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1

Oxidation Resistant Graphite Studies  

SciTech Connect (OSTI)

The Very High Temperature Reactor (VHTR) Graphite Research and Development Program is investigating doped nuclear graphite grades exhibiting oxidation resistance. During a oxygen ingress accident the oxidation rates of the high temperature graphite core region would be extremely high resulting in significant structural damage to the core. Reducing the oxidation rate of the graphite core material would reduce the structural effects and keep the core integrity intact during any air-ingress accident. Oxidation testing of graphite doped with oxidation resistant material is being conducted to determine the extent of oxidation rate reduction. Nuclear grade graphite doped with varying levels of Boron-Carbide (B4C) was oxidized in air at nominal 740°C at 10/90% (air/He) and 100% air. The oxidation rates of the boronated and unboronated graphite grade were compared. With increasing boron-carbide content (up to 6 vol%) the oxidation rate was observed to have a 20 fold reduction from unboronated graphite. Visual inspection and uniformity of oxidation across the surface of the specimens were conducted. Future work to determine the remaining mechanical strength as well as graphite grades with SiC doped material are discussed.

W. Windes; R. Smith

2014-07-01T23:59:59.000Z

2

RecA-mediated SOS induction requires an extended filament conformation but no ATP hydrolysis  

E-Print Network [OSTI]

RecA-mediated SOS induction requires an extended filament conformation but no ATP hydrolysis filament on single-stranded DNA and hydrolyzes ATP. The RecA K72R (recA2201) muta- tion eliminates in the presence of ATP. Strains with this mutation do not undergo SOS induction in vivo. We have combined the K72R

Cox, Michael M.

3

Oxides: neutron and synchrotron X-ray diffraction studies  

Science Journals Connector (OSTI)

......the opal silica-water system. Keywords...oxides, opal silica-water system Received 11...order to perform advanced structure studies...oxides containing water (superionic non-stoichiometric...presence of very heavy atoms and to distin...using the IBR pulsed reactor in structure analysis......

Izabela M. Sosnowska; Makoto Shiojiri

1999-01-01T23:59:59.000Z

4

An EPR study of ¹?O? on magnesium oxide  

E-Print Network [OSTI]

AN EPR STUDY OF 0 ON MAGNESIUM OXIDE A Thesis by NING-SEW WONG Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1971 Major Subject: Chemistry AN EPR... STUDY OF 0 ON MAGNESIUM OXIDE A Thesis by NING-BEN WONG Approved as to style and content by: (Chairman of Committe (Head of Department) (Member) (Member) May 1971 ABSTRACT 17 An EPR Study of 0 on Magnesium Oxide (May, 1971) Ning-Bew Wong, B...

Wong, Ning-Bew

2012-06-07T23:59:59.000Z

5

In Situ Studies of Fuel Oxidation in Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

In Situ Studies of Fuel Oxidation in Solid Oxide Fuel Cells ... Re-optimization of the Raman signal shows two broad, strong features in the OCV spectrum indicating large amounts of disordered graphite as evidenced by a broad D band (at 1350 cm-1) accompanying the G band (at 1585 cm-1) (Figure 2, right panel). ... intensities from a nonresonant, bond polarizability model optimized for sp2 carbon are also in qual. ...

Michael B. Pomfret; Jeffrey C. Owrutsky; Robert A. Walker

2007-02-13T23:59:59.000Z

6

A DNA Damage-Induced, SOS-Independent Checkpoint Regulates Cell Division in Caulobacter crescentus  

E-Print Network [OSTI]

Cells must coordinate DNA replication with cell division, especially during episodes of DNA damage. The paradigm for cell division control following DNA damage in bacteria involves the SOS response where cleavage of the ...

Modell, Joshua W.

7

SRF Materials: Fundamental studies of interfacial oxidation chemistry of niobium  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ANL/FNAL/UC Collaboration meeting 27 Nov 2007 ANL/FNAL/UC Collaboration meeting 27 Nov 2007 SRF Materials: Fundamental studies of interfacial oxidation chemistry of niobium Lance Cooley - FNAL Mike Pellin, Jim Norem - ANL Steve Sibener - UC John Zasadzinski, Thomas Prolier - IIT f ANL/FNAL/UC Collaboration meeting 27 Nov 2007 May 2007 SRF Materials Workshop @ FNAL energized 2 collaborations being reported here * Atomic layer deposition of conformal coatings onto cavities (Pellin, Zasadzinski, Prolier, Norem, Antoine/Wu/Cooley) - Directly probe surface superconductivity (SC) via 1.5 K STM + XPS surface composition - Nb oxidation layer proximity effects! - ALD Al 2 O 3 coated cavity first, for oxidation control; multilayer- coated cavity later - A new philosophy: build up, not etch down - First annealing results reveal oxidation vs

8

Catalytic Partial Oxidation Pilot Plant Study  

Science Journals Connector (OSTI)

Foster Wheeler Corporation, 585 North Dairy Ashford Street, Houston, Texas 77079 ... This is accomplished in this study with a new reactor system named the catalytic hot oxygen reactor (CHOR). ... Studying the integration of the reactor with the rest of the plant and developing detailed process economics in parallel with the system development are necessary. ...

Vasilis Papavassiliou; Perry Pacouloute; KT Wu; Raymont Drnevich; Dionisios Vlachos; John Hemmings; Leo Bonnel

2009-11-24T23:59:59.000Z

9

Mechanistic Studies of Water Electrolysis and Hydrogen Electro-Oxidation on High Temperature Ceria-Based Solid Oxide  

E-Print Network [OSTI]

conversion devices with multicomponent materials (e.g., solid oxide fuel cells, electrolyzers-Based Solid Oxide Electrochemical Cells Chunjuan Zhang,,# Yi Yu,,# Michael E. Grass,,# Catherine Dejoie spectroscopy (APXPS) and a single-sided solid oxide electrochemical cell (SOC), we have studied the mechanism

Li, Weixue

10

Studies of oxidized hexagonal SiC surfaces and the  

Science Journals Connector (OSTI)

Results of recent photoemission studies of oxidation of hexagonal SiC surfaces and SiO2/SiC interfaces are reviewed and discussed. These investigations have focused on two main questions thought to have a significant effect on MOS device characteristics: the existence of carbon clusters or carbon-containing by-products and the existence of sub-oxides at the SiO2/SiC interface. The presentation is focused on Si-terminated surfaces of hexagonal n-type SiC(0001) crystals since they to date have been considered the most promising for device applications. The results reviewed show that no carbon clusters or carbon-containing by-product can be detected at the interface of in situ or ex situ grown samples with an oxide layer thickness larger than about 10 Å. Since the presence of carbon clusters was suggested in a recent scanning microscopy study it appears that they may exist, possibly depending on the sample preparation method used, but in such low concentrations that they are not detectable using photoemission. The presence of sub-oxides at the SiO2/SiC interface has been revealed in recorded Si 2p core level spectra by several groups. The results were not unanimous, however. The number of sub-oxides present and the shifts reported were different. The results of a recent study including also the Si 1s core level and Si KLL Auger transitions are therefore examined. These together with earlier Si 2p data show the presence of only one sub-oxide, assigned to Si1+ oxidation states, besides the fully developed SiO2 (Si4+). Possible reasons for the differences obtained earlier are discussed. That the sub-oxide is located at the interface is concluded from the relative intensity variations observed for the different components versus electron emission angle. An oxide thickness dependence of the SiO2 chemical shift in the core levels and Auger transitions is shown, similar to but smaller in magnitude than the thickness dependence revealed earlier for SiO2/Si. On cooled SiC(0001) substrates, adsorption of metastable molecular oxygen is suggested to occur in the initial oxidation stage like on the Si(111)-7 ? 7 surface. Oxidation results from the C-terminated surface and some preliminary results for the non-polar and surfaces are included and they show distinct differences both as regards the sub-oxides present and the amount of carbon-containing by-products at the interface in the initial oxidation stage compared to the Si-terminated SiC(0001) surface.

C Virojanadara; L I Johansson

2004-01-01T23:59:59.000Z

11

Transgenic Evaluation of Activated Mutant Alleles of SOS2 Reveals a Critical Requirement for Its Kinase Activity and  

E-Print Network [OSTI]

, Sevilla 41080, Spain In Arabidopsis thaliana, the calcium binding protein Salt Overly Sensitive3 (SOS3 of SOS2 can be constructed in vitro by changing Thr168 to Asp in the activation loop of the kinase is known to elicit a rapid increase in the free calcium concentration in the cytoplasm (Knight et al., 1997

Schumaker, Karen

12

A study of ZnxZryOz mixed oxides for direct conversion of ethanol...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

study of ZnxZryOz mixed oxides for direct conversion of ethanol to isobutene. A study of ZnxZryOz mixed oxides for direct conversion of ethanol to isobutene. Abstract: ZnxZryOz...

13

Combinatorial study of zinc tin oxide thin-film transistors  

SciTech Connect (OSTI)

Groups of thin-film transistors using a zinc tin oxide semiconductor layer have been fabricated via a combinatorial rf sputtering technique. The ZnO:SnO{sub 2} ratio of the film varies as a function of position on the sample, from pure ZnO to SnO{sub 2}, allowing for a study of zinc tin oxide transistor performance as a function of channel stoichiometry. The devices were found to have mobilities ranging from 2 to 12 cm{sup 2}/V s, with two peaks in mobility in devices at ZnO fractions of 0.80{+-}0.03 and 0.25{+-}0.05, and on/off ratios as high as 10{sup 7}. Transistors composed predominantly of SnO{sub 2} were found to exhibit light sensitivity which affected both the on/off ratios and threshold voltages of these devices.

McDowell, M. G.; Sanderson, R. J.; Hill, I. G. [Dalhousie University, Department of Physics, Halifax, Nova Scotia B3H 3J5 (Canada)

2008-01-07T23:59:59.000Z

14

Energy Based Methods in Wind Turbine Control CeSOS Highlights and AMOS Visions  

E-Print Network [OSTI]

Energy Based Methods in Wind Turbine Control CeSOS Highlights and AMOS Visions Morten D. Pedersen Passivity Based Control 5 Implementation Challenges Morten D. Pedersen (NTNU) June 7, 2013 2 / 26 #12 performed in wind tunnel using tower were not a b ogstad, P.E. Eriksen / Renewable Energy 50 (2013) 325e333

Nørvåg, Kjetil

15

Study on Degradation of Solid Oxide Fuel Cell With Pure Ni Anode Zhenjun Jiaoa  

E-Print Network [OSTI]

Study on Degradation of Solid Oxide Fuel Cell With Pure Ni Anode Zhenjun Jiaoa , Naoki Shikazonoa Solid oxide fuel cell (SOFC) has attracted more and more attentions in the last few decades hydrogen as a fuel and pure oxygen as an oxidant. Anode-reference static current method, with a current

Kasagi, Nobuhide

16

Conformation of Poly(ethylene oxide)-Hydroxybenzene Molecular Complexes Studied by Solid-State NMR  

E-Print Network [OSTI]

Conformation of Poly(ethylene oxide)-Hydroxybenzene Molecular Complexes Studied by Solid-State NMR February 16, 2000 ABSTRACT: The conformation of poly(ethylene oxide), PEO, in molecular complexes. Introduction Poly(ethylene oxide), PEO, is a relatively nonpolar polymer but contains ether oxygens

Hong, Mei

17

Oxidation of stepped Pt(111) studied by x-ray photoelectron spectroscopy and density functional theory  

SciTech Connect (OSTI)

In this comparative density functional theory and x-ray photoelectron spectroscopy study on the interaction of oxygen with stepped Pt(111) surfaces, we show that both the initial adsorption and oxidation occur at the steps rather than terraces. An equivalent behavior was observed for the oxide formation at higher chemical potentials, where, after the formation of a one-dimensional PtO{sub 2}-type oxide at the steps, similar oxide chains form on the (111) terraces, indicating the initial stages of bulk oxide formation.

Bandlow, Jochen; Kaghazchi, Payam; Jacob, Timo [Institut fuer Elektrochemie, Universitaet Ulm, Albert-Einstein-Allee 47, D-89069 Ulm (Germany); Papp, C.; Traenkenschuh, B.; Streber, R.; Lorenz, M. P. A.; Fuhrmann, T.; Steinrueck, H.-P. [Lehrstuhl fuer Physikalische Chemie II, Universitaet Erlangen-Nuernberg, Egerlandstr. 3, D-91058 Erlangen (Germany); Denecke, R. [Wilhelm-Ostwald-Institut fuer Physikalische und Theoretische Chemie, Universitaet Leipzig, Linnestr. 2, D-04103 Leipzig (Germany)

2011-05-01T23:59:59.000Z

18

Theoretical kinetic study of the low temperature oxidation of ethanol  

E-Print Network [OSTI]

In order to improve the understanding of the low temperature combustion of ethanol, high-level ab initio calculations were performed for elementary reactions involving hydroxyethylperoxy radicals. These radicals come from the addition of hydroxethyl radicals (?CH3CHOH and ?CH2CH2OH) on oxygen molecule. Unimolecular reactions involving hydroxyethylperoxy radicals and their radical products were studied at the CBS-QB3 level of theory. The results allowed to highlight the principal ways of decomposition of these radicals. Calculations of potential energy surfaces showed that the principal channels lead to the formation of HO2 radicals which can be considered, at low temperature, as slightly reactive. However, in the case of CH3CH(OOH)O? radicals, a route of decomposition yields H atom and formic peracid, which is a branching agent that can strongly enhance the reactivity of ethanol in low temperature oxidation. In addition to these analyses, high-pressure limit rate constants were derived in the temperature rang...

Fournet, René; Bounaceur, Roda; Molière, Michel

2009-01-01T23:59:59.000Z

19

A PROTEOMIC STUDY OF OXIDATIVE STRESS IN ALCOHOLIC LIVER DISEASE  

E-Print Network [OSTI]

to oxidative stress with tert-butyl hydroperoxide (TBHP) contained 17% less carbonylated proteins than the non-fat loaded control. Mass spectrometric analysis of carbonylated proteins indicated that known classical markers of protein carbonylation (e...

Newton, Billy W.

2010-01-16T23:59:59.000Z

20

Theoretical study of sequential oxidation of clusters of gallium oxide: Ga3On (n: 48)  

E-Print Network [OSTI]

as well as addition (and removal) of an electron leads to significant changes in the geometry oxide clusters, we found that the structural changes induced by addition and removal of an electron properties of neutral and ionized small GamOn (m,n = 1,2) clusters [2]. Addition of an electron introduced

Pandey, Ravi

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Influence of Ionic Surfactants on the Aggregation of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene Oxide) Block Copolymers Studied by Differential Scanning and  

E-Print Network [OSTI]

Influence of Ionic Surfactants on the Aggregation of Poly(Ethylene Oxide)-Poly(Propylene Oxide)-Poly(Ethylene copolymers of poly(ethylene oxide) and poly(propylene oxide), EOnPOmEOn, and the ionic surfactants sodium the aggregates of all three polymers. Introduction Water-soluble poly(ethylene oxide)-poly(propylene oxide)- poly(ethylene

Loh, Watson

22

Ferric oxide quantum dots in stable phosphate glass system and their magneto-optical study  

SciTech Connect (OSTI)

Graphical abstract: We report synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles (NCs) content on the optical and magneto-optical properties of the glasses. Faraday rotation of the glass nanocomposites was measured and showed variation in Verdet constant with concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and there is a threefold enhancement in the Verdet constant of ferric oxide quantum dot-glass nanocomposite. Highlights: ? We synthesize ferric oxide embedded low melting stable phosphate glass nanocomposite. ? Glasses doped with 0.25 and 2% ferric oxide show particle size in the range of 4–12 nm. ? The host phosphate glass itself shows fairly good Verdet constant (11.5°/T cm). ? Glasses doped with 0.25% ferric oxide show high Verdet constant (30.525°/T cm). ? The as synthesis glasses may have potential application in magneto optical devices. -- Abstract: Herein, we report the synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles content on the optical and magneto-optical properties of the glasses. The optical study clearly showed red shift in optical cut off with increasing ferric oxide concentration. The band gap of the host glass was observed to be 3.48 eV and it shifted to 3.14 eV after doping with ferric oxide. The glasses doped with 0.25 and 2% ferric oxide showed particle size of 4–6 nm and 8–12 nm, respectively. Faraday rotation of the glass nanocomposites was measured and showed variation in the Verdet constant as per increasing concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and threefold enhancement was observed in the Verdet constant of ferric oxide quantum dot-glass nanocomposite.

Garaje, Sunil N.; Apte, Sanjay K. [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)] [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India); Kumar, Ganpathy [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States)] [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States); Panmand, Rajendra P.; Naik, Sonali D. [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)] [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India); Mahajan, Satish M., E-mail: smahajan@tntech.edu [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States); Chand, Ramesh [Ministry of Communications and Information Technology, Department of Electronics and Information Technology (DeitY), Electronics Niketan, 6, CGO Complex, New Delhi 110003 (India)] [Ministry of Communications and Information Technology, Department of Electronics and Information Technology (DeitY), Electronics Niketan, 6, CGO Complex, New Delhi 110003 (India); Kale, Bharat B., E-mail: bbkale@cmet.gov.in [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)

2013-02-15T23:59:59.000Z

23

Comparative study of polyoxometalates and semiconductor metal oxides as catalyst. Photochemical oxidative degradation of thioethers  

SciTech Connect (OSTI)

The photochemical degradation of thioether substrates catalyzed by representative semiconductor metal oxides and sulfides (anatase TiO{sub 2}, SnO{sub 2}, cubic WO{sub 3}, and CdS) and photoredox-active early-transition-metal polyometalates (W{sub 10}O{sub 32}{sup 4{minus}}, PMo{sub 12}O{sub 40}{sup 3{minus}}, PW{sub 12}O{sub 40}{sup 3{minus}}, SiMo{sub 12}O{sub 40}{sup 4{minus}}, PV{sub 2}Mo{sub 10}O{sub 10}{sup 5{minus}}, and P{sub 2}W{sub 18}O{sub 62}{sup 6{minus}}) have been examined under both anaerobic and aerobic conditions. Under anaerobic conditions, all the semiconductors are completely ineffective at photochemically oxidizing or degrading the exemplary thioether substrate tetrahydrothiophene (THT) in the oxidatively resistant solvent acetonitrile. In contrast, all the homogeneous polyoxometalate systems under the same reaction condition, except the neutral tetra-n-butylammonium (Q) salt of PW{sub 12}O{sub 40}{sup 3{minus}}, are quite effective. The latter systems generate products derived from the carbon-based radical {alpha} to the sulfur atom and not sulfoxide or sulfone, the usual products of thioether oxidation by oxometal species. The rate for the most active anaerobic system, that involving the photochemical degradation of THT by Q{sub 4}W{sub 10}O{sub 32}, under optically dilute conditions, is first order in W{sub 10}O{sub 32} {sup 4{minus}} and light intensity and variable order in THT substrate. A rate law consistent with these data is given. Upon addition of O{sub 2}, TiO{sub 2} (with or without Pt(O)) becomes highly active, SnO{sub 2} becomes active, but WO{sub 3} and CdS remain inactive. Reactivity in thioether oxidation is dominated by the interactions of the semiconductors with O{sub 2} and O{sub 2}-derived intermediates; there is no correlation between reactivity and semiconductor band gap. Upon addition of O{sub 2}, all the polyoxometalate systems become more active. 29 refs., 4 figs., 3 tabs.

Chambers, R.C.; Hill, C.L. (Emory Univ., Atlanta, GA (United States))

1991-06-26T23:59:59.000Z

24

Salt-stone Oxidation Study: Leaching Method - 13092  

SciTech Connect (OSTI)

Cementitious waste forms can be designed to chemically stabilize selected contaminants, such as Tc{sup +7} and Cr{sup +6}, by chemically reduction to lower valance states, Tc{sup +4} and Cr{sup +3}, respectively, and precipitation of these species in alkaline media as low solubility solid phases. Data for oxidation of this type of cementitious waste form cured under field conditions as a function of time is required for predicting the performance of the waste form and disposal facility. The rate of oxidation (oxidation front advancement) is an important parameter for predicting performance because the solubilities of some radionuclide contaminants, e.g., technetium, are a function of the oxidation state. A non-radioactive experiment was designed for quantifying the oxidation front advancement using chromium, as an approximate redox-sensitive surrogate (Cr{sup +6} / Cr{sup +3}) for technetium (Tc{sup +7} / Tc{sup +4}). Nonradioactive cementitious waste forms were prepared in the laboratory and cured under both laboratory and 'field conditions'. Laboratory conditions were ambient temperature and sealed sample containers. Field conditions were approximated by curing samples in open containers which were placed inside a plastic container stored outdoors at SRS. The container had a lid and was instrumented with temperature and humidity probes. Sub-samples as thin as 0.2 mm were taken as a function of distance from the exposed surface of the as-cast sample. The sub-samples were leached and the leachates were analyzed for chromium, nitrate, nitrite and sodium. Nitrate, nitrite, and sodium concentrations were used to provide baseline data because these species are not chemically retained in the waste form matrix to any significant extent and are not redox sensitive. 'Effective' oxidation fronts for Cr were measured for samples containing 1000, 500 and 20 mg/kg Cr added as soluble sodium chromate, Na{sub 2}CrO{sub 4}. For a sample cured for 129 days under field conditions, leachable Cr (assumed to be the oxidized form, i.e., Cr{sup +6} was detected in the top 15 to 20 mm of the sample spiked with 1000 mg/kg Cr. Below about 20 mm, the Cr concentrations in leachates were below the detection limit (< 0.010 mg/L) which indicates that the oxidation as the result of exposure to air was limited to the top 20 mm of the sample after exposure for 129 days and that the bulk of the waste form was not affected, i.e., the Cr was stabilized and insoluble. For samples cured in the laboratory, leachable Cr was detected in the top 8 mm of the Cr 1000 sample cured in the laboratory for 37 days. Between 8 and 14 mm, the concentration Cr in the leachate dropped by a factor of about 20 to just above the detection limit. These depth of penetration results indicate that the rate of advancement of the oxidation front for samples spiked with 1000 mg/kg Cr cured under 'field conditions' for 129 days is less than that for the sample cured in the laboratory for 37 days, i.e., 0.156 and 0.216 mm/day, respectively. Additional data are presented for samples spiked with 500 and 20 mg/kg Cr. In summary, cementitious waste forms are porous solids with a network of interconnected pores ranging in diameter from 10 E-10 m to greater than a few mm. The oxidation process is assumed to occur as the result of oxygen transport through the interconnected porosity which may be filled with air, aqueous salt solution, or both. Upon oxidation, the Cr becomes soluble and can be transported in solution through aqueous pore fluid or leachate. (authors)

Langton, C.A.; Stefanko, D.B.; Burns, H.H. [Savannah River National Laboratory, Savannah River Remediation, LLC, Savannah River Site, Aiken, SC 29808 (United States)] [Savannah River National Laboratory, Savannah River Remediation, LLC, Savannah River Site, Aiken, SC 29808 (United States)

2013-07-01T23:59:59.000Z

25

Capacitance studies of cobalt oxide films formed via electrochemical precipitation  

E-Print Network [OSTI]

prepared by electrochemically precipitating the hydroxide and heating it in air to form Co3O4 the need to identify more suitable materials. One promising route is the use of transi- tion metal oxides to batteries, are referred to as Faradaic or pseudocapacitors. However, the high cost of these materials has

Weidner, John W.

26

Mechanistic Studies of Methanol Oxidation to Formaldehyde on Isolated Vanadate Sites Supported on MCM-48  

E-Print Network [OSTI]

. Methanol reacts reversibly, at a ratio of approximately 1 methanol per V, with one V-O-Si to produce both V-state reaction conditions, CH2O is produced as the dominant product of methanol oxidation at temperatures belowMechanistic Studies of Methanol Oxidation to Formaldehyde on Isolated Vanadate Sites Supported

Bell, Alexis T.

27

Density Functional Theory Studies of the Structure Sensitivity of Ethanol Oxidation on Palladium Surfaces  

E-Print Network [OSTI]

Density Functional Theory Studies of the Structure Sensitivity of Ethanol Oxidation on PalladiumVised Manuscript ReceiVed: May 04, 2010 In this work, the adsorption behaviors and oxidation mechanisms of ethanol palladium surfaces, the adsorption behaviors, and the first step dehydrogenation of ethanol, it is found

Zhao, Tianshou

28

Studies on supported metal oxide-oxide support interactions (an incorporation model)  

SciTech Connect (OSTI)

XRD, XPS, SSIMS, LRS, and FT-IR are used to explore the valency, composition and structure of the dispersed metal oxide species on supports with different structures, i.e., on ceria and {gamma}-alumina. The results indicated that the dispersion of various ionic compounds are proceeded by the incorporation of the metal cations into the surface vacant sites on the support provided that the loading amounts of the compounds are not higher than their dispersion capacities. The key factors determining the dispersion capacities of the ionic compounds are: (1) the surface structure of the support which determines the size and number of the vacant sites available. (2) the valency of the dispersed ionic compound and the size of the anion, from which the shielding effect of the capping anion(s) can be evaluated, and (3) the sizes of the dispersed cations and the vacant sites on the surface, from which the sites can be used for incorporation can be identified. The Quantitative results deduced from the incorporation model and from the independent experiments are consistent, providing further evidence that the model captures the essentials of the interactions between the dispersed metal oxide and support.

Yi Chen; Lin Dong; Y.S. Jin; Bing Xu; Weijie Ji [Nanjing Univ. (China)

1996-12-31T23:59:59.000Z

29

A kinetics study of the atmospheric pressure CVD reaction of silane and nitrous oxide  

SciTech Connect (OSTI)

A mechanistic study of oxide deposition from silane and nitrous oxide between 495{sup 0}C and 690{sup 0}C was performed in a laminar flow, cool wall reactor. Results indicate the existence of two distinct chemical pathways. At high nitrous oxide concentrations, the deposition reaction is dominated by radical chain chemistry initiated by the decomposition of N/sub 2/O. At lower N/sub 2/O concentrations, the decomposition of silane to form silylene (SiH/sub 2/) initiates the deposition. Studies of the reaction of disilane and nitrous oxide confirmed the role of SiH/sub 2/ in the deposition. Reactions involving SiH/sub 2/ are used to explain the observed growth of sub-stoichiometric oxides under low N/sub 2/O conditions.

Chapple-Sokol, J.D.; Giunta, C.J.; Gordon, R.G. (Harvard Univ., Cambridge, MA (USA). Dept. of Chemistry)

1989-10-01T23:59:59.000Z

30

A Reactive Oxide Overlayer on Rh Nanoparticles during CO Oxidation and Its Size Dependence Studied by in Situ Ambient Pressure XPS  

SciTech Connect (OSTI)

CO oxidation is one of the most studied heterogeneous reactions, being scientifically and industrially important, particularly for removal of CO from exhaust streams and preferential oxidation for hydrogen purification in fuel cell applications. The precious metals Ru, Rh, Pd, Pt, and Au are most commonly used for this reaction because of their high activity and stability. Despite the wealth of experimental and theoretical data, it remains unclear what is the active surface for CO oxidation under catalytic conditions for these metals. In this communication, we utilize in situ synchrotron ambient pressure X-ray photoelectron spectroscopy (APXPS) to monitor the oxidation state at the surface of Rh nanoparticles during CO oxidation and demonstrate that the active catalyst is a surface oxide, the formation of which is dependent on particle size. The amount of oxide formed and the reaction rate both increase with decreasing particle size.

Grass, Michael E.; Zhang, Yawen; Butcher, Derek R.; Park, Jeong Y.; Li, Yimin; Bluhm, Hendrik; Bratlie, Kaitlin M.; Zhang, Tianfu; Somorjai, Gabor A.

2008-09-15T23:59:59.000Z

31

Femtosecond pump-probe studies of reduced graphene oxide thin films  

E-Print Network [OSTI]

The dynamics of photocarriers in reduced graphene oxide thin films is studied by using ultrafast pump-probe spectroscopy. Time dependent differential transmissions are measured with sample temperatures ranging from 9 to 300 K. At each sample...

Ruzicka, Brian Andrew; Werake, Lalani Kumari; Zhao, Hui; Wang, Shuai; Loh, Kian Ping

2010-04-01T23:59:59.000Z

32

Synchrotron x-ray reflectivity study of oxidation/passivation of copper and silicon.  

SciTech Connect (OSTI)

Synchrotron x-ray-scattering technique studies of copper and silicon electrochemical interfaces are reported. These two examples illustrate the application of synchrotron x-ray techniques for oxidation, passivation, and dissolution of metals and semiconductors.

Chu, Y.; Nagy, Z.; Parkhutik, V.; You, H.

1999-07-21T23:59:59.000Z

33

Solid-State NMR Spectroscopic Study of Phosphate Sorption Mechanisms on Aluminum (Hydr)oxides  

E-Print Network [OSTI]

Solid-State NMR Spectroscopic Study of Phosphate Sorption Mechanisms on Aluminum (Hydr)oxides Wei the mechanism of phosphate sorption on aluminum hydroxides under different environ- mental conditions, including

Sparks, Donald L.

34

A study on the oxidation characteristics of cast irons containing aluminum  

SciTech Connect (OSTI)

Isothermal-oxidation characteristics of cast irons containing aluminum (5-15% Al) from 700 to 1000{degrees}C in air have been studied. In addition to mass-gain measurements, the morphology and composition of the oxide scales have been examined by SEM-EDX system and XRD analysis. A normal Fe-5Al-C alloy does not develop protective, adherent scales. Even the addition of misch metal and calcium silicide to such an alloy does not improve its oxidation resistance. But aluminum cast iron develops considerable oxidation resistance only when a sufficient quantity of silicon is also present in the alloy. Treatment of the alloy with misch metal and calcium silicide together assists in protective scale formation. Among the alloys investigated Fe-15Al-Si-C treated with misch metal and calcium silicide shows minimum oxidation at 1000{degrees}C.

Ghosh, S.; Prodhan, A. [National Metallurigical Laboratory, Jamshedpur (India); Mohanty, O.N. [Tata Steel, Jamshedpur (India)] [and others

1996-02-01T23:59:59.000Z

35

SRF Materials: Fundamental studies of interfacial oxidation chemistry of niobium  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

FNAL/UC Collaboration meeting 27 Nov 2007 FNAL/UC Collaboration meeting 27 Nov 2007 SRF Materials: Niobium Oxidation, Control A New Explanation for Baking! Pellin 1 , Zasadzinski 2 , Prolier 1,2 , Moore 3 , Norem 3 , Cooley 4 1. Materials Science Division, ANL 2. Department of Biological, Chemical and Physical Sciences, IIT 3. High Energy Physics, ANL 4. Technical Division, FNAL ANL-LDRD ANL/FNAL/UC Collaboration meeting 27 Nov 2007 XPS a Surface Probe of Nb Oxidation Nb 2 O 5 Nb NbO x Dielectric Nb 2 O 5 Nb 2 O 5-δ , NbO 2-δ are magnetic NbO x (0.2 < x < 2),metallic NbO x precipitates (0.02 < x < 0.2) Scattering off magnetic interfaces or precipitates gives rise to Shiba states inside the gap. These cause dissipation (lowering Q). Nb samples supplied by FNAL! ANL/FNAL/UC Collaboration meeting 27 Nov 2007 Point Contact Tunneling -

36

Structure of crystalline oxide ceramics studied by phonon spectroscopy  

SciTech Connect (OSTI)

This paper describes a method for gaining detailed insight into the structure and phonon spectrum of polycrystalline oxide ceramics. We examine how the diffusion coefficient of subterahertz phonons is related to the properties of a system of grain boundaries and to the grain size and structure and demonstrate that the temperature dependence of the phonon diffusion coefficient at liquid-helium temperatures is determined by the spectral properties of the intergranular layer, which allows one to estimate the volumeaveraged intergranular layer thickness and acoustic impedance. We also analyse the effect of plastic deformation via twinning on the formation of the structure of grains and intergranular layers, which determine the thermophysical, acoustic and optical properties of ceramic materials. (extreme light fields and their applications)

Kaminskii, Alexandr A; Taranov, A V; Khazanov, E N

2013-03-31T23:59:59.000Z

37

The oxidation of aluminum at high temperature studied by Thermogravimetric Analysis and Differential Scanning Calorimetry.  

SciTech Connect (OSTI)

The oxidation in air of high-purity Al foil was studied as a function of temperature using Thermogravimetric Analysis with Differential Scanning Calorimetry (TGA/DSC). The rate and/or extent of oxidation was found to be a non-linear function of the temperature. Between 650 and 750 %C2%B0C very little oxidation took place; at 850 %C2%B0C oxidation occurred after an induction period, while at 950 %C2%B0C oxidation occurred without an induction period. At oxidation temperatures between 1050 and 1150 %C2%B0C rapid passivation of the surface of the aluminum foil occurred, while at 1250 %C2%B0C and above, an initial rapid mass increase was observed, followed by a more gradual increase in mass. The initial rapid increase was accompanied by a significant exotherm. Cross-sections of oxidized specimens were characterized by scanning electron microscopy (SEM); the observed alumina skin thicknesses correlated qualitatively with the observed mass increases.

Coker, Eric Nicholas

2013-10-01T23:59:59.000Z

38

Transpiring wall supercritical water oxidation reactor salt deposition studies  

SciTech Connect (OSTI)

Sandia National Laboratories has teamed with Foster Wheeler Development Corp. and GenCorp, Aerojet to develop and evaluate a new supercritical water oxidation reactor design using a transpiring wall liner. In the design, pure water is injected through small pores in the liner wall to form a protective boundary layer that inhibits salt deposition and corrosion, effects that interfere with system performance. The concept was tested at Sandia on a laboratory-scale transpiring wall reactor that is a 1/4 scale model of a prototype plant being designed for the Army to destroy colored smoke and dye at Pine Bluff Arsenal in Arkansas. During the tests, a single-phase pressurized solution of sodium sulfate (Na{sub 2}SO{sub 4}) was heated to supercritical conditions, causing the salt to precipitate out as a fine solid. On-line diagnostics and post-test observation allowed us to characterize reactor performance at different flow and temperature conditions. Tests with and without the protective boundary layer demonstrated that wall transpiration provides significant protection against salt deposition. Confirmation tests were run with one of the dyes that will be processed in the Pine Bluff facility. The experimental techniques, results, and conclusions are discussed.

Haroldsen, B.L.; Mills, B.E.; Ariizumi, D.Y.; Brown, B.G. [and others

1996-09-01T23:59:59.000Z

39

Muon Spin Relaxation Study of Spinel Lithium Manganese Oxides  

Science Journals Connector (OSTI)

Muons can be implanted into any material, and the direction of the muon spin at the instant of decay (?+ ? e+ + ?e + ???, lifetime = 2.179 ?s) provides information on the dynamics of the muon during its lifetime and on the static and fluctuating magnetic fields from neighboring nuclear and atomic moments. ... On the other hand, the shape of the H+-MnO2 spectrum at 100 K shows two Gaussian components, which indicates the existence of at least two different depolarization rates that can be due to muons at two different muon sites. ... Therefore, these results indicate that the temperature for onset of Li+ ion diffusion decreases with an increase in the amount of lithium in the spinel manganese oxide, which is not incompatible with a higher Li+ diffusion coefficient on LiMn2O4 than on Li1.33Mn1.67O4 found from NMR experiments,21 since NMR data will average over all Li nuclei whereas muons only interact with those Li nearest to the muon. ...

María J. Ariza; Deborah J. Jones; Jacques Rozière; James S. Lord; Didier Ravot

2003-05-28T23:59:59.000Z

40

Infrared spectroscopic study of the adsorption of carbon monoxide on silica-supported copper oxide  

SciTech Connect (OSTI)

Adsorption of carbon monoxide at room temperature (0.1 to 50 Torr) on silica-supported copper oxide was studied by infrared spectroscopy. Catalysts were prepared by deposition-precipitation or impregnation. After calcination two types of adsorbed CO were identified showing absorption bands at 2136 +- 3 and 2204 +- 1 cm/sup -1/, which are ascribed to CO adsorbed on copper(II) oxide and on isolated copper(II) ions in the silica surface, respectively. Reduction and reoxidation removed the band at 2204 cm/sup -1/ with all samples and raised the intensity of the 2136-cm/sup -1/ band with the precipitated catalysts but not with the impregnation catalyst. Evidence is brought forward that the isolated copper ions are mobilized during reduction and generate new copper (oxide) surface. The change in background transmission of the samples could be used to obtain further information about the interaction of O/sub 2/ and CO with copper oxide.

De Jong, K.P.; Geus, J.W.; Joziasse, J.

1980-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Polycrystalline oxides formation during transient oxidation of (001) Cu-Ni binary alloys studied by in situ TEM and XRD.  

SciTech Connect (OSTI)

The nucleation and growth of Cu{sub 2}O and NiO islands due to oxidation of Cu{sub x}Ni{sub 1-x} (001) films were monitored, at various temperatures, by in situ ultra-high vacuum (UHV) transmission electron microscopy (TEM) and in situ synchrotron X-ray diffraction (XRD). In remarkable contrast to our previous observations of Cu and Cu-Au oxidation, irregular-shaped polycrystalline oxide islands formed with respect to the Cu-Ni alloy film, and an unusual second oxide nucleation stage was noted. In situ XRD experiments revealed that NiO formed first epitaxially, then other orientations appeared, and finally polycrystalline Cu{sub 2}O developed as the oxidation pressure was increased. The segregation of Ni and Cu towards or away, respectively, from the alloy surface during oxidation could disrupt the surface and cause polycrystalline oxide formation.

Yang, J. C.; Li, Z. Q.; Sun, L.; Zhou, G. W.; Eastman, J. A.; Fong, D. D.; Fuoss, P. H.; Baldo, P. M.; Rehn, L. E.; Thompson, L. J.; Materials Science Division; Univ.of Pittsburgh; State Univ. of New York at Binghamton

2009-01-01T23:59:59.000Z

42

Structural, electronic, mechanical, and dynamical properties of graphene oxides: A first principles study  

SciTech Connect (OSTI)

We report the results of a theoretical study on the structural, electronic, mechanical, and vibrational properties of some graphene oxide models (GDO, a-GMO, z-GMO, ep-GMO and mix-GMO) at ambient pressure. The calculations are based on the ab-initio plane-wave pseudo potential density functional theory, within the generalized gradient approximations for the exchange and correlation functional. The calculated values of lattice parameters, bulk modulus, and its first order pressure derivative are in good agreement with other reports. A linear response approach to the density functional theory is used to derive the phonon frequencies. We discuss the contribution of the phonons in the dynamical stability of graphene oxides and detailed analysis of zone centre phonon modes in all the above mentioned models. Our study demonstrates a wide range of energy gap available in the considered models of graphene oxide and hence the possibility of their use in nanodevices.

Dabhi, Shweta D. [Department of Physics, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar 364001 (India); Gupta, Sanjay D. [V. B. Institute of Science, Department of Physics, C. U. Shah University, Wadhwan City - 363030, Surendranagar (India); Jha, Prafulla K., E-mail: prafullaj@yahoo.com [Department of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara-390002 (India)

2014-05-28T23:59:59.000Z

43

Oxidation states study of nickel in solid oxide fuel cell anode using x-ray full-field spectroscopic nano-tomography  

Science Journals Connector (OSTI)

Identifying the chemical state and coupling with morphological information in three dimensions are of great interest in energy storage materials which typically involve reduction-oxidation cycling and structural evolution. Here we apply x-ray nano-tomography with multiple x-ray energies to study oxidation states of nickel(Ni) and nickel oxide phases in Ni-yttria-stabilized zirconia (YSZ) a typical anodematerial of solid oxide fuel cells(SOFC). We present a method to quantitatively identify the nickel-based oxides from Ni-YSZ anodecomposite and obtain chemical mapping as well as associated microstructures at nanometer scale in three dimensions. NiO particles manually placed on a Ni-YSZ compositeanode were used for validation of the method while no nickel oxides were found to be present within the electrode structure as remnants of the cell fabrication process. The application of the method can be widely applied to energy storage materials including SOFCs Li-ion batteries and supercapacitors as well as other systems for oxidation and reduction study.

Yu-chen Karen Chen-Wiegart; William M. Harris; Jeffrey J. Lombardo; Wilson K. S. Chiu; Jun Wang

2012-01-01T23:59:59.000Z

44

Fundamental studies of stress distributions and stress relaxation in oxide scales on high temperature alloys. [Final progress report  

SciTech Connect (OSTI)

This report summarizes a three-year study of stresses arising in the oxide scale and underlying metal during high temperature oxidation and of scale cracking. In-situ XRD was developed to measure strains during oxidation over 1000{degrees}C on pure metals. Acoustic emission was used to observe scale fracture during isothermal oxidation and cooling, and statistical analysis was used to infer mechanical aspects of cracking. A microscratch technique was used to measure the fracture toughness of scale/metal interface. A theoretical model was evaluated for the development and relaxation of stresses in scale and metal substrate during oxidation.

Shores, D.A.; Stout, J.H.; Gerberich, W.W.

1993-06-01T23:59:59.000Z

45

An experimental and detailed chemical kinetic modelling study of 2methyl furan oxidation  

E-Print Network [OSTI]

platform chemical 5hydroxymethylfurfural now a possibility [4], [5], [6] and [7]. 25DMF offers significantAn experimental and detailed chemical kinetic modelling study of 2methyl furan oxidation.55­1.65, initial temperatures of 298­398 K and atmospheric pressure. A detailed chemical kinetic mechanism

Paris-Sud XI, Université de

46

indirect study, coal was oxidatively de-graded with sodium dichromate and the  

E-Print Network [OSTI]

Cleaning Technology (Noyes Data Corporation, Park Ridge, N.J., 1981). 10. Z. Hussain, E. Umbach, D. Aindirect study, coal was oxidatively de- graded with sodium dichromate and the esterified products- vestigators concluded (17, p. 380) that "thiophene derivatives must be indige- nous to coal." The direct XANES

Howat, Ian M.

47

Rare earth element sorption onto hydrous manganese oxide A modeling study  

E-Print Network [OSTI]

element sorption onto hydrous manganese oxide A modeling study Olivier Pourret1* and Mélanie Davranche2 1 models due to the lack of a comprehensive set of sorption reactions consistent with a given surface complexation model (SCM), as well as discrepancies between published sorption data and predictions using

Paris-Sud XI, Université de

48

A Preliminary Study of Oxidation of Lignin from Rubber Wood to Vanillin in Ionic Liquid Medium  

E-Print Network [OSTI]

In this study, lignin was oxidised to vanillin by means of oxygen in ionic liquid (1,3-dimethylimidazolium methylsulphate) medium. The parameters of the oxidation reaction that have been investigated were the following: concentration of oxygen (5, 10, 15 and 20 ft3 h-1), reaction time (2, 4, 6, 8 and 10 h) and reaction temperature (25, 40, 60, 80 and 100{\\deg}C). The Fourier transform infrared spectroscopy, high performance liquid chromatography and ultraviolet-visible analyses were used to characterise the product. The results revealed vanillin as the product obtained via the oxidation reaction. The optimum parameters of vanillin production were 20 ft3 h-1 of oxygen for 10 h at 100{\\deg}C. In conclusion, 1,3-dimethylimidazolium methylsulphate could be used as an oxidation reaction medium for the production of vanillin from rubber wood lignin.

Shamsuri, A A

2013-01-01T23:59:59.000Z

49

X-ray Photoelectron Spectroscopy Studies of Oxidized and Reduced CeO?(111) Surfaces  

SciTech Connect (OSTI)

We have studied the electronic structure of oxidized and reduced CeO? (111) surfaces using X-ray photoelectron spectroscopy (XPS). The 50 nm thick Co?(111) film was grown on a YSZ(111) substrate using oxygen plasma assisted molecular beam epitaxy (OPA-MBE). This film has been characterized using in-situ RHEED (reflection high energy electron diffraction) and ex-situ XRD (X-ray diffraction), HRTEM (high resolution transmission electron microscopy) and RBS (Rutherford backscattering spectroscopy). The lattice mismatch between CeO?(111) and YSZ(111) is less than 5% and yields a flat surface that is comprised of an equivalent number of Ce?? and O?? ions. Oxidation with O? at 773 K under UHV conditions was sufficient to fully oxidize the CeO?(111). Surface reduction was carried out by annealing in UHV at 973 K.

Engelhard, Mark H.; Azad, Samina; Peden, Charles HF; Thevuthasan, Suntharampillai

2004-12-01T23:59:59.000Z

50

Schedule optimization study implementation plan  

SciTech Connect (OSTI)

This Implementation Plan is intended to provide a basis for improvements in the conduct of the Environmental Restoration (ER) Program at Hanford. The Plan is based on the findings of the Schedule Optimization Study (SOS) team which was convened for two weeks in September 1992 at the request of the U.S. Department of Energy (DOE) Richland Operations Office (RL). The need for the study arose out of a schedule dispute regarding the submission of the 1100-EM-1 Operable Unit (OU) Remedial Investigation/Feasibility Study (RI/FS) Work Plan. The SOS team was comprised of independent professionals from other federal agencies and the private sector experienced in environmental restoration within the federal system. The objective of the team was to examine reasons for the lengthy RI/FS process and recommend ways to expedite it. The SOS team issued their Final Report in December 1992. The report found the most serious impediments to cleanup relate to a series of management and policy issues which are within the control of the three parties managing and monitoring Hanford -- the DOE, U.S. Environmental Protection Agency (EPA), and the State of Washington Department of Ecology (Ecology). The SOS Report identified the following eight cross-cutting issues as the root of major impediments to the Hanford Site cleanup. Each of these eight issues is quoted from the SOS Report followed by a brief, general description of the proposed approach being developed.

Not Available

1993-11-01T23:59:59.000Z

51

In situ kinetics study of the accelerated ageing of poly(ethylene oxide) by photoDSC  

E-Print Network [OSTI]

1 In situ kinetics study of the accelerated ageing of poly(ethylene oxide) by photoDSC F. Fraisse1 photo and thermo degradation. This paper presents a kinetic study of thermo and photoageing of poly(ethylene such as PEO. Experimental Several samples of poly(ethylene oxide) were used. The samples with a molecular

Paris-Sud XI, Université de

52

Fuel instability studies; Liquid phase oxidation of tetrahydrothiophene by tert-butyl hydroperoxide  

SciTech Connect (OSTI)

The reactions that lead to fuel instability are the subject of conflicting reports in the literature. Confusion results from the difficulty in relating differences in fuel composition, temperature, surface effects and dissolved oxygen content that comprise the multitude of reported studies. Model studies offer a means by chic the mechanism of an individual reaction can be related to a simple system and then extended to the more complex fuel media. This paper reports a model oxidation study of a species, t-butyl hydroperoxide under mild reaction conditions, 120{degrees}C, in a tetradecane model fuel. The major oxidation product was tetrahydrothiophene sulfoxide from the sulfide and t-butanol from the hydroperoxide. The complete suite of products is reported.

Mushrush, G.W.; Pellenbarg, R.E.; Hazlett, R.N.; Morris, R.E.; Hardy, D.R. (Fuels Section, Code 6180, Naval Research Lab., Washington, DC (US))

1991-01-01T23:59:59.000Z

53

Surface Complexation of Pb(II) on Amorphous Iron Oxide and Manganese Oxide: Spectroscopic and Time Studies  

SciTech Connect (OSTI)

Hydrous Fe and Mn oxides (HFO and HMO) are important sinks for heavy metals and Pb(II) is one of the more prevalent metal contaminants in the environment. In this work, Pb(II) sorption to HFO (Fe{sub 2}O{sub 3}{center_dot}nH{sub 2}O, n=1-3) and HMO (MnO{sub 2}) surfaces has been studied with EXAFS: mononuclear bidentate surface complexes were observed on FeO{sub 6} (MnO{sub 6}) octahedra with Pb{single_bond}O distance of 2.25-2.35 Angstroms and Pb{single_bond}Fe(Mn) distances of 3.29-3.36 (3.65-3.76) Angstroms. These surface complexes were invariant of pH 5 and 6, ionic strength 2.8x10{sup -3} to 1.5x10{sup -2}, loading 2.03x10{sup -4} to 9.1 x 10{sup -3} mol Pb/g, and reaction time up to 21 months. EXAFS data at the Fe K-edge revealed that freshly precipitated HFO exhibits short-range order; the sorbed Pb(II) ions do not substitute for Fe but may inhibit crystallization of HFO. Pb(II) sorbed to HFO through a rapid initial uptake ({approx}77%) followed by a slow intraparticle diffusion step ({approx}23%) resulting in a surface diffusivity of 2.5x10{sup -15} cm{sup 2}/s. Results from this study suggest that mechanistic investigations provide a solid basis for successful adsorption modeling and that inclusion of intraparticle surface diffusion may lead to improved geochemical transport depiction.

Xu,Y.; Boonfueng, T.; Axe, L.; Maeng, S.; Tyson, T.

2006-01-01T23:59:59.000Z

54

CHEMISTRY OF SO{sub 2} ON MODEL METAL AND OXIDE CATALYSTS: PHOTOEMISSION AND XANES STUDIES  

SciTech Connect (OSTI)

High-resolution synchrotron based photoemission and x-ray absorption spectroscopy have been used to study the interaction of SO{sub 2} with a series of metals and oxides. The chemistry of SO{sub 2} on metal surfaces is rich. At low coverages, the molecule fully decomposes into atomic S and O. At large coverages, the formation of SO{sub 3} and SO{sub 4} takes place. The following sequence was found for the reactivity of the metals towards SO{sub 2}: Pt {approx} Rh < Ru < Mo << Zn, Sn, Cs. Alloying can be useful for reducing the chemical affinity of a metal for SO{sub 2} and controlling S poisoning. Pd atoms bonded to Rh and Pt atoms bonded to Sn interact weakly with SO{sub 2}. In general, SO{sub 2} mainly reacts with the O centers of metal oxides. SO{sub 4} is formed on CeO{sub 2} and SO{sub 3} on ZnO. On these systems there is no decomposition of SO{sub 2}. Dissociation of the molecule is observed after introducing a large amount of Ce{sup 3+} sites in ceria, or after depositing Cu or alkali metals on the oxide surfaces. These promote the catalytic activity of the oxides during the destruction of SO{sub 2}.

