National Library of Energy BETA

Sample records for non-isothermal multiphase reactive

  1. TOUGHREACT User's Guide: A Simulation Program for Non-isothermal Multiphase Reactive Geochemical Transport in Variably Saturated Geologic Media, V1.2.1

    SciTech Connect (OSTI)

    Xu, Tianfu; Sonnenthal, Eric; Spycher, Nicolas; Pruess, Karsten

    2008-09-29

    Coupled modeling of subsurface multiphase fluid and heat flow, solute transport, and chemical reactions can be applied to many geologic systems and environmental problems, including geothermal systems, diagenetic and weathering processes, subsurface waste disposal, acid mine drainage remediation, contaminant transport, and groundwater quality. TOUGHREACT has been developed as a comprehensive non-isothermal multi-component reactive fluid flow and geochemical transport simulator to investigate these and other problems. A number of subsurface thermo-physical-chemical processes are considered under various thermohydrological and geochemical conditions of pressure, temperature, water saturation, and ionic strength. TOUGHREACT can be applied to one-, two- or three-dimensional porous and fractured media with physical and chemical heterogeneity. The code can accommodate any number of chemical species present in liquid, gas and solid phases. A variety of equilibrium chemical reactions are considered, such as aqueous complexation, gas dissolution/exsolution, and cation exchange. Mineral dissolution/precipitation can take place subject to either local equilibrium or kinetic controls, with coupling to changes in porosity and permeability and capillary pressure in unsaturated systems. Chemical components can also be treated by linear adsorption and radioactive decay. The first version of the non-isothermal reactive geochemical transport code TOUGHREACT was developed (Xu and Pruess, 1998) by introducing reactive geochemistry into the framework of the existing multi-phase fluid and heat flow code TOUGH2 (Pruess, 1991). TOUGHREACT was further enhanced with the addition of (1) treatment of mineral-water-gas reactive-transport under boiling conditions, (2) an improved HKF activity model for aqueous species, (3) gas species diffusion coefficients calculated as a function of pressure, temperature, and molecular properties, (4) mineral reactive surface area formulations for fractured and porous media, and (5) porosity, permeability, and capillary pressure changes owing to mineral precipitation/dissolution (Sonnenthal et al., 1998, 2000, 2001; Spycher et al., 2003a). Subsequently, TOUGH2 V2 was released with additional EOS modules and features (Pruess et al., 1999). The present version of TOUGHREACT includes all of the previous extensions to the original version, along with the replacement of the original TOUGH2 (Pruess, 1991) by TOUGH2 V2 (Pruess et al., 1999). TOUGHREACT has been applied to a wide variety of problems, some of which are included as examples, such as: (1) Supergene copper enrichment (Xu et al., 2001); (2) Mineral alteration in hydrothermal systems (Xu and Pruess, 2001a; Xu et al., 2004b; Dobson et al., 2004); (3) Mineral trapping for CO{sub 2} disposal in deep saline aquifers (Xu et al., 2003b and 2004a); (4) Coupled thermal, hydrological, and chemical processes in boiling unsaturated tuff for the proposed nuclear waste emplacement site at Yucca Mountain, Nevada (Sonnenthal et al., 1998, 2001; Sonnenthal and Spycher, 2000; Spycher et al., 2003a, b; Xu et al., 2001); (5) Modeling of mineral precipitation/dissolution in plug-flow and fracture-flow experiments under boiling conditions (Dobson et al., 2003); (6) Calcite precipitation in the vadose zone as a function of net infiltration (Xu et al., 2003); and (7) Stable isotope fractionation in unsaturated zone pore water and vapor (Singleton et al., 2004). The TOUGHREACT program makes use of 'self-documenting' features. It is distributed with a number of input data files for sample problems. Besides providing benchmarks for proper code installation, these can serve as a self-teaching tutorial in the use of TOUGHREACT, and they provide templates to help jump-start new applications. The fluid and heat flow part of TOUGHREACT is derived from TOUGH2 V2, so in addition to the current manual, users must have the manual of the TOUGH2 V2 (Pruess et al., 1999). The present version of TOUGHREACT provides the following TOUGH2 fluid property or 'EOS' (equation-of-state) modules: (1) EOS1 for

  2. TOUGHREACT: A Simulation Program for Non-isothermal Multiphase...

    Office of Scientific and Technical Information (OSTI)

    ... Journal of Geophysical Research, v. 106 (B2), p. 2121-2138. Xu, T., Pruess, K., 2001b. ... and reactive geochemical transport in variably saturated fractured rocks: 1. Methodology. ...

  3. Multiphase flow and multicomponent reactive transport model of the ventilation experiment in Opalinus clay

    SciTech Connect (OSTI)

    Zheng, L.; Samper, J.; Montenegro, L.; Major, J.C.

    2008-10-15

    During the construction and operational phases of a high-level radioactive waste (HLW) repository constructed in a clay formation, ventilation of underground drifts will cause desaturation and oxidation of the rock. The Ventilation Experiment (VE) was performed in a 1.3 m diameter unlined horizontal microtunnel on Opalinus clay at Mont Terri underground research laboratory in Switzerland to evaluate the impact of desaturation on rock properties. A multiphase flow and reactive transport model of VE is presented here. The model accounts for liquid, vapor and air flow, evaporation/condensation and multicomponent reactive solute transport with kinetic dissolution of pyrite and siderite and local-equilibrium dissolution/precipitation of calcite, ferrihydrite, dolomite, gypsum and quartz. Model results reproduce measured vapor flow, liquid pressure and hydrochemical data and capture the trends of measured relative humidities, although such data are slightly overestimated near the rock interface due to uncertainties in the turbulence factor. Rock desaturation allows oxygen to diffuse into the rock and triggers pyrite oxidation, dissolution of calcite and siderite, precipitation of ferrihydrite, dolomite and gypsum and cation exchange. pH in the unsaturated rock varies from 7.8 to 8 and is buffered by calcite. Computed changes in the porosity and the permeability of Opalinus clay in the unsaturated zone caused by oxidation and mineral dissolution/precipitation are smaller than 5%. Therefore, rock properties are not expected to be affected significantly by ventilation of underground drifts during construction and operational phases of a HLW repository in clay.

  4. Subsurface Multiphase Flow and Multicomponent Reactive Transport Modeling using High-Performance Computing

    SciTech Connect (OSTI)

    Hammond, Glenn E.; Lichtner, Peter C.; Lu, Chuan

    2007-07-16

    Numerical modeling has become a critical tool to the U.S. Department of Energy for evaluating the environmental impact of alternative energy sources and remediation strategies for legacy waste sites. Unfortunately, the physical and chemical complexity of many sites overwhelms the capabilities of even most “state of the art” groundwater models. Of particular concern are the representation of highly-heterogeneous stratified rock/soil layers in the subsurface and the biological and geochemical interactions of chemical species within multiple fluid phases. Clearly, there is a need for higher-resolution modeling (i.e. more spatial, temporal, and chemical degrees of freedom) and increasingly mechanistic descriptions of subsurface physicochemical processes. We present SciDAC-funded research being performed in the development of PFLOTRAN, a parallel multiphase flow and multicomponent reactive transport model. Written in Fortran90, PFLOTRAN is founded upon PETSc data structures and solvers. We are employing PFLOTRAN in the simulation of uranium transport at the Hanford 300 Area, a contaminated site of major concern to the Department of Energy, the State of Washington, and other government agencies. By leveraging the billions of degrees of freedom available through high-performance computation using tens of thousands of processors, we can better characterize the release of uranium into groundwater and its subsequent transport to the Columbia River, and thereby better understand and evaluate the effectiveness of various proposed remediation strategies.

  5. Subsurface Multiphase Flow and Multicomponent Reactive Transport Modeling using High-Performance Computing

    SciTech Connect (OSTI)

    Hammond, Glenn E.; Lichtner, Peter C.; Lu, Chuan

    2007-08-01

    Numerical modeling has become a critical tool to the Department of Energy for evaluating the environmental impact of alternative energy sources and remediation strategies for legacy waste sites. Unfortunately, the physical and chemical complexity of many sites overwhelms the capabilities of even most “state of the art” groundwater models. Of particular concern are the representation of highly-heterogeneous stratified rock/soil layers in the subsurface and the biological and geochemical interactions of chemical species within multiple fluid phases. Clearly, there is a need for higher-resolution modeling (i.e. more spatial, temporal, and chemical degrees of freedom) and increasingly mechanistic descriptions of subsurface physicochemical processes. We present research being performed in the development of PFLOTRAN, a parallel multiphase flow and multicomponent reactive transport model. Written in Fortran90, PFLOTRAN is founded upon PETSc data structures and solvers and has exhibited impressive strong scalability on up to 4000 processors on the ORNL Cray XT3. We are employing PFLOTRAN in the simulation of uranium transport at the Hanford 300 Area, a contaminated site of major concern to the Department of Energy, the State of Washington, and other government agencies where overly-simplistic historical modeling erroneously predicted decade removal times for uranium by ambient groundwater flow. By leveraging the billions of degrees of freedom available through high-performance computation using tens of thousands of processors, we can better characterize the release of uranium into groundwater and its subsequent transport to the Columbia River, and thereby better understand and evaluate the effectiveness of various proposed remediation strategies.

  6. Reactive transport modeling of stable carbon isotope fractionation in a multi-phase multi-component system during carbon sequestration

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

    Zhang, Shuo; DePaolo, Donald J.; Zheng, Liange; Mayer, Bernhard

    2014-12-31

    Carbon stable isotopes can be used in characterization and monitoring of CO2 sequestration sites to track the migration of the CO2 plume and identify leakage sources, and to evaluate the chemical reactions that take place in the CO2-water-rock system. However, there are few tools available to incorporate stable isotope information into flow and transport codes used for CO2 sequestration problems. We present a numerical tool for modeling the transport of stable carbon isotopes in multiphase reactive systems relevant to geologic carbon sequestration. The code is an extension of the reactive transport code TOUGHREACT. The transport module of TOUGHREACT was modifiedmore » to include separate isotopic species of CO2 gas and dissolved inorganic carbon (CO2, CO32-, HCO3-,…). Any process of transport or reaction influencing a given carbon species also influences its isotopic ratio. Isotopic fractionation is thus fully integrated within the dynamic system. The chemical module and database have been expanded to include isotopic exchange and fractionation between the carbon species in both gas and aqueous phases. The performance of the code is verified by modeling ideal systems and comparing with theoretical results. Efforts are also made to fit field data from the Pembina CO2 injection project in Canada. We show that the exchange of carbon isotopes between dissolved and gaseous carbon species combined with fluid flow and transport, produce isotopic effects that are significantly different from simple two-component mixing. These effects are important for understanding the isotopic variations observed in field demonstrations.« less

  7. Reactive transport modeling of stable carbon isotope fractionation in a multi-phase multi-component system during carbon sequestration

    SciTech Connect (OSTI)

    Zhang, Shuo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DePaolo, Donald J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zheng, Liange [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mayer, Bernhard [Univ. of Calgary (Canada). Dept. of Geosciences

    2014-12-31

    Carbon stable isotopes can be used in characterization and monitoring of CO2 sequestration sites to track the migration of the CO2 plume and identify leakage sources, and to evaluate the chemical reactions that take place in the CO2-water-rock system. However, there are few tools available to incorporate stable isotope information into flow and transport codes used for CO2 sequestration problems. We present a numerical tool for modeling the transport of stable carbon isotopes in multiphase reactive systems relevant to geologic carbon sequestration. The code is an extension of the reactive transport code TOUGHREACT. The transport module of TOUGHREACT was modified to include separate isotopic species of CO2 gas and dissolved inorganic carbon (CO2, CO32-, HCO3-,…). Any process of transport or reaction influencing a given carbon species also influences its isotopic ratio. Isotopic fractionation is thus fully integrated within the dynamic system. The chemical module and database have been expanded to include isotopic exchange and fractionation between the carbon species in both gas and aqueous phases. The performance of the code is verified by modeling ideal systems and comparing with theoretical results. Efforts are also made to fit field data from the Pembina CO2 injection project in Canada. We show that the exchange of carbon isotopes between dissolved and gaseous carbon species combined with fluid flow and transport, produce isotopic effects that are significantly different from simple two-component mixing. These effects are important for understanding the isotopic variations observed in field demonstrations.

  8. REACTIVE MULTIPHASE BEHAVIOR OF CO2 IN SALINE AQUIFERS BENEATH THE COLORADO PLATEAU

    SciTech Connect (OSTI)

    R.G. Allis; J. Moore; S. White

    2003-01-30

    Gas reservoirs developed within the Colorado Plateau and Southern Rocky Mountains region are natural laboratories for studying the factors that promote long-term storage of CO{sub 2}. They also provide sites for storing additional CO{sub 2} if it can be separated from the flue gases of coal-fired power plants in this part of the U.S.A. These natural reservoirs are developed primarily in sandstones and dolomites; shales, mudstones and anhydrite form seals. In many fields, stacked reservoirs are present, indicating that the gas has migrated up through the section. There are also geologically young travertine deposits at the surface, and CO{sub 2}-charged groundwater and springs in the vicinity of known CO{sub 2} occurrences. These near-surface geological and hydrological features also provide examples of the environmental effects of leakage of CO{sub 2} from reservoirs, and justify further study. During reporting period covered here (the first quarter of Year 3 of the project, i.e. October 1-December 31, 2002), the main achievements were: (1) Planning workshop for project participants as well as other Utah researchers involved in CO{sub 2} projects (22 October, 2002), and Utah Geological Survey, Salt Lake City; (2) Presentation of paper to special CO{sub 2} sequestration session at the Geological Society of America Annual Meeting, Denver, 29 October, 2002; (3) Presentation of paper to special CO{sub 2} sequestration session at the Fall Meeting of American Geophysical Union, San Francisco, 10 December, 2002; (4) Identification of dawsonite (sodium-aluminum carbonate) as a late stage mineral deposited in CO{sub 2} feedzone at Springerville, Arizona; (5) Successful matching of known physical constraints to flow beneath the Hunter cross section being used to simulate the effects of CO{sub 2} injection. In about 1000 years, most injected CO{sub 2} may be lost to the surface from the three shallowest reservoirs considered, assuming no reactive processes; and (6) Inclusion of reactive processes in numerical simulations, and indication that CO{sub 2} is sequestered for at 1000 years in form of dissolved CO{sub 2} and carbonate mineral precipitation.

  9. Rarefied gas flow in a rectangular enclosure induced by non-isothermal walls

    SciTech Connect (OSTI)

    Vargas, Manuel; Tatsios, Giorgos; Valougeorgis, Dimitris; Stefanov, Stefan

    2014-05-15

    The flow of a rarefied gas in a rectangular enclosure due to the non-isothermal walls with no synergetic contributions from external force fields is investigated. The top and bottom walls are maintained at constant but different temperatures and along the lateral walls a linear temperature profile is assumed. Modeling is based on the direct numerical solution of the Shakhov kinetic equation and the Direct Simulation Monte Carlo (DSMC) method. Solving the problem both deterministically and stochastically allows a systematic comparison and verification of the results as well as the exploitation of the numerical advantages of each approach in the investigation of the involved flow and heat transfer phenomena. The thermally induced flow is simulated in terms of three dimensionless parameters characterizing the problem, namely, the reference Knudsen number, the temperature ratio of the bottom over the top plates, and the enclosure aspect ratio. Their effect on the flow configuration and bulk quantities is thoroughly examined. Along the side walls, the gas flows at small Knudsen numbers from cold-to-hot, while as the Knudsen number is increased the gas flows from hot-to-cold and the thermally induced flow configuration becomes more complex. These flow patterns with the hot-to-cold flow to be extended to the whole length of the non-isothermal side walls may exist even at small temperature differences and then, they are enhanced as the temperature difference between the top and bottom plates is increased. The cavity aspect ratio also influences this flow configuration and the hot-to-cold flow is becoming more dominant as the depth compared to the width of the cavity is increased. To further analyze the flow patterns a novel solution decomposition into ballistic and collision parts is introduced. This is achieved by accordingly modifying the indexing process of the typical DSMC algorithm. The contribution of each part of the solution is separately examined and a physical interpretation of the flow configuration, including the hot-to-cold flow close to the side walls, in the whole range of the Knudsen number is provided.

  10. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15

    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.

  11. Geothermal Technologies Office Annual Report 2012

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

    ... for chemically reactive non- isothermal flows of multiphase fluids in porous and ... Survey (USGS), drilled seven geothermal gradient holes in Utah's Black Rock Desert basin ...

  12. Multiphase fluid characterization system

    DOE Patents [OSTI]

    Sinha, Dipen N.

    2014-09-02

    A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.

  13. Germanium multiphase equation of state

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

    Crockett, Scott D.; Lorenzi-Venneri, Giulia De; Kress, Joel D.; Rudin, Sven P.

    2014-05-07

    A new SESAME multiphase germanium equation of state (EOS) has been developed using the best available experimental data and density functional theory (DFT) calculations. The equilibrium EOS includes the Ge I (diamond), the Ge II (β-Sn) and the liquid phases. The foundation of the EOS is based on density functional theory calculations which are used to determine the cold curve and the Debye temperature. Results are compared to Hugoniot data through the solid-solid and solid-liquid transitions. We propose some experiments to better understand the dynamics of this element

  14. Multiphase Flow Analysis in Hydra-TH

    SciTech Connect (OSTI)

    Christon, Mark A.; Bakosi, Jozsef; Francois, Marianne M.; Lowrie, Robert B.; Nourgaliev, Robert

    2012-06-20

    This talk presents an overview of the multiphase flow efforts with Hydra-TH. The presentation begins with a definition of the requirements and design principles for multiphase flow relevant to CASL-centric problems. A brief survey of existing codes and their solution algorithms is presented before turning the model formulation selected for Hydra-TH. The issues of hyperbolicity and wellposedness are outlined, and a three candidate solution algorithms are discussed. The development status of Hydra-TH for multiphase flow is then presented with a brief summary and discussion of future directions for this work.

  15. An update on subsea multiphase pumping

    SciTech Connect (OSTI)

    Colombi, P.; De Donno, S.

    1996-02-01

    Agip SpA anticipates that subsea multiphase production, based on long-distance transportation of untreated oilwell fluids--namely, oil, water, and gas, will be an efficient tool for the exploitation of deepwater and marginal fields. In 1990, at the Trecate onshore oil field, Agip completed long-term testing of a multiphase screw pump, which confirmed commercial surface applications. Agip then integrated a subsea version of an improved multiphase twin-screw pump into a subsea multiphase boosting unit that was installed at the Prezioso field, offshore Sicily, in 1994 That was the first subsea installation of an electrically driven multi-phase pump operating with live oil. Agip began endurance testing of the pumping system in January 1995 and by last November, the cumulated period of running reached 3,500 hours with no evidence of pump-capacity reduction. Testing focused on boosting at high gas-void fraction and oil viscosity, operation at variable motor speed for pump control, pump control by means of throttling valves, direct interaction of the pumping system with both wells and the multiphase export line, variation of the lube-oil pressure across seals and bearings, and the evaluation of any degradation effect on the pump flow capacity over time. This paper reviews the design and performance of this pump and applicability to other offshore projects.

  16. On-line subsea multiphase flow measurement

    SciTech Connect (OSTI)

    High, G.; Frantzen, K.H.; Marshall, M.

    1995-12-31

    This paper describes the final detailed design, engineering, and installation phase of a Joint Industry Program to qualify a robust subsea multiphase flowmeter module for long-term installation on a North Sea manifold tie-in. Multiphase subsea production has become a common method of hydrocarbon recovery in all areas of offshore E and P. In the North Sea, many developments are subsea satellites with multiphase well-fluids being comingled prior to processing. The system described meets this challenge by offering a cost effective solution to real-time well monitoring as an alternative to the conventional test separator, removing the need for test lines and shutting in wells for testing. The multiphase instrument allows on-line well fluid analysis, and is also an important tool for reservoir management and field analysis, and provides a means of implementing field allocation metering thereby simplifying small marginal field developments. This project is one of the first subsea multiphase flowmeter installations engineered for long-term subsea service, and designed as an integrated component of the subsea production control system.

  17. Modified Invasion Percolation Models for Multiphase Processes

    SciTech Connect (OSTI)

    Karpyn, Zuleima

    2015-01-31

    This project extends current understanding and modeling capabilities of pore-scale multiphase flow physics in porous media. High-resolution X-ray computed tomography imaging experiments are used to investigate structural and surface properties of the medium that influence immiscible displacement. Using experimental and computational tools, we investigate the impact of wetting characteristics, as well as radial and axial loading conditions, on the development of percolation pathways, residual phase trapping and fluid-fluid interfacial areas.

  18. On the threshold -- Subsea multiphase pumping

    SciTech Connect (OSTI)

    Beran, W.T.

    1995-04-01

    Satellite subsea production systems are attractive as a low-cost approach to field development, particularly for so-called marginal fields in deepwater areas. Development of such fields may be uneconomical, however, if the natural wellhead flowing pressure is too low. This paper presents an update on the state of subsea multiphase-pumping-system technology. The potential production benefits of subsea pressure-boosting systems.

  19. Liquid-based gating mechanism with tunable multiphase selectivity...

    Office of Scientific and Technical Information (OSTI)

    selectivity and antifouling behaviour Prev Next Title: Liquid-based gating mechanism with tunable multiphase selectivity and antifouling behaviour You are accessing a ...

  20. Liquid-based gating mechanism with tunable multiphase selectivity...

    Office of Scientific and Technical Information (OSTI)

    selectivity and antifouling behaviour Prev Next Title: Liquid-based gating mechanism with tunable multiphase selectivity and antifouling behaviour Living organisms make ...

  1. Multiphase Flow Metering: An Overview Manoj Kumar KM, Senior...

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

    dependency can be eliminated from the total mass flow rate estimation. Novel data analytics for reliable flow rate estimation: Data handling is critical in a multiphase...

  2. Multiphase pumps and flow meters avoid platform construction

    SciTech Connect (OSTI)

    Elde, J.

    1999-02-01

    One of the newest wrinkles in efficiency in BP`s Eastern Trough Area Project (ETAP) is the system for moving multiphase oil, water and gas fluids from the Machar satellite field to the Marnock Central Processing Facility (CPF). Using water-turbine-driven multiphase pumps and multiphase flow meters, the system moves fluid with no need for a production platform. In addition, BP has designed the installation so it reduces and controls water coning, thereby increasing recoverable reserves. Both subsea multiphase booster stations (SMUBS) and meters grew out of extensive development work and experience at Framo Engineering AS (Framo) in multiphase meters and multiphase pump systems for subsea installation. Multiphase meter development began in 1990 and the first subsea multiphase meters were installed in the East Spar Project in Australia in 1996. By September 1998, the meters had been operating successfully for more than 1 year. A single multiphase meter installed in Marathon`s West Brae Project has also successfully operated for more than 1 year. Subsea meters for ETAP were installed and began operating in July 1998.

  3. Kinetic Theory of Turbulent Multiphase Flow | The Ames Laboratory

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

    Kinetic Theory of Turbulent Multiphase Flow FWPProject Description: Project Leader(s): Rodney Fox It is proposed to further the present understanding of turbulent gas-solid...

  4. Liquid-based gating mechanism with tunable multiphase selectivity and

    Office of Scientific and Technical Information (OSTI)

    antifouling behaviour (Journal Article) | DOE PAGES Liquid-based gating mechanism with tunable multiphase selectivity and antifouling behaviour « Prev Next » Title: Liquid-based gating mechanism with tunable multiphase selectivity and antifouling behaviour Living organisms make extensive use of micro- and nanometre-sized pores as gatekeepers for controlling the movement of fluids, vapours and solids between complex environments. In addition, the ability of such pores to coordinate

  5. Technical Report on NETL's Non Newtonian Multiphase Slurry Workshop: A path forward to understanding non-Newtonian multiphase slurry flows

    SciTech Connect (OSTI)

    Edited by Guenther, Chris; Garg, Rahul

    2013-08-19

    The Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) sponsored a workshop on non-Newtonian multiphase slurry at NETL’s Morgantown campus August 19 and 20, 2013. The objective of this special two-day meeting of 20-30 invited experts from industry, National Labs and academia was to identify and address technical issues associated with handling non-Newtonian multiphase slurries across various facilities managed by DOE. Particular emphasis during this workshop was placed on applications managed by the Office of Environmental Management (EM). The workshop was preceded by two webinars wherein personnel from ORP and NETL provided background information on the Hanford WTP project and discussed the critical design challenges facing this project. In non-Newtonian fluids, viscosity is not constant and exhibits a complex dependence on applied shear stress or deformation. Many applications under EM’s tank farm mission involve non-Newtonian slurries that are multiphase in nature; tank farm storage and handling, slurry transport, and mixing all involve multiphase flow dynamics, which require an improved understanding of the mechanisms responsible for rheological changes in non-Newtonian multiphase slurries (NNMS). To discuss the issues in predicting the behavior of NNMS, the workshop focused on two topic areas: (1) State-of-the-art in non-Newtonian Multiphase Slurry Flow, and (2) Scaling up with Confidence and Ensuring Safe and Reliable Long-Term Operation.

  6. Quantitative tomographic measurements of opaque multiphase flows

    SciTech Connect (OSTI)

    GEORGE,DARIN L.; TORCZYNSKI,JOHN R.; SHOLLENBERGER,KIM ANN; O'HERN,TIMOTHY J.; CECCIO,STEVEN L.

    2000-03-01

    An electrical-impedance tomography (EIT) system has been developed for quantitative measurements of radial phase distribution profiles in two-phase and three-phase vertical column flows. The EIT system is described along with the computer algorithm used for reconstructing phase volume fraction profiles. EIT measurements were validated by comparison with a gamma-densitometry tomography (GDT) system. The EIT system was used to accurately measure average solid volume fractions up to 0.05 in solid-liquid flows, and radial gas volume fraction profiles in gas-liquid flows with gas volume fractions up to 0.15. In both flows, average phase volume fractions and radial volume fraction profiles from GDT and EIT were in good agreement. A minor modification to the formula used to relate conductivity data to phase volume fractions was found to improve agreement between the methods. GDT and EIT were then applied together to simultaneously measure the solid, liquid, and gas radial distributions within several vertical three-phase flows. For average solid volume fractions up to 0.30, the gas distribution for each gas flow rate was approximately independent of the amount of solids in the column. Measurements made with this EIT system demonstrate that EIT may be used successfully for noninvasive, quantitative measurements of dispersed multiphase flows.

  7. Plasmas in Multiphase Media: Bubble Enhanced Discharges in Liquids and Plasma/Liquid Phase Boundaries

    SciTech Connect (OSTI)

    Kushner, Mark Jay

    2014-07-10

    In this research project, the interaction of atmospheric pressure plasmas with multi-phase media was computationally investigated. Multi-phase media includes liquids, particles, complex materials and porous surfaces. Although this investigation addressed fundamental plasma transport and chemical processes, the outcomes directly and beneficially affected applications including biotechnology, medicine and environmental remediation (e.g., water purification). During this project, we made advances in our understanding of the interaction of atmospheric pressure plasmas in the form of dielectric barrier discharges and plasma jets with organic materials and liquids. We also made advances in our ability to use computer modeling to represent these complex processes. We determined the method that atmospheric pressure plasmas flow along solid and liquid surfaces, and through endoscopic like tubes, deliver optical and high energy ion activation energy to organic and liquid surfaces, and produce reactivity in thin liquid layers, as might cover a wound. We determined the mechanisms whereby plasmas can deliver activation energy to the inside of liquids by sustaining plasmas in bubbles. These findings are important to the advancement of new technology areas such as plasma medicine

  8. Multiphase Flow Modeling of Biofuel Production Processes

    SciTech Connect (OSTI)

    D. Gaston; D. P. Guillen; J. Tester

    2011-06-01

    As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.

  9. National laboratories` capabilities summaries for the DOE Virtual Center for Multiphase Dynamics (VCMD)

    SciTech Connect (OSTI)

    Joyce, E.L.

    1997-03-01

    The Virtual Center For Multiphase Dynamics (VCMD) integrates and develops the resources of industry, government, academia, and professional societies to enable reliable analysis in multiphase computational fluid dynamics. The primary means of the VCMD focus will be by the creation, support, and validation of a computerized simulation capability for multiphase flow and multiphase flow applications. This paper briefly describes the capabilities of the National Laboratories in this effort.

  10. The experience from field operation of a subsea multiphase booster

    SciTech Connect (OSTI)

    De Donno, S.; Colombi, P.; Chiesa, G.; Ferrari Aggradi, G.

    1995-12-31

    The subsea multiphase production -- based on the transportation over long distance of the untreated oil-well fluids (oil, water and gas) -- is expected to be one of the most efficient tool for economic exploitation of deep offshore and marginal fields. A long term testing campaign on a multiphase screw pump was successfully completed in 1990 at the AGIP Trecate onshore oil field and the results confirmed the industrial viability for such a kind of equipment for surface application. Then, a subsea version of an improved multiphase twin screw pump has been integrated into a Subsea Multiphase Boosting Unit and installed on the Prezioso Field, offshore Sicily, in Summer 1994. Long term testing under real operating conditions were initiated after a successful start-up of the Unit. To the Authors` knowledge, this is the first world-wide subsea installation of an electrically driven multiphase pump operating with live oil. The paper presents first a description of the marine twin screw pump concept adopted for the subsea application including the main features of the complete boosting unit and the adopted solutions to allow it to operate under different conditions. Then, the project implementation activities from the onshore integration through the installation, commissioning and start-up operations are described. Moreover, the results of the initial functional tests are discussed with particular reference to the screw pump hydraulic performance as well as to the behavior of the pump pressure compensation and seal/lube oil systems. Transient and steady state conditions experienced by the system are finally characterized and the early evidences of its long term performance are discussed.

  11. REACTIVE MULTIPHASE BEHAVIOR OF CO2 IN SALINE AQUIFERS BENEATH THE COLORADO PLATEAU

    SciTech Connect (OSTI)

    R.G. Allis; J. Moore; S. White

    2003-10-21

    Field and laboratory investigations of naturally occurring CO{sub 2}-reservoirs are being conducted to determine the characteristics of potential seal and reservoir units and the extent of the interactions that occur between the host rocks and the CO{sub 2} charged fluids. Efforts have focused on the Farnham Dome field, located in central Utah, and the Springerville-St. Johns field in Arizona and New Mexico. The Springerville-St. Johns field is particularly significant because of the presence of extensive travertine deposits that document release of CO{sub 2} to the atmosphere. CO{sub 2} accumulations at both fields occur in sedimentary rocks typical of CO{sub 2} reservoirs occurring on the Colorado Plateau. The main achievements during this quarter were: (1) a soil gas flux survey at the Springerville-St Johns field, (2) collection of some soil gas for chemical and isotopic analysis from this field, and (3) collection of travertine samples from an elevation range of over 1000 feet (330 m) for dating the time span of carbonate-saturated spring outflow at this field. Analytical results and interpretations are still in progress. When available they will allow contrast with soil gas measurements from Farnham Dome natural CO{sub 2} field in central Utah, which were reported in the previous quarterly report.

  12. REACTIVE MULTIPHASE BEHAVIOR OF CO2 IN SALINE AQUIFERS BENEATH THE COLORADO PLATEAU

    SciTech Connect (OSTI)

    R.G. Allis; J. Moore; S. White

    2003-06-30

    The six coal-fired power plants located in the Colorado Plateau and southern Rocky Mountain region of the U.S. produce 100 million tons of CO{sub 2} per year. Thick sequences of collocated sedimentary rocks represent potential sites for sequestration of the CO{sub 2}. Field and laboratory investigations of naturally occurring CO{sub 2}-reservoirs are being conducted to determine the characteristics of potential seal and reservoir units and the extent of the interactions that occur between the host rocks and the CO{sub 2} charged fluids. The results are being incorporated into a series of two-dimensional numerical models that represent the major chemical and physical processes induced by injection. During reporting period covered here (March 30 to June 30, 2003), the main achievements were: Presentation of three papers at the Second Annual Conference on Carbon Sequestration (May 5-8, Alexandria, Virginia); Presentation of a poster at the American Association of Petroleum Geologists meeting; Co-PI organized and chaired a special session on Geologic Carbon Dioxide Sequestration at the American Association of Petroleum Geologists annual convention in Salt Lake City (May 12-15).

  13. Method for producing nanocrystalline multicomponent and multiphase materials

    DOE Patents [OSTI]

    Eastman, Jeffrey A. (Woodridge, IL); Rittner, Mindy N. (Des Plaines, IL); Youngdahl, Carl J. (Westmont, IL); Weertman, Julia R. (Evanston, IL)

    1998-01-01

    A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound.

  14. Method for producing nanocrystalline multicomponent and multiphase materials

    DOE Patents [OSTI]

    Eastman, J.A.; Rittner, M.N.; Youngdahl, C.J.; Weertman, J.R.

    1998-03-17

    A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound. 6 figs.

  15. System for measuring multiphase flow using multiple pressure differentials

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-01-01

    An improved method and system for measuring a multi-phase flow in a pressure flow meter. An extended throat venturi is used and pressure of the multi-phase flow is measured at three or more positions in the venturi, which define two or more pressure differentials in the flow conduit. The differential pressures are then used to calculate the mass flow of the gas phase, the total mass flow, and the liquid phase. The system for determining the mass flow of the high void fraction fluid flow and the gas flow includes taking into account a pressure drop experienced by the gas phase due to work performed by the gas phase in accelerating the liquid phase.

  16. CASL-8-2015-0103-000 Multi-Phase Flow: Direct Numerical Simulation

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

    3-000 Multi-Phase Flow: Direct Numerical Simulation Igor Bolotnov North Carolina State University Gretar Tryggvason University of Notre Dame July 8-10, 2013 CASL-U-2015-0103-000 Multi-Phase Flow: Direct Numerical Simulation Multi-Phase Flow: Direct Numerical Simulation Igor Bolotnov - North Carolina State University Gretar Tryggvason - University of Notre Dame CASL Education Workshop, Oak Ridge National Laboratories, July 9-10, 2013 CASL-U-2015-0103-000 Multi-Phase Flow: Direct Numerical

  17. Multi-phase back contacts for CIS solar cells

    DOE Patents [OSTI]

    Rockett, Angus A. (505 Park Haven Ct., Champaign, IL 61820); Yang, Li-Chung (1107 W. Green St. #328, Urbana, IL 61801)

    1995-01-01

    Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe.sub.2 where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Mo back layer. Solar cells employing In-rich CIS semiconductors bonded to the multi-phase columnar microstructure back layer of this invention exhibit vastly improved photo-electrical conversion on the order of 17% greater than Mo alone, improved uniformity of output across the face of the cell, and greater Fill Factor.

  18. Multi-phase back contacts for CIS solar cells

    DOE Patents [OSTI]

    Rockett, A.A.; Yang, L.C.

    1995-12-19

    Multi-phase, single layer, non-interdiffusing M-Mo back contact metallized films, where M is selected from Cu, Ga, or mixtures thereof, for CIS cells are deposited by a sputtering process on suitable substrates, preferably glass or alumina, to prevent delamination of the CIS from the back contact layer. Typical CIS compositions include CuXSe{sub 2} where X is In or/and Ga. The multi-phase mixture is deposited on the substrate in a manner to provide a columnar microstructure, with micro-vein Cu or/and Ga regions which partially or fully vertically penetrate the entire back contact layer. The CIS semiconductor layer is then deposited by hybrid sputtering and evaporation process. The Cu/Ga-Mo deposition is controlled to produce the single layer two-phase columnar morphology with controllable Cu or Ga vein size less than about 0.01 microns in width. During the subsequent deposition of the CIS layer, the columnar Cu/Ga regions within the molybdenum of the Cu/Ga-Mo back layer tend to partially leach out, and are replaced by columns of CIS. Narrower Cu and/or Ga regions, and those with fewer inner connections between regions, leach out more slowly during the subsequent CIS deposition. This gives a good mechanical and electrical interlock of the CIS layer into the Cu/Ga-Mo back layer. Solar cells employing In-rich CIS semiconductors bonded to the multi-phase columnar microstructure back layer of this invention exhibit vastly improved photo-electrical conversion on the order of 17% greater than Mo alone, improved uniformity of output across the face of the cell, and greater Fill Factor. 15 figs.

  19. Developing a subsea multiphase-flow pumping system

    SciTech Connect (OSTI)

    1997-08-01

    Since 1995, Petrobras and Westinghouse have been working on a development effort that has resulted in a technological cooperation agreement between the companies and, more importantly, the development of a conceptual design for a subsea multiphase-flow pumping system. SBMS-500 [500-m{sup 3}/hr total flow rate, up to 6,000 KPa of pressure increase, up to 95% gas-void fraction (GVF) at the suction, and approximately 1.2 MW of power on the shaft], adequate for deepwater guidelineless operations. In 1992, having discovered fields in water depths greater than the original 1,000-m limit. Petrobras created a new program named Procap-2000 (technological-innovation program for deepwater exploitation systems). Among the innovative technological endeavors that Procap comprises are the boosting projects, namely the electrical submersible downhole pump in subsea wells; a subsea liquid-separation system; and a subsea multiphase-flow pumping system (SMFPS). Major characteristics and plans for field testing are described.

  20. April 2013 Most Viewed Documents for Geosciences | OSTI, US Dept...

    Office of Scientific and Technical Information (OSTI)

    FRACTURED RESERVOIRS IN CARBONATE ROCKS: THE MICHIGAN BASIN James R. Wood; William B. Harrison (2002) 43 TOUGHREACT User's Guide: A Simulation Program for Non-isothermal Multiphase ...

  1. MULTI-PHASE FRACTURE-MATRIX INTERACTIONS UNDER STRESS CHANGES

    SciTech Connect (OSTI)

    A.S. Grader; D. Elsworth; P.M. Halleck; F. Alvarado; A. Alajmi; Z. Karpyn; N. Mohammed; S. Al-Enezi

    2005-06-15

    The main objectives of this project are to quantify the changes in fracture porosity and multiphase transport properties as a function of confining stress. These changes will be integrated into conceptual and numerical models that will improve our ability to predict and optimize fluid transport in fractured system. This report details our progress on: (a) developing the direct experimental measurements of fracture aperture and topology and fluid occupancy using high-resolution x-ray micro-tomography, (b) quantifying the effect of confining stress on the distribution of fracture aperture, and (c) characterization of shear fractures and their impact on multi-phase flow. The three-dimensional surface that describes the large-scale structure of the fracture in the porous medium can be determined using x-ray micro-tomography with significant accuracy. Several fractures have been scanned and the fracture aperture maps have been extracted. The success of the mapping of fracture aperture was followed by measuring the occupancy of the fracture by two immiscible phases, water and decane, and water and kerosene. The distribution of fracture aperture depends on the effective confining stress on the nature of the rock and the type and distribution of the asperities that keep the fracture open. Fracture apertures at different confining stresses were obtained by micro-tomography covering a range of about two thousand psig. Initial analysis of the data shows a significant aperture closure with increase in effective confining stress. Visual descriptions of the process are shown in the report while detailed analysis of the behavior of the distribution of fracture aperture is in progress. Both extensional and shear fractures are being considered. The initial multi-phase flow tests were done in extensional fractures. Several rock samples with induced shear fracture are being studied, and some of the new results are presented in this report. These samples are being scanned in order to quantify the distribution of apertures and the nature of the asperities. Low resolution images of fluids in a sample with a shear fracture were performed and they provide the confidence that flow patterns and saturations could be determined in the future. A series of water imbibition tests were conducted in which water was injected into a fracture and its migration into the matrix was monitored with CT and DR x-ray techniques. The objective is to understand the impact of the fracture, its topology and occupancy on the nature of mass transfer between the matrix and the fracture. Counter-current imbibition next to the fracture was observed and quantified, including the influence of formation layering.

  2. Analysis of the Multi-Phase Copying Garbage Collection Algorithm

    SciTech Connect (OSTI)

    Podhorszki, Norbert

    2009-01-01

    The multi-phase copying garbage collection was designed to avoid the need for large amount of reserved memory usually required for the copying types of garbage collection algorithms. The collection is performed in multiple phases using the available free memory. This paper proves that the number of phases depends on the size of the reserved memory and the ratio of the garbage and accessible objects. The performance of the implemented algorithm is tested in a fine-grained parallel Prolog system. We find that reserving only 10% of memory for garbage collection is sufficient for good performance in practice. Additionally, an improvement of the generic algorithm specifically for the tested parallel Prolog system is described.

  3. Reactive facies: An approach for parameterizing field-scale reactive...

    Office of Scientific and Technical Information (OSTI)

    Reactive facies: An approach for parameterizing field-scale reactive transport models using geophysical methods Citation Details In-Document Search Title: Reactive facies: An...

  4. System for reactivating catalysts

    DOE Patents [OSTI]

    Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Anderson, Raymond P. (Idaho Falls, ID)

    2010-03-02

    A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst is provided. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

  5. Multiphase flow modeling based on the hyperbolic thermodynamically compatible systems theory

    SciTech Connect (OSTI)

    Romenski, E.

    2015-03-10

    An application of the theory of thermodynamically compatible hyperbolic systems to design a multiphase compressible flow models is discussed. With the use of such approach the governing equations are derived from the first principles, formulated in a divergent form and can be transformed to a symmetric hyperbolic system in the sense of Friedrichs. A usage of the proposed approach is described for the development of multiphase compressible fluid models, including two-phase flow models.

  6. Multicomponent, multiphase flow in porous media with temperature variation

    SciTech Connect (OSTI)

    Wingard, J.S.; Orr, F.M. Jr.

    1990-10-01

    Recovery of hydrocarbons from porous media is an ongoing concern. Advanced techniques augment conventional recovery methods by injecting fluids that favorably interact with the oil. These fluids interact with the oil by energy transfer, in the case of steam injection, or by mass transfer, as in a miscible gas flood. Often both thermal and compositional considerations are important. An understanding of these injection methods requires knowledge of how temperature variations, phase equilibrium and multiphase flow in porous media interact. The material balance for each component and energy balance are cast as a system of non-strictly hyperbolic partial differential equations. This system of equations is solved using the method of characteristics. The model takes into account the phase behavior by using the Peng-Robinson equation of state to partition the individual components into different phases. Temperature effects are accounted for by the energy balance. Flow effects are modelled by using fractional flow curves and a Stone's three phase relative permeability model. Three problems are discussed. The first problem eliminates the phase behavior aspect of the problem by studying the flow of a single component as it undergoes an isothermal phase change. The second couples the effects of temperature and flow behavior by including a second component that is immiscible with the original component. Phase behavior is added by using a set of three partially miscible components that partition into two or three separate phases. 66 refs., 54 figs., 14 tabs.

  7. Inhibition of slug front corrosion in multiphase flow conditions

    SciTech Connect (OSTI)

    Chen, H.J.; Jepson, W.P.

    1998-12-31

    Corrosion at the slug front at the bottom of a pipeline is identified as one of the worst cases of corrosion occurring in the pipeline which carries unprocessed multiphase production with a high level of CO{sub 2} gas. One objective of the study in recommending a subsea completion to shore was to determine if commercial corrosion inhibitors can control this type of corrosion using carbon steel pipeline. Thus, inhibitors which showed excellent performance in the lab using the Rotating Cylinder Electrode system (RCE) were further evaluated to confirm their performance in a flow loop simulating the test conditions predicted from the flow modeling for the proposed pipeline. The performance profile of two commercial inhibitors were determined in a 4 in. flow loop at 7O C, 100 psig CO{sub 2} partial pressure in corrosive brines with or without ethylene glycol and/or light hydrocarbon. Results showed that the carbon steel pipeline could be adequately protected at low temperature using a commercial corrosion inhibitor to meet the designed life of the pipeline. Ethylene glycol, which is used in the pipeline to prevent hydrate formation, reduces the corrosivity of the brine and gives no effect on inhibitor performance under the slug flow conditions. A good agreement in inhibitor performance was observed between the flow loop and the RCE testing. The uninhibited corrosion rate of the test brine in this study is in good agreement with the predicted value using deWaard and Williams correlation for CO{sub 2} corrosion.

  8. PArallel Reacting Multiphase FLOw Computational Fluid Dynamic Analysis

    Energy Science and Technology Software Center (OSTI)

    2002-06-01

    PARMFLO is a parallel multiphase reacting flow computational fluid dynamics (CFD) code. It can perform steady or unsteady simulations in three space dimensions. It is intended for use in engineering CFD analysis of industrial flow system components. Its parallel processing capabilities allow it to be applied to problems that use at least an order of magnitude more computational cells than the number that can be used on a typical single processor workstation (about 106 cellsmore » in parallel processing mode versus about io cells in serial processing mode). Alternately, by spreading the work of a CFD problem that could be run on a single workstation over a group of computers on a network, it can bring the runtime down by an order of magnitude or more (typically from many days to less than one day). The software was implemented using the industry standard Message-Passing Interface (MPI) and domain decomposition in one spatial direction. The phases of a flow problem may include an ideal gas mixture with an arbitrary number of chemical species, and dispersed droplet and particle phases. Regions of porous media may also be included within the domain. The porous media may be packed beds, foams, or monolith catalyst supports. With these features, the code is especially suited to analysis of mixing of reactants in the inlet chamber of catalytic reactors coupled to computation of product yields that result from the flow of the mixture through the catalyst coaled support structure.« less

  9. Some Specific CASL Requirements for Advanced Multiphase Flow Simulation of Light Water Reactors

    SciTech Connect (OSTI)

    R. A. Berry

    2010-11-01

    Because of the diversity of physical phenomena occuring in boiling, flashing, and bubble collapse, and of the length and time scales of LWR systems, it is imperative that the models have the following features: • Both vapor and liquid phases (and noncondensible phases, if present) must be treated as compressible. • Models must be mathematically and numerically well-posed. • The models methodology must be multi-scale. A fundamental derivation of the multiphase governing equation system, that should be used as a basis for advanced multiphase modeling in LWR coolant systems, is given in the Appendix using the ensemble averaging method. The remainder of this work focuses specifically on the compressible, well-posed, and multi-scale requirements of advanced simulation methods for these LWR coolant systems, because without these are the most fundamental aspects, without which widespread advancement cannot be claimed. Because of the expense of developing multiple special-purpose codes and the inherent inability to couple information from the multiple, separate length- and time-scales, efforts within CASL should be focused toward development of a multi-scale approaches to solve those multiphase flow problems relevant to LWR design and safety analysis. Efforts should be aimed at developing well-designed unified physical/mathematical and high-resolution numerical models for compressible, all-speed multiphase flows spanning: (1) Well-posed general mixture level (true multiphase) models for fast transient situations and safety analysis, (2) DNS (Direct Numerical Simulation)-like models to resolve interface level phenmena like flashing and boiling flows, and critical heat flux determination (necessarily including conjugate heat transfer), and (3) Multi-scale methods to resolve both (1) and (2) automatically, depending upon specified mesh resolution, and to couple different flow models (single-phase, multiphase with several velocities and pressures, multiphase with single velocity and pressure, etc.) A unified, multi-scale approach is advocated to extend the necessary foundations and build the capability to simultaneously solve the fluid dynamic interface problems (interface resolution) as well as multiphase mixtures (homogenization).

  10. Thermodynamic approach to the stability of multi-phase systems. Application

    Office of Scientific and Technical Information (OSTI)

    to the Y2O3-Fe system (Journal Article) | DOE PAGES Thermodynamic approach to the stability of multi-phase systems. Application to the Y2O3-Fe system This content will become publicly available on July 7, 2016 « Prev Next » Title: Thermodynamic approach to the stability of multi-phase systems. Application to the Y2O3-Fe system Oxide-metal systems (OMSs) are important in many practical applications, and therefore, are under extensive studies using a wide range of techniques. The most

  11. Finite Element Heat & Mass Transfer Code

    Energy Science and Technology Software Center (OSTI)

    1996-10-10

    FEHM is a numerical simulation code for subsurface transport processes. It models 3-D, time-dependent, multiphase, multicomponent, non-isothermal, reactive flow through porous and fractured media. It can accurately represent complex 3-D geologic media and structures and their effects on subsurface flow and transport. Its capabilities include flow of gas, water, and heat; flow of air, water, and heat; multiple chemically reactive and sorbing tracers; finite element/finite volume formulation; coupled stress module; saturated and unsaturated media; andmore »double porosity and double porosity/double permeability capabilities.« less

  12. Finite Element Heat & Mass Transfer Code

    Energy Science and Technology Software Center (OSTI)

    1996-10-10

    FEHM is a numerical simulation code for subsurface transport processes. It models 3-D, time-dependent, multiphase, multicomponent, non-isothermal, reactive flow through porous and fractured media. It can accurately represent complex 3-D geologic media and structures and their effects on subsurface flow and transport. Its capabilities include flow of gas, water, and heat; flow of air, water, and heat; multiple chemically reactive and sorbing tracers; finite element/finite volume formulation; coupled stress module; saturated and unsaturated media; andmore » double porosity and double porosity/double permeability capabilities.« less

  13. Multiphase boosting: A growing technology for the challenge of economical deepwater developments

    SciTech Connect (OSTI)

    Colombi, P.; Chiesa, G.; Aggradi, G.F.

    1996-12-31

    The current operating success in the subsea prototype testing and the level of development of different pump concepts are promoting multiphase boosting as a reliable technology for the exploitation of subsea fields. From a situation where very basic questions were asked about the expected performance and reliability of this equipment the Industry is now looking at those scenarios showing the greatest potential for the application of this technology like the deep waters. Competitive options to develop subsea fields, however, may be available and, although they may present some disadvantages compared with multiphase boosting, they make use of traditional practices and proven technologies. In the above perspective, the field operational experience plays a key role to prove the suitability of the proposed systems in handling the untreated well fluids under real subsea conditions so giving multiphase boosting a distinct edge over more conventional solutions. To this end, the paper reviews the main results obtained so far by the underwater testing campaign of a prototype multiphase boosting unit at the Agip Prezioso Field, offshore Sicily. In particular, the review addresses the main technological issues encountered during the subsea operation of the boosting unit together with an initial characterization of the experienced unit performance. The above is considered to provide a significant contribution to the evaluation of the current level of maturity of this technology as well as of the present technological gap to meet the requirements posed by real industrial applications, particularly in deep waters.

  14. Reactive Power Compensator.

    DOE Patents [OSTI]

    El-Sharkawi, M.A.; Venkata, S.S.; Chen, M.; Andexler, G.; Huang, T.

    1992-07-28

    A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation. 26 figs.

  15. Reactive power compensator

    DOE Patents [OSTI]

    El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Woodinville, WA); Chen, Mingliang (Kirkland, WA); Andexler, George (Everett, WA); Huang, Tony (Seattle, WA)

    1992-01-01

    A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

  16. Methods, systems and apparatus for approximation of peak summed fundamental and third harmonic voltages in a multi-phase machine

    DOE Patents [OSTI]

    Ransom, Ray M. (Big Bear City, CA); Gallegos-Lopez, Gabriel (Torrance, CA); Kinoshita, Michael H. (Redondo Beach, CA)

    2012-07-31

    Methods, system and apparatus are provided for quickly approximating a peak summed magnitude (A) of a phase voltage (Vph) waveform in a multi-phase system that implements third harmonic injection.

  17. Reactive power compensating system

    DOE Patents [OSTI]

    Williams, Timothy J. (Redondo Beach, CA); El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Seattle, WA)

    1987-01-01

    The reactive power of an induction machine is compensated by providing fixed capacitors on each phase line for the minimum compensation required, sensing the current on one line at the time its voltage crosses zero to determine the actual compensation required for each phase, and selecting switched capacitors on each line to provide the balance of the compensation required.

  18. Reactive Power Compensating System.

    DOE Patents [OSTI]

    Williams, Timothy J.; El-Sharkawi, Mohamed A.; Venkata, Subrahmanyam S.

    1985-01-04

    The circuit was designed for the specific application of wind-driven induction generators. It has great potential for application in any situation where a varying reactive power load is present, such as with induction motors or generators, or for transmission network compensation.

  19. Isothermal Multiphase Flash Calculations with the PC-SAFT Equation of State

    SciTech Connect (OSTI)

    Justo-Garcia, Daimler N.; Garcia-Sanchez, Fernando; Romero-Martinez, Ascencion

    2008-03-05

    A computational approach for isothermal multiphase flash calculations with the PC-SAFT (Perturbed-Chain Statistical Associating Fluid Theory) equation of state is presented. In the framework of the study of fluid phase equilibria of multicomponent systems, the general multiphase problem is the single most important calculation which consists of finding the correct number and types of phases and their corresponding equilibrium compositions such that the Gibbs energy of the system is a minimum. For solving this problem, the system Gibbs energy was minimized using a rigorous method for thermodynamic stability analysis to find the most stable state of the system. The efficiency and reliability of the approach to predict and calculate complex phase equilibria are illustrated by solving three typical problems encountered in the petroleum industry.

  20. Sand transport and deposition in horizontal multiphase trunklines of subsea satellite developments

    SciTech Connect (OSTI)

    Oudeman, P. )

    1993-11-01

    Gravel packing is unattractive as a way to protect against the effects of sand production in subsea wells because it involves additional completion costs, loss of productivity, and difficulties in subsequent recompletion/well servicing operations. On the other hand, omitting gravel packs means that subsea developments must be designed and operated so that they can tolerate sand production. An experimental study was carried out on sand transport and deposition in multiphase flow in modeled subsea flowlines to address the problem and sand collection in horizontal trunklines, which could lead to reduced line throughput, pigging problems, enhanced pipe-bottom erosion, or even blockage. This study led to the definition of a new model for sand transport in multiphase flow, which was used to establish the risk of sand deposition in trunklines connecting a subsea development to nearby production platform.

  1. Compressible, multiphase semi-implicit method with moment of fluid interface representation

    SciTech Connect (OSTI)

    Jemison, Matthew; Sussman, Mark; Arienti, Marco

    2014-09-16

    A unified method for simulating multiphase flows using an exactly mass, momentum, and energy conserving Cell-Integrated Semi-Lagrangian advection algorithm is presented. The deforming material boundaries are represented using the moment-of-fluid method. Our new algorithm uses a semi-implicit pressure update scheme that asymptotically preserves the standard incompressible pressure projection method in the limit of infinite sound speed. The asymptotically preserving attribute makes the new method applicable to compressible and incompressible flows including stiff materials; enabling large time steps characteristic of incompressible flow algorithms rather than the small time steps required by explicit methods. Moreover, shocks are captured and material discontinuities are tracked, without the aid of any approximate or exact Riemann solvers. As a result, wimulations of underwater explosions and fluid jetting in one, two, and three dimensions are presented which illustrate the effectiveness of the new algorithm at efficiently computing multiphase flows containing shock waves and material discontinuities with large “impedance mismatch.”

  2. Computational study of the shock driven instability of a multiphase particle-gas system

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

    None, None

    2016-02-01

    This paper considers the interaction of a shock wave with a multiphase particle-gas system which creates an instability somewhat similar to the Richtmyer-Meshkov instability but with a larger parameter space. Because this parameter space is large, we only present an introductory survey of the effects of many of these parameters. We highlight the effects of particle-gas coupling, incident shock strength, particle size, effective system density differences, and multiple particle relaxation time effects. We focus on dilute flows with mass loading up to 40% and do not attempt to cover all parametric combinations. Instead, we vary one parameter at a timemore » leaving additional parametric combinations for future work. The simulations are run with the Ares code, developed at Lawrence Livermore National Laboratory, which uses a multiphase particulate transport method to model two-way momentum and energy coupling. A brief validation of these models is presented and coupling effects are explored. It is shown that even for small particles, on the order of 1μm, multi-phase coupling effects are important and diminish the circulation deposition on the interface by up to 25%. These coupling effects are shown to create large temperature deviations from the dusty gas approximation, up to 20% greater, especially at higher shock strengths. It is also found that for a multiphase instability, the vortex sheet deposited at the interface separates into two sheets. In conclusion, depending on the particle and particle-gas Atwood numbers, the instability may be suppressed or enhanced by the interactions of these two vortex sheets.« less

  3. Considerations for developing models of multiphase flow in deformable porous media.

    SciTech Connect (OSTI)

    Martinez, Mario J.; Stone, Charles Michael

    2008-09-01

    This document summarizes research and planning for the development of a numerical simulation capability for nonisothermal multiphase, multicomponent transport in heterogeneous deformable porous materials. Particular attention is given to describing a mathematical formulation for flow in deformable media and for numerical techniques for dealing with phase transitions. A development plan is formulated to provide a computational capability motivated by current and future needs in geosystems management for energy security.

  4. Reactive facies: An approach for parameterizing field-scale reactive

    Office of Scientific and Technical Information (OSTI)

    transport models using geophysical methods (Journal Article) | SciTech Connect Reactive facies: An approach for parameterizing field-scale reactive transport models using geophysical methods Citation Details In-Document Search Title: Reactive facies: An approach for parameterizing field-scale reactive transport models using geophysical methods Authors: Sassen, D. ; Hubbard, S. S. ; Bea, S. ; Spycher, N. ; Chen, J. ; Spycher, N. ; Denham, M. Publication Date: 2012-05-01 OSTI Identifier:

  5. Reactive Air Aluminization

    SciTech Connect (OSTI)

    Choi, Jung-Pyung; Chou, Y. S.; Stevenson, Jeffry W.

    2011-10-28

    Ferritic stainless steels and other alloys are of great interest to SOFC developers for applications such as interconnects, cell frames, and balance of plant components. While these alloys offer significant advantages (e.g., low material and manufacturing cost, high thermal conductivity, and high temperature oxidation resistance), there are challenges which can hinder their utilization in SOFC systems; these challenges include Cr volatility and reactivity with glass seals. To overcome these challenges, protective coatings and surface treatments for the alloys are under development. In particular, aluminization of alloy surfaces offers the potential for mitigating both evaporation of Cr from the alloy surface and reaction of alloy constituents with glass seals. Commercial aluminization processes are available to SOFC developers, but they tend to be costly due to their use of exotic raw materials and/or processing conditions. As an alternative, PNNL has developed Reactive Air Aluminization (RAA), which offers a low-cost, simpler alternative to conventional aluminization methods.

  6. Permeable Reactive Barriers | Department of Energy

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

    Permeable Reactive Barriers Permeable Reactive Barriers Permeable Reactive Barrier Field Projects Durango, Colorado Durango, Colorado DOE installed a PRB in October 1995 to treat ...

