Sample records for vanadium redox flow

  1. Fact Sheet: Vanadium Redox Flow Batteries (October 2012) | Department...

    Energy Savers [EERE]

    Batteries (October 2012) Fact Sheet: Vanadium Redox Flow Batteries (October 2012) DOE's Energy Storage Program is funding research to develop next-generation vanadium redox flow...

  2. A Stable Vanadium Redox-Flow Battery with High Energy Density...

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

    Stable Vanadium Redox-Flow Battery with High Energy Density for Large-scale Energy Storage. A Stable Vanadium Redox-Flow Battery with High Energy Density for Large-scale Energy...

  3. Accepted Manuscript Title: Dramatic Performance Gains in Vanadium Redox Flow

    E-Print Network [OSTI]

    Mench, Matthew M.

    ) are a potentially enabling technology for intermittent, renewable energy sources such as wind and solar power [1, for most stationary power uses, the #12;Page 3 of 18 Accepted M anuscript energy density per seAccepted Manuscript Title: Dramatic Performance Gains in Vanadium Redox Flow Batteries Through

  4. Numerical modeling of an all vanadium redox flow battery.

    SciTech Connect (OSTI)

    Clausen, Jonathan R.; Brunini, Victor E.; Moffat, Harry K.; Martinez, Mario J.

    2014-01-01T23:59:59.000Z

    We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.

  5. Membraneless Vanadium Redox Fuel Cell Using Laminar Flow Rosaria Ferrigno, Abraham D. Stroock, Thomas D. Clark, Michael Mayer, and

    E-Print Network [OSTI]

    Prentiss, Mara

    Membraneless Vanadium Redox Fuel Cell Using Laminar Flow Rosaria Ferrigno, Abraham D. Stroock This communication describes a small redox fuel cell fabricated using a design that omits the membrane normally used this concept by operating a millimeter-scale redox fuel cell that uses the redox couples V(V)/V(IV) (cathodic

  6. Nitrogen-doped mesoporous carbon for energy storage in vanadium redox flow batteries

    SciTech Connect (OSTI)

    Shao, Yuyan; Wang, Xiqing; Engelhard, Mark H.; Wang, Chong M.; Dai, Sheng; Liu, Jun; Yang, Zhenguo; Lin, Yuehe

    2010-03-22T23:59:59.000Z

    We demonstrate a novel electrode material?nitrogen-doped mesoporous carbon (NMC)?for vanadium redox flow batteries. Mesoporous carbon (MC) is prepared using a soft-template method and doped with nitrogen by heat-treating MC in NH3. NMC is characterized with X-ray photoelectron spectroscopy and transmission electron microscopy. The redox reaction of VO2+/VO2+ is characterized with cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic kinetics of the redox couple VO2+/VO2+ is significantly enhanced on NMC electrode compared with MC and graphite electrodes. The reversibility of the redox couple VO2+/VO2+ is greatly improved on NMC (0.61 for NMC vs. 0.34 for graphite). Nitrogen doping facilitates the electron transfer on the electrode/electrolyte interface for both oxidation and reduction processes. NMC is a promising electrode material for redox flow batteries.

  7. Upgrading the Vanadium Redox Battery | EMSL

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

    Upgrading the Vanadium Redox Battery Upgrading the Vanadium Redox Battery New electrolyte mix increases energy storage by 70 percent After developing a more effective...

  8. Nuclear Magnetic Resonance Studies on Vanadium(IV) Electrolyte Solutions for Vanadium Redox Flow Battery

    SciTech Connect (OSTI)

    Vijayakumar, M.; Burton, Sarah D.; Huang, Cheng; Li, Liyu; Yang, Zhenguo; Graff, Gordon L.; Liu, Jun; Hu, Jian Z.; Skyllas-Kazacos, Maria

    2010-11-15T23:59:59.000Z

    The vanadium (IV) electrolyte solutions with various vanadium concentrations are studied by variable temperature 1H and 17O Nuclear Magnetic Resonance (NMR) spectroscopy. The structure and kinetics of vanadium (IV) species in the electrolyte solutions are explored with respect to vanadium concentration and temperature. It was found that the vanadium (IV) species exist as hydrated vanadyl ion, i.e. [VO(H2O)5]2+ forming an octahedral coordination with vanadyl oxygen in the axial position and the remaining positions occupied by water molecules. This hydrated vanadyl ion structure is stable in vanadium concentrations up to 3M and in the temperature range of 240 to 340 K. The sulfate anions in the electrolyte solutions are found to be weekly bound to this hydrated vanadyl ion and occupies its second coordination sphere. The possible effects of these sulfate anions in proton and water exchange between vanadyl ion and solvent molecules are discussed based on 1H and 17O NMR results.

  9. Nitrogen-doped mesoporous carbon for energy storage in vanadium redox flow batteries

    SciTech Connect (OSTI)

    Dai, Sheng [ORNL; Shao, Yuyan [Pacific Northwest National Laboratory (PNNL); Wang, Xiqing [ORNL; Engelhard, Mark H [Pacific Northwest National Laboratory (PNNL); Wang, Congmin [ORNL; Liu, Jun [Pacific Northwest National Laboratory (PNNL); YANG, ZHENGUO [Pacific Northwest National Laboratory (PNNL); Lin, Yuehe [ORNL

    2010-01-01T23:59:59.000Z

    We demonstrate an excellent performance of nitrogen-doped mesoporous carbon (N-MPC) for energy storage in vanadium redox flow batteries. Mesoporous carbon (MPC) is prepared using a soft-template method and doped with nitrogen by heat-treating MPC in NH{sub 3}. N-MPC is characterized with X-ray photoelectron spectroscopy and transmission electron microscopy. The redox reaction of [VO]{sup 2+}/[VO{sub 2}]{sup +} is characterized with cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic kinetics of the redox couple [VO]{sup 2+}/[VO{sub 2}]{sup +} is significantly enhanced on N-MPC electrode compared with MPC and graphite electrodes. The reversibility of the redox couple [VO]{sup 2+}/[VO{sub 2}]{sup +} is greatly improved on N-MPC (0.61 for N-MPC vs. 0.34 for graphite), which is expected to increase the energystorage efficiency of redoxflowbatteries. Nitrogen doping facilitates the electron transfer on electrode/electrolyte interface for both oxidation and reduction processes. N-MPC is a promising material for redoxflowbatteries. This also opens up new and wider applications of nitrogen-doped carbon.

  10. Nanorod Niobium Oxide as Powerful Catalysts for an All Vanadium Redox Flow Battery

    SciTech Connect (OSTI)

    Li, Bin; Gu, Meng; Nie, Zimin; Wei, Xiaoliang; Wang, Chong M.; Sprenkle, Vincent L.; Wang, Wei

    2014-01-01T23:59:59.000Z

    Graphite felts (GFs), as typical electrode materials for all vanadium redox flow batteries (VRBs), limit the cell operation to low current density because of their poor kinetic reversibility and electrochemical activity. Here, in order to address this issue we report an electrocatalyst, Nb2O5, decorating the surface of GFs to reduce the activation barrier for redox conversion. Nb2O5 nanofibers with monoclinic phases are synthesized by hydrothermal method and deposited on GFs, which is confirmed to have catalytic effects towards redox couples of V(II)/V(III) at the negative side and V(IV)/V(V) at the positive side, and thus applied in both electrodes of VRB cells. Due to the low conductivity of Nb2O5, the performance of electrodes heavily depends on the nano size and uniform distribution of catalysts on GFs surfaces. The addition of the water-soluble compounds containing W element into the precursor solutions facilitates the precipitation of nanofibers on the GFs. Accordingly, an optimal amount of W-doped Nb2O5 nanofibers with weaker agglomeration and better distribution on GFs surfaces are obtained, leading to significant improvement of the electrochemical performances of VRB cells particularly under the high power operation. The corresponding energy efficiency is enhanced by 10.7 % under the operation of high charge/discharge current density (150 mA•cm-2) owing to faster charge transfer as compared with that without catalysts. These results suggest that Nb2O5 based nanofibers-decorating GFs hold great promise as high-performance electrodes for VRB applications.

  11. Capacity Decay Mechanism of Microporous Separator?Based All?Vanadium Redox Flow Batteries and its Recovery

    SciTech Connect (OSTI)

    Li, Bin; Luo, Qingtao; Wei, Xiaoliang; Nie, Zimin; Thomsen, Edwin C.; Chen, Baowei; Sprenkle, Vincent L.; Wang, Wei

    2014-02-01T23:59:59.000Z

    For all vanadium redox flow batteries (VRBs) with porous separators as membranes, convection effect is found to play a dominant role in the capacity decay of the cells over cycling by investigating the relationship between electrical performances and electrolyte compositions at both positive and negative sides. Although the concentration of total vanadium ions hardly changes at both sides over cycling, the net transfer of solutions from one side to another and thus asymmetrical valance of vanadium ions at both sides lead to the capacity fading and lower energy efficiency, which is confirmed to result from the hydraulic pressure differential at both sides of separators. In this paper, the hydraulic pressures of solutions at both sides can be in-situ monitored, and regulated by varying the gas pressures in electrolyte tanks. It is found that the capacity can be stabilized and the net transfer of solutions can be prevented by slightly tailoring the hydraulic pressure differential at both sides of separators, which, however, doesn’t work for Nafion membranes, suggesting the negligible convection factor in flow cells using Nafion membranes. Therefore, the possibility of porous separators allows long-term running for VRBs without capacity loss, highlighting a new pathway to develop membranes used in VRBs.

  12. all-vanadium redox flow: Topics by E-print Network

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

    Waters Outline: 1. Redox chemistry 2. Redox potential in aquatic systems 3. Eutrophication 4. Water treatment 1. Redox chemistry 15; Principle of equilibration of chemical...

  13. Resolving Losses at the Negative Electrode in All-Vanadium Redox Flow Batteries Using Electrochemical Impedance Spectroscopy

    SciTech Connect (OSTI)

    Sun, Che Nan [ORNL] [ORNL; Delnick, Frank M [ORNL] [ORNL; Aaron, D [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Mench, Matthew M [ORNL] [ORNL; Zawodzinski, Thomas A [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    We present an in situ electrochemical technique for the quantitative measurement and resolution of the ohmic, charge transfer and diffusion overvoltages at the negative electrode of an all-vanadium redox flow battery (VRFB) using electrochemical impedance spectroscopy (EIS). The mathematics describing the complex impedance of the V+2/V+3 redox reaction is derived and matches the experimental data. The voltage losses contributed by each process have been resolved and quantified at various flow rates and electrode thicknesses as a function of current density during anodic and cathodic polarization. The diffusion overvoltage was affected strongly by flow rate while the charge transfer and ohmic losses were invariant. On the other hand, adopting a thicker electrode significantly changed both the charge transfer and diffusion losses due to increased surface area. Furthermore, the Tafel plot obtained from the impedance resolved charge transfer overvoltage yielded the geometric exchange current density, anodic and cathodic Tafel slopes (135 5 and 121 5 mV/decade respectively) and corresponding transfer coefficients = 0.45 0.02 and = 0.50 0.02 in an operating cell.

  14. Bismuth Nanoparticle Decorating Graphite Felt as a High-Performance Electrode for an All-Vanadium Redox Flow Battery

    SciTech Connect (OSTI)

    Li, Bin; Gu, Meng; Nie, Zimin; Shao, Yuyan; Luo, Qingtao; Wei, Xiaoliang; Li, Xiaolin; Xiao, Jie; Wang, Chong M.; Sprenkle, Vincent L.; Wang, Wei

    2013-02-04T23:59:59.000Z

    The selection of electrode materials plays a great role in improving performances of all vanadium redox flow batteries (VRBs). Low-cost graphite felt (GF) as traditional electrode material has to be modified to address its issue of low electrocatalytic activity. In our paper, low-cost and highly conductive bismuth nanoparticles, as a powerful alternative electrocatalyst to noble metal, are proposed and synchronously electro-deposited onto the surface of GF while running flow cells employing the electrolytes containing suitable Bi3+. Although bismuth is proved to only take effect on the redox reaction of V(II)/V(III) and present at negative half-cell side, the whole cell electrochemical performances are significantly improved. In particular, the energy efficiency is increased by 11% owing to faster charge transfer as compared with one without Bi at high charge/discharge rate of 150 mA/cm2, which is prone to reduce stack size, thus dramatically reducing the cost. The excellent results show great promise of Bi nano-catalysts in the commercialization of VRBs in terms of product cost as well as electrochemical properties.

  15. Nuclear Magnetic Resonance Studies on Vanadium(IV) Electrolyte...

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

    Magnetic Resonance Studies on Vanadium(IV) Electrolyte Solutions for Vanadium Redox Flow Battery . Nuclear Magnetic Resonance Studies on Vanadium(IV) Electrolyte Solutions for...

  16. Short communication All-vanadium redox photoelectrochemical cell: An approach to store

    E-Print Network [OSTI]

    Liu, Fuqiang

    rechargeable batteries [8,9] in PEC energy storage, integrating a hydrogen bromine-embedded Si system and fuel demonstrated combin- ing PEC energy storage with a vanadium redox-flow battery (VRB), a well commercialized demonstrated facile photo- oxidation kinetics of VO2+ by a wide-band-gap TiO2 photoanode, presenting

  17. Redox Flow Batteries, a Review

    SciTech Connect (OSTI)

    U. Tennessee Knoxville; U. Texas Austin; McGill U; Weber, Adam Z.; Mench, Matthew M.; Meyers, Jeremy P.; Ross, Philip N.; Gostick, Jeffrey T.; Liu, Qinghua

    2011-07-15T23:59:59.000Z

    Redox flow batteries are enjoying a renaissance due to their ability to store large amounts of electrical energy relatively cheaply and efficiently. In this review, we examine the components of redox flow batteries with a focus on understanding the underlying physical processes. The various transport and kinetic phenomena are discussed along with the most common redox couples.

  18. Elucidating the Higher Stability of Vanadium (V) Cations in Mixed...

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

    Elucidating the Higher Stability of Vanadium (V) Cations in Mixed Acid Based Redox Flow Battery Electrolytes. Abstract: The Vanadium (V) cation structures in mixed acid based...

  19. Vanadium and Chromium Redox Behavior in borosilicate Nuclear Waste Glasses

    SciTech Connect (OSTI)

    D McKeown; I Muller; H Gan; Z Feng; C Viragh; I Pegg

    2011-12-31T23:59:59.000Z

    X-ray absorption spectroscopy (XAS) was used to characterize vanadium (V) and chromium (Cr) environments in low activity nuclear waste (LAW) glasses synthesized under a variety of redox conditions. V{sub 2}O{sub 5} was added to the melt to improve sulfur incorporation from the waste; however, at sufficiently high concentrations, V increased melt foaming, which lowered melt processing rates. Foaming may be reduced by varying the redox conditions of the melt, while small amounts of Cr are added to reduce melter refractory corrosion. Three parent glasses were studied, where CO-CO{sub 2} mixtures were bubbled through the corresponding melt for increasing time intervals so that a series of redox-adjusted-glasses was synthesized from each parent glass. XAS data indicated that V and Cr behaviors are significantly different in these glasses with respect to the cumulative gas bubbling times: V{sup 4+}/V{sub total} ranges from 8 to 35%, while Cr{sup 3+}/Cr{sub total} can range from 15 to 100% and even to population distributions including Cr{sup 2+}. As Na-content decreased, V, and especially, Cr became more reduced, when comparing equivalent glasses within a series. The Na-poor glass series show possible redox coupling between V and Cr, where V{sup 4+} populations increase after initial bubbling, but as bubbling time increases, V{sup 4+} populations drop to near the level of the parent glass, while Cr becomes more reduced to the point of having increasing Cr{sup 2+} populations.

  20. Cost and Performance Model for Redox Flow Batteries

    SciTech Connect (OSTI)

    Viswanathan, Vilayanur V.; Crawford, Aladsair J.; Stephenson, David E.; Kim, Soowhan; Wang, Wei; Li, Bin; Coffey, Greg W.; Thomsen, Edwin C.; Graff, Gordon L.; Balducci, Patrick J.; Kintner-Meyer, Michael CW; Sprenkle, Vincent L.

    2014-02-01T23:59:59.000Z

    A cost model was developed for all vanadium and iron-vanadium redox flow batteries. Electrochemical performance modeling was done to estimate stack performance at various power densities as a function of state of charge. This was supplemented with a shunt current model and a pumping loss model to estimate actual system efficiency. The operating parameters such as power density, flow rates and design parameters such as electrode aspect ratio, electrolyte flow channel dimensions were adjusted to maximize efficiency and minimize capital costs. Detailed cost estimates were obtained from various vendors to calculate cost estimates for present, realistic and optimistic scenarios. The main drivers for cost reduction for various chemistries were identified as a function of the energy to power ratio of the storage system. Levelized cost analysis further guided suitability of various chemistries for different applications.

  1. Cascade redox flow battery systems

    DOE Patents [OSTI]

    Horne, Craig R.; Kinoshita, Kim; Hickey, Darren B.; Sha, Jay E.; Bose, Deepak

    2014-07-22T23:59:59.000Z

    A reduction/oxidation ("redox") flow battery system includes a series of electrochemical cells arranged in a cascade, whereby liquid electrolyte reacts in a first electrochemical cell (or group of cells) before being directed into a second cell (or group of cells) where it reacts before being directed to subsequent cells. The cascade includes 2 to n stages, each stage having one or more electrochemical cells. During a charge reaction, electrolyte entering a first stage will have a lower state-of-charge than electrolyte entering the nth stage. In some embodiments, cell components and/or characteristics may be configured based on a state-of-charge of electrolytes expected at each cascade stage. Such engineered cascades provide redox flow battery systems with higher energy efficiency over a broader range of current density than prior art arrangements.

  2. Electrochimica Acta 52 (2007) 49424946 High-performance microfluidic vanadium redox fuel cell

    E-Print Network [OSTI]

    Brolo, Alexandre G.

    2007-01-01T23:59:59.000Z

    vanadium redox fuel cell Erik Kjeanga,c, Brenton T. Proctora,c, Alexandre G. Brolob,c, David A. Harringtonb a new microfluidic fuel cell design with high-surface area porous carbon electrodes and high aspect-effective and rapid fabrication, and would be applicable to most microfluidic fuel cell architectures. © 2007 Elsevier

  3. Advanced Redox Flow Batteries for Stationary Electrical Energy Storage

    SciTech Connect (OSTI)

    Li, Liyu; Kim, Soowhan; Xia, Guanguang; Wang, Wei; Yang, Zhenguo

    2012-03-19T23:59:59.000Z

    This report describes the status of the advanced redox flow battery research being performed at Pacific Northwest National Laboratories for the U.S. Department of Energy’s Energy Storage Systems Program. The Quarter 1 of FY2012 Milestone was completed on time. The milestone entails completion of evaluation and optimization of single cell components for the two advanced redox flow battery electrolyte chemistries recently developed at the lab, the all vanadium (V) mixed acid and V-Fe mixed acid solutions. All the single cell components to be used in future kW-scale stacks have been identified and optimized in this quarter, which include solution electrolyte, membrane or separator; carbon felt electrode and bi-polar plate. Varied electrochemical, chemical and physical evaluations were carried out to assist the component screening and optimization. The mechanisms of the battery capacity fading behavior for the all vanadium redox flow and the Fe/V battery were discovered, which allowed us to optimize the related cell operation parameters and continuously operate the system for more than three months without any capacity decay.

  4. Redox flow batteries based on supporting solutions containing chloride

    DOE Patents [OSTI]

    Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Zhang, Jianlu; Chen, Baowei; Nie, Zimin; Xia, Guanguang

    2014-01-14T23:59:59.000Z

    Redox flow battery systems having a supporting solution that contains Cl.sup.- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO.sub.4.sup.2- and Cl.sup.- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V.sup.2+ and V.sup.3+ in a supporting solution and a catholyte having V.sup.4+ and V.sup.5+ in a supporting solution. The supporting solution can contain Cl.sup.- ions or a mixture of SO.sub.4.sup.2- and Cl.sup.- ions.

  5. Redox Flow Batteries: An Engineering Perspective

    SciTech Connect (OSTI)

    Chalamala, Babu R.; Soundappan, Thiagarajan; Fisher, Graham R.; Anstey, Mitchell A.; Viswanathan, Vilayanur V.; Perry, Mike L.

    2014-10-01T23:59:59.000Z

    Redox flow batteries are well suited to provide modular and scalable energy storage systems for a wide range of energy storage applications. In this paper, we review the development of redox flow battery technology including recent advances in new redox active materials and systems. We discuss cost, performance, and reliability metrics that are critical for deployment of large flow battery systems. The technology, while relatively young, has the potential for significant improvement through reduced materials costs, improved energy and power efficiency, and significant reduction in the overall system cost.

  6. High energy density redox flow device

    DOE Patents [OSTI]

    Chiang, Yet-Ming; Carter, W. Craig; Ho, Bryan Y; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13T23:59:59.000Z

    Redox flow devices are described in which at least one of the positive electrode or negative electrode-active materials is a semi-solid or is a condensed ion-storing electroactive material, and in which at least one of the electrode-active materials is transported to and from an assembly at which the electrochemical reaction occurs, producing electrical energy. The electronic conductivity of the semi-solid is increased by the addition of conductive particles to suspensions and/or via the surface modification of the solid in semi-solids (e.g., by coating the solid with a more electron conductive coating material to increase the power of the device). High energy density and high power redox flow devices are disclosed. The redox flow devices described herein can also include one or more inventive design features. In addition, inventive chemistries for use in redox flow devices are also described.

  7. Rebalancing electrolytes in redox flow battery systems

    DOE Patents [OSTI]

    Chang, On Kok; Pham, Ai Quoc

    2014-12-23T23:59:59.000Z

    Embodiments of redox flow battery rebalancing systems include a system for reacting an unbalanced flow battery electrolyte with a rebalance electrolyte in a first reaction cell. In some embodiments, the rebalance electrolyte may contain ferrous iron (Fe.sup.2+) which may be oxidized to ferric iron (Fe.sup.3+) in the first reaction cell. The reducing ability of the rebalance reactant may be restored in a second rebalance cell that is configured to reduce the ferric iron in the rebalance electrolyte back into ferrous iron through a reaction with metallic iron.

  8. Fe-V redox flow batteries

    DOE Patents [OSTI]

    Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Zhang, Jianlu; Chen, Baowei; Nie, Zimin; Xia, Guanguang

    2014-07-08T23:59:59.000Z

    A redox flow battery having a supporting solution that includes Cl.sup.- anions is characterized by an anolyte having V.sup.2+ and V.sup.3+ in the supporting solution, a catholyte having Fe.sup.2+ and Fe.sup.3+ in the supporting solution, and a membrane separating the anolyte and the catholyte. The anolyte and catholyte can have V cations and Fe cations, respectively, or the anolyte and catholyte can each contain both V and Fe cations in a mixture. Furthermore, the supporting solution can contain a mixture of SO.sub.4.sup.2- and Cl.sup.- anions.

  9. High energy density redox flow device

    DOE Patents [OSTI]

    Chiang, Yet-Ming; Carter, William Craig; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13T23:59:59.000Z

    Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

  10. Iron-sulfide redox flow batteries

    DOE Patents [OSTI]

    Xia, Guan-Guang; Yang, Zhenguo; Li, Liyu; Kim, Soowhan; Liu, Jun; Graff, Gordon L

    2013-12-17T23:59:59.000Z

    Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S.sup.2- and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.

  11. Fact Sheet: Vanadium Redox Flow Batteries (October 2012)

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed offOCHCO2: FinalOffers New Training on Energy ManagementAugustin2012) | Department ofFactTechnology

  12. Recent Progress in Redox Flow Battery Research and Development

    SciTech Connect (OSTI)

    Wang, Wei; Luo, Qingtao; Li, Bin; Wei, Xiaoliang; Li, Liyu; Yang, Zhenguo

    2013-02-20T23:59:59.000Z

    With the increase need to seamlessly integrate the renewable energy with the current grid which itself is evolving into a more intelligent, efficient, and capable electrical power system, it is envisioned that the energy storage system will play a more prominent role in bridging the gap between the current technology and a clean sustainable future in grid reliability and utilization. Redox flow battery technology is leading the way in this perspective in providing a well balanced approach for current challenges. Recent progress in the research and development of redox flow battery technology is reviewed here with a focus on new chemistries and systems.

  13. Anthraquinone with Tailored Structure for Nonaqueous Metal-Organic Redox Flow Battery

    SciTech Connect (OSTI)

    Wang, Wei; Xu, Wu; Cosimbescu, Lelia; Choi, Daiwon; Li, Liyu; Yang, Zhenguo

    2012-06-08T23:59:59.000Z

    A nonaqueous, hybrid metal-organic redox flow battery based on tailored anthraquinone structure is demonstrated to have an energy efficiency of {approx}82% and a specific discharge energy density similar to aqueous redox flow batteries, which is due to the significantly improved solubility of anthraquinone in supporting electrolytes.

  14. Electrochemical investigation of polyhalide ion oxidation-reduction on carbon nanotube electrodes for redox flow batteries

    SciTech Connect (OSTI)

    Shao, Yuyan; Engelhard, Mark H.; Lin, Yuehe

    2009-10-01T23:59:59.000Z

    Polyhalide ions (Br-/BrCl2-) are an important redox couple for redox flow batteries. The oxidation-reduction behavior of polyhalide ions on a carbon nanotube (CNT) electrode has been investigated with cyclic voltammetry and electrochemical impedance spectroscopy. The onset oxidation potential of Br-/BrCl2- is negatively shifted by >100 mV, and the redox current peaks are greatly enhanced on a CNT electrode compared with that on the most widely-used graphite electrode. The reaction resistance of the redox couple (Br-/BrCl2-) is decreased on a CNT electrode. The redox reversibility is increased on a CNT electrode even though it still needs further improvement. CNT is a promising electrode material for redox flow batteries.

  15. TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries

    SciTech Connect (OSTI)

    Wei, Xiaoliang; Xu, Wu; Vijayakumar, M.; Cosimbescu, Lelia; Liu, Tianbiao L.; Sprenkle, Vincent L.; Wang, Wei

    2014-12-03T23:59:59.000Z

    We will present a novel design lithium-organic non-aqueous redox flow battery based on a TEMPO catholyte. This RFB produced desired electrochemical performance exceeding most of the currently reported nonaqueous RFB systems.

  16. Towards High-Performance Nonaqueous Redox Flow Electrolyte through Ionic Modification of Active Species

    SciTech Connect (OSTI)

    Wei, Xiaoliang; Cosimbescu, Lelia; Xu, Wu; Hu, Jian Z.; Vijayakumar, M.; Feng, Ju; Hu, Mary Y.; Deng, Xuchu; Xiao, Jie; Liu, Jun; Sprenkle, Vincent L.; Wang, Wei

    2015-01-01T23:59:59.000Z

    We will present a novel design lithium-organic non-aqueous redox flow battery based on a modified ferrocene catholyte. This RFB produced desired electrochemical performance exceeding most of the currently reported nonaqueous RFB systems.

  17. Vanadium redox-flow batteries Installation at Ris for characterisation measurements

    E-Print Network [OSTI]

    and investigating distributed power systems. SYSLAB consists of two wind turbines, a pv-array, a diesel genset it provides different services to grid including smoothing of wind turbine output, load balancing and similar in August 2007. Power systems with high penetration of Wind energy/Renewable energy Renewable energy

  18. all-uranium redox flow: Topics by E-print Network

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

    Waters Outline: 1. Redox chemistry 2. Redox potential in aquatic systems 3. Eutrophication 4. Water treatment 1. Redox chemistry 15; Principle of equilibration of chemical...

  19. Membrane Separator for Redox Flow Batteries that Utilize Anion Radical Mediators.

    SciTech Connect (OSTI)

    Delnick, Frank M.

    2014-10-01T23:59:59.000Z

    A Na + ion conducting polyethylene oxide membrane is developed for an organic electrolyte redox flow battery that utilizes anion radical mediators. To achieve high specific ionic conductivity, tetraethyleneglycol dimethylether (TEGDME) is used as a plasticizer to reduce crystallinity and increase the free volume of the gel film. This membrane is physically and chemically stable in TEGDME electrolyte that contains highly reactive biphenyl anion radical mediators.

  20. Proton Gradient Regulation 5-Mediated Cyclic Electron Flow under ATP-or Redox-Limited Conditions: A Study of

    E-Print Network [OSTI]

    Proton Gradient Regulation 5-Mediated Cyclic Electron Flow under ATP- or Redox-Limited Conditions.K.N.) The Chlamydomonas reinhardtii proton gradient regulation5 (Crpgr5) mutant shows phenotypic and functional traits discriminate two pathways for CEF and determine their maximum electron flow rates. The PGR5/proton gradient

  1. Optimization of electrode characteristics for the Br?/H? redox flow cell

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Van Nguyen, Trung

    2015-01-01T23:59:59.000Z

    The Br?/H? redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (–) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (–) catalyst layer on the membrane instead of on the carbon-paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm-2 and a peak power density of 1.4 W cm-2. Maximum energy efficiencymore »of 79% is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt (–) electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.« less

  2. Optimization of electrode characteristics for the Br2/H2 redox flow cell

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Nguyen, Trung V.

    2014-10-01T23:59:59.000Z

    The Br2/H2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (?) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (?) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm?2 and a peak power density of 1.4 W cm?2. Maximum energymore »efficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt (?) electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.« less

  3. Optimization of electrode characteristics for the Br2/H2 redox flow cell

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Nguyen, Trung V.

    2014-10-01T23:59:59.000Z

    The Br2/H2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (?) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (?) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm?2 and a peak power density of 1.4 W cm?2. Maximum energy efficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt (?) electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.

  4. TEMPO-based Catholyte for High Energy Density Nonaqueous Redox...

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

    TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries. TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries. Abstract: We will...

  5. Progress in Grid Scale Flow Batteries

    E-Print Network [OSTI]

    2011Year #12;Flow Battery Research at PNNL and Sandia #12 with industries and universities New Generation Redox Flow Batteries, PNNL Developed new generation redox flow

  6. Facile synthesized nanorod structured vanadium pentoxide for...

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

    synthesized nanorod structured vanadium pentoxide for high-rate lithium batteries. Facile synthesized nanorod structured vanadium pentoxide for high-rate lithium batteries....

  7. What's Next for Vanadium Dioxide?

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

    National Laboratory (ORNL) has made an important advancement in understanding a classic transition-metal oxide, vanadium dioxide, by quantifying the thermodynamic forces driving...

  8. City of Painesville, Ohio Vanadium Redox Battery Demonstration Program

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1. Feedstock &EnergyDepartmentCity of Los Angeles

  9. Fact Sheet: Vanadium Redox Battery Demonstration Program (August 2013) |

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011 Strategic Plan| Department of.pdf6-OPAMDepartment6 FY Fact

  10. Fact Sheet: Vanadium Redox Battery Demonstration Program (August 2013) |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport in RepresentativeDepartment ofDepartmentLastSodium-BetaDepartment of Energy

  11. Spectroscopic Investigations of the Fouling Process on Nafion...

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

    Redox Flow Batteries. Abstract: The Nafion-117 membrane used in vanadium redox flow battery (VRFB) is analyzed by X-ray photoelectron spectroscopy (XPS) and nuclear magnetic...

  12. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01T23:59:59.000Z

    P. C. Butler, "Advanced Batteries for Electric Vehicles andIntroduction," in Hnadbook of Batteries, 3rd Edition, D.T. B. Reddy, Handbook of Batteries, 2002). [67] R. Zito, US

  13. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01T23:59:59.000Z

    or novel hydrogen-storage materials are is needed. Althoughof storage tank volume, and thus hydrogen compression

  14. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01T23:59:59.000Z

    battery configuration. Lead-acid batteries do not shuttleincluding lead-acid, nickel-based, and lithium-ion batteries

  15. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01T23:59:59.000Z

    DC, 2008). "Energy Storage Technology Valuation Primer:storage technologies and does not require specific geographical siting, as pumped hydroelectric and compressed-air energyenergy. There are some technologies that enable practical storage

  16. Effects of additives on the stability of electrolytes for all...

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

    Effects of additives on the stability of electrolytes for all-vanadium redox flow batteries. Effects of additives on the stability of electrolytes for all-vanadium redox flow...

  17. Method for preparing high purity vanadium

    SciTech Connect (OSTI)

    Schmidt, F.; Carlson, O.N.

    1986-09-09T23:59:59.000Z

    A method is described of preparing high-purity, low-silicon vanadium metal from vanadium pentoxide containing silicon, iron and other impurities comprising: mixing the vanadium pentoxide with aluminum to form a reaction mixture, the quantity of aluminum in the mixture being from about stoichiometric to about 10% deficient in the amount necessary to completely reduce the vanadium pentoxide to vanadium metal: heating the mixture under reducing conditions to a temperature sufficient to react the mixture to reduce the vanadium pentoxide and form a vanadium-aluminum alloy containing silicon, iron and from about 0.6 to about 3 weight percent oxygen; heating the alloy under reduced pressure to a temperature sufficient to vaporize the aluminum and iron in the alloy and to react the silicon with some of the oxygen to form volatile silicon monoxide which vaporizes away from the alloy thereby removing aluminum, iron, silicon and some of the oxygen from the vanadium metal, and heating the vanadium metal in the presence of calcium metal to a temperature and for a period of time sufficient for the oxygen to diffuse from the vanadium and react with the calcium to form calcium oxide, thereby removing oxygen from the vanadium metal, forming a high-purity, low-silicon vanadium metal.

  18. Final Report - Crystal Settling, Redox, and High Temperature Properties of ORP HLW and LAW Glasses, VSL-09R1510-1, Rev. 0, dated 6/18/09

    SciTech Connect (OSTI)

    Kruger, Albert A.; Wang, C.; Gan, H.; Pegg, I. L.; Chaudhuri, M.; Kot, W.; Feng, Z.; Viragh, C.; McKeown, D. A.; Joseph, I.; Muller, I. S.; Cecil, R.; Zhao, W.

    2013-11-13T23:59:59.000Z

    The radioactive tank waste treatment programs at the U. S. Department of Energy (DOE) have featured joule heated ceramic melter technology for the vitrification of high level waste (HLW). The Hanford Tank Waste Treatment and Immobilization Plant (WTP) employs this same basic technology not only for the vitrification of HLW streams but also for the vitrification of Low Activity Waste (LAW) streams. Because of the much greater throughput rates required of the WTP as compared to the vitrification facilities at the West Valley Demonstration Project (WVDP) or the Defense Waste Processing Facility (DWPF), the WTP employs advanced joule heated melters with forced mixing of the glass pool (bubblers) to improve heat and mass transport and increase melting rates. However, for both HLW and LAW treatment, the ability to increase waste loadings offers the potential to significantly reduce the amount of glass that must be produced and disposed and, therefore, the overall project costs. This report presents the results from a study to investigate several glass property issues related to WTP HLW and LAW vitrification: crystal formation and settling in selected HLW glasses; redox behavior of vanadium and chromium in selected LAW glasses; and key high temperature thermal properties of representative HLW and LAW glasses. The work was conducted according to Test Plans that were prepared for the HLW and LAW scope, respectively. One part of this work thus addresses some of the possible detrimental effects due to considerably higher crystal content in waste glass melts and, in particular, the impact of high crystal contents on the flow property of the glass melt and the settling rate of representative crystalline phases in an environment similar to that of an idling glass melter. Characterization of vanadium redox shifts in representative WTP LAW glasses is the second focal point of this work. The third part of this work focused on key high temperature thermal properties of representative WTP HLW and LAW glasses over a wide range of temperatures, from the melter operating temperature to the glass transition.

  19. Synthesis of Nanodispersed Oxides of Vanadium, Titanium, Molybdenum...

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

    Nanodispersed Oxides of Vanadium, Titanium, Molybdenum, and Tungsten on Mesoporous Silica using Atomic Layer Synthesis of Nanodispersed Oxides of Vanadium, Titanium, Molybdenum,...

  20. Preparation of high purity vanadium

    SciTech Connect (OSTI)

    Carlson, O.N.; Burkholder, H.R.; Martsching, G.A.; Schmidt, F.A.

    1981-01-01T23:59:59.000Z

    The paper reviews the various reduction and refining methods that have been used to prepare vanadium metal. Earlier work on metallothermic and carbothermic reduction processes is discussed. Recent work on improving the scaling up the aluminothermic reduction process is described in detail. Iron and silicon are first removed from commercial V/sub 2/O/sub 5/ by an ion exchange separation technique and the purified oxide is then exothermically reduced with aluminum metal. The resulting V-Al ingot is heated in a vacuum to 1700/sup 0/C to remove the aluminum and dissolved oxygen, and the sponge is then electron-beam melted to remove residual volatile impurities to yield vanadium metal of 99.98% purity. Precautions taken during each processing stage to minimize carbon, nitrogen and oxygen contamination are described. Metal containing < 50 ppmw each of C, N and O, < 20 ppmw Si, and < 10 ppmw of Fe and Al has been prepared in kilogram quantities by this method. The hardness of the beam melted is 60 to 70 DPH. Experiments designed to scale up the reduction process and to increase the efficiency of the separation and melting steps are described. Various refining techniques that have been applied to the preparation of high purity vanadium are described and comparisons made between the quality of metal obtained by each.

  1. High power density self-cooled lithium-vanadium blanket.

    SciTech Connect (OSTI)

    Gohar, Y.; Majumdar, S.; Smith, D.

    1999-07-01T23:59:59.000Z

    A self-cooled lithium-vanadium blanket concept capable of operating with 2 MW/m{sup 2} surface heat flux and 10 MW/m{sup 2} neutron wall loading has been developed. The blanket has liquid lithium as the tritium breeder and the coolant to alleviate issues of coolant breeder compatibility and reactivity. Vanadium alloy (V-4Cr-4Ti) is used as the structural material because it can accommodate high heat loads. Also, it has good mechanical properties at high temperatures, high neutron fluence capability, low degradation under neutron irradiation, good compatibility with the blanket materials, low decay heat, low waste disposal rating, and adequate strength to accommodate the electromagnetic loads during plasma disruption events. Self-healing electrical insulator (CaO) is utilized to reduce the MHD pressure drop. A poloidal coolant flow with high velocity at the first wall is used to reduce the peak temperature of the vanadium structure and to accommodate high surface heat flux. The blanket has a simple blanket configuration and low coolant pressure to reduce the fabrication cost, to improve the blanket reliability, and to increase confidence in the blanket performance. Spectral shifter, moderator, and reflector are utilized to improve the blanket shielding capability and energy multiplication, and to reduce the radial blanket thickness. Natural lithium is used to avoid extra cost related to the lithium enrichment process.

  2. Vanadium catalysts break down biomass for fuels

    E-Print Network [OSTI]

    - 1 - Vanadium catalysts break down biomass for fuels March 26, 2012 Vanadium catalysts break down biomass into useful components Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is an attractive alternative as a feedstock for the production of renewable chemicals and fuels. The Department

  3. Vanadium hydride deuterium-tritium generator

    DOE Patents [OSTI]

    Christensen, Leslie D. (Livermore, CA)

    1982-01-01T23:59:59.000Z

    A pressure controlled vanadium hydride gas generator to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  4. Methods for making lithium vanadium oxide electrode materials

    DOE Patents [OSTI]

    Schutts, Scott M. (Menomonie, WI); Kinney, Robert J. (Woodbury, MN)

    2000-01-01T23:59:59.000Z

    A method of making vanadium oxide formulations is presented. In one method of preparing lithium vanadium oxide for use as an electrode material, the method involves: admixing a particulate form of a lithium compound and a particulate form of a vanadium compound; jet milling the particulate admixture of the lithium and vanadium compounds; and heating the jet milled particulate admixture at a temperature below the melting temperature of the admixture to form lithium vanadium oxide.

  5. Method for preparing high purity vanadium

    DOE Patents [OSTI]

    Schmidt, Frederick (Ames, IA); Carlson, O. Norman (Ames, IA)

    1986-09-09T23:59:59.000Z

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  6. Method for preparing high purity vanadium

    DOE Patents [OSTI]

    Schmidt, F.; Carlson, O.N.

    1984-05-16T23:59:59.000Z

    A method for preparing high purity vanadium having a low silicon content has been developed. Vanadium pentoxide is reduced with a stoichiometric, or slightly deficient amount of aluminum to produce a vanadium-aluminum alloy containing an excess of oxygen. Silicon is removed by electron-beam melting the alloy under oxidizing conditions to promote the formation of SiO which is volatile at elevated temperatures. Excess oxygen is removed by heating the alloy in the presence of calcium metal to form calcium oxide.

  7. Sampling, preservation, and analytical methods research plan - liquid redox sulfur recovery technologies: Stretford process. Topical report

    SciTech Connect (OSTI)

    Trofe, T.W.

    1986-11-01T23:59:59.000Z

    GRI has developed a sampling, preservation, and analytical (SPandA) methods research plan for developing and validating analytical methodologies for liquid redox sulfur recovery processes (e.g., Stretford process). The document describes the technical approach which will be used to direct research activities to develop SPandA methodologies to analyze gaseous, aqueous, and solid process streams from the Stretford sulfur recovery process. The primary emphasis is on developing and validating methodologies for analyzing vanadium (IV) and vanadium (V), anthraquinone disulphonic acids (ADA), polysulfide-sulfur, sulfide-sulfur, thiosulfate, sulfate, thiocyanate, total soluble sulfur, alkalinity, pH, total dissolved solids, total suspended solids, and dissolved oxygen in aqueous process streams. The document includes descriptions of the process streams and chemical species, selection of candidate analytical methods, and technical approach for methods development and validation.

  8. Paper Offer #: 031CES-216 PlanarArray REDOX Cells and pH Sensors

    E-Print Network [OSTI]

    Kounaves, Samuel P.

    in a see- into, flow-through polycarbonate chamber. A water-tight seal is obtained by using O-rings placed], conductivity sensors [3], REDOX cells [3], and pH sensors. This paper focuses on the development of nine REDOX cells, a conductivity sensor, a temperature #12;attached to the polycarbonatechamber

  9. Electrochemical Characterization of Vanadium Oxide Nanostructured Electrode

    E-Print Network [OSTI]

    Sadoway, Donald Robert

    microstructures called aerogels in the case of supercritical or freeze-drying and ambigels in the case of solvent for intercalated ions.7 When cycled between 4.0 and 1.5 V, vanadium oxide aerogels achieved capaci- ties of 410 mAh/g at C/40.6 Baudrin et al. have used the vanadium oxide aerogel structure to access a metastable phase

  10. Vanadium hydride deuterium-tritium generator

    DOE Patents [OSTI]

    Christensen, L.D.

    1980-03-13T23:59:59.000Z

    A pressure controlled vanadium hydride gas generator was designed to provide deuterium-tritium gas in a series of pressure increments. A high pressure chamber filled with vanadium-deuterium-tritium hydride is surrounded by a heater which controls the hydride temperature. The heater is actuated by a power controller which responds to the difference signal between the actual pressure signal and a programmed pressure signal.

  11. Manufacturing development of low activation vanadium alloys

    SciTech Connect (OSTI)

    Smith, J.P.; Johnson, W.R.; Baxi, C.B.

    1996-10-01T23:59:59.000Z

    General Atomics is developing manufacturing methods for vanadium alloys as part of a program to encourage the development of low activation alloys for fusion use. The culmination of the program is the fabrication and installation of a vanadium alloy structure in the DIII-D tokamak as part of the Radiative Divertor modification. Water-cooled vanadium alloy components will comprise a portion of the new upper divertor structure. The first step, procuring the material for this program has been completed. The largest heat of vanadium alloy made to date, 1200 kg of V-4Cr-4Ti, has been produced and is being converted into various product forms. Results of many tests on the material during the manufacturing process are reported. Research into potential fabrication methods has been and continues to be performed along with the assessment of manufacturing processes particularly in the area of joining. Joining of vanadium alloys has been identified as the most critical fabrication issue for their use in the Radiative Divertor Program. Joining processes under evaluation include resistance seam, electrodischarge (stud), friction and electron beam welding. Results of welding tests are reported. Metallography and mechanical tests are used to evaluate the weld samples. The need for a protective atmosphere during different welding processes is also being determined. General Atomics has also designed, manufactured, and will be testing a helium-cooled, high heat flux component to assess the use of helium cooled vanadium alloy components for advanced tokamak systems. The component is made from vanadium alloy tubing, machined to enhance the heat transfer characteristics, and joined to end flanges to allow connection to the helium supply. Results are reported.

  12. ORIGINAL PAPER Redox flow batteries: a review

    E-Print Network [OSTI]

    Mench, Matthew M.

    conducting phase O Oxidant R Reductant 1 Introduction Renewable-energy sources, such as solar and wind · Philip N. Ross · Jeffrey T. Gostick · Qinghua Liu Received: 12 July 2011 / Accepted: 16 August 2011 Ó batteries (RFBs) are enjoying a renaissance due to their ability to store large amounts of electrical energy

  13. Redox Flow Batteries - Energy Innovation Portal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection RadiationRecord-SettingHead of Contracting Activity (HCA)Storage

  14. Redox shuttle additives for overcharge protection in lithium batteries

    E-Print Network [OSTI]

    Richardson, Thomas J.; Ross Jr., P.N.