RODRIGUEZ,J.A.; JIRSAK,T.; CHATURVEDI,S.; HRBEK,J.; FREITAG,A.; LARESE,J.Z.

2000-07-09T23:59:59.000Z

55

Transgenic evaluation of activated mutant alleles of SOS2 reveals a critical requirement for its kinase activity and C-terminal regulatory domain for salt tolerance in Arabidopsis thaliana  

DOE Patents [OSTI]

The present invention provides a method of increasing salt tolerance in a plant by overexpressing a gene encoding a mutant SOS2 protein in at least one cell type in the plant. The present invention also provides for transgenic plants expressing the mutant SOS2 proteins.

Zhu, Jian-Kang (Riverside, CA); Quintero-Toscano, Francisco Javier (Sevilla, ES); Pardo-Prieto, Jose Manuel (Sevilla, ES); Qiu, Quansheng (Urbana, IL); Schumaker, Karen Sue (Tucson, AZ); Ohta, Masaru (Tsukuba, JP); Zhang, Changqing (Tucson, AZ); Guo, Yan (Beijing, CN)

2007-09-04T23:59:59.000Z

56

Oxidation of Propane by Doped Nickel Oxides  

Science Journals Connector (OSTI)

... present study, however, indicate that in the absence of excess oxygen, direct oxidation of propane by the oxide lattice can occur.

D. W. McKEE

1964-04-11T23:59:59.000Z

57

A quantum chemical study of nitric oxide reduction by ammonia (SCR reaction) on V2O5 catalyst surface  

E-Print Network [OSTI]

A quantum chemical study of nitric oxide reduction by ammonia (SCR reaction) on V2O5 catalyst for the selective catalytic reduction (SCR) of nitric oxide by ammonia on (0 1 0) V2O5 surface represented by a V2O9/6-31G** level. The computations indicated that SCR reaction consisted of three main parts

Senkan, Selim M.

58

Oxidation studies of CrAlON nanolayered coatings on steel plates...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

cost and high-temperature corrosion resistance for bipolar interconnect plates in solid oxide fuel cell stacks have directed attention to the use of metal plates with oxidation...

59

An experimental and kinetic modelling study of the oxidation of the four isomers of butanol  

E-Print Network [OSTI]

Butanol, an alcohol which can be produced from biomass sources, has received recent interest as an alternative to gasoline for use in spark ignition engines and as a possible blending compound with fossil diesel or biodiesel. Therefore, the autoignition of the four isomers of butanol (1-butanol, 2-butanol, iso-butanol, and tert-butanol) has been experimentally studied at high temperatures in a shock tube and a kinetic mechanism for description of their high-temperature oxidation has been developed. Ignition delay times for butanol/oxygen/argon mixtures have been measured behind reflected shock waves at temperatures and pressures ranging from approximately 1200 to 1800 K and 1 to 4 bar. Electronically excited OH emission and pressure measurements were used to determine ignition delay times. A detailed kinetic mechanism has been developed to describe the oxidation of the butanol isomers and validated by comparison to the shock tube measurements. Reaction flux and sensitivity analysis indicate that the consumpti...

Moss, J T; Oehlschlaeger, M A; Biet, Joffrey; Warth, Valérie; Glaude, Pierre-Alexandre; Battin-Leclerc, Frédérique; 10.1021/jp806464p

2008-01-01T23:59:59.000Z

60

Copolymerization study of 1,2- and 1,4-cyclohexene oxide  

E-Print Network [OSTI]

soluble in this 'solvent blend, Better resolution of the tertiary proton resonance was obtained by running the copolymers in benzene. Copolymers g 0 through g 9 were run in benzene (See Table 2), Copolymers g 1, g 2 and 4 3 fractionated in benzene... spectrum has been published on the homo- polymer of 1, 4 -cyclohexene oxide, Partial] y deuterated 22 cis and trans 1, 4-cyclohexanediol have been studied by NNR. 36 It has been pointed out in the literature that equatorial protons are shifted further...

Glaesmann, Orville Lee

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Studies on transparent spinel magnesium indium oxide thin films prepared by chemical spray pyrolysis  

Science Journals Connector (OSTI)

Ternary semiconducting oxide compound magnesium indium oxide films (MgIn2O4), manifesting high transparency were prepared by metal organic chemical spray pyrolysis technique. Precursors prepared for various cationic ratios of Mg/In = 0.35, 0.40, 0.45 and 0.50 were thermally sprayed onto quartz substrates, decomposed at 450 °C and the spinel phase evolution was studied. X-ray diffraction, Rutherford backscattering and X-ray photoelectron spectroscopy studies have been conducted to confirm the formation of single-phase MgIn2O4 films with Mg/In ratio 0.50. From optical transmission studies, the observed optical band gaps varied from 3.18 to 3.86 eV (0.35 < Mg/In < 0.5). The electrical conductivity variations of these films were measured in the temperature range between 30 and 150 °C by four-probe technique (34.07–1.44 × 10? 5 S cm? 1) and the Hall coefficient showed n-type electrical conduction and high carrier concentration (0.16 × 1020–0.89 × 17 cm? 3).

A. Moses Ezhil Raj; V. Senthilkumar; V. Swaminathan; Joachim Wollschläger; M. Suendorf; M. Neumann; M. Jayachandran; C. Sanjeeviraja

2008-01-01T23:59:59.000Z

62

Reactivity of biogenic manganese oxide for metal sequestration and photochemistry: Computational solid state physics study  

SciTech Connect (OSTI)

Many microbes, including both bacteria and fungi, produce manganese (Mn) oxides by oxidizing soluble Mn(II) to form insoluble Mn(IV) oxide minerals, a kinetically much faster process than abiotic oxidation. These biogenic Mn oxides drive the Mn cycle, coupling it with diverse biogeochemical cycles and determining the bioavailability of environmental contaminants, mainly through strong adsorption and redox reactions. This mini review introduces recent findings based on quantum mechanical density functional theory that reveal the detailed mechanisms of toxic metal adsorption at Mn oxide surfaces and the remarkable role of Mn vacancies in the photochemistry of these minerals.

Kwon, K.D.; Sposito, G.

2010-02-01T23:59:59.000Z

63

Structural transition in rare earth doped zirconium oxide: A positron annihilation study  

SciTech Connect (OSTI)

Graphical abstract: New microstructural analysis and phase transition of rare earth doped mixed oxide compounds such as: Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where x = 0.0 ? x ? 2.0) that are potentially useful as solid oxide fuels, ionic conductors, optoelectronic materials and most importantly as radiation resistant host for high level rad-waste disposal, structural transition in the system is reported through positron annihilation spectroscopy as there is an indication in the X-ray diffraction analysis. Highlights: ? Zirconium oxide material doped with rare earth ions. ? The method of positron annihilation spectroscopy suggests a phase transition in the system. ? The crystal structure transformation from pure pyrochlore to defect fluorite type of structure is shown by X-ray diffraction results. -- Abstract: A series of compounds with the general composition Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where 0 ? x ? 2.0) were synthesized by chemical route and characterized by powder X-ray diffraction (XRD) analysis. The rare earth ion namely Sm{sup +3} in the compound was gradually replaced with another smaller and heavier ion, Dy{sup +3} of the 4f series, there by resulting in order–disorder structural transition, which has been studied by positron annihilation lifetime and Doppler broadening spectroscopy. This study reveals the subtle electronic micro environmental changes in the pyrochlore lattice (prevalent due to the oxygen vacancy in anti-site defect structure of the compound) toward its transformation to defect fluorite structure as found in Dy{sub 2}Zr{sub 2}O{sub 7}. A comparison of the changes perceived with PAS as compared to XRD analysis is critically assayed.

Chakraborty, Keka [Applied Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)] [Applied Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Bisoi, Abhijit [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)] [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Ganguly, Bichitra Nandi, E-mail: bichitra.ganguly@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Grover, Vinita; Sayed, Farheen Nasir; Tyagi, A.K. [Applied Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)] [Applied Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2012-11-15T23:59:59.000Z

64

Scanning transmission X-ray microscopy probe for in situ mechanism study of graphene-oxide-based resistive random access memory  

Science Journals Connector (OSTI)

An in situ probe for scanning transmission X-ray microscopy has been developed and applied to the study of the bipolar resistive switching mechanism in an Al/graphene oxide/Al resistive random access memory device.

Nho, H.W.

2013-11-28T23:59:59.000Z

65

Solid electrolyte aided study of the mechanism of CO oxidation on polycrystalline platinum  

SciTech Connect (OSTI)

The mechanism of CO oxidation on polycrystalline Pt at atmospheric pressure has been investigated by combining kinetic and simultaneous potentiometric studies in a gradientless reactor containing one or two polycrystalline Pt films supported on stabilized zirconia. The initial oxidation state of the catalyst was found to have an important effect both on the steady-state behavior and on the waveform of rate and emf oscillations. A simple kinetic model where both oxygen adsorption and surface reaction are rate limiting is found to describe semiquantitatively the steady-state kinetic and potentiometric results both on preoxidized and on prereduced surfaces. The oscillatory behavior of the system was studied in detail by simultaneous mass spectroscopic monitoring of the concentrations of O/sub 2/ and CO/sub 2/. The kinetic and potentiometric results suggest strongly that the oscillations are caused by periodic formation and consumption of surface PtO/sub 2/. The formation of PtO/sub 2/ is verified by a series of surface CO-O/sub 2/ titration experiments. The experiments with two polycrystalline films show that oscillation synchronization occurs via the gas phase as the two films exposed to the same gaseous environment exhibit synchronous oscillations in the surface oxygen activity.

Yentekakis, I.V.; Neophytides, S.; Vayenas, C.G.

1988-05-01T23:59:59.000Z

66

Cost Study for Manufacturing of Solid Oxide Fuel Cell Power Systems  

SciTech Connect (OSTI)

Solid oxide fuel cell (SOFC) power systems can be designed to produce electricity from fossil fuels at extremely high net efficiencies, approaching 70%. However, in order to penetrate commercial markets to an extent that significantly impacts world fuel consumption, their cost will need to be competitive with alternative generating systems, such as gas turbines. This report discusses a cost model developed at PNNL to estimate the manufacturing cost of SOFC power systems sized for ground-based distributed generation. The power system design was developed at PNNL in a study on the feasibility of using SOFC power systems on more electric aircraft to replace the main engine-mounted electrical generators [Whyatt and Chick, 2012]. We chose to study that design because the projected efficiency was high (70%) and the generating capacity was suitable for ground-based distributed generation (270 kW).

Weimar, Mark R.; Chick, Lawrence A.; Gotthold, David W.; Whyatt, Greg A.

2013-09-30T23:59:59.000Z

67

Studies on the chemical synthesis and characterization of lead oxide nanoparticles with different organic capping agents  

SciTech Connect (OSTI)

Lead oxide (PbO) nanoparticles were chemically synthesized using Lead (II) acetate as precursor. The effects of organic capping agents such as Oleic acid, Ethylene Diamine Tetra Acetic acid (EDTA) and Cetryl Tri Methyl Butoxide (CTAB) on the size and morphology of the nanoparticles were studied. Characterization techniques such as X-ray diffraction (XRD), Fourier Transform-Infrared spectroscopy (FT-IR), Photoluminescence (PL) Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscopy (TEM) were used to analyse the prepared nanoparticles for their physical, structural and optical properties. The characterization studies reveal that the synthesized PbO nanoparticles had well defined crystalline structure and sizes in the range of 25 nm to 36 nm for capping agents used and 40 nm for pure PbO nanoparticles.

Arulmozhi, K. T., E-mail: arulsheelphy@gmail.com [Physics Wing (DDE), Annamalai University, Tamil Nadu, India - 608 002 (India); Mythili, N. [Department of Physics, Annamalai University, Tamil Nadu, India - 608 002 (India)] [Department of Physics, Annamalai University, Tamil Nadu, India - 608 002 (India)

2013-12-15T23:59:59.000Z

68

Raman scattering studies of the GaAs native oxide interface  

Science Journals Connector (OSTI)

Oxide filmsgrown by heat treatment on the 100 and 111 faces of GaAs have been studied by Raman backscattering. A spectrum consisting of the bulk LO and TO lines of GaAs and two additional lines labeled R1 and R2 is observed on all samples prepared at temperatures above 435° C. The additional modes are attributed to an interface region of perhaps several hundred angstroms thickness beneath the oxide film. This structure appears to be made unstable by chemical removal of the film. After the film is removed the spectrum is annealed (returns to that of GaAs) in a matter of weeks at room temperature and in about 1 h at 400° C whether the annealing atmosphere is N2 O2 or forming gas. One of the modes R2 appears to scatter as a scalar i.e. a diagonal Raman matrix element. Spectra by the R1 mode on the other hand appear to be largely unpolarized or possibly slightly nondiagonal in character. Some speculations about the possible nature of the interface region are presented.

J. A. Cape; W. E. Tennant; L. G. Hale

1977-01-01T23:59:59.000Z

69

Oxidation of zinc in alkaline solutions studied by electrochemical impedance spectroscopy  

SciTech Connect (OSTI)

Electrochemical dissolution and passivation reactions of zinc have been studied in 1.0 M KOH solutions by electrochemical impedance spectroscopy. Equivalent circuits have been worked out by simulating the impedance data and using the results to model the dissolution and passivation reactions. A Tafel plot constructed from the charge-transfer resistances provides an exchange current of 0.11 A/cm{sup 2} and an {alpha} value of 0.36 for zinc oxidation. The maximum rate of zinc oxidation is observed at about {minus}1.30 V vs. the Hg/HgO reference electrode as judged from the charge-transfer resistance minimum obtained from impedance measurements. A negative polarization resistance with a reverse semicircle on the Nyquist plot illustrates the transition process from an active to passive potential region at {minus}1.10 V. At high anodic over-potentials, the zinc electrode behaved as a semiconductor electrode due to a compact ZnO passive film formed on the electrode surface.

Cai, M.; Park, S.M. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemistry

1996-12-01T23:59:59.000Z

70

An assessment of the validity of cerium oxide as a surrogate for plutonium oxide gallium removal studies  

SciTech Connect (OSTI)

Methods for purifying plutonium metal have long been established. These methods use acid solutions to dissolve and concentrate the metal. However, these methods can produce significant mixed waste, that is, waste containing both radioactive and chemical hazards. The volume of waste produced from the aqueous purification of thousands of weapons would be expensive to treat and dispose. Therefore, a dry method of purification is highly desirable. Recently, a dry gallium removal research program commenced. Based on initial calculations, it appeared that a particular form of gallium (gallium suboxide, Ga{sub 2}O) could be evaporated from plutonium oxide in the presence of a reducing agent, such as small amounts of hydrogen dry gas within an inert environment. Initial tests using ceria-based material (as a surrogate for PuO{sub 2}) showed that thermally-induced gallium removal (TIGR) from small samples (on the order of one gram) was indeed viable. Because of the expense and difficulty of optimizing TIGR from plutonium dioxide, TIGR optimization tests using ceria have continued. This document details the relationship between the ceria surrogate tests and those conducted using plutonia.

Kolman, D.G.; Park, Y.; Stan, M.; Hanrahan, R.J. Jr.; Butt, D.P.

1999-03-01T23:59:59.000Z

71

Spectroscopic Studies of O-Vacancy Defects in Transition Metal Oxides  

SciTech Connect (OSTI)

Dielectrics comprised of nano-crystalline HfO{sub 2} in gate stacks with thin SiO{sub 2}/SiON interfacial transition regions display significant asymmetries with respect to trapping of Si substrate injected holes and electrons. Based on spectroscopic studies, and guided by ab initio theory, electron and hole traps in HfO{sub 2} and other transition metal elemental oxides are assigned to O-atom divacancies clustered at internal grain boundaries of nano-crystalline films. Engineering solutions in which grain boundary defects are suppressed include: (i) ultra-thin, <2 nm, HfO{sub 2} fims, (ii) chemically phase separated high HfO2 content silicate films, and (iii) non-crystalline Zr/Hf Si oxynitride films.

Lucovsky, G.; Luning, J.; Fleming, L.B.; Ulrich, M.D.; Rowe, J.E.; Seo, H.; Lee, S.; Lysaght, P.; Bersuker, G.

2009-06-03T23:59:59.000Z

72

Catalytic partial oxidation of iso-octane over rhodium catalysts: An experimental, modeling, and simulation study  

SciTech Connect (OSTI)

Catalytic partial oxidation of iso-octane over a rhodium/alumina coated honeycomb monolith is experimentally and numerically studied at short-contact times for varying fuel-to-oxygen ratios. A new experimental set-up with well-defined inlet and boundary conditions is presented. The conversion on the catalyst and in the gas-phase is modeled by detailed reaction mechanisms including 857 gas-phase and 17 adsorbed species. Elementary-step based heterogeneous and homogeneous reaction mechanisms are implemented into two-dimensional flow field description of a single monolith channel. Experiment and simulation provide new insights into the complex reaction network leading to varying product distribution as function of fuel-to-oxygen ratio. At fuel rich conditions, the formation of by-products that can serve as coke precursors is observed and interpreted. (author)

Hartmann, M.; Minh, H.D. [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Maier, L. [Institute for Nuclear and Energy Technology, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Deutschmann, O. [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Institute for Nuclear and Energy Technology, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)

2010-09-15T23:59:59.000Z

73

Experimental Study of Electron Transport through Nanometer-Scale Metal-Oxide Junctions  

E-Print Network [OSTI]

-annealing. The resistive bistability effect has been observed for all these materials, with particularly high switching, crested barrier, rapid thermal annealing, endurance, resistive bistability, reproducibility. #12;v List properties of Nb/Al/Nb junctions fabricated using thermal oxidation or rf-plasma oxidation at various

74

Ab initio atomistic thermodynamics study of the early stages of Cu(100) oxidation  

E-Print Network [OSTI]

­3 catalytic conversion of nitrogen oxides,4 water-gas shift,5,6 and preventing CO poisoning in fuel cells.7 the nucleation limit of Cu2O, they are likely to exist due to kinetic hindrance. 1 #12;I. INTRODUCTION Oxidation

McGaughey, Alan

75

Interaction of copper oxides with reaction medium in heterogeneous catalytic oxidation of carbon monoxide by molecular oxygen. IV. IR spectroscopic study of carbon monoxide interaction with copper oxide surface  

SciTech Connect (OSTI)

An IR spectroscopic study has been made of the interaction of CO with CuO prepared in different ways, and the interaction of O/sub 2/ with carbon monoxide preadsorbed on CuO. A number of Cu/sup +/CO surface complexes have been detected (2114-2148 cm/sup -1/) with a heat of adsorption about 79.5-180 kJ/mole. From an analysis of the nature of these complexes, we have evaluated the processes taking place on the CuO surface when it interacts with CO and have compared the properties of massive CuO with those of CuO on oxide supports. The data are interpreted on the assumption that extended defects - dislocations - exist and play an important role, determining to a considerable degree the properties of the massive CuO in the reaction of CO oxidation.

Lokhov, Y.A.; Popovskii, V.V.; Sadykov, V.A.; Tikhov, S.F.

1985-08-01T23:59:59.000Z

76

Experimental studies and thermodynamic modelling of volatilities of uranium, plutonium, and americium from their oxides and from their oxides interacted with ash  

SciTech Connect (OSTI)

The purpose of this study is to identify the types and amounts of volatile gaseous species of U, Pu, and Am that are produced in the combustion chamber offgases of mixed waste oxidation processors. Primary emphasis is on the Rocky Flats Plant Fluidized Bed Incinerator. Transpiration experiments have been carried out on U{sub 3}O{sub 8}(s), U{sub 3}O{sub 8} interacted with various ash materials, PuO{sub 2}(s), PuO{sub 2} interacted with ash materials, and a 3%PuO{sub 2}/0.06%AmO{sub 2}/ash material, all in the presence of steam and oxygen, and at temperatures in the vicinity of 1,300 K. UO{sub 3}(g) and UO{sub 2}(OH){sub 2}(g) have been identified as the uranium volatile species and thermodynamic data established for them. Pu and Am are found to have very low volatilities, and carryover of Pu and Am as fine dust particulates is found to dominate over vapor transport. The authors are able to set upper limits on Pu and Am volatilities. Very little lowering of U volatility is found for U{sub 3}O{sub 8} interacted with typical ashes. However, ashes high in Na{sub 2}O (6.4 wt %) or in CaO (25 wt %) showed about an order of magnitude reduction in U volatility. Thermodynamic modeling studies were carried out that show that for aluminosilicate ash materials, it is the presence of group I and group II oxides that reduces the activity of the actinide oxides. K{sub 2}O is the most effective followed by Na{sub 2}O and CaO for common ash constituents. A more major effect in actinide activity lowering could be achieved by adding excess group I or group II oxides to exceed their interaction with the ash and lead to direct formation of alkali or alkaline earth uranates, plutonates, and americates.

Krikorian, O.H.; Ebbinghaus, B.B.; Adamson, M.G.; Fontes, A.S. Jr.; Fleming, D.L.

1993-09-15T23:59:59.000Z

77

HRTEM Study of Oxide Nanoparticles in K3-ODS Ferritic Steel Developed for Radiation Tolerance  

SciTech Connect (OSTI)

Crystal and interfacial structures of oxide nanoparticles and radiation damage in 16Cr-4.5Al-0.3Ti-2W-0.37 Y{sub 2}O{sub 3} ODS ferritic steel have been examined using high-resolution transmission electron microscopy (HRTEM) techniques. Oxide nanoparticles with a complex-oxide core and an amorphous shell were frequently observed. The crystal structure of complex-oxide core is identified to be mainly monoclinic Y{sub 4}Al{sub 2}O{sub 9} (YAM) oxide compound. Orientation relationships between the oxide and the matrix are found to be dependent on the particle size. Large particles (> 20 nm) tend to be incoherent and have a spherical shape, whereas small particles (< 10 nm) tend to be coherent or semi-coherent and have a faceted interface. The observations of partially amorphous nanoparticles and multiple crystalline domains formed within a nanoparticle lead us to propose a three-stage mechanism to rationalize the formation of oxide nanoparticles containing core/shell structures in as-fabricated ODS steels. Effects of nanoparticle size and density on cavity formation induced by (Fe{sup 8+} + He{sup +}) dual-beam irradiation are briefly addressed.

Hsiung, L; Fluss, M; Tumey, S; Kuntz, J; El-Dasher, B; Wall, M; Choi, W; Kimura, A; Willaime, F; Serruys, Y

2009-11-02T23:59:59.000Z

78

3-Hydroxylysine, a Potential Marker for Studying Radical-Induced Protein Oxidation  

Science Journals Connector (OSTI)

5-Hydroxylysines are natural products formed by lysyl oxidase and are therefore not good markers of radical-mediated oxidation. ... Free radicals are known to be generated either by normal metabolic processes during electron transport chains and redox reactions of enzymes or as a result of exposure to exogenous factors such as UV light, radiation, and various chemicals. ... As 5OHLys is a naturally occuring amino acid (present in collagen as a result of lysine oxidation by the enzyme lysyl oxidase) and 4OHLys is not fully recovered after protein hydrolysis treatment, these species are probably not useful markers for protein oxidation. ...

Bénédicte Morin; William A. Bubb; Michael J. Davies; Roger T. Dean; Shanlin Fu

1998-10-03T23:59:59.000Z

79

A rapid compression machine study of the oxidation of propane in the negative temperature coefficient regime  

SciTech Connect (OSTI)

The oxidation of propane has been studied in the temperature range 680-970 K at compressed gas pressures of 21, 27, and 37 atm and at varying equivalence ratios of 0.5, 1.0, and 2.0. These data are consistent with other experiments presented in the literature for alkane fuels in that, when ignition delay times are plotted as a function of temperature, a characteristic negative coefficient behavior is observed. In addition, these data were simulated using a detailed chemical kinetic model. It was found that qualitatively the model correctly simulated the effect of change in equivalence ratio and pressure, predicting that fuel-rich, high-pressure mixtures ignite fastest, while fuel-lean, low-pressure mixtures ignite slowest. Moreover, reactivity as a function of temperature is well captured, with the model predicting negative temperature coefficient behavior similar to the experiments. Quantitatively the model is faster than experiment for all mixtures at the lowest temperatures (650-750 K) and is also faster than experiment throughout the entire temperature range for fuel-lean mixtures. (author)

Gallagher, S.M.; Curran, H.J.; Metcalfe, W.K.; Healy, D.; Simmie, J.M. [Combustion Chemistry Centre, National University of Ireland, Galway (Ireland); Bourque, G. [Rolls-Royce Canada, Montreal (Canada)

2008-04-15T23:59:59.000Z

80

STUDY MAGNETIC EXCITATIONS IN DOPED TRANSITION METAL OXIDES USING INELASTIC NEUTRON SCATTERING  

SciTech Connect (OSTI)

Understanding the interplay between magnetism and superconductivity continues to be a “hot” topic in modern condensed matter physics. The discovery of high-temperature superconductivity in iron-based materials in 2008 provided an unique opportunity to compare and contrast these materials with traditional high-Tc copper oxide superconductors. Neutron scattering plays an important role in determining the dynamical spin properties in these materials. This proposal is a continuation of previous DOE supported proposal. This report summarizes the final progress we have made over from May 2005 till Aug. 2013. Overall, we continue to carry out extensive neutron scattering experiments on Fe-based materials, focusing on understanding their magnetic properties. In addition, we have established a materials laboratory at UT that has allowed us to grow these superconductors. Because neutron scattering typically demands a large amount of samples, by growing these materials in our own laboratory, we can now pursuit neutron scattering experiments over the entire electronic phase diagram, focusing on regions of interests. The material synthesis laboratory at UT was established entirely with the support of DOE funding. This not only allowed us to carry out neutron scattering experiments, but also permit us to provide samples to other US/International collaborators for studying these materials.

Dai, Pengcheng

2014-02-18T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Direct Non-oxidative Methane Conversion by Non-thermal Plasma: Experimental Study  

Science Journals Connector (OSTI)

The direct non-oxidative conversion of methane to higher hydrocarbons in non-thermal plasma, namely dielectric barrier discharge and corona discharge, has been investigated experimentally at atmospheric pressure....

Yun Yang

2003-06-01T23:59:59.000Z

82

Direct Non-oxidative Methane Conversion by Non-thermal Plasma: Modeling Study  

Science Journals Connector (OSTI)

The direct non-oxidative conversion of methane to higher hydrocarbons ... dielectric barrier discharges has been investigated theoretically at atmospheric pressure. Preliminary modeling of the results is...2...hy...

Yun Yang

2003-06-01T23:59:59.000Z

83

Laboratory flammability studies of mixtures of hydrogen, nitrous oxide, and air  

SciTech Connect (OSTI)

At the request of the Department of Energy and the Westinghouse Hanford Company, the Bureau of Mines has investigated the flammability of mixtures of hydrogen, nitrous oxide, and air. This work is relevant to the possible hazards of flammable gas generation from nuclear waste tanks at Hanford, WA. The tests were performed in a 120-L spherical chamber under both quiescent and turbulent conditions using both electric spark and pyrotechnic ignition sources. The data reported here for binary mixtures of hydrogen in air generally confirm the data of previous investigators, but they are more comprehensive than those reported previously. The results clarify to a greater extent the complications associated with buoyancy, turbulence, and selective diffusion. The data reported here for ternary mixtures of hydrogen and nitrous oxide in air indicate that small additions of nitrous oxide (relative to the amount of air) have little effect, but that higher concentrations of nitrous oxide (relative to air) significantly increase the explosion hazard.

Cashdollar, K L; Hertzberg, M; Zlochower, I A; Lucci, C E; Green, G M; Thomas, R A [Bureau of Mines, Pittsburgh, PA (United States). Pittsburgh Research Center

1992-06-26T23:59:59.000Z

84

Mechanistic, sensitivity, and uncertainty studies of the atmospheric oxidation of dimethylsulfide  

E-Print Network [OSTI]

The global-scale emissions and reactivity of dimethylsulfide (CH3SCH3, DMS) make it an integral component in the atmospheric sulfur cycle. DMS is rapidly oxidized in the atmosphere by a complex gas-phase mechanism involving ...

Lucas, Donald David, 1969-

2003-01-01T23:59:59.000Z

85

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass  

E-Print Network [OSTI]

biomass combustion and gasification Milena Nowakowska, Olivier Herbinet, Anthony Dufour, Pierre. Methoxyphenols are one of the main precursors of PAH and soot in biomass combustion and gasification. Keywords: Anisole; Pyrolysis; Oxidation; Tars; Biomass; Kinetic modeling Corresponding author

Paris-Sud XI, Université de

86

Fundamental studies of heterostructured oxide thin film electrocatalysts for oxygen reduction at high temperatures  

E-Print Network [OSTI]

Searching for active and cost-effective catalysts for oxygen electrocatalysis is essential for the development of efficient clean electrochemical energy technologies. Perovskite oxides are active for surface oxygen exchange ...

Crumlin, Ethan J

2012-01-01T23:59:59.000Z

87

Experimental Studies of Hydroxyl Radical Initiated Tropospheric Oxidation of Unsaturated Hydrocarbons  

E-Print Network [OSTI]

radical, followed by chain propagating radical reactions. Their oxidation is the major source for ground level ozone formation in both rural and urban area and understanding their chemistry is essential for regional air quality modeling. Until recently...

Ghosh, Buddhadeb

2011-10-21T23:59:59.000Z

88

Development of Analytical Methods Coupled to Microdialysis Sampling for Studying Biomarkers of Oxidative Stress  

E-Print Network [OSTI]

generation would increase in biological systems due to induced oxidative stress. In one investigation, a capillary electrophoresis (CE) method with ultra-violet (UV) detection was developed employing pH-mediated stacking, an on-column preconcentration...

Hoque, Md Ehsanul

2007-12-18T23:59:59.000Z

89

Physical characterization of magmatic liquids. [Ultrasonic and Brillouin Scattering Studies of Natural and Synthetic Silicates and Oxides  

SciTech Connect (OSTI)

This report describes a research project that was conducted from August 15, 1985 to February 28, 1992. The project was based on the ultrasonic studies of natural and synthetic silicate melts, and the study of Brillouin scattering of synthetic silicates and oxides. Measurements of the compressional wave velocity and attenuation can be established using the ultrasonic methods. Temperature dependences of silicates can be established by the Brillouin scattering. (MB)

Manghnani, M.H.

1992-06-05T23:59:59.000Z

90

Extremality of translation-invariant phases for a finite-state SOS-model on the binary tree  

E-Print Network [OSTI]

We consider the SOS (solid-on-solid) model, with spin values $0,1,2$, on the Cayley tree of order two (binary tree). We treat both ferromagnetic and antiferromagnetic coupling, with interactions which are proportional to the absolute value of the spin differences. We present a classification of all translation-invariant phases (splitting Gibbs measures) of the model: We show uniqueness in the case of antiferromagnetic interactions, and existence of up to seven phases in the case of ferromagnetic interactions, where the number of phases depends on the interaction strength. Next we investigate whether these states are extremal or non-extremal in the set of all Gibbs measures, when the coupling strength is varied, whenever they exist. We show that two states are always extremal, two states are always non-extremal, while three of the seven states make transitions between extremality and non-extremality. We provide explicit bounds on those transition values, making use of algebraic properties of the models, and an adaptation of the method of Martinelli, Sinclair, Weitz.

C. Kuelske; U. A. Rozikov

2014-11-21T23:59:59.000Z

91

Aromatic hydroxylation. 8. A radiation chemical study of the oxidation of hydroxycyclohexadienyl radicals  

SciTech Connect (OSTI)

Substituted hydroxycyclohexadienyl radicals have been generated by pulse radiolysis of N/sub 2/O-saturated aqueous solutions of monosubstituted benzene derivatives. Their rates of disproportionation/dimerization and of oxidation by Fe(CN)/sub 6//sup 3 -/ and by IrCl/sub 6//sup 2 -/ have been measured by optical and conductimetric methods. For the fluoro- and chlorohydroxycyclohexadienyl radicals disproportionation is shown to involve hydrogen atom abstraction rather than electron transfer. However, the Fe(CN)/sub 6//sup 3 -/ oxidation of the substituted hydroxycyclohexadienyl radicals occurs by a rate-determining electron transfer followed by a fast proton loss rather than by hydrogen atom abstraction or synchronous removal of an electron and a proton. A plot of the log of the rate constants for oxidation against Hammett sigma/sup +/ constants gives a good linear relationship with a rho value of -3.0 +/- 0.1. With the more powerful oxidant IrCl/sub 6//sup -/, the electron-transfer oxidation of all but the least reactive hydroxycyclohexadienyl radicals is diffusion controlled.

Buxton, G.V.; Langan, J.R.; Smith, J.R.L.

1986-11-06T23:59:59.000Z

92

Oxidation of ligand-protected aluminum clusters: An ab initio molecular dynamics study  

SciTech Connect (OSTI)

We report Car-Parrinello molecular dynamics simulations of the oxidation of ligand-protected aluminum clusters that form a prototypical cluster-assembled material. These clusters contain a small aluminum core surrounded by a monolayer of organic ligand. The aromatic cyclopentadienyl ligands form a strong bond with surface Al atoms, giving rise to an organometallic cluster that crystallizes into a low-symmetry solid and is briefly stable in air before oxidizing. Our calculations of isolated aluminum/cyclopentadienyl clusters reacting with oxygen show minimal reaction between the ligand and O{sub 2} molecules at simulation temperatures of 500 and 1000 K. In all cases, the reaction pathway involves O{sub 2} diffusing through the ligand barrier, splitting into atomic oxygen upon contact with the aluminum, and forming an oxide cluster with aluminum/ligand bonds still largely intact. Loss of individual aluminum-ligand units, as expected from unimolecular decomposition calculations, is not observed except following significant oxidation. These calculations highlight the role of the ligand in providing a steric barrier against oxidizers and in maintaining the large aluminum surface area of the solid-state cluster material.

Alnemrat, Sufian; Hooper, Joseph P., E-mail: jphooper@nps.edu [Department of Physics, Naval Postgraduate School, Monterey, California 93943 (United States)

2014-03-14T23:59:59.000Z

93

Catalytic oxidation of carbon monoxide over Ir/SiO/sub 2/. An in situ infrared and kinetic study  

SciTech Connect (OSTI)

The oxidation of CO on a highly dispersed Ir/SiO/sub 2/ catalyst has been studied both in a Pyrex microreactor and by using an in situ infrared cell-reactor. Multiple steady states obtained under conditions of increasing and decreasing CO partial pressure were observed to lead to reaction rate hysteresis. The area under the hysteresis loop is strongly dependent on reaction temperature. This is explained by invoking competitive adsorption between CO and O/sub 2/ as a function of temperature. Self-sustained oscillations were obtained when certain conditions of partial pressure and temperature were met. Quantitative estimates of fluctuations in surface coverage and temperature during these oscillations were 10% and 3K, respectively. CO islands of reactivity were not observed under the conditions of this study. The presence of higher oxidation states of IR could not be unequivocally determined by using infrared spectroscopy. 29 references, 8 figures, 2 tables.

Saymeh, R.A.; Gonzalez, R.D.

1986-02-13T23:59:59.000Z

94

Acid strength of silica-supported oxide catalysts studied by microcalorimetric measurements of pyridine adsorption  

SciTech Connect (OSTI)

Microcalorimetric measurements of the differential heat of pyridine adsorption were used to probe the distribution of acid strength on a series of silica-supported oxide catalysts. Depositing oxides of the following cations onto silica increased the acid strength of the catalyst: Ga{sup 3{plus}}, Zn{sup 2{plus}}, Al{sup 3{plus}}, Fe{sup 3{plus}}, Fe{sup 2{plus}}, Mg{sup 2{plus}}, and Sc{sup 3{plus}}. The acid strength distribution curves for the supported oxide samples showed either two or three regions of constant heat of adsorption while silica had an energetically homogeneous surface. The Ga, Al, and Sc samples were found to have both Bronsted and Lewis acidity while the remaining samples showed only Lewis acidity. Incremental adsorption of pyridine indicated that the initial region of highest heat corresponds to strong Lewis acidity while intermediate heats seemed to be due to weaker Lewis acid sites or a combination of Lewis and Bronsted acid sites. The final region of lowest heat was due to H-bonded pyridine on silica. Estimates of the entropies of adsorption were determined, providing information about the mobility of the adsorbed pyridine molecules. The initial differential heat of adsorption increases proportionally to the Sanderson electronegativity of the added oxide.

Cardona-Martinez, N.; Dumesic, J.A. (Univ. of Wisconsin, Madison (USA))

1991-02-01T23:59:59.000Z

95

Nickel oxide reduction studied by environmental TEM and in situ XRD Q. Jeangros1  

E-Print Network [OSTI]

cell (SOFC) technology, as it determines the structure of the electronic conductor on the anode side reduction and subsequent Ni behaviour under H2 is of practical importance in the field of solid oxide fuel the Scherrer formula) and H2/H2O mass spectrometer signals are monitored. The recorded images and diffraction

Dunin-Borkowski, Rafal E.

96

Reactions of Polycarbonate with Cyclohexene Oxide and Phosphites: A Density Functional Study  

E-Print Network [OSTI]

bisphenol A polycarbonate (BPA-PC). We describe density functional (DF) calculations of the reactions of cyclohexene oxide (CHO, cyclohexane epoxide) and phosphites with chain segments of BPA- PC, with the aim to organic molecules and polymers, focusing on bisphenol A polycarbonate (BPA-PC). BPA-PC is an important

97

A study of degradation of indium tin oxide thin films on glass for display applications  

Science Journals Connector (OSTI)

Indium tin oxide (ITO) has been widely used in liquid crystal displays (LCD). Contamination and moisture have proved to have the adverse effect of causing ITO corrosion/degradation. The purpose of this paper is to determine if scratching the surface ... Keywords: Accelerated degradation test, ITO corrosion, ITO degradation, Scratching

W. S. Leung; Y. C. Chan; S. M. Lui

2013-01-01T23:59:59.000Z

98

Experimental study of the oxidation of methyl oleate in a jet-stirred , Mohammed Hichem Hakkaa  

E-Print Network [OSTI]

.1016/j.combustflame.2009.12.008 #12;1. Introduction The interest in the oxidation of biodiesel fuels is increasing because of their use along with conventional diesel fuels in internal combustion engines [1], [2], [3] and [4]. Biodiesel fuels are alternative renewable fuels which are obtained from vegetable oils

Paris-Sud XI, Université de

99

Modeling study of the lowtemperature oxidation of large methyl esters from C11 to C19  

E-Print Network [OSTI]

in biodiesel fuels has been investigated. Models have been developed for these species and then detailed; Biodiesel fuels; Modeling; Oxidation * Corresponding author: Olivier Herbinet Laboratory of Reaction the differences with the combustion of alkanes induced by the ester function. While biodiesel fuels deriving from

Boyer, Edmond

100

Study of Interfacial Interactions Using Thing Film Surface Modification: Radiation and Oxidation Effects in Materials  

SciTech Connect (OSTI)

Interfaces play a key role in dictating the long-term stability of materials under the influence of radiation and high temperatures. For example, grain boundaries affect corrosion by way of providing kinetically favorable paths for elemental diffusion, but they can also act as sinks for defects and helium generated during irradiation. Likewise, the retention of high-temperature strength in nanostructured, oxide-dispersion strengthened steels depends strongly on the stoichiometric and physical stability of the (Y, Ti)-oxide particles/matrix interface under radiation and high temperatures. An understanding of these interfacial effects at a fundamental level is important for the development of materials for extreme environments of nuclear reactors. The goal of this project is to develop an understanding stability of interfaces by depositing thin films of materials on substrates followed by ion irradiation of the film-substrate system at elevated temperatures followed by post-irradiation oxidation treatments. Specifically, the research will be performed by depositing thin films of yttrium and titanium (~500 nm) on Fe-12%Cr binary alloy substrate. Y and Ti have been selected as thin-film materials because they form highly stable protective oxides layers. The Fe-12%Cr binary alloy has been selected because it is representative of ferritic steels that are widely used in nuclear systems. The absence of other alloying elements in this binary alloy would allow for a clearer examination of structures and compositions that evolve during high-temperature irradiations and oxidation treatments. The research is divided into four specific tasks: (1) sputter deposition of 500 nm thick films of Y and Ti on Fe-12%Cr alloy substrates, (2) ion irradiation of the film-substrate system with 2MeV protons to a dose of 2 dpa at temperatures of 300°C, 500°C, and 700°C, (3) oxidation of as-deposited and ion-irradiated samples in a controlled oxygen environment at 500°C and 700°C, (4) multi-scale computational modeling involving first- principle molecular dynamics (FPMD) and coarse-grained dissipative particle dynamics (DPD) approaches to develop theories underlying the evolution and stability of structures and phases. Samples from Tasks 1 to 3 (above) will be rigorously characterized and analyzed using scanning electron microscopy, Auger electron microscopy, x-ray diffraction, Rutherford back scatter spectroscopy, and transmission electron microscopy. Expected outcomes of the experimental work include a quantitative understanding film-substrate interface mixing, evolution of defects and other phases at the interface, interaction of interfaces with defects, and the ability of the Y and Ti films to mitigate irradiation-assisted oxidation. The aforementioned experimental work will be closely coupled with multi-scale molecular dynamics (MD) modeling to understand the reactions at the surface, the transport of oxidant through the thin film, and the stabilities of the deposited thin films under radiation and oxidation. Simulations of materials property changes under conditions of radiation and oxidation require multiple size domains and a different simulation scheme for each of these domains. This will be achieved by coupling the FPMD and coarse-grained kinetic Monte Carlo (KMC). This will enable the comparison of the results of each simulation approach with the experimental results.

Sridharan, Kumar; Zhang, Jinsuo

2014-01-09T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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to obtain the most current and comprehensive results.


101

Electron Microscopy Study of Novel Ru Doped La0.8Sr0.2CrO3 as Anode Materials for Solid Oxide Fuel Cells (SOFCs)  

E-Print Network [OSTI]

Electron Microscopy Study of Novel Ru Doped La0.8Sr0.2CrO3 as Anode Materials for Solid Oxide Fuel of Materials Science and Engineering, Northwestern University, 2220 Campus Dr. Evanston, IL 60208 Solid Oxide Fuel Cells (SOFCs) have been the center of research activities with the goal of improving energy

Marks, Laurence D.

102

Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption Fine Structure (XAFS) Study  

E-Print Network [OSTI]

Effect of Residence Time on Ni-Sorption Mechanisms on Clay and Oxide Minerals: An X-ray Absorption Fine Structure (XAFS) Study A. M. Scheidegger and G. M. Lamble Metal sorption on clay and oxide in reaction rate has been attributed to metal sorption onto sites of lower reactivity, diffusion

Sparks, Donald L.

103

Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz, Sorina Udroiu, Jean-Paul Viricelle, Christophe Pijolat, Michle Pijolat  

E-Print Network [OSTI]

Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz Single chamber solid oxide fuel cells (SCFC) are an alternative concept to traditional SOFC-gas-shift equilibrium. Introduction Fifteen years ago, Hibino (1) has shown the feasibility of a fuel cell consisting

Boyer, Edmond

104

First Principles Study of Photo-oxidation Degradation Mechanisms in P3HT for Organic Solar Cells  

E-Print Network [OSTI]

We present a theoretical study of degradation mechanisms for photoinduced oxidation in organic polymers in the condensed phase, using poly(3-hexylthiophene)(P3HT) as an example. Applying density functional theory with a hybrid density functional and periodic boundary conditions that account for steric effects and permit the modeling of interchain chemical reactions, we investigate reaction pathways that may lead to the oxidation of thiophene backbone as a critical step toward disrupting the polymer conjugation. We calculate energy barriers for reactions of the P3HT backbone with oxidizing agents including hydroxyl radical (OH$\\cdot$), hydroperoxide (ROOH), and peroxyl radical (ROO$\\cdot$), following a UV-driven radical reaction starting at the $\\alpha$-carbon of the alkyl side chain as suggested by infrared (IR) and X-ray photoemission (XPS) spectrosocopy studies. The results strongly suggest that an attack of OH$\\cdot$ on sulfur in P3HT is unlikely to be thermodynamically favored. On the other hand, an attack of a peroxyl radical on the side chain on the P3HT backbone may provide low barrier reaction pathways to photodegradation of P3HT and other polymers with side chains. The condensed phase setting is found to qualitatively affect predictions of degradation processes.

Na Sai; Kevin Leung; Judit Zádor; Graeme Henkelman

2014-03-19T23:59:59.000Z

105

Pyroprocessing of oxidized sodium-bonded fast reactor fuel - An experimental study of treatment options for degraded EBR-II fuel  

SciTech Connect (OSTI)

An experimental study was conducted to assess pyrochemical treatment options for degraded EBR-II fuel. As oxidized material, the degraded fuel would need to be converted back to metal to enable electrorefining within an existing electro-metallurgical treatment process. A lithium-based electrolytic reduction process was studied to assess the efficacy of converting oxide materials to metal with a particular focus on the impact of zirconium oxide and sodium oxide on this process. Bench-scale electrolytic reduction experiments were performed in LiCl-Li{sub 2}O at 650 C. degrees with combinations of manganese oxide (used as a surrogate for uranium oxide), zirconium oxide, and sodium oxide. In the absence of zirconium or sodium oxide, the electrolytic reduction of MnO showed nearly complete conversion to metal. The electrolytic reduction of a blend of MnO-ZrO{sub 2} in LiCl - 1 wt% Li{sub 2}O showed substantial reduction of manganese, but only 8.5% of the zirconium was found in the metal phase. The electrolytic reduction of the same blend of MnO-ZrO{sub 2} in LiCl - 1 wt% Li{sub 2}O - 6.2 wt% Na{sub 2}O showed substantial reduction of manganese, but zirconium reduction was even less at 2.4%. This study concluded that ZrO{sub 2} cannot be substantially reduced to metal in an electrolytic reduction system with LiCl - 1 wt% Li{sub 2}O at 650 C. degrees due to the perceived preferential formation of lithium zirconate. This study also identified a possible interference that sodium oxide may have on the same system by introducing a parasitic and cyclic reaction of dissolved sodium metal between oxidation at the anode and reduction at the cathode. When applied to oxidized sodium-bonded EBR-II fuel (e.g., U-10Zr), the prescribed electrolytic reduction system would not be expected to substantially reduce zirconium oxide, and the accumulation of sodium in the electrolyte could interfere with the reduction of uranium oxide, or at least render it less efficient.

Hermann, S.D.; Gese, N.J. [Separations Department, Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States); Wurth, L.A. [Zinc Air Inc., 5314-A US Hwy 2 West, Columbia Falls, MT 59912 (United States)

2013-07-01T23:59:59.000Z

106

Xanes Study of Hydrothermal Mo-V-Based Mixed Oxide M1-Phase Catalysts for the (Amm)oxidation of propane  

SciTech Connect (OSTI)

The hydrothermal Mo-V-based mixed oxide catalysts possessing the M1-phase structure were investigated by XANES and in situ X-ray diffraction under ambient and dynamic redox conditions in the presence of O{sub 2} and H{sub 2} at 693 K. Under ambient conditions, XANES, with the use of model compounds, suggested oxidation states of Nb, Te, Mo, and V close to 5+, 4+, 6+, and 4+, respectively, in the bulk M1 phase. The oxidation state changes of Nb, Te, and Mo were not detected under the dynamic redox conditions employed, while the pre-edge peak of vanadium in the M1 phase exhibited small, reproducible shifts, suggesting that VO{sub x} is the active catalytic species in the bulk M1-phase catalysts for selective (amm)oxidation of propane.

Shiju, N.R. [University of Cincinnati; Rondinone, Adam Justin [ORNL; Overbury, Steven {Steve} H [ORNL; Mullins, David R [ORNL; Schwartz, Viviane [ORNL; Guliants, Vadim V. [University of Cincinnati

2008-01-01T23:59:59.000Z

107

XANES Study of Hydrothermal Mo-V-Based Mixed Oxide M1-Phase Catalysts for the (Amm)oxidation of Propane  

SciTech Connect (OSTI)

The hydrothermal Mo-V-based mixed oxide catalysts possessing the M1-phase structure were investigated by XANES and in situ X-ray diffraction under ambient and dynamic redox conditions in the presence of O{sub 2} and H{sub 2} at 693 K. Under ambient conditions, XANES, with the use of model compounds, suggested oxidation states of Nb, Te, Mo, and V close to 5+, 4+, 6+, and 4+, respectively, in the bulk M1 phase. The oxidation state changes of Nb, Te, and Mo were not detected under the dynamic redox conditions employed, while the pre-edge peak of vanadium in the M1 phase exhibited small, reproducible shifts, suggesting that VO{sub x} is the active catalytic species in the bulk M1-phase catalysts for selective (amm)oxidation of propane.

Shuju, N.; Rondinone, A; Mullins, D; Schwartz, V; Overbury, S; Gulaints, V

2008-01-01T23:59:59.000Z

108

Xanes Study of Hydrothermal Mo-V-Based Mixed Oxide M1-Phase Catalysts for the (Amm)oxidation of Propane  

SciTech Connect (OSTI)

The hydrothermal Mo-V-based mixed oxide catalysts possessing the M1-phase structure were investigated by XANES and in situ X-ray diffraction under ambient and dynamic redox conditions in the presence of O{sub 2} and H{sub 2} at 693 K. Under ambient conditions, XANES, with the use of model compounds, suggested oxidation states of Nb, Te, Mo, and V close to 5+, 4+, 6+, and 4+, respectively, in the bulk M1 phase. The oxidation state changes of Nb, Te, and Mo were not detected under the dynamic redox conditions employed, while the pre-edge peak of vanadium in the M1 phase exhibited small, reproducible shifts, suggesting that VO{sub x} is the active catalytic species in the bulk M1-phase catalysts for selective (amm)oxidation of propane.