  7. TOUGHREACT-Pitzer V1.21

    Energy Science and Technology Software Center (OSTI)

    2011-12-01

    TOUGHREACT is a numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media. The program is written in Fortran 77 and was developed by introducing reactive chemistry into the multiphase flow code TOUGH2 V2. Interactions between mineral assemblages and fluids can occur under local equilibrium or kinetic rates. The gas phase can be chemically active. Precipitation and dissolution reactions can change formation porosity and permeability, and can also modifymore » the unsaturated flow properties of the rock. The code is distributed with a comprehensive user?s guide that includes sample problems addressing geothermal reservoirs and hydrothermal systems, nuclear waste isolation, groundwater quality, sequestration of carbon dioxide in saline aquifers, and supergene copper enrichment.« less

  8. TOUGH2: A general-purpose numerical simulator for multiphase nonisothermal flows

    SciTech Connect (OSTI)

    Pruess, K. [Lawrence Berkeley Lab., CA (United States)

    1991-06-01

    Numerical simulators for multiphase fluid and heat flows in permeable media have been under development at Lawrence Berkeley Laboratory for more than 10 yr. Real geofluids contain noncondensible gases and dissolved solids in addition to water, and the desire to model such `compositional` systems led to the development of a flexible multicomponent, multiphase simulation architecture known as MULKOM. The design of MULKOM was based on the recognition that the mass-and energy-balance equations for multiphase fluid and heat flows in multicomponent systems have the same mathematical form, regardless of the number and nature of fluid components and phases present. Application of MULKOM to different fluid mixtures, such as water and air, or water, oil, and gas, is possible by means of appropriate `equation-of-state` (EOS) modules, which provide all thermophysical and transport parameters of the fluid mixture and the permeable medium as a function of a suitable set of primary thermodynamic variables. Investigations of thermal and hydrologic effects from emplacement of heat-generating nuclear wastes into partially water-saturated formations prompted the development and release of a specialized version of MULKOM for nonisothermal flow of water and air, named TOUGH. TOUGH is an acronym for `transport of unsaturated groundwater and heat` and is also an allusion to the tuff formations at Yucca Mountain, Nevada. The TOUGH2 code is intended to supersede TOUGH. It offers all the capabilities of TOUGH and includes a considerably more general subset of MULKOM modules with added capabilities. The paper briefly describes the simulation methodology and user features.

  9. Sampling device for withdrawing a representative sample from single and multi-phase flows

    DOE Patents [OSTI]

    Apley, Walter J. (Pasco, WA); Cliff, William C. (Richland, WA); Creer, James M. (Richland, WA)

    1984-01-01

    A fluid stream sampling device has been developed for the purpose of obtaining a representative sample from a single or multi-phase fluid flow. This objective is carried out by means of a probe which may be inserted into the fluid stream. Individual samples are withdrawn from the fluid flow by sampling ports with particular spacings, and the sampling parts are coupled to various analytical systems for characterization of the physical, thermal, and chemical properties of the fluid flow as a whole and also individually.

  10. Low Cost Non-Reactive

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

    Prepared: 10/28/09 Low Cost Non-Reactive Coating for Refractory Metals A non-reactive coating for refractory metals has been developed at The Ames Laboratory. Contamination of rare earth and reactive metals and their alloys has been a chronic problem that results from their interaction with the crucibles or other vessels used in high temperature processing or during other applications. As a consequence, processing and other costs are high due to the need to replace equipment or containers, or

  11. Chemically and compositionally modified solid solution disordered multiphase nickel hydroxide positive electrode for alkaline rechargeable electrochemical cells

    DOE Patents [OSTI]

    Ovshinsky, Stanford R. (Bloomfield Hills, MI); Corrigan, Dennis (Troy, MI); Venkatesan, Srini (Southfield, MI); Young, Rosa (Troy, MI); Fierro, Christian (Troy, MI); Fetcenko, Michael A. (Rochester Hills, MI)

    1994-01-01

    A high capacity, long cycle life positive electrode for use in an alkaline rechargeable electrochemical cell comprising: a solid solution nickel hydroxide material having a multiphase structure that comprises at least one polycrystalline .gamma.-phase including a polycrystalline .gamma.-phase unit cell comprising spacedly disposed plates with at least one chemical modifier incorporated around the plates, the plates having a range of stable intersheet distances corresponding to a 2.sup.+ oxidation state and a 3.5.sup.+, or greater, oxidation state; and at least one compositional modifier incorporated into the solid solution nickel hydroxide material to promote the multiphase structure.

  12. L3:THM.CFD.P9.05 Milestone Report Single/Multiphase CFD Assessment, Verification,

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

    Milestone Report Single/Multiphase CFD Assessment, Verification, and Validation Yidong Xia and Hong Luo North Carolina State University September 30, 2014 CASL-8-2014-0210-000 CASL-U-2014-0210-000 L3:THM.CFD.P9.05 Single/Multiphase CFD assessment, verification, and validation L3:THM.CFD.P9.05 milestone report Yidong Xia and Hong Luo Department of Mechanical and Aerospace Engineering North Carolina State University, Raleigh, NC, 27695, USA CASL-U-2014-0210-000 L3:THM.CFD.P9.05 On the performance

  13. Multi-Phase CFD Modeling of Solid Sorbent Carbon Capture System

    SciTech Connect (OSTI)

    Ryan, Emily M.; DeCroix, David; Breault, Ronald W.; Xu, Wei; Huckaby, E. D.; Saha, Kringan; Darteville, Sebastien; Sun, Xin

    2013-07-30

    Computational fluid dynamics (CFD) simulations are used to investigate a low temperature post-combustion carbon capture reactor. The CFD models are based on a small scale solid sorbent carbon capture reactor design from ADA-ES and Southern Company. The reactor is a fluidized bed design based on a silica-supported amine sorbent. CFD models using both Eulerian-Eulerian and Eulerian-Lagrangian multi-phase modeling methods are developed to investigate the hydrodynamics and adsorption of carbon dioxide in the reactor. Models developed in both FLUENT® and BARRACUDA are presented to explore the strengths and weaknesses of state of the art CFD codes for modeling multi-phase carbon capture reactors. The results of the simulations show that the FLUENT® Eulerian-Lagrangian simulations (DDPM) are unstable for the given reactor design; while the BARRACUDA Eulerian-Lagrangian model is able to simulate the system given appropriate simplifying assumptions. FLUENT® Eulerian-Eulerian simulations also provide a stable solution for the carbon capture reactor given the appropriate simplifying assumptions.

  14. Multi-phase CFD modeling of solid sorbent carbon capture system

    SciTech Connect (OSTI)

    Ryan, E. M.; DeCroix, D.; Breault, Ronald W.; Xu, W.; Huckaby, E. David

    2013-01-01

    Computational fluid dynamics (CFD) simulations are used to investigate a low temperature post-combustion carbon capture reactor. The CFD models are based on a small scale solid sorbent carbon capture reactor design from ADA-ES and Southern Company. The reactor is a fluidized bed design based on a silica-supported amine sorbent. CFD models using both Eulerian–Eulerian and Eulerian–Lagrangian multi-phase modeling methods are developed to investigate the hydrodynamics and adsorption of carbon dioxide in the reactor. Models developed in both FLUENT® and BARRACUDA are presented to explore the strengths and weaknesses of state of the art CFD codes for modeling multi-phase carbon capture reactors. The results of the simulations show that the FLUENT® Eulerian–Lagrangian simulations (DDPM) are unstable for the given reactor design; while the BARRACUDA Eulerian–Lagrangian model is able to simulate the system given appropriate simplifying assumptions. FLUENT® Eulerian–Eulerian simulations also provide a stable solution for the carbon capture reactor given the appropriate simplifying assumptions.

  15. Compressible, multiphase semi-implicit method with moment of fluid interface representation

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

    Jemison, Matthew; Sussman, Mark; Arienti, Marco

    2014-09-16

    A unified method for simulating multiphase flows using an exactly mass, momentum, and energy conserving Cell-Integrated Semi-Lagrangian advection algorithm is presented. The deforming material boundaries are represented using the moment-of-fluid method. Our new algorithm uses a semi-implicit pressure update scheme that asymptotically preserves the standard incompressible pressure projection method in the limit of infinite sound speed. The asymptotically preserving attribute makes the new method applicable to compressible and incompressible flows including stiff materials; enabling large time steps characteristic of incompressible flow algorithms rather than the small time steps required by explicit methods. Moreover, shocks are captured and material discontinuities aremore » tracked, without the aid of any approximate or exact Riemann solvers. As a result, wimulations of underwater explosions and fluid jetting in one, two, and three dimensions are presented which illustrate the effectiveness of the new algorithm at efficiently computing multiphase flows containing shock waves and material discontinuities with large “impedance mismatch.”« less

  16. Mechanism-based Representative Volume Elements (RVEs) for Predicting Property Degradations in Multiphase Materials

    SciTech Connect (OSTI)

    Xu, Wei; Sun, Xin; Li, Dongsheng; Ryu, Seun; Khaleel, Mohammad A.

    2013-02-01

    Quantitative understanding of the evolving thermal-mechanical properties of a multi-phase material hinges upon the availability of quantitative statistically representative microstructure descriptions. Questions then arise as to whether a two-dimensional (2D) or a three-dimensional (3D) representative volume element (RVE) should be considered as the statistically representative microstructure. Although 3D models are more representative than 2D models in general, they are usually computationally expensive and difficult to be reconstructed. In this paper, we evaluate the accuracy of a 2D RVE in predicting the property degradations induced by different degradation mechanisms with the multiphase solid oxide fuel cell (SOFC) anode material as an example. Both 2D and 3D microstructure RVEs of the anodes are adopted to quantify the effects of two different degradation mechanisms: humidity-induced electrochemical degradation and phosphorus poisoning induced structural degradation. The predictions of the 2D model are then compared with the available experimental measurements and the results from the 3D model. It is found that the 2D model, limited by its inability of reproducing the realistic electrical percolation, is unable to accurately predict the degradation of thermo-electrical properties. On the other hand, for the phosphorus poisoning induced structural degradation, both 2D and 3D microstructures yield similar results, indicating that the 2D model is capable of providing computationally efficient yet accurate results for studying the structural degradation within the anodes.

  17. Practical aspects and uncertainty analysis of biological effective dose (BED) regarding its three-dimensional calculation in multiphase radiotherapy treatment plans

    SciTech Connect (OSTI)

    Kauweloa, Kevin I. Gutierrez, Alonso N.; Bergamo, Angelo; Stathakis, Sotirios; Papanikolaou, Nikos; Mavroidis, Panayiotis

    2014-07-15

    Purpose: There is a growing interest in the radiation oncology community to use the biological effective dose (BED) rather than the physical dose (PD) in treatment plan evaluation and optimization due to its stronger correlation with radiobiological effects. Radiotherapy patients may receive treatments involving a single only phase or multiple phases (e.g., primary and boost). Since most treatment planning systems cannot calculate the analytical BED distribution in multiphase treatments, an approximate multiphase BED expression, which is based on the total physical dose distribution, has been used. The purpose of this paper is to reveal the mathematical properties of the approximate BED formulation, relative to the true BED. Methods: The mathematical properties of the approximate multiphase BED equation are analyzed and evaluated. In order to better understand the accuracy of the approximate multiphase BED equation, the true multiphase BED equation was derived and the mathematical differences between the true and approximate multiphase BED equations were determined. The magnitude of its inaccuracies under common clinical circumstances was also studied. All calculations were performed on a voxel-by-voxel basis using the three-dimensional dose matrices. Results: Results showed that the approximate multiphase BED equation is accurate only when the dose-per-fractions (DPFs) in both the first and second phases are equal, which occur when the dose distribution does not significantly change between the phases. In the case of heterogeneous dose distributions, which significantly vary between the phases, there are fewer occurrences of equal DPFs and hence the inaccuracy of the approximate multiphase BED is greater. These characteristics are usually seen in the dose distributions being delivered to organs at risk rather than to targets. Conclusions: The finding of this study indicates that the true multiphase BED equation should be implemented in the treatment planning systems due to the inconsistent accuracy of the approximate multiphase BED equation in most of the clinical situations.

  18. A Tariff for Reactive Power

    SciTech Connect (OSTI)

    Kueck, John D; Kirby, Brendan J; Li, Fangxing; Tufon, Christopher; Isemonger, Alan

    2008-07-01

    Two kinds of power are required to operate an electric power system: real power, measured in watts, and reactive power, measured in volt-amperes reactive or VARs. Reactive power supply is one of a class of power system reliability services collectively known as ancillary services, and is essential for the reliable operation of the bulk power system. Reactive power flows when current leads or lags behind voltage. Typically, the current in a distribution system lags behind voltage because of inductive loads such as motors. Reactive power flow wastes energy and capacity and causes voltage droop. To correct lagging power flow, leading reactive power (current leading voltage) is supplied to bring the current into phase with voltage. When the current is in phase with voltage, there is a reduction in system losses, an increase in system capacity, and a rise in voltage. Reactive power can be supplied from either static or dynamic VAR sources. Static sources are typically transmission and distribution equipment, such as capacitors at substations, and their cost has historically been included in the revenue requirement of the transmission operator (TO), and recovered through cost-of-service rates. By contrast, dynamic sources are typically generators capable of producing variable levels of reactive power by automatically controlling the generator to regulate voltage. Transmission system devices such as synchronous condensers can also provide dynamic reactive power. A class of solid state devices (called flexible AC transmission system devices or FACTs) can provide dynamic reactive power. One specific device has the unfortunate name of static VAR compensator (SVC), where 'static' refers to the solid state nature of the device (it does not include rotating equipment) and not to the production of static reactive power. Dynamic sources at the distribution level, while more costly would be very useful in helping to regulate local voltage. Local voltage regulation would reduce system losses, increase circuit capacity, increase reliability, and improve efficiency. Reactive power is theoretically available from any inverter-based equipment such as photovoltaic (PV) systems, fuel cells, microturbines, and adjustable-speed drives. However, the installation is usually only economical if reactive power supply is considered during the design and construction phase. In this report, we find that if the inverters of PV systems or the generators of combined heat and power (CHP) systems were designed with capability to supply dynamic reactive power, they could do this quite economically. In fact, on an annualized basis, these inverters and generators may be able to supply dynamic reactive power for about $5 or $6 per kVAR. The savings from the local supply of dynamic reactive power would be in reduced losses, increased capacity, and decreased transmission congestion. The net savings are estimated to be about $7 per kVAR on an annualized basis for a hypothetical circuit. Thus the distribution company could economically purchase a dynamic reactive power service from customers for perhaps $6/kVAR. This practice would provide for better voltage regulation in the distribution system and would provide an alternate revenue source to help amortize the cost of PV and CHP installations. As distribution and transmission systems are operated under rising levels of stress, the value of local dynamic reactive supply is expected to grow. Also, large power inverters, in the range of 500 kW to 1 MW, are expected to decrease in cost as they become mass produced. This report provides one data point which shows that the local supply of dynamic reactive power is marginally profitable at present for a hypothetical circuit. We expect that the trends of growing power flow on the existing system and mass production of inverters for distributed energy devices will make the dynamic supply of reactive power from customers an integral component of economical and reliable system operation in the future.

  19. AOI 1— COMPUTATIONAL ENERGY SCIENCES:MULTIPHASE FLOW RESEARCH High-fidelity multi-phase radiation module for modern coal combustion systems

    SciTech Connect (OSTI)

    Modest, Michael

    2013-11-15

    The effects of radiation in particle-laden flows were the object of the present research. The presence of particles increases optical thickness substantially, making the use of the “optically thin” approximation in most cases a very poor assumption. However, since radiation fluxes peak at intermediate optical thicknesses, overall radiative effects may not necessarily be stronger than in gas combustion. Also, the spectral behavior of particle radiation properties is much more benign, making spectral models simpler (and making the assumption of a gray radiator halfway acceptable, at least for fluidized beds when gas radiation is not large). On the other hand, particles scatter radiation, making the radiative transfer equation (RTE) much more di#14;fficult to solve. The research carried out in this project encompassed three general areas: (i) assessment of relevant radiation properties of particle clouds encountered in fluidized bed and pulverized coal combustors, (ii) development of proper spectral models for gas–particulate mixtures for various types of two-phase combustion flows, and (iii) development of a Radiative Transfer Equation (RTE) solution module for such applications. The resulting models were validated against artificial cases since open literature experimental data were not available. The final models are in modular form tailored toward maximum portability, and were incorporated into two research codes: (i) the open-source CFD code OpenFOAM, which we have extensively used in our previous work, and (ii) the open-source multi-phase flow code MFIX, which is maintained by NETL.

  20. Integrated acoustic phase separator and multiphase fluid composition monitoring apparatus and method

    DOE Patents [OSTI]

    Sinha, Dipen N

    2014-02-04

    An apparatus and method for down hole gas separation from the multiphase fluid flowing in a wellbore or a pipe, for determining the quantities of the individual components of the liquid and the flow rate of the liquid, and for remixing the component parts of the fluid after which the gas volume may be measured, without affecting the flow stream, are described. Acoustic radiation force is employed to separate gas from the liquid, thereby permitting measurements to be separately made for these two components; the liquid (oil/water) composition is determined from ultrasonic resonances; and the gas volume is determined from capacitance measurements. Since the fluid flows around and through the component parts of the apparatus, there is little pressure difference, and no protection is required from high pressure differentials.

  1. Progress in the Development of Compressible, Multiphase Flow Modeling Capability for Nuclear Reactor Flow Applications

    SciTech Connect (OSTI)

    R. A. Berry; R. Saurel; F. Petitpas; E. Daniel; O. Le Metayer; S. Gavrilyuk; N. Dovetta

    2008-10-01

    In nuclear reactor safety and optimization there are key issues that rely on in-depth understanding of basic two-phase flow phenomena with heat and mass transfer. Within the context of multiphase flows, two bubble-dynamic phenomena – boiling (heterogeneous) and flashing or cavitation (homogeneous boiling), with bubble collapse, are technologically very important to nuclear reactor systems. The main difference between boiling and flashing is that bubble growth (and collapse) in boiling is inhibited by limitations on the heat transfer at the interface, whereas bubble growth (and collapse) in flashing is limited primarily by inertial effects in the surrounding liquid. The flashing process tends to be far more explosive (and implosive), and is more violent and damaging (at least in the near term) than the bubble dynamics of boiling. However, other problematic phenomena, such as crud deposition, appear to be intimately connecting with the boiling process. In reality, these two processes share many details.

  2. Ultrasonic tomography for in-process measurements of temperature in a multi-phase medium

    DOE Patents [OSTI]

    Beller, L.S.

    1993-01-26

    A method and apparatus are described for the in-process measurement of internal particulate temperature utilizing ultrasonic tomography techniques to determine the speed of sound through a specimen material. Ultrasonic pulses are transmitted through a material, which can be a multi-phase material, over known flight paths and the ultrasonic pulse transit times through all sectors of the specimen are measured to determine the speed of sound. The speed of sound being a function of temperature, it is possible to establish the correlation between speed of sound and temperature, throughout a cross-section of the material, which correlation is programmed into a computer to provide for a continuous in-process measurement of temperature throughout the specimen.

  3. Ultrasonic tomography for in-process measurements of temperature in a multi-phase medium

    DOE Patents [OSTI]

    Beller, Laurence S.

    1993-01-01

    A method and apparatus for the in-process measurement of internal particulate temperature utilizing ultrasonic tomography techniques to determine the speed of sound through a specimen material. Ultrasonic pulses are transmitted through a material, which can be a multi-phase material, over known flight paths and the ultrasonic pulse transit times through all sectors of the specimen are measured to determine the speed of sound. The speed of sound being a function of temperature, it is possible to establish the correlation between speed of sound and temperature, throughout a cross-section of the material, which correlation is programmed into a computer to provide for a continuous in-process measurement of temperature throughout the specimen.

  4. Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

    SciTech Connect (OSTI)

    Yortsos, Y.C.

    2001-05-29

    This report is an investigation of various multi-phase and multiscale transport and reaction processes associated with heavy oil recovery. The thrust areas of the project include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.

  5. Numerical Investigation of Vertical Plunging Jet Using a Hybrid Multifluid–VOF Multiphase CFD Solver

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

    Shonibare, Olabanji Y.; Wardle, Kent E.

    2015-01-01

    A novel hybrid multiphase flow solver has been used to conduct simulations of a vertical plunging liquid jet. This solver combines a multifluid methodology with selective interface sharpening to enable simulation of both the initial jet impingement and the long-time entrained bubble plume phenomena. Models are implemented for variable bubble size capturing and dynamic switching of interface sharpened regions to capture transitions between the initially fully segregated flow types into the dispersed bubbly flow regime. It was found that the solver was able to capture the salient features of the flow phenomena under study and areas for quantitative improvement havemore » been explored and identified. In particular, a population balance approach is employed and detailed calibration of the underlying models with experimental data is required to enable quantitative prediction of bubble size and distribution to capture the transition between segregated and dispersed flow types with greater fidelity.« less

  6. Method and system for measuring multiphase flow using multiple pressure differentials

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2001-01-01

    An improved method and system for measuring a multiphase flow in a pressure flow meter. An extended throat venturi is used and pressure of the multiphase flow is measured at three or more positions in the venturi, which define two or more pressure differentials in the flow conduit. The differential pressures are then used to calculate the mass flow of the gas phase, the total mass flow, and the liquid phase. The method for determining the mass flow of the high void fraction fluid flow and the gas flow includes certain steps. The first step is calculating a gas density for the gas flow. The next two steps are finding a normalized gas mass flow rate through the venturi and computing a gas mass flow rate. The following step is estimating the gas velocity in the venturi tube throat. The next step is calculating the pressure drop experienced by the gas-phase due to work performed by the gas phase in accelerating the liquid phase between the upstream pressure measuring point and the pressure measuring point in the venturi throat. Another step is estimating the liquid velocity in the venturi throat using the calculated pressure drop experienced by the gas-phase due to work performed by the gas phase. Then the friction is computed between the liquid phase and a wall in the venturi tube. Finally, the total mass flow rate based on measured pressure in the venturi throat is calculated, and the mass flow rate of the liquid phase is calculated from the difference of the total mass flow rate and the gas mass flow rate.

  7. Liquid-based gating mechanism with tunable multiphase selectivity and antifouling behaviour

    SciTech Connect (OSTI)

    Hou, Xu; Hu, Yuhang; Grinthal, Alison; Khan, Mughees; Aizenberg, Joanna

    2015-03-04

    Living organisms make extensive use of micro- and nanometre-sized pores as gatekeepers for controlling the movement of fluids, vapours and solids between complex environments. In addition, the ability of such pores to coordinate multiphase transport, in a highly selective and subtly triggered fashion and without clogging, has inspired interest in synthetic gated pores for applications ranging from fluid processing to 3D printing and lab-on-chip systems1-10.But although specific gating and transport behaviours have been realized by precisely tailoring pore surface chemistries and pore geometries6,11–17, a single system capable of controlling complex, selective multiphase transport has remained a distant prospect, and fouling is nearly inevitable.Here we introduce a gating mechanism that uses a capillary-stabilized liquid as a reversible, reconfigurable gate that fills and seals pores in the closed state, and creates a non-fouling, liquid-lined pore in the open state.Theoretical modelling and experiments demonstrate that for each transport substance, the gating threshold—the pressure needed to open the pores—can be rationally tuned over a wide pressure range. This enables us to realize in one system differential response profiles for a variety of liquids and gases, even letting liquids flow through the pore while preventing gas from escaping.These capabilities allow us to dynamically modulate gas–liquid sorting in a microfluidic flow and to separate a three-phase air water–oil mixture, with the liquid lining ensuring sustained antifouling behaviour. Because the liquid gating strategy enables efficient long-term operation and can be applied to a variety of pore structures and membrane materials, and to micro- as well as macroscale fluid systems, we expect it to prove useful in a wide range of applications.

  8. DENSE MULTIPHASE FLOW SIMULATION: CONTINUUM MODEL FOR POLY-DISPERSED SYSTEMS USING KINETIC THEORY

    SciTech Connect (OSTI)

    Moses Bogere

    2011-08-31

    The overall objective of the project was to verify the applicability of the FCMOM approach to the kinetic equations describing the particle flow dynamics. For monodispersed systems the fundamental equation governing the particle flow dynamics is the Boltzmann equation. During the project, the FCMOM was successfully applied to several homogeneous and in-homogeneous problems in different flow regimes, demonstrating that the FCMOM has the potential to be used to solve efficiently the Boltzmann equation. However, some relevant issues still need to be resolved, i.e. the homogeneous cooling problem (inelastic particles cases) and the transition between different regimes. In this report, the results obtained in homogeneous conditions are discussed first. Then a discussion of the validation results for in-homogeneous conditions is provided. And finally, a discussion will be provided about the transition between different regimes. Alongside the work on development of FCMOM approach studies were undertaken in order to provide insights into anisotropy or particles kinetics in riser hydrodynamics. This report includes results of studies of multiphase flow with unequal granular temperatures and analysis of momentum re-distribution in risers due to particle-particle and fluid-particle interactions. The study of multiphase flow with unequal granular temperatures entailed both simulation and experimental studies of two particles sizes in a riser and, a brief discussion of what was accomplished will be provided. And finally, a discussion of the analysis done on momentum re-distribution of gas-particles flow in risers will be provided. In particular a discussion of the remaining work needed in order to improve accuracy and predictability of riser hydrodynamics based on two-fluid models and how they can be used to model segregation in risers.

  9. Multi-Phased, Post-Accident Support of the Fukushima Dai-Ichi Nuclear Power Plant - 12246

    SciTech Connect (OSTI)

    Gay, Arnaud; Gillet, Philippe; Ytournel, Bertrand; Varet, Thierry; David, Laurent; Prevost, Thierry; Redonnet, Carol; Piot, Gregoire; Jouaville, Stephane; Pagis, Georges

    2012-07-01

    In the wake of the March 11 earthquake and tsunami and the subsequent flooding of several of the Fukushima Dai-Ichi reactors, Japan and the Japanese utility TEPCO faced a crisis situation with incredible challenges: substantial amounts of radioactive mixed seawater and freshwater accumulated in the basements of four reactor and other buildings on the site. This water held varying levels of contamination due to the fact that it had been in contact with damaged fuel elements in the cores and with other contaminated components. The overall water inventory was estimated at around 110,000 tons of water with contamination levels up to the order of 1 Ci/l. Time was of the essence to avoid overflow of this accumulated water into the ocean. AREVA proposed, designed and implemented a water treatment solution using a proven chemical coprecipitation process with ppFeNi reagent, which is currently in use for effluent treatment on several nuclear sites including AREVA sites. In addition to the extremely short schedule the other challenge was to adapt the chemical treatment process to the expected composition of the Fukushima water and, in particular, to evaluate the impact of salinity on process performance. It was also necessary to define operating conditions for the VEOLIA equipment that had been selected for implementation of the process in the future facility. The operation phase began on June 17, and by the end of July more than 30,000 tons of highly radioactive saltwater had been decontaminated - the Decontamination Factor (DF) for Cesium was ∼10{sup 4}. It allowed recycling the contaminated water to cool the reactors while protecting workers and the environment. This paper focuses on the Actiflo{sup TM}-Rad water treatment unit project that was part of the TEPCO general water treatment scheme. It presents a detailed look at the principles of the Actiflo{sup TM}-Rad, related on-the-fly R and D, an explanation of system implementation challenges, and a brief summary of operation results to date. AREVA's response to the Fukushima Dai-Ichi crisis was multi-phased: emergency aid and relief supply was sent within days after the accident; AREVA-Veolia engineering teams designed and implemented a water treatment solution in record time, only 3 months; and AREVA continues to support TEPCO and propose solutions for waste management, soil remediation and decontamination of the Fukushima Dai-Ichi site. Despite the huge challenges, the Actiflo{sup TM}-Rad project has been a success: the water treatment unit started on time and performed as expected. The performance is the result of many key elements: AREVA expertise in radioactive effluents decontamination, Veolia know-how in water treatment equipments in crisis environment, and of course AREVA and Veolia teams' creativity. The project success is also due to AREVA and Veolia teams' reactivity and high level of commitment with engineering teams working 24/7 in Japan, France and Germany. AREVA and Veolia deep knowledge of the Japanese industry ensured that the multi-cultural exchanges were not an issue. Finally the excellent overall project management and execution by TEPCO and other Japanese stakeholders was very efficient. The emergency water treatment was a key step of the roadmap towards restoration from the accident at Fukushima Dai-Ichi that TEPCO designed and keeps executing with success. (authors)

  10. FINAL PROJECT REPORT DOE Early Career Principal Investigator Program Project Title: Developing New Mathematical Models for Multiphase Flows Based on a Fundamental Probability Density Function Approach

    SciTech Connect (OSTI)

    Shankar Subramaniam

    2009-04-01

    This final project report summarizes progress made towards the objectives described in the proposal entitled “Developing New Mathematical Models for Multiphase Flows Based on a Fundamental Probability Density Function Approach”. Substantial progress has been made in theory, modeling and numerical simulation of turbulent multiphase flows. The consistent mathematical framework based on probability density functions is described. New models are proposed for turbulent particle-laden flows and sprays.

  11. Multiphase flow simulations of a moving fluidized bed regenerator in a carbon capture unit

    SciTech Connect (OSTI)

    Sarkar, Avik; Pan, Wenxiao; Suh, Dong-Myung; Huckaby, E. D.; Sun, Xin

    2014-10-01

    To accelerate the commercialization and deployment of carbon capture technologies, computational fluid dynamics (CFD)-based tools may be used to model and analyze the performance of carbon capture devices. This work presents multiphase CFD-based flow simulations for the regeneration device responsible for extracting CO2 from CO2-loaded sorbent particles before the particles are recycled. The use of solid particle sorbents in this design is a departure from previously reported systems, where aqueous sorbents are employed. Another new feature is the inclusion of a series of perforated plates along the regenerator height. The influence of these plates on sorbent distribution is examined for varying sorbent holdup, fluidizing gas velocity, and particle size. The residence time distribution of sorbents is also measured to classify the low regime as plug flow or well-mixed flow. The purpose of this work is to better understand the sorbent flow characteristics before reaction kinetics of CO2 desorption can be implemented.

  12. Parameter estimation from flowing fluid temperature logging data in unsaturated fractured rock using multiphase inverse modeling

    SciTech Connect (OSTI)

    Mukhopadhyay, S.; Tsang, Y.; Finsterle, S.

    2009-01-15

    A simple conceptual model has been recently developed for analyzing pressure and temperature data from flowing fluid temperature logging (FFTL) in unsaturated fractured rock. Using this conceptual model, we developed an analytical solution for FFTL pressure response, and a semianalytical solution for FFTL temperature response. We also proposed a method for estimating fracture permeability from FFTL temperature data. The conceptual model was based on some simplifying assumptions, particularly that a single-phase airflow model was used. In this paper, we develop a more comprehensive numerical model of multiphase flow and heat transfer associated with FFTL. Using this numerical model, we perform a number of forward simulations to determine the parameters that have the strongest influence on the pressure and temperature response from FFTL. We then use the iTOUGH2 optimization code to estimate these most sensitive parameters through inverse modeling and to quantify the uncertainties associated with these estimated parameters. We conclude that FFTL can be utilized to determine permeability, porosity, and thermal conductivity of the fracture rock. Two other parameters, which are not properties of the fractured rock, have strong influence on FFTL response. These are pressure and temperature in the borehole that were at equilibrium with the fractured rock formation at the beginning of FFTL. We illustrate how these parameters can also be estimated from FFTL data.

  13. Application of a geocentrifuge and sterolithographically fabricated apertures to multiphase flow in complex fracture apertures.

    SciTech Connect (OSTI)

    Glenn E. McCreery; Robert D. Stedtfeld; Alan T. Stadler; Daphne L. Stoner; Paul Meakin

    2005-09-01

    A geotechnical centrifuge was used to investigate unsaturated multiphase fluid flow in synthetic fracture apertures under a variety of flow conditions. The geocentrifuge subjected the fluids to centrifugal forces allowing the Bond number to be systematically changed without adjusting the fracture aperture of the fluids. The fracture models were based on the concept that surfaces generated by the fracture of brittle geomaterials have a self-affine fractal geometry. The synthetic fracture surfaces were fabricated from a transparent epoxy photopolymer using sterolithography, and fluid flow through the transparent fracture models was monitored by an optical image acquisition system. Aperture widths were chosen to be representative of the wide range of geological fractures in the vesicular basalt that lies beneath the Idaho Nation Laboratory (INL). Transitions between different flow regimes were observed as the acceleration was changed under constant flow conditions. The experiments showed the transition between straight and meandering rivulets in smooth walled apertures (aperture width = 0.508 mm), the dependence of the rivulet width on acceleration in rough walled fracture apertures (average aperture width = 0.25 mm), unstable meandering flow in rough walled apertures at high acceleration (20g) and the narrowing of the wetted region with increasing acceleration during the penetration of water into an aperture filled with wetted particles (0.875 mm diameter glass spheres).

  14. Engine combustion control via fuel reactivity stratification

    DOE Patents [OSTI]

    Reitz, Rolf Deneys; Hanson, Reed M.; Splitter, Derek A.; Kokjohn, Sage L.

    2015-07-14

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  15. Engine combustion control via fuel reactivity stratification

    DOE Patents [OSTI]

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2013-12-31

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  16. Dynamic modeling of injection-induced fault reactivation and ground motion and impact on surface structures and human perception

    SciTech Connect (OSTI)

    Rutqvist, Jonny; Cappa, Frederic; Rinaldi, Antonio P.; Godano, Maxime

    2014-12-31

    We summarize recent modeling studies of injection-induced fault reactivation, seismicity, and its potential impact on surface structures and nuisance to the local human population. We used coupled multiphase fluid flow and geomechanical numerical modeling, dynamic wave propagation modeling, seismology theories, and empirical vibration criteria from mining and construction industries. We first simulated injection-induced fault reactivation, including dynamic fault slip, seismic source, wave propagation, and ground vibrations. From co-seismic average shear displacement and rupture area, we determined the moment magnitude to about Mw = 3 for an injection-induced fault reactivation at a depth of about 1000 m. We then analyzed the ground vibration results in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and frequency content, with comparison to the U.S. Bureau of Mines’ vibration criteria for cosmetic damage to buildings, as well as human-perception vibration limits. For the considered synthetic Mw = 3 event, our analysis showed that the short duration, high frequency ground motion may not cause any significant damage to surface structures, and would not cause, in this particular case, upward CO2 leakage, but would certainly be felt by the local population.

  17. Dynamic modeling of injection-induced fault reactivation and ground motion and impact on surface structures and human perception

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

    Rutqvist, Jonny; Cappa, Frederic; Rinaldi, Antonio P.; Godano, Maxime

    2014-12-31

    We summarize recent modeling studies of injection-induced fault reactivation, seismicity, and its potential impact on surface structures and nuisance to the local human population. We used coupled multiphase fluid flow and geomechanical numerical modeling, dynamic wave propagation modeling, seismology theories, and empirical vibration criteria from mining and construction industries. We first simulated injection-induced fault reactivation, including dynamic fault slip, seismic source, wave propagation, and ground vibrations. From co-seismic average shear displacement and rupture area, we determined the moment magnitude to about Mw = 3 for an injection-induced fault reactivation at a depth of about 1000 m. We then analyzed themore » ground vibration results in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and frequency content, with comparison to the U.S. Bureau of Mines’ vibration criteria for cosmetic damage to buildings, as well as human-perception vibration limits. For the considered synthetic Mw = 3 event, our analysis showed that the short duration, high frequency ground motion may not cause any significant damage to surface structures, and would not cause, in this particular case, upward CO2 leakage, but would certainly be felt by the local population.« less

  18. Reactive composite compositions and mat barriers

    DOE Patents [OSTI]

    Langton, Christine A. (Aiken, SC); Narasimhan, Rajendran (Evans, GA); Karraker, David G. (Aiken, SC)

    2001-01-01

    A hazardous material storage area has a reactive multi-layer composite mat which lines an opening into which a reactive backfill and hazardous material are placed. A water-inhibiting cap may cover the hazardous material storage area. The reactive multi-layer composite mat has a backing onto which is placed an active layer which will neutralize or stabilize hazardous waste and a fronting layer so that the active layer is between the fronting and backing layers. The reactive backfill has a reactive agent which can stabilize or neutralize hazardous material and inhibit the movement of the hazardous material through the hazardous material storage area.

  19. Numerical Study of Coal Gasification Using Eulerian-Eulerian Multiphase Model

    SciTech Connect (OSTI)

    Shi, S.; Guenther, C.; Orsino, S.

    2007-09-01

    Gasification converts the carbon-containing material into a synthesis gas (syngas) which can be used as a fuel to generate electricity or used as a basic chemical building block for a large number of uses in the petrochemical and refining industries. Based on the mode of conveyance of the fuel and the gasifying medium, gasification can be classified into fixed or moving bed, fluidized bed, and entrained flow reactors. Entrained flow gasifiers normally feature dilute flow with small particle size and can be successfully modeled with the Discrete Phase Method (DPM). For the other types, the Eulerian-Eulerian (E-E) or the so called two-fluid multiphase model is a more appropriate approach. The E-E model treats the solid phase as a distinct interpenetrating granular “fluid” and it is the most general-purposed multi-fluid model. This approach provides transient, three-dimensional, detailed information inside the reactor which would otherwise be unobtainable through experiments due to the large scale, high pressure and/or temperature. In this paper, a transient, three-dimensional model of the Power Systems Development Facility (PSDF) transport gasifier will be presented to illustrate how Computational Fluid Dynamics (CFD) can be used for large-scale complicated geometry with detailed physics and chemistry. In the model, eleven species are included in the gas phase while four pseudo-species are assumed in the solid phase. A total of sixteen reactions, both homogeneous (involving only gas phase species) and heterogeneous (involving species in both gas and solid phases), are used to model the coal gasification chemistry. Computational results have been validated against PSDF experimental data from lignite to bituminous coals under both air and oxygen blown conditions. The PSDF gasifier geometry was meshed with about 70,000, hexahedra-dominated cells. A total of six cases with different coal, feed gas, and/or operation conditions have been performed. The predicted and measured temperature profiles along the gasifier and gas compositions at the outlet agreed fairly well.

  20. Effect of wettability on scale-up of multiphase flow from core-scale to reservoir fine-grid-scale

    SciTech Connect (OSTI)

    Chang, Y.C.; Mani, V.; Mohanty, K.K.

    1997-08-01

    Typical field simulation grid-blocks are internally heterogeneous. The objective of this work is to study how the wettability of the rock affects its scale-up of multiphase flow properties from core-scale to fine-grid reservoir simulation scale ({approximately} 10{prime} x 10{prime} x 5{prime}). Reservoir models need another level of upscaling to coarse-grid simulation scale, which is not addressed here. Heterogeneity is modeled here as a correlated random field parameterized in terms of its variance and two-point variogram. Variogram models of both finite (spherical) and infinite (fractal) correlation length are included as special cases. Local core-scale porosity, permeability, capillary pressure function, relative permeability functions, and initial water saturation are assumed to be correlated. Water injection is simulated and effective flow properties and flow equations are calculated. For strongly water-wet media, capillarity has a stabilizing/homogenizing effect on multiphase flow. For small variance in permeability, and for small correlation length, effective relative permeability can be described by capillary equilibrium models. At higher variance and moderate correlation length, the average flow can be described by a dynamic relative permeability. As the oil wettability increases, the capillary stabilizing effect decreases and the deviation from this average flow increases. For fractal fields with large variance in permeability, effective relative permeability is not adequate in describing the flow.

  1. Incorporation of Reaction Kinetics into a Multiphase, Hydrodynamic Model of a Fischer Tropsch Slurry Bubble Column Reactor

    SciTech Connect (OSTI)

    Donna Guillen, PhD; Anastasia Gribik; Daniel Ginosar, PhD; Steven P. Antal, PhD

    2008-11-01

    This paper describes the development of a computational multiphase fluid dynamics (CMFD) model of the Fischer Tropsch (FT) process in a Slurry Bubble Column Reactor (SBCR). The CMFD model is fundamentally based which allows it to be applied to different industrial processes and reactor geometries. The NPHASE CMFD solver [1] is used as the robust computational platform. Results from the CMFD model include gas distribution, species concentration profiles, and local temperatures within the SBCR. This type of model can provide valuable information for process design, operations and troubleshooting of FT plants. An ensemble-averaged, turbulent, multi-fluid solution algorithm for the multiphase, reacting flow with heat transfer was employed. Mechanistic models applicable to churn turbulent flow have been developed to provide a fundamentally based closure set for the equations. In this four-field model formulation, two of the fields are used to track the gas phase (i.e., small spherical and large slug/cap bubbles), and the other two fields are used for the liquid and catalyst particles. Reaction kinetics for a cobalt catalyst is based upon values reported in the published literature. An initial, reaction kinetics model has been developed and exercised to demonstrate viability of the overall solution scheme. The model will continue to be developed with improved physics added in stages.

  2. Layered reactive particles with controlled geometries, energies, and reactivities, and methods for making the same

    DOE Patents [OSTI]

    Fritz, Gregory M; Knepper, Robert Allen; Weihs, Timothy P; Gash, Alexander E; Sze, John S

    2013-04-30

    An energetic composite having a plurality of reactive particles each having a reactive multilayer construction formed by successively depositing reactive layers on a rod-shaped substrate having a longitudinal axis, dividing the reactive-layer-deposited rod-shaped substrate into a plurality of substantially uniform longitudinal segments, and removing the rod-shaped substrate from the longitudinal segments, so that the reactive particles have a controlled, substantially uniform, cylindrically curved or otherwise rod-contoured geometry which facilitates handling and improves its packing fraction, while the reactant multilayer construction controls the stability, reactivity and energy density of the energetic composite.

  3. Permeable Reactive Barriers | Department of Energy

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

    Permeable Reactive Barriers Permeable Reactive Barriers Permeable Reactive Barrier Field Projects Durango, Colorado Durango, Colorado DOE installed a PRB in October 1995 to treat ground water from a uranium mill tailings disposal site at Durango, Colorado Read more Cañon City, Colorado Cañon City, Colorado ESL personnel conduct tests and help evaluate performance at other PRB sites, such as Cotter Corporation's Cañon City site in Colorado. Read more Monticello, Utah Monticello, Utah

  4. Shock Desensitization Experiments and Reactive Flow Modeling...

    Office of Scientific and Technical Information (OSTI)

    Shock Desensitization Experiments and Reactive Flow Modeling on Self-Sustaining LX-17 Detonation Waves Citation Details In-Document Search Title: Shock Desensitization Experiments ...

  5. Rejuvenating Permeable Reactive Barriers by Chemical Flushing

    Broader source: Energy.gov [DOE]

    Final Report:Rejuvenating Permeable Reactive Barriers by Chemical Flushing,U.S. Environmental Protection Agency, Region 8 Support.August 2004

  6. Interfacial Structure and Reactivity | Argonne National Laboratory

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

    a robust, molecular-scale understanding of its structure and reactivity? Research Context The transport of ions across the electrodeelectrolyte interface can lead to kinetic...

  7. Method for reactivating catalysts and a method for recycling supercritical fluids used to reactivate the catalysts

    DOE Patents [OSTI]

    Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Anderson, Raymond P. (Idaho Falls, ID)

    2008-08-05

    A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

  8. Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend

    DOE Patents [OSTI]

    Ortiz, Marcos German (Idaho Falls, ID)

    1998-01-01

    A system for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow.

  9. Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend

    DOE Patents [OSTI]

    Ortiz, M.G.

    1998-02-10

    A system is described for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.

  10. General Reactive Atomistic Simulation Program

    Energy Science and Technology Software Center (OSTI)

    2004-09-22

    GRASP (General Reactive Atomistic Simulation Program) is primarily intended as a molecular dynamics package for complex force fields, The code is designed to provide good performance for large systems, either in parallel or serial execution mode, The primary purpose of the code is to realistically represent the structural and dynamic properties of large number of atoms on timescales ranging from picoseconds up to a microsecond. Typically the atoms form a representative sample of some material,more » such as an interface between polycrystalline silicon and amorphous silica. GRASP differs from other parallel molecular dynamics codes primarily due to it’s ability to handle relatively complicated interaction potentials and it’s ability to use more than one interaction potential in a single simulation. Most of the computational effort goes into the calculation of interatomic forces, which depend in a complicated way on the positions of all the atoms. The forces are used to integrate the equations of motion forward in time using the so-called velocity Verlet integration scheme. Alternatively, the forces can be used to find a minimum energy configuration, in which case a modified steepest descent algorithm is used.« less

  11. Experimental determination of the speciation, partitioning, and release of perrhenate as a chemical surrogate for pertechnetate from a sodalite-bearing multiphase ceramic waste form

    SciTech Connect (OSTI)

    Pierce, Eric M.; Lukens, Wayne W.; Fitts, Jeff. P.; Jantzen, Carol. M.; Tang, G.

    2013-12-01

    A key component to closing the nuclear fuel cycle is the storage and disposition of nuclear waste in geologic systems. Multiphase ceramic waste forms have been studied extensively as a potential host matrix for nuclear waste. Understanding the speciation, partitioning, and release behavior of radionuclides immobilized in multiphase ceramic waste forms is a critical aspect of developing the scientific and technical basis for nuclear waste management. In this study, we evaluated a sodalite-bearing multiphase ceramic waste form (i.e., fluidized-bed steam reform sodium aluminosilicate [FBSR NAS] product) as a potential host matrix for long-lived radionuclides, such as technetium (99Tc). The FBSR NAS material consists primarily of nepheline (ideally NaAlSiO4), anion-bearing sodalites (ideally M8[Al6Si6O24]X2, where M refers to alkali and alkaline earth cations and X refers to monovalent anions), and nosean (ideally Na8[AlSiO4]6SO4). Bulk X-ray absorption fine structure analysis of the multiphase ceramic waste form, suggest rhenium (Re) is in the Re(VII) oxidation state and has partitioned to a Re-bearing sodalite phase (most likely a perrhenate sodalite Na8[Al6Si6O24](ReO4)2). Rhenium was added as a chemical surrogate for 99Tc during the FBSR NAS synthesis process. The weathering behavior of the FBSR NAS material was evaluated under hydraulically unsaturated conditions with deionized water at 90 ?C. The steady-state Al, Na, and Si concentrations suggests the weathering mechanisms are consistent with what has been observed for other aluminosilicate minerals and include a combination of ion exchange, network hydrolysis, and the formation of an enriched-silica surface layer or phase. The steady-state S and Re concentrations are within an order of magnitude of the nosean and perrhenate sodalite solubility, respectively. The order of magnitude difference between the observed and predicted concentration for Re and S may be associated with the fact that the anion-bearing sodalites contained in the multiphase ceramic matrix are present as mixed-anion sodalite phases. These results suggest the multiphase FBSR NAS material may be a viable host matrix for long-lived, highly mobilie radionuclides which is a critical aspect in the management of nuclear waste.

  12. Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah |

    Office of Environmental Management (EM)

    Department of Energy Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah PDF icon Gamma Survey of a Permeable Reactive Barrier at Monticello, Utah More Documents & Publications Third (March 2006) Coring and Analysis of Zero-Valent Iron Permeable Reactive Barrier, Monticello, Utah Hydraulic Conductivity of the Monticello Permeable Reactive Barrier

  13. Reactivity control assembly for nuclear reactor

    DOE Patents [OSTI]

    Bollinger, Lawrence R. (Schenectady, NY)

    1984-01-01

    Reactivity control assembly for nuclear reactor comprises supports stacked above reactor core for holding control rods. Couplers associated with the supports and a vertically movable drive shaft have lugs at their lower ends for engagement with the supports.

  14. Groundwater well with reactive filter pack

    DOE Patents [OSTI]

    Gilmore, T.J.; Holdren, G.R. Jr.; Kaplan, D.I.

    1998-09-08

    A method and apparatus are disclosed for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques. 3 figs.

  15. Groundwater well with reactive filter pack

    DOE Patents [OSTI]

    Gilmore, Tyler J.; Holdren, Jr., George R.; Kaplan, Daniel I.

    1998-01-01

    A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

  16. Characterization of Dual-Fuel Reactivity Controlled Compression...

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

    Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel Characterization of Dual-Fuel Reactivity Controlled Compression Ignition (RCCI)...

  17. Light-Duty Reactivity Controlled Compression Ignition Drive Cycle...

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

    Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel Economy and Emissions Estimates Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel ...

  18. Reactivity of Ozone with Solid Potassium Iodide Investigated...

    Office of Scientific and Technical Information (OSTI)

    Reactivity of Ozone with Solid Potassium Iodide Investigated by Atomic Force Microscopy Citation Details In-Document Search Title: Reactivity of Ozone with Solid Potassium...

  19. Dual FIB-SEM 3D imaging and lattice boltzmann modeling of porosimetry and multiphase flow in chalk.

    SciTech Connect (OSTI)

    Rinehart, Alex; Petrusak, Robin (Advanced Resources International, Inc., Arlington, VA); Heath, Jason E.; Dewers, Thomas A.; Yoon, Hongkyu

    2010-12-01

    Mercury intrusion porosimetry (MIP) is an often-applied technique for determining pore throat distributions and seal analysis of fine-grained rocks. Due to closure effects, potential pore collapse, and complex pore network topologies, MIP data interpretation can be ambiguous, and often biased toward smaller pores in the distribution. We apply 3D imaging techniques and lattice-Boltzmann modeling in interpreting MIP data for samples of the Cretaceous Selma Group Chalk. In the Mississippi Interior Salt Basin, the Selma Chalk is the apparent seal for oil and gas fields in the underlying Eutaw Fm., and, where unfractured, the Selma Chalk is one of the regional-scale seals identified by the Southeast Regional Carbon Sequestration Partnership for CO2 injection sites. Dual focused ion - scanning electron beam and laser scanning confocal microscopy methods are used for 3D imaging of nanometer-to-micron scale microcrack and pore distributions in the Selma Chalk. A combination of image analysis software is used to obtain geometric pore body and throat distributions and other topological properties, which are compared to MIP results. 3D data sets of pore-microfracture networks are used in Lattice Boltzmann simulations of drainage (wetting fluid displaced by non-wetting fluid via the Shan-Chen algorithm), which in turn are used to model MIP procedures. Results are used in interpreting MIP results, understanding microfracture-matrix interaction during multiphase flow, and seal analysis for underground CO2 storage.

  20. A mixture model for shock compression of porous multi-component reactive materials

    SciTech Connect (OSTI)

    Baer, M.R.

    1993-07-01

    A multiphase mixture model is presented to describe shock compression of highly porous, multi-component powders. Volume fractions are represented as independent kinematic variables and thermodynamically-admissible phase interaction constitutive models are formulated in the context of a three phase system. Numerical solutions of the multiphase flow equations simulated impact on a porous layer of mixed powders of Al and Fe{sub 2}O{sub 3}. The multiphase model predicts dispersive compaction waves which have features similar to observed time-resolved pressure measurements.

  1. Water reactive hydrogen fuel cell power system

    DOE Patents [OSTI]

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-11-25

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into the fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  2. Water reactive hydrogen fuel cell power system

    DOE Patents [OSTI]

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  3. REDUCING UNCERTAINTIES IN MODEL PREDICTIONS VIA HISTORY MATCHING OF CO2 MIGRATION AND REACTIVE TRANSPORT MODELING OF CO2 FATE AT THE SLEIPNER PROJECT

    SciTech Connect (OSTI)

    Zhu, Chen

    2015-03-31

    An important question for the Carbon Capture, Storage, and Utility program is “can we adequately predict the CO2 plume migration?” For tracking CO2 plume development, the Sleipner project in the Norwegian North Sea provides more time-lapse seismic monitoring data than any other sites, but significant uncertainties still exist for some of the reservoir parameters. In Part I, we assessed model uncertainties by applying two multi-phase compositional simulators to the Sleipner Benchmark model for the uppermost layer (Layer 9) of the Utsira Sand and calibrated our model against the time-lapsed seismic monitoring data for the site from 1999 to 2010. Approximate match with the observed plume was achieved by introducing lateral permeability anisotropy, adding CH4 into the CO2 stream, and adjusting the reservoir temperatures. Model-predicted gas saturation, CO2 accumulation thickness, and CO2 solubility in brine—none were used as calibration metrics—were all comparable with the interpretations of the seismic data in the literature. In Part II & III, we evaluated the uncertainties of predicted long-term CO2 fate up to 10,000 years, due to uncertain reaction kinetics. Under four scenarios of the kinetic rate laws, the temporal and spatial evolution of CO2 partitioning into the four trapping mechanisms (hydrodynamic/structural, solubility, residual/capillary, and mineral) was simulated with ToughReact, taking into account the CO2-brine-rock reactions and the multi-phase reactive flow and mass transport. Modeling results show that different rate laws for mineral dissolution and precipitation reactions resulted in different predicted amounts of trapped CO2 by carbonate minerals, with scenarios of the conventional linear rate law for feldspar dissolution having twice as much mineral trapping (21% of the injected CO2) as scenarios with a Burch-type or Alekseyev et al.–type rate law for feldspar dissolution (11%). So far, most reactive transport modeling (RTM) studies for CCUS have used the conventional rate law and therefore simulated the upper bound of mineral trapping. However, neglecting the regional flow after injection, as most previous RTM studies have done, artificially limits the extent of geochemical reactions as if it were in a batch system. By replenishing undersaturated groundwater from upstream, the Utsira Sand is reactive over a time scale of 10,000 years. The results from this project have been communicated via five peer-reviewed journal articles, four conference proceeding papers, and 19 invited and contributed presentations at conferences and seminars.

  4. Method For Reactivating Solid Catalysts Used For Alklation Reactions

    DOE Patents [OSTI]

    Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Coates, Kyle (Shelley, ID); Zalewski, David J. (Proctorville, OH); Fox, Robert V. (Idaho Falls, ID)

    2005-05-03

    A method for reactivating a solid alkylation catalyst is provided which can be performed within a reactor that contains the alkylation catalyst or outside the reactor. Effective catalyst reactivation is achieved whether the catalyst is completely deactivated or partially deactivated. A fluid reactivating agent is employed to dissolve catalyst fouling agents and also to react with such agents and carry away the reaction products. The deactivated catalyst is contacted with the fluid reactivating agent under pressure and temperature conditions such that the fluid reactivating agent is dense enough to effectively dissolve the fouling agents and any reaction products of the fouling agents and the reactivating agent. Useful pressures and temperatures for reactivation include near-critical, critical, and supercritical pressures and temperatures for the reactivating agent. The fluid reactivating agent can include, for example, a branched paraffin containing at least one tertiary carbon atom, or a compound that can be isomerized to a molecule containing at least one tertiary carbon atom.

  5. Method for reactivating solid catalysts used in alkylation reactions

    DOE Patents [OSTI]

    Ginosar, Daniel M.; Thompson, David N.; Coates, Kyle; Zalewski, David J.; Fox, Robert V.

    2003-06-17

    A method for reactivating a solid alkylation catalyst is provided which can be performed within a reactor that contains the alkylation catalyst or outside the reactor. Effective catalyst reactivation is achieved whether the catalyst is completely deactivated or partially deactivated. A fluid reactivating agent is employed to dissolve catalyst fouling agents and also to react with such agents and carry away the reaction products. The deactivated catalyst is contacted with the fluid reactivating agent under pressure and temperature conditions such that the fluid reactivating agent is dense enough to effectively dissolve the fouling agents and any reaction products of the fouling agents and the reactivating agent. Useful pressures and temperatures for reactivation include near-critical, critical, and supercritical pressures and temperatures for the reactivating agent. The fluid reactivating agent can include, for example, a branched paraffin containing at least one tertiary carbon atom, or a compound that can be isomerized to a molecule containing at least one tertiary carbon atom.

  6. Neutron Radiography Reactor Reactivity -- Focused Lessons Learned

    SciTech Connect (OSTI)

    Eric Woolstenhulme; Randal Damiana; Kenneth Schreck; Ann Marie Phillips; Dana Hewit

    2010-11-01

    As part of the Global Threat Reduction Initiative, the Neutron Radiography Reactor (NRAD) at the Idaho National Laboratory (INL) was converted from using highly enriched uranium (HEU) to low enriched uranium (LEU) fuel. After the conversion, NRAD resumed operations and is meeting operational requirements. Radiography image quality and the number of images that can be produced in a given time frame match pre-conversion capabilities. However, following the conversion, NRAD’s excess reactivity with the LEU fuel was less than it had been with the HEU fuel. Although some differences between model predictions and actual performance are to be expected, the lack of flexibility in NRAD’s safety documentation prevented adjusting the reactivity by adding more fuel, until the safety documentation could be modified. To aid future reactor conversions, a reactivity-focused Lessons Learned meeting was held. This report summarizes the findings of the lessons learned meeting and addresses specific questions posed by DOE regarding NRAD’s conversion and reactivity.

  7. TOUGHREACT V2

    Energy Science and Technology Software Center (OSTI)

    2011-12-01

    TOUGHREACT is a numerical simulation program for chemically reactive non-isothermal flows of multiphase fluids in porous and fractured media. The program is written in Fortran 77 and was developed by introducing reactive chemistry into the multiphase flow code TOUGH2 V2. Interactions between mineral assemblages and fluids can occur under local equilibrium or kinetic rates. The gas phase can be chemically active. Precipitation and dissolution reactions can change formation porosity and permeability, and can also modifymore » the unsaturated flow properties of the rock. The code is distributed with a comprehensive user?s guide that includes sample problems addressing geothermal reservoirs and hydrothermal systems, nuclear waste isolation, groundwater quality, sequestration of carbon dioxide in saline aquifers, and supergene copper enrichment. The TOUGHREACT V2 package supports the following fluid property modules packaged into TOUGH2 V2.0 (CR-1574): EOS1, EOS2, EOS3, EOS4, EOS7, EOS9, and ECO2N. New features in V2 include multi-site surface complexation and ion exchange, aqueous kinetics, restructuring for faster execution, and more flexible input formats.« less

  8. Non-intrusive, high-resolution, real-time, two-dimensional imaging of multiphase materials using acoustic array sensors

    SciTech Connect (OSTI)

    Cassiède, M.; Shaw, J. M.