    1999-01-01T23:59:59.000Z

    No. 5,763,119. “Redox Shuttle Additives for Overchargeprotection, electrolytes, additives, redox shuttleREDOX SHUTTLE ADDITIVES FOR OVERCHARGE PROTECTION IN LITHIUM

  15. Computation of the Redox and Protonation Properties of Quinones...

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

    Computation of the Redox and Protonation Properties of Quinones: Towards the Prediction of Redox Cycling Natural Products. Computation of the Redox and Protonation Properties of...

  16. Energy Storage for the Power Grid

    SciTech Connect (OSTI)

    Wang, Wei; Imhoff, Carl; Vaishnav, Dave

    2014-04-23T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid.

  17. Energy Storage for the Power Grid

    ScienceCinema (OSTI)

    Wang, Wei; Imhoff, Carl; Vaishnav, Dave

    2014-06-12T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid.

  18. Towards Understanding the Poor Thermal Stability of V5+ Electrolyte...

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

    the Poor Thermal Stability of V5+ Electrolyte Solution in Vanadium Redox Flow Batteries. Towards Understanding the Poor Thermal Stability of V5+ Electrolyte Solution in...

  19. NETL F 451.1/1-1, Categorical Exclusion Designation Form

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

    144 Granite Street, Worcester, MA Premium Power Distributed Energy Storage Demonstration for National Grid Install and operate 500 kW Vanadium Redox flow battery at Worcester, MA....

  20. Holme et al. Soil Redox Sensor Networks RADIO FREQUENCY ENABLED SOIL REDOX POTENTIAL

    E-Print Network [OSTI]

    Rubinstein, Benjamin

    Holme et al. Soil Redox Sensor Networks RADIO FREQUENCY ENABLED SOIL REDOX POTENTIAL SENSOR technologies that may be combined into a cost effective soil redox sensor network, discuss the merits of each as a component of said network, describe a prototype soil redox sensor network and perform basic laboratory

  1. Multiple Redox Modes in the Reversible Lithiation of High-Capacity, Peierls-Distorted Vanadium Sulfide

    E-Print Network [OSTI]

    Britto, Sylvia; Leskes, Michal; Hua, Xiao; Hébert, Claire-Alice; Shin, Hyeon Suk; Clarke, Simon; Borkiewicz, Olaf; Chapman, Karena W.; Seshadri, Ram; Cho, Jaephil; Grey, Clare P.

    2015-06-08T23:59:59.000Z

    via the internet at http://pubs.acs.org. REFERENCES (1) Mizushima, K., Jones, P. C., Wiseman. P. J., Goodenough, J. B. Mater. Res. Bull. 1980, 15, 783–789. (2) Dahn, J. R.; Zheng, T.; Liu, Y.; Xue, J. S. Science 1995, 270, 590–593. (3...

  2. Short communication Effect of vanadium redox species on photoelectrochemical behavior of TiO2

    E-Print Network [OSTI]

    Liu, Fuqiang

    . Alternative and sustainable energy sources such as solar, wind, tidal power, geothermal, hydroelectricity to 1 M. This finding might render this approach a very promising way of solar energy conversion are getting depleted. Among them, solar energy is considered to be the most reliable and inexhaustible source

  3. Partitioning of hydrogen in the vanadium-lithium-hydrogen system at elevated temperatures

    SciTech Connect (OSTI)

    Hull, A.B.; Chopra, O.K.; Loomis, B.A.; Smith, D.L.

    1988-09-01T23:59:59.000Z

    Equilibrium concentrations of hydrogen in vanadium-base alloys exposed to flowing lithium at temperatures from 350 to 550/degree/C in a forced-circulation loop were measured by residual gas analysis and the vacuum fusion method. Residual gas analysis and removal of material from the surface allowed a determination of the spatial hydrogen distribution in the alloys. These experimental results were compared with calculated thermodynamic distribution coefficients for hydrogen in the vanadium/lithium system. Small amounts of other solutes in the molten lithium and in the alloys affected the solubility, diffusivity, and resultant distribution of hydrogen. Thermodynamic calculations demonstrated the importance of major alloying elements to the partitioning of hydrogen. 12 refs., 5 figs., 2 tabs.

  4. Modified lithium vanadium oxide electrode materials products and methods

    DOE Patents [OSTI]

    Thackeray, Michael M. (Naperville, IL); Kahaian, Arthur J. (Chicago, IL); Visser, Donald R. (Naperville, IL); Dees, Dennis W. (Downers Grove, IL); Benedek, Roy (Western Springs, IL)

    1999-12-21T23:59:59.000Z

    A method of improving certain vanadium oxide formulations is presented. The method concerns fluorine doping formulations having a nominal formula of LiV.sub.3 O.sub.8. Preferred average formulations are provided wherein the average oxidation state of the vanadium is at least 4.6. Herein preferred fluorine doped vanadium oxide materials, electrodes using such materials, and batteries including at least one electrode therein comprising such materials are provided.

  5. Vanadium-pumped titanium x-ray laser

    DOE Patents [OSTI]

    Nilsen, J.

    1992-05-26T23:59:59.000Z

    A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

  6. VACUUM PUMPING STUDY OF TITANIUM-ZIRCONIUM-VANADIUM THIN FILMS*

    E-Print Network [OSTI]

    ERL 03-8 VACUUM PUMPING STUDY OF TITANIUM-ZIRCONIUM-VANADIUM THIN FILMS* Yulin Li# and Simon Ho high vacuum. As part of R&D efforts for the proposed Energy Recovery Linac at Cornell, the pumping performance of Titanium- Zirconium-Vanadium (TiZrV) NEG thin films was investigated to provide `engineering

  7. Redox Shuttle Additives | Argonne National Laboratory

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

    available for licensing: A series of novel redox shuttle additives for lithium-ion batteries Seven-technology suite helps reduce battery costs Provides overcharge...

  8. Anisotropic reactive ion etching of vanadium dioxide 

    E-Print Network [OSTI]

    Radle, Byron K

    1990-01-01T23:59:59.000Z

    Facility for Submicron Structures, Cornell University, Ithaca, New York [7]. In these studies thin film VO2 was etched with a SF6/CO2 chemistry. SF6 chemistry was chosen because volatile vanadium fluorides can be formed easily. CO2 supplied the carbon... (Silicon Doped GaAs) Semi-Insulating GaAs Metal (AuGe, Ni, Au) Fig. 19. This is a step by step drawn representation of the fabrication procedure. 53 1. Pattern Photo Resist for Optical Stack etch mask. P Etched VOz in CFe plasma. 3. Etched Alz...

  9. Vanadium catalysts break down biomass for fuels

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps toValidatingCloudPoissonVENIndustrialVanadium

  10. Patterns of vanadium accumulation in petroleum and natural bitumen

    SciTech Connect (OSTI)

    Gol'dberg, I.S.; Kaplan, Z.G.; Ponomarev, V.S.

    1986-06-01T23:59:59.000Z

    Vanadium is one of the most abundant metals in oils and natural bitumens, with concentrations ranging from 10/sup -2/ to 1.5 x 10/sup 3/ ppm in oils and to as much as 0.6% in bitumens. Vanadium contents in some oil and bitumen deposits are comparable with those of vanadium-bearing titanomagnetite ores. The authors have examined the distributions of vanadium and associated trace elements (Ni, Mo, Co, etc.) in oils and bitumens for the Volga-Ural and Timan-Pechora basins, which are petroleum-metallogenic provinces of the vanadium-nickel type. The vanadium and nickel concentrations in the oils and bitumens, in bulk and by fractions, have been determined, without ashing the samples, by X-ray fluorescence analysis using /sup 55/Fe and /sup 238/Pu radionuclides and a semiconductor spectrometer. The ash was examined by emission spectrography and X-ray structural methods. The data reveal regularities in the vanadium concentration related to the physicochemical parameters. The authors also used previously published analyses to extend the statistical sample. 16 references.

  11. Vanadium-base alloys for fusion reactor applications

    SciTech Connect (OSTI)

    Smith, D.L.; Loomis, B.A.; Diercks, D.R.

    1984-10-01T23:59:59.000Z

    Vanadium-base alloys offer potentially significant advantages over other candidate alloys as a structural material for fusion reactor first wall/blanket applications. Although the data base is more limited than that for the other leading candidate structural materials, viz., austenitic and ferritic steels, vanadium-base alloys exhibit several properties that make them particularly attractive for the fusion reactor environment. This paper presents a review of the structural material requirements, a summary of the materials data base for selected vanadium-base alloys, and a comparison of projected performance characteristics compared to other candidate alloys. Also, critical research and development (R and D) needs are defined.

  12. REVIEW ARTICLE Redox regulation of intercellular transport

    E-Print Network [OSTI]

    Jackson, David

    REVIEW ARTICLE Redox regulation of intercellular transport Yoselin Benitez-Alfonso & David Jackson research has suggested the participa- tion of ROS in the regulation of PD transport. The study of several in cell redox homeostasis and PD transport, and the histological detection of hydrogen peroxide

  13. Redox reactions of reduced flavin mononucleotide (FMN), riboflavin...

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

    Redox reactions of reduced flavin mononucleotide (FMN), riboflavin (RBF), and anthraquinone-2,6-disulfonate (AQDS) with Redox reactions of reduced flavin mononucleotide (FMN),...

  14. Enrichment of Functional Redox Reactive Proteins and Identification...

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

    Redox Reactive Proteins and Identification by Mass Spectrometry Results in Several Terminal Fe(III) Enrichment of Functional Redox Reactive Proteins and Identification by Mass...

  15. Novel Redox Shuttles for Overcharge Protection of Lithium-Ion...

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

    Redox Shuttles for Overcharge Protection of Lithium-Ion Batteries Technology available for licensing: Electrolytes containing novel redox shuttles (electron transporters) for...

  16. Redox Chemistry in Thin Layers of Organometallic Complexes Prepared...

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

    Redox Chemistry in Thin Layers of Organometallic Complexes Prepared Using Ion Soft Landing. Redox Chemistry in Thin Layers of Organometallic Complexes Prepared Using Ion Soft...

  17. Method to remove uranium/vanadium contamination from groundwater

    DOE Patents [OSTI]

    Metzler, Donald R. (DeBeque, CO); Morrison, Stanley (Grand Junction, CO)

    2004-07-27T23:59:59.000Z

    A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

  18. Overview of the vanadium alloy researches for fusion reactors

    SciTech Connect (OSTI)

    Chen, J. M.; Chernov, V. M.; Kurtz, Richard J.; Muroga, Takeo

    2011-03-05T23:59:59.000Z

    Various vanadium alloys are being developed as one of the options of structural materials for advanced blankets of fusion reactors. Besides the large heats made in Japan and US, a 110 kg V-4Cr-4Ti ingot was produced in RF recently. Development of advanced vanadium alloys were also carried out, such as the ultra-fine grain alloys containing Y and that with W and TiC strengthening particles. Investigations were performed for further widening of temperature and mechanical application windows of the reference V-4Cr-4Ti alloy by plastic deformation and heat treatments. Neutron irradiation effects combined with lithium corrosion were studied. In addition, some efforts are oriented to issues related to DEMO blanket manufacturing technology, such as W coating for first wall protection and the welding technologies to fabricate large vanadium component. This paper highlights the recent activities of these vanadium alloy researches, discusses the critical issues and summarizes the remaining issues to be addressed.

  19. Layered Vanadium and Molybdenum Oxides: Batteries and Electrochromics

    SciTech Connect (OSTI)

    Chernova, N. A.; Roppolo, M.; Dillon, A. C.; Whittingham, M. S.

    2009-01-01T23:59:59.000Z

    The layered oxides of vanadium and molybdenum have been studied for close to 40 years as possible cathode materials for lithium batteries or electrochromic systems. The highly distorted metal octahedra naturally lead to the formation of a wide range of layer structures, which can intercalate lithium levels exceeding 300 Ah/kg. They have found continuing success in medical devices, such as pacemakers, but many challenges remain in their application in long-lived rechargeable devices. Their high-energy storage capability remains an encouragement to researchers to resolve the stability concerns of vanadium dissolution and the tendency of lithium and vanadium to mix changing the crystal structure on cycling the lithium in and out. Nanomorphologies have enabled higher reactivities to be obtained for both vanadium and molybdenum oxides, and with the latter show promise for electrochromic displays.

  20. Method to Remove Uranium/Vanadium Contamination from Groundwater

    DOE Patents [OSTI]

    Metzler, Donald R.; Morrison Stanley

    2004-07-27T23:59:59.000Z

    A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

  1. Redox polymer electrodes for advanced batteries

    DOE Patents [OSTI]

    Gregg, B.A.; Taylor, A.M.

    1998-11-24T23:59:59.000Z

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene. 2 figs.

  2. Redox polymer electrodes for advanced batteries

    DOE Patents [OSTI]

    Gregg, Brian A. (Golden, CO); Taylor, A. Michael (Golden, CO)

    1998-01-01T23:59:59.000Z

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene.

  3. Pollution of Natural Waters 1. Redox chemistry

    E-Print Network [OSTI]

    Schofield, Jeremy

    . Eutrophication 4. Water treatment 1. Redox chemistry #15; Principle of equilibration of chemical system R Keq;sh and other aquatic life { Shift to anaerobic metabolic mechanisms #15; Eutrophication: agin

  4. Microstructural effects on capacity-rate performance of vanadium oxide cathodes in lithium-ion batteries

    E-Print Network [OSTI]

    Davis, Robin M. (Robin Manes)

    2005-01-01T23:59:59.000Z

    Vanadium oxide thin film cathodes were analyzed to determine whether smaller average grain size and/or a narrower average grain size distribution affects the capacity-rate performance in lithium-ion batteries. Vanadium ...

  5. MICROSCALE METABOLIC, REDOX AND ABIOTIC REACTIONS IN HANFORD 300 AREA SUBSURFACE SEDIMENTS

    SciTech Connect (OSTI)

    Beyenal, Haluk [WSU] [WSU; McLEan, Jeff [JCVI] [JCVI; Majors, Paul [PNNL] [PNNL; Fredrickson, Jim [PNNL] [PNNL

    2013-11-14T23:59:59.000Z

    The Hanford 300 Area is a unique site due to periodic hydrologic influence of river water resulting in changes in groundwater elevation and flow direction. This area is also highly subject to uranium remobilization, the source of which is currently believed to be the region at the base of the vadose zone that is subject to period saturation due to the changes in the water levels in the Columbia River. We found that microbial processes and redox and abiotic reactions which operate at the microscale were critical to understanding factors controlling the macroscopic fate and transport of contaminants in the subsurface. The combined laboratory and field research showed how microscale conditions control uranium mobility and how biotic, abiotic and redox reactions relate to each other. Our findings extended the current knowledge to examine U(VI) reduction and immobilization using natural 300 Area communities as well as selected model organisms on redox-sensitive and redox-insensitive minerals. Using innovative techniques developed specifically to probe biogeochemical processes at the microscale, our research expanded our current understanding of the roles played by mineral surfaces, bacterial competition, and local biotic, abiotic and redox reaction rates on the reduction and immobilization of uranium.

  6. a-dependent redox biology: Topics by E-print Network

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

    Waters Outline: 1. Redox chemistry 2. Redox potential in aquatic systems 3. Eutrophication 4. Water treatment 1. Redox chemistry 15; Principle of equilibration of chemical...

  7. auto-protective redox buffering: Topics by E-print Network

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

    Waters Outline: 1. Redox chemistry 2. Redox potential in aquatic systems 3. Eutrophication 4. Water treatment 1. Redox chemistry 15; Principle of equilibration of chemical...

  8. Electroslag remelting of a vanadium alloy

    SciTech Connect (OSTI)

    Nafziger, R.H. [Bureau of Mines, Albany, OR (United States); Smolik, G.R.; Carmack, W.J. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1996-12-31T23:59:59.000Z

    The Bureau of Mines, in cooperation with the Idaho National Engineering Laboratory, has electroslag melted a V-5Ti-5Cr alloy using a fused CaF{sub 2} flux. The alloy is a candidate for use in future fusion reactors. One objective of this research was to evaluate the feasibility of the electroslag melting process in separating simulated radioactive isotopes from the V alloy to demonstrate recyclability. Small amounts of Ca, Y, and Mn were added as surrogates for radioactive isotopes. Results showed that this vanadium alloy can be electroslag melted satisfactorily. The impurities added intentionally were removed or decreased successfully. Among the major alloying constituents, Cr was retained but there were some Ti losses. The latter may be controlled with process refinements. This research suggests that the electroslag melting process could be a suitable method for recycling V alloys after use in future fusion reactors, or for processing other reactive metal alloys with more immediate applications. 3 refs., 1 fig., 5 tabs.

  9. Sorption preconcentration of vanadium for its determination in sea water

    SciTech Connect (OSTI)

    Andreeva, I.Yu.; Lebedeva, L.I.; Izotova, Yu.A.; Danilova, E.Ya.

    1987-08-10T23:59:59.000Z

    This work is devoted to a study of the conditions of vanadium sorption by a fibrous sorbent with a view to evolving a procedure for its determination in sea water. The sorbent was the same as used by them earlier for molybdenum preconcentration. It is a fiber based on polyethylenepolyamine-modified polyacrylonitrile. The sorbent contained 80% tertiary and approx. = 20% primary and secondary amino groups. Static exchange capacity of the sorbent relative to HCl 2 mmole/g, swelling 34%, fiber diameter 0.016 mm. The vanadium content was determined photometrically using acidic chromium blue K.

  10. Spectroscopy of vanadium (III) doped gallium lanthanum sulphide chalcogenide glass

    E-Print Network [OSTI]

    Hughes, M; Rutt, H; Hewak, D

    2014-01-01T23:59:59.000Z

    Vanadium doped gallium lanthanum sulphide glass (V:GLS) displays three absorption bands at 580, 730 and 1155 nm identified by photoluminescence excitation measurements. Broad photoluminescence, with a full width half maximum (FWHM) of 500 nm, is observed peaking at 1500 nm when exciting at 514, 808 and 1064 nm. The fluorescence lifetime and quantum efficiency at 300 K were measured to be 33.4 us and 4 % respectively. From the available spectroscopic data we propose the vanadium ions valence to be 3+ and be in tetrahedral coordination The results indicate potential for development of a laser or optical amplifier based on V:GLS.

  11. Investigation of redox processes at semiconductor electrode liquid junctions

    SciTech Connect (OSTI)

    Koval, C.A.

    1990-08-01T23:59:59.000Z

    Research in fundamental aspects of photoelectrochemical cells has been in the following areas: chemical probes for hot carrier processes, electrostatic theory for describing electrical interactions at interfaces, and kinetics of electron transfer at ideal semiconductor solution interfaces. Our goal is to achieve a better understanding of dark and photo-induced current flow at the semiconductor electrode/redox electrolyte interface (SEI) so that devices and processes utilizing this interface for solar energy conversion can be developed or improved. Our most important accomplishment has been the development of a redox system capable of detecting hot electrons at the p-InP/acetonitrile interface. Also, we have examined electrostatic theory for the image potential of an ion as a function of distance from the SEI. Finally, our group was one of the first to realize that the 2-dimensional metal chalcogenides (MC) are excellent materials for fundamental studies of electron transfer at the SEI. One of the chief potential advantages for use of MC's is the formation of semiconductor/liquid junctions with nearly ideal electrochemical properties. 27 refs., 1 fig.

  12. Redox, haem and CO in enzymatic catalysis and regulation

    E-Print Network [OSTI]

    Ragsdale, Stephen W.

    The present paper describes general principles of redox catalysis and redox regulation in two diverse systems. The first is microbial metabolism of CO by the Wood–Ljungdahl pathway, which involves the conversion of CO or ...

  13. Synthesis and Enhanced Intercalation Properties of Nanostructured Vanadium Oxides

    E-Print Network [OSTI]

    Cao, Guozhong

    intercalation properties of nanostructured vanadium oxides for energy storage as well as other applications-volume, and environment friendly energy storage/conversion devices are developed, and nanomaterials are attracting great-18 The nanostructured form of this material has been employed in FETs,19 sensors,20,21 spintronic devices,22

  14. Electrochemical kinetics of thin film vanadium pentoxide cathodes for lithium batteries

    E-Print Network [OSTI]

    Mui, Simon C., 1976-

    2005-01-01T23:59:59.000Z

    Electrochemical experiments were performed to investigate the processing-property-performance relations of thin film vanadium pentoxide cathodes used in lithium batteries. Variations in microstructures were achieved via ...

  15. Redox Shuttle Additives - Energy Innovation Portal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection RadiationRecord-SettingHead of Contracting ActivityRedox

  16. Temperature relationship of the elastic constants of vanadium

    SciTech Connect (OSTI)

    Belousov, O.K.

    1987-09-01T23:59:59.000Z

    Information on the elastic constants of vanadium and their temperature relationship is limited and ambiguous. This article gives the values of these characteristics for VEL-2 electron beam remelted vanadium with a purity of about 99.8%. The elastic properties were measured in heating from 20 to 1600/sup 0/C in a vacuum. The relationship of the modulus of elasticity to temperature has two almost linear portions in the 20-300 and 300-1350/sup 0/C ranges and then a more intense reduction in it is observed. The shear modulus drops sharply starting with 800/sup 0/C and decreases to G = 36 kN/mm/sup 2/ at 1600/sup 0/C. Poisson's ratio has values close to 0.3. Its most significant increase starts with 1400/sup 0/C.e

  17. This journal is c the Owner Societies 2013 Phys. Chem. Chem. Phys., 2013, 15, 10841--10848 10841 Cite this: Phys.Chem.Chem.Phys.,2013,

    E-Print Network [OSTI]

    Zhao, Tianshou

    of vanadium ions through the porous electrodes of vanadium redox flow batteries Qian Xu and T. S. Zhao flow batteries (VRFBs), unique experimental setups for electrochemically determining the two transport-level mass-transfer coefficient through the porous electrode made of graphite felt, a typical material

  18. Factors Controlling Redox Speciation of Plutonium and Neptunium in Extraction Separation Processes

    SciTech Connect (OSTI)

    Paulenova, Alena [Principal Investigator; Vandegrift, III, George F. [Collaborator

    2013-09-24T23:59:59.000Z

    The objective of the project was to examine the factors controlling redox speciation of plutonium and neptunium in UREX+ extraction in terms of redox potentials, redox mechanism, kinetics and thermodynamics. Researchers employed redox-speciation extractions schemes in parallel to the spectroscopic experiments. The resulting distribution of redox species w studied uring spectroscopic, electrochemical, and spectro-electrochemical methods. This work reulted in collection of data on redox stability and distribution of redox couples in the nitric acid/nitrate electrolyte and the development of redox buffers to stabilize the desired oxidation state of separated radionuclides. The effects of temperature and concentrations on the redox behavior of neptunium were evaluated.

  19. Investigation of Local Environments in Nafion-SiO2 Composite...

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

    of the analysis of the Nafion-SiO2 composite membrane used in a vanadium redox flow battery by nuclear magnetic resonance (NMR) spectroscopy, X-ray photoelectron spectroscopy...

  20. Influence of Iron Redox Transformations on Plutonium Sorption...

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

    and Pu(V) reduction demonstrates the potential impact of changing iron mineralogy on plutonium subsurface transport through redox transition areas. These findings...

  1. Redox shuttles for lithium ion batteries

    DOE Patents [OSTI]

    Weng, Wei; Zhang, Zhengcheng; Amine, Khalil

    2014-11-04T23:59:59.000Z

    Compounds may have general Formula IVA or IVB. ##STR00001## where, R.sup.8, R.sup.9, R.sup.10, and R.sup.11 are each independently selected from H, F, Cl, Br, CN, NO.sub.2, alkyl, haloalkyl, and alkoxy groups; X and Y are each independently O, S, N, or P; and Z' is a linkage between X and Y. Such compounds may be used as redox shuttles in electrolytes for use in electrochemical cells, batteries and electronic devices.

  2. Real-Time Redox Measurements during Endoplasmic Reticulum Stress Reveal

    E-Print Network [OSTI]

    Mullins, Dyche

    Real-Time Redox Measurements during Endoplasmic Reticulum Stress Reveal Interlinked Protein Folding.10.011 SUMMARY Disruption of protein folding in the endoplasmic reticulum (ER) causes unfolded proteins to accumu is active. Because ER redox po- tential is optimized for oxidative protein folding, we reasoned

  3. Redox Transformations and Transport of Cesium and Iodine

    E-Print Network [OSTI]

    isotopes of cesium (137 Cs) and iodine (131 I and 129 I) are environmental contaminants derived fromRedox Transformations and Transport of Cesium and Iodine (-1, 0, +5) in Oxidizing and Reducing, to study the redox chemistry (I) and transport (Cs, I) of cesium and iodine in a field setting. Injection

  4. Biogeochemical Redox Processes and their Impact on Contaminant Dynamics

    E-Print Network [OSTI]

    Sparks, Donald L.

    reactions via the oxidation of labile organic carbon or inorganic compounds (electron donors often controls the release or sequestration of inorganic contaminants. Redox processes control Thebiogeochemicalcyclesofmanymajorandtraceelements are driven by redox processes. Examples include the cycles of carbon (C), nitrogen (N), sulfur (S

  5. Kinetic model of whole-body vanadium metabolism: studies in sheep

    SciTech Connect (OSTI)

    Patterson, B.W.; Hansard, S.L. II; Ammerman, C.B.; Henry, P.R.; Zech, L.A.; Fisher, W.R.

    1986-08-01T23:59:59.000Z

    A compartmental model for vanadium metabolism in sheep has been proposed. The model is consistent with data obtained from sheep fed a control diet (2.6 ppm vanadium) containing 0 or 200 ppm supplemental vanadium. Sheep were administered UYV dioxovanadium either orally or intravenously. Blood feces, and urine radioactivity were monitored for 6 days postdosing. Several new insights regarding vanadium metabolism are suggested and tested against the data using the model. Some of these include 1) significant absorption of UYV occurs from the upper gastrointestinal tract; 2) an in vivo process is necessary in order for UYV dioxovanadium to be converted into a more biologically reactive species; 3) at steady state the upper and lower gastrointestinal tracts contain at least 10- and 100-fold more mass of vanadium, respectively, than does blood. No statistically significant differences in transport rate constants were found between animals receiving 0 and 200 ppm supplemental dietary vanadium. The availability of a model will enable the refinement of future studies regarding vanadium metabolism in the ruminant.

  6. Nitridation under ammonia of high surface area vanadium aerogels

    SciTech Connect (OSTI)

    Merdrignac-Conanec, Odile [Laboratoire Verres et Ceramiques, UMR CNRS 6512, Institut de Chimie de Rennes, Universite de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France)]. E-mail: odile.merdrignac@univ-rennes1.fr; El Badraoui, Khadija [Laboratoire Verres et Ceramiques, UMR CNRS 6512, Institut de Chimie de Rennes, Universite de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France); L'Haridon, Paul [Laboratoire Verres et Ceramiques, UMR CNRS 6512, Institut de Chimie de Rennes, Universite de Rennes 1, Campus de Beaulieu, F-35042 Rennes Cedex (France)

    2005-01-15T23:59:59.000Z

    Vanadium pentoxide gels have been obtained from decavanadic acid prepared by ion exchange on a resin from ammonium metavanadate solution. The progressive removal of water by solvent exchange in supercritical conditions led to the formation of high surface area V{sub 2}O{sub 5}, 1.6H{sub 2}O aerogels. Heat treatment under ammonia has been performed on these aerogels in the 450-900 deg. C temperature range. The oxide precursors and oxynitrides have been characterized by XRD, SEM, TGA, BET. Nitridation leads to divided oxynitride powders in which the fibrous structure of the aerogel is maintained. The use of both very low heating rates and high surface area aerogel precursors allows a higher rate and a lower threshold of nitridation than those reported in previous works. By adjusting the nitridation temperature, it has been possible to prepare oxynitrides with various nitrogen enrichment and vanadium valency states. Whatever the V(O,N) composition, the oxidation of the oxynitrides in air starts between 250 and 300 deg. C. This determines their potential use as chemical gas sensors at a maximum working temperature of 250 deg. C.

  7. Methane oxidation over dual redox catalysts

    SciTech Connect (OSTI)

    Klier, K.; Herman, R.G.; Sojka, Z.; DiCosimo, J.I.; DeTavernier, S.

    1992-06-01T23:59:59.000Z

    Catalytic oxidation of methane to partial oxidation products, primarily formaldehyde and C[sub 2] hydrocarbons, was found to be directed by the catalyst used. In this project, it was discovered that a moderate oxidative coupling catalyst for C[sub 2] hydrocarbons, zinc oxide, is modified by addition of small amounts of Cu and Fe dopants to yield fair yields of formaldehyde. A similar effect was observed with Cu/Sn/ZnO catalysts, and the presence of a redox Lewis acid, Fe[sup III] or Sn[sup IV], was found to be essential for the selectivity switch from C[sub 2] coupling products to formaldehyde. The principle of double doping with an oxygen activator (Cu) and the redox Lewis acid (Fe, Sn) was pursued further by synthesizing and testing the CuFe-ZSM-5 zeolite catalyst. The Cu[sup II](ion exchanged) Fe[sup III](framework)-ZSM-5 also displayed activity for formaldehyde synthesis, with space time yields exceeding 100 g/h-kg catalyst. However, the selectivity was low and earlier claims in the literature of selective oxidation of methane to methanol over CuFe-ZSM-5 were not reproduced. A new active and selective catalytic system (M=Sb,Bi,Sn)/SrO/La[sub 2]O[sub 3] has been discovered for potentially commercially attractive process for the conversion of methane to C[sub 2] hydrocarbons, (ii) a new principle has been demonstrated for selectivity switching from C[sub 2] hydrocarbon products to formaldehyde in methane oxidations over Cu,Fe-doped zinc oxide and ZSM-5, and (iii) a new approach has been initiated for using ultrafine metal dispersions for low temperature activation of methane for selective conversions. Item (iii) continues being supported by AMOCO while further developments related to items (i) and (ii) are the objective of our continued effort under the METC-AMOCO proposed joint program.

  8. Study to establish cost projections for production of redox chemicals

    SciTech Connect (OSTI)

    Walther, J.F.; Greco, C.C.; Rusinko, R.N.; Wadsworth, A.L. III

    1982-11-01T23:59:59.000Z

    A cost study of four proposed manufacturing processes for redox chemicals for the NASA REDOX Energy Storage System yielded favorable selling prices in the range $0.99 to $1.91/kg of chromic chloride, anhydrous basis, including ferrous chloride. The prices corresponded to specific energy storage costs from under $9 to $17/kWh. A refined and expanded cost analysis of the most favored process yielded a price estimate corresponding to a storage cost of $11/kWh. The findings supported the potential economic viability of the NASA REDOX system.

  9. Chemical vapour deposition of thermochromic vanadium dioxide thin films for energy efficient glazing

    SciTech Connect (OSTI)

    Warwick, Michael E.A. [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London, WC1H 0AJ (United Kingdom); UCL Energy Institute, Central House, 14 Upper Woburn Place, London, WC1H 0NN (United Kingdom); Binions, Russell, E-mail: r.binions@qmul.ac.uk [School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom)

    2014-06-01T23:59:59.000Z

    Vanadium dioxide is a thermochromic material that undergoes a semiconductor to metal transitions at a critical temperature of 68 °C. This phase change from a low temperature monoclinic structure to a higher temperature rutile structure is accompanied by a marked change in infrared reflectivity and change in resistivity. This ability to have a temperature-modulated film that can limit solar heat gain makes vanadium dioxide an ideal candidate for thermochromic energy efficient glazing. In this review we detail the current challenges to such glazing becoming a commercial reality and describe the key chemical vapour deposition technologies being employed in the latest research. - Graphical abstract: Schematic demonstration of the effect of thermochromic glazing on solar radiation (red arrow represents IR radiation, black arrow represents all other solar radiation). - Highlights: • Vanadium dioxide thin films for energy efficient glazing. • Reviews chemical vapour deposition techniques. • Latest results for thin film deposition for vanadium dioxide.

  10. Spectrophotometric determination of vanadium in metallurgical products with carminic acid and cetyltrimethylammonium chloride

    SciTech Connect (OSTI)

    Babenko, N.L.; Blokh, M. Sh.; Guseva, T.D.

    1985-11-01T23:59:59.000Z

    According to the authors, there is an increasing demand for sensitive, selective, and rapid methods of determining low levels of vanadium in metallurgical products, and solvent-extraction methods do not meet the requirements. The authors used an anthraquinone dye carminic acid (CA) as a chromophoric organic reagent: 1, 3, 4, 6-tetrahydroxy-2-R-5carboxy-8-methylanthra-9, 10-quinone. The CSA was cetyltrimethylammonium chloride CTA. The three-component system was examined in order to devise a reasonably sensitive and rapid method of determining vanadium in metallurgical products. A study is made of the complexing in the system formed by vanadium (IV) with CA and the CSA. The optimum conditions for the formation of the complex have been established together with the spectrophotometric characteristics. A spectrophotometric method has been devised for determining from 0.05 to 5% of vanadium in metallurgical products with a relative standard deviation of not more than 0.04.

  11. Kinetics and Mechanism of Oxidative Dehydrogenation of Propane on Vanadium, Molybdenum, and Tungsten Oxides

    E-Print Network [OSTI]

    Iglesia, Enrique

    Kinetics and Mechanism of Oxidative Dehydrogenation of Propane on Vanadium, Molybdenum catalysts confirmed that oxidative dehydrogenation of propane occurs via similar pathways, which involve for propane dehydrogenation and for propene combustion increase in the sequence VOx/ZrO2

  12. Molecular based magnets comprising vanadium tetracyanoethylene complexes for shielding electromagnetic fields

    DOE Patents [OSTI]

    Epstein, Arthur J. (Columbus, OH); Morin, Brian G. (Columbus, OH)

    1998-01-01T23:59:59.000Z

    The invention presents a vanadium tetracyanoethylene solvent complex for electromagnetic field shielding, and a method for blocking low frequency and magnetic fields using these vanadium tetracyanoethylene compositions. The compositions of the invention can be produced at ambient temperature and are light weight, low density and flexible. The materials of the present invention are useful as magnetic shields to block low frequency fields and static fields, and for use in cores in transformers and motors.

  13. Molecular based magnets comprising vanadium tetracyanoethylene complexes for shielding electromagnetic fields

    DOE Patents [OSTI]

    Epstein, A.J.; Morin, B.G.

    1998-10-13T23:59:59.000Z

    The invention presents a vanadium tetracyanoethylene solvent complex for electromagnetic field shielding, and a method for blocking low frequency and magnetic fields using these vanadium tetracyanoethylene compositions. The compositions of the invention can be produced at ambient temperature and are light weight, low density and flexible. The materials of the present invention are useful as magnetic shields to block low frequency fields and static fields, and for use in cores in transformers and motors. 21 figs.

  14. Redox shuttles for overcharge protection of lithium batteries

    DOE Patents [OSTI]

    Amine, Khalil (Downers Grove, IL); Chen, Zonghai (Downers Grove, IL); Wang, Qingzheng (San Jose, CA)

    2010-12-14T23:59:59.000Z

    The present invention is generally related to electrolytes containing novel redox shuttles for overcharge protection of lithium-ion batteries. The redox shuttles are capable of thousands hours of overcharge tolerance and have a redox potential at about 3-5.5 V vs. Li and particularly about 4.4-4.8 V vs. Li. Accordingly, in one aspect the invention provides electrolytes comprising an alkali metal salt; a polar aprotic solvent; and a redox shuttle additive that is an aromatic compound having at least one aromatic ring with four or more electronegative substituents, two or more oxygen atoms bonded to the aromatic ring, and no hydrogen atoms bonded to the aromatic ring; and wherein the electrolyte solution is substantially non-aqueous. Further there are provided electrochemical devices employing the electrolyte and methods of making the electrolyte.

  15. Tantalum and vanadium response to shock-wave loading at normal and elevated temperatures. Non-monotonous decay of the elastic wave in vanadium

    SciTech Connect (OSTI)

    Zaretsky, E. B. [Department of Mechanical Engineering, Ben Gurion University, 84105 Beer Sheva (Israel); Kanel, G. I. [Joint Institute for High Temperatures RAS, Izhorskaya 13, bld.2, 125412 Moscow (Russian Federation)

    2014-06-28T23:59:59.000Z

    The evolution of the elastic precursor waves in pure tantalum and vanadium is presented at normal and elevated temperatures over propagation distances that ranged from 0.125 to 3?mm. Measurements were performed in order to obtain experimental data about the temperature-rate dependence of the yield stress of the two metals. With increasing propagation distance, the rate of the decay of elastic precursor decreases, as the shear stress in the elastic precursor wave approaches the Peierls stresses. It has been found that the decay, with propagation distance, of the post-spike minimum of the spike-like elastic precursor wave in vanadium is essentially non-monotonous. The experiments also revealed that annealing of tantalum and vanadium increases their Hugoniot elastic limit. The anomalous increase of the high strain rate yield stress with temperature, as observed earlier for some FCC and HCP metals, has not been detected in these measurements.

  16. Preparation of redox polymer cathodes for thin film rechargeable batteries

    DOE Patents [OSTI]

    Skotheim, T.A.; Lee, H.S.; Okamoto, Yoshiyuki.

    1994-11-08T23:59:59.000Z

    The present invention relates to the manufacture of thin film solid state electrochemical devices using composite cathodes comprising a redox polymer capable of undergoing oxidation and reduction, a polymer solid electrolyte and conducting carbon. The polymeric cathode material is formed as a composite of radiation crosslinked polymer electrolytes and radiation crosslinked redox polymers based on polysiloxane backbones with attached organosulfur side groups capable of forming sulfur-sulfur bonds during electrochemical oxidation.

  17. AN UPDATE ON BIAXIAL THERMAL CREEP OF VANADIUM ALLOYS

    SciTech Connect (OSTI)

    Kurtz, Richard J.; Ermi, August M.

    2002-09-01T23:59:59.000Z

    A study of the thermal creep properties of two vanadium alloys was performed using pressurized tube specimens. Creep tubes nominally 4.57 mm OD by 0.25 mm wall thickness were pressurized with high-purity helium gas to mid-wall effective stresses below the effective (Von Mises) yield strength. Specimens were fabricated from V-4Cr-4Ti (Heat No. 832665) and a V-3Fe-4Ti alloy. The samples were heated to 650, 700, 725, and 800 degrees C in an ultra-high vacuum furnace and periodically removed to measure the change in tube outer diameter with a high-precision laser profilometer. The normalized minimum creep rate was found to be power-law dependent on the modulus compensated applied stress. The value of the stress exponent varied with the applied stress. At normalized stresses ranging from 0.002 to 0.008 the stress exponent was about 4 and the activation energy was about 300 kJ/mole, which is quite close to the activation energy for self-diffusion in pure vanadium. These results suggest that the predominant mechanism of creep in this regime is climb-assisted dislocation motion. At lower stresses the value of the stress exponent is near unity suggesting that viscous creep mechanisms such as Coble creep or grain boundary sliding may be operative, but the data are too sparse to be conclusive. The reported creep rates from uniaxial tests [1] in vacuum are several times higher than the creep rates measured here. This is probably due to the larger interstitial oxygen concentration of the creep tubing (699 wppm) compared to the sheet stock (310 wppm) used for tensile specimen fabrication. Finally, the creep strength of V-4Cr-4Ti at 700 and 800 degrees C was superior to the V-3Fe-4Ti alloy.

  18. Fe-phyllosilicate redox cycling organisms from a redox transition zone in Hanford 300 Area sediments

    SciTech Connect (OSTI)

    Benzine, Jason; Shelobolina, Evgenya S.; Xiong, Mai Yia; Kennedy, David W.; McKinley, James P.; Lin, Xueju; Roden, Eric E.

    2013-01-01T23:59:59.000Z

    Microorganisms capable of reducing or oxidizing structural iron (Fe) in Fe-bearing phyllosilicate minerals were enriched and isolated from a subsurface redox transition zone at the Hanford 300 Area site in eastern Washington, USA. Both conventional and in situ "i-chip" enrichment strategies were employed. One Fe(III)-reducing Geobacter (G. bremensis strain R1, Deltaproteobacteria) and six Fe(II) phyllosilicate-oxidizing isolates from the Alphaproteobacteria (Bradyrhizobium japonicum strains 22, is5, and in8p8), Betaproteobacteria (Cupriavidus necator strain A5-1, Dechloromonas agitata strain is5), and Actinobacteria (Nocardioides sp. strain in31) were recovered. The G. bremensis isolate grew by oxidizing acetate with the oxidized form of NAu-2 smectite as the electron acceptor. The Fe(II)-oxidizers grew by oxidation of chemically reduced smectite as the energy source with nitrate as the electron acceptor. The Bradyrhizobium isolates could also carry out aerobic oxidation of biotite. This is the first report of the recovery of a Fe(II)-oxidizing Nocardioides, and to date only one other Fe(II)-oxidizing Bradyrhizobium is known. The 16S rRNA gene sequences of the isolates were similar to ones found in clone libraries from Hanford 300 sediments and groundwater, suggesting that such organisms may be present and active in situ. Whole genome sequencing of the isolates is underway, the results of which will enable comparative genomic analysis of mechanisms of extracellular phyllosilicate Fe redox metabolism, and facilitate development of techniques to detect the presence and expression of genes associated with microbial phyllosilicate Fe redox cycling in sediments.

  19. Chemical bath deposition and characterization of electrochromic thin films of sodium vanadium bronzes

    SciTech Connect (OSTI)

    Najdoski, Metodija, E-mail: metonajd@yahoo.com [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of)] [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of); Koleva, Violeta [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)] [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Demiri, Sani [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of)] [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of)

    2012-03-15T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer We report a new chemical bath method for the deposition of vanadium bronze thin films. Black-Right-Pointing-Pointer The films are phase mixture of NaV{sub 6}O{sub 15} and Na{sub 1.1}V{sub 3}O{sub 7.9} with 10.58% lattice water. Black-Right-Pointing-Pointer The as-deposited vanadium bronze films exhibit two-step electrochromism. Black-Right-Pointing-Pointer They change their yellow-orange color to green and then from green to blue color. Black-Right-Pointing-Pointer The method allows the preparation of films on substrates with low melting point. -- Abstract: Thin yellow-orange films of sodium vanadium oxide bronzes have been prepared from a sodium-vanadium solution (1:1) at 75 Degree-Sign C and pH = 3. The composition, structure and morphology of the films have been studied by XRD, IR spectroscopy, TG and SEM-EDX analyses. It has been established that the prepared films are a phase mixture of hydrated NaV{sub 6}O{sub 15} (predominant component) and Na{sub 1.1}V{sub 3}O{sub 7.9} with total water content of 10.58%. The sodium vanadium bronze thin films exhibit two-step electrochromism followed by color change from yellow-orange to green, and then from green to blue. The cyclic voltammetry measurements on the as-deposited and annealed vanadium bronze films reveal the existence of different oxidation/reduction vanadium sites which make these films suitable for electrochromic devices. The annealing of the films at 400 Degree-Sign C changes the composition, optical and electrochemical properties.

  20. An evaluation of the acute toxicity of vanadium to five estuarine species: Penaeus aztecus, Rangia cuneata, Cyprinodon variegatus, Neanthes arenaceodentata and Brachionus plicatilis / b

    E-Print Network [OSTI]

    Hobson, David Wayne

    1978-01-01T23:59:59.000Z

    the living world, vanadium is found in great quantities only in '. few species wiib no consistency in the freouency of occurrence 'between members of the same genus. Bertrand. (1 943) noted, , for example, that the mushroom Amanita muscaria contained... genus! In the animal kingdom, vanadium also occurs sporadically. Henze (1911) found 42, 000 ppm vanadium in the blood of the ascidian Phsllusi~ mamillata and was first to indicate the presence'of vanadium in an animal, Bertrand (1950) reviewed...

  1. Formation and distribution of neutral vanadium, niobium, and tantalum oxide clusters: Single photon ionization at 26.5 eV

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Formation and distribution of neutral vanadium, niobium, and tantalum oxide clusters: Single photon 2006; accepted 7 September 2006; published online 25 October 2006 Neutral vanadium, niobium neutral clusters of vanadium, niobium, and tantalum oxides are of the general form MO2 0,1 M2O5 y. M2O5

  2. Effects of Dioxin on Clock, Melatonin Biosynthetic, and Redox Sensitive Genes on Chick Pinealocytes In Vitro

    E-Print Network [OSTI]

    Hunt, Jayme

    2006-07-11T23:59:59.000Z

    shown to occur via redox dependent activity of nuclear factor 1 X-type (NF1X) and cellular redox potential can regulate the circadian clock. As such we hypothesized that exposure to dioxin could affect circadian rhythmicity. We explored...

  3. Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina

    E-Print Network [OSTI]

    French, Katherine L. (Katherine Louise)

    2015-01-01T23:59:59.000Z

    Tracing the evolution of Earth's redox history is one of the great challenges of geobiology and geochemistry. The accumulation of photosynthetically derived oxygen transformed the redox state of Earth's surface environments, ...

  4. Metal-ligand redox interaction in the multielectron chemistry of porphyrinogen coordination compounds

    E-Print Network [OSTI]

    Bachmann, Julien

    2006-01-01T23:59:59.000Z

    Metal complexes of the macrocycle porphyrinogen (calix[4]pyrrole) are studied with an emphasis on the redox activity ("non-innocence") of the ligand (Chapter I). Porphyrinogen complexes of spherical, redox-inert metal ...