Mullins, David R [ORNL; Overbury, Steven {Steve} H [ORNL; Rondinone, Adam Justin [ORNL; Schwartz, Viviane [ORNL; Guliants, Vadim [ORNL; Shiju, N.R. [University of Cincinnati

2008-01-01T23:59:59.000Z

109

SISGR-Fundamental Experimental and Theoretical Studies on a Novel Family of Oxide Catalyst Supports for Water Electrolysis  

SciTech Connect (OSTI)

Identification and development of non-noble metal based electro-catalysts or electro-catalysts with significant reduction of expensive noble metal contents (E.g. IrO2, Pt) with comparable electrochemical performance as the standard noble metal/metal oxide for proton exchange membrane (PEM) based water electrolysis would constitute a major breakthrough in the generation of hydrogen by water electrolysis. Accomplishing such a system would not only result reduction of the overall capital costs of PEM based water electrolyzers, but also help attain the targeted hydrogen production cost [< $ 3.0 / gallon gasoline equivalent (gge)] comparable to conventional liquid fuels. In line with these goals, it was demonstrated that fluorine doped IrO2 thin films and nanostructured high surface area powders display remarkably higher electrochemical activity, and comparable durability as pure IrO2 electro-catalyst for the oxygen evolution reaction (OER) in PEM based water electrolysis. Furthermore, corrosion resistant SnO2 and NbO2 support has been doped with F and coupled with IrO2 or RuO2 for use as an OER electro-catalyst. A solid solution of SnO2:F or NbO2:F with only 20 - 30 mol.% IrO2 or RuO2 yielding a rutile structure in the form of thin films and bulk nanoparticles displays similar electrochemical activity and stability as pure IrO2/RuO2. This would lead to more than 70 mol.% reduction in the noble metal oxide content. Novel nanostructured ternary (Ir,Sn,Nb)O2 thin films of different compositions FUNDAMENTAL STUDY OF NANOSTRUCTURED ELECTRO-CATALYSTS WITH REDUCED NOBLE METAL CONTENT FOR PEM BASED WATER ELECTROLYSIS 4 have also been studied. It has been shown that (Ir0.40Sn0.30Nb0.30)O2 shows similar electrochemical activity and enhanced chemical robustness as compared to pure IrO2. F doping of the ternary (Ir,Sn,Nb)O2 catalyst helps in further decreasing the noble metal oxide content of the catalyst. As a result, these reduced noble metal oxide catalyst systems would potentially be preferred as OER electro-catalysts for PEM electrolysis. The excellent performance of the catalysts coupled with its robustness would make them great candidates for contributing to significant reduction in the overall capital costs of PEM based water electrolyzers. This s.thesis provides a detailed fundamental study of the synthesis, materials, characterization, theoretical studies and detailed electrochemical response and potential mechanisms of these novel electro-catalysts for OER processes.

Kumta, Prashant [University of Pittsburgh

2014-10-03T23:59:59.000Z

110

Colloidally Synthesized Monodisperse Rh Nanoparticles Supported on SBA-15 for Size- and Pretreatment-Dependent Studies of CO Oxidation  

SciTech Connect (OSTI)

A particle size dependence for CO oxidation over rhodium nanoparticles of 1.9-11.3 nm has been investigated and determined to be modified by the existence of the capping agent poly(vinylpyrrolidone) (PVP). The particles were prepared using a polyol reduction procedure with PVP as the capping agent. The Rh nanoparticles were subsequently supported on SBA-15 during hydrothermal synthesis to produce Rh/SBA-15 supported catalysts for size-dependent catalytic studies. CO oxidation by O{sub 2} at 40 Torr CO and 100 Torr O{sub 2} was investigated over two series of Rh/SBA-15 catalysts: as-synthesized Rh/SBA-15 covering the full range of Rh sizes and the same set of catalysts after high temperature calcination and reduction. The turnover frequency at 443 K increases from 0.4 to 1.7 s{sup -1} as the particle size decreases from 11.3 to 1.9 nm for the as-synthesized catalysts. After calcination and reduction, the turnover frequency is between 0.1 and 0.4 s{sup -1} with no particle size dependence. The apparent activation energy for all catalysts is {approx}30 kcal mol{sup -1} and is independent of particle size and thermal treatment. Infrared spectroscopy of CO on the Rh nanoparticles indicates that the heat treatments used influence the mode of CO adsorption. As a result, the particle size dependence for CO oxidation is altered after calcination and reduction of the catalysts. CO adsorbs at two distinct bridge sites on as-synthesized Rh/SBA-15, attributable to metallic Rh(0) and oxidized Rh(I) bridge sites. After calcination and reduction, however, CO adsorbs only at Rh(0) atop sites. The change in adsorption geometry and oxidation activity may be attributable to the interaction between PVP and the Rh surface. This capping agent affect may open new possibilities for the tailoring of metal catalysts using solution nanoparticle synthesis methods.

Grass, Michael E.; Joo, Sang Hoon; Somorjai, Gabor A.

2009-02-12T23:59:59.000Z

111

Oxidation of propylene over copper oxide catalysts  

E-Print Network [OSTI]

to the study of propylene oxidation. Dunlop (17) reported that small quantities of iron compounds substantially enhanced the catalytic activity of chromia-alumina catalysts with respect to propylene oxidation, Woodharn (72) has suggested that under... between 360 C and 430oC the rate of propane oxidation decreases as the teznperature is increased, and the rate of conversion to olefins, especially propylene, becomes progressively greater. Above 430 C the proportion of propane converted to ethylene in...

Billingsley, David Stuart

2012-06-07T23:59:59.000Z

112

A Quantitative study of polymeric dispersant adsorption onto oxide-coated titania pigments  

Science Journals Connector (OSTI)

Polyacrylic acid salts and similar copolymers are used extensively in the coatings industry to disperse oxide-coated titania pigments. The effect of polymer adsorption onto the pigment can vary widely depending on polymer composition, pigment surface treatment, and solution properties such as pH and ionic strength. This investigation examines the effect of molecular weight on the adsorbed layer thickness and stabilizing action of polyacrylic acid dispersants. In order to understand the stabilization mechanism, a DLVO model was used in which the surface treatment layer of the pigment and the adsorbed layer thickness of the dispersant were taken into account. It was found that only this level of detail could account for the degree of stability found in pigment suspensions. Layer thickness and adsorption isotherms indicate that the dispersant molecules do not adsorb completely flat to the pigment surface but with enough loops and tails to provide some electrosteric stabilization.

Mark A Banash; Stuart G Croll

1999-01-01T23:59:59.000Z

113

Study of metallic materials for solid oxide fuel cell interconnect applications.  

SciTech Connect (OSTI)

Metallic interconnect acts as a gas separator and a gas distributor and therefore, it needs to function adequately in two widely different environments. The interconnect material will be exposed to air on one side and natural gas or coal-derived synthesis gas on the other side. The viable material for the interconnect application must be resistant not only to oxidation but also carburization in hydrocarbon containing low-oxygen environments. In addition, the scales that develop on the exposed surfaces must possess adequate electrical conductivity for them to function as current leads over long service life of the fuel cell. This report addresses five topics of interest for the development of metallic interconnects with adequate performance in fuel cells for long service life. The research conducted over the years and the conclusions reached were used to identify additional areas of research on materials for improved performance of components, especially metallic interconnects, in the complex fuel cell environments. This report details research conducted in the following areas: measurement of area specific electrical resistivity, corrosion performance in dual gas environments by experiments using alloy 446, long term corrosion performance of ferritic and austenitic alloys in hydrogen and methane-reformed synthesis fuel-gas environments, approaches to reduce the area resistance of metallic interconnect, and reduction of electrical resistivity of alumina scales on metallic interconnect. Based on the key requirements for metallic interconnects and the data developed on the corrosion behavior of candidate materials in meeting those requirements, several areas are recommended for further research to develop metallic interconnects with acceptable and reliable long-term performance in solid oxide fuel cells.

Natesan, K.; Zeng, Z.; Nuclear Engineering Division

2009-04-24T23:59:59.000Z

114

Chemisorption and anodic oxidation of aromatic molecules on Pd electrode surfaces: studies by UHV-EC-STM  

E-Print Network [OSTI]

yields an edge-vertical oriented diphenolic species. (iii) The extent of anodic oxidation of the chemisorbed organic strongly depends upon its initial orientation; only the flat-adsorbed species are oxidized completely to carbon dioxide. (iv...

Chen, Xiaole

2006-04-12T23:59:59.000Z

115

Spent-fuel special-studies progress report: probable mechanisms for oxidation and dissolution of single-crystal UO/sub 2/ surfaces  

SciTech Connect (OSTI)

Due to the complexity of the structural, microstructural and compositional characteristics of spent fuel, basic leaching and dissolution mechanisms were studied with UO/sub 2/ matrix material, specifically with single-crystal UO/sub 2/, to isolate individual contributory factors. The effects of oxidation and oxidation-dissolution were investigated in different oxidation conditions, such as in air, oxygenated solutions and deionized water containing H/sub 2/O/sub 2/. In addition, the effects of temperature on dissolution of UO/sub 2/ were studied in autoclaves at 75 and 150/sup 0/C. Also, oxidation and dissolution measurements were investigated via electrochemical methods to determine if those techniques could be applied to the characterization of leaching and dissolution of spent fuel in a hot cell. Finally, the effects of radiation were explored since the radiolysis of water may create a localized oxidizing condition at or near the spent fuel-solution interface, even in neutral or reducing conditions as commonly found in deep geological environments. The oxidation and oxidation-dissolution mechanisms for UO/sub 2/ are proposed as follows: The UO/sub 2/ surface is first oxidized in solution to form a UO/sub 2+x/ surface layer several angstroms thick. This oxidized surface has a high dissolution rate since the UO/sub 2+x/ reacts with the dissolved O/sub 2/, or H/sub 2/O/sub 2/, to form uranyl complex ions in a U(VI) state. As the uranyl ions exceed the solubility limits in solution, they become hydrolyzed to form solid deposits and suspended particles of UO/sub 3/ hydrates. The thickness and porosity of the deposited UO/sub 3/ hydrate surface-film is dependent on temperature, pH and deposition time. A long-term dissolution rate is then determined by the nature of the surface film, such as porosity, solubility and mechanical properties.

Wang, R.

1981-03-01T23:59:59.000Z

116

Study of oxygen reduction mechanism on Ag modified1 Sm1.8Ce0.2CuO4 cathode for solid oxide fuel cell2  

E-Print Network [OSTI]

to oxygen dissociation and diffusion process.26 KEYWORDS: Solid oxide fuel cell; Silver infiltrationStudy of oxygen reduction mechanism on Ag modified1 Sm1.8Ce0.2CuO4 cathode for solid oxide fuel cell2 3 4 Li-Ping Sun1 -- Hui Zhao1 -- Qiang Li1 -- Li-Hua Huo1 -- Jean-Paul Viricelle*2 --5 Christophe

Paris-Sud XI, Université de

117

Experimental study and kinetic model of monoethanolamine oxidative and thermal degradation for post-combustion CO2 capture  

Science Journals Connector (OSTI)

Abstract In the present work, a kinetic model is proposed for the prediction of amine solvent degradation in the post-combustion CO2 capture process. Solvent degradation combined to the emission of degradation products represents one of the main operational drawbacks of this process. It induces additional costs and it impacts the process efficiency and its environmental balance. In the present work, degradation is studied under accelerated conditions for the case of monoethanolamine solvent (MEA). The influence of the temperature and of the O2 and CO2 concentrations in the gas feed are studied, and their effect on the MEA loss and the emission of degradation products is quantified. Based on the experimental results, a kinetic model for both oxidative and thermal degradation of MEA is proposed and compared to previous attempts to model MEA degradation. The present kinetic model may be further used to develop a practical tool assessing solvent degradation in large-scale capture plants.

Grégoire Léonard; Dominique Toye; Georges Heyen

2014-01-01T23:59:59.000Z

118

Preparation of iron oxide thin film by metal organic deposition from Fe(III)-acetylacetonate: a study of photocatalytic properties  

Science Journals Connector (OSTI)

Iron oxide thin films have been deposited over fused quartz substrate by simple metal organic deposition from Fe-(III) acetylacetonate as the organic precursor. The decomposition of Fe-acetylacetonate is characterised by its distinct transition temperatures and thermogravimetric loss rates, which have been measured by thermal gravimetric analysis. As-deposited films were sintered in the temperature range 365–800°C and the structural changes of the iron oxide thin films as they transform into different crystalline phases have been studied by X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible absorption spectroscopy and scanning electron microscopy techniques. Mainly amorphous ?-Fe2O3 is formed at an annealing temperature of approximately 365–400°C, which transforms to ?-Fe2O3 phase with a further increase (600–800°C) in sintering temperature. The film sintered at 800°C consists of mainly crystalline ?-Fe2O3 phase, which shows photocatalytic degradation of an oxygenated aqueous solution of phenol upon visible light illumination.

Bonamali Pal; Maheshwar Sharon

2000-01-01T23:59:59.000Z

119

Mixture Preparation and Nitric Oxide Formation in a GDI Engine studied by Combined Laser Diagnostics and Numerical Modeling  

SciTech Connect (OSTI)

Through the combination of advanced imaging laser diagnostics with multi-dimensional computer models, a new understanding of the performance of direct-injection gasoline engines is pursuit. The work focuses on the fuel injection process, the breakup of the liquid into a fine spray and the mixing of the fuel with the in-cylinder gases. Non-intrusive laser diagnostics will be used to measure the spatial distribution of droplets and vaporized fuel with very high temporal resolution. These data along with temperature measurements will be used to validate a new spray breakup model for gasoline direct-injection. Experimental data on near wall fuel distributions will be used for comparison with a model that predicts the spray-wall interaction and the dynamics of the liquid film on the surface. Quantitative measurements of local nitric oxide concentrations inside the combustion chamber will provide a critical test for a numerical simulation of the nitric oxide formation process. This model is based on a modified flamelet approach and will be used to study the effects of exhaust gas recirculation.

Volker Sick; Dennis N. Assanis

2002-11-27T23:59:59.000Z

120

Conformational and Structural Relaxations of Poly(ethylene oxide) and Poly(propylene oxide) Melts: Molecular Dynamics Study of Spatial Heterogeneity, Cooperativity, and Correlated Forward-Backward Motion  

E-Print Network [OSTI]

Performing molecular dynamics simulations for all-atom models, we characterize the conformational and structural relaxations of poly(ethylene oxide) and poly(propylene oxide) melts. The temperature dependence of these relaxation processes deviates from an Arrhenius law for both polymers. We demonstrate that mode-coupling theory captures some aspects of the glassy slowdown, but it does not enable a complete explanation of the dynamical behavior. When the temperature is decreased, spatially heterogeneous and cooperative translational dynamics are found to become more important for the structural relaxation. Moreover, the transitions between the conformational states cease to obey Poisson statistics. In particular, we show that, at sufficiently low temperatures, correlated forward-backward motion is an important aspect of the conformational relaxation, leading to strongly nonexponential distributions for the waiting times of the dihedrals in the various conformational states

Michael Vogel

2007-10-30T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Solid oxide steam electrolysis for high temperature hydrogen production .  

E-Print Network [OSTI]

??This study has focused on solid oxide electrolyser cells for high temperature steam electrolysis. Solid oxide electrolysis is the reverse operation of solid oxide fuel… (more)

Eccleston, Kelcey L.

2007-01-01T23:59:59.000Z

122

An infrared spectroscopy study of carbon monoxide adsorption on. alpha. -chromia surfaces: Probing oxidation states of coordinatively unsaturated surface cations  

SciTech Connect (OSTI)

CO adsorption on thermoevacuated, H{sub 2}-reduced and O{sub 2}-treated {alpha}-chromia surfaces was studied by IR spectroscopy in the temperature range 77-298 K. Coordinatively unsaturated (cus) Cr{sup 3+} cation sites, probably in 3-coordinate and to a much lesser extent 5-coordinate states, are the adsorption sites on H{sub 2}-reduced {alpha}-Cr{sub 2}O{sub 3}. The surface containing excess oxygen also exposes cus Cr{sup 4+} and Cr{sup 5+} sites. An empirical procedure is described which permits the determination of oxidation state and coordination number of the cus surface sites. This procedure is based on a correlation between C-O stretching frequency and electric field strength exerted by the cation. The latter is calculated from Pauling's strength of the electrostatic bond and effective ionic radii, both of which take the cation coordination into account.

Zaki, M.I.; Knoezinger, H. (Universitaet Muenchen (West Germany))

1989-10-01T23:59:59.000Z

123

Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed-Bed and Entrained-Flow Reactor  

SciTech Connect (OSTI)

This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300-W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150?C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

Buitrago, Paula A; Morrill, Mike; Lighty, JoAnn S; Silcox, Geoffrey D

2014-08-20T23:59:59.000Z

124

Depth profile of oxide volume fractions of Zircaloy-2 in high-temperature steam: An in-situ synchrotron radiation study  

Science Journals Connector (OSTI)

Abstract To study the steam oxidation behavior of Zircaloy-2, a high-energy synchrotron X-ray diffraction technique was applied to perform an in-situ oxidation measurement. The depth profiles of oxide volume fractions were obtained at both 600 and 800 °C. Multiple layers, including ZrO2 scale, (? + ?) Zr matrix with ZrO2 incursions, and (? + ?) Zr matrix, were mapped according to the volume fraction of each phase. The volume fractions of these phases were observed to change gradually with different distances to the surface, without a sharp edge distinguishing each of the layers. The ZrO2 consisted of tetragonal and monoclinic crystal structures, which were observed to coexist with different ratios of volume fractions in depth. The higher amount of tetragonal ZrO2 observed in the very inner region of the oxidizing Zircaloy sample indicates that the tetragonal crystal structure is the ab initio phase type, in which new oxide molecules form at the metal–oxide interface.

Walid Mohamed; Di Yun; Kun Mo; Michael J. Pellin; Michael C. Billone; Jonathan Almer; Abdellatif M. Yacout

2014-01-01T23:59:59.000Z

125

Chemistry of carbonaceous aerosols : studies of atmospheric processing and OH-initiated oxidation  

E-Print Network [OSTI]

Carbonaceous aerosols are among the most prevalent yet least understood constituents of the atmosphere, particularly in urban environments. We have performed analyses of field samples and laboratory studies to probe the ...

Johnson, Kirsten S. (Kirsten Sue)

2008-01-01T23:59:59.000Z

126

Synchrotron PEEM and ToF-SIMS study of oxidized heterogeneous pentlandite, pyrrhotite and chalcopyrite  

Science Journals Connector (OSTI)

Polished surfaces of a naturally heterogeneous mineral sample containing chalcopyrite, pyrrhotite and pentlandite were studied using photoemission electron microscopy (PEEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), before and after exposure to aqueous solution.

Acres, R.G.

2010-07-28T23:59:59.000Z

127

Modeling of Solid Oxide Fuel Cell functionally graded electrodes and a feasibility study of fabrication techniques for functionally graded electrodes.  

E-Print Network [OSTI]

??Currently, Solid Oxide Fuel Cell (SOFC) electrodes have not been explored for optimization of graded electrodes and nonlinear functional grading. In this work, a complete… (more)

Flesner, Reuben

2009-01-01T23:59:59.000Z

128

Kinetic study of the reaction between nitric oxide and carbon monoxide catalyzed by clean polycrystalline platinum  

SciTech Connect (OSTI)

The kinetics of the platinum catalyzed reaction between NO and CO has been studied under conditions chosen to approximate those observed during operation of catalysts in automotive exhaust gas treatment applications. The catalysts were polycrystalline platinum foils and wires. The reaction was studied over a range of reactant partial pressures of 10 V Torr to 1 Torr and catalyst temperatures of 500 to 1500K. The steady-state kinetics results could not be fit by a simple Langmuir-Hinshelwood kinetic model over all experimental conditions studied. The kinetics at high coverage were most consistent with Langmuir-Hinshelwood kinetics assuming a bimolecular reaction between NO and CO as the rate-limiting step. At high temperature, the Langmuir-Hinshelwood assumption of fast adsorption-desorption equilibrium relative to the surface reaction rate was no longer appropriate and the mechanism of adsorption of NO had to be considered explicitly.

Klein, R.L.

1984-01-01T23:59:59.000Z

129

Numerical study of the partial oxidation of a coal particle in steam and dry air atmospheres  

Science Journals Connector (OSTI)

......and oxygen on particle combustion rate are approximately...modelling of particle combustion, studies on the in...coupled with a simple chemistry) on the influences...and velocity of the coal char particle, and...establishment of the combustion or gasification regimes......

M. Kestel; P. Nikrityuk; O. Hennig; C. Hasse

2012-02-01T23:59:59.000Z

130

Adsorption study of carbon oxides on reticulated vitreous carbon/RVC/plated with Ru electrode  

SciTech Connect (OSTI)

The adsorption of CO and CO2 on Ru/RVC and Ru/Pt electrodes has been studied by a potentiodynamic technique. It was shown that there are some differences between CO adsorption products on these two kinds of electrodes.CO2 adsorption on Ru electrode was not observed.

Czerwinski, A.

1987-04-01T23:59:59.000Z

131

Study of the potential oxidative stress induced by six solvents in the rat brain  

Science Journals Connector (OSTI)

The mechanisms of action involved in the neurotoxicity of solvents are poorly understood. In vitro studies have suggested that the effects of some solvents might be due to the formation of reactive oxygen species (ROS). This study assesses hydroxyl radical (OH) generation and measures malondialdehyde (MDA) levels in the cerebral tissue of rats exposed to six solvents (n-hexane, n-octane, toluene, n-butylbenzene, cyclohexane and 1,2,4-trimethylcyclohexane). Three of these solvents have been shown to generate ROS in studies carried out in vitro on granular cell cultures from rat cerebellum. We assessed OH production by quantifying the rate of formation of 3,4-dihydroxybenzoic acid using a trapping agent, 4-hydroxybenzoic acid, infused via the microdialysis probe, into the prefrontal cortex of rats exposed intraperitoneally to the solvents. Extracellular MDA was quantified in microdialysates collected from the prefrontal cortex of rats exposed, 6 h/day for ten days, to 1000 ppm of the solvents (except for n-butylbenzene, generated at 830 ppm) in inhalation chambers. Tissue levels of free and total MDA were measured in different brain structures for rats acutely (intraperitoneal route) and sub-acutely (inhalation) exposed to solvents. None of the six solvents studied increased the production of hydroxyl radicals in the prefrontal cortex after acute administration. Nor did they increase extracellular or tissue levels of MDA after 10 days’ inhalation exposure. On the other hand, a decrease in the concentrations of free MDA in brain structures was observed after acute administration of n-hexane, 1,2,4-trimethylcyclohexane, toluene and n-butylbenzene. Therefore, data of this study carried out in vivo did not confirm observations made in vitro on cell cultures.

Monique Chalansonnet; Nathalie Carabin; Stéphane Boucard; Frédéric Cosnier; Hervé Nunge; François Gagnaire

2013-01-01T23:59:59.000Z

132

Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x-ray photoelectron spectroscopy study  

E-Print Network [OSTI]

Carbon contamination and oxidation of Au surfaces under extreme ultraviolet radiation: An x 2012) Extreme ultraviolet (EUV) radiation-induced carbon contamination and oxidation of Au surfaces modification during EUV exposure. XPS analysis showed that total carbon contamination (C 1s peak

Harilal, S. S.

133

Laser Ablation Synthesis and Electron Transport Studies of Tin Oxide Nanowires**  

E-Print Network [OSTI]

and solar cells.[7±9] In addition, SnO2 thin films have been extensively studied and used as chemical demonstrated to work as sensitive UV and polarized UV detectors. A quartz tube furnace was used for our SnO2 of the furnace, and Si±SiO2 sub- strates covered with 20 nm gold catalytic clusters were placed in the middle

Zhou, Chongwu

134

Feasibility study of solid oxide fuel cell engines integrated with sprinter gas turbines: Modeling, design and control  

Science Journals Connector (OSTI)

Abstract Conventional recuperating solid oxide fuel cell (SOFC)/gas turbine (GT) system suffers from its poor dynamic capability and load following performance. To meet the fast, safe and efficient load following requirements for mobile applications, a sprinter SOFC/GT system concept is proposed in this paper. In the proposed system, an SOFC stack operating at fairly constant temperature provides the baseline power with high efficiency while the fast dynamic capability of the GT-generator is fully explored for fast dynamic load following. System design and control studies have been conducted by using an SOFC/GT system model consisting of experimentally-verified component models. In particular, through analysis of the steady-state simulation results, an SOFC operation strategy is proposed to maintain fairly constant SOFC power (less than 2% power variation) and temperature (less than 2 K temperature variation) over the entire load range. A system design procedure well-suited to the proposed system has also been developed to help determining component sizes and the reference steady-state operation line. In addition, control analysis has been studied for both steady-state and transient operations. Simulation results suggest that the proposed system holds the promise to achieve fast and safe transient operations by taking full advantage of the fast dynamics of the GT-generator.

Zhenzhong Jia; Jing Sun; Herb Dobbs; Joel King

2015-01-01T23:59:59.000Z

135

Study of mercury oxidation by a selective catalytic reduction catalyst in a pilot-scale slipstream reactor at a utility boiler burning bituminous coal  

SciTech Connect (OSTI)

One of the cost-effective mercury control technologies in coal-fired power plants is the enhanced oxidation of elemental mercury in selective catalytic reduction (SCR) followed by the capture of the oxidized mercury in the wet scrubber. This paper is the first in a series of two in which the validation of the SCR slipstream test and Hg speciation variation in runs with or without SCR catalysts inside the SCR slipstream reactor under special gas additions (HCl, Cl{sub 2}, SO{sub 2}, and SO{sub 3}) are presented. Tests indicate that the use of a catalyst in a SCR slipstream reactor can achieve greater than 90% NO reduction efficiency with a NH{sub 3}/NO ratio of about 1. There is no evidence to show that the reactor material affects mercury speciation. Both SCR catalysts used in this study exhibited a catalytic effect on the elemental mercury oxidation but had no apparent adsorption effect. SCR catalyst 2 seemed more sensitive to the operational temperature. The spike gas tests indicated that HCl can promote Hg{sup 0} oxidation but not Cl{sub 2}. The effect of Cl{sub 2} on mercury oxidation may be inhibited by higher concentrations of SO{sub 2}, NO, or H{sub 2}O in real flue-gas atmospheres within the typical SCR temperature range (300-350{sup o}C). SO{sub 2} seemed to inhibit mercury oxidation; however, SO{sub 3} may have some effect on the promotion of mercury oxidation in runs with or without SCR catalysts. 25 refs., 9 figs., 2 tabs.

Yan Cao; Bobby Chen; Jiang Wu; Hong Cui; John Smith; Chi-Kuan Chen; Paul Chu; Wei-Ping Pan [Western Kentucky University, Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology (ICSET)

2007-01-15T23:59:59.000Z

136

New insight into artifactual phenomena during in vitro toxicity assessment of engineered nanoparticles: study of TNF-adsorption on alumina oxide nanoparticle  

E-Print Network [OSTI]

nanoparticles: study of TNF- adsorption on alumina oxide nanoparticle Mélanie Pailleuxa,b , Delphine Boudarda Biomolecules can be adsorbed on nanoparticles (NP) and degraded during in vitro toxicity assays: boehmite nanoparticles; toxicity; TNF- adsorption; TNF- degradation; correction curve hal-00799129,version1

Boyer, Edmond

137

Ab Initio Study of the Interaction of Water with Cluster Models of the Aluminum Terminated (0001) r-Aluminum Oxide Surface  

E-Print Network [OSTI]

Ab Initio Study of the Interaction of Water with Cluster Models of the Aluminum Terminated (0001) r-Aluminum to hydroxylation of the aluminum terminated surface, the two water process was found to be the most exothermic, occurring within 10-2 s. I. Introduction As one of the most important ceramic materials, R-aluminum oxide

Schlegel, H. Bernhard

138

Infrared spectroscopic studies of carbon monoxide adsorbed on a series of silica-supported copper catalysts in different oxidation states  

SciTech Connect (OSTI)

Infrared spectroscopy has been used to study the adsorption of carbon monoxide (358-493 K, 0.1-20 kPa) on four copper-on-silica (2-10 wt% Cu) catalysts prepared by the ion-exchange technique. The measurements are made for each sample in three different states: unreduced (predominantly Cu{sup 2+}), and reduced (Cu{sup 0}), and partially reoxidized in nitrous oxide (Cu{sup +}). On unreduced samples, a major absorption band between 2127 and 2132 cm{sup {minus}1} due to CO adsorbed on small CuO particles and a weak band at 2199 cm{sup {minus}1} due to CO on isolated Cu{sup 2+} ions incorporated in the silica surface have been identified. The former adsorption obeys a Langmuir isotherm with a heat of adsorption of 29 kJ/mol independent of CuO particle size and surface coverage. After catalyst reduction, the major absorption band lies between 2090 and 2113 cm{sup {minus}1} and arises from CO linearly bound to very small (1- to 5-nm) copper metal clusters. The observed frequency shifts indicate the presence of steps and terraces similar to low index Cu planes in very small particles (1- to 2-nm), and the presence of similar higher index Cu planes on larger clusters (2- to 5-nm). The absorption is described by a Freundlich isotherm with the heat of CO adsorption decreasing with coverage from 50 to 22 kJ/mol on bigger particles but more constant (27 to 22 kJ/mol) on small particles. A surface copper/CO atomic ratio increasing from 5 to 12 is established at equilibrium saturation between 358 and 493 K using extinction coefficients determined in this study. In the reduced catalysts, a weakly adsorbed ({Delta}H{sub a} = {minus}20 kJ/mol) species assigned to CO bound to isolated Cu{sup +} ions is also found and absorbs at 2175 cm{sup {minus}1}. The frequency of this band does not vary with catalyst loading and is not affected by reoxidation of the catalyst in nitrous oxide.

Kohler, M.A.; Wainwright, M.S.; Trimm, D.L.; Cant, N.W. (Macquarie Univ., New South Wales (Australia) Univ. of South Wales (Australia))

1989-05-01T23:59:59.000Z

139

Metal Oxides  

Science Journals Connector (OSTI)

Metal oxides are the class of materials having the widest application in gas sensors. This chapter presents information related to the application of various metal oxides in gas sensors designed on different p...

Ghenadii Korotcenkov

2013-01-01T23:59:59.000Z

140

Study of the Nucleation and Growth of YBCO on Oxide Buffered Metallic Tapes  

SciTech Connect (OSTI)

The CRADA collaboration concentrated on developing the scientific understanding of the factors necessary for commercialization of high temperature superconductors (HTS) based on the YBCO coated conductor technology for electric power applications. The project pursued the following objectives: 1. Establish the correlations between the YBCO nuclei density and the properties of the CeO{sub 2} layer of the RABiTS{trademark} template; 2. Compare the nucleation and growth of e-beam and MOD based precursors on the buffered RABiTS{trademark} templates and clarify the materials science behind the difference; and 3. Explore routes for the optimization of the nucleation and growth of thick film MOD precursors in order to achieve high critical current densities in thick films. The CRADA work proceeded in two steps: 1. Detailed characterization of epitaxial ceria layers on “model” substrates, such as (001) YSZ and on RABiTS tapes; and 2. Study of YBCO nucleation on well-defined substrates and on long-length RABiTS.

Solovyov, Vyacheslav

2009-04-10T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Oxidation state of manganese in zinc pyrophosphate: Probed by luminescence and EPR studies  

SciTech Connect (OSTI)

Zn{sub 2}P{sub 2}O{sub 7}: Mn was synthesized by wet chemical route and characterized by X-ray diffraction (XRD), photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques. Photoluminescence spectrum shows two bands, one at 500 nm (green emission), which is attributed to the {sup 4}T{sub 1}({sup 4}G)-{sup 6}A{sub 1}({sup 6}S) transition of Mn{sup 2+} and other centered at 686 nm (red emission) is attributed to the electronic transition between {sup 2}E and {sup 4}A{sub 2} of Mn{sup 4+} accompanied with vibronic transitions. EPR spectroscopic studies also confirmed the presence of both Mn2+ and Mn4+ ions in zinc pyrophosphate with difference in the number of fine transitions and g values (Mn{sub 4+}, S=3/2, three fine transitions and g < 2.00; Mn{sup 2+} S=5/2, five fine transitions and g=2.00).Mn{sup 2+} is attributed to presence of Mn at 6-ccordinated Zn{sup 2+} site whereas Mn{sup 4+} is due to presence substitution of Mn{sup 4+} at Zn{sup 2+} site thereby invoking charge compensation by presence of interstitial oxygen ions around Mn{sup 4+} ion or due to substitution of manganese at distorted 5-coordinated zinc site.

Gupta, Santosh K., E-mail: santoshg@barc.gov.in; Kadam, R. M., E-mail: santoshg@barc.gov.in; Natarajan, V., E-mail: santoshg@barc.gov.in; Godbole, S. V., E-mail: santoshg@barc.gov.in [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

2014-04-24T23:59:59.000Z

142

On-line electrochemistry/electrospray mass spectrometry: Studies of oxidation of polycyclic aromatic hydrocarbons (PAHs)  

SciTech Connect (OSTI)

Studies of on-line coupling of electrochemistry with mass spectrometry, i.e., {open_quotes}electrochemical mass spectrometry{close_quotes} (EC/MS) date back to work by Bruckenstein et al. in the 1970`s. In these and other early experiments, porous working electrodes or permeable membranes were usually used as the interface between the cell and the MS ionization source which exclusively employed electron ionization (EI). As a result, only volatile products of electrochemical reactions could be detected by the mass line electrochemistry/mass spectroscopy was the coupling of an mass spectrometer (EC/TS/MS) reported by Hambitzer and g an aqueous ammonium acetate thermospray buffer solution, all detected or ammoniated species in the positive ion mode or as deprotonated or acetate adduct species in the negative ion mode. Radical cations or anions were not detected. Although {open_quotes}electrochemically assisted electrospray mass spectrometry{close_quotes} has been progressing for a few years, chiefly due to the pioneering efforts of Van Berkel and coworkers, on-line coupling electrochemistry with electrospray mass spectrometry (EC/ESMS) is still a developing area because of the experimental difficulties involved, such as high voltage hazard to the electrochemistry hardware (e.g. potentiostat), and MS signal suppression caused by the presence of high concentrations of supporting electrolytes. We report the coupling of an electrochemical device on-line with electrospray mass spectrometry (EC/ESMS) to extend the potential of ESMS to detect non-polar neutral compounds, and to monitor and identify intermediates and products generated by electrochemical reactions.

Xu, Xiaoming; Lu, Wenzhe; Cole, R.B. [Univ. of New Orleans, LA (United States)] [and others

1995-12-31T23:59:59.000Z

143

Final purification of synthetic olive oil mill wastewater treated by chemical oxidation using ion exchange: Study of operating parameters  

Science Journals Connector (OSTI)

Abstract In this research work, ion exchange (IE) is presented as a suitable option for purification of olive oil mill wastewater (OMW) previously treated by means of a secondary treatment (OMWST). This pretreatment consisted in Fenton-like oxidation process, followed by coagulation–flocculation and filtration through olive stones. The parametric requirements for drinking water production or at least for public waterways discharge were achieved using a combination of two IE columns working in series at bench scale. The IE resins used in this study were Dowex Marathon C and Amberlite IRA-67. The effect of contact time, operating temperature and flow rate on simultaneous removal of sodium, total iron, chloride and phenols (the major pollutant species in OMWST) were investigated. Removal percentages of sodium, chloride and total iron increased with incrementing the contact time. Equilibrium was obtained in about 30 min for all ions and ion concentrations values determined were lower than the maximum levels for drinking water standards. On the other hand, adsorption efficiencies of sodium, total iron and chloride ions were found to be not considerably affected by the operating temperature. The highest phenols removal percentage (around 100%) was obtained in the first minutes for 298 K and 10 L/h.

M.D. Víctor-Ortega; J.M. Ochando-Pulido; G. Hodaifa; A. Martinez-Ferez

2014-01-01T23:59:59.000Z

144

In-situ X-ray photoelectron spectroscopy studies of water on metals and oxides at ambient conditions  

SciTech Connect (OSTI)

X-ray photoelectron spectroscopy (XPS) is a powerful tool for surface and interface analysis, providing the elemental composition of surfaces and the local chemical environment of adsorbed species. Conventional XPS experiments have been limited to ultrahigh vacuum (UHV) conditions due to a short mean free path of electrons in a gas phase. The recent advances in instrumentation coupled with third-generation synchrotron radiation sources enables in-situ XPS measurements at pressures above 5 Torr. In this review, we describe the basic design of the ambient pressure XPS setup that combines differential pumping with an electrostatic focusing. We present examples of the application of in-situ XPS to studies of water adsorption on the surface of metals and oxides including Cu(110), Cu(111), TiO2(110) under environmental conditions of water vapor pressure. On all these surfaces we observe a general trend where hydroxyl groups form first, followed by molecular water adsorption. The importance of surface OH groups and their hydrogen bonding to water molecules in water adsorption on surfaces is discussed in detail.

Salmeron, Miquel; Yamamoto, S.; Bluhm, H.; Andersson, K.; Ketteler, G.; Ogasawara, H.; Salmeron, M.; Nilsson, A.

2007-10-29T23:59:59.000Z

145

Theoretical study of defect formation during the initial stages of native-oxide growth on GaSb (001)  

SciTech Connect (OSTI)

The formation of defects during the initial stages of native-oxide growth on the GaSb (001)-?(4?×?3) surface has been studied computationally using spin-unrestricted density functional theory. It is found that insertion into a Ga-Sb adatom dimer to form a peroxo Ga-O-O-Sb bridge is the most energetically favorable process with insertion into Ga-Sb back-bonds being somewhat less so. A Ga-O-O-Ga bridge between dimers is also favorable, but Sb-O-O-Sb bridges show little if any stability. In the course of analyzing molecular adsorption, a particularly reactive site has been identified that leads to O{sub 2} dissociation with little or no barrier. This process is initiated in the vicinity of an Sb-Sb dimer in the terminating layer and leads to sub-surface Ga and Sb defect sites (i.e., coordinatively unsaturated atoms) and to strained Ga-Sb bonds that may be susceptible to further O{sub 2} attack. However, the defects formed in these reactions do not produce states in the gap.

Bermudez, V. M., E-mail: victor.bermudez@nrl.navy.mil [Electronics Science and Technology Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States)

2014-04-07T23:59:59.000Z

146

A comparative study of polyethylene oxide/nanoclay composite preparation via supercritical carbon dioxide and melt processing  

Science Journals Connector (OSTI)

The efficacy of supercritical carbon dioxide (ScCO2...) treatment compared with conventional melt processing methods in preparing nanoclay composites from poly(ethylene oxide) (PEO)...2 processing yielded more ho...

Gordon Armstrong; Keith Fortune

2007-10-01T23:59:59.000Z

147

Studies on toxicity of aluminum oxide (Al2O3) nanoparticles to microalgae species: Scenedesmus sp. and Chlorella sp.  

Science Journals Connector (OSTI)

In view of increasing commercial applications of metal oxide nanoparticles their toxicity assessment becomes important. Alumina (Al2O3) nanoparticles have wide range of applications in industrial as well as perso...

I. Mohammed Sadiq; Sunandan Pakrashi; N. Chandrasekaran…

2011-08-01T23:59:59.000Z

148

A study of Mo-modified Pd/MWCNT catalysts for ethanol oxidation in the alkaline solution  

Science Journals Connector (OSTI)

The effect of the modification of Pd-based electrocatalysts by molybdenum on the catalytic performance toward ethanol oxidation in the alkaline solution is investigated. ... the poison resistance of Pd-based nano...

Weimin Chen; Yu Zhang

2014-02-01T23:59:59.000Z

149

Si(001) vicinal surface oxidation in O2: Angle-resolved Si 2p core-level study using synchroton radiation  

Science Journals Connector (OSTI)

The aim of this work is to determine if, after oxidation in pure O2, a vicinal surface Si(001) miscut 5° towards the [110] direction, exhibits a preferential SiO2 formation on the [110] ledges. In a first stage, combining XPS (X-ray photoelectron spectroscopy) and LEED (low-energy electron diffraction) available in an auxiliary chamber, we examine the cleaning conditions leading to a non-faceted stepped Si surface with dominant (2 × 1) single domains. This surface preparation is reproduced in the synchroton facility chamber where ARPR-single-resolved photoemission spectroscopy) is performed: after cleaning the Si surface and studying the starting situation (san- states, initial contamination), an ultra-thin oxide film (? 1.5 × 1015 oxidised Si atoms/cm2) is grown at 785–800°C, under Torr of oxygen. The absence of anisotropy in the ARPES emission of the Si 2p core levels taken at the minimum electron escape depth (hv=130eV), points to no extra-growth of the oxide on the ledges. The in-depth distribution of the oxide states seems to be homogeneous, within the sensitivity of the probe. On the other hand, after partial thermal desorption of the ultra-thin oxide film in vacuum, a strong anisotropy in the emission of electrons from SiO2 is seen in areas where oxide patches coexist with bare silicon. It is shown that this ensues from a significant step bunching and (111) faceting of the surface. A correlation is made with SEM (scanning electron microscopy) images of the surface. The problem of step bunching, inasmuch as it can alter the interpretation of shadowing effects, is emphasized.

F. Rochet; H. Roulet; G. Dufour; S. Carniato; C. Guillot; N. Barrett; M. Froment

1992-01-01T23:59:59.000Z

150

Oxidative Degradation of Monoethanolamine  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Oxidative Degradation of Monoethanolamine Oxidative Degradation of Monoethanolamine Susan Chi Gary T. Rochelle* (gtr@che.utexas.edu, 512-471-7230) The University of Texas at Austin Department of Chemical Engineering Austin, Texas 78712 Prepared for presentation at the First National Conference on Carbon Sequestration, Washington, DC, May 14-17, 2001 Abstract Oxidative degradation of monoethanolamine (MEA) was studied under typical absorber condition of 55°C. The rate of evolution of NH 3 , which was indicative of the overall rate of degradation, was measured continuously in a batch system sparged with air. Dissolved iron from 0.0001 mM to 1 mM yields oxidation rates from 0.37 to 2 mM/hr in MEA solutions loaded with 0.4 mole CO 2 / mole MEA. Ethylenediaminetetraacetic acid (EDTA) and N,N-bis(2- hydroxyethyl)glycine effectively decrease the rate of oxidation in the presence of iron by 40 to

151

Electronic structure and reactivity in water splitting of the iron oxide dimers and their hexacarbonyls: A density functional study  

SciTech Connect (OSTI)

The iron oxide dimers (FeO){sub 2} and their peroxide isomers are studied with the B3LYP density functional as bare clusters and as hexacarbonyls. Among the bare clusters the planar four-member ring structures are more stable than the non-planar ones and the rhombic dioxide Fe{sub 2}O{sub 2} with antiferromagnetically ordered electrons on iron centers is the global minimum. Water adsorption on the bare diiron dioxide is exothermic, but dissociation does not occur. Carbonylation favors a non-planar Fe{sub 2}O{sub 2} ring for both the dioxides and the peroxides and high electron density at the Fe centers is induced, evidenced by the natural charge distribution, the high proton affinity, and the values of global electronegativity and hardness. The iron dioxide hexacarbonyl Fe{sub 2}O{sub 2}(CO){sub 6} is diamagnetic in the state of the global minimum. It is separated from the next low-lying triplet state by a small energy gap of 0.22 eV. Time-dependent density functional theory methods were applied to examine electron excitations from the ground state to the low-lying triplet states in the hexacarbonyls and their adsorption complexes with water. Singlet-to-triplet state excitations occur via ligand-to-metal charge transfer in the hexacarbonyls; in the adsorption complexes excitations from the oxygen lone pairs to the adsorption center also occur and they appear in the IR-visible region. The lowest energy singlet and triplet state reaction paths for water splitting were followed. On the singlet potential energy surface (PES), water splitting is spontaneous, while for the triplet PES an activation barrier of 14.1 kJ mol{sup ?1} was determined.

Uzunova, Ellie L., E-mail: ellie@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria); Mikosch, Hans [Institute for Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/E164-EC, 1060 Vienna (Austria)] [Institute for Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/E164-EC, 1060 Vienna (Austria)

2014-01-14T23:59:59.000Z

152

Ellipsometric, nuclear reaction analysis and high energy ion shadowing/blocking study of the oxidation of Fe(100)  

Science Journals Connector (OSTI)

The change in the ellipsometric parameter ? (??o) upon oxidation of various Ni and Fe single crystal surfaces has been related to absolute amounts of adsorbed oxygen, using nuclear reaction analysis (NRA). A linear relationship between ??o and oxygen uptake is found for coverages up to at least 1016 atoms/cm2. Using high energy ion scattering in combination with shadowing and blocking (HEIS-SB), the number of disordered Fe atoms on Fe(100) surfaces exposed to 0–2000 L O2 have been determined. Combining calibrated ellipsometry and HEIS-SB results we find that an oxide layer with average stoichiometry Fe0.95±0.07O forms. The oxide layer formed after exposure to 2000 L involves (5.0±0.5) × 1015 Fe atoms/cm2 which corresponds to 4.1±0.4 Fe(100) monolayers.

G.W.R. Leibbrandt; S. Deckers; M. Wiegel; F.H.P.M. Habraken

1991-01-01T23:59:59.000Z

153

Ellipsometric, nuclear reaction analysis and high energy ion shadowing/blocking study of the oxidation of Fe(100)  

Science Journals Connector (OSTI)

The change in the ellipsometric parameter ? (??o) upon oxidation of various Ni and Fe single crystal surfaces has been related to absolute amounts of adsorbed oxygen, using nuclear reaction analysis (NRA). A linear relationship between ??o and oxygen uptake is found for coverages up to at least 1016 atoms/cm2. Using high energy ion scattering in combination with shadowing and blocking (HEIS-SB), the number of disordered Fe atoms on Fe(100) surfaces exposed to 0–2000 L O2 have been determined. Combining calibrated ellipsometry and HEIS-SB results we find that an oxide layer with average stoichiometry Fe0.95 ± 0.07O forms. The oxide layer formed after exposure to 2000 L involves (5.0 ± 0.5) × 1015 Fe atoms/cm2 which corresponds to 4.1 ± 0.4 Fe(100) monolayers.

G.W.R Leibbrandt; S Deckers; M Wiegel; F.H.P.M Habraken

1991-01-01T23:59:59.000Z

154

Comparative study of the alloying effect on the initial oxidation of Cu-Au(100) and Cu-Pt(100)  

SciTech Connect (OSTI)

Using in situ transmission electron microscopy, we show that the oxidation of the Cu-Au(100) results in the formation of Cu{sub 2}O islands that deeply embed into the Cu-Au substrate while the oxidation of the Cu-Pt(100) leads to the formation of Cu{sub 2}O islands that highly protrude above the Cu-Pt substrate. Their difference is attributed to the different mobilities of Pt and Au in the Cu base alloys for which the sluggish mobility of Pt in Cu results in trapped Pt atoms at the oxide/alloy interface while the faster mobility of Au in Cu leads to enhanced rehomogenization of the alloy composition.

Luo, Langli; Zhou, Guangwen, E-mail: gzhou@binghamton.edu [Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902 (United States); Kang, Yihong [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States); Yang, Judith C. [Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States); Su, Dong; Stach, Eric A. [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973 (United States)

2014-03-24T23:59:59.000Z

155

A kinetic and adsorption study of CO oxidation over unsupported fine gold powder and over gold supported on titanium dioxide  

SciTech Connect (OSTI)

The catalytic oxidation of CO with O{sub 2} and adsorption of CO{sub 2} and O{sub 2} on Au deposited on TiO{sub 2} (AuTiO{sub 2}, mean diameter of gold particles 3.5 nm), TiO{sub 2}, and unsupported Au powder (mean diameter 76 nm) have been investigated by using a closed recirculation reaction system. The catalytic oxidation of CO with O{sub 2} on Au/TiO{sub 2} measured at 253--293 K proceeded very rapidly. In the same temperature range, fine gold powder was catalytically active, while TiO{sub 2} alone was entirely inactive for the oxidation. The rate constant of CO oxidation per unit of surface area of gold was larger by two orders of magnitude for Au/TiO{sub 2} than for Au powder. Adsorption of CO and CO{sub 2} occurred almost instantaneously and reversibly on preoxidized Au/TiO{sub 2}, whereas a slow increase in the O{sub 2} pressure was observed at 273 K in the absence of evacuation. A similar increase of O{sub 2} pressure was observed from oxidized TiO{sub 2}, but Au powder did not show any increase. The increase was ascribed to the desorption of weakly adsorbed O{sub 2} on the support surface of Au/TiO{sub 2}. The rate of reduction of preoxidized Au/TiO{sub 2} with CO almost corresponded to the increase in the O{sub 2} pressure and was far smaller than the rate of the catalytic oxidation of CO with O{sub 2} on the catalyst, indicating that molecular oxygen weakly adsorbed on the support surface of Au/TiO{sub 2} contributes only partly to the catalytic oxidation of CO. During the oxidation, O{sub 2} in the gas phase may be directly activated on the surface of deposited gold particles and/or on the very narrow perimeter interface between the gold and the support.

