastic extrusion technique. The sintered tubes were then used to selectively transport oxygen from air through the membrane to make syngas without the use of external electrodes. The sintered tubes have operated for >1000 h, and methane conversion efficiencies of >98% have been observed. Mechanical properties, structural integrity of the tubes during reactor operation, results of methane conversion,more » selectivity of methane conversion products, oxygen permeation, and fabrication of multichannel configurations for large-scale production of syngas will be presented.« less

  7. Multiple hearth furnace for reducing iron oxide

    DOEpatents

    Brandon, Mark M [Charlotte, NC; True, Bradford G [Charlotte, NC

    2012-03-13

    A multiple moving hearth furnace (10) having a furnace housing (11) with at least two moving hearths (20) positioned laterally within the furnace housing, the hearths moving in opposite directions and each moving hearth (20) capable of being charged with at least one layer of iron oxide and carbon bearing material at one end, and being capable of discharging reduced material at the other end. A heat insulating partition (92) is positioned between adjacent moving hearths of at least portions of the conversion zones (13), and is capable of communicating gases between the atmospheres of the conversion zones of adjacent moving hearths. A drying/preheat zone (12), a conversion zone (13), and optionally a cooling zone (15) are sequentially positioned along each moving hearth (30) in the furnace housing (11).

  8. Chrome-free Samarium-based Protective Coatings for Magnesium Alloys

    NASA Astrophysics Data System (ADS)

    Hou, Legan; Cui, Xiufang; Yang, Yuyun; Lin, Lili; Xiao, Qiang; Jin, Guo

    The microstructure of chrome-free samarium-based conversion coating on magnesium alloy was investigated and the corrosion resistance was evaluated as well. The micro-morphology, transverse section, crystal structure and composition of the coating were observed by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and X- ray photoelectron spectroscopy (XPS), respectively. The corrosion resistance was evaluated by potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS). The results reveal that the morphology of samarium conversion coating is of crack-mud structure. Tiny cracks distribute in the compact coating deposited by samarium oxides. XRD, EDS and XPS results characterize that the coating is made of amorphous and trivalent-samarium oxides. The potentiodynamic polarization curve, EIS and OCP indicate that the samarium conversion coating can improve the corrosion resistance of magnesium alloys.

  9. Chemical Looping Technology: Oxygen Carrier Characteristics.

    PubMed

    Luo, Siwei; Zeng, Liang; Fan, Liang-Shih

    2015-01-01

    Chemical looping processes are characterized as promising carbonaceous fuel conversion technologies with the advantages of manageable CO2 capture and high energy conversion efficiency. Depending on the chemical looping reaction products generated, chemical looping technologies generally can be grouped into two types: chemical looping full oxidation (CLFO) and chemical looping partial oxidation (CLPO). In CLFO, carbonaceous fuels are fully oxidized to CO2 and H2O, as typically represented by chemical looping combustion with electricity as the primary product. In CLPO, however, carbonaceous fuels are partially oxidized, as typically represented by chemical looping gasification with syngas or hydrogen as the primary product. Both CLFO and CLPO share similar operational features; however, the optimum process configurations and the specific oxygen carriers used between them can vary significantly. Progress in both CLFO and CLPO is reviewed and analyzed with specific focus on oxygen carrier developments that characterize these technologies.

  10. Continuous Flow Aerobic Alcohol Oxidation Reactions Using a Heterogeneous Ru(OH)x/Al2O3 Catalyst

    PubMed Central

    2015-01-01

    Ru(OH)x/Al2O3 is among the more versatile catalysts for aerobic alcohol oxidation and dehydrogenation of nitrogen heterocycles. Here, we describe the translation of batch reactions to a continuous-flow method that enables high steady-state conversion and single-pass yields in the oxidation of benzylic alcohols and dehydrogenation of indoline. A dilute source of O2 (8% in N2) was used to ensure that the reaction mixture, which employs toluene as the solvent, is nonflammable throughout the process. A packed bed reactor was operated isothermally in an up-flow orientation, allowing good liquid–solid contact. Deactivation of the catalyst during the reaction was modeled empirically, and this model was used to achieve high conversion and yield during extended operation in the aerobic oxidation of 2-thiophene methanol (99+% continuous yield over 72 h). PMID:25620869

  11. Reactions of sulfur dioxide with neutral vanadium oxide clusters in the gas phase. I. Density functional theory study.

    PubMed

    Jakubikova, Elena; Bernstein, Elliot R

    2007-12-27

    Thermodynamics of reactions of vanadium oxide clusters with SO2 are studied at the BPW91/LANL2DZ level of theory. BPW91/LANL2DZ is insufficient to properly describe relative V-O and S-O bond strengths of vanadium and sulfur oxides. Calibration of theoretical results with experimental data is necessary to compute reliable enthalpy changes for reactions between VxOy and SO2. Theoretical results indicate SO2 to SO conversion occurs for oxygen-deficient clusters and SO2 to SO3 conversion occurs for oxygen-rich clusters. Stable intermediate structures of VOy (y = 1 - 4) clusters with SO2 are also obtained at the BPW91/TZVP level of theory. Some possible mechanisms for SO3 formation and catalyst regeneration for condensed-phase systems are suggested. These results are in agreement with, and complement, gas-phase experimental studies of neutral vanadium oxide clusters.

  12. ERDA/Lewis research center photovoltaic systems test facility

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Johnson, J. A.; Knapp, W. D.; Rigo, H.; Stover, J.; Suhay, R.

    1977-01-01

    A national photovoltaic power systems test facility (of initial 10-kW peak power rating) is described. It consists of a solar array to generate electrical power, test-hardware for several alternate methods of power conversion, electrical energy storage systems, and an instrumentation and data acquisition system.

  13. 7 CFR 1450.201 - Project area proposal submission requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP... a proposal to CCC that includes, at a minimum: (1) A description of the sources of renewable biomass... commitment from a biomass conversion facility stating that the facility will use, for BCAP purposes, eligible...

  14. 7 CFR 1450.201 - Project area proposal submission requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP... a proposal to CCC that includes, at a minimum: (1) A description of the sources of renewable biomass... commitment from a biomass conversion facility stating that the facility will use, for BCAP purposes, eligible...

  15. 7 CFR 1450.201 - Project area proposal submission requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP... a proposal to CCC that includes, at a minimum: (1) A description of the sources of renewable biomass... commitment from a biomass conversion facility stating that the facility will use, for BCAP purposes, eligible...

  16. 7 CFR 1450.201 - Project area proposal submission requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP... a proposal to CCC that includes, at a minimum: (1) A description of the sources of renewable biomass... commitment from a biomass conversion facility stating that the facility will use, for BCAP purposes, eligible...

  17. In Conversation with Jim Schuck: Nano-optics

    ScienceCinema

    Jim Schuck and Alice Egan

    2017-12-09

    Sponsored by Berkeley Lab's Materials Sciences Division (MSD), "In Conversation with" is a next generation science seminar series. Host Alice Egan is the assistant to MSD Director Miquel Salmeron. Alice conducts a fun and informative interview, touching on the lives and work of the guest. The first In Conversation With took place July 9 with Jim Schuck, a staff scientist in the Molecular Foundry's Imaging and Manipulation Facility as our first guest. He discussed the world of Nano-optics.

  18. In Conversation with Jim Schuck: Nano-optics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jim Schuck and Alice Egan

    Sponsored by Berkeley Lab's Materials Sciences Division (MSD), "In Conversation with" is a next generation science seminar series. Host Alice Egan is the assistant to MSD Director Miquel Salmeron. Alice conducts a fun and informative interview, touching on the lives and work of the guest. The first In Conversation With took place July 9 with Jim Schuck, a staff scientist in the Molecular Foundry's Imaging and Manipulation Facility as our first guest. He discussed the world of Nano-optics.

  19. 7 CFR 1940.311 - Environmental assessments for Class I actions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... designed for on-farm needs such as methane digestors and fuel alcohol production facilities; (5) Financial assistance for the conversion of more than 160 acres of pasture to agricultural production, but no more than 320 acres, provided that in a conversion to agricultural production no wetlands are affected, in which...

  20. 7 CFR 1940.311 - Environmental assessments for Class I actions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... designed for on-farm needs such as methane digestors and fuel alcohol production facilities; (5) Financial assistance for the conversion of more than 160 acres of pasture to agricultural production, but no more than 320 acres, provided that in a conversion to agricultural production no wetlands are affected, in which...

  1. 7 CFR 1940.311 - Environmental assessments for Class I actions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... designed for on-farm needs such as methane digestors and fuel alcohol production facilities; (5) Financial assistance for the conversion of more than 160 acres of pasture to agricultural production, but no more than 320 acres, provided that in a conversion to agricultural production no wetlands are affected, in which...

  2. 7 CFR 1940.311 - Environmental assessments for Class I actions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... designed for on-farm needs such as methane digestors and fuel alcohol production facilities; (5) Financial assistance for the conversion of more than 160 acres of pasture to agricultural production, but no more than 320 acres, provided that in a conversion to agricultural production no wetlands are affected, in which...

  3. 7 CFR 1450.214 - Annual payments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... biofuels as defined by 40 CFR 80.1401; (ii) By 10 percent if the eligible crop is delivered to a biomass conversion facility for conversion to advanced biofuels; (iii) By 25 percent if the eligible crop is..., or advanced biofuels; (2) If the producer violates a term of the contract; or (3) In other...

  4. 7 CFR 1450.214 - Annual payments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... biofuels as defined by 40 CFR 80.1401; (ii) By 10 percent if the eligible crop is delivered to a biomass conversion facility for conversion to advanced biofuels; (iii) By 25 percent if the eligible crop is..., or advanced biofuels; (2) If the producer violates a term of the contract; or (3) In other...

  5. 7 CFR 1450.214 - Annual payments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... biofuels as defined by 40 CFR 80.1401; (ii) By 10 percent if the eligible crop is delivered to a biomass conversion facility for conversion to advanced biofuels; (iii) By 25 percent if the eligible crop is..., or advanced biofuels; (2) If the producer violates a term of the contract; or (3) In other...

  6. 7 CFR 1450.214 - Annual payments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... biofuels as defined by 40 CFR 80.1401; (ii) By 10 percent if the eligible crop is delivered to a biomass conversion facility for conversion to advanced biofuels; (iii) By 25 percent if the eligible crop is..., or advanced biofuels; (2) If the producer violates a term of the contract; or (3) In other...

  7. SECOND-YEAR YORUBA BOUND WITH SECOND-YEAR YORUBA INFORMANT'S MANUAL.

    ERIC Educational Resources Information Center

    AREMU, J.O.; WOLFF, HANS

    AN INTERMEDIATE LEVEL TEXT WAS COMPILED FOR 2D-YEAR YORUBA STUDENTS. THE MATERIALS WERE DESIGNED TO IMPROVE THE STUDENT'S CONVERSATIONAL FACILITY. THE PRESENT WORK PRESENTS SEQUENCES AND CONSTRUCTIONS WHICH ARE CHARACTERISTIC OF YORUBA CONVERSATIONAL STYLE AND OF EXTENDED DISCOURSE SUCH AS IS FOUND IN STORIES, FOLKTALES, AND DESCRIPTIVE ACCOUNTS.…

  8. 77 FR 42653 - United States Navy Restricted Area, SUPSHIP Gulf Coast Detachment Mobile at AUSTAL, USA, Mobile...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ... restricted area established around the AUSTAL, USA shipbuilding facility located in Mobile, Alabama. The Supervisor of Shipbuilding, Conversion and Repair, United States Navy (USN), Gulf Coast (SUPSHIP Gulf Coast..., 2011, replacing the Supervisor of Shipbuilding, Conversion, and Repair, USN, Bath (SUPSHIP Bath). The...

  9. Review of the TREAT Conversion Conceptual Design and Fuel Qualification Plan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Diamond, David

    The U.S. Department of Energy (DOE) is preparing to re establish the capability to conduct transient testing of nuclear fuels at the Idaho National Laboratory (INL) Transient Reactor Test (TREAT) facility. The original TREAT core went critical in February 1959 and operated for more than 6,000 reactor startups before plant operations were suspended in 1994. DOE is now planning to restart the reactor using the plant's original high-enriched uranium (HEU) fuel. At the same time, the National Nuclear Security Administration (NNSA) Office of Material Management and Minimization Reactor Conversion Program is supporting analyses and fuel fabrication studies that will allowmore » for reactor conversion to low-enriched uranium (LEU) fuel (i.e., fuel with less than 20% by weight 235U content) after plant restart. The TREAT Conversion Program's objectives are to perform the design work necessary to generate an LEU replacement core, to restore the capability to fabricate TREAT fuel element assemblies, and to implement the physical and operational changes required to convert the TREAT facility to use LEU fuel.« less

  10. Facile synthesis of highly stable and well-dispersed mesoporous ZrO(2)/carbon composites with high performance in oxidative dehydrogenation of ethylbenzene.

    PubMed

    Li, Qiang; Xu, Jie; Wu, Zhangxiong; Feng, Dan; Yang, Jianping; Wei, Jing; Wu, Qingling; Tu, Bo; Cao, Yong; Zhao, Dongyuan

    2010-09-28

    Highly ordered mesoporous ZrO(2)/carbon (FDU-15) composites have been synthesized via a facile evaporation induced triconstituent co-assembly (EISA) approach by using Pluronic F127 as a template and zirconium oxychloride octahydrate and resol as Zr and carbon sources. The synthesized mesoporous composites exhibit a highly ordered two-dimensional (2-D) hexagonal mesostructure with relatively high specific surface areas (up to 947 m(2) g(-1)), pore sizes around 3.8 nm and high pore volumes (up to 0.71 cm(3) g(-1)). The results clearly show that the crystalline zirconia nanoparticles (ca. 1.9-3.9 nm) are well-dispersed in amorphous matrices of the ordered mesoporous carbon FDU-15 materials, which construct the nanocomposites. The ordered mesostructures of the obtained ZrO(2)/FDU-15 composites can be well-retained even at the high pyrolysis temperature (up to 900 degrees C), suggesting a high thermal stability. The zirconia content of the ZrO(2)/FDU-15 composites can be tunable in a wide range (up to 47%). Moreover, the resultant mesoporous ZrO(2)/FDU-15 composites exhibit high catalytic activity in oxidative dehydrogenation (ODH) of ethylbenzene (EB) to styrene (ST), with high ethylbenzene conversion (59.6%) and styrene selectivity (90.4%), which is mainly attributed to the synergistic catalytic effect between the oxygen-containing groups located on the carbon pore walls and weakly basic sites of the nanocrystalline ZrO(2). Furthermore, the high specific surface areas and opening pore channels are also responsible for their high catalytic activity. Therefore, it is a very promising catalyst material in styrene production on an industrial scale.

  11. Investigation of advanced nanostructured multijunction photoanodes for enhanced solar hydrogen generation via water splitting

    NASA Astrophysics Data System (ADS)

    Ishihara, Hidetaka

    As the worldwide demand for fossil-based fuel increases every day and the fossil reserve continues to be depleted, the need for alternative/renewable energy sources has gained momentum. Electric, hybrid, and hydrogen cars have been at the center of discussion lately among consumers, automobile manufacturers, and politicians, alike. The development of a fuel-cell based engine using hydrogen has been an ambitious research area over the last few decades-ever since Fujishima showed that hydrogen can be generated via the solar-energy driven photo-electrolytic splitting of water. Such solar cells are known as Photo-Electro-Chemical (PEC) solar cells. In order to commercialize this technology, various challenges associated with photo-conversion efficiency, chemical corrosion resistance, and longevity need to be overcome. In general, metal oxide semiconductors such as titanium dioxide (TiO 2, titania) are excellent candidates for PEC solar cells. Titania nanotubes have several advantages, including biocompatibility and higher chemical stability. Nevertheless, they can absorb only 5-7% of the solar spectrum which makes it difficult to achieve the higher photo-conversion efficiency required for successful commercial applications. A two-prong approach was employed to enhance photo-conversion efficiency: 1) surface modification of titania nanotubes using plasma treatment and 2) nano-capping of the titania nanotubes using titanium disilicide. The plasma surface treatment with N2 was found to improve the photo-current efficiency of titania nanotubes by 55%. Similarly, a facile, novel approach of nano-capping titania nanotubes to enhance their photocurrent response was also investigated. Electrochemically anodized titania nanotubes were capped by coating a 25 nm layer of titanium disilicide using RF magnetron sputtering technique. The optical properties of titania nanotubes were not found to change due to the capping; however, a considerable increase (40%) in the photocurrent density was observed for the nano-capped titania nanotubes due to the enhanced charge transfer process. Similarly, another metal oxide semiconductor was investigated tungsten trioxide (WO3), which has a much higher absorption capability (12%) in the solar spectrum. The WO3 porous nanostructures suffered from surface corrosion resulting in a large reduction in the photocurrent density as a function of time in the alkaline electrolytes. However, with a protective coating of Indium Tin Oxide (100 nm), the surface corrosion of WO3 porous nanostructures was reduced. A large increase in the photocurrent density of as much as 340% was observed after the ITO was applied to the WO3 porous nanostructures

  12. NITRIC OXIDE FORMATION DURING PULVERIZED COAL COMBUSTION

    EPA Science Inventory

    Data on the overall conversion of coal-nitrogen to NOx were obtained at 1250 K and 1750 K for a residence time of one second. The conversion of coal-nitrogen to NOx decreased monotonically with increasing fuel/oxygen equivalence ratio and decreased slightly with increasing temper...

  13. Cultural analysis of communication behaviors among juveniles in a correctional facility.

    PubMed

    Sanger, D D; Creswell, J W; Dworak, J; Schultz, L

    2000-01-01

    This study addressed communication behaviors of female juvenile delinquents in a correctional facility. Qualitative methodology was used to study 78 participants ranging in age from 13.1 to 18.9 (years; months), over a five-month period. Data collection consisted of observations, participant observation, interviews, and a review of documents. Additionally, participants were tested on the Clinical Evaluation of Language Fundamentals-3. Listening and following rules, utterance types, topics of conversion, politeness, and conversational management emerged as themes. Findings indicated that as many as 22% of participants were potential candidates for language services. Implications for speech-language pathologists (SLPs) providing communication services will be provided.

  14. Development of a decision model for the techno-economic assessment of municipal solid waste utilization pathways.

    PubMed

    Khan, Md Mohib-Ul-Haque; Jain, Siddharth; Vaezi, Mahdi; Kumar, Amit

    2016-02-01

    Economic competitiveness is one of the key factors in making decisions towards the development of waste conversion facilities and devising a sustainable waste management strategy. The goal of this study is to develop a framework, as well as to develop and demonstrate a comprehensive techno-economic model to help county and municipal decision makers in establishing waste conversion facilities. The user-friendly data-intensive model, called the FUNdamental ENgineering PrinciplEs-based ModeL for Estimation of Cost of Energy and Fuels from MSW (FUNNEL-Cost-MSW), compares nine different waste management scenarios, including landfilling and composting, in terms of economic parameters such as gate fees and return on investment. In addition, a geographic information system (GIS) model was developed to determine suitable locations for waste conversion facilities and landfill sites based on integration of environmental, social, and economic factors. Finally, a case study on Parkland County and its surrounding counties in the province of Alberta, Canada, was conducted and a sensitivity analysis was performed to assess the influence of the key technical and economic parameters on the calculated results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Flume experiments elucidate relationships between microbial genetics, nitrogen species and hydraulics in controlling nitrous oxide production in the hyporheic zone

    NASA Astrophysics Data System (ADS)

    Quick, A. M.; Farrell, T. B.; Reeder, W. J.; Feris, K. P.; Tonina, D.; Benner, S. G.

    2014-12-01

    The hyporheic zone is a potentially important producer of nitrous oxide, a powerful greenhouse gas. The location and magnitude of nitrous oxide generation within the hyporheic zone involves complex interactions between multiple nitrogen species, redox conditions, microbial communities, and hydraulics. To better understand nitrous oxide generation and emissions from streams, we conducted large-scale flume experiments in which we monitored pore waters along hyporheic flow paths within stream dune structures. Measured dissolved oxygen, ammonia, nitrate, nitrite, and dissolved nitrous oxide showed distinct spatial relationships reflecting redox changes along flow paths. Denitrifying genes (nosZ, nirS, and nirK), determined using qPCR, were spatially associated with abundances of nitrogen species. Using residence times along a flow path, clear trends in oxygen conditions, genes encoding for microbial catalysis, and nitrogen species were observed. Hotspots of targeted genes correlated with hotspots for conversion of nitrogen species, including nitrous oxide production and conversion to dinitrogen. Trends were apparent regardless of dune size, allowing for the possibility to apply observed relationships to multiple streambed morphologies. Relating streambed morphology and loading of nitrogen species allows for prediction of nitrous oxide production in the hyporheic zone.

  16. Facile electrodeposition of reduced graphene oxide hydrogels for high-performance supercapacitors

    NASA Astrophysics Data System (ADS)

    Pham, Viet Hung; Gebre, Tesfaye; Dickerson, James H.