  5. Solvothermal synthesis of vanadium phosphates in the form of xerogels, aerogels and mesostructures

    SciTech Connect (OSTI)

    Sydorchuk, V.; Zazhigalov, V. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine)] [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Khalameida, S., E-mail: svkhal@ukr.net [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Diyuk, E. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine)] [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine); Skubiszewska-Zieba, J.; Leboda, R. [Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin (Poland)] [Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin (Poland); Kuznetsova, L. [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine)] [Institute of Sorption and Endoecology, National Academy of Sciences of Ukraine, 13 General Naumov Str., Kyiv 03164 (Ukraine)

    2010-09-15T23:59:59.000Z

    Regularities and peculiarities of physicochemical changes, first of all phase transformations, during solvothermal treatment (with conventional and microwave heating) of the vanadium pentoxide and orthophosphoric acid mixture in organic solvents in the presence of reducing agents have been studied. Hemihydrate of vanadium hydrophosphate - the precursor of vanadium pyrophosphate, the active phase for n-butane to maleic anhydride oxidation, and ion exchanger with variable physicochemical characteristics, i.e. crystal structure, specific surface area, crystallite size and acidic properties - has been synthesized in the temperature range 170-200 {sup o}C. The obtained phases were examined using XRD, DTA-TG, SEM, FTIR spectroscopy, nitrogen adsorption as well as gas chromatographic determination of acidity through organic bases adsorption. The catalytic activity of prepared samples for n-butane oxidation has been investigated.

  6. (This is a sample cover image for this issue. The actual cover is not yet available at this time.) This article appeared in a journal published by Elsevier. The attached

    E-Print Network [OSTI]

    Zhao, Tianshou

    does. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Renewable energies like solar and wind in revised form 5 December 2012 Accepted 13 December 2012 Keywords: Flow battery Vanadium redox flow battery with the serpentine flow field at the optimal flow rate shows the high- est energy-based efficiency and round

  7. Structure and properties of a rapidly solidified dispersion strengthened aluminum-iron-vanadium-silicon alloy

    E-Print Network [OSTI]

    Little, Stafford Dean

    1991-01-01T23:59:59.000Z

    Dispersion Strengthened Aluminum-Iron-Vanadium-Silicon Alloy. (December 1991) Stafford Dean Little, B. S. , Texas A&M University Co-Chairs of Advisory Committee: Dr. M. N. Srinivasan Dr. A. Wolfenden A research program has been completed at Texas A...&M University in which the structure and properties of a rapidly solidified dispersion strengthened aluminum-iron- vanadium-silicon alloy were evaluated. A series of melt spun ribbons of FVS1212 (Fe- 11. 5%, V-1. 4%, Si-2. 2%, Al-bal) were produced...

  8. DNA binding shifts the redox potential of the transcription factor SoxR

    E-Print Network [OSTI]

    Dietrich, Lars

    DNA binding shifts the redox potential of the transcription factor SoxR Alon A. Gorodetsky , Lars E-modified electrodes are used to probe the effects of binding to DNA on the redox potential of SoxR, a transcription in the absence of DNA. Using Redmond red as a covalently bound redox reporter affixed above the SoxR binding site

  9. Species-specific residues calibrate SoxR sensitivity to redox-active molecules

    E-Print Network [OSTI]

    Dietrich, Lars

    to viologens, which have redox potentials below -350 mV. Using a mutagenic approach, we pin- pointed threeSpecies-specific residues calibrate SoxR sensitivity to redox-active molecules Rebecca Sheplock,1, the transcription factor SoxR triggers a global stress response by sensing a broad spectrum of redox

  10. Redox Processes and Water Quality of Selected Principal Aquifer Systems

    E-Print Network [OSTI]

    . Similarly, the utilization of solid-phase electron acceptors such as Mn(IV) and Fe(III) is indicated observed at a regional scale. An important finding of this study was that samples indicating mixed redox such as dissolved ferrous iron (Fe21), hydrogen sulfide (H2S), and methane (CH4) (Back and Barnes 1965; Baedecker

  11. Redox Shuttles DOI: 10.1002/anie.201002181

    E-Print Network [OSTI]

    (dicarbollide) Redox Shuttles in Dye-Sensitized Solar Cells** Alexander M. Spokoyny, Tina C. Li, Omar K. Farha, Charles* Dye-sensitized solar cells (DSCs) are potential next-gener- ation solar electricity sources since molecular dyes to increase light absorption,[3] evaluation of alternative semiconducting photoanodes

  12. Adaptive changes in renal mitochondrial redox status in diabetic nephropathy

    SciTech Connect (OSTI)

    Putt, David A.; Zhong, Qing; Lash, Lawrence H., E-mail: l.h.lash@wayne.edu

    2012-01-15T23:59:59.000Z

    Nephropathy is a serious and common complication of diabetes. In the streptozotocin (STZ)-treated rat model of diabetes, nephropathy does not typically develop until 30 to 45 days post-injection, although hyperglycemia occurs within 24 h. We tested the hypothesis that chronic hyperglycemia results in a modest degree of oxidative stress that is accompanied by compensatory changes in certain antioxidants and mitochondrial redox status. We propose that as kidneys progress to a state of diabetic nephropathy, further adaptations occur in mitochondrial redox status. Basic parameters of renal function in vivo and several parameters of mitochondrial function and glutathione (GSH) and redox status in isolated renal cortical mitochondria from STZ-treated and age-matched control rats were examined at 30 days and 90 days post-injection. While there was no effect of diabetes on blood urea nitrogen, measurement of other, more sensitive parameters, such as urinary albumin and protein, and histopathology showed significant and progressive worsening in diabetic rats. Thus, renal function is compromised even prior to the onset of frank nephropathy. Changes in mitochondrial respiration and enzyme activities indicated existence of a hypermetabolic state. Higher mitochondrial GSH content and rates of GSH transport into mitochondria in kidneys from diabetic rats were only partially due to changes in expression of mitochondrial GSH carriers and were mostly due to higher substrate supply. Although there are few clear indicators of oxidative stress, there are several redox changes that occur early and change further as nephropathy progresses, highlighting the complexity of the disease. Highlights: ?Adaptive changes in renal mitochondrial and redox status in diabetic rats. ?Modest renal dysfunction even prior to onset of nephropathy. ?Elevated concentrations of mitochondrial GSH in diabetic kidneys. ?Change in GSH due partly to increased protein expression of transporter. ?Oxidatively modified proteins in renal mitochondria from diabetic rats.

  13. Development and application of a redox indicator method for the kinetics of oxidation of vanadium(II) ions by hydrogen peroxide and alkyl hydroperoxides

    SciTech Connect (OSTI)

    Kim, H.P.; Espenson, J.H.; Bakac, A.

    1987-12-02T23:59:59.000Z

    The addition of the methyl viologen radical cation (PQ/sup .+/) to solutions of V(H/sub 2/O)/sub 6//sup 2 +/ and hydrogen peroxide or alkyl hydroperoxide provides a method for measuring the initial reaction rate. The kinetic data so obtained are consistent with the rate equation -d(peroxide)/dt = k/sub 1/(V/sup 2 +/)(peroxide). Kinetic data are given for H/sub 2/O/sub 2/ (k/sub 1/ = 15.4 M/sup -1/ s/sup -1/ at 25.0/sup 0/C) and for RC(CH/sub 3/)/sub 2/OOH, with R = CH/sub 3/ (3.0 M/sup -1/ s/sup -1/), C/sub 2/H/sub 5/ (5.2 M/sup -1/ s/sup -1/), and CH/sub 2/C/sub 6/H/sub 5/ (4.8 M/sup -1/ s/sup -1/). 27 references, 2 figures, 2 tables.

  14. Removal of arsenic, vanadium and/or nickel compounds from spent catecholated polymer

    DOE Patents [OSTI]

    Fish, R.H.

    1987-04-21T23:59:59.000Z

    Described is a process for removing arsenic, vanadium, and/or nickel from petroliferous derived liquids by contacting said liquid at an elevated temperature with a divinylbenzene-crosslinked polystyrene having catechol ligands anchored thereon. For vanadium and nickel removal an amine, preferably a diamine is included. Also, described is a process for regenerating spent catecholated polystyrene by removal of the arsenic, vanadium, and/or nickel bound to it from contacting petroliferous liquid as described above and involves: treating the spent polymer containing any vanadium and/or nickel with an aqueous acid to achieve an acid pH; and, separating the solids from the liquid; and then treating said spent catecholated polystyrene, at a temperature in the range of about 20 to 100 C with an aqueous solution of at least one carbonate and/or bicarbonate of ammonium, alkali and alkaline earth metals, said solution having a pH between about 8 and 10; and, separating the solids and liquids from each other. Preferably the regeneration treatment of arsenic containing catecholated polymer is in two steps wherein the first step is carried out with an aqueous alcoholic carbonate solution containing lower alkyl alcohol, and, the steps are repeated using a bicarbonate.

  15. Hydrogen-impurity binding energy in vanadium and niobium A. Mokrani and C. Demangeat

    E-Print Network [OSTI]

    Boyer, Edmond

    2243 Hydrogen-impurity binding energy in vanadium and niobium A. Mokrani and C. Demangeat IPCMS, UM by the hydrogen) contribution, ii) the band structure contribution, iii) the electron-electron interaction without. Strong H-H repulsion is observed when the hydrogen atoms are at first nearest neighbouring positions

  16. Thermodynamic considerations for the use of vanadium alloys with ceramic breeder materials

    SciTech Connect (OSTI)

    Johnson, C.E.; Johnson, I.; Kopasz, J.P.

    1995-12-31T23:59:59.000Z

    Fusion energy is considered to be an attractive energy form because of its minimal environmental impact. In order to maintain this favorable status, every effort needs to be made to use low activation materials wherever possible. The tritium breeder blanket is a focal point of system design engineers who must design environmentally attractive blankets through the use of low activation materials. Of the several candidate lithium-containing ceramics being considered for use in the breeder blanket, Li{sub 2}O, Li{sub 2}TiO{sub 3}, are attractive choices because of their low activation. Also, low activation materials like the vanadium alloys are being considered for use as structural materials in the blanket. The suitability of vanadium alloys for containment of lithium ceramics is the subject of this study. Thermodynamic evaluations are being used to estimate the compatibility and stability of candidate ceramic breeder materials (Li{sub 2}O, Li{sub 2}TiO{sub 3}, and Li{sub 2}ZrO{sub 3}) with vanadium and vanadium alloys. This thermodynamic evaluation will focus first on solid-solid interactions. As a tritium breeding blanket will use a purge gas for tritium recovery, gas-solid systems will also receive attention.

  17. Study of lithium diffusion in RF sputtered Nickel/Vanadium mixed oxides thin films

    E-Print Network [OSTI]

    Artuso, Florinda

    Study of lithium diffusion in RF sputtered NickelÁ/Vanadium mixed oxides thin films F. Artuso a lithium insertion inside RF sputtered Ni/V mixed oxides thin films have been investigated employing, showed three steps clearly involved in the intercalation mechanism of lithium in the oxide films: (i

  18. Abundances of Vanadium and Bromine in 3 Cen A: Additional Odd-Z Anomalies

    E-Print Network [OSTI]

    C. R. Cowley; G. M. Wahlgren

    2005-12-12T23:59:59.000Z

    We report abundance excesses of 1.2 and 2.6 dex, respectively, for vanadium and bromine in the hot, peculiar star 3 Cen A. Abundances for these two odd-Z elements have not been previously reported for this star. Taken with previous work, they strengthen the case of the origin of the abundance peculiarities by diffusion.

  19. Removal of arsenic, vanadium, and/or nickel compounds from petroliferous liquids

    DOE Patents [OSTI]

    Fish, R.H.

    1985-05-17T23:59:59.000Z

    Described is a process for removing arsenic, vanadium, and/or nickel from petroliferous derived liquids (shale oil, SRC, etc.) by contacting said liquid at an elevated temperature with a divinylbenzene-crosslinked polystyrene having catechol ligands anchored thereon. For vanadium and nickel removal an amine, preferably a diamine is included. Also, described is a process for regenerating spent catecholated polystyrene by removal of the arsenic, vanadium, and/or nickel bound to it from contacting petroliferous liquid as described above and involves: treating the spent polymer containing any vanadium and/or nickel with an aqueous acid to achieve an acid pH; and, separating the solids from the liquid; and then treating said spent catecholated polystyrene, at a temperature in the range of about 20/sup 0/ to 100/sup 0/C with an aqueous solution of at least one carbonate and/or bicarbonate of ammonium, alkali and alkaline earth metals, said solution having a pH between about 8 and 10; and, separating the solids and liquids from each other. Preferably the regeneration treatment of arsenic containing catecholated polymer is in two steps wherein the first step is carried out with an aqueous alcoholic carbonate solution containing lower alkyl alcohol, and, the steps are repeated using a bicarbonate.

  20. Production and fabrication of vanadium alloys for the radiative divertor program of DIII-D

    SciTech Connect (OSTI)

    Johnson, W.R.; Smith, J.P.; Stambaugh, R.D.

    1996-04-01T23:59:59.000Z

    V-4Cr-4-Ti alloy has been recently selected for use in the manufacture of a portion of the DIII-D Radiative Divertor modification, as part of an overall DIII-D vanadium alloy deployment effort developed by General Atomics (GA) in conjunction with the Argonne and Oak Ridge National Laboratories (ANL or ORNL). The goal of this work is to produce a production-scale heat of the alloy and fabricate it into product forms for the manufacture of a portion of the Radiative Divertor (RD) for the DIII-D tokamak, to develop the fabrications technology for manufacture of the vanadium alloy radiative Divertor components, and to determine the effects of typical tokamak environments in the behavior of the vanadium alloy. The production of a {approx}1300-kg heat of V-4Cr-4Ti alloy is currently in progress at Teledyne Wah Chang of Albany, oregon (TWCA) to provide sufficient material for applicable product forms. Two unalloyed vanadium ingots for the alloy have already been produced by electron beam melting of raw processes vanadium. Chemical compositions of one ingot and a portion of the second were acceptable, and Charpy V-Notch (CVN) impact test performed on processed ingot samples indicated ductile behavior. Material from these ingots are currently being blended with chromium and titanium additions, and will be vacuum-arc remelted into a V-4Cr-4Ti alloy ingot and converted into product forms suitable for components of the DIII-D RD structure. Several joining methods selected for specific applications in fabrication of the RD components are being investigated, and preliminary trials have been successful in the joining of V-alloy to itself by both resistance and inertial welding processes and to Inconel 625 by inertial welding.

  1. Live Cell Chemical Profiling of Temporal Redox Dynamics in a Photoautotrophic Cyanobacterium

    SciTech Connect (OSTI)

    Sadler, Natalie C.; Melnicki, Matthew R.; Serres, Margrethe H.; Merkley, Eric D.; Chrisler, William B.; Hill, Eric A.; Romine, Margaret F.; Kim, Sangtae; Zink, Erika M.; Datta, Suchitra; Smith, Richard D.; Beliaev, Alex S.; Konopka, Allan; Wright, Aaron T.

    2014-01-01T23:59:59.000Z

    Protein reduction-oxidation (redox) modification is an important mechanism that allows microorganisms to sense environmental changes and initiate cellular responses. We have developed a quantitative chemical probe approach for live cell labeling of proteins that are sensitive to redox modifications. We utilize this in vivo strategy to identify 176 proteins undergoing ~5-10 fold dynamic redox change in response to nutrient limitation and subsequent replenishment in the photoautotrophic cyanobacterium, Synechococcus sp. PCC 7002. We detect redox changes in as little as 30 seconds after nutrient perturbation, and oscillations in reduction and oxidation for 60 minutes following the perturbation. Many of the proteins undergoing dynamic redox transformations participate in the major components for the production (photosystems and electron transport chains) or consumption (Calvin-Benson cycle and protein synthesis) of reductant and/or energy in photosynthetic organisms. Thus, our in vivo approach reveals new redox-susceptible proteins, in addition to validating those previously identified in vitro.

  2. Lithium borate cluster salts as novel redox shuttles for overcharge protection of lithium-ion cells.

    SciTech Connect (OSTI)

    Chen, Z.; Liu, J.; Jansen, A. N.; Casteel, B.; Amine, K.; GirishKumar, G.; Air Products and Chemicals, Inc.

    2010-01-01T23:59:59.000Z

    Redox shuttle is a promising mechanism for intrinsic overcharge protection in lithium-ion cells and batteries. Two lithium borate cluster salts are reported to function as both the main salt for a nonaqueous electrolyte and the redox shuttle for overcharge protection. Lithium borate cluster salts with a tunable redox potential are promising candidates for overcharge protection for most positive electrodes in state-of-the-art lithium-ion cells.

  3. Redox Characterization of Proteins Involved in the Mitochondrial Intermembrane Space Pathway

    E-Print Network [OSTI]

    Neal, Sonya Elina

    2013-01-01T23:59:59.000Z

    Bardwell. 1999. Oxidative protein folding is driven by theRedox regulation of protein folding in the mitochondrial2008. Disulfide-linked protein folding pathways. Annu. Rev.

  4. Tungsten Coating on Low Activation Vanadium Alloy by Plasma Spray Process

    SciTech Connect (OSTI)

    Nagasaka, Takuya [National Institute for Fusion Science (Japan); Muroga, Takeo [National Institute for Fusion Science (Japan); Noda, Nobuaki [National Institute for Fusion Science (Japan); Kawamura, Masashi [Kawasaki Heavy Industries, LTD (Japan); Ise, Hideo [Kawasaki Heavy Industries, LTD (Japan); Kurishita, Hiroaki [Tohoku University (Japan)

    2005-05-15T23:59:59.000Z

    Tungsten (W) coating on fusion candidate V-4Cr-4Ti (NIFS-HEAT-2) substrate was demonstrated with plasma spray process for the purpose of applying to protection of the plasma facing surface of a fusion blanket. Increase in plasma input power and temperature of the substrate was effective to reduce porosity of the coating, but resulted in hardening of the substrate and degradation of impact property at 77 K. The hardening seemed to be due to contamination with gaseous impurities and deformation by thermal stress during the coating process. Since all the samples showed good ductility at room temperature, further heating seems to be acceptable for the vanadium substrate. The fracture stress of the W coating was estimated from bending tests as at least 313 MPa, which well exceeds the design stress for the vanadium structure in fusion blanket.

  5. Multiplier, moderator, and reflector materials for lithium-vanadium fusion blankets.

    SciTech Connect (OSTI)

    Gohar, Y.; Smith, D. L.

    1999-10-07T23:59:59.000Z

    The self-cooled lithium-vanadium fusion blanket concept has several attractive operational and environmental features. In this concept, liquid lithium works as the tritium breeder and coolant to alleviate issues of coolant breeder compatibility and reactivity. Vanadium alloy (V-4Cr-4Ti) is used as the structural material because of its superior performance relative to other alloys for this application. However, this concept has poor attenuation characteristics and energy multiplication for the DT neutrons. An advanced self-cooled lithium-vanadium fusion blanket concept has been developed to eliminate these drawbacks while maintaining all the attractive features of the conventional concept. An electrical insulator coating for the coolant channels, spectral shifter (multiplier, and moderator) and reflector were utilized in the blanket design to enhance the blanket performance. In addition, the blanket was designed to have the capability to operate at high loading conditions of 2 MW/m{sup 2} surface heat flux and 10 MW/m{sup 2} neutron wall loading. This paper assesses the spectral shifter and the reflector materials and it defines the technological requirements of this advanced blanket concept.

  6. The geochemistry of redox sensitive trace metals in sediments

    SciTech Connect (OSTI)

    Morford, J.L.; Emerson, S. [Univ. of Washington, Seattle, WA (United States). School of Oceanography] [Univ. of Washington, Seattle, WA (United States). School of Oceanography

    1999-06-01T23:59:59.000Z

    The authors analyzed the redox sensitive elements V, Mo, U, Re and Cd in surface sediments from the Northwest African margin, the US Northwest margin and the Arabian Sea to determine their response under a range of redox conditions. Where oxygen penetrates 1 cm or less into the sediments, Mo and V diffuse to the overlying water as Mn is reduced and remobilized. Authigenic enrichments of U, Re and Cd are evident under these redox conditions. With the onset of sulfate reduction, all of the metals accumulate authigenically with Re being by far the most enriched. General trends in authigenic metal accumulation are described by calculating authigenic fluxes for the 3 main redox regimes: oxic, reducing where oxygen penetrates {le} 1 cm, and anoxic conditions. Using a simple diagenesis model and global estimates of organic carbon rain rate and bottom water oxygen concentrations, the authors calculate the area of sediments below 1,000 m water depth in which oxygen penetration is {le} 1 cm to be 4% of the ocean floor. They conclude that sediments where oxygen penetrates {le} 1 cm release Mn, V and Mo to seawater at rates of 140%--260%, 60%--150% and 5%--10% of their respective riverine fluxes, using the authigenic metal concentrations and accumulation rates from this work and other literature. These sediments are sinks for Re, Cd and U, with burial fluxes of 70%--140%, 30%--80% and 20%--40%, respectively, of their dissolved riverine inputs. They modeled the sensitivity of the response of seawater Re, Cd and V concentrations to changes in the area of reducing sediments where oxygen penetrates {le} 1 cm. The analysis suggests a negligible change in seawater Re concentration, whereas seawater concentrations of Cd and V could have decreased and increased, respectively, by 5%--10% over 20 kyr if the area of reducing sediments increased by a factor of 2 and by 10%--20% if the area increased by a factor of 3. The concentration variations for a factor of 2 increase in the area of reducing sediments are at about the level of uncertainty of Cd/Ca and V/Ca ratios observed in foraminifera shells over the last 40 kyr. This implies that the area of reducing sediments in the ocean deeper than 1,000 m (4%) has not been greater than twice the present value in the recent past.

  7. Controlled Chemical Doping of Semiconductor Nanocrystals Using Redox Buffers

    SciTech Connect (OSTI)

    Engel, Jesse H.; Surendranath, Yogesh; Alivisatos, Paul

    2013-07-09T23:59:59.000Z

    Semiconductor nanocrystal solids are attractive materials for active layers in next-generation optoelectronic devices; however, their efficient implementation has been impeded by the lack of precise control over dopant concentrations. Herein we demonstrate a chemical strategy for the controlled doping of nanocrystal solids under equilibrium conditions. Exposing lead selenide nanocrystal thin films to solutions containing varying proportions of decamethylferrocene and decamethylferrocenium incrementally and reversibly increased the carrier concentration in the solid by 2 orders of magnitude from their native values. This application of redox buffers for controlled doping provides a new method for the precise control of the majority carrier concentration in porous semiconductor thin films.

  8. Photocurrent generation by photosystem 1 integrated in crosslinked redox Adrian Badura,a

    E-Print Network [OSTI]

    Roegner, Matthias

    Photocurrent generation by photosystem 1 integrated in crosslinked redox hydrogels Adrian Badura on a gold electrode surface via an Os complex containing redox polymer hydrogel which simultaneously is used as immobilisation matrix and as electron donor for PS1. On addition of methyl viologen as sacrificial electron

  9. Ab initio electronic structure calculation of the redox potentials of bacteriochlorophyll and bacteriopheophytin in solution

    SciTech Connect (OSTI)

    Zhang, L.Y.; Friesner, R.A. [Columbia Univ., New York, NY (United States)

    1995-11-02T23:59:59.000Z

    We have carried out self-consistent reaction field (SCRF) calculations on the bacteriochlorophyll (BChl) and bacteriopheophytin (BPh) molecules at the Hartree-Fock level using the ab initio electronic structure code PSGVB together with an accurate numerical Poisson-Boltzmann solver. These are by far the largest ab initio SCRF computations carried out to date. We calculate redox potentials of these molecules in DMF solution for several geometries and compare the results with experiments of Fajer and co-workers. While the absolute redox energies are substantially in error, due to neglect of electron correlation, the relative redox energies agree qualitatively with the experimental findings. Treatment of solvation is crucial in predicting the proper ordering of the BChl and BPh redox energies. These results have implications for calculation of redox energies of the chromophores in the photosynthetic reaction center. 23 refs., 2 figs., 2 tabs.

  10. A catalytic approach to estimate the redox potential of heme-peroxidases

    SciTech Connect (OSTI)

    Ayala, Marcela [Departamento de Ingenieria Celular y Biocatalisis, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Cuernavaca, Morelos 62210 (Mexico)]. E-mail: maa@ibt.unam.mx; Roman, Rosa [Departamento de Ingenieria Celular y Biocatalisis, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Cuernavaca, Morelos 62210 (Mexico); Vazquez-Duhalt, Rafael [Departamento de Ingenieria Celular y Biocatalisis, Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Cuernavaca, Morelos 62210 (Mexico)

    2007-06-08T23:59:59.000Z

    The redox potential of heme-peroxidases varies according to a combination of structural components within the active site and its vicinities. For each peroxidase, this redox potential imposes a thermodynamic threshold to the range of oxidizable substrates. However, the instability of enzymatic intermediates during the catalytic cycle precludes the use of direct voltammetry to measure the redox potential of most peroxidases. Here we describe a novel approach to estimate the redox potential of peroxidases, which directly depends on the catalytic performance of the activated enzyme. Selected p-substituted phenols are used as substrates for the estimations. The results obtained with this catalytic approach correlate well with the oxidative capacity predicted by the redox potential of the Fe(III)/Fe(II) couple.

  11. Nature Macmillan Publishers Ltd 1997 of composition, temperature, oxygen fugacity and pressure on their redox states. Contrib. Mineral.

    E-Print Network [OSTI]

    Dominey, Peter F.

    on their redox states. Contrib. Mineral. Petrol. 108, 82­92 (1991). 22. Eggler, D. H. & Lorand, J. P. Sulfides

  12. Methane oxidation over dual redox catalysts. Final report

    SciTech Connect (OSTI)

    Klier, K.; Herman, R.G.; Sojka, Z.; DiCosimo, J.I.; DeTavernier, S.

    1992-06-01T23:59:59.000Z

    Catalytic oxidation of methane to partial oxidation products, primarily formaldehyde and C{sub 2} hydrocarbons, was found to be directed by the catalyst used. In this project, it was discovered that a moderate oxidative coupling catalyst for C{sub 2} hydrocarbons, zinc oxide, is modified by addition of small amounts of Cu and Fe dopants to yield fair yields of formaldehyde. A similar effect was observed with Cu/Sn/ZnO catalysts, and the presence of a redox Lewis acid, Fe{sup III} or Sn{sup IV}, was found to be essential for the selectivity switch from C{sub 2} coupling products to formaldehyde. The principle of double doping with an oxygen activator (Cu) and the redox Lewis acid (Fe, Sn) was pursued further by synthesizing and testing the CuFe-ZSM-5 zeolite catalyst. The Cu{sup II}(ion exchanged) Fe{sup III}(framework)-ZSM-5 also displayed activity for formaldehyde synthesis, with space time yields exceeding 100 g/h-kg catalyst. However, the selectivity was low and earlier claims in the literature of selective oxidation of methane to methanol over CuFe-ZSM-5 were not reproduced. A new active and selective catalytic system (M=Sb,Bi,Sn)/SrO/La{sub 2}O{sub 3} has been discovered for potentially commercially attractive process for the conversion of methane to C{sub 2} hydrocarbons, (ii) a new principle has been demonstrated for selectivity switching from C{sub 2} hydrocarbon products to formaldehyde in methane oxidations over Cu,Fe-doped zinc oxide and ZSM-5, and (iii) a new approach has been initiated for using ultrafine metal dispersions for low temperature activation of methane for selective conversions. Item (iii) continues being supported by AMOCO while further developments related to items (i) and (ii) are the objective of our continued effort under the METC-AMOCO proposed joint program.

  13. Sorption of redox-sensitive elements: critical analysis

    SciTech Connect (OSTI)

    Strickert, R.G.

    1980-12-01T23:59:59.000Z

    The redox-sensitive elements (Tc, U, Np, Pu) discussed in this report are of interest to nuclear waste management due to their long-lived isotopes which have a potential radiotoxic effect on man. In their lower oxidation states these elements have been shown to be highly adsorbed by geologic materials occurring under reducing conditions. Experimental research conducted in recent years, especially through the Waste Isolation Safety Assessment Program (WISAP) and Waste/Rock Interaction Technology (WRIT) program, has provided extensive information on the mechanisms of retardation. In general, ion-exchange probably plays a minor role in the sorption behavior of cations of the above three actinide elements. Formation of anionic complexes of the oxidized states with common ligands (OH/sup -/, CO/sup - -//sub 3/) is expected to reduce adsorption by ion exchange further. Pertechnetate also exhibits little ion-exchange sorption by geologic media. In the reduced (IV) state, all of the elements are highly charged and it appears that they form a very insoluble compound (oxide, hydroxide, etc.) or undergo coprecipitation or are incorporated into minerals. The exact nature of the insoluble compounds and the effect of temperature, pH, pe, other chemical species, and other parameters are currently being investigated. Oxidation states other than Tc (IV,VII), U(IV,VI), Np(IV,V), and Pu(IV,V) are probably not important for the geologic repository environment expected, but should be considered especially when extreme conditions exist (radiation, temperature, etc.). Various experimental techniques such as oxidation-state analysis of tracer-level isotopes, redox potential measurement and control, pH measurement, and solid phase identification have been used to categorize the behavior of the various valence states.

  14. Redox control of electric melters with complex feed compositions. Part I: analytical methods and models

    SciTech Connect (OSTI)

    Bickford, D F; Diemer, Jr, R B

    1985-01-01T23:59:59.000Z

    The redox state of glass from electric melters with complex feed compositions is determined by balance between gases above the melt, and transition metals and organic compounds in the feed. Part I discusses experimental and computational methods of relating flowrates and other melter operating conditions to the redox state of glass, and composition of the melter offgas. Computerized thermodynamic computational methods are useful in predicting the sequence and products of redox reactions and in assessing individual process variations. Melter redox state can be predicted by combining monitoring of melter operating conditions, redox measurement of fused melter feed samples, and periodic redox measurement of product. Mossbauer spectroscopy, and other methods which measure Fe(II)/Fe(III) in glass, can be used to measure melter redox state. Part II develops preliminary operating limits for the vitrification of High-Level Radioactive Waste. Limits on reducing potential to preclude the accumulation of combustible gases, accumulation of sulfides and selenides, and degradation of melter components are the most critical. Problems associated with excessively oxidizing conditions, such as glass foaming and potential ruthenium volatility, are controlled when sufficient formic acid is added to adjust melter feed rheology.

  15. Continuum Level Formulation and Implementation of a Multi-scale Model for Vanadium

    SciTech Connect (OSTI)

    Lawrence Livermore National Laboratory

    2009-08-17T23:59:59.000Z

    A multi-scale approach is used to construct a continuum strength model for vanadium. The model is formulated assuming plastic deformation by dislocation motion and strain hardening due to dislocation interactions. Dislocation density is adopted as the state variable in the model. Information from molecular statics, molecular dynamics and dislocation dynamics simulations is combined to create kinetic relations for dislocation motion, strain hardening relations and evolution equations for the dislocation density. Implicit time integration of the constitutive equations is described in the context of implementation in a finite element code. Results are provided illustrating the strain, strain rate, temperature and pressure dependence of the constitutive model.

  16. Chemical structure of vanadium-based contact formation on n-AlN

    SciTech Connect (OSTI)

    Pookpanratana, S.; France, R.; Blum, M.; Bell, A.; Bar, M.; Weinhardt, L.; Zhang, Y.; Hofmann, T.; Fuchs, O.; Yang, W.; Denlinger, J. D.; Mulcahy, S.; Moustakas, T. D.; Heske, Clemens

    2010-05-17T23:59:59.000Z

    We have investigated the chemical interaction between a Au/V/Al/V layer structure and n-type AlN epilayers using soft x-ray photoemission, x-ray emission spectroscopy, and atomic force microscopy. To understand the complex processes involved in this multicomponent system, we have studied the interface before and after a rapid thermal annealing step. We find the formation of a number of chemical phases at the interface, including VN, metallic vanadium, aluminum oxide, and metallic gold. An interaction mechanism for metal contact formation on the entire n-(Al,Ga)N system is proposed.

  17. DOE - Office of Legacy Management -- Vanadium Corp of America - PA 15

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilA group currentBradleyTableSelling Corp -K LeDowntownUnitedCenter -Vanadium Corp of

  18. An Improved Equilibrium-Kinetics Speciation Algorithm For Redox...

    Open Energy Info (EERE)

    The REACT speciation model was coupled with the multidimensional nonisothermal multiphase flow and mass transport code TOUGH2, resulting in the general purpose reactive...

  19. Some lessons learned from 20 years in RedOx Flow Battery R&D

    E-Print Network [OSTI]

    balancing pressure (low p) Materials Novel nano-structured non- carbon electrodes Novel low cost option Now ubiquitous on all large wind farms Utilities understand them ­ and feed them Extensively must power itself and this imposes complex trade offs, e.g: High voltage couples and reactive

  20. Membranes Optimized for High Conductivity and Low Crossover of Redox Flow

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The EnergyCenter (LMI-EFRC)MaRIETechnologies |meetingsat

  1. Transitioning from Fuel Cells to Redox Flow Cells | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic|IndustrialCenter Gets People Work,Amy7AUnderstanding |

  2. Redox Flow Batteries for Grid-scale Energy Storage - Energy Innovation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection RadiationRecord-SettingHead of Contracting Activity

  3. Direct Observation of Nanoscale Peltier and Joule Effects at Metal-Insulator Domain Walls in Vanadium Dioxide Nanobeams

    E-Print Network [OSTI]

    Wu, Junqiao

    Direct Observation of Nanoscale Peltier and Joule Effects at Metal- Insulator Domain Walls localized alternating Peltier heating and cooling as well as Joule heating concentrated at the M-I domain the monoclinic phase identification. KEYWORDS: Vanadium dioxide, thermoreflectance microscopy, Peltier effect

  4. Mechanism and Site Requirements for Ethanol Oxidation on Vanadium Oxide Domains Beata Kilos, Alexis T. Bell,* and Enrique Iglesia*

    E-Print Network [OSTI]

    Bell, Alexis T.

    Mechanism and Site Requirements for Ethanol Oxidation on Vanadium Oxide Domains Beata Kilos, Alexis for ethanol oxidation to acetaldehyde were examined on VOx domains supported on -Al2O3 at surface densities dehydrogenation (ODH) of ethanol to acetaldehyde occurs at low temperatures (473-523 K) with high primary

  5. Consequences of redox-active phenazines on the physiology of the opportunistic pathogen Pseudomonas aeruginosa

    E-Print Network [OSTI]

    Kern, Suzanne E

    2013-01-01T23:59:59.000Z

    Phenazines are redox-active small molecules produced by bacteria. Although phenazines have been studied extensively for their roles as toxins, how phenazines benefit producing organisms is still being uncovered. Pseudomonas ...

  6. The role of Ncb5or in fatty acid metabolism and redox homeostasis

    E-Print Network [OSTI]

    Xu, Ming

    2011-12-31T23:59:59.000Z

    The endoplasmic reticulum (ER)-associated NADH cytochrome b5 oxidoreductase (Ncb5or) is widely distributed in animal tissues. It contains two redox domains that are homologous to microsomal cytochrome b5 (Cyb5A) at the N ...

  7. Molecular cloning and characterization of important stress and redox regulatory genes from Hydra vulgaris

    E-Print Network [OSTI]

    Dash, Bhagirathi

    2007-04-25T23:59:59.000Z

    In this research, important stress and redox regulatory genes present in Hydra vulgaris were isolated and characterized to facilitate our understanding of the evolution and mechanisms of stress response. H. vulgaris heat shock protein 70 (HvHSP70...

  8. Nickel Phase Wettability and YSZ Redox Fracture Percolation in Solid Oxide Fuel Cell Anodes

    E-Print Network [OSTI]

    Petta, Jason

    Nickel Phase Wettability and YSZ Redox Fracture Percolation in Solid Oxide Fuel Cell Anodes Alex and Aerospace Engineering Background Solid oxide fuel cells lose mechanical stability and functionality when

  9. Hybrid density functional calculations of redox potentials and formation energies of transition metal compounds

    E-Print Network [OSTI]

    Ceder, Gerbrand

    We compare the accuracy of conventional semilocal density functional theory (DFT), the DFT+U method, and the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional for structural parameters, redox reaction energies, and formation ...

  10. Transimination of Quinone Imines: A Mechanism for Embedding Exogenous Redox Activity into the Nucleosome

    E-Print Network [OSTI]

    Ye, Wenjie

    Aminophenols can redox cycle through the corresponding quinone imines to generate ROS. The electrophilic quinone imine intermediate can react with protein thiols as a mechanism of immobilization in vivo. Here, we describe ...

  11. Anaerobic Redox Cycling of Iron by Freshwater Sediment Microorganisms

    SciTech Connect (OSTI)

    Weber, Karrie A.; Urrutia, Matilde M.; Churchill, Perry F.; Kukkadapu, Ravi K.; Roden, Eric E.

    2006-01-01T23:59:59.000Z

    The potential for microbially-mediated anaerobic redox cycling of iron (Fe) was examined in a first-generation enrichment culture of freshwater wetland sediment microorganisms. MPN enumerations revealed the presence of significant populations of Fe(III)-reducing (ca. 108 cells mL-1) and Fe(II)-oxidizing, nitrate-reducing organisms (ca. 105 cells mL-1) in the sediment used to inoculate the enrichment cultures. Nitrate reduction commenced immediately following inoculation of acetate-containing (ca. 1 mM) medium with a small quantity (1% vol/vol) of wetland sediment, and resulted in the transient accumulation of NO2- and production of a mixture of end-products including NH4+. Fe(III) oxide (high surface area goethite) reduction took place - after NO3- was depleted and continued until all the acetate was utilized. Addition of NO3 after Fe(III) reduction ceased resulted in the immediate oxidation of Fe(II) coupled to reduction of + NO3-to NH4 . No significant NO2- accumulation was observed during nitrate-dependent Fe(II) oxidation. No Fe(II) oxidation occurred in pasteurized controls. Microbial community structure in the enrichment was monitored by DGGE analysis of PCR amplified 16s rDNA and RT-PCR amplified 16S rRNA, as well as by construction of 16S rDNA clone libraries for four different time points during the experiment. Strong similarities in dominant members of the microbial community were observed in the Fe(III) reduction and nitrate-dependent Fe(II) oxidation phases of the experiment, specifically the common presence of organisms closely related (= 95% sequence similarity) to the genera Geobacter and Dechloromonas. These results indicate that the wetland sediments contained organisms such as Geobacter sp. which are capable of both + dissimilatory Fe(III) reduction and oxidation of Fe(II) with reduction of NO3-reduction to NH4 . Our findings suggest that microbially-catalyzed nitrate-dependent Fe(II) oxidation has the potential to contribute to a dynamic anaerobic Fe redox cycle in freshwater sediments.

  12. Redox reaction and foaming in nuclear waste glass melting

    SciTech Connect (OSTI)

    Ryan, J.L.

    1995-08-01T23:59:59.000Z

    This document was prepared by Pacific Northwest Laboratory (PNL) and is an attempt to analyze and estimate the effects of feed composition variables and reducing agent variables on the expected chemistry of reactions occurring in the cold cap and in the glass melt in the nuclear waste glass Slurry-fed, joule-heated melters as they might affect foaming during the glass-making process. Numerous redox reactions of waste glass components and potential feed additives, and the effects of other feed variables on these reactions are reviewed with regard to their potential effect on glass foaming. A major emphasis of this report is to examine the potential positive or negative aspects of adjusting feed with formic acid as opposed to other feed modification techniques including but not limited to use of other reducing agents. Feed modification techniques other than the use of reductants that should influence foaming behavior include control of glass melter feed pH through use of nitric acid. They also include partial replacement of sodium salts by lithium salts. This latter action (b) apparently lowers glass viscosity and raises surface tension. This replacement should decrease foaming by decreasing foam stability.

  13. Energy Storage for the Power Grid

    SciTech Connect (OSTI)

    Imhoff, Carl; Vaishnav, Dave

    2014-07-01T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid. This technology provides the energy industry and the nation with a reliable, stable, safe, and low-cost storage alternative for a cleaner, efficient energy future.

  14. 100-D Area In Situ Redox Treatability Test for Chromate-Contaminated Groundwater

    SciTech Connect (OSTI)

    Williams, Mark D.; Vermeul, Vincent R.; Szecsody, James E.; Fruchter, Jonathan S.

    2000-10-12T23:59:59.000Z

    A treatability test was conducted for the In Situ Redox Manipulation (ISRM) technology at the 100 D Area of the U. S. Department of Energy's Hanford Site. The target contaminant was dissolved chromate in groundwater. The ISRM technology creates a permeable subsurface treatment zone to reduce mobile chromate in groundwater to an insoluble form. The ISRM permeable treatment zone is created by reducing ferric iron to ferrous iron within the aquifer sediments, which is accomplished by injecting aqueous sodium dithionite into the aquifer and then withdrawing the reaction products. The goal of the treatability test was to create a linear ISRM barrier by injecting sodium dithionite into five wells. Well installation and site characterization activities began in spring 1997; the first dithionite injection took place in September 1997. The results of this first injection were monitored through the spring of 1998. The remaining four dithionite injections were carried out in May through July of 1998.These five injections created a reduced zone in the Hanford unconfined aquifer approximately 150 feet in length (perpendicular to groundwater flow) and 50 feet wide. The reduced zone extended over the thickness of the unconfined zone. Analysis of post-emplacement groundwater samples showed concentrations of chromate, in the reduced zone decreased from approximately 1.0 mg/L before the tests to below analytical detection limits (<0.007 mg/L). Chromate concentrations also declined in downgradient monitoring wells to as low as 0.020 mg/L. These data, in addition to results from pre-test reducible iron characterization, indicate the barrier should be effective for 20 to 25 years. The 100-D Area ISRM barrier is being expanded to a length of up to 2,300 ft to capture a larger portion of the chromate plume.

  15. Intermolecular CH bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Intermolecular C­H bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to a vanadium-benzyne complex Jose G. Andino,a Uriah J. Kilgore,a Maren Pink of benzene and pyridine is observed with (PNP)V(CH2tBu)2 (1), and in the case of benzene, the formation

  16. A New Direction in Dye-Sensitized Solar Cells Redox Mediator Development: In Situ Fine-Tuning of the Cobalt(II)/(III) Redox

    E-Print Network [OSTI]

    A New Direction in Dye-Sensitized Solar Cells Redox Mediator Development: In Situ Fine 3168, Australia *S Supporting Information ABSTRACT: Dye-sensitized solar cells (DSCs) are an attractive to tackle present and future energy challenges. Dye-sensitized solar cells (DSCs) are considered

  17. Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper

    SciTech Connect (OSTI)

    Akyurtlu, A.; Akyurtlu, J.F.

    1992-01-01T23:59:59.000Z

    The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

  18. Transport properties of lithium- lead-vanadium-telluride glass and glass ceramics

    SciTech Connect (OSTI)

    Sathish, M., E-mail: sathishphy79@gmail.com [Department of Physics, GOVT first grade College, Doddaballapur-561203 (India); Eraiah, B., E-mail: eraiah@rediffmail.com [Department of Physics, Bangalore University, Bangalore-560056, India (India)

    2014-04-24T23:59:59.000Z

    Glasses with the chemical composition 35Li{sub 2}O-(45-x)V{sub 2}O{sub 5?}20PbO-xTeO{sub 2} (where x = 2.5, 5, 7.5, 10, 15 mol %) have prepared by conventional melt quenching method. The electrical conductivity of Li{sup +} ion conducting lead vanadium telluride glass samples has been carried out both as a function of temperature and frequency in the temperature range 503K-563K and over frequencies 40 Hz to 10 MHz. The electronic conduction has been observed in the present systems. When these samples annealed around 400°C for 2hour become the glass ceramic, which also shows increase tendency of conductivity. SEM confines glass and glass ceramic nature of the prepared samples.

  19. In situ characterization of nanoscale catalysts during anodic redox processes

    SciTech Connect (OSTI)

    Sharma, Renu [National Institute of Standards and Technology] National Institute of Standards and Technology; Crozier, Peter [Arizona State University] Arizona State University; Adams, James [Arizona State University] Arizona State University

    2013-09-19T23:59:59.000Z

    Controlling the structure and composition of the anode is critical to achieving high efficiency and good long-term performance. In addition to being a mixed electronic and ionic conductor, the ideal anode material should act as an efficient catalyst for oxidizing hydrogen, carbon monoxide and dry hydrocarbons without de-activating through either sintering or coking. It is also important to develop novel anode materials that can operate at lower temperatures to reduce costs and minimized materials failure associated with high temperature cycling. We proposed to synthesize and characterize novel anode cermets materials based on ceria doped with Pr and/or Gd together with either a Ni or Cu metallic components. Ceria is a good oxidation catalyst and is an ionic conductor at room temperature. Doping it with trivalent rare earths such as Pr or Gd retards sintering and makes it a mixed ion conductor (ionic and electronic). We have developed a fundamental scientific understanding of the behavior of the cermet material under reaction conditions by following the catalytic oxidation process at the atomic scale using a powerful Environmental Scanning Transmission Electron Microscope (ESTEM). The ESTEM allowed in situ monitoring of structural, chemical and morphological changes occurring at the cermet under conditions approximating that of typical fuel-cell operation. Density functional calculations were employed to determine the underlying mechanisms and reaction pathways during anode oxidation reactions. The dynamic behavior of nanoscale catalytic oxidation of hydrogen and methane were used to determine: ? Fundamental processes during anodic reactions in hydrogen and carbonaceous atmospheres ? Interfacial effects between metal particles and doped ceria ? Kinetics of redox reaction in the anode material

  20. Structural insights into the modulation of the redox properties of two Geobacter sulfurreducens homologous triheme cytochromes.