Iizuka, Yasuo; Tode, Toshihisa; Takao, Toshiaki; Yatsu, Kenichiro; Takeuchi, Toshiaki; Tsubota, Susumu; Haruta, Masatake

1999-10-01T23:59:59.000Z

156

Graphene oxide oxidizes stannous ions to synthesize tin sulfidegraphene nanocomposites with small crystal size for high performance lithium ion  

E-Print Network [OSTI]

Graphene oxide oxidizes stannous ions to synthesize tin sulfide­graphene nanocomposites with small September 2012 DOI: 10.1039/c2jm34864k This study reports a novel strategy of preparing graphene composites by employing graphene oxide as precursor and oxidizer. It is demonstrated that graphene oxide can oxidize

Cao, Guozhong

157

Development of the ReaxFF reactive force field for mechanistic studies of catalytic selective oxidation processes on BiMoOx  

E-Print Network [OSTI]

report the use of ReaxFF to study the activation and conversion of propene to acrolein by various metal acrolein. The propene reations on V2O5 occur at lower temperatures than on Bi2O3 or Bi2Mo3O12. The results-metal­ oxide (MMO) catalysts, accounts for the majority of the 8 billion pounds of acrolein produced annually

van Duin, Adri

158

FTIR study of carbon monoxide oxidation and scrambling at room temperature over copper supported on ZnO and TiO{sub 2} No. 1  

SciTech Connect (OSTI)

An FTIR and quadrupole mass spectroscopic study of CO adsorption and oxidation with {sup 16}O{sub 2} and {sup 18}O{sub 2} on copper supported on ZnO and TiO{sub 2} is presented. The experimental results indicate that CO is adsorbed on the metallic particles dispersed on both oxides on two kinds of sites, on the normal terrace sites and on sites at the borderline of the particles. Moreover, on titania, a band at 2126 cm{sup -1}, assigned to CO adsorbed on isolated Cu atoms and/or on two-dimensional small clusters, is detected. A frequency shift of the bands of CO adsorbed on the metallic particles observed in the CO-O{sub 2} coadsorption experiments and the occurrence of a scrambling reaction between CO and {sup 18}O{sub 2} reveal that on all these samples, there are metallic sites which are able to adsorb at the same time oxygen atoms and carbon monoxide. Carbon dioxide and carbonate-like species are formed: the asymmetric stretching frequencies of CO{sub 2} and the quadrupole mass spectroscopic analysis reveal that with {sup 18}O{sub 2}, different isotopic molecular CO{sub 2}`s are formed, while the carbonate-like species have the same frequencies of those produced in {sup 16}O{sub 2}. Moreover, these species are completely lacking in the absence of oxygen in the gas phase. The experimental results indicate the there are, on these samples, two independent pathways for the CO oxidation, a direct oxidation of CO at the surface of the metallic particles and an induced oxidation with the surface lattice oxygen species of the supports. 46 refs., 8 figs.

Baccuzzi, F.; Chiorino, A. [Universita di Torino (Italy)] [Universita di Torino (Italy)

1996-02-29T23:59:59.000Z

159

PHYSICAL REVIEW B 86, 245429 (2012) Ab initio atomistic thermodynamics study of the early stages of Cu(100) oxidation  

E-Print Network [OSTI]

- cluding methane synthesis,1­3 catalytic conversion of nitrogen oxides,4 water-gas shift,5,6 and preventing for oxygen chemical potentials below the nucleation limit of Cu2O, they are likely to exist due to kinetic

McGaughey, Alan

160

Electrochemical Oxidation of Size-Selected Pt Nanoparticles Studied Using in Situ High-Energy-Resolution Xray Absorption Spectroscopy  

E-Print Network [OSTI]

technological interest, since the performance and long-term stability of low-temperature fuel cells are largely of the chemical state of Pt under oxidizing conditions is needed for an understanding of the degradation of fuel cell performance during long-term operation, due primarily to the loss of electrocatalytic surface area

Kik, Pieter

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Viscoelastic Properties, Ionic Conductivity, and Materials Design Considerations for Poly(styrene-b-ethylene oxide-b-styrene)-Based Ion Gel Electrolytes  

SciTech Connect (OSTI)

The viscoelastic properties and ionic conductivity of ion gels based on the self-assembly of a poly(styrene-b-ethylene oxide-b-styrene) (SOS) triblock copolymer (M{sub n,S} = 3 kDa, M{sub n,O} = 35 kDa) in the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMI][TFSA]) were investigated over the composition range of 10-50 wt % SOS and the temperature range of 25-160 C. The poly(styrene) (PS) end-blocks associate into micelles, whereas the poly(ethylene oxide) (PEO) midblocks are well-solvated by this ionic liquid. The ion gel with 10 wt % SOS melts at 54 C, with the longest relaxation time exhibiting a similar temperature dependence to that of the viscosity of bulk PS. However, the actual values of the gel relaxation time are more than 4 orders of magnitude larger than the relaxation time of bulk PS. This is attributed to the thermodynamic penalty of pulling PS end-blocks through the PEO/[EMI][TFSA] matrix. Ion gels with 20-50 wt % SOS do not melt and show two plateaus in the storage modulus over the temperature and frequency ranges measured. The one at higher frequencies is that of an entangled network of PEO strands with PS cross-links; the modulus displays a quadratic dependence on polymer weight fraction and agrees with the prediction of linear viscoelastic theory assuming half of the PEO chains are elastically effective. The frequency that separates the two plateaus, {omega}{sub c}, reflects the time scale of PS end-block pull-out. The other plateau at lower frequencies is that of a congested micelle solution with PS cores and PEO coronas, which has a power law dependence on domain spacing similar to diblock melts. The ionic conductivity of the ion gels is compared to PEO homopolymer solutions at similar polymer concentrations; the conductivity is reduced by a factor of 2.1 or less, decreases with increasing PS volume fraction, and follows predictions based on a simple obstruction model. Our collective results allow the formulation of basic design considerations for optimizing the mechanical properties, thermal stability, and ionic conductivity of these gels.

Zhang, Sipei; Lee, Keun Hyung; Sun, Jingru; Frisbie, C. Daniel; Lodge, Timothy P. (UMM)

2013-03-07T23:59:59.000Z

162

Thermodynamic stability of LaMnO3 and its competing oxides: A hybrid density functional study of an alkaline fuel cell catalyst  

Science Journals Connector (OSTI)

The phase stability of LaMnO3 with respect to its competing oxides is studied using hybrid-exchange density functional theory (DFT) as implemented in crystal09. The underpinning DFT total-energy calculations are embedded in a thermodynamic framework that takes optimal advantage of error cancellation within DFT. It has been found that by using the ab initio thermodynamic techniques described here, the standard Gibbs formation energies can be calculated to a significantly greater accuracy than was previously reported (a mean error of 1.6% with a maximum individual error of ?3.0%). This is attributed to both the methodology for isolating the chemical potentials of the reference states, as well as the use of the Becke, three-parameter, Lee-Yang-Parr (B3LYP) functional to thoroughly investigate the ground-state energetics of the competing oxides.

E. A. Ahmad; L. Liborio; D. Kramer; G. Mallia; A. R. Kucernak; N. M. Harrison

2011-08-30T23:59:59.000Z

163

Rapid thermal oxidation of silicon in mixtures of oxygen and nitrous oxide  

SciTech Connect (OSTI)

Oxidation in nitrous oxide by conventional hot wall furnace processing and by rapid thermal oxidation (RTO) has been a subject of much interest in recent years. RTO is a fundamentally different process than furnace oxidation, however, and the full effects of this type of processing on the oxidation kinetics are not well understood. Oxidation of silicon by RTO at a variety of pressures, temperatures, and oxidation gas mixtures has been studied. Although at lower temperatures (< 850 C) the atmospheric pressure oxidation rate in nitrous oxide is very close to that in oxygen, at higher temperatures the oxidation rate in nitrous oxide is much lower than that in oxygen. At lower pressures in a RTO process, the oxidation rate in nitrous oxide is higher than that in oxygen. The effect of the nitrogen incorporated in the oxide acting as a diffusion barrier has been proposed as the mechanism of temperature dependence for atmospheric pressure oxidation in nitrous oxide. This does not explain the effects seen at lower pressure,s however, The authors propose that some of the intermediate species produced in the decomposition of nitrous oxide into molecular nitrogen, molecular oxygen, and nitric oxide play a role in the initial stages of oxidation by RTO in nitrous oxide.

Grant, J.M.; Karim, Z. [Sharp Microelectronics Technology, Inc., Camas, WA (United States)

1996-12-01T23:59:59.000Z

164

An In-Situ XAS Study of the Structural Changes in a CuO-CeO2/Al2O3 Catalyst during Total Oxidation of Propane  

SciTech Connect (OSTI)

A CuOx-CeOx/Al2O3 catalyst was studied with in-situ transmission Cu K XAS for the total oxidation of propane as model reaction for the catalytic elimination of volatile organic compounds. The local Cu structure was determined for the catalyst as such, after pre-oxidation and after reduction with propane. The catalyst as such has a local CuO structure. No structural effect was observed upon heating in He up to 600 deg. C or after pre-oxidation at 150 deg. C. A full reduction of the Cu2+ towards metallic Cu0 occurred, when propane was fed to the catalyst. The change in local Cu structure during propane reduction was followed with a time resolution of 1 min. The {chi}(k) scans appeared as linear combinations of start and end spectra, CuO and Cu structure, respectively. However, careful examination of the XANES edge spectra indicates the presence of a small amount of additional Cu1+ species.

Silversmith, Geert; Poelman, Hilde; Poelman, Dirk; Gryse, Roger de [Ghent University, Department of Solid State Sciences, Krijgslaan 281 S1, B-9000 Gent (Belgium); Olea, Maria; Balcaen, Veerle; Heynderickx, Philippe; Marin, Guy B. [Ghent University, Laboratorium voor Petrochemische Techniek, Krijgslaan 281 S5, B-9000 Gent (Belgium)

2007-02-02T23:59:59.000Z

165

Comparative study of the reactions of metal oxides and carbonates with H{sub 2}S and SO{sub 2}. Final technical report, September 1990--February 1994  

SciTech Connect (OSTI)

The primary objective of this project had been the investigation of the effects of pore structure on the capacity of porous metal oxides for removal of gaseous pollutants from flue gases of power plants (SO{sub 2}) and hot coal gas (primarily H{sub 2}S). Porous calcines obtained from natural precursors (limestones and dolomites) and sorbents based on zinc oxide were used as model systems in our experimental studies, which included reactivity evolution experiments and pore structure characterization using a variety of methods. The key idea behind this project was to appropriately exploit the differences of the sulfidation and sulfation reactions (for instance, different molar volumes of solid products) to elucidate the dependence of the sorptive capacity of a porous sorbent on its physical microstructure. In order to be able to proceed faster and more productively on the analysis of the above defined problem, it was decided to employ in our studies solids whose reaction with SO{sub 2} (limestone calcines) or H{sub 2}S (sorbents based on zinc oxide) had been investigated in detail in past studies by our research group. Reactivity vs time or conversion vs time studies were conducted using thermogravimetry and fixed-bed and fluidized-bed reactors. The pore structure of partially reacted samples collected at selected time instants or conversion levels was analyzed by gas adsorption and mercury porosimetry. For better characterization of the pore structure of the solid samples, we also carried out intraparticle diffusivity measurements by the peak-broadening (chromatographic) method, using a system developed for this purpose in our laboratory. In the context of this part of the project, we also conducted a detailed theoretical investigation of the measurement of effective diffusivities in porous solids using the diffusion-cell method.

Sotirchos, S.V.

1994-03-01T23:59:59.000Z

166

Low and intermediate temperature oxidation of ethanol and ethanol-PRF blends: An experimental and modeling study  

SciTech Connect (OSTI)

In this brief communication, we present new experimental species profile measurements for the low and intermediate temperature oxidation of ethanol under knock-prone conditions. These experiments show that ethanol exhibits no global low temperature reactivity at these conditions, although we note the heterogeneous decomposition of ethanol to ethylene and water. Similar behavior is reported for an E85 blend in n-heptane. Kinetic modeling results are presented to complement these experiments and elucidate the interaction of ethanol and primary reference fuels undergoing cooxidation. (author)

Haas, Francis M.; Chaos, Marcos; Dryer, Frederick L. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

2009-12-15T23:59:59.000Z

167

Nonlinear response of the surface electrostatic potential formed at metal oxide/electrolyte interfaces. A Monte Carlo simulation study  

SciTech Connect (OSTI)

An analysis of surface potential nonlinearity at metal oxide/electrolyte interfaces is presented. By using Grand Canonical Monte Carlo simulations of a simple lattice model of an interface, we show a correlation exists between ionic strength as well as surface site densities and the non-Nernstian response of a metal oxide electrode. We propose two approaches to deal with the 0-nonlinearity: one based on perturbative expansion of the Gibbs free energy and another based on assumption of the pH-dependence of surface potential slope. The theoretical anal ysis based on our new potential form gives excellent performance at extreme pH regions, where classical formulae based on the Poisson-Boltzmann equation fail. The new formula is general and independent of any underlying assumptions. For this reason, it can be directly applied to experimental surface potential measurements, including those for individual surfaces of single crystals, as we present for data reported by Kallay and Preocanin [Kallay, Preocanin J. Colloid and Interface20 Sci. 318 (2008) 290].

Zarzycki, Piotr P.; Rosso, Kevin M.

2010-01-01T23:59:59.000Z

168

Graphene oxide-based materials : synthesis, characterization and applications.  

E-Print Network [OSTI]

??In this study, the properties and applications of graphene oxide-based materials have been explored. Specifically, graphene oxide, i.e. a single layer of graphite oxide, reduced… (more)

Zhou, Xiaozhu.

2010-01-01T23:59:59.000Z

169

Ni coarsening in the three-phase solid oxide fuel cell anode - a phase-field simulation study  

E-Print Network [OSTI]

Ni coarsening in Ni-yttria stabilized zirconia (YSZ) solid oxide fuel cell anodes is considered a major reason for anode degradation. We present a predictive, quantative modeling framework based on the phase-field approach to systematically examine coarsening kinetics in such anodes. The initial structures for simulations are experimentally acquired functional layers of anodes. Sample size effects and error analysis of contact angles are examined. Three phase boundary (TPB) lengths and Ni surface areas are quantatively identified on the basis of the active, dead-end, and isolated phase clusters throughout coarsening. Tortuosity evolution of the pores is also investigated. We find that phase clusters with larger characteristic length evolve slower than those with smaller length scales. As a result, coarsening has small positive effects on transport, and impacts less on the active Ni surface area than the total counter part. TPBs, however, are found to be sensitive to local morphological features and are only i...

Chen, Hsun-Yi; Cronin, J Scott; Wilson, James R; Barnett, Scott A; Thornton, Katsuyo

2012-01-01T23:59:59.000Z

170

X-ray photoelectron spectroscopy study of para-substituted benzoic acids chemisorbed to aluminum oxide thin films  

SciTech Connect (OSTI)

A series of para-substituted, halogenated (F, Cl, Br, and I) benzoic acid monolayers were prepared on the native oxide of aluminum surfaces by solution self-assembly and spin-coating techniques. The monolayers were characterized by x-ray photoelectron spectroscopy (XPS) and water contact angles. Several general trends are apparent. First, the polarity of the solvent is critical to monolayer formation. Protic polar solvents produced low coverage monolayers; in contrast, nonpolar solvents produced higher coverage monolayers. Second, solution deposition yields a higher surface coverage than spin coating. Third, the thickness of the monolayers determined from XPS suggests the plane of the aromatic ring is perpendicular to the surface with the carboxylate functional group most likely binding in a bidentate chelating geometry. Fourth, the saturation coverage (?2.7 × 10{sup 14} molecules cm{sup ?2}) is independent of the para-substituent.

Kreil, Justin; Ellingsworth, Edward; Szulczewski, Greg [Department of Chemistry, The University of Alabama, Shelby Hall, 250 Hackberry Lane, Tuscaloosa, Alabama 35487 (United States)] [Department of Chemistry, The University of Alabama, Shelby Hall, 250 Hackberry Lane, Tuscaloosa, Alabama 35487 (United States)

2013-11-15T23:59:59.000Z

171

Sponge-like Si-SiO{sub 2} nanocomposite—Morphology studies of spinodally decomposed silicon-rich oxide  

SciTech Connect (OSTI)

Sponge-like Si nanostructures embedded in SiO{sub 2} were fabricated by spinodal decomposition of sputter-deposited silicon-rich oxide with a stoichiometry close to that of silicon monoxide. After thermal treatment a mean feature size of about 3 nm was found in the phase-separated structure. The structure of the Si-SiO{sub 2} nanocomposite was investigated by energy-filtered transmission electron microscopy (EFTEM), EFTEM tomography, and atom probe tomography, which revealed a percolated Si morphology. It was shown that the percolation of the Si network in 3D can also be proven on the basis of 2D EFTEM images by comparison with 3D kinetic Monte Carlo simulations.

Friedrich, D.; Schmidt, B.; Heinig, K. H.; Liedke, B.; Mücklich, A.; Hübner, R. [Helmholtz-Zentrum Dresden – Rossendorf, Bautzner Landstr. 400, 01328 Dresden (Germany)] [Helmholtz-Zentrum Dresden – Rossendorf, Bautzner Landstr. 400, 01328 Dresden (Germany); Wolf, D. [Triebenberg Laboratory, Institute of Structure Physics, Technische Universität Dresden, 01062 Dresden (Germany)] [Triebenberg Laboratory, Institute of Structure Physics, Technische Universität Dresden, 01062 Dresden (Germany); Kölling, S. [Fraunhofer Center Nanoelectronic Technologies, Königsbrücker Str. 180, 01099 Dresden (Germany)] [Fraunhofer Center Nanoelectronic Technologies, Königsbrücker Str. 180, 01099 Dresden (Germany); Mikolajick, T. [NaMLab GmbH, Nöthnitzer Str. 64, 01187 Dresden (Germany) [NaMLab GmbH, Nöthnitzer Str. 64, 01187 Dresden (Germany); Technische Universität Dresden, Nöthnitzer Str. 64, 01187 Dresden (Germany)

2013-09-23T23:59:59.000Z

172

Studies on the potential protective effect of cinnamon against bisphenol A- and octylphenol-induced oxidative stress in male albino rats  

Science Journals Connector (OSTI)

Abstract Among the numerous chemicals discharged into the surrounding environment, bisphenol A (BPA) and octylphenol (OP) have been shown to increase oxidative stress in body by disturbing the prooxidant/antioxidant balance of cells. Cinnamon aqueous extract (CAE) is a natural product rich in polyphenolic compounds that have antioxidant activity. This study was designed to investigate the protective efficacy of CAE against oxidative disorders induced by BPA and OP in male albino rats. Animals were divided into 6 groups (10 rats each) and treated orally, 3 times weekly for 50 days. Group 1: control vehicle (olive oil); group 2 (25 mg BPA/kg b.wt./day); group 3 (25 mg OP/kg b.wt./day); group 4 (200 mg CAE/kg b.wt./day); group 5 (CAE 2 h before BPA administration); and group 6 (CAE 2 h before OP administration). BPA- and OP-exposed groups showed insignificant elevation in the final body weight; weight gains and significant reduction only in the relative kidneys weight. Also, BPA and OP exposure resulted in significant increase in serum urea, creatinine and kidney, brain, testicular malondialdehyde (MDA) levels. Significant reduction in tissues reduced glutathione (GSH) contents; catalase (CAT) and superoxide dismutase (SOD) activities were also recorded in BPA and OP exposed animals compared to the control vehicle group. Pretreatment with CAE 2 h either before BPA or OP administration ameliorated the BPA- and OP-induced body weight; weight gains and relative organs weight changes and biochemical adverse effects. CAE pretreatment also protected against the recorded pathological changes in kidney, brain and testis. In conclusion, CAE could ameliorate the oxidative toxic effects of BPA and OP indicating its protective antioxidant effect.

Ashraf M. Morgan; Salah S. El-Ballal; Badre E. El-Bialy; Nermeen B. EL-Borai

2014-01-01T23:59:59.000Z

173

Journal of Power Sources 153 (2006) 6875 Numerical study of a flat-tube high power density solid oxide fuel cell  

E-Print Network [OSTI]

power density (HPD) solid oxide fuel cell (SOFC) is a geometry based on a tubular type SOFC: Flat-tube; High power density (HPD); Solid oxide fuel cell (SOFC); Simulation; Performance; Optimization 1. Introduction A solid oxide fuel cell (SOFC), like any other fuel cell, produces electrical

174

Journal of Power Sources 140 (2005) 331339 Numerical study of a flat-tube high power density solid oxide fuel cell  

E-Print Network [OSTI]

) solid oxide fuel cell (SOFC) is a new design developed by Siemens Westinghouse, based on their formerly.V. All rights reserved. Keywords: Flat-tube; High power density; Solid oxide fuel cell; Simulation; Heat oxide fuel cell Part I. Heat/mass transfer and fluid flow Yixin Lu1, Laura Schaefer, Peiwen Li2

175

Experimental and Theoretical Studies on the Reaction of H2 with NiO: Role of O Vacancies and Mechanism for Oxide  

E-Print Network [OSTI]

, metal oxides are also used as supports of many other catalytic materials (metals, sulfides, carbides are poorly understood in most situations.7 Among the transition-metal oxides, the reduction of H2. I. Introduction Metal oxides are used as catalysts in a large variety of commercial processes

Frenkel, Anatoly

176

FT-IR product studies of the Cl-initiated oxidation of CH{sub 3}Cl in the presence of NO  

SciTech Connect (OSTI)

The deleterious effect of chlorine chemistry on stratospheric ozone levels is now well documented. The Cl-atom initiated oxidation of CH{sub 3}Cl has been studied at 296 K using two different FTIR/environmental chamber systems. In the presence of NO, the carbon-bearing products observed are HCOCl, HCHO, and CO, with yields in 700 Torr of air of (56 {+-} 10), (32 {+-} 6), and (12 {+-} 5)%, respectively. This product distribution is different from previous studies conducted in the absence of NO, in which a nearly 100% yield of HCOCl was obtained. The different product distribution observed in the presence of NO is attributed to the formation and subsequent decomposition of chemically activated CH{sub 2}ClO radicals, formed in the exothermic reaction of CH{sub 2}ClO{sub 2} with NO.

Bilde, M. [Risoe National Lab., Roskilde (Denmark)] [Risoe National Lab., Roskilde (Denmark); Orlando, J.J.; Tyndall, G.S. [National Center for Atmospheric Research, Boulder, CO (United States). Atmospheric Chemistry Div.] [National Center for Atmospheric Research, Boulder, CO (United States). Atmospheric Chemistry Div.; Wallington, T.J.; Hurley, M.D.; Kaiser, E.W. [Ford Motor Co., Dearborn, MI (United States)] [Ford Motor Co., Dearborn, MI (United States)

1999-05-20T23:59:59.000Z

177

Direct Internal Reformation and Mass Transport in the Solid Oxide Fuel Cell Anode: A Pore-Scale Lattice Boltzmann Study with Detailed Reaction Kinetics  

SciTech Connect (OSTI)

The solid oxide fuel cell (SOFC) allows the conversion of chemical energy that is stored in a given fuel, including light hydrocarbons, to electrical power. Hydrocarbon fuels, such as methane, are logistically favourable and provide high energy densities. However, the use of these fuels often results in a decreased efficiency and life. An improved understanding of the reactive flow in the SOFC anode can help address these issues. In this study, the transport and heterogeneous internal reformation of a methane based fuel is addressed. The effect of the SOFC anode's complex structure on transport and reactions is shown to exhibit a complicated interplay between the local molar concentrations and the anode structure. Strong coupling between the phenomenological microstructures and local reformation reaction rates are recognised in this study, suggesting the extension to actual microstructures may provide new insights into the reformation processes.

Grew, Kyle N.; Joshi, Abhijit S.; Chiu, W. K. S.

2010-01-01T23:59:59.000Z

178

Application of a nonisothermal thermogravimetric method to the kinetic study of the reduction of metallic oxides: Part 2. A theoretical treatment of powder bed reduction and its application to the reduction of tungsten oxide by hydrogen  

SciTech Connect (OSTI)

Theoretical treatment of nonisothermal kinetic studies has been extended in the present work to gas-solid reactions in powder beds. An expression for the activation energies for the reaction has been derived on the basis that the reaction proceeds by the movement of the reaction front, the velocity of the movement being kept constant. The reliability of the method has been tested by applying the same to the reduction of tungsten oxide by hydrogen. The experiments were carried out using thermogravimetric technique under both isothermal and nonisothermal conditions. The reaction front is considered to consist of a thin layer of small particles. The rate of the reduction seems to be controlled by the chemical reaction between the product and the unreacted core existing in each of the small particles. Using the expression derived in the present work, the activation energy of the reaction was calculated from the results of the nonisothermal experiments to be 83.62 kJ/mol. This value is in good agreement with the value of 83.17 kJ/mol evaluated from isothermal experiments.

Bustnes, J.A.; Sichen, D.; Seetharaman, S. (Royal Inst. of Tech., Stockholm (Sweden). Department of Theoretical Metallurgy)

1993-06-01T23:59:59.000Z

179

Studies of solution deposited cerium oxide thin films on textured Ni-alloy substrates for YBCO superconductor  

SciTech Connect (OSTI)

Cerium oxide (CeO{sub 2}) buffer layers play an important role for the development of YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) based superconducting tapes using the rolling assisted biaxially textured substrates (RABiTS) approach. The chemical solution deposition (CSD) approach has been used to grow epitaxial CeO{sub 2} films on textured Ni-3 at.% W alloy substrates with various starting precursors of ceria. Precursors such as cerium acetate, cerium acetylacetonate, cerium 2-ethylhexanoate, cerium nitrate, and cerium trifluoroacetate were prepared in suitable solvents. The optimum growth conditions for these cerium precursors were Ar-4% H{sub 2} gas processing atmosphere, solution concentration levels of 0.2-0.5 M, a dwell time of 15 min, and a process temperature range of 1050-1150 deg. C. X-ray diffraction, AFM, SEM, and optical microscopy were used to characterize the CeO{sub 2} films. Highly textured CeO{sub 2} layers were obtained on Ni-W substrates with both cerium acetate and cerium acetylacetonate as starting precursors. YBCO films with a J {sub c} of 1.5 MA/cm{sup 2} were obtained on cerium acetylacetonate-based CeO{sub 2} films with sputtered YSZ and CeO{sub 2} cap layers.

Stewart, E. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6100 (United States); Bhuiyan, M.S. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6100 (United States); Sathyamurthy, S. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6100 (United States); Paranthaman, M. [Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6100 (United States)]. E-mail: paranthamanm@ornl.gov

2006-06-15T23:59:59.000Z

180

Kinetics of the sulfur oxidation on palladium: A combined in situ x-ray photoelectron spectroscopy and density-functional study  

SciTech Connect (OSTI)

We studied the reaction kinetics of sulfur oxidation on the Pd(100) surface by in situ high resolution x-ray photoelectron spectroscopy and ab initio density functional calculations. Isothermal oxidation experiments were performed between 400 and 500 K for small amounts ({approx}0.02 ML) of preadsorbed sulfur, with oxygen in large excess. The main stable reaction intermediate found on the surface is SO{sub 4}, with SO{sub 2} and SO{sub 3} being only present in minor amounts. Density-functional calculations depict a reaction energy profile, which explains the sequential formation of SO{sub 2}, SO{sub 3}, and eventually SO{sub 4}, also highlighting that the in-plane formation of SO from S and O adatoms is the rate limiting step. From the experiments we determined the activation energy of the rate limiting step to be 85 {+-} 6 kJ mol{sup -1} by Arrhenius analysis, matching the calculated endothermicity of the SO formation.

Gotterbarm, Karin; Hoefert, Oliver; Lorenz, Michael P. A.; Streber, Regine; Papp, Christian [Lehrstuhl fuer Physikalische Chemie II, Universitaet Erlangen-Nuernberg, Egerlandstr. 3, 91058 Erlangen (Germany); Luckas, Nicola; Vines, Francesc [Lehrstuhl fuer Theoretische Chemie, Universitaet Erlangen-Nuernberg, Egerlandstr. 3, 91058 Erlangen (Germany); Steinrueck, Hans-Peter [Lehrstuhl fuer Physikalische Chemie II, Universitaet Erlangen-Nuernberg, Egerlandstr. 3, 91058 Erlangen (Germany); Erlangen Catalysis Resource Center (ECRC), Universitaet Erlangen-Nuernberg, Egerlandstr. 3, 91058 Erlangen (Germany); Interdisciplinary Center for Interface Controlled Processes, Egerlandstr. 3, 91058 Erlangen (Germany); Goerling, Andreas [Lehrstuhl fuer Theoretische Chemie, Universitaet Erlangen-Nuernberg, Egerlandstr. 3, 91058 Erlangen (Germany); Interdisciplinary Center for Interface Controlled Processes, Egerlandstr. 3, 91058 Erlangen (Germany)

2012-03-07T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Thermally Oxidized Silicon  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Anneli Munkholm (Lumileds Lighting) and Sean Brennan (SSRL) Anneli Munkholm (Lumileds Lighting) and Sean Brennan (SSRL) Illustration of the silicon positions near the Si-SiO2 interface for a 4° miscut projected onto the ( ) plane. The silicon atoms in the substrate are blue and those in the oxide are red. The small black spots represent the translated silicon positions in the absence of static disorder. The silicon atoms in the oxide have been randomly assigned a magnitude and direction based on the static disorder value at that position in the lattice. The outline of four silicon unit cells is shown in black, whereas the outline of four expanded lattice cells in the oxide is shown in blue One of the most studied devices of modern technology is the field-effect transistor, which is the basis for most integrated circuits. At its heart

182

Forest and Soil Ecosystem Services SOS 4932/SOS 6932  

E-Print Network [OSTI]

, removal of air pollutants, aesthetic beauty, moderation of weather extremes and mitigation of natural treatment, biological filtering, plant remediation) b. Air quality c. Nutrient Cycling d. Carbon (plant and chemical) b. Wildlife habitat and diversity c. Pollination d. Seed Dispersal e. Control

Ma, Lena

183

CERIUM OXIDE (CeO2) PROMOTED OXYGEN CARRIER DEVELOPMENT AND SCALE MODELING STUDY FOR CHEMICAL LOOPING COMBUSTION.  

E-Print Network [OSTI]

??According to IPCC reports, the greenhouse gas CO2 is responsible for global climate change. Studies show that CO2 concentration reached a level of 400 ppm… (more)

Liu, Fang

2013-01-01T23:59:59.000Z

184

As-Received, Ozone Cleaned and Ar+ Sputtered Surfaces of Hafnium Oxide Grown by Atomic Layer Deposition and Studied by XPS  

SciTech Connect (OSTI)

In this study, X-ray photoelectron spectroscopy (XPS) characterization was performed on 47 nm thick hafnium oxide (HfO{sub 2}) films grown by atomic layer deposition using TEMA-Hf/H{sub 2}O at 250 C substrate temperature. HfO{sub 2} is currently being studied as a possible replacement for Silicon Oxide (SiO{sub 2}) as a gate dielectric in electronics transistors. XPS spectra were collected on a Physical Electronics Quantum 2000 Scanning ESCA Microprobe using a monochromatic Al K{sub a} X-ray (1486.7 eV) excitation source. The sample was analyzed under the following conditions: as received, after UV irradiation for five minutes, and after sputter cleaning with 2 kV Ar{sup +} ions for 180 seconds. Survey scans showed carbon, oxygen, and hafnium as the major species in the film, while the only minor species of argon and carbide was detected after sputtering. Adventitious carbon initially composed approximately 18.6 AT% of the surface, but after UV cleaning it was reduced to 2.4 AT%. This demonstrated that that the majority of carbon was due to adventitious carbon. However, after 2 kV Ar{sup +} sputtering there was still only trace amounts of carbon at {approx}1 AT%, Some of this trace carbon is now in the form of a carbide due to the interaction with Ar{sup +} used for sputter cleaning. Furthermore, the stoiciometric ratio of oxygen and hafnium is consistent with a high quality HfO{sub 2} film.

Engelhard, Mark H.; Herman, Jacob A.; Wallace, Robert; Baer, Donald R.

2012-06-27T23:59:59.000Z

185

The Oxidation of Ferritic Stainless Steels in Simulated Solid-Oxide Fuel-Cell Atmospheres  

Science Journals Connector (OSTI)

The cyclic oxidation of a variety of chromia-forming ferritic stainless steels has been studied in the temperature range 700–900°C in atmospheres relevant to solid-oxide fuel-cell operation. The most detriment...

J. E. Hammer; S. J. Laney; R. W. Jackson; K. Coyne; F. S. Pettit…

2007-02-01T23:59:59.000Z

186

Thermoeconomic Modeling and Parametric Study of Hybrid Solid Oxide Fuel Cell â Gas Turbine â Steam Turbine Power Plants Ranging from 1.5 MWe to 10 MWe.  

E-Print Network [OSTI]

??Detailed thermodynamic, kinetic, geometric, and cost models are developed, implemented, and validated for the synthesis/design and operational analysis of hybrid solid oxide fuel cell (SOFC)… (more)

Arsalis, Alexandros

2007-01-01T23:59:59.000Z

187

Time-Resolved XAFS Spectroscopic Studies of B-H and N-H Oxidative Addition to Transition Metal Catalysts Relevant to Hydrogen Storage  

SciTech Connect (OSTI)

Successful catalytic dehydrogenation of aminoborane, H3NBH3, prompted questions as to the potential role of N-H oxidative addition in the mechanisms of these processes. N-H oxidative addition reactions are rare, and in all cases appear to involve initial dative bonding to the metal by the amine lone pairs followed by transfer of a proton to the basic metal. Aminoborane and its trimethylborane derivative block this mechanism and, in principle, should permit authentic N-H oxidative attrition to occur. Extensive experimental work failed to confirm this hypothesis. In all cases either B-H complexation or oxidative addition of solvent C-H bonds dominate the chemistry.

Bitterwolf, Thomas E. [University of Idaho

2014-12-09T23:59:59.000Z

188

Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical study  

SciTech Connect (OSTI)

High voltage cathode materials Li-excess layered oxide compounds Li[Ni{sub x}Li{sub 1/3-2x/3}Mn{sub 2/3-x/3}]O{sub 2} (0 < x < 1/2) are investigated in a joint study combining both computational and experimental methods. The bulk and surface structures of pristine and cycled samples of Li[Ni{sub 1/5}Li{sub 1/5}Mn{sub 3/5}]O{sub 2} are characterized by synchrotron X-Ray diffraction together with aberration corrected Scanning Transmission Electron Microscopy (a-S/TEM). Electron Energy Loss Spectroscopy (EELS) is carried out to investigate the surface changes of the samples before/after electrochemical cycling. Combining first principles computational investigation with our experimental observations, a detailed lithium de-intercalation mechanism is proposed for this family of Li-excess layered oxides. The most striking characteristics in these high voltage high energy density cathode materials are (1) formation of tetrahedral lithium ions at voltage less than 4.45 V and (2) the transition metal (TM) ions migration leading to phase transformation on the surface of the materials. We show clear evidence of a new spinel-like solid phase formed on the surface of the electrode materials after high-voltage cycling. It is proposed that such surface phase transformation is one of the factors contributing to the first cycle irreversible capacity and the main reason for the intrinsic poor rate capability of these materials.

Xu, Bo; Fell, Christopher R.; Chi, Miaofang; Meng, Ying Shirley (ORNL); (Florida); (UCSD)

2011-09-06T23:59:59.000Z

189

Studies on the Surface Oxygen Species and the Catalytic Activity for CO Oxidation of La1-xSrxCo1-xMnxO3, a Perovskite-Type Oxides Catalyst  

Science Journals Connector (OSTI)

The surface oxygen distribution the active oxygen species for CO on the perovskite-type catalyst La1-xSrxCo1-xMnxO3...and its catalytic oxidation activity with CO as probe were investigated by means of XRD, TPD a...

Rong Li; Jiantai Ma; Jingli Xu; Xia Zhou…

2000-07-01T23:59:59.000Z

190

FIRE AND MATERIALS VOL 15,37-42 (1991) A Study of the Synergistic Action of Antimony Oxide in  

E-Print Network [OSTI]

-retardant Polyethylene Y. P. Yang, D. G. Brewer and J. E. S. Venart Department of Chemistry and Fire Science Center oxygen index (LOI) techniques. It was determined that the normal practice of mixing Sb,O, with HBCD between Sb203and the HC1evolved from the PVC. Pitts5 studied the thermal decomposition of Sb

Short, Daniel

191

Study of cobalt-doped lithiumnickel oxides as cathodes for MCFC Prabhu Ganesan, Hector Colon, Bala Haran, Ralph White, Branko N. Popov*  

E-Print Network [OSTI]

challenge remains in the proper selection of materials for the cathode and the current collector. In situ lithiated nickel oxide is in common use as a cathode material in the state-of-the-art MCFC [3]. Nickel oxide also results in loss of active material and a decrease of the active surface area available

Popov, Branko N.

192

Step-Orientation-Dependent Oxidation: From 1D to 2D Oxides  

Science Journals Connector (OSTI)

Using scanning tunneling microscopy and density functional theory, we have studied the initial oxidation of Rh(111) surfaces with two types of straight steps, having {100} and {111} microfacets. The one-dimensional (1D) oxide initially formed at the steps acts as a barrier impeding formation of the 2D oxide on the (111) terrace behind it. We demonstrate that the details of the structure of the 1D oxide govern the rate of 2D oxidation and discuss implications for oxidation of nanoparticles.

J. Klikovits; M. Schmid; L. R. Merte; P. Varga; R. Westerström; A. Resta; J. N. Andersen; J. Gustafson; A. Mikkelsen; E. Lundgren; F. Mittendorfer; G. Kresse

2008-12-29T23:59:59.000Z

193

Transuranic decontamination of nitric acid solutions by the TRUEX solvent extraction process: preliminary development studies. [Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide  

SciTech Connect (OSTI)

This report summarizes the work that has been performed to date at Argonne National Laboratory on the development of the TRUEX process, a solvent extraction process employing a bifunctional organophosphorous reagent in a PUREX process solvent (tributyl phosphate-normal paraffinic hydrocarbons). The purpose of this extraction process is to separate and concentrate transuranic (TRU) elements from nuclear waste. Assessments were made of the use of two TRUEX solvents: one incorporating the well-studied dihexyl-N,N-diethylcarbamoylmethylphosphonate (DHDECMP) and a second incorporating an extractant with superior properties for a 1M HNO/sub 3/ acid feed, octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (O/sub phi/D(IB)CMPO). In this report, conceptual flowsheets for the removal of soluble TRUs from high-level nuclear wastes using these two TRUEX proces solvents are presented, and flowsheet features are discussed in detail. The conceptual flowsheet for TRU-element removal from a PUREX waste by the O/sub phi/D(IB)CMPO-TRUEX process solvent was tested in a bench-scale countercurrent experiment, and results of that experiment are presented and discussed. The conclusion of this study is that the TRUEX process is able to separate TRUs from high-level wastes so that the major portion of the solid waste (approx. 99%) can be classified as non-TRU. Areas where more experimentation is needed are listed at the end of the report. 45 references, 17 figures, 56 tables.

Vandegrift, G.F.; Leonard, R.A.; Steindler, M.J.; Horwitz, E.P.; Basile, L.J.; Diamond, H.; Kalina, D.G.; Kaplan, L.

1984-07-01T23:59:59.000Z

194

Study of degumming process and evaluation of oxidative stability of methyl and ethyl biodiesel of Jatropha curcas L. oil from three different Brazilian states  

Science Journals Connector (OSTI)

Abstract This work describes the production of biodiesel from Jatropha curcas oil. The kernel samples provided by Embrapa-PI, were first crushed in a blender and then subjected to extraction with hexane. The oil yield was between 54.71 ± 0.47 and 64.16 ± 2.88%. The J. curcas oil was then submitted to two different kinds of degumming, first with water and second with H3PO4 to evaluate the influence of these processes in the yield of the transesterification reaction. Methyl and ethyl biodiesel prepared from the degummed oil with H3PO4 had higher conversions than those prepared with the degummed with water. Therefore, among the processes of degumming studied, H3PO4 was more suitable for the treatment of J. curcas oil. The study shows the results about oxidation stability were good, because the biodiesels methyl and ethyl biodiesel have induction period at 13.51 h and 13.03 h without antioxidant addition when submitted a Rancimat text. Such biodiesels had their physicochemical parameters defined under the specifications of ANP Resolutions n° 14/2012 (ANP- National Agency of Petroleum, Natural Gas and Biofuels from Brazil). The results showed that J. curcas cultivation in Brazil is an adequate source for biodiesel production, considering the technical standards available.

Francisca Diana da Silva Araújo; Iranildo C. Araújo; Isabella Cristhina G. Costa; Carla Verônica Rodarte de Moura; Mariana H. Chaves; Eugênio Celso E. Araújo

2014-01-01T23:59:59.000Z

195

Asphalt Oxidation Kinetics and Pavement Oxidation Modeling  

E-Print Network [OSTI]

Most paved roads in the United States are surfaced with asphalt. These asphalt pavements suffer from fatigue cracking and thermal cracking, aggravated by the oxidation and hardening of asphalt. This negative impact of asphalt oxidation on pavement...

Jin, Xin

2012-07-16T23:59:59.000Z

196

High-temperature X-ray diffraction study of crystallization and phase segregation on spinel-type lithium manganese oxides  

SciTech Connect (OSTI)

To study crystallization process of spinel-type Li{sub 1+x}Mn{sub 2-x}O{sub 4}, in-situ high-temperature X-ray diffraction technique (HT-XRD) was utilized for the mixture consisting of Li{sub 2}CO{sub 3} and Mn{sub 2}O{sub 3} as starting material in the temperature range of 25-700 deg. C. In-situ HT-XRD analysis directly revealed that crystallization process of Li{sub 1+x}Mn{sub 2-x}O{sub 4} was significantly affected by the difference in the Li/Mn molar ratio in the precursor. Single phase of stoichiometric LiMn{sub 2}O{sub 4} formed at 700 deg. C. The formation of single phase of spinel was achieved at the lower temperature than the stoichiometric sample as Li/Mn molar ratio in the precursor increased. Lattice parameter of the stoichiometric LiMn{sub 2}O{sub 4} at 25 deg. C was 8.24 A and expanded to 8.31 A at 700 deg. C, which corresponds to the approximately 3% expansion in the unit cell volume. From the slope of the lattice parameter change as a function of temperatures, linear thermal expansion coefficient of the stoichiometric LiMn{sub 2}O{sub 4} was calculated to be 1.2x10{sup -5} deg. C{sup -1} in this temperature range. When the Li/Mn molar ratio in Li{sub 1+x}Mn{sub 2-x}O{sub 4} increased (x > 0.1), the spinel phase segregated into the Li{sub 1+y}Mn{sub 2-y}O{sub 4} (x > y) and Li{sub 2}MnO{sub 3} during heating, which involved the oxygen loss from the materials. During the cooling process from 700 deg. C, and the segregated phase merged into Li{sub 1+x}Mn{sub 2-x}O{sub 4} with oxygen incorporation. Such trend directly observed by in-situ HT-XRD was supported by thermal gravimetric analysis as reversible weight (oxygen) loss/gain at higher temperature (500-700 deg. C). - Graphical abstract: Non-linear variation of lattice parameters of the Li excess LiMn{sub 2}O{sub 4} spinels was observed during cooling process from 700 to 25 deg. C.

Komaba, Shinichi, E-mail: komaba@rs.kagu.tus.ac.j [Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan); Yabuuchi, Naoaki; Ikemoto, Sachi [Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan)

2010-01-15T23:59:59.000Z

197

A Study on the Deposition of Al2O3 Coatings on Polymer Substrates by a Plasma Spray/Micro-Arc Oxidation Two-Step Method  

Science Journals Connector (OSTI)

To increase the wear resistance of polymer matrix composites, alumina coatings were deposited on polymer substrates by a two-step method combining plasma spraying and micro-arc oxidation. The microstructures and ...

Guanhong Sun; Xiaodong He; Jiuxing Jiang; Yue Sun…

2013-02-01T23:59:59.000Z

198

Fretting Wear Study on Micro-Arc Oxidation TiO2 Coating on TC4 Titanium Alloys in Simulated Body Fluid  

Science Journals Connector (OSTI)

Tribological properties of TiO2 coatings synthesized by micro-arc oxidation (MAO) on the surface of TC4...2 coatings presented good tribological properties with lower friction coefficient in SBF. Less wear volume...

Guanghong Zhou; Hongyan Ding; Yue Zhang; Aihui Liu; Yuebin Lin…

2010-12-01T23:59:59.000Z

199

A study of the physical, chemical and biological properties of TiO2 coatings produced by micro-arc oxidation in a Ca–P-based electrolyte  

Science Journals Connector (OSTI)

In this work, a porous and homogeneous titanium dioxide layer was grown on commercially pure titanium substrate using a micro-arc oxidation (MAO) process and Ca–P-based...2 coatings were characterized by X-ray di...

Amanda dos Santos; Joyce R. Araujo…

2014-07-01T23:59:59.000Z

200

Single crystal flow reactor for studying reactivities on metal oxide model catalysts at atmospheric pressure to bridge the pressure gap to the adsorption properties determined under UHV conditions  

Science Journals Connector (OSTI)

A flow reactor for the investigation of heterogeneous catalytic reactions on single crystalline metal oxide model catalysts has been designed. It is located in a high pressure cell attached to an UHV analysis cha...

C. Kuhrs; M. Swoboda; W. Weiss

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Structure, adhesion, and stability of metal/oxide and oxide/oxide interfaces  

SciTech Connect (OSTI)

Studies of structural, electronic, and chemical properties of metal/oxide and oxide/oxide interfaces were performed on well-defined interfaces that created by depositing ultra-thin potassium and aluminum films and their oxides onto single crystal TiO[sub 2] and NiO surfaces. Work focused on determining the structure, growth mechanisms, and morphologies of metal and oxide films as they are deposited an single crystal oxide surfaces using RHEED and atomic force microscopy probing electronic structure, bonding and chemical interactions at the interfaces using x-ray and uv photoelectron spectroscopies (XPS, UPS) and Auger electron spectroscopy (AES), and understanding factors affecting stability and reactivity of the interface regions including the role of defects and impurities. Results indicate that kinetic effects have an important influence on interface structure and composition, and they also show that defects in the oxide substrate induce new electronic states at the interface which play a major role in cation-anion bonding and interface interactions. The results establish a link between electronic and chemical bonding properties and the interface structure and morphology, which is required to successfully manipulate the interfacial properties of advanced ceramic materials.

Lad, R.J.

1992-11-01T23:59:59.000Z

202

Studies on Oxide Cathode Crystals  

Broader source: Energy.gov [DOE]

2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation

203

pH dependence of the internal quantum efficiency and of the peltier heat for photoanodic water oxidation at flame-oxidized titanium. An in situ photoacoustic and photoelectrochemical study  

SciTech Connect (OSTI)

The photocurrent and the photoacoustic signal have been measured simultaneously as a function of electrode potential at an n-type TiO{sub 2} (rutile) thin-film electrode (flame-oxidized Ti) in aqueous Na{sub 2}SO{sub 4} solution at different pH values (0.3-13.7). The internal quantum efficiency of the photocurrent as referred to the number of photons absorbed by the electrode and the Peltier heat for photoanodic oxidation of water have been determined as a function of pH from photoacoustic measurements at 360 nm. The internal quantum efficiency at a band bending of 0.8 V increases with pH in alkaline solution, in accord with a similar finding reported previously by Salvador for the photocurrent efficiency at a rutile sintered electrode. For the Peltier heat two ranges of linear dependence on pH (-58 meV/pH) have been found which have been assigned to the net reactions 2H{sub 2}O + 4h{sup +} {yields} O{sub 2} + 4H{sup +} and 4OH{sup {minus}} + 4h{sup +} {yields} O{sub 2} + 2H{sub 2}O.

Rappich, J.; Dohrmann, J.K. (Freie Universitaet Berlin (West Germany))

1989-06-29T23:59:59.000Z

204

E-Print Network 3.0 - amperometric nitric oxide Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

behavioral... Ref. Neurotransmitters and related compounds Nitric oxide (nitrite) Carbon fiber End-channelInt 8... been studied by microchip CEEC is nitric oxide (NO). NO...

205

Functionalization of Graphene and Graphene Oxide for Biosensing and Imaging  

SciTech Connect (OSTI)

Recent advances in our group about graphene biofunctionalization are discussed. In particular, the functionalization of graphene and graphene oxide, biosensing and bioimaging by using graphene-based nanomaterials, and some fundamental studies of graphene and graphene oxide have been summarized.

Li, Zhaohui; Wang, Ying; Du, Dan; Tang, Zhiwen; Wang, Jun; Lin, Yuehe

2011-08-15T23:59:59.000Z

206

Sulfated Mesoporous Niobium Oxide Catalyzed 5-Hydroxymethylfurfural Formation from Sugars  

Science Journals Connector (OSTI)

Sulfated Mesoporous Niobium Oxide Catalyzed 5-Hydroxymethylfurfural Formation from Sugars ... The effectiveness of sulfated mesoporous niobium oxide (MNO-S) as a catalyst for the production of 5-hydroxymethylfurfural (5-HMF) from sugar was studied and is reported herein. ...

Ernest Lau Sze Ngee; Yongjun Gao; Xi Chen; Timothy Misso Lee; Zhigang Hu; Dan Zhao; Ning Yan

2014-08-25T23:59:59.000Z

207

Study of Substituent Effects on the Photoconductivity of Soluble 2,(3)- and 1,(4)-Substituted Phthalocyaninato- and Naphthalocyaninatotitanium(IV) Oxides  

Science Journals Connector (OSTI)

Soluble alkyl (II, 8a,b), fluoroalkyl (4a), and fluoroalkoxy (4b,c, 8c) 1,(4)- or 2,(3)-substituted phthalocyaninato- and linear 2,(3)- and angular 1,(2)-annulated naphthalocyaninatotitanium(IV) oxides 10, 12, and 14 were synthesized and characterized ...