    2015-03-01

    We report both a facile, scalable method to prepare reduced graphene oxide hydrogels through the electrodeposition of graphene oxide and its use as an electrode for high-performance supercapacitors. Such systems exhibited specific capacitances of 147 and 223 F g-1 at a current density of 10 A g-1 when using H2SO4 and H2SO4 + hydroquinone redox electrolytes, respectively.We report both a facile, scalable method to prepare reduced graphene oxide hydrogels through the electrodeposition of graphene oxide and its use as an electrode for high-performance supercapacitors. Such systems exhibited specific capacitances of 147 and 223 F g-1 at a current density of 10 A g-1 when using H2SO4 and H2SO4 + hydroquinone redox electrolytes, respectively. Electronic supplementary information (ESI) available: GO synthesis, characterization, fabrication of ERGO supercapacitor and electrochemical measurement, elemental composition, TGA and XRD of GO and ERGO. See DOI: 10.1039/c4nr07508k

  17. View of North End of Oxide Building Interior Including Roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of North End of Oxide Building Interior Including Roof and Wall Juncture and Crane Trolley - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  18. Enhanced photo-catalytic activity of ordered mesoporous indium oxide nanocrystals in the conversion of CO2 into methanol.

    PubMed

    Gondal, M A; Dastageer, M A; Oloore, L E; Baig, U; Rashid, S G

    2017-07-03

    Ordered mesoporous indium oxide nanocrystal (m-In 2 O 3 ) was synthesized by nanocasting technique, in which highly ordered mesoporous silca (SBA-15) was used as structural matrix. X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halanda (BJH) studies were carried out on m-In 2 O 3 and the results revealed that this material has a highly ordered mesoporous surface with reduced grain size, increased surface area and surface volume compared to the non porous indium oxide. The diffuse reluctance spectrum exhibited substantially improved light absorption efficiency in m-In 2 O 3 compared to normal indium oxide, however, no considerable change in the band gap energies of these materials was observed. When m-In 2 O 3 was used as a photo-catalyst in the photo-catalytic process of converting carbon dioxide (CO 2 ) into methanol under the pulsed laser radiation of 266-nm wavelengths, an enhanced photo-catalytic activity with the quantum efficiency of 4.5% and conversion efficiency of 46.3% were observed. It was found that the methanol production yield in this chemical process is as high as 485 µlg -1 h -1 after 150 min of irradiation, which is substantially higher than the yields reported in the literature. It is quite clear from the results that the introduction of mesoporosity in indium oxide, and the consequent enhancement of positive attributes required for a photo-catalyst, transformed photo-catalytically weak indium oxide into an effective photo-catalyst for the conversion of CO 2 into methanol.

  19. Production of Chromium Oxide from Turkish Chromite Concentrate Using Ethanol

    NASA Astrophysics Data System (ADS)

    Aktas, S.; Eyuboglu, C.; Morcali, M. H.; Özbey, S.; Sucuoglu, Y.

    2015-05-01

    In this study, the possibility of chromium extraction from Turkish chromite concentrate and the production of chromium oxide were investigated. For the conversion of chromium(III) into chromium(VI), NaOH was employed, as well as air with a rate of 20 L/min. The effects of the base amount, fusing temperature, and fusing time on the chromium conversion percentage were investigated in detail. The conversion kinetics of chromium(III) to chromium(VI) was also undertaken. Following the steps of dissolving the sodium chromate in water and filtering, aluminum hydroxide was precipitated by adjusting the pH level of the solution. The chromium(VI) solution was subsequently converted to Cr(III) by the combination of sulfuric acid and ethanol. Interestingly, it was observed that ethanol precipitated chromium as chromium(VI) at mildly acidic pH levels, although this effect is more pronounced for K2Cr2O7 than Na2Cr2O7. On the other hand, in the strongly acidic regime, ethanol acted as a reducing agent role in that chromium(VI) was converted into Cr(III) whereas ethanol itself was oxidized to carbon dioxide and water. Subsequently, chromium hydroxide was obtained by the help of sodium hydroxide and converted to chromium oxide by heating at 800 °C, as indicated in thermo gravimetric analysis (TGA).

  20. Effect of substrate availability on nitrous oxide production by deammonification processes under anoxic conditions

    PubMed Central

    Schneider, Yvonne; Beier, Maike; Rosenwinkel, Karl‐Heinz

    2012-01-01

    Summary Due to its high global warming potential, nitrous oxide (N2O) emissions from wastewater treatment processes have recently received a high degree of attention. Nevertheless, there is still a lack of information regarding the microbiological processes leading to N2O production. In this study, two lab‐scale sequencing batch reactors were operated with deammonification biomass to investigate the role of denitrification and the influence of substrate availability regarding N2O formation during the anoxic phase of deammonification. Three different operational phases were established: within the first phase conversion by anammox was favoured and after a transition phase, denitrification activity was promoted. Low nitrous oxide production was observed during stable operation aiming for anammox conversion. Pulsed inflow of the wastewater containing ammonium (NH4+) and nitrite (NO2‐) led to increased N2O production rates. Within the period of denitrification as dominating nitrogen conversion process, the nitrous oxide concentration level was higher during continuous inflow conditions, but the reaction to pulsed inflow was less pronounced. The results indicated that denitrification was responsible for N2O formation from the deammonification biomass. Operational settings to achieve suppression of denitrification processes to a large extend were deducted from the results of the experiments. PMID:22296600

  1. Pollution prevention and the use of low-VOC/HAP coatings at wood furniture manufacturing facilities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marshall, A.M.; Spaight, J.L.; Jones, J.W.

    1999-07-01

    Midwest Research Institute, under a cooperative agreement with the Air Pollution Prevention and Control Division of the U.S. Environmental Protection Agency's (EPA's) National Risk Management Research Laboratory, is conducting a study to identify wood furniture and cabinet manufacturing facilities that have converted to low-volatile organic compound/hazardous air pollutant (VOC/HAP) coatings and to develop case studies for those facilities. The case studies include: (1) a discussion of the types of products each facility manufactures; (2) the types of low-VOC/HAP coatings each facility is using; (3) problems encountered in converting to low-VOC/HAP coatings; (4) equipment changes that were required; (5) the costsmore » associated with the conversion process, including capital costs associated with equipment purchases, research and development costs, and operating costs such as operator training in new application techniques; (6) advantages/disadvantages of the low-VOC/HAP coatings; and (7) customer feedback on products finished with the low-VOC/HAP coatings. The primary goals of the project are (1) to demonstrate that low-VOC/HAP coatings can be used successfully by many wood furniture manufacturing facilities, and (2) to assist other wood furniture manufacturing facilities in their conversion to low-VOC/HAP coatings, in particular facilities that do not have the resources to devote to extensive coatings research. This paper discusses the progress of the project and pollution prevention options at wood furniture manufacturing facilities and the regulatory requirements (e.g., the National Emissions Standards for Hazardous Air Pollutants [NESHAP] for Wood Furniture Manufacturing Operations) that these facilities face.« less

  2. Knocking on wood: base metal complexes as catalysts for selective oxidation of lignin models and extracts.

    PubMed

    Hanson, Susan K; Baker, R Tom

    2015-07-21

    This work began as part of a biomass conversion catalysis project with UC Santa Barbara funded by the first NSF Chemical Bonding Center, CATSB. Recognizing that catalytic aerobic oxidation of diol C-C bonds could potentially be used to break down lignocellulose, we began to synthesize oxovanadium complexes and explore their fundamental reactivity. Of course there were theories regarding the oxidation mechanism, but our mechanistic studies soon revealed a number of surprises of the type that keep all chemists coming back to the bench! We realized that these reactions were also exciting in that they actually used the oxygen-on-every-carbon property of biomass-derived molecules to control the selectivity of the oxidation. When we found that these oxovanadium complexes tended to convert sugars predominantly to formic acid and carbon dioxide, we replaced one of the OH groups with an ether and entered the dark world of lignin chemistry. In this Account, we summarize results from our collaboration and from our individual labs. In particular, we show that oxidation selectivity (C-C vs C-O bond cleavage) of lignin models using air and vanadium complexes depends on the ancillary ligands, the reaction solvent, and the substrate structure (i.e., phenolic vs non-phenolic). Selected vanadium complexes in the presence of added base serve as effective alcohol oxidation catalysts via a novel base-assisted dehydrogenation pathway. In contrast, copper catalysts effect direct C-C bond cleavage of these lignin models, presumably through a radical pathway. The most active vanadium catalyst exhibits unique activity for the depolymerization of organosolv lignin. After Weckhuysen's excellent 2010 review on lignin valorization, the number of catalysis studies and approaches on both lignin models and extracts has expanded rapidly. Today we are seeing new start-ups and lignin production facilities sprouting up across the globe as we all work to prove wrong the old pulp and paper chemist's adage: you can make anything from lignin except money!

  3. Computational studies of small neutral vanadium oxide clusters and their reactions with sulfur dioxide

    NASA Astrophysics Data System (ADS)

    Jakubikova, Elena; He, Sheng-Gui; Xie, Yan; Matsuda, Yoshiyuki; Bernstein, Elliot

    2007-03-01

    Vanadium oxide is a catalytic system that plays an important role in the conversion of SO2 to SO3. Density functional theory at the BPW91/LANL2DZ level is employed to obtain structures of VOy (y=1,,5), V2Oy (y=2,,7), V3Oy (y=4,,9), V4Oy (y=7,,12) and their complexes with SO2. BPW91/LANL2DZ is insufficient to describe properly relative V-O and S-O bond strengths of vanadium and sulfur oxides. Calibration of theoretical results with experimental data is necessary to compute enthalpies of reactions between VxOy and SO2. Theoretical results indicate SO2 to SO conversion occurs for oxygen-deficient clusters and SO2 to SO3 conversion occurs for oxygen-rich clusters. Subsequent experimental studies confirm the presence of SO in the molecular beam as well as the presence of VxOy complexes with SO2. Some possible mechanisms for SO3 formation and catalyst regeneration for solids are also suggested.

  4. Device physics of Cu(In,Ga)Se2 solar cells for long-term operation

    NASA Astrophysics Data System (ADS)

    Nishinaga, J.; Shibata, H.

    2017-02-01

    The degradation mechanism of Cu(In,Ga)Se2 (CIGS) solar cells on exposure to air has been investigated. Exposure to air at room temperature slightly reduces the conversion efficiency of CIGS solar cells, and the conversion efficiency decreases significantly under damp heat testing at 85 °C and 85% relative humidity due to low shunt resistance. On the other hand, shunt resistance increases after dry nitrogen heating. Therefore, oxygen and humidity should degenerate the solar cell performance. The low shunt resistance and conversion efficiency are completely recovered after removing the side edges of the CIGS solar cells by mechanical scribing. These results suggest that low-resistive layers are formed on the sidewalls of the solar cells during damp heat testing. The low-resistive layers on the sidewalls are identified to be molybdenum oxides and sodium molybdate by Auger electron spectroscopy. After etching the oxides on the sidewalls by alkaline solution, the saturation current density and ideality factor are confirmed to be improved. These results suggest that metal oxides on the sidewalls of CIGS solar cells may act as recombination centers.

  5. Long vertically aligned titania nanotubes on transparent conducting oxide for highly efficient solar cells.

    PubMed

    Varghese, Oomman K; Paulose, Maggie; Grimes, Craig A

    2009-09-01

    Dye-sensitized solar cells consist of a random network of titania nanoparticles that serve both as a high-surface-area support for dye molecules and as an electron-transporting medium. Despite achieving high power conversion efficiencies, their performance is limited by electron trapping in the nanoparticle film. Electron diffusion lengths can be increased by transporting charge through highly ordered nanostructures such as titania nanotube arrays. Although titania nanotube array films have been shown to enhance the efficiencies of both charge collection and light harvesting, it has not been possible to grow them on transparent conducting oxide glass with the lengths needed for high-efficiency device applications (tens of micrometres). Here, we report the fabrication of transparent titania nanotube array films on transparent conducting oxide glass with lengths between 0.3 and 33.0 microm using a novel electrochemistry approach. Dye-sensitized solar cells containing these arrays yielded a power conversion efficiency of 6.9%. The incident photon-to-current conversion efficiency ranged from 70 to 80% for wavelengths between 450 and 650 nm.

  6. Visible-light-responsive photocatalysts toward water oxidation based on NiTi-layered double hydroxide/reduced graphene oxide composite materials.

    PubMed

    Li, Bei; Zhao, Yufei; Zhang, Shitong; Gao, Wa; Wei, Min

    2013-10-23

    A visible-light responsive photocatalyst was fabricated by anchoring NiTi-layered double hydroxide (NiTi-LDH) nanosheets to the surface of reduced graphene oxide sheets (RGO) via an in situ growth method; the resulting NiTi-LDH/RGO composite displays excellent photocatalytic activity toward water splitting into oxygen with a rate of 1.968 mmol g(-1) h(-1) and a quantum efficiency as high as 61.2% at 500 nm, which is among the most effective visible-light photocatalysts. XRD patterns and SEM images indicate that the NiTi-LDH nanosheets (diameter: 100-200 nm) are highly dispersed on the surface of RGO. UV-vis absorption spectroscopy exhibits that the introduction of RGO enhances the visible-light absorption range of photocatalysts, which is further verified by the largely decreased band gap (∼1.78 eV) studied by cyclic voltammetry measurements. Moreover, photoluminescence (PL) measurements indicate a more efficient separation of electron-hole pairs; electron spin resonance (ESR) and Raman scattering spectroscopy confirm the electrons transfer from NiTi-LDH nanosheets to RGO, accounting for the largely enhanced carrier mobility and the resulting photocatalytic activity in comparison with pristine NiTi-LDH material. Therefore, this work demonstrates a facile approach for the fabrication of visible-light responsive NiTi-LDH/RGO composite photocatalysts, which can be used as a promising candidate in solar energy conversion and environmental science.

  7. Transparent conducting oxide-free nitrogen-doped graphene/reduced hydroxylated carbon nanotube composite paper as flexible counter electrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Jindan; Yu, Mei; Li, Songmei; Meng, Yanbing; Wu, Xueke; Liu, Jianhua

    2016-12-01

    Three-dimensional nitrogen-doped graphene/reduced hydroxylated carbon nanotube composite aerogel (NG/CNT-OH) with unique hierarchical porosity and mechanical stability is developed through a two-step hydrothermal reaction. With plenty of exposed active sites and efficient multidimensional transport pathways of electrons and ions, NG/CNT-OH exhibits great electrocatalytic performances for I-/I3- redox couple. The subsequent compressed NG/CNT-OH papers possess high electrical conductivity and good flexibility, thus generating high-performance flexible counter electrodes (CEs) with transparent conducting oxide free (TCO-free) for dye-sensitized solar cells (DSSCs). The flexible NG/CNT-OH electrodes show good stability and the DSSCs with the optimized NG/CNT-OH CE had higher short-circuit current density (13.62 mA cm-2) and cell efficiency (6.36%) than DSSCs using Pt CE, whereas those of the DSSCs using Pt CE were only 12.81 mA cm-2 and 5.74%, respectively. Increasing the ratio of hydroxylated carbon nanotubes (CNT-OH) to the graphene oxide (GO) in the reactant would lead to less content of doped N, but better diffusion of electrolyte in the CEs because of more complete GO etching reaction. The design strategy presents a facile and cost effective way to synthesis three-dimensional graphene/CNT composite aerogel with excellent performance, and it can be potentially used as flexible TCO-free CE in other power conversion or energy storage devices.

  8. One-Step Laser Patterned Highly Uniform Reduced Graphene Oxide Thin Films for Circuit-Enabled Tattoo and Flexible Humidity Sensor Application.

    PubMed

    Park, Rowoon; Kim, Hyesu; Lone, Saifullah; Jeon, Sangheon; Kwon, Young Woo; Shin, Bosung; Hong, Suck Won

    2018-06-06

    The conversion of graphene oxide (GO) into reduced graphene oxide (rGO) is imperative for the electronic device applications of graphene-based materials. Efficient and cost-effective fabrication of highly uniform GO films and the successive reduction into rGO on a large area is still a cumbersome task through conventional protocols. Improved film casting of GO sheets on a polymeric substrate with quick and green reduction processes has a potential that may establish a path to the practical flexible electronics. Herein, we report a facile deposition process of GO on flexible polymer substrates to create highly uniform thin films over a large area by a flow-enabled self-assembly approach. The self-assembly of GO sheets was successfully performed by dragging the trapped solution of GO in confined geometry, which consisted of an upper stationary blade and a lower moving substrate on a motorized translational stage. The prepared GO thin films could be selectively reduced and facilitated from the simple laser direct writing process for programmable circuit printing with the desired configuration and less sample damage due to the non-contact mode operation without the use of photolithography, toxic chemistry, or high-temperature reduction methods. Furthermore, two different modes of the laser operating system for the reduction of GO films turned out to be valuable for the construction of novel graphene-based high-throughput electrical circuit boards compatible with integrating electronic module chips and flexible humidity sensors.

  9. All About MOX

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2009-07-29

    In 1999, the Nuclear Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

  10. All About MOX

    ScienceCinema

    None

    2018-01-16

    In 1999, the Nuclear Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

  11. Metal Nanoshells for Plasmonically Enhanced Solar to Fuel Photocatalytic Conversion

    DTIC Science & Technology

    2016-05-18

    interlayer of ~17 nm generated a rate of hydrogen production 2.6 times higher than that of unmodified ZIS. Second thrust: Tin oxide-coated gold-silver...nanoshells were prepared as an alternative plasmonic enhancement system to the silicon oxide system described above. Tin oxide is an attractive...this grant, we developed two synthetic approaches for preparing tin oxide-coated gold-silver nanoshells, as illustrated in Scheme 2. These particles

  12. Neuropsychological Outcomes in Fatty Acid Oxidation Disorders: 85 Cases Detected by Newborn Screening

    ERIC Educational Resources Information Center

    Waisbren, Susan E.; Landau, Yuval; Wilson, Jenna; Vockley, Jerry

    2013-01-01

    Mitochondrial fatty acid oxidation disorders include conditions in which the transport of activated acyl-Coenzyme A (CoA) into the mitochondria or utilization of these substrates is disrupted or blocked. This results in a deficit in the conversion of fat into energy. Most patients with fatty acid oxidation defects are now identified through…

  13. Looking Northeast in Oxide Building at Reactors on Second Floor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Northeast in Oxide Building at Reactors on Second Floor Including Reactor One (Left) and Reactor Two (Right) - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  14. In situ X-ray diffraction characterization of NiSe2 as a promising anode material for sodium ion batteries

    NASA Astrophysics Data System (ADS)

    Ou, Xing; Li, Jiao; Zheng, Fenghua; Wu, Peng; Pan, Qichang; Xiong, Xunhui; Yang, Chenghao; Liu, Meilin

    2017-03-01

    Reduced graphene oxide (rGO) homogenously wrapped nickel diselenide (NiSe2/rGO) hybrid has been prepared by a facile one-spot hydrothermal method. When investigated as anode material for sodium ion batteries (SIBs), NiSe2/rGO hybrid delivers a high reversible capacity (433 mAh g-1 at 100 mA g-1), superior rate performance (406, 386, 366, 347 and 318 mAh g-1 at 200, 500, 1000, 2000 and 5000 mA g-1, respectively) and excellent cycling stability (a capacity retention of 346 mAh g-1 after 1000 cycles at 1000 mA g-1) within the 0.4-3.0 V voltage range. In situ XRD analysis and ex situ SEM/TEM measurement reveal that the high capacity of NiSe2/rGO is originated from the combined Na+ intercalation and conversion reactions. These results validate the impact of voltage range on electrochemical property, providing a new route to rationalize the limiting factors that affect the performance of NiSe2 anode material. The facile synthesis and superior electrochemical performance of the NiSe2/rGO hybrid render it a promising anode material for SIBs.