    SciTech Connect (OSTI)

    Morgado, L.; Bruix, M.; Orshonsky, V.; Londer, Y. Y.; Duke, N. E. C.; Yang, X.; Pokkuluri, P. R.; Schiffer, M.; Salgueiro, C. A.; Biosciences Division; Univ. Nova de Lisboa; Insti. de Quimica-Fisica

    2008-09-01T23:59:59.000Z

    The redox properties of a periplasmic triheme cytochrome, PpcB from Geobacter sulfurreducens, were studied by NMR and visible spectroscopy. The structure of PpcB was determined by X-ray diffraction. PpcB is homologous to PpcA (77% sequence identity), which mediates cytoplasmic electron transfer to extracellular acceptors and is crucial in the bioenergetic metabolism of Geobacter spp. The heme core structure of PpcB in solution, probed by 2D-NMR, was compared to that of PpcA. The results showed that the heme core structures of PpcB and PpcA in solution are similar, in contrast to their crystal structures where the heme cores of the two proteins differ from each other. NMR redox titrations were carried out for both proteins and the order of oxidation of the heme groups was determined. The microscopic properties of PpcB and PpcA redox centers showed important differences: (1) the order in which hemes become oxidized is III-I-IV for PpcB, as opposed to I-IV-III for PpcA; (2) the redox-Bohr effect is also different in the two proteins. The different redox features observed between PpcB and PpcA suggest that each protein uniquely modulates the properties of their co-factors to assure effectiveness in their respective metabolic pathways. The origins of the observed differences are discussed.

  1. Semiconductor-metal phase transition of vanadium dioxide nanostructures on silicon substrate: Applications for thermal control of spacecraft

    SciTech Connect (OSTI)

    Leahu, G. L., E-mail: roberto.livoti@uniroma1.it; Li Voti, R., E-mail: roberto.livoti@uniroma1.it; Larciprete, M. C., E-mail: roberto.livoti@uniroma1.it; Belardini, A., E-mail: roberto.livoti@uniroma1.it; Mura, F., E-mail: roberto.livoti@uniroma1.it; Sibilia, C.; Bertolotti, M. [Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, Via A. Scarpa 16 00161 Roma (Italy); Fratoddi, I. [Dipartimento di Chimica, Sapienza Università di Roma, Piazzale A. Moro, Roma (Italy)

    2014-06-19T23:59:59.000Z

    We present a detailed infrared study of the semiconductor-to-metal transition (SMT) in a vanadium dioxide (VO2) film deposited on silicon wafer. The VO2 phase transition is studied in the mid-infrared (MIR) region by analyzing the transmittance and the reflectance measurements, and the calculated emissivity. The temperature behaviour of the emissivity during the SMT put into evidence the phenomenon of the anomalous absorption in VO2 which has been explained by applying the Maxwell Garnett effective medium approximation theory, together with a strong hysteresis phenomenon, both useful to design tunable thermal devices to be applied for the thermal control of spacecraft. We have also applied the photothermal radiometry in order to study the changes in the modulated emissivity induced by laser. Experimental results show how the use of these techniques represent a good tool for a quantitative measurement of the optothermal properties of vanadium dioxide based structures.

  2. Solid polymer electrolyte electrochemical storage cell containing a redox shuttle additive for overcharge protection

    DOE Patents [OSTI]

    Richardson, Thomas J. (Oakland, CA); Ross, Philip N. (Moraga, CA)

    1999-01-01T23:59:59.000Z

    A class of organic redox shuttle additives is described, preferably comprising nitrogen-containing aromatics compounds, which can be used in a high temperature (85.degree. C. or higher) electrochemical storage cell comprising a positive electrode, a negative electrode, and a solid polymer electrolyte to provide overcharge protection to the cell. The organic redox additives or shuttles are characterized by a high diffusion coefficient of at least 2.1.times.10.sup.-8 cm.sup.2 /second and a high onset potential of 2.5 volts or higher. Examples of such organic redox shuttle additives include an alkali metal salt of 1,2,4-triazole, an alkali metal salt of imidazole, 2,3,5,6-tetramethylpyrazine, 1,3,5-tricyanobenzene, and a dialkali metal salt of 3-4-dihydroxy-3-cyclobutene-1,2-dione.

  3. Single-crystal structure of vanadium-doped La{sub 2}Mo{sub 2}O{sub 9}

    SciTech Connect (OSTI)

    Alekseeva, O. A., E-mail: olalex@ns.crys.ras.ru; Antipin, A. M. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Gagor, A.; Pietraszko, A. [Polish Academy of Sciences, Trzebiatowski Institute of Low Temperature and Structure Research (Poland)] [Polish Academy of Sciences, Trzebiatowski Institute of Low Temperature and Structure Research (Poland); Novikova, N. E.; Sorokina, N. I. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)] [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Kharitonova, E. P.; Voronkova, V. I. [Moscow State University (Russian Federation)] [Moscow State University (Russian Federation)

    2013-11-15T23:59:59.000Z

    A high-precision X-ray diffraction study of single crystals of two compositions-La{sub 2}Mo{sub 1.78}V{sub 0.22}O{sub 8.89} and La{sub 2}Mo{sub 1.64}V{sub 0.36}O{sub 8.82}-was performed. In the vanadium-doped compounds, as in the structure of the metastable {beta}{sub ms} phase of pure La{sub 2}Mo{sub 2}O{sub 9}, the La and Mo atoms and one of the three oxygen atoms are displaced from the threefold axis, on which they are located in the high-temperature {beta} phase. The structure contains two partially occupied oxygen sites. It was shown that molybdenum atoms are partially replaced by vanadium atoms, which are not involved in the disordering, are located on the threefold axis, and are shifted toward one of the oxygen atoms. This is consistent with the temperature-induced changes in the structure of La{sub 2}Mo{sub 2}O{sub 9} and the changes in the properties of these crystals caused by the introduction of vanadium atoms into the structure.

  4. Characterization of protein redox dynamics induced during light-to-dark transitions and nutrient limitation in cyanobacteria

    SciTech Connect (OSTI)

    Ansong, Charles; Sadler, Natalie C.; Hill, Eric A.; Lewis, Michael P.; Zink, Erika M.; Smith, Richard D.; Beliaev, Alex S.; Konopka, Allan; Wright, Aaron T.

    2014-07-03T23:59:59.000Z

    Protein redox chemistry constitutes a major void in knowledge pertaining to photoautotrophic system regulation and signaling processes. We have employed a chemical biology approach to analyze redox sensitive proteins in live Synechococcus sp. PCC 7002 cells in both light and dark periods, and to understand how cellular redox balance is disrupted during nutrient perturbation. The present work identified several novel putative redox-sensitive proteins that are involved in the generation of reductant, macromolecule synthesis, and carbon flux through central metabolic pathways, and may be involved in cell signaling and response mechanisms. Furthermore, our research suggests that dynamic redox changes in response to specific nutrient limitations contribute to the regulatory changes driven by a shift from light to dark. Taken together, these results contribute to the high-level understanding of post-translational mechanisms regulating flux distributions and therefore present potential metabolic engineering targets for redirecting carbon towards biofuel precursors.

  5. Carbon-carbon bond cleavage of 1,2-hydroxy ethers b7 vanadium(V) dipicolinate complexes

    SciTech Connect (OSTI)

    Hanson, Susan K [Los Alamos National Laboratory; Gordon, John C [Los Alamos National Laboratory; Thorn, David L [Los Alamos National Laboratory; Scott, Brian L [Los Alamos National Laboratory; Baker, R Tom [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    The development of alternatives to current petroleum-based fuels and chemicals is becoming increasingly important due to concerns over climate change, growing world energy demand, and energy security issues. Using non-food derived biomass to produce renewable feedstocks for chemicals and fuels is a particularly attractive possibility. However, the majority of biomass is in the form of lignocellulose, which is often not fully utilized due to difficulties associated with breaking down both lignin and cellulose. Recently, a number of methods have been reported to transform cellulose directly into more valuable materials such as glucose, sorbitol, 5-(chloromethyl)furfural, and ethylene glycol. Less progress has been made with selective transformations of lignin, which is typically treated in paper and forest industries by kraft pulping (sodium hydroxide/sodium sulfide) or incineration. Our group has begun investigating aerobic oxidative C-C bond cleavage catalyzed by dipicolinate vanadium complexes, with the idea that a selective C-C cleavage reaction of this type could be used to produce valuable chemicals or intermediates from cellulose or lignin. Lignin is a randomized polymer containing methoxylated phenoxy propanol units. A number of different linkages occur naturally; one of the most prevalent is the {beta}-O-4 linkage shown in Figure 1, containing a C-C bond with 1,2-hydroxy ether substituents. While the oxidative C-C bond cleavage of 1,2-diols has been reported for a number of metals, including vanadium, iron, manganese, ruthenium, and polyoxometalate complexes, C-C bond cleavage of 1,2-hydroxy ethers is much less common. We report herein vanadium-mediated cleavage of C-C bonds between alcohol and ether functionalities in several lignin model complexes. In order to explore the scope and potential of vanadium complexes to effect oxidative C-C bond cleavage in 1,2-hydroxy ethers, we examined the reactivity of the lignin model complexes pinacol monomethyl ether (A), 2-phenoxyethanol (B), and 1,2-diphenyl-2-methoxyethanol (C) (Figure 1). Reaction of (dipic)V{sup V}(O)O{sup i}Pr (1a) or (dipic)V{sup v}(O)OEt (lb) with A, B, or C in acetonitrile yielded new vanadium(V) complexes where the alcohol-ether ligand was bound in a chelating fashion. From the reaction of 1b with pinacol monomethyl ether (A) in acetonitrile solution, (dipic)V{sup v}(O)(pinOMe) (2) (PinOMe = 2,3-dimethyl-3-methoxy-2-butanoxide) was isolated in 61 % yield. Reaction of 1b with 2-phenoxyethanol (B) in acetonitrile gave the new complex (dipic)V{sup v}(O)(OPE) (3) (OPE = 2-phenoxyethoxide), which was isolated in 76% yield. In a similar fashion, 1a reacted with 1,2-diphenyl-2-methoxyethanol (C) to give (dipic)V(O)(DPME) (4) (DPME = 1,2-diphenyl-2-methoxyethoxide), which was isolated in 39% yield. Complexes 2, 3, and 4 were characterized by {sup 1}H NMR and IR spectroscopy, elemental analysis, and X-ray crystallography. Compared to the previously reported vanadium(V) pinacolate complex (dipic)V(O)(pinOH) the X-ray structure of complex 2 reveals a slightly shorter V = O bond, 1.573(2) {angstrom} vs 1.588(2) {angstrom} for the pinOH structure. Complexes 3 and 4 display similar vanadium oxo bond distances of 1.568(2) {angstrom} and 1.576(2) {angstrom}, respectively. All three complexes show longer bonds to the ether-oxygen trans to the oxo (2.388(2) {angstrom} for 2, 2.547(2) {angstrom} for 3, and 2.438(2) {angstrom} for 4) than to the hydroxy-oxygen in the pinOH structure (2.252(2) {angstrom}).

  6. Final Technical Report

    SciTech Connect (OSTI)

    Logan, Jesse, L; Witmer, Dennis, PhD

    2012-07-29T23:59:59.000Z

    The overall goal of this project was to design, evaluate, and engineer a Vanadium Red-Ox Flow Battery's integration into an existing wind site and micro-grid environment to determine if it is possible to achieve a fifteen percent reduction of diesel fuel usage during periods of peak load and otherwise stabilize the grid in potential high wind penetration systems. The bulk of the work was done by modeling the existing hybrid wind-diesel system and the proposed system with added flow battery storage. The flow battery was changed from a Vanadium Red-Ox to a Zinc Bromine flow battery by a different manufacturer during the modeling process. Several complications arose, but modeling proved to be successful and is ongoing. The development of a modeling platform for flow battery energy storage is a key element in evaluating both economic benefits and dispatch strategies for high penetration in micro-grid wind-diesel systems.

  7. Redox reactions of reduced flavin mononucleotide (FMN), riboflavin (RBF), and anthraquinone-2,6-disulfonate (AQDS) with ferrihydrite and lepidocrocite

    SciTech Connect (OSTI)

    Shi, Zhi; Zachara, John M.; Shi, Liang; Wang, Zheming; Moore, Dean A.; Kennedy, David W.; Fredrickson, Jim K.

    2012-11-01T23:59:59.000Z

    Flavins are secreted by the dissimilatory iron-reducing bacterium Shewanella and can function as endogenous electron transfer mediators (ETM). In order to assess the potential importance of flavins in Fe(III) bioreduction, we investigated the redox reaction kinetics of reduced flavins (FMNH2 and RBFH2) with ferrihydrite and lepidocrocite. The organic reductants rapidly reduced and dissolved ferrihydrite and lepidocrocite in the pH range 4-8. The rate constant k for 2-line ferrihydrite reductive dissolution by FMNH2 was 87.5 ? 3.5 M-1?s-1 at pH 7.0 in batch reactors, and the k was similar for RBFH2. For lepidocrocite, the k was 500 ? 61 M-1?s-1 for FMNH2, and 236 ? 22 M-1?s-1 for RBFH2. The surface area normalized initial reaction rates (ra) were between 0.08 and 77 ?moles?m-2?s-1 for various conditions in stopped-flow experiments. Initial rates (ro) were first-order with respect to Fe(III) oxide concentration, and ra increased with decreasing pH. Poorly crystalline 2-line ferrihydrite yielded the highest ra, followed by more crystalline 6-line ferrihydrite, and crystalline lepidocrocite. Compared to a previous whole-cell study with Shewanella oneidensis strain MR-1, our findings suggest that ETM reduction by the Mtr pathway coupled to lactate oxidation are rate limiting, rather than heterogeneous electron transfer to the Fe(III) oxide.

  8. Redox-linked conformational changes of a multiheme cytochrome from Geobacter sulfurreducens

    SciTech Connect (OSTI)

    Morgado, Leonor [Requimte - CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Bruix, Marta [Departamento de Espectroscopia y Estructura Molecular, Instituto de Quimica-Fisica 'Rocasolano', CSIC, Serrano 119, 28006 Madrid (Spain); Londer, Yuri Y. [Biosciences Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Pokkuluri, P. Raj [Biosciences Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Schiffer, Marianne [Biosciences Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Salgueiro, Carlos A. [Requimte - CQFB, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)]. E-mail: csalgueiro@dq.fct.unl.pt

    2007-08-17T23:59:59.000Z

    Multiheme c-type cytochromes from members of the Desulfovibrionacea and Geobactereacea families play crucial roles in the bioenergetics of these microorganisms. Thermodynamic studies using NMR and visible spectroscopic techniques on tetraheme cytochromes c {sub 3} isolated from Desulfovibrio spp. and more recently on a triheme cytochrome from Geobacter sulfurreducens showed that the properties of each redox centre are modulated by the neighbouring redox centres enabling these proteins to perform energy transduction and thus contributing to cellular energy conservation. Electron/proton transfer coupling relies on redox-linked conformational changes that were addressed for some multiheme cytochromes from the comparison of protein structure of fully reduced and fully oxidised forms. In this work, we identify for the first time in a multiheme cytochrome the simultaneous presence of two different conformations in solution. This was achieved by probing the different oxidation stages of a triheme cytochrome isolated from G. sulfurreducens using 2D-NMR techniques. The results presented here will be the foundations to evaluate the modulation of the redox centres properties by conformational changes that occur during the reoxidation of a multiheme protein.

  9. Microfabricated capillary electrophoresis chip and method for simultaneously detecting multiple redox labels

    DOE Patents [OSTI]

    Mathies, Richard A. (Moraga, CA); Singhal, Pankaj (Berkeley, CA); Xie, Jin (Walnut Creek, CA); Glazer, Alexander N. (Orinda, CA)

    2002-01-01T23:59:59.000Z

    This invention relates to a microfabricated capillary electrophoresis chip for detecting multiple redox-active labels simultaneously using a matrix coding scheme and to a method of selectively labeling analytes for simultaneous electrochemical detection of multiple label-analyte conjugates after electrophoretic or chromatographic separation.

  10. J.F. ALLEN, K. ALEXCIEV AND G. HAKANSSON Regulation by redox signalling

    E-Print Network [OSTI]

    Allen, John F.

    ,5] confirms this suspicion, and shows that redox control over photo- synthesis genes is exerted by two new', phosphorylated on aspar- tate by transfer of a phosphate from its partner, RegB. RegB is a 'sensor kinase; the genes reside in just two operons. It has long been known that the photo- synthetic apparatus

  11. Redox Regulation of the Nutrient-sensitive Raptor-mTOR Pathway and Complex*

    E-Print Network [OSTI]

    Sabatini, David M.

    Redox Regulation of the Nutrient-sensitive Raptor-mTOR Pathway and Complex* Received, Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts 02142 The raptor-mTOR protein complex is a key component of a nutrient-sensitive signaling pathway

  12. Redox states of Desulfovibrio vulgaris DsrC, a key protein in dissimilatory sulfite reduction

    SciTech Connect (OSTI)

    Venceslau, Sofia S. [Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras (Portugal)] [Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras (Portugal); Cort, John R.; Baker, Erin S. [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352 (United States)] [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Chu, Rosalie K.; Robinson, Errol W. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352 (United States)] [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Dahl, Christiane [Institut für Mikrobiologie and Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Meckenheimer Allee 168, D-53115 Bonn (Germany)] [Institut für Mikrobiologie and Biotechnologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Meckenheimer Allee 168, D-53115 Bonn (Germany); Saraiva, Lígia M. [Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras (Portugal)] [Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras (Portugal); Pereira, Inês A.C., E-mail: ipereira@itqb.unl.pt [Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras (Portugal)

    2013-11-29T23:59:59.000Z

    Highlights: •DsrC is known to interact with the dissimilatory sulfite reductase enzyme (DsrAB). •We show that, however, most cellular DsrC is not associated with DsrAB. •A gel-shift assay was developed that allows monitoring of the DsrC redox state. •The DsrC intramolecularly oxidized state could only be produced by arginine treatment. -- Abstract: Dissimilatory reduction of sulfite is carried out by the siroheme enzyme DsrAB, with the involvement of the protein DsrC, which has two conserved redox-active cysteines. DsrC was initially believed to be a third subunit of DsrAB. Here, we report a study of the distribution of DsrC in cell extracts to show that, in the model sulfate reducer Desulfovibrio vulgaris, the majority of DsrC is not associated with DsrAB and is thus free to interact with other proteins. In addition, we developed a cysteine-labelling gel-shift assay to monitor the DsrC redox state and behaviour, and procedures to produce the different redox forms. The oxidized state of DsrC with an intramolecular disulfide bond, which is proposed to be a key metabolic intermediate, could be successfully produced for the first time by treatment with arginine.

  13. Quantification of rapid environmental redox processes with quick-scanning x-ray absorption

    E-Print Network [OSTI]

    Sparks, Donald L.

    Quantification of rapid environmental redox processes with quick-scanning x-ray absorption. Here we apply quick-scanning x-ray absorption spectroscopy (Q-XAS), at sub-second time that can be measured using x-ray absorption spectroscopy. arsenic extended x-ray absorption fine structure

  14. Nanostructured bilayered vanadium oxide electrodes for rechargeable sodium-ion batteries.

    SciTech Connect (OSTI)

    Tepavcevic, S.; Xiong, H.; Stamenkovic, V.R.; Zuo, X.; Balasubramanian, M.; Prakapenka, V.B.; Johnson, C.S.; Rajh, T. (Accelerator Systems Division (APS)); ( CNM); ( MSD); (University of Chicago)

    2012-01-01T23:59:59.000Z

    Tailoring nanoarchitecture of materials offers unprecedented opportunities in utilization of their functional properties. Nanostructures of vanadium oxide, synthesized by electrochemical deposition, are studied as a cathode material for rechargeable Na-ion batteries. Ex situ and in situ synchrotron characterizations revealed the presence of an electrochemically responsive bilayered structure with adjustable intralayer spacing that accommodates intercalation of Na{sup +} ions. Sodium intake induces organization of overall structure with appearance of both long- and short-range order, while deintercalation is accompanied with the loss of long-range order, whereas short-range order is preserved. Nanostructured electrodes achieve theoretical reversible capacity for Na{sub 2}V{sub 2}O{sub 5} stoichiometry of 250 mAh/g. The stability evaluation during charge-discharge cycles at room temperature revealed an efficient 3 V cathode material with superb performance: energy density of {approx}760 Wh/kg and power density of 1200 W/kg. These results demonstrate feasibility of development of the ambient temperature Na-ion rechargeable batteries by employment of electrodes with tailored nanoarchitectures.

  15. The Integration of a Structural Water Gas Shift Catalyst with a Vanadium Alloy Hydrogen Transport Device

    SciTech Connect (OSTI)

    Barton, Thomas; Argyle, Morris; Popa, Tiberiu

    2009-06-30T23:59:59.000Z

    This project is in response to a requirement for a system that combines water gas shift technology with separation technology for coal derived synthesis gas. The justification of such a system would be improved efficiency for the overall hydrogen production. By removing hydrogen from the synthesis gas stream, the water gas shift equilibrium would force more carbon monoxide to carbon dioxide and maximize the total hydrogen produced. Additional benefit would derive from the reduction in capital cost of plant by the removal of one step in the process by integrating water gas shift with the membrane separation device. The answer turns out to be that the integration of hydrogen separation and water gas shift catalysis is possible and desirable. There are no significant roadblocks to that combination of technologies. The problem becomes one of design and selection of materials to optimize, or at least maximize performance of the two integrated steps. A goal of the project was to investigate the effects of alloying elements on the performance of vanadium membranes with respect to hydrogen flux and fabricability. Vanadium was chosen as a compromise between performance and cost. It is clear that the vanadium alloys for this application can be produced, but the approach is not simple and the results inconsistent. For any future contracts, large single batches of alloy would be obtained and rolled with larger facilities to produce the most consistent thin foils possible. Brazing was identified as a very likely choice for sealing the membranes to structural components. As alloying was beneficial to hydrogen transport, it became important to identify where those alloying elements might be detrimental to brazing. Cataloging positive and negative alloying effects was a significant portion of the initial project work on vanadium alloying. A water gas shift catalyst with ceramic like structural characteristics was the second large goal of the project. Alumina was added as a component of conventional high temperature water gas shift iron oxide based catalysts. The catalysts contained Fe-Al-Cr-Cu-O and were synthesized by co-precipitation. A series of catalysts were prepared with 5 to 50 wt% Al2O3, with 8 wt% Cr2O3, 4 wt% CuO, and the balance Fe2O3. All of the catalysts were compared to a reference WGS catalyst (88 wt% FeOx, 8 wt% Cr2O3, and 4 wt% CuO) with no alumina. Alumina addition to conventional high temperature water gas shift catalysts at concentrations of approximately 15 wt% increased CO conversion rates and increase thermal stability. A series of high temperature water gas shift catalysts containing iron, chromia, and copper oxides were prepared with small amounts of added ceria in the system Fe-Cr-Cu-Ce-O. The catalysts were also tested kinetically under WGS conditions. 2-4 wt% ceria addition (at the expense of the iron oxide content) resulted in increased reaction rates (from 22-32% higher) compared to the reference catalyst. The project goal of a 10,000 liter per day WGS-membrane reactor was achieved by a device operating on coal derived syngas containing significant amounts of carbon monoxide and hydrogen sulfide. The membrane flux was equivalent to 52 scfh/ft2 based on a 600 psi syngas inlet pressure and corresponded to membranes costing $191 per square foot. Over 40 hours of iv exposure time to syngas has been achieved for a double membrane reactor. Two modules of the Chart reactor were tested under coal syngas for over 75 hours with a single module tested for 50 hours. The permeance values for the Chart membranes were similar to the REB reactor though total flux was reduced due to significantly thicker membranes. Overall testing of membrane reactors on coal derived syngas was over 115 hours for all reactors tested. Testing of the REB double membrane device exceeded 40 hours. Performance of the double membrane reactor has been similar to the results for the single reactor with good maintenance of flux even after these long exposures to hydrogen sulfide. Of special interest is that the flux is highest at the start of each e

  16. Effect of Reducing Groundwater on the Retardation of Redox-Sensitive Radionuclides

    SciTech Connect (OSTI)

    Hu, Q; Zavarin, M; Rose, T P

    2008-04-21T23:59:59.000Z

    Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions used during these experiments were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. Under atmospheric (oxidizing) conditions, the radionuclide distribution coefficients varied with the mineralogical composition of the sorbent and the water chemistry. Under reducing conditions, distribution coefficients showed marked increases for {sup 99}Tc and {sup 237}Np in devitrified tuff, but much smaller variations in alluvium, carbonate rock, and zeolitic tuff. This effect was particularly important for {sup 99}Tc, which tends to be mobile under oxidizing conditions. Unlike other redox-sensitive radionuclides, iodine sorption may decrease under reducing conditions when I{sup -} is the predominant species. Overall, sorption of U to alluvium, devitrified tuff, and zeolitic tuff under atmospheric conditions was less than in the glove-box tests. However, the mildly reducing conditions achieved here were not likely to result in substantial U(VI) reduction to U(IV). Sorption of Pu was not affected by the decreasing redox conditions achieved in this study, as the predominant sorbed Pu species in all conditions was expected to be the low-solubility and strongly sorbing Pu(OH){sub 4}. Depending on the aquifer lithology, the occurrence of reducing conditions along a groundwater flowpath could potentially contribute to the retardation of redox-sensitive radionuclides {sup 99}Tc and {sup 237}Np, which are commonly identified as long-term dose contributors in the risk assessment in various nuclear facilities.

  17. In Situ Redox Manipulation Proof-of-Principle Test at the Fort Lewis Logistics Center: Final Report

    SciTech Connect (OSTI)

    VR Vermeul; MD Williams; JC Evans; JE Szecsody; BN Bjornstad; TL Liikala

    2000-10-25T23:59:59.000Z

    Pacific Northwest National Laboratory (PNNL) conducted a proof-of-principle test at the Fort Lewis Logistics Center to determine the feasibility of using the In Situ Redox Manipulation (ISRM) technology for remediating groundwater contaminated with dissolved trichloroethylene (TCE). ISRM creates a permeable treatment zone in the subsurface to remediate redox-sensitive contaminants in groundwater. The permeable treatment zone is formed by injecting a chemical reducing agent (sodium dithionite with pH buffers) into the aquifer through a well to reduce the naturally occurring ferric iron in the sediments to ferrous iron. Once the reducing agent is injected and given sufficient time to react with aquifer sediments, residual chemicals and reaction products are withdrawn from the aquifer through the same well used for the injection. Redox-sensitive contaminants such as TCE, moving through the treatment zone under natural groundwater flow conditions, are destroyed. TCE is degraded via reductive dechlorination within the ISRM treatment zone to benign degradation products (i.e., acetylene, ethylene). Prior to the proof-of-principle field test, the ISRM technology was successfully demonstrated in laboratory experiments for the reductive dechlorination of dissolved TCE using sediments from the Fort Lewis site. The Logistics Center was placed on the National Priorities List in December 1989 because of TCE contamination in groundwater beneath the site. A Federal Facilities Agreement between the Army, the U.S. Environmental Protection Agency, and the Washington State Department of Ecology became effective in January 1990, and a Record of Decision (ROD) was signed in September 1990. The major components of the ROD included installation of two pump-and-treat systems for the upper aquifer and further investigation of the lower aquifer and other potential sources of contamination. The pump-and-treat systems became operational in August 1995. Fort Lewis asked PNNL to provide technical support in accelerating Installation Restoration Program site remediation and significantly reducing site life-cycle costs at the Logistics Center. In support of this program, ISRM was selected as an innovative technology for bench and field-scale demonstration. Emplacement of the ISRM treatment zone was accomplished through a series of four separate dithionite injection tests conducted between November 10, 1998 and March 29,2000. An extensive program of chemical monitoring was also performed before, during, and after each injection to evaluate the performance of ISRM. Prior to emplacement of the ISRM treatment zone, the site was extensively characterized with respect to geologic, hydrologic, and geochemical properties. Sediment core samples collected for the characterization studies were analyzed in bench-scale column tests at PNNL to determine reducible iron content. These site-specific hydrogeologic and geochemical data were used to develop the emplacement design of the pilot-scale (i.e., single injection well) ISRM treatment zone. Performance data obtained from the proof-of-principle test indicate that field-scale reductive dechlorination of TCE using the ISRM technology is feasible. A treatment zone was created in the subsurface that reduced TCE concentrations as much as 92% on the downgradient side of the reduced zone, from a background concentration of approximately 140 ppb to approximately 11 ppb. The appearance of the principal degradation product, acetylene, also confirmed that TCE destruction was occurring. Analysis of sediment samples collected from post-test boreholes showed a high degree of iron reduction, which helped to confirm the effectiveness of the treatment zone emplacement. Another important goal of the testing program was to provide assurances that chemical treatment of the subsurface did not result in undesirable secondary effects, including formation of toxic TCE degradation products, mobilization of trace elements, and degradation of hydraulic performance. Results obtained from the Fort Lewis ISRM proof-of-principle test, which are c

  18. Determination of arsenic, molybdenum, uranium and vanadium in seawater by neutron activation analysis after preconcentration by colloid flotation

    SciTech Connect (OSTI)

    Murthy, R.S.S.; Ryan, D.E.

    1983-04-01T23:59:59.000Z

    Colloid flotation of arsenic, molybdenum, uranium, and vanadium on hydrous iron(III) oxide permits rapid collection of the precipitate for neutron activation analysis. The precipitate is floated, in the presence of sodium dodecyl sulfate and tiny nitrogen bubbles, from 1 L of seawater at pH 5.7 +/- 0.2. Except for uranium, recoveries are better than 95%; about 75% of the uranium was recovered. Selenium(IV) and tungsten(VI) can be similarly collected but their natural concentration levels in seawater are below detection limits for 1 L volumes.

  19. First-principle study of geometric stabilities, electronic and magnetic properties of low coverage vanadium adsorption on graphene

    SciTech Connect (OSTI)

    Abdullahi, Yusuf Zuntu [Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia and Department of Physics, Faculty of Science, Kaduna State University, P.M.B. 2339, Kaduna State (Nigeria); Rahman, Md. Mahmudur, E-mail: mahmudur@upm.edu.my [Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Zainuddin, H. [Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia and Institute for Mathematical Research, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Abubakar, Shamsu [Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia and Department of Physics, Faculty of Science, Yobe State University, P.M.B. 1144, Yobe State (Nigeria)

    2014-03-05T23:59:59.000Z

    Stable geometries, electronic and magnetic properties of low coverage vanadium (V) atoms adsorption on graphene sheet have been investigated by first principles calculations, using generalized gradient approximation. Calculation shows that center of the ring is energetically favorable for both V adatom and perpendicular dimer after relaxation. Moreover, the proportion of orbital contribution of C-V bonding are mainly dominated by 2p{sub z} orbital of C and partially occupied by the 3d like states of V. It is also found that the low coverage V atom adsorbed graphene system is metallic and magnetic, and has demonstrated additional hint on its usefulness in magnetic devices.

  20. Factors influencing charge capacity of vanadium pentoxide thin films during lithium ion intercalation/deintercalation cycles

    SciTech Connect (OSTI)

    Alamarguy, D.; Castle, J. E.; Ibris, N.; Salvi, A. M. [University of Surrey, Guildford GU2 7XH (United Kingdom); Dipartimento di Chimica, Universita degli Studi della Basilicata, Potenza, Via N. Sauro, 85-85100 (Italy)

    2007-11-15T23:59:59.000Z

    The intercalation of vanadium pentoxide by lithium ions leads to a change in optical properties, a process that is of value in thin-film electrochromic devices. In this study, films of V{sub 2}O{sub 5}, deposited on indium tin oxide (ITO) glass coupons by a sol-gel process, were challenged by increasing numbers of charge-discharge cycles ranging from 72 to 589 full cycles. The samples were characterized by x-ray photoelectron spectroscopy (XPS) and then examined in the deintercalated state by time-of-flight secondary ion mass spectroscopy (SIMS). XPS enabled measurement of the thickness and composition of the solid-electrolyte interface and provided evidence of the residual V{sup 4+} concentration within the top few nanometers of the surface. The SIMS profile gave direct information on the thickness of the films and on the thickness loss caused by rinsing the samples after the electrochemical exposure. Determination, by SIMS, of the concentration of lithium ions has enabled a correction to be made for the amount of inactive material within the electrochemically active region of the film. The SIMS depth profiles for lithium in the four samples are similar, with a marked buildup of Li at the interface with the ITO. This interphase zone had a thickness of {approx}27 nm and was electrochemically inactive, enabling a further correction to be made. Thus, by means of the XPS and the SIMS results the chemistry and thickness of the films could be fully characterized. The remaining inconsistency between capacity (between 35% and 100% of the anticipated charge) and number of cycles is ascribed to edge effects arising from the method used for production of the coupons.

  1. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  2. Redox states of Desulfovibrio vulgaris DsrC, a key protein in dissimilatory sulfite reduction

    SciTech Connect (OSTI)

    Venceslau, Sofia S.; Cort, John R.; Baker, Erin Shammel; Chu, Rosalie K.; Robinson, Errol W.; Dahl, Christiane; Saraiva, Ligia M.; Pereira, Ines Ac

    2013-11-29T23:59:59.000Z

    Dissimilatory reduction of sulfite is carried out by the siroheme enzyme DsrAB, with the involvement of the protein DsrC having two conserved cysteine residues. Here, we report a study of the distribution of DsrC in cell extracts, a cysteine-labelling gel-shift assay to monitor its redox state and behaviour, and procedures to produce the different redox forms. We show that, in the model sulfate reducer Desulfovibrio vulgaris, the majority of DsrC is not associated with DsrAB and is thus free to interact with other proteins. In addition, we successfully produced DsrC with an intramolecular disulfide bond (oxidized state) by treatment with arginine.

  3. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19T23:59:59.000Z

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  4. Unveiling Surface Redox Charge Storage of Interacting Two-Dimensional Hetero-Nanosheets in Hierarchical Architectures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mahmood, Qasim [Department of Chemical Engineering, College of Engineering, Kyung Hee University (Republic of Korea); Bak, Seong-Min [Brookhaven National Laboratory (BNL), Upton, NY (United States); Kim, Min G. [Beamline Research Division, Pohang Accelerator Laboratory, Pohang (Republic of Korea); Yun, Sol [School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon (Republic of Korea); Yang, Xiao-Qing [Brookhaven National Laboratory (BNL), Upton, NY (United States); Shin, Hyeon S. [Department of Energy Engineering, Department of Chemistry, and Low Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology(UNIST) (Republic of Korea); Kim, Woo S. [Department of Chemical Engineering, College of Engineering, Kyung Hee University (Republic of Korea); Braun, Paul V. [Department of Materials Science and Engineering Materials Research Laboratory and Beckman Institute, University of Illinois at Urbana?Champaign, Urbana, Illinois (United States); Park, Ho S. [School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon (Republic of Korea)

    2015-04-08T23:59:59.000Z

    Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to the interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane W–S lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of W–W bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.

  5. Radiation-induced non-equilibrium redox chemistry of plutonium: implications for environmental migration

    SciTech Connect (OSTI)

    Haschke, J M; Siekhaus, W J

    2009-02-11T23:59:59.000Z

    Static concentrations of plutonium oxidation states in solution and at surfaces in oxide-water systems are identified as non-equilibrium steady states. These kinetically controlled systems are described by redox cycles based on irreversible disproportionation of Pu(IV), Pu(V), and Pu(VI) in OH-bridged intermediate complexes and at OH-covered oxide surfaces. Steady state is fixed by continuous redox cycles driven by radioactivity-promoted electron-transfer and energetically favorable reactions of Pu(III) and Pu(VII) disproportionation products with H2O. A model based on the redox cycles accounts for the high steady-state [Pu] coexisting with Pu(IV) hydrous oxide at pH 0-15 and for predominance of Pu(V) and Pu(VI) in solution. The steady-state [Pu] depends on pH and the surface area of oxide in solution, but not on the initial Pu oxidation state. PuO{sub 2+x} formation is attributed to high Pu(V) concentrations existing at water-exposed oxide surfaces. Results infer that migration of Pu in an aqueous environment is controlled by kinetic factors unique to that site and that the predominant oxidation states in solution are Pu(V) and Pu(VI).

  6. EVALUATION OF AMENDMENTS FOR MENDING THE INSITU REDOX MANIPULATION (ISRM) BARRIER

    SciTech Connect (OSTI)

    PETERSEN, S.W.

    2006-02-07T23:59:59.000Z

    In May of 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from DOE Headquarters EM-23 to provide a team of technical experts to evaluate likely chemical/biological amendments for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site. This request was a follow-on to an earlier request for assistance regarding the cause of chromium (Cr) breakthrough and recommendations for mending the barrier (March 2004 workshop). This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)] was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the ISRM technology, was installed at a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. Bench-scale and field-scale treatability tests were conducted to demonstrate proof-of principle and to estimate barrier longevity, calculated to be in excess of twenty years. However, several years after initial and secondary treatment, groundwater in approximately 17 wells has been found to contain elevated Cr concentrations. The March 2004 technical assistance team (TAT) identified potential causes of Cr breakthrough as likely related to physical and chemical heterogeneity within the aquifer (including loss of reductive capacity within preferential flow paths) and the presence of other oxidants (DO and nitrate) significantly affecting the reductive capacity of the treated aquifer. These aquifer characteristics may limit the ability of alternative amendments to extend the reducing capacity of the barrier. A 2001 Bechtel Hanford report and evaluation of the ISRM performance data and barrier longevity assessment corroborate the observations and findings of the March 2004 TAT. The March 2004 TAT recommended the collection of new aquifer characterization data in combination with the interpretation of existing data to develop a conceptual model of aquifer heterogeneity to enable design of the most appropriate barrier mending system. The current TAT was convened to examine the most promising amendment that could be applied to mend the ISRM barrier. The Technical Assistance Team (TAT) performed the following activities: (1) Evaluate the most appropriate single or combination of chemical/biological amendments suitable for increasing the reductive capacity of the ISRM barrier; (2) Evaluate the most practicable means of introducing chemical/biological amendments in the target zones along the current BRM barrier; (3) Provide recommendations for laboratory treatability-testing protocol development to evaluate the type and delivery mechanisms of amendments in the current ISRM barrier location. Sections of this report present analyses and recommendations of potential amendments and delivery options to improve performance of the ISRM barrier. The report covers the spectrum of passive barrier mending to chemical and biological amendments that have been shown to perform more efficiently in more active remedial design approaches. Because DOE/RL is considering significant aquifer characterization studies as additional time and cost investment to mending the barrier, the TAT strongly recommends that DOE/RL conduct cost-benefit analyses of alternative designs to mend the barrier. In this way, the value and extent of characterization studies, compared to passive amendment delivery, compared to engineering redesign, can be quantitatively estimated for decision-making purposes.

  7. 100-D Area In Situ Redox Treatability Test for Chromate-Contaminated Groundwater: FY 1998 Year-End Report

    SciTech Connect (OSTI)

    Williams, M.D.; Vermeul, V.R.; Szecsody, J.E.; Fruchter, J.S.; Cole, C.R.

    1999-04-15T23:59:59.000Z

    A treatability test was conducted for the In Situ Redox Manipulation (ISRM) technology at the US Department of Energy's Hanford, Washington 100D Area. The target contaminant was dissolved chromate [Cr(VI)] in groundwater. The ISRM technology involves creating a permeable subsurface treatment zone to reduce mobile chromate in groundwater to an insoluble form. The ISRM permeable treatment zone is created by reducing ferric iron [Fe(III)] to ferrous iron [Fe(II)] within the aquifer sediments. This is accomplished by injecting aqueous sodium dithionite into the aquifer and withdrawing the reaction products. The goal of the treatability test was to create a linear ISRM barrier by injecting sodium dithionite into five wells. Well installation and site characterization activities began in the spring of 1997. The first dithionite injection took place in September 1997. The results of this first injection were monitored through the spring of 1998; the remaining four dithionite injections were carried out in May through July of 1998. These five injections created a reduced zone in the Hanford unconfined aquifer 150 feet in length (perpendicular to groundwater flow) by 50 feet wide. The reduced zone extended over the thickness of the unconfined zone, which is approximately 15 feet. Analysis of recent groundwater sampling events shows that the concentrations of chromate [Cr(VI)] in groundwater in the reduced zone have been decreased from starting concentrations of approximately 900 ppb to below analytical detection limits (<7 ppb). Chromate concentrations are also declining in some downgradient monitoring wells. Laboratory analysis of iron in the soil indicates that the barrier should remain in place for approximately 20 to 25 years. These measurements will be confirmed by analysis of sediment cores in FY 1999.

  8. Experimental Verification of the Van Vleck Nature of Long-Range Ferromagnetic Order in the Vanadium-Doped Three-Dimensional Topological Insulator Sb[subscript 2]Te[subscript 3

    E-Print Network [OSTI]

    Li, Mingda

    We demonstrate by high resolution low temperature electron energy loss spectroscopy (EELS) measurements that the long range ferromagnetic (FM) order in the vanadium- (V-)doped topological insulator Sb[subscript 2]Te[subscript ...

  9. Redox buffered hydrofluoric acid etchant for the reduction of galvanic attack during release etching of MEMS devices having noble material films

    DOE Patents [OSTI]

    Hankins, Matthew G. (Albuquerque, NM)

    2009-10-06T23:59:59.000Z

    Etchant solutions comprising a redox buffer can be used during the release etch step to reduce damage to the structural layers of a MEMS device that has noble material films. A preferred redox buffer comprises a soluble thiophosphoric acid, ester, or salt that maintains the electrochemical potential of the etchant solution at a level that prevents oxidation of the structural material. Therefore, the redox buffer preferentially oxidizes in place of the structural material. The sacrificial redox buffer thereby protects the exposed structural layers while permitting the dissolution of sacrificial oxide layers during the release etch.

  10. Cooling Flows or Heating Flows?

    E-Print Network [OSTI]

    James Binney

    2003-10-08T23:59:59.000Z

    It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal stability of the AGN/cooling flow interaction are discussed. Collimation of the winds probably provides spatial stability. Temporal stability may be possible only for black holes with masses above a critical value. Both the failure of cooling flows to have adiabatic cores and the existence of X-ray cavities confirm the importance of collimated outflows. I quantify the scale of the convective flow that the AGN Hydra would need to drive if it balanced radiative inward flow by outward flow parallel to the jets. At least in Virgo any such flow must be confined to r<~20 kpc. Hydrodynamical simulations suggest that AGN outbursts cannot last longer than ~25 Myr. Data for four clusters with well studied X-ray cavities suggests that heating associated with cavity formation approximately balances radiative cooling. The role of cosmic infall and the mechanism of filament formation are briefly touched on.

  11. Hot gas desulfurization with sorbents containing oxides of zinc, iron, vanadium and copper. Quarterly technical progress report, July 1992

    SciTech Connect (OSTI)

    Akyurtlu, A.; Akyurtlu, J.F.

    1992-09-01T23:59:59.000Z

    The main objective of this research is to evaluate the desulfurization performance of novel sorbents consisting of different combinations of zinc, iron, vanadium and copper oxides; and to develop a sorbent which can reduce H{sub 2}S levels to less than 1 ppmv, which can stabilize zinc, making operations above 650{degrees}C possible, and which can produce economically recoverable amounts of elemental sulfur during regeneration. This objective will be accomplished by evaluating the sorbent performance using fixed-bed and TGA experiments supported by sorbent characterization at various reaction extents. In the seventh quarter, the screening of the promoted sorbents in the packed bed reactor was continued. The results of this work were presented at the 1992 University Coal Research Contractors, Review Conference at Pittsburgh, PA.

  12. Visible light photocatalytic degradation of 4-chlorophenol using vanadium and nitrogen co-doped TiO{sub 2}

    SciTech Connect (OSTI)

    Jaiswal, R.; Kothari, D. C. [Department of Physics, University of Mumbai, Vidyanagari, Santacruz (E), Mumbai 400 098 (India); Patel, N.; Miotello, A. [Dipartimento di Fisica, Universita degli Studi di Trento, I-38123 Povo ( Trento) (Italy)

    2013-02-05T23:59:59.000Z

    Vanadium and Nitrogen were codoped in TiO{sub 2} photocatalyst by Sol-gel method to utilize visible light more efficiently for photocatalytic reactions. A noticeable shift of absorption edge to visible light region was obtained for the singly-doped namely V-TiO{sub 2}, N-TiO{sub 2} and codoped V-N-TiO{sub 2} samples in comparison with undoped TiO{sub 2}, with smallest band gap obtained with codoped-TiO{sub 2}. The photocatalytic activities for all TiO{sub 2} photocatalysts were tested by 4-chlorophenol (organic pollutant) degradation under visible light irradiation. It was found that codoped TiO{sub 2} exhibits the best photocatalytic activity, which could be attributed to the synergistic effect produced by V and N dopants.

  13. Synthesis and characterization of vanadium oxide aerogels. Technical report No. 2, 1 June 1994-31 May 1995

    SciTech Connect (OSTI)

    Chaput, F.; Dunn, B.; Fuqua, P.; Salloux, K.