Götz Winter; Heino Heckmann; Peter Haisch; Wolfgang Eberhardt; Michael Hanack; Larry Lüer; Hans-Joachim Egelhaaf; Dieter Oelkrug

1998-10-28T23:59:59.000Z

208

Ab initio study of lithium intercalation in metal oxides and metal dichalcogenides M. K. Aydinol, A. F. Kohan, and G. Ceder  

E-Print Network [OSTI]

-metal-oxides due to their application potential as rechargeable battery electrodes1 and electrochromic displays.2. In electrochromic applications, band filling is used to adjust the electronic and optical properties.3 Figure 1-potential difference between cathode and anode is desirable as this leads to a high OCV. For electrochromic

Ceder, Gerbrand

209

Propane ammoxidation over Mo–V–Te–Nb–O M1 phase: Density functional theory study of propane oxidative dehydrogenation steps  

Science Journals Connector (OSTI)

Abstract Propane ammoxidation to acrylonitrile catalyzed by the bulk Mo–V–Te–Nb oxides has received considerable attention because it is more environmentally benign than the current process of propylene ammoxidation and relies on a more abundant feedstock. This process is proposed to consist of a series of elementary steps including propane oxidative dehydrogenation (ODH), ammonia and O2 activation, \\{NHx\\} insertion into C3 surface intermediates, etc. Density functional theory calculations were performed here to investigate the three sequential H abstraction steps that successively convert propane into isopropyl, propene, and ?-allyl on cation sites in the proposed selective and active center present in the ab plane of the Mo–V–Te–Nb–O M1 phase. The initial H abstraction from propane was found to be the rate-limiting step of this process, consistent with both the proposed reaction mechanism for propane ammoxidation on the Mo–V–Te–Nb oxides and current understanding of V5+ as the active site for alkane activation on V-based oxides. Te=O was found to be significantly more active than V5+=O for the H abstraction from propane, which suggests that the surface and bulk Te species may be different. The role of Mo=O is most likely limited to being an H acceptor from isopropyl to form propene under ammoxidation conditions.

Junjun Yu; Ye Xu; Vadim V. Guliants

2014-01-01T23:59:59.000Z

210

THE IMPACT OF VARIOUS OXIDIZERS ON THE OVERALL PERFORMACE OF A DIRECT FLAME SOLID OXIDE FUEL CELL.  

E-Print Network [OSTI]

??The power output of a direct-flame solid oxide fuel cell (SOFC) was studied using hydrogen (H2) as the fuel for the flame and various oxidizers,… (more)

Donadio, Nicholas

2010-01-01T23:59:59.000Z

211

Graphene Oxide vs. Reduced Graphene Oxide as saturable absorbers for Er-doped passively mode-locked fiber laser  

Science Journals Connector (OSTI)

In this work we demonstrate comprehensive studies on graphene oxide (GO) and reduced graphene oxide (rGO) based saturable absorbers (SA) for mode-locking of Er-doped fiber lasers. The...

Sobon, Grzegorz; Sotor, Jaroslaw; Jagiello, Joanna; Kozinski, Rafal; Zdrojek, Mariusz; Holdynski, Marcin; Paletko, Piotr; Boguslawski, Jakub; Lipinska, Ludwika; Abramski, Krzysztof M

2012-01-01T23:59:59.000Z

212

Evaluating Environmental Influences Oxidation Kinetics by a  

E-Print Network [OSTI]

strategies for remediation of As-contaminated waters. In this study, the influence of goethite (R D O N A L D L . S P A R K S Department of Land, Air and Water Resources, The University of As-Mn systems demonstrate rapid oxidation of AsIII , catalyzed by Mn-oxides, producing less toxic

Sparks, Donald L.

213

Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

A Solid Oxide Fuel Cell (SOFC) is typically composed of two porous electrodes, interposed between an electrolyte made of a particular solid oxide ceramic material. The system originates from the work of Nernst...

Nigel M. Sammes; Roberto Bove; Jakub Pusz

2006-01-01T23:59:59.000Z

214

National Energy Technology Laboratory Publishes Solid Oxide Fuel Cell  

Broader source: Energy.gov (indexed) [DOE]

National Energy Technology Laboratory Publishes Solid Oxide Fuel National Energy Technology Laboratory Publishes Solid Oxide Fuel Cell Studies National Energy Technology Laboratory Publishes Solid Oxide Fuel Cell Studies July 23, 2013 - 1:07pm Addthis National Energy Technology Laboratory Publishes Solid Oxide Fuel Cell Studies What does this project do? For more information on DOE's efforts to make solid oxide fuel cells an efficient and economically compelling option, please visit: The NETL Solid Oxide Fuel Cells Program Webpage Solid oxide fuel cells are among the cleanest, most efficient power-generating technologies now being developed. They provide excellent electrical efficiencies and are capable of operating on a wide variety of fuels, from coal and natural gas to landfill waste and hydrogen. And with continued advancements, solid oxide fuel cells can provide clean

215

Investigation of the Local Structure of Graphene Oxide  

SciTech Connect (OSTI)

A study of the local structure of graphene oxide is presented. Graphene oxide is understood to be partially oxidized graphene. Absorption peaks corresponding to interlayer states suggest the presence of pristine graphitic nanoislands in graphene oxide. Site-projected partial density of states of carbon atoms bonded to oxygen atoms suggests that the broadening of the peak due to interlayer states in the carbon K-edge spectrum of graphene oxide is predominantly due to formation of epoxide linkages. Density functional theory suggests that multilayers of graphene oxide are linked by peroxide-like linkages.

S Saxena; T Tyson; E Negusse

2011-12-31T23:59:59.000Z

216

Solid oxide electrochemical reactor science.  

SciTech Connect (OSTI)

Solid-oxide electrochemical cells are an exciting new technology. Development of solid-oxide cells (SOCs) has advanced considerable in recent years and continues to progress rapidly. This thesis studies several aspects of SOCs and contributes useful information to their continued development. This LDRD involved a collaboration between Sandia and the Colorado School of Mines (CSM) ins solid-oxide electrochemical reactors targeted at solid oxide electrolyzer cells (SOEC), which are the reverse of solid-oxide fuel cells (SOFC). SOECs complement Sandia's efforts in thermochemical production of alternative fuels. An SOEC technology would co-electrolyze carbon dioxide (CO{sub 2}) with steam at temperatures around 800 C to form synthesis gas (H{sub 2} and CO), which forms the building blocks for a petrochemical substitutes that can be used to power vehicles or in distributed energy platforms. The effort described here concentrates on research concerning catalytic chemistry, charge-transfer chemistry, and optimal cell-architecture. technical scope included computational modeling, materials development, and experimental evaluation. The project engaged the Colorado Fuel Cell Center at CSM through the support of a graduate student (Connor Moyer) at CSM and his advisors (Profs. Robert Kee and Neal Sullivan) in collaboration with Sandia.

Sullivan, Neal P. (Colorado School of Mines, Golden, CO); Stechel, Ellen Beth; Moyer, Connor J. (Colorado School of Mines, Golden, CO); Ambrosini, Andrea; Key, Robert J. (Colorado School of Mines, Golden, CO)

2010-09-01T23:59:59.000Z

217

A Car–Parrinello and path integral molecular dynamics study of the intramolecular lithium bond in the lithium 2-pyridyl- N -oxide acetate  

Science Journals Connector (OSTI)

Lithium bonding in lithium 2-pyridyl- N -oxide acetate has been investigated using classic Car–Parrinello molecular dynamics (CPMD) and the path integral approach [path integrals molecular dynamics (PIMD)]. The simulations have been performed in 300 K. Structures energies and lithium trajectories have been determined. The CPMD results show that the lithium atom is generally equidistant between heavy atoms in the ( O ? Li ? O ) bridge. Applying quantum effects through the PIMD leads to similar conclusion. The theoretical lithium 2-pyridyl- N -oxide acetate infrared spectrum has also been determined using the CPMD calculations. This shows very good agreement with available experimental results and reproduces well the broad low-frequency band observed experimentally. In order to gain deeper understanding of the nature of the lithium bonding topological analysis of the electron localization function has been applied.

Piotr Durlak; Zdzis?aw Latajka; S?awomir Berski

2009-01-01T23:59:59.000Z

218

Graphite Oxidation Thermodynamics/Reactions  

SciTech Connect (OSTI)

The vulnerability of graphite-matrix spent nuclear fuel to oxidation by the ambient atmosphere if the fuel canister is breached was evaluated. Thermochemical and kinetic data over the anticipated range of storage temperatures (200 to 400 C) were used to calculate the times required for a total carbon mass loss of 1 mgcm-2 from a fuel specimen. At 200 C, the time required to produce even this small loss is large, 900,000 yr. However, at 400 C the time required is only 1.9 yr. The rate of oxidation at 200 C is negligible, and the rate even at 400 C is so small as to be of no practical consequence. Therefore, oxidation of the spent nuclear fuel upon a loss of canister integrity is not anticipated to be a concern based upon the results of this study.

Propp, W.A.

1998-09-01T23:59:59.000Z

219

Relation between surface adsorption states and emf in a solid electrolyte concentration cell during carbon monoxide oxidation on platinum studied by local current measurement  

SciTech Connect (OSTI)

The importance of measuring adsorption during surface catalysis has been emphasized often. This is true for the oxidation of carbon monoxide on a platinum surface. Surface adsorption states during the reaction under steady states can be learned from electromotive force (emf) measurement with appropriate assumptions. Two mechanisms for emf generation have been proposed, one is that only oxygen activity generates emf, the other is that both oxygen and CO adsorption generates emf.

Okamoto, H.; Kawamura, G.; Kudo, T.

1984-04-01T23:59:59.000Z

220

Elementary steps of the catalytic NO{sub x} reduction with NH{sub 3}: Cluster studies on reaction paths and energetics at vanadium oxide substrate  

SciTech Connect (OSTI)

We consider different reaction scenarios of the selective catalytic reduction (SCR) of NO in the presence of ammonia at perfect as well as reduced vanadium oxide surfaces modeled by V{sub 2}O{sub 5}(010) without and with oxygen vacancies. Geometric and energetic details as well as reaction paths are evaluated using extended cluster models together with density-functional theory. Based on earlier work of adsorption, diffusion, and reaction of the different surface species participating in the SCR we confirm that at Brønsted acid sites (i.e., OH groups) of the perfect oxide surface nitrosamide, NH{sub 2}NO, forms a stable intermediate. Here adsorption of NH{sub 3} results in NH{sub 4} surface species which reacts with gas phase NO to produce the intermediate. Nitrosamide is also found as intermediate of the SCR near Lewis acid sites of the reduced oxide surface (i.e., near oxygen vacancies). However, here the adsorbed NH{sub 3} species is dehydrogenated to surface NH{sub 2} before it reacts with gas phase NO to produce the intermediate. The calculations suggest that reaction barriers for the SCR are overall higher near Brønsted acid sites of the perfect surface compared with Lewis acid sites of the reduced surface, examined for the first time in this work. The theoretical results are consistent with experimental findings and confirm the importance of surface reduction for the SCR process.

Gruber, M.; Hermann, K. [Inorganic Chemistry Department, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany)] [Inorganic Chemistry Department, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany)

2013-12-28T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Synthesis of Co oxide doped carbon aerogel catalyst and catalytic performance in heterogeneous oxidation of phenol in water  

Science Journals Connector (OSTI)

Co oxide doped carbon aerogel (Co/CA) was prepared, characterised by several techniques, and tested for heterogeneous oxidation of phenol in aqueous solution using oxone as an oxidant. For a comparison, homogeneous oxidation of phenol in Co2+/oxone was also investigated. It was found that homogeneous oxidation of phenol using Co2+/oxone was more effective than Co2+/H2O2 and homogeneous oxidation was faster than heterogeneous Co/CA–oxone. Heterogeneous oxidation of phenol in Co/CA–oxone system followed first order kinetics and the activation energy of the heterogeneous system was estimated to be 62.9 kJ/mol. Several factors influencing phenol degradation in the heterogeneous oxidation were studied. Co/CA loading played a more important role in phenol degradation than oxone concentration, and the presence of other organics in solution resulted in a lower phenol oxidation.

Yasnessya Hardjono; Hongqi Sun; Huyong Tian; C.E. Buckley; Shaobin Wang

2011-01-01T23:59:59.000Z

222

Structure, adhesion, and stability of metal/oxide and oxide/oxide interfaces  

SciTech Connect (OSTI)

During the past six months, we have begun our studies of the fundamental properties of metal/oxide and oxide/oxide heterogeneous interfaces which are being prepared by epitaxial growth of ultra-thin-films on single crystal TiO{sub 2} and NiO surfaces. A new ultra-high vacuum film growth chamber was assembled and coupled to an existing surface analysis chamber; a sample transfer system, metal deposition sources, and a RHEED systems with microchannel plate detection were constructed and implemented. Atomic Force Microscopy was used to characterize and refine the preparation procedures for the single crystal surfaces. The electronic structure of stoichiometric, oxygen-deficient, and potassium-covered TiO{sub 2} (110) surfaces was investigated. Preliminary results on the Al/TiO{sub 2} (110) system have been obtained. Two graduate students have begun thesis research on the project. 6 figs.

Lad, R.J.

1991-01-01T23:59:59.000Z

223

Comparison of the Catalytic Oxidation Reaction on Graphene Oxide and Reduced Graphene Oxide  

E-Print Network [OSTI]

Comparison of the Catalytic Oxidation Reaction on Graphene Oxide and Reduced Graphene Oxide Laboratory (PAL), Pohang 790-784, Republic of Korea ABSTRACT: The capacities of graphene oxide (GO) and reduced graphene oxide (rGO) films grown on silicon substrate to cause the aniline to azobenzene oxidation

Kim, Sehun

224

Metallic Materials in Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

Fe-Cr alloys with variations in chromium content and additions of different elements were studied for potential application in intermediate temperature Solid Oxide Fuel Cell (SOFC). Recently, a new type of FeC...

V. Shemet; J. Piron-Abellan; W.J. Quadakkers…

2005-01-01T23:59:59.000Z

225

An experimental study of external reactor vessel cooling strategy on the critical heat flux using the graphene oxide nano-fluid  

SciTech Connect (OSTI)

External reactor vessel cooling (ERVC) for in-vessel retention (IVR) of corium as a key severe accident management strategy can be achieved by flooding the reactor cavity during a severe accident. In this accident mitigation strategy, the decay heat removal capability depends on whether the imposed heat flux exceeds critical heat flux (CHF). To provide sufficient cooling for high-power reactors such as APR1400, there have been some R and D efforts to use the reactor vessel with micro-porous coating and nano-fluids boiling-induced coating. The dispersion stability of graphene-oxide nano-fluid in the chemical conditions of flooding water that includes boric acid, lithium hydroxide (LiOH) and tri-sodium phosphate (TSP) was checked in terms of surface charge or zeta potential before the CHF experiments. Results showed that graphene-oxide nano-fluids were very stable under ERVC environment. The critical heat flux (CHF) on the reactor vessel external wall was measured using the small scale two-dimensional slide test section. The radius of the curvature is 0.1 m. The dimension of each part in the facility simulated the APR-1400. The heater was designed to produce the different heat flux. The magnitude of heat flux follows the one of the APR-1400 when the severe accident occurred. All tests were conducted under inlet subcooling 10 K. Graphene-oxide nano-fluids (concentration: 10 -4 V%) enhanced CHF limits up to about 20% at mass flux 50 kg/m{sup 2}s and 100 kg/m{sup 2}s in comparison with the results of the distilled water at same test condition. (authors)

Park, S. D.; Lee, S. W.; Kang, S.; Kim, S. M.; Seo, H.; Bang, I. C. [Ulsan National Inst. of Science and Technology UNIST, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulasn Metropolitan City 689-798 (Korea, Republic of)

2012-07-01T23:59:59.000Z

226

Fundamental kinetics of methane oxidation in supercritical water. Summary report  

SciTech Connect (OSTI)

Fundamental understanding of the oxidation of compounds in supercritical water is essential for the design, development and operation of a supercritical water oxidation unit. Previous work in our group determined the oxidation kinetics of carbon monoxide and ethanol in supercritical water for temperatures ranging from 400 to 540 C. Oxidation studies of methane up to 700 C have recently been completed and are presented in this report. Theoretical studies of fundamental kinetics and mechanistic pathways for the oxidation of methane in supercritical water are discussed. Application of current gas phase elementary reaction models are briefly presented and their limitations discussed.

Webley, P.A.; Tester, J.W. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemical Engineering

1989-05-22T23:59:59.000Z

227

Study of Co/CeO2-?-Al2O3 catalysts for steam and oxidative reforming of ethanol for hydrogen production  

Science Journals Connector (OSTI)

Abstract Cobalt catalysts supported on ?Al2O3, CeO2 and CeO2-?Al2O3 were prepared by the impregnation method and applied to steam and oxidative reforming of ethanol. The catalysts were characterized by temperature-programmed reduction with H2 (TPR-H2), X-ray diffraction (XRD), N2-physisorption and diffuse reflectance spectroscopy in the ultra-violet visible range (DRS-UV–Vis). Steam reforming of ethanol was carried out at 400 °C, 500 °C and 600 °C with an ethanol/water feed in a molar ratio of 1:3. The oxidative reforming of ethanol was carried out at 500 °C with an ethanol/H2O/O2 feed in molar proportion 1:3:0.20. Analysis of the gaseous products showed that the Co/?Al2O3 and Co/CeO2-?Al2O3 catalysts were highly selective for H2 and CO2, and this was attributed to the high specific surface area of these catalysts. The addition of O2 to the feed improved the hydrogen selectivity and reduced the carbon formation on Co/?Al2O3, which suffered fast deactivation in the SRE reaction at low temperature.

Thaisa A. Maia; José M. Assaf; Elisabete M. Assaf

2014-01-01T23:59:59.000Z

228

METAL OXIDE NANOPARTICLES  

SciTech Connect (OSTI)

This chapter covers the fundamental science, synthesis, characterization, physicochemical properties and applications of oxide nanomaterials. Explains fundamental aspects that determine the growth and behavior of these systems, briefly examines synthetic procedures using bottom-up and top-down fabrication technologies, discusses the sophisticated experimental techniques and state of the art theory results used to characterize the physico-chemical properties of oxide solids and describe the current knowledge concerning key oxide materials with important technological applications.

FERNANDEZ-GARCIA,M.; RODGRIGUEZ, J.A.

2007-10-01T23:59:59.000Z

229

A mechanistic study explaining the synergistic viscosity increase obtained from polyethylene oxide (PEO) and {beta}-naphthalene sulfonate (BNS) in shotcrete  

SciTech Connect (OSTI)

In shotcrete, a combination of polyethylene oxide (PEO) and {beta}-naphthalene sulfonate (BNS) is commonly applied to reduce rebound. Here, the mechanism for the synergistic viscosity increase resulting from this admixture combination was investigated via x-ray diffraction (XRD), infrared and nuclear magnetic resonance (NMR) spectroscopy. It was found that the electron-rich aromatic rings present in BNS donate electrons to the alkyl protons of PEO and thus increase the electron density there. This rare interaction is known as CH-{pi} interaction and leads to the formation of a supramolecular structure whereby PEO chains bind weakly to BNS molecules. Through this mechanism a polymer network exhibiting exceptionally high molecular weight and thus viscosity is formed. Among polycondensates, sulfanilic acid-phenol-formaldehyde (SPF) provides even higher synergy with PEO than BNS while melamine (PMS), acetone (AFS) or polycarboxylate (PCE) based superplasticizers do not work at all. Effectiveness of lignosulfonates is dependent on their degree of sulfonation.

Pickelmann, J.; Plank, J., E-mail: sekretariat@bauchemie.ch.tum.de

2012-11-15T23:59:59.000Z

230

Time-Resolved Infrared Spectral Studies of Photochemically Induced Oxidative Addition of Benzene to trans-RhCl(CO)(PMe3)2  

Science Journals Connector (OSTI)

Department of Chemistry, University of California, Santa Barbara, California 93106, and Bioscience/Biotechnology Group (CST-4), Chemical Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 ... The observation of a non-zero intercept for this plot would be consistent with partitioning of intermediate 3 between the second-order trapping by CO to reform 1 and other CO-independent pathways, one being an oxidative-addition pathway to give 2. ... This research was sponsored by a grant (Grant No. DE-FG-03-85ER13317) to P.C.F. from the Division of Chemical Sciences, Office of Basic Energy Sciences, U.S. Department of Energy, and by a Collaborative UC/Los Alamos Research (CULAR) Initiative grant from Los Alamos National Laboratory. ...

Jon S. Bridgewater; Brian Lee; Stefan Bernhard; Jon R. Schoonover; Peter C. Ford

1997-12-23T23:59:59.000Z

231

One dimensional modeling of planar solid oxide fuel cell.  

E-Print Network [OSTI]

??Using modeling and simulation, the present work offers parametric study for Planar Solid Oxide Fuel Cell (PSOFC) as a function of fuel gas composition. The… (more)

Ghosh, Ujjal

2005-01-01T23:59:59.000Z

232

Development of non-premixed porous inserted regenerative thermal oxidizer  

Science Journals Connector (OSTI)

In this study, a porous inserted regenerative thermal oxidizer (PRTO) system was developed for a... x emissions and high radiant efficiency. Zirconium dioxide (ZrO2...) ceramic ...

Jun-chun Zhang; Le-ming Cheng; Cheng-hang Zheng…

2013-09-01T23:59:59.000Z

233

Oxygen Coverage Dependence of NO Oxidation on Pt(111). | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dependence of NO Oxidation on Pt(111). Abstract: The interaction of NO with adsorbed atomic oxygen on Pt(111) was studied with temperature programmed desorption (TPD),...

234

Performance and Safety of Olivines and Layered Oxides | Department...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

More Documents & Publications Studies on Oxide Cathode Crystals Phase Behavior and Solid State Chemistry in Olivines Olivines and Substituted Layered Materials...

235

Strong reduction of V{sup 4+} amount in vanadium oxide/hexadecylamine nanotubes by doping with Co{sup 2+} and Ni{sup 2+} ions: Electron paramagnetic resonance and magnetic studies  

SciTech Connect (OSTI)

In this work we present a complete characterization and magnetic study of vanadium oxide/hexadecylamine nanotubes (VO{sub x}/Hexa NT's) doped with Co{sup 2+} and Ni{sup 2+} ions. The morphology of the NT's has been characterized by transmission electron microscopy, while the metallic elements have been quantified by the instrumental neutron activation analysis technique. The static and dynamic magnetic properties were studied by collecting data of magnetization as a function of magnetic field and temperature and by electron paramagnetic resonance. At difference of the majority reports in the literature, we do not observe magnetic dimers in vanadium oxide nanotubes. Also, we observed that the incorporation of metallic ions (Co{sup 2+}, S = 3/2 and Ni{sup 2+}, S = 1) decreases notably the amount of V{sup 4+} ions in the system, from 14-16% (nondoped case) to 2%-4%, with respect to the total vanadium atoms (fact corroborated by XPS experiments) anyway preserving the tubular nanostructure. The method to decrease the amount of V{sup 4+} in the nanotubes improves considerably their potential technological applications as Li-ion batteries cathodes.

Saleta, M. E.; Troiani, H. E.; Ribeiro Guevara, S.; Ruano, G.; Sanchez, R. D. [Centro Atomico Bariloche, CNEA, (8400) S. C. de Bariloche (Argentina); Malta, M. [Depto. de Cs. Exatas e da Terra, Univ. do Estado da Bahia, Cabula Salvador CP 2555 (Brazil); Torresi, R. M. [Instituto de Quimica, Universidad de Sao Paulo, Sao Paulo CP 26077, 05513-970 (Brazil)

2011-05-01T23:59:59.000Z

236

Stabilized chromium oxide film  

DOE Patents [OSTI]

Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

Garwin, Edward L. (Los Altos, CA); Nyaiesh, Ali R. (Palo Alto, CA)

1988-01-01T23:59:59.000Z

237

Stabilized chromium oxide film  

DOE Patents [OSTI]

Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150A are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

Nyaiesh, A.R.; Garwin, E.L.

1986-08-04T23:59:59.000Z

238

Ethylene Oxide Explosions  

Science Journals Connector (OSTI)

... THE occasional occurrence of ethylene oxide explosions during the fumigation of dried fruit has led us to undertake a detailed ... yielded results somewhat like those for acetaldehyde1,2.. Cool flames can be initiated in ethylene oxide – air mixtures in the neighbourhood of 330° C. at atmospheric pressure. ...

J. H. BURGOYNE; F. A. BURDEN

1948-07-31T23:59:59.000Z

239

Oxidation of boron silicide and materials based on it  

SciTech Connect (OSTI)

Boron silicide and compounds based on its containing titanium, chromium, nickel, and yttrium and scandium oxides are studied for their oxidation in air from room temperature to 1300{degrees}C. It is shown that chromium boride markedly improves the heat resistance of B{sub 4}Si over a wide temperature range (700-1300{degrees}C) probably as a result chromium-oxide dissolution in borosilicate glass and alteration of its structure. A favorable effect of yttrium and scandium oxides as well of nickel silicide appears at above 1000{degrees}C as a result of forming complex oxide compounds in the scale.

Golovko, E.I.; Makarenko, G.N.; Voitovich, R.F.; Fedorus, V.B. [Institute of Materials Science, Kiev (Russian Federation)

1994-05-01T23:59:59.000Z

240

Oxidation kinetics of aluminum diboride  

SciTech Connect (OSTI)

The oxidation characteristics of aluminum diboride (AlB{sub 2}) and a physical mixture of its constituent elements (Al+2B) were studied in dry air and pure oxygen using thermal gravimetric analysis to obtain non-mechanistic kinetic parameters. Heating in air at a constant linear heating rate of 10 °C/min showed a marked difference between Al+2B and AlB{sub 2} in the onset of oxidation and final conversion fraction, with AlB{sub 2} beginning to oxidize at higher temperatures but reaching nearly complete conversion by 1500 °C. Kinetic parameters were obtained in both air and oxygen using a model-free isothermal method at temperatures between 500 and 1000 °C. Activation energies were found to decrease, in general, with increasing conversion for AlB{sub 2} and Al+2B in both air and oxygen. AlB{sub 2} exhibited O{sub 2}-pressure-independent oxidation behavior at low conversions, while the activation energies of Al+2B were higher in O{sub 2} than in air. Differences in the composition and morphology between oxidized Al+2B and AlB{sub 2} suggested that Al{sub 2}O{sub 3}–B{sub 2}O{sub 3} interactions slowed Al+2B oxidation by converting Al{sub 2}O{sub 3} on aluminum particles into a Al{sub 4}B{sub 2}O{sub 9} shell, while the same Al{sub 4}B{sub 2}O{sub 9} developed a needle-like morphology in AlB{sub 2} that reduced oxygen diffusion distances and increased conversion. The model-free kinetic analysis was critical for interpreting the complex, multistep oxidation behavior for which a single mechanism could not be assigned. At low temperatures, moisture increased the oxidation rate of Al+2B and AlB{sub 2}, but both appear to be resistant to oxidation in cool, dry environments. - Graphical abstract: Isothermal kinetic data for AlB{sub 2} in air, showing a constantly decreasing activation energy with increasing conversion. Model-free analysis allowed for the calculation of global kinetic parameters despite many simultaneous mechanisms occurring concurrently. (a) Time–temperature plots, (b) conversion as a function of time, (c) Arrhenius plots used to calculate activation energies, and (d) activation energy as a function of conversion. Display Omitted - Highlights: • First reported kinetic parameters for AlB{sub 2} and Al+2B oxidation in air and O{sub 2}. • Possible mechanism of enhanced boron combustion presented. • Moisture sensitivity shown to be problematic for AlB{sub 2}, less for Al+2B.

Whittaker, Michael L., E-mail: michaelwhittaker2016@u.northwestern.edu [Department of Materials Science and Engineering, University of Utah, 122S. Central Campus Drive, Salt Lake City, UT 84112 (United States); Sohn, H.Y. [Department of Metallurgical Engineering, University of Utah, 135S 1460 E, Rm 00412, Salt Lake City, UT 84112 (United States); Cutler, Raymond A. [Ceramatec, Inc., 2425S. 900W., Salt Lake City, UT 84119 (United States)

2013-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Phase-Transfer-Catalyzed Oxidations  

Science Journals Connector (OSTI)

Phase-transfer catalysis (PTC) offers many excellent opportunities for conducting oxidation reactions using inexpensive primary oxidants such as oxygen, sodium hypochlorite, hydrogen peroxide, electrooxidation...

Charles M. Starks; Charles L. Liotta; Marc E. Halpern

1994-01-01T23:59:59.000Z

242

Regenerative catalytic oxidation  

SciTech Connect (OSTI)

Currently Regenerative Thermal Oxidizers (R.T.O.`s) are an accepted technology for the control of volatile organic compounds (VOC`s) and hazardous air pollutants (HAP`s). This control technology, when introduced, offered substantial reductions in operating costs, especially auxiliary fuel requirements when compared to existing control technologies such as recuperative thermal and recuperative catalytic oxidizers. While these savings still exist, there is a demand for control of new and/or hybrid technologies, one of which is Regenerative Catalytic Oxidizers (R.C.O.`s). This paper will explore the development of regenerative catalytic oxidation from the theoretical stage through pilot testing through a commercial installation. The operating cost of R.C.O.`s will be compared to R.T.O.`s to verify the savings that are achievable through the use of regenerative catalytic oxidation. In the development of this technology, which is a combination of two (2) existing technologies, R.T.O.`s and catalysis, a second hybrid technology was explored and pilot tested. This is a combination R.C.O. for VOC and HAP control and simultaneous SCR (Selective Catalytic Reduction) for NOx (Oxides of Nitrogen) control. Based on the pilot and full scale testing, both regenerative catalytic oxidizers and systems which combine R.C.O. with SCR for both VOC and NOx reduction are economically viable and are in fact commercially available. 6 figs., 2 tabs.

Gribbon, S.T. [Engelhard Process Emission Systems, South Lyon, MI (United States)

1996-12-31T23:59:59.000Z

243

Effect of Micro Arc Oxidation Coatings on Corrosion Resistance of 6061-Al Alloy  

Science Journals Connector (OSTI)

In the present study, the corrosion behavior of micro arc oxidation (MAO) coatings deposited at two current...

Nitin P. Wasekar; A. Jyothirmayi…

2008-10-01T23:59:59.000Z

244

SOLID OXIDE PLANAR AND TUBULAR SOLID OXIDE FUEL  

E-Print Network [OSTI]

SOLID OXIDE PLANAR AND TUBULAR SOLID OXIDE FUEL CELLS Dynamic Simulation Approach Modular Approach · Parallel planes: PSOFC · Other: combustor, reformer Solid Oxide Fuel Cell Electrochemistry Cell Reactions · Slow pressure transients #12;Fuel Cell Assumptions · H2 electrochemically oxidized only · CO consumed

Mease, Kenneth D.

245

NORTHWESTERN UNIVERSITY A Study of Oxides for Solid Oxide Cells  

E-Print Network [OSTI]

owing to issues of cost, durability, and performance. In this thesis, three dierent aspects of solid;4 Then, degradation taking place when the cell is run in electrolysis mode is discussed. A high current allows for a high production rate of hydrogen gas. However, this can also lead to oxygen bubble

Shkel, Andrei M.

246

Syngas Oxidation Mechanism  

Science Journals Connector (OSTI)

A comprehensive analysis of synthesis gas (syngas) oxidation kinetics in wide ranges of temperature ... on the basis of the reaction mechanism of syngas ignition and combustion in air. A vast set of experimental ...

A. M. Starik; N. S. Titova; A. S. Sharipov…

2010-09-01T23:59:59.000Z

247

Mechanisms of Oxide Scale Formation on Ferritic Interconnect Steel in Simulated Low and High pO2 Service Environments of Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

The Laves phase strengthened ferritic steel Crofer 22 H has recently been proposed as construction material for interconnects in solid oxide fuel cells (SOFCs). In the present study, the oxidation kinetics of ...

L. Niewolak; D. J. Young; H. Hattendorf; L. Singheiser…

2014-08-01T23:59:59.000Z

248

Controlled CO preferential oxidation  

DOE Patents [OSTI]

Method is described for controlling the supply of air to a PROX (PReferential OXidation for CO cleanup) reactor for the preferential oxidation in the presence of hydrogen wherein the concentration of the hydrogen entering and exiting the PROX reactor is monitored, the difference there between correlated to the amount of air needed to minimize such difference, and based thereon the air supply to the PROX reactor adjusted to provide such amount and minimize such difference. 2 figs.

Meltser, M.A.; Hoch, M.M.

1997-06-10T23:59:59.000Z

249

Thermal-fluid and electrochemical modeling and performance study of a planar solid oxide electrolysis cell : analysis on SOEC resistances, size, and inlet flow conditions.  

SciTech Connect (OSTI)

Argonne National Laboratory and Idaho National Laboratory researchers are analyzing the electrochemical and thermal-fluid behavior of solid oxide electrolysis cells (SOECs) for high temperature steam electrolysis using computational fluid dynamics (CFD) techniques. The major challenges facing commercialization of steam electrolysis technology are related to efficiency, cost, and durability of the SOECs. The goal of this effort is to guide the design and optimization of performance for high temperature electrolysis (HTE) systems. An SOEC module developed by FLUENT Inc. as part of their general CFD code was used for the SOEC analysis by INL. ANL has developed an independent SOEC model that combines the governing electrochemical mechanisms based on first principals to the heat transfer and fluid dynamics in the operation of SOECs. The ANL model was embedded into the commercial STAR-CD CFD software, and is being used for the analysis of SOECs by ANL. The FY06 analysis performed by ANL and reported here covered the influence of electrochemical properties, SOEC component resistances and their contributing factors, SOEC size and inlet flow conditions, and SOEC flow configurations on the efficiency and expected durability of these systems. Some of the important findings from the ANL analysis are: (1) Increasing the inlet mass flux while going to larger cells can be a compromise to overcome increasing thermal and current density gradients while increasing the cell size. This approach could be beneficial for the economics of the SOECs; (2) The presence of excess hydrogen at the SOEC inlet to avoid Ni degradation can result in a sizeable decrease in the process efficiency; (3) A parallel-flow geometry for SOEC operation (if such a thing be achieved without sealing problems) yields smaller temperature gradients and current density gradients across the cell, which is favorable for the durability of the cells; (4) Contact resistances can significantly influence the total cell resistance and cell temperatures over a large range of operating potentials. Thus it is important to identify and avoid SOEC stack conditions leading to such high resistances due to poor contacts.

Yildiz, B.; Smith, J.; Sofu, T.; Nuclear Engineering Division

2008-06-25T23:59:59.000Z

250

Cu- and Ag-modified cerium oxide catalysts for methane oxidation  

SciTech Connect (OSTI)

The catalytic activity of nanocrystalline doped ceria and Cu- and Ag-modified ceria for the complete oxidation of methane was studied in this work. The catalyst structure was studied by X-ray diffraction (XRD) and related to the availability of low-temperature oxygen species. Selected samples were also analyzed by STEM/EDX, HRTEM, and XPS. Temperature-programmed reduction (TPR) by H{sub 2} and CH{sub 4}, as well as oxygen chemisorption, measurements were used to characterize the different oxygen species present on the catalyst. La and Zr were used as dopants to modify the crystal size and reduction properties of ceria. Enhanced activity for the complete oxidation of methane is discussed in terms of ceria reducibility, crystal size, and formation of oxygen defects at the surface (extrinsic oxygen vacancies). Addition of transition metal oxides (CuO) or transition metals (Ag) improves the low-temperature oxidation activity of cerium oxide. The interaction of ceria with Ag and CuO is a strong function of the crystal size of ceria. In the presence of the transition metal or metal oxide, a small crystal size of ceria favors the formation of highly reducible oxygen species and enhances the methane oxidation activity.

Kundakovic, L.; Flytzani-Stephanopoulis, M. [Tufts Univ., Medford, MA (United States). Dept. of Chemical Engineering] [Tufts Univ., Medford, MA (United States). Dept. of Chemical Engineering

1998-10-01T23:59:59.000Z

251

Modeling of Diesel Oxidation Catalyst  

Science Journals Connector (OSTI)

Modeling of Diesel Oxidation Catalyst ... Optimization of hydrocarbon (HC) oxidation over a diesel oxidation catalyst (DOC) requires consideration of (i) HC gas diffusion into the catalyst layer, (ii) HC gas adsorption and desorption from catalyst sites, and (iii) kinetics of the oxidation reaction. ... Mutagenicity of Diesel Engine Exhaust Is Eliminated in the Gas Phase by an Oxidation Catalyst but Only Slightly Reduced in the Particle Phase ...

Yasushi Tanaka; Takashi Hihara; Makoto Nagata; Naoto Azuma; Akifumi Ueno

2005-09-30T23:59:59.000Z

252

The burnup dependence of light water reactor spent fuel oxidation  

SciTech Connect (OSTI)

Over the temperature range of interest for dry storage or for placement of spent fuel in a permanent repository under the conditions now being considered, UO{sub 2} is thermodynamically unstable with respect to oxidation to higher oxides. The multiple valence states of uranium allow for the accommodation of interstitial oxygen atoms in the fuel matrix. A variety of stoichiometric and nonstoichiometric phases is therefore possible as the fuel oxidizers from UO{sub 2} to higher oxides. The oxidation of UO{sub 2} has been studied extensively for over 40 years. It has been shown that spent fuel and unirradiated UO{sub 2} oxidize via different mechanisms and at different rates. The oxidation of LWR spent fuel from UO{sub 2} to UO{sub 2.4} was studied previously and is reasonably well understood. The study presented here was initiated to determine the mechanism and rate of oxidation from UO{sub 2.4} to higher oxides. During the early stages of this work, a large variability in the oxidation behavior of samples oxidized under nearly identical conditions was found. Based on previous work on the effect of dopants on UO{sub 2} oxidation and this initial variability, it was hypothesized that the substitution of fission product and actinide impurities for uranium atoms in the spent fuel matrix was the cause of the variable oxidation behavior. Since the impurity concentration is roughly proportional to the burnup of a specimen, the oxidation behavior of spent fuel was expected to be a function of both temperature and burnup. This report (1) summarizes the previous oxidation work for both unirradiated UO{sub 2} and spent fuel (Section 2.2) and presents the theoretical basis for the burnup (i.e., impurity concentration) dependence of the rate of oxidation (Sections 2.3, 2.4, and 2.5), (2) describes the experimental approach (Section 3) and results (Section 4) for the current oxidation tests on spent fuel, and (3) establishes a simple model to determine the activation energies associated with spent fuel oxidation (Section 5).

Hanson, B.D.

1998-07-01T23:59:59.000Z

253

Gold catalyst Styrene Benzaldehyde Styrene oxide Acetophenone  

E-Print Network [OSTI]

O O O + + O2 Gold catalyst Styrene Benzaldehyde Styrene oxide Acetophenone studies. However, the study by Turner et al.1 seems to be the first to use Au55 in the synthesis of supported gold catalysts a very narrow and reproducible size distribution for the result- ing particles. Traditional catalyst

Rouyer, Francois

254

A neutron diffraction study of the magnetic structure for the perovskite-type mixed oxides La(Mn, Cr)03 and (La, Sr)Fe03  

E-Print Network [OSTI]

and Type A Magnetic Cell.............................. 55 12. Magnetic Structure Types A and G According to Semicovalent Bonding Scheme ........................................ 59 13. Temperature Difference Pattern and Magnetic Cell for G... techniques have been applied to the study of the magnetic structure properties of perovskite-type compounds La(Cr,Mn)02 and (La^S^FeOy The perovskite cell is ideally cubic with one molecule ABO^ per unit cell. For the compounds studied the B ion located...

Bents, Ulrich H.

2013-10-04T23:59:59.000Z

255

Zinc sorption by iron oxides and soil samples  

E-Print Network [OSTI]

(Head of Department) May 1989 ABSTRACT Zinc Sorption by Iron Oxides and Soil Samples. (May 1989) Markku Juhani Yli-Halla, M. S. University of Helsinki, Finland Chair of Advisory Committee: Dr. Richard H. Loeppert Zn sorption by synthetic Fe oxide... and soil samples was studied. The purpose was to examine the effect of crystallinity and adsorbed silica on Zn adsorption by synthetic Fe oxide using goethite and ferrihydrite as test materials. Zn sorption by acid soil samples from Finland and a...

Yli-Halla, Markku Juhani

1989-01-01T23:59:59.000Z

256

Synthesis of zirconium oxide nanoparticle by sol-gel technique  

SciTech Connect (OSTI)

Zirconium oxide nanoparticle is synthesized using sol-gel technique. Various mole ratio of ammonia solution and nitric acid relative to zirconium propoxide is added in the reaction to study the effect on the crystallinity and particle size on zirconium oxide particle. Zirconium oxide synthesized with nitric acid have the smallest particle size under FESEM image and show the increasing formation of crystalline tetragonal phase under XRD diffractogram.

Lim, H. S.; Ahmad, A.; Hamzah, H. [School of Chemical Science and Food Technology, Faculty of Science and Technology, National University of Malaysia, 43600 Bangi (Malaysia)

2013-11-27T23:59:59.000Z

257

Oxidation kinetics of some nickel-based superalloy foils and electronic resistance of the oxide scale formed in air. Part 1  

SciTech Connect (OSTI)

Haynes 230, Inconel 625, Inconel 718, and Hastelloy X foil specimens were oxidized in air for several thousand hours in the temperature range of 800--1,100 C. The oxidation kinetics of alloys studied obeyed the parabolic rate law. Haynes 230 exhibited the slowest oxidation kinetics of the alloys studied. X-ray diffraction, scanning electron microscopy, and electron probe microanalysis (EPMA) were the principal characterization tools employed. Chromium oxide, Cr{sub 2}O{sub 3}, was the predominant oxide phase in the oxide scale of all alloys studied. Manganese chromate was also detected in the oxide scales of Haynes 230, Hastelloy X, and Inconel 625. EPMA showed that the concentration of Mn in the oxide scale was much higher than in the alloy, indicating selective oxidation of Mn. The electronic resistance of the oxide scale was measured in air at temperatures up to 800 C on samples oxidized in air for up to several thousand hours. The oxide scale on Haynes 230 exhibited the lowest area-specific resistance, consistent with its slower oxidation kinetics.

England, D.M.; Virkar, A.V.

1999-09-01T23:59:59.000Z

258

Oxidative Tritium Decontamination System  

SciTech Connect (OSTI)

The Princeton Plasma Physics Laboratory, Tritium Systems Group has developed and fabricated an Oxidative Tritium Decontamination System (OTDS), which is designed to reduce tritium surface contamination on various components and items. The system is configured to introduce gaseous ozone into a reaction chamber containing tritiated items that require a reduction in tritium surface contamination. Tritium surface contamination (on components and items in the reaction chamber) is removed by chemically reacting elemental tritium to tritium oxide via oxidation, while purging the reaction chamber effluent to a gas holding tank or negative pressure HVAC system. Implementing specific concentrations of ozone along with catalytic parameters, the system is able to significantly reduce surface tritium contamination on an assortment of expendable and non-expendable items. This paper will present the results of various experimentation involving employment of this system.

Charles A. Gentile; John J. Parker; Gregory L. Guttadora; Lloyd P. Ciebiera

2002-02-11T23:59:59.000Z

259

Methanol partial oxidation reformer  

DOE Patents [OSTI]

A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

Ahmed, Shabbir (Bolingbrook, IL); Kumar, Romesh (Naperville, IL); Krumpelt, Michael (Naperville, IL)

1999-01-01T23:59:59.000Z

260

Methanol partial oxidation reformer  

DOE Patents [OSTI]

A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

Ahmed, Shabbir (Bolingbrook, IL); Kumar, Romesh (Naperville, IL); Krumpelt, Michael (Naperville, IL)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Methanol partial oxidation reformer  

DOE Patents [OSTI]

A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

Ahmed, S.; Kumar, R.; Krumpelt, M.

1999-08-17T23:59:59.000Z

262

Methanol partial oxidation reformer  

DOE Patents [OSTI]

A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

Ahmed, S.; Kumar, R.; Krumpelt, M.

1999-08-24T23:59:59.000Z

263

Looking at Transistor Gate Oxide Formation in Real Time  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Looking at Transistor Gate Oxide Formation in Real Time Print Looking at Transistor Gate Oxide Formation in Real Time Print The oxide gate layer is critical to every transistor, and present-day layer thicknesses are in the 10-20 Å range (1-2 nm). However, little information exists on the oxidation process at this thickness. Available results are either for thicker layers grown under high-pressure conditions or for only the first couple of monolayers studied under high-vacuum conditions. Now, for the first time, a group of researchers has obtained real-time oxidation results for this elusive range. Using the ambient-pressure x-ray photoelectron spectroscopy (APXPS) endstation at ALS Beamline 9.3.2, they examined oxidation of Si(100) at pressures up to 1 torr and temperatures up to 450 ºC. The Si 2p chemical shifts allowed determination of oxide thickness as a function of time with a precision of 1-2 Å. The initial oxidation rate was very high (up to ~234 Å/h). Then, after an initial oxide thickness of 6-22 Å was formed, the rate decreased markedly (~1.5-4.0Å/h). Neither rate regime can be explained by the standard Deal-Grove (D-G) model for Si oxidation. These results are a significant step toward developing a better understanding of this critical thickness regime.

264

Looking at Transistor Gate Oxide Formation in Real Time  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Looking at Transistor Gate Oxide Formation in Real Time Print Looking at Transistor Gate Oxide Formation in Real Time Print The oxide gate layer is critical to every transistor, and present-day layer thicknesses are in the 10-20 Å range (1-2 nm). However, little information exists on the oxidation process at this thickness. Available results are either for thicker layers grown under high-pressure conditions or for only the first couple of monolayers studied under high-vacuum conditions. Now, for the first time, a group of researchers has obtained real-time oxidation results for this elusive range. Using the ambient-pressure x-ray photoelectron spectroscopy (APXPS) endstation at ALS Beamline 9.3.2, they examined oxidation of Si(100) at pressures up to 1 torr and temperatures up to 450 ºC. The Si 2p chemical shifts allowed determination of oxide thickness as a function of time with a precision of 1-2 Å. The initial oxidation rate was very high (up to ~234 Å/h). Then, after an initial oxide thickness of 6-22 Å was formed, the rate decreased markedly (~1.5-4.0Å/h). Neither rate regime can be explained by the standard Deal-Grove (D-G) model for Si oxidation. These results are a significant step toward developing a better understanding of this critical thickness regime.

265

Looking at Transistor Gate Oxide Formation in Real Time  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Looking at Transistor Gate Oxide Formation in Real Time Print Looking at Transistor Gate Oxide Formation in Real Time Print The oxide gate layer is critical to every transistor, and present-day layer thicknesses are in the 10-20 Å range (1-2 nm). However, little information exists on the oxidation process at this thickness. Available results are either for thicker layers grown under high-pressure conditions or for only the first couple of monolayers studied under high-vacuum conditions. Now, for the first time, a group of researchers has obtained real-time oxidation results for this elusive range. Using the ambient-pressure x-ray photoelectron spectroscopy (APXPS) endstation at ALS Beamline 9.3.2, they examined oxidation of Si(100) at pressures up to 1 torr and temperatures up to 450 ºC. The Si 2p chemical shifts allowed determination of oxide thickness as a function of time with a precision of 1-2 Å. The initial oxidation rate was very high (up to ~234 Å/h). Then, after an initial oxide thickness of 6-22 Å was formed, the rate decreased markedly (~1.5-4.0Å/h). Neither rate regime can be explained by the standard Deal-Grove (D-G) model for Si oxidation. These results are a significant step toward developing a better understanding of this critical thickness regime.

266

Tetraalklylammonium polyoxoanionic oxidation catalysts  

DOE Patents [OSTI]

Alkanes are catalytically oxidized in air or oxygen using iron-substituted polyoxoanions (POAs) of the formula: H{sub e{minus}z}[(n-C{sub 4}H{sub 9}){sub 4}N]{sub z}(XM{sub 11}M{prime}O{sub 39}){sup {minus}e}. The M{prime} (e.g., iron(III)/iron(II)) reduction potential of the POAs is affected by selection of the central atom X and the framework metal M, and by the number of tetrabutyl-ammonium groups. Decreased Fe(III)/Fe(II) reduction potential has been found to correlate to increased oxidation activity.

Ellis, P.E.; Lyons, J.E.; Myers, H.K. Jr.; Shaikh, S.N.

1998-10-06T23:59:59.000Z

267

Tetraalykylammonium polyoxoanionic oxidation catalysts  

DOE Patents [OSTI]

Alkanes are catalytically oxidized in air or oxygen using iron-substituted polyoxoanions (POAs) of the formula: H.sub.e-z ›(n-C.sub.4 H.sub.9).sub.4 N!.sub.z (XM.sub.11 M'O.sub.39).sup.-e The M' (e.g., iron(III)/iron(II)) reduction potential of the POAs is affected by selection of the central atom X and the framework metal M, and by the number of tetrabutyl-ammonium groups. Decreased Fe(III)/Fe(II) reduction potential has been found to correlate to increased oxidation activity.

Ellis, Paul E. (Downingtown, PA); Lyons, James E. (Wallingford, PA); Myers, Jr., Harry K. (Cochranville, PA); Shaikh, Shahid N. (Media, PA)

1998-01-01T23:59:59.000Z

268

Formation of Nanocrystalline Germanium via Oxidation of Si?.??Ge?.?? for Memory Device Applications  

E-Print Network [OSTI]

In this work, we studied the possibility of synthesizing nanocrystalline germanium (Ge) via dry and wet oxidation of both amorphous and polycrystalline Si?.??Ge?.?? films. In dry oxidation, Ge was rejected from the growing ...

Kan, Eric Win Hong

269

XPS Analysis of Ti6Al4V Oxidation Under UHV Conditions  

Science Journals Connector (OSTI)

An alternative strategy to study the distribution of oxides in the passive layer is to monitor their growth directly on the metal surface. For this, previous oxide layers are removed by sputtering to obtain clean...

M. Hierro-Oliva; A. M. Gallardo-Moreno…

2014-12-01T23:59:59.000Z

270

Nano zinc oxide for UV protection of textiles  

Science Journals Connector (OSTI)

This paper describes the effect on the fading of dyed polyester fabrics in artificial sunlight, when the Ultra Violet (UV) component of the radiation was blocked by coating the fabric with zinc oxide nanoparticles, dispersed in an acrylic polymer. Zinc oxide is photoactive and generates superoxide and hydroxyl radicals (Reactive Oxygen Species; ROS) when irradiated with UV in the presence of oxygen and water. The results for the four dyes studied show that different dye chromophores interact differently with ROS. Selection of dyes with anti oxidant properties or addition of other anti oxidants may reduce the adverse effects of ROS.