  15. Ultrasound-assisted oxidation of dibenzothiophene with phosphotungstic acid supported on activated carbon.

    PubMed

    Liu, Liyan; Zhang, Yu; Tan, Wei

    2014-05-01

    Phosphotungstic acid (HPW) supported on activated carbon (AC) was applied to catalyze deep oxidation desulfurization of fuel oil with the assist of ultrasound. The sulfur-conversion rate was evaluated by measuring the concentration of dibenzothiophene (DBT) in n-octane before and after the oxidation. Supporting HPW on AC has been verified to play a positive role in UAOD process by a series of contrast tests, where only HPW, AC or a mixture of free HPW and AC was used. The influences of catalyst dose, ultrasound power, reaction temperature, H2O2:oil volume ratio and the reuse of catalyst on the catalytic oxidation desulfurization kinetics were investigated. The DBT conversion rate of the reaction catalyzed by supported HPW under ultrasound irradiation was higher than the summation of the reactions with HPW only and AC only as catalyst. With the increase of loading amount of HPW on AC, ultrasound power, H2O2:oil volume ratio and reaction temperature, the catalytic oxidation reactivity of DBT would be enhanced. The optimum loading amount of HPW was 10%, exceed which DBT conversion would no longer increase obviously. DBT could be completely converted under the optimized conditions (volume ratio of H2O2 to model oil: 1:10, mass ratio of the supported HPW to model oil: 1.25%, temperature: 70°C) after 9 min of ultrasound irradiation. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Multicolor up conversion emission and color tunability in Yb 3+/Tm 3+/Ho 3+ triply doped heavy metal oxide glasses

    NASA Astrophysics Data System (ADS)

    Ledemi, Yannick; Manzani, Danilo; Ribeiro, Sidney J. L.; Messaddeq, Younes

    2011-10-01

    Multicolor and white light emissions have been achieved in Yb 3+, Tm 3+ and Ho 3+ triply doped heavy metal oxide glasses upon laser excitation at 980 nm. The red (660 nm), green (547 nm) and blue (478 nm) up conversion emissions of the rare earth (RE) ions triply doped TeO 2-GeO 2-Bi 2O 3-K 2O glass (TGBK) have been investigated as a function of the RE concentration and excitation power of the 980 nm laser diode. The most appropriate combination of RE in the TGBK glass host (1.6 wt% Yb 2O 3, 0.6 wt% Tm 2O 3 and 0.1 wt% Ho 2O 3) has been determined with the purpose to tune the primary colors (RGB) respective emissions and generate white light emission by varying the pump power. The involved infrared to visible up conversion mechanisms mainly consist in a three-photon blue up conversion of Tm 3+ ions and a two-photon green and red up conversions of Ho 3+ ions. The resulting multicolor emissions have been described according to the CIE-1931 standards.

  17. Redox Conversion of Chromium(VI) and Arsenic(III) with the Intermediates of Chromium(V) and Arsenic(IV) via AuPd/CNTs Electrocatalysis in Acid Aqueous Solution.

    PubMed

    Sun, Meng; Zhang, Gong; Qin, Yinghua; Cao, Meijuan; Liu, Yang; Li, Jinghong; Qu, Jiuhui; Liu, Huijuan

    2015-08-04

    Simultaneous reduction of Cr(VI) to Cr(III) and oxidation of As(III) to As(V) is a promising pretreatment process for the removal of chromium and arsenic from acid aqueous solution. In this work, the synergistic redox conversion of Cr(VI) and As(III) was efficiently achieved in a three-dimensional electrocatalytic reactor with synthesized AuPd/CNTs particles as electrocatalysts. The AuPd/CNTs facilitated the exposure of active Pd{111} facets and possessed an approximate two-electron-transfer pathway of oxygen reduction with the highly efficient formation of H2O2 as end product, resulting in the electrocatalytic reduction of 97.2 ± 2.4% of Cr(VI) and oxidation of 95.7 ± 4% of As(III). The electrocatalytic reduction of Cr(VI) was significantly accelerated prior to the electrocatalytic oxidation of As(III), and the effectiveness of Cr(VI)/As(III) conversion was favored at increased currents from 20 to 150 mA, decreased initial pH from 7 to 1 and concentrations of Cr(VI) and As(III) ranging from 50 to 1 mg/L. The crucial intermediates of Cr(V) and As(IV) and active free radicals HO(•) and O2(•-) were found for the first time, whose roles in the control of Cr(VI)/As(III) redox conversion were proposed. Finally, the potential applicability of AuPd/CNTs was revealed by their stability in electrocatalytic conversion over 10 cycles.

  18. Uranium Quick Facts

    Science.gov Websites

    about this project and web site. your e-mail address Sign Me Up Search: OK Button DUF6 Guide DU Uses DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home  -mail icon E-mail to a friend DUF6 Guide | DU Uses | DUF6 Management | DUF6 Conversion Facility EISs

  19. Conjugated Polymers Atypically Prepared in Water

    PubMed Central

    Invernale, Michael A.; Pendergraph, Samuel A.; Yavuz, Mustafa S.; Ombaba, Matthew; Sotzing, Gregory A.

    2010-01-01

    Processability remains a fundamental issue for the implementation of conducting polymer technology. A simple synthetic route towards processable precursors to conducting polymers (main chain and side chain) was developed using commercially available materials. These soluble precursor systems were converted to conjugated polymers electrochemically in aqueous media, offering a cheaper and greener method of processing. Oxidative conversion in aqueous and organic media each produced equivalent electrochromics. The precursor method enhances the yield of the electrochromic polymer obtained over that of electrodeposition, and it relies on a less corruptible electrolyte bath. However, electrochemical conversion of the precursor polymers often relies on organic salts and solvents. The ability to achieve oxidative conversion in brine offers a less costly and a more environmentally friendly processing step. It is also beneficial for biological applications. The electrochromics obtained herein were evaluated for electronic, spectral, and morphological properties. PMID:20959869

  20. Method for regeneration and activity improvement of syngas conversion catalyst

    DOEpatents

    Lucki, Stanley J.; Brennan, James A.

    1980-01-01

    A method is disclosed for the treatment of single particle iron-containing syngas (synthes.s gas) conversion catalysts comprising iron, a crystalline acidic aluminosilicate zeolite having a silica to alumina ratio of at least 12, a pore size greater than about 5 Angstrom units and a constraint index of about 1-12 and a matrix. The catalyst does not contain promoters and the treatment is applicable to either the regeneration of said spent single particle iron-containing catalyst or for the initial activation of fresh catalyst. The treatment involves air oxidation, hydrogen reduction, followed by a second air oxidation and contact of the iron-containing single particle catalyst with syngas prior to its use for the catalytic conversion of said syngas. The single particle iron-containing catalysts are prepared from a water insoluble organic iron compound.

  1. Looking Southwest at First Floor View of Oxide Building Interior ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest at First Floor View of Oxide Building Interior Including Steam Lines, Weigh and Sample Hood, and Superheater - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  2. Transition metal sulfide loaded catalyst

    DOEpatents

    Maroni, Victor A.; Iton, Lennox E.; Pasterczyk, James W.; Winterer, Markus; Krause, Theodore R.

    1994-01-01

    A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  3. Massachusetts Lowell low speed wind tunnel (LSWT) test section

    NASA Astrophysics Data System (ADS)

    Anderson, Erik William

    The alumina and hybrid alumina-silica FT catalyst were prepared by one-step solgel/oil-drop methods using metal-nitrate-solutions (method-I), and nanoparticle-metaloxides (method-2). The nanoparticle-metal-oxides did not participate in solubility equilibria in contrast to metal nitrate in method-1 causing no metal ion seepage; therefore, method-2 yields higher XRF metal loading efficiency than method-1. The thermal analysis confirmed that the metal loading by method-1 and method-2 involved two different pathways. Method-1 involves solubility equilibria in the conversion of metal-nitrate to metal- hydroxide and finally to metal-oxide, while in method-2 nanoparticle-metal-oxide remained intact during sol-gel-oil-drop and calcination steps. The alumina supported catalysts were dominated by gamma-alumina PXRD peaks in alumina catalysts while amorphous alumino-silicate phase was the bulk of hybrid alumina-silica catalysts. The presence of cobalt oxides (CoO, Co3O4) and iron oxides (FeO, Fe2O3) phases are confirmed in the catalysts prepared by method-1 and method-2. The PXRD analysis indicated weak peak intensities in catalysts with 5 wt. % total metal loading. PXRD pattern confirmed alloy formation in the bimetallic catalysts (CoFe2O4) on alumina support phase gamma-A12 O3. The surface area and pore diameter of hybrid alumina-silica granules (301 - 372 m2/g and 7.3 nm) showed better values than the alumina granules (251 - 256 m2/g and 6.5 nm). The support pore diameter of both types of granules is within the mesoporous range (1 - 50 nm). The morphology of all the catalysts is preserved upon metal loading and heat treatments. The surface characteristics of the sol-gel-oil-drop method prepared catalysts indicate there was no significant pore blockage of the support below 10 wt % total metal loading. The CO conversion of the FT catalysts was measured to screen catalytic active metals and determine the optimum temperatures of the FT reaction for the alumina catalysts. The alumina FT catalysts showed an optimum reaction temperature of 250 °C. Hydrocarbon production and CO conversion of alumina and hybrid alumina-silica FT catalysts were investigated. Among monometallic alumina catalysts, Co(5%) showed a higher CO conversion. The incorporation of Fe to Co increased CO conversion and hydrocarbon production. Increased Fe content in the bimetallic catalysts prepared by combined method-1&2, decreased CO conversion and hydrocarbon production, and increased CO 2 production. The bimetallic nano-Co(2.5%)nano-Fe(2.5%) prepared by method-2 alone showed higher CO conversion comparable to the Co(4%)nano-Fe(l %). Hybrid alumina-silica FT catalysts showed a higher CO conversion than the alumina FT catalysts due to better surface characteristics. The monometallic catalysts showed higher selectivity to C1-C4 hydrocarbon than bimetallic. The bimetallic alumina FT catalysts prepared by method-2 showed slightly higher C5+ selectivity compared to the higher Co catalysts prepared by combined method- I &2. The Ru promotion showed a significant effect on the CO conversion and 11 product distribution of the monometallic catalysts. There was no significant effect on the CO conversion on the (Co-Fe) bimetallic catalysts, but hydrocarbon production slightly increased when promoted by 0.5 wt.% Ru.

  4. Synthesis, characterization, and activity of Co/Fe alumina/silica supported Ft catalysts and the study of promoter effect of ruthenium

    NASA Astrophysics Data System (ADS)

    Esumike, Sunday Azubike

    The alumina and hybrid alumina-silica FT catalyst were prepared by one-step solgel/oil-drop methods using metal-nitrate-solutions (method-I), and nanoparticle-metaloxides (method-2). The nanoparticle-metal-oxides did not participate in solubility equilibria in contrast to metal nitrate in method-1 causing no metal ion seepage; therefore, method-2 yields higher XRF metal loading efficiency than method-1. The thermal analysis confirmed that the metal loading by method-1 and method-2 involved two different pathways. Method-1 involves solubility equilibria in the conversion of metal-nitrate to metal- hydroxide and finally to metal-oxide, while in method-2 nanoparticle-metal-oxide remained intact during sol-gel-oil-drop and calcination steps. The alumina supported catalysts were dominated by gamma-alumina PXRD peaks in alumina catalysts while amorphous alumino-silicate phase was the bulk of hybrid alumina-silica catalysts. The presence of cobalt oxides (CoO, Co3O4) and iron oxides (FeO, Fe2O3) phases are confirmed in the catalysts prepared by method-1 and method-2. The PXRD analysis indicated weak peak intensities in catalysts with 5 wt. % total metal loading. PXRD pattern confirmed alloy formation in the bimetallic catalysts (CoFe2O4) on alumina support phase gamma-A12 O3. The surface area and pore diameter of hybrid alumina-silica granules (301 - 372 m2/g and 7.3 nm) showed better values than the alumina granules (251 - 256 m2/g and 6.5 nm). The support pore diameter of both types of granules is within the mesoporous range (1 - 50 nm). The morphology of all the catalysts is preserved upon metal loading and heat treatments. The surface characteristics of the sol-gel-oil-drop method prepared catalysts indicate there was no significant pore blockage of the support below 10 wt % total metal loading. The CO conversion of the FT catalysts was measured to screen catalytic active metals and determine the optimum temperatures of the FT reaction for the alumina catalysts. The alumina FT catalysts showed an optimum reaction temperature of 250 °C. Hydrocarbon production and CO conversion of alumina and hybrid alumina-silica FT catalysts were investigated. Among monometallic alumina catalysts, Co(5%) showed a higher CO conversion. The incorporation of Fe to Co increased CO conversion and hydrocarbon production. Increased Fe content in the bimetallic catalysts prepared by combined method-1&2, decreased CO conversion and hydrocarbon production, and increased CO 2 production. The bimetallic nano-Co(2.5%)nano-Fe(2.5%) prepared by method-2 alone showed higher CO conversion comparable to the Co(4%)nano-Fe(l %). Hybrid alumina-silica FT catalysts showed a higher CO conversion than the alumina FT catalysts due to better surface characteristics. The monometallic catalysts showed higher selectivity to C1-C4 hydrocarbon than bimetallic. The bimetallic alumina FT catalysts prepared by method-2 showed slightly higher C5+ selectivity compared to the higher Co catalysts prepared by combined method- I &2. The Ru promotion showed a significant effect on the CO conversion and 11 product distribution of the monometallic catalysts. There was no significant effect on the CO conversion on the (Co-Fe) bimetallic catalysts, but hydrocarbon production slightly increased when promoted by 0.5 wt.% Ru.

  5. Hybrid zinc oxide/graphene electrodes for depleted heterojunction colloidal quantum-dot solar cells.

    PubMed

    Tavakoli, Mohammad Mahdi; Aashuri, Hossein; Simchi, Abdolreza; Fan, Zhiyong

    2015-10-07

    Recently, hybrid nanocomposites consisting of graphene/nanomaterial heterostructures have emerged as promising candidates for the fabrication of optoelectronic devices. In this work, we have employed a facile and in situ solution-based process to prepare zinc oxide/graphene quantum dots (ZnO/G QDs) in a hybrid structure. The prepared hybrid dots are composed of a ZnO core, with an average size of 5 nm, warped with graphene nanosheets. Spectroscopic studies show that the graphene shell quenches the photoluminescence intensity of the ZnO nanocrystals by about 72%, primarily due to charge transfer reactions and static quenching. A red shift in the absorption peak is also observed. Raman spectroscopy determines G-band splitting of the graphene shell into two separated sub-bands (G(+), G(-)) caused by the strain induced symmetry breaking. It is shown that the hybrid ZnO/G QDs can be used as a counter-electrode for heterojunction colloidal quantum-dot solar cells for efficient charge-carrier collection, as evidenced by the external quantum efficiency measurement. Under the solar simulated spectrum (AM 1.5G), we report enhanced power conversion efficiency (35%) with higher short current circuit (80%) for lead sulfide-based solar cells as compared to devices prepared by pristine ZnO nanocrystals.

  6. Enhanced performance of dye-sensitized solar cells with layered structure graphitic carbon nitride and reduced graphene oxide modified TiO2 photoanodes

    NASA Astrophysics Data System (ADS)

    Lv, Huiru; Hu, Haihua; Cui, Can; Lin, Ping; Wang, Peng; Wang, Hao; Xu, Lingbo; Pan, Jiaqi; Li, Chaorong

    2017-11-01

    TiO2/reduced graphene oxide (TiO2/rGO) composite has been widely exploited as the photoanode material for high efficient dye-sensitized solar cells (DSSCs). However, the power conversion efficiency (PCE) is limited due to the charge recombination between the rGO and electrolyte. In this paper, we incorporate 5.5 wt% layered structure graphitic carbon nitride (g-C3N4) and 0.25 wt% rGO into TiO2 nanoparticle (NP) film to form a triple-component TiO2/rGO/g-C3N4 (TGC) photoanode for DSSCs. The TGC photoanode significantly increased the dye absorption and thus to improve the light harvesting efficiency. Furthermore, the electrochemical impedance spectroscopy (EIS) analysis of the DSSCs based on TGC photoanode demonstrates that the incorporation of the rGO and g-C3N4 into TiO2 effectively accelerates the electron transfer and reduces the charge recombination. As a result, the DSSCs based on TGC film show PCE of 5.83%, enhanced by 50.1% compared with that of pure TiO2 photoanodes. This result strongly suggests a facile strategy to improve the photovoltaic performance of DSSCs.

  7. Advancements in Copper Nanowires: Synthesis, Purification, Assemblies, Surface Modification, and Applications.

    PubMed

    Zhao, Songfang; Han, Fei; Li, Jinhui; Meng, Xiangying; Huang, Wangping; Cao, Duxia; Zhang, Guoping; Sun, Rong; Wong, Ching-Ping

    2018-06-01

    Copper nanowires (CuNWs) are attracting a myriad of attention due to their preponderant electric conductivity, optoelectronic and mechanical properties, high electrocatalytic efficiency, and large abundance. Recently, great endeavors are undertaken to develop controllable and facile approaches to synthesize CuNWs with high dispersibility, oxidation resistance, and zero defects for future large-scale nano-enabled materials. Herein, this work provides a comprehensive review of current remarkable advancements in CuNWs. The Review starts with a thorough overview of recently developed synthetic strategies and growth mechanisms to achieve single-crystalline CuNWs and fivefold twinned CuNWs by the reduction of Cu(I) and Cu(II) ions, respectively. Following is a discussion of CuNW purification and multidimensional assemblies comprising films, aerogels, and arrays. Next, several effective approaches to protect CuNWs from oxidation are highlighted. The emerging applications of CuNWs in diverse fields are then focused on, with particular emphasis on optoelectronics, energy storage/conversion, catalysis, wearable electronics, and thermal management, followed by a brief comment on the current challenges and future research directions. The central theme of the Review is to provide an intimate correlation among the synthesis, structure, properties, and applications of CuNWs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Heterogeneous WS x/WO 3 thorn-bush nanofiber electrodes for sodium-ion batteries

    DOE PAGES

    Ryu, Won -Hee; Wilson, Hope; Sohn, Sungwoo; ...

    2016-01-25

    Heterogeneous electrode materials with hierarchical architectures promise to enable considerable improvement in future energy storage devices. In this study, we report on a tailored synthetic strategy used to create heterogeneous tungsten sulfide/oxide core–shell nanofiber materials with vertically and randomly aligned thorn-bush features, and we evaluate them as potential anode materials for high-performance Na-ion batteries. The WS x (2 ≤ x ≤ 3, amorphous WS 3 and crystalline WS 2) nanofiber is successfully prepared by electrospinning and subsequent calcination in a reducing atmosphere. To prevent capacity degradation of the WS x anodes originating from sulfur dissolution, a facile post-thermal treatment inmore » air is applied to form an oxide passivation surface. Interestingly, WO 3 thorn bundles are randomly grown on the nanofiber stem, resulting from the surface conversion. We elucidate the evolving morphological and structural features of the nanofibers during post-thermal treatment. The heterogeneous thorn-bush nanofiber electrodes deliver a high second discharge capacity of 791 mAh g –1 and improved cycle performance for 100 cycles compared to the pristine WS x nanofiber. Lastly, we show that this hierarchical design is effective in reducing sulfur dissolution, as shown by cycling analysis with counter Na electrodes.« less

  9. Citric acid induced promoted dispersion of Pt on the support and enhanced catalytic activities for a Pt-based catalyst

    NASA Astrophysics Data System (ADS)

    Cheng, Tianqiong; Wang, Jianli; Wang, Suning; Cui, Yajuan; Zhang, Hailong; Yan, Shuang; Yuan, Shandong; Chen, Yaoqiang

    2017-12-01

    Citric acid (CA), as the chelating agent, was introduced to obtain the enhanced Pt dispersion and catalytic activities for the Pt-based catalysts supported on oxygen-storage material. The role and content of CA were investigated systematically. It was found that the citric acid-assisted catalysts showed better Pt dispersion and smaller nanoparticle size of Pt. Thus, the catalyst had lower reduction temperature, preferable thermostability and possessed more oxidation state of Pt species under the oxidation atmosphere. The citric acid-induced fresh catalysts were excellent to convert CO and the corresponding aged ones exhibited higher activities for the elimination of all the target pollutants. Among the aged catalysts, P2-a (the mole ratio of Pt/CA is 2:1) presented the best performance. Particularly, compared with the reference sample (Pc-a), the light-off temperatures (T50) of NO, HC and CO for P2-a decreased by 39 °C, 42 °C and 72 °C, respectively, and the full-conversion temperatures (T90) of NO, HC and CO for P2-a decreased by 44 °C, 44 °C and 48 °C, respectively. Therefore, this work provides a facile and valid method to manufacture advanced catalysts for purification of the vehicle exhaust in the future.

  10. Photovoltaic performance and stability of fullerene/cerium oxide double electron transport layer superior to single one in p-i-n perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Xing, Zhou; Li, Shu-Hui; Wu, Bao-Shan; Wang, Xin; Wang, Lu-Yao; Wang, Tan; Liu, Hao-Ran; Zhang, Mei-Lin; Yun, Da-Qin; Deng, Lin-Long; Xie, Su-Yuan; Huang, Rong-Bin; Zheng, Lan-Sun

    2018-06-01

    Interface engineering that involves in the metal cathodes and the electron transport layers (ETLs) facilitates the simultaneous improvement of device performances and stability in perovskite solar cells (PSCs). Herein, low-temperature solution-processed cerium oxide (CeOx) films are prepared by a facile sol-gel method and employed as the interface layers between [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) and an Ag back contact to form PC61BM/CeOx double ETLs. The introduction of CeOx enables electron extraction to the Ag electrode and protects the underlying perovskite layer and thus improves the device performance and stability of the p-i-n PSCs. The p-i-n PSCs with double PC61BM/CeOx ETLs demonstrate a maximum power conversion efficiency (PCE) of 17.35%, which is superior to those of the devices with either PC61BM or CeOx single ETLs. Moreover, PC61BM/CeOx devices exhibit excellent stability in light soaking, which is mainly due to the chemically stable CeOx interlayer. The results indicate that CeOx is a promising interface modification layer for stable high-efficiency PSCs.