    2015-04-15

    Two parallel multi-element ultrasonic acoustic arrays combined with sets of focal laws for acoustic signal generation and a classical tomographic inversion algorithm are used to generate real-time two-dimensional micro seismic acoustic images of multiphase materials. Proof of concept and calibration measurements were performed for single phase and two phase liquids, uniform polyvinyl chloride (PVC) plates, and aluminum cylinders imbedded in PVC plates. Measurement artefacts, arising from the limited range of viewing angles, and the compromise between data acquisition rate and image quality are discussed. The angle range of scanning and the image resolution were varied, and the effects on the quality of the reproduction of the speed of sound profiles of model solids and liquids with known geometries and compositions were analysed in detail. The best image quality results were obtained for a scanning angle range of [−35°, 35°] at a step size of 2.5° post processed to generate images on a 40 μm square grid. The data acquisition time for high quality images with a 30 mm × 40 mm view field is 10 min. Representation of two-phase solids with large differences in speed of sound between phases and where one phase is dispersed in the form of macroscopic objects (greater than 1 mm in diameter) proved to be the most difficult to image accurately. Liquid-liquid and liquid-vapor phase boundaries, in micro porous solids by contrast, were more readily defined. Displacement of air by water and water by heptane in natural porous limestone provides illustrative kinetic examples. Measurement results with these realistic cases demonstrate the feasibility of the technique to monitor in real time and on the micrometer length scale local composition and flow of organic liquids in inorganic porous media, one of many envisioned engineering applications. Improvement of data acquisition rate is an area for future collaborative study.

  9. Reactive Transport and Coupled THM Processes in Engineering Barrier Systems (EBS)

    SciTech Connect (OSTI)

    Steefel, Carl; Rutqvist, Jonny; Tsang, Chin-Fu; Liu, Hui-Hai; Sonnenthal, Eric; Houseworth, Jim; Birkholzer, Jens

    2010-08-31

    Geological repositories for disposal of high-level nuclear wastes generally rely on a multi-barrier system to isolate radioactive wastes from the biosphere. The multi-barrier system typically consists of a natural barrier system, including repository host rock and its surrounding subsurface environment, and an engineering barrier system (EBS). EBS represents the man-made, engineered materials placed within a repository, including the waste form, waste canisters, buffer materials, backfill and seals (OECD, 2003). EBS plays a significant role in the containment and long-term retardation of radionuclide release. EBS is involved in complex thermal, hydrogeological, mechanical, chemical and biological processes, such as heat release due to radionuclide decay, multiphase flow (including gas release due to canister corrosion), swelling of buffer materials, radionuclide diffusive transport, waste dissolution and chemical reactions. All these processes are related to each other. An in-depth understanding of these coupled processes is critical for the performance assessment (PA) for EBS and the entire repository. Within the EBS group of Used Fuel Disposition (UFD) Campaign, LBNL is currently focused on (1) thermal-hydraulic-mechanical-chemical (THMC) processes in buffer materials (bentonite) and (2) diffusive transport in EBS associated with clay host rock, with a long-term goal to develop a full understanding of (and needed modeling capabilities to simulate) impacts of coupled processes on radionuclide transport in different components of EBS, as well as the interaction between near-field host rock (e.g., clay) and EBS and how they effect radionuclide release. This final report documents the progress that LBNL has made in its focus areas. Specifically, Section 2 summarizes progress on literature review for THMC processes and reactive-diffusive radionuclide transport in bentonite. The literature review provides a picture of the state-of-the-art of the relevant research areas addressed by LBNL. Section 3 documents the current modeling tools, available at LBNL, for the EBS study. This may be important for identifying future modeling activities within the EBS group with these current capabilities and needs for future EBS modeling development. Section 4 presents the results of geomechanical modeling using the Barcelona Basic Model (BBM) constitutive relationship for thermo-elasto-plastic media such as bentonite and an update on reactive-diffusive transport modeling approaches through bentonite in the EBS. Section 5 discusses identified knowledge gaps and technical issues as well as short- and long-term R&D plans.

  10. SU-E-T-510: Mathematical Analysis of Approximate Biological Effective Dose (BED) Calculation for Multi-Phase Radiotherapy Treatment Plans

    SciTech Connect (OSTI)

    Kauweloa, K; Gutierrez, A; Bergamo, A; Stathakis, S; Papanikolaou, N; Mavroidis, P

    2014-06-01

    Purpose: There is growing interest about biological effective dose (BED) and its application in treatment plan evaluation due to its stronger correlation with treatment outcome. An approximate biological effective dose (BEDA) equation was introduced to simplify BED calculations by treatment planning systems in multi-phase treatments. The purpose of this work is to reveal its mathematical properties relative to the true, multi-phase BED (BEDT) equation. Methods: The BEDT equation was derived and used to reveal the mathematical properties of BEDA. MATLAB (MathWorks, Natick, MA) was used to simulate and analyze common and extreme clinical multi-phase cases. In those cases, percent error (Perror) and Bland-Altman analysis were used to study the significance of the inaccuracies of BEDA for different combinations of total doses, numbers of fractions, doses per fractions and ? over ? values. All the calculations were performed on a voxel-basis in order to study how dose distributions would affect the accuracy of BEDA. Results: When the voxel dose-per-fractions (DPF) delivered by both phases are equal, BEDA and BEDT are equal. In heterogeneous dose distributions, which significantly vary between the phases, there are fewer occurrences of equal DPFs and hence the imprecision of BEDA is greater. It was shown that as the ? over ? ratio increased the accuracy of BEDA would improve. Examining twenty-four cases, it was shown that the range of DPF ratios for a 3 Perror varied from 0.32 to 7.50Gy, whereas for Perror of 1 the range varied from 0.50 to 2.96Gy. Conclusion: The DPF between the different phases should be equal in order to render BEDA accurate. OARs typically receive heterogeneous dose distributions hence the probability of equal DPFs is low. Consequently, the BEDA equation should only be used for targets or OARs that receive uniform or very similar dose distributions by the different treatment phases.

  11. Reactivity control assembly for nuclear reactor. [LMFBR

    DOE Patents [OSTI]

    Bollinger, L.R.

    1982-03-17

    This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

  12. Nuclear reactivity control using laser induced polarization

    DOE Patents [OSTI]

    Bowman, Charles D. (Los Alamos, NM)

    1991-01-01

    A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neutrons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

  13. Nuclear reactivity control using laser induced polarization

    DOE Patents [OSTI]

    Bowman, Charles D. (Los Alamos, NM)

    1990-01-01

    A control element for reactivity control of a fission source provides an atomic density of .sup.3 He in a control volume which is effective to control criticality as the .sup.3 He is spin-polarized. Spin-polarization of the .sup.3 He affects the cross section of the control volume for fission neturons and hence, the reactivity. An irradiation source is directed within the .sup.3 He for spin-polarizing the .sup.3 He. An alkali-metal vapor may be included with the .sup.3 He where a laser spin-polarizes the alkali-metal atoms which in turn, spin-couple with .sup.3 He to spin-polarize the .sup.3 He atoms.

  14. Microstructure, Phase Formation, and Stress of Reactively-Deposited Metal

    Office of Scientific and Technical Information (OSTI)

    Hydride Thin Films (Technical Report) | SciTech Connect Microstructure, Phase Formation, and Stress of Reactively-Deposited Metal Hydride Thin Films Citation Details In-Document Search Title: Microstructure, Phase Formation, and Stress of Reactively-Deposited Metal Hydride Thin Films This document summarizes research of reactively deposited metal hydride thin films and their properties. Reactive deposition processes are of interest, because desired stoichiometric phases are created in a

  15. Characterization of Dual-Fuel Reactivity Controlled Compression Ignition

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

    (RCCI) Using Hydrated Ethanol and Diesel Fuel | Department of Energy Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel Characterization of Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel This study uses numerical simulations to explore the use of wet ethanol as the low-reactivity fuel and diesel as the high-reactivity fuel for RCCI operation in a heavy-duty diesel engine. PDF icon

  16. Hydraulic Conductivity of the Monticello Permeable Reactive Barrier

    Office of Environmental Management (EM)

    November 2005 Update | Department of Energy Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update PDF icon Hydraulic Conductivity of the Monticello Permeable Reactive Barrier November 2005 Update More Documents & Publications Variation in Hydraulic Conductivity Over Time at the

  17. DEVELOPMENT OF A COMPUTATIONAL MULTIPHASE FLOW MODEL FOR FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

    SciTech Connect (OSTI)

    Donna Post Guillen; Tami Grimmett; Anastasia M. Gribik; Steven P. Antal

    2010-09-01

    The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The model includes heat generation due to the exothermic chemical reaction, as well as heat removal from a constant temperature heat exchanger. Results of the CMFD simulations (similar to those shown in Figure 1) will be presented.

  18. DOE - Office of Legacy Management -- Reactive Metals Inc - OH 10

    Office of Legacy Management (LM)

    Reactive Metals Inc - OH 10 FUSRAP Considered Sites Site: Reactive Metals Inc. (OH.10) Designated Name: Alternate Name: Location: Evaluation Year: Site Operations: Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: Also see Ashtabula Site Documents Related to Reactive Metals Inc

  19. Determining conductivity and mobility values of individual components in multiphase composite Cu{sub 1.97}Ag{sub 0.03}Se

    SciTech Connect (OSTI)

    Day, Tristan W.; Brown, David R.; Snyder, G. Jeffrey; Zeier, Wolfgang G.; Melot, Brent C.

    2014-10-27

    The intense interest in phase segregation in thermoelectrics as a means to reduce the lattice thermal conductivity and to modify the electronic properties from nanoscale size effects has not been met with a method for separately measuring the properties of each phase assuming a classical mixture. Here, we apply effective medium theory for measurements of the in-line and Hall resistivity of a multiphase composite, in this case Cu{sub 1.97}Ag{sub 0.03}Se. The behavior of these properties with magnetic field as analyzed by effective medium theory allows us to separate the conductivity and charge carrier mobility of each phase. This powerful technique can be used to determine the matrix properties in the presence of an unwanted impurity phase, to control each phase in an engineered composite, and to determine the maximum carrier concentration change by a given dopant, making it the first step toward a full optimization of a multiphase thermoelectric material and distinguishing nanoscale effects from those of a classical mixture.

  20. Multiphase Dissolution Model

    Energy Science and Technology Software Center (OSTI)

    1999-06-08

    This program simulates the leaching behavior of glass-ceramic monoliths or particles immersed in liquids. The monoliths or particles may be composed of up to 10 separate compounds, each with different densities and forward leach rate constants. Each compound in turn can be composed of up to 10 species (elements, oxides, etc.). A data file is used to store the physical information about the compounds, i.e., density, forward rate constant and the percentages of each speciesmore » making up each compound. Once the program has input the data file and the user has setup the experimental parameters, the program begins a calculation loop for each time interval, :{Delta}t [days]. The time interval is calculated by dividing the duration of the experiment by the number of data points desired by the user. The program can simulate static conditions as would be the case for a standard leach test or under flowing water conditions which might be found in nature. It can also account for precipitation out of solution for various compounds, if the precipitation coefficients are known. An output data file is created showing the amount of each species in solution as a function of time. An accompanying program, LDATA, is used to create and manage data files for input into the MDM program. The files contain physical data about the compounds, and species making up the material.« less

  1. iTOUGH2 Command Reference

    SciTech Connect (OSTI)

    Finsterle, Stefan

    2002-06-18

    iTOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media. This report contains a detailed description of all iTOUGH2 commands.

  2. T2WELL/ECO2N

    Energy Science and Technology Software Center (OSTI)

    002966IBMPC00 T2Well/ECO2N Version 1.0: Multiphase and Non-Isothermal Model for Coupled Wellbore-Reservoir Flow of Carbon Dioxide and Variable Salinity Water  http:..esd.lbl.gov/tough/licensing.html 

  3. Preparation of reactive beta-dicalcium silicate

    DOE Patents [OSTI]

    Shen, Ming-Shing (Laramie, WY, NJ); Chen, James M. (Rahway, NJ); Yang, Ralph T. (Amherst, NY)

    1982-01-01

    This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane and hydrogen, at a temperature of about 850.degree.-1000.degree. C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

  4. Fossil power plant layup and reactivation

    SciTech Connect (OSTI)

    Tsou, J.L.

    1996-07-01

    In recent years, many utilities have developed excess generation capacity problems during period of low system load growth, particularly with new generation units coming on-line. System load studies may indicate that the situation is temporary and higher generation capacity will be needed in the near future. The objective of layup is to prevent component deterioration during the long shut down periods. This paper discusses equipment preservation practices in use in the industry and the advantages/disadvantages of various layup methods. Other issues related to plant layup and reactivation are also presented.

  5. Preparation of reactive beta-dicalcium silicate

    DOE Patents [OSTI]

    Shen, M.S.; Chen, J.M.; Yang, R.T.

    1980-02-28

    This invention relates to the preparation of fine particles of reactive beta-dicalcium silicate by means of a solid state process which comprises firing a mixture of calcium sulfate, silica, and a reducing additive selected from the group consisting of calcium sulfide, carbon, carbon monoxide, methane, and hydrogen, at a temperature of about 850 to 1000/sup 0/C. A carrier gas such as nitrogen or carbon dioxide may also be added, if desired. A high concentration of sulfur dioxide is a by-product of this process.

  6. Device and method for measuring multi-phase fluid flow and density of fluid in a conduit having a gradual bend

    DOE Patents [OSTI]

    Ortiz, M.G.; Boucher, T.J.

    1998-10-27

    A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.

  7. A Sub-grid Model for an Array of Immersed Cylinders in Coarse-grid Multiphase Flow Simulations of a Carbon Capture Device

    SciTech Connect (OSTI)

    Sarkar, Avik; Sun, Xin; Sundaresan, Sankaran

    2012-12-01

    A post-combustion carbon-capture system utilizing a bubbling fluidized bed of sorbent particles is currently being developed as a part of the Carbon Capture and Simulation Initiative (CCSI) efforts. Adsorption of carbon dioxide (CO2) by these amine based sorbent particles is exothermic and arrays of immersed cylindrical heat transfer tubes are often utilized to maintain the lower temperatures favorable for CO2 capture. In multiphase computational fluid dynamics (CFD) simulations of the full-scale devices, which can be up to 10 m in size, approximately 103 cells are required in each dimension to accurately resolve the cylindrical tubes, which are only a few centimeters in diameter. Since the tubes cannot be resolved explicitly in CFD simulations, alternate methods to account for the influence of these immersed objects need to be developed.

  8. Device and method for measuring multi-phase fluid flow and density of fluid in a conduit having a gradual bend

    DOE Patents [OSTI]

    Ortiz, Marcos German (Idaho Falls, ID); Boucher, Timothy J. (Helena, MT)

    1998-01-01

    A system for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow.

  9. High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion

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

    | Department of Energy Fuel Reactivity Controlled Compression Ignition Combustion High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion An optimized dual-fuel PCCI concept, RCCI, is proposed. PDF icon deer10_reitz.pdf More Documents & Publications Effect of Compression Ratio and Piston Geometry on RCCI load limit Optimization of Advanced Diesel Engine Combustion Strategies Comparison of Conventional Diesel and Reactivity Controlled Compression Ignition (RCCI)

  10. Fuel Impacts on Soot Nanostructure and Reactivity | Department of Energy

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

    Impacts on Soot Nanostructure and Reactivity Fuel Impacts on Soot Nanostructure and Reactivity 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: The Pennsylvania State University PDF icon 2004_deer_song.pdf More Documents & Publications Fuel Formulation Effects on Diesel Fuel Injection, Combustion, Emissions and Emission Control Effect of Alternative Fuels on Soot Properties and Regeneration of Diesel Particulate Filters Impact of EGR on Soot Nanostructure and Reactivity

  11. Comparison of Conventional Diesel and Reactivity Controlled Compression

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

    Ignition (RCCI) Combustion in a Light-Duty Engine | Department of Energy Conventional Diesel and Reactivity Controlled Compression Ignition (RCCI) Combustion in a Light-Duty Engine Comparison of Conventional Diesel and Reactivity Controlled Compression Ignition (RCCI) Combustion in a Light-Duty Engine CFD modeling was used to compare conventional diesel and dual-fuel Reactivity Controlled Compression Ignition combustion at US Tier 2 Bin 5 NOx levels, while accounting for Diesel Exhaust Fluid

  12. Final Report Phase II: Performance Evaluation of Permeable Reactive

    Office of Environmental Management (EM)

    Barriers and Potential for Rejuvenation by Chemical Flushing | Department of Energy Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing Final Report Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing PDF icon Final Report Phase II:

  13. Monitoring CO 2 sequestration into deep saline aquifer and associated salt intrusion using coupled multiphase flow modeling and time lapse electrical resistivity tomography

    SciTech Connect (OSTI)

    Chuan Lu; CHI Zhang; Hai Hanag; Timothy C. Johnson

    2014-04-01

    Successful geological storage and sequestration of carbon dioxide (CO2) require efficient monitoring of the migration of CO2 plume during and after large-scale injection in order to verify the containment of the injected CO2 within the target formation and to evaluate potential leakage risk. Field studies have shown that surface and cross-borehole electrical resistivity tomography (ERT) can be a useful tool in imaging and characterizing solute transport in heterogeneous subsurface. In this synthetic study, we have coupled a 3-D multiphase flow model with a parallel 3-D time-lapse ERT inversion code to explore the feasibility of using time-lapse ERT for simultaneously monitoring the migration of CO2 plume in deep saline formation and potential brine intrusion into shallow fresh water aquifer. Direct comparisons of the inverted CO2 plumes resulting from ERT with multiphase flow simulation results indicate the ERT could be used to delineate the migration of CO2 plume. Detailed comparisons on the locations, sizes and shapes of CO2 plume and intruded brine plumes suggest that ERT inversion tends to underestimate the area review of the CO2 plume, but overestimate the thickness and total volume of the CO2 plume. The total volume of intruded brine plumes is overestimated as well. However, all discrepancies remain within reasonable ranges. Our study suggests that time-lapse ERT is a useful monitoring tool in characterizing the movement of injected CO2 into deep saline aquifer and detecting potential brine intrusion under large-scale field injection conditions.

  14. Double Shock Experiments and Reactive Flow Modeling of High Pressure...

    Office of Scientific and Technical Information (OSTI)

    Double Shock Experiments and Reactive Flow Modeling of High Pressure LX-17 Detonation Reaction Product States Citation Details In-Document Search Title: Double Shock Experiments ...

  15. PFLOTRAN User Manual: A Massively Parallel Reactive Flow and...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: PFLOTRAN User Manual: A Massively Parallel Reactive Flow and Transport Model for Describing Surface and Subsurface Processes Citation Details In-Document Search...

  16. PFLOTRAN User Manual: A Massively Parallel Reactive Flow and...

    Office of Scientific and Technical Information (OSTI)

    PFLOTRAN User Manual: A Massively Parallel Reactive Flow and Transport Model for Describing Surface and Subsurface Processes Lichtner, Peter OFM Research; Karra, Satish Los...

  17. New NIR Calibration Models Speed Biomass Composition and Reactivity...

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

    these valuable characteristics by using multivariate statistics to correlate laboratory data on biomass composition and reactivity to NIR spectra of a population of mixed...

  18. The Reactivity of Energetic Materials Under High Pressure and...

    Office of Scientific and Technical Information (OSTI)

    Under High Pressure and Temperature Citation Details In-Document Search Title: The Reactivity of Energetic Materials Under High Pressure and Temperature Authors: Manaa, M R ; ...

  19. Advancing Reactive Tracer Methods for Measurement of Thermal...

    Office of Scientific and Technical Information (OSTI)

    Title: Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in ... result in the lowering of the temperature of the produced fluids (thermal breakthrough). ...

  20. Sample Memorandum to Reactivate a Directive Placed on Hold (NOTE...

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

    Sample Memorandum to Reactivate a Directive Placed on Hold (NOTE: Per Office of Executive Secretariat procedures, please use Calibri, 12 point font for this memorandum.) (Effective...

  1. WP-07 Reactive Power Supplemental Proposal (wp07/initial)

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

    This modification is necessary in light of recent FERC cases regarding generation input cost for generation supplied reactive power and voltage control. On February 13, BPA...

  2. Advancing Reactive Tracer Methods for Measuring Thermal Evolution...

    Open Energy Info (EERE)

    and interpret reactive tracer tests - Development of suitable tracers to cover a range of reservoir temperature and residence time conditions - Testing the tools and tracers in a...

  3. Comparison of Conventional Diesel and Reactivity Controlled Compressio...

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

    Optimization of Advanced Diesel Engine Combustion Strategies High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion Effect of Compression Ratio and Piston ...

  4. Reactive Molecular Simulations of Protonation of Water Clusters...

    Office of Scientific and Technical Information (OSTI)

    of Water Clusters and Depletion of Acidity in H-ZSM-5 Zeolite Citation Details In-Document Search Title: Reactive Molecular Simulations of Protonation of Water Clusters ...

  5. Experimental Evidence for Self-Limiting Reactive Flow through...

    Office of Scientific and Technical Information (OSTI)

    Experimental Evidence for Self-Limiting Reactive Flow through a Fractured Cement Core: Implications for Time-Dependent Wellbore Leakage Citation Details In-Document Search Title: ...

  6. Long-Term Stewardship of Mixed Wastes: Passive Reactive Barriers...

    Office of Scientific and Technical Information (OSTI)

    Long-Term Stewardship of Mixed Wastes: Passive Reactive Barriers for Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal, and Radionuclide Contaminants Citation...

  7. A Uranium Bioremediation Reactive Transport Benchmark

    SciTech Connect (OSTI)

    Yabusaki, Steven B.; Sengor, Sevinc; Fang, Yilin

    2015-06-01

    A reactive transport benchmark problem set has been developed based on in situ uranium bio-immobilization experiments that have been performed at a former uranium mill tailings site in Rifle, Colorado, USA. Acetate-amended groundwater stimulates indigenous microorganisms to catalyze the reduction of U(VI) to a sparingly soluble U(IV) mineral. The interplay between the flow, acetate loading periods and rates, microbially-mediated and geochemical reactions leads to dynamic behavior in metal- and sulfate-reducing bacteria, pH, alkalinity, and reactive mineral surfaces. The benchmark is based on an 8.5 m long one-dimensional model domain with constant saturated flow and uniform porosity. The 159-day simulation introduces acetate and bromide through the upgradient boundary in 14-day and 85-day pulses separated by a 10 day interruption. Acetate loading is tripled during the second pulse, which is followed by a 50 day recovery period. Terminal electron accepting processes for goethite, phyllosilicate Fe(III), U(VI), and sulfate are modeled using Monod-type rate laws. Major ion geochemistry modeled includes mineral reactions, as well as aqueous and surface complexation reactions for UO2++, Fe++, and H+. In addition to the dynamics imparted by the transport of the acetate pulses, U(VI) behavior involves the interplay between bioreduction, which is dependent on acetate availability, and speciation-controlled surface complexation, which is dependent on pH, alkalinity and available surface complexation sites. The general difficulty of this benchmark is the large number of reactions (74), multiple rate law formulations, a multisite uranium surface complexation model, and the strong interdependency and sensitivity of the reaction processes. Results are presented for three simulators: HYDROGEOCHEM, PHT3D, and PHREEQC.

  8. Reactive ion etched substrates and methods of making and using

    DOE Patents [OSTI]

    Rucker, Victor C. (San Francisco, CA); Shediac, Rene (Oakland, CA); Simmons, Blake A. (San Francisco, CA); Havenstrite, Karen L. (New York, NY)

    2007-08-07

    Disclosed herein are substrates comprising reactive ion etched surfaces and specific binding agents immobilized thereon. The substrates may be used in methods and devices for assaying or isolating analytes in a sample. Also disclosed are methods of making the reactive ion etched surfaces.

  9. Biodiesel Fuel Property Effects on Particulate Matter Reactivity

    SciTech Connect (OSTI)

    Williams, A.; Black, S.; McCormick, R. L.

    2010-06-01

    Controlling diesel particulate emissions to meet the 2007 U.S. standard requires the use of a diesel particulate filter (DPF). The reactivity of soot, or the carbon fraction of particulate matter, in the DPF and the kinetics of soot oxidation are important in achieving better control of aftertreatment devices. Studies showed that biodiesel in the fuel can increase soot reactivity. This study therefore investigated which biodiesel fuel properties impact reactivity. Three fuel properties of interest included fuel oxygen content and functionality, fuel aromatic content, and the presence of alkali metals. To determine fuel effects on soot reactivity, the performance of a catalyzed DPF was measured with different test fuels through engine testing and thermo-gravimetric analysis. Results showed no dependence on the aromatic content or the presence of alkali metals in the fuel. The presence and form of fuel oxygen was the dominant contributor to faster DPF regeneration times and soot reactivity.

  10. CO2 leakage impacts on shallow groundwater. Field-scale reactive-transport simulations informed by observations at a natural analog site

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

    Keating, Elizabeth H.; Hakala, J. Alexandra; Viswanathan, Hari; Carey, J. William; Pawar, Rajesh; Guthrie, George D.; Fessenden-Rahn, Julianna

    2013-03-01

    It is challenging to predict the degree to which shallow groundwater might be affected by leaks from a CO2 sequestration reservoir, particularly over long time scales and large spatial scales. In this study observations at a CO2 enriched shallow aquifer natural analog were used to develop a predictive model which is then used to simulate leakage scenarios. This natural analog provides the opportunity to make direct field observations of groundwater chemistry in the presence of elevated CO2, to collect aquifer samples and expose them to CO2 under controlled conditions in the laboratory, and to test the ability of multiphase reactivemore » transport models to reproduce measured geochemical trends at the field-scale. The field observations suggest that brackish water entrained with the upwelling CO2 are a more significant source of trace metals than in situ mobilization of metals due to exposure to CO2. The study focuses on a single trace metal of concern at this site: U. Experimental results indicate that cation exchange/adsorption and dissolution/precipitation of calcite containing trace amounts of U are important reactions controlling U in groundwater at this site, and that the amount of U associated with calcite is fairly well constrained. Simulations incorporating these results into a 3-D multi-phase reactive transport model are able to reproduce the measured ranges and trends between pH, pCO2, Ca, total C, U and Cl-at the field site. Although the true fluxes at the natural analog site are unknown, the cumulative CO2 flux inferred from these simulations are approximately equivalent to 37.8E-3 MT, approximately corresponding to a .001% leak rate for injection at a large (750 MW) power plant. The leakage scenario simulations suggest that if the leak only persists for a short time the volume of aquifer contaminated by CO2-induced mobilization of U will be relatively small, yet persistent over 100 a.« less

  11. Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity

    DOE Patents [OSTI]

    Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

    2002-01-01

    A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

  12. Regional respiratory tract absorption of inhaled reactive gases

    SciTech Connect (OSTI)

    Miller, F.J.; Overton, J.H.; Kimbell, J.S.; Russell, M.L.

    1992-06-29

    Highly reactive gases present unique problems due to the number of factors which must be taken into account to determine regional respiratory tract uptake. The authors reviewed some of the physical, chemical, and biological factors that affect dose and that must be understood to interpret toxicological data, to evaluate experimental dosimetry studies, and to develop dosimetry models. Selected dosimetry experiments involving laboratory animals and humans were discussed, showing the variability and uptake according to animal species and respiratory tract region for various reactive gases. New experimental dosimetry approaches, such as those involving isotope ratio mass spectroscopy and cyclotron generation reactive gases, were discussed that offer great promise for improving the ability to study regional respiratory tract absorption of reactive gases. Various dosimetry modeling applications were discussed which demonstrate: the importance of airflow patterns for site-specific dosimetry in the upper respiratory tract, the influence of the anatomical model used to make inter- and intraspecies dosimetric comparisons, the influence of tracheobronchial path length on predicted dose curves, and the implications of ventilatory unit structure and volume on dosimetry and response. Collectively, these examples illustrate important aspects of regional respiratory tract absorption of inhaled reactive gases. Given the complex nature of extent and pattern of injury in the respiratory tract from exposure to reactive gases, understanding interspecies differences in the absorption of reactive gases will continue to be an important area for study.

  13. Experimental Observation of Quantum Oscillation of Surface Chemical Reactivities

    SciTech Connect (OSTI)

    Ma, X.; Jiang, P.; Qi, Y.; Jia, J.; Yang, Y.; Duan, W.; Li, W. X.; Bao, X.; Zhang, S. B.

    2007-05-29

    Here we present direct observation of a quantum reactivity with respect to the amounts of O2 adsorbed and the rates of surface oxidation as a function of film thickness on ultrathin (2-6 nm) Pb mesas by scanning tunneling microscopy. Simultaneous spectroscopic measurements on the electronic structures reveal a quantum oscillation that originates from quantum well states of the mesas, as a generalization of the Fabry-P{acute e}rot modes of confined electron waves. We expect the quantum reactivity to be a general phenomenon for most ultrathin metal films with broad implications, such as nanostructure tuning of surface reactivities and rational design of heterogeneous catalysts.

  14. Method for preparing hydride configurations and reactive metal surfaces

    DOE Patents [OSTI]

    Silver, G.L.

    1984-05-18

    A method for preparing reactive metal surfaces, particularly uranium surfaces is disclosed, whereby the metal is immediately reactive to hydrogen gas at room temperature and low pressure. The metal surfaces are first pretreated by exposure to an acid which forms an adherent hydride-bearing composition on the metal surface. Subsequent heating of the pretreated metal at a temperature sufficient to decompose the hydride coating in vacuum or inert gas renders the metal surface instantaneously reactive to hydrogen gas at room temperature and low pressure.

  15. Highly reactive light-dependent monoterpenes in the Amazon

    SciTech Connect (OSTI)

    Jardine, A. B.; Jardine, K. J.; Fuentes, J. D.; Martin, S. T.; Martins, G.; Durgante, F.; Carneiro, V.; Higuchi, N.; Manzi, A. O.; Chambers, J. Q.

    2015-03-06

    Despite orders of magnitude difference in atmospheric reactivity and great diversity in biological functioning, little is known about monoterpene speciation in tropical forests. Here we report vertically resolved ambient air mixing ratios for 12 monoterpenes in a central Amazon rainforest including observations of the highly reactive cis-β-ocimene (160 ppt), trans-β-ocimene (79 ppt), and terpinolene (32 ppt) which accounted for an estimated 21% of total monoterpene composition yet 55% of the upper canopy monoterpene ozonolysis rate. All 12 monoterpenes showed a mixing ratio peak in the upper canopy, with three demonstrating subcanopy peaks in 7 of 11 profiles. Leaf level emissions of highly reactive monoterpenes accounted for up to 1.9% of photosynthesis confirming light-dependent emissions across several Amazon tree genera. These results suggest that highly reactive monoterpenes play important antioxidant roles during photosynthesis in plants and serve as near-canopy sources of secondary organic aerosol precursors through atmospheric photooxidation via ozonolysis.

  16. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1987-10-27

    AMAX Research Development Center (AMAX R D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.

  17. Analytical methods for determining the reactivity of pyrochemical salts

    SciTech Connect (OSTI)

    Phillips, A.G.; Stakebake, J.L.

    1994-05-01

    Pyrochemical processes used for the purification of plutonium have generated quantities of residue that contain varying amounts of reactive metals such as potassium, sodium, calcium, and magnesium. These residues are currently considered hazardous and are being managed under RCRA because of the reactivity characteristic. This designation is based solely on process knowledge. Currently there is no approved procedure for determining the reactivity of a solid with water. A method is being developed to rapidly evaluate the reactivity of pyrochemical salts with water by measuring the rate of hydrogen generation. The method was initially tested with a magnesium containing pyrochemical salt. A detection limit of approximately 0.004 g of magnesium was established. A surrogate molten salt extraction residue was also tested. Extrapolation of test data resulted in a hydrogen generation rate of 4.4 mg/(g min).

  18. Pre-plated reactive diffusion-bonded battery electrode plaques

    DOE Patents [OSTI]

    Maskalick, Nicholas J. (Pittsburgh, PA)

    1984-01-01

    A high strength, metallic fiber battery plaque is made using reactive diffusion bonding techniques, where a substantial amount of the fibers are bonded together by an iron-nickel alloy.

  19. Reactive and Catalytic Air Purification Materials - Energy Innovation

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

    Portal Building Energy Efficiency Building Energy Efficiency Advanced Materials Advanced Materials Find More Like This Return to Search Reactive and Catalytic Air Purification Materials Naval Research Laboratory Contact NRL About This Technology Publications: PDF Document Publication AirPurification (546 KB) Technology Marketing SummarySorbents for the removal of toxic in-dustrial gases such as ammonia and phosgene. The materials offer reactive and/or catalytic sites within a high surface

  20. Reactive Molecular Simulations of Protonation of Water Clusters and

    Office of Scientific and Technical Information (OSTI)

    Depletion of Acidity in H-ZSM-5 Zeolite (Journal Article) | SciTech Connect Reactive Molecular Simulations of Protonation of Water Clusters and Depletion of Acidity in H-ZSM-5 Zeolite Citation Details In-Document Search Title: Reactive Molecular Simulations of Protonation of Water Clusters and Depletion of Acidity in H-ZSM-5 Zeolite Authors: Joshi, Kaushik L. [1] ; Psofogiannakis, George [1] ; Van Duin, Adri C. T. [2] ; Raman, Sumathy [3] + Show Author Affiliations Pennsylvania State

  1. Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer

    Office of Scientific and Technical Information (OSTI)

    Mechanochemistry (Journal Article) | SciTech Connect Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer Mechanochemistry Citation Details In-Document Search Title: Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer Mechanochemistry Authors: Wang, J ; Kouznetsova, T B ; Niu, Z ; Ong, M T ; Klukovich, H M ; Rheingold, A L ; Martinez, T J ; Craig, S L Publication Date: 2014-11-05 OSTI Identifier: 1184168 Report Number(s): LLNL-JRNL-663754 DOE

  2. Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer

    Office of Scientific and Technical Information (OSTI)

    Mechanochemistry (Journal Article) | SciTech Connect Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer Mechanochemistry Citation Details In-Document Search Title: Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer Mechanochemistry × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit

  3. Low Reactivity SI Engine Lubricant Program | Department of Energy

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

    Reactivity SI Engine Lubricant Program Low Reactivity SI Engine Lubricant Program Results showed that lubricant improvement allowed up to 4 degree improvement in spark advance at knock limited conditions resulting in potentially over 3 percent indicated efficiency improvement PDF icon deer11_alger.pdf More Documents & Publications Fuel & Lubricant Technologies Ionic Liquids as Novel Engine Lubricants or Lubricant Additives Fuel & Lubricant Technologies R&D

  4. Developing a robust geochemical and reactive transport model to evaluate

    Office of Scientific and Technical Information (OSTI)

    possible sources of arsenic at the CO[subscript 2] sequestration natural analog site in Chimayo, New Mexico (Journal Article) | SciTech Connect Journal Article: Developing a robust geochemical and reactive transport model to evaluate possible sources of arsenic at the CO[subscript 2] sequestration natural analog site in Chimayo, New Mexico Citation Details In-Document Search Title: Developing a robust geochemical and reactive transport model to evaluate possible sources of arsenic at the

  5. Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in

    Office of Scientific and Technical Information (OSTI)

    Geothermal Reservoirs: Final Report (Technical Report) | SciTech Connect Technical Report: Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report Citation Details In-Document Search Title: Advancing Reactive Tracer Methods for Measurement of Thermal Evolution in Geothermal Reservoirs: Final Report The injection of cold fluids into engineered geothermal system (EGS) and conventional geothermal reservoirs may be done to help extract heat

  6. Chemical Imaging and Dynamical Studies of Reactivity and Emergent Behavior

    Office of Scientific and Technical Information (OSTI)

    in Complex Interfacial Systems. Final Technical Report (Technical Report) | SciTech Connect Chemical Imaging and Dynamical Studies of Reactivity and Emergent Behavior in Complex Interfacial Systems. Final Technical Report Citation Details In-Document Search Title: Chemical Imaging and Dynamical Studies of Reactivity and Emergent Behavior in Complex Interfacial Systems. Final Technical Report This research program explored the efficacy of using molecular-level manipulation, imaging and

  7. Directional Reactive Power Ground Plane Transmission - Energy Innovation

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

    Portal Vehicles and Fuels Vehicles and Fuels Energy Storage Energy Storage Find More Like This Return to Search Directional Reactive Power Ground Plane Transmission Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryORNL researchers have developed a pioneering power alternative to batteries using directional reactive power. Batteries are currently the primary option for powering mobile electronic equipment; however, batteries are heavy and battery

  8. Chemically Reactive Working Fluids for the Capture and Transport of

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

    Concentrated Solar Thermal Energy for Power Generation | Department of Energy Chemically Reactive Working Fluids for the Capture and Transport of Concentrated Solar Thermal Energy for Power Generation Chemically Reactive Working Fluids for the Capture and Transport of Concentrated Solar Thermal Energy for Power Generation This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23-25, 2013 near Phoenix, Arizona. PDF icon

  9. Shock Desensitization Experiments and Reactive Flow Modeling on

    Office of Scientific and Technical Information (OSTI)

    Self-Sustaining LX-17 Detonation Waves (Conference) | SciTech Connect Shock Desensitization Experiments and Reactive Flow Modeling on Self-Sustaining LX-17 Detonation Waves Citation Details In-Document Search Title: Shock Desensitization Experiments and Reactive Flow Modeling on Self-Sustaining LX-17 Detonation Waves Authors: Vandersall, K S ; Garcia, F ; Tarver, C M ; Fried, L E Publication Date: 2014-06-24 OSTI Identifier: 1169869 Report Number(s): LLNL-CONF-656218

  10. Measuring and monitoring KIPT Neutron Source Facility Reactivity

    SciTech Connect (OSTI)

    Cao, Yan; Gohar, Yousry; Zhong, Zhaopeng

    2015-08-01

    Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on developing and constructing a neutron source facility at Kharkov, Ukraine. The facility consists of an accelerator-driven subcritical system. The accelerator has a 100 kW electron beam using 100 MeV electrons. The subcritical assembly has keff less than 0.98. To ensure the safe operation of this neutron source facility, the reactivity of the subcritical core has to be accurately determined and continuously monitored. A technique which combines the area-ratio method and the flux-to-current ratio method is purposed to determine the reactivity of the KIPT subcritical assembly at various conditions. In particular, the area-ratio method can determine the absolute reactivity of the subcritical assembly in units of dollars by performing pulsed-neutron experiments. It provides reference reactivities for the flux-to-current ratio method to track and monitor the reactivity deviations from the reference state while the facility is at other operation modes. Monte Carlo simulations are performed to simulate both methods using the numerical model of the KIPT subcritical assembly. It is found that the reactivities obtained from both the area-ratio method and the flux-to-current ratio method are spatially dependent on the neutron detector locations and types. Numerical simulations also suggest optimal neutron detector locations to minimize the spatial effects in the flux-to-current ratio method. The spatial correction factors are calculated using Monte Carlo methods for both measuring methods at the selected neutron detector locations. Monte Carlo simulations are also performed to verify the accuracy of the flux-to-current ratio method in monitoring the reactivity swing during a fuel burnup cycle.

  11. KINETIC MODELING OF A FISCHER-TROPSCH REACTION OVER A COBALT CATALYST IN A SLURRY BUBBLE COLUMN REACTOR FOR INCORPORATION INTO A COMPUTATIONAL MULTIPHASE FLUID DYNAMICS MODEL

    SciTech Connect (OSTI)

    Anastasia Gribik; Doona Guillen, PhD; Daniel Ginosar, PhD

    2008-09-01

    Currently multi-tubular fixed bed reactors, fluidized bed reactors, and slurry bubble column reactors (SBCRs) are used in commercial Fischer Tropsch (FT) synthesis. There are a number of advantages of the SBCR compared to fixed and fluidized bed reactors. The main advantage of the SBCR is that temperature control and heat recovery are more easily achieved. The SBCR is a multiphase chemical reactor where a synthesis gas, comprised mainly of H2 and CO, is bubbled through a liquid hydrocarbon wax containing solid catalyst particles to produce specialty chemicals, lubricants, or fuels. The FT synthesis reaction is the polymerization of methylene groups [-(CH2)-] forming mainly linear alkanes and alkenes, ranging from methane to high molecular weight waxes. The Idaho National Laboratory is developing a computational multiphase fluid dynamics (CMFD) model of the FT process in a SBCR. This paper discusses the incorporation of absorption and reaction kinetics into the current hydrodynamic model. A phased approach for incorporation of the reaction kinetics into a CMFD model is presented here. Initially, a simple kinetic model is coupled to the hydrodynamic model, with increasing levels of complexity added in stages. The first phase of the model includes incorporation of the absorption of gas species from both large and small bubbles into the bulk liquid phase. The driving force for the gas across the gas liquid interface into the bulk liquid is dependent upon the interfacial gas concentration in both small and large bubbles. However, because it is difficult to measure the concentration at the gas-liquid interface, coefficients for convective mass transfer have been developed for the overall driving force between the bulk concentrations in the gas and liquid phases. It is assumed that there are no temperature effects from mass transfer of the gas phases to the bulk liquid phase, since there are only small amounts of dissolved gas in the liquid phase. The product from the incorporation of absorption is the steady state concentration profile of the absorbed gas species in the bulk liquid phase. The second phase of the model incorporates a simplified macrokinetic model to the mass balance equation in the CMFD code. Initially, the model assumes that the catalyst particles are sufficiently small such that external and internal mass and heat transfer are not rate limiting. The model is developed utilizing the macrokinetic rate expression developed by Yates and Satterfield (1991). Initially, the model assumes that the only species formed other than water in the FT reaction is C27H56. Change in moles of the reacting species and the resulting temperature of the catalyst and fluid phases is solved simultaneously. The macrokinetic model is solved in conjunction with the species transport equations in a separate module which is incorporated into the CMFD code.

  12. Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

    SciTech Connect (OSTI)

    Splitter, Derek A; Reitz, Rolf

    2014-01-01

    Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

  13. Initiating the Validation of CCIM Processability for Multi-phase all Ceramic (SYNROC) HLW Form: Plan for Test BFY14CCIM-C

    SciTech Connect (OSTI)

    Vince Maio

    2014-08-01

    This plan covers test BFY14CCIM-C which will be a first–of–its-kind demonstration for the complete non-radioactive surrogate production of multi-phase ceramic (SYNROC) High Level Waste Forms (HLW) using Cold Crucible Induction Melting (CCIM) Technology. The test will occur in the Idaho National Laboratory’s (INL) CCIM Pilot Plant and is tentatively scheduled for the week of September 15, 2014. The purpose of the test is to begin collecting qualitative data for validating the ceramic HLW form processability advantages using CCIM technology- as opposed to existing ceramic–lined Joule Heated Melters (JHM) currently producing BSG HLW forms. The major objectives of BFY14CCIM-C are to complete crystalline melt initiation with a new joule-heated resistive starter ring, sustain inductive melting at temperatures between 1600 to 1700°C for two different relatively high conductive materials representative of the SYNROC ceramic formation inclusive of a HLW surrogate, complete melter tapping and pouring of molten ceramic material in to a preheated 4 inch graphite canister and a similar canister at room temperature. Other goals include assessing the performance of a new crucible specially designed to accommodate the tapping and pouring of pure crystalline forms in contrast to less recalcitrant amorphous glass, assessing the overall operational effectiveness of melt initiation using a resistive starter ring with a dedicated power source, and observing the tapped molten flow and subsequent relatively quick crystallization behavior in pans with areas identical to standard HLW disposal canisters. Surrogate waste compositions with ceramic SYNROC forming additives and their measured properties for inductive melting, testing parameters, pre-test conditions and modifications, data collection requirements, and sampling/post-demonstration analysis requirements for the produced forms are provided and defined.

  14. Environmentally stable reactive alloy powders and method of making same

    DOE Patents [OSTI]

    Anderson, I.E.; Lograsso, B.K.; Terpstra, R.L.

    1998-09-22

    Apparatus and method are disclosed for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloys needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment. 7 figs.

  15. Apparatus for making environmentally stable reactive alloy powders

    DOE Patents [OSTI]

    Anderson, I.E.; Lograsso, B.K.; Terpstra, R.L.

    1996-12-31

    Apparatus and method are disclosed for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloyants needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment. 7 figs.

  16. Method and apparatus for measuring reactivity of fissile material

    DOE Patents [OSTI]

    Lee, D.M.; Lindquist, L.O.

    1982-09-07

    Given are a method and apparatus for measuring nondestructively and noninvasively (i.e., using no internal probing) the burnup, reactivity, or fissile content of any material which emits neutrons and which has fissionable components. The assay is accomplished by altering the return flux of neutrons into the fuel assembly by means of changing the reflecting material. The existing passive neutron emissions in the material being assayed are used as the source of interrogating neutrons. Two measurements of either emitted neutron or emitted gamma-ray count rates are made and are then correlated to either reactivity, burnup, or fissionable content of the material being assayed, thus providing a measurement of either reactivity, burnup, or fissionable content of the material being assayed. Spent fuel which has been freshly discharged from a reactor can be assayed using this method and apparatus. Precisions of 1000 MWd/tU appear to be feasible.

  17. Apparatus for making environmentally stable reactive alloy powders

    DOE Patents [OSTI]

    Anderson, Iver E. (Ames, IA); Lograsso, Barbara K. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    1996-12-31

    Apparatus and method for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloyants needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment.

  18. Environmentally stable reactive alloy powders and method of making same

    DOE Patents [OSTI]

    Anderson, Iver E. (Ames, IA); Lograsso, Barbara K. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    1998-09-22

    Apparatus and method for making powder from a metallic melt by atomizing the melt to form droplets and reacting the droplets downstream of the atomizing location with a reactive gas. The droplets are reacted with the gas at a temperature where a solidified exterior surface is formed thereon and where a protective refractory barrier layer (reaction layer) is formed whose penetration into the droplets is limited by the presence of the solidified surface so as to avoid selective reduction of key reactive alloyants needed to achieve desired powder end use properties. The barrier layer protects the reactive powder particles from environmental constituents such as air and water in the liquid or vapor form during subsequent fabrication of the powder to end-use shapes and during use in the intended service environment.

  19. Picture of the Week: Making the (reactive) case for explosives science

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

    28 Making the (reactive) case for explosives science A "reactive case" is a new concept in explosives science currently being tested at Los Alamos National Laboratory. A reactive case would do more than just contain an explosive, but rather become part of the explosive event itself, actually enhancing or boosting the explosion while decreasing far-field fragmentation damage. October 16, 2015 explosion Making the (reactive) case for explosives science Making the (reactive) case for

  20. Plasma & reactive ion etching to prepare ohmic contacts

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    2002-01-01

    A method of making a low-resistance electrical contact between a metal and a layer of p-type CdTe surface by plasma etching and reactive ion etching comprising: a) placing a CdS/CdTe layer into a chamber and evacuating said chamber; b) backfilling the chamber with Argon or a reactive gas to a pressure sufficient for plasma ignition; and c) generating plasma ignition by energizing a cathode which is connected to a power supply to enable the plasma to interact argon ions alone or in the presence of a radio-frequency DC self-bias voltage with the p-CdTe surface.

  1. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  3. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-03-06

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  4. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  5. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  6. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  7. Increasing Class C fly ash reduces alkali silica reactivity

    SciTech Connect (OSTI)

    Hicks, J.K.

    2007-07-01

    Contrary to earlier studies, it has been found that incremental additions of Class C fly ash do reduce alkali silica reactivity (ASR), in highly reactive, high alkali concrete mixes. AST can be further reduced by substituting 5% metakaolin or silica fume for the aggregate in concrete mixes with high (more than 30%) Class C fly ash substitution. The paper reports results of studies using Class C fly ash from the Labadie Station plant in Missouri which typically has between 1.3 and 1.45% available alkalis by ASTM C311. 7 figs.

  8. The Reactivity of Energetic Materials Under High Pressure and Temperature

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect The Reactivity of Energetic Materials Under High Pressure and Temperature Citation Details In-Document Search Title: The Reactivity of Energetic Materials Under High Pressure and Temperature Authors: Manaa, M R ; Fried, L E Publication Date: 2013-09-17 OSTI Identifier: 1209648 Report Number(s): LLNL-JRNL-643808 DOE Contract Number: DE-AC52-07NA27344 Resource Type: Journal Article Resource Relation: Journal Name: Advances in Quantum Chemistry, vol. 69, no.

  9. Approximate photochemical dynamics of azobenzene with reactive force fields

    SciTech Connect (OSTI)

    Li, Yan; Hartke, Bernd

    2013-12-14

    We have fitted reactive force fields of the ReaxFF type to the ground and first excited electronic states of azobenzene, using global parameter optimization by genetic algorithms. Upon coupling with a simple energy-gap transition probability model, this setup allows for completely force-field-based simulations of photochemical cis?trans- and trans?cis-isomerizations of azobenzene, with qualitatively acceptable quantum yields. This paves the way towards large-scale dynamics simulations of molecular machines, including bond breaking and formation (via the reactive force field) as well as photochemical engines (presented in this work)

  10. Neutron economic reactivity control system for light water reactors

    DOE Patents [OSTI]

    Luce, Robert G.; McCoy, Daniel F.; Merriman, Floyd C.; Gregurech, Steve

    1989-01-01

    A neutron reactivity control system for a LWBR incorporating a stationary seed-blanket core arrangement. The core arrangement includes a plurality of contiguous hexagonal shaped regions. Each region has a central and a peripheral blanket area juxapositioned an annular seed area. The blanket areas contain thoria fuel rods while the annular seed area includes seed fuel rods and movable thoria shim control rods.

  11. Method and apparatus for measuring reactivity of fissile material

    DOE Patents [OSTI]

    Lee, David M. (Los Alamos, NM); Lindquist, Lloyd O. (Santa Fe, NM)

    1985-01-01

    Given are a method and apparatus for measuring nondestructively and non-invasively (i.e., using no internal probing) the burnup, reactivity, or fissile content of any material which emits neutrons and which has fissionable components. No external neutron-emitting interrogation source or fissile material is used and no scanning is required, although if a profile is desired scanning can be used. As in active assays, here both reactivity and content of fissionable material can be measured. The assay is accomplished by altering the return flux of neutrons into the fuel assembly. The return flux is altered by changing the reflecting material. The existing passive neutron emissions in the material being assayed are used as the source of interrogating neutrons. Two measurements of either emitted neutron or emitted gamma-ray count rates are made and are then correlated to either reactivity, burnup, or fissionable content of the material being assayed, thus providing a measurement of either reactivity, burnup, or fissionable content of the material being assayed. Spent fuel which has been freshly discharged from a reactor can be assayed using this method and apparatus. Precisions of 1000 MWd/tU appear to be feasible.

  12. Highly reactive light-dependent monoterpenes in the Amazon

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

    Jardine, A. B.; Jardine, K. J.; Fuentes, J. D.; Martin, S. T.; Martins, G.; Durgante, F.; Carneiro, V.; Higuchi, N.; Manzi, A. O.; Chambers, J. Q.

    2015-03-06

    Despite orders of magnitude difference in atmospheric reactivity and great diversity in biological functioning, little is known about monoterpene speciation in tropical forests. Here we report vertically resolved ambient air mixing ratios for 12 monoterpenes in a central Amazon rainforest including observations of the highly reactive cis-β-ocimene (160 ppt), trans-β-ocimene (79 ppt), and terpinolene (32 ppt) which accounted for an estimated 21% of total monoterpene composition yet 55% of the upper canopy monoterpene ozonolysis rate. All 12 monoterpenes showed a mixing ratio peak in the upper canopy, with three demonstrating subcanopy peaks in 7 of 11 profiles. Leaf level emissionsmore » of highly reactive monoterpenes accounted for up to 1.9% of photosynthesis confirming light-dependent emissions across several Amazon tree genera. These results suggest that highly reactive monoterpenes play important antioxidant roles during photosynthesis in plants and serve as near-canopy sources of secondary organic aerosol precursors through atmospheric photooxidation via ozonolysis.« less

  13. Local control of reactive power by distributed photovoltaic generators

    SciTech Connect (OSTI)

    Chertkov, Michael; Turitsyn, Konstantin; Sulc, Petr; Backhaus, Scott

    2010-01-01

    High penetration levels of distributed photovoltaic (PV) generation on an electrical distribution circuit may severely degrade power quality due to voltage sags and swells caused by rapidly varying PV generation during cloud transients coupled with the slow response of existing utility compensation and regulation equipment. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We suggest a local control scheme that dispatches reactive power from each PV inverter based on local instantaneous measurements of the real and reactive components of the consumed power and the real power generated by the PVs. Using one adjustable parameter per circuit, we balance the requirements on power quality and desire to minimize thermal losses. Numerical analysis of two exemplary systems, with comparable total PV generation albeit a different spatial distribution, show how to adjust the optimization parameter depending on the goal. Overall, this local scheme shows excellent performance; it's capable of guaranteeing acceptable power quality and achieving significant saving in thermal losses in various situations even when the renewable generation in excess of the circuit own load, i.e. feeding power back to the higher-level system.

  14. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  15. Reactive multilayers fabricated by vapor deposition. A critical review

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

    Adams, D. P.

    2014-10-02

    The reactive multilayer thin films are a class of energetic materials that continue to attract attention for use in joining applications and as igniters. Generally composed of two reactants, these heterogeneous solids can be stimulated by an external source to promptly release stored chemical energy in a sudden emission of light and heat. In our critical review article, results from recent investigations of these materials are discussed. Discussion begins with a brief description of the vapor deposition techniques that provide accurate control of layer thickness and film composition. More than 50 reactive film compositions have been reported to date, withmore » most multilayers fabricated by magnetron sputter deposition or electron-beam evaporation. In later sections, we review how multilayer ignition threshold, reaction rate, and total heat are tailored via thin film design. For example, planar multilayers with nanometer-scale periodicity exhibit rapid, self-sustained reactions with wavefront velocities up to 100 m/s. Numeric and analytical models have elucidated many of the fundamental processes that underlie propagating exothermic reactions while demonstrating how reaction rates vary with multilayer design. Recent, time-resolved diffraction and imaging studies have further revealed the phase transformations and the wavefront dynamics associated with propagating chemical reactions. Many reactive multilayers (e.g., Co/Al) form product phases that are consistent with published equilibrium phase diagrams, yet a few systems, such as Pt/Al, develop metastable products. The final section highlights current and emerging applications of reactive multilayers. Examples include reactive Ni(V)/Al and Pd/Al multilayers which have been developed for localized soldering of heat-sensitive components.« less

  16. Reactive multilayers fabricated by vapor deposition. A critical review

    SciTech Connect (OSTI)

    Adams, D. P.

    2014-10-02

    The reactive multilayer thin films are a class of energetic materials that continue to attract attention for use in joining applications and as igniters. Generally composed of two reactants, these heterogeneous solids can be stimulated by an external source to promptly release stored chemical energy in a sudden emission of light and heat. In our critical review article, results from recent investigations of these materials are discussed. Discussion begins with a brief description of the vapor deposition techniques that provide accurate control of layer thickness and film composition. More than 50 reactive film compositions have been reported to date, with most multilayers fabricated by magnetron sputter deposition or electron-beam evaporation. In later sections, we review how multilayer ignition threshold, reaction rate, and total heat are tailored via thin film design. For example, planar multilayers with nanometer-scale periodicity exhibit rapid, self-sustained reactions with wavefront velocities up to 100 m/s. Numeric and analytical models have elucidated many of the fundamental processes that underlie propagating exothermic reactions while demonstrating how reaction rates vary with multilayer design. Recent, time-resolved diffraction and imaging studies have further revealed the phase transformations and the wavefront dynamics associated with propagating chemical reactions. Many reactive multilayers (e.g., Co/Al) form product phases that are consistent with published equilibrium phase diagrams, yet a few systems, such as Pt/Al, develop metastable products. The final section highlights current and emerging applications of reactive multilayers. Examples include reactive Ni(V)/Al and Pd/Al multilayers which have been developed for localized soldering of heat-sensitive components.

  17. The correlation between reactivity and ash mineralogy of coke

    SciTech Connect (OSTI)

    Kerkkonen, O.; Mattila, E.; Heiniemi, R.

    1996-12-31

    Rautaruukki is a modern integrated Finnish steel works having a production of 2.4 mil. t/year of flat products. The total fuel consumption of the two blast furnaces in 1994 was 435 kg/t HM. Coke used was 345 kg/t HM and oil injection was 90 kg/t HM. The coking plant was taken in to operation in 1987 and is the only one in Finland, which means that the coking tradition is very short. Coke production is 0.9 mil. t/year. The coking blends include 70--80% medium volatile coals having a wide range of total dilatation. From time to time disturbances in the operation of the blast furnaces have occurred in spite of the fact that the reactivity of the coke used has remained constant or even decreased. It was thought necessary to investigate the factors affecting coke reactivity, in order to better understand the results of the reactivity test. This paper deals with carbonization tests done in a 7 kg test oven using nine individual coals having volatile-matter contents of 17--36% (dry) and seven blends made from these coals. Coke reactivity with CO{sub 2} at 1100 C (CRI) and coke strength after reaction (CSR) were determined using the test developed by the Nippon Steel Corporation. The influence of coke carbon form, porosity and especially ash mineralogy on the coke reactivity were examined. The effects of some additives; petroleum coke (pet coke), the spillage material from the coke ovens and oxidized coal, on coke quality were also studied. Typical inorganic minerals found in coals were added to one of the high volatile coals, which was then coked to determine the affect of the minerals on the properties of the coke produced.

  18. A Reactive Force Field study of Li/C Systems for Electrical Energy...

    Office of Scientific and Technical Information (OSTI)

    Reactive Force Field study of LiC Systems for Electrical Energy Storage Citation Details In-Document Search Title: A Reactive Force Field study of LiC Systems for Electrical...

  19. Catalytic and reactive polypeptides and methods for their preparation and use

    DOE Patents [OSTI]

    Schultz, Peter (Oakland, CA)

    1993-01-01

    Catalytic and reactive polypeptides include a binding site specific for a reactant or reactive intermediate involved in a chemical reaction of interest. The polypeptides further include at least one active functionality proximate the bi.

  20. Reactivity control mechanisms for a HPLWR fuel assembly

    SciTech Connect (OSTI)

    Schlagenhaufer, Marc; Schulenberg, Thomas; Vogt, Bastian

    2007-07-01

    A parametric study of different reactivity control mechanisms has been performed for the cross section of a single fuel assembly of a High Performance Light Water Reactor using the Monte Carlo code MCNP5. The fuel temperature feedback, known as the Doppler Effect, and the coolant density feedback have been determined for fresh UO{sub 2} fuel in a large range of fuel and coolant temperatures. The local shutdown reactivity of different control rods with different absorber materials has been predicted. The neutron flux inside the control rods, the power profile in the fuel pins with and without control rods and the coolant density coefficient have been evaluated for future core optimization. Methods to improve the power profile with additional absorbers mounted outside the fuel cluster have been studied exemplarily. (authors)

  1. Physical Characterization and Steam Chemical Reactivity of Carbon Fiber Composites

    SciTech Connect (OSTI)

    Anderl, Robert Andrew; Pawelko, Robert James; Smolik, Galen Richard

    2001-05-01

    This report documents experiments and analyses that have been done at the Idaho National Engineering and Environmental Laboratory (INEEL) to measure the steam chemical reactivity of two types of carbon fiber composites, NS31 and NB31, proposed for use at the divertor strike points in an ITER-like tokamak. These materials are 3D CFCs constituted by a NOVOLTEX preform and densified by pyrocarbon infiltration and heat treatment. NS31 differs from NB31 in that the final infiltration was done with liquid silicon to reduce the porosity and enhance the thermal conductivity of the CFC. Our approach in this work was twofold: (1) physical characterization measurements of the specimens and (2) measurements of the chemical reactivity of specimens exposed to steam.