Lu Sun; John A. Rippon; Peter G. Cookson; Xungai Wang; Ken King; Olga Koulaeva; Reno Beltrame

2008-01-01T23:59:59.000Z

271

A Porphyrin-Stabilized Iridium Oxide Water Oxidation Catalyst  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A Porphyrin-Stabilized Iridium Oxide Water Oxidation Catalyst Authors: Sherman, B. D., Pillai, S., Kodis, G., Bergkamp, J., Mallouk, T. E., Gust, D., Moore, T. A., and Moore, A. L....

272

Oxidative Reforming of Biodiesel Over Molybdenum (IV) Oxide  

E-Print Network [OSTI]

as potential feedstock in solid oxide fuel cells. Petroleum based fuels become scarcer daily, and biodiesel for use in solid oxide fuel cells. This cutting edge area of research continues to be important as energy prove useful for solid oxide fuel cells. METHODS Commercial molybdenum dioxide was used for all tests

Collins, Gary S.

273

{sup 17}O NMR investigations of oxidative degradation in polymers  

SciTech Connect (OSTI)

We have initiated studies using both solution and solid state magic angle spinning {sup 17}O NMR for a series of oxidatively aged polymers. This short note reports the solution {sup 17}O NMR for oxidatively degraded polypropylene, ethylene-propylene-diene, polyisoprene, and nitrile rubber. Enriched O{sub 2} is used during the accelerated aging. 3 figs, 7 refs.

Alam, T.M.; Celina, M.; Assink, R.A.; Gillen, K.T.; Clough, R.L.

1996-12-31T23:59:59.000Z

274

Low-Temperature Oxidation and Cool Flames of Propane  

Science Journals Connector (OSTI)

...1954 research-article Low-Temperature Oxidation and Cool Flames of Propane J. H. Knox R. G. W. Norrish A detailed analytical study of the cool-flame oxidation of propane has been carried out using a continuous-flow technique with a view...

1954-01-01T23:59:59.000Z

275

Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene  

E-Print Network [OSTI]

Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene Nanoribbons Oded Hod,* Vero´nica Barone theoretical study of the electronic properties and relative stabilities of edge-oxidized zigzag graphene with nanometer scale dimen- sions. Recently, a new type of graphene-based material was experimentally realized.12

Hod, Oded

276

Modeling of UO{sub 2} oxidation in steam atmosphere  

SciTech Connect (OSTI)

Nuclear fuel oxidation is an important phenomenon affecting fission product behavior. As indicated by a number of studies, uranium dioxide shows a very wide range of nonstoichiometric states. In steam, fuel oxidation produces a hyperstoichiometric composition, changing the transport properties. Variation of stoichiometry changes diffusion coefficients for oxygen, noble gases, and fission products substantially, affecting the release of fission products.

Dobrov, B.V.; Likhanskii, V.V. [Triniti Research Center, Triniti, Moscow (Russian Federation); Ozrin, V.D. [Nuclear Safety Institute IBREA, Moscow (Russian Federation)] [and others

1997-12-01T23:59:59.000Z

277

Anaerobic Methane Oxidation in a Landfill-Leachate Plume  

E-Print Network [OSTI]

Anaerobic Methane Oxidation in a Landfill-Leachate Plume E T H A N L . G R O S S M A N , * , L U I Landfill, OK, provides an excellent natural laboratory for the study of anaerobicprocessesimpactinglandfill enrichment indicated that 80-90% of the original landfill methane was oxidized over the 210-m transect. First

Grossman, Ethan L.

278

The formation of double-row oxide stripes during the initial oxidation of NiAl(100)  

SciTech Connect (OSTI)

The initial growth of ultrathin aluminum oxide film during the oxidation of NiAl(100) was studied with scanning tunneling microscopy. Our observations reveal that the oxide film grows initially as pairs of a double-row stripe structure with a lateral size equal to the unit cell of ?-Al{sub 2}O{sub 3}. These double-row stripes serve as the very basic stable building units of the ordered oxide phase for growing thicker bulk-oxide-like thin films. It is shown that the electronic properties of these ultrathin double-row stripes do not differ significantly from that of the clean NiAl surface; however, the thicker oxide stripes show a decreased conductivity.

Qin, Hailang; Zhou, Guangwen [Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902 (United States)] [Department of Mechanical Engineering and Multidisciplinary Program in Materials Science and Engineering, State University of New York, Binghamton, New York 13902 (United States)

2013-08-28T23:59:59.000Z

279

Superior catalysts for selective catalytic reduction of nitric oxide. Quarterly technical progress report, January 1, 1995--March 31, 1995  

SciTech Connect (OSTI)

During this quarter, progress was made on the following tasks: TPD techniques were employed to study the reaction mechanism of the selective catalytic reduction of nitrogen oxide with ammonia over iron oxide pillared clay catalyst; and a sulfur dioxide resistant iron oxide/titanium oxide catalyst was developed.

Li, W.B.; Yang, R.T.

1995-12-01T23:59:59.000Z

280

Highly oxidized superconductors  

DOE Patents [OSTI]

Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known synthesis in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed. 16 figs.

Morris, D.E.

1994-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Surface modeling of thin film growth: A study of silicon oxide deposition from tetraethoxysilane and silicon deposition from disilane on the Si(100) surface  

SciTech Connect (OSTI)

In this thesis, surface reactions brought about by the pyrolysis of adsorbed TEOS, the modeling of this reaction with ethanol, and the photolysis of adsorbed disilane have been investigated under ultrahigh vacuum conditions, using mainly temperature programmed desorption (TPD). TEOS molecularly desorbs at about 195K when adsorbed on clean Si(100) at low temperatures. When adsorbed at 300K, the primary surface species produced is a mixture of ethoxysiloxanes. Upon heating the surface in vacuum, the adsorbed ethoxysiloxanes decompose the evolve ethylene and hydrogen, with trace production of acetylene and acetaldehyde. In a parallel study, the adsorption and subsequent deposition of ethanol (C[sub 2]H[sub 5]OH, C[sub 2]D[sub 5]OD, and CH[sub 3]CD[sub 2]OH) on Si(100) has been shown to model the TEOS system. The molecular desorption temperature is ca. 150K. When adsorbed at 200K, ethanol dissociatively chemisorbs as an ethoxide and the monohydride species. The adlayer decomposes at higher temperature to evolve ethylene, hydrogen, acetaldehyde, and acetylene. The adsorption and decomposition of ethanol on Si(100)-2x1:H has also been studied in gathering additional information about the competition between distinct decomposition mechanisms, and the nature of the reaction site. In the Si[sub 2]H[sub 6]/Si(100) system, with no UV irradiation, disilane adsorption at 120K produces a chemisorbed SiH[sub x] (x = 1 - 3) layer and, for high exposures, a disilane multilayer. Upon heating the surface in vacuum, molecular desorption is observed at ca. 150K, while hydrogen and silane are evolved at much higher temperatures. For Si[sub 2]H[sub 6] exposure during photo-irradiation, the desorption yields of hydrogen and silane are enhanced. Model studies using the partially and fully deuterated Si(100)-2x1:D surface reveals that the photo-induced surface reaction is dominated by an insertion reaction by the photo-generated silylene species.

Cho, Hee-Chuen.

1993-01-01T23:59:59.000Z

282

Model approach to solving the inverse problem of X-ray reflectometry and its application to the study of the internal structure of hafnium oxide films  

SciTech Connect (OSTI)

The key features of the inverse problem of X-ray reflectometry (i.e., the reconstruction of the depth profile of the dielectric constant using an experimental angular dependence of reflectivity) are discussed and essential factors leading to the ambiguity of its solution are analyzed. A simple approach to studying the internal structure of HfO{sub 2} films, which is based on the application of a physically reasonable model, is considered. The principles for constructing a film model and the criteria for choosing a minimal number of fitting parameters are discussed. It is shown that the ambiguity of the solution to the inverse problem is retained even for the simplest single-film models. Approaches allowing one to pick out the most realistic solution from several variants are discussed.

Volkov, Yu. O., E-mail: neko.crys@gmail.com; Kozhevnikov, I. V.; Roshchin, B. S. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Filatova, E. O. [St. Petersburg State University, Fock Institute of Physics (Russian Federation)] [St. Petersburg State University, Fock Institute of Physics (Russian Federation); Asadchikov, V. E. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2013-01-15T23:59:59.000Z

283

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2012-09-11T23:59:59.000Z

284

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2014-05-20T23:59:59.000Z

285

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2013-04-16T23:59:59.000Z

286

Ultrafast Graphene Oxide Humidity Sensors  

Science Journals Connector (OSTI)

Ultrafast Graphene Oxide Humidity Sensors ... Graphene oxide can be exploited in humidity and temperature sensors with a number of convenient features such as flexibility, transparency and suitability for large-scale manufacturing. ... Here we show that the two-dimensional nature of graphene oxide and its superpermeability to water combine to enable humidity sensors with unprecedented response speed (?30 ms response and recovery times). ...

Stefano Borini; Richard White; Di Wei; Michael Astley; Samiul Haque; Elisabetta Spigone; Nadine Harris; Jani Kivioja; Tapani Ryhänen

2013-11-09T23:59:59.000Z

287

Doped palladium containing oxidation catalysts  

DOE Patents [OSTI]

A supported oxidation catalyst includes a support having a metal oxide or metal salt, and mixed metal particles thereon. The mixed metal particles include first particles including a palladium compound, and second particles including a precious metal group (PMG) metal or PMG metal compound, wherein the PMG metal is not palladium. The oxidation catalyst may also be used as a gas sensor.

Mohajeri, Nahid

2014-02-18T23:59:59.000Z

288

Inhibition of Oxidation in Nuclear Graphite  

SciTech Connect (OSTI)

Graphite is a fundamental material of high temperature gas cooled nuclear reactors, providing both structure and neutron moderation. Its high thermal conductivity, chemical inertness, thermal heat capacity, and high thermal structural stability under normal and off normal conditions contribute to the inherent safety of these reactor designs. One of the primary safety issues for a high temperature graphite reactor core is the possibility of rapid oxidation of the carbon structure during an off normal design basis event where an oxidizing atmosphere (air ingress) can be introduced to the hot core. Although the current Generation IV high temperature reactor designs attempt to mitigate any damage caused by a postualed air ingress event, the use of graphite components that inhibit oxidation is a logical step to increase the safety of these reactors. Recent experimental studies of graphite containing between 5.5 and 7 wt% boron carbide (B4C) indicate that oxidation is dramatically reduced even at prolonged exposures at temperatures up to 900°C. The proposed addition of B4C to graphite components in the nuclear core would necessarily be enriched in B-11 isotope in order to minimize B-10 neutron absorption and graphite swelling. The enriched boron can be added to the graphite during billet fabrication. Experimental oxidation rate results and potential applications for borated graphite in nuclear reactor components will be discussed.

Phil Winston; James W. Sterbentz; William E. Windes

2013-10-01T23:59:59.000Z

289

Oxidation of carburized Hastelloy X  

SciTech Connect (OSTI)

In a high temperature gas-cooled reactor (HTGR), small quantities of impurities such as H/sub 2/, H/sub 2/O, CO, CO/sub 2/, and CH/sub 4/ are present in the helium coolant. Prolonged exposure to these impurities at high temperature can result in undesirable mechanical properties due to corrosion. Extensive research has been performed on many candidate alloys to study their properties in HTGR helium, and in addition to oxidation, it has been found that carburization is also a possible problem in HTGR. Carbon in the graphite core, carried out by carbon-containing impurities such as CO and CH/sub 4/, can deposit on and diffuse into metallic components and cause carburization. The purpose of this research was to study the effects of carburization on an accelerated test.

Gan, D.

1983-07-01T23:59:59.000Z

290

Effect of microstructure on air oxidation resistance of nuclear graphite  

SciTech Connect (OSTI)

Oxidation resistance in air of three grades of nuclear graphite with different structures was compared using a standard thermogravimetric method. Differences in the oxidation behavior have been identified with respect to both (i) the rate of oxidation in identical conditions and the derived apparent activation energy and pre-exponential factor and (ii) the penetration depth of the oxidant and the development of the oxidized layer. These differences were ascribed to structural differences between the three graphite grades, in particular the grain size and shape of the graphite filler, and the associated textural properties, such as total BET surface area and porosity distribution in the un-oxidized material. It was also found that the amount of strongly bonded surface oxygen complexes measured by thermodesorption significantly exceeds the amount afforded by the low BET surface area, and therefore low temperature oxygen chemisorption is not a reliable method for determining the amount of surface sites (re)active during air oxidation. The relationship between nuclear graphite microstructure and its oxidation resistance demonstrated in this work underlines the importance of performing comprehensive oxidation characterization studies of the new grades of nuclear graphite considered as candidates for very high temperature gas-cooled reactors.

Contescu, Cristian I [ORNL; Guldan, Tyler R [ORNL; Wang, Peng [ORNL; Burchell, Timothy D [ORNL

2012-01-01T23:59:59.000Z

291

Graphene and Graphene Oxide: Biofunctionalization and Applications...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Graphene Oxide: Biofunctionalization and Applications in Biotechnology. Graphene and Graphene Oxide: Biofunctionalization and Applications in Biotechnology. Abstract: Graphene...

292

On the mechanism of the reverse water gas shift reaction: Dynamic TAP reactor studies of the oxidizing capability of CO2 on a Au/CeO2 catalyst  

E-Print Network [OSTI]

of the oxidizing capability of CO2 on a Au/CeO2 catalyst L.C. Wang, M. Tahvildar Khazaneh, D. Widmann, and R the role of the redox mechanism, was investigated by exploring the activity of CO2 for Au assisted CeO2 that the surface reduced Au/CeO2 catalyst can be (partially) re-oxidized by exposure to CO2 pulses, and the surface

Pfeifer, Holger

293

Tungsten oxide nanowire-reduced graphene oxide aerogel for high-efficiency visible light photocatalysis  

Science Journals Connector (OSTI)

Abstract A light, 3-D, porous aerogel was fabricated by way of a simple approach from 1-D tungsten oxide nanowires and 2-D reduced graphene oxide sheets. The as-prepared graphene oxide, tungsten oxide nanowires, and tungsten oxide-reduced graphene oxide (W18O49-RGO) aerogel were characterised. The photocatalytic activities of as-prepared aerogel under visible light irradiation were investigated through the degradation of six different organic dyes including Rhodamine B, reactive black 39, reactive yellow 145, weak acid black BR, methyl orange, and weak acid yellow G. In comparison with the pure W18O49 nanowires, the prepared W18O49-RGO aerogel had significantly improved photocatalytic efficiency. Also, the photocatalysis of W18O49-RGO aerogel maintained its efficiency after 30 cycles for each of the six dyes. The photocatalytic mechanism was studied by adding hole and radical scavengers: the results confirmed that the holes generated in W18O49-RGO aerogel played a key role in the visible light photocatalytic process.

Xiubing Li; Siwei Yang; Jing Sun; Peng He; Xuguang Xu; Guqiao Ding

2014-01-01T23:59:59.000Z

294

Thermodynamic stability of oxide, nitride, and carbide coating materials in liquid Sn25Li  

E-Print Network [OSTI]

Thermodynamic stability of oxide, nitride, and carbide coating materials in liquid Sn­25Li S of various oxides, carbides, and nitrides in Sn­Li is estimated as a function of lithium composition K most of the studied nitrides, carbides, and some oxides were found to be stable (DrG > 0). However

Ghoniem, Nasr M.

295

Aging of Iron (Hydr)oxides by Heat Treatment and Effects on Heavy  

E-Print Network [OSTI]

)oxides are used to remove heavy metals from wastewater and in the treatment of air pollution control residuesAging of Iron (Hydr)oxides by Heat Treatment and Effects on Heavy Metal Binding M E T T E A . S Ã? R generated in waste incineration. In this study, iron oxides containing heavy metals (e.g., Pb, Hg, Cr

Frenkel, Anatoly

296

The Effect of an Axial Catalyst Distribution on the Performance of a Diesel Oxidation Catalyst and Inverse Hysteresis Phenomena during CO and C3H6 Oxidation.  

E-Print Network [OSTI]

??The Diesel Oxidation Catalyst (DOC) is a key component in the exhaust after-treatment system of diesel engines. In this study two aspects of a DOC… (more)

Abedi, Ali

2012-01-01T23:59:59.000Z

297

Interfacial oxide re-growth in thin film metal oxide III-V semiconductor systems  

SciTech Connect (OSTI)

The Al{sub 2}O{sub 3}/GaAs and HfO{sub 2}/GaAs interfaces after atomic layer deposition are studied using in situ monochromatic x-ray photoelectron spectroscopy. Samples are deliberately exposed to atmospheric conditions and interfacial oxide re-growth is observed. The extent of this re-growth is found to depend on the dielectric material and the exposure temperature. Comparisons with previous studies show that ex situ characterization can result in misleading conclusions about the interface reactions occurring during the metal oxide deposition process.

McDonnell, S.; Dong, H.; Hawkins, J. M.; Brennan, B.; Milojevic, M.; Aguirre-Tostado, F. S.; Zhernokletov, D. M.; Hinkle, C. L.; Kim, J.; Wallace, R. M.

2012-04-02T23:59:59.000Z

298

Enrichment of Fe and Ni at metal and oxide grain boundaries in corroded Zircaloy-2  

Science Journals Connector (OSTI)

Atom probe tomography has been used to study for the first time the metal–oxide interface region in Zircaloy-2. Segregation of Fe and Ni to both deformation-induced sub-grain boundaries in the metal and planar features in the oxide has been found. Apparently, the oxide inherits the chemistry of the sub-grain boundaries as the material oxidizes, which may have implications for the waterside corrosion kinetics of the alloy.

G. Sundell; M. Thuvander; H.-O. Andrén

2012-01-01T23:59:59.000Z

299

Micro-arc oxidation coatings on Mg-Li alloys  

Science Journals Connector (OSTI)

Micro-arc oxidation (MAO) method was used for the...in-situ fabricated on the Mg-Li alloy. The morphology feature, phase composition, and corrosion-resistance of the formed ceramic coatings were studied by SEM, X...

Yongjun Xu; Kang Li; Zhongping Yao; Zhaohua Jiang; Milin Zhang

2009-04-01T23:59:59.000Z

300

Nanostructured thin films for solid oxide fuel cells  

E-Print Network [OSTI]

The goals of this work were to synthesize high performance perovskite based thin film solid oxide fuel cell (TF-SOFC) cathodes by pulsed laser deposition (PLD), to study the structural, electrical and electrochemical properties of these cathodes...

Yoon, Jongsik

2009-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

The explosive oxidation of hydrocarbons in a supercritical water  

Science Journals Connector (OSTI)

The kinetics of oxidation of naphthalene and a heavy oil residue (upon vacuum distillation) by oxygen dissolved in supercritical water is studied in a wide range of temperatures (663 K?T?1075 K) and pressures (31...

A. A. Vostrikov; S. A. Psarov

2002-09-01T23:59:59.000Z

302

Oxidation resistant alloys, method for producing oxidation resistant alloys  

DOE Patents [OSTI]

A method for producing oxidation-resistant austenitic alloys for use at temperatures below 800.degree. C. comprising of: providing an alloy comprising, by weight %: 14-18% chromium, 15-18% nickel, 1-3% manganese, 1-2% molybdenum, 2-4% silicon, 0% aluminum and the balance being iron; heating the alloy to 800.degree. C. for between 175-250 hours prior to use in order to form a continuous silicon oxide film and another oxide film. The method provides a means of producing stainless steels with superior oxidation resistance at temperatures above 700.degree. C. at a low cost

Dunning, John S. (Corvallis, OR); Alman, David E. (Salem, OR)

2002-11-05T23:59:59.000Z

303

Oxidation resistant alloys, method for producing oxidation resistant alloys  

DOE Patents [OSTI]

A method for producing oxidation-resistant austenitic alloys for use at temperatures below 800 C. comprising of: providing an alloy comprising, by weight %: 14-18% chromium, 15-18% nickel, 1-3% manganese, 1-2% molybdenum, 2-4% silicon, 0% aluminum and the balance being iron; heating the alloy to 800 C. for between 175-250 hours prior to use in order to form a continuous silicon oxide film and another oxide film. The method provides a means of producing stainless steels with superior oxidation resistance at temperatures above 700 C. at a low cost

Dunning, John S.; Alman, David E.

2002-11-05T23:59:59.000Z

304

Catalyst Additives to Enhance Mercury Oxidation and Capture  

SciTech Connect (OSTI)

Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. Three different SCR catalysts are currently being studied in this project--honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts were manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Parametric testing was performed to investigate the contribution of flue-gas chemistry on mercury oxidation via SCR catalysts. Future work to characterize flue gas simulations typically derived from low and high sulfur bituminous coal are being performed in a stepwise manner, to avoid the constant interruptions in testing that occur when leaks in the system are generated during temperature transitions. Specifically, chlorine concentration vs. mercury oxidation correlations will be developed for each catalyst. The contributions of temperature are also being investigated. SO2 oxidation is also being investigated for each test condition.

Thomas K. Gale

2005-12-31T23:59:59.000Z

305

Temperature dependence of structural parameters in oxide-ion-conducting Nd{sub 9.33}(SiO{sub 4}){sub 6}O{sub 2}: single crystal X-ray studies from 295 to 900K  

SciTech Connect (OSTI)

Crystallographic space group, structural parameters and their thermal changes in oxide-ion-conducting Nd{sub 9.33}(SiO{sub 4}){sub 6}O{sub 2} were investigated using high-temperature single-crystal X-ray diffraction experiments in the temperature range of 295=oxide ions which belong to SiO{sub 4} tetrahedron indicated high rigidity of the tetrahedron in the structure, indicating that they form sp3 hybrid orbitals and the ligand oxygens do not take part in oxide-ion conductivity. Virtually full occupation of the 6h Nd site and highly anisotropic displacements of oxide ion inside the hexagonal channel were maintained over the temperature range examined. This result confirms that oxide-ion transport inside the hexagonal channel is the dominant process of conduction in the title compound.

Okudera, Hiroki [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, DE-70569 Stuttgart (Germany)]. E-mail: h.okudera@fkf.mpg.de; Yoshiasa, Akira [Department of Earth and Space Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043 (Japan); Masubuchi, Yuuji [Material Science and Engineering, Graduate School of Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Higuchi, Mikio [Material Science and Engineering, Graduate School of Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Kikkawa, Shinichi [Material Science and Engineering, Graduate School of Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan)

2004-12-01T23:59:59.000Z

306

A combined ToF-SIMS and XPS study for the elucidation of the role of water in the performances of a Post-Plasma Process using LaMnO3+? as catalyst in the total oxidation of trichloroethylene  

Science Journals Connector (OSTI)

Abstract LaMnO3+? which is an environment-friendly and inexpensive material has been previously used as catalyst in Post-Plasma Catalysis (PPC) in the total oxidation of trichloroethylene (TCE) which is a solvent widely used in dry cleaning and degreasing processes. It has been shown that the process efficiency increases in moist air (RH = 18%).The issue we want to address herein is the effect of water on the location of chlorine at the surface of the catalyst as chlorine is able to alter the catalyst structure, activity and stability. Therefore, a combined Time of Flight-Secondary Ion Mass Spectrometry (ToF-SIMS) and X-ray Photoelectron Spectroscopy (XPS) study has been carried out on the fresh LaMnO3+? catalyst (LM) and used catalysts after performing PPC with TCE diluted in dry synthetic air (LM0) or with industrial air containing water (LM18; 18 stands for the Relative Humidity) and CO2 (about 560 ppmv) at a temperature of 150 °C. XPS and ToF-SIMS results both show the presence of chlorine on the tested catalysts whose amount increases by exposure of the catalyst to the reactive mixture in dry synthetic air. XPS results reveal that chlorine is present as both chloride ion and covalent chlorine on LM0 while organic chlorinated residues are absent on LM18 catalyst. ToF-SIMS study indicates that lanthanum excess as oxide(hydroxide) partially covering the perovskite mainly transforms into LaOCl and to a minor extent into LaCl3. Extent of Mn chlorination seems to be favored over LM0 having a higher MnClx±/MnOCl± ionic ratio compared to LM18. Furthermore ToF-SIMS clearly identifies C1 chlorinated organic ions, mainly CH2Cl+ and CHCl2?, on LM0 which may contribute to the XPS Cl organic component. From the combined ToF-SIMS and XPS results it is found that water delays the surface degradation extent of the perovskite into related (oxy)(hydroxy)chlorinated inorganic phases by less molecular chlorine and related chlorine species on the catalyst surface. A reaction scheme of Cl removal over LaMnO3+? emphasing the role of water is given taking into account the detection of ToF-SIMS ions representative of the successive Mn intermediate states. As a consequence water allows tuning the degradation pathways of the main intermediate of the reaction, dichloroacetyl chloride (DCAC), which decomposes to give phosgene, \\{HCCl3\\} and \\{CCl4\\} by a successive Cl incorporation over (oxy)(hydroxy)chorinated perovskite or/and Mn species while \\{COx\\} species are likely formed over the perovskite.

N. Nuns; A. Beaurain; M.T. Nguyen Dinh; A. Vandenbroucke; N. De Geyter; R. Morent; C. Leys; J.-M. Giraudon; J.-F. Lamonier

2014-01-01T23:59:59.000Z

307

Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction for Lithium-Ion Battery Application Title Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction for Lithium-Ion Battery Application Publication Type Journal Article Year of Publication 2011 Authors Xun, Shidi, Xiangyun Song, Michael E. Grass, Daniel K. Roseguo, Z. Liu, Vincent S. Battaglia, and Gao Li Journal Electrochemical Solid-State Letters Volume 14 Start Page A61 Issue 5 Pagination A61-A63 Date Published 02/2001 Keywords Electrochemistry, elemental semiconductors, etching, lithium, nanoparticles, secondary cells, silicon, thermal analysis, transmission electron microscopy, X-ray photoelectron spectra Abstract This study characterizes the native oxide layer of Si nanoparticles and evaluates its effect on their performance for Li-ion batteries. x-ray photoelectron spectroscopy and transmission electron microscopy were applied to identify the chemical state and morphology of the native oxide layer. Elemental and thermogravimetric analysis were used to estimate the oxide content for the Si samples. Hydrofluoric acid was used to reduce the oxide layer. A correlation between etching time and oxide content was established. The initial electrochemical performances indicate that the reversible capacity of etched Si nanoparticles was enhanced significantly compared with that of the as-received Si sample.

308

Surface characterization and mechanical property evaluation of thermally oxidized Ti-6Al-4V  

SciTech Connect (OSTI)

The present study concerns development of a thin and adherent oxide film on the surface of Ti-6Al-4V by thermal oxidation. Thermal oxidation was carried out over a range of temperature between 400 to 600 deg. C and a time from 25 h to 60 h. A detailed characterization of the surface and cross section of the oxidized surface was carried out by optical/scanning electron microscopy and X-ray diffraction techniques. Finally, the mechanical properties of the oxidized surface in terms of microindentation hardness and wear resistance were evaluated as a function of oxidation parameters. Surface oxidation of Ti-6Al-4V at 600 deg. C for 36 h offered a defect free oxide scale with improved hardness and wear resistance.

Biswas, Amit [Department of Metal. and Maters. Engg., I. I. T. Kharagpur, W. B. - 721302 (India); Dutta Majumdar, Jyotsna, E-mail: jyotsna@metal.iitkgp.ernet.in [Department of Metal. and Maters. Engg., I. I. T. Kharagpur, W. B. - 721302 (India)

2009-06-15T23:59:59.000Z

309

Enhanced Thermal Conductivity Oxide Fuels  

SciTech Connect (OSTI)

the purpose of this project was to investigate the feasibility of increasing the thermal conductivity of oxide fuels by adding small fractions of a high conductivity solid phase.

Alvin Solomon; Shripad Revankar; J. Kevin McCoy

2006-01-17T23:59:59.000Z

310

Anodic oxidation of zircaloy-2  

Science Journals Connector (OSTI)

The anodic polarization of zircaloy-2 in different electrolytic baths has been investigated in order to obtain thick oxide films with properties suitable for wear applications.

A. Conte; A. Borello; A. Cabrini

1976-07-01T23:59:59.000Z

311

Structure, adhesion, and stability of metal/oxide and oxide/oxide interfaces. Technical progress report, August 1, 1992--July 31, 1993  

SciTech Connect (OSTI)

Studies of structural, electronic, and chemical properties of metal/oxide and oxide/oxide interfaces were performed on well-defined interfaces that created by depositing ultra-thin potassium and aluminum films and their oxides onto single crystal TiO{sub 2} and NiO surfaces. Work focused on determining the structure, growth mechanisms, and morphologies of metal and oxide films as they are deposited an single crystal oxide surfaces using RHEED and atomic force microscopy probing electronic structure, bonding and chemical interactions at the interfaces using x-ray and uv photoelectron spectroscopies (XPS, UPS) and Auger electron spectroscopy (AES), and understanding factors affecting stability and reactivity of the interface regions including the role of defects and impurities. Results indicate that kinetic effects have an important influence on interface structure and composition, and they also show that defects in the oxide substrate induce new electronic states at the interface which play a major role in cation-anion bonding and interface interactions. The results establish a link between electronic and chemical bonding properties and the interface structure and morphology, which is required to successfully manipulate the interfacial properties of advanced ceramic materials.

Lad, R.J.

1992-11-01T23:59:59.000Z

312

Oxidized low density lipoprotein increases RANKL level in human vascular cells. Involvement of oxidative stress  

SciTech Connect (OSTI)

Highlights: •Oxidized LDL enhances RANKL level in human smooth muscle cells. •The effect of OxLDL is mediated by the transcription factor NFAT. •UVA, H{sub 2}O{sub 2} and buthionine sulfoximine also increase RANKL level. •All these effects are observed in human fibroblasts and endothelial cells. -- Abstract: Receptor Activator of NF?B Ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) have been shown to play a role not only in bone remodeling but also in inflammation, arterial calcification and atherosclerotic plaque rupture. In human smooth muscle cells, Cu{sup 2+}-oxidized LDL (CuLDL) 10–50 ?g/ml increased reactive oxygen species (ROS) and RANKL level in a dose-dependent manner, whereas OPG level was not affected. The lipid extract of CuLDL reproduced the effects of the whole particle. Vivit, an inhibitor of the transcription factor NFAT, reduced the CuLDL-induced increase in RANKL, whereas PKA and NF?B inhibitors were ineffective. LDL oxidized by myeloperoxidase (MPO-LDL), or other pro-oxidant conditions such as ultraviolet A (UVA) irradiation, incubation with H{sub 2}O{sub 2} or with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis{sub ,} also induced an oxidative stress and enhanced RANKL level. The increase in RANKL in pro-oxidant conditions was also observed in fibroblasts and endothelial cells. Since RANKL is involved in myocardial inflammation, vascular calcification and plaque rupture, this study highlights a new mechanism whereby OxLDL might, by generation of an oxidative stress, exert a deleterious effect on different cell types of the arterial wall.

Mazière, Cécile, E-mail: maziere.cecile@chu-amiens.fr [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France)] [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France); Salle, Valéry [Internal Medicine, North Hospital University, Place Victor Pauchet, Amiens 80000 (France) [Internal Medicine, North Hospital University, Place Victor Pauchet, Amiens 80000 (France); INSERM U1088 (EA 4292), SFR CAP-Santé (FED 4231), University of Picardie – Jules Verne (France); Gomila, Cathy; Mazière, Jean-Claude [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France)] [Biochemistry Laboratory, South Hospital University, René Laennec Avenue, Amiens 80000 (France)

2013-10-18T23:59:59.000Z

313

Spectroscopic ellipsometry of electrochemical precipitation and oxidation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Spectroscopic ellipsometry of electrochemical precipitation and oxidation Spectroscopic ellipsometry of electrochemical precipitation and oxidation of nickel hydroxide films Title Spectroscopic ellipsometry of electrochemical precipitation and oxidation of nickel hydroxide films Publication Type Journal Article Year of Publication 1998 Authors Kong, Fanping, Robert Kostecki, Frank R. McLarnon, and Rolf H. Muller Journal Thin Solid Films Volume 313-314 Pagination 775-780 Keywords effective medium approximation, electrochemical precipitation, inhomogeneous films, nickel hydroxide, spectroscopic ellipsometry Abstract In situ spectroscopic ellipsometry was used to investigate the electrochemical precipitation of nickel hydroxide films. By use of optical models for inhomogeneous films it was found that a specific precipitation current density produced the most compact and homogeneous film structures. The density of nickel hydroxide films was derived to be 1.25-1.50 g/cm3. The redox behavior of precipitated nickel hydroxide films was studied with an effective-medium optical model. Incomplete conversion to nickel oxyhydroxide and a reduction in film thickness were found during the oxidation cycle.

314

Comparison of lipid oxidation, iron catalysts, and flavor deterioration in beef, chicken, and pork  

E-Print Network [OSTI]

to flavor deterioration in stored meat Reported studies indicate that susceptibility of muscle tissue to undergo lipid oxidation differs among meat animal species. However, the species effect is not consistent among research studies reported... to assess lipid oxidation. The objectives of this study were to compare lipid oxidation and flavor deterioration potential of beef, pork, and chicken muscles with the aforementioned experimental variables controlled. In addition, nonheme and heme iron...

Burchell, Lisa Michelle

1992-01-01T23:59:59.000Z

315

Operation of staged membrane oxidation reactor systems  

SciTech Connect (OSTI)

A method of operating a multi-stage ion transport membrane oxidation system. The method comprises providing a multi-stage ion transport membrane oxidation system with at least a first membrane oxidation stage and a second membrane oxidation stage, operating the ion transport membrane oxidation system at operating conditions including a characteristic temperature of the first membrane oxidation stage and a characteristic temperature of the second membrane oxidation stage; and controlling the production capacity and/or the product quality by changing the characteristic temperature of the first membrane oxidation stage and/or changing the characteristic temperature of the second membrane oxidation stage.

Repasky, John Michael

2012-10-16T23:59:59.000Z

316

Catalytic wet oxidation of phenolic wastes  

E-Print Network [OSTI]

Possible catalyst deactivation problems High capital, low operating Supercritical water oxidation (SCWO) Feasible only at high organic concentra- tions High Fast reaction, complete oxidation Severe reaction conditions, canosion problems... of milder reaction conditions and is much less energy intensive. Thus, catalytic wet oxidation would be an alternative to solvent extraction, supercritical water oxidation, homogeneous oxidation, and incineration. It should also be feasible at low...

Thomas, Brook James

1995-01-01T23:59:59.000Z

317

Low Temperature Constrained Sintering of Cerium Gadolinium Oxide Films for Solid Oxide Fuel Cell Applications  

E-Print Network [OSTI]

Temperature Solid Oxide Fuel Cells, In: S.C. Singhal and M.solidoxide.html, Tubular Solid Oxide Fuel Cell Technology,Oxide Films for Solid Oxide Fuel Cell Applications by Jason

Nicholas, Jason.D.

2007-01-01T23:59:59.000Z

318

Catalytic oxidation of ethyl acetate over La-Co and La-Cu oxides  

Science Journals Connector (OSTI)

Abstract Lanthanum-containing mixed oxides (La-Co and La-Cu) were synthesized by several methods: exotemplating, evaporation, glycine-nitrate and glycine-nitrate-exotemplating. Samples were characterized by thermogravimetry and differential scanning calorimetry, N2 adsorption, temperature programmed reduction, scanning electron microscopy and X-ray diffraction. The materials obtained were tested as catalysts for ethyl acetate oxidation, as a model volatile organic compound. La-Cu samples showed poor catalytic performance, but La-Co materials were much more active than the individual components. Catalytic activity seems to be mainly determined by the easiness of reduction of the catalysts, which is related to the availability of oxygen from the lattice. Catalysts containing Co or Cu in excess of La (on a molar base) were more active than the corresponding mixed oxides consisting of equal amounts of La and the transition metal. Samples prepared by the evaporation method were more active than those prepared by exotemplating, for the same molar ratio. Samples prepared by evaporation and glycine-nitrate methods calcined at 600 °C had a better performance than the corresponding oxides calcined at 300 °C. The most active sample found in this study was the La-Co mixed oxide prepared by the glycine nitrate method and calcined at 600 °C, 100% conversion of ethyl acetate to H2O and CO2 being achieved at 230 °C.

X. Chen; S.A.C. Carabineiro; P.B. Tavares; J.J.M. Órfão; M.F.R. Pereira; J.L. Figueiredo

2014-01-01T23:59:59.000Z

319

Graphene oxide-based micropatterns via high-throughput multiphoton-induced reduction and ablation  

Science Journals Connector (OSTI)

In this study, a developed temporal focusing-based femtosecond laser system provides high-throughput multiphoton-induced reduction and ablation of graphene oxide (GO) films. Integrated...

Li, Yi-Cheng; Yeh, Te-Fu; Huang, Hsin-Chieh; Chang, Hsin-Yu; Lin, Chun-Yu; Cheng, Li-Chung; Chang, Chia-Yuan; Teng, Hsisheng; Chen, Shean-Jen

2014-01-01T23:59:59.000Z

320

Origin of The 871-keV Gamma Ray and the "Oxide" Attribute  

SciTech Connect (OSTI)

This brief paper concludes our study of the origin of the 871-keV observed for many plutonium oxide samples.

Peurrung, Anthony J.; Arthur, Richard J.; Geelhood, Bruce D.; Scheele, Randall D.; Elovich, Robert J.; Pratt, Sharon L.

2000-03-22T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

FACTORS CONTROLLING SYNTHESIS OF IRON OXIDE NANOPARTICLES AND THE EFFECT OF SURFACE CHARGE ON MAGNETIC HYPERTHERMIA.  

E-Print Network [OSTI]

??ABSTRACT Iron oxide nanoparticles (IONPs) have been widely studied in the theranostics application due to their promising magnetic properties, low cytotoxicity and attractive biocompatibility. Despite… (more)

Qi, Bin

2013-01-01T23:59:59.000Z

322

Iron oxide nanoparticle-based theranostics for cancer imaging and therapy  

Science Journals Connector (OSTI)

Theranostic platform, which is equipped with both diagnostic and therapeutic functions, is a promising approach in cancer treatment. From various nanotheranostics studied, iron oxide nanoparticles have advantages...

Xiaoqing Ren; Hongwei Chen; Victor Yang…

2014-09-01T23:59:59.000Z

323

Oxidation induced localized creep deformation in Zircaloy-2  

Science Journals Connector (OSTI)

Abstract Extensive plastic deformation in the metal underneath the oxide scale in autoclave tested Zircaloy-2 was studied using transmission electron microscopy (TEM). It was concluded that the plastic deformation is created by creep during oxidation, and is not caused by surface treatment, sample preparation or cooling from autoclave temperatures. Evidence of large strains was found in the form of dislocation tangles, dislocation patches and sub-grain formation, and also indications of twinning were found. The heavily deformed layer is around a few ?m thick and no obvious difference could be seen between alloys with different strength or different oxide thickness.

Pia Tejland; Hans-Olof Andrén

2014-01-01T23:59:59.000Z

324

Metal oxide films on metal  

DOE Patents [OSTI]

A structure including a thin film of a conductive alkaline earth metal oxide selected from the group consisting of strontium ruthenium trioxide, calcium ruthenium trioxide, barium ruthenium trioxide, lanthanum-strontium cobalt oxide or mixed alkaline earth ruthenium trioxides thereof upon a thin film of a noble metal such as platinum is provided.

Wu, Xin D. (Los Alamos, NM); Tiwari, Prabhat (Los Alamos, NM)

1995-01-01T23:59:59.000Z

325

Ethylene Oxide for Soil Sterilization  

Science Journals Connector (OSTI)

... , this method may be time-consuming, and in view of the physical properties of ethylene oxide (solubility in water and boiling point 12-5 C.) it was considered ... consists of making up an aqueous solution to supply 2 or 4 c.c. of ethylene oxide in a given amount of water, using pre-chilled glassware and water. The ...

R. E. ROSE; R. W. BAILEY

1952-04-26T23:59:59.000Z

326

Ultra Supercritical Steamside Oxidation  

SciTech Connect (OSTI)

Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions, which are goals of the U.S. Department of Energy's Advanced Power Systems Initiatives. Most current coal power plants in the U.S. operate at a maximum steam temperature of 538 C. However, new supercritical plants worldwide are being brought into service with steam temperatures of up to 620 C. Current Advanced Power Systems goals include coal generation at 60% efficiency, which require steam temperatures of up to 760 C. This research examines the steamside oxidation of advanced alloys for use in USC systems, with emphasis placed on alloys for high- and intermediate-pressure turbine sections. Initial results of this research are presented.

Holcomb, Gordon R.; Cramer, Stephen D.; Covino, Bernard S., Jr.; Bullard, Sophie J.; Ziomek-Moroz, Malgorzata

2005-01-01T23:59:59.000Z

327

Nanostructured Solid Oxide Fuel Cell Electrodes  

E-Print Network [OSTI]

post-Doping of Solid Oxide Fuel Cell Cathodes,? P.h.D.and V. I. Birss, in Solid Oxide Fuel Cells (SOFC IX), S. C.Nanostructured Solid Oxide Fuel Cell Electrodes By Tal Zvi

Sholklapper, Tal Zvi

2007-01-01T23:59:59.000Z

328

Detection of oxidation in human serum lipoproteins  

E-Print Network [OSTI]

A method for the oxidation of lipoproteins in vitro was developed using the free radical initiator, 2,2?-azobis-(2-amidinopropane) dihydrochloride (AAPH). Following in vitro oxidation, the susceptibility to oxidation of the serum samples...

Myers, Christine Lee

2006-04-12T23:59:59.000Z

329

Development of Nitric Oxide Oxidation Catalysts for the Fast SCR Reaction  

SciTech Connect (OSTI)

This study was undertaken in order to assess the potential for oxidizing NO to NO{sub 2} in flue gas environments, with the aim of promoting the so-called fast SCR reaction. In principle this can result in improved SCR kinetics and reduced SCR catalyst volumes. Prior to commencing experimental work, a literature study was undertaken to identify candidate catalysts for screening. Selection criteria comprised (1) proven (or likely) activity for NO oxidation, (2) low activity for SO2 oxidation (where data were available), and (3) inexpensive component materials. Catalysts identified included supported base metal oxides, supported and unsupported mixed metal oxides, and metal ion exchanged ZSM-5 (Fe, Co, Cu). For comparison purposes, several low loaded Pt catalysts (0.5 wt% Pt) were also included in the study. Screening experiments were conducted using a synthetic feed gas representative of flue gas from coal-fired utility boilers: [NO] = 250 ppm, [SO{sub 2}] = 0 or 2800 ppm, [H{sub 2}O] = 7%, [CO{sub 2}] = 12%, [O{sub 2}] = 3.5%, balance = N{sub 2}; T = 275-375 C. Studies conducted in the absence of SO{sub 2} revealed a number of supported and unsupported metal oxides to be extremely active for NO oxidation to NO{sub 2}. These included known catalysts (Co{sub 3}O{sub 4}/SiO{sub 2}, FeMnO{sub 3}, Cr{sub 2}O{sub 3}/TiO{sub 2}), as well as a new one identified in this work, CrFeO{sub x}/SiO{sub 2}. However, in the presence of SO{sub 2}, all the catalysts tested were found to be severely deactivated with respect to NO oxidation. Of these, Co{sub 3}O{sub 4}/SiO{sub 2}, Pt/ZSM-5 and Pt/CeO{sub 2} showed the highest activity for NO oxidation in the presence of SO{sub 2} (based on peak NO conversions to NO{sub 2}), although in no cases did the NO conversion exceed 7%. Reactor studies indicate there are two components to SO{sub 2}-induced deactivation of Co{sub 3}O{sub 4}/SiO{sub 2}, corresponding to an irreversible deactivation due to sulfation of the surface of the Co{sub 3}O{sub 4} phase, together with a reversible inhibition due to competitive adsorption of SO{sub 2} with NO on the catalyst. In an effort to minimize the deactivating effect of SO{sub 2} on Co{sub 3}O{sub 4}/SiO{sub 2}, two synthetic approaches were briefly examined. These consisted of (1) the incorporation of highly dispersed Co(II) ions in silica, as a non-sulfating matrix, via the sol-gel preparation of CoO-SiO{sub 2}; and (2) the sol-gel preparation of a mixed metal oxide, CoO-Nb{sub 2}O{sub 5}-SiO{sub 2}, with the aim of exploiting the acidity of the niobium oxide to minimize SO2 adsorption. While both catalysts showed almost no activity for NO oxidation in the absence of SO{sub 2}, when SO{sub 2} was present low activity was observed, indicating that SO{sub 2} acts as a promoter for NO oxidation over these materials. The kinetics of NO oxidation over Co{sub 3}O{sub 4}/SiO{sub 2}, Pt/SiO{sub 2} and Pt/CeO{sub 2} were also examined. Co{sub 3}O{sub 4}/SiO{sub 2} was found to exhibit a higher apparent activation energy for NO oxidation than the Pt catalysts, while the combined reaction order in NO and O{sub 2} for the three catalysts was very close to one. CO{sub 2} was found to have no effect on the kinetics of NO oxidation over these catalysts. The presence of H{sub 2}O caused a decrease in NO conversion for both Co{sub 3}O{sub 4}/SiO{sub 2} and Pt/CeO{sub 2} catalysts, while no effect was observed for Pt/SiO{sub 2}. The inhibiting effect of water was reversible and is attributed to competitive adsorption with the reactants. In sum, this study has shown that a variety of base metal catalysts are very active for NO oxidation. However, all of the catalysts studied are strongly deactivated in the presence of 2800 ppm SO{sub 2} at typical flue gas temperatures; consequently improving catalyst resistance to SO{sub x} will be a pre-requisite if the fast SCR concept is to be applied to coal-fired flue gas conditions.

Mark Crocker

2005-09-30T23:59:59.000Z

330

New manganese catalyst for light alkane oxidation  

DOE Patents [OSTI]

Aluminophosphates containing manganese in the structural framework are employed for the oxidation of alkanes, for example the vapor phase oxidation of methane to methanol.

Durante, Vincent A. (West Chester, PA); Lyons, James E. (Wallingford, PA); Walker, Darrell W. (Visalia, CA); Marcus, Bonita K. (Radnor, PA)

1994-01-01T23:59:59.000Z

331

Study of the effect of the acid-base surface properties of ZnO, Fe{sub 2}O{sub 3} and ZnFe{sub 2}O{sub 4} oxides on their gas sensitivity to ethanol vapor  

SciTech Connect (OSTI)

Binary (ZnO, Fe{sub 2}O{sub 3}) and ternary (ZnFe{sub 2}O{sub 4}) gas-sensitive oxide materials are synthesized, and the correlation between their sensitivity to ethanol vapor and the functional chemical composition of the surface is studied by X-ray photoelectron spectroscopy and by the technique of the adsorption of acid-base indicators. It is found that the sensitivity to ethanol increases with increasing content of Broensted acid sites with the acidity index pK{sub a} Almost-Equal-To 2.5 and with increasing percentage of surface oxygen involved in OH/CO{sub 3}/C-O groups. This interrelation is attributed to the specific features of interaction between ethanol molecules and hydroxyl groups on the surface of the oxides.

Karpova, S. S., E-mail: sskarpova@list.ru; Moshnikov, V. A.; Maksimov, A. I. [St. Petersburg State Electrotechnical University 'LETI' (Russian Federation)] [St. Petersburg State Electrotechnical University 'LETI' (Russian Federation); Mjakin, S. V. [St. Petersburg State Institute of Technology (Technical University) (Russian Federation)] [St. Petersburg State Institute of Technology (Technical University) (Russian Federation); Kazantseva, N. E. [Tomas Bata University in Zlin (Czech Republic)] [Tomas Bata University in Zlin (Czech Republic)

2013-08-15T23:59:59.000Z

332

DEVELOPMENT OF STRAIN IN OXIDES GROWN IN STEAM TUBES  

SciTech Connect (OSTI)

In this study, the foundation is being developed for the numerical simulation of the processes that determine the oxide scale exfoliation behavior of the steam-side surfaces of superheater and reheater tubes in a steam boiler. Initially, the assumptions concerning the base state for calculating oxide strains also were critically examined. The state of stress-strain of an oxide growing on the inside surface of an externally-heated tube was considered for the conditions experienced in a boiler during transition from full- to partial-load operation. Since the rate at which the oxide grows is an important consideration, it was necessary to determine the appropriate temperature to use in the oxidation rate calculations. The existence of a temperature gradient through the tube, and the cyclic nature of the boiler operation (temperature and pressure) were considered; the growth temperature of the oxide was taken to be the oxide surface temperature. It was determined that the commonly-used approach for accounting for geometrical effects when calculating stress-strain development in a growing oxide scale of using the analogy of an infinitely-long flat plate gave sufficiently different results than when using a cylindrical geometry, that the latter was adopted as the preferred calculation procedure. Preliminary calculation of strains developed in multilayered oxides formed on alloy T22 as a function of boiler operating conditions indicated the magnitude of the strains in each layer; the large strain gradients between the layers inferred the importance of the detailed scale morphology in determining the mode of exfoliation

Wright, Ian G [ORNL] [ORNL; Sabau, Adrian S [ORNL] [ORNL; Dooley, Barry [Electric Power Research Institute (EPRI)] [Electric Power Research Institute (EPRI)

2008-01-01T23:59:59.000Z

333

Process for light-driven hydrocarbon oxidation at ambient temperatures  

DOE Patents [OSTI]

A photochemical reaction for the oxidation of hydrocarbons uses molecular oxygen as the oxidant. A reductive photoredox cycle that uses a tin(IV)- or antimony(V)-porphyrin photosensitizer generates the reducing equivalents required to activate oxygen. This artificial photosynthesis system drives a catalytic cycle, which mimics the cytochrome P.sub.450 reaction, to oxidize hydrocarbons. An iron(III)- or manganese(III)-porphyrin is used as the hydrocarbon-oxidation catalyst. Methylviologen can be used as a redox relay molecule to provide for electron-transfer from the reduced photosensitizer to the Fe or Mn porphyrin. The system is long-lived and may be used in photo-initiated spectroscopic studies of the reaction to determine reaction rates and intermediates.