  11. Metal-Organic Framework Derived Porous Hollow Co3O4/N-C Polyhedron Composite with Excellent Energy Storage Capability.

    PubMed

    Kang, Wenpei; Zhang, Yu; Fan, Lili; Zhang, Liangliang; Dai, Fangna; Wang, Rongming; Sun, Daofeng

    2017-03-29

    Metal-organic frameworks (MOFs) derived transition metal oxides exhibit enhanced performance in energy conversion and storage. In this work, porous hollow Co 3 O 4 with N-doped carbon coating (Co 3 O 4 /N-C) polyhedrons have been prepared using cobalt-based MOFs as a sacrificial template. Assembled from tiny nanoparticles and N-doped carbon coating, Co 3 O 4 /N-C composite shortens the diffusion length of Li + /Na + ions and possesses an enhanced conductivity. And the porous and hollow structure is also beneficial for tolerating volume changes in the galvanostatic discharge/charge cycles as lithium/sodium battery anode materials. As a result, it can exhibit impressive cycling and rating performance. At 1000 mA g -1 , the specific capacities maintaine stable values of ∼620 mAh g -1 within 2000 cycles as anodes in lithium ion battery, while the specific capacity keeps at 229 mAh g -1 within 150 cycles as sodium ion battery anode. Our work shows comparable cycling performance in lithium ion battery but even better high-rate cycling stability as sodium ion battery anode. Herein, we provide a facile method to construct high electrochemical performance oxide/N-C composite electrode using new MOFs as sacrificial template.

  12. Soot oxidation and NO{sub x} reduction over BaAl{sub 2}O{sub 4} catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, He; Li, Yingjie; Shangguan, Wenfeng

    2009-11-15

    This study addresses soot oxidation and NO{sub x} reduction over a BaAl{sub 2}O{sub 4} catalyst. By XRD analysis, the catalyst was shown to be of spinel structure. Temperature Programmed Oxidation (TPO) and Constant Temperature Oxidation (CTO) at 673 K show that the presence of O{sub 2} decreases the ignition temperature of soot, and it enhances the conversion of NO{sub x} to N{sub 2} and N{sub 2}O. The kinetic features of soot oxidation in the TPO test are similar to that in the TG-DTA analysis. Analysis by Diffuse Reflectance Fourier Infrared Transform Spectroscopy (DRIFTS) indicates that the nitrates formed from NO{submore » x} adsorption and the C(O) intermediates from soot oxidation are the key precursors of the redox process between soot and NO{sub x} over surfaces of the BaAl{sub 2}O{sub 4} catalyst. Moreover, DRIFTS tests suggest that nitrates act as the principal oxidants for C(O) oxidation, through which nitrates are reduced to N{sub 2} and N{sub 2}O. The O{sub 2} in the gas mixture presents a positive effect on the conversion of NO{sub x} to N{sub 2} and N{sub 2}O by promoting the oxidation of nitrites into nitrates species. (author)« less

  13. Radioactive waste material disposal

    DOEpatents

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-10-24

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

  14. Radioactive waste material disposal

    DOEpatents

    Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

    1995-01-01

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

  15. Cocatalysts in Semiconductor-based Photocatalytic CO2 Reduction: Achievements, Challenges, and Opportunities.

    PubMed

    Ran, Jingrun; Jaroniec, Mietek; Qiao, Shi-Zhang

    2018-02-01

    Ever-increasing fossil-fuel combustion along with massive CO 2 emissions has aroused a global energy crisis and climate change. Photocatalytic CO 2 reduction represents a promising strategy for clean, cost-effective, and environmentally friendly conversion of CO 2 into hydrocarbon fuels by utilizing solar energy. This strategy combines the reductive half-reaction of CO 2 conversion with an oxidative half reaction, e.g., H 2 O oxidation, to create a carbon-neutral cycle, presenting a viable solution to global energy and environmental problems. There are three pivotal processes in photocatalytic CO 2 conversion: (i) solar-light absorption, (ii) charge separation/migration, and (iii) catalytic CO 2 reduction and H 2 O oxidation. While significant progress is made in optimizing the first two processes, much less research is conducted toward enhancing the efficiency of the third step, which requires the presence of cocatalysts. In general, cocatalysts play four important roles: (i) boosting charge separation/transfer, (ii) improving the activity and selectivity of CO 2 reduction, (iii) enhancing the stability of photocatalysts, and (iv) suppressing side or back reactions. Herein, for the first time, all the developed CO 2 -reduction cocatalysts for semiconductor-based photocatalytic CO 2 conversion are summarized, and their functions and mechanisms are discussed. Finally, perspectives in this emerging area are provided. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Electrochemical enhancement of nitric oxide removal from simulated lean-burn engine exhaust via solid oxide fuel cells.

    PubMed

    Huang, Ta-Jen; Wu, Chung-Ying; Lin, Yu-Hsien

    2011-07-01

    A solid oxide fuel cell (SOFC) unit is constructed with Ni-YSZ as the anode, YSZ as the electrolyte, and La(0.6)Sr(0.4)CoO(3)-Ce(0.9)Gd(0.1)O(1.95) as the cathode. The SOFC operation is performed at 600 °C with a cathode gas simulating the lean-burn engine exhaust and at various fixed voltage, at open-circuit voltage, and with an inert gas flowing over the anode side, respectively. Electrochemical enhancement of NO decomposition occurs when an operating voltage is generated; higher O(2) concentration leads to higher enhancement. Smaller NO concentration results in larger NO conversion. Higher operating voltage and higher O(2) concentration can lead to both higher NO conversion and lower fuel consumption. The molar rate of the consumption of the anode fuel can be very much smaller than that of NO to N(2) conversion. This makes the anode fuel consumed in the SOFC-DeNO(x) process to be much less than the equivalent amount of ammonia consumed in the urea-based selective catalytic reduction process. Additionally, the NO conversion increases with the addition of propylene and SO(2) into the cathode gas. These are beneficial for the application of the SOFC-DeNO(x) technology on treating diesel and other lean-burn engine exhausts.

  17. Life sciences space station planning document: A reference payload for the exobiology research facilities

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The Cosmic Dust Collection and Gas Grain Simulation Facilities represent collaborative efforts between the Life Sciences and Solar System Exploration Divisions designed to strengthen a natural exobiology/Planetary Sciences connection. The Cosmic Dust Collection Facility is a Planetary Science facility, with Exobiology a primary user. Conversely, the Gas Grain Facility is an exobiology facility, with Planetary Science a primary user. Requirements for the construction and operation of the two facilities, contained herein, were developed through joint workshops between the two disciplines, as were representative experiments comprising the reference payloads. In the case of the Gas Grain Simulation Facility, the astrophysics Division is an additional potential user, having participated in the workshop to select experiments and define requirements.

  18. [Oxidation behavior and kinetics of representative VOCs emitted from petrochemical industry over CuCeOx composite oxides].

    PubMed

    Chen, Chang-Wei; Yu, Yan-Ke; Chen, Jin-Sheng; He, Chi

    2013-12-01

    CuCeOx composite catalysts were synthesized via coprecipitation (COP-CuCeO,) and incipient impregnation (IMP-CuCeOx) methods, respectively. The physicochemical properties of the samples were characterized by XRD, low-temperature N2 sorption, H2-TPR and O2-TPD. The influences of reactant composition and concentration, reaction space velocity, O2 content, H2O concentration, and catalyst type on the oxidation behaviors of benzene, toluene, and n-hexane emitted from petrochemical industry were systematically investigated. In addition, the related kinetic parameters were model fitted. Compared with IMP-CuCeOx, COP-CuCeOx had well-dispersed active phase, better low-temperature reducibility, and more active surface oxygen species. The increase of reactant concentration was unfavorable for toluene oxidation, while the opposite phenomenon could be observed in n-hexane oxidation. The inlet concentration of benzene was irrelevant to its conversion under high oxidation rate. The introduction of benzene obviously inhibited the oxidation of toluene and n-hexane, while the presence of toluene had a positive effect on beuzene conversion. The presence of n-hexane could promote the oxidation of toluene, while toluene had a negative influence on e-hexane oxidation. Both low space velocity and high oxygen concentration were beneficial for the oxidation process, and the variation of oxygen content had negligible effect on n-hexane and henzene oxidation. The presence of H2O noticeably inhibited the oxidation of toluene, while significantly accelerated the oxidation procedure of henzene and n-hexane. COP-CuCeOx had superior catalytic performance for toluene and benzene oxidation, while IMP-CuCeOx showed higher n-hexane oxidation activity under dry condition. The oxidation behaviors under different conditions could be well fitted and predicted by the pseudo first-order kinetic model.

  19. An analytical method for 14C in environmental water based on a wet-oxidation process.

    PubMed

    Huang, Yan-Jun; Guo, Gui-Yin; Wu, Lian-Sheng; Zhang, Bing; Chen, Chao-Feng; Zhang, Hai-Ying; Qin, Hong-Juan; Shang-Guan, Zhi-Hong

    2015-04-01

    An analytical method for (14)C in environmental water based on a wet-oxidation process was developed. The method can be used to determine the activity concentrations of organic and inorganic (14)C in environmental water, or total (14)C, including in drinking water, surface water, rainwater and seawater. The wet-oxidation of the organic component allows the conversion of organic carbon to an inorganic form, and the extraction of the inorganic (14)C can be achieved by acidification and nitrogen purging. Environmental water with a volume of 20 L can be used for the wet-oxidation and extraction, and a detection limit of about 0.02 Bq/g(C) can be achieved for water with carbon content above 15 mg(C)/L, obviously lower than the natural level of (14)C in the environment. The collected carbon is sufficient for measurement with a low level liquid scintillation counter (LSC) for typical samples. Extraction or recovery experiments for inorganic carbon and organic carbon from typical materials, including analytical reagents of organic benzoquinone, sucrose, glutamic acid, nicotinic acid, humic acid, ethane diol, et cetera., were conducted with excellent results based on measurement on a total organic carbon analyzer and LSC. The recovery rate for inorganic carbon ranged tween 98.7%-99.0% with a mean of 98.9(± 0.1)%, for organic carbon recovery ranged between 93.8% and 100.0% with a mean of 97.1(± 2.6)%. Verification and an uncertainty budget of the method are also presented for a representative environmental water. The method is appropriate for (14)C analysis in environmental water, and can be applied also to the analysis of liquid effluent from nuclear facilities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Performance of ultraviolet photocatalytic oxidation for indoor air cleaning applications.

    PubMed

    Hodgson, A T; Destaillats, H; Sullivan, D P; Fisk, W J

    2007-08-01

    Ultraviolet photocatalytic oxidation (UVPCO) systems for removal of volatile organic compounds (VOCs) from air are being considered for use in office buildings. Here, we report an experimental evaluation of a UVPCO device with tungsten oxide modified titanium dioxide (TiO2) as the photocatalyst. The device was challenged with complex VOC mixtures. One mixture contained 27 VOCs characteristic of office buildings and another comprised 10 VOCs emitted by cleaning products, in both cases at realistic concentrations (low ppb range). VOC conversion efficiencies varied widely, usually exceeded 20%, and were as high as approximately 80% at about 0.03 s residence time. Conversion efficiency generally diminished with increased airflow rate, and followed the order: alcohols and glycol ethers > aldehydes, ketones, and terpene hydrocarbons > aromatic and alkane hydrocarbons > halogenated aliphatic hydrocarbons. Conversion efficiencies correlated with the Henry's law constant more closely than with other physicochemical parameters. An empirical model based on the Henry's law constant and the gas-phase reaction rate with hydroxyl radical provided reasonable estimates of pseudo-first order photocatalytic reaction rates. Formaldehyde, acetaldehyde, acetone, formic acid and acetic acid were produced by the device due to incomplete mineralization of common VOCs. Formaldehyde outlet/inlet concentration ratios were in the range 1.9-7.2. Implementation of air cleaning technologies for both VOCs and particles in office buildings may improve indoor air quality, or enable indoor air quality levels to be maintained with reduced outdoor air supply and concomitant energy savings. One promising air cleaning technology is ultraviolet photocatalytic oxidation (UVPCO) air cleaning. For the prototype device evaluated here with realistic mixtures of VOCs, conversion efficiencies typically exceeded the minimum required to counteract predicted VOC concentration increases from a 50% reduction in ventilation. However, the device resulted in the net generation of formaldehyde and acetaldehyde from the partial oxidation of ubiquitous VOCs. Further development of the technology is needed to eliminate these hazardous air pollutants before such a UVPCO device can be deployed in buildings.

  1. Skeletal Muscle-Specific Overexpression of PGC-1α Induces Fiber-Type Conversion through Enhanced Mitochondrial Respiration and Fatty Acid Oxidation in Mice and Pigs.

    PubMed

    Zhang, Lin; Zhou, Ying; Wu, Wangjun; Hou, Liming; Chen, Hongxing; Zuo, Bo; Xiong, Yuanzhu; Yang, Jinzeng

    2017-01-01

    Individual skeletal muscles in the animal body are heterogeneous, as each is comprised of different fiber types. Type I muscle fibers are rich with mitochondria, and have high oxidative metabolisms while type IIB fibers have few mitochondria and high glycolytic metabolic capacity. Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a transcriptional co-activator that regulates mitochondrial biogenesis and respiratory function, is implicated in muscle fiber-type switching. Over-expression of PGC-1α in transgenic mice increased the proportion of red/oxidative type I fiber. During pig muscle growth, an increased number of type I fibers can give meat more red color. To explore the roles of PGC-1α in regulation of muscle fiber type conversion, we generated skeletal muscle-specific PGC-1α transgenic mice and pig. Ectopic over-expression of PGC-1α was detected in both fast and slow muscle fibers. The transgenic animals displayed a remarkable amount of red/oxidative muscle fibers in major skeletal muscle tissues. Skeletal muscles from transgenic mice and pigs have increased expression levels of oxidative fiber markers such as MHC1, MHC2x, myoglobin and Tnni1, and decreased expressions of glycolytic fiber genes (MHC2a, MHC2b, CASQ-1 and Tnni2). The genes responsible for the TCA cycle and oxidative phosphorylation, cytochrome coxidase 2 and 4, and citrate synthase were also increased in the transgenic mice and pigs. These results suggested that transgenic over-expressed PGC-1α significantly increased muscle mitochondrial biogenesis, resulting in qualitative changes from glycolytic to oxidative energy generation. The transgenic animals also had elevated levels of PDK4 and PPARγ proteins in muscle tissue, which can lead to increased glycogen deposition and fatty acid oxidation. Therefore, the results support a significant role of PGC-1α in conversion of fast glycolytic fibers to slow and oxidative fiber through enhanced mitochondrial respiration and fatty acid oxidation, and transgenic over-expression of PGC-1α in skeletal muscle leads to more red meat production in pigs.

  2. Arginine, citrulline and nitric oxide metabolism in sepsis

    USDA-ARS?s Scientific Manuscript database

    Arginine has vasodilatory effects, via its conversion by nitric oxide (NO) synthase into NO, and immunomodulatory actions that play important roles in sepsis. Protein breakdown affects arginine availability, and the release of asymmetric dimethylarginine, an inhibitor of NO synthase, may therefore a...

  3. Oxidation of Cyclohexene to "trans"-1,2-Cyclohexanediol Promoted by "p"-Toluenesulfonic Acid without Organic Solvents

    ERIC Educational Resources Information Center

    Rosatella, Andreia A.; Afonso, Carlos A. M.; Branco, Lus C.

    2011-01-01

    This experiment describes a method for cyclohexene oxidation to "trans"-1,2-cyclohexanediol using "p"-toluenesulfonic acid ("p"-TsOH) as promoter and hydrogen peroxide as oxidant in a biphasic system. This method allows conversions up to 97.9% (monitored by [superscript 1]H NMR). "trans"-1,2-Cyclohexanediol was not easily separated from the…

  4. MPF: A portable message passing facility for shared memory multiprocessors

    NASA Technical Reports Server (NTRS)

    Malony, Allen D.; Reed, Daniel A.; Mcguire, Patrick J.

    1987-01-01

    The design, implementation, and performance evaluation of a message passing facility (MPF) for shared memory multiprocessors are presented. The MPF is based on a message passing model conceptually similar to conversations. Participants (parallel processors) can enter or leave a conversation at any time. The message passing primitives for this model are implemented as a portable library of C function calls. The MPF is currently operational on a Sequent Balance 21000, and several parallel applications were developed and tested. Several simple benchmark programs are presented to establish interprocess communication performance for common patterns of interprocess communication. Finally, performance figures are presented for two parallel applications, linear systems solution, and iterative solution of partial differential equations.

  5. A Finite Rate Chemical Analysis of Nitric Oxide Flow Contamination Effects on Scramjet Performance

    NASA Technical Reports Server (NTRS)

    Cabell, Karen F.; Rock, Kenneth E.

    2003-01-01

    The level of nitric oxide contamination in the test gas of the Langley Research Center Arc-Heated Scramjet Test Facility and the effect of the contamination on scramjet test engine performance were investigated analytically. A finite rate chemical analysis was performed to determine the levels of nitric oxide produced in the facility at conditions corresponding to Mach 6 to 8 flight simulations. Results indicate that nitric oxide levels range from one to three mole percent, corroborating previously obtained measurements. A three-stream combustor code with finite rate chemistry was used to investigate the effects of nitric oxide on scramjet performance. Results indicate that nitric oxide in the test gas causes a small increase in heat release and thrust performance for the test conditions investigated. However, a rate constant uncertainty analysis suggests that the effect of nitric oxide ranges from no net effect, to an increase of about 10 percent in thrust performance.

  6. Nitride Fuel Development Using Cryo-process Technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Brien, Brandi M; Windes, William E

    A new cryo-process technique has been developed for the fabrication of advanced fuel for nuclear systems. The process uses a new cryo-processing technique whereby small, porous microspheres (<2000 µm) are formed from sub-micron oxide powder. A simple aqueous particle slurry of oxide powder is pumped through a microsphere generator consisting of a vibrating needle with controlled amplitude and frequency. As the water-based droplets are formed and pass through the microsphere generator they are frozen in a bath of liquid nitrogen and promptly vacuum freeze-dried to remove the water. The resulting porous microspheres consist of half micron sized oxide particles heldmore » together by electrostatic forces and mechanical interlocking of the particles. Oxide powder microspheres ranging from 750 µm to 2000 µm are then converted into a nitride form using a high temperature fluidized particle bed. Carbon black can be added to the oxide powder before microsphere formation to augment the carbothermic reaction during conversion to a nitride. Also, the addition of ethyl alcohol to the aqueous slurry reduces the surface tension energy of the droplets resulting in even smaller droplets forming in the microsphere generator. Initial results from this new process indicate a lower impurity contamination in the final nitrides due to the single feed stream of particles, material handling and conversion are greatly simplified, a minimum of waste and personnel exposure are anticipated, and finally the conversion kinetics may be greatly increased because of the small oxide powder size (sub-micron) forming the porous microsphere. Thus far the fabrication process has been successful in demonstrating all of these improvements with surrogate ZrO2 powder. Further tests will be conducted in the future using the technique on UO2 powders.« less

  7. Early changes in fiber profile and capillary density in long-term stimulated muscles.

    PubMed

    Hudlická, O; Dodd, L; Renkin, E M; Gray, S D

    1982-10-01

    Predominantly fast skeletal muscles of rabbits [tibialis anterior (TA), extensor digitorum longus (EDL)] were stimulated at a frequency naturally occurring in nerves to slow muscles (10 Hz continuously) for 8 h/day for 2--4 days. Such stimulation is known to convert all glycolytic fibers to oxidative and to increase capillary density. Our aim was to study early stages of conversion to investigate the factors responsible for the changes. Staining of quick-frozen sections for myosin ATPase, succinic dehydrogenase, and alkaline phosphatase was used to study the distribution of different fiber types and to measure fiber cross-sectional areas, capillaries per square millimeter, and capillary-to-fiber ratios in each fiber category. TA but not EDL showed conversion of fast glycolytic to fast oxidative fibers after 2 days, more after 4 days of stimulation. In both muscles, the largest fast glycolytic fibers were diminished in number after stimulation. There was significant increase in total capillaries per square millimeter after 4 days and some increase after 2 days of stimulation. The increase in capillaries per square millimeter exceeded the increase in the number of fibers per square millimeter, and since there was no change in mean fiber area, the increase is attributed to capillary growth. In EDL, there was an increase in the number of capillaries supplying both fast glycolytic and fast oxidative fibers, suggesting that capillary growth precedes fiber type conversion. In TA, the number of capillaries supplying fast oxidative fibers was increased but that to fast glycolytic fibers, was not. This is consistent with capillary growth simultaneous with or following fiber conversion. In both TA and EDL the number of capillaries perfused after contraction was higher in stimulated muscles, suggesting that increased capillary flow contributed to capillary growth.

  8. Transient studies of low temperature catalysts for methane conversion. Final report, [September 1992--March 1996

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wolf, E.E.