  2. Engine combustion control at low loads via fuel reactivity stratification

    DOE Patents [OSTI]

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2014-10-07

    A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.

  3. Catalytic destruction of groundwater contaminants in reactive extraction wells

    DOE Patents [OSTI]

    McNab, Jr., Walt W.; Reinhard, Martin

    2002-01-01

    A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

  4. Solid polymer battery electrolyte and reactive metal-water battery

    DOE Patents [OSTI]

    Harrup, Mason K.; Peterson, Eric S.; Stewart, Frederick F.

    2000-01-01

    In one implementation, a reactive metal-water battery includes an anode comprising a metal in atomic or alloy form selected from the group consisting of periodic table Group 1A metals, periodic table Group 2A metals and mixtures thereof. The battery includes a cathode comprising water. Such also includes a solid polymer electrolyte comprising a polyphosphazene comprising ligands bonded with a phosphazene polymer backbone. The ligands comprise an aromatic ring containing hydrophobic portion and a metal ion carrier portion. The metal ion carrier portion is bonded at one location with the polymer backbone and at another location with the aromatic ring containing hydrophobic portion. The invention also contemplates such solid polymer electrolytes use in reactive metal/water batteries, and in any other battery.

  5. Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium

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

    Milling Site: Monticello, Utah | Department of Energy Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah PDF icon Alternatives for Mending a Permeable Reactive Barrier at a Former Uranium Milling Site: Monticello, Utah More

  6. Reactive Distillation for Esterification of Bio-based Organic Acids

    SciTech Connect (OSTI)

    Fields, Nathan; Miller, Dennis J.; Asthana, Navinchandra S.; Kolah, Aspi K.; Vu, Dung; Lira, Carl T.

    2008-09-23

    The following is the final report of the three year research program to convert organic acids to their ethyl esters using reactive distillation. This report details the complete technical activities of research completed at Michigan State University for the period of October 1, 2003 to September 30, 2006, covering both reactive distillation research and development and the underlying thermodynamic and kinetic data required for successful and rigorous design of reactive distillation esterification processes. Specifically, this project has led to the development of economical, technically viable processes for ethyl lactate, triethyl citrate and diethyl succinate production, and on a larger scale has added to the overall body of knowledge on applying fermentation based organic acids as platform chemicals in the emerging biorefinery. Organic acid esters constitute an attractive class of biorenewable chemicals that are made from corn or other renewable biomass carbohydrate feedstocks and replace analogous petroleum-based compounds, thus lessening U.S. dependence on foreign petroleum and enhancing overall biorefinery viability through production of value-added chemicals in parallel with biofuels production. Further, many of these ester products are candidates for fuel (particularly biodiesel) components, and thus will serve dual roles as both industrial chemicals and fuel enhancers in the emerging bioeconomy. The technical report from MSU is organized around the ethyl esters of four important biorenewables-based acids: lactic acid, citric acid, succinic acid, and propionic acid. Literature background on esterification and reactive distillation has been provided in Section One. Work on lactic acid is covered in Sections Two through Five, citric acid esterification in Sections Six and Seven, succinic acid in Section Eight, and propionic acid in Section Nine. Section Ten covers modeling of ester and organic acid vapor pressure properties using the SPEAD (Step Potential Equilibrium and Dynamics) method.

  7. Point kinetics calculations with fully coupled thermal fluids reactivity feedback

    SciTech Connect (OSTI)

    Zhang, H.; Zou, L.; Andrs, D.; Zhao, H.; Martineau, R.

    2013-07-01

    The point kinetics model has been widely used in the analysis of the transient behavior of a nuclear reactor. In the traditional nuclear reactor system safety analysis codes such as RELAP5, the reactivity feedback effects are calculated in a loosely coupled fashion through operator splitting approach. This paper discusses the point kinetics calculations with the fully coupled thermal fluids and fuel temperature feedback implemented into the RELAP-7 code currently being developed with the MOOSE framework. (authors)

  8. Reactivation of landslides by surface subsidence from longwall mining

    SciTech Connect (OSTI)

    Iannacchione, A.T.; Ackman, T.E.

    1984-12-01

    Subsidence research by the US Bureau of Mines has identified and documented the occurrence of landslides over a longwall mining area in the Dunkard basin. Mining by longwall methods has been observed or produce a gradual surface subsidence profile of up to 60% of the thickness of the mined coal bed. The gradual subsidence of panels averaging 600 x 5000 ft (180 x 1525 m) can cause reactivation of older landslide deposits by decreasing the support to the landslide toe area. Examination of surficial features over a longwall mining area comprised of nine panels has led to the identification of several reactivated landslides. The two largest landslides occurred above a thin sandstone member with several associated springs. The largest landslides ranged from 100 to 300 ft (30 to 90 m) in length and from 100 to 200 ft (30 to 60 m) in width. Maximum scarp-slope displacements were approximately 7 ft (2 m). Less significant mass wasting was also observed over the longwall panels. Identification of landslides was accomplished through examination of premining aerial photographs and geologic field investigation. Characterization of reactivated zones was achieved through evaluation of current aerial 2-ft (0.6-m) surface contour map and field surveys. Recognition of problem areas will make civic and mining personnel aware of the landslide potential so that damage in such areas can be minimized.

  9. Reactivity transients during a blowdown in a MSIV closure ATWS

    SciTech Connect (OSTI)

    Cheng, H.S.; Diamond, D.J. (Brookhaven National Lab., Upton, NY (USA))

    1988-01-01

    Anticipated transients without scram (ATWS) events have received considerable attention in the past and are still a subject of great interest in severe-accident analysis. Of special interest is the effect of the low-pressure emergency core cooling system (ECCS) on the plant response following a blowdown by the automatic depressurization system (ADS). There is a potential for positive reactivity insertion due to the cold water injection of the low-pressure coolant injection (LPCI) system and the low-pressure core spray system in a boiling water reactor (BWR)/4. The main concern is whether a power excursion and pressure oscillation can occur in such an event. Furthermore, since thermal-hydraulic feedback plays an important role in these accidents, the uncertainty of the reactivity feedback coefficients used can impact the outcome of the analysis for such a power excursion. The objectives of the work reported in this paper are to study the consequences of the reactivity transients during a blowdown in an ATWS event with closure of the main steam isolation valves (MSIVs) and to evaluate the effect of the LPCI system and the sensitivity of plant response to the feedback coefficients. This work was performed with the Brookhaven National Laboratory plant analyzer.

  10. Ionic Liquids: Radiation Chemistry, Solvation Dynamics and Reactivity Patterns

    SciTech Connect (OSTI)

    Wishart, J.F.

    2011-06-12

    Ionic liquids (ILs) are a rapidly expanding family of condensed-phase media with important applications in energy production, nuclear fuel and waste processing, improving the efficiency and safety of industrial chemical processes, and pollution prevention. ILs generally have low volatilities and are combustion-resistant, highly conductive, recyclable and capable of dissolving a wide variety of materials. They are finding new uses in chemical synthesis, catalysis, separations chemistry, electrochemistry and other areas. Ionic liquids have dramatically different properties compared to conventional molecular solvents, and they provide a new and unusual environment to test our theoretical understanding of primary radiation chemistry, charge transfer and other reactions. We are interested in how IL properties influence physical and dynamical processes that determine the stability and lifetimes of reactive intermediates and thereby affect the courses of reactions and product distributions. We study these issues by characterization of primary radiolysis products and measurements of their yields and reactivity, quantification of electron solvation dynamics and scavenging of electrons in different states of solvation. From this knowledge we wish to learn how to predict radiolytic mechanisms and control them or mitigate their effects on the properties of materials used in nuclear fuel processing, for example, and to apply IL radiation chemistry to answer questions about general chemical reactivity in ionic liquids that will aid in the development of applications listed above. Very early in our radiolysis studies it became evident that the slow solvation dynamics of the excess electron in ILs (which vary over a wide viscosity range) increase the importance of pre-solvated electron reactivity and consequently alter product distributions and subsequent chemistry. This difference from conventional solvents has profound effects on predicting and controlling radiolytic yields, which need to be quantified for the successful use under radiolytic conditions. Electron solvation dynamics in ILs are measured directly when possible and estimated using proxies (e.g. coumarin-153 dynamic emission Stokes shifts or benzophenone anion solvation) in other cases. Electron reactivity is measured using ultrafast kinetics techniques for comparison with the solvation process.

  11. PACKAGE (Plasma Analysis, Chemical Kinetics and Generator Efficiency): a computer program for the calculation of partial chemical equilibrium/partial chemical rate controlled composition of multiphased mixtures under one dimensional steady flow

    SciTech Connect (OSTI)

    Yousefian, V.; Weinberg, M.H.; Haimes, R.

    1980-02-01

    The NASA CEC Code was the starting point for PACKAGE, whose function is to evaluate the composition of a multiphase combustion product mixture under the following chemical conditions: (1) total equilibrium with pure condensed species; (2) total equilibrium with ideal liquid solution; (3) partial equilibrium/partial finite rate chemistry; and (4) fully finite rate chemistry. The last three conditions were developed to treat the evolution of complex mixtures such as coal combustion products. The thermodynamic variable pairs considered are either pressure (P) and enthalpy, P and entropy, at P and temperature. Minimization of Gibbs free energy is used. This report gives detailed discussions of formulation and input/output information used in the code. Sample problems are given. The code development, description, and current programming constraints are discussed. (DLC)

  12. Hydrogen Atom Reactivity toward Aqueous tert-Butyl Alcohol

    SciTech Connect (OSTI)

    Lymar S. V.; Schwarz, H.A.

    2012-02-09

    Through a combination of pulse radiolysis, purification, and analysis techniques, the rate constant for the H + (CH{sub 3}){sub 3}COH {yields} H{sub 2} + {sm_bullet}CH{sub 2}C(CH{sub 3}){sub 2}OH reaction in aqueous solution is definitively determined to be (1.0 {+-} 0.15) x 10{sup 5} M{sup -1} s{sup -1}, which is about half of the tabulated number and 10 times lower than the more recently suggested revision. Our value fits on the Polanyi-type, rate-enthalpy linear correlation ln(k/n) = (0.80 {+-} 0.05){Delta}H + (3.2 {+-} 0.8) that is found for the analogous reactions of other aqueous aliphatic alcohols with n equivalent abstractable H atoms. The existence of such a correlation and its large slope are interpreted as an indication of the mechanistic similarity of the H atom abstraction from {alpha}- and {beta}-carbon atoms in alcohols occurring through the late, product-like transition state. tert-Butyl alcohol is commonly contaminated by much more reactive secondary and primary alcohols (2-propanol, 2-butanol, ethanol, and methanol), whose content can be sufficient for nearly quantitative scavenging of the H atoms, skewing the H atom reactivity pattern, and explaining the disparity of the literature data on the H + (CH{sub 3}){sub 3}COH rate constant. The ubiquitous use of tert-butyl alcohol in pulse radiolysis for investigating H atom reactivity and the results of this work suggest that many other previously reported rate constants for the H atom, particularly the smaller ones, may be in jeopardy.

  13. Wet oxidation of high-concentration reactive dyes

    SciTech Connect (OSTI)

    Chen, G.; Lei, L.; Yue, P.L.

    1999-05-01

    Advanced oxidation methods were used to degrade reactive dyes at high concentrations in aqueous solutions. Wet peroxide oxidation (WPO) was found to be the best method in terms of the removal of color and total organic carbon (TOC). Reactive blue (Basilen Brilliant Blue P-3R) was chosen as a model dye for determining the suitable reaction conditions. The variables studied include reaction temperature, H{sub 2}O{sub 2} dosage, solution pH, dye concentration, and catalyst usage. The removal of TOC and color by wet oxidation is very sensitive to the reaction temperature. At 150 C, the removal of 77% TOC and 90% color was obtained in less than 30 min. The initial TOC removal rate is proportional to the H{sub 2}O{sub 2} dosage. The TOC removal is insignificant even when 50% of the stoichiometric amount of H{sub 2}O{sub 2} is used. No color change is observed until the dosage of H{sub 2}O{sub 2} is 100% of the stoichiometric amount. The color removal is closely related to TOC removal. When the pH of the solution is adjusted to 3.5, the dye degradation rate increases significantly. The rates of TOC and color removal are enhanced by using a Cu{sup 2+} catalyst. Another four reactive dyes, Procion Red PX-4B, Cibacron Yellow P-6GS, Cibacron Brown P-6R, and Procion Black PX-2R, were treated at 150 C using WPO. More than 80% TOC was removed from the solution in less than 15 min. The process can remove the colors of al these dyes except Procion Black PX-2R.

  14. Gas sampling system for reactive gas-solid mixtures

    DOE Patents [OSTI]

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1989-01-01

    An apparatus and method for sampling a gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extend in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  15. Gas sampling system for reactive gas-solid mixtures

    DOE Patents [OSTI]

    Daum, Edward D. (Alliance, OH); Downs, William (Alliance, OH); Jankura, Bryan J. (Mogadore, OH); McCoury, Jr., John M. (Mineral City, OH)

    1990-01-01

    An apparatus and method for sampling gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extends in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  16. Perspective on fossil power plant layup and reactivation

    SciTech Connect (OSTI)

    Tsou, J.L.

    1996-12-31

    In recent years, many utilities have developed excess generation capacity problems during period of low system load growth, particularly with new generation units coming on-line. System load studies may indicate that the situation is temporary and higher generation capacity will be needed in the near future. The objective of layup is to prevent component deterioration during the long shut down periods. This paper discusses equipment preservation practices in use by the electric utility industry and the advantages/disadvantages of various layup methods. Other issues related to plant layup and reactivation are also presented.

  17. Reactive multilayer synthesis of hard ceramic foils and films

    DOE Patents [OSTI]

    Makowiecki, Daniel M. (Livermore, CA); Holt, Joseph B. (San Jose, CA)

    1996-01-01

    A method for synthesizing hard ceramic materials such as carbides, borides nd aluminides, particularly in the form of coatings provided on another material so as to improve the wear and abrasion performance of machine tools, for example. The method involves the sputter deposition of alternating layers of reactive metals with layers of carbon, boron, or aluminum and the subsequent reaction of the multilayered structure to produce a dense crystalline ceramic. The material can be coated on a substrate or formed as a foil which can be coild as a tape for later use.

  18. Reactive Flash Volatilization of Solid, Nonvolatile Fuel - Energy

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

    Innovation Portal Biomass and Biofuels Biomass and Biofuels Find More Like This Return to Search Reactive Flash Volatilization of Solid, Nonvolatile Fuel DOE Grant Recipients University of Minnesota Contact University of Minnesota About This Technology <span id="Caption"><span id="ctl00_MainContentHolder_zoomimage_defaultCaption">Syngas or Synthesis Gas</span></span> Syngas or Synthesis Gas <span id="Caption"><span

  19. Method for preparing hydride configurations and reactive metal surfaces

    DOE Patents [OSTI]

    Silver, Gary L. (Centerville, OH)

    1988-08-16

    A method for preparing highly hydrogen-reactive surfaces on metals which normally require substantial heating, high pressures, or an extended induction period, which involves pretreatment of said surfaces with either a non-oxidizing acid or hydrogen gas to form a hydrogen-bearing coating on said surfaces, and subsequently heating said coated metal in the absence of moisture and oxygen for a period sufficient to decompose said coating and cooling said metal to room temperature. Surfaces so treated will react almost instantaneously with hydrogen gas at room temperature and low pressure. The method is particularly applicable to uranium, thorium, and lanthanide metals.

  20. New NIR Calibration Models Speed Biomass Composition and Reactivity Characterization

    SciTech Connect (OSTI)

    2015-09-01

    Obtaining accurate chemical composition and reactivity (measures of carbohydrate release and yield) information for biomass feedstocks in a timely manner is necessary for the commercialization of biofuels. This highlight describes NREL's work to use near-infrared (NIR) spectroscopy and partial least squares multivariate analysis to develop calibration models to predict the feedstock composition and the release and yield of soluble carbohydrates generated by a bench-scale dilute acid pretreatment and enzymatic hydrolysis assay. This highlight is being developed for the September 2015 Alliance S&T Board meeting.

  1. Spatial corrections for pulsed-neutron reactivity measurements.

    SciTech Connect (OSTI)

    Cao, Y.; Lee, J.; Nuclear Engineering Division; Univ. of Michigan

    2010-07-01

    For pulsed-neutron experiments performed in a subcritical reactor, the reactivity obtained from the area-ratio method is sensitive to detector positions. The spatial effects are induced by the presence of both the prompt neutron harmonics and the delayed neutron harmonics in the reactor. The traditional kinetics distortion factor is only limited to correcting the spatial effects caused by the fundamental prompt-{alpha} mode. In this paper, we derive spatial correction factors fp and fd to account for spatial effects induced by the prompt neutron harmonics and the delayed neutron harmonics, respectively. Our numerical simulations with the FX2-TH time-dependent multigroup diffusion code indicate that the high-order prompt neutron harmonics lead to significant spatial effects and cannot be neglected in calculating the spatial correction factors. The prompt spatial correction factor fp can be simply determined by the ratio of the normalized detector responses corresponding to the fundamental k-mode and the prompt neutron flux integrated over the pulse period. Thus, it is convenient to calculate and provides physically intuitive explanations on the spatial dependence of reactivity measured in the MUSE-4 experiments: overestimation of the subcriticality in regions close to the external neutron source and underestimation of the subcriticality away from the source but within the fuel region.

  2. End-Member Formulation of Solid Solutions and Reactive Transport

    SciTech Connect (OSTI)

    Lichtner, Peter C.

    2015-09-01

    A model for incorporating solid solutions into reactive transport equations is presented based on an end-member representation. Reactive transport equations are solved directly for the composition and bulk concentration of the solid solution. Reactions of a solid solution with an aqueous solution are formulated in terms of an overall stoichiometric reaction corresponding to a time-varying composition and exchange reactions, equivalent to reaction end-members. Reaction rates are treated kinetically using a transition state rate law for the overall reaction and a pseudo-kinetic rate law for exchange reactions. The composition of the solid solution at the onset of precipitation is assumed to correspond to the least soluble composition, equivalent to the composition at equilibrium. The stoichiometric saturation determines if the solid solution is super-saturated with respect to the aqueous solution. The method is implemented for a simple prototype batch reactor using Mathematica for a binary solid solution. Finally, the sensitivity of the results on the kinetic rate constant for a binary solid solution is investigated for reaction of an initially stoichiometric solid phase with an undersaturated aqueous solution.

  3. Hybrid nuclear reactor grey rod to obtain required reactivity worth

    DOE Patents [OSTI]

    Miller, John V. (Munhall, PA); Carlson, William R. (Scott Township, Allegheny County, PA); Yarbrough, Michael B. (Hempfield Township, Westmoreland County, PA)

    1991-01-01

    Hybrid nuclear reactor grey rods are described, wherein geometric combinations of relatively weak neutron absorber materials such as stainless steel, zirconium or INCONEL, and relatively strong neutron absorber materials, such as hafnium, silver-indium cadmium and boron carbide, are used to obtain the reactivity worths required to reach zero boron change load follow. One embodiment includes a grey rod which has combinations of weak and strong neutron absorber pellets in a stainless steel cladding. The respective pellets can be of differing heights. A second embodiment includes a grey rod with a relatively thick stainless steel cladding receiving relatively strong neutron absorber pellets only. A third embodiment includes annular relatively weak netron absorber pellets with a smaller diameter pellet of relatively strong absorber material contained within the aperture of each relatively weak absorber pellet. The fourth embodiment includes pellets made of a homogeneous alloy of hafnium and a relatively weak absorber material, with the percentage of hafnium chosen to obtain the desired reactivity worth.

  4. Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.

    SciTech Connect (OSTI)

    Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

    2012-02-01

    In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This

  5. Tritium Gas Stream Scrubbing using In-situ Reactive Materials | Department

    Office of Environmental Management (EM)

    of Energy Stream Scrubbing using In-situ Reactive Materials Tritium Gas Stream Scrubbing using In-situ Reactive Materials Presentation from the 36th Tritium Focus Group Meeting held in Los Alamos, New Mexico, November 3-5, 2015. PDF icon Tritium Gas Stream Scrubbing using In-situ Reactive Materials More Documents & Publications Effect of Various Impurities on the Hydrogen Absorption on SAES ST198 AVTA: Oil Bypass Filter Specifications and Test Procedures Vehicle Technologies Office Merit

  6. Surprising differences in the reactivity of cyanoaromatic radical anions generated by photoinduced electron transfer

    SciTech Connect (OSTI)

    Kellett, M.A.; Whitten, D.G. ); Gould, I.R. ); Bergmark, W.R. )

    1991-01-02

    In this paper, the authors report some studies that indicate that the reactivity of photogenerated cyanoaromatic anion radicals is strongly affected by the medium in which they are generated; interestingly they report conditions under which potentially reactive anion radicals of strongly affected by the medium in which they are generated; interestingly they report conditions under which potentially reactive anion radicals of DCA and 2,6,9,10-tetracyanoanthracene (TCA) can be the stable end products of photoinduced redox reactions.

  7. Impact of EGR on Soot Nanostructure and Reactivity | Department of Energy

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

    EGR on Soot Nanostructure and Reactivity Impact of EGR on Soot Nanostructure and Reactivity Presentation given at the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007, Detroit, Michigan. Sponsored by the U.S. Department of Energy's (DOE) Office of FreedomCAR and Vehicle Technologies (OFCVT). PDF icon deer07_boehman.pdf More Documents & Publications Fuel Impacts on Soot Nanostructure and Reactivity Effect of Alternative Fuels on Soot Properties

  8. Experimental Evidence for Self-Limiting Reactive Flow through a Fractured

    Office of Scientific and Technical Information (OSTI)

    Cement Core: Implications for Time-Dependent Wellbore Leakage (Journal Article) | SciTech Connect Experimental Evidence for Self-Limiting Reactive Flow through a Fractured Cement Core: Implications for Time-Dependent Wellbore Leakage Citation Details In-Document Search Title: Experimental Evidence for Self-Limiting Reactive Flow through a Fractured Cement Core: Implications for Time-Dependent Wellbore Leakage We present a set of reactive transport experiments in cement fractures. The

  9. Performance of a Permeable Reactive Barrier Using Granular Zero-Valent

    Energy Savers [EERE]

    Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site | Department of Energy of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site Performance of a Permeable Reactive Barrier Using Granular Zero-Valent Iron: FY 2004 Annual Report Durango, Colorado, Disposal Site PDF icon Performance of a

  10. Method of measuring reactive acoustic power density in a fluid

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1985-09-03

    A method for determining reactive acoustic power density level and its direction in a fluid using a single sensor is disclosed. In the preferred embodiment, an apparatus for conducting the method, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas. 5 figs.

  11. Method of measuring reactive acoustic power density in a fluid

    DOE Patents [OSTI]

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1985-01-01

    A method for determining reactive acoustic power density level and its direction in a fluid using a single sensor is disclosed. In the preferred embodiment, an apparatus for conducting the method, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.

  12. IONIC LIQUIDS: RADIATION CHEMISTRY, SOLVATION DYNAMICS AND REACTIVITY PATTERNS.

    SciTech Connect (OSTI)

    WISHART,J.F.

    2007-10-01

    energy production, nuclear fuel and waste processing, improving the efficiency and safety of industrial chemical processes, and pollution prevention. ILs are generally nonvolatile, noncombustible, highly conductive, recyclable and capable of dissolving a wide variety of materials. They are finding new uses in chemical synthesis, catalysis, separations chemistry, electrochemistry and other areas. Ionic liquids have dramatically different properties compared to conventional molecular solvents, and they provide a new and unusual environment to test our theoretical understanding of charge transfer and other reactions. We are interested in how IL properties influence physical and dynamical processes that determine the stability and lifetimes of reactive intermediates and thereby affect the courses of chemical reactions and product distributions. Successful use of ionic liquids in radiation-filled environments, where their safety advantages could be significant, requires an understanding of ionic liquid radiation chemistry. For example, characterizing the primary steps of IL radiolysis will reveal radiolytic degradation pathways and suggest ways to prevent them or mitigate their effects on the properties of the material. An understanding of ionic liquid radiation chemistry will also facilitate pulse radiolysis studies of general chemical reactivity in ILs, which will aid in the development of applications listed above. Very early in our radiolysis studies it became evident that slow solvation dynamics of the excess electron in ILs (which vary over a wide viscosity range) increases the importance of pre-solvated electron reactivity and consequently alters product distributions. Parallel studies of IL solvation phenomena using coumarin-153 dynamic Stokes shifts and polarization anisotropy decay rates are done to compare with electron solvation studies and to evaluate the influence of ILs on charge transport processes. Methods. Picosecond pulse radiolysis studies at BNL's Laser-Electron Accelerator Facility (LEAF) are used to identify reactive species in ionic liquids and measure their solvation and reaction rates. We and our collaborators (R. Engel (Queens College, CUNY) and S. Lall-Ramnarine, (Queensborough CC, CUNY)) develop and characterize new ionic liquids specifically designed for our radiolysis and solvation dynamics studies. IL solvation and rotational dynamics are measured by TCSPC and fluorescence upconversion measurements in the laboratory of E. W. Castner at Rutgers Univ. Investigations of radical species in irradiated ILs are carried out at ANL by I. Shkrob and S. Chemerisov using EPR spectroscopy. Diffusion rates are obtained by PGSE NMR in S. Greenbaum's lab at Hunter College, CUNY and S. Chung's lab at William Patterson U. Professor Mark Kobrak of CUNY Brooklyn College performs molecular dynamics simulations of solvation processes. A collaboration with M. Dietz and coworkers at ANL is centered around the properties and radiolytic behavior of ionic liquids for nuclear separations. Collaborations with C. Reed (UC Riverside), D. Gabel (U. Bremen) and J. Davis (U. South Alabama) are aimed at characterizing the radiolytic and other properties of borated ionic liquids, which could be used to make fissile material separations processes inherently safe from criticality accidents.

  13. Ionic Liquids: Radiation Chemistry, Solvation Dynamics and Reactivity Patterns

    SciTech Connect (OSTI)

    Wishart,J.F.

    2008-09-29

    Ionic liquids (ILs) are a rapidly expanding family of condensed-phase media with important applications in energy production, nuclear fuel and waste processing, improving the efficiency and safety of industrial chemical processes, and pollution prevention. ILs are generally nonvolatile, noncombustible, highly conductive, recyclable and capable of dissolving a wide variety of materials. They are finding new uses in chemical synthesis, catalysis, separations chemistry, electrochemistry and other areas. Ionic liquids have dramatically different properties compared to conventional molecular solvents, and they provide a new and unusual environment to test our theoretical understanding of charge transfer and other reactions. We are interested in how IL properties influence physical and dynamical processes that determine the stability and lifetimes of reactive intermediates and thereby affect the courses of chemical reactions and product distributions. Successful use of ionic liquids in radiation-filled environments, where their safety advantages could be significant, requires an understanding of ionic liquid radiation chemistry. For example, characterizing the primary steps of IL radiolysis will reveal radiolytic degradation pathways and suggest ways to prevent them or mitigate their effects on the properties of the material. An understanding of ionic liquid radiation chemistry will also facilitate pulse radiolysis studies of general chemical reactivity in ILs, which will aid in the development of applications listed above. Very early in our radiolysis studies it became evident that slow solvation dynamics of the excess electron in ILs (which vary over a wide viscosity range) increases the importance of pre-solvated electron reactivity and consequently alters product distributions. Parallel studies of IL solvation phenomena using coumarin-153 dynamic Stokes shifts and polarization anisotropy decay rates are done to compare with electron solvation studies and to evaluate the influence of ILs on charge transport processes. Picosecond pulse radiolysis studies at BNL's Laser-Electron Accelerator Facility (LEAF) are used to identify reactive species in ionic liquids and measure their solvation and reaction rates. We and our collaborators (R. Engel (Queens College, CUNY) and S. Lall-Ramnarine, (Queensborough CC, CUNY)) develop and characterize new ionic liquids specifically designed for our radiolysis and solvation dynamics studies. IL solvation and rotational dynamics are measured by TCSPC and fluorescence upconversion measurements in the laboratory of E. W. Castner at Rutgers Univ. Investigations of radical species in irradiated ILs are carried out at ANL by I. Shkrob and S. Chemerisov using EPR spectroscopy. Diffusion rates are obtained by PGSE NMR in S. Greenbaum's lab at Hunter College, CUNY and S. Chung's lab at William Patterson U. Professor Mark Kobrak of CUNY Brooklyn College performs molecular dynamics simulations of solvation processes. A collaboration with M. Dietz at U. Wisc. Milwaukee is centered around the properties and radiolytic behavior of ionic liquids for nuclear separations. Collaborations with C. Reed (UC Riverside), D. Gabel (U. Bremen) and J. Davis (U. South Alabama) are aimed at characterizing the radiolytic and other properties of borated ionic liquids, which could be used to make fissile material separations processes inherently safe from criticality accidents.

  14. Transparent electrical conducting films by activated reactive evaporation

    DOE Patents [OSTI]

    Bunshah, Rointan (Los Angeles, CA); Nath, Prem (Troy, MI)

    1982-01-01

    Process and apparatus for producing transparent electrical conducting thin films by activated reactive evaporation. Thin films of low melting point metals and alloys, such as indium oxide and indium oxide doped with tin, are produced by physical vapor deposition. The metal or alloy is vaporized by electrical resistance heating in a vacuum chamber, oxygen and an inert gas such as argon are introduced into the chamber, and vapor and gas are ionized by a beam of low energy electrons in a reaction zone between the resistance heater and the substrate. There is a reaction between the ionized oxygen and the metal vapor resulting in the metal oxide which deposits on the substrate as a thin film which is ready for use without requiring post deposition heat treatment.

  15. Anode reactive bleed and injector shift control strategy

    DOE Patents [OSTI]

    Cai, Jun [Rochester, NY; Chowdhury, Akbar [Pittsford, NY; Lerner, Seth E [Honeoye Falls, NY; Marley, William S [Rush, NY; Savage, David R [Rochester, NY; Leary, James K [Rochester, NY

    2012-01-03

    A system and method for correcting a large fuel cell voltage spread for a split sub-stack fuel cell system. The system includes a hydrogen source that provides hydrogen to each split sub-stack and bleed valves for bleeding the anode side of the sub-stacks. The system also includes a voltage measuring device for measuring the voltage of each cell in the split sub-stacks. The system provides two levels for correcting a large stack voltage spread problem. The first level includes sending fresh hydrogen to the weak sub-stack well before a normal reactive bleed would occur, and the second level includes sending fresh hydrogen to the weak sub-stack and opening the bleed valve of the other sub-stack when the cell voltage spread is close to stack failure.

  16. The Reactivity of Energetic Materials At Extreme Conditions

    SciTech Connect (OSTI)

    Fried, L E

    2006-10-23

    Energetic materials are unique for having a strong exothermic reactivity, which has made them desirable for both military and commercial applications. Energetic materials are commonly divided into high explosives, propellants, and pyrotechnics. We will focus on high explosive (HE) materials here, although there is a great deal of commonality between the classes of energetic materials. Although the history of HE materials is long, their condensed-phase properties are poorly understood. Understanding the condensed-phase properties of HE materials is important for determining stability and performance. Information regarding HE material properties (for example, the physical, chemical, and mechanical behaviors of the constituents in plastic-bonded explosive, or PBX, formulations) is necessary for efficiently building the next generation of explosives as the quest for more powerful energetic materials (in terms of energy per volume) moves forward. In modeling HE materials there is a need to better understand the physical, chemical, and mechanical behaviors from fundamental theoretical principles. Among the quantities of interest in plastic-bonded explosives (PBXs), for example, are thermodynamic stabilities, reaction kinetics, equilibrium transport coefficients, mechanical moduli, and interfacial properties between HE materials and the polymeric binders. These properties are needed (as functions of stress state and temperature) for the development of improved micro-mechanical models, which represent the composite at the level of grains and binder. Improved micro-mechanical models are needed to describe the responses of PBXs to dynamic stress or thermal loading, thus yielding information for use in developing continuum models. Detailed descriptions of the chemical reaction mechanisms of condensed energetic materials at high densities and temperatures are essential for understanding events that occur at the reactive front under combustion or detonation conditions. Under shock conditions, for example, energetic materials undergo rapid heating to a few thousand degrees and are subjected to a compression of hundreds of kilobars, resulting in almost 30% volume reduction. Complex chemical reactions are thus initiated, in turn releasing large amounts of energy to sustain the detonation process. Clearly, understanding of the various chemical events at these extreme conditions is essential in order to build predictive material models. Scientific investigations into the reactive process have been undertaken over the past two decades. However, the sub-{micro}s time scale of explosive reactions, in addition to the highly exothermic conditions of an explosion, make experimental investigation of the decomposition pathways difficult at best. More recently, new computational approaches to investigate condensed-phase reactivity in energetic materials have been developed. Here we focus on two different approaches to condensed-phase reaction modeling: chemical equilibrium methods and atomistic modeling of condensed-phase reactions. These are complementary approaches to understanding the chemical reactions of high explosives. Chemical equilibrium modeling uses a highly simplified thermodynamic picture of the reaction process, leading to a convenient and predictive model of detonation and other decomposition processes. Chemical equilibrium codes are often used in the design of new materials, both at the level of synthesis chemistry and formulation. Atomistic modeling is a rapidly emerging area. The doubling of computational power approximately every 18 months has made atomistic condensed-phase modeling more feasible. Atomistic calculations employ far fewer empirical parameters than chemical equilibrium calculations. Nevertheless, the atomistic modeling of chemical reactions requires an accurate global Born-Oppenheimer potential energy surface. Traditionally, such a surface is constructed by representing the potential energy surface with an analytical fit. This approach is only feasible for simple chemical reactions involving a small number of atoms

  17. Properties of reactive oxygen species by quantum Monte Carlo

    SciTech Connect (OSTI)

    Zen, Andrea; Trout, Bernhardt L.; Guidoni, Leonardo

    2014-07-07

    The electronic properties of the oxygen molecule, in its singlet and triplet states, and of many small oxygen-containing radicals and anions have important roles in different fields of chemistry, biology, and atmospheric science. Nevertheless, the electronic structure of such species is a challenge for ab initio computational approaches because of the difficulties to correctly describe the statical and dynamical correlation effects in presence of one or more unpaired electrons. Only the highest-level quantum chemical approaches can yield reliable characterizations of their molecular properties, such as binding energies, equilibrium structures, molecular vibrations, charge distribution, and polarizabilities. In this work we use the variational Monte Carlo (VMC) and the lattice regularized Monte Carlo (LRDMC) methods to investigate the equilibrium geometries and molecular properties of oxygen and oxygen reactive species. Quantum Monte Carlo methods are used in combination with the Jastrow Antisymmetrized Geminal Power (JAGP) wave function ansatz, which has been recently shown to effectively describe the statical and dynamical correlation of different molecular systems. In particular, we have studied the oxygen molecule, the superoxide anion, the nitric oxide radical and anion, the hydroxyl and hydroperoxyl radicals and their corresponding anions, and the hydrotrioxyl radical. Overall, the methodology was able to correctly describe the geometrical and electronic properties of these systems, through compact but fully-optimised basis sets and with a computational cost which scales as N{sup 3} ? N{sup 4}, where N is the number of electrons. This work is therefore opening the way to the accurate study of the energetics and of the reactivity of large and complex oxygen species by first principles.

  18. Reactivity of amine antioxidants relative to OH and anti e

    SciTech Connect (OSTI)

    Minkhadzhidinova, D.R.; Nikiforov, G.A.; Khrapova, N.G.; Sharpatyi, V.A.

    1986-06-20

    An ESR study was carried out on the reactivity of various types of amines relative to OH/sup ./ and anti e. The selection of these compounds having anti-oxidant properties was also based on the circumstance that amine molecules contain a set of functional groups which may be potential sites for the attack of both OH and anti e radicals. A sample of 6 M H/sub 3/PO/sub 4/ was used for the matrix solutions and forms a glass upon rapid insertion into liquid nitrogen. The phosphoric acid solutions of these compounds taken in concentrations from 0.025 to 0.05 M were flushed with argon to remove oxygen. Ampules containing the solutions were inserted into liquid nitrogen and irradiated from a cobalt source. The ESR spectra of the irradiated solutions clearly show the components of the atomic hydrogen doublet with a = 50 mT and of H/sub 2/PO/sub 4//sup ./ radicals in the central region of the spectrum.

  19. LX-17 Corner-Turning and Reactive Flow Failure

    SciTech Connect (OSTI)

    Souers, P C; Andreski, H; Cook III, C F; Garza, R; Pastrone, R; Phillips, D; Roeske, F; Vitello, P; Molitoris, J

    2004-03-11

    We have performed a series of highly-instrumented experiments examining corner-turning of detonation. A TATB booster is inset 15 mm into LX-17 (92.5% TATB, 7.5% kel-F) so that the detonation must turn a right angle around an air well. An optical pin located at the edge of the TATB gives the start time of the corner-turn. The breakout time on the side and back edges is measured with streak cameras. Three high-resolution X-ray images were taken on each experiment to examine the details of the detonation. We have concluded that the detonation cannot turn the corner and subsequently fails, but the shock wave continues to propagate in the unreacted explosive, leaving behind a dead zone. The detonation front farther out from the corner slowly turns and eventually reaches the air well edge 180{sup o} from its original direction. The dead zone is stable and persists 7.7 {micro}s after the corner-turn, although it has drifted into the original air well area. Our regular reactive flow computer models sometimes show temporary failure but they recover quickly and are unable to model the dead zones. We present a failure model that cuts off the reaction rate below certain detonation velocities and reproduces the qualitative features of the corner-turning failure.

  20. Predictive modeling of reactive wetting and metal joining.

    SciTech Connect (OSTI)

    van Swol, Frank B.

    2013-09-01

    The performance, reproducibility and reliability of metal joints are complex functions of the detailed history of physical processes involved in their creation. Prediction and control of these processes constitutes an intrinsically challenging multi-physics problem involving heating and melting a metal alloy and reactive wetting. Understanding this process requires coupling strong molecularscale chemistry at the interface with microscopic (diffusion) and macroscopic mass transport (flow) inside the liquid followed by subsequent cooling and solidification of the new metal mixture. The final joint displays compositional heterogeneity and its resulting microstructure largely determines the success or failure of the entire component. At present there exists no computational tool at Sandia that can predict the formation and success of a braze joint, as current capabilities lack the ability to capture surface/interface reactions and their effect on interface properties. This situation precludes us from implementing a proactive strategy to deal with joining problems. Here, we describe what is needed to arrive at a predictive modeling and simulation capability for multicomponent metals with complicated phase diagrams for melting and solidification, incorporating dissolutive and composition-dependent wetting.

  1. Etching radical controlled gas chopped deep reactive ion etching

    DOE Patents [OSTI]

    Olynick, Deidre; Rangelow, Ivo; Chao, Weilun

    2013-10-01

    A method for silicon micromachining techniques based on high aspect ratio reactive ion etching with gas chopping has been developed capable of producing essentially scallop-free, smooth, sidewall surfaces. The method uses precisely controlled, alternated (or chopped) gas flow of the etching and deposition gas precursors to produce a controllable sidewall passivation capable of high anisotropy. The dynamic control of sidewall passivation is achieved by carefully controlling fluorine radical presence with moderator gasses, such as CH.sub.4 and controlling the passivation rate and stoichiometry using a CF.sub.2 source. In this manner, sidewall polymer deposition thicknesses are very well controlled, reducing sidewall ripples to very small levels. By combining inductively coupled plasmas with controlled fluorocarbon chemistry, good control of vertical structures with very low sidewall roughness may be produced. Results show silicon features with an aspect ratio of 20:1 for 10 nm features with applicability to nano-applications in the sub-50 nm regime. By comparison, previous traditional gas chopping techniques have produced rippled or scalloped sidewalls in a range of 50 to 100 nm roughness.

  2. Installation of reactive metals groundwater collection and treatment systems

    SciTech Connect (OSTI)

    Hopkins, J.K.; Primrose, A.L.; Vogan, J.; Uhland, J.

    1998-07-01

    Three groundwater plumes contaminated with volatile organic compounds (VOCs) and radionuclides at the Rocky Flats Environmental Technology Site are scheduled for remediation by 1999 based on the Rocky Flats Cleanup Agreement (RFCA) (DOE, 1996). These three plumes are among the top 20 environmental cleanup sites at Rocky Flats. One of these plumes, the Mound Site Plume, is derived from a previous drum storage area, and daylights as seeps near the South Walnut Creek drainage. Final design for remediation of the Mound Site Plume has been completed based on use of reactive metals to treat the contaminated groundwater, and construction is scheduled for early 1998. The two other plumes, the 903 Pad/Ryan`s Pit and the East Trenches Plumes, are derived from VOCs either from drums that leaked or that were disposed of in trenches. These two plumes are undergoing characterization and conceptual design in 1998 and construction is scheduled in 1999. The contaminants of concern in these plumes are tetrachloroethene, trichloroethene, carbon tetrachloride and low levels of uranium and americium.

  3. Apparatus for continuously referenced analysis of reactive components in solution

    DOE Patents [OSTI]

    Bostick, William D. (Oak Ridge, TN); Denton, Mark S. (Oak Ridge, TN); Dinsmore, Stanley R. (Norris, TN)

    1981-01-01

    A continuously referenced apparatus for measuring the concentration of a reactive chemical species in solution comprises in combination conduit means for introducing a sample solution, means for introducing one or more reactants into a sample solution, a reaction zone in fluid communication with said conduit means wherein a first chemical reaction occurs between said species and reactants, and a stream separator disposed within the conduit means for separating the sample solution into a sample stream and a reference stream. An enzymatic reactor is disposed in fluid communication with only the sample stream wherein a second reaction takes place between the said reactants, species, and reactor enzymes causing the consumption or production of an indicator species in just the sample stream. Measurement means such as a photometric system are disposed in communication with the sample and reference streams, and the outputs of the measurement means are compared to provide a blanked measurement of the concentration of indicator species. A peristaltic pump is provided to equalize flow through the apparatus by evacuation. The apparatus is particularly suitable for measurement of isoenzymes in body tissues or fluids.

  4. Reactivity of iron-bearing minerals and CO2 sequestration: A multi-disciplinary experimental approach

    SciTech Connect (OSTI)

    Schoonen, Martin A.

    2014-12-22

    The reactivity of sandstones was studied under conditions relevant to the injection of supercritical carbon dioxide in the context of carbon geosequestration. The emphasis of the study was on the reactivity of iron-bearing minerals when exposed to supercritical CO2 (scCO2) and scCO2 with commingled aqueous solutions containing H2S and/or SO2. Flow through and batch experiments were conducted. Results indicate that sandstones, irrespective of their mineralogy, are not reactive when exposed to pure scCO2 or scCO2 with commingled aqueous solutions containing H2S and/or SO2 under conditions simulating the environment near the injection point (flow through experiments). However, sandstones are reactive under conditions simulating the edge of the injected CO2 plume or ahead of the plume (batch experiments). Sandstones containing hematite (red sandstone) are particularly reactive. The composition of the reaction products is strongly dependent on the composition of the aqueous phase. The presence of dissolved sulfide leads to the conversion of hematite into pyrite and siderite. The relative amount of the pyrite and siderite is influenced by the ionic strength of the solution. Little reactivity is observed when sulfite is present in the aqueous phase. Sandstones without hematite (grey sandstones) show little reactivity regardless of the solution composition.

  5. Final Report- Rejuvenating Permeable Reactive Barriers by Chemical Flushing, U.S. Environmental Protection Agency Region 8 Support

    Broader source: Energy.gov [DOE]

    Final Report - Rejuvenating Permeable Reactive Barriers by Chemical Flushing, U.S. Environmental Protection Agency Region 8 Support

  6. Review of Reactivity Experiments for Lithium Ternary Alloys

    SciTech Connect (OSTI)

    Jolodosky, A.; Bolind, A.; Fratoni, M.

    2015-09-28

    Lithium is often the preferred choice as breeder and coolant in fusion blankets as it offers high tritium breeding, excellent heat transfer and corrosion properties, and most importantly, it has very high tritium solubility and results in very low levels of tritium permeation throughout the facility infrastructure. However, lithium metal vigorously reacts with air and water and exacerbates plant safety concerns. Consequently, Lawrence Livermore National Laboratory (LLNL) is attempting to develop a lithium-based alloy—most likely a ternary alloy—which maintains the beneficial properties of lithium (e.g. high tritium breeding and solubility) while reducing overall flammability concerns for use in the blanket of an inertial fusion energy (IFE) power plant. The LLNL concept employs inertial confinement fusion (ICF) through the use of lasers aimed at an indirect-driven target composed of deuterium-tritium fuel. The fusion driver/target design implements the same physics currently experimented at the National Ignition Facility (NIF). The plant uses lithium in both the primary coolant and blanket; therefore, lithium related hazards are of primary concern. Reducing chemical reactivity is the primary motivation for the development of new lithium alloys, and it is therefore important to come up with proper ways to conduct experiments that can physically study this phenomenon. This paper will start to explore this area by outlining relevant past experiments conducted with lithium/air reactions and lithium/water reactions. Looking at what was done in the past will then give us a general idea of how we can setup our own experiments to test a variety of lithium alloys.

  7. Kinetics and mechanisms of reactions involving small aromatic reactive intermediates

    SciTech Connect (OSTI)

    Lin, M.C.

    1993-12-01

    Small aromatic radicals such as C{sub 6}H{sub 5}, C{sub 6}H{sub 5}O and C{sub 6}H{sub 4} are key prototype species of their homologs. C{sub 6}H{sub 5} and its oxidation product, C{sub 6}H{sub 5}O are believed to be important intermediates which play a pivotal role in hydrocarbon combustion, particularly with regard to soot formation. Despite their fundamental importance, experimental data on the reaction mechanisms and reactivities of these species are very limited. For C{sub 6}H{sub 5}, most kinetic data except its reactions with NO and NO{sub 2}, were obtained by relative rate measurements. For C{sub 6}H{sub 5}O, the authors have earlier measured its fragmentation reaction producing C{sub 5}H{sub 5} + CO in shock waves. For C{sub 6}H{sub 4}, the only rate constant measured in the gas phase is its recombination rate at room temperature. The authors have proposed to investigate systematically the kinetics and mechanisms of this important class of molecules using two parallel laser diagnostic techniques--laser resonance absorption (LRA) and resonance enhanced multiphoton ionization mass spectrometry (REMPI/MS). In the past two years, study has been focused on the development of a new multipass adsorption technique--the {open_quotes}cavity-ring-down{close_quotes} technique for kinetic applications. The preliminary results of this study appear to be quite good and the sensitivity of the technique is at least comparable to that of the laser-induced fluorescence method.

  8. The evaluation of the Nippon Steel Corporation reactivity and post-reaction-strength test for coke

    SciTech Connect (OSTI)

    Not Available

    1980-12-01

    A systematic investigation was made of the factors influencing the reactivity of coke, including test temperature, coke structural properties, mineral inclusions and additives, and the inert content of the charge.

  9. In-Cylinder Mechanisms of PCI Heat-Release Rate Control by Fuel Reactivity Stratification

    Broader source: Energy.gov [DOE]

    Explores in-cylinder mechanisms by which fuel reactivity stratification via a two fuel system affects premixed charge compression ignition heat release rate to achieve diesel-like efficiency

  10. Static reactive power compensators for high-voltage power systems. Final report

    SciTech Connect (OSTI)

    Not Available

    1981-04-01

    A study conducted to summarize the role of static reactive power compensators for high voltage power system applications is described. This information should be useful to the utility system planning engineer in applying static var systems (SVS) to high voltage as (HVAC) systems. The static var system is defined as a form of reactive power compensator. The general need for reactive power compensation in HVAC systems is discussed, and the static var system is compared to other devices utilized to provide reactive power compensation. Examples are presented of applying SVS for specific functions, such as the prevention of voltage collapse. The operating principles of commercially available SVS's are discussed in detail. The perormance and active power loss characteristics of SVS types are compared.

  11. ORNL/CP-97155 Instantaneous Reactive Power and Power Factor of

    Office of Scientific and Technical Information (OSTI)

    97155 Instantaneous Reactive Power and Power Factor of Instantaneous Phasor s ' 4 . L;, Oak Ridge National Laboratory* P f Senior Member &Eb "'ii Lf .. John S. Hsu 4- p d Post ...

  12. Assessment of the Economic Potential of Microgrids for Reactive Power Supply

    SciTech Connect (OSTI)

    Appen, Jan von; Marnay, Chris; Stadler, Michael; Momber, Ilan; Klapp, David; Scheven, Alexander von

    2011-05-01

    As power generation from variable distributed energy resources (DER) grows, energy flows in the network are changing, increasing the requirements for ancillary services, including voltage support. With the appropriate power converter, DER can provide ancillary services such as frequency control and voltage support. This paper outlines the economic potential of DERs coordinated in a microgrid to provide reactive power and voltage support at its point of common coupling. The DER Customer Adoption Model assesses the costs of providing reactive power, given local utility rules. Depending on the installed DER, the cost minimizing solution for supplying reactive power locally is chosen. Costs include the variable cost of the additional losses and the investment cost of appropriately over-sizing converters or purchasing capacitors. A case study of a large health care building in San Francisco is used to evaluate different revenue possibilities of creating an incentive for microgrids to provide reactive power.

  13. Sub-picosecond IR study of the reactive intermediate in an alkane...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Sub-picosecond IR study of the reactive intermediate in an alkane C-H bond activation reaction by CpRh(CO)2 Citation Details In-Document Search Title: ...

  14. Molten salt extraction of transuranic and reactive fission products from used uranium oxide fuel

    DOE Patents [OSTI]

    Herrmann, Steven Douglas

    2014-05-27

    Used uranium oxide fuel is detoxified by extracting transuranic and reactive fission products into molten salt. By contacting declad and crushed used uranium oxide fuel with a molten halide salt containing a minor fraction of the respective uranium trihalide, transuranic and reactive fission products partition from the fuel to the molten salt phase, while uranium oxide and non-reactive, or noble metal, fission products remain in an insoluble solid phase. The salt is then separated from the fuel via draining and distillation. By this method, the bulk of the decay heat, fission poisoning capacity, and radiotoxicity are removed from the used fuel. The remaining radioactivity from the noble metal fission products in the detoxified fuel is primarily limited to soft beta emitters. The extracted transuranic and reactive fission products are amenable to existing technologies for group uranium/transuranic product recovery and fission product immobilization in engineered waste forms.

  15. Phase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical Flushing

    Broader source: Energy.gov [DOE]

    Final ReportPhase II: Performance Evaluation of Permeable Reactive Barriers and Potential for Rejuvenation by Chemical FlushingU. S. Environmental Protection Agency Region 8 SupportJanuary 2004

  16. Influence of calcite on uranium(VI) reactive transport in the groundwater–river mixing zone

    SciTech Connect (OSTI)

    Ma, Rui; Liu, Chongxuan; Greskowiak, Janek; Prommer, Henning; Zachara, John M.; Zheng, Chunmiao

    2014-01-23

    Calcite is an important mineral that can affect uranyl reactive transport in subsurface sediments. This study investigated the distribution of calcite and its influence on uranyl adsorption and reactive transport in the groundwater-river mixing zone at US Hanford 300A, Washington State. Simulations using a 2D reactive transport model under field-relevant hydrogeochemical conditions revealed a complex distribution of calcite concentration as a result of dynamic groundwater-river interactions. The calcite concentration distribution in turn affected the spatial and temporal changes in aqueous carbonate, calcium, and pH, which subsequently influenced U(VI) mobility and discharge rates into the river. The results implied that calcite distribution and its concentration dynamics is an important consideration for field characterization, monitoring, and reactive transport prediction.

  17. Photoisomerization and photodissociation dynamics of reactive free radicals

    SciTech Connect (OSTI)

    Bise, Ryan T.

    2000-08-24

    The photofragmentation pathways of chemically reactive free radicals have been examined using the technique of fast beam photofragment translational spectroscopy. Measurements of the photodissociation cross-sections, product branching ratios, product state energy distributions, and angular distributions provide insight into the excited state potential energy surfaces and nonadiabatic processes involved in the dissociation mechanisms. Photodissociation spectroscopy and dynamics of the predissociative {tilde A}{sup 2}A{sub 1} and {tilde B}{sup 2}A{sub 2} states of CH{sub 3}S have been investigated. At all photon energies, CH{sub 3} + S({sup 3}P{sub j}), was the main reaction channel. The translational energy distributions reveal resolved structure corresponding to vibrational excitation of the CH{sub 3} umbrella mode and the S({sup 3}P{sub j}) fine-structure distribution from which the nature of the coupled repulsive surfaces is inferred. Dissociation rates are deduced from the photofragment angular distributions, which depend intimately on the degree of vibrational excitation in the C-S stretch. Nitrogen combustion radicals, NCN, CNN and HNCN have also been studied. For all three radicals, the elimination of molecular nitrogen is the primary reaction channel. Excitation to linear excited triplet and singlet electronic states of the NCN radical generates resolved vibrational structure of the N{sub 2} photofragment. The relatively low fragment rotational excitation suggests dissociation via a symmetric C{sub 2V} transition state. Resolved vibrational structure of the N{sub 2} photofragment is also observed in the photodissociation of the HNCN radical. The fragment vibrational and rotational distributions broaden with increased excitation energy. Simple dissociation models suggest that the HNCN radical isomerizes to a cyclic intermediate (c-HCNN) which then dissociates via a tight cyclic transition state. In contrast to the radicals mentioned above, resolved vibrational structure was not observed for the ICNN radical due to extensive fragment rotational excitation, suggesting that intermediate bent states are strongly coupled along the dissociation pathway. The measurements performed in this Thesis have additionally refined the heats of formation and bond dissociation energies of these radicals and have unambiguously confirmed and added to the known electronic spectroscopy.

  18. Improved etch resistance of ZEP 520A in reactive ion etching through heat

    Office of Scientific and Technical Information (OSTI)

    and ultraviolet light treatment. (Journal Article) | SciTech Connect Improved etch resistance of ZEP 520A in reactive ion etching through heat and ultraviolet light treatment. Citation Details In-Document Search Title: Improved etch resistance of ZEP 520A in reactive ion etching through heat and ultraviolet light treatment. The authors have developed a treatment process to improve the etch resistance of an electron beam lithography resist (ZEP 520A) to allow direct pattern transfer from the

  19. Long-Term Stewardship of Mixed Wastes: Passive Reactive Barriers for

    Office of Scientific and Technical Information (OSTI)

    Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal, and Radionuclide Contaminants (Technical Report) | SciTech Connect Long-Term Stewardship of Mixed Wastes: Passive Reactive Barriers for Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal, and Radionuclide Contaminants Citation Details In-Document Search Title: Long-Term Stewardship of Mixed Wastes: Passive Reactive Barriers for Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal, and

  20. Long-term Stewardship of Mixed Wastes: Passive Reactive Barriers for

    Office of Scientific and Technical Information (OSTI)

    Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal and Radioactive (Technical Report) | SciTech Connect Long-term Stewardship of Mixed Wastes: Passive Reactive Barriers for Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal and Radioactive Citation Details In-Document Search Title: Long-term Stewardship of Mixed Wastes: Passive Reactive Barriers for Simultaneous In Situ Remediation of Chlorinated Solvent, Heavy Metal and Radioactive This project report

  1. Double Shock Experiments and Reactive Flow Modeling of High Pressure LX-17

    Office of Scientific and Technical Information (OSTI)

    Detonation Reaction Product States (Conference) | SciTech Connect Double Shock Experiments and Reactive Flow Modeling of High Pressure LX-17 Detonation Reaction Product States Citation Details In-Document Search Title: Double Shock Experiments and Reactive Flow Modeling of High Pressure LX-17 Detonation Reaction Product States Authors: Vandersall, K S ; Garcia, F ; Fried, L E ; Tarver, C M Publication Date: 2014-06-24 OSTI Identifier: 1169870 Report Number(s): LLNL-CONF-656252

  2. Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact

    Office of Scientific and Technical Information (OSTI)

    on Geomechanical Properties of Reservoir Rocks and Seals (Journal Article) | SciTech Connect Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals Citation Details In-Document Search Title: Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals This article develops a novel multiscale modeling approach to analyze CO2 reservoirs using

  3. Reactive Dehydration technology for Production of Fuels and Chemicals from Biomass

    Energy Savers [EERE]

    Dr. James R. Kittrell, KSE, Inc. Dr. Carl R. Dupre, KSE, Inc. Dr. Michael F. Malone (Subcontractor) U.S. DOE Advanced Manufacturing Office Peer Review Meeting Washington, D.C. May 6-7, 2014 This presentation does not contain any proprietary, confidential, or otherwise restricted information. 2 Project Objective Commercialize a novel reactive distillation technology using the iCARD platform (Intensified Catalytic and Reactive Distillation) for compact, inexpensive production of biomass-based

  4. COS OBSERVATIONS OF METAL LINE AND BROAD LYMAN-{alpha} ABSORPTION IN THE MULTI-PHASE O VI AND Ne VIII SYSTEM AT z = 0.20701 TOWARD HE 0226-4110

    SciTech Connect (OSTI)

    Savage, B. D. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Lehner, N. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Narayanan, A. [Indian Institute of Space Science and Technology, Thiruvananthapuram 695547, Kerala (India)

    2011-12-20

    Observations of the QSO HE 0226-4110 (z{sub em} = 0.495) with the Cosmic Origins Spectrograph (COS) from 1134 to 1796 A with a resolution of {approx}17 km s{sup -1} and signal-to-noise ratio (S/N) per resolution element of 20-40 are used to study the multi-phase absorption system at z = 0.20701 containing O VI and Ne VIII. The system was previously studied with lower S/N observations with Far-Ultraviolet Spectroscopic Explorer (FUSE) and Space Telescope Imaging Spectrograph (STIS). The COS observations provide more reliable measures of the H I and metal lines present in the system and reveal the clear presence of broad Ly{alpha} (BLA) absorption with b = 72(+13, -6) km s{sup -1} and log N(H I) = 13.87 {+-} 0.08. Detecting BLAs associated with warm gas absorbers is crucial for determining the temperature, metallicity, and total baryonic content of the absorbers. The BLA is probably recording the trace amount of thermally broadened H I in the collisionally ionized plasma with log T {approx} 5.7 that also produces the O VI and Ne VIII absorption. The total hydrogen column in the collisionally ionized gas, log N(H) {approx} 20.1, exceeds that in the cooler photoionized gas in the system by a factor of {approx}22. The oxygen abundance in the collisionally ionized gas is [O/H] = -0.89 {+-} 0.08 {+-} 0.07. The absorber probably occurs in the circumgalactic environment (halo) of a foreground L = 0.25L{sub *} disk galaxy with an impact parameter of 109 h{sub 70}{sup -1} kpc identified by Mulchaey and Chen.