Shelnutt, John A. (Tijeras, NM)

1990-01-01T23:59:59.000Z

334

Proceedings of the Lucerne Fuel Cell Forum 2006 European Solid Oxide Fuel Cell Forum, 3-7 July 2006  

E-Print Network [OSTI]

Proceedings of the Lucerne Fuel Cell Forum 2006 7th European Solid Oxide Fuel Cell Forum, 3-7 July Uncertainties in our understanding of the oxygen reduction mechanism (ORR) at solid oxide fuel cell (SOFC studies have shown that cathodic or anodic dc polarization of the solid oxide fuel cell oxygen electrodes

Yildiz, Bilge

335

Emergent Phenomena at Oxide Interfaces  

SciTech Connect (OSTI)

Transition metal oxides (TMOs) are an ideal arena for the study of electronic correlations because the s-electrons of the transition metal ions are removed and transferred to oxygen ions, and hence the strongly correlated d-electrons determine their physical properties such as electrical transport, magnetism, optical response, thermal conductivity, and superconductivity. These electron correlations prohibit the double occupancy of metal sites and induce a local entanglement of charge, spin, and orbital degrees of freedom. This gives rise to a variety of phenomena, e.g., Mott insulators, various charge/spin/orbital orderings, metal-insulator transitions, multiferroics, and superconductivity. In recent years, there has been a burst of activity to manipulate these phenomena, as well as create new ones, using oxide heterostructures. Most fundamental to understanding the physical properties of TMOs is the concept of symmetry of the order parameter. As Landau recognized, the essence of phase transitions is the change of the symmetry. For example, ferromagnetic ordering breaks the rotational symmetry in spin space, i.e., the ordered phase has lower symmetry than the Hamiltonian of the system. There are three most important symmetries to be considered here. (i) Spatial inversion (I), defined as r {yields} -r. In the case of an insulator, breaking this symmetry can lead to spontaneous electric polarization, i.e. ferroelectricity, or pyroelectricity once the point group belongs to polar group symmetry. (ii) Time-reversal symmetry (T) defined as t {yields} -t. In quantum mechanics, the time-evolution of the wave-function {Psi} is given by the phase factor e{sup -iEt/{h_bar}} with E being the energy, and hence time-reversal basically corresponds to taking the complex conjugate of the wave-function. Also the spin, which is induced by the 'spinning' of the particle, is reversed by time-reversal. Broken T-symmetry is most naturally associated with magnetism, since the spin operator changes sign with T-operation. (iii) Gauge symmetry (G), which is associated with a change in the phase of the wave-function as {Psi} {yields} e{sup i{theta}}{Psi}. Gauge symmetry is connected to the law of charge conservation, and broken G-symmetry corresponds to superconductivity/superfluidity. To summarize, the interplay among these electronic degrees of freedom produces various forms of symmetry breaking patterns of I, T, and G, leading to novel emergent phenomena, which can appear only by the collective behavior of electrons and cannot be expected from individual electrons. Figure 1 shows this schematically by means of several representative phenomena. From this viewpoint, the interfaces of TMOs offer a unique and important laboratory because I is already broken by the structure itself, and the detailed form of broken I-symmetry can often be designed. Also, two-dimensionality usually enhances the effects of electron correlations by reducing their kinetic energy. These two features of oxide interfaces produce many novel effects and functions that cannot be attained in bulk form. Given that the electromagnetic responses are a major source of the physical properties of solids, and new gauge structures often appear in correlated electronic systems, we put 'emergent electromagnetism' at the center of Fig. 1.

Hwang, H.Y.

2012-02-16T23:59:59.000Z

336

Single crystal oxide and oxide/oxide eutectic fibres for high temperature composites  

Science Journals Connector (OSTI)

The utilisation of fibre-reinforced metal, intermetallic and ceramic matrix composites (CMCs) in gas turbine engines offers the potential of improved fuel efficiency, higher operating temperature and greater thrust to weight ratio. The development of ceramic fibres with high strength, excellent strength retention at elevated temperatures and good creep resistance is essential to the successful implementation of composites in various high temperature components. Several single crystal oxide and oxide/oxide eutectic fibres have been developed to meet the demanding performance requirements. Recent progress made on developing these fibers will be discussed.

J.-M. Yang

2001-01-01T23:59:59.000Z

337

The catalytic oxidation of propane  

E-Print Network [OSTI]

THE CATALYTIC OXIDATION OP PROPANE A Thesis By Charles Frederick Sandersont * * June 1949 Approval as to style and content recommended: Head of the Department of Chemical Engineering THE CATALYTICi OXIDATTON OF PROPANE A Thesis By Charles... Frederick ;Sandersonit * June 1949 THE CATALYTIC OXIDATION OP PROPANE A Thesis Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

Sanderson, Charles Frederick

2013-10-04T23:59:59.000Z

338

Modifications of the surface properties of metals by oxide overlayers: 1, Oxidized zirconium deposited on the Pt(100) single crystal surface  

SciTech Connect (OSTI)

Metallic zirconium was deposited on a single crystal Pt(100) surface by thermal evaporation in UHV conditions. The deposit was oxidized by exposure to oxygen immediately after deposition. Oxidized zirconium was found to grow on the platinum ace by the layer-by-layer mechanism. The adsorption of carbon monoxide on the surface was studied as a function of the zirconium coverage. The results show that oxidized zirconium forms a chemically inert layer which blocks the adsorptive sites of the underlying platinum substrate. The properties of the free Pt surface were unaffected by the presence of the oxidized zirconium layer.

Bardi, U.; Ross, P.N.

1986-06-01T23:59:59.000Z

339

Conducting oxide formation and mechanical endurance of potential solid-oxide fuel cell interconnects in coal syngas environment  

SciTech Connect (OSTI)

The oxidation properties of potential SOFCs materials Crofer 22 APU, Ebrite and Haynes 230 exposed in coal syngas at 800 °C for 100 h were studied. The phases and surface morphology of the oxide scales were characterized by X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analysis (EDX). The mechanical endurance and electrical resistance of the conducting oxides were characterized by indentation and electrical impedance, respectively. It was found that the syngas exposure caused the alloys to form porous oxide scales, which increased the electrical resistant and decreased the mechanical stability. As for short-term exposure in syngas, neither carbide nor metal dusting was found in the scales of all samples.

Liu, Kejia; Luo, Junhang; Johnson, Christopher; Liu, Xingbo; Lang, J.; Mao, S.X.

2008-08-15T23:59:59.000Z

340

Molten Salt Oxidation of mixed wastes  

SciTech Connect (OSTI)

Molten Salt Oxidation (MSO) can be characterized as a simple noncombustion process; the basic concept is to introduce air and wastes into a bed of molten salt, oxidize the organic wastes in the molten salt, use the heat of oxidation to keep the salt molten and remove the salt for disposal or processing and recycling. The process has been developed through bench-scale and pilot-scale testing, with successful destruction demonstration of a wide variety of hazardous and mixed (radioactive and hazardous) wastes including chemical warfare agents, combustible solids, halogenated solvents, polychlorinated biphenyls, plutonium-contaminated solids, uranium-contaminated solvents and fission product-contaminated oil. The MSO destruction efficiency of the hazardous organic constituents in the wastes exceeds 99.9999%. Radioactive species, such as actinides and rare earth fission products, are retained in the salt bath. These elements can be recovered from the spent salt using conventional chemical processes, such as ion exchange, to render the salt as nonradioactive and nonhazardous. This paper reviews the principles and capabilities of MSO, previous mixed waste studies, and a new US Department of Energy program to demonstrate the process for the treatment of mixed wastes.

Gay, R.L.; Navratil, J.D.; Newman, C. [Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.

1993-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
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341

In situ reduction and oxidation of nickel from solid oxide fuel cells in a Titan ETEM  

E-Print Network [OSTI]

In situ reduction and oxidation of nickel from solid oxide fuel cells in a Titan ETEM A. Faes1. C. Singhal, K. Kendall, High Temperature Solid Oxide Fuel Cell - Fundamentals, Design, Denmark antonin.faes@epfl.ch Keywords: In situ ETEM, nickel oxide, reduction, RedOx, SOFC Solid Oxide Fuel

Dunin-Borkowski, Rafal E.

342

Transparent conducting oxides and production thereof  

SciTech Connect (OSTI)

Transparent conducting oxides and production thereof are disclosed. An exemplary method of producing a transparent conducting oxide (TCO) material may comprise: providing a TCO target doped with either a high-permittivity oxide or a low-permittivity oxide in a process chamber. The method may also comprise depositing a metal oxide on the target in the process chamber to form a thin film having enhanced optical properties without substantially decreasing electrical quality.

Gessert, Timothy A.; Yoshida, Yuki; Coutts, Timothy J.

2014-06-10T23:59:59.000Z

343

Transparent conducting oxides and production thereof  

SciTech Connect (OSTI)

Transparent conducting oxides and production thereof are disclosed. An exemplary method of producing a transparent conducting oxide (TCO) material may comprise: providing a TCO target (110) doped with either a high-permittivity oxide or a low-permittivity oxide in a process chamber (100). The method may also comprise depositing a metal oxide on the target (110) to form a thin film having enhanced optical properties without substantially decreasing electrical quality.

Gessert, Timothy A; Yoshida, Yuki; Coutts, Timothy J

2014-05-27T23:59:59.000Z

344

Nitric-phosphoric acid oxidation of organic waste materials  

SciTech Connect (OSTI)

A wet chemical oxidation technology has been developed to address issues facing defense-related facilities, private industry, and small-volume generators such as university and medical laboratories. Initially tested to destroy and decontaminate a heterogenous mixture of radioactive-contaminated solid waste, the technology can also remediate other hazardous waste forms. The process, unique to Savannah River, offers a valuable alternative to incineration and other high-temperature or high-pressure oxidation processes. The process uses nitric acid in phosphoric acid; phosphoric acid allows nitric acid to be retained in solution well above its normal boiling point. The reaction converts organics to carbon dioxide and water, and generates NO{sub x} vapors which can be recycled using air and water. Oxidation is complete in one to three hours. In previous studies, many organic compounds were completely oxidized, within experimental error, at atmospheric pressure below 180{degrees}C; more stable compounds were decomposed at 200{degrees}C and 170 kPa. Recent studies have evaluated processing parameters and potential throughputs for three primary compounds: EDTA, polyethylene, and cellulose. The study of polyvinylchloride oxidation is incomplete at this time.

Pierce, R.A.; Smith, J.R.

1995-11-01T23:59:59.000Z

345

Oxidants, Antioxidants and Cell Signaling  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Oxidants, Antioxidants and Cell Signaling Oxidants, Antioxidants and Cell Signaling Speaker(s): Chandan K. Sen Date: February 17, 1998 - 12:00pm Location: 90-3148 Seminar Host/Point of Contact: Richard Sextro Reactive oxygen species represent a common mediator of environmental stress such as during physical exercise, ozone exposure, UV radiation and xenobiotic (pollutant) metabolism. Antioxidant defense systems protect against the ravages of such reactive species. In contrast to the conventional idea that reactive oxygen is mostly a trigger for oxidative damage of biological structures, now we know that low physiologically relevant concentration of reactive oxygen species can regulate a variety of key molecular mechanisms that may be linked with important processes such as immune response, cell-cell adhesion, cell proliferation, inflammation,

346

Tin clustering and precipitation in the oxide during autoclave corrosion of Zircaloy-2  

Science Journals Connector (OSTI)

Abstract Atom probe tomography has been used to study the evolution of tin distribution during the corrosion process in Zircaloy-2. From being completely soluble in the Zr metal matrix, some clustering is evident already in the newly formed oxide close to the metal-oxide interface. Analysis of thicker oxides a few hundred nanometers away from the interface reveals fully developed precipitates of metallic Sn particles of up to 20 nm in size. Although the precipitates contain significant amounts of Zr, it is concluded that they are in the process of being depleted in Zr, which is limited only by the slow diffusion in the oxide scale. The findings are interpreted as being a result of the nobility of the Sn yielding a strong driving force to remain in a metallic state after incorporation in the barrier oxide layer. As Sn occupies substitutional sites in the ZrO2 lattice it is oxidized to a 4+ state when incorporated into the oxide, and in order to remain metallic it must nucleate into precipitates within the inner part of the oxide scale before being re-oxidized to 2+ and eventually to 4+ when the oxygen activity is sufficiently high in the outer parts of the oxide.

G. Sundell; M. Thuvander; H.-O. Andrén

2014-01-01T23:59:59.000Z

347

Suitability of Metallic Materials for Interconnects in Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

FeCr model alloys with variation of chromium content, reactive element addition and spinel forming elements were studied in respect to oxidation resistance at 800°C. Additionally, in-situ studies were carried ...

W. J. Quadakkers; J. Piron-Abellan…

2002-01-01T23:59:59.000Z

348

Aromatic-radical oxidation chemistry  

SciTech Connect (OSTI)

The research effort has focussed on discovering an explanation for the anomalously high CO{sub 2} concentrations observed early in the reaction sequence of the oxidation of cyclopentadiene. To explain this observation, a number of plausible mechanisms have been developed which now await experimental verification. One experimental technique for verifying mechanisms is to probe the reacting system by perturbing the radical concentrations. Two forms of chemical perturbation of the oxidation of cyclopentadiene were begun during this past year--the addition of NO{sub 2} and CO to the reacting mixture.

Glassman, I.; Brezinsky, K. [Princeton Univ., NJ (United States)

1993-12-01T23:59:59.000Z

349

Solid oxide fuel cell generator  

DOE Patents [OSTI]

A solid oxide fuel cell generator has a pair of spaced apart tubesheets in a housing. At least two intermediate barrier walls are between the tubesheets and define a generator chamber between two intermediate buffer chambers. An array of fuel cells have tubes with open ends engaging the tubesheets. Tubular, axially elongated electrochemical cells are supported on the tubes in the generator chamber. Fuel gas and oxidant gas are preheated in the intermediate chambers by the gases flowing on the other side of the tubes. Gas leakage around the tubes through the tubesheets is permitted. The buffer chambers reentrain the leaked fuel gas for reintroduction to the generator chamber.

Draper, Robert (Churchill Boro, PA); George, Raymond A. (Pittsburgh, PA); Shockling, Larry A. (Plum Borough, PA)

1993-01-01T23:59:59.000Z

350

Liquid-phase oxidation of components of compression process gasoline  

SciTech Connect (OSTI)

This report investigated the oxidation of hydrocarbons of various classes, the principal components of straight-run gasoline, under conditions similar to those used for industrial production of carboxylic acids at the Erevan Petroleum Refinery ''Nairit''. The study was carried out in the temperature range from 155 to 195/sup 0/C at a pressure of 5 MPa on an installation whose scheme was described previously. Normal paraffinic C/sub 5/-C/sub 8/ hydrocarbons, isoparaffinic hydrocarbons such as isopentane and isooctane (2,2,4-trimethylpentane), as well as cyclohexane were subjected to oxidation. The effluent gases were analyzed chromatographically for CO, CO/sub 2/ and hydrocarbon content, the oxidate was analyzed chemically for a total content of acids and chromatographically for its content of formic, acetic, propionic and butyric acids. This study also determined the content of acetone and water (chromatographically) and dicarboxylic acids (chemically).

Dayan, V.M.; Astratsatryan, S.A.; Kushina, I.D.; Pyzh, M.I.; Pazderskii, Y.A.; Bryukhovetskii, V.A.; Levush, S.S.

1982-06-01T23:59:59.000Z

351

Improvement in corrosion resistance of micro arc oxidation coating formed on AZ91D magnesium alloy via applying a nano-crystalline sol–gel layer  

Science Journals Connector (OSTI)

Although magnesium is used in many industries, it is reactive and requires protection against aggressive environments. In this study, oxide coating was formed on AZ91D magnesium alloy using micro-arc oxidation (M...

M. Laleh; Farzad Kargar; A. Sabour Rouhaghdam

2011-08-01T23:59:59.000Z

352

Superior Nanoscale Passive Oxide Layers Synthesized Under Photon Irradiation for Environmental Protection  

SciTech Connect (OSTI)

We report on synthesis and functional properties of ultra-thin oxide layers synthesized on metal surfaces by room temperature photon irradiation. We show that the impedance of a passive aluminum oxide film synthesized under ultraviolet photon irradiation is an order of magnitude larger than that of native oxide in a 0.5 M NaCl solution. Further, the structure and impedance of existing native oxide layers can be dramatically improved by minutes-long exposure to photon-irradiation. Depth profiling studies with X-ray photoelectron spectroscopy shows that chlorine uptake in UV-synthesized oxides, compared to that of native oxides, is reduced which can contribute to the improvement in corrosion resistance. The results are of significance to synthesis of ultra-thin passive layers on metal and alloy structures for environmental protection.

Chang, Chia-Lin; Engelhard, Mark H.; Ramanathan, Shriram

2008-06-30T23:59:59.000Z

353

Ultrafast Infrared Heating Laser Pulse-Induced Micellization Kinetics of Poly(ethylene oxide)-Poly(propylene oxide)-Poly(ethylene oxide) in  

E-Print Network [OSTI]

Ultrafast Infrared Heating Laser Pulse-Induced Micellization Kinetics of Poly(ethylene oxide)-Poly(propylene oxide)-Poly(ethylene oxide) in Water Xiaodong Ye, Yijie Lu, Shilin Liu,*, Guangzhao Zhang, and Chi Wu-induced micellization of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (Pluronic PE10300) triblock

Liu, Shilin

354

Using CrAIN Multilayer Coatings to Improve Oxidation Resistance...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Coatings to Improve Oxidation Resistance of Steel Interconnects for Solid Oxide Fuel Cell Stacks. Using CrAIN Multilayer Coatings to Improve Oxidation Resistance of Steel...

355

Computational Modeling of Graphene Oxide Exfoliation and Lithium Storage Characteristics.  

E-Print Network [OSTI]

??Graphene oxide is a two dimensional material obtained by adsorption of oxygen or oxygen-containing groups on graphene. Stacked layers of graphene oxide constitute graphite oxide.… (more)

Mortezaee, Reza

2013-01-01T23:59:59.000Z

356

Structural characterization of terrestrial microbial Mn oxides from Pinal Creek, AZ  

SciTech Connect (OSTI)

The microbial catalysis of Mn(II) oxidation is believed to be a dominant source of abundant sorption- and redox-active Mn oxides in marine, freshwater, and subsurface aquatic environments. In spite of their importance, environmental oxides of known biogenic origin have generally not been characterized in detail from a structural perspective. Hyporheic zone Mn oxide grain coatings at Pinal Creek, Arizona, a metals-contaminated stream, have been identified as being dominantly microbial in origin and are well studied from bulk chemistry and contaminant hydrology perspectives. This site thus presents an excellent opportunity to study the structures of terrestrial microbial Mn oxides in detail. XRD and EXAFS measurements performed in this study indicate that the hydrated Pinal Creek Mn oxide grain coatings are layer-type Mn oxides with dominantly hexagonal or pseudo-hexagonal layer symmetry. XRD and TEM measurements suggest the oxides to be nanoparticulate plates with average dimensions on the order of 11 nm thick x 35 nm diameter, but with individual particles exhibiting thickness as small as a single layer and sheets as wide as 500 nm. The hydrated oxides exhibit a 10-A basal-plane spacing and turbostratic disorder. EXAFS analyses suggest the oxides contain layer Mn(IV) site vacancy defects, and layer Mn(III) is inferred to be present, as deduced from Jahn-Teller distortion of the local structure. The physical geometry and structural details of the coatings suggest formation within microbial biofilms. The biogenic Mnoxides are stable with respect to transformation into thermodynamically more stable phases over a time scale of at least 5 months. The nanoparticulate layered structural motif, also observed in pure culture laboratory studies, appears to be characteristic of biogenic Mn oxides and may explain the common occurrence of this mineral habit in soils and sediments.

Bargar, John; Fuller, Christopher; Marcus, Matthew A.; Brearley, Adrian J.; Perez De la Rosa, M.; Webb, Samuel M.; Caldwell, Wendel A.

2008-03-19T23:59:59.000Z

357

Synthesis of monodisperse iron oxide nanocrystals by thermal decomposition of iron carboxylate salts{  

E-Print Network [OSTI]

's group12 recently published a study of c-Fe2O3 nanocrystals with different shapes. Iron acetylacetonateSynthesis of monodisperse iron oxide nanocrystals by thermal decomposition of iron carboxylate September 2004 Iron oxide (Fe3O4, magnetite) nanocrystals of 6 to 30 nm with narrow size distributions (s

Richards-Kortum, Rebecca

358

The effects of micro arc oxidation of gamma titanium aluminide surfaces on osteoblast adhesion and differentiation  

Science Journals Connector (OSTI)

The adhesion and proliferation of human fetal osteoblasts, hFOB 1.19, on micro arc oxidized (MAO) gamma titanium aluminide (?TiAl ... 6Al-4V disks to study the effect of micro arc oxidation and glass coverslips a...

Pricilla Santiago-Medina; Paul A. Sundaram…

2014-06-01T23:59:59.000Z

359

Solution Ionic Strength Engineering as a Generic Strategy to Coat Graphene Oxide (GO)  

E-Print Network [OSTI]

Solution Ionic Strength Engineering as a Generic Strategy to Coat Graphene Oxide (GO) on Various Functional Particles and Its Application in High-Performance Lithium- Sulfur (Li-S) Batteries Jiepeng Rong Angeles, California 90089, United States Graphene oxide (GO) synthesis GO used in this study was prepared

Zhou, Chongwu

360

Molecular dynamics simulations of the nano-scale room-temperature oxidation of aluminum single crystals  

E-Print Network [OSTI]

Molecular dynamics simulations of the nano-scale room-temperature oxidation of aluminum single Abstract The oxidation of aluminum single crystals is studied using molecular dynamics (MD) simulations with dynamic charge transfer between atoms. The simulations are performed on three aluminum low-index surfaces

Southern California, University of

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Cite this: RSC Advances, 2013, 3, Selective oxidation of 5-hydroxymethylfurfural to 2,5-  

E-Print Network [OSTI]

Cite this: RSC Advances, 2013, 3, 9942 Selective oxidation of 5-hydroxymethylfurfural to 2 and Franck Dumeignil*abeg The selective oxidation of 5-hydroxymethylfurfural (5-HMF) to 2,5-diformylfuran extensively studied for the production of 5-hydroxymethylfurfural (5-HMF), which is one of the key bio- based

Paris-Sud XI, Université de

362

Start | Author Index 742-1 Methylarsenate Sorption to Aluminum Oxide.  

E-Print Network [OSTI]

Start | Author Index 742-1 Methylarsenate Sorption to Aluminum Oxide. Wednesday, 8 October 2008: 1 is to investigate MMA and DMA sorption behavior to aluminum oxide employing a multi-scale approach. Macroscopic studies included: sorption isotherms, pH edges, sorption/desorption kinetics, and electrophoretic mobility

Sparks, Donald L.

363

Understanding the Chemistry of Uncommon Americium Oxidation States for Application to Actinide/Lanthanide Separations  

SciTech Connect (OSTI)

A spectroscopic study of the stability of Am(V) and Am(VI) produced by oxidizing Am(III) with sodium bismuthate is presented, varying the initial americium concentration, temperature and length of the oxidation was seen to have profound effects on the resultant solutions.

Leigh Martin; Bruce J. Mincher; Nicholas C. Schmitt

2007-09-01T23:59:59.000Z

364

Perovskite catalysts for oxidative coupling  

DOE Patents [OSTI]

Perovskites of the structure A.sub.2 B.sub.2 C.sub.3 O.sub.10 are useful as catalysts for the oxidative coupling of lower alkane to heavier hydrocarbons. A is alkali metal; B is lanthanide or lanthanum, cerium, neodymium, samarium, praseodymium, gadolinium or dysprosium; and C is titanium.

Campbell, Kenneth D. (Charleston, WV)

1991-01-01T23:59:59.000Z

365

Perovskite catalysts for oxidative coupling  

DOE Patents [OSTI]

Perovskites of the structure A[sub 2]B[sub 2]C[sub 3]O[sub 10] are useful as catalysts for the oxidative coupling of lower alkane to heavier hydrocarbons. A is alkali metal; B is lanthanide or lanthanum, cerium, neodymium, samarium, praseodymium, gadolinium or dysprosium; and C is titanium.

Campbell, K.D.

1991-06-25T23:59:59.000Z

366

Solid oxide fuel cell generator  

DOE Patents [OSTI]

A solid oxide fuel cell generator has a plenum containing at least two rows of spaced apart, annular, axially elongated fuel cells. An electrical conductor extending between adjacent rows of fuel cells connects the fuel cells of one row in parallel with each other and in series with the fuel cells of the adjacent row. 5 figures.

Di Croce, A.M.; Draper, R.

1993-11-02T23:59:59.000Z

367

Role of Nitrous Oxide in Ambulatory Anaesthesia  

Science Journals Connector (OSTI)

As the oldest anaesthetic still in routine use, the continued role of nitrous oxide is frequently questioned. There are a few well-defined situations in which nitrous oxide is contraindicated or undesirable; i...

Sarah Billingham; Ian Smith

2014-12-01T23:59:59.000Z

368

Complex oxides useful for thermoelectric energy conversion  

DOE Patents [OSTI]

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.

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

2012-07-17T23:59:59.000Z

369

Rare Iron Oxide in Ancient Chinese Pottery  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Rare Iron Oxide in Ancient Chinese Pottery Rare Iron Oxide in Ancient Chinese Pottery Print Friday, 26 September 2014 14:37 Jian ware (or Tenmoku) ceramic bowls, famous for their...

370

NANO - "Green" metal oxides ... | ornl.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

NANO - "Green" metal oxides ... Water and nano-sized particles isolated from trees, plants and algae are the ingredients of a new recipe for low-cost metal oxides that are widely...

371

Catalyst Additives to Enhance Mercury Oxidation and Capture  

SciTech Connect (OSTI)

Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. This report discusses initial results from fundamental investigations into the behavior of mercury species in the presence of SCR catalysts at Southern Research Institute. The testing was performed at Southern Research's Catalyst Test Facility, a bench-scale reactor capable of simulating gas-phase reactions occurring in coal-fired utility pollution-control equipment. Three different SCR catalysts are currently being studied in this project - honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts were manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Parametric testing was performed to investigate the contribution of flue-gas chemistry on mercury oxidation via SCR catalysts. Methods and procedures for experimental testing continue to be developed to produce the highest quality mercury-oxidation data. Most experiments so far have focused on testing the catalysts in a simulated Powder River Basin (PRB) flue-gas environment, which contains lower sulfur and chlorine than produced by other coals. Future work to characterize flue gas simulations typically derived from low and high sulfur bituminous coal will be performed in a stepwise manner, to avoid the constant interruptions in testing that occur when leaks in the system are generated during temperature transitions. Specifically, chlorine concentration vs. mercury oxidation graph will be developed for each catalyst. The contributions of temperature and later sulfur will be investigated after this is complete. Also, last quarter's tests showed a potential linear relationship between SO3 conversion and mercury oxidation. As a result, SO3 samples will be taken more frequently to investigate each catalyst's ability to selectively oxidize mercury.

Alex J. Berry; Thomas K. Gale

2005-09-30T23:59:59.000Z

372

Vapor phase modifiers for oxidative coupling  

DOE Patents [OSTI]

Volatilized metal compounds retard vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, Barbara K. (Charleston, WV)

1991-01-01T23:59:59.000Z

373

High quality oxide films on substrates  

DOE Patents [OSTI]

A method is described for providing an oxide film of a material on the surface of a substrate using a reactive deposition of the material onto the substrate surface in the presence of a solid or liquid layer of an oxidizing gas. The oxidizing gas is provided on the substrate surface in an amount sufficient to dissipate the latent heat of condensation occurring during deposition as well as creating a favorable oxidizing environment for the material. 4 figures.

Ruckman, M.W.; Strongin, M.; Gao, Y.L.

1994-02-01T23:59:59.000Z

374

Validation of a solid oxide fuel cell model  

Science Journals Connector (OSTI)

The need to study the performance of solid oxide fuel cells (SOFCs) has made mathematical modeling an essential tool for their design. Electrochemical modeling evaluates ohmic activation and concentration overpotentials that affect SOFC operation. A detailed cell model is developed for an SOFC and is validated with experimental data from the open literature.

Christina Charalampidou; Ioannis K. Kookos

2012-01-01T23:59:59.000Z

375

Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics  

E-Print Network [OSTI]

Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics Adrien Couet a to reduce hydrogen pickup during operation, and the associated cladding degradation. The present study focuses on precisely and accurately measuring hydrogen pickup fraction for a set of alloys to specifically

Motta, Arthur T.

376

High Temperature Oxidation of Iron-Chromium Alloys  

E-Print Network [OSTI]

and Peter H. Larsen for many good discussions during the work. #12;3 Abstract The high temperature oxidation: References: Abstract (max. 2000 char.): See page 3 Information Service Department Risø National Laboratory P of Southern Denmark. The majority of the work is based on studies performed at the SOFC group at the Materials

377

Oxidative Transformation of Triclosan and Chlorophene by  

E-Print Network [OSTI]

Oxidative Transformation of Triclosan and Chlorophene by Manganese Oxides H U I C H U N Z H A N G of Technology, Atlanta, Georgia 30332 The antibacterial agents triclosan (5-chloro-2-(2,4- dichlorophenoxy(-MnO2 andMnOOH)yielding MnII ions. Both the initial reaction rate and adsorption of triclosan to oxide

Huang, Ching-Hua

378

Nitrous oxide emissions from wastewater treatment processes  

Science Journals Connector (OSTI)

...specific ammonia oxidation rate. Symbols represent...Research Council (ARC) for funding this...correlated to its ammonia oxidation rate. 51 Arp, D...1146/annurev.micro.61.080706.093449...1146/annurev.micro.61.080706.093449...2004 Anaerobic oxidation of inorganic nitrogen...

2012-01-01T23:59:59.000Z

379

REVERSIBLE SOLID OXIDE CELLS Mogens Mogensen1  

E-Print Network [OSTI]

The reversibility of solid oxide fuel cells (SOFC), i.e. that they could also work in the solid oxide electrolyser1 REVERSIBLE SOLID OXIDE CELLS Mogens Mogensen1 , Søren Højgaard Jensen1,2 , Anne Hauch1,3 , Ib Chorkendorff2 and Torben Jacobsen3 1 Fuel Cell and Solid State Chemistry Department Risø National Laboratory

380

Solid Oxide Electrolysis Cells Performance and Durability  

E-Print Network [OSTI]

Title: Solid Oxide Electrolysis Cells ­ Performance and Durability Department: Fuel Cells and SolidSolid Oxide Electrolysis Cells ­ Performance and Durability Anne Hauch Risø-PhD-37(EN) Risø : Images from transmission electron microscopy investigation of the H2 electrode for the solid oxide cell

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Photo-oxides of Carcinogenic Hydrocarbons  

Science Journals Connector (OSTI)

... are involved in the biological action of carcinogenic hydrocarbons, we have attempted to isolate the photo-oxides of some of these hydrocarbons. Such ... -oxides of some of these hydrocarbons. Such photo-oxides would naturally be insoluble in water and hence would represent merely one stage in ...

J. W. COOK; R. MARTIN; E. M. F. ROE

1939-06-17T23:59:59.000Z

382

Dense high temperature ceramic oxide superconductors  

DOE Patents [OSTI]

Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.

Landingham, Richard L. (Livermore, CA)

1993-01-01T23:59:59.000Z

383

ORIGINAL ARTICLE Sulfur oxidizers dominate carbon fixation  

E-Print Network [OSTI]

). Methylotrophs and iron oxidizers were also active in plume waters and expressed key proteins for methane by bacteria (especially, alpha-, gamma- and epsilon-proteobacteria) that likely participate in the oxidationORIGINAL ARTICLE Sulfur oxidizers dominate carbon fixation at a biogeochemical hot spot in the dark

Hansell, Dennis

384

Nanotube Fabrication byNanotube Fabrication by Anodic Aluminum Oxide,Anodic Aluminum Oxide,  

E-Print Network [OSTI]

Nanotube Fabrication byNanotube Fabrication by Anodic Aluminum Oxide,Anodic Aluminum Oxide, Self-regulating phenomena in materials science: Self-assembly of nanopores during anodic oxidation of aluminum (AAO) Self combined anodic aluminum oxide (AAO) nanostructures with atomic layer deposition (ALD) to fabricate

Rubloff, Gary W.

385

Direct oxidation of hydrocarbons in a solid oxide fuel cell. I. Methane oxidation  

SciTech Connect (OSTI)

The performance of Cu cermets as anodes for the direct oxidation of CH{sub 4} in solid oxide fuel cells was examined. Mixtures of Cu and yttria-stabilized zirconia (YAZ) were found to give similar performance to Ni-YSZ cermets when H{sub 2} was used as the fuel, but did not deactivate in dry CH{sub 4}. While Cu-YSZ was essentially inert to methane, the addition of ceria to the anode gave rise to reasonable power densities and stable operation over a period of at least 3 days. Proof of direct oxidation of CH{sub 4} came from chemical analysis of the products leaving the cell. The major carbon-containing product was CO{sub 2}, with only traces of CO observed, and there was excellent agreement between the actual cell current and that predicted by the methane conversion. These results demonstrate that direct, electrocatalytic oxidation of dry methane is possible, with reasonable performance.

Park, S.; Craciun, R.; Vohs, J.M.; Gorte, R.J.

1999-10-01T23:59:59.000Z

386

Nitric oxide emissions from the high-temperature viscous boundary layers of hypersonic aircraft within the stratosphere  

SciTech Connect (OSTI)

The authors study the nitric oxide emission characteristics of supersonic aircraft resulting from heating of viscous boundary layers along the skin of the aircraft. Previous study has concentrated on nitric oxide emissions coming from combustion products from the scramjet engines. This work shows that above mach 8, emissions from viscous heating become a significant factor in total emission of nitric oxide. Above mach 16 it becomes the dominant source of emission.

Brooks, S.B.; Lewis, M.J.; Dickerson, R.R. [Univ. of Maryland, College Park, MD (United States)

1993-09-20T23:59:59.000Z

387

Perform Tests and Document Results and Analysis of Oxide Layer Effects and Comparisons  

SciTech Connect (OSTI)

During the initial feasibility test using actual used nuclear fuel (UNF) cladding in FY 2012, an incubation period of 30–45 minutes was observed in the initial dry chlorination. The cladding hull used in the test had been previously oxidized in a dry air oxidation pretreatment prior to removal of the fuel. The cause of this incubation period was attributed to the resistance to chlorination of an oxide layer imparted by the dry oxidation pretreatment on the cladding. Subsequently in 2013, researchers at the Korea Atomic Energy Institute (KAERI) reported on their chlorination study [R1] on ~9-gram samples of unirradiated ZirloTM cladding tubes that had been previously oxidized in air at 500oC for various time periods to impart oxide layers of varying thickness. In early 2014, discussions with Indefinite Delivery, Indefinite Quantity (IDIQ) contracted technical consultants from Westinghouse described their previous development (and patents) [R2] on methods of chemical washing to remove some or all of the hydrous oxide layer imparted on UNF cladding during irradiation in light water reactors (LWRs) . Thus, the Oak Ridge National Laboratory (ORNL) study, described herein, was planned to extend the KAERI study on the effects of anhydrous oxide layers, but on larger ~100-gram samples of unirradiated zirconium alloy cladding tubes, and to investigate the effects of various methods of chemical pretreatment prior to chlorination with 100% chlorine on the average reaction rates and Cl2 usage efficiencies.

Collins, E. D. [ORNL; DelCul, G. D. [ORNL; Spencer, B. B. [ORNL; Hunt, R. D. [ORNL; Ausmus, C. [ORNL

2014-08-30T23:59:59.000Z

388

Catalyst Additives to Enhance Mercury Oxidation and Capture  

SciTech Connect (OSTI)

Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. This report discusses initial results from fundamental investigations into the behavior of mercury species in the presence of SCR catalysts at Southern Research Institute. Three different SCR catalysts are being studied. These are honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts are manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Test methods and experimental procedures were developed for current and future testing. The methods and procedures equalize factors influencing mercury adsorption and oxidation (surface area, catalyst activity, and pore structure) that normally differ for each catalyst type. Initial testing was performed to determine the time necessary for each catalyst to reach surface-adsorption equilibrium. In addition, the fraction of Hg oxidized by each of the SCR catalyst types is being investigated, for a given amount of catalyst and flow rate of mercury and flue gas. The next major effort will be to examine the kinetics of mercury oxidation across the SCR catalysts with respect to changes in mercury concentration and with respect to HCl concentration. Hg-sorption equilibrium times will also be investigated with respect to ammonia concentration in the simulated flue gas.

Jared W. Cannon; Thomas K. Gale

2004-12-31T23:59:59.000Z

389

MOISTURE AND SURFACE AREA MEASUREMENTS OF PLUTONIUM-BEARING OXIDES  

SciTech Connect (OSTI)

To ensure safe storage, plutonium-bearing oxides are stabilized at 950 C for at least two hours in an oxidizing atmosphere. Stabilization conditions are expected to decompose organic impurities, convert metals to oxides, and result in moisture content below 0.5 wt%. During stabilization, the specific surface area is reduced, which minimizes readsorption of water onto the oxide surface. Plutonium oxides stabilized according to these criteria were sampled and analyzed to determine moisture content and surface area. In addition, samples were leached in water to identify water-soluble chloride impurity content. Results of these analyses for seven samples showed that the stabilization process produced low moisture materials (< 0.2 wt %) with low surface area ({le} 1 m{sup 2}/g). For relatively pure materials, the amount of water per unit surface area corresponded to 1.5 to 3.5 molecular layers of water. For materials with chloride content > 360 ppm, the calculated amount of water per unit surface area increased with chloride content, indicating hydration of hygroscopic salts present in the impure PuO{sub 2}-containing materials. The low moisture, low surface area materials in this study did not generate detectable hydrogen during storage of four or more years.

Crowder, M.; Duffey, J.; Livingston, R.; Scogin, J.; Kessinger, G.; Almond, P.

2009-09-28T23:59:59.000Z

390

Modification of epitaxial oxide films with ion implantation  

SciTech Connect (OSTI)

Ion implantation is used to modify the properties of oxide (YBCO and YSZ) thin films. Both superconducting and dielectric epitaxial oxide films, grown by laser ablation, are studied. The properties of the implanted oxide films are characterized by SIMS, XPS, DC resistivity and AC susceptibility measurements. By introducing reactive ions into superconducting oxide films, the conductivity of the material is inhibited possibly due to the interaction of the implanted ions with oxygen originally bound to the copper atoms. Al, Si, Ag and Ca ions are implanted into epitaxial YBCO films with injection energies ranging from 50--100 KeV and doses ranging from 1 {times} 10{sup 15}--1 {times} 10{sup 16}/cm{sup 2}. XPS analysis shows that the implanted Si ions form SiO{sub x}. The inhibition method has been applied to the fabrication of superconducting electronic devices, such as SQUIDs. Dielectric oxide films are doped by the implantation of conductive and nonconductive ions. YSZ films are doped with Ag and Si ions and the ions are found to increase the conductivity.

Hong, S.H.; Miller, J.R.; Ma, Q.Y.; Yang, E.S. [Columbia Univ., New York, NY (United States). Dept. of Electrical Engineering; Fenner, D.B. [AFR Inc., East Hartford, CT (United States); Yang, C.Y. [Santa Clara Univ., CA (United States). Microelectronics Lab.; Budnick, J.I. [Univ. of Connecticut, Storrs, CT (United States). Dept. of Physics

1996-11-01T23:59:59.000Z

391

Scanning Transmission Electron Microscopy Investigations of Complex Oxides  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Scanning Transmission Electron Microscopy Investigations of Complex Oxides Scanning Transmission Electron Microscopy Investigations of Complex Oxides Monday, May 23, 2011 - 3:30pm SSRL Conference room 137-322 Professor Tom Vogt, NanoCenter & Department of Chemistry, University of South Carolina High-Angle-Annular-Dark-Field/Scanning Transmission Electron Microscopy (HAADF/STEM) is a technique uniquely suited for detailed studies of the structure and composition of complex oxides. The HAADF detector collects electrons which have interact inelastically with the potentials of the atoms in the specimen and therefore resembles the better known Z2 (Z is atomic number) Rutherford scattering. One class of important catalysts consists of bronzes based on pentagonal {Mo6O21} building units; these include Mo5O14 and Mo17O47. In the last 20 years, new materials doped with

392

Effect of chromium oxide as active site over TiO2-PILC for selective catalytic oxidation of NO  

Science Journals Connector (OSTI)

Abstract This study introduced TiO2-pillared clays (TiO2-PILC) as a support for the catalytic oxidation of NO and analyzed the performance of chromium oxides as the active site of the oxidation process. Cr-based catalysts were prepared by a wet impregnation method. It was found that the 10 wt.% chromium doping on the support achieved the best catalytic activity. At 350°C, the NO conversion was 61% under conditions of GHSV = 23600 hr?1. The BET data showed that the support particles had a mesoporous structure. H2-TPR showed that Cr(10)TiP (10 wt.% Cr doping on TiO2-PILC) clearly exhibited a smooth single peak. EPR and XPS were used to elucidate the oxidation process. During the NO + O2 adsorption, the intensity of evolution of superoxide ions (O2?) increased. The content of Cr3+ on the surface of the used catalyst was 40.37%, but when the used catalyst continued adsorbing NO, the Cr3+ increased to 50.28%. Additionally, O?/O? increased markedly through the oxidation process. The NO conversion decreased when SO2 was added into the system, but when the SO2 was removed, the catalytic activity recovered almost up to the initial level. FT-IR spectra did not show a distinct characteristic peak of SO42?.

Jingxin Zhang; Shule Zhang; Wei Cai; Qin Zhong

2013-01-01T23:59:59.000Z

393

Fundamentals of Mercury Oxidation in Flue Gas  

SciTech Connect (OSTI)

The objective of this project is to understand the importance of and the contribution of gas-phase and solid-phase coal constituents in the mercury oxidation reactions. The project involves both experimental and modeling efforts. The team is comprised of the University of Utah, Reaction Engineering International, and the University of Connecticut. The objective is to determine the experimental parameters of importance in the homogeneous and heterogeneous oxidation reactions; validate models; and, improve existing models. Parameters to be studied include HCl, NO{sub x}, and SO{sub 2} concentrations, ash constituents, and temperature. This report summarizes Year 2 results for the experimental and modeling tasks. Experiments in the mercury reactor are underway and interesting results suggested that a more comprehensive look at catalyzed surface reactions was needed. Therefore, much of the work has focused on the heterogeneous reactions. In addition, various chemical kinetic models have been explored in an attempt to explain some discrepancies between this modeling effort and others.

JoAnn S. Lighty; Geoffrey Silcox; Andrew Fry; Constance Senior; Joseph Helble; Balaji Krishnakumar

2005-08-01T23:59:59.000Z

394

Nitrogen Oxides Emission Control Options  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nitrogen Nitrogen Oxides Emission Control Options for Coal-Fired Electric Utility Boilers Ravi K. Srivastava and Robert E. Hall U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Air Pollution Prevention and Control Division, Research Triangle Park, NC Sikander Khan and Kevin Culligan U.S. Environmental Protection Agency, Office of Air and Radiation, Clean Air Markets Division, Washington, DC Bruce W. Lani U.S. Department of Energy, National Energy Technology Laboratory, Environmental Projects Division, Pittsburgh, PA ABSTRACT Recent regulations have required reductions in emissions of nitrogen oxides (NO x ) from electric utility boilers. To comply with these regulatory requirements, it is increas- ingly important to implement state-of-the-art NO x con- trol technologies on coal-fired utility boilers. This paper reviews NO x control

395

Semiconductive Properties of Uranium Oxides  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

SEMICONDUCTIVE PROPERTIES OF URANIUM OXIDES SEMICONDUCTIVE PROPERTIES OF URANIUM OXIDES Thomas Meek Materials Science Engineering Department University of Tennessee Knoxville, TN 37931 Michael Hu and M. Jonathan Haire Chemical Technology Division Oak Ridge National Laboratory * Oak Ridge, Tennessee 37831-6179 August 2000 For the Waste Management 2001 Symposium Tucson, Arizona February 25-March 1, 2001 The submitted manuscript has been authored by a contractor of the U.S. Government under contract DE-AC05-00OR22725. Accordingly, the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes. _________________________ * Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Department of Energy

396

Classification of oxide glasses: A polarizability approach  

SciTech Connect (OSTI)

A classification of binary oxide glasses has been proposed taking into account the values obtained on their refractive index-based oxide ion polarizability {alpha}{sub O2-}(n{sub 0}), optical basicity {lambda}(n{sub 0}), metallization criterion M(n{sub 0}), interaction parameter A(n{sub 0}), and ion's effective charges as well as O1s and metal binding energies determined by XPS. Four groups of oxide glasses have been established: glasses formed by two glass-forming acidic oxides; glasses formed by glass-forming acidic oxide and modifier's basic oxide; glasses formed by glass-forming acidic and conditional glass-forming basic oxide; glasses formed by two basic oxides. The role of electronic ion polarizability in chemical bonding of oxide glasses has been also estimated. Good agreement has been found with the previous results concerning classification of simple oxides. The results obtained probably provide good basis for prediction of type of bonding in oxide glasses on the basis of refractive index as well as for prediction of new nonlinear optical materials.

Dimitrov, Vesselin [Department of Silicate Technology, University of Chemical Technology and Metallurgy, 8 Kl. Ohridski Blvd., Sofia 1756 (Bulgaria); Komatsu, Takayuki [Department of Chemistry, The Nagaoka University of Technology, 1603-1 Kamitomioka-cho, Nagaoka-shi, Niigata-ken 940-2188 (Japan)]. E-mail: komatsu@chem.nagaokaut.ac.jp

2005-03-15T23:59:59.000Z

397

Kinetics of Diesel Nanoparticle Oxidation  

Science Journals Connector (OSTI)

The oxidation rates in air of diesel nanoparticles sampled directly from the exhaust stream of a medium-duty diesel engine were measured over the temperature range of 800?1140 °C using online aerosol techniques. ... Particulate emission from diesel engines is currently a topic of great concern from both pollution and public health standpoints. ... In addition, the fundamental carbon-to-hydrogen ratio may be different in diesel particles as compared to the commonly used surrogates (15). ...

Kelly J. Higgins; Heejung Jung; David B. Kittelson; Jeffrey T. Roberts; Michael R. Zachariah

2003-03-25T23:59:59.000Z

398

Atmospheric Oxidation of Coal at Moderate Temperatures. Effect of Oxidation on the Carbonizing Properties of Representative Coking Coals.  

Science Journals Connector (OSTI)

Atmospheric Oxidation of Coal at Moderate Temperatures. ... Effect of Oxidation on the Carbonizing Properties of Representative Coking Coals. ...

L Schmidt; J Elder; J Davis

1940-01-01T23:59:59.000Z

399

Nanowire-based All Oxide Solar Cells  

SciTech Connect (OSTI)

We present an all-oxide solar cell fabricated from vertically oriented zinc oxide nanowires and cuprous oxide nanoparticles. Our solar cell consists of vertically oriented n-type zinc oxide nanowires, surrounded by a film constructed from p-type cuprous oxide nanoparticles. Our solution-based synthesis of inexpensive and environmentally benign oxide materials in a solar cell would allow for the facile production of large-scale photovoltaic devices. We found that the solar cell performance is enhanced with the addition of an intermediate oxide insulating layer between the nanowires and the nanoparticles. This observation of the important dependence of the shunt resistance on the photovoltaic performance is widely applicable to any nanowire solar cell constructed with the nanowire array in direct contact with one electrode.

Yang*, Benjamin D. Yuhas and Peidong; Yang, Peidong

2008-12-07T23:59:59.000Z

400

Interfacial electrochemistry of pyrite oxidation and flotation. 1: Effect of borate on pyrite surface oxidation  

SciTech Connect (OSTI)

The interfacial chemistry of pyrite is of great industrial importance in complex sulfide ore flotation, coal desulfurization, acid mine drainage mitigation, and conversion of solar energy to electrical or chemical energy. Sodium tetraborate (Na{sub 2}B{sub 4}O{sub 7}) has been widely used as an electrolyte and pH buffer in studying the interfacial electrochemistry of sulfide minerals in relation to sulfide mineral flotation. In all the previous studies published so far, borate was regarded as an inert electrolyte/pH buffer, and its reactions with the sulfide minerals were completely overlooked. In this first part of this series papers, the complicating effects of borate on the interfacial electrochemistry of pyrite have been studied. In the borate solutions, the surface oxidation of pyrite is strongly enhanced. The first and rate-determining step of the reaction between borate and pyrite has been shown to be the following irreversible reaction: FeS{sub 2} + B(OH){sub 4}{sup {minus}} {yields} FeS{sub 2} {hor_ellipsis} [B(OH){sub 4}]{sub ads} + e. This reaction appears in the voltammogram as an anodic oxidation peak at potentials of more than 0.4 V lower than the commencement of pyrite oxidation in sodium perchlorate or nitrate electrolyte solutions. As the borate concentration increases, the peak current increases linearly, while the peak potential shifts positively at 240 mV per decade. On a rotating-disc electrode, the peak becomes a plateau. The limiting current density is a linear function of the square root of the rotation speed at relatively low rotation speeds. The Tafel slope is close to 240 mV per decade and is independent of the rotation speed and borate concentration. The results indicate that charge transfer coefficient is 0.25.