    1995-07-14T23:59:59.000Z

    Vanadium pentoxide aerogels were synthesized by supercritical drying with CO2. The aerogels were prepared using a variety of sol compositions from the system VO(OC3H7)3/H2O/acetone. The materials were found to be of fairly low density (0.04g/cu cm to 0.lg/cu cm) with surface areas in the range of 300 to 400 meters squared/g. Chemical and structural studies indicate that the aerogels are hydrated oxides of composition V2O5 nH2O with n = 2.0 to 2.2 and possess a fibrous morphology. When partially dehydrated, the vanadate aerogels exhibit electron transport with conductivity and activation energy values comparable to those of aerogels. Electrochemical measurements demonstrate that lithium can be intercalated reversibly into the structure.

  14. Unveiling Surface Redox Charge Storage of Interacting Two-Dimensional Hetero-Nanosheets in Hierarchical Architectures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mahmood, Qasim; Bak, Seong-Min; Kim, Min G.; Yun, Sol; Yang, Xiao-Qing; Shin, Hyeon S.; Kim, Woo S.; Braun, Paul V.; Park, Ho S.

    2015-04-08T23:59:59.000Z

    Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to themore »interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane W–S lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of W–W bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.« less

  15. Received 11 Jan 2013 | Accepted 29 Apr 2013 | Published 13 Jun 2013 Cyclic electron flow is redox-controlled

    E-Print Network [OSTI]

    . Correspondence and requests for materials should be addressed to F.R. (email: Fabrice.Rappaport@ibpc.fr). NATURE Publishers Limited. All rights reserved. #12;T he injection of energy into the biosphere relies-containing stroma lamellae, thereby balancing the excitonic flux between the two photosystems10. In the unicellular

  16. Impact of membrane characteristics on the performance and cycling of the Br2-H2 redox flow cell

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)Hydrogen StorageITERITERBuildingNanoscale

  17. Some Lessons Learned from 20 Years in RedOx Flow Battery R&d | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideo »UsageSecretaryVideos Solid-State Lighting Videos On thisEnergy Moreof

  18. Influence of pH and Redox Conditions on Copper Leaching

    SciTech Connect (OSTI)

    Kavanaugh, Rathi; Al-Abed, Souhail R.; Purandare, Jaydeep; Allen, Derrick

    2004-03-31T23:59:59.000Z

    The Toxicity Characteristic Leaching Procedure (TCLP) is a regulatory leach test in the RCRA programs. It was developed to determine the leaching potential of landfilled waste in order to assess the hazards associated with the leachates. The test was developed to study concentration of hazardous materials in leachates, under a mismanagement scenario, when they are co-disposed with municipal waste. The test uses leaching of waste at either of two acidic pH values i.e., 2.8 and 4.93. While low pH leachant can extract many metals, some metals soluble at higher pH values are either underestimated or totally unaccounted for. The method also has limitations for application to different waste matrices. The procedure does not take into account the effect of redox conditions on leaching. Leaching studies are, therefore, being conducted to determine the effect of combinations of Eh and pH on the leaching potential of mineral and organic wastes. The goal of this study is to propose alternate methods applicable for a variety of waste matrices. The presentation will discuss the effects of combinations of pH and redox conditions on the leaching behavior of copper from a mineral processing waste.

  19. Redox Active Layer-by-Layer Structures containing MnO2 Nanoparticles

    SciTech Connect (OSTI)

    Bazito, Fernanda; O'Brien, Robert; Buttry, Daniel A.

    2005-02-01T23:59:59.000Z

    Nanoscale materials provide unique properties that will enable new technologies and enhance older ones. One area of intense activity in which nanoscale materials are being used is in the development of new functional materials for battery applications. This effort promises superior materials with properties that circumvent many of the problems associated with traditional battery materials. Previously we have worked on several approaches for using nanoscale materials for application as cathode materials in rechargeable Li batteries. Our recent work has focused on synthesizing MnO2 nanoparticles and using these in layer-by-layer (LbL) structures to probe the redox properties of the nanoparticles. We show that the aqueous colloidal nanoparticles produced by butanol reduction of tetramethylammonium permanganate can be trapped in thin films using a layer-by-layer deposition approach, and that these films are both redox active and exhibit kinetically facile electrochemical responses. We show cyclic voltammetry of MnO2 colloidal nanoparticles entrapped in a LbL thin film at an ITO electrode surface using poly(diallyldimethylammonium chloride) (PDDA). CV experiments demonstrate that Li+ insertion accompanies Mn(IV) reduction in LiClO4 supporting electrolytes, and that reduction is hindered in supporting electrolytes containing only tetrabutylammonium cations. We also show that electron propagation through multilayer films is facile, suggesting that electrons percolate through the films via electron exchange between nanoparticles.

  20. Molybdenum in Nuclear Waste Glasses -Incorporation and Redox state R.J. Short, R.J. Hand, N.C. Hyatt,

    E-Print Network [OSTI]

    Sheffield, University of

    Molybdenum in Nuclear Waste Glasses - Incorporation and Redox state R.J. Short, R.J. Hand, N form in simulated high level nuclear waste (HLW) glass melts have been studied. It was found less attention has been paid to the effects of redox on nuclear waste glasses. One particular element

  1. 1246 J. Am. Chem. SOC. 1995, 117, 1246-1257 RNA Aptamers That Bind Flavin and Nicotinamide Redox

    E-Print Network [OSTI]

    Heller, Eric

    that specifically bind riboflavin (Rb) and P-nicotinamide mononucleotide (NMN) have been isolated by in vitro to oxidized riboflavin (& = 1-5 pM). DNA versions of the consensus sequence also bind, but with weaker structural analog of riboflavin. In contrast to the lack of redox specificity of the riboflavin aptamers

  2. DOI: 10.1002/ejic.201000555 Flexible and Redox-Active Coordination Polymer: Control of the Network

    E-Print Network [OSTI]

    Paik Suh, Myunghyun

    *[a] Keywords: Coordination polymers / Flexible networks / Macrocyles / Palladium / Nickel The coordination[3a] as well as in the fourfold interpenetrating dia- mondoid network[11] by the reaction of organicFULL PAPER DOI: 10.1002/ejic.201000555 Flexible and Redox-Active Coordination Polymer: Control

  3. 5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) reduction in a mesophilic anaerobic digester: Measuring redox behavior,

    E-Print Network [OSTI]

    Pace, Norman

    this work suggest that CTC reduction in cell-free samples may impede accurate enzyme activity measurements: Measuring redox behavior, differentiating abiotic reduction, and comparing FISH response as an activity). Dehydrogenase activity assays and fluorescent in situ hybridization (FISH) were simultaneously carried out

  4. The development of a rod-coil redox polymer composed of biphenyl esters and poly (4-vinylpyridine)

    E-Print Network [OSTI]

    DeCormier, Amy Urbanowicz

    2001-01-01T23:59:59.000Z

    A rod-coil polymer was successfully synthesized to provide a backbone structure from which a redox polymer was produced. The rod was composed of biphenyl esters and the coil was composed of poly (4-vinylpyridine). The coil was produced by anionic...

  5. Mobilisation of arsenic from bauxite residue (red mud) affected soils: Effect of pH and redox conditions

    E-Print Network [OSTI]

    Burke, Ian

    ). Typically, it comprises residual iron oxides, quartz, sodium aluminosilicates, titanium dioxide, calciumMobilisation of arsenic from bauxite residue (red mud) affected soils: Effect of pH and redox elements, including arsenic. Aerobic and anaer- obic batch experiments were prepared using soils from near

  6. Discovery of agglutinated benthic foraminifera in Devonian black shales and their relevance for the redox state of ancient seas

    E-Print Network [OSTI]

    Polly, David

    Discovery of agglutinated benthic foraminifera in Devonian black shales and their relevance Received in revised form 4 October 2008 Accepted 31 October 2008 Keywords: Black shale Redox Devonian. The discovery that they occur widely in Late Devonian black shales has a bearing on the boundary conditions

  7. Ni(III)/(IV) Bis(dicarbollide) as a Fast, Noncorrosive Redox Shuttle for Dye-Sensitized Solar Cells

    E-Print Network [OSTI]

    Ni(III)/(IV) Bis(dicarbollide) as a Fast, Noncorrosive Redox Shuttle for Dye-Sensitized Solar Cells-marks@northwestern.edu; chadnano@northwestern.edu The favorable energetics of dye-sensitized solar cell (DSC) constituents have. Marks,*,, and Joseph T. Hupp*,,,§ Department of Chemistry, Argonne-Northwestern Solar Energy Research

  8. Solar Thermochemical Fuels Production: Solar Fuels via Partial Redox Cycles with Heat Recovery

    SciTech Connect (OSTI)

    None

    2011-12-19T23:59:59.000Z

    HEATS Project: The University of Minnesota is developing a solar thermochemical reactor that will efficiently produce fuel from sunlight, using solar energy to produce heat to break chemical bonds. The University of Minnesota is envisioning producing the fuel by using partial redox cycles and ceria-based reactive materials. The team will achieve unprecedented solar-to-fuel conversion efficiencies of more than 10% (where current state-of-the-art efficiency is 1%) by combined efforts and innovations in material development, and reactor design with effective heat recovery mechanisms and demonstration. This new technology will allow for the effective use of vast domestic solar resources to produce precursors to synthetic fuels that could replace gasoline.

  9. Redox Control For Hanford HLW Feeds VSL-12R2530-1, REV 0

    SciTech Connect (OSTI)

    Kruger, A. A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Matlack, Keith S. [The Catholic University of America, Washington, DC (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Kot, Wing K. [The Catholic University of America, Washington, DC (United States); Joseph, Innocent [The Catholic University of America, Washington, DC (United States)

    2012-12-13T23:59:59.000Z

    The principal objectives of this work were to investigate the effects of processing simulated Hanford HLW at the estimated maximum concentrations of nitrates and oxalates and to identify strategies to mitigate any processing issues resulting from high concentrations of nitrates and oxalates. This report provides results for a series of tests that were performed on the DM10 melter system with simulated C-106/AY-102 HLW. The tests employed simulated HLW feeds containing variable amounts of nitrates and waste organic compounds corresponding to maximum concentrations proj ected for Hanford HLW streams in order to determine their effects on glass production rate, processing characteristics, glass redox conditions, melt pool foaming, and the tendency to form secondary phases. Such melter tests provide information on key process factors such as feed processing behavior, dynamic effects during processing, processing rates, off-gas amounts and compositions, foaming control, etc., that cannot be reliably obtained from crucible melts.

  10. Micelle formation and surface activity of functional redox relays: viologens substituted by a long alkyl chain

    SciTech Connect (OSTI)

    Krieg, M.; Pileni, M.P.; Braun, A.M.; Gratzel, M.

    1981-09-01T23:59:59.000Z

    Viologens are receiving increasing attention from 2 major domains. First, photo- and electroreproductive processes are being developed which exploit the pronounced chromophore effect associated with the one-electron reduction of the viologens: the 2+ state is practically colorless, while the 1+ state has an intense color. However, the most prominent impact in viologen-related research arises from their use as mediators, sometimes referred to as electron relays, in the photionduced generation of hydrogen from water. Photobiologists had discovered earlier that methyl viologen in chloroplast suspensions is suited to act as a Hill reagent which can be coupled with hydrogenase to yield H/sub 2/ under illumination. More recently, in vitro systems have been developed in which synthetic dyes replace the chloroplasts as redox sensitizers. These have been shown to be remarkably effective in H/sub 2/ production. The surfactant and micellar properties of a series of potent candidates, i.e., long-chain-substituted viologens are investigated.

  11. Electrocatalytic hydrogenation using precious metal microparticles in redox-active polymer films

    SciTech Connect (OSTI)

    Coche, L.; Ehui, B.; Limosin, D.; Moutet, J.C. (Univ. Joseph Fourier, Grenoble (France))

    1990-11-09T23:59:59.000Z

    Glassy carbon felt electrodes have been modified by electrodeposition of poly(pyrrole-viologen) films (derived from N,N{prime}-dialkyl-4,4{prime}-bipyridinium salts), followed by electroprecipitation of precious metal (Pt, Pd, Rh, or Ru) microparticles. The resulting electrodes have been proved to be active for the electrocatalytic hydrogenation of conjugated enones (2-cyclohexen-1-one, cryptone, carvone, isophorone), styrene, and benzonitrile in aqueous media (pH 1). Despite low loadings of metal catalysts, high electric and products yields and a long term stability of these cathodes have been observed. The influence of the metal loading and the polymer structure on the catalytic efficiency as well as the selectivity obtained according to the metal catalyst used have been studied. Comparison with results previously reported for other catalytic cathodes like Pt/Pt, Pd/C, or Raney nickel electrodes proves the high efficiency of these metal microparticles within redox polymer film based electrodes.

  12. The complementary redox properties of viologens and pyromellitimides: A new class of organic conductors

    SciTech Connect (OSTI)

    Buchwalter, S.L.; Iyengar, R.; Viehbeck, A.; O'Toole, T.R. (Thomas J. Watson Research Center, Yorktown Heights, NY (USA))

    1991-01-02T23:59:59.000Z

    Organic charge-transfer (CT) salts have been of interest for some years, especially since the discovery of the metallic conductivity of the TTF-TCNQ salt. The authors have begun an investigation of the charge-transfer chemistry of viologens and pyromellitimides, based on their complementary redox properties, with the intention of proceeding from intermolecular examples to intramolecular CT salts and finally to examples in which the viologens and pyromellitimides are incorporated in a polymer. They report progress in the first two stages of this investigation, including isolation of a new, highly conductive intermolecular CT salt and electrochemical characterization of a covalently linked viologen/pyromellitimide. These studies point to an interesting new class of organic solid-state materials.

  13. Investigation of photoelectrode redox polymer junctions. Technical report, 16 November-15 January 1984

    SciTech Connect (OSTI)

    Cook, R.L.; Sammells, A.F.

    1985-01-15T23:59:59.000Z

    The n-CdS flatband potential in the solid-state cell n-CdS/Nafion 117 + redox species/Au was shifted progressively in a cathode directed upon the introduction of FeCp2, FeCp2 + Ru(bpy)3(2+) into the SPE. This cathodic shift was consistent with that for the oxidation potentials seen for Ru(bpy)3(2+) (E1/2 = 1.25V vs SCE) and FeCp2 (0.285V vs SCE) in acetonitrile. Such perturbations of semiconductor properties can be expected to form the basis of a detector technology when the semiconductor/SPE junction is exposed to selected chemical species.

  14. GEOC R Lee Penn Sunday, March 25, 2012 12 -Biogeochemical transformation of Fe-and Mn-along a redox gradient: Implications for carbon sequestration

    E-Print Network [OSTI]

    Sparks, Donald L.

    a redox gradient: Implications for carbon sequestration within the Christina River Basin Critical Zone States Organic carbon (C)-mineral complexation mechanism is crucial in C sequestration. It is a function

  15. The Redox Domain of the Yap1p Transcription Factor Contains Two Disulfide Matthew J. Wood, Erika C. Andrade, and Gisela Storz*

    E-Print Network [OSTI]

    Storz, Gisela

    separate cysteine-containing peptides of Yap1p. These peptides are separated by 250 amino acids to only serve as antioxidants, such as Cys-2 Prxs and Gpx3p, now appear to be redox regulated and play

  16. A novel redox-based switch: LMW-PTP oxidation enhances Grb2 binding and leads to ERK activation

    SciTech Connect (OSTI)

    Giannoni, Elisa [Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence (Italy); Raugei, Giovanni [Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence (Italy); Center of Excellence for Scientific Research DENOTHE, Viale Morgagni 44, 50134 Florence (Italy); Chiarugi, Paola [Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence (Italy) and Center of Excellence for Scientific Research DENOTHE, Viale Morgagni 44, 50134 Florence (Italy)]. E-mail: paola.chiarugi@unifi.it; Ramponi, Giampietro [Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence (Italy); Center of Excellence for Scientific Research DENOTHE, Viale Morgagni 44, 50134 Florence (Italy)

    2006-09-22T23:59:59.000Z

    Low molecular weight-PTP has been reported as a redox-sensitive protein during both platelet-derived growth factor and integrin signalling. In response to oxidation the phosphatase undergoes a reversible inactivation, which in turn leads to the increase in tyrosine phosphorylation of its substrates and the properly executed anchorage-dependent proliferation program. Here, we report that an exogenous oxidative stress enhances LMW-PTP tyrosine phosphorylation, through oxidation/inactivation of the enzyme, thus preventing its auto-dephosphorylation activity. In particular, we observed a selective hyper-phosphorylation of Tyr132, that acts as a docking site for the adaptor protein Grb2. The redox-dependent enhancement of Grb2 recruitment to LMW-PTP ultimately leads to an improvement of ERK activation, likely triggering a prosurvival signal against the oxidant environment.

  17. Low volume flow meter

    DOE Patents [OSTI]

    Meixler, Lewis D. (East Windsor, NJ)

    1993-01-01T23:59:59.000Z

    The low flow monitor provides a means for determining if a fluid flow meets a minimum threshold level of flow. The low flow monitor operates with a minimum of intrusion by the flow detection device into the flow. The electrical portion of the monitor is externally located with respect to the fluid stream which allows for repairs to the monitor without disrupting the flow. The electronics provide for the adjustment of the threshold level to meet the required conditions. The apparatus can be modified to provide an upper limit to the flow monitor by providing for a parallel electronic circuit which provides for a bracketing of the desired flow rate.

  18. Ichno-sedimentological record of short-term climate-controlled redox events and cycles in organic-rich strata

    SciTech Connect (OSTI)

    Savrda, C.E. (Auburn Univ., AL (USA)); Bottjher, D.J. (Univ. of Southern California, Los Angeles (USA)); Ozalas, K. (Auburn Univ., AL (USA))

    1990-05-01T23:59:59.000Z

    Reduced rates of biochemical degradation of organic matter in oxygen-depleted marine settings generally result in the accumulation of laminated strata with high hydrocarbon source potential. Periods of improved oxygenation, during which the quantity and quality of organic matter are effectively reduced, are reflected by interbedded bioturbated intervals. Such benthic redox excursions may reflect variable paleooceanographic responses to climatic events or cycles. The potential role of climate in the short-term modulation of source rock potential is exemplified by bioturbated intervals within three predominantly laminated organic-rich units. The Jurassic Posidonia Shale (Germany) contains bioturbated beds whose ichnologic characteristics reflect a spectrum from short, low-magnitude redox events to longer episodes of greater magnitude. The character and distribution of these event beds appear to be controlled by sea level mediated variations in the frequency and intensity of storm-induced basin turnover. Bioturbated beds of the Upper Cretaceous Niobrara Formation (Colorado) are characterized by four oxygen-related ichnocoenoses, the distribution of which reflects cyclic variations in redox conditions. Relationships between paleooxygenation and organic-carbon and carbonate contents, and estimated cycle periodicities, suggest that redox variations were controlled by wet-dry climatic cycles modulated by the Milankovitch cycle of axial precession. Bioturbated beds within slope and basinal facies of the Miocene Monterey Formation (California) are variable in character, reflecting differences in duration and magnitude of associated oxygenation episodes, and may be in response to short-term variations in wind-stress-induced upwelling and/or ice-volume-controlled eustatic sea level changes.

  19. The strong reactions of Lewis-base noble-metals with vanadium and other acidic transition metals

    SciTech Connect (OSTI)

    Ebbinghaus, B.B.

    1991-05-01T23:59:59.000Z

    The noble metals often thought of as unreactive solids,react strongly with nearly 40% of the elements in the periodictable: group IIIB-VB transition metals, lanthanides, theactinides, and group IIIA-IVA non-transition metals. These strong reactions arise from increased bonding/electron transfer fromnonbonding electrons d electron pairs on the noble metal tovacant orbitals on V, etc. This effect is a generalized Lewis acid-base interaction. The partial Gibbs energy of V in the noblemetals has been measured as a function of concentration at a temperature near 1000C. Thermodynamics of the intermetallics are determined by ternary oxide equilibria, ternary carbide equilibria, and the high-temperature galvanic cell technique. These experimental methods use equilibrated solid composite mixtures in which grains of V oxides or of V carbides are interspersed with grains of V-NM(noble-metal) alloys. In equilibrium the activity of V in the oxide or the carbide equals the activity in the alloy. Consequently, the thermodynamics available in the literature for the V oxides and V carbides are reviewed. Test runs on the galvanic cell were attempted. The V oxide electrode reacts with CaF[sub 2], ThO[sub 2], YDT(0.85ThO[sub 2]-0.15YO[sub 1.5]), and LDT(0.85ThO[sub 2]- 0.15LaO[sub 1.5]) to interfere with the measured data observed toward the beginning of a galvanic cell experiment are the most accurate. The interaction of vanadium at infinite dilution in the noble-metals was determined.

  20. The strong reactions of Lewis-base noble-metals with vanadium and other acidic transition metals

    SciTech Connect (OSTI)

    Ebbinghaus, B.B.

    1991-05-01T23:59:59.000Z

    The noble metals often thought of as unreactive solids,react strongly with nearly 40% of the elements in the periodictable: group IIIB-VB transition metals, lanthanides, theactinides, and group IIIA-IVA non-transition metals. These strong reactions arise from increased bonding/electron transfer fromnonbonding electrons d electron pairs on the noble metal tovacant orbitals on V, etc. This effect is a generalized Lewis acid-base interaction. The partial Gibbs energy of V in the noblemetals has been measured as a function of concentration at a temperature near 1000C. Thermodynamics of the intermetallics are determined by ternary oxide equilibria, ternary carbide equilibria, and the high-temperature galvanic cell technique. These experimental methods use equilibrated solid composite mixtures in which grains of V oxides or of V carbides are interspersed with grains of V-NM(noble-metal) alloys. In equilibrium the activity of V in the oxide or the carbide equals the activity in the alloy. Consequently, the thermodynamics available in the literature for the V oxides and V carbides are reviewed. Test runs on the galvanic cell were attempted. The V oxide electrode reacts with CaF{sub 2}, ThO{sub 2}, YDT(0.85ThO{sub 2}-0.15YO{sub 1.5}), and LDT(0.85ThO{sub 2}- 0.15LaO{sub 1.5}) to interfere with the measured data observed toward the beginning of a galvanic cell experiment are the most accurate. The interaction of vanadium at infinite dilution in the noble-metals was determined.

  1. Redox-Dependent Solubility of Technetium in Low Activity Waste Glass

    SciTech Connect (OSTI)

    Soderquist, Chuck Z.; Schweiger, Michael J.; Kim, Dong-Sang; Lukens, Wayne W.; Mccloy, John S.

    2014-03-01T23:59:59.000Z

    The solubility of technetium was measured in a Hanford low activity waste glass simulant. The simulant glass was melted, quenched and pulverized to make a stock of powdered glass. A series of glass samples were prepared using the powdered glass and varying amounts of solid potassium pertechnetate. Samples were melted at 1000°C in sealed fused quartz ampoules. After cooling, the bulk glass and the salt phase above the glass (when present) were sampled for physical and chemical characterization. Technetium was found in the bulk glass up to 2000 ppm (using the glass as prepared) and 3000 ppm (using slightly reducing conditions). The chemical form of technetium obtained by x-ray absorption near edge spectroscopy can be mainly assigned to isolated Tc(IV), with a minority of Tc(VII) in some glasses and TcO2 in two glasses. The concentration and speciation of technetium depends on glass redox and amount of technetium added. Solid crystals of pertechnetate salts were found in the salt cake layer that formed at the top of some glasses during the melt.

  2. JUPITER-II Molten Salt Flibe Research: An Update On Tritium, Mobilization and Redox Chemistry Experiments

    SciTech Connect (OSTI)

    D.A. Petti; D. A. Petti; G. R. Smolik; Michael F. Simpson; John P. Sharpe; R. A. Anderl; S. Fukada; Y. Hatano; Masanori Hara; Y. Oya; T. Terai; D.-K. Sze; S. Tanaka

    2005-05-01T23:59:59.000Z

    The second Japan/US Program on Irradiation Tests for Fusion Research (JUPITER-II) began on April 1, 2001. Part of the collaborative research centers on studies of the molten salt 2LiF2–BeF2 (also known as Flibe) for fusion applications. Flibe has been proposed as a self-cooled breeder in both magnetic and inertial fusion power plant designs over the last 25 years. The key feasibility issues associated with the use of Flibe are the corrosion of structural material by the molten salt, tritium behavior and control in the molten salt blanket system, and safe handling practices and releases from Flibe during an accidental spill. These issues are all being addressed under the JUPITER-II program at the Idaho National Laboratory in the Safety and Tritium Applied Research (STAR) facility. In this paper, we review the program to date in the area of tritium/deuterium behavior, Flibe mobilization under accident conditions and testing of Be as a redox agent to control corrosion. Future activities planned through the end of the collaboration are also presented.

  3. Chemiluminescence Excitation in the Redox Reactions of MetalCarbonyls and Their Derivatives with Xenon Difluoride

    SciTech Connect (OSTI)

    Bulgakov, R.G.; Kuleshov, S.P.; Tolstikov, G.A; Yakoulev, V.N.

    1985-11-01T23:59:59.000Z

    The authors use gas-liquid chromatography, volumetry, elemental analysis, and UV, visible, and IR absorption spectroscopy to study the oxidation of XeF/sub 2/ by carbonyls of group VI-VIII metals Mo(CO)/sub 6/, (C/sub 6/H/sub 5/CH/sub 3/) Mo(CO)/sub 3/, W(CO)/sub 6/, Mn/sub 2/(CO)/sub 10/, C/sub 5/H/sub 5/Mn(CO)/sub 3/, Fe(CO)/sub 5/, Fe/sub 2/(CO)/sub 9/, and (acac) Rh(CO)/sub 2/. The reactions are accompanied by change in solution color, the release of gaseous Xe and CO, and the formation of fluoro derivatives of metal carbonyls and metal fluorides. Chemiluminescence is excited in the overall process of the consecutive redox replacement of CO groups in the metal carbonyl by F. The only case of the absence of chemiluminescence in the case of the oxidation of Mn/sub 2/(CO)/sub 10/ is related to the existence of an Mn-Mn bond in this metal carbonyl. Mn/sub 2/(CO)/sub 10/ also efficiently quenches the background chemiluminescence due to the reaction of XeF/sub 2/ with CH/sub 2/Cl/sub 2/ and toluene.

  4. Transitions from near-surface to interior redox upon lithiation in conversion electrode materials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, Kai; Xin, Huolin L.; Zhao, Kejie; Yu, Xiqian; Norlund, Dennis; Weng, Tsu-Chien; Li, Jing; Jiang, Yi; Cadigan, Christopher A.; Richards, Ryan M.; et al

    2015-02-11T23:59:59.000Z

    Nanoparticle electrodes in lithium-ion batteries have both near-surface and interior contributions to their redox capacity, each with distinct rate capabilities. Using combined electron microscopy, synchrotron X-ray methods and ab initio calculations, we have investigated the lithiation pathways that occur in NiO electrodes. We find that the near-surface electroactive (Ni²??Ni?) sites saturated very quickly, and then encounter unexpected difficulty in propagating the phase transition into the electrode (referred to as a “shrinking-core” mode). However, the interior capacity for Ni²??Ni? can be accessed efficiently following the nucleation of lithiation “fingers” which propagate into the sample bulk, but only after a certain incubationmore »time. Our microstructural observations of the transition from a slow shrinking-core mode to a faster lithiation finger mode corroborate with synchrotron characterization of large-format batteries, and can be rationalized by stress effects on transport at high-rate discharge. The finite incubation time of the lithiation fingers sets the intrinsic limitation for the rate capability (and thus the power) of NiO for electrochemical energy storage devices. The present work unravels the link between the nanoscale reaction pathways and the C-rate-dependent capacity loss, and provides guidance for the further design of battery materials that favors high C-rate charging.« less

  5. Stable-isotope probe of nano-scale mineral-fluid redox interactions

    SciTech Connect (OSTI)

    Kavner, Abby

    2014-11-26T23:59:59.000Z

    The project examined how stable isotopes fractionate at an aqueous/solid interface during electrochemical reduction reactions. Measurements in a wide variety of metal deposition systems including Fe, Zn, Li, Mo, and Cu, have led to observations of large isotope fractionations which strongly vary as a function of rate and temperature. For the Fe, Zn, and Li systems, our electrochemical deposition methods provide the largest single-pass fractionation factors that are observed for these systems. Based on these and other experiments and theory showing and predicting significant and rate-dependent fractionations of isotopes at reacting interfaces, we have developed a simple statistical mechanics framework that predicts the kinetic isotope effect accompanying phase transformations in condensed systems. In addition, we have begun to extend our studies of mineral-fluid redox interactions to high pressures and temperatures in the diamond anvil cell. We performed a series of experiments to determine solubilities of Cu and Ni at elevated pressure and temperature conditions relevant to ore-formation.

  6. Transitions from near-surface to interior redox upon lithiation in conversion electrode materials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, Kai [Brookhaven National Lab. (BNL), Upton, NY (United States); Xin, Huolin L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhao, Kejie [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Yu, Xiqian [Brookhaven National Lab. (BNL), Upton, NY (United States); Norlund, Dennis [SLAC National Accelerator Lab., Menlo Park, CA (United States); Weng, Tsu-Chien [SLAC National Accelerator Lab., Menlo Park, CA (United States); Li, Jing [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Jiang, Yi [Cornell Univ., Ithaca, NY (United States); Cadigan, Christopher A. [Colorado School of Mines, Golden, CO (United States); Richards, Ryan M. [Colorado School of Mines, Golden, CO (United States); Doeff, Marca M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yang, Xiao-Qing [Brookhaven National Lab. (BNL), Upton, NY (United States); Stach, Eric A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Li, Ju [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Lin, Feng [Colorado School of Mines, Golden, CO (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Su, Dong [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States)

    2015-02-11T23:59:59.000Z

    Nanoparticle electrodes in lithium-ion batteries have both near-surface and interior contributions to their redox capacity, each with distinct rate capabilities. Using combined electron microscopy, synchrotron X-ray methods and ab initio calculations, we have investigated the lithiation pathways that occur in NiO electrodes. We find that the near-surface electroactive (Ni²??Ni?) sites saturated very quickly, and then encounter unexpected difficulty in propagating the phase transition into the electrode (referred to as a “shrinking-core” mode). However, the interior capacity for Ni²??Ni? can be accessed efficiently following the nucleation of lithiation “fingers” which propagate into the sample bulk, but only after a certain incubation time. Our microstructural observations of the transition from a slow shrinking-core mode to a faster lithiation finger mode corroborate with synchrotron characterization of large-format batteries, and can be rationalized by stress effects on transport at high-rate discharge. The finite incubation time of the lithiation fingers sets the intrinsic limitation for the rate capability (and thus the power) of NiO for electrochemical energy storage devices. The present work unravels the link between the nanoscale reaction pathways and the C-rate-dependent capacity loss, and provides guidance for the further design of battery materials that favors high C-rate charging.

  7. Macroscopic Properties of Restacked, Redox-Liquid Exfoliated Graphite and Graphite Mimics Produced in Bulk Quantities

    SciTech Connect (OSTI)

    Srivastava, Vikram K [ORNL; Quinlan, Ronald [ORNL; Agapov, Alexander L [ORNL; Dunlap, John R [ORNL; Nelson, Kimberly M [ORNL; Duranty, Edward R [ORNL; Sokolov, Alexei P [ORNL; Bhat, Gajanan [ORNL; Mays, Jimmy [ORNL

    2014-01-01T23:59:59.000Z

    The excellent properties exhibited by monolayer graphene have spurred the development of exfoliation techniques using bulk graphite to produce large quantities of pristine monolayer sheets. Development of simple chemistry to exfoliate and intercalate graphite and graphite mimics in large quantities is required for numerous applications. To determine the macroscopic behavior of restacked, exfoliated bulk materials, a systematic approach is presented using a simple, redox-liquid sonication process along to obtain large quantities of 2D and 3D hexagonally layered graphite, molybdenum disulfi de, and boron nitride, which are subsequently characterized to observe chemical and structural changes. For MoS 2 sonicated with the antioxidant sodium bisulfi te, results from Raman spectroscopy, X-ray diffraction, and electron microscopy indicate the presence of distorted phases from different polymorphs, and apparent nanotube structures in the bulk, restacked powder. Furthermore, using thermograviemtric analysis, the antioxidant enhances the resistance to oxidative degradation of MoS 2 , upon thermal treatment up to 900 C. The addition of the ionic antioxidant decreased dispersion stability in non-polar solvent, suggesting decreased compatibility with non-polar systems. Using simple chemical methods, the ability to generate tailored multidimensional layered materials with unique macroscopic properties is critical for numerous applications, including electrical devices, reinforced polymer composites, lithium ion capacitors, and chemical sensing.

  8. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  9. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01T23:59:59.000Z

    Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

  10. ROLE OF MANGANESE REDUCTION/OXIDATION (REDOX) ON FOAMING AND MELT RATE IN HIGH LEVEL WASTE (HLW) MELTERS (U)

    SciTech Connect (OSTI)

    Jantzen, C; Michael Stone, M

    2007-03-30T23:59:59.000Z

    High-level nuclear waste is being immobilized at the Savannah River Site (SRS) by vitrification into borosilicate glass at the Defense Waste Processing Facility (DWPF). Control of the Reduction/Oxidation (REDOX) equilibrium in the DWPF melter is critical for processing high level liquid wastes. Foaming, cold cap roll-overs, and off-gas surges all have an impact on pouring and melt rate during processing of high-level waste (HLW) glass. All of these phenomena can impact waste throughput and attainment in Joule heated melters such as the DWPF. These phenomena are caused by gas-glass disequilibrium when components in the melter feeds convert to glass and liberate gases such as H{sub 2}O vapor (steam), CO{sub 2}, O{sub 2}, H{sub 2}, NO{sub x}, and/or N{sub 2}. During the feed-to-glass conversion in the DWPF melter, multiple types of reactions occur in the cold cap and in the melt pool that release gaseous products. The various gaseous products can cause foaming at the melt pool surface. Foaming should be avoided as much as possible because an insulative layer of foam on the melt surface retards heat transfer to the cold cap and results in low melt rates. Uncontrolled foaming can also result in a blockage of critical melter or melter off-gas components. Foaming can also increase the potential for melter pressure surges, which would then make it difficult to maintain a constant pressure differential between the DWPF melter and the pour spout. Pressure surges can cause erratic pour streams and possible pluggage of the bellows as well. For these reasons, the DWPF uses a REDOX strategy and controls the melt REDOX between 0.09 {le} Fe{sup 2+}/{summation}Fe {le} 0.33. Controlling the DWPF melter at an equilibrium of Fe{sup +2}/{summation}Fe {le} 0.33 prevents metallic and sulfide rich species from forming nodules that can accumulate on the floor of the melter. Control of foaming, due to deoxygenation of manganic species, is achieved by converting oxidized MnO{sub 2} or Mn{sub 2}O{sub 3} species to MnO during melter preprocessing. At the lower redox limit of Fe{sup +2}/{summation}Fe {approx} 0.09 about 99% of the Mn{sup +4}/Mn{sup +3} is converted to Mn{sup +2}. Therefore, the lower REDOX limits eliminates melter foaming from deoxygenation.

  11. Electron Transfer Reactivity Patterns at Chemically Modified Electrodes: Fundamentals and Application to the Optimization of Redox Recycling Amplification Systems

    SciTech Connect (OSTI)

    Adam Johan Bergren

    2006-05-01T23:59:59.000Z

    Electroanalytical chemistry is often utilized in chemical analysis and Fundamental studies. Important advances have been made in these areas since the advent of chemically modified electrodes: the coating of an electrode with a chemical film in order to impart desirable, and ideally, predictable properties. These procedures enable the exploitation of unique reactivity patterns. This dissertation presents studies that investigate novel reaction mechanisms at self-assembled monolayers on gold. In particular, a unique electrochemical current amplification scheme is detailed that relies on a selective electrode to enable a reactivity pattern that results in regeneration of the analyte (redox recycling). This regenerating reaction can occur up to 250 times for each analyte molecule, leading to a notable enhancement in the observed current. The requirements of electrode selectivity and the resulting amplification and detection limit improvements are described with respect to the heterogeneous and homogeneous electron transfer rates that characterize the system. These studies revealed that the heterogeneous electrolysis of the analyte should ideally be electrochemically reversible, while that for the regenerating agent should be held to a low level. Moreover, the homogeneous reaction that recycles the analyte should occur at a rapid rate. The physical selectivity mechanism is also detailed with respect to the properties of the electrode and redox probes utilized. It is shown that partitioning of the analyte into/onto the adlayer leads to the extraordinary selectivity of the alkanethiolate monolayer modified electrode. Collectively, these studies enable a thorough understanding of the complex electrode mechanism required for successful redox recycling amplification systems, Finally, in a separate (but related) study, the effect of the akyl chain length on the heterogeneous electron transfer behavior of solution-based redox probes is reported, where an odd-even oscillation (with respect to the number of methylene units in the alkyl chain) was observed. Characterization of the adlayers by infrared reflection spectroscopy, ellipsometry, and wetting revealed odd-even effects in the orientation of the terminal methyl group and hydrophobic character of the adlayers. Using these structural characterizations as a basis, several possible mechanisms that can account for the odd-even effect in the heterogeneous electron transfer rates of solution-based redox couples are discussed.

  12. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15T23:59:59.000Z

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

  13. Synthesis of Nanostructured Carbides of Titanium and Vanadium from Metal Oxides and Ferroalloys Through High-energy Mechanical Milling and Heat Treatment

    SciTech Connect (OSTI)

    Basu, P.; Jian, P. F.; Seong, K. Y.; Seng, G. S.; Hussain, Z.; Aziz, A. [School of Materials and Minerals Resources Engineering, Universiti Sains Malaysia (USM), Engineering Campus, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Masrom, A. K. [Advanced Materials Research Centre (AMREC), SIRIM Bhd, Kulim Hi-Tech Park, Kulim 09000 (Malaysia)

    2010-03-11T23:59:59.000Z

    Carbides of Ti and V have been synthesized directly from their oxides and ferroalloys through mechanical milling and heat treatment. The powder mixtures are milled in a planetary ball mill from 15-80 hours and subsequently heat treated at 1000-1300 deg. C for TiO{sub 2}-C mixtures, at 500-550 deg. C for V{sub 2}O{sub 5}-C mixtures and at 600-1000 deg. C for (Fe-V)-C mixtures. The milled and heat treated powders are characterized by SEM, EDAX, XRD, and BET techniques. Nanostructured TiC has been successfully synthesized under suitable processing conditions. However, carbides of vanadium is unidentified even though possibilities of V{sub 2}O{sub 5}-C reaction are indicated with an extent of induced amorphism in the powder mixture. Density, specific surface area and particle size of the milled and heat treated mixtures are correlated with heat treatment temperatures. Similar attempts are also made to synthesize vanadium carbides from industrial grade Fe-V.

  14. JOURNAL DE PHYSIQUE CoZZoque C8, suppZ6ment au n08, Tome 41, aoGt 1980, page C8-163 STUDY OF LIQUID NICKEL-VANADIUM ALLOYS BY NEUTRON DIFFRACTION AND MODEL SIMULATION

    E-Print Network [OSTI]

    Boyer, Edmond

    , 28 i s the scattering angle, X the neutron wave- length, Q = 4n the modulus of the scattering vector NICKEL-VANADIUM ALLOYS BY NEUTRON DIFFRACTION AND MODEL SIMULATION J.L. Lemarchand, J. Bletry and P with model c a l c u l a t i o ~can lead to a quantitative interpreta- tion. In this paper, neutron

  15. An analysis of a back-fed porous electrode for the bromine/bromide redox reaction

    E-Print Network [OSTI]

    Van Zee, John William

    1982-01-01T23:59:59.000Z

    that of the front-fed electrode (compare Figs. 1 and 2) This reduction in electrode gap could decrease the cell's specific resistance by more than 25% in Zn/Hrl batteries if a relatively nonconducting complexing agent (3) is present in the electrolyte. (The... of the back-fed electrode Previous Steady State Analyses Previous steady state analyses of porous electrodes have been presented for diffusion electrodes and for electrodes with electrolyte flowing through them. Two classes of flow-through electrodes...

  16. Experimental and theoretical studies of reactions of neutral vanadium and tantalum oxide clusters with NO and NH3

    E-Print Network [OSTI]

    Rocca, Jorge J.

    molecules on the respective clusters. A gas mixture of NO:NH3 9:1 is also added into the fast flow reactor oxide clusters with NO, NH3, and an NO/NH3 mixture in a fast flow reactor are investigated by time, a complete elucidation of the reaction mechanism has not been achieved, and very few, if any, gas phase

  17. Freshwater Flow Charts - 1995

    SciTech Connect (OSTI)

    Kaiper, G V

    2003-11-21T23:59:59.000Z

    This report covers the following: (1) Explanation of Charts Showing Freshwater Flow in 1995; (2) Estimated U.S. Freshwater Flow in 1995 (chart); (3) Estimated California Freshwater Flow in 1995 (chart); (4) Estimated New Mexico Freshwater Flow in 1995 (chart); and (5) Web locations and credits.

  18. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1990-01-01T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  19. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1999-02-02T23:59:59.000Z

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  20. West Valley glass product qualification durability studies, FY 1987--1988: Effects of composition, redox state, thermal history, and groundwater

    SciTech Connect (OSTI)

    Reimus, M.A.H.; Piepel, G.F.; Mellinger, G.B.; Bunnell, L.R.

    1988-11-01T23:59:59.000Z

    The product qualification subtask of the West Valley Support Task (WVST) at Pacific Northwest Laboratory (PNL) provides support for the waste form qualification efforts at West Valley Nuclear Services Co. Testing is being conducted to determine waste form chemical durability in support of these efforts. The effects of composition, ferrous/ferric ratio (redox state), thermal history, and groundwater are being investigated. Glasses were tested using modified Materials Characterization Center (MCC) -3 and MCC-1 test methods. Results obtained in fiscal years (FY) 1987 and 1988 are presented here. 13 refs., 27 figs., 36 tabs.

  1. Structural, Spectroscopic, And Theoretical Elucidation of a Redox-Active Pincer-Type Ancillary Applied in Catalysis

    SciTech Connect (OSTI)

    Adhikari, D.; Mossin, S.; Basuli, F.; Huffman, J.C.; Szilagyi, R.K.; Meyer, K.; Mindiola, D.J.

    2009-05-11T23:59:59.000Z

    Pincer-type ligands are believed to be very robust scaffolds that can support multifarious functionalities as well as highly reactive metal motifs applied in organometallic chemistry, especially in the realm of catalysis. In this paper, we describe the redox and, therefore, noninnocent behavior of a PNP (PNP{sup -} = N[2-P(CHMe{sub 2}){sub 2}-4-methylphenyl]{sub 2}) pincer ancillary bound to nickel. A combination of structural, spectroscopic, and theoretical techniques suggests that this type of framework can house an electron hole when coordinated to Ni(II).

  2. Doped Yttrium Chromite-Ceria Composite as a Redox-Stable and Sulfur-Tolerant Anode for Solid Oxide Fuel Cells

    SciTech Connect (OSTI)

    Yoon, Kyung J.; Coyle, Christopher A.; Marina, Olga A.

    2011-12-11T23:59:59.000Z

    A Ca- and Co-doped yttrium chromite (YCCC) - samaria-doped ceria (SDC) composite was studied in relation to a potential use as a solid oxide fuel cell (SOFC) anode material. Tests performed using the yttria-stabilized zirconia (YSZ) electrolyte-supported cells revealed that the electrocatalytic activity of the YCCC-SDC anode towards hydrogen oxidation at 800 C was comparable to that of the Ni-YSZ anode. In addition, the YCCC-SDC anode exhibited superior sulfur tolerant characteristics showing less than 10% increase in a polarization resistance, fully reversible, upon exposure to 20 ppm H2S at 800 C. No performance degradation was observed during multiple reduction-oxidation (redox) cycles when the anode was intentionally exposed to the air environment followed by the reduction in hydrogen. The redox tolerance of the YCCC-SDC anode was attributed to the dimensional and chemical stability of the YCCC exhibiting minimal isothermal chemical expansion upon redox cycling.

  3. Pore-Scale Characterization of Biogeochemical Controls on Iron and Uranium Speciation under Flow Conditions

    SciTech Connect (OSTI)

    Pearce, Carolyn I.; Wilkins, Michael J.; Zhang, Changyong; Heald, Steve M.; Fredrickson, Jim K.; Zachara, John M.

    2012-09-17T23:59:59.000Z

    Etched silicon microfluidic pore network models (micromodels) with controlled chemical and redox gradients, mineralogy, and microbiology under continuous flow conditions are used for the incremental development of complex microenvironments that simulate subsurface conditions. We demonstrate the colonization of micromodel pore spaces by an anaerobic Fe(III)-reducing bacterial species (Geobacter sulfurreducens) and the enzymatic reduction of a bioavailable Fe(III) phase within this environment. Using both X-ray Microprobe and X-ray Absorption Spectroscopy, we investigate the combined effects of the precipitated Fe(III) phases and the microbial population on uranium biogeochemistry under flow conditions. Precipitated Fe(III) phases within the micromodel were most effectively reduced in the presence of an electron shuttle (AQDS), and Fe(II) ions adsorbed onto the precipitated mineral surface without inducing any structural change. In the absence of Fe(III), U(VI) was effectively reduced by the microbial population to insoluble U(IV), which was precipitated in discrete regions associated with biomass. In the presence of Fe(III) phases, however, both U(IV) and U(VI) could be detected associated with biomass, suggesting re-oxidation of U(IV) by localized Fe(III) phases. These results demonstrate the importance of the spatial localization of biomass and redox active metals, and illustrate the key effects of pore-scale processes on contaminant fate and reactive transport.