    1996-09-30

    The objective of this project is to use transient techniques to study gas surface interactions during the oxidative conversion of methane. Two groups of catalysts were studied: a double oxide of vanadium and phosphate or VPO, and double oxides of Ni, Co and Rh and lanthana. The objective of the studies involving the VPO catalyst was to understand gas-surface interactions leading to the formation of formaldehyde. In the second group of catalysts, involving metallo-oxides, the main objective was to study the gas-surface interactions that determine the selectivity to C{sub 2} hydrocarbons or synthesis gas. Transient techniques were used to studymore » the methane-surface interactions and the role of lattice oxygen. The selection of the double oxides was made on the hypothesis that the metal oxide would provide an increase interaction with methane whereas the phosphate or lanthanide would provide the sites for oxygen adsorption. The hypothesis behind this selection of catalysts was that increasing the methane interaction with the catalysts would lower the reaction temperature and thus increase the selectivity to the desired products over the total oxidation reaction. In both groups of catalysts the role of Li as a modifier of the selectivity was also studied in detail.« less

  9. The Homestake Interim Laboratory and Homestake DUSEL

    NASA Astrophysics Data System (ADS)

    Lesko, Kevin T.

    2011-12-01

    The former Homestake gold mine in Lead South Dakota is proposed for the National Science Foundation's Deep Underground Science and Engineering Laboratory (DUSEL). The gold mine provides expedient access to depths in excess of 8000 feet below the surface (>7000 mwe). Homestake's long history of promoting scientific endeavours includes the Davis Solar Neutrino Experiment, a chlorine-based experiment that was hosted at the 4850 Level for more than 30 years. As DUSEL, Homestake would be uncompromised by competition with mining interests or other shared uses. The facility's 600-km of drifts would be available for conversion for scientific and educational uses. The State of South Dakota, under Governor Rounds' leadership, has demonstrated exceptionally strong support for Homestake and the creation of DUSEL. The State has provided funding totalling $46M for the preservation of the site for DUSEL and for the conversion and operation of the Homestake Interim Laboratory. Motivated by the strong educational and outreach potential of Homestake, the State contracted a Conversion Plan by world-recognized mine-engineering contractor to define the process of rehabilitating the facility, establishing the appropriate safety program, and regaining access to the facility. The State of South Dakota has established the South Dakota Science and Technology Authority to oversee the transfer of the Homestake property to the State and the rehabilitation and preservation of the facility. The Homestake Scientific Collaboration and the State of South Dakota's Science and Technology Authority has called for Letters of Interest from scientific, educational and engineering collaborations and institutions that are interested in hosting experiments and uses in the Homestake Interim Facility in advance of the NSF's DUSEL, to define experiments starting as early as 2007. The Homestake Program Advisory Committee has reviewed these Letters and their initial report has been released. Options for developing the Homestake Interim Laboratory and evolving this facility into DUSEL are presented.

  10. "A bridge over troubled gaps": up-conversion driven photocatalysis for hydrogen generation and pollutant degradation by near-infrared excitation.

    PubMed

    Acosta-Mora, P; Domen, K; Hisatomi, T; Lyu, H; Méndez-Ramos, J; Ruiz-Morales, J C; Khaidukov, N M

    2018-02-15

    Spectral up-conversion (UC) has been attracting growing interest for the effective harvesting of the near-infrared (NIR) part of sunlight for photocatalytic hydrogen production and environmental purification. We present evidence of NIR-to-UV-VIS photon conversion for degradation of organic dyes and hydrogen and oxygen evolution via water-splitting by TiO 2 and Rh-Cr oxide-loaded SrTiO 3 :Al photocatalysts, respectively.

  11. Looking Southwest to Dry and Wet Exterior Scrubbers at Rear ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest to Dry and Wet Exterior Scrubbers at Rear of Oxide Building - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  12. 77 FR 70193 - Shaw Areva MOX Services (Mixed Oxide Fuel Fabrication Facility); Notice of Atomic Safety and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-23

    ... MOX Services (Mixed Oxide Fuel Fabrication Facility); Notice of Atomic Safety and Licensing Board Reconstitution Pursuant to 10 CFR 2.313(c) and 2.321(b), the Atomic Safety and Licensing Board (Board) in the... Rockville, Maryland this 16th day of November 2012. E. Roy Hawkens, Chief Administrative Judge, Atomic...

  13. Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim, E-mail: msab@iacs.res.in

    2014-07-01

    We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodine–triiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup −1}) and narrow pore size distributions (5.1–5.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dyemore » loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 μm in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup −2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: • Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. • Mesoporous ZnO materials have high BET surface areas and void space. • ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). • Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.« less

  14. Converting Y(OH){sub 3} nanofiber bundles to YVO{sub 4} polyhedrons for photodegradation of dye contaminants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Li; School of Chemical Engineering and Materials Engineering, Huainan Normal University, Huainan 232038; Zou, Lei

    2015-08-15

    Highlights: • YVO{sub 4} polyhedrons were prepared from Y(OH){sub 3} nanofiber bundles through a hydrothermal conversion process. • In contrast to the bulk oxide, the photocatalytic performance of the polyhedrons was much improved. • The main active species involved in photocatalytic oxidative reaction were also investigated. - Abstract: This paper reports a hydrothermal conversion process of rare earth microstructures, Y(OH){sub 3} nanofiber bundles, into YVO{sub 4} polyhedrons, together with the investigation on the related photocatalytic properties. The as-synthesized samples were characterized by a variety of techniques, including XRD, SEM, TEM and UV–vis diffuse reflectance spectroscopy. The photocatalytic activities of YVO{submore » 4} polyhedrons were comparatively evaluated by the photodegradation of Rhodamine B and methylene blue. In contrast to the bulk oxide, the photocatalytic performance of the polyhedrons was much improved. The mechanism and the main active species involved in photocatalytic oxidative reaction were also investigated through the carriers trapping experiments.« less

  15. Lead paste recycling based on conversion into battery grade oxides. Electrochemical tests and industrial production of new batteries

    NASA Astrophysics Data System (ADS)

    Fusillo, G.; Rosestolato, D.; Scura, F.; Cattarin, S.; Mattarozzi, L.; Guerriero, P.; Gambirasi, A.; Brianese, N.; Staiti, P.; Guerriero, R.; La Sala, G.

    2018-03-01

    We present the preparation and characterization of pure lead monoxide obtained through recycling of the lead paste recovered from exhausted lead acid batteries. The recycling is based on a hydrometallurgical procedure reported in a STC Patent, that includes simple chemical operations (desulphurisation, leaching, precipitation, filtration) and a final thermal conversion. Materials obtained by treatment at 600 °C consist predominantly of β-PbO. The electrochemical behaviour of Positive Active Mass (PAM) prepared from different materials (or mixtures) is then investigated and compared. An optimized oxide material, obtained by prolonged (8 h) thermal treatment at 600 °C, consists of pure β-PbO and appears suitable for preparation of battery elements, alone or in mixture with a small fraction (10%-30%) of traditional industrial leady oxide. The resulting battery performances are similar to those obtained from pure leady oxide. In comparison with traditional recycling processes, the proposed method guarantees lower energy consumption, limited environmental impact and reduced operating risk for industry workers.

  16. Controlled Embedding of Metal Oxide Nanoparticles in ZSM-5 Zeolites through Preencapsulation and Timed Release.

    PubMed

    Lai, Yungchieh; Rutigliano, Michael N; Veser, Götz

    2015-09-29

    We report a straightforward and transferrable synthesis strategy to encapsulate metal oxide nanoparticles (NPs) in mesoporous ZSM-5 via the encapsulation of NPs into silica followed by conversion of the NP@silica precursor to NP@ZSM-5. The systematic bottom-up approach allows for straightforward, precise control of both the metal weight loading and size of the embedded NP and yields uniform NP@ZSM-5 microspheres composed of stacked ZSM-5 nanorods with substantial mesoporosity. Key to the synthesis is the timed release of the embedded NPs during dissolution of the silica matrix in the hydrothermal conversion step, which finely balances the rate of NP release with the rate of SiO2 dissolution and the subsequent nucleation of aluminosilicate. The synthesis approach is demonstrated for Zn, Fe, and Ni oxide encapsulation in ZSM-5 but can be expected to be broadly transferrable for the encapsulation of metal and metal oxide nanoparticles into other zeolite structures.

  17. Carbon-Coated Honeycomb Ni-Mn-Co-O Inverse Opal: A High Capacity Ternary Transition Metal Oxide Anode for Li-ion Batteries

    PubMed Central

    McNulty, David; Geaney, Hugh; O’Dwyer, Colm

    2017-01-01

    We present the formation of a carbon-coated honeycomb ternary Ni-Mn-Co-O inverse opal as a conversion mode anode material for Li-ion battery applications. In order to obtain high capacity via conversion mode reactions, a single phase crystalline honeycombed IO structure of Ni-Mn-Co-O material was first formed. This Ni-Mn-Co-O IO converts via reversible redox reactions and Li2O formation to a 3D structured matrix assembly of nanoparticles of three (MnO, CoO and NiO) oxides, that facilitates efficient reactions with Li. A carbon coating maintains the structure without clogging the open-worked IO pore morphology for electrolyte penetration and mass transport of products during cycling. The highly porous IO was compared in a Li-ion half-cell to nanoparticles of the same material and showed significant improvement in specific capacity and capacity retention. Further optimization of the system was investigated by incorporating a vinylene carbonate additive into the electrolyte solution which boosted performance, offering promising high-rate performance and good capacity retention over extended cycling. The analysis confirms the possibility of creating a ternary transition metal oxide material with binder free accessible open-worked structure to allow three conversion mode oxides to efficiently cycle as an anode material for Li-ion battery applications. PMID:28186183

  18. Effect of substrate availability on nitrous oxide production by deammonification processes under anoxic conditions.

    PubMed

    Schneider, Yvonne; Beier, Maike; Rosenwinkel, Karl-Heinz

    2012-05-01

    Due to its high global warming potential, nitrous oxide (N(2)O) emissions from wastewater treatment processes have recently received a high degree of attention. Nevertheless, there is still a lack of information regarding the microbiological processes leading to N(2)O production. In this study, two lab-scale sequencing batch reactors were operated with deammonification biomass to investigate the role of denitrification and the influence of substrate availability regarding N(2)O formation during the anoxic phase of deammonification. Three different operational phases were established: within the first phase conversion by anammox was favoured and after a transition phase, denitrification activity was promoted. Low nitrous oxide production was observed during stable operation aiming for anammox conversion. Pulsed inflow of the wastewater containing ammonium (NH(4)(+)) and nitrite (NO(2)(-)) led to increased N(2)O production rates. Within the period of denitrification as dominating nitrogen conversion process, the nitrous oxide concentration level was higher during continuous inflow conditions, but the reaction to pulsed inflow was less pronounced. The results indicated that denitrification was responsible for N(2)O formation from the deammonification biomass. Operational settings to achieve suppression of denitrification processes to a large extend were deducted from the results of the experiments. © 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  19. Arsenic (+3 Oxidation State) Methyltransferase and the Methylation of Arsenicals

    PubMed Central

    Thomas, David J.; Li, Jiaxin; Waters, Stephen B.; Xing, Weibing; Adair, Blakely M.; Drobna, Zuzana; Devesa, Vicenta; Styblo, Miroslav

    2008-01-01

    Metabolic conversion of inorganic arsenic into methylated products is a multistep process that yields mono-, di-, and trimethylated arsenicals. In recent years, it has become apparent that formation of methylated metabolites of inorganic arsenic is not necessarily a detoxification process. Intermediates and products formed in this pathway may be more reactive and toxic than inorganic arsenic. Like all metabolic pathways, understanding the pathway for arsenic methylation involves identification of each individual step in the process and the characterization of the molecules which participate in each step. Among several arsenic methyltransferases that have been identified, arsenic (+3 oxidation state) methyltransferase is the one best characterized at the genetic and functional levels. This review focuses on phylogenetic relationships in the deuterostomal lineage for this enzyme and on the relation between genotype for arsenic (+3 oxidation state) methyltransferase and phenotype for conversion of inorganic arsenic to methylated metabolites. Two conceptual models for function of arsenic (+3 oxidation state) methyltransferase which posit different roles for cellular reductants in the conversion of inorganic arsenic to methylated metabolites are compared. Although each model accurately represents some aspects of enzyme’s role in the pathway for arsenic methylation, neither model is a fully satisfactory representation of all the steps in this metabolic pathway. Additional information on the structure and function of the enzyme will be needed to develop a more comprehensive model for this pathway. PMID:17202581

  20. Carbon-Coated Honeycomb Ni-Mn-Co-O Inverse Opal: A High Capacity Ternary Transition Metal Oxide Anode for Li-ion Batteries.

    PubMed

    McNulty, David; Geaney, Hugh; O'Dwyer, Colm

    2017-02-10

    We present the formation of a carbon-coated honeycomb ternary Ni-Mn-Co-O inverse opal as a conversion mode anode material for Li-ion battery applications. In order to obtain high capacity via conversion mode reactions, a single phase crystalline honeycombed IO structure of Ni-Mn-Co-O material was first formed. This Ni-Mn-Co-O IO converts via reversible redox reactions and Li 2 O formation to a 3D structured matrix assembly of nanoparticles of three (MnO, CoO and NiO) oxides, that facilitates efficient reactions with Li. A carbon coating maintains the structure without clogging the open-worked IO pore morphology for electrolyte penetration and mass transport of products during cycling. The highly porous IO was compared in a Li-ion half-cell to nanoparticles of the same material and showed significant improvement in specific capacity and capacity retention. Further optimization of the system was investigated by incorporating a vinylene carbonate additive into the electrolyte solution which boosted performance, offering promising high-rate performance and good capacity retention over extended cycling. The analysis confirms the possibility of creating a ternary transition metal oxide material with binder free accessible open-worked structure to allow three conversion mode oxides to efficiently cycle as an anode material for Li-ion battery applications.

  1. Transition metal sulfide loaded catalyst

    DOEpatents

    Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

    1994-04-26

    A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  2. Effect of the chloride ion as a hole scavenger on the photocatalytic conversion of CO2 in an aqueous solution over Ni-Al layered double hydroxides.

    PubMed

    Iguchi, Shoji; Teramura, Kentaro; Hosokawa, Saburo; Tanaka, Tsunehiro

    2015-07-21

    The photocatalytic conversion of CO2 into useful chemical compounds in water without using organic sacrificial reagents is a promising method to overcome environmental and energy problems. Various synthesized layered double hydroxides (LDHs) are capable of reducing CO2 to CO in an aqueous solution under UV light irradiation. However, it is difficult to oxidize H2O to O2 in a photocatalytic system using LDHs as photocatalysts. In this study, we investigated the photocatalytic conversion of CO2 using a Ni-Al LDH in an aqueous solution of NaCl. Hypochlorous acid (HClO) was produced as an oxidation product of Cl(-) with the formation of reduction products such as CO and H2 under photoirradiation. We propose the inclusion of Cl(-) in the reaction solution to be one of the most promising ways for obtaining a hole scavenger, an approach that would enable the construction of an artificial photosynthesis system for the conversion of CO2.

  3. CuO/CeO2 catalysts for glycerol selective conversion to lactic acid.

    PubMed

    Palacio, Ruben; Torres, Sebastian; Royer, Sébastien; Mamede, Anne Sophie; López, Diana; Hernández, Diana

    2018-03-26

    Ceria supported copper oxide catalysts were produced by a deposition-precipitation method, at a high copper loading (up to >25 wt%). These materials demonstrated excellent properties for glycerol selective conversion to lactic acid, with a conversion reaching up to 87% with a selectivity to lactic acid of 74% (8 h reaction, 220 °C, under N2 pressure). These catalysts also exhibited high stability upon 5 successive reaction cycles. The formation of a crystalline CuO phase was demonstrated in the nanocomposites at a high Cu loading, with elongated shaped particles formed on the cerium oxide surface. Such particles were however, not observed at low Cu loadings. XPS analysis revealed that Cu(ii) was the main Cu species on the fresh catalyst, and that this species was reduced to Cu(i) during the reaction. Complementary characterization over the spent catalyst clearly showed the morphological modifications of the CuO phase, however, did not impact significantly either glycerol conversion or selectivity to lactic acid upon recycling. For instance, apparently, the catalytic activity of CuO largely depends on the Cu(ii) species.

  4. Conversion of Methane to Methanol and Ethanol over Nickel Oxide on Ceria-Zirconia Catalysts in a Single Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Okolie, Chukwuemeka; Belhseine, Yasmeen F.; Lyu, Yimeng

    Here, the conversion of methane into alcohols under moderate reaction conditions is a promising technology for converting stranded methane reserves into liquids that can be transported in pipelines and upgraded to value-added chemicals. We demonstrate that a catalyst consisting of small nickel oxide clusters supported on ceria-zirconia (NiO/CZ) can convert methane to methanol and ethanol in a single, steady-state process at 723 K using O 2 as an abundantly available oxidant. The presence of steam is required to obtain alcohols rather than CO 2 as the product of catalytic combustion. The unusual activity of this catalyst is attributed to themore » synergy between the small Lewis acidic NiO clusters and the redox-active CZ support, which also stabilizes the small NiO clusters.« less

  5. Modulation of strain, resistance, and capacitance of tantalum oxide film by converse piezoelectric effect

    NASA Astrophysics Data System (ADS)

    Jia, Yanmin; Tian, Xiangling; Si, Jianxiao; Huang, Shihua; Wu, Zheng; Zhu, Chenchen

    2011-07-01

    We deposited tantalum oxide film on a laminate structure composed of a Si substrate and a piezoelectric 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 single crystal and achieved in situ modulation of the resistance and capacitance of the Ta2O5 film. The modulation arises from the induced lattice strain in the Ta2O5 film, which is induced by the electric-field-induced strain in the piezoelectric crystal. Under an external electric field of ˜2 kV/cm, the longitudinal gauge factor of the Ta2O5 film is ˜3300. The control of the strain using the converse piezoelectric effect may be further extended to tune the intrinsic strain of other oxide thin films.

  6. Conversion of Methane to Methanol and Ethanol over Nickel Oxide on Ceria-Zirconia Catalysts in a Single Reactor

    DOE PAGES

    Okolie, Chukwuemeka; Belhseine, Yasmeen F.; Lyu, Yimeng; ...

    2017-08-08

    Here, the conversion of methane into alcohols under moderate reaction conditions is a promising technology for converting stranded methane reserves into liquids that can be transported in pipelines and upgraded to value-added chemicals. We demonstrate that a catalyst consisting of small nickel oxide clusters supported on ceria-zirconia (NiO/CZ) can convert methane to methanol and ethanol in a single, steady-state process at 723 K using O 2 as an abundantly available oxidant. The presence of steam is required to obtain alcohols rather than CO 2 as the product of catalytic combustion. The unusual activity of this catalyst is attributed to themore » synergy between the small Lewis acidic NiO clusters and the redox-active CZ support, which also stabilizes the small NiO clusters.« less

  7. Apparatus and methods for direct conversion of gaseous hydrocarbons to liquids

    DOEpatents

    Kong, Peter C.; Lessing, Paul A.

    2006-04-25

    A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

  8. Improved photovoltaic performance from inorganic perovskite oxide thin films with mixed crystal phases

    NASA Astrophysics Data System (ADS)

    Chakrabartty, Joyprokash; Harnagea, Catalin; Celikin, Mert; Rosei, Federico; Nechache, Riad

    2018-05-01

    Inorganic ferroelectric perovskites are attracting attention for the realization of highly stable photovoltaic cells with large open-circuit voltages. However, the power conversion efficiencies of devices have been limited so far. Here, we report a power conversion efficiency of 4.20% under 1 sun illumination from Bi-Mn-O composite thin films with mixed BiMnO3 and BiMn2O5 crystal phases. We show that the photocurrent density and photovoltage mainly develop across grain boundaries and interfaces rather than within the grains. We also experimentally demonstrate that the open-circuit voltage and short-circuit photocurrent measured in the films are tunable by varying the electrical resistance of the device, which in turn is controlled by externally applying voltage pulses. The exploitation of multifunctional properties of composite oxides provides an alternative route towards achieving highly stable, high-efficiency photovoltaic solar energy conversion.

  9. Method for direct conversion of gaseous hydrocarbons to liquids

    DOEpatents

    Kong, Peter C.; Lessing, Paul A.

    2006-03-07

    A chemical reactor for direct conversion of hydrocarbons includes a dielectric barrier discharge plasma cell and a solid oxide electrochemical cell in fluid communication therewith. The discharge plasma cell comprises a pair of electrodes separated by a dielectric material and passageway therebetween. The electrochemical cell comprises a mixed-conducting solid oxide electrolyte membrane tube positioned between a porous cathode and a porous anode, and a gas inlet tube for feeding oxygen containing gas to the porous cathode. An inlet is provided for feeding hydrocarbons to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a light source for directing ultraviolet light into the discharge plasma cell and the electrochemical cell.