Wang, X.H. [Univ. of Kentucky, Lexington, KY (United States)] [Univ. of Kentucky, Lexington, KY (United States)

1996-03-25T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Size-selected Pt Nanoparticles Synthesized via Micelle Encapsulation: Effect of Pretreatment and Oxidation State on the Activity for Methanol Decomposition and  

E-Print Network [OSTI]

and Oxidation State on the Activity for Methanol Decomposition and Oxidation Jason R. Croya , S. Mostafaa,b , H-synthesized Pt nanoparticles supported on ZrO2 was studied for methanol decomposition and oxidation reactions. An O2-pretreatment is observed to be effective for producing clean, stable, and active nanoparticles

Kik, Pieter

402

Identification and molecular characterization of novel genomic targets in oxidant-induced vascular injury  

E-Print Network [OSTI]

Gene expression was examined in vascular smooth muscle cells to study the complex interaction between oxidative injury and the pathogenesis of vascular disease. Extensive vascular remodeling coupled to increased production of 8-epi-PGF2�± nuclear...

Partridge, Charles Randal

2007-04-25T23:59:59.000Z

403

Nitric oxide inhibits the production of soluble endothelin converting enzyme-1  

Science Journals Connector (OSTI)

This study examined the effect of nitric oxide on the production of soluble ECE-1. Activity of ECE-1 in media was measured using a quenched fluorescent substrate assay, and expressed as a percentage of control...

Sanjaya Kuruppu; Niwanthi W. Rajapakse…

2014-11-01T23:59:59.000Z

404

Conjugated linoleic acid reduces lipid oxidation in irradiated, cooked ground beef patties  

E-Print Network [OSTI]

This study was conducted to examine the antioxidative effect of conjugated linoleic acid (CLA) in irradiated, cooked ground beef patties. The hypothesis was that CLA would be retained during irradiation and would reduce lipid oxidation...

Chae, Sung Hee

2007-09-17T23:59:59.000Z

405

Proline metabolism increases katG expression and oxidative stress resistance in Escherichia coli  

Science Journals Connector (OSTI)

...delta1-pyrroline-5-carboxylate (P5C) dehydrogenase domains in a single polypeptide. Previous studies have suggested that aside from providing energy, proline metabolism influences oxidative stress resistance in different organisms. To explore this potential role and the...

Lu Zhang; James R. Alfano; Donald F. Becker

2014-11-10T23:59:59.000Z

406

Two-photon nitric oxide laser-induced fluorescence measurements in a diesel engine  

Science Journals Connector (OSTI)

A two-photon nitric oxide (NO) laser-induced fluorescence (LIF) technique was developed and applied to study in-cylinder diesel combustion. The technique prevents many problems...

Martin, Glen C; Mueller, Charles J; Lee, Chia-Fon F

2006-01-01T23:59:59.000Z

407

Comparative Life-Cycle Assessment of Residential Heating Systems, Focused on Solid Oxide Fuel Cells  

Science Journals Connector (OSTI)

This study aims to analyze a Solid Oxide Fuel Cell (SOFC) for residential heating applications by...producer, the user as an individual and the user...intended as the heating demand of a building, applied by defa...

Alba Cánovas; Rainer Zah; Santiago Gassó

2013-01-01T23:59:59.000Z

408

Amino acids, polyamines, and nitric oxide synthesis in the ovine conceptus  

E-Print Network [OSTI]

The objective of this study was to determine concentrations of amino acids and polyamines as well as nitric oxide (NO) and polyamine synthesis in the ovine conceptus (embryo/fetal and associated placental membrane). Ewes were hysterectomized...

Kwon, Hyuk Jung

2005-08-29T23:59:59.000Z

409

On the Acid-Base Mechanism for Ruthenium Water Oxidation Catalysts  

E-Print Network [OSTI]

We present a detailed theoretical study of the pathway for water oxidation in synthetic ruthenium-based catalysts. As a first step, we consider a recently discovered single center catalyst, where experimental observations ...

Wang, Lee-Ping

410

Effects of Depleted Uranium on Oxidative Stress, Detoxification, and Defence Parameters of Zebrafish Danio rerio  

Science Journals Connector (OSTI)

In this study, we investigated the effects of depleted uranium (DU), the by-product of nuclear enrichment of uranium, on several parameters related to oxidative stress...Danio rerio. Several parameters were recor...

Beatrice Gagnaire; Isabelle Cavalie…

2013-01-01T23:59:59.000Z

411

Hydrogen Oxidation and Evolution Reaction Kinetics on Platinum: Acid vs Alkaline Electrolytes  

E-Print Network [OSTI]

The kinetics of the hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) on polycrystalline platinum [Pt(pc)] and high surface area carbon-supported platinum nanoparticles (Pt/C) were studied in 0.1 M ...

Sheng, Wenchao

412

Calculation of the emission of nitrogen oxides in electric resistance heating furnaces  

Science Journals Connector (OSTI)

The present paper is devoted to the least studied topic in the field of use of modern electric heating equipment, namely, pollution of the atmosphere by nitrogen oxides and reduction of the intensity of this e...

A. V. Aksenov; V. A. Belyakov; Z. G. Sadykova

1998-02-01T23:59:59.000Z

413

Quantum conductance of zigzag graphene oxide nanoribbons  

SciTech Connect (OSTI)

The electronic properties of zigzag graphene oxide nanoribbons (ZGOR) are presented. The results show interesting behaviors which are considerably different from the properties of the perfect graphene nanoribbons (GNRs). The theoretical methods include a Huckel-tight binding approach, a Green's function methodology, and the Landauer formalism. The presence of oxygen on the edge results in band bending, a noticeable change in density of states and thus the conductance. Consequently, the occupation in the valence bands increase for the next neighboring carbon atom in the unit cell. Conductance drops in both the conduction and valence band regions are due to the reduction of allowed k modes resulting from band bending. The asymmetry of the energy band structure of the ZGOR is due to the energy differences of the atoms. The inclusion of a foreign atom's orbital energies changes the dispersion relation of the eigenvalues in energy space. These novel characteristics are important and valuable in the study of quantum transport of GNRs.

Kan, Zhe; Nelson, Christopher; Khatun, Mahfuza, E-mail: mkhatun@bsu.edu [Department of Physics and Astronomy, Center for Computational Nanoscience, Ball State University, Muncie, Indiana 47306 (United States)

2014-04-21T23:59:59.000Z

414

Ultrafiltration evaluation with depleted uranium oxide  

SciTech Connect (OSTI)

Scientists at the Los Alamos National Laboratory Plutonium Facility are using electrodissolution in neutral to alkaline solutions to decontaminate oralloy parts that have surface plutonium contamination. Ultrafiltration of the electrolyte stream removes precipitate so that the electrolyte stream to the decontamination fixture is precipitate free. This report describes small-scale laboratory ultrafiltration experiments that the authors performed to determine conditions necessary for full-scale operation of an ultrafiltration module. Performance was similar to what they observed in the ferric hydroxide system. At 12 psi transmembrane pressure, a shear rate of 12,000 sec{sup {minus}1} was sufficient to sustain membrane permeability. Ultrafiltration of uranium(VI) oxide appears to occur as easily as ultrafiltration of ferric hydroxide. Considering the success reported in this study, the authors plan to add ultrafiltration to the next decontamination system for oralloy parts.

Weisbrod, K.R.; Schake, A.R.; Morgan, A.N.; Purdy, G.M.; Martinez, H.E.; Nelson, T.O.

1998-03-01T23:59:59.000Z

415

Fusion Techniques for the Oxidation of Refractory Actinide Oxides  

SciTech Connect (OSTI)

Small-scale experiments were performed to demonstrate the feasibility of fusing refractory actinide oxides with a series of materials commonly used to decompose minerals, glasses, and other refractories as a pretreatment to dissolution and subsequent recovery operations. In these experiments, 1-2 g of plutonium or neptunium oxide (PuO2 or NpO2) were calcined at 900 degrees Celsius, mixed and heated with the fusing reagent(s), and dissolved. For refractory PuO2, the most effective material tested was a lithium carbonate (Li2CO3)/sodium tetraborate (Na2B4O7) mixture which aided in the recovery of 90 percent of the plutonium. The fused product was identified as a lithium plutonate (Li3PuO4) by x-ray diffraction. The use of a Li2CO3/Na2B4O7 mixture to solubilize high-fired NpO2 was not as effective as demonstrated for refractory PuO2. In a small-scale experiment, 25 percent of the NpO2 was oxidized to a neptunium (VI) species that dissolved in nitric acid. The remaining neptunium was then easily recovered from the residue by fusing with sodium peroxide (Na2O2). Approximately 70 percent of the neptunium dissolved in water to yield a basic solution of neptunium (VII). The remainder was recovered as a neptunium (VI) solution by dissolving the residue in 8M nitric acid. In subsequent experiments with Na2O2, the ratio of neptunium (VII) to (VI) was shown to be a function of the fusion temperature, with higher temperatures (greater than approximately 400 degrees C) favoring the formation of neptunium (VII). The fusion of an actual plutonium-containing residue with Na2O2 and subsequent dissolution was performed to demonstrate the feasibility of a pretreatment process on a larger scale. Sodium peroxide was chosen due to the potential of achieving higher actinide recoveries from refractory materials. In this experiment, nominally 10 g of a graphite-containing residue generated during plutonium casting operations was initially calcined to remove the graphite. Removal of combustible material prior to a large-scale fusion with Na2O2 is needed due to the large amount of heat liberated during oxidation. Two successive fusions using the residue from the calcination and the residue generated from the initial dissolution allowed recovery of 98 percent of the plutonium. The fusion of the residue following the first dissolution was performed at a higher temperature (600 degrees Celsius versus 450 degrees Celsius during the first fusion). The ability to recover most of the remaining plutonium from the residue suggest the oxidation efficiency of the Na2O2 fusion improves with higher temperatures similar to results observed with NpO2 fusion.

Rudisill, T.S.

1999-04-15T23:59:59.000Z

416

Catalyst Additives to Enhance Mercury Oxidation and Capture  

SciTech Connect (OSTI)

Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. This report discusses initial results from fundamental investigations into the behavior of mercury species in the presence of SCR catalysts at Southern Research Institute. The testing was performed at Southern Research's Catalyst Test Facility, a bench-scale reactor capable of simulating gas-phase reactions occurring in coal-fired utility pollution-control equipment. Three different SCR catalysts are currently being studied in this project--honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts were manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Parametric testing was performed to investigate the contribution of flue-gas chemistry on mercury oxidation via SCR catalysts. Methods and procedures for experimental testing continue to be developed to produce the highest quality mercury-oxidation data. During this past quarter, it was discovered that long periods (12 - 24 hours) are required to equilibrate the catalysts in the system. In addition, after the system has been equilibrated, operational changes to temperature, gas concentration, or flow rate shifts the equilibrium, and steady-state must be reestablished, which can require as much as twelve additional hours per condition change. In the last quarter of testing, it was shown that the inclusion of ammonia had a strong effect on the oxidation of mercury by SCR catalysts, both in the short-term (a transitional period of elemental and oxidized mercury off gassing) and the long-term (less steady-state mercury oxidation). All experiments so far have focused on testing the catalysts in a simulated Powder River Basin (PRB) flue-gas environment, which contains lower sulfur and chlorine than produced by other coals. In the next quarter, parametric testing will be expanded to include flue gases simulating power plants burning Midwestern and Eastern coals, which are higher in sulfur and chlorine. Also, the isolation of such gases as hydrogen chloride (HCl), ammonia (NH{sub 3}), and sulfur trioxide (SO{sub 3}) will be investigated. All of these efforts will be used to examine the kinetics of mercury oxidation across the SCR catalysts with respect to flue gas composition, temperature, and flow rate.

Jared W. Cannon; Thomas K. Gale

2005-06-30T23:59:59.000Z

417

DISSOLUTION OF NEPTUNIUM OXIDE RESIDUES  

SciTech Connect (OSTI)

This report describes the development of a dissolution flowsheet for neptunium (Np) oxide (NpO{sub 2}) residues (i.e., various NpO{sub 2} sources, HB-Line glovebox sweepings, and Savannah River National Laboratory (SRNL) thermogravimetric analysis samples). Samples of each type of materials proposed for processing were dissolved in a closed laboratory apparatus and the rate and total quantity of off-gas were measured. Samples of the off-gas were also analyzed. The quantity and type of solids remaining (when visible) were determined after post-dissolution filtration of the solution. Recommended conditions for dissolution of the NpO{sub 2} residues are: Solution Matrix and Loading: {approx}50 g Np/L (750 g Np in 15 L of dissolver solution), using 8 M nitric acid (HNO{sub 3}), 0.025 M potassium fluoride (KF) at greater than 100 C for at least 3 hours. Off-gas: Analysis of the off-gas indicated nitric oxide (NO), nitrogen dioxide (NO{sub 2}) and nitrous oxide (N{sub 2}O) as the only identified components. No hydrogen (H{sub 2}) was detected. The molar ratio of off-gas produced per mole of Np dissolved ranged from 0.25 to 0.4 moles of gas per mole of Np dissolved. A peak off-gas rate of {approx}0.1 scfm/kg bulk oxide was observed. Residual Solids: Pure NpO{sub 2} dissolved with little or no residue with the proposed flowsheet but the NpCo and both sweepings samples left visible solid residue after dissolution. For the NpCo and Part II Sweepings samples the residue amounted to {approx}1% of the initial material, but for the Part I Sweepings sample, the residue amounted to {approx}8 % of the initial material. These residues contained primarily aluminum (Al) and silicon (Si) compounds that did not completely dissolve under the flowsheet conditions. The residues from both sweepings samples contained minor amounts of plutonium (Pu) particles. Overall, the undissolved Np and Pu particles in the residues were a very small fraction of the total solids.

Kyser, E

2009-01-12T23:59:59.000Z

418

Why Sequence Freshwater Iron-Oxidizing Bacteria?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Freshwater Iron-Oxidizing Bacteria? Freshwater Iron-Oxidizing Bacteria? The goal of this project is to obtain complete genome sequences for six different freshwater iron (Fe)-oxidizing bacteria (FeOB). Four of these are oxygen-dependent iron-oxidizing β-proteobacteria, and three of these, Sideroxydans lithotrophicus, Gallionella capsiferriformans, and strain TW-2, are capable of chemolithoautotrophic growth (that is, obtaining energy by the oxidation of inorganic compounds) using Fe(II) as sole energy source under microaerobic (low-oxygen) conditions. The fourth organism, Leptothrix cholodnii, is a sheath-forming heterotrophic (i.e., using complex organic compounds for nutrition) organism that oxidizes both Fe(II) and Mn(II) and deposits a ferromanganic coating on its sheath. In addition,

419

Synergetic effects of mixed copper-iron oxides oxygen carriers in chemical looping combustion  

SciTech Connect (OSTI)

Chemical looping combustion (CLC) is an emerging technology for clean energy production from fuels. CLC produces sequestration-ready CO{sub 2}-streams without a significant energy penalty. Development of efficient oxygen carriers is essential to successfully operate a CLC system. Copper and iron oxides are promising candidates for CLC. Copper oxide possesses high reactivity but it has issues with particle agglomeration due to its low melting point. Even though iron oxide is an inexpensive oxygen carrier it has a slower reactivity. In this study, mixed metal oxide carriers containing iron and copper oxides were evaluated for coal and methane CLC. The components of CuO and Fe{sub 2}O{sub 3} were optimized to obtain good reactivity while maintaining physical and chemical stability during cyclic reactions for methane-CLC and solid-fuel CLC. Compared with single metal oxygen carriers, the optimized Cu–Fe mixed oxide oxygen carriers demonstrated high reaction rate, better combustion conversion, greater oxygen usage and improved physical stability. Thermodynamic calculations, XRD, TGA, flow reactor studies and TPR experiments suggested that there is a strong interaction between CuO and Fe{sub 2}O{sub 3} contributing to a synergistic effect during CLC reactions. The amount of oxygen release of the mixed oxide carrier in the absence of a fuel was similar to that of the single metal oxides. However, in the presence of fuels, the oxygen consumption and the reaction profiles of the mixed oxide carriers were significantly better than that of the single metal oxides. The nature of the fuel not only influenced the reactivity, but also the final reduction status of the oxygen carriers during chemical looping combustion. Cu oxide of the mixed oxide was fully reduced metallic copper with both coal and methane. Fe oxide of the mixed oxide was fully reduced Fe metal with methane but it was reduced to only FeO with coal. Possible mechanisms of how the presence of CuO enhances the reduction of Fe{sub 2}O{sub 3} are discussed.

Siriwardane, Ranjani; Tian, Hanjing; Simonyi, Thomas; Poston, James

2013-06-01T23:59:59.000Z

420

High-efficiency energy transfer due to stimulated orientational scattering of light in nematic liquid crystals  

Science Journals Connector (OSTI)

The saturation stage of stimulated orientational scattering (SOS) of light in thick planarly aligned nematic-liquid-crystal layers was observed and studied experimentally. The power...

Tabiryan, N V; Sukhov, A V; Zel'dovich, B Ya

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Unfamiliar oxidation states and their stabilization  

E-Print Network [OSTI]

ferrate formation. Oxidation of copper(II) hydroxide in alkaline solution with sodium hydroperoxide, Na.OOH, apparently gives copper (III) oxide.8 Determination of the voltage-current curve for a silver anode in sodium hydroxide solution gives breaks... of a knowledge of the chemical prop erties of the substance in question is made apparent by the following illustration: a compound containing silver and oxygen in equal atomic proportions may be made by the oxidation of unipositive silver...

Kleinberg, Jacob

1950-01-01T23:59:59.000Z

422

Solid-oxide fuel cell electrolyte  

DOE Patents [OSTI]

A solid-oxide electrolyte operable at between 600.degree. C. and 800.degree. C. and a method of producing the solid-oxide electrolyte are provided. The solid-oxide electrolyte comprises a combination of a compound having weak metal-oxygen interactions with a compound having stronger metal-oxygen interactions whereby the resulting combination has both strong and weak metal-oxygen interaction properties.

Bloom, Ira D. (Bolingbrook, IL); Hash, Mark C. (Joliet, IL); Krumpelt, Michael (Naperville, IL)

1993-01-01T23:59:59.000Z

423

Reduction of native oxides on InAs by atomic layer deposited Al{sub 2}O{sub 3} and HfO{sub 2}  

SciTech Connect (OSTI)

Thin high-{kappa} oxide films on InAs, formed by atomic layer deposition, are the key to achieve high-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interface between InAs and 2 nm thick Al{sub 2}O{sub 3} or HfO{sub 2} layers using synchrotron x-ray photoemission spectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the native As-oxides and between 10% and 50% of the native In-oxides, depending on the deposition temperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition and the influence of different oxidation states and suboxides is discussed in detail.

Timm, R.; Fian, A.; Hjort, M.; Thelander, C.; Lind, E.; Andersen, J. N.; Wernersson, L.-E.; Mikkelsen, A. [Department of Physics, Nanometer Structure Consortium, Lund University, P.O. Box 118, 22 100 Lund (Sweden)

2010-09-27T23:59:59.000Z

424

High Temperature Oxidation Resistance and Surface Electrical...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

plates with oxidation resistant coatings. Candidate coatings must exhibit chemical and thermal-mechanical stability and high electrical conductivity during long-term...

425

Precursors of copper/zinc oxide catalysts  

Science Journals Connector (OSTI)

Recent results on hydroxycarbonate precursors of copper/zinc oxide catalysts for methanol synthesis are reinterpreted, taking into account earlier work on these systems.

M.S. Spencer

426

Vapor phase modifiers for oxidative coupling  

DOE Patents [OSTI]

Volatilized metal compounds are described which are capable of retarding vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, B.K.

1991-12-17T23:59:59.000Z

427

Double perovskite catalysts for oxidative coupling  

DOE Patents [OSTI]

Alkali metal doped double perovskites containing manganese and at least one of cobalt, iron and nickel are useful in the oxidative coupling of alkane to higher hydrocarbons.

Campbell, K.D.

1991-01-01T23:59:59.000Z

428

Lanthanide doped barium phosphorous oxide scintillators  

DOE Patents [OSTI]

The present invention provides for a composition comprising an inorganic scintillator comprising a lanthanide-doped barium phosphorous oxide useful for detecting nuclear material.

Borade, Ramesh B; Bourret-Courchesne, Edith; Denzo, Stephen E

2013-02-26T23:59:59.000Z

429

Breakout Group 5: Solid Oxide Fuel Cells  

Broader source: Energy.gov (indexed) [DOE]

Oxide Fuel Cells PARTICIPANTS Name Organization Robert Ploessl Corning, Inc. Tim Armstrong Oak Ridge National Laboratory Barbara Heydorn SRI International Suresh Baskaran...

430

NETL: Solid Oxide Fuel Cells Publications  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Solid Oxide Fuel Cells Publications Operating Principles AEC Development Atmospheric Pressure Systems Pressurized Systems Program Plan Project Portfolio Project Information Systems...

431

How to overcome the oxide barrier | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

oxide semiconductor Atomistic diagram for crystalline chromium metal (light blue) on strontium titanate(top), an equation that describes the transport process (middle), and an...

432

Cation Defects and Conductivity in Transparent Oxides  

SciTech Connect (OSTI)

High quality doped zinc oxide and mixed transition metal spinel oxide films have been deposited by means of sputter deposition from metal and metal oxide targets, and by spin casting from aqueous or alcoholic precursor solutions. Deposition conditions and post-deposition processing are found to alter cation oxidation states and their distributions in both oxide materials resulting in marked changes to both optical transmission and electrical response. For ZnO, partial reduction of the neat or doped material by hydrogen treatment of the heated film or by electrochemical processing renders the oxide n-type conducting. Continued reduction was found to diminish conductivity. In contrast, oxidation of the infrared transparent p-type spinel conductors typified by NiCo2O4 was found to increase conductivity. The disparate behavior of these two materials is caused in part by the sign of the charge carrier and by the existence of two different charge transport mechanisms that are identified as free carrier conduction and polaron hopping. While much work has been reported concerning structure/property relationships in the free carrier conducting oxides, there is a significantly smaller body of information on transparent polaron conductors. In this paper, we identify key parameters that promote conductivity in mixed metal spinel oxides and compare their behavior with that of the free carrier TCO’s.

Exarhos, Gregory J.; Windisch, Charles F.; Ferris, Kim F.; Owings, Robert R.

2007-10-24T23:59:59.000Z

433

Photosynthetic water oxidation versus photovoltaic water electrolysis  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

News Media about Center Center Video Library Bisfuel Picture Gallery Photosynthetic water oxidation versus photovoltaic water electrolysis 13 May 2011 Professor Tom Moore, a...

434

Oxidative Remobilization of Technetium Sequestered by Sulfide...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Remobilization of Technetium Sequestered by Sulfide-Transformed Nano Zerovalent Iron. Oxidative Remobilization of Technetium Sequestered by Sulfide-Transformed Nano Zerovalent...

435

Graphene oxide/poly(acrylic acid) hydrogel by ?-ray pre-irradiation on graphene oxide surface  

Science Journals Connector (OSTI)

Graphene oxide/poly(acrylic acid) (GO/PAA)...?...-ray pre-irradiation technique. The functional groups in graphene oxide were modified to peroxide in an...2 environment with ?...-ray radiation. Radical species fr...

Sungyoung Lee; Hoik Lee; Jae Hyun Sim; Daewon Sohn

2014-02-01T23:59:59.000Z

436

S.O.S. APPROXIMATION OF POLYNOMIALS, NONNEGATIVE ON A ...  

E-Print Network [OSTI]

The case of a semi-algebraic set K = {x ? Rn|gj(x) ? 0, j = 1,...,m} reduces to the case of an .... [Mr(y)(1,j) = y? and Mr(y)(i, 1) = y?] ? Mr(y)(i, j) = y?+?. (2.3) ...

2005-08-20T23:59:59.000Z

437

Microsoft Word - SoS Hdwr Manual Rev03.doc  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

03 Shad-o-Snap, RadEye and ShadoCam are trademarks of Rad-icon Imaging Corp. All other brand and product names are trademarks or registered trademarks of their respective...

438

CeSOS Highlights and AMOS Visions Conference  

E-Print Network [OSTI]

-year Master's programmes 80% of Norway's Masters in Engineering (Sivilingeniør) 300- 350 doctoral degrees) Multiphase Flow Assurance Innovation center FME Nowitech (-2017) Norwegian Research Center for Offshore Wind) Center for Environmental design of Renewable Energy FME ZEB (-2017) Zero Emmission Buildings FME Cenbio

Nørvåg, Kjetil

439

Oxidation of the flavonol fisetin by polyphenol oxidase  

Science Journals Connector (OSTI)

The present study demonstrates the antiradical efficiency of fisetin, a flavonol widely distributed in fruits and vegetables, by its ability to react with two different free radicals, ABTS+? and DPPH?. The polyphenolic nature of fisetin led us to consider whether it might be oxidised by polyphenol oxidase (PPO), and the results reported show that it can be oxidised by PPO extracted and partially purified from broad bean seeds. The reaction was followed by recording spectral changes with time, with maximal spectral changes being observed at 282 nm (increase in absorbance) and at 362 nm (decrease). The presence of two isosbectic points (at 265 and 304 nm) suggested that only one absorbent product was formed. These spectral changes were not observed in the absence of PPO. The oxidation rate varied with the pH, reaching its highest value at pH 5.5. The fisetin oxidation rate increased in the presence of sodium dodecyl sulfate, an activator of polyphenol oxidase. Maximal activity was obtained at 0.87 mM sodium dodecyl sulfate. The following kinetic parameters were determined: Vmax=49 ?M/min, Km=0.6 mM, Vmax/Km=8.2×10?2 min?1. Flavonol oxidation was inhibited by selective PPO inhibitors such as cinnamic acid (a classical competitive inhibitor, Ki=1.4 mM) and 4-hexylresorcinol, which behaved as a slow-binding inhibitor. The results reported show that fisetin oxidation was strictly dependent on the presence of polyphenol oxidase.

Mercedes Jiménez; Josefa Escribano-Cebrián; Francisco Garc??a-Carmona

1998-01-01T23:59:59.000Z

440

Zn Sorption Mechanisms onto Sheathed Leptothrix Discophora and the Impact of the Nanoparticulate Biogenic Mn Oxide Coating  

SciTech Connect (OSTI)

Zinc sorption on sheathed Leptothrix discophora bacterium, the isolated extracellular polymeric substances (EPS) sheath, and Mn oxide-coated bacteria was investigated with macroscopic and spectroscopic techniques. Complexation with L. discophora was dominated by the outer membrane phosphoryl groups of the phospholipid bilayer while sorption to isolated EPS was dominated by carboxyl groups. Precipitation of nanoparticulate Mn oxide coatings on the cell surface increased site capacity by over twenty times with significant increase in metal sorption. XAS analysis of Zn sorption in the coated system showed Mn oxide phase contributions of 18 to 43% through mononuclear inner-sphere complexes. The coordination environments in coprecipitation samples were identical to those of sorption samples, indicating that, even in coprecipitation, Zn is not incorporated into the Mn oxide structure. Rather, through enzymatic oxidation by L. discophora, Mn(II) is oxidized and precipitated onto the biofilm providing a large surface for metal sequestration. The nanoparticulate Mn oxide coating exhibited significant microporosity (75%) suggesting contributions from intraparticle diffusion. Transient studies conducted over 7 months revealed a 170% increase in Zn loading. However, the intraparticle diffusivity of 10{sup -19} cm{sup 2} s{sup -1} is two orders of magnitude smaller than that for abiotic Mn oxide which we attribute to morphological changes such as reduced pore sizes in the nanoparticulate oxide. Our results demonstrate that the cell-bound Mn oxide particles can sorb significant amounts of Zn over long periods of time representing an important surface for sequestration of metal contaminants.

Boonfueng, T.; Axe, L; Yee, N; Hahn, D; Ndiba, P

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Tin oxide-titanium oxide/graphene composited as anode materials for lithium-ion batteries  

Science Journals Connector (OSTI)

A tin oxide-titanium oxide/graphene (SnO2-TiO2.../G) ternary nanocomposite as high-performance anode for Li-ion batteries was prepared via a simple reflux method. ... The graphite oxide (GO) was reduced to graphene

Shan-Shan Chen; Xue Qin

2014-10-01T23:59:59.000Z

442

Correlating Catalytic Methanol Oxidation with the Structure and Oxidation State of Size-Selected Pt Nanoparticles  

E-Print Network [OSTI]

of this process is a limiting factor in the performance of direct methanol fuel cells, which produce electricityCorrelating Catalytic Methanol Oxidation with the Structure and Oxidation State of Size-Selected Pt nanoparticles (NPs) prepared by micelle encapsulation and supported on -Al2O3 during the oxidation of methanol

Kik, Pieter

443

The role of nitric oxide in testosterone-induced vasodilation in pig coronary arteries and rat thoracic aorta  

E-Print Network [OSTI]

Several studies have provided evidence that the administration of testosterone to vascular tissue causes vasodilation (Costarella, Yue). This study examines the role of nitric oxide (NO) as a potential mechanism of testosterone-induced vasodilation...

Piefer, Jason William

2013-02-22T23:59:59.000Z

444

Structural insight into the oxidation-sensing mechanism of the antibiotic resistance of regulator MexR  

SciTech Connect (OSTI)

MexR functions as the primary regulator of the mexAB-oprM multidrug efflux expression in Pseudomonas aeruginosa. It has been shown that MexR senses oxidative stress by interprotomer disulphide bond formation between redox-active cysteines. This oxidation induces MexR to dissociate from the promoter DNA, thus activating the transcriptional expression of efflux pump genes. In this study, we present the crystal structure of MexR in its oxidized form at a resolution of 2.1 {angstrom}. This crystal structure reveals the mechanism by which oxidative signal allosterically derepresses the MexR-controlled transcription activation.

Chen, Hao; Yi, Chengqi; Zhang, Jin; Zhang, Wenru; Ge, Zhiyun; Yang, Cai-Guang; He, Chuan (UC); (Chinese Aca. Sci.); (Nanjing)

2010-11-05T23:59:59.000Z

445

Lactose oxidation kinetics with oxygen in catalyst-solution-gas three-phase system with simultaneous electrical potential measurement of supported gold catalyst  

Science Journals Connector (OSTI)

Lactose oxidation kinetics was studied on an supported gold catalyst with simultaneous control of catalyst potential. The experimental data were described well...

D. Yu. Murzin; E. V. Murzina; A. V. Tokarev…

2009-09-01T23:59:59.000Z

446

Tunneling oxide engineering by ion implantation of nitrogen for 3D vertical silicon pillar SONOS flash memory  

Science Journals Connector (OSTI)

The electrical characteristics of silicon-oxide-nitride-oxide-silicon (SONOS) flash memory with a 3D vertical silicon pillar structure were studied. As an alternative method for the formation of the tunneling oxide, nitrogen ion implantation was applied to thermally grown pure silicon dioxide with a low energy (5 keV). The devices show significant improvement in the erase characteristics compared to conventional tunneling oxide. Secondary ion mass spectrometry was used to analyze the nitrogen distribution within tunnel oxide, and the improved erase properties can be attributed to the incorporation of about 4.8% nitrogen (2 × 1021 atoms/cm3) into the tunnel oxide formed by nitrogen ion implantation.

Jae-Sub Oh; Seong-Dong Yang; Sang-Youl Lee; Young-Su Kim; Min-Ho Kang; Sung-Kyu Lim; Hi-Deok Lee; Ga-Won Lee

2013-01-01T23:59:59.000Z

447

Investigation of Self-Assembly and Micelle Polarity for a Wide Range of Ethylene Oxide-Propylene Oxide-Ethylene  

E-Print Network [OSTI]

Investigation of Self-Assembly and Micelle Polarity for a Wide Range of Ethylene Oxide-Propylene Oxide-Ethylene Oxide Block Copolymers in Water Josias R. Lopes and Watson Loh* Instituto de Qui of 15 EO-PO-EO (EO ) ethylene oxide, PO ) propylene oxide) block copolymers by using three different

Loh, Watson

448

Increased Cytotoxicity of Oxidized Flame Soot  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Increased Cytotoxicity of Oxidized Flame Soot Increased Cytotoxicity of Oxidized Flame Soot Title Increased Cytotoxicity of Oxidized Flame Soot Publication Type Journal Article Year of Publication 2012 Authors Holder, Amara L., Brietta J. Carter, Regine Goth-Goldstein, Donald Lucas, and Catherine P. Koshland Journal Atmospheric Pollution Research Volume 3 Start Page 25 Issue 1 Pagination 25-31 Date Published 01/2012 Keywords health effects, ozone, soot, toxicity Abstract Combustion-generated particles released into the atmosphere undergo reactions with oxidants, which can change the particles' physiochemical characteristics. In this work, we compare the physical and chemical properties and cellular response of particles fresh from a flame with those oxidized by ozone and nitrogen dioxide. The reaction with ozone and nitrogen dioxide does not significantly modify the physical characteristics of the particles (primary particle size, fractal dimension, and surface area). However, oxidation affects the chemical characteristics of the particles, creating more oxygen and nitrogen containing functional groups, and increases their hydrophilicity. In addition, oxidized soot generates more reactive oxygen species, as measured by the dithiothreitol (DTT) assay. Furthermore, oxidized soot is 1.5-2 times more toxic than soot that was not reacted with ozone, but the inflammatory response, measured by interleukin-8 (IL-8) secretion, is unchanged. These results imply that combustion-generated particles released into the atmosphere will have an increased toxicity on or after high ozone days.

449

Constraining Mercury Oxidation Using Wet Deposition  

E-Print Network [OSTI]

Constraining Mercury Oxidation Using Wet Deposition Noelle E. Selin and Christopher D. Holmes mercury oxidation [Selin & Jacob, Atmos. Env. 2008] 30 60 90 120 150 30 60 90 120 150 30 60 90 120 150 30 Influences on Mercury Wet Deposition · Hg wet dep = f(precipitation, [Hg(II)+Hg(P)]) Correlation (r2) between

Selin, Noelle Eckley

450

Nanocomposite of graphene and metal oxide materials  

SciTech Connect (OSTI)

Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10C.

Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

2012-09-04T23:59:59.000Z

451

The High-Temperature Oxidation of Propane  

Science Journals Connector (OSTI)

...research-article The High-Temperature Oxidation of Propane J. W. Falconer J. H. Knox Above 400 degrees C propane is oxidized by a two-stage degenerately...of propylene becomes important. While propane still in the main reacts to form propylene...

1959-01-01T23:59:59.000Z

452

Apparatus and method for oxidizing organic materials  

DOE Patents [OSTI]

The invention is a method and apparatus using high cerium concentration in the anolyte of an electrochemical cell to oxidize organic materials. The method and apparatus further use an ultrasonic mixer to enhance the oxidation rate of the organic material in the electrochemical cell. 6 figs.

Surma, J.E.; Bryan, G.H.; Geeting, J.G.H.; Butner, R.S.

1998-01-13T23:59:59.000Z

453

nitrogen oxides | OpenEI  

Open Energy Info (EERE)

20 20 Varnish cache server Browse Upload data GDR 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation: XID: 2142279720 Varnish cache server nitrogen oxides Dataset Summary Description Emissions from energy use in buildings are usually estimated on an annual basis using annual average multipliers. Using annual numbers provides a reasonable estimation of emissions, but it provides no indication of the temporal nature of the emissions. Therefore, there is no way of understanding the impact on emissions from load shifting and peak shaving technologies such as thermal energy storage, on-site renewable energy, and demand control. Source NREL Date Released April 11th, 2011 (3 years ago) Date Updated April 11th, 2011 (3 years ago)

454

Evaporative oxidation treatability test report  

SciTech Connect (OSTI)

In 1992, Congress passed the Federal Facilities Compliance Act that requires the U.S. Department of Energy (DOE) to treat and dispose of its mixed waste in accordance with the Resource Conservation and Recovery Act (RCRA) land disposal restrictions (LDRs). In response to the need for mixed-waste treatment capacity where available off-site commercial treatment facilities do not exist or cannot be used, the DOE Albuquerque Operations Office (DOE-AL) organized a Treatment Selection Team to match mixed wastes with treatment options and develop a strategy for treatment of its mixed wastes. DOE-AL manages operations at nine sites with mixed-waste inventories. The Treatment Selection Team determined a need to develop mobile treatment capacity to treat wastes at the sites where the wastes are generated. Treatment processes used for mixed waste not only must address the hazardous component (i.e., meet LDRs) but also must contain the radioactive component in a form that allows final disposal while protecting workers, the public, and the environment. On the basis of recommendations of the Treatment Selection Team, DOE-AL assigned projects to the sites to bring mixed-waste treatment capacity on-line. The three technologies assigned to the DOE Grand Junction Projects Office (GJPO) are evaporative oxidation, thermal desorption, and treated wastewater evaporation. Rust Geotech, the DOE-GJPO prime contractor, was assigned to design and fabricate mobile treatment units (MTUs) for these three technologies and to deliver the MTUs to selected DOE-AL sites. To conduct treatability tests at the GJPO, Rust leased a pilot-scale evaporative oxidation unit from the Clemson Technical Center (CTC), Anderson, South Carolina. The purpose of this report is to document the findings and results of tests performed using this equipment.

NONE

1995-04-01T23:59:59.000Z

455

EIA - Greenhouse Gas Emissions - Nitrous Oxide Emissions  

Gasoline and Diesel Fuel Update (EIA)

4. Nitrous Oxide Emissions 4. Nitrous Oxide Emissions 4.1 Total emissions U.S. nitrous oxide emissions in 2009 were 4 MMTCO2e (1.7 percent) below their 2008 total (Table 22). Sources of U.S. nitrous oxide emissions include agriculture, energy use, industrial processes, and waste management (Figure 22). The largest source is agriculture (73 percent), and the majority of agricultural emissions result from nitrogen fertilization of agricultural soils (87 percent of the agriculture total) and management of animal waste (13 percent). U.S. nitrous oxide emissions rose from 1990 to 1994, fell from 1994 to 2002, and returned to an upward trajectory from 2003 to 2007, largely as a result of increased use of synthetic fertilizers. Fertilizers are the primary contributor of emissions from nitrogen fertilization of soils, which grew by more than 30 percent from

456

Two Dimensional Polymer That Generates Nitric Oxide.  

DOE Patents [OSTI]

A polymeric composition that generates nitric oxide and a process for rendering the surface of a substrate nonthrombogenic by applying a coating of the polymeric composition to the substrate are disclosed. The composition comprises: (1) a crosslinked chemical combination of (i) a polymer having amino group-containing side chains along a backbone forming the polymer, and (ii) a crosslinking agent containing functional groups capable of reacting with the amino groups; and (2) a plurality of nitric oxide generating functional groups associated with the crosslinked chemical combination. Once exposed to a physiological environment, the coating generates nitric oxide thereby inhibiting platelet aggregation. In one embodiment, the nitric oxide generating functional groups are provided by a nitrated compound (e.g., nitrocellulose) imbedded in the polymeric composition. In another embodiment, the nitric oxide generating functional groups comprise N2O2- groups covalently bonded to amino groups on the polymer.

McDonald, William F. (Utica, OH); Koren, Amy B. (Lansing, MI)

2005-10-04T23:59:59.000Z

457

Effect of Gadolinium Doping on the Air Oxidation of Uranium Dioxide  

SciTech Connect (OSTI)

Researchers at the Pacific Northwest National Laboratory (PNNL) investigated the effects of gadolinia concentration on the air oxidization of gadolinia-doped uranium dioxide using thermogravimetry and differential scanning calorimetry to determine if such doping could improve uranium dioxide's stability as a nuclear fuel during potential accident scenarios in a nuclear reactor or during long-term disposal. We undertook this study to determine whether the resistance of the uranium dioxide to oxidation to the orthorhombic U3O8 with its attendant crystal expansion could be prevented by addition of gadolinia. Our studies found that gadolinium has little effect on the thermal initiation of the first step of the reported two-step air oxidation of UO2; however, increasing gadolinia content does stabilize the initial tetragonal or cubic product allowing significant oxidation before the second expansive step to U3O8 begins.

Scheele, Randall D.; Hanson, Brady D.; Cumblidge, Stephen E.; Jenson, Evan D.; Kozelisky, Anne E.; Sell, Rachel L.; MacFarlan, Paul J.; Snow, Lanee A.

2004-12-04T23:59:59.000Z

458

Selective production of methanol from syngas over LaTi1?xCuxO3 mixed oxides  

Science Journals Connector (OSTI)

Carbon monoxide hydrogenation was studied over partially substituted copper-containing LaTi1?xCuxO3 oxides and on copper supported on La2O3. The unsubstituted (x = 0) oxide was weakly active for CO hydrogenation,...

R. van Grieken; J. L. Peña; A. Lucas; G. Calleja; M. L. Rojas…

1991-01-01T23:59:59.000Z

459

Revealing the Nature of Emergent Ferromagnetism at an Oxide Heterointe...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of thin-film structures 6-8. LaAlO3 (lanthanum aluminium oxide, LAO) and SrTiO3 (strontium titanium oxide, STO) materials are perovskites, a class of mineral oxides whose...

460

Perfluorodiethoxymethane on nickel and nickel oxide surfaces  

SciTech Connect (OSTI)

The interaction of perfluorodiethoxymethane with a nickel single crystal, Ni(100); a nickel crystal with chemisorbed oxygen, Ni(100)-c(2x2)O; and a nickel crystal with nickel oxide crystallites, NiO(100) is investigated in an ultra high vacuum environment using thermal desorption spectroscopy and high resolution electron energy loss spectroscopy. Nickel, a component of hard disk drives and stainless steel, is used to represent metal surfaces in these {open_quotes}real{close_quotes} systems. Perfluorodiethoxymethane is used in this study as a model compound of industrial perfluoropolyether lubricants. These lubricants are known for their exceptional stability, except in the presence of metals. Perfluorodiethoxymethane contains the acetal group (-OCF{sub 2}O-), believed to be particularly vulnerable to attack in the presence of Lewis acids. Since the surfaces studied show increasing Lewis acidity at the nickel atom sites, one might expect to see increasing decomposition of perfluorodiethoxymethane due to acidic attack of the acetal group. No decomposition of perfluorodiethoxymethane is observed on the clean Ni(100) surface, while more research is needed to determine whether a small decomposition pathway is observed on the oxygenated surfaces, or whether sample impurities are interfering with results. The strength of the bonding of perfluorodiethoxymethane to the surface is found to increase as the nickel atoms sites become more acidic in moving from Ni(100) to Ni (100)-c(2x2)O to NiO (100).

Jacobson, J.

1994-03-03T23:59:59.000Z

Note: This page contains sample records for the topic "oxidants study sos" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Oxidative reactions and their impact on the properties of asphalt as a pavement binder  

E-Print Network [OSTI]

OXIDATIVE REACTIONS AND THEIR IMPACT ON THE PROPERTIES OF ASPHALT AS A PAVE~ BINDER A Thesis by CHEE KEUNG LAU Submitted to the Office of Graduate Studies of Texas A & M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1991 Major Subject: Chemical Engineering OXIDATIVE REACTIONS AND THEIR IMPACT ON THE PROPERTIES OF ASPHALT AS A PAVEMENT BINDER A Thesis by CHEE KEUNG LAU Approved as to style and content by: Charles J. over (Chair...

Lau, Chee Keung

1991-01-01T23:59:59.000Z

462

Quantitative X-ray microanalysis of submicron carbide formation in chromium (III) oxide rich scale  

SciTech Connect (OSTI)

This paper discusses the chemical microanalysis techniques adapted to identify the precipitates that form on the surface of, or within, the oxide scale of a Fe-22Cr ferritic steel during exposure to a carbon-monoxide rich environment at 750C for 800 hours. Examination of oxidized test coupons revealed the presence of a fiber like structure at the surface, shown in figure 1. Other studies have reported that these structures are carbon precipitates.

Collins, W.K.; Ziomek-Moroz, M.; Holcomb, G.R.; Danielson, P.; Hunt, A.H

2007-08-01T23:59:59.000Z

463

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

SciTech Connect (OSTI)

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, 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.

Lany, S.; Peng, H.; Ndione, P.; Zakutayev, A.; Ginley, D. S.

2013-01-01T23:59:59.000Z

464

Redox cycle stability of mixed oxides used for hydrogen generation in the cyclic water gas shift process  

SciTech Connect (OSTI)

Graphical abstract: - Highlights: • Fe{sub 2}O{sub 3} modified with CaO, SiO{sub 2} and Al{sub 2}O{sub 3} was studied in cyclic water gas shift reactor. • For the first time stability of such oxides were tested for 100 redox cycles. • Optimally added oxides significantly improved the activity and the stability of Fe{sub 2}O{sub 3}. • Increased stability was attributed to the impediment of neck formation. - Abstract: Repeated cycles of the reduction of Fe{sub 3}O{sub 4} with reductive gas, e.g. hydrogen and subsequent oxidation of the reduced iron material with water vapor can be harnessed as a process for the production of pure hydrogen. The redox behavior of iron oxide modified with various amounts of SiO{sub 2}, CaO and Al{sub 2}O{sub 3} was investigated in the present study. The total amount of the additional metal oxides was always below 15 wt%. The samples were prepared by co-precipitation using urea hydrolysis method. The influence of various metal oxides on the hydrogen production capacity and the material stability was studied in detail in terms of temperature-programmed reduction (TPR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET analysis. Furthermore, the activity and the stability of the samples were tested in repeated reduction with diluted H{sub 2} and re-oxidation cycles with H{sub 2}O. The results indicate that combination of several oxides as promoter increases the stability of the iron oxide material by mitigating the sintering process. The positive influence of the oxides in stabilizing the iron oxide material is attributed to the impediment of neck formation responsible for sintering.

Datta, Pradyot, E-mail: pradyot.datta@gmail.com

2013-10-15T23:59:59.000Z

465

Wiremesh Substrates for Enhanced Particulate Oxidation and Efficient...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Wiremesh Substrates for Enhanced Particulate Oxidation and Efficient Urea SCR NOx Reduction Wiremesh Substrates for Enhanced Particulate Oxidation and Efficient Urea SCR NOx...

466

High surface area, electrically conductive nanocarbon-supported metal oxide  

DOE Patents [OSTI]

A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust.

Worsley, Marcus A; Han, Thomas Yong-Jin; Kuntz, Joshua D; Cervanted, Octavio; Gash, Alexander E; Baumann, Theodore F; Satcher, Jr., Joe H

2014-03-04T23:59:59.000Z

467

Polyelectrolyte-Induced Reduction of Exfoliated Graphite Oxide...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Reduction of Exfoliated Graphite Oxide: A Facile Route to Synthesis of Soluble Graphene Nanosheets. Polyelectrolyte-Induced Reduction of Exfoliated Graphite Oxide: A Facile...

468

Rational Catalyst Design Applied to Development of Advanced Oxidation...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Catalyst Design Applied to Development of Advanced Oxidation Catalysts for Diesel Emission Control Rational Catalyst Design Applied to Development of Advanced Oxidation...

469

Effects of Diesel Exhaust Emissions on Soot Oxidation and DPF...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Diesel Exhaust Emissions on Soot Oxidation and DPF Regeneration Effects of Diesel Exhaust Emissions on Soot Oxidation and DPF Regeneration DPF regeneration experiments verified the...

470

Arginine-Containing Ligands Enhance H-2 Oxidation Catalyst Performance...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Arginine-Containing Ligands Enhance H-2 Oxidation Catalyst Performance. Arginine-Containing Ligands Enhance H-2 Oxidation Catalyst Performance. Abstract: In H2 fuel cells,...

471

Cryogenic CO2 Formation on Oxidized Gold Clusters Synthesized...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Cryogenic CO2 Formation on Oxidized Gold Clusters Synthesized via Reactive Layer Assisted Deposition. Cryogenic CO2 Formation on Oxidized Gold Clusters Synthesized via Reactive...

472

Photoluminescence Properties of Alkaline-Earth Oxide Nanoparticles...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Properties of Alkaline-Earth Oxide Nanoparticles. Photoluminescence Properties of Alkaline-Earth Oxide Nanoparticles. Abstract: Previous experiments have demonstrated that...

473

Robust control strategies for hybrid solid oxide fuel cell systems.  

E-Print Network [OSTI]

??Solid Oxide Fuel Cell (SOFC) systems are electrochemical energy conversion devices characterized by the use of solid oxide as the electrolyte. They operate at high… (more)

Mathew, Anju Ann

2010-01-01T23:59:59.000Z

474

Biostimulation of Iron Reduction and Subsequent Oxidation of...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Biostimulation of Iron Reduction and Subsequent Oxidation of Sediment Containing Fe-silicates and Fe-oxides: Effect of Redox Biostimulation of Iron Reduction and Subsequent...

475

Graphene/metal Oxide Nanocomposites for Li-ion Batteries  

Science Journals Connector (OSTI)

Our work focuses on preparing the graphene/metal oxide nanocomposites by facile methold and exploring the graphene/metal oxide composites with unique structural or compositions for...

Liang, Junfei; Li, Lidong; Guo, Lin

476

Enzyme-free Detection of Hydrogen Peroxide from Cerium Oxide...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

free Detection of Hydrogen Peroxide from Cerium Oxide Nanoparticles Immobilized on Poly(4-vinylpyridine) Self-Assembled Enzyme-free Detection of Hydrogen Peroxide from Cerium Oxide...

477

Impact of the Fuel Molecular Structure on the Oxidation Process...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Oxidation Process of Real Diesel fuels According to Storage Conditions and Biodiesel Content Impact of the Fuel Molecular Structure on the Oxidation Process of Real Diesel fuels...

478

EIS-0360: Depleted Uranium Oxide Conversion Product at the Portsmouth...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

60: Depleted Uranium Oxide Conversion Product at the Portsmouth, Ohio Site EIS-0360: Depleted Uranium Oxide Conversion Product at the Portsmouth, Ohio Site Summary This...

479

Solid Oxide Membrane (SOM) Electrolysis of Magnesium: Scale-Up...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Solid Oxide Membrane (SOM) Electrolysis of Magnesium: Scale-Up Research and Engineering for Light-Weight Vehicles Solid Oxide Membrane (SOM) Electrolysis of Magnesium: Scale-Up...

480

Interactions of nickel/zirconia solid oxide fuel cell anodes...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Interactions of nickelzirconia solid oxide fuel cell anodes with coal gas containing arsenic. Interactions of nickelzirconia solid oxide fuel cell anodes with coal gas containing...