  4. Liquid-phase oxidation of anthracene by hydrogen peroxide in the presence of vanadium oxide bronzes Cu{sub x}V{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    Men`shikov, S.Yu.; Vurasko, A.V.; Petrov, L.A.; Volkov, V.L.; Novoselova, A.A. [Inst. of Chemistry, Sverdlovsk (Russian Federation)

    1992-12-31T23:59:59.000Z

    Vanadium oxide bronzes of the general formula Cu{sub x}V{sub 2}O{sub 5}, where 0

  5. Coupled modeling of groundwater flow solute transport, chemical reactions and microbial processes in the 'SP' island

    SciTech Connect (OSTI)

    Samper, Javier; Molinero, Jorg; Changbing, Yang; Zhang, Guoxiang

    2003-12-01T23:59:59.000Z

    The Redox Zone Experiment was carried out at the Aespoe HRL in order to study the redox behavior and the hydrochemistry of an isolated vertical fracture zone disturbed by the excavation of an access tunnel. Overall results and interpretation of the Redox Zone Project were reported by /Banwart et al, 1995/. Later, /Banwart et al, 1999/ presented a summary of the hydrochemistry of the Redox Zone Experiment. Coupled groundwater flow and reactive transport models of this experiment were carried out by /Molinero, 2000/ who proposed a revised conceptual model for the hydrogeology of the Redox Zone Experiment which could explain simultaneously measured drawdown and salinity data. The numerical model was found useful to understand the natural system. Several conclusions were drawn about the redox conditions of recharge waters, cation exchange capacity of the fracture zone and the role of mineral phases such as pyrite, calcite, hematite and goethite. This model could reproduce the measured trends of dissolved species, except for bicarbonate and sulfate which are affected by microbially-mediated processes. In order to explore the role of microbial processes, a coupled numerical model has been constructed which accounts for water flow, reactive transport and microbial processes. The results of this model is presented in this report. This model accounts for groundwater flow and reactive transport in a manner similar to that of /Molinero, 2000/ and extends the preliminary microbial model of /Zhang, 2001/ by accounting for microbially-driven organic matter fermentation and organic matter oxidation. This updated microbial model considers simultaneously the fermentation of particulate organic matter by yeast and the oxidation of dissolved organic matter, a product of fermentation. Dissolved organic matter is produced by yeast and serves also as a substrate for iron-reducing bacteria. Model results reproduce the observed increase in bicarbonate and sulfate concentration, thus adding additional evidence for the possibility of organic matter oxidation as the main source of bicarbonate. Model results indicate that pH and Eh are relatively stable. The dissolution-precipitation trends of hematite, pyrite and calcite also coincide with those indicated by the conceptual model. A thorough sensitivity analysis has been performed for the most relevant microbial parameters as well as for initial and boundary POC and DOC concentrations. The results of such analysis indicate that computed concentrations of bicarbonate, sulfate and DOC are sensitive to most of the microbial parameters, including specific growth rates, half-saturation constants, proportionality coefficients and yield coefficients. Model results, however, are less sensitive to the yield coefficient of DOC to iron-reducer bacteria. The sensitivity analysis indicates that changes in fermentation microbial parameters affect the growth of the iron-reducer, thus confirming the interconnection of both microbial processes. Computed concentrations of bicarbonate and sulfate are found to be sensitive to changes in the initial concentration of POC and the boundary concentration of DOC, but they lack sensitivity to the initial concentration of DOC and the boundary concentration of POC. The explanation for such result is related to the fact that POC has a low mobility due to its large molecular weight. DOC, however, can migrate downwards. Although a coupled hydro-bio-geochemical 1-D model can reproduce the observed ''unexpected'' increase of concentrations of bicarbonate and sulfate at a depth of 70 m, further modeling work is required in order to obtain a similar conclusion under the more realistic two dimensional conditions of the fracture zone.

  6. Electrochemical DNA biosensor for detection of porcine oligonucleotides using ruthenium(II) complex as intercalator label redox

    SciTech Connect (OSTI)

    Halid, Nurul Izni Abdullah; Hasbullah, Siti Aishah; Heng, Lee Yook; Karim, Nurul Huda Abd [School of Chemical Sciences and Food Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan (Malaysia); Ahmad, Haslina; Harun, Siti Norain [Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor (Malaysia)

    2014-09-03T23:59:59.000Z

    A DNA biosensor detection of oligonucleotides via the interactions of porcine DNA with redox active complex based on the electrochemical transduction is described. A ruthenium(II) complex, [Ru(bpy){sub 2}(PIP)]{sup 2+}, (bpy = 2,2?bipyridine, PIP = 2-phenylimidazo[4,5-f[[1,10-phenanthroline]) as DNA label has been synthesized and characterized by 1H NMR and mass spectra. The study was carried out by covalent bonding immobilization of porcine aminated DNA probes sequences on screen printed electrode (SPE) modified with succinimide-acrylic microspheres and [Ru(bpy){sub 2}(PIP)]{sup 2+} was used as electrochemical redox intercalator label to detect DNA hybridization event. Electrochemical detection was performed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over the potential range where the ruthenium (II) complex was active. The results indicate that the interaction of [Ru(bpy){sub 2}(PIP)]{sup 2+} with hybridization complementary DNA has higher response compared to single-stranded and mismatch complementary DNA.

  7. Ultrasonic flow metering system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

  8. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

    1994-01-01T23:59:59.000Z

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  9. Zirconium vanadium chromium alloy

    DOE Patents [OSTI]

    Mendelsohn, M.H.; Gruen, D.M.

    1980-10-14T23:59:59.000Z

    A ternary intermetallic compound having the formula Zr(V/sub 1-x/Cr/sub x/)/sub 2/ where x is in the range of 0.01 to 0.90 is capable of reversibly sorbing hydrogen at temperatures ranging from room temperature to 200/sup 0/C, at pressures down to 10/sup -6/ torr. The compound is suitable for use as a hydrogen getter in low pressure, high temperature applications such as magnetic confinement fusion devices.

  10. Lateral flow strip assay

    DOE Patents [OSTI]

    Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

    2011-03-08T23:59:59.000Z

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  11. Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites

    SciTech Connect (OSTI)

    Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hallen, Richard T.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Swoboda, Robert G.

    2009-03-02T23:59:59.000Z

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan (Barnes and Voke 2006). The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Hanford Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP RPP WTP 467 (Fiskum et al. 2007), eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan. • Characterizing the homogenized sample groups. • Performing parametric leaching testing on each group for compounds of interest. • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on a filtration/leaching test performed using two of the eight waste composite samples. The sample groups examined in this report were the plutonium-uranium extraction (PUREX) cladding waste sludge (Group 3, or CWP) and reduction-oxidation (REDOX) cladding waste sludge (Group 4, or CWR). Both the Group 3 and 4 waste composites were anticipated to be high in gibbsite, thus requiring caustic leaching. WTP RPT 167 (Snow et al. 2008) describes the homogenization, characterization, and parametric leaching activities before benchtop filtration/leaching testing of these two waste groups. Characterization and initial parametric data in that report were used to plan a single filtration/leaching test using a blend of both wastes. The test focused on filtration testing of the waste and caustic leaching for aluminum, in the form of gibbsite, and its impact on filtration. The initial sample was diluted with a liquid simulant to simulate the receiving concentration of retrieved tank waste into the UFP2 vessel (< 10 wt% undissolved solids). Filtration testing was performed on the dilute waste sample and dewatered to a higher solids concentration. Filtration testing was then performed on the concentrated slurry. Afterwards, the slurry was caustic leached to remove aluminum present in the undissolved solid present in the waste. The leach was planned to simulate leaching conditions in the UFP2 vessel. During the leach, slurry supernate samples were collected to measure the dissolution rate of aluminum in the waste. After the slurry cooled down from the elevated leach temperature, the leach liquor was dewatered from the solids. The remaining slurry was rinsed and dewatered with caustic solutions to remove a majority of the dissolved aluminum from the leached slurry. The concentration of sodium hydroxide in the rinse solutions was high enough to maintain the solubility of the aluminum in the dewatered rinse solutions after dilution of the slurry supernate. Filtration tests were performed on the final slurry to compare to filtration performance before and after caustic leaching.

  12. Nox2 redox signaling maintains essential cell populations in the Bryan C Dickinson1, Joseph Peltier2, Daniel Stone2, David V Schaffer2, and Christopher J

    E-Print Network [OSTI]

    Schaffer, David V.

    Nox2 redox signaling maintains essential cell populations in the brain Bryan C Dickinson1, Joseph Peltier2, Daniel Stone2, David V Schaffer2, and Christopher J Chang1,3 1Department of Chemistry indicator for hydrogen peroxide (H2O2), we show that adult hippocampal stem/progenitor cells (AHPs) generate

  13. To be published in IEEE Aerospace Conference Proceedings, 2003, Cat No. 0-7803-7651-X/03/$17.00 2003 IEEE Planar REDOX and Conductivity Sensors

    E-Print Network [OSTI]

    Kounaves, Samuel P.

    To be published in IEEE Aerospace Conference Proceedings, 2003, Cat No. 0-7803-7651-X/03 are AeroRedox2C14 - 1 #12;To be published in IEEE Aerospace Conference Proceedings, 2003, Cat No. 0. BIOGRAPHIES 1. INTRODUCTION This paper extends the work reported at last year's IEEE Aerospace conference

  14. Structural basis of inter-domain electron transfer in Ncb5or, a redox enzyme implicated in diabetes and lipid metabolism

    E-Print Network [OSTI]

    Deng, Bin

    2011-12-31T23:59:59.000Z

    NADH cytochrome b5 oxidoreductase (Ncb5or) is a multi-domain redox enzyme found in all animal tissues and associated with the endoplasmic reticulum (ER). Ncb5or contains (from N-terminus to C terminus) a novel N-terminal region, the b5 domain (Ncb5...

  15. Back-reactions, short-circuits, leaks and other energy wasteful reactions in biological electron transfer: Redox tuning to survive life in O2

    E-Print Network [OSTI]

    Review Back-reactions, short-circuits, leaks and other energy wasteful reactions in biological Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland c s t r a c t The energy-converting redox enzymes perform productive reactions efficiently despite

  16. 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)

    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

    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.

  17. FINAL REPORT INTEGRATED DM1200 MELTER TESTING OF REDOX EFFECTS USING HLW AZ-101 AND C-106/AY-102 SIMULANTS VSL-04R4800-1 REV 0 5/6/

    SciTech Connect (OSTI)

    KRUGER AA; MATLACK KS; GONG W; BARDAKCI T; D'ANGELO NA; LUTZE W; BIZOT PM; CALLOW RA; BRANDYS M; KOT WK; PEGG IL

    2011-12-29T23:59:59.000Z

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of AZ-101 and C-106/AY-102 HLW simulants. The tests reported herein are a subset of three tests from a larger series of tests described in the Test Plan for the work; results from the remaining tests will be reported separately. Three nine day tests, one with AZ-101 and two with C-106/AY-102 feeds were conducted with variable amounts of added sugar to address the effects of redox. The test with AZ-101 included ruthenium spikes to also address the effects of redox on ruthenium volatility. One of tests addressed the effects of increased flow-sheet nitrate levels using C-106/AY-102 feeds. With high nitrate/nitrite feeds (such as WTP LAW feeds), reductants are required to prevent melt foaming and deleterious effects on glass production rates. Sugar is the baseline WTP reductant for this purpose. WTP HLW feeds typically have relatively low nitrate/nitrite content in comparison to the organic carbon content and, therefore, have typically not required sugar additions. However, HLW feed variability, particularly with respect to nitrate levels, may necessitate the use of sugar in some instances. The tests reported here investigate the effects of variable sugar additions to the melter feed as well as elevated nitrate levels in the waste. Variables held constant to the extent possible included melt temperature, bubbling rate, plenum temperature, cold cap coverage, the waste simulant composition, and the target glass composition. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW feeds with variable amounts of added sugar and increased nitrate levels; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and post test inspections of system components. The specific objectives (including test success criteria) of this testing, along with how each objective was met, are outlined in a table.

  18. Redox potential evolution of nitric species and plutonium in HNO{sub 3}-HNO{sub 2} system

    SciTech Connect (OSTI)

    Larabi-Gruet, N.; Gwinner, B.; Robin, R.; Fauvet, P. [CEA, DEN, DPC, SCCME, Lab Etud Corros Non Aqueuse, F-91191 Gif Sur Yvette, (France); Buravand, E. [CEA, DEN, DRCP, SE2A, Laboratoire d'Etudes de dissolution, F-30207 Bagnol/Ceze, (France)

    2012-07-01T23:59:59.000Z

    In France, the reprocessing process of spent fuel is carried out using the Purex process. The first chemical step of this process is the dissolution of the spent fuel in aqueous concentrated nitric acid. This dissolution solution is composed of many oxidizing species and it is necessary to understand the chemistry of these species to apprehend the behavior of structural materials. The redox potential is a useful discriminate variable to differentiate the effect of each species. In this framework, only the effect of NO{sub 3}{sup -}/HNO{sub 2} couple and PuO{sub 2}{sup 2+}/Pu{sup 4+} couple were investigated. These species were chosen because one is the main couple of medium and the other has a high standard potential. Their influence was investigated from the Nernst's equation. (authors)

  19. Redox control of electric melters with complex feed compositions. Part II: preliminary limits for radioactive waste melters

    SciTech Connect (OSTI)

    Bickford, D F; Diemer, Jr, R B; Iverson, D C

    1985-01-01T23:59:59.000Z

    Melter redox control is necessary for safe and continued melter operation. A combination of feed composition control, melter operational controls and monitors, and periodic determination of product glass redox state is sufficient to meet operating and safety requirements. Mossbauer spectroscopy, or other methods which determine the Fe(II)/Fe(III) ratio of the glass product, can be used to determine the oxidation state of the glass and thereby assess operating conditions. Slightly reducing conditions can eliminate radio-Ru volatility by suppressing the formation of RuO4. Reducing conditions also limit foaming resulting from the release of oxygen as transition metal oxides are dissolved in the melt. The calcination and partial combustion of organic compounds in the melter feed generates combustible mixtures of CO, H2 and benzene. The organics must be essentially completely incinerated to avoid the accumulation of combustible offgas mixtures, and prevent fouling of the equipment by soot and tars. Operation of the melter plenum above the autoignition temperature, metering in of purge air in excess of that required for complete combustion, and dilution by water vapor from reacted feed all preclude this occurrence in the melter. Prevention of dangerous offgas compositions after water vapor removal is assured by combustion in the melter, the addition of dilution air, and by continuous monitoring by % Lower Explosive Limit meters. Melter reducing power must be restricted to prevent formation of molten sulfides or selenides in the melter, and to prevent carburization and sulfidation attack of Inconel-690 melter components. Control of average oxygen partial pressure in the melter plenum is insufficient to assure prevention of localized attack of Inconel-690. An additional requirement is therefore necessary, that no soot or tarry substances be deposited on the Inconel-690.

  20. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05T23:59:59.000Z

    We demonstrate the possibility of a turbulent flow of electrons in graphene in the hydrodynamic region, by calculating the corresponding turbulent probability density function. This is used to calculate the contribution of the turbulent flow to the conductivity within a quantum Boltzmann approach. The dependence of the conductivity on the system parameters arising from the turbulent flow is very different from that due to scattering.

  1. Microelectromechanical flow control apparatus

    DOE Patents [OSTI]

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02T23:59:59.000Z

    A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.

  2. Development of vanadium-phosphate catalysts for methanol production by selective oxidation of methane. Quarterly technical progress report 10, July 1, 1995--September 31, 1995

    SciTech Connect (OSTI)

    McCormick, R.L.

    1995-12-07T23:59:59.000Z

    This document is the tenth quarterly technical progress report under Contract No. DE-AC22-92PC92110 {open_quotes}Development of Vanadium-Phosphate Catalysts for Methanol Production by Selective Oxidation of Methane{close_quotes}. Activities focused on testing of additional modified and promoted catalysts and characterization of these materials. Attempts at improving the sensitivity of our GC based analytical systems were also made with some success. Methanol oxidation studies were initiated. These results are reported. Specific accomplishments include: (1) Methane oxidation testing of a suite of catalysts promoted with most of the first row transition metals was completed. Several of these materials produced low, difficult to quantify yields of formaldehyde. (2) Characterization of these materials by XRD and FTIR was performed with the goal of correlating activity and selectivity with catalyst properties. (3) We began to characterize catalysts prepared via modified synthesis methods designed to enhance acidity using TGA measurements of acetonitrile chemisorption and methanol dehydration to dimethyl ether as a test reaction. (4) A catalyst prepared in the presence of naphthalene methanol as a structural disrupter was tested for activity in methane oxidation. It was found that this material produced low yields of formaldehyde which were difficult to quantify. (5) Preparation of catalysts with no Bronsted acid sites. This was accomplished by replacement of exchangeable protons with potassium, and (6) Methanol oxidation studies were initiated to provide an indication of catalyst activity for decomposition of this desired product and as a method of characterizing the catalyst surface.

  3. copyrisht@ree2bythen-""i"",,R3il:'J[$H#"",i*tTy"t"*r1"'J?rt;""mission orthecopyrightowner. Toward Orthogonal Self-Assembly of Redox Active

    E-Print Network [OSTI]

    Prentiss, Mara

    Orthogonal Self-Assembly of Redox Active Molecules on Pt and Au: Selective Reaction of Disulfide with Au.; Uphaus,R. A. Microchem.J.1990,42, 44, and referencestherein on viologen monolayer electrochemistry. (5

  4. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  5. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06T23:59:59.000Z

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  6. Sequestration of terrigenous organic carbon on the northern California shelf : role of hyperpycnal flows

    E-Print Network [OSTI]

    Moeremans, Raphaële E.

    2011-01-01T23:59:59.000Z

    cores have not experienced diagenesis from deep burial andwith redox-related diagenesis. Maxima in Fe/Ti ratio could

  7. EXPERIMENTAL INVESTIGATION OF Ti and Fe VALENCE IN CHONDRULE-LIKE MELTS DURING COOLING UNDER CHANGING REDOX CONDITIONS AT LOW PARTIAL PRESSURES. S. B. Simon1

    E-Print Network [OSTI]

    Grossman, Lawrence

    . This idea is being tested experimentally. Initial results were re- ported by [3]; here we report results CHANGING REDOX CONDITIONS AT LOW PARTIAL PRESSURES. S. B. Simon1 , J. R. Beckett2 , S. R. Sutton1,3 and L melted on Fe loops. Three runs are reported here: an isothermal run (I6) at 1400°C for 66 h at 2.75 log

  8. Synthesis and charge-transport properties of polymers derived from the oxidation of 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridium Bis(hexafluorophosphate) and demonstration of pH-sensitive microelectrochemical transistor derived from the redox properties of a conventional redox center

    SciTech Connect (OSTI)

    Shu, C.F.; Wrighton, M.S.

    1988-09-08T23:59:59.000Z

    This article describes the synthesis and electrochemical properties of redox polymers, having a polypyrrole backbone and viologen subunits, derived from oxidative electropolymerization of 1-methyl-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-Me/sup 2 +/) and 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-H/sup 2 +/). Closely spaced (approx. 1.5 ..mu..M) Au microelectrode arrays (approx. 2.5 ..mu..m wide /times/ 50 ..mu..m long /times/ 0.1 ..mu..m high) modified with the polymers can be used to study aspects of the charge-transport behavior of the viologen redox system. Poly(P-V-Me/sup 2 +/) have been used to investigate the characteristics of microelectrochemical transistors based on a viologen redox center and a similar redox center, protonated, monoquaternized bipyridinium, which is pH dependent. The interesting properties from poly(P-V-Me/sup 2 +/) and poly(P-V-H/sup 2 +/) stem from behavior of the pendant viologen redox centers. The device based on poly(P-V-Me/sup 2 +/) has a narrow region (approx. 200 mV) of gate voltage, V/sub G/, where the source-drain current, I/sub D/, is nonzero and has a sharp, pH-independent peak in the I/sub D/-V/sub G/ plot at approx. 0.53 V versus SCE associated with the reversible, one-electron reduction of viologen. This result is consistent with electron self-exchange between redox centers being the mechanism for charge transport. The device based on poly(P-V-H/sup 2 +/) shows a pH-dependent I/sub D/ at fixed V/sub G/, as expected from the electrochemical behavior from reversible protonation of the terminal N of the bipyridinium group of poly(P-V-H/sup 2 +/). The microelectrochemical transistor based on poly(P-V-H/sup 2 +/) illustrates the design of chemically sensitive, molecule-based devices using conventional redox materials.

  9. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01T23:59:59.000Z

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  10. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    Present-day networks are being challenged by dramatic increases in bandwidth demand of emerging applications. We will explore a new transport, ldquooptical flow switchingrdquo, that will enable significant growth and ...

  11. Olefin Autoxidation in Flow

    E-Print Network [OSTI]

    Neuenschwander, Ulrich

    Handling hazardous multiphase reactions in flow brings not only safety advantages but also significantly improved performance, due to better mass transfer characteristics. In this paper, we present a continuous microreactor ...

  12. The role of nanopores on U(VI) sorption and redox behavior in U(VI)-contaminated subsurface sediments

    SciTech Connect (OSTI)

    Xu, Huifang; Roden, Eric E.; Kemner, Kenneth M.; Jung, Hun-Bok; Konishi, Hiromi; Boyanov, Maxim; Sun, Yubing; Mishra, Bhoopesh

    2013-10-16T23:59:59.000Z

    Most reactive surfaces in clay-dominated sediments are present within nanopores (pores of nm dimension). The behavior of geological fluids and minerals in nanopores is significantly different from those in normal non-nanoporous environments. The effect of nanopore surfaces on U(VI) sorption/desorption and reduction is likely to be significant in clay-rich subsurface environments. Our research results from both model nanopore system and natural sediments from both model system (synthetic nanopore alumina) and sediments from the ORNL Field Research Center prove that U(VI) sorption on nanopore surfaces can be greatly enhanced by nanopore confinement environments. The results from the project provide advanced mechanistic, quantitative information on the physiochemical controls on uranium sorption and redox behavior in subsurface sediments. The influence of nanopore surfaces on coupled uranium sorption/desorption and reduction processes is significant in virtually all subsurface environments, because most reactive surfaces are in fact nanopore surfaces. The results will enhance transfer of our laboratory-based research to a major field research initiative where reductive uranium immobilization is being investigated. Our results will also provide the basic science for developing in-situ colloidal barrier of nanoporous alumina in support of environmental remediation and long term stewardship of DOE sites.

  13. Subsurface microbial community structure correlates with uranium redox phases during in situ field manipulation in a contaminated aquifer

    SciTech Connect (OSTI)

    Kostka, Joel [Florida State University; Green, Stefan [Florida State University, Tallahassee; Wu, Wei-min [Stanford University; Criddle, Craig [Stanford University; Watson, David B [ORNL; Jardine, Philip M [ORNL

    2009-07-01T23:59:59.000Z

    Long-term field manipulation experiments investigating the effects of subsurface redox conditions on the fate and transport of soluble uranium(VI) were conducted over a 3 year period at the Oak Ridge Integrated Field Research Center (OR-IFRC) in Oak Ridge, TN. In the highly contaminated source zone, introduction of ethanol to the subsurface stimulated native denitrifying, sulfate-reducing, iron-reducing and fermentative microorganisms and reduced U to below 0.03 mg/L. Subsequently, oxygen and nitrate were experimentally re-introduced into the subsurface to examine the potential for re-oxidation and re-mobilization of U(IV). Introduction of oxygen or nitrate caused changes in subsurface geochemistry and re-oxidation of U. After reoxidation, the subsurface experienced several months of starvation conditions before ethanol injection was restored to reduce the treatment zone. Subsurface microorganisms were characterized by community fingerprinting, targeted population analyses, and quantitative PCR of key functional groups in 50 samples taken during multiple phases of field manipulation. Statistical analysis confirmed the hypothesis that the microbial community would co-vary with the shifts in the subsurface geochemistry. The level of hydraulic connectivity of sampling wells to the injection well was readily tracked by microbial community analysis. We demonstrate quantitatively that specific populations, especially Desulfosporosinus, are heavily influenced by geochemical conditions and positively correlate with the immobilization of uranium. Following nitrate reoxidation, populations of Fe(II)-oxidizing, nitrate reducing organisms (Thiobacillus) showed an increase in relative abundance.

  14. Electrostatic binding of bicarbonate and formate in viologen-based redox polymers: importance in catalytic reduction of bicarbonate to formate

    SciTech Connect (OSTI)

    Andre, J.F.; Wrighton, M.S.

    1985-12-04T23:59:59.000Z

    The relative importance of electrostatic binding of CO3H and HCO2 in a redox polymer derived from an N,N'-dialkyl-4,4'-bipyridinium monomer has been investigated by Fourier transform infrared (FTIR) spectroscopy. At 298 K and a total concentration of C-containing species of 0.1 M the two species are equally firmly bound in a polymer immobilized on a single-crystal Si electrode surface. When the concentration of C-containing species is 1.0 M, the CO3H ion is more firmly bound by about a factor of 2.5, and at a total concentration of 3.0 M the CO3H ion is about 7 times more firmly bound than the HCO2 ion. The HCO2 and Cl anions are equally firmly bound at 1.0 M total anion concentration. On the basis of the lack of change in the cyclic voltammetry response of a derivatized electrode in 1.0 M Na(CO3H) or Na(HCO2) compared to 1.0 M NaCl, the exchange rate of the C-containing anions does not appear to be a factor that would limit the rate of reduction of the CO3H ion at an electrode modified with the polymer and impregnated with Pd(0).

  15. Photoinduced and redox-induced transmembrane processes with vesicle-stabilized colloidal cadmium sulfide and multicharged viologen derivatives

    SciTech Connect (OSTI)

    Tricot, Y.M.; Porat, Z.; Manassen, J. (Weizmann Inst. of Science, Rehovot (Israel))

    1991-04-18T23:59:59.000Z

    Colloidal cadmium sulfide (CdS) and methylviologen (MV{sup 2+}) or new viologen derivatives carrying more positive charges were placed at specific sites of dihexadecyl phosphate (DHP) vesicles. Benzyl alcohol was used as a sacrificial electron donor to promote reduction of the viologens by photoexcited CdS colloid majority carriers. Transmission electron microscopy, {sup 13}C nuclear magnetic resonance, and differential scanning calorimetry were used for physical characterization. Photochemical events were followed by in situ optical and electrochemical monitoring. Redox-induced transmembrane diffusion, which had been found with MV{sup 2+}, could be reduced by a factor 18 by using a triply charged viologen derivative and by a further factor of 30 in a configuration involving transmembrane electron transfer. In that case the quantum yield was ca. 0.05 at 410 nm, while virtually no reduced viologen leaking could be observed during at least 10 min. Physical evidence was found for a partial penetration of the CdS colloids into the DHP membrane.

  16. Photoinduced redox reactions in aqueous micelles. Quenching, back-reaction, and competing processes for tetraanionic porphyrins with alkylviologens

    SciTech Connect (OSTI)

    Schmehl, R.H.; Whitten, D.G.

    1981-11-12T23:59:59.000Z

    Photoinduced redox reactions employing the anionic porphyrins meso-tetrakis(p-sulfonatophenyl)porphyrin (1) and its palladium(II) complex (2) as excited substrates and various alkylviologens as quenchers have been studied in homogeneous aqueous solution and in the presence of the charged detergents sodium dodecyl sulfate (SDS) and cetyltrimethylammonium chloride (CTAC) above the critical micelle concentration (cmc). In homogeneous solution strong ground-state association between the porphyrins and the viologens occurs; even dynamic quenching processes result in no separation of electron transfer product ions. Addition of either SDS or CTAC reduces the quenching rates but allows the detection of product ions surviving up to ca. 100 ms in some cases. The back-reactions are sensitive to a variety of factors including added electrolyte, hydrophobicity of the viologen and its one-electron reduction product, and the charge on the surfactant. The long-lived products can be selectively intercepted by a variety of reagents. In the case of quenching of the palladium porphyrin (2) by methylviologen, the oxidized porphyrin can be reduced by iodide while the reduced viologen can be oxidized via either a colloidal catalyst or reaction with molecular oxygen. These reactions illustrate the possibility for obtaining net chemical conversion in a process whereby both the light-absorbing substrate and the quencher are recycled.

  17. Conjugate flow action functionals

    SciTech Connect (OSTI)

    Venturi, Daniele, E-mail: daniele-venturi@brown.edu [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)] [Division of Applied Mathematics, Brown University, Rhode Island 02912 (United States)

    2013-11-15T23:59:59.000Z

    We present a new general framework to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gâteaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

  18. Section 13: Flow control 1 Section 13: Flow control

    E-Print Network [OSTI]

    Kohlenbach, Ulrich

    Geometries for Energyefficient Flow Around Bodies Abstract 14:30 ­ 14:50: Elfriede Friedmann (Universität

  19. [Unsegmented continuous-flow sample processing and electrochemical detection of gaseous species

    SciTech Connect (OSTI)

    Mottola, H.A.

    1991-01-01T23:59:59.000Z

    Goals were a continuous-flow, unsegmented, all-gas carrier and/or a segmented liquid/gas interface system for sample introduction and transport to detection/determination point; a regenerable electrode probe base on redox reactions of Fe(II) and Fe(III) complexes with 1, 10-phenanthroline and related ligands; and amperometric/coulometric current measurements providing analyte signals. Gases to be detected included NO[sub x] and SO[sub 2]. This report is divided into 3 parts: preparation of new ligands of 1,10-phenanthroline family; glassy carbon surfaces coated with polymeric films prepared from monomeric units of tris[5-amino-1,10-phenanthroline]iron(II); and sulfite oxidase/hexacyanoferrate modified C paste electrode.

  20. Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry

    E-Print Network [OSTI]

    Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry using energy flow method Azimuthal angle distribution at Q2 >100 GeV2 Energy flow method.Ukleja on behalf of the ZEUS Collaboration #12; Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I

  1. Piezoelectric axial flow microvalve

    SciTech Connect (OSTI)

    Gemmen, Randall; Thornton, Jimmy; Vipperman, Jeffrey S.; Clark, William W.

    2007-01-09T23:59:59.000Z

    This invention is directed to a fuel cell operable with a quantity of fuel and a quantity of an oxidizer to produce electrical power, the fuel cell including a fuel cell body including a labyrinth system structured to permit the fuel and the oxidizer to flow therethrough; at least a first catalyst in fluid communication with the labyrinth; and at least a first microvalve operably disposed within at least a portion of the labyrinth. The microvalve utilizes a deflectable member operable upon the application of a voltage from a voltage source. The microvalve includes an elongated flow channel formed therein and extending substantially longitudinally between the first and second ends to permit substantially longitudinal flow of the fluid therethrough and between the first and second ends; and the deflectable member disposed on the valve body, the deflectable member including at least a first piezoelectric portion that is piezoelectrically operable to deflect the deflectable member between an open position and a closed position upon the application of a voltage, the deflectable member in the closed position being operable to resist the flow of the fluid through the flow channel.

  2. Gaseous Flows in Galaxies

    E-Print Network [OSTI]

    F. Combes

    2007-09-02T23:59:59.000Z

    The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers gravitational instabilities, and the corresponding non-axisymmetric patterns produce gravity torques, which mediate these angular momentum exchanges. When a srong bar pattern develops with the same pattern speed all over the disk, only gas inside corotation can flow towards the center. But strong bars are not long lived in presence of gas, and multiple-speed spiral patterns can develop between bar phases, and help the galaxy to accrete external gas flowing from cosmic filaments. The gas is then intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The various time-scales of these gaseous flows are described.

  3. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20T23:59:59.000Z

    I discuss the multiphase nature of the intracluster medium whose neglect can lead to overestimates of the baryon fraction of clusters by up to a factor of two. The multiphase form of the cooling flow equations are derived and reduced to a simple form for a wide class of self-similar density distributions. It is shown that steady-state cooling flows are \\emph{not} consistent with all possible emissivity profiles which can therefore be used as a test of the theory. In combination, they provide strong constraints on the mass distribution within the cooling radius.

  4. Viologen (2+/1+) and viologen(1+/0) electron-self-exchange reactions in a redox polymer

    SciTech Connect (OSTI)

    Dalton, E.F.; Murray, R.W. (Univ. of North Carolina, Chapel Hill (United States))

    1991-08-08T23:59:59.000Z

    An analysis is given of the electron-self-exchange reactions responsible for the steady-state redox conductivity of thin films of the electropolymerized monomer N,N{prime}-bis(3-pyrrol-1-yl-propyl)-4,4{prime}-bipyridinium tetrafluoroborate, sandwiched between two electrodes. Concentration-gradient-driven electron self-exchange in the liquid-acetonitrile-bathed viologen(2+/1+) mixed-valent state of this polymer, k{sub ex} = 8 {times} 10{sup 3} M{sup {minus}1}s{sup {minus}1}, is much slower than that for the viologen (1+/0) mixed-valent state, k{sub ek} = 1.6 {times} 10{sup 5} M{sup {minus}1} s{sup {minus}1}, which has a smaller activation barrier. Neither self-exchange reaction responds to use of alternative counteranions except that both rates decrease in polymer containing tosylate counterions. The rate constant found for the electrical-gradient-driven viologen (1+/0) electron self-exchange, k{sub ex} = 1.1 {times} 10{sup 5} M{sup {minus}1} s{sup {minus}1}, observed in dry, N{sub 2}-bathed polymer where ClO{sub 4}{sup {minus}} counterion mobility is quenched, is nearly the same as the acetonitrile-bathed value. The rate constants appear to be dominated by characteristics of the polymer phase rather than the bathing environment of the polymer. Estimates are made of the counteranion diffusivity in acetonitrile-bathed films and of how it effects transient electron transport measurements.

  5. Redox Exchange Induced MnO2 Nanoparticle Enrichment in Poly(3,4-ethylenedioxythiophene) Nanowires for Electrochemical Energy Storage

    SciTech Connect (OSTI)

    Liu, R; Duay, Jonathon; Lee, Sang Bok

    2010-01-01T23:59:59.000Z

    MnO{sub 2} nanoparticle enriched poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires are fabricated by simply soaking the PEDOT nanowires in potassium permanganate (KMnO{sub 4}) solution. The structures of these MnO{sub 2} nanoparticle enriched PEDOT nanowires are characterized by SEM and TEM, which show that the MnO{sub 2} nanoparticles have uniform sizes and are finely dispersed in the PEDOT matrix. The chemical constituents and bonding of these composite nanowires are characterized by energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, and infrared spectroscopy, which indicate that the formation and dispersion of these MnO{sub 2} nanoparticles into the nanoscale pores of the PEDOT nanowires are most likely triggered by the reduction of KMnO{sub 4} via the redox exchange of permanganate ions with the functional group on PEDOT. Varying the concentrations of KMnO{sub 4} and the reaction time controls the loading amount and size of the MnO{sub 2} nanoparticles. Cyclic voltammetry and galvanostatic charge?discharge are used to characterize the electrochemical properties of these MnO{sub 2} nanoparticle loaded PEDOT nanowires. Due to their extremely high exposed surface area with nanosizes, the pristine MnO{sub 2} nanoparticles in these MnO{sub 2} nanoparticle enriched PEDOT nanowires show very high specific capacitance (410 F/g) as the supercapacitor electrode materials as well as high Li+ storage capacity (300 mAh/g) as cathode materials of Li ion battery, which boost the energy storage capacity of PEDOT nanowires to 4 times without causing excessive volume expansion in the polymer. The highly conductive and porous PEDOT matrix facilitates fast charge/discharge of the MnO{sub 2} nanoparticles and prevents them from agglomerating. These synergic properties enable the MnO{sub 2} nanoparticle enriched PEDOT nanowires to be promising electrode materials for supercapacitors and lithium ion batteries.

  6. CX-006145: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    The Painesville Municipal Power Vanadium Redox Battery Demonstration ProgramCX(s) Applied: B3.6Date: 07/14/2011Location(s): Painesville, OhioOffice(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory

  7. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01T23:59:59.000Z

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.

  8. AGN and Cooling Flows

    E-Print Network [OSTI]

    James Binney

    2001-03-23T23:59:59.000Z

    For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming under increasing pressure observationally. A small number of enthusiasts have argued for a radically different interpretation of the data, but had little impact on prevailing opinion because the unsteady heating picture that they advocate is extremely hard to work out in detail. Here I explain why it is difficult to extract robust observational predictions from the heating picture. Major problems include the variability of the sources, the different ways in which a bi-polar flow can impact on X-ray emission, the weakness of synchrotron emission from sub-relativistic flows, and the sensitivity of synchrotron emission to a magnetic field that is probably highly localized.

  9. Aqueous Transition Metal Cations as Impurities in a Wide Gap Oxide: The Cu^2+/Cu^1+ and Ag^2+/Ag^1+ Redox Couples Revisited

    E-Print Network [OSTI]

    Liu, Xiandong; Cheng, Jun; Sprik, Michiel

    2014-11-11T23:59:59.000Z

    of 10ps. The longitudinal relaxation is more than a magnitude faster. Results and analysis Gas-phase Table 1 lists the calculated M-O bond lengths in the four gas-phase complexes we have investigated (see fig. 1). One can see that for the same number... containing a fraction of Hartree-Fock exchange. These calculations make use of recent progress in DFTMD technology enabling us to include sp core polarization and Hartree-Fock exchange in condensed phase model systems. Keywords Aqueous redox chemistry...

  10. Coupling free flow / porous-medium flow General idea

    E-Print Network [OSTI]

    Cirpka, Olaf Arie

    equation t (v) + div (vv ) - div(v) + p - g - qv = 0 Darcy flow equation t (S) - div K (p - g) - qpmT transport equation t (X) + div (vX - DsteamX) = qsteam 16/14 #12;Backup additional Darcy flow equations-Stokes 1 phase, 2 components, temperature sharp interface porous-medium / Darcy flow 2 phases, 2 component

  11. Status of cross-section data for gas production from vanadium and {sup 26}AL from silicon carbide in a D-T fusion reactor.

    SciTech Connect (OSTI)

    Gomes, I. C.

    1998-08-11T23:59:59.000Z

    Current designs of fusion-reactor systems seek to use radiation-resistant, low-activation materials that support long service lifetimes and minimize radioactive-waste problems after decommissioning. Reliable assessment of fusion materials performance requires accurate neutron-reaction cross sections and radioactive-decay constants. The problem areas usually involve cross sections since decay parameters tend to be better known. The present study was motivated by two specific questions: (i) Why are the {sup 51}V(n,np){sup 50}Ti cross section values in the ENDF/B-VI library so large (a gas production issue)? (ii) How well known are the cross sections associated with producing 7.4 x 10{sup 5} y {sup 26}Al in silicon carbide by the process {sup 28}Si(n,np+d){sup 27} Al(n,2n){sup 26}Al (a long-lived radioactivity issue)? The energy range 14-15 MeV of the D-T fusion neutrons is emphasized. Cross-section error bars are needed so that uncertainties in the gas and radioactivity generated over the lifetime of a reactor can be estimated. We address this issue by comparing values obtained from prominent evaluated cross-section libraries. Small differences between independent evaluations indicate that a physical quantity is well known while the opposite signals a problem. Hydrogen from {sup 51}V(n,p){sup 51}Ti and helium from {sup 51}V(n,{alpha}){sup 48}Sc are also important sources of gas in vanadium, so they too were examined. We conclude that {sup 51}V(n,p){sup 51}Ti is adequately known but {sup 51}V(n,np+d){sup 50}Ti is not. The status for helium generation data is quite good. Due to recent experimental work, {sup 27}Al(n,2n){sup 26}Al seems to be fairly well known. However, the situation for {sup 28}Si(n,np+d){sup 27}Al remains unsatisfactory.

  12. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12;MESSAGE FLOW

  13. Radial flow pulse jet mixer

    DOE Patents [OSTI]

    VanOsdol, John G.

    2013-06-25T23:59:59.000Z

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  14. Flow (2008) Director: Irena Salina

    E-Print Network [OSTI]

    Hemmers, Oliver

    2008-01-01T23:59:59.000Z

    Flow (2008) Director: Irena Salina Run Time: 93 min. Summary: ,Irena Salina's documentary film://documentaryfilms.suite101.com/article.cfm/desperate_for_water_irena_salinas_movie_flow No Dumb Questions (2001) Director

  15. Ricci flow and quantum theory

    E-Print Network [OSTI]

    Robert Carroll

    2007-11-05T23:59:59.000Z

    We show some relations between Ricci flow and quantum theory via Fisher information and the quantum potential.

  16. Poly(pyridine)ruthenium(II)-photoinduced redox reactions of bipyridinium cations, poly(pyridine)rhodium complexes, and osmium ammines

    SciTech Connect (OSTI)

    Creutz, C.; Keller, A.D.; Sutin, N.; Zipp, A.P.

    1982-06-30T23:59:59.000Z

    The quenching of *RuL/sub 3//sup 2 +/ (L is a 2,2'-bipyridine or 1,10-phenanthroline derivative) emissions by three classes of oxidants Q has been examined. The results are discussed in terms of the Marcus electron-transfer model recast in a preequilibrium formalism. Substituted bipyridinium cations (methyl viologen and related compounds) undergo thermodynamically favorable reduction with a driving force ranging from 0.1 to 0.7 eV and rate constants in the range (0.4-2.0) x 10/sup 9/ M/sup -1/s/sup -1/, consistent with a diffusion rate constant of 2.0 x 10/sup 9/ M/sup -1/s/sup -1/ and an exchange rate constant of approx.10/sup 6/ M/sup -1/s/sup -1/ for the Q-Q couples. The yields of the separated redox products RuL/sub 3//sup 3 +/ and Q/sup -/ (typically 0.1 mol einstein/sup -1/ per quenching act) require K/sub 30/, the ''intramolecular'' back-reaction rate constant (to re-form ground-state RuL/sub 3//sup 2 +/ and Q), to be (2-4) x 10/sup 10/ s/sup -1/. Since K/sub 30/ increases weakly with driving force in this series, there is no evidence for inverted behavior despite the fact the ..delta..G/sup 0//sub 30/ is approx.-2 eV. With Q = Rh(4,4'-(CH/sub 3/)/sub 2/bpy)/sub 3//sup 3 +/, the quenching rate constants, k/sub q/ = (0.001-1.0) x 10/sup 9/ M/sup -1/s/sup -1/, exhibit a great sensitivity to the reducing power of *RuL/sub 3//sup 2 +/ and have been fitted to k/sub 11/ approx. = 2 x 10/sup 9/ M/sup -1/s/sup -1/ and E/sup 0//sub Q,Q/sup -// = -0.97 V for the RhL/sub 3//sup 3 +/-RhL/sub 3//sup 2 +/ couple. This E/sup 0/ value is strikingly similar to that (-0.9 V vs. aqueous SCE) obtained via cyclic voltammetry in acetonitrile. The cyclic voltammetry of the RhL/sub 3//sup 3 +/ complexes in water has been reexamined, and it is concluded that the irreversibility observed is due to ligand loss from rhodium(I).

  17. The Big Flow

    E-Print Network [OSTI]

    P. Sikivie

    2001-12-04T23:59:59.000Z

    The late infall of cold dark matter onto an isolated galaxy, such as our own, produces streams and caustics in its halo. The outer caustics are topological spheres whereas the inner caustics are rings. The self-similar model of galactic halo formation predicts that the caustic ring radii $a_n$ follow the approximate law $a_n \\sim 1/n$. In a study of 32 extended and well-measured external galactic rotation curves evidence was found for this law. In the case of the Milky Way, the locations of eight sharp rises in the rotation curve fit the prediction of the self-similar model at the 3% level. Moreover, a triangular feature in the IRAS map of the galactic plane is consistent with the imprint of a ring caustic upon the baryonic matter. These observations imply that the dark matter in our neighborhood is dominated by a single flow. Estimates of that flow's density and velocity vector are given.

  18. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01T23:59:59.000Z

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  19. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09T23:59:59.000Z

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  20. Single-Crystalline Vanadium Dioxide Nanowires with Rectangular Cross Beth S. Guiton, Qian Gu, Amy L. Prieto, Mark S. Gudiksen, and Hongkun Park*

    E-Print Network [OSTI]

    Heller, Eric

    were placed in a quartz boat in the center of a horizontal tube furnace, and temperature (T), pressure (P), evaporation time (t), and argon carrier gas flow rate (kflow) were controlled to obtain

  1. Determination of redox reaction rates and –orders by in-situ liquid cell electron microscopy of Pd and Au solution growth

    SciTech Connect (OSTI)

    Sutter, Eli A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sutter, Peter W. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-12-03T23:59:59.000Z

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. By comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  2. Determination of redox reaction rates and –orders by in-situ liquid cell electron microscopy of Pd and Au solution growth

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sutter, Eli A.; Sutter, Peter W.

    2014-12-03T23:59:59.000Z

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pdmore »deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. By comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.« less

  3. Determination of redox reaction rates and –orders by in-situ liquid cell electron microscopy of Pd and Au solution growth

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sutter, Eli A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sutter, Peter W. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-12-03T23:59:59.000Z

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. By comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  4. [Unsegmented continuous-flow sample processing and electrochemical detection of gaseous species]. Final report, March 1, 1985--February 28, 1991

    SciTech Connect (OSTI)

    Mottola, H.A.