  5. Application of a data assimilation method via an ensemble Kalman filter to reactive urea hydrolysis transport modeling

    SciTech Connect (OSTI)

    Juxiu Tong; Bill X. Hu; Hai Huang; Luanjin Guo; Jinzhong Yang

    2014-03-01

    With growing importance of water resources in the world, remediations of anthropogenic contaminations due to reactive solute transport become even more important. A good understanding of reactive rate parameters such as kinetic parameters is the key to accurately predicting reactive solute transport processes and designing corresponding remediation schemes. For modeling reactive solute transport, it is very difficult to estimate chemical reaction rate parameters due to complex processes of chemical reactions and limited available data. To find a method to get the reactive rate parameters for the reactive urea hydrolysis transport modeling and obtain more accurate prediction for the chemical concentrations, we developed a data assimilation method based on an ensemble Kalman filter (EnKF) method to calibrate reactive rate parameters for modeling urea hydrolysis transport in a synthetic one-dimensional column at laboratory scale and to update modeling prediction. We applied a constrained EnKF method to pose constraints to the updated reactive rate parameters and the predicted solute concentrations based on their physical meanings after the data assimilation calibration. From the study results we concluded that we could efficiently improve the chemical reactive rate parameters with the data assimilation method via the EnKF, and at the same time we could improve solute concentration prediction. The more data we assimilated, the more accurate the reactive rate parameters and concentration prediction. The filter divergence problem was also solved in this study.

  6. Rudimentary, low tech incinerators as a means to produce reactive pozzolan out of sugar cane straw

    SciTech Connect (OSTI)

    Martirena, Fernando . E-mail: f.martirena@enet.cu; Middendorf, Bernhard; Day, Robert L.; Gehrke, Matthias; Roque, Pablo; Martinez, Lesday; Betancourt, Sergio

    2006-06-15

    The ashes of agricultural wastes from the processing of sugar cane are recognized as having pozzolanic properties. Burning of these wastes under controlled conditions, e.g. temperature and residence time results in significant improvement in reactivity. There are many reports of low-tech incinerators that have been successfully used to produce reactive rice husk ash in Asia. The paper presents the results of the evaluation of a rudimentary incinerator where sugar cane straw is burnt in order to obtain a reactive ash. The incinerator is designed and constructed according to state-of-the-art recommendations for this kind of device. Various burning trials were performed in order to obtain ash for the experiment. X-ray diffraction analysis performed on powdered ash shows significant presence of amorphous (glassy) material. Lime-pozzolana pastes were prepared. The pastes were subjected to X-ray diffraction, thermo-gravimetric analysis, chemical titration, and SEM observation, as a means to examine the pozzolanicity of the ash via the progress with time of calcium hydroxide consumption, and changes in the pore size distribution and strength. Calcium silicate hydrate phases are the main reaction product of the pozzolanic reaction. The long residence time of the ash in the burning chamber seems to be the reason for the fairly low reactivity of the ash; the reactivity of the ash was not significantly improved in comparison with that of the ash burnt in uncontrolled conditions in the open air.

  7. Reactive power interconnection requirements for PV and wind plants : recommendations to NERC.

    SciTech Connect (OSTI)

    McDowell, Jason; Walling, Reigh; Peter, William; Von Engeln, Edi; Seymour, Eric; Nelson, Robert; Casey, Leo; Ellis, Abraham; Barker, Chris.

    2012-02-01

    Voltage on the North American bulk system is normally regulated by synchronous generators, which typically are provided with voltage schedules by transmission system operators. In the past, variable generation plants were considered very small relative to conventional generating units, and were characteristically either induction generator (wind) or line-commutated inverters (photovoltaic) that have no inherent voltage regulation capability. However, the growing level of penetration of non-traditional renewable generation - especially wind and solar - has led to the need for renewable generation to contribute more significantly to power system voltage control and reactive power capacity. Modern wind-turbine generators, and increasingly PV inverters as well, have considerable dynamic reactive power capability, which can be further enhanced with other reactive support equipment at the plant level to meet interconnection requirements. This report contains a set of recommendations to the North-America Electricity Reliability Corporation (NERC) as part of Task 1-3 (interconnection requirements) of the Integration of Variable Generation Task Force (IVGTF) work plan. The report discusses reactive capability of different generator technologies, reviews existing reactive power standards, and provides specific recommendations to improve existing interconnection standards.

  8. A Preliminary Analysis of the Economics of Using Distributed Energy as a Source of Reactive Power Supply

    SciTech Connect (OSTI)

    Li, Fangxing; Kueck, John D; Rizy, D Tom; King, Thomas F

    2006-04-01

    A major blackout affecting 50 million people in the Northeast United States, where insufficient reactive power supply was an issue, and an increased number of filings made to the Federal Energy Regulatory Commission by generators for reactive power has led to a closer look at reactive power supply and compensation. The Northeastern Massachusetts region is one such area where there is an insufficiency in reactive power compensation. Distributed energy due to its close proximity to loads seems to be a viable option for solving any present or future reactive power shortage problems. Industry experts believe that supplying reactive power from synchronized distributed energy sources can be 2 to 3 times more effective than providing reactive support in bulk from longer distances at the transmission or generation level. Several technology options are available to supply reactive power from distributed energy sources such as small generators, synchronous condensers, fuel cells or microturbines. In addition, simple payback analysis indicates that investments in DG to provide reactive power can be recouped in less than 5 years when capacity payments for providing reactive power are larger than $5,000/kVAR and the DG capital and installation costs are lower than $30/kVAR. However, the current institutional arrangements for reactive power compensation present a significant barrier to wider adoption of distributed energy as a source of reactive power. Furthermore, there is a significant difference between how generators and transmission owners/providers are compensated for reactive power supplied. The situation for distributed energy sources is even more difficult, as there are no arrangements to compensate independent DE owners interested in supplying reactive power to the grid other than those for very large IPPs. There are comparable functionality barriers as well, as these smaller devices do not have the control and communications requirements necessary for automatic operation in response to local or system operators. There are no known distributed energy asset owners currently receiving compensation for reactive power supply or capability. However, there are some cases where small generators on the generation and transmission side of electricity supply have been tested and have installed the capability to be dispatched for reactive power support. Several concerns need to be met for distributed energy to become widely integrated as a reactive power resource. The overall costs of retrofitting distributed energy devices to absorb or produce reactive power need to be reduced. There needs to be a mechanism in place for ISOs/RTOs to procure reactive power from the customer side of the meter where distributed energy resides. Novel compensation methods should be introduced to encourage the dispatch of dynamic resources close to areas with critical voltage issues. The next phase of this research will investigate in detail how different options of reactive power producing DE can compare both economically and functionally with shunt capacitor banks. Shunt capacitor banks, which are typically used for compensating reactive power consumption of loads on distribution systems, are very commonly used because they are very cost effective in terms of capital costs. However, capacitor banks can require extensive maintenance especially due to their exposure to lightning at the top of utility poles. Also, it can be problematic to find failed capacitor banks and their maintenance can be expensive, requiring crews and bucket trucks which often requires total replacement. Another shortcoming of capacitor banks is the fact that they usually have one size at a location (typically sized as 300, 600, 900 or 1200kVAr) and thus don't have variable range as do reactive power producing DE, and cannot respond to dynamic reactive power needs. Additional future work is to find a detailed methodology to identify the hidden benefit of DE for providing reactive power and the best way to allocate the benefit among customers, utilities, transmission companies or RTOs.

  9. Methods and apparatuses for reagent delivery, reactive barrier formation, and pest control

    DOE Patents [OSTI]

    Gilmore, Tyler [Pasco, WA; Kaplan, Daniel I [Aiken, SC; Last, George [Richland, WA

    2002-07-09

    A reagent delivery method includes positioning reagent delivery tubes in contact with soil. The tubes can include a wall that is permeable to a soil-modifying reagent. The method further includes supplying the reagent in the tubes, diffusing the reagent through the permeable wall and into the soil, and chemically modifying a selected component of the soil using the reagent. The tubes can be in subsurface contact with soil, including groundwater, and can be placed with directional drilling equipment independent of groundwater well casings. The soil-modifying reagent includes a variety of gases, liquids, colloids, and adsorbents that may be reactive or non-reactive with soil components. The method may be used inter alia to form reactive barriers, control pests, and enhance soil nutrients for microbes and plants.

  10. Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound

    SciTech Connect (OSTI)

    Gardner, Todd H.; Gasper-Galvin, Lee D.

    1996-12-01

    Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.

  11. Pore scale modeling of reactive transport involved in geologic CO2 sequestration

    SciTech Connect (OSTI)

    Kang, Qinjin; Lichtner, Peter C; Viswanathan, Hari S; Abdel-fattah, Amr I

    2009-01-01

    We apply a multi-component reactive transport lattice Boltzmann model developed in previolls studies to modeling the injection of a C02 saturated brine into various porous media structures at temperature T=25 and 80 C. The porous media are originally consisted of calcite. A chemical system consisting of Na+, Ca2+, Mg2+, H+, CO2(aq), and CI-is considered. The fluid flow, advection and diHusion of aqueous species, homogeneous reactions occurring in the bulk fluid, as weB as the dissolution of calcite and precipitation of dolomite are simulated at the pore scale. The effects of porous media structure on reactive transport are investigated. The results are compared with continuum scale modeling and the agreement and discrepancy are discussed. This work may shed some light on the fundamental physics occurring at the pore scale for reactive transport involved in geologic C02 sequestration.

  12. Chemical reactivity of CVC and CVD SiC with UO2 at high temperatures

    SciTech Connect (OSTI)

    Silva, Chinthaka M; Katoh, Yutai; Voit, Stewart L; Snead, Lance Lewis

    2015-01-01

    Two types of silicon carbide (SiC) synthesized using two different vapor deposition processes were embedded in UO2 pellets and evaluated for their potential chemical reaction with UO2. While minor reactivity between chemical-vapor-composited (CVC) SiC and UO2 was observed at comparatively low temperatures of 1100 and 1300 C, chemical-vapor-deposited (CVD) SiC did not show any such reactivity, according to microstructural investigations. However, both CVD and CVC SiCs showed some reaction with UO2 at a higher temperature (1500 C). Elemental maps supported by phase maps obtained using electron backscatter diffraction indicated that CVC SiC was more reactive than CVD SiC at 1500 C. Furthermore, this investigation indicated the formation of uranium carbides and uranium silicide chemical phases such as UC, USi2, and U3Si2 as a result of SiC reaction with UO2.

  13. Impact of California Phase 2 reformulated gasoline on atmospheric reactivity of exhaust and evaporative emissions

    SciTech Connect (OSTI)

    Kirchstetter, T.W.; Singer, B.C.; Harley, R.A.; Kendall, G.R.; Traverse, M.

    1997-12-31

    Phase 2 of California`s reformulated gasoline (RFG) program took effect statewide in the first half of 1996. Changes to gasoline composition required by Phase 2 specifications included: lower vapor pressure; lower olefin, aromatic, benzene, and sulfur content; lower T50 and T90; and a minimum oxygen content. In this paper, impacts of Phase 2 RFG on the atmospheric reactivity of motor vehicle exhaust and evaporative emissions are described. Volatile organic compounds in motor vehicle exhaust were measured at the Caldecott tunnel in summer 1995 and 1996. Aggregate emissions of greater than 8000 vehicles were measured each day. Regular and premium grade gasoline samples were collected from service stations in Berkeley concurrently with tunnel measurements both summers. Liquid gasoline samples and their headspace vapors were analyzed to determine detailed chemical composition. Normalized reactivity was calculated for exhaust and evaporative emissions by applying maximum incremental reactivity values to the detailed speciation profiles. Results indicate that the composition of gasoline in 1996 differed markedly from that of 1995. Changes in liquid gasoline composition led to corresponding changes in the speciation of vehicle exhaust and of gasoline headspace vapors. Benzene concentration in liquid gasoline decreased from 2.0 to 0.6 wt%, which contributed to a 70 and 37% reduction in benzene weight fraction in headspace vapors and vehicle exhaust, respectively. Addition of MTBE and reduction of olefins and aromatics in gasoline led to significant reductions in the atmospheric reactivity of unburned gasoline and gasoline headspace vapors. The normalized reactivity of liquid gasoline and headspace vapors decreased by 23 and 19%, respectively, between 1995 and 1996. The normalized reactivity of non-methane organic compounds in vehicle exhaust decreased by about 8%, but the uncertainty in this change was large.

  14. Advancing reactive tracer methods for measuring thermal evolution in CO2-and water-based geothermal reservoirs

    Broader source: Energy.gov [DOE]

    DOE Geothermal Peer Review 2010 - Presentation. This project aims to develop reactive tracer method for monitoring thermal drawdown in enhanced geothermal systems.

  15. WSi2/Si Multilayer Sectioning by Reactive Ion Etching for Multilayer Laue Lens Fabrication

    SciTech Connect (OSTI)

    Bouet, N.; Conley, R.; Biancarosaa, J.; Divanc, R.; Macrander, A. T.

    2010-08-01

    SPIE Conference paper/talk presentation: Introduction: Reactive ion etching (RIE) has been employed in a wide range of fields such as semiconductor fabrication, MEMS (microelectromechanical systems), and refractive x-ray optics with a large investment put towards the development of deep RIE. Due to the intrinsic differing chemistries related to reactivity, ion bombardment, and passivation of materials, the development of recipes for new materials or material systems can require intense effort and resources. For silicon in particular, methods have been developed to provide reliable anisotropic profiles with good dimensional control and high aspect ratios1,2,3, high etch rates, and excellent material to mask etch selectivity...

  16. Nanopore reactive adsorbents for the high-efficiency removal of waste species

    DOE Patents [OSTI]

    Yang, Arthur Jing-Min; Zhang, Yuehua

    2005-01-04

    A nanoporous reactive adsorbent incorporates a relatively small number of relatively larger reactant, e.g., metal, enzyme, etc., particles (10) forming a discontinuous or continuous phase interspersed among and surrounded by a continuous phase of smaller adsorbent particles (12) and connected interstitial pores (14) therebetween. The reactive adsorbent can effectively remove inorganic or organic impurities in a liquid by causing the liquid to flow through the adsorbent. For example, silver ions may be adsorbed by the adsorbent particles (12) and reduced to metallic silver by reducing metal, such as ions, as the reactant particles (10). The column can be regenerated by backwashing with the liquid effluent containing, for example, acetic acid.

  17. Sub-picosecond IR study of the reactive intermediate in an alkane C-H bond

    Office of Scientific and Technical Information (OSTI)

    activation reaction by CpRh(CO)2 (Journal Article) | SciTech Connect Journal Article: Sub-picosecond IR study of the reactive intermediate in an alkane C-H bond activation reaction by CpRh(CO)2 Citation Details In-Document Search Title: Sub-picosecond IR study of the reactive intermediate in an alkane C-H bond activation reaction by CpRh(CO)2 No abstract prepared. Authors: Asbury, John B. ; Ghosh, Hirendra N. ; Yeston, Jake S. ; Bergman, Robert G. ; Lian, Tianquan Publication Date:

  18. reactive ion solvation and solid-liquid interfacial reactions in aqueous

    Office of Scientific and Technical Information (OSTI)

    and non-aqueous media. (Conference) | SciTech Connect reactive ion solvation and solid-liquid interfacial reactions in aqueous and non-aqueous media. Citation Details In-Document Search Title: reactive ion solvation and solid-liquid interfacial reactions in aqueous and non-aqueous media. Abstract not provided. Authors: Leung, Kevin Publication Date: 2012-07-01 OSTI Identifier: 1116815 Report Number(s): SAND2012-5477C 480644 DOE Contract Number: AC04-94AL85000 Resource Type: Conference

  19. Multiphase Flow with Interphase eXchanges

    Energy Science and Technology Software Center (OSTI)

    1995-03-01

    MFIX is a general-purpose hydrodynamic model that describes chemical reactions and heat transfer in dense or dilute fluid-solids flows, flows typically occurring in energy conversion and chemical processing reactors. With such information, the engineer can visualize the conditions in the reactor, conduct parametric studies and what-if experiments, and, thereby, assist in the design process. MFIX has the following modeling capabilities: mass and momentum balance equations for gas and multiple solids phases; a gas phase andmore » two solids phase energy equation; an arbitrary number of species balance equations for each of the phases; granular stress equations based on kinetic theory and frictional flow theory; a user-defined chemistry subroutine; three-dimensional Cartesin or cylindrical coordinate systems; nonuniform mesh size; impermeable and semi-permeable internal surfaces; user-friendly input data file; multiple, single-precision, binary direct-access output files that minimize disk storage and accelerate data retrieval; extensive error reporting; post-processors for creating animations and for extracting and manipulating output data.« less

  20. Control rod calibration and reactivity effects at the IPEN/MB-01 reactor

    SciTech Connect (OSTI)

    Pinto, Letícia Negrão; Gonnelli, Eduardo; Santos, Adimir dos

    2014-11-11

    Researches that aim to improve the performance of neutron transport codes and quality of nuclear cross section databases are very important to increase the accuracy of simulations and the quality of the analysis and prediction of phenomena in the nuclear field. In this context, relevant experimental data such as reactivity worth measurements are needed. Control rods may be made of several neutron absorbing materials that are used to adjust the reactivity of the core. For the reactor operation, these experimental data are also extremely important: with them it is possible to estimate the reactivity worth by the movement of the control rod, understand the reactor response at each rod position and to operate the reactor safely. This work presents a temperature correction approach for the control rod calibration problem. It is shown the control rod calibration data of the IPEN/MB-01 reactor, the integral and differential reactivity curves and a theoretical analysis, performed by the MCNP-5 reactor physics code, developed and maintained by Los Alamos National Laboratory, using the ENDF/B-VII.0 nuclear data library.

  1. Reactive barrier technologies for treatment of contaminated groundwater at Rocky Flats

    SciTech Connect (OSTI)

    Marozas, D.C.; Bujewski, G.E.; Castaneda, N.

    1997-12-31

    The U.S. Department of Energy (DOE) Office of Science and Technology Subsurface Contaminants Focus Area is supporting the investigation of reactive barrier technologies to mitigate the risks associated with mixed organic/radioactive waste at several DOE sites. Groundwater from a small contaminated plume at the Rocky Flats Environmental Technology Site (RFETS) is being used to evaluate passive reactive material treatment. Permeable reactive barriers which intercept contaminants and destroy the VOC component while containing radionuclides are attractive for a number of reasons relating to public and regulatory acceptance. In situ treatment keeps contaminants away from the earth`s surface, there is no above-ground treatment equipment that could expose workers and the public and operational costs are expected to be lower than currently used technologies. This paper will present results from preliminary site characterization and in-field small-scale column testing of reactive materials at RFETS. Successful demonstration is expected to lead to full-scale implementation of the technology at several DOE sites, including Rocky Flats.

  2. Uranium transport in a crushed granodiorite: Experiments and reactive transport modeling

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

    Dittrich, T. M.; Reimus, P. W.

    2015-02-12

    The primary objective of this study was to develop and demonstrate an experimental method to refine and better parameterize process models for reactive contaminant transport in aqueous subsurface environments and to reduce conservatism in such models without attempting to fully describe the geochemical system.

  3. Reactivity Controlled Compression Ignition (RCCI) Combustion on a Multi-Cylinder Light-Duty Diesel Engine

    SciTech Connect (OSTI)

    Curran, Scott; Hanson, Reed M; Wagner, Robert M

    2012-01-01

    Reactivity controlled compression ignition is a low-temperature combustion technique that has been shown, both in computational fluid dynamics modeling and single-cylinder experiments, to obtain diesel-like efficiency or better with ultra-low nitrogen oxide and soot emissions, while operating primarily on gasoline-like fuels. This paper investigates reactivity controlled compression ignition operation on a four-cylinder light-duty diesel engine with production-viable hardware using conventional gasoline and diesel fuel. Experimental results are presented over a wide speed and load range using a systematic approach for achieving successful steady-state reactivity controlled compression ignition combustion. The results demonstrated diesel-like efficiency or better over the operating range explored with low engine-out nitrogen oxide and soot emissions. A peak brake thermal efficiency of 39.0% was demonstrated for 2600 r/min and 6.9 bar brake mean effective pressure with nitrogen oxide emissions reduced by an order of magnitude compared to conventional diesel combustion operation. Reactivity controlled compression ignition emissions and efficiency results are compared to conventional diesel combustion operation on the same engine.

  4. ADVANCING REACTIVE TRACER METHODS FOR MONITORING THERMAL DRAWDOWN IN GEOTHERMAL ENHANCED GEOTHERMAL RESERVOIRS

    SciTech Connect (OSTI)

    Mitchell A. Plummer; Carl D. Palmer; Earl D. Mattson; George D. Redden; Laurence C. Hull

    2010-10-01

    Reactive tracers have long been considered a possible means of measuring thermal drawdown in a geothermal system, before significant cooling occurs at the extraction well. Here, we examine the sensitivity of the proposed method to evaluate reservoir cooling and demonstrate that while the sensitivity of the method as generally proposed is low, it may be practical under certain conditions.

  5. EV/PHEV Bidirectional Charger Assessment for V2G Reactive Power Operation

    SciTech Connect (OSTI)

    Kisacikoglu, Mithat C; Ozpineci, Burak; Tolbert, Leon M

    2013-01-01

    This paper presents a summary of the available single-phase ac-dc topologies used for EV/PHEV, level-1 and -2 on-board charging and for providing reactive power support to the utility grid. It presents the design motives of single-phase on-board chargers in detail and makes a classification of the chargers based on their future vehicle-to-grid usage. The pros and cons of each different ac-dc topology are discussed to shed light on their suitability for reactive power support. This paper also presents and analyzes the differences between charging-only operation and capacitive reactive power operation that results in increased demand from the dc-link capacitor (more charge/discharge cycles and increased second harmonic ripple current). Moreover, battery state of charge is spared from losses during reactive power operation, but converter output power must be limited below its rated power rating to have the same stress on the dc-link capacitor.

  6. STOMP-ECKEChem: An Engineering Perspective on Reactive Transport in Geologic Media

    SciTech Connect (OSTI)

    White, Mark D.; Fang, Yilin

    2012-04-04

    ECKEChem (Equilibrium, Conservation, Kinetic Equation Chemistry) is a reactive transport module for the STOMP suite of multifluid subsurface flow and transport simulators that was developed from an engineering perspective. STOMP comprises a suite of operational modes that are distinguished by the solved coupled conservation equations with capabilities for a variety of subsurface applications (e.g., environmental remediation and stewardship, geologic sequestration of greenhouse gases, gas hydrate production, and oil shale production). The ECKEChem module was designed to provide integrated reactive transport capabilities across the suite of STOMP simulator operational modes. The initial application for the ECKEChem module was in the simulation of the mineralization reactions that occurred with the injection of supercritical carbon dioxide into deep Columbia River basalt formations, where it was implemented in the STOMP-CO2 simulator. The STOMP-ECKEChem solution approach to modeling reactive transport in multifluid geologic media is founded on an engineering perspective: (1) sequential non-iterative coupling between the flow and reactive transport is sufficient, (2) reactive transport can be modeled by operator splitting with local geochemistry and global transport, (3) geochemistry can be expressed as a system of coupled nonlinear equilibrium, conservation and kinetic equations, (4) a limited number of kinetic equation forms are used in geochemical practice. This chapter describes the conceptual approach to converting a geochemical reaction network into a series of equilibrium, conservation and kinetic equations, the implementation of ECKEChem in STOMP, the numerical solution approach, and a demonstration of the simulator on a complex application involving desorption of uranium from contaminated field-textured sediments.

  7. Evaluation of a permeable reactive barrier technology for use at Rocky Flats Environmental Technology Site (RFETS)

    SciTech Connect (OSTI)

    DWYER,BRIAN P.

    2000-01-01

    Three reactive materials were evaluated at laboratory scale to identify the optimum treatment reagent for use in a Permeable Reactive Barrier Treatment System at Rocky Flats Environmental Technology Site (RFETS). The contaminants of concern (COCS) are uranium, TCE, PCE, carbon tetrachloride, americium, and vinyl chloride. The three reactive media evaluated included high carbon steel iron filings, an iron-silica alloy in the form of a foam aggregate, and a peculiar humic acid based sorbent (Humasorb from Arctech) mixed with sand. Each material was tested in the laboratory at column scale using simulated site water. All three materials showed promise for the 903 Mound Site however, the iron filings were determined to be the least expensive media. In order to validate the laboratory results, the iron filings were further tested at a pilot scale (field columns) using actual site water. Pilot test results were similar to laboratory results; consequently, the iron filings were chosen for the fill-scale demonstration of the reactive barrier technology. Additional design parameters including saturated hydraulic conductivity, treatment residence time, and head loss across the media were also determined and provided to the design team in support of the final design. The final design was completed by the Corps of Engineers in 1997 and the system was constructed in the summer of 1998. The treatment system began fill operation in December, 1998 and despite a few problems has been operational since. Results to date are consistent with the lab and pilot scale findings, i.e., complete removal of the contaminants of concern (COCs) prior to discharge to meet RFETS cleanup requirements. Furthermore, it is fair to say at this point in time that laboratory developed design parameters for the reactive barrier technology are sufficient for fuel scale design; however,the treatment system longevity and the long-term fate of the contaminants are questions that remain unanswered. This project along with others such as the Durango, CO and Monticello, UT reactive barriers will provide the data to determine the long-term effectiveness and return on investment (ROI) for this technology for comparison to the baseline pump and treat.

  8. Overview on backfill materials and permeable reactive barriers for nuclear waste disposal facilities.

    SciTech Connect (OSTI)

    Moore, Robert Charles; Hasan, Ahmed Ali Mohamed; Holt, Kathleen Caroline; Hasan, Mahmoud A.

    2003-10-01

    A great deal of money and effort has been spent on environmental restoration during the past several decades. Significant progress has been made on improving air quality, cleaning up and preventing leaching from dumps and landfills, and improving surface water quality. However, significant challenges still exist in all of these areas. Among the more difficult and expensive environmental problems, and often the primary factor limiting closure of contaminated sites following surface restoration, is contamination of ground water. The most common technology used for remediating ground water is surface treatment where the water is pumped to the surface, treated and pumped back into the ground or released at a nearby river or lake. Although still useful for certain remediation scenarios, the limitations of pump-and-treat technologies have recently been recognized, along with the need for innovative solutions to ground-water contamination. Even with the current challenges we face there is a strong need to create geological repository systems for dispose of radioactive wastes containing long-lived radionuclides. The potential contamination of groundwater is a major factor in selection of a radioactive waste disposal site, design of the facility, future scenarios such as human intrusion into the repository and possible need for retrieving the radioactive material, and the use of backfills designed to keep the radionuclides immobile. One of the most promising technologies for remediation of contaminated sites and design of radioactive waste repositories is the use of permeable reactive barriers (PRBs). PRBs are constructed of reactive material(s) to intercept and remove the radionuclides from the water and decontaminate the plumes in situ. The concept of PRBs is relatively simple. The reactive material(s) is placed in the subsurface between the waste or contaminated area and the groundwater. Reactive materials used thus far in practice and research include zero valent iron, hydroxyapatite, magnesium oxide, and others. As the contaminant moves through the reactive material, the contaminant is either sorbed by the reactive material or chemically reacts with the material to form a less harmful substance. Because of the high risk associated with failure of a geological repository for nuclear waste, most nations favor a near-field multibarrier engineered system using backfill materials to prevent release of radionuclides into the surrounding groundwater.

  9. Apparatus and method for atmospheric pressure reactive atom plasma processing for shaping of damage free surfaces

    DOE Patents [OSTI]

    Carr; Jeffrey W. (Livermore, CA)

    2009-03-31

    Fabrication apparatus and methods are disclosed for shaping and finishing difficult materials with no subsurface damage. The apparatus and methods use an atmospheric pressure mixed gas plasma discharge as a sub-aperture polisher of, for example, fused silica and single crystal silicon, silicon carbide and other materials. In one example, workpiece material is removed at the atomic level through reaction with fluorine atoms. In this example, these reactive species are produced by a noble gas plasma from trace constituent fluorocarbons or other fluorine containing gases added to the host argon matrix. The products of the reaction are gas phase compounds that flow from the surface of the workpiece, exposing fresh material to the etchant without condensation and redeposition on the newly created surface. The discharge provides a stable and predictable distribution of reactive species permitting the generation of a predetermined surface by translating the plasma across the workpiece along a calculated path.

  10. Catalytic and reactive polypeptides and methods for their preparation and use

    DOE Patents [OSTI]

    Schultz, Peter (Oakland, CA)

    1994-01-01

    Catalytic and reactive polypeptides include a binding site specific for a reactant or reactive intermediate involved in a chemical reaction of interest. The polypeptides further include at least one active functionality proximate the binding site, where the active functionality is capable of catalyzing or chemically participating in the chemical reaction in such a way that the reaction rate is enhanced. Methods for preparing the catalytic peptides include chemical synthesis, site-directed mutagenesis of antibody and enzyme genes, covalent attachment of the functionalities through particular amino acid side chains, and the like. This invention was made with Government support under Grant Contract No. AI-24695, awarded by the Department of health and Human Services, and under Grant Contract No. N 00014-87-K-0256, awarded by the Office of Naval Research. The Government has certain rights in this invention.

  11. DIESEL OXIDATION CATALYST CONTROL OF HYDROCARBON AEROSOLS FROM REACTIVITY CONTROLLED COMPRESSION IGNITION COMBUSTION

    SciTech Connect (OSTI)

    Prikhodko, Vitaly Y; Parks, II, James E; Barone, Teresa L; Curran, Scott; Cho, Kukwon; Lewis Sr, Samuel Arthur; Storey, John Morse; Wagner, Robert M

    2011-01-01

    Reactivity Controlled Compression Ignition (RCCI) is a novel combustion process that utilizes two fuels with different reactivity to stage and control combustion and enable homogeneous combustion. The technique has been proven experimentally in previous work with diesel and gasoline fuels; low NOx emissions and high efficiencies were observed from RCCI in comparison to conventional combustion. In previous studies on a multi-cylinder engine, particulate matter (PM) emission measurements from RCCI suggested that hydrocarbons were a major component of the PM mass. Further studies were conducted on this multi-cylinder engine platform to characterize the PM emissions in more detail and understand the effect of a diesel oxidation catalyst (DOC) on the hydrocarbon-dominated PM emissions. Results from the study show that the DOC can effectively reduce the hydrocarbon emissions as well as the overall PM from RCCI combustion. The bimodal size distribution of PM from RCCI is altered by the DOC which reduces the smaller mode 10 nm size particles.

  12. Plasma chemistry fluctuations in a reactive arc plasma in the presence of magnetic fields

    SciTech Connect (OSTI)

    Rosen, J.; Anders, A.; Schneider, J.M.

    2002-01-13

    The effect of a magnetic field on the plasma chemistry and pulse-to-pulse fluctuations of cathodic arc ion charge state distributions in a reactive environment were investigated. The plasma composition was measured by time-of-flight charge-to-mass spectrometry. The fluctuation of the concentrations of Al+, Al2+ and Al3+ was found to increase with an increasing magnetic field strength. We suggest that this is caused by magnetic field dependent fluctuations of the energy input into cathode spots as seen through fluctuations of the cathode potential. These results are qualitatively consistent with the model of partial local Saha equilibrium and are of fundamental importance for the evolution of the structure of films deposited by reactive cathodic arc deposition.

  13. Method of extruding and packaging a thin sample of reactive material including forming the extrusion die

    DOE Patents [OSTI]

    Lewandowski, Edward F. (Westmont, IL); Peterson, Leroy L. (Joliet, IL)

    1985-01-01

    This invention teaches a method of cutting a narrow slot in an extrusion die with an electrical discharge machine by first drilling spaced holes at the ends of where the slot will be, whereby the oil can flow through the holes and slot to flush the material eroded away as the slot is being cut. The invention further teaches a method of extruding a very thin ribbon of solid highly reactive material such as lithium or sodium through the die in an inert atmosphere of nitrogen, argon or the like as in a glovebox. The invention further teaches a method of stamping out sample discs from the ribbon and of packaging each disc by sandwiching it between two aluminum sheets and cold welding the sheets together along an annular seam beyond the outer periphery of the disc. This provides a sample of high purity reactive material that can have a long shelf life.

  14. Method of extruding and packaging a thin sample of reactive material, including forming the extrusion die

    DOE Patents [OSTI]

    Lewandowski, E.F.; Peterson, L.L.

    1981-11-30

    This invention teaches a method of cutting a narrow slot in an extrusion die with an electrical discharge machine by first drilling spaced holes at the ends of where the slot will be, whereby the oil can flow through the holes and slot to flush the material eroded away as the slot is being cut. The invention further teaches a method of extruding a very thin ribbon of solid highly reactive material such as lithium or sodium through the die in an inert atmosphere of nitrogen, argon, or the like as in a glovebox. The invention further teaches a method of stamping out sample discs from the ribbon and of packaging each disc by sandwiching it between two aluminum sheets and cold welding the sheets together along an annular seam beyond the outer periphery of the disc. This provides a sample of high purity reactive material that can have a long shelf life.

  15. Hydrogen absorption characteristics of amorphous LaNi[sub 5. 0] films prepared by reactive sputtering

    SciTech Connect (OSTI)

    Sakaguchi, H.; Tsujimoto, T.; Adachi, Ginya (Osaka University, Suita (Japan))

    1993-01-01

    Amorphous LaNi[sub 5] thin films are expected to be one of the promising materials for use in hydrogen separation and battery electrodes, because the durability of the films is great in regard to the hydrogen absorption-desorption cycling process and the films have excellent resistance to harmful impurities in the hydrogen gas in comparison with the crystalline bulk material. An amorphous LaNi[sub 5.0] film having high hydrogen density and low hydrogen-induced stress was obtained by means of a reactive sputtering method using an Ar-H[sub 2] gas mixture. Pressure-composition isotherms show that the amount of hydrogen (H/LaNi[sub 5.0]) taken up by a formula weight of LaNi[sub 5.0] is about 1.5 times larger for the reactive sputtered film than for the conventional sputtered film prepared by using Ar gas. 18 refs., 1 fig, 1 tabs.

  16. Enabling Clean Consumption of Low Btu and Reactive Fuels in Gas Turbines

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

    Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels ADVANCED MANUFACTURING OFFICE Enabling Clean Combustion of Low-Btu and Reactive Fuels in Gas Turbines By enabling ultralow-emission, lean premixed combustion of a wide range of gaseous opportunity fuels, this unique, fuel- fexible catalytic combustor for gas turbines can reduce natural gas consumption in industry. Introduction Gas turbines are commonly used in industry for onsite power and heating needs because of their high

  17. Microsoft PowerPoint - Tritium Gas Stream Scrubbing using In-situ Reactive Materials.pptx

    Office of Environmental Management (EM)

    Stream Scrubbing using In-situ Reactive Materials Paul Korinko, Simona Murph, and George Larsen Tritium Focus Group Meeting LANL Nov 3-5, 2015 SRNL-STI-2015-00597 Tritium Production and Extraction * Tritium Producing Burnable Absorber Rods (TPBARs) * Built to strict materials specifications * Coatings, ceramics, metals, processes * Meet NQA-1 requirements * Irradiated in a commercial light water reactor * Extracted at SRS in the Tritium Extraction Facility * Waste disposed on-site Contamination

  18. Interactions between ingredients in IMX-101: Reactive Chemical Processes Control Insensitive Munitions Properties

    SciTech Connect (OSTI)

    Maharrey, Sean P.; Wiese-Smith, Deneille; Highley, Aaron M.; Behrens, Richard; Kay, Jeffrey J

    2014-03-01

    Simultaneous Thermogravimetric Modulated Beam Mass Spectrometry (STMBMS) measurements have been conducted on a new Insensitive Munitions (IM) formulation. IMX-101 is the first explosive to be fully IM qualified under new NATO STANAG guidelines for fielded munitions. The formulation uses dinitroanisole (DNAN) as a new melt cast material to replace TNT, and shows excellent IM performance when formulated with other energetic ingredients. The scope of this work is to explain this superior IM performance by investigating the reactive processes occurring in the material when subjected to a well-controlled thermal environment. The dominant reactive processes observed were a series of complex chemical interactions between the three main ingredients (DNAN, NQ, and NTO) that occurs well below the onset of the normal decomposition process of any of the individual ingredients. This process shifts the thermal response of the formulations to a much lower temperature, where the kinetically controlled reaction processes are much slower. This low temperature shift has the effect of allowing the reactions to consume the reactive solids (NQ, NTO) well before the reaction rates increase and reach thermal runaway, resulting in a relatively benign response to the external stimuli. The main findings on the interaction processes are presented.

  19. In situ formation of magnetite reactive barriers in soil for waste stabilization

    DOE Patents [OSTI]

    Moore, Robert C. (Edgewood, NM)

    2003-01-01

    Reactive barriers containing magnetite and methods for making magnetite reactive barriers in situ in soil for sequestering soil contaminants including actinides and heavy metals, organic materials, iodine and technetium are disclosed. According to one embodiment, a two-step reagent introduction into soil takes place. In the first step, free oxygen is removed from the soil by separately injecting into the soil aqueous solutions of iron (II) salt, for example FeCl.sub.2, and base, for example NaOH or NH.sub.3 in about a 1:1 volume ratio. Then, in the second step, similar reagents are injected a second time (however, according to about a 1:2 volume ratio, iron to salt) to form magnetite. The magnetite formation is facilitated, in part, due to slow intrusion of oxygen into the soil from the surface. The invention techniques are suited to injection of reagents into soil in proximity to a contamination plume or source allowing in situ formation of the reactive barrier at the location of waste or hazardous material. Mixing of reagents to form. precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

  20. Electronic spectra of 7-azaindole/ammonia clusters and their photochemical reactivity

    SciTech Connect (OSTI)

    Koizumi, Yuna; Norihiro, Tsuji; Ishiuchi, Shun-ichi; Fujii, Masaaki; Jouvet, Christophe; Dedonder-Lardeux, Claude

    2008-09-14

    The S{sub 1}-S{sub 0} electronic spectra of 7-azaindole-(NH{sub 3}){sub n} clusters (n=1-3) were measured by mass-selected two-color resonance-enhanced multiphoton ionization spectroscopy. The laser-induced fluorescence spectrum obtained by monitoring the UV fluorescence shows well-structured vibrational bands for the monomer and 7-azaindole-(NH{sub 3}){sub 1,2} clusters, while no signals appear for the 7-azaindole-(NH{sub 3}){sub 3} cluster. The action spectrum obtained by monitoring visible emission shows no signal for all species, which suggests little reactivity for excited-state proton/hydrogen transfer. From the observed and calculated IR spectra, the geometry of 7-azaindole-(NH{sub 3}){sub 1,2} was concluded to be a hydrogen-bonded bridge form, which is similar to the photochemically reactive 7-hydroxyquinoline-(NH{sub 3}){sub 3} cluster. The difference in the photochemical reactivity is discussed on the basis of excited-state quantum chemical calculations.

  1. Chemical reactivity of CVC and CVD SiC with UO2 at high temperatures

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

    Silva, Chinthaka M; Katoh, Yutai; Voit, Stewart L; Snead, Lance Lewis

    2015-01-01

    Two types of silicon carbide (SiC) synthesized using two different vapor deposition processes were embedded in UO2 pellets and evaluated for their potential chemical reaction with UO2. While minor reactivity between chemical-vapor-composited (CVC) SiC and UO2 was observed at comparatively low temperatures of 1100 and 1300 C, chemical-vapor-deposited (CVD) SiC did not show any such reactivity, according to microstructural investigations. However, both CVD and CVC SiCs showed some reaction with UO2 at a higher temperature (1500 C). Elemental maps supported by phase maps obtained using electron backscatter diffraction indicated that CVC SiC was more reactive than CVD SiC at 1500more » C. Furthermore, this investigation indicated the formation of uranium carbides and uranium silicide chemical phases such as UC, USi2, and U3Si2 as a result of SiC reaction with UO2.« less

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 4, July--September 1987

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1987-10-27

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.

  3. Efficient and Reliable Reactive Power Supply and Consumption --Insights from an Integrated Program of Engineering and EconomicResearch

    SciTech Connect (OSTI)

    Thomas, Robert J.; Mount, Timothy D.; Schuler, Richard; Schulze,William; Zimmerman, Ray; Alvarado, Fernando; Lesieutre, Bernard C.; Overholt, Philip N.; Eto, Joseph H.

    2008-01-01

    In 2005, the Federal Energy Regulatory Commission (FERC) began discussing regulatory policy for reactive-power procurement and pricing in competitive electricity markets. This paper summarizes findings from a unique, interdisciplinary program of public-interest research that lays a formal foundation for evaluating aspects of FERC staff recommendations and offers early insights that should be useful in guiding policy implementation, specifically by: (1) clarifying the consumers and economic characteristics of reactive power as a basis for creating incentives to appropriately price it, (2) defining specific challenges in creating a competitive market for reactive power as well as new tools needed to help ensure such a market functions efficiently, and (3) demonstrating the importance of accounting for the physical characteristics of the transmission network in planning for reactive power and avoiding the exercise of market power by suppliers.

  4. Elastic properties of B-C-N films grown by N{sub 2}-reactive sputtering from boron carbide targets

    SciTech Connect (OSTI)

    Salas, E.; Jiménez Riobóo, R. J.; Jiménez-Villacorta, F.; Prieto, C.; Sánchez-Marcos, J.; Dept. Química-Física Aplicada, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid ; Muñoz-Martín, A.; Prieto, J. E.; Joco, V.

    2013-12-07

    Boron-carbon-nitrogen films were grown by RF reactive sputtering from a B{sub 4}C target and N{sub 2} as reactive gas. The films present phase segregation and are mechanically softer than boron carbide films (a factor of more than 2 in Young's modulus). This fact can turn out as an advantage in order to select buffer layers to better anchor boron carbide films on substrates eliminating thermally induced mechanical tensions.

  5. Pyrolysis process for producing condensed stabilized hydrocarbons utilizing a beneficially reactive gas

    DOE Patents [OSTI]

    Durai-Swamy, Kandaswamy (Culver City, CA)

    1982-01-01

    In a process for recovery of values contained in solid carbonaceous material, the solid carbonaceous material is comminuted and then subjected to pyrolysis, in the presence of a carbon containing solid particulate source of heat and a beneficially reactive transport gas in a transport flash pyrolysis reactor, to form a pyrolysis product stream. The pyrolysis product stream contains a gaseous mixture and particulate solids. The solids are separated from the gaseous mixture to form a substantially solids-free gaseous stream which comprises volatilized hydrocarbon free radicals newly formed by pyrolysis. Preferably the solid particulate source of heat is formed by oxidizing part of the separated particulate solids. The beneficially reactive transport gas inhibits the reactivity of the char product and the carbon-containing solid particulate source of heat. Condensed stabilized hydrocarbons are obtained by quenching the gaseous mixture stream with a quench fluid which contains a capping agent for stabilizing and terminating newly formed volatilized hydrocarbon free radicals. The capping agent is partially depleted of hydrogen by the stabilization and termination reaction. Hydrocarbons of four or more carbon atoms in the gaseous mixture stream are condensed. A liquid stream containing the stabilized liquid product is then treated or separated into various fractions. A liquid containing the hydrogen depleted capping agent is hydrogenated to form a regenerated capping agent. At least a portion of the regenerated capping agent is recycled to the quench zone as the quench fluid. In another embodiment capping agent is produced by the process, separated from the liquid product mixture, and recycled.

  6. Reactivity Accountability Attributed to Reflector Poisons in the High Flux Isotope Reactor

    SciTech Connect (OSTI)

    Chandler, David [ORNL; Maldonado, G Ivan [ORNL; Primm, Trent [ORNL

    2009-12-01

    The objective of this study is to develop a methodology to predict the reactivity impact as a function of outage time between cycles of 3He, 6Li, and other poisons in the High Flux Isotope Reactor s (HFIR) beryllium reflector. The reactivity worth at startup of the HFIR has been incorrectly predicted in the past after the reactor has been shut-down for long periods of time. The incorrect prediction was postulated to be due to the erroneous calculation of 3He buildup in the beryllium reflector. It is necessary to develop a better estimate of the start-of-cycle symmetric critical control element positions since if the estimated and actual symmetrical critical control element positions differ by more than $1.55 in reactivity (approximately one-half inch in control element startup position), HFIR is to be shutdown and a technical evaluation is performed to resolve the discrepancy prior to restart. 3He is generated and depleted during operation, but during an outage, the depletion of 3He ceases because it is a stable isotope. 3He is born from the radioactive decay of tritium, and thus the concentration of 3He increases during shutdown. SCALE, specifically the TRITON and CSAS5 control modules including the KENO V.A, COUPLE, and ORIGEN functional modules were utilized in this study. An equation relating the down time (td) to the change in symmetric control element position was generated and validated against measurements for approximately 40 HFIR operating cycles. The newly-derived correlation was shown to improve accuracy of predictions for long periods of down time.

  7. A Dual Regime Reactive Transport Model for Simulation of High Level Waste Tank Closure Scenarios - 13375

    SciTech Connect (OSTI)

    Sarkar, Sohini; Kosson, David S.; Brown, Kevin; Garrabrants, Andrew C.; Meeussen, Hans; Van der Sloot, Hans

    2013-07-01

    A numerical simulation framework is presented in this paper for estimating evolution of pH and release of major species from grout within high-level waste tanks after closure. This model was developed as part of the Cementitious Barriers Partnership. The reactive transport model consists of two parts - (1) transport of species, and (2) chemical reactions. The closure grout can be assumed to have varying extents of cracking and composition for performance assessment purposes. The partially or completely degraded grouted tank is idealized as a dual regime system comprising of a mobile region having solid materials with cracks and macro-pores, and an immobile/stagnant region having solid matrix with micropores. The transport profiles of the species are calculated by incorporating advection of species through the mobile region, diffusion of species through the immobile/stagnant region, and exchange of species between the mobile and immobile regions. A geochemical speciation code in conjunction with the pH dependent test data for a grout material is used to obtain a mineral set that best describes the trends in the test data of the major species. The dual regime reactive transport model predictions are compared with the release data from an up-flow column percolation test. The coupled model is then used to assess effects of crack state of the structure, rate and composition of the infiltrating water on the pH evolution at the grout-waste interface. The coupled reactive transport model developed in this work can be used as part of the performance assessment process for evaluating potential risks from leaching of a cracked tank containing elements of human health and environmental concern. (authors)

  8. Dynamics of confined reactive water in Smectic clay-zeolite composites.

    SciTech Connect (OSTI)

    Pitman, Michael C.; Van Duin, Adri C. T.

    2012-01-01

    The dynamics of water confined to mesoporous regions in minerals such as swelling clays and zeolites is fundamental to a wide range of resource management issues impacting many processes on a global scale, including radioactive waste containment, desalination, and enhanced oil recovery. Large-scale atomic models of freely diffusing multilayer smectite particles at low hydration confined in a silicalite cage are used to investigate water dynamics in the composite environment with the ReaxFF reactive force field over a temperature range of 300 647 K. The reactive capability of the force field enabled a range of relevant surface chemistry to emerge, including acid/base equilibria in the interlayer calcium hydrates and silanol formation on the edges of the clay and inner surface of the zeolite housing. After annealing, the resulting clay models exhibit both mono- and bilayer hydration structures. Clay surface hydration redistributed markedly and yielded to silicalite water loading. We find that the absolute rates and temperature dependence of water dynamics compare well to neutron scattering data and pulse field gradient measures from relevant samples of Ca-montmorillonite and silicalite, respectively. Within an atomistic, reactive context, our results distinguish water dynamics in the interlayer Ca(OH)2 nH2O environment from water flowing over the clay surface, and from water diffusing within silicalite. We find that the diffusion of water when complexed to Ca hydrates is considerably slower than freely diffusing water over the clay surface, and the reduced mobility is well described by a difference in the Arrhenius pre-exponential factor rather than a change in activation energy.

  9. Dynamics of confined reactive water in smectite clay-zeolite composites

    SciTech Connect (OSTI)

    Pitman, Michael C.; Van Duin, Adri C. T.

    2012-01-01

    The dynamics of water confined to mesoporous regions in minerals such as swelling clays and zeolites is fundamental to a wide range of resource management issues impacting many processes on a global scale, including radioactive waste containment, desalination, and enhanced oil recovery. Large-scale atomic models of freely diffusing multilayer smectite particles at low hydration confined in a silicalite cage are used to investigate water dynamics in the composite environment with the ReaxFF reactive force field over a temperature range of 300 647 K. The reactive capability of the force field enabled a range of relevant surface chemistry to emerge, including acid/base equilibria in the interlayer calcium hydrates and silanol formation on the edges of the clay and inner surface of the zeolite housing. After annealing, the resulting clay models exhibit both mono- and bilayer hydration structures. Clay surface hydration redistributed markedly and yielded to silicalite water loading. We find that the absolute rates and temperature dependence of water dynamics compare well to neutron scattering data and pulse field gradient measures from relevant samples of Ca-montmorillonite and silicalite, respectively. Within an atomistic, reactive context, our results distinguish water dynamics in the interlayer Ca(OH)2 nH2O environment from water flowing over the clay surface, and from water diffusing within silicalite. We find that the diffusion of water when complexed to Ca hydrates is considerably slower than freely diffusing water over the clay surface, and the reduced mobility is well described by a difference in the Arrhenius pre-exponential factor rather than a change in activation energy.

  10. Infiltration processing of boron carbide-, boron-, and boride-reactive metal cermets

    DOE Patents [OSTI]

    Halverson, Danny C. (Manteca, CA); Landingham, Richard L. (Livermore, CA)

    1988-01-01

    A chemical pretreatment method is used to produce boron carbide-, boron-, and boride-reactive metal composites by an infiltration process. The boron carbide or other starting constituents, in powder form, are immersed in various alcohols, or other chemical agents, to change the surface chemistry of the starting constituents. The chemically treated starting constituents are consolidated into a porous ceramic precursor which is then infiltrated by molten aluminum or other metal by heating to wetting conditions. Chemical treatment of the starting constituents allows infiltration to full density. The infiltrated precursor is further heat treated to produce a tailorable microstructure. The process at low cost produces composites with improved characteristics, including increased toughness, strength.

  11. Systems and methods for reactive distillation with recirculation of light components

    DOE Patents [OSTI]

    Stickney, Michael J. (Nassau Bay, TX); Jones, Jr., Edward M. (Friendswood, TX)

    2011-07-26

    Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

  12. Fluidizable zinc titanate materials with high chemical reactivity and attrition resistance

    DOE Patents [OSTI]

    Gupta, R.P.; Gangwal, S.K.; Jain, S.C.

    1993-10-19

    Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 [mu]m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO[sub 3]; and then indurating it at 800 to 900 C for a time sufficient to produce attrition-resistant granules.

  13. Fluidizable zinc titanate materials with high chemical reactivity and attrition resistance

    DOE Patents [OSTI]

    Gupta, Raghubir P.; Gangwal, Santosh K.; Jain, Suresh C.

    1993-01-01

    Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 .mu.m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO.sub.3 ; and then indurating it at 800.degree. to 900.degree. C. for a time sufficient to produce attrition-resistant granules.

  14. A new binder for powder injection molding titanium and other reactive metals

    SciTech Connect (OSTI)

    Weil, K. Scott; Nyberg, Eric A.; Simmons, Kevin L.

    2006-06-26

    We have developed a new aromatic-based binder for powder injection molding (PIM) reactive metals, such as titanium, zirconium, niobium, tungsten, and molybdenum. Because of careful selection of the binder constituents, thermal removal is readily accomplished at low temperatures and short-times via vacuum sublimation. In this way the binder can be cleanly extracted from the green part prior to sintering to minimize the amount of residual carbon left in the final component. Rheological measurements indicate that powder loadings in the PIM feedstock as high as 67 vol% could be achieved using the new binder system, while still maintaining low mixing torques and injection molding pressures.

  15. Chemical Reactivity Testing for the National Spent Nuclear Fuel Program. Quality Assurance Project Plan

    SciTech Connect (OSTI)

    Newsom, H.C.

    1999-01-24

    This quality assurance project plan (QAPjP) summarizes requirements used by Lockheed Martin Energy Systems, Incorporated (LMES) Development Division at Y-12 for conducting chemical reactivity testing of Department of Energy (DOE) owned spent nuclear fuel, sponsored by the National Spent Nuclear Fuel Program (NSNFP). The requirements are based on the NSNFP Statement of Work PRO-007 (Statement of Work for Laboratory Determination of Uranium Hydride Oxidation Reaction Kinetics.) This QAPjP will utilize the quality assurance program at Y-12, QA-101PD, revision 1, and existing implementing procedures for the most part in meeting the NSNFP Statement of Work PRO-007 requirements, exceptions will be noted.

  16. Cytotoxicity of InP/ZnS quantum dots related to reactive oxygen species generation.

    SciTech Connect (OSTI)

    Chibli, H.; Carlini, L.; Park, S.; Dimitrijevic, N. M.; Nadeau, J. L.

    2011-01-01

    Indium phosphide (InP) quantum dots (QDs) have emerged as a presumably less hazardous alternative to cadmium-based particles, but their cytotoxicity has not been well examined. Although their constituent elements are of very low toxicity to cells in culture, they nonetheless exhibit phototoxicity related to generation of reactive oxygen species by excited electrons and/or holes interacting with water and molecular oxygen. Using spin-trap electron paramagnetic resonance (EPR) spectroscopy and reporter assays, we find a considerable amount of superoxide and a small amount of hydroxyl radical formed under visible illumination of biocompatible InP QDs with a single ZnS shell, comparable to what is seen with CdTe. A double thickness shell reduces the reactive oxygen species concentration approximately two-fold. Survival assays in five cell lines correspondingly indicate a distinct reduction in toxicity with the double-shell InP QDs. Toxicity varies significantly across cell lines according to the efficiency of uptake, being overall significantly less than what is seen with CdTe or CdSe/ZnS. This indicates that InP QDs are a useful alternative to cadmium-containing QDs, while remaining capable of electron-transfer processes that may be undesirable or which may be exploited for photosensitization applications.

  17. Hysteresis-free high rate reactive sputtering of niobium oxide, tantalum oxide, and aluminum oxide

    SciTech Connect (OSTI)

    Särhammar, Erik, E-mail: erik.sarhammar@angstrom.uu.se; Berg, Sören; Nyberg, Tomas [Department of Solid State Electronics, The Ångström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden)

    2014-07-01

    This work reports on experimental studies of reactive sputtering from targets consisting of a metal and its oxide. The composition of the targets varied from pure metal to pure oxide of Al, Ta, and Nb. This combines features from both the metal target and oxide target in reactive sputtering. If a certain relation between the metal and oxide parts is chosen, it may be possible to obtain a high deposition rate, due to the metal part, and a hysteresis-free process, due to the oxide part. The aim of this work is to quantify the achievable boost in oxide deposition rate from a hysteresis-free process by using a target consisting of segments of a metal and its oxide. Such an increase has been previously demonstrated for Ti using a homogeneous substoichiometric target. The achievable gain in deposition rate depends on transformation mechanisms from oxide to suboxides due to preferential sputtering of oxygen. Such mechanisms are different for different materials and the achievable gain is therefore material dependent. For the investigated materials, the authors have demonstrated oxide deposition rates that are 1.5–10 times higher than what is possible from metal targets in compound mode. However, although the principle is demonstrated for oxides of Al, Ta, and Nb, a similar behavior is expected for most oxides.

  18. A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions

    SciTech Connect (OSTI)

    Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C; Brooks, Scott C; Pace, Molly; Kim, Young Jin; Jardine, Philip M; Watson, David B

    2007-01-01

    This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

  19. Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation

    SciTech Connect (OSTI)

    Wu, Y.; Ajo-Franklin, J.B.; Spycher, N.; Hubbard, S.S.; Zhang, G.; Williams, K.H.; Taylor, J.; Fujita, Y.; Smith, R.

    2011-07-15

    Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH{sub 4}{sup +} production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

  20. Geophysical Monitoring and Reactive Transport Modeling of Ureolytically-Driven Calcium Carbonate Precipitation

    SciTech Connect (OSTI)

    Yuxin Wu; Jonathan B. Ajo-Franklin; Nicolas Spycher; Susan S. Hubbard; Guoxiang Zhang; Kenneth H. Williams; Joanna Taylor; Yoshiko Fujita; Robert Smith

    2011-09-01

    Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH4+ production during urea hydrolysis were incorporated in the model and captured critical changes in the major metal species. The electrical phase increases were potentially due to ion exchange processes that modified charge structure at mineral/water interfaces. Our study revealed the potential of geophysical monitoring for geochemical changes during urea hydrolysis and the advantages of combining multiple approaches to understand complex biogeochemical processes in the subsurface.

  1. QUANTIFICATION OF FUGITIVE REACTIVE ALKENE EMISSIONS FROM PETROCHEMICAL PLANTS WITH PERFLUOROCARBON TRACERS.

    SciTech Connect (OSTI)

    SENUM,G.I.; DIETZ,R.N.