  10. HB-Line Plutonium Oxide Data Collection Strategy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watkins, R.; Varble, J.; Jordan, J.

    2015-05-26

    HB-Line and H-Canyon will handle and process plutonium material to produce plutonium oxide for feed to the Mixed Oxide Fuel Fabrication Facility (MFFF). However, the plutonium oxide product will not be transferred to the MFFF directly from HB-Line until it is packaged into a qualified DOE-STD-3013-2012 container. In the interim, HB-Line will load plutonium oxide into an inner, filtered can. The inner can will be placed in a filtered bag, which will be loaded into a filtered outer can. The outer can will be loaded into a certified 9975 with getter assembly in compliance with onsite transportation requirement, for subsequentmore » storage and transfer to the K-Area Complex (KAC). After DOE-STD-3013-2012 container packaging capabilities are established, the product will be returned to HB-Line to be packaged into a qualified DOE-STD-3013-2012 container. To support the transfer of plutonium oxide to KAC and then eventually to MFFF, various material and packaging data will have to be collected and retained. In addition, data from initial HB-Line processing operations will be needed to support future DOE-STD-3013-2012 qualification as amended by the HB-Line DOE Standard equivalency. As production increases, the volume of data to collect will increase. The HB-Line data collected will be in the form of paper copies and electronic media. Paper copy data will, at a minimum, consist of facility procedures, nonconformance reports (NCRs), and DCS print outs. Electronic data will be in the form of Adobe portable document formats (PDFs). Collecting all the required data for each plutonium oxide can will be no small effort for HB-Line, and will become more challenging once the maximum annual oxide production throughput is achieved due to the sheer volume of data to be collected. The majority of the data collected will be in the form of facility procedures, DCS print outs, and laboratory results. To facilitate complete collection of this data, a traveler form will be developed which identifies the required facility procedures, DCS print outs, and laboratory results needed to assemble a final data package for each HB-Line plutonium oxide interim oxide can. The data traveler may identify the specific values (data) required to be extracted from the collected facility procedures and DCS print outs. The data traveler may also identify associated criteria to be checked. Inevitably there will be procedure anomalies during the course of the HB-Line plutonium oxide campaign that will have to be addressed in a timely manner.« less

  11. Looking North at Reactor Number One and Air Vent on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking North at Reactor Number One and Air Vent on Fourth Floor of Oxide Building - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  12. Looking Northwest at First Floor Typical Wall and Ceiling Juncture ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Northwest at First Floor Typical Wall and Ceiling Juncture in Oxide Building and Loading Dock - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  13. IJS procedure for RELAP5 to TRACE input model conversion using SNAP

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prosek, A.; Berar, O. A.

    2012-07-01

    The TRAC/RELAP Advanced Computational Engine (TRACE) advanced, best-estimate reactor systems code developed by the U.S. Nuclear Regulatory Commission comes with a graphical user interface called Symbolic Nuclear Analysis Package (SNAP). Much of efforts have been done in the past to develop the RELAP5 input decks. The purpose of this study is to demonstrate the Institut 'Josef Stefan' (IJS) conversion procedure from RELAP5 to TRACE input model of BETHSY facility. The IJS conversion procedure consists of eleven steps and is based on the use of SNAP. For calculations of the selected BETHSY 6.2TC test the RELAP5/MOD3.3 Patch 4 and TRACE V5.0more » Patch 1 were used. The selected BETHSY 6.2TC test was 15.24 cm equivalent diameter horizontal cold leg break in the reference pressurized water reactor without high pressure and low pressure safety injection. The application of the IJS procedure for conversion of BETHSY input model showed that it is important to perform the steps in proper sequence. The overall calculated results obtained with TRACE using the converted RELAP5 model were close to experimental data and comparable to RELAP5/MOD3.3 calculations. Therefore it can be concluded, that proposed IJS conversion procedure was successfully demonstrated on the BETHSY integral test facility input model. (authors)« less

  14. Methemoglobinemia caused by 8-aminoquinoline drugs: DFT calculations suggest an analogy to H4B's role in nitric oxide synthase

    USDA-ARS?s Scientific Manuscript database

    We suggest a possible mechanism of how 8-aminoquinolines (8-AQ's) cause hemotoxicity by oxidizing hemoglobin to methemoglobin. In our DFT calculations, we found that 5-hydroxyprimaquine is able to donate an electron to O2 to facilitate its conversion to H2O2. Meanwhile, Fe(II) is oxidized to Fe(III)...

  15. Coupling of exothermic and endothermic reactions in oxidative conversion of natural gas into ethylene/olefins over diluted SrO/La{sub 2}O{sub 3}/SA5205 catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Choudhary, V.R.; Mulla, S.A.R.

    1997-09-01

    In the oxidative conversion of natural gas to ethylene/lower olefins over SrO (17.3 wt.%)/La{sub 2}O{sub 3} (17.9 wt.%)/SA5205 catalyst diluted with inert solid particles (inerts/catalyst(w/w) = 2.0) in the presence of limited O{sub 2}, the exothermic oxidative conversion reactions of natural gas are coupled with the endothermic C{sub 2+} hydrocarbon thermal cracking reactions for avoiding hot spot formation and eliminating heat removal problems. Because of this, the process is operated in the most energy-efficient and safe manner. The influence of various process variables (viz. temperature, NG/O{sub 2} and steam/NG ratios in feed, and space velocity) on the conversion of carbonmore » and also of the individual hydrocarbons in natural gas, the selectivity for C{sub 2}-C{sub 4} olefins, and also on the net heat of reactions in the process has been thoroughly investigated. By carrying out the process at 800--850 C in the presence of steam (H{sub 2}O/NG {le} 0.2) and using limited O{sub 2} in the feed (NG/O{sub 2} = 12--18), high selectivity for ethylene (about 60%) or C{sub 2}-C{sub 4} olefins (above 80%) at the carbon conversion (>15%) of practical interest could be achieved at high space velocity ({ge}34,000 cm{sup 3}/g (catalyst) h), requiring no external energy and also without forming coke or tar-like products. The net heat of reactions can be controlled and the process can be made mildly exothermic or even close to thermoneutral by manipulating the O{sub 2} concentration in the feed.« less

  16. Tunable catalytic properties of bi-functional mixed oxides in ethanol conversion to high value compounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ramasamy, Karthikeyan K.; Gray, Michel J.; Job, Heather M.

    2016-04-10

    tA highly versatile ethanol conversion process to selectively generate high value compounds is pre-sented here. By changing the reaction temperature, ethanol can be selectively converted to >C2alcohols/oxygenates or phenolic compounds over hydrotalcite derived bi-functional MgO–Al2O3cata-lyst via complex cascade mechanism. Reaction temperature plays a role in whether aldol condensationor the acetone formation is the path taken in changing the product composition. This article containsthe catalytic activity comparison between the mono-functional and physical mixture counterpart to thehydrotalcite derived mixed oxides and the detailed discussion on the reaction mechanisms.

  17. Synthesis of fluidized CO2 sorbents based on diamine coordinated to Metal-Organic Frameworks via direct conversion of metal oxides supported on mesoporous silica.

    PubMed

    Luz, Ignacio; Soukri, Mustapha; Lail, Marty

    2018-06-06

    A general and efficient method for shaping MOFs into fluidized forms has been developed via direct conversion of metal oxides supported on fluidized mesoporous silica. The resulting fluidized MOF hybrid materials containing diamines coordinated at the open metal sites have been studied as CO2 solid sorbents from post-combustion flue gas showing similar performance than their bulk counterparts. These novel fluidized MOF hybrid materials can be used for other applications involving fluidized bed reactor configurations, in which MOFs have never been considered. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Tunable catalytic properties of bi-functional mixed oxides in ethanol conversion to high value compounds

    DOE PAGES

    Ramasamy, Karthikeyan K.; Gray, Michel; Job, Heather; ...

    2016-02-03

    Here, a highly versatile ethanol conversion process to selectively generate high value compounds is presented here. By changing the reaction temperature, ethanol can be selectively converted to >C 2 alcohols/oxygenates or phenolic compounds over hydrotalcite derived bi-functional MgO–Al 2O 3 catalyst via complex cascade mechanism. Reaction temperature plays a role in whether aldol condensation or the acetone formation is the path taken in changing the product composition. This article contains the catalytic activity comparison between the mono-functional and physical mixture counterpart to the hydrotalcite derived mixed oxides and the detailed discussion on the reaction mechanisms.

  19. Chemical Conversion of Anhydrous Hydrogen Fluoride for Safe Disposal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blake, Thomas A.; Brauer, Carolyn S.; Bachmann, William J.

    A procedure for the safe conversion of a small (~ 1 gram) quantity of anhydrous hydrogen fluoride to calcium fluoride is described. The purpose of the conversion is to put the toxic, corrosive, gaseous compound into a chemical form that is a less toxic solid (calcium fluoride) and easier to dispose of. The hydrogen fluoride, which was contained in a 50 cc metal sample cylinder, was drawn by a small mechanical vacuum pump through an all-metal gas manifold and into a metal trap containing alternating layers of calcium oxide powder and Teflon turnings. The anhydrous hydrogen fluoride reacts with themore » calcium oxide to produce calcium fluoride and water vapor. Because some of the calcium oxide powder was drawn out of the trap and into the vacuum tubing, it was not possible to quantify the amount of anhydrous hydrogen fluoride converted to calcium fluoride. However, it was noted that there was a temperature rise in the trap when the gas was flowing through it, and no HF gas was detected at the vacuum pump exhaust at this time using a colorimetric Dräger tube. The trap was sealed and disposed of as solid chemical waste.« less

  20. Preparation and Layer-by-Layer Solution Deposition of Cu(In,Ga)O2 Nanoparticles with Conversion to Cu(In,Ga)S2 Films

    PubMed Central

    Dressick, Walter J.; Soto, Carissa M.; Fontana, Jake; Baker, Colin C.; Myers, Jason D.; Frantz, Jesse A.; Kim, Woohong

    2014-01-01

    We present a method of Cu(In,Ga)S2 (CIGS) thin film formation via conversion of layer-by-layer (LbL) assembled Cu-In-Ga oxide (CIGO) nanoparticles and polyelectrolytes. CIGO nanoparticles were created via a novel flame-spray pyrolysis method using metal nitrate precursors, subsequently coated with polyallylamine (PAH), and dispersed in aqueous solution. Multilayer films were assembled by alternately dipping quartz, Si, and/or Mo substrates into a solution of either polydopamine (PDA) or polystyrenesulfonate (PSS) and then in the CIGO-PAH dispersion to fabricate films as thick as 1–2 microns. PSS/CIGO-PAH films were found to be inadequate due to weak adhesion to the Si and Mo substrates, excessive particle diffusion during sulfurization, and mechanical softness ill-suited to further processing. PDA/CIGO-PAH films, in contrast, were more mechanically robust and more tolerant of high temperature processing. After LbL deposition, films were oxidized to remove polymer and sulfurized at high temperature under flowing hydrogen sulfide to convert CIGO to CIGS. Complete film conversion from the oxide to the sulfide is confirmed by X-ray diffraction characterization. PMID:24941104

  1. Acetylacetone as an efficient electron shuttle for concerted redox conversion of arsenite and nitrate in the opposite direction.

    PubMed

    Chen, Zhihao; Song, Xiaojie; Zhang, Shujuan; Wu, Bingdang; Zhang, Guoyang; Pan, Bingcai

    2017-11-01

    The redox conversion of arsenite and nitrate has direct effects on their potential environment risks. Due to the similar reduction potentials, there are few technologies that can simultaneously oxidize arsenite and reduce nitrate in one process. Here, we demonstrate that a diketone-mediated photochemical process could efficiently do this. A combined experimental and theoretical investigation was conducted to elucidate the mechanisms behind the redox conversion in the UV/acetylacetone (AA) process. Our key finding is that UV irradiation significantly changed the redox potential of AA. The excited AA, 3 (AA)*, acted as a semiquinone radical-like electron shuttle. For arsenite oxidation, the efficiency of 3 (AA)* was 1-2 orders of magnitude higher than those of quinone-type electron shuttles, whereas the consumption of AA was 2-4 orders of magnitude less than those of benzonquinones. The oxidation of arsenite and reduction of nitrate could be both accelerated when they existed together in UV/AA process. The results indicate that small diketones are some neglected but potent electron shuttles of great application potential in regulating aquatic redox reactions with the combination of UV irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Alterations to mitochondrial fatty-acid use in skeletal muscle after chronic exposure to hypoxia depend on metabolic phenotype.

    PubMed

    Malgoyre, Alexandra; Chabert, Clovis; Tonini, Julia; Koulmann, Nathalie; Bigard, Xavier; Sanchez, Hervé

    2017-03-01

    We investigated the effects of chronic hypoxia on the maximal use of and sensitivity of mitochondria to different substrates in rat slow-oxidative (soleus, SOL) and fast-glycolytic (extensor digitorum longus, EDL) muscles. We studied mitochondrial respiration in situ in permeabilized myofibers, using pyruvate, octanoate, palmitoyl-carnitine (PC), or palmitoyl-coenzyme A (PCoA). The hypophagia induced by hypoxia may also alter metabolism. Therefore, we used a group of pair-fed rats (reproducing the same caloric restriction, as observed in hypoxic animals), in addition to the normoxic control fed ad libitum. The resting respiratory exchange ratio decreased after 21 days of exposure to hypobaric hypoxia (simulated elevation of 5,500 m). The respiration supported by pyruvate and octanoate were unaffected. In contrast, the maximal oxidative respiratory rate for PCoA, the transport of which depends on carnitine palmitoyltransferase 1 (CPT-1), decreased in the rapid-glycolytic EDL and increased in the slow-oxidative SOL, although hypoxia improved affinity for this substrate in both muscle types. PC and PCoA were oxidized similarly in normoxic EDL, whereas chronic hypoxia limited transport at the CPT-1 step in this muscle. The effects of hypoxia were mediated by caloric restriction in the SOL and by hypoxia itself in the EDL. We conclude that improvements in mitochondrial affinity for PCoA, a physiological long-chain fatty acid, would facilitate fatty-acid use at rest after chronic hypoxia independently of quantitative alterations of mitochondria. Conversely, decreasing the maximal oxidation of PCoA in fast-glycolytic muscles would limit fatty-acid use during exercise. NEW & NOTEWORTHY Affinity for low concentrations of long-chain fatty acids (LCFA) in mitochondria skeletal muscles increases after chronic hypoxia. Combined with a lower respiratory exchange ratio, this suggests facility for fatty acid utilization at rest. This fuel preference is related to caloric restriction in oxidative muscle and to hypoxia in glycolytic one. In contrast, maximal oxidation for LCFA is decreased by chronic hypoxia in glycolytic muscle and can explain glucose dependence at exercise. Copyright © 2017 the American Physiological Society.

  3. To Build or Not to Build: Addressing Facilities Needs While Controlling Costs

    ERIC Educational Resources Information Center

    Kadamus, James A.

    2015-01-01

    When trustees, presidents, and senior college administrators meet, one topic dominates the conversation: how to keep education quality high and costs down. To keep quality high, college leaders need to have strong faculties and state-of-the-art facilities for teaching and research. Quality counts but it also costs, and that is where the pressures…

  4. 10 CFR 60.132 - Additional design criteria for surface facilities in the geologic repository operations area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... conversion to a form suitable for disposal at an alternative site in accordance with any regulations that are... 10 Energy 2 2014-01-01 2014-01-01 false Additional design criteria for surface facilities in the geologic repository operations area. 60.132 Section 60.132 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED...

  5. 10 CFR 60.132 - Additional design criteria for surface facilities in the geologic repository operations area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... conversion to a form suitable for disposal at an alternative site in accordance with any regulations that are... 10 Energy 2 2012-01-01 2012-01-01 false Additional design criteria for surface facilities in the geologic repository operations area. 60.132 Section 60.132 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED...

  6. 10 CFR 60.132 - Additional design criteria for surface facilities in the geologic repository operations area.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... conversion to a form suitable for disposal at an alternative site in accordance with any regulations that are... 10 Energy 2 2013-01-01 2013-01-01 false Additional design criteria for surface facilities in the geologic repository operations area. 60.132 Section 60.132 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED...

  7. 10 CFR 60.132 - Additional design criteria for surface facilities in the geologic repository operations area.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... conversion to a form suitable for disposal at an alternative site in accordance with any regulations that are... 10 Energy 2 2011-01-01 2011-01-01 false Additional design criteria for surface facilities in the geologic repository operations area. 60.132 Section 60.132 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED...

  8. Surface engineering of hierarchical platinum-cobalt nanowires for efficient electrocatalysis

    DOE PAGES

    Bu, Lingzheng; Guo, Shaojun; Zhang, Xu; ...

    2016-06-29

    Despite intense research in past decades, the lack of high-performance catalysts for fuel cell reactions remains a challenge in realizing fuel cell technologies for transportation applications. Here we report a facile strategy for synthesizing hierarchical platinum-cobalt nanowires with high-index, platinum-rich facets and ordered intermetallic structure. These structural features enable unprecedented performance for the oxygen reduction and alcohol oxidation reactions. The specific/mass activities of the platinum-cobalt nanowires for oxygen reduction reaction are 39.6/33.7 times higher than commercial Pt/C catalyst, respectively. Density functional theory simulations reveal that the active threefold hollow sites on the platinum-rich high-index facets provide an additional factor inmore » enhancing oxygen reduction reaction activities. The nanowires are stable in the electrochemical conditions and also thermally stable. Furthermore, this work may represent a key step towards scalable production of high performance platinum-based nanowires for applications in catalysis and energy conversion.« less

  9. 13.2% efficiency Si nanowire/PEDOT:PSS hybrid solar cell using a transfer-imprinted Au mesh electrode

    PubMed Central

    Park, Kwang-Tae; Kim, Han-Jung; Park, Min-Joon; Jeong, Jun-Ho; Lee, Jihye; Choi, Dae-Geun; Lee, Jung-Ho; Choi, Jun-Hyuk

    2015-01-01

    In recent years, inorganic/organic hybrid solar cell concept has received growing attention for alternative energy solution because of the potential for facile and low-cost fabrication and high efficiency. Here, we report highly efficient hybrid solar cells based on silicon nanowires (SiNWs) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) using transfer-imprinted metal mesh front electrodes. Such a structure increases the optical absorption and shortens the carrier transport distance, thus, it greatly increases the charge carrier collection efficiency. Compared with hybrid cells formed using indium tin oxide (ITO) electrodes, we find an increase in power conversion efficiency from 5.95% to 13.2%, which is attributed to improvements in both the electrical and optical properties of the Au mesh electrode. Our fabrication strategy for metal mesh electrode is suitable for the large-scale fabrication of flexible transparent electrodes, paving the way towards low-cost, high-efficiency, flexible solar cells. PMID:26174964

  10. Top-Down Strategy to Synthesize Mesoporous Dual Carbon Armored MnO Nanoparticles for Lithium-Ion Battery Anodes.

    PubMed

    Zhang, Wei; Li, Jiannian; Zhang, Jie; Sheng, Jinzhi; He, Ting; Tian, Meiyue; Zhao, Yufeng; Xie, Changjun; Mai, Liqiang; Mu, Shichun

    2017-04-12

    To overcome inferior rate capability and cycle stability of MnO-based materials as a lithium-ion battery anode associated with the pulverization and gradual aggregation during the conversion process, we constructed robust mesoporous N-doped carbon (N-C) protected MnO nanoparticles on reduced graphene oxide (rGO) (MnO@N-C/rGO) by a simple top-down incorporation strategy. Such dual carbon protection endows MnO@N-C/rGO with excellent structural stability and enhanced charge transfer kinetics. At 100 mA g -1 , it exhibits superior rate capability as high as 864.7 mAh g -1 , undergoing the deep charge/discharge for 70 cycles and outstanding cyclic stability (after 1300 cyclic tests at 2000 mA g -1 ; 425.0 mAh g -1 remains, accompanying merely 0.004% capacity decay per cycle). This facile method provides a novel strategy for synthesis of porous electrodes by making use of highly insulating materials.