    1991-12-31T23:59:59.000Z

    Goals were a continuous-flow, unsegmented, all-gas carrier and/or a segmented liquid/gas interface system for sample introduction and transport to detection/determination point; a regenerable electrode probe base on redox reactions of Fe(II) and Fe(III) complexes with 1, 10-phenanthroline and related ligands; and amperometric/coulometric current measurements providing analyte signals. Gases to be detected included NO{sub x} and SO{sub 2}. This report is divided into 3 parts: preparation of new ligands of 1,10-phenanthroline family; glassy carbon surfaces coated with polymeric films prepared from monomeric units of tris[5-amino-1,10-phenanthroline]iron(II); and sulfite oxidase/hexacyanoferrate modified C paste electrode.

  5. Complex Flow Workshop Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuildingCoalComplex Flow Workshop Report January 17-18, 2012 University

  6. Non-axisymmetric Flows

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire Solar541,9337,2AprilBig EddyNobelNon-axisymmetric Flows and

  7. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30T23:59:59.000Z

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  8. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)

    1993-01-01T23:59:59.000Z

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  9. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01T23:59:59.000Z

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  10. Pyrite oxidation in saturated and Unsaturated Porous Media Flow: AComparison of alternative mathematical modeling approaches

    SciTech Connect (OSTI)

    Xu, Tianfu; White, Stephen P.; Pruess, Karsten

    1998-02-15T23:59:59.000Z

    Pyrite (FeS{sub 2}) is one of the most common naturally occurring minerals that is present in many subsurface environments. It plays an important role in the genesis of enriched ore deposits through weathering reactions, is the most abundant sulfide mineral in many mine tailings, and is the primary source of acid drainage from mines and waste rock piles. The pyrite oxidation reaction serves as a prototype for oxidative weathering processes with broad significance for geoscientific, engineering, and environmental applications. Mathematical modeling of these processes is extremely challenging because aqueous concentrations of key species vary over an enormous range, oxygen inventory and supply are typically small in comparison to pyrite inventory, and chemical reactions are complex, involving kinetic control and microbial catalysis. We present the mathematical formulation of a general multi-phase advective-diffusive reactive transport model for redox processes. Two alternative implementations were made in the TOUGHREACT and TOUGH2-CHEM simulation codes which use sequential iteration and simultaneous solution, respectively. The simulators are applied to reactive consumption of pyrite in (1) saturated flow of oxidizing water, and (2) saturated-unsaturated flow in which oxygen transport occurs in both aqueous and gas phases. Geochemical evolutions predicted from different process models are compared, and issues of numerical accuracy and efficiency are discussed.

  11. Active combustion flow modulation valve

    DOE Patents [OSTI]

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W

    2013-09-24T23:59:59.000Z

    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  12. Pertechnetate (TcO4-) reduction by reactive ferrous iron forms in naturally anoxic, redox transition zone sediments from the Hanford Site, USA

    SciTech Connect (OSTI)

    Peretyazhko, Tetyana; Zachara, John M.; Kukkadapu, Ravi K.; Heald, Steve M.; Kutnyakov, Igor V.; Resch, Charles T.; Arey, Bruce W.; Wang, Chong M.; Kovarik, Libor; Phillips, Jerry L.; Moore, Dean A.

    2012-09-01T23:59:59.000Z

    Technetium is an important environmental contaminant introduced by the processing and disposal of irradiated nuclear fuel and atmospheric nuclear tests. Under oxic conditions technetium is soluble and exists as pertechnatate anion (TcO4-), while under anoxic conditions Tc is usually insoluble and exists as precipitated Tc(IV). Here we investigated abiotic Tc(VII) reduction in mineralogically heterogeneous, Fe(II)-containing sediments. The sediments were collected from a 55 m borehole that sampled a semi-confined aquifer at the Hanford Site, USA that contained a dramatic redox transition zone. One oxic facies (18.0-18.3 m) and five anoxic facies (18.3-18.6 m, 30.8-31.1 m, 39.0-39.3 m, 47.2-47.5 m and 51.5-51.8 m) were selected for this study. Chemical extractions, X-ray diffraction, electron microscopy, and Mössbauer spectroscopy were applied to characterize the Fe(II) mineral suite that included: Fe(II)-phyllosilicates, pyrite, magnetite and siderite. The Fe(II) mineral phase distribution differed between the sediments. Sediment suspensions were adjusted to the same 0.5 M HCl extracted Fe(II) concentration (0.6 mM) for Tc(VII) reduction experiments. Aqueous Fe was low in all sediment suspensions (<2 ?M) and below the Fe(II)aq detection limit (10 ?M). Technetium(VII) reduction occurred in all anoxic sediments at depths greater than 18.3 m and reaction time differed significantly between the sediments (8-219 d). Mössbauer analysis of the Tc-reacted, 30.8-31.1 m sediment confirmed that Tc(VII) was reduced by solid-phase Fe(II), with siderite and Fe(II)-containing phyllosilicates implicated as redox reactive phases. Technetium-XAS analysis demonstrated that Tc associated with sediments was in the Tc(IV) valence state and immobilized as clusters of a TcO2·nH2O-like phase. The speciation of redox product Tc(IV) was not affected by reduction rate or Fe(II) mineralogy.

  13. What's Next for Vanadium Dioxide?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilizeRuraltheWelcome NationalEngineerWhatWhatWhat

  14. Subsurface Flow and Transport | EMSL

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

    subsurface related to contaminant transport, carbon cycling, enhanced oil recovery and carbon dioxide sequestration. See a complete list of Subsurface Flow and Transport...

  15. Rényi entropy flows from quantum heat engines

    E-Print Network [OSTI]

    Mohammad H. Ansari; Yuli V. Nazarov

    2015-03-20T23:59:59.000Z

    We evaluate Renyi entropy flows from generic quantum heat engines (QHE) to a weakly-coupled probe environment kept in thermal equilibrium. We show that the flows are determined not only by heat flow but also by a quantum coherent flow that can be separately measured in experiment apart from the heat flow measurement. The same pertains to Shanon entropy flow. This appeals for a revision of the concept of entropy flows in quantum nonequlibrium thermodynamics.

  16. Network Flow Optimization under Uncertainty

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Network model in words Minimize the cost of satisfying demands for electric energy By: imports, exports and electricity Subject to: conservation of energy flows (net after losses), lower and upper bounds on flows is a reactive approach: how would the optimal solution have changed if I'd only known? · Proactive approaches

  17. Wavy flow cooling concept for turbine airfoils

    DOE Patents [OSTI]

    Liang, George (Palm City, FL)

    2010-08-31T23:59:59.000Z

    An airfoil including an outer wall and a cooling cavity formed therein. The cooling cavity includes a leading edge flow channel located adjacent a leading edge of the airfoil and a trailing edge flow channel located adjacent a trailing edge of the airfoil. Each of the leading edge and trailing edge flow channels define respective first and second flow axes located between pressure and suction sides of the airfoil. A plurality of rib members are located within each of the flow channels, spaced along the flow axes, and alternately extending from opposing sides of the flow channels to define undulating flow paths through the flow channels.

  18. Vertical flow chemical detection portal

    DOE Patents [OSTI]

    Linker, K.L.; Hannum, D.W.; Conrad, F.J.

    1999-06-22T23:59:59.000Z

    A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

  19. Recurrent flow analysis in spatiotemporally chaotic 2-dimensional Kolmogorov flow

    E-Print Network [OSTI]

    Dan Lucas; Rich Kerswell

    2015-04-01T23:59:59.000Z

    Motivated by recent success in the dynamical systems approach to transitional flow, we study the efficiency and effectiveness of extracting simple invariant sets (recurrent flows) directly from chaotic/turbulent flows and the potential of these sets for providing predictions of certain statistics of the flow. Two-dimensional Kolmogorov flow (the 2D Navier-Stokes equations with a sinusoidal body force) is studied both over a square [0, 2{\\pi}]2 torus and a rectangular torus extended in the forcing direction. In the former case, an order of magnitude more recurrent flows are found than previously (Chandler & Kerswell 2013) and shown to give improved predictions for the dissipation and energy pdfs of the chaos via periodic orbit theory. Over the extended torus at low forcing amplitudes, some extracted states mimick the statistics of the spatially-localised chaos present surprisingly well recalling the striking finding of Kawahara & Kida (2001) in low-Reynolds-number plane Couette flow. At higher forcing amplitudes, however, success is limited highlighting the increased dimensionality of the chaos and the need for larger data sets. Algorithmic developments to improve the extraction procedure are discussed.

  20. Flow Rate Measurements Using Flow-Induced Pipe Vibration

    SciTech Connect (OSTI)

    R. P. Evans; Jonathan D. Blotter; Alan G. Stephens

    2004-03-01T23:59:59.000Z

    This paper focuses on the possibility of a non-intrusive, low cost, flow rate measurement technique. The technique is based on signal noise from an accelerometer attached to the surface of the pipe. The signal noise is defined as the standard deviation of the frequency averaged time series signal. Experimental results are presented that indicate a nearly quadratic relationship between the signal noise and mass flow rate in the pipe. It is also shown that the signal noise - flow rate relationship is dependant on the pipe material and diameter.

  1. US energy flow - 1984

    SciTech Connect (OSTI)

    Briggs, C.K.; Borg, I.Y.

    1985-07-01T23:59:59.000Z

    The 1984 energy flow diagram for the USA has been constructed using Department of Energy data. It is a convenient graphical device to show supply and demand as well as the size of end-use sectors. A 4% increase in overall energy consumption represented a reversal in a downward trend started in 1979. All indicators pointed to more healthy industrial and farm economies in 1984 than in the previous two years, which accounted for some part of the increase in energy use. While domestic crude oil production remained stable, oil imports rose eight percent also reversing a long-standing trend. Seventy-two million barrels of oil primarily from Mexico and the United Kingdom were added to the Strategic Petroleum Reserve bringing the total oil stored at year end to 451 million barrels. At the same time 49 million barrels of oil were produced from the government-owned Naval Petroleum Reserve No. 1 (Elk Hills, CA). Energy use in all end-use sectors grew in 1984 which is in keeping with increases in use of all types of fossil fuels as well as electricity. Increase in electrical power demand continued to exceed forecasts, and during 1984 contracts for imports to the northeast US were negotiated with Canada. Nuclear power contributed 15% of total power generated in the US. At year end there were 86 licensed reactors and 44 in either start-up or construction stages. Six were canceled or abandoned during construction during the year. 11 refs., 4 figs., 3 tabs.

  2. Ceramic Cross Flow Recuperator Design Parameters

    E-Print Network [OSTI]

    Gonzalez, J. M.; Rebello, W. J.

    1981-01-01T23:59:59.000Z

    the performance of the ceramic recuperator in various industrial furnaces. The ceramic cross flow recuperator core has multiple rectangular flow passages (perpendicular to each other) for the air and gas. Various flow passages are available contingent upon...

  3. Two phase flow in capillary tubes

    E-Print Network [OSTI]

    Suo, Mikio

    1963-01-01T23:59:59.000Z

    The flow of two phases, gas and liquid, has been studied in horizontal tubes of capillary diameter. The flow has been primarily studied in the regime where the gas flows as long bubbles separated from the wall of the tube ...

  4. Insertable fluid flow passage bridgepiece and method

    DOE Patents [OSTI]

    Jones, Daniel O. (Glenville, NV)

    2000-01-01T23:59:59.000Z

    A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.

  5. Flow distribution channels to control flow in process channels

    DOE Patents [OSTI]

    Tonkovich, Anna Lee; Arora, Ravi; Kilanowski, David

    2014-10-28T23:59:59.000Z

    The invention describes features that can be used to control flow to an array of microchannels. The invention also describes methods in which a process stream is distributed to plural microchannels.

  6. The transition from two phase bubble flow to slug flow

    E-Print Network [OSTI]

    Radovcich, Nick A.

    1962-01-01T23:59:59.000Z

    The process of transition from bubble to slug flow in a vertical pipe has been studied analytically and experimentally. An equation is presented which gives the agglomeration time as a function of void fraction, channel ...

  7. Thermocapillary Flow on Superhydrophobic Surfaces

    E-Print Network [OSTI]

    Baier, Tobias; Hardt, Steffen

    2010-01-01T23:59:59.000Z

    A liquid in Cassie-Baxter state above a structured superhydrophobic surface is ideally suited for surface driven transport due to its large free surface fraction in close contact to a solid. We investigate thermal Marangoni flow over a superhydrophobic array of fins oriented parallel or perpendicular to an applied temperature gradient. In the Stokes limit we derive an analytical expression for the bulk flow velocity above the surface and compare it with numerical solutions of the Navier-Stokes equation. Even for moderate temperature gradients comparatively large flow velocities are induced, suggesting to utilize this principle for microfluidic pumping.

  8. Exploring multi-layer flow network of international trade based on flow distances

    E-Print Network [OSTI]

    Shen, Bin; Zheng, Qiuhua

    2015-01-01T23:59:59.000Z

    Based on the approach of flow distances, the international trade flow system is studied from the perspective of multi-layer flow network. A model of multi-layer flow network is proposed for modelling and analyzing multiple types of flows in flow systems. Then, flow distances are introduced, and symmetric minimum flow distance is presented. Subsequently, we discuss the establishment of the multi-layer flow networks of international trade from two coupled viewpoints, i.e., the viewpoint of commodity flow and that of money flow. Thus, the multi-layer flow networks of international trade is explored. First, trading "trophic levels" are adopted to depict positions that economies occupied in the flow network. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodity, and there are some regularities between money flow network and commodity flow network. Second, we find that active and competitive countries trade a wide spectrum of products, while ...

  9. Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow...

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

    Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer, Longer-lasting Batteries Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer,...

  10. Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...

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

    Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using...

  11. Automation of radiochemical analysis by applying flow

    E-Print Network [OSTI]

    Sánchez, David

    of detection systems, including scintillation counting, a-spectrometers, proportional counters, mass spectrometry and spectrophotometry. ª 2010 Published by Elsevier Ltd. Keywords: Flow-analysis technique; Flow

  12. Minimum Stream Flow Standards (Connecticut)

    Broader source: Energy.gov [DOE]

    These regulations apply to all dams and structures which impound or divert waters on rivers or their tributaries, with some exceptions. The regulations set standards for minimum flow (listed in the...

  13. Nodes, modes and flow codes

    SciTech Connect (OSTI)

    Karniadakis, G.E.; Orszag, S.A. (Princeton Univ., NJ (United States))

    1993-03-01T23:59:59.000Z

    Computational fluid dynamics and the numerical prediction of fluid flow in the understanding and modeling of turbulence is discussed with emphasis on the development of direct numerical simulation (DNS) of high-Reynolds number turbulent flows. Recent advances in computer systems and their use in turbulence simulation are reviewed and the need for parallel processing to achieve teraflop speeds necessary for DNS is discussed. Computer system architectures, nodes, and parallel computers currently in use are reviewed. Spectral, spectral-element, particle, and hybrid difference methods of solving incompressible- and compressible-flow problems are examined. Four applications of parallel computers to turbulent flow problems are presented and future developments in computer systems are discussed. 24 refs.

  14. Miniaturized flow injection analysis system

    DOE Patents [OSTI]

    Folta, James A. (Livermore, CA)

    1997-01-01T23:59:59.000Z

    A chemical analysis technique known as flow injection analysis, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38.times.25.times.3 mm, but can be designed for gas analysis and be substantially smaller in construction.

  15. Message Flow Modulator Final Report

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    operational environment at the Patuxent River Naval Air Test Center with scenarios developed by an independent in testing and demonstrating the flow modulator at the Patuxent River Naval Air Test Center. #12; MESSAGE

  16. Capillary flows in flexible structures

    E-Print Network [OSTI]

    Hoberg, Theresa B. (Theresa Blinn)

    2013-01-01T23:59:59.000Z

    Interactions between capillary and elastic effects are relevant to a variety of applications, from micro- and nano-scale manufacturing to biological systems. In this thesis, we investigate capillary flows in extremely ...

  17. Mechanical design of flow batteries

    E-Print Network [OSTI]

    Hopkins, Brandon J. (Brandon James)

    2013-01-01T23:59:59.000Z

    The purpose of this research is to investigate the design of low-cost, high-efficiency flow batteries. Researchers are searching for next-generation battery materials, and this thesis presents a systems analysis encompassing ...

  18. 2007 Estimated International Energy Flows

    SciTech Connect (OSTI)

    Smith, C A; Belles, R D; Simon, A J

    2011-03-10T23:59:59.000Z

    An energy flow chart or 'atlas' for 136 countries has been constructed from data maintained by the International Energy Agency (IEA) and estimates of energy use patterns for the year 2007. Approximately 490 exajoules (460 quadrillion BTU) of primary energy are used in aggregate by these countries each year. While the basic structure of the energy system is consistent from country to country, patterns of resource use and consumption vary. Energy can be visualized as it flows from resources (i.e. coal, petroleum, natural gas) through transformations such as electricity generation to end uses (i.e. residential, commercial, industrial, transportation). These flow patterns are visualized in this atlas of 136 country-level energy flow charts.

  19. particle flow for nonlinear filters

    E-Print Network [OSTI]

    Dobigeon, Nicolas

    particle flow for nonlinear filters Fred Daum 19 June 2012 Copyright © 2012 Raytheon Company. All rights reserved. Customer Success Is Our Mission is a trademark of Raytheon Company. 1 #12;discrete time

  20. Multiscale modeling in granular flow

    E-Print Network [OSTI]

    Rycroft, Christopher Harley

    2007-01-01T23:59:59.000Z

    Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...

  1. Field Flows of Dark Energy

    E-Print Network [OSTI]

    Cahn, Robert N.

    2010-01-01T23:59:59.000Z

    Field Flows of Dark Energy Robert N. Cahn, Roland de Putter,July 8, 2008) Scalar ?eld dark energy evolving from a longthe key aspects of the dark energy evolution during much of

  2. Longitudinal dispersion in vegetated flow

    E-Print Network [OSTI]

    Murphy, Enda

    2006-01-01T23:59:59.000Z

    Vegetation is ubiquitous in rivers, estuaries and wetlands, strongly influencing both water conveyance and mass transport. The plant canopy affects both mean and turbulent flow structure, and thus both advection and ...

  3. Subcooled flow boiling of fluorocarbons

    E-Print Network [OSTI]

    Murphy, Richard Walter

    1971-01-01T23:59:59.000Z

    A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

  4. Comparative Study of f-Element Electronic Structure across a Series of Multimetallic Actinide, Lanthanide-Actinide and Lanthanum-Actinide Complexes Possessing Redox-Active Bridging Ligands

    SciTech Connect (OSTI)

    Schelter, Eric J.; Wu, Ruilian; Veauthier, Jacqueline M.; Bauer, Eric D.; Booth, Corwin H.; Thomson, Robert K.; Graves, Christopher R.; John, Kevin D.; Scott, Brian L.; Thompson, Joe D.; Morris, David E.; Kiplinger, Jaqueline L.

    2010-02-24T23:59:59.000Z

    A comparative examination of the electronic interactions across a series of trimetallic actinide and mixed lanthanide-actinide and lanthanum-actinide complexes is presented. Using reduced, radical terpyridyl ligands as conduits in a bridging framework to promote intramolecular metal-metal communication, studies containing structural, electrochemical, and X-ray absorption spectroscopy are presented for (C{sub 5}Me{sub 5}){sub 2}An[-N=C(Bn)(tpy-M{l_brace}C{sub 5}Me4R{r_brace}{sub 2})]{sub 2} (where An = Th{sup IV}, U{sup IV}; Bn = CH{sub 2}C{sub 6}H{sub 5}; M = La{sup III}, Sm{sup III}, Yb{sup III}, U{sup III}; R = H, Me, Et) to reveal effects dependent on the identities of the metal ions and R-groups. The electrochemical results show differences in redox energetics at the peripheral 'M' site between complexes and significant wave splitting of the metal- and ligand-based processes indicating substantial electronic interactions between multiple redox sites across the actinide-containing bridge. Most striking is the appearance of strong electronic coupling for the trimetallic Yb{sup III}-U{sup IV}-Yb{sup III}, Sm{sup III}-U{sup IV}-Sm{sup III}, and La{sup III}-U{sup IV}-La{sup III} complexes, [8]{sup -}, [9b]{sup -} and [10b]{sup -}, respectively, whose calculated comproportionation constant K{sub c} is slightly larger than that reported for the benchmark Creutz-Taube ion. X-ray absorption studies for monometallic metallocene complexes of U{sup III}, U{sup IV}, and U{sup V} reveal small but detectable energy differences in the 'white-line' feature of the uranium L{sub III}-edges consistent with these variations in nominal oxidation state. The sum of this data provides evidence of 5f/6d-orbital participation in bonding and electronic delocalization in these multimetallic f-element complexes. An improved, high-yielding synthesis of 4{prime}-cyano-2,2{prime}:6{prime},2{double_prime}-terpyridine is also reported.

  5. Synthesis, Structure Elucidation, and Redox Properties of [superscript 99]Tc Complexes of Lacunary Wells-Dawson Polyoxometalates: Insights into Molecular [superscript 99]Tc-Metal Oxide Interactions

    SciTech Connect (OSTI)

    McGregor, Donna; Burton-Pye, Benjamin P.; Howell, Robertha C.; Mbomekalle, Israel M.; Lukens, Jr., Wayne W.; Bian, Fang; Mausolf, Edward; Poineau, Frederic; Czerwinski, Kenneth R.; Francesconi, Lynn C. (UNLV); (City U/NY)

    2011-11-17T23:59:59.000Z

    The isotope {sup 99}Tc ({beta}{sub max}, 293.7; half-life, 2.1 x 10{sup 5} years) is an abundant product of uranium-235 fission in nuclear reactors and is present throughout the radioactive waste stored in underground tanks at the Hanford and Savannah River sites. Understanding and controlling the extensive redox chemistry of {sup 99}Tc is important in identifying tunable strategies to separate {sup 99}Tc from spent fuel and from waste tanks and, once separated, to identify and develop an appropriately stable waste form for {sup 99}Tc. Polyoxometalates (POMs), nanometer-sized models for metal oxide solid-state materials, are used in this study to provide a molecular level understanding of the speciation and redox chemistry of incorporated {sup 99}Tc. In this study, {sup 99}Tc complexes of the ({alpha}{sub 2}-P{sub 2}W{sub 17}O{sub 61}){sup 10-} and ({alpha}{sub 1}-P{sub 2}W{sub 17}O{sub 61}){sup 10-} isomers were prepared. Ethylene glycol was used as a 'transfer ligand' to minimize the formation of TcO{sub 2} {center_dot} xH{sub 2}O. The solution structures, formulations, and purity of TcVO({alpha}{sub 1}/{alpha}{sub 2}-P{sub 2}W{sub 17}O{sub 61}){sup 7-} were determined by multinuclear NMR. X-ray absorption spectroscopy of the complexes is in agreement with the formulation and structures determined from {sup 31}P and {sup 183}W NMR. Preliminary electrochemistry results are consistent with the EXAFS results, showing a facile reduction of the TcVO({alpha}{sub 1}-P{sub 2}W{sub 17}O{sub 61}){sup 7-} species compared to the TcVO({alpha}{sub 2}-P{sub 2}W{sub 17}O{sub 61}){sup 7-} analog. The {alpha}{sub 1} defect is unique in that a basic oxygen atom is positioned toward the {alpha}{sub 1} site, and the Tc{sup V}O center appears to form a dative metal-metal bond with a framework W site. These attributes may lead to the assistance of protonation events that facilitate reduction. Electrochemistry comparison shows that the ReV analogs are about 200 mV more difficult to reduce in accordance with periodic trends.

  6. Synthesis, structure elucidation and redox properties of 99Tc complexes of lacunary Wells Dawson polyoxometalates: insights into molecular 99Tc - metal oxide interactions

    SciTech Connect (OSTI)

    McGregor, Donna; Burton-Pye, Benjamin P.; Howell, Robertha C.; Mbomekalle, Israel M.; Lukens Jr, Wayne W.; Bian, Fang; Mausolf, Edward; Poineau, Frederic; Czerwinski, Kenneth R; Francesconi, Lynn C.

    2011-01-10T23:59:59.000Z

    The isotope 99Tc (beta max: 250 keV, half-life: 2 x 105 year) is an abundant product of uranium-235 fission in nuclear reactors and is present throughout the radioactive waste stored in underground tanks at Hanford and Savannah River. Understanding and controlling the extensive redox chemistry of 99Tc is important to identify tunable strategies to separate 99Tc from spent fuel and from waste tanks and once separated, to identify and develop an appropriately stable waste-form for 99Tc. Polyoxometalates (POMs), nanometer sized models for metal oxide solid-state materials, are used in this study to provide a molecular level understanding of the speciation and redox chemistry of incorporated 99Tc. In this study, 99Tc complexes of the (alpha 2-P2W17O61)10- and (alpha 1-P2W17O61)10- isomers were prepared. Ethylene glycol was used as a"transfer ligand" to minimize the formation of TcO2 cdot xH2O. The solution structures, formulations, and purity of TcVO(alpha 1/alpha 2-P2W17O61)7- were determined by multinuclear NMR. X-ray Absorption Spectroscopy of the complexes are in agreement with the formulation and structures determined from 31P and 183W NMR. Preliminary electrochemistry results are consistent with the EXAFS results, showing a facile reduction of the TcVO(alpha 1-P2W17O61)7- species compared to the TcVO(alpha 2-P2W17O61)7- analog. The alpha1- defect is unique in that a basic oxygen atom is positioned toward the alpha1- site and the TcVO center appears to form a dative metal-metal bond with a framework W site. These attributes may lead to the assistance of protonation events that facilitate reduction. Electrochemistry comparison shows that the ReV analogs are about 200 mV more difficult to reduce in accordance with periodic trends.

  7. Electrochemical characterization of surface-bound redox polymers derived from 1,1'-bis(((3-(triethoxysilyl)propyl)amino)carbonyl)cobaltocenium: charge transport, anion binding, and use in photoelectrochemical hydrogen generation

    SciTech Connect (OSTI)

    Simon, R.A.; Mallouk, T.E.; Daube, K.A.; Wrighton, M.S.

    1985-09-25T23:59:59.000Z

    This paper describes the behavior of electrode-bound redox material derived from the hydrolysis of the -Si(OEt)/sub 3/ groups of 1,1'-bis(((3-(triethoxysilyl)propyl)amino)carbonyl)cobaltocenium (I). Surfaces of the conventional electrodes SnO/sub 2/ and Pt derivatized with I have a reversible electrochemical response in H/sub 2/O/electrolyte; the E/sup 0/' is pH independent at -0.62 V vs. SCE. The photoelectrochemical behavior of p-type Si photocathodes derivatized with I reveals that the photoreduction of the cobaltocenium derivative can be effected at an electrode potential approx. 500 mV more positive than on metallic electrodes, consistent with the known behavior of p-type Si photocathodes. When polymer from I is deposited on p-type Si and subsequently coated with a small amount of Rh or Pd (approx. 10/sup -7/ mol/cm/sup 2/), the photoelectrochemical generation of H/sub 2/ is possible with 632.8-nm (approx. 15 mW/cm/sup 2/) radiation and efficiencies in the vicinity of 2%. The polymer derived from I is more optically transparent and more durable at negative potentials than redox polymers derived from vilogen monomers. Potential-step measurements and steady-state-current measurements for mediated redox processes show that the charge-transport rate for the polymer derived from I is about the same as for polymers from viologen monomers. 32 references, 8 figures.

  8. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    Flow Duration Curve Load Duration Curve 1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve What are they? How do you make one? Describes the percent of time a flow rate

  9. Stochastic models for turbulent reacting flows

    SciTech Connect (OSTI)

    Kerstein, A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    The goal of this program is to develop and apply stochastic models of various processes occurring within turbulent reacting flows in order to identify the fundamental mechanisms governing these flows, to support experimental studies of these flows, and to further the development of comprehensive turbulent reacting flow models.

  10. Mirrored serpentine flow channels for fuel cell

    DOE Patents [OSTI]

    Rock, Jeffrey Allan (Rochester, NY)

    2000-08-08T23:59:59.000Z

    A PEM fuel cell having serpentine flow field channels wherein the input/inlet legs of each channel border the input/inlet legs of the next adjacent channels in the same flow field, and the output/exit legs of each channel border the output/exit legs of the next adjacent channels in the same flow field. The serpentine fuel flow channels may be longer, and may contain more medial legs, than the serpentine oxidant flow channels.

  11. Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method

    E-Print Network [OSTI]

    Rheo-optical determination of flow birefringence and flow dichroism with the pulsed laser method online 29 August 2006 Rheo-optical measurements of the flow birefringence, flow dichroism systems under flow. However, the standard setup of an optical train, using phase modulation for the rheo-optical

  12. Connectivity due to preferential flow controls water flow and solute transport at the hillslope scale

    E-Print Network [OSTI]

    Weiler, Markus

    feedback, flow through the fractured bedrock, kinematic wave routing and flow through discrete preferentialConnectivity due to preferential flow controls water flow and solute transport at the hillslope the major controls on water flow and solute transport at the hillslope scale remains a major topic

  13. Cumulant expansions for atmospheric flows

    E-Print Network [OSTI]

    Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B

    2015-01-01T23:59:59.000Z

    The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...

  14. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, B.B.; Ballard, S.

    1994-08-23T23:59:59.000Z

    A monitoring probe for detecting groundwater migration is disclosed. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow. 4 figs.

  15. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, Brian B. (Aiken, SC); Ballard, Sanford (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A monitoring probe for detecting groundwater migration. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow.

  16. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; Bounds, J.A.; Rawool-Sullivan, M.W.

    1996-05-07T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors. 4 figs.

  17. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); Bounds, John A. (Los Alamos, NM); Rawool-Sullivan, Mohini W. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors.

  18. Non-Newtonian fluid flow

    E-Print Network [OSTI]

    Osinski, Charles Anthony

    1963-01-01T23:59:59.000Z

    zero and unity. The Ostwald- de Waele Equation (4), commonly known as the power law, is sometimes used to describe fluid behavior of this type. The rheological equation is (4) where the parameters "k" and "n" are constant for a particular fluid... be extended to include Reynolds numbers and the type of flow determined to be laminar and/or turbulent. It is assumed that the transition from laminar to turbulent flow occurs at a Reynolds number of 2100, the numeric distribution of Reynolds numbers...

  19. Nuclear reactor downcomer flow deflector

    DOE Patents [OSTI]

    Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

    2011-02-15T23:59:59.000Z

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  20. Interfacial flows in corrugated microchannels: flow regimes, transitions and hysteresis

    E-Print Network [OSTI]

    Feng, James J.

    , 1266-1276 (2011), doi:10.1016/j.ijmultiphaseflow.2011.08.003 #12;model, microfluidics, porous media 1 of displacing oil by water in enhanced oil recovery (Marle, 1981; Lenormand et al., 1988). More recently on hy- drodynamic principles and concrete flow mechanisms. In fact, conflicting assumptions have been

  1. The conformation change of model polymers in stochastic flow fields: Flow through fixed beds

    E-Print Network [OSTI]

    Shaqfeh, Eric

    The conformation change of model polymers in stochastic flow fields: Flow through fixed beds Alisa that as a polymer solution flows through a fixed bed, the pressure drop neces- sary to pump the solution may

  2. Superconducting flux flow digital circuits

    DOE Patents [OSTI]

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14T23:59:59.000Z

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  3. Neutrino Factory Mercury Flow Loop

    E-Print Network [OSTI]

    McDonald, Kirk

    ­ Could require double containment of mercury ­ Chase will certainly have a drain back into hot cell Decay 2010 #12;Hg Flow Overflow · Minimize pressure drops through piping Overflow Mercury Drain drops Gravity Drain Beam Dumptransitioning to 1 cm nozzle · Actual NF Hg inventory may reach SNS Gravity Drain

  4. Message Flow Modeling Oscar Nierstrasz

    E-Print Network [OSTI]

    Nierstrasz, Oscar

    Message Flow Modeling Oscar Nierstrasz and Dennis Tsichritzis Computer Systems Research Group University of Toronto ABSTRACT A message management system provides users with a facility for automatically handling messages. This paper describes a technique for characterizing the behaviour of such a system

  5. Collective flow in small systems

    E-Print Network [OSTI]

    Piotr Bozek; Wojciech Broniowski

    2014-07-24T23:59:59.000Z

    The large density of matter in the interaction region of the proton-nucleus or deuteron-nucleus collisions enables the collective expansion of the fireball. Predictions of the hydrodynamic model for the asymmetric transverse flow are presented and compared to experimental data.

  6. Stopping Cooling Flows with Jets

    E-Print Network [OSTI]

    Fabrizio Brighenti; William G. Mathews

    2006-01-24T23:59:59.000Z

    We describe 2D gasdynamical models of jets that carry mass as well as energy to the hot gas in galaxy clusters. These flows have many attractive attributes for solving the galaxy cluster cooling flow problem: Why the hot gas temperature and density profiles resemble cooling flows but show no spectral evidence of cooling to low temperatures. Using an approximate model for the cluster A1795, we show that mass-carrying jets can reduce the overall cooling rate to or below the low values implied by X-ray spectra. Biconical subrelativistic jets, described with several ad hoc parameters, are assumed to be activated when gas flows toward or cools near a central supermassive black hole. As the jets proceed out from the center they entrain more and more ambient gas. The jets lose internal pressure by expansion and are compressed by the ambient cluster gas, becoming rather difficult to observe. For a wide variety of initial jet parameters and several feedback scenarios the global cooling can be suppressed for many Gyrs while maintaining cluster temperature profiles similar to those observed. The intermittancy of the feedback generates multiple generations of X-ray cavities similar to those observed in the Perseus Cluster and elsewhere.

  7. Flow preconditioner for electrostatic precipitator

    SciTech Connect (OSTI)

    Honacker, H.; Drlik, R.J.

    1980-01-01T23:59:59.000Z

    A flow preconditioner for an electrostatic precipitator removes particulate matter from a stream of polluted gas immediately after it passes through a tangential inlet at the lower end of a vertical cylindrical housing and straightens and divides the stream into laminations parallel to the axis of the housing. It comprises an annular ledge or choke ring extending inwardly from said housing above the inlet and an assembly of vanes above said ledge extending radially from the axis of the housing and angularly spaced apart. Each of said vanes has a flow receiving edge directed toward said inlet, a curved portion extending upwardly and away from said inlet, and a flat portion extending upwardly from said curved portion in a plane parallel to the housing axis. The curved portion of each vane defines a trough having a camber which gradually decreases along its span from the outer end of the vane towards the axis of the housng, together with means to vary the centrifugal flow distribution relative to the housing to render the preconditioner adjustable for various flow capacities.

  8. Documenting Organizational Process Flow Modeling

    E-Print Network [OSTI]

    Schweik, Charles M.

    1 Documenting Organizational Processes or Process Flow Modeling Analysis Phase ­ Three Steps that describes (1) the current, and (2) the future structure of an organizational process ·"Natural language ­ An overview of an organizational system showing · system boundaries, · external entities that interact

  9. Flow assurance and multiphase pumping 

    E-Print Network [OSTI]

    Nikhar, Hemant G.

    2009-05-15T23:59:59.000Z

    -in-Pipe?????????????????????????????????????. 42 Non-Jacketed Insulation Systems?????????????????????????? 42 Syntactic Insulation?????????????????????????????????. 42 Heating?????????????????????????????????????????? 43 Pipeline Configurations for Heating????????????????????????? 45 Subsea... Various Chemicals Used in Oil and Gas Production Operations????????. 38 15 Seawater Temperature Gradients???????????????????????.. 43 16 Flow Model Schematic?????????????????????????????.. 44 17 Deliverability Affected by Cooling Effect of Pipeline...

  10. Comments on "Microscale flow visualization"

    E-Print Network [OSTI]

    A. Kwang-Hua Chu

    2005-10-22T23:59:59.000Z

    We make comments on the presentation of Sinton's paper (Microfluidics and Nanofluidics {\\bf 1}: 2, 2004) about the microscale flow visualization since the effects of the roughness along the microfabricated wall upon the current macroflow visualization methods could be significant and cannot be neglected in microdomain and even nanodomain.

  11. Rinse trough with improved flow

    DOE Patents [OSTI]

    O`Hern, T.J.; Grasser, T.W.

    1998-08-11T23:59:59.000Z

    Novel rinse troughs accomplish thorough uniform rinsing. The troughs are suitable for one or more essentially planar objects having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs provide uniform rinse fluid flow over the objects` surfaces to accomplish a more thorough rinse than prior art troughs. 5 figs.

  12. Liquid metal Flow Meter - Final Report

    SciTech Connect (OSTI)

    Andersen, C.; Hoogendoom, S.; Hudson, B.; Prince, J.; Teichert, K.; Wood, J.; Chase, K.

    2007-01-30T23:59:59.000Z

    Measuring the flow of liquid metal presents serious challenges. Current commercially-available flow meters use ultrasonic, electromagnetic, and other technologies to measure flow, but are inadequate for liquid metal flow measurement because of the high temperatures required by most liquid metals. As a result of the reactivity and high temperatures of most liquid metals, corrosion and leakage become very serious safety concerns. The purpose of this project is to develop a flow meter for Lockheed Martin that measures the flow rate of molten metal in a conduit.

  13. Structure of processes in flow reactor and closed reactor: Flow reactor

    E-Print Network [OSTI]

    Greifswald, Ernst-Moritz-Arndt-Universität

    Structure of processes in flow reactor and closed reactor: Flow reactor Closed reactor Active Zone -- chemical quasi- equilibria, similarity principles and macroscopic kinetics", in: Lectures on Plasma Physics

  14. Soluble Lead Flow Battery: Soluble Lead Flow Battery Technology

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    GRIDS Project: General Atomics is developing a flow battery technology based on chemistry similar to that used in the traditional lead-acid battery found in nearly every car on the road today. Flow batteries store energy in chemicals that are held in tanks outside the battery. When the energy is needed, the chemicals are pumped through the battery. Using the same basic chemistry as a traditional battery but storing its energy outside of the cell allows for the use of very low cost materials. The goal is to develop a system that is far more durable than today’s lead-acid batteries, can be scaled to deliver megawatts of power, and which lowers the cost of energy storage below $100 per kilowatt hour.

  15. Decentralized information flow control on a cluster

    E-Print Network [OSTI]

    Cliffer, Natan Tsvi Cohen

    2007-01-01T23:59:59.000Z

    Information flow control security models can prevent programs from divulging sensitive information in unexpected ways. There has been significant work on tracking information flow between processes in the same computer at ...

  16. Fluid Gravity Engineering Rocket motor flow analysis

    E-Print Network [OSTI]

    Anand, Mahesh

    Fluid Gravity Engineering Capability · Rocket motor flow analysis -Internal (performance) -External (plume / contamination) · Effect on landing site (surface alteration) -In-depth flow through porous young scientists/engineers Fluid Gravity Engineering Ltd #12;

  17. gtp_flow_power_estimator.xlsx

    Broader source: Energy.gov [DOE]

    This simple spreadsheet model estimates either the flow rate required to produce a specified level of power output, or the power output that can be produced from a specified flow rate.

  18. An optical investigation of air particle flows

    E-Print Network [OSTI]

    McCluskey, Denise R

    This thesis is a fundamental study of air-particle flow fields where the experimental parameters are characteristics of coal-fired electricity generating stations. The optical flow field measurement technique Particle Image Velocimetry (PIV...

  19. Numerical simulation of electrokinetically driven micro flows

    E-Print Network [OSTI]

    Hahm, Jungyoon

    2005-11-01T23:59:59.000Z

    in a micro-channel is studied. External electric field, flow rate of pressure driven flow, and geometry in the micro-channel are manipulated to obtain the focusing point, which led to determination of the electrophoretic mobility and (relative...

  20. Anisotropic collective flow of a Lorentz gas

    E-Print Network [OSTI]

    Nicolas Borghini; Clement Gombeaud

    2011-06-30T23:59:59.000Z

    Analytical results for the anisotropic collective flow of a Lorentz gas of massless particles scattering on fixed centres are presented.

  1. Building up the elliptic flow: analytical insights

    E-Print Network [OSTI]

    Yoshitaka Hatta; Bo-Wen Xiao

    2014-07-15T23:59:59.000Z

    In this paper, we present a fully analytical description of the early-stage formation of elliptic flow in relativistic viscous hydrodynamics. We first construct an elliptic deformation of Gubser flow which is a boost invariant solution of the Navier-Stokes equation with a nontrivial transverse profile. We then analytically calculate the momentum anisotropy of the flow as a function of time and discuss the connection with the empirical formula by Bhalerao {\\it et al.} regarding the viscosity dependence of elliptic flow.

  2. Geothermal Heat Flow and Existing Geothermal Plants | Department...

    Energy Savers [EERE]

    Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Plants With plants in development. Click...

  3. annular vertical flow: Topics by E-print Network

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

    of the polymer solution only. The linear stability analysis of the flow in the short-wave approximation captures quantitatively the flow diagram. Surprisingly, unstable flows...

  4. Effects of flow cell design on charge percolation and storage...

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

    Electrochemical flow capacitor Energy storage Flow battery Flowable electrode Supercapacitor a b s t r a c t The electrochemical flow capacitor (EFC) is an electrical energy...

  5. Zonal Flow as Pattern Formation

    E-Print Network [OSTI]

    Parker, Jeffrey B

    2015-01-01T23:59:59.000Z

    In this section, we examine the transition from statistically homogeneous turbulence to inhomogeneous turbulence with zonal flows. Statistical equations of motion can be derived from the quasilinear approximation to the Hasegawa-Mima equation. We review recent work that finds a bifurcation of these equations and shows that the emergence of zonal flows mathematically follows a standard type of pattern formation. We also show that the dispersion relation of modulational instability can be extracted from the statistical equations of motion in a certain limit. The statistical formulation can thus be thought to offer a more general perspective on growth of coherent structures, namely through instability of a full turbulent spectrum. Finally, we offer a physical perspective on the growth of large-scale structures.

  6. Supercritical flow in rectangular expansions

    E-Print Network [OSTI]

    Walsh, Peter.

    1968-01-01T23:59:59.000Z

    is the differential element of length along C. Equations [7] and [8] may be rearranged in the following manner: du = ? dx + ? dy du Qu gx ay dv = ? dx + ? dy 3v av 'bx Py [10] where du = (3u/Bs)ds, dv = (pv/3s)ds, dx = (3x/as)ds, and dy = (s y/p s) ds. The four... common tangent A P . Since a disturbance travels from A to P in n 1 the same time that a particle moves from A to A it follows that n A P = sin S =? A A v 1 n where I9 is the angle between the shock wave and the direction of flow. When the flow...

  7. Characterizing flow fluctuations with moments

    E-Print Network [OSTI]

    Rajeev S. Bhalerao; Jean-Yves Ollitrault; Subrata Pal

    2015-01-22T23:59:59.000Z

    We present a complete set of multiparticle correlation observables for ultrarelativistic heavy-ion collisions. These include moments of the distribution of the anisotropic flow in a single harmonic, and also mixed moments, which contain the information on correlations between event planes of different harmonics. We explain how all these moments can be measured using just two symmetric subevents separated by a rapidity gap. This presents a multi-pronged probe of the physics of flow fluctuations. For instance, it allows to test the hypothesis that event-plane correlations are generated by non-linear hydrodynamic response. We illustrate the method with simulations of events in A MultiPhase Transport (AMPT) model.

  8. Gas flow in barred potentials

    E-Print Network [OSTI]

    Sormani, Mattia C; Magorrian, John

    2015-01-01T23:59:59.000Z

    We use a Cartesian grid to simulate the flow of gas in a barred Galactic potential and investigate the effects of varying the sound speed in the gas and the resolution of the grid. For all sound speeds and resolutions, streamlines closely follow closed orbits at large and small radii. At intermediate radii shocks arise and the streamlines shift between two families of closed orbits. The point at which the shocks appear and the streamlines shift between orbit families depends strongly on sound speed and resolution. For sufficiently large values of these two parameters, the transfer happens at the cusped orbit as hypothesised by Binney et al. over two decades ago. For sufficiently high resolutions the flow downstream of the shocks becomes unsteady. If this unsteadiness is physical, as appears to be the case, it provides a promising explanation for the asymmetry in the observed distribution of CO.