    2004-06-30

    Recent studies demonstrate the impact of fugitive emissions of reactive alkenes on the atmospheric chemistry of the Houston Texas metropolitan area (1). Petrochemical plants located in and around the Houston area emit atmospheric alkenes, such as ethene, propene and 1,3-butadiene. The magnitude of emissions is a major uncertainty in assessing their effects. Even though the petrochemical industry reports that fugitive emissions of alkenes have been reduced to less than 0.1% of daily production, recent measurement data, obtained during the TexAQS 2000 experiment indicates that emissions are perhaps a factor of ten larger than estimated values. Industry figures for fugitive emissions are based on adding up estimated emission factors for every component in the plant to give a total estimated emission from the entire facility. The dramatic difference between estimated and measured rates indicates either that calculating emission fluxes by summing estimates for individual components is seriously flawed, possibly due to individual components leaking well beyond their estimated tolerances, that not all sources of emissions for a facility are being considered in emissions estimates, or that there are known sources of emissions that are not being reported. This experiment was designed to confirm estimates of reactive alkene emissions derived from analysis of the TexAQS 2000 data by releasing perfluorocarbon tracers (PFTs) at a known flux from a petrochemical plant and sampling both the perfluorocarbon tracer and reactive alkenes downwind using the Piper-Aztec research aircraft operated by Baylor University. PFTs have been extensively used to determine leaks in pipelines, air infiltration in buildings, and to characterize the transport and dispersion of air parcels in the atmosphere. Over 20 years of development by the Tracer Technology Center (TTC) has produced a range of analysis instruments, field samplers and PFT release equipment that have been successfully deployed in a large variety of experiments. PFTs are inert, nontoxic, noncombustible and nonreactive. Up to seven unique PFTs can be simultaneously released, sampled and analyzed and the technology is well suited for determining emission fluxes from large petrochemical facilities. The PFT experiment described here was designed to quantitate alkene emissions from a single petrochemical facility, but such experiments could be applied to other industrial sources or groups of sources in the Houston area.

  2. Assessment of Controlling Processes for Field-Scale Uranium Reactive Transport under Highly Transient Flow Conditions

    SciTech Connect (OSTI)

    Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan; Greskowiak, Janek; Prommer, Henning; Zachara, John M.

    2014-02-13

    This paper presents the results of a comprehensive model-based analysis of a uranium tracer test conducted at the U.S Department of Energy Hanford 300 Area (300A) IFRC site. A three-dimensional multi-component reactive transport model was employed to assess the key factors and processes that control the field-scale uranium reactive transport. Taking into consideration of relevant physical and chemical processes, the selected conceptual/numerical model replicates the spatial and temporal variations of the observed U(VI) concentrations reasonably well in spite of the highly complex field conditions. A sensitivity analysis was performed to interrogate the relative importance of various processes and factors for reactive transport of U(VI) at the field-scale. The results indicate that multi-rate U(VI) sorption/desorption, U(VI) surface complexation reactions, and initial U(VI) concentrations were the most important processes and factors controlling U(VI) migration. On the other hand, cation exchange reactions, the choice of the surface complexation model, and dual-domain mass transfer processes, which were previously identified to be important in laboratory experiments, played less important roles under the field-scale experimental condition at the 300A site. However, the model simulations also revealed that the groundwater chemistry was relatively stable during the uranium tracer experiment and therefore presumably not dynamic enough to appropriately assess the effects of ion exchange reaction and the choice of surface complexation models on U(VI) sorption and desorption. Furthermore, it also showed that the field experimental duration (16 days) was not sufficiently long to precisely assess the role of a majority of the sorption sites that were accessed by slow kinetic processes within the dual domain model. The sensitivity analysis revealed the crucial role of the intraborehole flow that occurred within the long-screened monitoring wells and thus significantly affected both field-scale measurements and simulated U(VI) concentrations as a combined effect of aquifer heterogeneity and highly dynamic flow conditions. Overall, this study, which provides one of the few detailed and highly data-constrained uranium transport simulations, highlights the difference in controlling processes between laboratory and field scale that prevent a simple direct upscaling of laboratory-scale models.

  3. Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation’s Cañon City, Colorado, Uranium Mill

    Broader source: Energy.gov [DOE]

    Performance Assessment and Recommendations for Rejuvenation of a Permeable Reactive Barrier: Cotter Corporation’s Canon City, Colorado, Uranium Mill (April 2005)

  4. Catalytic reactive separation system for energy-efficient production of cumene

    DOE Patents [OSTI]

    Buelna, Genoveva; Nenoff, Tina M.

    2009-07-28

    The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

  5. Reactive triblock polymers from tandem ring-opening polymerization for nanostructured vinyl thermosets

    SciTech Connect (OSTI)

    Amendt, Mark A.; Pitet, Louis M.; Moench, Sarah; Hillmyer, Marc A.

    2013-03-07

    Multiply functional hydroxyl telechelic poly(cyclooctene-s-5-norbornene-2-methylene methacrylate) was synthesized by ring opening metathesis (co)polymerization of cis-cyclooctene and 5-norbornene-2-methylene methacrylate using the second generation Grubbs catalyst in combination with a symmetric chain transfer agent bearing hydroxyl functionality. The resulting hydroxyl-telechelic polymer was used as a macroinitiator for the ring opening transesterification polymerization of d,l-lactide to form reactive poly(lactide)-b-poly(cyclooctene-s-5-norbornene-2-methylene methacrylate)-b-poly(lactide) triblock polymers. Subsequently, the triblocks were crosslinked by free radical copolymerization with several vinyl monomers including styrene, divinylbenzene, methyl methacrylate, and ethyleneglycol dimethacrylate. Certain conditions led to optically transparent thermosets with mesoscale phase separation as evidenced by small angle X-ray scattering, differential scanning calorimetry and transmission electron microscopy. Disordered, bicontinuous structures with nanoscopic domains were generated in several cases, rendering the samples attractive for size-selective membrane applications.

  6. Structural and thermal properties of nanocrystalline CuO synthesized by reactive magnetron sputtering

    SciTech Connect (OSTI)

    Verma, M.; Gupta, V. K.; Gautam, Y. K.; Dave, V.; Chandra, R.

    2014-01-28

    Recent research has shown immense application of metal oxides like CuO, MgO, CaO, Al{sub 2}O{sub 3}, etc. in different areas which includes chemical warfare agents, medical drugs, magnetic storage media and solar energy transformation. Among the metal oxides, CuO nanoparticles are of special interest because of their excellent gas sensing and catalytic properties. In this paper we report structural and thermal properties of CuO synthesized by reactive magnetron DC sputtering. The synthesized nanoparticles were characterized by X-ray diffractometer. The XRD result reveals that as DC power increased from 30W to 80W, size of the CuO nanoparticles increased. The same results have been verified through TEM analysis. Thermal properties of these particles were studied using thermogravimetry.

  7. Organic/inorganic nanocomposites, methods of making, and uses as a permeable reactive barrier

    DOE Patents [OSTI]

    Harrup, Mason K.; Stewart, Frederick F.

    2007-05-15

    Nanocomposite materials having a composition including an inorganic constituent, a preformed organic polymer constituent, and a metal ion sequestration constituent are disclosed. The nanocomposites are characterized by being single phase, substantially homogeneous materials wherein the preformed polymer constituent and the inorganic constituent form an interpenetrating network with each other. The inorganic constituent may be an inorganic oxide, such as silicon dioxide, formed by the in situ catalyzed condensation of an inorganic precursor in the presence of the solvated polymer and metal ion sequestration constituent. The polymer constituent may be any hydrophilic polymer capable of forming a type I nanocomposite such as, polyacrylonitrile (PAN), polyethyleneoxide (PEO), polyethylene glycol (PEG), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), and combinations thereof. Nanocomposite materials of the present invention may be used as permeable reactive barriers (PRBs) to remediate contaminated groundwater. Methods for making nanocomposite materials, PRB systems, and methods of treating groundwater are also disclosed.

  8. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID)

    1997-01-01

    A method for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap therebetween. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition.

  9. Method for cracking hydrocarbon compositions using a submerged reactive plasma system

    DOE Patents [OSTI]

    Kong, P.C.

    1997-05-06

    A method is described for cracking a liquid hydrocarbon composition (e.g. crude oil) to produce a cracked hydrocarbon product. A liquid hydrocarbon composition is initially provided. An electrical arc is generated directly within the hydrocarbon composition so that the arc is entirely submerged in the composition. Arc generation is preferably accomplished using a primary and secondary electrode each having a first end submerged in the composition. The first ends of the electrodes are separated from each other to form a gap there between. An electrical potential is then applied to the electrodes to generate the arc within the gap. A reactive gas is thereafter delivered to the arc which forms a bubble around the arc. Gas delivery may be accomplished by providing a passageway through each electrode and delivering the gas through the passageways. The arc and gas cooperate to produce a plasma which efficiently cracks the hydrocarbon composition. 6 figs.

  10. Reduced yield stress for zirconium exposed to iodine: Reactive force field simulation

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

    Rossi, Matthew L.; Taylor, Christopher D.; van Duin, Adri C. T.

    2014-11-04

    Iodine-induced stress-corrosion cracking (ISCC), a known failure mode for nuclear fuel cladding, occurs when iodine generated during the irradiation of a nuclear fuel pellet escapes the pellet through diffusion or thermal cracking and chemically interacts with the inner surface of the clad material, inducing a subsequent effect on the cladding’s resistance to mechanical stress. To complement experimental investigations of ISCC, a reactive force field (ReaxFF) compatible with the Zr-I chemical and materials systems has been developed and applied to simulate the impact of iodine exposure on the mechanical strength of the material. The study shows that the material’s resistance tomore » stress (as captured by the yield stress of a high-energy grain boundary) is related to the surface coverage of iodine, with the implication that ISCC is the result of adsorption-enhanced decohesion.« less

  11. Boron-carbide-aluminum and boron-carbide-reactive metal cermets

    DOE Patents [OSTI]

    Halverson, Danny C. (Manteca, CA); Pyzik, Aleksander J. (Seattle, WA); Aksay, Ilhan A. (Seattle, WA)

    1986-01-01

    Hard, tough, lightweight boron-carbide-reactive metal composites, particularly boron-carbide-aluminum composites, are produced. These composites have compositions with a plurality of phases. A method is provided, including the steps of wetting and reacting the starting materials, by which the microstructures in the resulting composites can be controllably selected. Starting compositions, reaction temperatures, reaction times, and reaction atmospheres are parameters for controlling the process and resulting compositions. The ceramic phases are homogeneously distributed in the metal phases and adhesive forces at ceramic-metal interfaces are maximized. An initial consolidation step is used to achieve fully dense composites. Microstructures of boron-carbide-aluminum cermets have been produced with modulus of rupture exceeding 110 ksi and fracture toughness exceeding 12 ksi.sqroot.in. These composites and methods can be used to form a variety of structural elements.

  12. Methods for modeling impact-induced reactivity changes in small reactors.

    SciTech Connect (OSTI)

    Tallman, Tyler N.; Radel, Tracy E.; Smith, Jeffrey A.; Villa, Daniel L.; Smith, Brandon M.; Radel, Ross F.; Lipinski, Ronald J.; Wilson, Paul Philip Hood

    2010-10-01

    This paper describes techniques for determining impact deformation and the subsequent reactivity change for a space reactor impacting the ground following a potential launch accident or for large fuel bundles in a shipping container following an accident. This technique could be used to determine the margin of subcriticality for such potential accidents. Specifically, the approach couples a finite element continuum mechanics model (Pronto3D or Presto) with a neutronics code (MCNP). DAGMC, developed at the University of Wisconsin-Madison, is used to enable MCNP geometric queries to be performed using Pronto3D output. This paper summarizes what has been done historically for reactor launch analysis, describes the impact criticality analysis methodology, and presents preliminary results using representative reactor designs.

  13. Studies on optoelectronic properties of DC reactive magnetron sputtered chromium doped CdO thin films

    SciTech Connect (OSTI)

    Hymavathi, B. Rao, T. Subba; Kumar, B. Rajesh

    2014-10-15

    Cr doped CdO thin films were deposited on glass substrates by DC reactive magnetron sputtering method and subsequently annealed from 200 °C to 500 °C. X-ray diffraction analysis showed that the films exhibit (1 1 1) preferred orientation. The optical transmittance of the films increases from 64% to 88% with increasing annealing temperature. The optical band gap values were found to be decreased from 2.77 to 2.65 eV with the increase of annealing temperature. The decrease in optical band gap energy with increasing annealing temperature can be attributed to improvement in the crystallinity of the films and may also be due to quantum confinement effect. A minimum resistivity of 2.23 × 10{sup ?4} ?.cm and sheet resistance of 6.3 ?/sq is obtained for Cr doped CdO film annealed at 500 °C.

  14. Tuning Reactivity and Electronic Properties through Ligand Reorganization within a Cerium Heterobimetallic Framework

    SciTech Connect (OSTI)

    Robinson, Jerome R.; Gordon, Zachary; Booth, Corwin H.; Carroll, Patrick J.; Walsh, Patrick J.; Schelter, Eric J.

    2014-06-24

    Cerium compounds have played vital roles in organic, inorganic, and materials chemistry due to their reversible redox chemistry between trivalent and tetravalent oxidation states. However, attempts to rationally access molecular cerium complexes in both oxidation states have been frustrated by unpredictable reactivity in cerium(III) oxidation chemistry. Such oxidation reactions are limited by steric saturation at the metal ion, which can result in high energy activation barriers for electron transfer. An alternative approach has been realized using a rare earth/alkali metal/1,1'-BINOLate (REMB) heterobimetallic framework, which uses redox-inactive metals within the secondary coordination sphere to control ligand reorganization. The rational syntheses of functionalized cerium(IV) products and a mechanistic examination of the role of ligand reorganization in cerium(III) oxidation are presented.

  15. Utility of reactively sputtered CuN{sub x} films in spintronics devices

    SciTech Connect (OSTI)

    Fang Yeyu; Persson, J.; Zha, C.; Willman, J.; Miller, Casey W.; Aakerman, Johan

    2012-04-01

    We have studied nitrified copper (CuN{sub x}) thin films grown by reactive sputtering in the context of spintronic devices. The Ar-to-N{sub 2} flow ratio enables tunability of the electrical resistivity and surface roughness of the CuN{sub x} films, with the former increasing to nearly 20 times that of Cu, and the latter reduced to the atomic scale. Incorporating this into a Ta/CuN{sub x}/Ta seed stack for spin valves improves the current-in-plane (CIP) magnetoresistance; maximum magnetoresistance results with CuN{sub x} seed layer and Cu interlayer. Finally, finite element modeling results are presented that suggest the use of CuN{sub x} in nanocontact spin torque oscillators can enhance current densities by limiting the current spread through the device. This may positively impact threshold currents, power requirements, and device reliability.

  16. Chemical reactivity testing for the National Spent Nuclear Fuel Program. Revision 2

    SciTech Connect (OSTI)

    Koester, L.W.

    2000-02-08

    This quality assurance project plan (QAPjP) summarizes requirements used by Lockheed Martin Energy Systems, Incorporated (LMES) Development Division at Y-12 for conducting chemical reactivity testing of Department of Energy (DOE) owned spent nuclear fuel, sponsored by the National Spent Nuclear Fuel Program (NSNFP). The requirements are based on the NSNFP Statement of work PRO-007 (Statement of Work for Laboratory Determination of Uranium Hydride Oxidation Reaction Kinetics.) This QAPjP will utilize the quality assurance program at Y-12, Y60-101PD, Quality Program Description, and existing implementing procedures for the most part in meeting the NSNFP Statement of Work PRO-007 requirements, exceptions will be noted. The project consists of conducting three separate series of related experiments, ''Passivation of Uranium Hydride Powder With Oxygen and Water'', '''Passivation of Uranium Hydride Powder with Surface Characterization'', and ''Electrochemical Measure of Uranium Hydride Corrosion Rate''.

  17. Integrated atomistic chemical imaging and reactive force field molecular dynamic simulations on silicon oxidation

    SciTech Connect (OSTI)

    Dumpala, Santoshrupa; Broderick, Scott R.; Rajan, Krishna; Khalilov, Umedjon; Neyts, Erik C.; Duin, Adri C. T. van; Provine, J; Howe, Roger T.

    2015-01-05

    In this paper, we quantitatively investigate with atom probe tomography, the effect of temperature on the interfacial transition layer suboxide species due to the thermal oxidation of silicon. The chemistry at the interface was measured with atomic scale resolution, and the changes in chemistry and intermixing at the interface were identified on a nanometer scale. We find an increase of suboxide (SiOx) concentration relative to SiO{sub 2} and increased oxygen ingress with elevated temperatures. Our experimental findings are in agreement with reactive force field molecular dynamics simulations. This work demonstrates the direct comparison between atom probe derived chemical profiles and atomistic-scale simulations for transitional interfacial layer of suboxides as a function of temperature.

  18. Reduced yield stress for zirconium exposed to iodine: Reactive force field simulation

    SciTech Connect (OSTI)

    Rossi, Matthew L.; Taylor, Christopher D.; van Duin, Adri C. T.

    2014-11-04

    Iodine-induced stress-corrosion cracking (ISCC), a known failure mode for nuclear fuel cladding, occurs when iodine generated during the irradiation of a nuclear fuel pellet escapes the pellet through diffusion or thermal cracking and chemically interacts with the inner surface of the clad material, inducing a subsequent effect on the cladding’s resistance to mechanical stress. To complement experimental investigations of ISCC, a reactive force field (ReaxFF) compatible with the Zr-I chemical and materials systems has been developed and applied to simulate the impact of iodine exposure on the mechanical strength of the material. The study shows that the material’s resistance to stress (as captured by the yield stress of a high-energy grain boundary) is related to the surface coverage of iodine, with the implication that ISCC is the result of adsorption-enhanced decohesion.

  19. Method for atmospheric pressure reactive atom plasma processing for surface modification

    DOE Patents [OSTI]

    Carr, Jeffrey W.

    2009-09-22

    Reactive atom plasma processing can be used to shape, polish, planarize and clean the surfaces of difficult materials with minimal subsurface damage. The apparatus and methods use a plasma torch, such as a conventional ICP torch. The workpiece and plasma torch are moved with respect to each other, whether by translating and/or rotating the workpiece, the plasma, or both. The plasma discharge from the torch can be used to shape, planarize, polish, and/or clean the surface of the workpiece, as well as to thin the workpiece. The processing may cause minimal or no damage to the workpiece underneath the surface, and may involve removing material from the surface of the workpiece.

  20. Modeling carbon nanotube growth on the catalyst-substrate surface subjected to reactive plasma [

    SciTech Connect (OSTI)

    Tewari, Aarti; Sharma, Suresh C.

    2014-06-15

    The paper presents a theoretical model to study the growth of the carbon nanotube (CNT) on the catalyst substrate surface subjected to reactive plasma. The charging rate of the CNT, kinetics of electron, ions and neutral atoms, the growth rate of the CNT because of diffusion and accretion of ions on the catalyst nanoparticle inclusion of the issue of the plasma sheath is undertaken in the present model. Numerical calculations on the effect of ion density and temperature and the substrate bias on the growth of the CNT have been carried out for typical glow discharge plasma parameters. It is found that the height of CNT increases with the ion density of carbon ions and radius of CNT decreases with hydrogen ion density. The substrate bias also affects the growth rate of the CNT. The field emission characteristics from the CNTs can be analyzed from the results obtained.

  1. Internal neutronics-temperature coupling in Serpent 2 - Reactivity differences resulting from choice of material property correlations

    SciTech Connect (OSTI)

    Valtavirta, V. [VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT (Finland)

    2013-07-01

    This paper describes the unique way of simultaneously solving the power and temperature distributions of a nuclear system with the Monte Carlo neutron transport code Serpent 2. The coupled solution is achieved through the implementation of an internal temperature solver and material property correlations in the code. The program structure is reviewed concerning the temperature solver and the internal correlations as well as the internal coupling between these two and the neutron transport part. To estimate the reactivity differences resulting from correlation choices a simple pin-cell case has been calculated. It is established, that some correlation choices may result in difference in reactivity of approximately 100 pcm. (authors)

  2. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 8, July--September 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  3. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 9, October--December 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-03-06

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  4. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report No. 3, April--June 1987

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  5. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 2, January--March 1987

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  6. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  7. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 7, April--June 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  8. Modular High-Temperature Gas-Cooled Reactor short term thermal response to flow and reactivity transients

    SciTech Connect (OSTI)

    Cleveland, J.C.

    1988-01-01

    The analyses reported here have been conducted at the Oak Ridge National Laboratory (ORNL) for the US Nuclear Regulatory Commission's (NRC's) Division of Regulatory Applications of the Office of Nuclear Regulatory Research. The short-term thermal response of the Modular High-Temperature Gas-Cooled Reactor (MHTGR) is analyzed for a range of flow and reactivity transients. These include loss of forced circulation (LOFC) without scram, moisture ingress, spurious withdrawal of a control rod group, hypothetical large and rapid positive reactivity insertion, and a rapid core cooling event. The coupled heat transfer-neutron kinetics model is also described.

  9. Quantum Theory of (H,H{Sub 2}) Scattering: Approximate Treatments of Reactive Scattering

    DOE R&D Accomplishments [OSTI]

    Tang, K. T.; Karplus, M.

    1970-10-01

    A quantum mechanical study is made of reactive scattering in the (H, H{sub 2}) system. The problem is formulated in terms of a form of the distorted-wave Born approximation (DWBA) suitable for collisions in which all particles have finite mass. For certain incident energies, differential and total cross sections, as well as other attributes of the reactive collisions, (e.g. reaction configuration), are determined. Two limiting models in the DWBA formulation are compared; in one, the molecule is unperturbed by the incoming atom and in the other, the molecule adiabatically follows the incoming atom. For thermal incident energies and semi-empirical interaction potential employed, the adiabatic model seems to be more appropriate. Since the DWBA method is too complicated for a general study of the (H, H{sub 2}) reaction, a much simpler approximation method, the “linear model” is developed. This model is very different in concept from treatments in which the three atoms are constrained to move on a line throughout the collision. The present model includes the full three-dimensional aspect of the collision and it is only the evaluation of the transition matrix element itself that is simplified. It is found that the linear model, when appropriately normalized, gives results in good agreement with that of the DWBA method. By application of this model, the energy dependence, rotational state of dependence and other properties of the total and differential reactions cross sections are determined. These results of the quantum mechanical treatment are compared with the classical calculation for the same potential surface. The most important result is that, in agreement with the classical treatment, the differential cross sections are strongly backward peaked at low energies and shifts in the forward direction as the energy increases. Finally, the implications of the present calculations for a theory of chemical kinetics are discussed.

  10. Coupled reactive mass transport and fluid flow: Issues in model verification

    SciTech Connect (OSTI)

    Freedman, Vicky L.; Ibaraki, Motomu

    2003-01-03

    Model verification and validation are both important steps in the development of reactive transport models. In this paper, a distinction is made between verification and validation, and the focus is on codifying the issues of verification for a numerical, reactive transport flow model. First, the conceptual basis of model verification is reviewed, which shows that verification should be understood as a first step in model development, and be followed by a protocol that assures that the model accurately represents system behavior. Second, commonly used procedures and methods of model verification are presented. In the third part of this paper, an intercomparison of models is used to demonstrate that model verification can be performed despite differences in hydrogeochemical transport code formulations. Results of an example simulation of transport are presented in which the numerical model is tested against other hydrogeochemical codes. Different kinetic formulations between solid and aqueous phases used among numerical models complicates model verification. This test problem involves uranium transport under conditions of varying pH and oxidation potential, with reversible precipitation of calcium uranate and coffinite. Results between the different hydrogeochemical transport codes show differences in oxidation potentials, but similarities in mineral assemblages and aqueous transport patterns. Because model verification can be further complicated by differences in the approach for solving redox problems, a comparison of a fugacity approach to both the external approach (based on hypothetical electron activity) and effective internal approach (based on conservation of electrons) is performed. The comparison demonstrates that the oxygen fugacity approach produces different redox potentials and mineral assemblages than both the effective internal and external approaches.

  11. A sequential partly iterative approach for multicomponent reactive transport with CORE2D

    SciTech Connect (OSTI)

    Samper, J.; Xu, T.; Yang, C.

    2008-11-01

    CORE{sup 2D} V4 is a finite element code for modeling partly or fully saturated water flow, heat transport and multicomponent reactive solute transport under both local chemical equilibrium and kinetic conditions. It can handle coupled microbial processes and geochemical reactions such as acid-base, aqueous complexation, redox, mineral dissolution/precipitation, gas dissolution/exsolution, ion exchange, sorption via linear and nonlinear isotherms, sorption via surface complexation. Hydraulic parameters may change due to mineral precipitation/dissolution reactions. Coupled transport and chemical equations are solved by using sequential iterative approaches. A sequential partly-iterative approach (SPIA) is presented which improves the accuracy of the traditional sequential noniterative approach (SNIA) and is more efficient than the general sequential iterative approach (SIA). While SNIA leads to a substantial saving of computing time, it introduces numerical errors which are especially large for cation exchange reactions. SPIA improves the efficiency of SIA because the iteration between transport and chemical equations is only performed in nodes with a large mass transfer between solid and liquid phases. The efficiency and accuracy of SPIA are compared to those of SIA and SNIA using synthetic examples and a case study of reactive transport through the Llobregat Delta aquitard in Spain. SPIA is found to be as accurate as SIA while requiring significantly less CPU time. In addition, SPIA is much more accurate than SNIA with only a minor increase in computing time. A further enhancement of the efficiency of SPIA is achieved by improving the efficiency of the Newton-Raphson method used for solving chemical equations. Such an improvement is obtained by working with increments of log-concentrations and ignoring the terms of the Jacobian matrix containing derivatives of activity coefficients. A proof is given for the symmetry and non-singularity of the Jacobian matrix. Numerical analyses performed with synthetic examples confirm that these modifications improve the efficiency and convergence of the iterative algorithm.

  12. Characterization of the chemical reactivity and nephrotoxicity of N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide, a potential reactive metabolite of trichloroethylene

    SciTech Connect (OSTI)

    Irving, Roy M.; Pinkerton, Marie E.; Elfarra, Adnan A.

    2013-02-15

    N-Acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NA-DCVC) has been detected in the urine of humans exposed to trichloroethylene and its related sulfoxide, N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (NA-DCVCS), has been detected as hemoglobin adducts in blood of rats dosed with S-(1,2-dichlorovinyl)-L-cysteine (DCVC) or S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (DCVCS). Because the in vivo nephrotoxicity of NA-DCVCS was unknown, in this study, male Sprague–Dawley rats were dosed (i.p.) with 230 ?mol/kg b.w. NA-DCVCS or its potential precursors, DCVCS or NA-DCVC. At 24 h post treatment, rats given NA-DCVC or NA-DCVCS exhibited kidney lesions and effects on renal function distinct from those caused by DCVCS. NA-DCVC and NA-DCVCS primarily affected the cortico-medullary proximal tubules (S{sub 2}–S{sub 3} segments) while DCVCS primarily affected the outer cortical proximal tubules (S{sub 1}–S{sub 2} segments). When NA-DCVCS or DCVCS was incubated with GSH in phosphate buffer pH 7.4 at 37 °C, the corresponding glutathione conjugates were detected, but NA-DCVC was not reactive with GSH. Because NA-DCVCS exhibited a longer half-life than DCVCS and addition of rat liver cytosol enhanced GSH conjugate formation, catalysis of GSH conjugate formation by the liver could explain the lower toxicity of NA-DCVCS in comparison with DCVCS. Collectively, these results provide clear evidence that NA-DCVCS formation could play a significant role in DCVC, NA-DCVC, and trichloroethylene nephrotoxicity. They also suggest a role for hepatic metabolism in the mechanism of NA-DCVC nephrotoxicity. - Highlights: ? NA-DCVCS and NA-DCVC toxicity are distinct from DCVCS toxicity. ? NA-DCVCS readily reacts with GSH to form mono- and di-GSH conjugates. ? Liver glutathione S-transferases enhance NA-DCVCS GSH conjugate formation. ? Renal localization of lesions suggests a role for NA-DCVCS in TCE nephrotoxicity.

  13. Manipulating Interfaces through Surface Confinement of Poly(glycidyl methacrylate)-block-poly(vinyldimethylazlactone), a Dually Reactive Block Copolymer

    SciTech Connect (OSTI)

    Lokitz, Bradley S; Wei, Jifeng; Hinestrosa Salazar, Juan P; Ivanov, Ilia N; Browning, James B; Ankner, John Francis; Kilbey, II, S Michael; Messman, Jamie M

    2012-01-01

    The assembly of dually reactive, well-defined diblock copolymers incorporating the chemoselective/functional monomer, 4,4-dimethyl-2-vinylazlactone (VDMA) and the surface-reactive monomer glycidyl methacrylate (GMA) is examined to understand how competition between surface attachment and microphase segregation influences interfacial structure. Reaction of the PGMA block with surface hydroxyl groups not only anchors the copolymer to the surface, but limits chain mobility, creating brush-like structures comprising PVDMA blocks, which contain reactive azlactone groups. The block copolymers are spin coated at various solution concentrations and annealed at elevated temperature to optimize film deposition to achieve a molecularly uniform layer. The thickness and structure of the polymer thin films are investigated by ellipsometry, infrared spectroscopy, and neutron reflectometry. The results show that deposition of PGMA-b-PVDMA provides a useful route to control film thickness while preserving azlactone groups that can be further modified with biotin-poly(ethylene glycol)amine to generate designer surfaces. The method described herein offers guidance for creating highly functional surfaces, films, or coatings through the use of dually reactive block copolymers and postpolymerization modification.

  14. Direct measurement of the chemical reactivity of silicon electrodes with LiPF6-based battery electrolytes

    SciTech Connect (OSTI)

    Veith, Gabriel M; Baggetto, Loic; Sacci, Robert L; Unocic, Raymond R; Tenhaeff, Wyatt E; Browning, Jim

    2014-01-01

    We report the first direct measurement of the chemistry and extent of reactivity between a lithium ion battery electrode surface (Si) and a liquid electrolyte (1.2M LiPF6-3:7 wt% ethylene carbonate:dimethyl carbonate). This layer is estimated to be 3.6 nm thick and partially originates from the consumption of the silicon surface.

  15. Best Practices for Operando Battery Experiments: Influences of X-ray Experiment Design on Observed Electrochemical Reactivity

    SciTech Connect (OSTI)

    Borkiewicz, O. J.; Wiaderek, Kamila M.; Chupas, Peter J.; Chapman, Karena W.

    2015-06-04

    Dynamic properties and multiscale complexities governing electrochemical energy storage in batteries are most ideally interrogated under simulated operating conditions within an electrochemical cell. We assess how electrochemical reactivity can be impacted by experiment design, including the X-ray measurements or by common features or adaptations of electrochemical cells that enable X-ray measurements.

  16. Soft Landing of Mass-Selected Gold Clusters: Influence of Ion and Ligand on Charge Retention and Reactivity

    SciTech Connect (OSTI)

    Johnson, Grant E.; Laskin, Julia

    2015-02-01

    Herein, we employ a combination of reduction synthesis in solution, soft landing of mass-selected precursor and product ions, and in situ time-of-flight secondary ion mass spectrometry (TOF-SIMS) to examine the influence of ion and the length of diphosphine ligands on the charge retention and reactivity of ligated gold clusters deposited onto self-assembled monolayer surfaces (SAMs). Product ions (Au10L42+, (10,4)2+, L = 1,3-bis(diphenyl-phosphino)propane, DPPP) were prepared through in-source collision induced dissociation (CID) and precursor ions [(8,4)2+, L = 1,6-bis(diphenylphosphino)hexane, DPPH] were synthesized in solution for comparison to (11,5)3+ precursor ions ligated with DPPP investigated previously (ACS Nano 2012, 6, 573 and J. Phys. Chem. C. 2012, 116, 24977). Similar to (11,5)3+ precursor ions, the (10,4)2+ product ions are shown to retain charge on 1H,1H,2H,2H-perfluorodecanethiol monolayers (FSAMs). Additional abundant peaks at higher m/z indicative of reactivity are observed in the TOF-SIMS spectrum of (10,4)2+ product ions that are not seen for (11,5)3+ precursor ions. The abundance of (10,4)2+ on 16-mercaptohexadecanoic acid (COOH-SAMs) is demonstrated to be lower than on FSAMs, consistent with partial reduction of charge. The (10,4)2+ product ion on 1-dodecanethiol (HSAMs) exhibits peaks similar to those seen on the COOH-SAM. On the HSAM, higher m/z peaks indicative of reactivity are observed similar to those on the FSAM. The (8,4)2+ DPPH precursor ions are shown to retain charge on FSAMs similar to (11,5)3+ precursor ions prepared with DPPP. An additional peak corresponding to attachment of one gold atom to (8,4)2+ is observed at higher m/z for DPPH-ligated clusters. On the COOH-SAM, (8,4)2+ is less abundant than on the FSAM consistent with partial neutralization. The results indicate that although retention of charge by product ions generated by CID is similar to precursor ions their reactivity during analysis with SIMS is different resulting in the formation of peaks corresponding to reaction products. The length of the ligand exerts only a minor influence on the charge retention and reactivity of gold clusters. Based on the observed reactivity of (10,4)2+ it is anticipated that in-source CID will be increasingly applied for the preparation of a distribution of product ions, including undercoordinated and reactive species, for soft landing onto surfaces.

  17. Performance of Trasuranic-Loaded Fully Ceramic Micro-Encapsulated Fuel in LWRs Interim Report, Including Void Reactivity Evaluation

    SciTech Connect (OSTI)

    Michael A. Pope; Brian Boer; Gilles Youinou; Abderrafi M. Ougouag

    2011-03-01

    The current focus of the Deep Burn Project is on once-through burning of transuranice (TRU) in light water reactors (LWRs). The fuel form is called Fully-Ceramic Micro-encapsulated (FCM) fuel, a concept that borrows the tri-isotropic (TRISO) fuel particle design from high-temperature reactor technology. In the Deep Burn LWR (DB-LWR) concept, these fuel particles would be pressed into compacts using SiC matrix material and loaded into fuel pins for use in conventional LWRs. The TRU loading comes from the spent fuel of a conventional LWR after 5 years of cooling. Unit cell calculations have been performed using the DRAGON-4 code in order assess the physics attributes of TRU-only FCM fuel in an LWR lattice. Depletion calculations assuming an infinite lattice condition were performed with calculations of various reactivity coefficients performed at each step. Unit cells containing typical UO2 and MOX fuel were analyzed in the same way to provide a baseline against which to compare the TRU-only FCM fuel. Loading of TRU-only FCM fuel into a pin without significant quantities of uranium challenges the design from the standpoint of several key reactivity parameters, particularly void reactivity, and to some degree, the Doppler coefficient. These unit cells, while providing an indication of how a whole core of similar fuel would behave, also provide information of how individual pins of TRU-only FCM fuel would influence the reactivity behavior of a heterogeneous assembly. If these FCM fuel pins are included in a heterogeneous assembly with LEU fuel pins, the overall reactivity behavior would be dominated by the uranium pins while attractive TRU destruction performance of the TRU-only FCM fuel pins may be preserved. A configuration such as this would be similar to CONFU assemblies analyzed in previous studies. Analogous to the plutonium content limits imposed on MOX fuel, some amount of TRU-only FCM pins in an otherwise-uranium fuel assembly may give acceptable reactivity performance. Assembly calculations will be performed in future work to explore the design options for heterogeneous assemblies of this type and their impact on reactivity coefficients.

  18. Pebble Fuel Handling and Reactivity Control for Salt-Cooled High Temperature Reactors

    SciTech Connect (OSTI)

    Peterson, Per; Greenspan, Ehud

    2015-02-09

    This report documents the work completed on the X-PREX facility under NEUP Project 11- 3172. This project seeks to demonstrate the viability of pebble fuel handling and reactivity control for fluoride salt-cooled high-temperature reactors (FHRs). The research results also improve the understanding of pebble motion in helium-cooled reactors, as well as the general, fundamental understanding of low-velocity granular flows. Successful use of pebble fuels in with salt coolants would bring major benefits for high-temperature reactor technology. Pebble fuels enable on-line refueling and operation with low excess reactivity, and thus simpler reactivity control and improved fuel utilization. If fixed fuel designs are used, the power density of salt- cooled reactors is limited to 10 MW/m3 to obtain adequate duration between refueling, but pebble fuels allow power densities in the range of 20 to 30 MW/m3. This can be compared to the typical modular helium reactor power density of 5 MW/m3. Pebble fuels also permit radial zoning in annular cores and use of thorium or graphite pebble blankets to reduce neutron fluences to outer radial reflectors and increase total power production. Combined with high power conversion efficiency, compact low-pressure primary and containment systems, and unique safety characteristics including very large thermal margins (>500°C) to fuel damage during transients and accidents, salt-cooled pebble fuel cores offer the potential to meet the major goals of the Advanced Reactor Concepts Development program to provide electricity at lower cost than light water reactors with improved safety and system performance.This report presents the facility description, experimental results, and supporting simulation methods of the new X-Ray Pebble Recirculation Experiment (X-PREX), which is now operational and being used to collect data on the behavior of slow dense granular flows relevant to pebble bed reactor core designs. The X-PREX facility uses novel digital x-ray tomography methods to track both the translational and rotational motion of spherical pebbles, which provides unique experimental results that can be used to validate discrete element method (DEM) simulations of pebble motion. The validation effort supported by the X-PREX facility provides a means to build confidence in analysis of pebble bed configuration and residence time distributions that impact the neutronics, thermal hydraulics, and safety analysis of pebble bed reactor cores. Experimental and DEM simulation results are reported for silo drainage, a classical problem in the granular flow literature, at several hopper angles. These studies include conventional converging and novel diverging geometries that provide additional flexibility in the design of pebble bed reactor cores. Excellent agreement is found between the X-PREX experimental and DEM simulation results. This report also includes results for additional studies relevant to the design and analysis of pebble bed reactor cores including the study of forces on shut down blades inserted directly into a packed bed and pebble flow in a cylindrical hopper that is representative of a small test reactor.

  19. Methanol Oxidative Dehydrogenation on Oxide Catalysts: Molecular and Dissociative Routes and Hydrogen Addition Energies as Descriptors of Reactivity

    SciTech Connect (OSTI)

    Deshlahra, Prashant; Iglesia, Enrique

    2014-11-13

    The oxidative dehydrogenation (ODH) of alkanols on oxide catalysts is generally described as involving H-abstraction from alkoxy species formed via O–H dissociation. Kinetic and isotopic data cannot discern between such routes and those involving kinetically-relevant H-abstraction from undissociated alkanols. Here, we combine such experiments with theoretical estimates of activation energies and entropies to show that the latter molecular routes prevail over dissociative routes for methanol reactions on polyoxometalate (POM) clusters at all practical reaction temperatures. The stability of the late transition states that mediate H-abstraction depend predominantly on the stability of the O–H bond formed, making H-addition energies (HAE) accurate and single-valued descriptors of reactivity. Density functional theory-derived activation energies depend linearly on HAE values at each O-atom location on clusters with a range of composition (H3PMo12, H4SiMo12, H3PW12, H4PV1Mo11, and H4PV1W11); both barriers and HAE values reflect the lowest unoccupied molecular orbital energy of metal centers that accept the electron and the protonation energy of O-atoms that accept the proton involved in the H-atom transfer. Bridging O-atoms form O–H bonds that are stronger than those of terminal atoms and therefore exhibit more negative HAE values and higher ODH reactivity on all POM clusters. For each cluster composition, ODH turnover rates reflect the reactivity-averaged HAE of all accessible O-atoms, which can be evaluated for each cluster composition to provide a rigorous and accurate predictor of ODH reactivity for catalysts with known structure. These relations together with oxidation reactivity measurements can then be used to estimate HAE values and to infer plausible structures for catalysts with uncertain active site structures.

  20. WETTING AND REACTIVE AIR BRAZING OF BSCF FOR OXYGEN SEPARATION DEVICES

    SciTech Connect (OSTI)

    LaDouceur, Richard M.; Meier, Alan; Joshi, Vineet V.

    2014-10-13

    Reactive air brazes Ag-CuO and Ag-V2O5 were evaluated for brazing Ba0.5Sr0.5Co0.8Fe0.2O(3-?) (BSCF). BSCF has been determined in previous work to have the highest potential mixed ionic/electronic conducting (MIEC) ceramic material based on the design and oxygen flux requirements of an oxy-fuel plant such as an integrated gasification combined cycle (IGCC) used to facilitate high-efficiency carbon capture. Apparent contact angles were observed for Ag-CuO and Ag-V2O5 mixtures at 1000 °C for isothermal hold times of 0, 10, 30, and 60 minutes. Wetting apparent contact angles (?<90°) were obtained for 1%, 2%, and 5% Ag-CuO and Ag-V2O5 mixtures, with the apparent contact angles between 74° and 78° for all compositions and furnace dwell times. Preliminary microstructural analysis indicates that two different interfacial reactions are occurring: Ag-CuO interfacial microstructures revealed the same dissolution of copper oxide into the BSCF matrix to form copper-cobalt-oxygen rich dissolution products along the BSCF grain boundaries and Ag-V2O5 interfacial microstructures revealed the infiltration and replacement of cobalt and iron with vanadium and silver filling pores in the BSCF microstructure. The Ag-V2O5 interfacial reaction product layer was measured to be significantly thinner than the Ag-CuO reaction product layer. Using a fully articulated four point flexural bend test fixture, the flexural fracture strength for BSCF was determined to be 95 ± 33 MPa. The fracture strength will be used to ascertain the success of the reactive air braze alloys. Based on these results, brazes were fabricated and mechanically tested to begin to optimize the brazing parameters for this system. Ag-2.5% CuO braze alloy with a 2.5 minute thermal cycle achieved a hermetic seal with a joint flexural strength of 34 ± 15 MPa and Ag-1% V2O5 with a 30 minute thermal cycle had a joint flexural strength of 20 ± 15 MPa.

  1. An example of neutronic penalizations in reactivity transient analysis using 3D coupled chain HEMERA

    SciTech Connect (OSTI)

    Dubois, F.; Normand, B.; Sargeni, A.

    2012-07-01

    HEMERA (Highly Evolutionary Methods for Extensive Reactor Analyses), is a fully coupled 3D computational chain developed jointly by IRSN and CEA. It is composed of CRONOS2 (core neutronics, cross sections library from APOLLO2), FLICA4 (core thermal-hydraulics) and the system code CATHARE. Multi-level and multi-dimensional models are developed to account for neutronics, core thermal-hydraulics, fuel thermal analysis and system thermal-hydraulics, dedicated to best-estimate, conservative simulations and sensitivity analysis. In IRSN, the HEMERA chain is widely used to study several types of reactivity accidents and for sensitivity studies. Just as an example of the HEMERA possibilities, we present here two types of neutronic penalizations and their impact on a power transient due to a REA (Rod Ejection Accident): in the first one, we studied a bum-up distribution modification and in the second one, a delayed-neutron fraction modification. Both modifications are applied to the whole core or localized in a few assemblies. Results show that it is possible to use global or local changes but 1) in case of bum-up modification, the total core power can increase when assembly peak power decrease so, care has to be taken if the goal is to maximize a local power peak and 2) for delayed-neutron fraction, a local modification can have the same effect as the one on the whole core, provided that it is large enough. (authors)

  2. Poster — Thur Eve — 74: Distributed, asynchronous, reactive dosimetric and outcomes analysis using DICOMautomaton

    SciTech Connect (OSTI)

    Clark, Haley; Wu, Jonn; Moiseenko, Vitali; Thomas, Steven

    2014-08-15

    Many have speculated about the future of computational technology in clinical radiation oncology. It has been advocated that the next generation of computational infrastructure will improve on the current generation by incorporating richer aspects of automation, more heavily and seamlessly featuring distributed and parallel computation, and providing more flexibility toward aggregate data analysis. In this report we describe how a recently created — but currently existing — analysis framework (DICOMautomaton) incorporates these aspects. DICOMautomaton supports a variety of use cases but is especially suited for dosimetric outcomes correlation analysis, investigation and comparison of radiotherapy treatment efficacy, and dose-volume computation. We describe: how it overcomes computational bottlenecks by distributing workload across a network of machines; how modern, asynchronous computational techniques are used to reduce blocking and avoid unnecessary computation; and how issues of out-of-date data are addressed using reactive programming techniques and data dependency chains. We describe internal architecture of the software and give a detailed demonstration of how DICOMautomaton could be used to search for correlations between dosimetric and outcomes data.

  3. Uranium metal reactions with hydrogen and water vapour and the reactivity of the uranium hydride produced

    SciTech Connect (OSTI)

    Godfrey, H.; Broan, C.; Goddard, D.; Hodge, N.; Woodhouse, G.; Diggle, A.; Orr, R.

    2013-07-01

    Within the nuclear industry, metallic uranium has been used as a fuel. If this metal is stored in a hydrogen rich environment then the uranium metal can react with the hydrogen to form uranium hydride which can be pyrophoric when exposed to air. The UK National Nuclear Laboratory has been carrying out a programme of research for Sellafield Limited to investigate the conditions required for the formation and persistence of uranium hydride and the reactivity of the material formed. The experimental results presented here have described new results characterising uranium hydride formed from bulk uranium at 50 and 160 C. degrees and measurements of the hydrolysis kinetics of these materials in liquid water. It has been shown that there is an increase in the proportion of alpha-uranium hydride in material formed at lower temperatures and that there is an increase in the rate of reaction with water of uranium hydride formed at lower temperatures. This may at least in part be attributable to a difference in the reaction rate between alpha and beta-uranium hydride. A striking observation is the strong dependence of the hydrolysis reaction rate on the temperature of preparation of the uranium hydride. For example, the reaction rate of uranium hydride prepared at 50 C. degrees was over ten times higher than that prepared at 160 C. degrees at 20% extent of reaction. The decrease in reaction rate with the extent of reaction also depended on the temperature of uranium hydride preparation.

  4. Photodetachment and electron reactivity in 1-methyl-1-butyl-pyrrolidinium bis(trifluoromethylsulfonyl)amide

    SciTech Connect (OSTI)

    Molins i Domenech, Francesc; FitzPatrick, Benjamin; Healy, Andrew T.; Blank, David A.

    2012-07-21

    The transient absorption spectrum in the range 500 nm-1000 nm was measured with ultrafast time resolution on a flowing neat, aliphatic, room-temperature ionic liquid following anion photodetachment. In this region the spectrum was shown to be a combination of absorption from the electron and the hole. Spectrally-resolved electron quenching determined a bimodal shape for the hole spectrum in agreement with recent computational predictions on a smaller aliphatic ionic liquid [Margulis et al., J. Am. Chem. Soc. 133, 20186 (2011)]. For time delays beyond 15 ps, spectral evolution qualitatively agrees with recent radiolysis experiments [Wishart et al., Faraday Discuss. 154, 353 (2012)]. However, the shape of the spectrum is different, reflecting the contrast in ionization energy between the two methods. Previously unobserved reactivity of the electron was found with a time constant of 300 fs. The results demonstrate solvent control of the rate coefficient for reaction between the electron and proton, with a rapid decline in the rate within the first picosecond.

  5. Modelling On Photogeneration Of Hydroxyl Radical In Surface Waters And Its Reactivity Towards Pharmaceutical Wastes

    SciTech Connect (OSTI)

    Das, Radha; Vione, Davide; Rubertelli, Francesca; Maurino, Valter; Minero, Claudio; Barbati, Stephane; Chiron, Serge

    2010-10-26

    This paper reports a simple model to describe the formation and reactivity of hydroxyl radicals in the whole column of freshwater lakes. It is based on empirical irradiation data and is a function of the water chemical composition (the photochemically significant parameters NPOC, nitrate, nitrite, carbonate and bicarbonate), the lake conformation best expressed as the average depth, and the water absorption spectrum in a simplified Lambert-Beer approach. The purpose is to derive the lifetime of dissolved molecules, due to reaction with OH, on the basis of their second-order rate constants with the hydroxyl radical. The model was applied to two compounds of pharmaceutical wastes ibuprofen and carbamazepine, for which the second-order rate constants for reaction with the hydroxyl radical were measured by means of the competition kinetics with 2-propanol. The measured values of the rate constants are 1.0x10{sup 10} and 1.6x10{sup 10} M{sup -1} s{sup -1} for ibuprofen and carbamazepine, respectively. The model suggests that the lifetime of a given compound can be very variable in different lakes, even more than the lifetime of different compounds in the same lake. It can be concluded that as far as the reaction with OH, is concerned the concepts of photolability and photostability, traditionally attached to definite compounds, are ecosystem-dependent at least as much as they depend on the molecule under consideration.

  6. Reactive chemical transport in ground-water hydrology: Challenges to mathematical modeling

    SciTech Connect (OSTI)

    Narasimhan, T.N.; Apps, J.A.

    1990-07-01

    For a long time, earth scientists have qualitatively recognized that mineral assemblages in soils and rocks conform to established principles of chemistry. In the early 1960's geochemists began systematizing this knowledge by developing quantitative thermodynamic models based on equilibrium considerations. These models have since been coupled with advective-dispersive-diffusive transport models, already developed by ground-water hydrologists. Spurred by a need for handling difficult environmental issues related to ground-water contamination, these models are being improved, refined and applied to realistic problems of interest. There is little doubt that these models will play an important role in solving important problems of engineering as well as science over the coming years. Even as these models are being used practically, there is scope for their improvement and many challenges lie ahead. In addition to improving the conceptual basis of the governing equations, much remains to be done to incorporate kinetic processes and biological mediation into extant chemical equilibrium models. Much also remains to be learned about the limits to which model predictability can be reasonably taken. The purpose of this paper is to broadly assess the current status of knowledge in modeling reactive chemical transport and to identify the challenges that lie ahead.

  7. Structural and optical properties of DC reactive magnetron sputtered zinc aluminum oxide thin films

    SciTech Connect (OSTI)

    Kumar, B. Rajesh; Rao, T. Subba

    2014-10-15

    Highly transparent conductive Zinc Aluminum Oxide (ZAO) thin films have been deposited on glass substrates using DC reactive magnetron sputtering method. The thin films were deposited at 200 °C and post-deposition annealing from 15 to 90 min. XRD patterns of ZAO films exhibit only (0 0 2) diffraction peak, indicating that they have c-axis preferred orientation perpendicular to the substrate. Scanning electron microscopy (SEM) is used to study the surface morphology of the films. The grain size obtained from SEM images of ZAO thin films are found to be in the range of 20 - 26 nm. The minimum resistivity of 1.74 × 10{sup ?4} ? cm and an average transmittance of 92% are obtained for the thin film post annealed for 30 min. The optical band gap of ZAO thin films increased from 3.49 to 3.60 eV with the increase of annealing time due to Burstein-Moss effect. The optical constants refractive index (n) and extinction coefficient (k) were also determined from the optical transmission spectra.

  8. Understanding composite explosive energetics: 3, Reactive flow modeling of aluminum reaction kinetics in PETN and TNT

    SciTech Connect (OSTI)

    Tao, W.C.; Tarver, C.M.; Ornellas, D.L.

    1991-12-06

    Using Fabry-Perot interferometry techniques, we have determined that early time rate of energy release from detonating PETN and TNT explosives filled with 5 and 10 wt % of either 5 {mu}m of 18 {mu}m spherical aluminum (Al) particles. From the measured particle velocity data, we are able to infer the reaction rate of aluminum with the detonation products, and calculate the extent of reaction 1--3 {mu}s after the detonation. We observed that a substantional portion of the aluminum metal in all of the PETN and TNE formulations reacted within the timeframe of the one-dimensional experiment. In the PETN formulation filed with 5 wt % of 5 {mu}m aluminum, all of the metal reacted within 1.5 {mu}s, resulting in an increase of 22% in energy compared to pure PETN. A reactive-flow hydrodynamic model based on the Zeldovich-von Neumann-Doring (ZND) description of the reaction zone and subsequent reaction produce expansion (Taylor wave) is used to interpret the reaction rate of the aluminum particles with detonation product gases. The diffusion-controlled reaction mechanism for aluminum and the global kinetic parameters used in the model have been found to be consistent for all the PETN and TNT formulations.

  9. Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

    SciTech Connect (OSTI)

    Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

    2011-09-01

    Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

  10. Isolation of Metals from Liquid Wastes: Reactive Scavenging in Turbulent Thermal Reactors

    SciTech Connect (OSTI)

    William Linak

    2004-12-16

    Sorption of cesium and strontium on kaolinite powders was investigated as a means to minimize the emissions of these metals during certain high temperature processes currently being developed to isolate and dispose of radiological and mixed wastes. In this work, non-radioactive aqueous cesium acetate or strontium acetate was atomized down the center of a natural gas flame supported on a variable-swirl burner in a refractory-lined laboratory-scale combustion facility. Kaolinite powder was injected at a post-flame location in the combustor. Cesium readily vaporizes in the high temperature regions of the combustor, but was reactively scavenged onto dispersed kaolinite. Global sorption mechanisms of cesium vapor on kaolinite were quantified, and are related to those available in the literature for sodium and lead. Both metal adsorption and substrate deactivation steps are important, and so there is an optimum temperature, between 1400 and 1500 K, at which maximum sorption occurs. The presence of chlorine inhibits cesium sorption. In contrast to cesium, and in the absence of chlorine, strontium was only partially vaporized and was, therefore, only partially scavengeable. The strontium data did not allow quantification of global kinetic mechanisms of interaction, although equilibrium arguments provided insight into the effects of chlorine on strontium sorption. These results have implications for the use of sorbents to control cesium and strontium emissions during high temperature waste processing including incineration and vitrification.

  11. Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    SciTech Connect (OSTI)

    Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; O���¢��������Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

    2012-11-05

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

  12. FUNDAMENTAL ENVIRONMENTAL REACTIVITY TESTING AND ANALYSIS OF THE HYDROGEN STORAGE MATERIAL 2LIBH4 MGH2

    SciTech Connect (OSTI)

    James, C.; Anton, D.; Cortes-Concepcion, J.; Brinkman, K.; Gray, J.

    2012-01-10

    While the storage of hydrogen for portable and stationary applications is regarded as critical in bringing PEM fuel cells to commercial acceptance, little is known of the environmental exposure risks posed in utilizing condensed phase chemical storage options as in complex hydrides. It is thus important to understand the effect of environmental exposure of metal hydrides in the case of accident scenarios. Simulated tests were performed following the United Nations standards to test for flammability and water reactivity in air for a destabilized lithium borohydride and magnesium hydride system in a 2 to 1 molar ratio respectively. It was determined that the mixture acted similarly to the parent, lithium borohydride, but at slower rate of reaction seen in magnesium hydride. To quantify environmental exposure kinetics, isothermal calorimetry was utilized to measure the enthalpy of reaction as a function of exposure time to dry and humid air, and liquid water. The reaction with liquid water was found to increase the heat flow significantly during exposure compared to exposure in dry or humid air environments. Calorimetric results showed the maximum normalized heat flow the fully charged material was 6 mW/mg under liquid phase hydrolysis; and 14 mW/mg for the fully discharged material also occurring under liquid phase hydrolysis conditions.

  13. Reaction-Based Reactive Transport Modeling of Fe(III) and U(V) Reduction

    SciTech Connect (OSTI)

    Burgos, William D.; Roden, Eric E.; Yeh, Gour-Tsyh

    2005-06-01

    Our new research project (started Fall 2004) was funded by a grant to The Pennsylvania State University, University of Central Florida, and The University of Alabama in the Integrative Studies Element of the NABIR Program (DE-FG04-ER63914/63915/63196). Our previous NABIR project (DE-FG02-01ER63180/63181/63182, funded within the Biotransformation Element) focused on (1) microbial reduction of Fe(III) and U(VI) individually, and concomitantly in natural sediments, (2) Fe(III) oxide surface chemistry, specifically with respect to reactions with Fe(II) and U(VI), (3) the influence of humic substances on Fe(III) and U(VI) bioreduction, and on U(VI) complexation, and (4) the development of reaction-based reactive transport biogeochemical models to numerically simulate our experimental results. The new project focuses on the development of a mechanistic understanding and quantitative models of coupled Fe(III)/U(VI) reduction in FRC Area 2 sediments. This work builds on our previous studies of microbial Fe(III) and U(VI) reduction, and is directly aligned with the Scheibe et al. NABIR FRC Field Project at Area 2.

  14. Semianalytical Solutions of Radioactive or Reactive Tracer Transport in Layered Fractured Media

    SciTech Connect (OSTI)

    G.J. Moridis; G. S. Bodvarsson

    2001-10-01

    In this paper, semianalytical solutions are developed for the problem of transport of radioactive or reactive tracers (solutes or colloids) through a layered system of heterogeneous fractured media with misaligned fractures. The tracer transport equations in the matrix account for (a) diffusion, (b) surface diffusion (for solutes only), (c) mass transfer between the mobile and immobile water fractions, (d) linear kinetic or equilibrium physical, chemical, or combined solute sorption or colloid filtration, and (e) radioactive decay or first order chemical reactions. Any number of radioactive decay daughter products (or products of a linear, first-order reaction chain) can be tracked. The tracer-transport equations in the fractures account for the same processes, in addition to advection and hydrodynamic dispersion. Additionally, the colloid transport equations account for straining and velocity adjustments related to the colloidal size. The solutions, which are analytical in the Laplace space, are numerically inverted to provide the solution in time and can accommodate any number of fractured and/or porous layers. The solutions are verified using analytical solutions for limiting cases of solute and colloid transport through fractured and porous media. The effect of important parameters on the transport of {sup 3}H, {sup 237}Np and {sup 239}Pu (and its daughters) is investigated in several test problems involving layered geological systems of varying complexity. {sup 239}Pu colloid transport problems in multilayered systems indicate significant colloid accumulations at straining interfaces but much faster transport of the colloid than the corresponding strongly sorbing solute species.

  15. Effectiveness of Diesel Oxidation Catalyst in Reducing HC and CO Emissions from Reactivity Controlled Compression Ignition

    SciTech Connect (OSTI)

    Prikhodko, Vitaly Y; Curran, Scott; Parks, II, James E; Wagner, Robert M

    2013-01-01

    Reactivity Controlled Compression Ignition (RCCI) has been shown to allow for diesel-like or better brake thermal efficiency with significant reductions in nitrogen oxide (NOX) particulate matter (PM) emissions. Hydrocarbon (HC) and carbon monoxide (CO) emission levels, on the other hand, are similar to those of port fuel injected gasoline engines. The higher HC and CO emissions combined with the lower exhaust temperatures with RCCI operation present a challenge for current exhaust aftertreatments. The reduction of HC and CO emissions in a lean environment is typically achieved with an oxidation catalyst. In this work, several diesel oxidation catalysts (DOC) with different precious metal loadings were evaluated for effectiveness to control HC and CO emissions from RCCI combustion in a light-duty multi-cylinder engine operating on gasoline and diesel fuels. Each catalyst was evaluated in a steady-state engine operation with temperatures ranging from 160 to 260 C. A shift to a higher light-off temperature was observed during the RCCI operation. In addition to the steady-state experiments, the performances of the DOCs were evaluated during multi-mode engine operation by switching from diesel-like combustion at higher exhaust temperature and low HC/CO emissions to RCCI combustion at lower temperature and higher HC/CO emissions. High CO and HC emissions from RCCI generated an exotherm keeping the catalyst above the light-off temperature.