  11. Supercritical water oxidation of landfill leachate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang Shuzhong, E-mail: s_z_wang@yahoo.cn; Guo Yang; Chen Chongming

    2011-09-15

    Highlights: > Thermal analysis of NH{sub 3} in supercritical water oxidation reaction. > Research on the catalytic reaction of landfill leachate by using response surface method. > Kinetic research of supercritical water oxidation of NH{sub 3} with and without MnO{sub 2} catalyst. - Abstract: In this paper, ammonia as an important ingredient in landfill leachate was mainly studied. Based on Peng-Robinson formulations and Gibbs free energy minimization method, the estimation of equilibrium composition and thermodynamic analysis for supercritical water oxidation of ammonia (SCWO) was made. As equilibrium is reached, ammonia could be totally oxidized in SCW. N{sub 2} is themore » main product, and the formation of NO{sub 2} and NO could be neglected. The investigation on SCWO of landfill leachate was conducted in a batch reactor at temperature of 380-500 deg. C, reaction time of 50-300 s and pressure of 25 MPa. The effect of reaction parameters such as oxidant equivalent ratio, reaction time and temperature were investigated. The results showed that COD and NH{sub 3} conversion improved as temperature, reaction time and oxygen excess increased. Compared to organics, NH{sub 3} is a refractory compound in supercritical water. The conversion of COD and NH{sub 3} were higher in the presence of MnO{sub 2} than that without catalyst. The interaction between reaction temperature and time was analyzed by using response surface method (RSM) and the results showed that its influence on the NH{sub 3} conversion was relatively insignificant in the case without catalyst. A global power-law rate expression was regressed from experimental data to estimate the reaction rate of NH{sub 3}. The activation energy with and without catalyst for NH{sub 3} oxidation were 107.07 {+-} 8.57 kJ/mol and 83.22 {+-} 15.62 kJ/mol, respectively.« less

  12. Thermoelectric Oxide Modules (TOMs) for the Direct Conversion of Simulated Solar Radiation into Electrical Energy

    PubMed Central

    Tomeš, Petr; Trottmann, Matthias; Suter, Clemens; Aguirre, Myriam Heidi; Steinfeld, Aldo; Haueter, Philipp; Weidenkaff, Anke

    2010-01-01

    The direct conversion of concentrated high temperature solar heat into electrical energy was demonstrated with a series of four–leg thermoelectric oxide modules (TOM). These temperature stable modules were not yet optimized for high efficiency conversion, but served as proof-of-principle for high temperature conversion. They were constructed by connecting two p- (La1.98Sr0.02CuO4) and two n-type (CaMn0.98Nb0.02O3) thermoelements electrically in series and thermally in parallel. The temperature gradient ΔT was applied by a High–Flux Solar Simulator source (HFSS) which generates a spectrum similar to solar radiation. The influence of the graphite layer coated on the hot side of the Al2O3 substrate compared to the uncoated surface on ΔT, Pmax and η was studied in detail. The measurements show an almost linear temperature profile along the thermoelectric legs. The maximum output power of 88.8 mW was reached for a TOM with leg length of 5 mm at ΔT = 622 K. The highest conversion efficiency η was found for a heat flux of 4–8 W cm-2 and the dependence of η on the leg length was investigated.

  13. High efficiency thermal to electric energy conversion using selective emitters and spectrally tuned solar cells

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1992-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1500 K. Depending on the nature of parasitic losses, overall thermal-to-electric conversion efficiencies greater than 20 percent are feasible.

  14. Thermophotovoltaic conversion using selective infrared line emitters and large band gap photovoltaic devices

    DOEpatents

    Brandhorst, Jr., Henry W.; Chen, Zheng

    2000-01-01

    Efficient thermophotovoltaic conversion can be performed using photovoltaic devices with a band gap in the 0.75-1.4 electron volt range, and selective infrared emitters chosen from among the rare earth oxides which are thermally stimulated to emit infrared radiation whose energy very largely corresponds to the aforementioned band gap. It is possible to use thermovoltaic devices operating at relatively high temperatures, up to about 300.degree. C., without seriously impairing the efficiency of energy conversion.

  15. Selective Conversion of Biorefinery Lignin into Dicarboxylic Acids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Ruoshui; Guo, Mond; Zhang, Xiao

    The emerging biomass-to-biofuel conversion industry has created an urgent need for identifying new applications for biorefinery lignin. This paper demonstrates a new route to producing dicarboxylic acids from biorefinery lignin through chalcopyrite-catalyzed oxidation in a highly selective process. Up to 95 % selectivity towards stable dicarboxylic acids was obtained for several types of biorefinery lignin and model compounds under mild, environmentally friendly reaction conditions. The findings from this study paved a new avenue to biorefinery lignin conversions and applications.

  16. Amorphous transparent conducting oxides in context: Work function survey, trends, and facile modification

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yeh, T. C.; Zhu, Q.; Buchholz, D. B.

    2015-03-01

    The work functions of various amorphous and crystalline transparent conducting oxides (TCO5) were measured using Kelvin probe. The films, made by pulsed laser deposition, exhibited varying work functions dependent on the composition and deposition parameters. Tin oxide showed the largest work functions of the oxides measured, while zinc oxide showed the lowest. Binary and ternary combinations of the basis TCOs showed intermediate work functions dependent on the endpoint components. Amorphous TCO5, important in OPV and other technological applications, exhibited similar work functions to their crystalline counterparts. UV/ozone treatment of TCOs temporarily increased the work function, consistent with proposed defect mechanismsmore » associated with near-surface changes in carrier content and Fermi level. Finally, a method for facile adjustment of the work function of commercial TCOs by atomic layer deposition (ALD) capping layers was presented, illustrated by the growth of zinc oxide layers on commercial crystalline ITO films.« less

  17. Amorphous transparent conducting oxides in context: Work function survey, trends, and facile modification

    NASA Astrophysics Data System (ADS)

    Yeh, T. C.; Zhu, Q.; Buchholz, D. B.; Martinson, A. B.; Chang, R. P. H.; Mason, T. O.

    2015-03-01

    The work functions of various amorphous and crystalline transparent conducting oxides (TCOs) were measured using Kelvin probe. The films, made by pulsed laser deposition, exhibited varying work functions dependent on the composition and deposition parameters. Tin oxide showed the largest work functions of the oxides measured, while zinc oxide showed the lowest. Binary and ternary combinations of the basis TCOs showed intermediate work functions dependent on the endpoint components. Amorphous TCOs, important in OPV and other technological applications, exhibited similar work functions to their crystalline counterparts. UV/ozone treatment of TCOs temporarily increased the work function, consistent with proposed defect mechanisms associated with near-surface changes in carrier content and Fermi level. Finally, a method for facile adjustment of the work function of commercial TCOs by atomic layer deposition (ALD) capping layers was presented, illustrated by the growth of zinc oxide layers on commercial crystalline ITO films.

  18. Advancing the frontiers in nanocatalysis, biointerfaces, and renewable energy conversion by innovations of surface techniques.

    PubMed

    Somorjai, Gabor A; Frei, Heinz; Park, Jeong Y

    2009-11-25

    The challenge of chemistry in the 21st century is to achieve 100% selectivity of the desired product molecule in multipath reactions ("green chemistry") and develop renewable energy based processes. Surface chemistry and catalysis play key roles in this enterprise. Development of in situ surface techniques such as high-pressure scanning tunneling microscopy, sum frequency generation (SFG) vibrational spectroscopy, time-resolved Fourier transform infrared methods, and ambient pressure X-ray photoelectron spectroscopy enabled the rapid advancement of three fields: nanocatalysts, biointerfaces, and renewable energy conversion chemistry. In materials nanoscience, synthetic methods have been developed to produce monodisperse metal and oxide nanoparticles (NPs) in the 0.8-10 nm range with controlled shape, oxidation states, and composition; these NPs can be used as selective catalysts since chemical selectivity appears to be dependent on all of these experimental parameters. New spectroscopic and microscopic techniques have been developed that operate under reaction conditions and reveal the dynamic change of molecular structure of catalysts and adsorbed molecules as the reactions proceed with changes in reaction intermediates, catalyst composition, and oxidation states. SFG vibrational spectroscopy detects amino acids, peptides, and proteins adsorbed at hydrophobic and hydrophilic interfaces and monitors the change of surface structure and interactions with coadsorbed water. Exothermic reactions and photons generate hot electrons in metal NPs that may be utilized in chemical energy conversion. The photosplitting of water and carbon dioxide, an important research direction in renewable energy conversion, is discussed.

  19. Hydrogenation of CO 2 to methanol: Importance of metal–oxide and metal–carbide interfaces in the activation of CO 2

    DOE PAGES

    Rodriguez, José A.; Liu, Ping; Stacchiola, Dario J.; ...

    2015-09-30

    In this study, the high thermochemical stability of CO 2 makes it very difficult to achieve the catalytic conversion of the molecule into alcohols or other hydrocarbon compounds, which can be used as fuels or the starting point for the generation of fine chemicals. Pure metals and bimetallic systems used for the CO 2 → CH 3OH conversion usually bind CO 2 too weakly and, thus, show low catalytic activity. Here, we discuss a series of recent studies that illustrate the advantages of metal–oxide and metal–carbide interfaces when aiming at the conversion of CO2 into methanol. CeO x/Cu(111), Cu/CeO x/TiOmore » 2(110), and Au/CeO x/TiO 2(110) exhibit an activity for the CO 2 → CH 3OH conversion that is 2–3 orders of magnitude higher than that of a benchmark Cu(111) catalyst. In the Cu–ceria and Au–ceria interfaces, the multifunctional combination of metal and oxide centers leads to complementary chemical properties that open active reaction pathways for methanol synthesis. Efficient catalysts are also generated after depositing Cu and Au on TiC(001). In these cases, strong metal–support interactions modify the electronic properties of the admetals and make them active for the binding of CO 2 and its subsequent transformation into CH 3OH at the metal–carbide interfaces.« less

  20. 7 CFR 1450.211 - BCAP contract.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Establishment... biomass conversion facility does not become fully or partially operational. (g) Contracts may be...

  1. 7 CFR 1450.211 - BCAP contract.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Establishment... biomass conversion facility does not become fully or partially operational. (g) Contracts may be...

  2. 7 CFR 1450.211 - BCAP contract.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Establishment... biomass conversion facility does not become fully or partially operational. (g) Contracts may be...

  3. 7 CFR 1450.211 - BCAP contract.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Establishment... biomass conversion facility does not become fully or partially operational. (g) Contracts may be...

  4. 40 CFR 63.626 - Performance tests and compliance provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

  5. 40 CFR 63.626 - Performance tests and compliance provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

  6. 40 CFR 63.626 - Performance tests and compliance provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

  7. Directors' duty to obtain a fair price in the conversion of nonprofit hospitals.

    PubMed

    Tower, E S

    1997-01-01

    Boards of Directors of tax-exempt hospitals are increasingly struggling with whether to convert their facilities to for-profit status. Other than the traditional duties of loyalty and fair dealings imposed upon directors, there is currently little guidance to assure that boards obtain a fair price for the hospital in such conversions. The author provides recommendations to assure proper valuation.

  8. The SPEDE spectrometer

    NASA Astrophysics Data System (ADS)

    Papadakis, P.; Cox, D. M.; O'Neill, G. G.; Borge, M. J. G.; Butler, P. A.; Gaffney, L. P.; Greenlees, P. T.; Herzberg, R.-D.; Illana, A.; Joss, D. T.; Konki, J.; Kröll, T.; Ojala, J.; Page, R. D.; Rahkila, P.; Ranttila, K.; Thornhill, J.; Tuunanen, J.; Van Duppen, P.; Warr, N.; Pakarinen, J.

    2018-03-01

    The electron spectrometer, SPEDE, has been developed and will be employed in conjunction with the Miniball spectrometer at the HIE-ISOLDE facility, CERN. SPEDE allows for direct measurement of internal conversion electrons emitted in-flight, without employing magnetic fields to transport or momentum filter the electrons. Together with the Miniball spectrometer, it enables simultaneous observation of γ rays and conversion electrons in Coulomb excitation experiments using radioactive ion beams.

  9. Sucrose tricarboxylate by sonocatalysed TEMPO-mediated oxidation.

    PubMed

    Lemoine, S; Thomazeau, C; Joannard, D; Trombotto, S; Descotes, G; Bouchu, A; Queneau, Y

    2000-06-16

    Oxidation of sucrose by the NaOCl/TEMPO system provided sucrose tricarboxylate without the addition of sodium bromide as co-catalyst when high-frequency (500 kHz) ultrasound was applied, in contrast to very limited conversion without sonication. In the presence of sodium bromide, sonication also caused acceleration of the oxidation. The rate increase due to sonication of the oxidant system prior to sucrose addition suggests that ultrasound acts at the level of the formation of the nitrosonium ion, the active oxidising species in the catalytic cycle.

  10. Comparative Distribution and Retention of Arsenic in Arsenic (+3 Oxidation State) Methyltransferase Knockout and Wild Type Mice

    EPA Science Inventory

    The mouse arsenic (+3 oxidation state) methyltransferase (As3mt) gene encodes a ~ 43 kDa protein that catalyzes conversion of inorganic arsenic into methylated products. Heterologous expression of AS3MT or its silencing by RNA interference controls arsenic methylation phenotypes...

  11. Technology for satellite power conversion

    NASA Technical Reports Server (NTRS)

    Campbell, D. P.; Gouker, M. A.; Summers, C.; Gallagher, J. J.

    1984-01-01

    Techniques for satellite electromagnetic energy transfer and power conversion at millimeter and infrared wavelengths are discussed. The design requirements for rectenna receiving elements are reviewed for both coherent radiation sources and Earth thermal infrared emission. Potential power transmitters including gyrotrons, free electron lasers, and CO2 lasers are assessed along with the rectification properties of metal-oxide metal diode power converters.

  12. High-yield conversion of (R)-2-octanol from the corresponding racemate by stereoinversion using Candida rugosa.

    PubMed

    Nie, Yao; Xu, Yan; Qing Mu, Xiao; Tang, Yan; Jiang, Juan; Hao Sun, Zhi

    2005-01-01

    Whole cells of Candida rugosa catalyzed the conversion of (R)-2-octanol from the corresponding racemate with the optical purity of 97% e.e. and yield of 92% in 10 h. The product was formed through a stereoinversion involving enantioselective oxidation and asymmetric reduction with 2-octanone as the intermediate.

  13. Improving the efficiency of quantum-dot-sensitized solar cells by optimizing the growth time of the CuS counter electrode

    NASA Astrophysics Data System (ADS)

    Sunesh, Chozhidakath Damodharan; Gopi, Chandu V. V. M.; Muthalif, Mohammed Panthakkal Abdul; Kim, Hee-Je; Choe, Youngson

    2017-09-01

    CuS counter electrodes (CEs) were prepared to fabricate efficient quantum-dot-sensitized solar cells (QDSSCs) based on a CdS/CdSe photo sensitizer. The CEs were prepared on a fluorine-doped tin oxide (FTO) glass substrate by a facile chemical bath deposition (CBD) method by dissolving CuSO4·5H2O and CH3CSNH2 in water, followed by adding 0.25 mM polyvinylpyrrolidone (PVP). The CBD was performed at 60 °C for 1 h, 2 h, and 3 h, and the samples were labeled as CuS 1 h, CuS 2 h, and CuS 3 h, respectively. The QDSSCs were assembled using prepared CuS CEs and a TiO2/CdS/CdSe/ZnS photoanode, and the effect of the growth time of CuS CEs on the QDSSC performance was investigated. As the CuS growth time increases, the short-circuit current density (Jsc), fill factor (FF), and open-circuit voltage (Voc) of the QDSSCs gradually increases, leading to an enhanced power conversion efficiency (η). QDSSCs that use the CuS 2 h CE exhibit a high Jsc of 14.31 mA cm-2, Voc of 0.603 V, and FF of 0.49, which are higher than that using conventional Pt electrodes as well as CuS 1 h and CuS 3 h electrodes. The electrochemical impedance spectroscopy results show that the CuS 2 h CE exhibits an inferior charge transfer resistance of only 2.93 Ω, which is 33 times lesser than that of the Pt CE. The enhanced device performance of CuS 2 h is ascribed to the high catalytic activity and low charge transfer resistance of the CuS CE in the reduction process of oxidized polysulfide. Consequently, a superior power conversion efficiency of 4.27% is achieved for QDSSCs utilizing CuS 2 h.

  14. Promotion of Oxygen Reduction by Exsolved Silver Nanoparticles on a Perovskite Scaffold for Low-Temperature Solid Oxide Fuel Cells.

    PubMed

    Zhu, Yinlong; Zhou, Wei; Ran, Ran; Chen, Yubo; Shao, Zongping; Liu, Meilin

    2016-01-13

    Solid oxide fuel cells (SOFCs) have potential to be the cleanest and most efficient electrochemical energy conversion devices with excellent fuel flexibility. To make SOFC systems more durable and economically competitive, however, the operation temperature must be significantly reduced, which depends sensitively on the development of highly active electrocatalysts for oxygen reduction reaction (ORR) at low temperatures. Here we report a novel silver nanoparticle-decorated perovskite oxide, prepared via a facile exsolution process from a Sr0.95Ag0.05Nb0.1Co0.9O3-δ (SANC) perovskite precursor, as a highly active and robust ORR electrocatalyst for low-temperature SOFCs. The exsolved Sr0.95Ag0.05Nb0.1Co0.9O3-δ (denoted as e-SANC) electrode is very active for ORR, achieving a very low area specific resistance (∼0.214 Ω cm(2) at 500 °C). An anode-supported cell with the new heterostructured cathode demonstrates very high peak power density (1116 mW cm(-2) at 500 °C) and stable operation for 140 h at a current density of 625 mA cm(-2). The superior ORR activity and stability are attributed to the fast oxygen surface exchange kinetics and the firm adhesion of the Ag nanoparticles to the Sr0.95Nb0.1Co0.9O3-δ (SNC0.95) support. Moreover, the e-SANC cathode displays improved tolerance to CO2. These unique features make the new heterostructured material a highly promising cathode for low-temperature SOFCs.

  15. Transformation of Active Sites in Fe/SSZ-13 SCR Catalysts during Hydrothermal Aging: A Spectroscopic, Microscopic, and Kinetics Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kovarik, Libor; Washton, Nancy M.; Kukkadapu, Ravi

    Fe/SSZ-13 catalysts (Si/Al = 12, Fe loadings 0.37% and 1.20%) were prepared via solution ion-exchange, and hydrothermally aged at 600, 700 and 800 C. The fresh and aged catalysts were characterized with surface area/pore volume analysis, Mössbauer, solid-state MAS NMR, NO titration FTIR spectroscopies, and TEM and APT imaging. Hydrothermal aging causes dealumination of the catalysts, and transformation of various Fe sites. The latter include conversion of free Fe2+ ions to dimeric Fe(III) species, the agglomeration of isolated Fe-ions to Fe-oxide clusters, and incorporation of Al into the Fe-oxide species. These changes result in complex influences on standard SCR andmore » NO/NH3 oxidation reactions. In brief, mild aging causes catalyst performance enhancement for SCR, while harsh aging at 800 C deteriorates SCR performance. In comparison to Fe/zeolites more prone to hydrothermal degradation, this study demonstrates that via the utilization of highly hydrothermally stable Fe/SSZ-13 catalysts, more accurate correlations between various Fe species and their roles in SCR related chemistries can be made. The authors gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed in the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is operated for the US DOE by Battelle.« less

  16. Controllable synthesis of mesoporous multi-shelled ZnO microspheres as efficient photocatalysts for NO oxidation

    NASA Astrophysics Data System (ADS)

    Chen, Xiaolang; Zhang, Huiqiang; Zhang, Dieqing; Miao, Yingchun; Li, Guisheng

    2018-03-01

    The successful application of hierarchically porous structure in environmental treatment has provided new insights for solving environmental problems. Hierarchically structured semiconductor materials were considered as promising photocatalysts for NO oxidation in gas phase. Multi-shelled ZnO microspheres (MMSZ) were controllably shaped with hierarchically porous structures via a facile hydrothermal route using amino acid (N-Acetyl-D-Proline) as template and post-calcination treatment. Symmetric Ostwald ripening was used to explain the morphological evolution of hierarchical nanostructure. MMSZ was proved highly efficient for oxidizing NO (400 ppb) in gas phase under UV light irradiation with a much higher photocatalytic removal rate (77.3%) than that of the as-obtained ZnO crystals with other hierachically porous structures, owing to its higher photocurrent intensity. Such greatly enhanced photocatalytic activity can be assigned to the enhanced crystallinity of ZnO, mesopores and unique multi-shelled structure. Enhanced crystallinity promotes photogenerated charges under light irradiation. Mesoporous porosity can ensure enough light scattering between the shells. Multi-shelled structure endows ZnO with higher specific surface area and high frequency of multiple light reflection, resulting in more exposed active sites, higher light utilization efficiency, and fast separation efficiency of photogenerated charge carriers. The experimental results demonstrated that the photogenerated holes (h+) are the main active species. Hierarchically structured ZnO is not only contributed to directly use solar energy to solving various problems caused by atmospheric pollution, but also has potential applications in energy converse and storage including solar cells, lithium batteries, water-splitting, etc.