  9. General Message Flow Modulator Ann E. Siebert

    E-Print Network [OSTI]

    Boyer, Robert Stephen

    General Message Flow Modulator Ann E. Siebert Donald I. Good Technical Report #42 March 1984 (512) 471-1901 #12;Abstract The general message flow modulator is a high level design of a family of mechanisms for controlling the flow of messages from a source to a destination. This family of mechanisms has

  10. Flow and Plate Motion in Compressor Valves

    E-Print Network [OSTI]

    Twente, Universiteit

    Flow and Plate Motion in Compressor Valves #12;Flow and Plate Motion in Compressor Valves R.A. Habing Cover Image: 4-stage reciprocating compressor system, Courtesy of Ariel Corporation Thesis.A. Habing, Enschede, The Netherlands #12;FLOW AND PLATE MOTION IN COMPRESSOR VALVES PROEFSCHRIFT ter

  11. Secured Information Flow for Asynchronous Sequential Processes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Secured Information Flow for Asynchronous Sequential Processes Isabelle Attali, Denis Caromel for unauthorized information flows. As a final result, all authorized communication paths are secure: no disclosure a new issue in data confidentiality: authorization of secured information flow transiting (by the mean

  12. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    #12;Flow Duration Curve Load Duration Curve #12;1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve #12;What are they? How do you make one? #12;Describes

  13. Optimal Power Flow Incorporating Voltage Collapse Constraints

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    Optimal Power Flow Incorporating Voltage Collapse Constraints William Rosehart Claudio Ca on the current operating con- ditions is presented. Second, an Optimal Power Flow formulation that incorporates: Voltage Collapse, Optimal Power Flow, Bifur- cations. I. Introduction As open-access market principles

  14. (Preview Draft) Chapter 3. Stocks and Flows

    E-Print Network [OSTI]

    Ford, Andrew

    the state over time. It will take some time for the flows to have their effect on the stocks, so the stocks(Preview Draft) Chapter 3. Stocks and Flows: The Building Blocks of System Dynamics Models The best way to construct a model is to start with the stocks, add the flows and then use converters to explain

  15. Automatic Control Flow Generation from Software Architectures

    E-Print Network [OSTI]

    Lau, Kung-Kiu

    -time automatically. To achieve this we take a different approach to system construction. We take control out.-K. Lau and V. Ukis generic connectors, and generate control flow of the system automatically at run in different systems with different control flows. Our automatic runtime control flow generation not only

  16. Laser cross-flow gas system

    DOE Patents [OSTI]

    Duncan, D.B.

    1992-11-24T23:59:59.000Z

    A method and laser apparatus are disclosed which provide for a cross-flow of gas near one end of a laser discharge tube. The cross-flow of gas causes a concentration gradient which affects diffusion of contaminants in the discharge tube towards the cross-flow of the gas, which contaminants are then withdrawn from the discharge tube. 1 figure.

  17. SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW

    E-Print Network [OSTI]

    Santos, Juan

    SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW J. E. Santos1, G. B. Savioli2, J. M. Carcione3, D´e, Argentina SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12;Introduction. I Storage of CO2). SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12;Introduction. II CO2 is separated from natural

  18. and wall bounded shear flows

    E-Print Network [OSTI]

    Hoepffner, Jérôme

    60 0 10 20 30 40 50 60 0 0.5 1 1.5 2 Model parameters r1 r2 #12;Optimisation : the Lagrange · Covariance and energy · Disturbances · Optimization · Time varying gains · Steady state kernels #12;Flow(f)H Energy E[E(q(t))] = Tr(E[q(t)q(t) ] #12;Linear filtering Propagation of the estimation error ~q ~q = (A

  19. Countercurrent flow absorber and desorber

    DOE Patents [OSTI]

    Wilkinson, William H. (Columbus, OH)

    1984-01-01T23:59:59.000Z

    Countercurrent flow absorber and desorber devices are provided for use in absorption cycle refrigeration systems and thermal boosting systems. The devices have increased residence time and surface area resulting in improved heat and mass transfer characteristics. The apparatuses may be incorporated into open cycle thermal boosting systems in which steam serves both as the refrigerant vapor which is supplied to the absorber section and as the supply of heat to drive the desorber section of the system.

  20. Countercurrent flow absorber and desorber

    DOE Patents [OSTI]

    Wilkinson, W.H.

    1984-10-16T23:59:59.000Z

    Countercurrent flow absorber and desorber devices are provided for use in absorption cycle refrigeration systems and thermal boosting systems. The devices have increased residence time and surface area resulting in improved heat and mass transfer characteristics. The apparatuses may be incorporated into open cycle thermal boosting systems in which steam serves both as the refrigerant vapor which is supplied to the absorber section and as the supply of heat to drive the desorber section of the system. 9 figs.

  1. Microgravity Flow Regime Transition Modeling

    E-Print Network [OSTI]

    Shephard, Adam M.

    2010-07-14T23:59:59.000Z

    by Ghrist (2008) where an existing computer code, RELAP 5-3D, demonstrated the limitations of currently available computational modeling when applied to zero-g conditions. 1.2.2 EXPERIMENTAL APPARATUS All flow regime mapping experiments consist of a... ............................................................... 9 2.3 Dukler et al. 1988/Janicot 1988 ............................................. 9 2.4 Colin et al. 1991 .................................................................... 11 2.5 Huckerby and Rezkallah 1992...

  2. Cyclotron resonance in plasma flow

    SciTech Connect (OSTI)

    Artemyev, A. V.; Agapitov, O. V.; Krasnoselskikh, V. V. [LPC2E/CNRS-University of Orleans, Orleans (France)] [LPC2E/CNRS-University of Orleans, Orleans (France)

    2013-12-15T23:59:59.000Z

    This paper is devoted to the mechanism of particle acceleration via resonant interaction with the electromagnetic circular wave propagating along the inhomogeneous background magnetic field in the presence of a plasma flow. We consider the system where the plasma flow velocity is large enough to change the direction of wave propagation in the rest frame. This system mimics a magnetic field configuration typical for inner structure of a quasi-parallel shock wave. We consider conditions of gyroresonant interaction when the force corresponding to an inhomogeneity of the background magnetic field is compensated by the Lorentz force of the wave-magnetic field. The wave-amplitude is assumed to be about 10% of the background magnetic field. We show that particles can gain energy if kv{sub sw}>?>kv{sub sw}??{sub c} where k is the wave number, v{sub sw} is a plasma flow velocity, and ? and ?{sub c} are the wave frequency and the particle gyrofrequency, respectively. This mechanism of acceleration resembles the gyrosurfing mechanism, but the effect of the electrostatic field is replaced by the effect of the magnetic field inhomogeneity.

  3. Structural stability of cooling flows

    E-Print Network [OSTI]

    Henrik Omma; James Binney

    2003-12-31T23:59:59.000Z

    Three-dimensional hydrodynamical simulations are used to investigate the structural stability of cooling flows that are episodically heated by jets from a central AGN. The radial profile of energy deposition is controlled by (a) the power of the jets, and (b) the pre-outburst density profile. A delay in the ignition of the jets causes more powerful jets to impact on a more centrally concentrated medium. The net effect is a sufficient increase in the central concentration of energy deposition to cause the post-outburst density profile to be less centrally concentrated than that of an identical cluster in which the outburst happened earlier and was weaker. These results suggest that the density profiles of cooling flows oscillate around an attracting profile, thus explaining why cooling flows are observed to have similar density profiles. The possibility is raised that powerful FR II systems are ones in which this feedback mechanism has broken down and a runaway growth of the source parameters has occurred.

  4. Cobalt-iron red-ox behavior in nanostructured La{sub 0.4}Sr{sub 0.6}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} cathodes

    SciTech Connect (OSTI)

    Soldati, Analia L., E-mail: asoldati@cab.cnea.gov.ar [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina); Baque, Laura, E-mail: baque.laura@gmail.com [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina)] [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina); Napolitano, Federico, E-mail: napolitf@ib.cab.cnea.gov.ar [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina)] [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina); Serquis, Adriana, E-mail: aserquis@cab.cnea.gov.ar [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina)] [CONICET-CNEA Departamento de Caracterizacion de Materiales, Centro Atomico Bariloche, Av. Bustillo 9500, S.C. de Bariloche R8402AGP, Rio Negro (Argentina)

    2013-02-15T23:59:59.000Z

    Nano-sized La{sub 0.4}Sr{sub 0.6}Co{sub 0.8}Fe{sub 0.2}O{sub 3-{delta}} (LSCF) perovskite samples (prepared by a conventional acetate route and a novel acetate synthesis with HMTA additives), were tested simulating a red-ox cycle. The crystallography was studied by X-ray Powder Diffraction (XPD) and the changes in the oxidation state of the perovskite B-site were evaluated by synchrotron X-ray Absorption Near Edge Spectroscopy (XANES). After a reducing treatment, LSFC particles show the appearance of a new phase that coexists with the original one. The structural change is accompanied by a Co and Fe formal oxidation states decrease, although Fe remains always closer to 4+ and Co closer to 3+. The treatment produces a B-site valence average reduction from 3.52+ to 3.26+ and the formation of oxygen vacancies. A re-oxidation treatment under O{sub 2} rich atmosphere at 800 Degree-Sign C for 10 h shows that the change is reversible and independent of the two chemical methods used to synthesize the LSCF nano-particles. - Graphical abstract: XANES and XPD measurements in nanostructured LSCF before (black) and after (red/green) a red/ox cycle. Highlights: Black-Right-Pointing-Pointer Red-ox treatments in LSCF nano-particles cause a reversible reaction. Black-Right-Pointing-Pointer XPD analyses show that a new 'reduced' phase coexist with the oxidize one. Black-Right-Pointing-Pointer The B-site formal oxidation state decreases and the {delta} increases upon reduction. Black-Right-Pointing-Pointer Fe remains in a higher valence (closer to 4+) than Co (close to 3+). Black-Right-Pointing-Pointer The behavior seems to be independent of the synthesis method used.

  5. Optic Flow Sensor Objective: Using optic flow sensors, detect and track

    E-Print Network [OSTI]

    Wirthlin, Michael J.

    Optic Flow Sensor Objective: Using optic flow sensors, detect and track the walls of a rural or urban terrain. Principle Investigators: Tim McLain, Randy Beard Optic Flow Sensor · Computationally factor ­ 1" x 1" x 1.5" · Inexpensive ­ $80 including optics · Fast ­ computes optic flow at 2300 fps2006

  6. Self-regulating flow control device

    DOE Patents [OSTI]

    Humphreys, Duane A. (Pittsburgh, PA)

    1984-01-01T23:59:59.000Z

    A variable, self-regulating valve having a hydraulic loss coefficient proportional to a positive exponential power of the flow rate. The device includes two objects in a flow channel and structure which assures that the distance between the two objects is an increasing function of the flow rate. The range of spacing between the objects is such that the hydraulic resistance of the valve is an increasing function of the distance between the two objects so that the desired hydraulic loss coefficient as a function of flow rate is obtained without variation in the flow area.

  7. Vinyasa Flow Awaken your inner warrior! This dynamic flow infuses

    E-Print Network [OSTI]

    -1pm Informal Recreation Open Gym Basketball-6/17-8/14 Gym 147 Monday's and Wednesdays: 12-1pm #12;.sfsu.edu/~recsport Gentle Hatha Yoga 12-1pm (BH6) -Jacalyn Dance-Begins 6/17 12-1pm (Gym 100J) -Mo PIYO® 12-1pm (Gym 149) -Adair 6/10-7/23 Vinyasa Flow 12-1pm (BH6) -Jeff ZUMBA®-Begins 6/18 12-1pm (Gym 100) -Erika- XL Strength

  8. Controlling the Delay of Small Flows in Datacenters

    E-Print Network [OSTI]

    Carra, Damiano

    and CAPEX and ignore designs which could help reduce delay of delay sensitive flows. The flow routing

  9. Potential Flow Calculations of Axisymmetric Ducted Wind Turbines

    E-Print Network [OSTI]

    Widnall, Sheila

    2009-09-02T23:59:59.000Z

    An incompressible potential-flow vortex method has been constructed to analyze the flow field of a ducted

  10. A new precision flow calorimeter

    E-Print Network [OSTI]

    Johnson, Mark Gezer

    1984-01-01T23:59:59.000Z

    . THE REFERENCE FLUID CIRCUIT (The Thermo-Syphon System) 2. THE SAMPLE FLUID CIRCUIT 11 17 CALORIMETER AUXILIARY EQUIPMENT 1. BAYONET SYSTEM 2. MATCHING HEATER 3. PRESSURE TRANSDUCER 4. VACUUM SYSTEM 5. MAGNETIC STIRRER 6. METERING PUMP 20 25 25 31... Circuit (Thermo-Syphon System) Detail 12 4 A Typical Cycle of Thermo-Syphon System on a PT Diagram of Freon&-11 13 5 The Reference Fluid Circuit Simplified 14 6 The Sample Fluid Flow System 7 Calorimeter Detail 21 8 Bayonet System Detail 9 Copper...

  11. Jet quenching and elliptic flow

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2007-08-29T23:59:59.000Z

    In jet quenching, a hard QCD parton, before fragmenting into a jet of hadrons, deposits a fraction of its energy in the medium, leading to suppressed production of high-$p_T$ hadrons. Assuming that the deposited energy quickly thermalizes, we simulate the subsequent hydrodynamic evolution of the QGP fluid. Explicit simulation of Au+Au collision with and without a quenching jet indicate that elliptic flow is greatly reduced in a jet event. The result can be used to identify the jet events in heavy ion collisions.

  12. Flow Phenomena at AGS Energies

    E-Print Network [OSTI]

    J. P. Wessels

    1997-04-07T23:59:59.000Z

    In this talk some of the latest data on directed sideward, elliptic, radial, and longitudinal flow at AGS energies will be reviewed. A method to identify the reaction plane event by event and the measurement of its resolution will be discussed. The distributions of global observables (transverse energy E_T and charged particle multiplicity N_c), as well as those of identified particles will be shown. Finally, the data will be put in context with measurements at other beam energies. These systematics will then be discussed in terms of possible signatures of the QCD phase transition.

  13. Zonal flow dynamics in the double tearing mode with antisymmetric shear flows

    SciTech Connect (OSTI)

    Mao, Aohua [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Graduate School of Energy Science, Kyoto University, Uji, Kyoto 6110011 (Japan); Li, Jiquan, E-mail: lijq@energy.kyoto-u.ac.jp [Graduate School of Energy Science, Kyoto University, Uji, Kyoto 6110011 (Japan)] [Graduate School of Energy Science, Kyoto University, Uji, Kyoto 6110011 (Japan); Liu, Jinyuan, E-mail: jyliu@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Kishimoto, Yasuaki [Graduate School of Energy Science, Kyoto University, Uji, Kyoto 6110011 (Japan) [Graduate School of Energy Science, Kyoto University, Uji, Kyoto 6110011 (Japan); Institude of Advanced Energy, Kyoto University, Uji, Kyoto 6110011 (Japan)

    2014-05-15T23:59:59.000Z

    The generation dynamics and the structural characteristics of zonal flows are investigated in the double tearing mode (DTM) with antisymmetric shear flows. Two kinds of zonal flow oscillations are revealed based on reduced resistive magnetohydrodynamics simulations, which depend on the shear flow amplitudes corresponding to different DTM eigen mode states, elaborated by Mao et al. [Phys. Plasmas 20, 022114 (2013)]. For the weak shear flows below an amplitude threshold, v{sub c}, at which two DTM eigen states with antisymmetric or symmetric magnetic island structure are degenerated, the zonal flows grow oscillatorily in the Rutherford regime during the nonlinear evolution of the DTMs. It is identified that the oscillation mechanism results from the nonlinear interaction between the distorted islands and the zonal flows through the modification of shear flows. However, for the medium shear flows above v{sub c} but below the critical threshold of the Kelvin-Helmholtz instability, an oscillatory growing zonal flow occurs in the linear phase of the DTM evolution. It is demonstrated that the zonal flow oscillation originates from the three-wave mode coupling or a modulation instability pumped by two DTM eigen modes with the same frequency but opposite propagating direction. With the shear flows increasing, the amplitude of zonal flow oscillation increases first and then decreases, whilst the oscillation frequency as twice of the Doppler frequency shift increases. Furthermore, impacts of the oscillatory zonal flows on the nonlinear evolution of DTM islands and the global reconnection are also discussed briefly.

  14. A constitutive law for dense granular flows

    E-Print Network [OSTI]

    Pierre Jop; Yoël Forterre; Olivier Pouliquen

    2006-12-05T23:59:59.000Z

    A continuum description of granular flows would be of considerable help in predicting natural geophysical hazards or in designing industrial processes. However, the constitutive equations for dry granular flows, which govern how the material moves under shear, are still a matter of debate. One difficulty is that grains can behave like a solid (in a sand pile), a liquid (when poured from a silo) or a gas (when strongly agitated). For the two extreme regimes, constitutive equations have been proposed based on kinetic theory for collisional rapid flows, and soil mechanics for slow plastic flows. However, the intermediate dense regime, where the granular material flows like a liquid, still lacks a unified view and has motivated many studies over the past decade. The main characteristics of granular liquids are: a yield criterion (a critical shear stress below which flow is not possible) and a complex dependence on shear rate when flowing. In this sense, granular matter shares similarities with classical visco-plastic fluids such as Bingham fluids. Here we propose a new constitutive relation for dense granular flows, inspired by this analogy and recent numerical and experimental work. We then test our three-dimensional (3D) model through experiments on granular flows on a pile between rough sidewalls, in which a complex 3D flow pattern develops. We show that, without any fitting parameter, the model gives quantitative predictions for the flow shape and velocity profiles. Our results support the idea that a simple visco-plastic approach can quantitatively capture granular flow properties, and could serve as a basic tool for modelling more complex flows in geophysical or industrial applications.

  15. Flow of suspensions in pipelines

    SciTech Connect (OSTI)

    Nasr-El-Din, H.A. [Laboratory R& D Center, Saudi Aramco, Dhahran (Saudi Arabia)

    1996-12-31T23:59:59.000Z

    Slurry pipelines are used in many industrial applications. Several parameters are often needed by the operator, including critical deposit velocity, solids concentration, and particle velocity profiles. This chapter first reviews important formulas used to predict critical deposit velocity both in Newtonian and non-Newtonian (power-law) carrier fluids. Various methods to measure local velocity and solids concentration profiles in slurry pipelines are discussed. Local solids concentration can be measured by sample withdrawal technique. However, the sample should be withdrawn at isokinetic conditions. Sampling downstream of tees and elbows can result in significant errors in measuring solids concentration. Gamma-ray absorption methods can be used; however, two scans are needed to obtain local solids concentration. Bulk velocity of conductive slurries can be obtained using magnetic flow meters mounted on a vertical section of the pipe. Local particle velocity can be obtained using conductivity probes. NMR methods can be used to measure concentration and particle velocity profiles but are limited to small-diameter pipes. Vertical solids concentration of coarse slurries flowing in a horizontal pipeline exhibits a positive gradient near the bottom of the pipe. Traditional models to predict these profiles are given, and new mathematical models and computer software to determine these profiles are introduced. 104 refs., 31 figs., 1 tab.

  16. Process for retarding fluid flow

    SciTech Connect (OSTI)

    Sandford, B.B.; Zillmer, R.C.

    1989-01-10T23:59:59.000Z

    A process is described for retarding the flow of fluid in a subterranean formation, comprising: (a) introducing an effective amount of a gel-forming composition into a subterranean formation, the gel-forming composition being operable when gelled in the formation for retarding the flow of fluid therein. The gel-forming composition consists of: i. a first substance dissolved in water to form an aqueous solution, the first substance being selected from the group consisting of polyvivyl alcohols, and mixtures thereof, wherein the gel-forming composition contains an amount of the first substance of from about 0.5 to about 5 weight percent of the gel-forming composition, and ii. an effective amount of glutaraldehyde which is operable for forming a weakly acidic condition having a pH from about 5.5 to less than 7 in the gel-forming composition and also operable for promoting crosslinking of the first substance and glutaraldehyde and for forming a gel from the gel-forming composition under the weakly acidic condition within a period of time no greater than about 5 days without adding an acidic catalyst to the gel-forming composition to lower the pH of the gel-forming composition below about 5.5.

  17. CFD analysis of laminar oscillating flows

    SciTech Connect (OSTI)

    Booten, C. W. Charles W.); Konecni, S. (Snezana); Smith, B. L. (Barton L.); Martin, R. A. (Richard A.)

    2001-01-01T23:59:59.000Z

    This paper describes a numerical simulations of oscillating flow in a constricted duct and compares the results with experimental and theoretical data. The numerical simulations were performed using the computational fluid dynamics (CFD) code CFX4.2. The numerical model simulates an experimental oscillating flow facility that was designed to test the properties and characteristics of oscillating flow in tapered ducts, also known as jet pumps. Jet pumps are useful devices in thermoacoustic machinery because they produce a secondary pressure that can counteract an unwanted effect called streaming, and significantly enhance engine efficiency. The simulations revealed that CFX could accurately model velocity, shear stress and pressure variations in laminar oscillating flow. The numerical results were compared to experimental data and theoretical predictions with varying success. The least accurate numerical results were obtained when laminar flow approached transition to turbulent flow.

  18. Multicommodity Flows and Cuts in Polymatroidal Networks

    E-Print Network [OSTI]

    Chekuri, Chandra; Raja, Adnan; Viswanath, Pramod

    2011-01-01T23:59:59.000Z

    We consider multicommodity flow and cut problems in {\\em polymatroidal} networks where there are submodular capacity constraints on the edges incident to a node. Polymatroidal networks were introduced by Lawler and Martel and Hassin in the single-commodity setting and are closely related to the submodular flow model of Edmonds and Giles; the well-known maxflow-mincut theorem holds in this more general setting. Polymatroidal networks for the multicommodity case have not, as far as the authors are aware, been previously explored. Our work is primarily motivated by applications to information flow in wireless networks. We also consider the notion of undirected polymatroidal networks and observe that they provide a natural way to generalize flows and cuts in edge and node capacitated undirected networks. We establish poly-logarithmic flow-cut gap results in several scenarios that have been previously considered in the standard network flow models where capacities are on the edges or nodes. Our results have alread...

  19. Gradual Variation Analysis for Groundwater Flow

    E-Print Network [OSTI]

    Chen, Li

    2010-01-01T23:59:59.000Z

    Groundwater flow in Washington DC greatly influences the surface water quality in urban areas. The current methods of flow estimation, based on Darcy's Law and the groundwater flow equation, can be described by the diffusion equation (the transient flow) and the Laplace equation (the steady-state flow). The Laplace equation is a simplification of the diffusion equation under the condition that the aquifer has a recharging boundary. The practical way of calculation is to use numerical methods to solve these equations. The most popular system is called MODFLOW, which was developed by USGS. MODFLOW is based on the finite-difference method in rectangular Cartesian coordinates. MODFLOW can be viewed as a "quasi 3D" simulation since it only deals with the vertical average (no z-direction derivative). Flow calculations between the 2D horizontal layers use the concept of leakage. In this project, we have established a mathematical model based on gradually varied functions for groundwater data volume reconstruction. T...

  20. Flow characteristics in underground coal gasification

    SciTech Connect (OSTI)

    Chang, H.L.; Himmelblau, D.M.; Edgar, T.F.

    1982-01-01T23:59:59.000Z

    During the Hoe Creek No. 2 (Wyoming) underground-coal-gasification field test, researchers introduced helium pulses to characterize the flow field and to estimate the coefficients in dispersion models of the flow. Flow models such as the axial-dispersion and parallel tanks-in-series models allowed interpretation of the in situ combustion flow field from the residence time distribution of the tracer gas. A quantitative analysis of the Hoe Creek tracer response curves revealed an increasing departure from a plug-flow regime with time, which was due to the combined effects of the free and forced convection in addition to the complex nonuniformity of the flow field. The Peclet number was a function of temperature, pressure, gas recovery, and characteristic velocity, as well as the split of the gas between the parallel streams in the model.

  1. A theory for radial jet reattachment flow

    E-Print Network [OSTI]

    Hadden, Lynne Loise

    1987-01-01T23:59:59.000Z

    to be dependent on nozzle exit radius, nozzle exit direction, reattachment plate distance, and Reynold's number of the exit flow. TO MY MOTHER AND DAD AND CLOSE FRIENDS WHO PROVIDED LOVING SUPPORT ACKNOWLEDGMENT This research has been partially supported... Discretization of Flow Variables and Program Implementation. 21 4. RESULTS AND DISCUSSION. 24 4. 1 Effect of Varying Distance of Reattachment Plate from the Nozzle Exit. 24 4. 2 Effect of Changing Nozzle Exit Flow Direction. 46 4. 3 Effect of Changing...

  2. Lanthanides as particulate flow markers in ruminants

    E-Print Network [OSTI]

    Conner, Michael Cronan

    1977-01-01T23:59:59.000Z

    Suhj ect: Anindl I'lutri tion LANTHANIDES AS PARTICULATE FLOW NARVERS IN RUNINANTS A Thesis by MICUAEL CRONAN CONNER Approved as to style and content by: Yie, aber+ (Yieniber) August l977 ABSTPACT Lanthanides as Particulate Flow Markers... in Ruminants (Auoust 1977) Michael Cronan Conner, B. S. , California Polytechnic State University at San Luis Gbispo Chairman of Advisory Committee: Gr. Ii. C, Ellis The validity of lanthanides as par+iculate flow markers was evaluated by comparing...

  3. Microsphere estimates of blood flow: Methodological considerations

    SciTech Connect (OSTI)

    von Ritter, C.; Hinder, R.A.; Womack, W.; Bauerfeind, P.; Fimmel, C.J.; Kvietys, P.R.; Granger, D.N.; Blum, A.L. (Univ. of the Witwatersrand, Johannesburg (South Africa) Louisianna State Univ. Medical Center, Shreveport (USA) Universitaire Vaudois (Switzerland))

    1988-02-01T23:59:59.000Z

    The microsphere technique is a standard method for measuring blood flow in experimental animals. Sporadic reports have appeared outlining the limitations of this method. In this study the authors have systematically assessed the effect of blood withdrawals for reference sampling, microsphere numbers, and anesthesia on blood flow estimates using radioactive microspheres in dogs. Experiments were performed on 18 conscious and 12 anesthetized dogs. Four blood flow estimates were performed over 120 min using 1 {times} 10{sup 6} microspheres each time. The effects of excessive numbers of microspheres pentobarbital sodium anesthesia, and replacement of volume loss for reference samples with dextran 70 were assessed. In both conscious and anesthetized dogs a progressive decrease in gastric mucosal blood flow and cardiac output was observed over 120 min. This was also observed in the pancreas in conscious dogs. The major factor responsible for these changes was the volume loss due to the reference sample withdrawals. Replacement of the withdrawn blood with dextran 70 led to stable blood flows to all organs. The injection of excessive numbers of microspheres did not modify hemodynamics to a greater extent than did the injection of 4 million microspheres. Anesthesia exerted no influence on blood flow other than raising coronary flow. The authors conclude that although blood flow to the gastric mucosa and the pancreas is sensitive to the minor hemodynamic changes associated with the microsphere technique, replacement of volume loss for reference samples ensures stable blood flow to all organs over a 120-min period.

  4. SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW

    E-Print Network [OSTI]

    santos

    SEISMIC MONITORING OF. CARBON DIOXIDE FLUID FLOW. J. E. Santos. 1. , G. B. Savioli. 2. , J. M. Carcione. 3. , D. Gei. 3. 1. CONICET, IGPUBA, Fac.

  5. Flow Imaging Using MRI: Quantification and Analysis

    E-Print Network [OSTI]

    Jiraraksopakun, Yuttapong

    2010-07-14T23:59:59.000Z

    dynamics (CFD) and the conventional optimal flow imaging based on particle image velocimetry (PIV). The results demonstrated the improvement from the quantification using solely the conventional HARP method....

  6. Measurement of thermodynamics using gradient flow

    E-Print Network [OSTI]

    Masakiyo Kitazawa; Masayuki Asakawa; Tetsuo Hatsuda; Takumi Iritani; Etsuko Itou; Hiroshi Suzuki

    2014-12-15T23:59:59.000Z

    We analyze bulk thermodynamics and correlation functions of the energy-momentum tensor in pure Yang-Mills gauge theory using the energy-momentum tensor defined by the gradient flow and small flow time expansion. Our results on thermodynamic observables are consistent with those obtained by the conventional integral method. The analysis of the correlation function of total energy supports the energy conservation. It is also addressed that these analyses with gradient flow require less statistics compared with the previous methods. All these results suggest that the energy-momentum tensor can be successfully defined and observed on the lattice with moderate numerical costs with the gradient flow.

  7. SOLVENT DISPERSION AND FLOW METER CALCULATION RESULTS

    SciTech Connect (OSTI)

    Nash, C.; Fondeur, F.; Peters, T.

    2013-06-21T23:59:59.000Z

    Savannah River National Laboratory (SRNL) found that the dispersion numbers for the six combinations of CSSX:Next Generation Solvent (NGS) “blend” and pure NGS versus salt solution, caustic wash, and strip aqueous solutions are all good. The dispersion numbers are indications of processability with centrifugal contactors. A comparison of solvent physical and thermal properties shows that the Intek™ solvent flow meter in the plant has a reading biased high versus calibrated flow when NGS is used, versus the standard CSSX solvent. The flow meter, calibrated for CSSX solvent, is predicted to read 2.8 gpm of NGS in a case where the true flow of NGS is 2.16 gpm.

  8. Applications in MPC and Network Flows

    E-Print Network [OSTI]

    2013-05-08T23:59:59.000Z

    control should be performed using the least amount of energy. Network flow ...... some type of energy consumption that we want to minimize. ...... Trends Mach.

  9. Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...

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

    Technologies Program Office Program Manager: Mr. Gurpreet Singh Petrodiesel vs. Biodiesel 2 Primary Breakup Inner Nozzle Flow Influence of Physical and Chemical properties of...

  10. Flow characteristics in underground coal gasification

    SciTech Connect (OSTI)

    Chang, H.L.; Himmelblau, D.M.; Edgar, T.F.

    1982-01-01T23:59:59.000Z

    During the underground coal gasification field test at the Hoe Creek site No. 2, Wyoming, helium pulses were introduced to develop information to characterize the flow field, and to estimate the coefficients in dispersion models of the flow. Quantitative analysis of the tracer response curves shows an increasing departure from a plug flow regime with time because of the combined effects of the free and forced convection in addition to the complex non-uniformity of the flow field. The Peclet number was a function of temperature, pressure, gas recovery and characteristic velocity, as well as the split of the gas between the parallel streams in the model. 17 refs.

  11. Smokeless Control of Flare Steam Flow Rate

    E-Print Network [OSTI]

    Agar, J.; Balls, B. W.

    1979-01-01T23:59:59.000Z

    the First Industrial Energy Technology Conference Houston, TX, April 22-25, 1979 FLARE GAS FLOW RATE MEASUREMENT "Accurate measurement of the very low flow rates which are normally present is very difficult" 0, p 15-8). "It is generally considered too...-04-91 Proceedings from the First Industrial Energy Technology Conference Houston, TX, April 22-25, 1979 to calibration conditions. Turndown is 40:1 and pressure loss is negligible. APPLICATION FLOW RATE The mass flow meter described has been applied to a wide...

  12. Sandia National Laboratories: power flow control system

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

    power flow control system ECIS-Princeton Power Systems, Inc.: Demand Response Inverter On March 19, 2013, in DETL, Distribution Grid Integration, Energy, Energy Surety, Facilities,...

  13. A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow...

    Open Energy Info (EERE)

    The Uk Geothermal Catalogue Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow...

  14. The transition from the annular to the slug flow regime in two-phase flow

    E-Print Network [OSTI]

    Haberstroh, Robert D.

    1964-01-01T23:59:59.000Z

    Experiments were conducted to determine the transition from annular to semiannular flow regimes for two-phase, gas-liquid upflow in vertical tubes. The influencesof liquid flow rate, tube diameter, liquid viscosity, surface ...

  15. Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole

    E-Print Network [OSTI]

    Sharipov, Felix

    Tritium flow through a non-symmetrical source. Simulation of gas flow through an injection hole of source in injection rarefaction parameter µ0 viscosity of tritium at T0 Pa s 2 #12;Ll = 5074.5 Lr = 5007

  16. Combustion synthesis continuous flow reactor

    DOE Patents [OSTI]

    Maupin, G.D.; Chick, L.A.; Kurosky, R.P.

    1998-01-06T23:59:59.000Z

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor. 10 figs.

  17. Flow cytometer jet monitor system

    DOE Patents [OSTI]

    Van den Engh, Ger (Seattle, WA)

    1997-01-01T23:59:59.000Z

    A direct jet monitor illuminates the jet of a flow cytometer in a monitor wavelength band which is substantially separate from the substance wavelength band. When a laser is used to cause fluorescence of the substance, it may be appropriate to use an infrared source to illuminate the jet and thus optically monitor the conditions within the jet through a CCD camera or the like. This optical monitoring may be provided to some type of controller or feedback system which automatically changes either the horizontal location of the jet, the point at which droplet separation occurs, or some other condition within the jet in order to maintain optimum conditions. The direct jet monitor may be operated simultaneously with the substance property sensing and analysis system so that continuous monitoring may be achieved without interfering with the substance data gathering and may be configured so as to allow the front of the analysis or free fall area to be unobstructed during processing.

  18. Fluctuating initial conditions and fluctuations in elliptic and triangular flow

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2012-02-24T23:59:59.000Z

    In heavy ion collisions, event-by-event fluctuations in participating nucleon positions can lead to triangular flow. With fluctuating initial conditions, flow coefficients will also fluctuate. In a hydrodynamic model, we study the fluctuations in elliptic and triangular flow, due to fluctuating initial conditions. Both elliptic and triangular flow fluctuates strongly, triangular flow more strongly than the elliptic flow. Strong fluctuations greatly reduce the sensitivity of elliptic and triangular flow to viscosity.

  19. The effects between two slotted plate flow meter under single, two, three components flow condition

    E-Print Network [OSTI]

    Park, Sang Hyan

    2005-02-17T23:59:59.000Z

    suggested a universal calibration for the slotted flow meter under various situations using only the Euler number (Eu) and the ratio of ? = AAslot pipe The calibration curve of the slotted meter?s flow coefficient KY versus Euler number was obtained..., or Three Component Flow Conditions. (December 2004) Sang Hyun Park, B.S., Yonsei University, Republic of Korea Chair of Advisory Committee: Dr. Gerald L. Morrison In previous work on the slotted flow meter, repeatibility and reproducibility were studied...

  20. Network With Costs: Timing and Flow Decomposition

    E-Print Network [OSTI]

    Bruck, Jehoshua (Shuki)

    Network With Costs: Timing and Flow Decomposition Shreeshankar Bodas, Jared Grubb, Sriram Sridharan-- This paper analyzes a capacitated network with costs from an information theoretic point of view. Determines a flow decomposition for a network with costs starting from an information theoretic point of view

  1. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

    2000-02-22T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  2. Solyndra Facts vs. Fiction: Cash Flow Modeling

    Broader source: Energy.gov [DOE]

    Questions have been raised about a quote selectively pulled from an Aug. 20, 2009 email to make it look like Solyndra would run out of cash by Sept. 2011. To be clear, the analysis addressed in that email did not refer to Solyndra’s corporate cash flow, but rather the cash flow for a subsidiary of Solyndra – the “Fab 2 Project Company.

  3. Managing talent flow. 2006 Energy and Resources

    E-Print Network [OSTI]

    and market growth in mining, utilities, oil and gas have been relatively stagnant, prompting many youngManaging talent flow. 2006 Energy and Resources Talent Pulse Survey Report Consulting #12;Executive ................................................................ 13 Contents #12;1 Managing talent flow 2006 Energy and Resources Talent Pulse Survey Report 2006

  4. MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER

    E-Print Network [OSTI]

    Lahey, Richard T.

    MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER "ENGINEERING APPLICATIONS OF FRACTAL AND CHAOS THEORY" RICHARD T. LAHEY, JR. Center for Multiphase Research Rensselaer Polytechnic Institute Troy and multiphase flow & heat transfer will be stressed. This paper will begin by reviewing some important concepts

  5. Global Optimization of Optimal Power Flow

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    /03/2013 4 Power balance Power flows Physical limits Nonconvex constraints #12;8/26/2013 2 SDP Relaxation renewables into the grid e.g., Wind: Hard to forecast. ­ Base load power plants cannot change their output problems. Multi-Period OPF Formulation 12/03/2013 9 Power balance Power flows Physical limits Storage

  6. Fuel cell system with coolant flow reversal

    DOE Patents [OSTI]

    Kothmann, Richard E. (Pittsburgh, PA)

    1986-01-01T23:59:59.000Z

    Method and apparatus for cooling electrochemical fuel cell system components. Periodic reversal of the direction of flow of cooling fluid through a fuel cell stack provides greater uniformity and cell operational temperatures. Flow direction through a recirculating coolant fluid circuit is reversed through a two position valve, without requiring modulation of the pumping component.

  7. DIFFERENTIAL EQUATIONS FOR FLOW IN RESERVOIRS By ...

    E-Print Network [OSTI]

    2008-08-23T23:59:59.000Z

    Darcy's law for each phase with a simple differential material balance for each phase. In this first ... that the pressure declines in the direction of flow. .... lies within some closed curve C across which there is no flow, and fluid injec- tion and ...

  8. Radiative Flow in a Luminous Disk II

    E-Print Network [OSTI]

    Jun Fukue

    2006-01-07T23:59:59.000Z

    Radiatively-driven transfer flow perpendicular to a luminous disk is examined in the subrelativistic regime of $(v/c)^1$, taking into account the gravity of the central object. The flow is assumed to be vertical, and the gas pressure is ignored, while internal heating is assumed to be proportional to the gas density. The basic equations were numerically solved as a function of the optical depth, and the flow velocity, the height, the radiative flux, and the radiation pressure were obtained for a given radius, an initial optical depth, and initial conditions at the flow base (disk ``inside''), whereas the mass-loss rate was determined as an eigenvalue of the boundary condition at the flow top (disk ``surface''). For sufficiently luminous cases, the flow resembles the case without gravity. For less-luminous cases, however, the flow velocity decreases, and the flow would be impossible due to the existence of gravity in the case that the radiative flux is sufficiently small. Application to a supercritical accretion disk with mass loss is briefly discussed.

  9. AIAA 20020413 ACTIVE FLOW CONTROL OF

    E-Print Network [OSTI]

    Jacob, Jamey

    boundary layer and spreads over a significant portion of the wing. This is illustrated in Figure 1 whereAIAA 2002­0413 ACTIVE FLOW CONTROL OF SEPARATION ON A WING WITH OSCILLATORY CAMBER David Munday­4344 #12;AIAA-2002-0413 ACTIVE FLOW CONTROL OF SEPARATION ON A WING WITH OSCILLATORY CAMBER David Munday

  10. Non-Darcy flow in geothermal reservoirs

    SciTech Connect (OSTI)

    Zyvoloski, G.

    1982-01-01T23:59:59.000Z

    The effects of non-Darcy flow laws are investigated for two geothermal reservoir types: multiphase and Hot Dry Rock (HDR). Long-term thermal behavior is emphasized as short-term pressure transient behavior is addressed in the oil field literature. Comparisons of Darcy and non-Darcy flow laws are made.

  11. Groundwater Flow in the Ganges Delta

    E-Print Network [OSTI]

    Entekhabi, Dara

    Groundwater Flow in the Ganges Delta Basu et al. (1) reported that 2 1011 m3 /year of groundwater groundwater than in Ganges-Brahmaputra river water. The flow could also have impli- cations for the origin and fate of other groundwater constituents in the Ganges delta that could be flushed by such rapid regional

  12. Quantitative supersonic flow visualization by hydraulic analogy

    E-Print Network [OSTI]

    Rani, Sarma Laxminarasimha

    1998-01-01T23:59:59.000Z

    The hydraulic analogy, which forms the basis for the phics. current investigation, can be used to study supersonic gas flows with great ease by means of a water table. As a result of the analogy, water heights in free surface water flow correspond...

  13. Flow through electrode with automated calibration

    DOE Patents [OSTI]

    Szecsody, James E [Richland, WA; Williams, Mark D [Richland, WA; Vermeul, Vince R [Richland, WA

    2002-08-20T23:59:59.000Z

    The present invention is an improved automated flow through electrode liquid monitoring system. The automated system has a sample inlet to a sample pump, a sample outlet from the sample pump to at least one flow through electrode with a waste port. At least one computer controls the sample pump and records data from the at least one flow through electrode for a liquid sample. The improvement relies upon (a) at least one source of a calibration sample connected to (b) an injection valve connected to said sample outlet and connected to said source, said injection valve further connected to said at least one flow through electrode, wherein said injection valve is controlled by said computer to select between said liquid sample or said calibration sample. Advantages include improved accuracy because of more frequent calibrations, no additional labor for calibration, no need to remove the flow through electrode(s), and minimal interruption of sampling.

  14. Metallurgical technologies, energy conversion, and magnetohydrodynamic flows

    SciTech Connect (OSTI)

    Branover, H.; Unger, Y.

    1993-01-01T23:59:59.000Z

    The present volume discusses metallurgical applications of MHD, R D on MHD devices employing liquid working medium for process applications, electromagnetic (EM) modulation of molten metal flow, EM pump performance of superconducting MHD devices, induction EM alkali-metal pumps, a physical model for EM-driven flow in channel-induction furnaces, grain refinement in Al alloys via EM vibrational method, dendrite growth of solidifying metal in dc magnetic field, MHD for mass and heat transfer in single-crystal melt growth, inverse EM shaping, and liquid-metal MHD development in Israel. Also discussed are the embrittlement of steel by lead, an open cycle MHD disk generator, the acceleration of gas-liquid piston flows for molten-metal MHD generators, MHD flow around a cylinder, new MHD drag coefficients, liquid-metal MHD two-phase flow, and two-phase liquid gas mixers for MHD energy conversion.

  15. Geometric solitons of Hamiltonian flows on manifolds

    SciTech Connect (OSTI)

    Song, Chong, E-mail: songchong@xmu.edu.cn [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China)] [School of Mathematical Sciences, Xiamen University, Xiamen 361005 (China); Sun, Xiaowei, E-mail: sunxw@cufe.edu.cn [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China)] [School of Applied Mathematics, Central University of Finance and Economics, Beijing 100081 (China); Wang, Youde, E-mail: wyd@math.ac.cn [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)] [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China)

    2013-12-15T23:59:59.000Z

    It is well-known that the LIE (Locally Induction Equation) admit soliton-type solutions and same soliton solutions arise from different and apparently irrelevant physical models. By comparing the solitons of LIE and Killing magnetic geodesics, we observe that these solitons are essentially decided by two families of isometries of the domain and the target space, respectively. With this insight, we propose the new concept of geometric solitons of Hamiltonian flows on manifolds, such as geometric Schrödinger flows and KdV flows for maps. Moreover, we give several examples of geometric solitons of the Schrödinger flow and geometric KdV flow, including magnetic curves as geometric Schrödinger solitons and explicit geometric KdV solitons on surfaces of revolution.

  16. Flow stabilization with active hydrodynamic cloaks

    E-Print Network [OSTI]

    Urzhumov, Yaroslav A; 10.1103/PhysRevE.86.056313

    2012-01-01T23:59:59.000Z

    We demonstrate that fluid flow cloaking solutions based on active hydrodynamic metamaterials exist for two-dimensional flows past a cylinder in a wide range of Reynolds numbers, up to approximately 200. Within the framework of the classical Brinkman equation for homogenized porous flow, we demonstrate using two different methods that such cloaked flows can be dynamically stable for $Re$ in the range 5-119. The first, highly efficient, method is based on a linearization of the Brinkman-Navier-Stokes equation and finding the eigenfrequencies of the least stable eigen-perturbations; the second method is a direct, numerical integration in the time domain. We show that, by suppressing the Karman vortex street in the weekly turbulent wake, porous flow cloaks can raise the critical Reynolds number up to about 120, or five times greater than for a bare, uncloaked cylinder.

  17. Online Supplement Appendix Flow Anatomy of the TCPC Pathways

    E-Print Network [OSTI]

    Pekkan, Kerem

    narrowings that dissipate little power at baseline flows may be sources of significant power loss at increased flows, 2) flow collision between SVC and IVC flows can be a significant source of power loss and usually increases significantly with increasing power loss, 3) increased skewing of the IVC flow toward

  18. Response of a slotted plate flow meter to horizontal two phase flow

    E-Print Network [OSTI]

    Muralidharan, Vasanth

    2005-02-17T23:59:59.000Z

    there is a change in the pipeline geometry or 8 inclination. Severe riser slugging is an example of this effect and it can prevail for kilometers mainly in sea lines. When there are no transient effects or geometry/terrain effects the flow is steady... constant, a static differential pressure due to flow of the pure liquid is attained. 9 Therefore the static differential pressure lines of constant liquid flow rate become horizontal when the gas flow rate is reduced. 4. When the gas flow is increased...

  19. Flow Measurement with Tangential Paddlewheel Flow Meters: Analysis of Experimental Results and in-situ Diagnostics

    E-Print Network [OSTI]

    Watt, J. B.; Haberl, J. S.

    the premature drop-out of magnetic-type tangential paddlewheel sensors, as well as several in-situ diagnostic measures for ascertaining whether or not a flow meter is experiencing turbulent conditions or if a flow sensor's output signal is suffering a degraded... per second for magnetic-type, and 0.5 to 2 feet per second for non-magnetic-type flow sensors deviated from the actual flow by 20% or more which makes the measurement of flow and thermal energy use in this regime highly suspect. Figure 4 also indicates...

  20. Breakthrough Flow Battery Cell Stack: Transformative Electrochemical Flow Storage System (TEFSS)

    SciTech Connect (OSTI)

    None

    2010-09-09T23:59:59.000Z

    GRIDS Project: UTRC is developing a flow battery with a unique design that provides significantly more power than today's flow battery systems. A flow battery is a cross between a traditional battery and a fuel cell. Flow batteries store their energy in external tanks instead of inside the cell itself. Flow batteries have traditionally been expensive because the battery cell stack, where the chemical reaction takes place, is costly. In this project, UTRC is developing a new stack design that achieves 10 times higher power than today’s flow batteries. This high power output means the size of the cell stack can be smaller, reducing the amount of expensive materials that are needed. UTRC’s flow battery will reduce the cost of storing electricity for the electric grid, making widespread use feasible.