  16. Installation of a reactive site for covalent wiring onto an intrinsically conductive poly(ionic liquid)

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

    Brombosz, Scott M.; Lee, Sungwon; Firestone, Millicent A.

    2014-11-04

    We describe post-polymerization radical bromination of a nanostructured poly(ionic liquid) that selectively introduces a reactive bromo-group onto the polyalkylthiophene backbone. Raman and FT-IR spectroscopy proves that the bromine is successfully introduced at the 3-methyl position of the thiophene and that the molecular structure of the polymer remains largely intact with only minimal chain scission detected. FT-IR and Vis-NIR spectroscopy indicates that incorporation of the bromine induces twisting (loss of co-planarity) of the polythiophene backbone. WAXS confirms retention of an ordered lamellar structure with minor lattice spacing contraction. Cyclic voltammetry confirms spectroscopic findings that the bromination reaction yields a stable p-dopedmore » polymer. The installed bromine is susceptible to nucleophilic displacement permitting the covalent attachment of other functional molecules, such as a dialkylphosphonate. Elemental analysis of such a transformation established that 100 % functionalization can be achieved. These results collectively demonstrate that post-modification of a π-conjugated polymer can be used to both tune electronic and photonic properties, as well as install a chemoselective attachment point for the covalent wiring of other molecules.« less

  17. Analysis of molten fuel-coolant interaction during a reactivity-initiated accident experiment. [BWR; PWR

    SciTech Connect (OSTI)

    El-Genk, M.S.; Hobbins, R.R.

    1981-01-01

    The results of a reactivity-initiated accident experiment, designated RIA-ST-4, are discussed and analyzed with regard to molten fuel-coolant interaction (MFCI). In this experiment, extensive amounts of molten UO/sub 2/ fuel and zircaloy cladding were produced and fragmented upon mixing with the coolant. Coolant pressurization up to 35 MPa and coolant overheating in excess of 940 K occurred after fuel rod failure. The initial coolant conditions were similar to those in boiling water reactors during a hot startup (that is, coolant pressure of 6.45 MPa, coolant temperature of 538 K, and coolant flow rate of 85 cm/sup 3//s). It is concluded that the high coolant pressure recorded in the RIA-ST-4 experiment was caused by an energetic MFCI and was not due to gas release from the test rod at failure, Zr/water reaction, or to UO/sub 2/ fuel vapor pressure. The high coolant temperature indicated the presence of superheated steam, which may have formed during the expansion of the working fluid back to the initial coolant pressure; yet, the thermal-to-mechanical energy conversion ratio is estimated to be only 0.3%.

  18. High-Burnup BWR Fuel Behavior Under Simulated Reactivity-Initiated Accident Conditions

    SciTech Connect (OSTI)

    Nakamura, Takehiko; Kusagaya, Kazuyuki; Fuketa, Toyoshi; Uetsuka, Hiroshi

    2002-06-15

    Boiling water reactor (BWR) fuel at 56 to 61 GWd/tonne U was pulse irradiated in the Nuclear Safety Research Reactor (NSRR) to investigate fuel behavior under cold startup reactivity-initiated accident conditions. Current Japanese 8 x 8 type Step II BWR fuel from Fukushima Daini Unit 2 was refabricated to short segments, and thermal energy from 272 to 586 J/g (65 to 140 cal/g) was promptly inserted to the test rods. Cladding deformation of the BWR fuel by the pulse irradiation was smaller than that of pressurized water reactor (PWR) fuels. However, cladding failure occurred in tests with fuel at burnup of 61 GWd/tonne U at fuel enthalpies of 260 to 360 J/g (62 to 86 cal/g) during the early stages of transients, while the cladding remained cool. The failure was comparable to the one observed in high-burnup PWR fuel tests, in which embrittled cladding with dense hydride precipitation near the outer surface was fractured due to pellet cladding mechanical interaction. Transient fission gas release by the pulse irradiation was {approx}9.6 to 17% depending on the peak fuel enthalpy.

  19. Controllable generation of reactive oxygen species by femtosecond-laser irradiation

    SciTech Connect (OSTI)

    Yan, Wei; He, Hao Wang, Yintao; Wang, Yisen; Hu, Minglie; Wang, Chingyue

    2014-02-24

    Femtosecond lasers have been advancing Biophotonics research in the past two decades with multiphoton microscopy, microsurgery, and photodynamic therapy. Nevertheless, laser irradiation is identified to bring photodamage to cells via reactive oxygen species (ROS) generation with unclear mechanism. Meanwhile, currently in biological researches, there is no effective method to provide controllable ROS production precisely, which originally is leaked from mitochondria during respiration and plays a key role in a lot of important cellular processes and cellular signaling pathways. In this study, we show the process of how the tightly focused femtosecond-laser induces ROS generation solely in mitochondria at the very beginning and then release to cytosol if the stimulus is intense enough. At certain weak power levels, the laser pulses induce merely moderate Ca{sup 2+} release but this is necessary for the laser to generate ROS in mitochondria. Cellular original ROS are also involved with a small contribution. When the power is above a threshold, ROS are then released to cytosol, indicating photodamage overwhelming cellular repair ability. The mechanisms in those two cases are quite different. Those results clarify parts of the mechanism in laser-induced ROS generation. Hence, it is possible to further this optical scheme to provide controllable ROS generation for ROS-related biological researches including mitochondrial diseases and aging.

  20. A transparent Pyrex ?-reactor for combined in situ optical characterization and photocatalytic reactivity measurements

    SciTech Connect (OSTI)

    Dionigi, F.; Hansen, O.; Department of Micro- and Nanotechnology, Nanotech, Building 345 East, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby ; Nielsen, M. G.; Chorkendorff, I.; Vesborg, P. C. K.; Pedersen, T.

    2013-10-15

    A new Pyrex-based ?-reactor for photocatalytic and optical characterization experiments is presented. The reactor chamber and gas channels are microfabricated in a thin poly-silicon coated Pyrex chip that is sealed with a Pyrex lid by anodic bonding. The device is transparent to light in the UV-vis-near infrared range of wavelengths (photon energies between ?0.4 and ?4.1 eV). The absorbance of a photocatalytic film obtained with a light transmission measurement during a photocatalytic reaction is presented as a proof of concept of a photocatalytic reactivity measurement combined with in situ optical characterization. Diffuse reflectance measurements of highly scattering photocatalytic nanopowders in a sealed Pyrex ?-reactor are also possible using an integrating sphere as shown in this work. These experiments prove that a photocatalyst can be characterized with optical techniques after a photocatalytic reaction without removing the material from the reactor. The catalyst deposited in the cylindrical reactor chamber can be illuminated from both top and bottom sides and an example of application of top and bottom illumination is presented.

  1. Formation, Migration, and Reactivity of Au CO Complexes on Gold Surfaces

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

    Wang, Jun; McEntee, Monica; Tang, Wenjie; Neurock, Matthew; Baddorf, Arthur P.; Maksymovych, Petro; Yates, Jr, John T.

    2016-01-12

    Here, we report experimental as well as theoretical evidence that suggests Au CO complex formation upon the exposure of CO to active sites (step edges and threading dislocations) on a Au(111) surface. Room-temperature scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy, transmission infrared spectroscopy, and density functional theory calculations point to Au CO complex formation and migration. Room-temperature STM of the Au(111) surface at CO pressures in the range from 10^ 8 to 10^ 4 Torr (dosage up to 10^6 langmuir) indicates Au atom extraction from dislocation sites of the herringbone reconstruction, mobile Au CO complex formation and diffusion, and Aumore » adatom cluster formation on both elbows and step edges on the Au surface. The formation and mobility of the Au CO complex result from the reduced Au Au bonding at elbows and step edges leading to stronger Au CO bonding and to the formation of a more positively charged CO (CO +) on Au. These studies indicate that the mobile Au CO complex is involved in the Au nanoparticle formation and reactivity, and that the positive charge on CO increases due to the stronger adsorption of CO at Au sites with lower coordination numbers.« less

  2. Thermal stability and oxygen-loss characteristics of Pt(O) films prepared by reactive sputtering

    SciTech Connect (OSTI)

    Saenger, K.L.; Cabral, C. Jr.; Lavoie, C.; Rossnagel, S.M.

    1999-12-01

    Pt(O) films having compositions ranging from pure Pt to amorphous platinum oxide a-PtO{sub x} (x{approximately}1.4) were prepared by reactive sputtering and examined during and after heating to temperatures used for deposition and processing of high-epsilon (HE) and ferroelectric (FE) materials (400{endash}650&hthinsp;{degree}C). A two stage decomposition process was observed for a-PtO{sub x} (x{approximately}1.4) films heated in N{sub 2}, with the first stage of decomposition beginning at temperatures well below 400&hthinsp;{degree}C. In an O{sub 2} ambient, decomposition was accompanied by formation of a crystalline Pt{sub 3}O{sub 4} phase prior to complete decomposition to metallic Pt. However, the relatively slow rate of oxygen loss from a-PtO{sub x} suggests that significant amounts of oxygen should remain in Pt(O) electrodes after HE/FE layer deposition. {copyright} {ital 1999 American Institute of Physics.}

  3. Voltage control for a wind power plant based on the available reactive current of a DFIG and its impacts on the point of interconnection

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

    Usman, Yasir; Kim, Jinho; Muljadi, Eduard; Kang, Yong Cheol

    2016-01-01

    Wake effects cause wind turbine generators (WTGs) within a wind power plant (WPP) to produce different levels of active power and subsequent reactive power capabilities. Further, the impedance between a WTG and the point of interconnection (POI)-which depends on the distance between them-impacts the WPP's reactive power injection capability at the POI. This paper proposes a voltage control scheme for a WPP based on the available reactive current of the doubly-fed induction generators (DFIGs) and its impacts on the POI to improve the reactive power injection capability of the WPP. In this paper, a design strategy for modifying the gainmore » of DFIG controller is suggested and the comprehensive properties of these control gains are investigated. In the proposed scheme, the WPP controller, which operates in a voltage control mode, sends the command signal to the DFIGs based on the voltage difference at the POI. The DFIG controllers, which operate in a voltage control mode, employ a proportional controller with a limiter. The gain of the proportional controller is adjusted depending on the available reactive current of the DFIG and the series impedance between the DFIG and the POI. The performance of the proposed scheme is validated for various disturbances such as a reactive load connection and grid fault using an EMTP-RV simulator. Furthermore, simulation results demonstrate that the proposed scheme promptly recovers the POI voltage by injecting more reactive power after a disturbance than the conventional scheme.« less

  4. Structure and reactivity of chemisorbed species and reaction intermediates: Progress report, December 1, 1984--November 30, 1985

    SciTech Connect (OSTI)

    Madey, T.E.; Kelley, R.D.

    1985-08-01

    The areas of work have supported a common theme: the structure and reactivity of chemisorbed species and reaction intermediate of importance to catalysis. A variety of tools have been to study the structure and chemistry of surface species, and to develop models and concepts of broad utility in chemisorption and catalysis. Adsorption of carbon monoxide, ammonia, hydrogen, and sulfur are discussed. Results of the research conducted or completed in the last year, as well as plans for the coming year, are summarized in this report. The results will be presented in three sections: (a) Surface Molecular Structure and Reactivity as Studied Using Electron Simulated Desorption Ion Angular Distribution (ESDIAD) and High Resolution Electron Energy Loss Spectroscopy (HREELS); (b) Neutron Inelastic Scattering Studies of Adsorption and Reaction on Catalysts; and (c) Reaction Kinetics at High Pressures over Single Crystal Catalysts.

  5. Reactive amendment saltstone (RAS). A novel approach for improved sorption/retention of radionuclides such as technetium and iodine

    SciTech Connect (OSTI)

    Dixon, K. L.; Knox, A. S.; Cozzi, A. D.; Flach, G. P.; Hill, K. A.

    2015-09-30

    This study examined the use of reactive amendments (hydroxyapatite, activated carbon, and two types of organoclays) that prior research suggests may improve retention of 99Tc and 129I. Tests were conducted using surrogates for 99Tc (NaReO4) and 129I (NaI). Results showed that adding up to 10% of organoclay improved the retention of Re without adversely impacting hydraulic properties. To a lesser extent, iodine retention was also improved by adding up to 10% organoclay. Numerical modeling showed that using organoclay as a reactive barrier may significantly retard 99Tc release from saltstone disposal units.

  6. Multi-Objective Advanced Inverter Controls to Dispatch the Real and Reactive Power of Many Distributed PV Systems.

    SciTech Connect (OSTI)

    Reno, Matthew J.; Lave, Matthew Samuel; Broderick, Robert Joseph; Seuss, John; Grijalva, Santiago

    2016-01-01

    The research presented in this report compares several real - time control strategies for the power output of a large number of PV distributed throughout a large distribution feeder circuit. Both real and reactive power controls are considered with the goal of minimizing network over - voltage violations caused by large amounts of PV generation. Several control strategies are considered under various assumptions regarding the existence and latency of a communication network. The control parameters are adjusted to maximize the effectiveness of each control. The controls are then compared based on their ability to achieve multiple objectiv es. These objectives include minimizing the total number of voltage violations , minimizing the total amount of PV energy curtailed or reactive power generated, and maximizing the fairness of any control action among all PV systems . The controls are simulat ed on the OpenDSS platform using time series load and spatially - distributed irradiance data.

  7. Impact of the control rod consumption on the reactivity control of a SFR break-even core

    SciTech Connect (OSTI)

    Blanchet, D.; Fontaine, B.

    2012-07-01

    Current design studies on Sodium Fast Reactor (SFR) differ from those performed in the past by the fact that design criteria are now those of the Generation IV reactors. In order to improve their safety, reactors with break-even cores are preferred because they minimize the needs in terms of reactivity control and limit the consequences of control rod withdrawal. Furthermore, as the reactivity control needs are low, break-even core enables the use of absorbing materials with reduced efficiency (natural boron, hafnium...). Nevertheless, the use of control rods with few absorbing materials may present the disadvantage of a non-negligible ({approx}10%) loss of efficiency due to their consumption under irradiation. This paper presents a methodology to calculate accurately and analyze this consumption. (authors)

  8. Determination of reactive oxygen species from ZnO micro-nano structures with shape-dependent photocatalytic activity

    SciTech Connect (OSTI)

    He, Weiwei; Zhao, Hongxiao; Jia, Huimin; Yin, Jun-Jie; Zheng, Zhi

    2014-05-01

    Graphical abstract: ZnO micro/nano structures with shape dependent photocatalytic activity were prepared by hydrothermal reaction. The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were identified precisely by electron spin resonance spectroscopy. The type of reactive oxygen species was determined by band gap structure of ZnO. - Highlights: • ZnO micro/nano structures with different morphologies were prepared by solvothermal reaction. • Multi-pod like ZnO structures exhibited superior photocatalytic activity. • The generations of hydroxyl radical, superoxide and singlet oxygen from irradiated ZnO were characterized precisely by electron spin resonance spectroscopy. • The type of reactive oxygen species was determined by band gap structure of ZnO. - Abstract: ZnO micro/nano structures with different morphologies have been prepared by the changing solvents used during their synthesis by solvothermal reaction. Three typical shapes of ZnO structures including hexagonal, bell bottom like and multi-pod formed and were characterized by scanning electron microscopy and X-ray diffraction. Multi pod like ZnO structures exhibited the highest photocatalytic activity toward degradation of methyl orange. Using electron spin resonance spectroscopy coupled with spin trapping techniques, we demonstrate an effective way to identify precisely the generation of hydroxyl radicals, superoxide and singlet oxygen from the irradiated ZnO multi pod structures. The type of reactive oxygen species formed was predictable from the band gap structure of ZnO. These results indicate that the shape of micro-nano structures significantly affects the photocatalytic activity of ZnO, and demonstrate the value of electron spin resonance spectroscopy for characterizing the type of reactive oxygen species formed during photoexcitation of semiconductors.

  9. Reactivation of AKT signaling following treatment of cancer cells with PI3K inhibitors attenuates their antitumor effects

    SciTech Connect (OSTI)

    Dufour, Marc; Dormond-Meuwly, Anne; Pythoud, Catherine; Demartines, Nicolas; Dormond, Olivier

    2013-08-16

    Highlights: •PI3K inhibitors inhibit AKT only transiently. •Re-activation of AKT limits the anti-cancer effect of PI3K inhibitors. •The results suggest to combine PI3K and AKT inhibitors in cancer therapy. -- Abstract: Targeting the phosphatidylinositol-3-kinase (PI3K) is a promising approach in cancer therapy. In particular, PI3K blockade leads to the inhibition of AKT, a major downstream effector responsible for the oncogenic activity of PI3K. However, we report here that small molecule inhibitors of PI3K only transiently block AKT signaling. Indeed, treatment of cancer cells with PI3K inhibitors results in a rapid inhibition of AKT phosphorylation and signaling which is followed by the reactivation of AKT signaling after 48 h as observed by Western blot. Reactivation of AKT signaling occurs despite effective inhibition of PI3K activity by PI3K inhibitors. In addition, wortmannin, a broad range PI3K inhibitor, did not block AKT reactivation suggesting that AKT signals independently of PI3K. In a therapeutical perspective, combining AKT and PI3K inhibitors exhibit stronger anti-proliferative and pro-apoptotic effects compared to AKT or PI3K inhibitors alone. Similarly, in a tumor xenograft mouse model, concomitant PI3K and AKT blockade results in stronger anti-cancer activity compared with either blockade alone. This study shows that PI3K inhibitors only transiently inhibit AKT which limits their antitumor activities. It also provides the proof of concept to combine PI3K inhibitors with AKT inhibitors in cancer therapy.

  10. Tin removal from extreme ultraviolet collector optics by inductively coupled plasma reactive ion etching

    SciTech Connect (OSTI)

    Shin, H.; Srivastava, S. N.; Ruzic, D. N. [Center for Plasma Material Interactions, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2008-05-15

    Tin (Sn) has the advantage of delivering higher conversion efficiency compared to other fuel materials (e.g., Xe or Li) in an extreme ultraviolet (EUV) source, a necessary component for the leading next generation lithography. However, the use of a condensable fuel in a lithography system leads to some additional challenges for maintaining a satisfactory lifetime of the collector optics. A critical issue leading to decreased mirror lifetime is the buildup of debris on the surface of the primary mirror that comes from the use of Sn in either gas discharge produced plasma (GDPP) or laser produced plasma (LPP). This leads to a decreased reflectivity from the added material thickness and increased surface roughness that contributes to scattering. Inductively coupled plasma reactive ion etching with halide ions is one potential solution to this problem. This article presents results for etch rate and selectivity of Sn over SiO{sub 2} and Ru. The Sn etch rate in a chlorine plasma is found to be much higher (of the order of hundreds of nm/min) than the etch rate of other materials. A thermally evaporated Sn on Ru sample was prepared and cleaned using an inductively coupled plasma etching method. Cleaning was confirmed using several material characterization techniques. Furthermore, a collector mock-up shell was then constructed and etching was performed on Sn samples prepared in a Sn EUV source using an optimized etching recipe. The sample surface before and after cleaning was analyzed by atomic force microscopy, x-ray photoelectron spectroscopy, and Auger electron spectroscopy. The results show the dependence of etch rate on the location of Sn samples placed on the collector mock-up shell.

  11. Influence of Al/CuO reactive multilayer films additives on exploding foil initiator

    SciTech Connect (OSTI)

    Zhou Xiang; Shen Ruiqi; Ye Yinghua; Zhu Peng; Hu Yan; Wu Lizhi

    2011-11-01

    An investigation on the influence of Al/CuO reactive multilayer films (RMFs) additives on exploding foil initiator was performed in this paper. Cu film and Cu/Al/CuO RMFs were produced by using standard microsystem technology and RF magnetron sputtering technology, respectively. Scanning electron microscopy characterization revealed the distinct layer structure of the as-deposited Al/CuO RMFs. Differential scanning calorimetry was employed to ascertain the amount of heat released in the thermite reaction between Al films and CuO films, which was found to be 2024 J/g. Electrical explosion tests showed that 600 V was the most matching voltage for our set of apparatus. The explosion process of two types of films was observed by high speed camera and revealed that compared with Cu film, an extra distinct combustion phenomenon was detected with large numbers of product particles fiercely ejected to a distance of about six millimeters for Cu/Al/CuO RMFs. By using the atomic emission spectroscopy double line technique, the reaction temperature was determined to be about 6000-7000 K and 8000-9000 K for Cu film and Cu/Al/CuO RMFs, respectively. The piezoelectricity of polyvinylidene fluoride film was employed to measure the average velocity of the slapper accelerated by the explosion of the films. The average velocities of the slappers were calculated to be 381 m/s and 326 m/s for Cu film and Cu/Al/CuO RMFs, respectively, and some probable reasons were discussed with a few suggestions put forward for further work.

  12. Reactive sputter deposition of pyrite structure transition metal disulfide thin films: Microstructure, transport, and magnetism

    SciTech Connect (OSTI)

    Baruth, A.; Manno, M.; Narasimhan, D.; Shankar, A.; Zhang, X.; Johnson, M.; Aydil, E. S.; Leighton, C. [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2012-09-01

    Transition metal disulfides crystallizing in the pyrite structure (e.g., TMS{sub 2}, with TM = Fe, Co, Ni, and Cu) are a class of materials that display a remarkably diverse array of functional properties. These properties include highly spin-polarized ferromagnetism (in Co{sub 1-x}Fe{sub x}S{sub 2}), superconductivity (in CuS{sub 2}), an antiferromagnetic Mott insulating ground state (in NiS{sub 2}), and semiconduction with close to optimal parameters for solar absorber applications (in FeS{sub 2}). Exploitation of these properties in heterostructured devices requires the development of reliable and reproducible methods for the deposition of high quality pyrite structure thin films. In this manuscript, we report on the suitability of reactive sputter deposition from metallic targets in an Ar/H{sub 2}S environment as a method to achieve exactly this. Optimization of deposition temperature, Ar/H{sub 2}S pressure ratio, and total working gas pressure, assisted by plasma optical emission spectroscopy, reveals significant windows over which deposition of single-phase, polycrystalline, low roughness pyrite films can be achieved. This is illustrated for the test cases of the ferromagnetic metal CoS{sub 2} and the diamagnetic semiconductor FeS{sub 2}, for which detailed magnetic and transport characterization are provided. The results indicate significant improvements over alternative deposition techniques such as ex situ sulfidation of metal films, opening up exciting possibilities for all-sulfide heterostructured devices. In particular, in the FeS{sub 2} case it is suggested that fine-tuning of the sputtering conditions provides a potential means to manipulate doping levels and conduction mechanisms, critical issues in solar cell applications. Parenthetically, we note that conditions for synthesis of phase-pure monosulfides and thiospinels are also identified.

  13. Reactivity of liquid and semisolid secondary organic carbon with chloride and nitrate in atmospheric aerosols

    SciTech Connect (OSTI)

    Wang, Bingbing; O'Brien, Rachel E.; Kelly, Stephen T.; Shilling, John E.; Moffet, Ryan C.; Gilles, Mary K.; Laskin, Alexander

    2015-05-14

    Constituents of secondary organic carbon (SOC) in atmospheric aerosols are often mixed with inorganic components and compose a significant mass fraction of fine particulate matter in the atmosphere. Interactions between SOC and other condensed-phase species are not well understood. Here, we investigate the reactions of liquid-like and semi-solid SOC from ozonolysis of limonene (LSOC) and ?-pinene (PSOC) with NaCl using a set of complementary micro-spectroscopic analyses. These reactions result in chloride depletion in the condensed phase, release of gaseous HCl, and formation of organic salts. The reactions attributed to acid displacement by SOC acidic components are driven by the high volatility of HCl. Similar reactions can take place in SOC/NaNO? particles. The results show that an increase in SOC mass fraction in the internally mixed SOC/NaCl particles leads to higher chloride depletion. Glass transition temperatures and viscosity of PSOC were estimated for atmospherically relevant conditions. Data show that the reaction extent depends on SOC composition, particle phase state and viscosity, mixing state, temperature, relative humidity (RH), and reaction time. LSOC shows slightly higher potential to deplete chloride than PSOC. Higher particle viscosity at low temperatures and RH can hinder these acid displacement reactions. Formation of organic salts from these overlooked reactions can alter particle physiochemical properties and may affect their reactivity and ability to act as cloud condensation and ice nuclei. The release and potential recycling of HCl and HNO? from reacted aerosol particles may have important implications for atmospheric chemistry.

  14. IGF-I enhances cellular senescence via the reactive oxygen species-p53 pathway

    SciTech Connect (OSTI)

    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro; Takahashi, Yutaka

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Cellular senescence plays an important role in tumorigenesis and aging process. Black-Right-Pointing-Pointer We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. Black-Right-Pointing-Pointer IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. Black-Right-Pointing-Pointer These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated {beta}-galactosidase (SA-{beta}-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, {gamma}H2AX, the increased levels of p53 and p21 proteins, and activated SA-{beta}-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-{beta}-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  15. Thermal conductivity of nitride films of Ti, Cr, and W deposited by reactive magnetron sputtering

    SciTech Connect (OSTI)

    Jagannadham, Kasichainula

    2015-05-15

    Nitride films of Ti, Cr, and W were deposited using reactive magnetron sputtering from metal targets in argon and nitrogen plasma. TiN films with (200) orientation were achieved on silicon (100) at the substrate temperature of 500 and 600?°C. The films were polycrystalline at lower temperature. An amorphous interface layer was observed between the TiN film and Si wafer deposited at 600?°C. TiN film deposited at 600?°C showed the nitrogen to Ti ratio to be near unity, but films deposited at lower temperature were nitrogen deficient. CrN film with (200) orientation and good stoichiometry was achieved at 600?°C on Si(111) wafer but the film deposited at 500?°C showed cubic CrN and hexagonal Cr{sub 2}N phases with smaller grain size and amorphous back ground in the x-ray diffraction pattern. An amorphous interface layer was not observed in the cubic CrN film on Si(111) deposited at 600?°C. Nitride film of tungsten deposited at 600?°C on Si(100) wafer was nitrogen deficient, contained both cubic W{sub 2}N and hexagonal WN phases with smaller grain size. Nitride films of tungsten deposited at 500?°C were nonstoichiometric and contained cubic W{sub 2}N and unreacted W phases. There was no amorphous phase formed along the interface for the tungsten nitride film deposited at 600?°C on the Si wafer. Thermal conductivity and interface thermal conductance of all the nitride films of Ti, Cr, and W were determined by transient thermoreflectance technique. The thermal conductivity of the films as function of deposition temperature, microstructure, nitrogen stoichiometry and amorphous interaction layer at the interface was determined. Tungsten nitride film containing both cubic and hexagonal phases was found to exhibit much higher thermal conductivity and interface thermal conductance. The amorphous interface layer was found to reduce effective thermal conductivity of TiN and CrN films.

  16. The 'virtual density' principle of neutronics: Toward rapid computation of reactivity effects in practical core distortion scenarios

    SciTech Connect (OSTI)

    Reed, M.; Smith, K.; Forget, B.

    2013-07-01

    Fast reactor core reactivities are sensitive to geometric distortions arising from three distinct phenomena: (1) irradiation swelling of fuel throughout core lifetime, (2) thermal expansion of fuel during transients, and (3) mechanical oscillations during seismic events. Performing comprehensive reactivity analysis of these distortions requires methods for rapidly computing a multitude of minute reactivity changes. Thus, we introduce the 'virtual density' principle of neutronics as a new perturbation technique to achieve this rapid computation. This new method obviates many of the most challenging aspects of conventional geometric perturbation theory. Essentially, this 'virtual density' principle converts geometric perturbations into equivalent material density perturbations (either isotropic or anisotropic), which are highly accurate and comparatively simple to evaluate. While traditional boundary perturbation theory employs surface integrals, the 'virtual density' principle employs equivalent volume integrals. We introduce and validate this method in three subsequent stages: (1) isotropic 'virtual density', (2) anisotropic 'virtual density' for whole cores, and (3) anisotropic 'virtual density' for interior zones within cores. We numerically demonstrate its accuracy for 2-D core flowering scenarios. (authors)

  17. Effects of gasoline reactivity and ethanol content on boosted premixed and partially stratified low-temperature gasoline combustion (LTGC)

    SciTech Connect (OSTI)

    Dec, John E.; Yang, Yi; Ji, Chunsheng; Dernotte, Jeremie

    2015-04-14

    Low-temperature gasoline combustion (LTGC), based on the compression ignition of a premixed or partially premixed dilute charge, can provide thermal efficiencies (TE) and maximum loads comparable to those of turbo-charged diesel engines, and ultra-low NOx and particulate emissions. Intake boosting is key to achieving high loads with dilute combustion, and it also enhances the fuel's autoignition reactivity, reducing the required intake heating or hot residuals. These effects have the advantages of increasing TE and charge density, allowing greater timing retard with good stability, and making the fuel ?- sensitive so that partial fuel stratification (PFS) can be applied for higher loads and further TE improvements. However, at high boost the autoignition reactivity enhancement can become excessive, and substantial amounts of EGR are required to prevent overly advanced combustion. Accordingly, an experimental investigation has been conducted to determine how the tradeoff between the effects of intake boost varies with fuel-type and its impact on load range and TE. Five fuels are investigated: a conventional AKI=87 petroleum-based gasoline (E0), and blends of 10 and 20% ethanol with this gasoline to reduce its reactivity enhancement with boost (E10 and E20). Furthermore, a second zero-ethanol gasoline with AKI=93 (matching that of E20) was also investigated (CF-E0), and some neat ethanol data are also reported.

  18. Effect of a detailed radial core expansion reactivity feedback model on ATWS calculations using SASSYS/SAS4A

    SciTech Connect (OSTI)

    Wigeland, R.A.

    1986-01-01

    The present emphasis on inherent safety and inherently safe designs for liquid-metal reactors has resulted in a need to represent the various reactivity feedback mechanisms as accurately as possible. In particular, the reactivity feedback from radial core expansion has been found to provide the dominant negative feedback contribution in postulated anticipated transient without scram (ATWS) events. Review of the existing modeling in the SASSYS/SAS4A computer code system revealed that while the modeling may be adequate for the early phases of various unprotected transients, the accuracy would be less than desirable for the extended transients which typically occur for inherently safe designs. The existing model for calculating the reactivity feedback from radial core expansion uses a feedback from radial core expansion uses a feedback coefficient in conjunction with changes in the temperatures of the grid support plate and the above-core load pad. The accuracy of this approach is determined partly by the conditions used in deriving the feedback coefficient, and their relevance to the transient being investigated. Accuracy is also affected by the need to include effects other than those that could be directly related to changes in the grid plate and above-core load pad temperatures, such as subassembly bowing and the potential for clearances to occur between subassemblies in the above-core load pad region. As a result, a detailed model was developed in an attempt to account for these and other effects in a more mechanistic form.

  19. Effects of gasoline reactivity and ethanol content on boosted premixed and partially stratified low-temperature gasoline combustion (LTGC)

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

    Dec, John E.; Yang, Yi; Ji, Chunsheng; Dernotte, Jeremie

    2015-04-14

    Low-temperature gasoline combustion (LTGC), based on the compression ignition of a premixed or partially premixed dilute charge, can provide thermal efficiencies (TE) and maximum loads comparable to those of turbo-charged diesel engines, and ultra-low NOx and particulate emissions. Intake boosting is key to achieving high loads with dilute combustion, and it also enhances the fuel's autoignition reactivity, reducing the required intake heating or hot residuals. These effects have the advantages of increasing TE and charge density, allowing greater timing retard with good stability, and making the fuel Φ- sensitive so that partial fuel stratification (PFS) can be applied for highermore » loads and further TE improvements. However, at high boost the autoignition reactivity enhancement can become excessive, and substantial amounts of EGR are required to prevent overly advanced combustion. Accordingly, an experimental investigation has been conducted to determine how the tradeoff between the effects of intake boost varies with fuel-type and its impact on load range and TE. Five fuels are investigated: a conventional AKI=87 petroleum-based gasoline (E0), and blends of 10 and 20% ethanol with this gasoline to reduce its reactivity enhancement with boost (E10 and E20). Furthermore, a second zero-ethanol gasoline with AKI=93 (matching that of E20) was also investigated (CF-E0), and some neat ethanol data are also reported.« less

  20. Influence of cluster–support interactions on reactivity of size-selected NbxOy clusters

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

    Nakayama, Miki; Xue, Meng; An, Wei; Liu, Ping; White, Michael G.

    2015-04-17

    Size-selected niobium oxide nanoclusters (Nb3O5, Nb3O7, Nb4O7, and Nb4O10) were deposited at room temperature onto a Cu(111) surface and a thin film of Cu2O on Cu(111), and their interfacial electronic interactions and reactivity toward water dissociation were examined. These clusters were specifically chosen to elucidate the effects of the oxidation state of the metal centers; Nb3O5 and Nb4O7 are the reduced counterparts of Nb3O7 and Nb4O10, respectively. From two-photon photoemission spectroscopy (2PPE) measurements, we found that the work function increases upon cluster adsorption in all cases, indicating a negative interfacial dipole moment with the positive end pointing into the surface.more » The amount of increase was greater for the clusters with more metal centers and higher oxidation state. Additional analysis with DFT calculations of the clusters on Cu(111) indicated that the reduced clusters donate electrons to the substrate, indicating that the intrinsic cluster dipole moment makes a larger contribution to the overall interfacial dipole moment than charge transfer. X-ray photoelectron spectroscopy (XPS) measurements showed that the Nb atoms of Nb3O7 and Nb4O10 are primarily Nb5+ on Cu(111), while for the reduced Nb3O5 and Nb4O7 clusters, a mixture of oxidation states was observed on Cu(111). Temperature-programmed desorption (TPD) experiments with D2O showed that water dissociation occurred on all systems except for the oxidized Nb3O7 and Nb4O10 clusters on the Cu2O film. A comparison of our XPS and TPD results suggests that Nb5+ cations associated with Nb=O terminal groups act as Lewis acid sites which are key for water binding and subsequent dissociation. TPD measurements of 2-propanol dehydration also show that the clusters active toward water dissociation are indeed acidic. DFT calculations of water dissociation on Nb3O7 support our TPD results, but the use of bulk Cu2O(111) as a model for the Cu2O film merits future scrutiny in terms of interfacial charge transfer. The combination of our experimental and theoretical results suggests that both Lewis acidity and metal reducibility are important for water dissociation.« less

  1. Tuning the reactivity of mononuclear nonheme manganese(iv)-oxo complexes by triflic acid

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

    Chen, Junying; Yoon, Heejung; Lee, Yong -Min; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2015-04-14

    Triflic acid (HOTf)-bound nonheme Mn(IV)-oxo complexes, [(L)MnIV(O)]2+–(HOTf)2 (L = N4Py and Bn-TPEN; N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine and Bn-TPEN = N-benzyl-N,N',N'-tris(2-pyridylmethyl)ethane-1,2-diamine), were synthesized by adding HOTf to the solutions of the [(L)MnIV(O)]2+ complexes and were characterized by various spectroscopies. The one-electron reduction potentials of the MnIV(O) complexes exhibited a significant positive shift upon binding of HOTf. The driving force dependences of electron transfer (ET) from electron donors to the MnIV(O) and MnIV(O)–(HOTf)2 complexes were examined and evaluated in light of the Marcus theory of ET to determine the reorganization energies of ET. The smaller reorganization energies and much more positive reduction potentialsmore » of the [(L)MnIV(O)]2+–(HOTf)2 complexes resulted in greatly enhanced oxidation capacity towards one-electron reductants and para-X-substituted-thioanisoles. The reactivities of the Mn(IV)-oxo complexes were markedly enhanced by binding of HOTf, such as a 6.4 × 105-fold increase in the oxygen atom transfer (OAT) reaction (i.e., sulfoxidation). Such a remarkable acceleration in the OAT reaction results from the enhancement of ET from para-X-substituted-thioanisoles to the MnIV(O) complexes as revealed by the unified ET driving force dependence of the rate constants of OAT and ET reactions of [(L)MnIV(O)]2+–(HOTf)2. In contrast, deceleration was observed in the rate of H-atom transfer (HAT) reaction of [(L)MnIV(O)]2+–(HOTf)2 complexes with 1,4-cyclohexadiene as compared with those of the [(L)MnIV(O)]2+ complexes. Thus, the binding of two HOTf molecules to the MnIV(O) moiety resulted in remarkable acceleration of the ET rate when the ET is thermodynamically feasible. When the ET reaction is highly endergonic, the rate of the HAT reaction is decelerated due to the steric effect of the counter anion of HOTf.« less

  2. Tuning the reactivity of mononuclear nonheme manganese(iv)-oxo complexes by triflic acid

    SciTech Connect (OSTI)

    Chen, Junying; Yoon, Heejung; Lee, Yong -Min; Seo, Mi Sook; Sarangi, Ritimukta; Fukuzumi, Shunichi; Nam, Wonwoo

    2015-04-14

    Triflic acid (HOTf)-bound nonheme Mn(IV)-oxo complexes, [(L)MnIV(O)]2+–(HOTf)2 (L = N4Py and Bn-TPEN; N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine and Bn-TPEN = N-benzyl-N,N',N'-tris(2-pyridylmethyl)ethane-1,2-diamine), were synthesized by adding HOTf to the solutions of the [(L)MnIV(O)]2+ complexes and were characterized by various spectroscopies. The one-electron reduction potentials of the MnIV(O) complexes exhibited a significant positive shift upon binding of HOTf. The driving force dependences of electron transfer (ET) from electron donors to the MnIV(O) and MnIV(O)–(HOTf)2 complexes were examined and evaluated in light of the Marcus theory of ET to determine the reorganization energies of ET. The smaller reorganization energies and much more positive reduction potentials of the [(L)MnIV(O)]2+–(HOTf)2 complexes resulted in greatly enhanced oxidation capacity towards one-electron reductants and para-X-substituted-thioanisoles. The reactivities of the Mn(IV)-oxo complexes were markedly enhanced by binding of HOTf, such as a 6.4 × 105-fold increase in the oxygen atom transfer (OAT) reaction (i.e., sulfoxidation). Such a remarkable acceleration in the OAT reaction results from the enhancement of ET from para-X-substituted-thioanisoles to the MnIV(O) complexes as revealed by the unified ET driving force dependence of the rate constants of OAT and ET reactions of [(L)MnIV(O)]2+–(HOTf)2. In contrast, deceleration was observed in the rate of H-atom transfer (HAT) reaction of [(L)MnIV(O)]2+–(HOTf)2 complexes with 1,4-cyclohexadiene as compared with those of the [(L)MnIV(O)]2+ complexes. Thus, the binding of two HOTf molecules to the MnIV(O) moiety resulted in remarkable acceleration of the ET rate when the ET is thermodynamically feasible. When the ET reaction is highly endergonic, the rate of the HAT reaction is decelerated due to the steric effect of the counter anion of HOTf.

  3. Cationic Gold Clusters Ligated with Differently Substituted Phosphines: Effect of Substitution on Ligand Reactivity and Binding

    SciTech Connect (OSTI)

    Johnson, Grant E.; Olivares, Astrid M.; Hill, David E.; Laskin, Julia

    2015-01-01

    We present a systematic study of the effect of the number of methyl (Me) and cyclohexyl (Cy) functional groups in monodentate phosphine ligands on the solution-phase synthesis of ligated sub-nanometer gold clusters and their gas-phase fragmentation pathways. Small mixed ligand cationic gold clusters were synthesized using ligand exchange reactions between pre-formed triphenylphosphine ligated (PPh3) gold clusters and monodentate Me- and Cy-substituted ligands in solution and characterized using electrospray ionization mass spectrometry (ESI-MS) and collision-induced dissociation (CID) experiments. Under the same experimental conditions, larger gold-PPh3 clusters undergo efficient exchange of unsubstituted PPh3 ligands for singly Me- and Cy-substituted PPh2Me and PPh2Cy ligands. The efficiency of ligand exchange decreases with an increasing number of Me or Cy groups in the substituted phosphine ligands. CID experiments performed for a series of ligand-exchanged gold clusters indicate that loss of a neutral Me-substituted ligand is preferred over loss of a neutral PPh¬3 ligand while the opposite trend is observed for Cy-substituted ligands. The branching ratio of the competing ligand loss channels is strongly correlated with the electron donating ability of the phosphorous lone pair as determined by the relative proton affinity of the ligand. The results indicate that the relative ligand binding energies increase in the order PMe3 < PPhMe2 < PPh2Me < PPh3< PPh2Cy < PPhCy2< PCy3. Furthermore, the difference in relative ligand binding energies increases with the number of substituted PPh3-mMem or PPh3-mCym ligands (L) exchanged onto each cluster. This study provides the first experimental determination of the relative binding energies of ligated gold clusters containing differently substituted monophosphine ligands, which are important to controlling their synthesis and reactivity in solution. The results also indicate that ligand substitution is an important parameter that must be considered in theoretical modeling of these complex systems

  4. STARTUP REACTIVITY ACCOUNTABILITY ATTRIBUTED TO ISOTOPIC TRANSMUTATIONS IN THE IRRADIATED BERYLLIUM REFLECTOR OF THE HIGH FLUX ISTOTOPE REACTOR

    SciTech Connect (OSTI)

    Chandler, David [ORNL] [ORNL; Maldonado, G Ivan [ORNL] [ORNL; Primm, Trent [ORNL] [ORNL

    2010-01-01

    The objective of this study is to develop a methodology to predict the reactivity impact as a function of outage time between cycles of 3He, 6Li, and other poisons in the High Flux Isotope Reactor s (HFIR) beryllium reflector. The reactivity worth at startup of the HFIR has been incorrectly predicted in the past after the reactor has been shut-down for long periods of time. The incorrect prediction was postulated to be due to the erroneous calculation of 3He buildup in the beryllium reflector. It is necessary to develop a better estimate of the start-of-cycle symmetric critical control element positions since if the estimated and actual symmetrical critical control element positions differ by more than $1.55 in reactivity (approximately one-half inch in control element startup position), HFIR is to be shutdown and a technical evaluation is performed to resolve the discrepancy prior to restart. 3He is generated and depleted during operation, but during an outage, the depletion of 3He ceases because it is a stable isotope. 3He is born from the radioactive decay of tritium, and thus the concentration of 3He increases during shutdown. The computer program SCALE, specifically the TRITON and CSAS5 control modules including the KENO V.A, COUPLE, and ORIGEN functional modules were utilized in this study. An equation relating the down time (td) to the change in symmetric control element position was generated and validated against measurements for approximately 40 HFIR operating cycles. The newly-derived correlation was shown to improve accuracy of predictions for long periods of down time.

  5. Study of Inhibition, Reactivation and Aging Processes of Pesticides Using Graphene Nanosheets/Gold Nanoparticles-Based Acetylcholinesterase Biosensor

    SciTech Connect (OSTI)

    Zhang, Lin; Long, Linjuan; Zhang, Weiying; Du, Dan; Lin, Yuehe

    2012-09-10

    Organophosphate (OP) and carbamate pesticides exert their toxicity via attacking the hydroxyl moiety of serine in the 'active site' of acetylcholinesterase (AChE). In this paper we developed a stable AChE biosensor based on self-assembling AChE to graphene nanosheet (GN)-gold nanoparticles (AuNPs) nanocomposite electrode for investigation of inhibition, reactivation and aging processes of different pesticides. It is confirmed that pesticides can inhibit AChE in a short time. OPs poisoning is treatable with oximes while carbarmates exposure is insensitive to oximes. The proposed electrochemical approach thus provides a new simple tool for comparison of pesticide sensitivity and guide of therapeutic intervention.

  6. Quantifying and Addressing the DOE Material Reactivity Requirements with Analysis and Testing of Hydrogen Storage Materials & Systems

    SciTech Connect (OSTI)

    Khalil, Y. F

    2015-01-05

    The objective of this project is to examine safety aspects of candidate hydrogen storage materials and systems being developed in the DOE Hydrogen Program. As a result of this effort, the general DOE safety target will be given useful meaning by establishing a link between the characteristics of new storage materials and the satisfaction of safety criteria. This will be accomplished through the development and application of formal risk analysis methods, standardized materials testing, chemical reactivity characterization, novel risk mitigation approaches and subscale system demonstration. The project also will collaborate with other DOE and international activities in materials based hydrogen storage safety to provide a larger, highly coordinated effort.

  7. Modelling of multiphase flow in ironmaking blast furnace

    SciTech Connect (OSTI)

    Dong, X.F.; Yu, A.B.; Burgess, J.M.; Pinson, D.; Chew, S.; Zulli, P.

    2009-01-15

    A mathematical model for the four-phase (gas, powder, liquid, and solids) flow in a two-dimensional ironmaking blast furnace is presented by extending the existing two-fluid flow models. The model describes the motion of gas, solid, and powder phases, based on the continuum approach, and implements the so-called force balance model for the flow of liquids, such as metal and slag in a blast furnace. The model results demonstrate a solid stagnant zone and dense powder hold-up region, as well as a dense liquid flow region that exists in the lower part of a blast furnace, which are consistent with the experimental observations reported in the literature. The simulation is extended to investigate the effects of packing properties and operational conditions on the flow and the volume fraction distribution of each phase in a blast furnace. It is found that solid movement has a significant effect on powder holdup distribution. Small solid particles and low porosity distribution are predicted to affect the fluid flow considerably, and this can cause deterioration in bed permeability. The dynamic powder holdup in a furnace increases significantly with the increase of powder diameter. The findings should be useful to better understand and control blast furnace operations.

  8. Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry

    DOE Patents [OSTI]

    Sinha, Dipen N.

    2003-11-11

    An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.

  9. Noninvasive Characterization Of A Flowing Multiphase Fluid Using Ultrasonic Interferometry

    DOE Patents [OSTI]

    Sinha, Dipen N. (Los Alamos, NM)

    2005-05-10

    An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.

  10. Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry

    DOE Patents [OSTI]

    Sinha, Dipen N. (Los Alamos, NM)

    2007-06-12

    An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.

  11. Cryogenic homogenization and sampling of heterogeneous multi-phase feedstock

    DOE Patents [OSTI]

    Doyle, Glenn Michael (Lakewood, CO); Ideker, Virgene Linda (Arvada, CO); Siegwarth, James David (Boulder, CO)

    2002-01-01

    An apparatus and process for producing a homogeneous analytical sample from a heterogenous feedstock by: providing the mixed feedstock, reducing the temperature of the feedstock to a temperature below a critical temperature, reducing the size of the feedstock components, blending the reduced size feedstock to form a homogeneous mixture; and obtaining a representative sample of the homogeneous mixture. The size reduction and blending steps are performed at temperatures below the critical temperature in order to retain organic compounds in the form of solvents, oils, or liquids that may be adsorbed onto or absorbed into the solid components of the mixture, while also improving the efficiency of the size reduction. Preferably, the critical temperature is less than 77 K (-196.degree. C.). Further, with the process of this invention the representative sample may be maintained below the critical temperature until being analyzed.

  12. Fibrous ceramic monoliths made from multi-phase ceramic filaments

    DOE Patents [OSTI]

    Goretta, Kenneth C.; Singh, Dileep; Polzin, Bryant J.; Cruse, Terry; Picciolo, John J.

    2008-11-18

    A method for producing composite ceramic material is provided wherein a core ceramic structure is produced and simultaneously enveloped with a sleeve of similar material.

  13. Hybrid Rotor Compression for Multiphase and Liquids-Rich Wellhead

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

    but also allows for compression of wet gas, or gas that contains liquid content. At many natural gas wellheads, liquids-typically heavier hydrocarbons and water-are present in the...

  14. Thermodynamic approach to the stability of multi-phase systems...

    Office of Scientific and Technical Information (OSTI)

    As a result, model development towards more accurate calculations more is discussed. less Authors: Samolyuk, German D. 1 ; Osetskiy, Yury N. 1 + Show Author Affiliations ...

  15. Survival rate of initial azimuthal anisotropy in a multiphase...

    Office of Scientific and Technical Information (OSTI)

    C Additional Journal Information: Journal Volume: 92; Journal Issue: 5; Journal ID: ISSN 0556-2813 Publisher: American Physical Society Sponsoring Org: USDOE Country of...

  16. Characterization and modeling of multiphase mixtures from deep, subsea wells

    SciTech Connect (OSTI)

    Song, S.; Hill, A.D.

    1996-09-01

    The effects of flow in a vertical pipe on the flow in subsequent horizontal pipes were investigated by performing both experimental and theoretical studies. This geometry mimics production from subsea wells connected to subsea horizontal flow lines. The fluids were conducted into a 153-meter deep well through two different casings, allowing the mixtures to flow up through a 5.08 cm ID vertical pipe and then into a horizontal flow loop which consists of two pipes with 6.35 cm ID and 18.4 cm ID, respectively. The flow regime behaviors in the horizontal pipes were studied for a wide range of flow rates. From the tests, it was found that the flow regimes in the small horizontal pipe were greatly affected by the flows in the vertical pipe while the flow regimes in the large horizontal pipe were hardly affected. A theoretical model based on wave mechanics was developed to simulate the process of the liquid slugs formed in the vertical pipe being carried over into the horizontal pipe. The theoretical predictions matched the experimental observations very well. The results of this study will greatly benefit the understanding of the flow regime behavior that will occur in deep, subsea flow lines transporting multiple phases from subsea completions.

  17. Plasmas in Multiphase Media: Bubble Enhanced Discharges in Liquids...

    Office of Scientific and Technical Information (OSTI)

    of atmospheric pressure plasmas in the form of dielectric barrier discharges and plasma jets with organic materials and liquids. We also made advances in our ability to use...

  18. Multiphase Nano-Composite Coatings for Achieving Energy Optimization

    SciTech Connect (OSTI)

    Dr. Jose Nainaparampil

    2012-03-26

    UES Inc. and ANL teamed in this work to develop novel coating systems for the protection of surfaces from thermal degradation mainly in two applications; Machining and Die casting. These coatings were specifically designed for the purpose by incorporating required material phases and the overall architecture, which led to reduce the energy usage and increase efficiency of the operations. Following the UES/ANL'Â?s feasibility work, the coatings were developed utilizing High power impulse magnetron sputtering (HiPMS) and Large area filtered arc deposition (LAFAD) techniques. Toughness, hardness and oxidation resistance: contrasting qualities have been mixed in the right proportion to attain the suitable material characteristic for the cause. Hafnium diboride (HfB2) based materials provided such a system and its properties were tamed to attain the right combination of toughness and hardness by working on the microstructure and architecture of coatings. An effective interfacing material (graded concentrations of topcoat) was also achieved in this work to provide the required adhesion between the substrate and the coating. Combination of an appropriate bond coat and a functional top coat provided the present thermal degradation resistant coating for cutting tools and die-casting applications. Laboratory level performance tests and industrial level application tests by partner companies (Beta Site Testing) were used for the development of these coatings.

  19. Development of Modeling Methods and Tools for Predicting Coupled Reactive Transport Processes in Porous Media at Multiple Scales

    SciTech Connect (OSTI)

    Clement, T Prabhakar; Barnett, Mark O; Zheng, Chunmiao; Jones, Norman L

    2010-05-05

    DE-FG02-06ER64213: Development of Modeling Methods and Tools for Predicting Coupled Reactive Transport Processes in Porous Media at Multiple Scales Investigators: T. Prabhakar Clement (PD/PI) and Mark O. Barnett (Auburn), Chunmiao Zheng (Univ. of Alabama), and Norman L. Jones (BYU). The objective of this project was to develop scalable modeling approaches for predicting the reactive transport of metal contaminants. We studied two contaminants, a radioactive cation [U(VI)] and a metal(loid) oxyanion system [As(III/V)], and investigated their interactions with two types of subsurface materials, iron and manganese oxyhydroxides. We also developed modeling methods for describing the experimental results. Overall, the project supported 25 researchers at three universities. Produced 15 journal articles, 3 book chapters, 6 PhD dissertations and 6 MS theses. Three key journal articles are: 1) Jeppu et al., A scalable surface complexation modeling framework for predicting arsenate adsorption on goethite-coated sands, Environ. Eng. Sci., 27(2): 147-158, 2010. 2) Loganathan et al., Scaling of adsorption reactions: U(VI) experiments and modeling, Applied Geochemistry, 24 (11), 2051-2060, 2009. 3) Phillippi, et al., Theoretical solid/solution ratio effects on adsorption and transport: uranium (VI) and carbonate, Soil Sci. Soci. of America, 71:329-335, 2007

  20. Structure and reactivity of chemisorbed species and reaction intermediates: Progress report, December 1, 1985-November 30, 1986

    SciTech Connect (OSTI)

    Madey, T.E.

    1986-07-01

    The areas of work supported under this contract by DOE during the period 12/1/85-11/30/86 have a common theme: the structure and reactivity of chemisorbed species and reaction intermediates of importance to catalysis. A variety of tools have been used to study the structure and chemistry of surface species, and to develop models and concepts of broad utility in chemisorption and catalysis. Fourteen papers have appeared, are in press, or in preparation in FY86. Results of the research conducted or completed in the last year are summarized in this report. The results are presented in three sections: surface molecular structure and reactivity as studied using electron stimulated desoprtion ion angular distribution (ESDIAD) and high resolution electron energy loss spectroscopy (HREELS); neutron inelastic scattering studies of adsorption and reaction on metal catalysts and zeolite catalysts; reaction kinetics at high pressures over single crystal metal catalysts: mechanisms of catalyst poisoning. A listing of publications during the past year is included.

  1. Real Power and Reactive Power Control of a Three-Phase Single-Stage-PV System and PV voltage Stability

    SciTech Connect (OSTI)

    Li, Huijuan; Xu, Yan; Adhikari, Sarina; Rizy, D Tom; Li, Fangxing; Irminger, Philip

    2012-01-01

    Grid-connected photovoltaic (PV) systems with power electronic interfaces can provide both real and reactive power to meet power system needs with appropriate control algorithms. This paper presents the control algorithm design for a three-phase single-stage grid-connected PV inverter to achieve either maximum power point tracking (MPPT) or a certain amount of real power injection, as well as the voltage/var control. The switching between MPPT control mode and a certain amount of real power control mode is automatic and seamless. Without the DC-to-DC booster stage, PV DC voltage stability is an important issue in the control design especially when the PV inverter is operating at maximum power point (MPP) with voltage/var control. The PV DC voltage collapse phenomenon and its reason are discussed. The method based on dynamic correction of the PV inverter output is proposed to ensure PV DC voltage stability. Simulation results of the single-stage PV system during system disturbances and fast solar irradiation changes confirm that the proposed control algorithm for single-stage PV inverters can provide appropriate real and reactive power services and ensure PV DC voltage stability during dynamic system operation and atmospheric conditions.

  2. Evaporite Caprock Integrity. An experimental study of reactive mineralogy and pore-scale heterogeneity during brine-CO2 exposure

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

    Smith, Megan M.; Sholokhova, Yelena; Hao, Yue; Carroll, Susan A.

    2012-07-25

    Characterization and geochemical data are presented from a core-flooding experiment on a sample from the Three Fingers evaporite unit forming the lower extent of caprock at the Weyburn-Midale reservoir, Canada. This low-permeability sample was characterized in detail using X-ray computed microtomography before and after exposure to CO 2-acidified brine, allowing mineral phase and voidspace distributions to be quantified in three dimensions. Solution chemistry indicated that CO 2-acidified brine preferentially dissolved dolomite until saturation was attained, while anhydrite remained unreactive. Dolomite dissolution contributed to increases in bulk permeability through the formation of a localized channel, guided by microfractures as well asmore » porosity and reactive phase distributions aligned with depositional bedding. An indirect effect of carbonate mineral reactivity with CO 2-acidified solution is voidspace generation through physical transport of anhydrite freed from the rock matrix following dissolution of dolomite. The development of high permeability fast pathways in this experiment highlights the role of carbonate content and potential fracture orientations in evaporite caprock formations considered for both geologic carbon sequestration and CO 2-enhanced oil recovery operations.« less

  3. Gas-Phase Reactions of Doubly Charged Lanthanide Cations with Alkanes and Alkenes. Trends in Metal(2+) Reactivity

    SciTech Connect (OSTI)

    Gibson, John K.; Marcalo, Joaquim; Santos, Marta; Pires de Matos, Antonio; Haire, Richard G.

    2008-12-08

    The gas-phase reactivity of doubly-charged lanthanide cations, Ln2+ (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), with alkanes (methane, ethane, propane, n-butane) and alkenes (ethene, propene, 1-butene) was studied by Fourier transform ion cyclotron resonance mass spectrometry. The reaction products consisted of different combinations of doubly-charged organometallic ions?adducts or species formed via metal-ion-induced hydrogen, dihydrogen, alkyl, or alkane eliminations from the hydrocarbons?and singly-charged ions that resulted from electron, hydride, or methide transfers from the hydrocarbons to the metal ions. The only lanthanide cations capable of activating the hydrocarbons to form doubly-charged organometallic ions were La2+, Ce2+, Gd2+, and Tb2+, which have ground-state or low-lying d1 electronic configurations. Lu2+, with an accessible d1 electronic configuration but a rather high electron affinity, reacted only through transfer channels. The remaining Ln2+ reacted via transfer channels or adduct formation. The different accessibilities of d1 electronic configurations and the range of electron affinities of the Ln2+ cations allowed for a detailed analysis of the trends for metal(2+) reactivity and the conditions for occurrence of bond activation, adduct formation, and electron, hydride, and methide transfers.

  4. Simulating Geologic Co-sequestration of Carbon Dioxide and Hydrogen Sulfide in a Basalt Formation

    SciTech Connect (OSTI)

    Bacon, Diana H.; Ramanathan, Ramya; Schaef, Herbert T.; McGrail, B. Peter

    2014-01-15

    Co-sequestered CO2 with H2S impurities could affect geologic storage, causing changes in pH and oxidation state that affect mineral dissolution and precipitation reactions and the mobility of metals present in the reservoir rocks. We have developed a variable component, non-isothermal simulator, STOMP-COMP (Water, Multiple Components, Salt and Energy), which simulates multiphase flow gas mixtures in deep saline reservoirs, and the resulting reactions with reservoir minerals. We use this simulator to model the co-injection of CO2 and H2S into brecciated basalt flow top. A 1000 metric ton injection of these supercritical fluids, with 99% CO2 and 1% H2S, is sequestered rapidly by solubility and mineral trapping. CO2 is trapped mainly as calcite within a few decades and H2S is trapped as pyrite within several years.