  17. In situ grown hierarchical 50%BiOCl/BiOI hollow flowerlike microspheres on reduced graphene oxide nanosheets for enhanced visible-light photocatalytic degradation of rhodamine B

    NASA Astrophysics Data System (ADS)

    Su, Xiangde; Yang, Jinjin; Yu, Xiang; Zhu, Yi; Zhang, Yuanming

    2018-03-01

    50%BiOCl/BiOI/reduced graphene oxide (50%BiOCl/BiOI/rGO) composite photocatalyst was synthesized successfully by a facile one-step solvothermal route in this work. Reduction of graphene oxide (GO) took place in the process of solvothermal reaction and a new Bi-C bond between rGO and 50%BiOCl/BiOI was formed. The introduction of rGO affected the morphology of 50%BiOCl/BiOI, resulting in the transformation of 50%BiOCl/BiOI from solid microspheres to hollow microspheres. Both the introduction of rGO and formation of 50%BiOCl/BiOI hollow microspheres can facilitate the light absorption. The strong interaction between 50%BiOCl/BiOI and rGO and the electrical conductivity of rGO greatly improved the effective separation of photogenerated carriers. Hence, GOB-5 demonstrated the highest photocatalytic activity which was over twice of the pristine 50%BiOCl/BiOI in the presence of visible light. Mechanism study revealed that 50%BiOCl/BiOI generated electrons and holes in the presence of visible light, and holes together with rad O2- generated from reduction of O2 by electrons degraded the pollutant directly. Overall, this work provides an excellent reference to the synthesis of chemically bonded BiOX/BiOY (X, Y = Cl, Br, I)/rGO nanocomposite and helps to promote their applications in environmental protection and photoelectric conversion.

  18. Facile synthesis of iron oxides/reduced graphene oxide composites: application for electromagnetic wave absorption at high temperature.

    PubMed

    Zhang, Lili; Yu, Xinxin; Hu, Hongrui; Li, Yang; Wu, Mingzai; Wang, Zhongzhu; Li, Guang; Sun, Zhaoqi; Chen, Changle

    2015-03-19

    Iron oxides/reduced graphene oxide composites were synthesized by facile thermochemical reactions of graphite oxide and FeSO4 · 7H2O. By adjusting reaction temperature, α-Fe2O3/reduced graphene oxide and Fe3O4/reduced graphene oxide composites can be obtained conveniently. Graphene oxide and reduced graphene oxide sheets were demonstrated to regulate the phase transition from α-Fe2O3 to Fe3O4 via γ-Fe2O3, which was reported for the first time. The hydroxyl groups attached on the graphene oxide sheets and H2 gas generated during the annealing of graphene oxide are believed to play an important role during these phase transformations. These samples showed good electromagnetic wave absorption performance due to their electromagnetic complementary effect. These samples possess much better electromagnetic wave absorption properties than the mixture of separately prepared Fe3O4 with rGO, suggesting the crucial role of synthetic method in determining the product properties. Also, these samples perform much better than commercial absorbers. Most importantly, the great stability of these composites is highly advantageous for applications as electromagnetic wave absorption materials at high temperatures.

  19. Facile synthesis of iron oxides/reduced graphene oxide composites: application for electromagnetic wave absorption at high temperature

    PubMed Central

    Zhang, Lili; Yu, Xinxin; Hu, Hongrui; Li, Yang; Wu, Mingzai; Wang, Zhongzhu; Li, Guang; Sun, Zhaoqi; Chen, Changle

    2015-01-01

    Iron oxides/reduced graphene oxide composites were synthesized by facile thermochemical reactions of graphite oxide and FeSO4·7H2O. By adjusting reaction temperature, α-Fe2O3/reduced graphene oxide and Fe3O4/reduced graphene oxide composites can be obtained conveniently. Graphene oxide and reduced graphene oxide sheets were demonstrated to regulate the phase transition from α-Fe2O3 to Fe3O4 via γ-Fe2O3, which was reported for the first time. The hydroxyl groups attached on the graphene oxide sheets and H2 gas generated during the annealing of graphene oxide are believed to play an important role during these phase transformations. These samples showed good electromagnetic wave absorption performance due to their electromagnetic complementary effect. These samples possess much better electromagnetic wave absorption properties than the mixture of separately prepared Fe3O4 with rGO, suggesting the crucial role of synthetic method in determining the product properties. Also, these samples perform much better than commercial absorbers. Most importantly, the great stability of these composites is highly advantageous for applications as electromagnetic wave absorption materials at high temperatures. PMID:25788158

  20. 47 CFR 3.2 - Terms and definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... forum for dealing with all aspects of international telecommunications, including radio, telecom services and telecom facilities. (m) Linking Coefficient. The ITU mandated conversion factor used to...

  1. 47 CFR 3.2 - Terms and definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... forum for dealing with all aspects of international telecommunications, including radio, telecom services and telecom facilities. (m) Linking Coefficient. The ITU mandated conversion factor used to...

  2. 47 CFR 3.2 - Terms and definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... forum for dealing with all aspects of international telecommunications, including radio, telecom services and telecom facilities. (m) Linking Coefficient. The ITU mandated conversion factor used to...

  3. 47 CFR 3.2 - Terms and definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... forum for dealing with all aspects of international telecommunications, including radio, telecom services and telecom facilities. (m) Linking Coefficient. The ITU mandated conversion factor used to...

  4. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells

    PubMed Central

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-01-01

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC). PMID:26218470

  5. Multicopper Oxidase Involvement in Both Mn(II) and Mn(III) Oxidation during Bacterial Formation of MnO2

    PubMed Central

    Soldatova, Alexandra V.; Butterfield, Cristina; Oyerinde, Oyeyemi F.; Tebo, Bradley M.; Spiro, Thomas G.

    2013-01-01

    Global cycling of environmental manganese requires catalysis by bacteria and fungi for MnO2 formation, since abiotic Mn(II) oxidation is slow under ambient conditions. Genetic evidence from several bacteria implicates multicopper oxidases (MCOs) as being required for MnO2 formation. However, MCOs catalyze one-electron oxidations, whereas conversion of Mn(II) to MnO2 is a two-electron process. Trapping experiments with pyrophosphate (PP), a Mn(III) chelator, have demonstrated that Mn(III) is an intermediate in Mn(II) oxidation when mediated by exosporium from the Mn-oxidizing bacterium Bacillus SG-1. The reaction of Mn(II) depends on O2 and is inhibited by azide, consistent with MCO catalysis. We show that the subsequent conversion of Mn(III) to MnO2 also depends on O2 and is inhibited by azide. Thus, both oxidation steps appear to be MCO-mediated, likely by the same enzyme, indicated by genetic evidence to be the MnxG gene product. We propose a model of how the manganese oxidase active site may be organized to couple successive electron transfers to the formation of polynuclear Mn(IV) complexes as precursors to MnO2 formation. PMID:22892957

  6. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells.

    PubMed

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-07-28

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).

  7. Catalytic wet air oxidation of bisphenol A solution in a batch-recycle trickle-bed reactor over titanate nanotube-based catalysts.

    PubMed

    Kaplan, Renata; Erjavec, Boštjan; Senila, Marin; Pintar, Albin

    2014-10-01

    Catalytic wet air oxidation (CWAO) is classified as an advanced oxidation process, which proved to be highly efficient for the removal of emerging organic pollutant bisphenol A (BPA) from water. In this study, BPA was successfully removed in a batch-recycle trickle-bed reactor over bare titanate nanotube-based catalysts at very short space time of 0.6 min gCAT g(-1). The as-prepared titanate nanotubes, which underwent heat treatment at 600 °C, showed high activity for the removal of aqueous BPA. Liquid-phase recycling (5- or 10-fold recycle) enabled complete BPA conversion already at 200 °C, together with high conversion of total organic carbon (TOC), i.e., 73 and 98 %, respectively. The catalyst was chemically stable in the given range of operating conditions for 189 h on stream.

  8. Takovite-aluminosilicate-Cr materials prepared by adsorption of Cr3+ from industrial effluents as catalysts for hydrocarbon oxidation reactions.

    PubMed

    Ciuffi, Katia J; de Faria, Emerson H; Marçal, Liziane; Rocha, Lucas A; Calefi, Paulo S; Nassar, Eduardo J; Pepe, Iuri; da Rocha, Zênis N; Vicente, Miguel A; Trujillano, Raquel; Gil, Antonio; Korili, Sophia A

    2012-05-01

    The catalytic efficiency of takovite-aluminosilicate-chromium catalysts obtained by adsorption of Cr(3+) ions from aqueous solutions by a takovite-aluminosilicate nanocomposite adsorbent is reported. The adsorbent was synthesized by the coprecipitation method. The catalytic activity of the final Cr-catalysts depended on the amount of adsorbed chromium. (Z)-cyclooctene conversion up to 90% with total selectivity for the epoxide was achieved when the oxidation was carried out with hydrogen peroxide, at room temperature. After five consecutive runs, the catalysts maintained high activity, although after the sixth reuse, the epoxide yields strongly decreased to 35%. The catalysts were also efficient for cyclohexane oxidation, reaching up to 18% conversion, with cyclohexanone/cyclohexanol selectivity close to 1.2. On the whole, their use as catalysts gives a very interesting application for the solids obtained by adsorption of a contaminant cation such as Cr(3+).

  9. Design Principles for Covalent Organic Frameworks as Efficient Electrocatalysts in Clean Energy Conversion and Green Oxidizer Production.

    PubMed

    Lin, Chun-Yu; Zhang, Lipeng; Zhao, Zhenghang; Xia, Zhenhai

    2017-05-01

    Covalent organic frameworks (COFs), an emerging class of framework materials linked by covalent bonds, hold potential for various applications such as efficient electrocatalysts, photovoltaics, and sensors. To rationally design COF-based electrocatalysts for oxygen reduction and evolution reactions in fuel cells and metal-air batteries, activity descriptors, derived from orbital energy and bonding structures, are identified with the first-principle calculations for the COFs, which correlate COF structures with their catalytic activities. The calculations also predict that alkaline-earth metal-porphyrin COFs could catalyze the direct production of H 2 O 2 , a green oxidizer and an energy carrier. These predictions are supported by experimental data, and the design principles derived from the descriptors provide an approach for rational design of new electrocatalysts for both clean energy conversion and green oxidizer production. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Small molecule solution-processed bulk heterojunction solar cells with inverted structure using porphyrin donor

    NASA Astrophysics Data System (ADS)

    Yamamoto, Takaki; Hatano, Junichi; Nakagawa, Takafumi; Yamaguchi, Shigeru; Matsuo, Yutaka

    2013-01-01

    Utilizing tetraethynyl porphyrin derivative (TE-Por) as a small molecule donor material, we fabricated a small molecule solution-processed bulk heterojunction (BHJ) solar cell with inverted structure, which exhibited 1.6% power conversion efficiency (JSC (short-circuit current) = 4.6 mA/cm2, VOC (open-circuit voltage) = 0.90 V, and FF (fill factor) = 0.39) in the device configuration indium tin oxide/TiOx (titanium sub-oxide)/[6,6]-phenyl-C61-butyric acid methyl ester:TE-Por (5:1)/MoOx (molybdenum sub-oxide)/Au under AM1.5 G illumination at 100 mW/cm2. Without encapsulation, the small molecule solution-processed inverted BHJ solar cell also showed remarkable durability to air, where it kept over 73% of its initial power conversion efficiency after storage for 28 days under ambient atmosphere in the dark.

  11. Facile synthesis of porous Pt-Pd nanospheres supported on reduced graphene oxide nanosheets for enhanced methanol electrooxidation

    NASA Astrophysics Data System (ADS)

    Li, Shan-Shan; Lv, Jing-Jing; Hu, Yuan-Yuan; Zheng, Jie-Ning; Chen, Jian-Rong; Wang, Ai-Jun; Feng, Jiu-Ju

    2014-02-01

    In this study, a simple, facile, and effective wet-chemical strategy was developed in the synthesis of uniform porous Pt-Pd nanospheres (Pt-Pd NSs) supported on reduced graphene oxide nanosheets (RGOs) under ambient temperature, where octylphenoxypolye thoxyethanol (NP-40) is used as a soft template, without any seed, organic solvent or special instruments. The as-prepared nanocomposites display enhanced electrocatalytic activity and good stability toward methanol oxidation, compared with commercial Pd/C and Pt/C catalysts. This strategy may open a new route to design and prepare advanced electrocatalysts for fuel cells.

  12. Facile synthesis of hierarchical dendritic PtPd nanogarlands supported on reduced graphene oxide with enhanced electrocatalytic properties

    NASA Astrophysics Data System (ADS)

    Li, Shan-Shan; Zheng, Jie-Ning; Ma, Xiaohong; Hu, Yuan-Yuan; Wang, Ai-Jun; Chen, Jian-Rong; Feng, Jiu-Ju

    2014-05-01

    A simple and facile method is developed for one-pot preparation of hierarchical dendritic PtPd nanogarlands supported on reduced graphene oxide (PtPd/RGO) at room temperature, without using any seed, organic solvent, or complex apparatus. It is found that octylphenoxypolyethoxyethanol (NP-40) as a soft template and its amount are critical to the formation of PtPd garlands. The as-prepared nanocomposites are further applied to methanol and ethanol oxidation with significantly enhanced electrocatalytic activity and better stability in alkaline media.A simple and facile method is developed for one-pot preparation of hierarchical dendritic PtPd nanogarlands supported on reduced graphene oxide (PtPd/RGO) at room temperature, without using any seed, organic solvent, or complex apparatus. It is found that octylphenoxypolyethoxyethanol (NP-40) as a soft template and its amount are critical to the formation of PtPd garlands. The as-prepared nanocomposites are further applied to methanol and ethanol oxidation with significantly enhanced electrocatalytic activity and better stability in alkaline media. Electronic supplementary information (ESI) available: Experimental section, Fig. S1-S12 and Tables S1 and S2. See DOI: 10.1039/c3nr06808k

  13. Chemoselective catalytic conversion of glycerol as a biorenewable source to valuable commodity chemicals.

    PubMed

    Zhou, Chun-Hui Clayton; Beltramini, Jorge N; Fan, Yong-Xian; Lu, G Q Max

    2008-03-01

    New opportunities for the conversion of glycerol into value-added chemicals have emerged in recent years as a result of glycerol's unique structure, properties, bioavailability, and renewability. Glycerol is currently produced in large amounts during the transesterification of fatty acids into biodiesel and as such represents a useful by-product. This paper provides a comprehensive review and critical analysis on the different reaction pathways for catalytic conversion of glycerol into commodity chemicals, including selective oxidation, selective hydrogenolysis, selective dehydration, pyrolysis and gasification, steam reforming, thermal reduction into syngas, selective transesterification, selective etherification, oligomerization and polymerization, and conversion of glycerol into glycerol carbonate.

  14. Methane-Oxidizing Enzymes: An Upstream Problem in Biological Gas-to-Liquids Conversion

    PubMed Central

    Lawton, Thomas J.; Rosenzweig, Amy C.

    2017-01-01

    Biological conversion of natural gas to liquids (Bio-GTL) represents an immense economic opportunity. In nature, aerobic methanotrophic bacteria and anaerobic archaea are able to selectively oxidize methane using methane monooxygenase (MMO) and methyl coenzyme M reductase (MCR) enzymes. Although significant progress has been made toward genetically manipulating these organisms for biotechnological applications, the enzymes themselves are slow, complex, and not recombinantly tractable in traditional industrial hosts. With turnover numbers of 0.16–13 s−1, these enzymes pose a considerable upstream problem in the biological production of fuels or chemicals from methane. Methane oxidation enzymes will need to be engineered to be faster to enable high volumetric productivities; however, efforts to do so and to engineer simpler enzymes have been minimally successful. Moreover, known methane-oxidizing enzymes have different expression levels, carbon and energy efficiencies, require auxiliary systems for biosynthesis and function, and vary considerably in terms of complexity and reductant requirements. The pros and cons of using each methane-oxidizing enzyme for Bio-GTL are considered in detail. The future for these enzymes is bright, but a renewed focus on studying them will be critical to the successful development of biological processes that utilize methane as a feedstock. PMID:27366961

  15. Methane-Oxidizing Enzymes: An Upstream Problem in Biological Gas-to-Liquids Conversion.

    PubMed

    Lawton, Thomas J; Rosenzweig, Amy C

    2016-08-03

    Biological conversion of natural gas to liquids (Bio-GTL) represents an immense economic opportunity. In nature, aerobic methanotrophic bacteria and anaerobic archaea are able to selectively oxidize methane using methane monooxygenase (MMO) and methyl coenzyme M reductase (MCR) enzymes. Although significant progress has been made toward genetically manipulating these organisms for biotechnological applications, the enzymes themselves are slow, complex, and not recombinantly tractable in traditional industrial hosts. With turnover numbers of 0.16-13 s(-1), these enzymes pose a considerable upstream problem in the biological production of fuels or chemicals from methane. Methane oxidation enzymes will need to be engineered to be faster to enable high volumetric productivities; however, efforts to do so and to engineer simpler enzymes have been minimally successful. Moreover, known methane-oxidizing enzymes have different expression levels, carbon and energy efficiencies, require auxiliary systems for biosynthesis and function, and vary considerably in terms of complexity and reductant requirements. The pros and cons of using each methane-oxidizing enzyme for Bio-GTL are considered in detail. The future for these enzymes is bright, but a renewed focus on studying them will be critical to the successful development of biological processes that utilize methane as a feedstock.

  16. Long-Term Climate Implications of Persistent Loss of Tropical Peat Carbon Following Land Use Conversion

    NASA Astrophysics Data System (ADS)

    Frolking, S. E.; Dommain, R.; Glaser, P. H.; Joos, F.; Jeltsch-Thommes, A.

    2016-12-01

    The climate mitigation potential of tropical peatlands has gained increased attention as Southeast Asian tropical peat swamp forests are being deforested, drained and burned at very high rates, causing globally significant carbon dioxide (CO2) emissions to the atmosphere. We used a simple force-restore model to represent the perturbation to the atmospheric CO2 and CH4 burdens, and net radiative forcing, resulting from long-term conversion of tropical peat swamp forests to oil palm or acacia plantations. Drainage ditches are installed in land-use conversion to both oil palm and acacia, leading to a persistent change in the system greenhouse gas balance with the atmosphere. Drainage causes the net CO2 exchange to switch from a weak sink (removal from the atmosphere) in the accumulating peat of a swamp forest to a relatively strong source as the peat is oxidized. CH4 emissions increase due to relatively high emissions from the ditches themselves. For these systems, persistent CO2 fluxes have a much stronger impact on atmospheric radiative forcing than do the CH4 fluxes. Prior to conversion, slow peat accumulation (net CO2 uptake) over millennia establishes a slowly increasing net radiative cooling perturbation to the atmosphere. Upon conversion, CO2 loss rates are 16-32 times higher than pre-conversion CO2 uptake rates. Rapid loss rates cause the net radiative forcing perturbation to quickly (decades) become a net warming, which can persist for many centuries after the peat has all been oxidized.

  17. Advance concepts for conversion of syngas to liquids. Quarterly progress report No. 4, July 30, 1995--October 29, 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pei-Shing Eugene Dai; Petty, R.H.; Ingram, C.

    Substitution of transition metals for either aluminum and/or phosphorus in the AlPO{sub 4}-11 framework is found to afford novel heterogeneous catalysts for liquid phase hydroxylation of phenol with hydrogen peroxide. AlPO{sub 4}-11 is more active than SAPO-11 and MgAPO-11 for phenol conversion to hydroquinone. The Bronsted acid sites of SAPO-11 and MgAPO-11 may promote the decomposition of hydrogen peroxide to water and oxygen, thus leading to lower phenol conversions. Substitution of divalent and trivalent metal cations, such as Fe, Co and Mn appears to significantly improve the conversion of phenol. The activity follows the order of FeAPO-11>FeMnAPO-11>CoAPO-11>MnAPO-11{much_gt}ALPO{sub 4}-11. FeAPO-11, FeMnAPO-11more » and AlPO{sub 4}-11 give similar product selectivities of about 1:1 hydroquitione (HQ) to catechol (CT). MnAPO-11 and CoAPO-11 favor the production of catechol, particularly at low conversions. FeAPO-11 and TS-1 (titanium silicate with MFI topology) are comparable for the phenol conversions with TS-1 giving higher selectivities toward hydroquinone. The external surfaces of the catalysts plays a significant role in these oxidation reactions. MeAPO molecular sieves may be complementary to the metal silicalite catalysts for the catalytic oxidations in the manufacture of fine chemicals.« less

  18. Credit PSR. This photograph displays the south and east facades ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit PSR. This photograph displays the south and east facades of the storage facility as seen when looking to the west northwest (288°). The concrete pit in the foreground is a catch basin designed to hold run-off from spilled oxidizers or clean-up operations, thus preventing them from contaminating the soil - Jet Propulsion Laboratory Edwards Facility, Solid Oxidizer Storage, Edwards Air Force Base, Boron, Kern County, CA

  19. A Guide for Developing Standard Operating Job Procedures for the Activated Sludge - Aeration & Sedimentation Process Wastewater Treatment Facility. SOJP No. 5.

    ERIC Educational Resources Information Center

    Mason, George J.

    This guide for developing standard operating job procedures for wastewater treatment facilities is devoted to the activated sludge aeration and sedimentation process. This process is for conversion of nonsettleable and nonfloatable materials in wastewater to settleable, floculated biological groups and separation of the settleable solids from the…

  20. 7 CFR 1450.106 - Payments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS BIOMASS CROP ASSISTANCE PROGRAM (BCAP) Matching Payments... the qualified biomass conversion facility for the market-based sale of eligible material in an amount...

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