  5. Program for certification of waste from contained firing facility: Establishment of waste as non-reactive and discussion of potential waste generation problems

    SciTech Connect (OSTI)

    Green, L.; Garza, R.; Maienschein, J.; Pruneda, C.

    1997-09-30

    Debris from explosives testing in a shot tank that contains 4 weight percent or less of explosive is shown to be non-reactive under the specified testing protocol in the Code of Federal Regulations. This debris can then be regarded as a non-hazardous waste on the basis of reactivity, when collected and packaged in a specified manner. If it is contaminated with radioactive components (e.g. depleted uranium), it can therefore be disposed of as radioactive waste or mixed waste, as appropriate (note that debris may contain other materials that render it hazardous, such as beryllium). We also discuss potential waste generation issues in contained firing operations that are applicable to the planned new Contained Firing Facility (CFF). The goal of this program is to develop and document conditions under which shot debris from the planned Contained Firing Facility (CFF) can be handled, shipped, and accepted for waste disposal as non-reactive radioactive or mixed waste. This report fulfills the following requirements as established at the outset of the program: 1. Establish through testing the maximum level of explosive that can be in a waste and still have it certified as non-reactive. 2. Develop the procedure to confirm the acceptability of radioactive-contaminated debris as non-reactive waste at radioactive waste disposal sites. 3. Outline potential disposal protocols for different CFF scenarios (e.g. misfires with scattered explosive).

  6. Radiocarbon as a Reactive Tracer for Tracking Permanent CO2 Storage in Basaltic Rocks

    SciTech Connect (OSTI)

    Matter, Juerg; Stute, Martin; Schlosser, Peter; Broecker, Wallace

    2015-09-30

    In view of concerns about the long-term integrity and containment of CO2 storage in geologic reservoirs, many efforts have been made to improve the monitoring, verification and accounting methods for geologically stored CO2. Our project aimed to demonstrate that carbon-14 (14C) could be used as a reactive tracer to monitor geochemical reactions and evaluate the extent of mineral trapping of CO2 in basaltic rocks. The capacity of a storage reservoir for mineral trapping of CO2 is largely a function of host rock composition. Mineral carbonation involves combining CO2 with divalent cations including Ca2+, Mg2+ and Fe2+. The most abundant geological sources for these cations are basaltic rocks. Based on initial storage capacity estimates, we know that basalts have the necessary capacity to store million to billion tons of CO2 via in situ mineral carbonation. However, little is known about CO2-fluid-rock reactions occurring in a basaltic storage reservoir during and post-CO2 injection. None of the common monitoring and verification techniques have been able to provide a surveying tool for mineral trapping. The most direct method for quantitative monitoring and accounting involves the tagging of the injected CO2 with 14C because 14C is not present in deep geologic reservoirs prior to injection. Accordingly, we conducted two CO2 injection tests at the CarbFix pilot injection site in Iceland to study the feasibility of 14C as a reactive tracer for monitoring CO2-fluid-rock reactions and CO2 mineralization. Our newly developed monitoring techniques, using 14C as a reactive tracer, have been successfully demonstrated. For the first time, permanent and safe disposal of CO2 as environmentally benign carbonate minerals in basaltic rocks could be shown. Over 95% of the injected CO2 at the CarbFix pilot injection site was mineralized to carbonate minerals in less than two years after injection. Our monitoring results confirm that CO2 mineralization in basaltic rocks is far faster than previously postulated.

  7. Structure and solid-state reactivity of Sc, Y, and lanthanide complexes of propiolic and tetrolic acid. [gamma radiation

    SciTech Connect (OSTI)

    Brodkin, J.S.

    1990-01-01

    The structure/reactivity relationships for several metal complexes of propynoic and 2-butynoic acid (propiolic and tetrolic acids, referred to as prop and tetr) were studied. Single-crystal X-ray structure determinations were carried out for Sc(prop){sub 3}, Lat(tetr){sub 3}{center dot}2H{sub 2}O, and two pseudo-polymorphs of La propiolate, La(prop){sub 3}{center dot}3H{sub 2}O and La(prop){sub 3}{center dot}3CH{sub 3}OH. The structures were analyzed for the presence of short (< 4.2 {angstrom}) contacts between {alpha} and {beta}{prime} carbon atoms of neighboring acetylenic functional groups. The existence of a continuous series of such contacts in the structure indicates that the compound has potential to undergo a 1,2-addition reaction leading to the formation of a polymeric product. All of the compounds studied were found to be potentially reactive. The propiolate and tetrolate complexes react in the solid state upon exposure to {gamma}-radiation. The radiation-induced reaction products of both La propiolate derivatives were shown by NMR spectral analysis to be branched polymers. The product resulting from the {gamma}-irradiation of Sc(prop){sub 3} was shown to be polymeric also, however, in this case, not branched. When La(tetr){sub 3}{center dot}2H{sub 2}O was exposed to {gamma}-radiation, the resultant product was not polymeric. The relative orientation of the reactive groups was believed to be a factor in determining whether or not branched polymers would be produced. Thermal analysis of the propiolate complexes indicated that solid state polymerization of these compounds can also occur by thermal induction. However, La(tetr){sub 3}{center dot}2H{sub 2}O is more likely to undergo decomposition than solid-state polymerization when heated. This result is probably associated with the presence of a terminal methyl group on the triple bond.

  8. Quantitative assessment of alkali-reactive aggregate mineral content through XRD using polished sections as a supplementary tool to RILEM AAR-1 (petrographic method)

    SciTech Connect (OSTI)

    Castro, Nelia; Sorensen, Bjorn E.; Broekmans, Maarten A.T.M.

    2012-11-15

    The mineral content of 5 aggregate samples from 4 different countries, including reactive and non-reactive aggregate types, was assessed quantitatively by X-ray diffraction (XRD) using polished sections. Additionally, electron probe microanalyzer (EPMA) mapping and cathodoluminescence (CL) were used to characterize the opal-CT identified in one of the aggregate samples. Critical review of results from polished sections against traditionally powdered specimen has demonstrated that for fine-grained rocks without preferred orientation the assessment of mineral content by XRD using polished sections may represent an advantage over traditional powder specimens. Comparison of data on mineral content and silica speciation with expansion data from PARTNER project confirmed that the presence of opal-CT plays an important role in the reactivity of one of the studied aggregates. Used as a complementary tool to RILEM AAR-1, the methodology suggested in this paper has the potential to improve the strength of the petrographic method.

  9. Molecular Control of the Nanoscale: Effect of Phosphine–Chalcogenide Reactivity on CdS–CdSe Nanocrystal Composition and Morphology

    SciTech Connect (OSTI)

    Ruberu, T. Purnima A.; Albright, Haley R.; Callis, Brandon; Ward, Brittney; Cisneros, Joana; Fan, Hua-Jun; Vela, Javier

    2012-04-22

    We demonstrate molecular control of nanoscale composition, alloying, and morphology (aspect ratio) in CdS–CdSe nanocrystal dots and rods by modulating the chemical reactivity of phosphine–chalcogenide precursors. Specific molecular precursors studied were sulfides and selenides of triphenylphosphite (TPP), diphenylpropylphosphine (DPP), tributylphosphine (TBP), trioctylphosphine (TOP), and hexaethylphosphorustriamide (HPT). Computational (DFT), NMR (31P and 77Se), and high-temperature crossover studies unambiguously confirm a chemical bonding interaction between phosphorus and chalcogen atoms in all precursors. Phosphine–chalcogenide precursor reactivity increases in the order: TPPE < DPPE < TBPE < TOPE < HPTE (E = S, Se). For a given phosphine, the selenide is always more reactive than the sulfide. CdS1–xSex quantum dots were synthesized via single injection of a R3PS–R3PSe mixture to cadmium oleate at 250 °C. X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV/Vis and PL optical spectroscopy reveal that relative R3PS and R3PSe reactivity dictates CdS1–xSex dot chalcogen content and the extent of radial alloying (alloys vs core/shells). CdS, CdSe, and CdS1–xSex quantum rods were synthesized by injection of a single R3PE (E = S or Se) precursor or a R3PS–R3PSe mixture to cadmium–phosphonate at 320 or 250 °C. XRD and TEM reveal that the length-to-diameter aspect ratio of CdS and CdSe nanorods is inversely proportional to R3PE precursor reactivity. Purposely matching or mismatching R3PS–R3PSe precursor reactivity leads to CdS1–xSex nanorods without or with axial composition gradients, respectively. We expect these observations will lead to scalable and highly predictable “bottom-up” programmed syntheses of finely heterostructured nanomaterials with well-defined architectures and properties that are tailored for precise applications.

  10. Boron-carbide-aluminum and boron-carbide-reactive metal cermets. [B/sub 4/C-Al

    DOE Patents [OSTI]

    Halverson, D.C.; Pyzik, A.J.; Aksay, I.A.

    1985-05-06

    Hard, tough, lighweight boron-carbide-reactive metal composites, particularly boron-carbide-aluminum composites, are produced. These composites have compositions with a plurality of phases. A method is provided, including the steps of wetting and reacting the starting materials, by which the microstructures in the resulting composites can be controllably selected. Starting compositions, reaction temperatures, reaction times, and reaction atmospheres are parameters for controlling the process and resulting compositions. The ceramic phases are homogeneously distributed in the metal phases and adhesive forces at ceramic-metal interfaces are maximized. An initial consolidated step is used to achieve fully dense composites. Microstructures of boron-carbide-aluminum cermets have been produced with modules of rupture exceeding 110 ksi and fracture toughness exceeding 12 ksi..sqrt..in. These composites and methods can be used to form a variety of structural elements.

  11. Final Project Report: Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    SciTech Connect (OSTI)

    Jon Chorover, University of Arizona; Peggy O'Ã?Â?Ã?Â?Day, University of California, Merced; Karl Mueller, Penn State University; Wooyong Um, Pacific Northwest National Laboratory; Carl Steefel, Lawrence Berkeley National Laboratory

    2012-10-01

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided detailed characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions.

  12. Development of EEM based silicon–water and silica–water wall potentials for non-reactive molecular dynamics simulations

    SciTech Connect (OSTI)

    Kim, Junghan; Iype, Eldhose; Frijns, Arjan J.H.; Nedea, Silvia V.; Steenhoven, Anton A. van

    2014-07-01

    Molecular dynamics simulations of heat transfer in gases are computationally expensive when the wall molecules are explicitly modeled. To save computational time, an implicit boundary function is often used. Steele's potential has been used in studies of fluid–solid interface for a long time. In this work, the conceptual idea of Steele's potential was extended in order to simulate water–silicon and water–silica interfaces. A new wall potential model is developed by using the electronegativity-equalization method (EEM), a ReaxFF empirical force field and a non-reactive molecular dynamics package PumMa. Contact angle simulations were performed in order to validate the wall potential model. Contact angle simulations with the resulting tabulated wall potentials gave a silicon–water contact angle of 129°, a quartz–water contact angle of 0°, and a cristobalite–water contact angle of 40°, which are in reasonable agreement with experimental values.

  13. Evolution of Structure-Reactivity Correlations for the Hydrogen Abstraction Reaction by Hydroxyl Radical and Comparison with that by Chlorine Atom

    SciTech Connect (OSTI)

    Poutsma, Marvin L

    2013-01-01

    A structure-reactivity correlation for the reaction (HO + HCR3 HOH + CR3 ) has been formulated: log k298(per H) = 0.000630 rH2 0.151 rH 1.056 F 1.053 R 21.26 (r2 = 0.885; n = 70; mean unsigned deviation = 0.29 log units), where rH is the reaction enthalpy and F and R represent the dissection of Hammett s para constant into its field/inductive and resonance effects, and compared for the analogous case for Cl (ref 1). Although more exothermic, the dependence of HO on rH is somewhat greater than Cl . However the dependence on F and R is much less, suggestive of less charge separation in the transition state for the less electronegative HO . The range of k(OH) is significantly less than that of Cl , i.e., it is less dependent on substrate structure. Yet a cross-over exists such that k(Cl) > k(HO) predominates for more reactive cases whereas k(Cl) < k(OH) characterizes the less reactive. The Arrhenius parameters reveal that this cross-over results from a change in {E(Cl) E(OH)} from negative to positive. In contrast, whereas the A factors for both increase significantly as reactivity increases, {A(Cl) / A(OH)} always exceeds unity.

  14. Expression of Autoactivated Stromelysin-1 in Mammary Glands of Transgenic Mice Leads to a Reactive Stroma During Early Development

    SciTech Connect (OSTI)

    Thomasset, N.; Lochter, A.; Sympson, C.J.; Lund, L.R.; Williams, D.R.; Behrendtsen, O.; Werb, Z.; Bissell, M.J.

    1998-04-24

    Extracellular matrix and extracellular matrix-degrading matrix metalloproteinases play a key role in interactions between the epithelium and the mesenchyme during mammary gland development and disease. In patients with breast cancer, the mammary mesenchyme undergoes a stromal reaction, the etiology of which is unknown. We previously showed that targeting of an autoactivating mutant of the matrix metalloproteinase stromelysin-1 to mammary epithelia of transgenic mice resulted in reduced mammary function during pregnancy and development of preneoplastic and neoplastic lesions. Here we examine the cascade of alterations before breast tumor formation in the mammary gland stroma once the expression of the stromelysin-1 transgene commences. Beginning in postpubertal virgin animals, low levels of transgene expression in mammary epithelia led to increased expression of endogenous stromelysin-1 in stromal fibroblasts and up-regulation of other matrix metalloproteinases, without basement membrane disruption. These changes were accompanied by the progressive development of a compensatory reactive stroma, characterized by increased collagen content and vascularization in glands from virgin mice. This remodeling of the gland affected epithelial-mesenchymal communication as indicated by inappropriate expression of tenascin-C starting by day 6 of pregnancy. This, together with increased transgene expression, led to basement membrane disruption starting by day 15 of pregnancy. We propose that the highly reactive stroma provides a prelude to breast epithelial tumors observed in these animals. Epithelial development depends on an exquisite series of inductive and instructive interactions between the differentiating epithelium and the mesenchymal (stromal) compartment. The epithelium, which consists of luminal and myoepithelial cells, is separated from the stroma by a basement membrane (BM), which plays a central role in mammary gland homeostasis and gene expression. In vivo, stromal cells produce fibronectin, collagens, proteoglycans, and some components of the BM, as well as a number of proteinases that can effectively degrade BM constituents. Stromal and epithelial cells of the mammary gland interact to regulate BM synthesis and degradation and, thus, mammary function. Matrix metalloproteinases (MMPs) are extracellular matrix (ECM)-degrading enzymes involved in mammary gland morphogenesis and involution. During late pregnancy and lactation, when the gland becomes fully functional, the expression of MMPs is low however, during involution, when the gland loses function and is remodeled, synthesis of ECM-degrading proteinases increases dramatically.11 Disturbance of the balance between MMPs and MMP inhibitors leads to either unscheduled involution or prolonged lactation. Mammary glands of virgin mice expressing an autoactivating stromelysin-1 (SL-1) transgene display supernumerary branches and precocious alveolar development, accompanied by the synthesis of {beta}-casein at levels found normally only during early pregnancy. During late pregnancy, increased expression of the SL-1 transgene leads to a reduction in expression of pregnancy-specific genes. Later in life, some SL-1 transgenic mice develop hyperplastic, dysplastic, and ductal carcinoma in situ-like lesions, as well as malignant tumors. Little is known about the sequence of changes that occurs before formation of an overt reactive stroma in breast cancer. In the present study, we address the question of whether and how the stromal compartment is altered as a consequence of inappropriate SL-1 transgene expression in the epithelium.

  15. Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

    SciTech Connect (OSTI)

    Smietana, Michael J.; Arruda, Ellen M.; Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109; Program in Macromolecular Science and Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109 ; Faulkner, John A.; Brooks, Susan V.; Molecular and Integrative Physiology, University of Michigan, 2025 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200 ; Larkin, Lisa M.

    2010-12-03

    Research highlights: {yields} Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. {yields} Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. {yields} Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1{sup -/-} mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1{sup -/-} mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm{sup 2}) and strength (MPa) is diminished in Sod1{sup -/-} compared to WT mice. Femurs were obtained from male and female WT and Sod1{sup -/-} mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1{sup -/-} mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1{sup -/-} mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1{sup -/-} mice may represent an appropriate model for studying disease processes in aging bone.

  16. Towards a specific reaction parameter density functional for reactive scattering of H{sub 2} from Pd(111)

    SciTech Connect (OSTI)

    Boereboom, J. M.; Wijzenbroek, M.; Somers, M. F.; Kroes, G. J.

    2013-12-28

    Recently, an implementation of the specific reaction parameter (SRP) approach to density functional theory (DFT) was used to study several reactive scattering experiments of H{sub 2} on Cu(111). It was possible to obtain chemical accuracy (1 kcal/mol ? 4.2 kJ/mol), and therefore, accurately model this paradigmatic example of activated H{sub 2} dissociation on a metal surface. In this work, the SRP-DFT methodology is applied to the dissociation of hydrogen on a Pd(111) surface, in order to test whether the SRP-DFT approach is also applicable to non-activated H{sub 2}-metal systems. In the calculations, the Born–Oppenheimer static surface approximations are used. A comparison to molecular beam sticking experiments, performed at incidence energies ?125 meV, on H{sub 2} + Pd(111) suggested the PBE-vdW [where the Perdew, Burke, and Ernzerhof (PBE) correlation is replaced by van der Waals correlation] functional as a candidate SRP density functional describing the reactive scattering of H{sub 2} on Pd(111). Unfortunately, quantum dynamics calculations are not able to reproduce the molecular beam sticking results for incidence energies <125 meV. From a comparison to initial state-resolved (degeneracy averaged) sticking probabilities it seems clear that for H{sub 2} + Pd(111) dynamic trapping and steering effects are important, and that these effects are not yet well modeled with the potential energy surfaces considered here. Applying the SRP-DFT method to systems where H{sub 2} dissociation is non-activated remains difficult. It is suggested that a density functional that yields a broader barrier distribution and has more non-activated pathways than PBE-vdW (i.e., non-activated dissociation at some sites but similarly high barriers at the high energy end of the spectrum) should allow a more accurate description of the available experiments. Finally, it is suggested that new and better characterized molecular beam sticking experiments be done on H{sub 2} + Pd(111), to facilitate the development of a more accurate theoretical description of this system.

  17. Direct experimental evidence for differing reactivity alterations of minerals following irradiation: The case of calcite and quartz

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

    Pignatelli, Isabella; Kumar, Aditya; Field, Kevin G.; Wang, Bu; Yu, Yingtian; Le Pape, Yann; Bauchy, Mathieu; Sant, Gaurav

    2016-01-29

    Concrete, used in the construction of nuclear power plants (NPPs), may be exposed to radiation emanating from the reactor core. Until recently, concrete has been assumed immune to radiation exposure. Direct evidence acquired on Ar+ -ion irradiated calcite and quartz indicates, on the contrary, that, such minerals, which constitute aggregates in concrete, may be significantly altered by irradiation. More specifically, while quartz undergoes disordering of its atomic structure resulting in a near complete lack of periodicity, calcite only experiences random rotations, and distortions of its carbonate groups. As a result, irradiated quartz shows a reduction in density of around 15%,more » and an increase in chemical reactivity, described by its dissolution rate, similar to a glassy silica. However, calcite shows little change in dissolution rate - although its density noted to reduce by 9%. These differences are correlated with the nature of bonds in these minerals, i.e., being dominantly ionic or covalent, and the rigidity of the mineral's atomic network that is characterized by the number of topological constraints (nc) that are imposed on the atoms in the network. Our outcomes have major implications on the durability of concrete structural elements formed with calcitic or quartzitic aggregates in nuclear power plants.« less

  18. Reactivity Screening of Anatase TiO2 Nanotube Arrays and Anatase Thin Films: A Surface Chemistry Point of View

    SciTech Connect (OSTI)

    Funk, S.; Hokkanen, B.; Nurkic, T.; Goering, J.; Kadossov, E.; Burghaus, Uwe; Ghicov, A.; Schmuki, P.; Yu, Zhongqing; Thevuthasan, Suntharampillai; Saraf, Laxmikant V.

    2008-09-19

    As a reactivity screening we collected thermal desorption spectroscopy (TDS) data of iso-butane, O2, CO2, and CO adsorbed on ordered TiO2 nanotube (TiNTs) arrays. As a reference system iso-butane adsorption on an anatase TiO2 thin film has been considered as well. The as-grown TiNTs are vertically aligned and amorphous. Polycrystalline (poly.) anatase or poly. anatase/rutile mixed nanotubes are formed by annealing confirmed by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The anatase thin film was grown on SrTiO3(001) and characterized by XRD and atomic force microscopy (AFM). Surprisingly, oxygen distinctly interacts with the TiNTs whereas this process is not observed on fully oxidized single crystal rutile TiO2(110). Desorption temperatures of 110-150 K and 100-120 K were observed for CO2 and CO, respectively, on the TiNTs. Variations in the binding energies of the alkanes on TiNTs and anatase thin films also were present, i.e., a structure-activity relationship (SAR) is evident.

  19. Performance of Transuranic-Loaded Fully Ceramic Micro-Encapsulated Fuel in LWRs Final Report, Including Void Reactivity Evaluation

    SciTech Connect (OSTI)

    Michael A. Pope; R. Sonat Sen; Brian Boer; Abderrafi M. Ougouag; Gilles Youinou

    2011-09-01

    The current focus of the Deep Burn Project is on once-through burning of transuranics (TRU) in light-water reactors (LWRs). The fuel form is called Fully-Ceramic Micro-encapsulated (FCM) fuel, a concept that borrows the tri-isotropic (TRISO) fuel particle design from high-temperature reactor technology. In the Deep Burn LWR (DB-LWR) concept, these fuel particles are pressed into compacts using SiC matrix material and loaded into fuel pins for use in conventional LWRs. The TRU loading comes from the spent fuel of a conventional LWR after 5 years of cooling. Unit cell and assembly calculations have been performed using the DRAGON-4 code to assess the physics attributes of TRU-only FCM fuel in an LWR lattice. Depletion calculations assuming an infinite lattice condition were performed with calculations of various reactivity coefficients performed at each step. Unit cells and assemblies containing typical UO2 and mixed oxide (MOX) fuel were analyzed in the same way to provide a baseline against which to compare the TRU-only FCM fuel. Then, assembly calculations were performed evaluating the performance of heterogeneous arrangements of TRU-only FCM fuel pins along with UO2 pins.

  20. Molecular-Level Insights into the Reactivity of Siloxane-Based Electrolytes at a Lithium-Metal Anode

    SciTech Connect (OSTI)

    Assary, Rajeev S.; Lu, Jun; Luo, Xiangyi; Zhang, Xiaoyi; Ren, Yang; Wu, Huiming; Albishri, Hassan M.; El-Hady, D. A.; Al-Bogami, A. S.; Curtiss, Larry A.; Amine, Khalil

    2014-07-21

    A molecular-level understanding of the reactions that occur at the lithium-metal anode/electrolyte interphase is essential to improve the performance of Li–O2 batteries. Experimental and computational techniques are applied to explore the reactivity of tri(ethylene glycol)-substituted trimethylsilane (1NM3), a siloxane-based ether electrolyte, at the lithium-metal anode. In situ/ex situ X-ray diffraction and Fourier-transform infrared spectroscopy studies provide evidence of the formation of lithium hydroxide and lithium carbonates at the anode upon gradual degradation of the metallic lithium anode and the solvent molecules in the presence of oxygen. Density functional calculations performed to obtain a mechanistic understanding of the reductive decomposition of 1NM3 indicate that the decomposition does not require any apparent barrier to produce lithium hydroxide and lithium carbonates when the reduced 1NM3 solvent molecules interact with the oxygen crossing over from the cathode. This study indicates that degradation may be more significant in the case of the 1NM3 solvent, compared to linear ethers such as tetraglyme or dioxalone, because of its relatively high electron affinity. Also, both protection of the lithium metal and prevention of oxygen crossover to the anode are essential for minimizing electrolyte and anode decomposition.

  1. Hydrogen Reactivity on Highly-hydroxylated TiO2(110) Surfaces Prepared via Carboxylic Acid Adsorption and Photolysis

    SciTech Connect (OSTI)

    Du, Yingge; Petrik, Nikolay G.; Deskins, N. Aaron; Wang, Zhitao; Henderson, Michael A.; Kimmel, Gregory A.; Lyubinetsky, Igor

    2012-02-27

    Combined scanning tunneling microscopy, temperature-programmed desorption, photo stimulated desorption, and density functional theory studies have probed the formation and reactivity of highly-hydroxylated rutile TiO2(110) surfaces, which were prepared via a novel, photochemical route using trimethyl acetic acid (TMAA) dissociative adsorption and subsequent photolysis at 300 K. Deprotonation of TMAA molecules upon adsorption produces both surface bridging hydroxyls (OHb) and bidentate trimethyl acetate (TMA) species with a saturation coverage of near 0.5 monolayer (ML). Ultra-violet light irradiation selectively removes TMA species, producing a highly-hydroxylated surface with up to ~0.5 ML OHb coverage. At high coverages, the OHb species typically occupy second-nearest neighbor sites along the bridging oxygen row locally forming linear (2×1) structures of different lengths, although the surface is less ordered on a long scale. The annealing of the highly-hydroxylated surface leads to hydroxyl recombination and H2O desorption with ~100% yield, thus ruling out the diffusion of H into the bulk that has been suggested in the literature. In agreement with experimental data, theoretical results show that the recombinative H2O desorption is preferred over both H bulk diffusion and H2 desorption processes.

  2. Reactivity transients during a blowdown in a MSIV (Main Steam Isolation Valves) closure ATWS (Anticipated Transients Without Scram)

    SciTech Connect (OSTI)

    Cheng, H.S.; Diamond, D.J.

    1988-01-01

    The objectives of this work are to study the consequences of the reactivity transients during a blowdown in an ATWS event with closure of the Main Steam Isolation Valves (MSIV), and to evaluate the effect of the LPCI (Low Pressure Coolant Injection) system and the sensitivity of plant response to the feedback coefficients. The present work was performed with the BNL Plant Analyzer (BPA). The BPA is a on-line, interactive BWR system code which models the non-homogeneous, non-equilibrium two-phase flow with a drift flux mixture model, the reactor kinetics with a point kinetic model, the thermal conduction with an integral method, and the control and plant protection systems with modern control theory. It also models the balance of plant (BOP) as well as the Mark I containment of a BWR/4. Thus, the BPA is a comprehensive engineering plant analyzer transients as well as accidents (e.g., ATWS and Small Break Loss of Coolant Accidents).

  3. Correlation of photothermal conversion on the photo-induced deformation of amorphous carbon nitride films prepared by reactive sputtering

    SciTech Connect (OSTI)

    Harata, T.; Aono, M. Kitazawa, N.; Watanabe, Y.

    2014-08-04

    The photo-induced deformation of hydrogen-free amorphous carbon nitride (a-CN{sub x}) films was investigated under visible-light illumination. The films gave rise to photothermal conversion by irradiation. In this study, we investigated the effects of thermal energy generated by irradiation on the deformation of a-CN{sub x}/ultrathin substrate bimorph specimens. The films were prepared on both ultrathin Si and SiO{sub 2} substrates by reactive radio-frequency magnetron sputtering from a graphite target in the presence of pure nitrogen gas. The temperature of the film on the SiO{sub 2} substrate increased as the optical band-gap of the a-CN{sub x} was decreased. For the film on Si, the temperature remained constant. The deformation degree of the films on Si and SiO{sub 2} substrates were approximately the same. Thus, the deformation of a-CN{sub x} films primarily induced by photon energy directly.

  4. Examples of Department of Energy Successes for Remediation of Contaminated Groundwater: Permeable Reactive Barrier and Dynamic Underground Stripping ASTD Projects

    SciTech Connect (OSTI)

    Purdy, C.; Gerdes, K.; Aljayoushi, J.; Kaback, D.; Ivory, T.

    2002-02-27

    Since 1998, the Department of Energy's (DOE) Office of Environmental Management has funded the Accelerated Site Technology Deployment (ASTD) Program to expedite deployment of alternative technologies that can save time and money for the environmental cleanup at DOE sites across the nation. The ASTD program has accelerated more than one hundred deployments of new technologies under 76 projects that focus on a broad spectrum of EM problems. More than 25 environmental restoration projects have been initiated to solve the following types of problems: characterization of the subsurface using chemical, radiological, geophysical, and statistical methods; treatment of groundwater contaminated with DNAPLs, metals, or radionuclides; and other projects such as landfill covers, purge water management systems, and treatment of explosives-contaminated soils. One of the major goals of the ASTD Program is to deploy a new technology or process at multiple DOE sites. ASTD projects are encouraged to identify subsequent deployments at other sites. Some of the projects that have successfully deployed technologies at multiple sites focusing on cleanup of contaminated groundwater include: Permeable Reactive Barriers (Monticello, Rocky Flats, and Kansas City), treating uranium and organics in groundwater; and Dynamic Underground Stripping (Portsmouth, and Savannah River), thermally treating DNAPL source zones. Each year more and more new technologies and approaches are being used at DOE sites due to the ASTD program. DOE sites are sharing their successes and communicating lessons learned so that the new technologies can replace the baseline or standard approaches at DOE sites, thus expediting cleanup and saving money.

  5. Processing Plan for Potentially Reactive/Ignitable Remote Handled Transuranic Waste at the Idaho Cleanup Project - 12090

    SciTech Connect (OSTI)

    Troescher, Patrick D.; Hobbes, Tammy L.; Anderson, Scott A.

    2012-07-01

    Remote Handle Transuranic (RH-TRU) Waste generated at Argonne National Laboratory - East, from the examination of irradiated and un-irradiated fuel pins and other reactor materials requires a detailed processing plan to ensure reactive/ignitable material is absent to meet WIPP Waste Acceptance Criteria prior to shipping and disposal. The Idaho Cleanup Project (ICP) approach to repackaging Lot 2 waste and how we ensure prohibited materials are not present in waste intended for disposal at Waste Isolation Pilot Plant 'WIPP' uses an Argon Repackaging Station (ARS), which provides an inert gas blanket. Opening of the Lot 2 containers under an argon gas blanket is proposed to be completed in the ARS. The ARS is an interim transition repackaging station that provides a mitigation technique to reduce the chances of a reoccurrence of a thermal event prior to rendering the waste 'Safe'. The consequences, should another thermal event be encountered, (which is likely) is to package the waste, apply the reactive and or ignitable codes to the container, and store until the future treatment permit and process are available. This is the same disposition that the two earlier containers in the 'Thermal Events' were assigned. By performing the initial handling under an inert gas blanket, the waste can sorted and segregate the fines and add the Met-L-X to minimize risk before it is exposed to air. The 1-gal cans that are inside the ANL-E canister will be removed and each can is moved to the ARS for repackaging. In the ARS, the 1-gal can is opened in the inerted environment. The contained waste is sorted, weighed, and visually examined for non compliant items such as unvented aerosol cans and liquids. The contents of the paint cans are transferred into a sieve and manipulated to allow the fines, if any, to be separated into the tray below. The fines are weighed and then blended with a minimum 5:1 mix of Met-L-X. Other debris materials found are segregated from the cans into containers for later packaging. Recoverable fissile waste material (Fuel and fuel-like pieces) suspected of containing sodium bonded pieces) are segregated and will remain in the sieve or transferred to a similar immersion basket in the ARS. The fuel like pieces will be placed into a container with sufficient water to cover the recoverable fissile waste. If a 'reactive characteristic' is present the operator will be able to observe the formation of 'violent' hydrogen gas bubbles. When sodium bonded fuel-like pieces are placed in water the expected reaction is a non-violent reaction that does not meet the definition of reactivity. It is expected that there will be a visible small stream of bubbles present if there is any sodium-bonded fuel-like piece placed in the water. The test will be completed when there is no reaction or the expected reaction is observed..At that point, the fuel like pieces complete the processing cycle in preparation for characterization and shipment to WIPP. If a violent reaction occurs, the fuel-like pieces will be removed from the water, split into the required fissile material content, placed into a screened basket in a 1 gallon drum and drummed out of the hot cell with appropriate RCRA codes applied and placed into storage until sodium treatment is available. These 'violent' reactions will be evidenced by gas bubbles being evolved at the specimen surface where sodium metal is present. The operators will be trained to determine if the reaction is 'violent' or 'mild'. If a 'violent' reaction occurs, the sieve will be immediately removed from the water, placed in a 1 gallon paint can, canned in the argon cover gas and removed from the hot cell to await a future treatment. If the reaction is 'mild', the sieve will then be removed from the water; the material weighed for final packaging and allowed to dry by air exposure. Lot 2 waste cans can be opened, sorted, processed, and weighed while mitigating the potential of thermal events that could occur prior to exposing to air. Exposure to air is a WIPP compliance step demonstrating the absence of react

  6. Constitutive NF-?B activation and tumor-growth promotion by Romo1-mediated reactive oxygen species production

    SciTech Connect (OSTI)

    Chung, Jin Sil; Lee, Sora; Yoo, Young Do

    2014-08-08

    Highlights: • Romo1 expression is required for constitutive nuclear DNA-binding activity of NF-?B. • Romo1 depletion suppresses tumor growth in vivo. • Romo1 presents a potential therapeutic target for diseases. - Abstract: Deregulation of nuclear factor-?B (NF-?B) and related pathways contribute to tumor cell proliferation and invasion. Mechanisms for constitutive NF-?B activation are not fully explained; however, the underlying defects appear to generate and maintain pro-oxidative conditions. In hepatocellular carcinoma (HCC) tissues, up-regulation of reactive oxygen species modulator 1 (Romo1) correlates positively with tumor size. In the present study, we showed that Romo1 expression is required to maintain constitutive nuclear DNA-binding activity of NF-?B and transcriptional activity through constitutive I?B? phosphorylation. Overexpression of Romo1 promoted p65 nuclear translocation and DNA-binding activity. We also show that Romo1 depletion suppressed anchorage-independent colony formation by HCC cells and suppressed tumor growth in vivo. Based on these findings, Romo1 may be a principal regulatory factor in the maintenance of constitutive NF-?B activation in tumor cells. In the interest of anti-proliferative treatments for cancer, Romo1 may also present a productive target for drug development.

  7. Nanofabrication of sharp diamond tips by e-beam lithography and inductively coupled plasma reactive ion etching.

    SciTech Connect (OSTI)

    Moldovan, N.; Divan, R.; Zeng, H.; Carlisle, J. A.; Advanced Diamond Tech.

    2009-12-07

    Ultrasharp diamond tips make excellent atomic force microscopy probes, field emitters, and abrasive articles due to diamond's outstanding physical properties, i.e., hardness, low friction coefficient, low work function, and toughness. Sharp diamond tips are currently fabricated as individual tips or arrays by three principal methods: (1) focused ion beam milling and gluing onto a cantilever of individual diamond tips, (2) coating silicon tips with diamond films, or (3) molding diamond into grooves etched in a sacrificial substrate, bonding the sacrificial substrate to another substrate or electrodepositing of a handling chip, followed by dissolution of the sacrificial substrate. The first method is tedious and serial in nature but does produce very sharp tips, the second method results in tips whose radius is limited by the thickness of the diamond coating, while the third method involves a costly bonding and release process and difficulties in thoroughly filling the high aspect ratio apex of molding grooves with diamond at the nanoscale. To overcome the difficulties with these existing methods, this article reports on the feasibility of the fabrication of sharp diamond tips by direct etching of ultrananocrystalline diamond (UNCD{reg_sign}) as a starting and structural material. The UNCD is reactive ion etched using a cap-precursor-mask scheme. An optimized etching recipe demonstrates the formation of ultrasharp diamond tips ({approx} 10 nm tip radius) with etch rates of 650 nm/min.

  8. Boiling water reactor fuel behavior at burnup of 26 GWd/tonne U under reactivity-initiated accident conditions

    SciTech Connect (OSTI)

    Nakamura, Takehiko; Yoshinaga, Makio . Dept. of Reactor Safety Research); Sobajima, Makoto ); Ishijima, Kiyomi; Fujishiro, Toshio . Dept. of Reactor Safety Research)

    1994-10-01

    Irradiated boiling water reactor (BWR) fuel behavior under reactivity-initiated accident (RIA) conditions was investigated in the Nuclear Safety Research Reactor (NSRR) of the Japan Atomic Energy Research Institute. Short test fuel rods, refabricated from a commercial 7 x 7 type BWR fuel rod at a burnup of 26 GWd/ tonne U, were pulse irradiated in the NSRR under simulated cooled startup RIA conditions of the BWRs. Thermal energy from 230 J/g fuel (55 cal/g fuel) to 410 J/g fuel (98 cal/g fuel) was promptly subjected to the test fuel rods by pulse irradiation within [approximately] 10 ms. The peak fuel enthalpies are believed to be the same as the prompt energy depositions. The test fuel rods demonstrated characteristic behavior of the irradiated fuel rods under the accident conditions, such as enhanced pellet cladding mechanical interaction (PCMI) and fission gas release. However, all the fuel rods survived the accident conditions with considerable margins. Simulations by the FRAP-T6 code and fresh fuel rod tests under the same RIA conditions highlighted the burnup effects on the accident fuel performance. The tests and the simulation suggested that the BWR fuel would possibly fail by a cladding burst due to fission gas release during the cladding temperature escalation rather than the PCMI under the cold startup RIA conditions of a severe power burst.

  9. Visible light-induced photocatalytic properties of WO{sub 3} films deposited by dc reactive magnetron sputtering

    SciTech Connect (OSTI)

    Imai, Masahiro; Kikuchi, Maiko; Oka, Nobuto; Shigesato, Yuzo

    2012-05-15

    The authors examined the photocatalytic activity of WO{sub 3} films (thickness 500-600 nm) deposited on a fused quartz substrate heated at 350-800 deg. C by dc reactive magnetron sputtering using a W metal target under the O{sub 2} gas pressure from 1.0 to 5.0 Pa. Films deposited at 800 deg. C under 5.0 Pa have excellent crystallinity of triclinic, P1(1) structure and a large surface area, as confirmed by x-ray diffraction, scanning electron microscopy, and atomic force microscopy. Exposure of acetaldehyde (CH{sub 3}CHO) adsorbed onto the film surface to ultraviolet, visible, or standard fluorescence light induces oxidative photocatalytic decomposition indicated by a decrease in CH{sub 3}CHO concentration and generation of CO{sub 2} gas. For all three types of irradiation, concentration ratio of decreased CH{sub 3}CHO to increased CO{sub 2} is about 1:1, suggesting the possible presence of intermediates. The sputter-deposited WO{sub 3} film can be a good candidate as a visible light-responsive photocatalyst.

  10. Effect of Doping on Surface Reactivity and Conduction Mechanism in Sm-doped CeO2 Thin Films

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

    Yang, Nan; Belianinov, Alex; Strelcov, Evgheni; Tebano, Antonello; Daniele, Dr. Di Castro; Schlueter, Dr. Christoph; Lee, Dr. Tien-Lin; Baddorf, Arthur P; Wisinger, Nina; Jesse, Stephen; et al

    2014-01-01

    Scanning probe microscopy measurements show irreversible surface electrochemistry in Sm-doped CeO2 thin films, which depends on humidity, temperature and doping concentration. A systematic study by electrochemical strain microscopy (ESM) in samples with two different Sm content and in several working conditions allows disclosing the microscopic mechanism underlying the difference in water adsorption and splitting with subsequent proton liberation. We measure the behavior of the hysteresis loops by changing temperature and humidity, both in standard ESM configuration and using the first order reversal curve (FORC) method. Complementing our study with spectroscopic measurements by hard x-ray photoemission spectroscopy we find that watermore » incorporation is favored until the doping with Sm is too high to allow the presence of Ce3+. The influence of doping on the surface reactivity and conduction mechanism clearly emerges from all of our experimental results. We find that at lower Sm concentration proton conduction is prevalent, featured by lower activation energy and higher mobility. Defect concentrations determine the type of the prevalent charge carrier in a doping dependent manner.« less

  11. Pore Scale Modeling of the Reactive Transport of Chromium in the Cathode of a Solid Oxide Fuel Cell

    SciTech Connect (OSTI)

    Ryan, Emily M.; Tartakovsky, Alexandre M.; Recknagle, Kurtis P.; Khaleel, Mohammad A.; Amon, Cristina

    2011-01-01

    We present a pore scale model of a solid oxide fuel cell (SOFC) cathode. Volatile chromium species are known to migrate from the current collector of the SOFC into the cathode where over time they decrease the voltage output of the fuel cell. A pore scale model is used to investigate the reactive transport of chromium species in the cathode and to study the driving forces of chromium poisoning. A multi-scale modeling approach is proposed which uses a cell level model of the cathode, air channel and current collector to determine the boundary conditions for a pore scale model of a section of the cathode. The pore scale model uses a discrete representation of the cathode to explicitly model the surface reactions of oxygen and chromium with a cathode material. The pore scale model is used to study the reaction mechanisms of chromium by considering the effects of reaction rates, diffusion coefficients, chromium vaporization, and oxygen consumption on chromium’s deposition in the cathode. The study shows that chromium poisoning is most significantly affected by the chromium reaction rates in the cathode and that the reaction rates are a function of the local current density in the cathode.

  12. Building Conceptual Models of Field-Scale Uranium Reactive Transport in a Dynamic Vadose Zone-Aquifer-River System

    SciTech Connect (OSTI)

    Yabusaki, Steven B.; Fang, Yilin; Waichler, Scott R.

    2008-12-04

    Subsurface simulation is being used to build, test, and couple conceptual process models to better understand controls on a 0.4 km by 1.0 km uranium plume that has persisted above the drinking water standard in the groundwater of the Hanford 300 Area over the last 15 years. At this site, uranium-contaminated sediments in the vadose zone and aquifer are subject to significant variations in water levels and velocities driven by the diurnal, weekly, seasonal, and episodic Columbia River stage dynamics. Groundwater flow reversals typically occur twice a day with significant exchange of river water and groundwater in the near-river aquifer. Mixing of the dilute solution chemistry of the river with the groundwater complicates the uranium sorption behavior as the mobility of U(VI) has been shown experimentally to be a function of pH, carbonate, calcium, and uranium. Furthermore, uranium mass transfer between solid and aqueous phases has been observed to be rate-limited in the context of the high groundwater velocities resulting from the river stage fluctuations and the highly transmissive sediments (hydraulic conductivities ~1500 m/d). One- and two-dimensional vertical cross-sectional simulations of variably-saturated flow and reactive transport, based on laboratory-derived models of distributed rate mass transfer and equilibrium multicomponent surface complexation, are used to assess uranium transport at the dynamic vadose zone – aquifer interface as well as changes to uranium mobility due to incursions of river water into the aquifer.

  13. Non-invasive in situ plasma monitoring of reactive gases using the floating harmonic method for inductively coupled plasma etching application

    SciTech Connect (OSTI)

    Lee, J. H.; Kim, M. J.; Yoon, Y. S.

    2013-04-15

    The floating harmonic method was developed for in situ plasma diagnostics of allowing real time measurement of electron temperature (T{sub e}) and ion flux (J{sub ion}) without contamination of the probe from surface modification by reactive species. In this study, this novel non-invasive diagnostic system was studied to characterize inductively coupled plasma of reactive gases monitoring T{sub e} and J{sub ion} for investigating the optimum plasma etching conditions and controlling of the real-time plasma surface reaction in the range of 200-900 W source power, 10-100 W bias power, and 3-15 mTorr chamber pressure, respectively.

  14. A SCOPING STUDY: Development of Probabilistic Risk Assessment Models for Reactivity Insertion Accidents During Shutdown In U.S. Commercial Light Water Reactors

    SciTech Connect (OSTI)

    S. Khericha

    2011-06-01

    This report documents the scoping study of developing generic simplified fuel damage risk models for quantitative analysis from inadvertent reactivity insertion events during shutdown (SD) in light water pressurized and boiling water reactors. In the past, nuclear fuel reactivity accidents have been analyzed both mainly deterministically and probabilistically for at-power and SD operations of nuclear power plants (NPPs). Since then, many NPPs had power up-rates and longer refueling intervals, which resulted in fuel configurations that may potentially respond differently (in an undesirable way) to reactivity accidents. Also, as shown in a recent event, several inadvertent operator actions caused potential nuclear fuel reactivity insertion accident during SD operations. The set inadvertent operator actions are likely to be plant- and operation-state specific and could lead to accident sequences. This study is an outcome of the concern which arose after the inadvertent withdrawal of control rods at Dresden Unit 3 in 2008 due to operator actions in the plant inadvertently three control rods were withdrawn from the reactor without knowledge of the main control room operator. The purpose of this Standardized Plant Analysis Risk (SPAR) Model development project is to develop simplified SPAR Models that can be used by staff analysts to perform risk analyses of operating events and/or conditions occurring during SD operation. These types of accident scenarios are dominated by the operator actions, (e.g., misalignment of valves, failure to follow procedures and errors of commissions). Human error probabilities specific to this model were assessed using the methodology developed for SPAR model human error evaluations. The event trees, fault trees, basic event data and data sources for the model are provided in the report. The end state is defined as the reactor becomes critical. The scoping study includes a brief literature search/review of historical events, developments of a small set of comprehensive event trees and fault trees and recommendation for future work.

  15. Reactivity of pulverized coals during combustion catalyzed by CeO{sub 2} and Fe{sub 2}O{sub 3}

    SciTech Connect (OSTI)

    Gong, Xuzhong; Guo, Zhancheng; Wang, Zhi

    2010-02-15

    Effects of CeO{sub 2} and Fe{sub 2}O{sub 3} on combustion reactivity of several fuels, including three ranks of coals, graphite and anthracite chars, were investigated using thermo-gravimetric analyzer. The results indicated that the combustion reactivity of all the samples except lignite was improved with CeO{sub 2} or Fe{sub 2}O{sub 3} addition. It was interesting to note that the ignition temperatures of anthracite were decreased by 50 C and 53 C, respectively, with CeO{sub 2} and Fe{sub 2}O{sub 3} addition and that its combustion rates were increased to 15.4%/min and 12.2%/min. Ignition temperatures of lignite with CeO{sub 2} and Fe{sub 2}O{sub 3} addition were 250 C and 226 C, and the combustion rates were 12.8% and 19.3%/min, respectively. When compared with those of lignite without catalysts, no obvious catalytic effects of the two catalysts on its combustion reactivity were revealed. The results from the combustion of the three rank pulverized coals catalyzed by CeO{sub 2} and Fe{sub 2}O{sub 3} indicated significant effects of the two catalysts on fixed carbon combustion. And it was found that the higher the fuel rank, the better the catalytic effect. The results of combustion from two kinds of anthracite chars showed obvious effects of anthracite pyrolysis catalyzed by CeO{sub 2} and Fe{sub 2}O{sub 3} on its combustion reactivity. (author)

  16. Variation of char structure during anthracite pyrolysis catalyzed by Fe{sub 2}O{sub 3} and its influence on char combustion reactivity

    SciTech Connect (OSTI)

    Xuzhong Gong; Zhancheng Guo; Zhi Wang

    2009-09-15

    Effects of Fe{sub 2}O{sub 3} on the pyrolysis reactivity of demineralized anthracite were investigated by a thermo-gravimetric analyzer, indicating that pyrolysis reactivity of Fe{sub 2}O{sub 3}-loaded demineralized anthracite was higher than that of raw demineralized anthracite when temperature is over 500{sup o}C. Chars were prepared from the two coal samples in muffle with heating progress, and their structures were analyzed using SEM, FTIR, XRD, and Raman. FTIR results showed that absorption peaks of functional groups on the surface of char from catalytic pyrolysis at 700{sup o}C were more than that of char from noncatalytic pyrolysis. Raman results demonstrated values of (I{sub D3} + I{sub D4})/IG of chars from catalytic pyrolysis and noncatalytic pyrolysis were 4.76 and 3.86, respectively, indicating that ordering of the char was decreased by Fe{sub 2}O{sub 3}. XRD analysis revealed that diffraction angle of the 002 peak did not shift; however, L{sub a} and L{sub c} decreased, indicating degree of graphitization for microcrystalline structure of char from catalytic pyrolysis was decreased. The results of FTIR, XRD, and Raman of the char showed that catalytic pyrolysis improved the formation of free radicals, while hindered polymerization and forming of basic structure units. Finally, combustion reactivity of the three chars, including char of raw demineralized anthracite (char-A), char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite (char-B), and char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite washed by HCl (char-C), was investigated using TG and indicated that their active order was char-B > char-C > char-A. The results corroborated that Fe{sub 2}O{sub 3} changed structure of anthracite char and improved combustion reactivity.

  17. Reactivity-worth estimates of the OSMOSE samples in the MINERVE reactor R1-MOX, R2-UO2 and MORGANE/R configurations.

    SciTech Connect (OSTI)

    Zhong, Z.; Klann, R. T.; Nuclear Engineering Division

    2007-08-03

    An initial series of calculations of the reactivity-worth of the OSMOSE samples in the MINERVE reactor with the R2-UO2 and MORGANE/R core configuration were completed. The calculation model was generated using the lattice physics code DRAGON. In addition, an initial comparison of calculated values to experimental measurements was performed based on preliminary results for the R1-MOX configuration.

  18. Atmospheric lifetimes and global warming potentials of hydrofluoroethers: Reactivity toward OH, UV spectra, and IR absorption cross sections

    SciTech Connect (OSTI)

    Orkin, V.L.; Villenave, E.; Huie, R.E.; Kurylo, M.J.

    1999-12-02

    The rate constants for the reactions of OH radicals with the fluorinated ethers, CHF{sub 2}-O-CHF{sub 2} (HFOC-134) and CF{sub 3}CH{sub 2}-O-CH{sub 2}CF{sub 3} (HFOC-356mff), were measured using the flash photolysis resonance fluorescence technique over the temperature range 277--370 K to give the following Arrhenius expressions: k{sub HFOC-356mff}(T) = (2.32{sub {minus}0.41}{sup +0.46}) x 10{sup {minus}12} exp{l{underscore}brace}{minus}(790 {+-} 47)/T{r{underscore}brace} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. On the basis of the analysis of the available experimental results, the following Arrhenius expression can be recommended for the rate constant of the reaction between OH and HFOC-134: k{sub HFOC-134}(T) = (0.82{sub {minus}0.24}{sup +0.34}) x 10{sup {minus}12} exp{l{underscore}brace}{minus}(1,730 {+-} 110)/T{r{underscore}brace} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. Atmospheric lifetimes were estimated to be 24.8 years for HFOC-134 (23.8 years based on the results of this study alone) and 0.3 years for HFOC-356mff. Infrared absorption cross sections of HFOC-134, HFOC-356mff, and HFOC-125 (CHF{sub 2}-O-CF{sub 3}) were measured at T = 295 K from 500 to 1,600 cm{sup {minus}1} and the global warming potentials of the three compounds were estimated. Ultraviolet absorption spectra of the ethers were measured between 160 and 220 nm. The general pattern of reactivity of hydrofluoroethers toward OH is discussed.

  19. Modeling of coupled heat transfer and reactive transport processesin porous media: Application to seepage studies at Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    Mukhopadhyay, Sumit; Sonnenthal, Eric L.; Spycher, Nicolas

    2007-01-15

    When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) processes dynamically alter the hydrological properties of the rock. A model based on the TOUGHREACT reactive transport software is presented here to investigate the impact of THC processes on flow near an emplacement tunnel at Yucca Mountain, Nevada. We show how transient changes in hydrological properties caused by THC processes often lead to local flow channeling and saturation increases above the tunnel. For models that include only permeability changes to fractures, such local flow channeling may lead to seepage relative to models where THC effects are ignored. However, coupled THC seepage models that include both permeability and capillary changes to fractures may not show this additional seepage.

  20. Phototoxicity of nano titanium dioxides in HaCaT keratinocytes—Generation of reactive oxygen species and cell damage

    SciTech Connect (OSTI)

    Yin, Jun-Jie; Liu, Jun; Ehrenshaft, Marilyn; Roberts, Joan E.; Fu, Peter P.; Mason, Ronald P.; Zhao, Baozhong

    2012-08-15

    Nano-sized titanium dioxide (TiO{sub 2}) is among the top five widely used nanomaterials for various applications. In this study, we determine the phototoxicity of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) with different molecular sizes and crystal forms (anatase and rutile) in human skin keratinocytes under UVA irradiation. Our results show that all nano-TiO{sub 2} particles caused phototoxicity, as determined by the MTS assay and by cell membrane damage measured by the lactate dehydrogenase (LDH) assay, both of which were UVA dose- and nano-TiO{sub 2} dose-dependent. The smaller the particle size of the nano-TiO{sub 2} the higher the cell damage. The rutile form of nano-TiO{sub 2} showed less phototoxicity than anatase nano-TiO{sub 2}. The level of photocytotoxicity and cell membrane damage is mainly dependent on the level of reactive oxygen species (ROS) production. Using polyunsaturated lipids in plasma membranes and human serum albumin as model targets, and employing electron spin resonance (ESR) oximetry and immuno-spin trapping as unique probing methods, we demonstrated that UVA irradiation of nano-TiO{sub 2} can induce significant cell damage, mediated by lipid and protein peroxidation. These overall results suggest that nano-TiO{sub 2} is phototoxic to human skin keratinocytes, and that this phototoxicity is mediated by ROS generated during UVA irradiation. Highlights: ? We evaluate the phototoxicity of nano-TiO{sub 2} with different sizes and crystal forms. ? The smaller the particle size of the nano-TiO{sub 2} the higher the cell damage. ? The rutile form of nano-TiO{sub 2} showed less phototoxicity than anatase nano-TiO{sub 2}. ? ESR oximetry and immuno-spin trapping techniques confirm UVA-induced cell damage. ? Phototoxicity is mediated by ROS generated during UVA irradiation of nano-TiO{sub 2}.

  1. Formation, characterization and dynamics of onion like carbon structures from nanodiamonds using reactive force-fields for electrical energy storage

    SciTech Connect (OSTI)

    Ganesh, Panchapakesan; Kent, Paul R; Mochalin, Vadym N

    2011-01-01

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbon nanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core of the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbon nanostructure appears, with a shell-shell spacing of about {approx}3.4 {angstrom} for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large ({approx}29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.

  2. Formation, characterization, and dynamics of onion-like carbon structures for electrical energy storage from nanodiamonds using reactive force fields

    SciTech Connect (OSTI)

    Ganesh, P.; Kent, P. R. C.; Mochalin, V.

    2011-10-01

    We simulate the experimentally observed graphitization of nanodiamonds into multi-shell onion-like carbonnanostructures, also called carbon onions, at different temperatures, using reactive force fields. The simulations include long-range Coulomb and van der Waals interactions. Our results suggest that long-range interactions play a crucial role in the phase-stability and the graphitization process. Graphitization is both enthalpically and entropically driven and can hence be controlled with temperature. The outer layers of the nanodiamond have a lower kinetic barrier toward graphitization irrespective of the size of the nanodiamond and graphitize within a few-hundred picoseconds, with a large volume increase. The inner core of the nanodiamonds displays a large size-dependent kinetic barrier, and graphitizes much more slowly with abrupt jumps in the internal energy. It eventually graphitizes by releasing pressure and expands once the outer shells have graphitized. The degree of transformation at a particular temperature is thereby determined by a delicate balance between the thermal energy, long-range interactions, and the entropic/enthalpic free energy gained by graphitization. Upon full graphitization, a multi-shell carbonnanostructure appears, with a shell-shell spacing of about ~3.4 Å for all sizes. The shells are highly defective with predominantly five- and seven-membered rings to curve space. Larger nanodiamonds with a diameter of 4 nm can graphitize into spiral structures with a large (~29-atom carbon ring) pore opening on the outermost shell. Such a large one-way channel is most attractive for a controlled insertion of molecules/ions such as Li ions, water, or ionic liquids, for increased electrochemical capacitor or battery electrode applications.

  3. Arsenite induces cell transformation by reactive oxygen species, AKT, ERK1/2, and p70S6K1

    SciTech Connect (OSTI)

    Carpenter, Richard L.; Jiang, Yue; Jing, Yi; He, Jun; Rojanasakul, Yon; Liu, Ling-Zhi; Jiang, Bing-Hua

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer Chronic exposure to arsenite induces cell proliferation and transformation. Black-Right-Pointing-Pointer Arsenite-induced transformation increases ROS production and downstream signalings. Black-Right-Pointing-Pointer Inhibition of ROS levels via catalase reduces arsenite-induced cell transformation. Black-Right-Pointing-Pointer Interruption of AKT, ERK, or p70S6K1 inhibits arsenite-induced cell transformation. -- Abstract: Arsenic is naturally occurring element that exists in both organic and inorganic formulations. The inorganic form arsenite has a positive association with development of multiple cancer types. There are significant populations throughout the world with high exposure to arsenite via drinking water. Thus, human exposure to arsenic has become a significant public health problem. Recent evidence suggests that reactive oxygen species (ROS) mediate multiple changes to cell behavior after acute arsenic exposure, including activation of proliferative signaling and angiogenesis. However, the role of ROS in mediating cell transformation by chronic arsenic exposure is unknown. We found that cells chronically exposed to sodium arsenite increased proliferation and gained anchorage-independent growth. This cell transformation phenotype required constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. We also observed these cells constitutively produce ROS, which was required for the constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. Suppression of ROS levels by forced expression of catalase also reduced cell proliferation and anchorage-independent growth. These results indicate cell transformation induced by chronic arsenic exposure is mediated by increased cellular levels of ROS, which mediates activation of AKT, ERK1/2, and p70S6K1.

  4. Comparative Reactivity Study of Forsterite and Antigorite in Wet Supercritical CO2 by In Situ Infrared Spectroscopy

    SciTech Connect (OSTI)

    Thompson, Christopher J.; Loring, John S.; Rosso, Kevin M.; Wang, Zheming

    2013-10-01

    The carbonation reactions of forsterite (Mg2SiO4) and antigorite [Mg3Si2O5(OH)4], representatives of olivine and serpentine minerals, in dry and wet supercritical carbon dioxide (scCO2) at conditions relevant to geologic carbon sequestration (35 °C and 100 bar) were studied by in-situ Fourier transform infrared (FT-IR) spectroscopy. Our results confirm that water plays a critical role in the reactions between metal silicate minerals and scCO2. For neat scCO2, no reaction was observed in 24 hr for either mineral. When water was added to the scCO2, a thin water film formed on the minerals’ surfaces, and the reaction rates and extents increased as the water saturation level was raised from 54% to 116% (excess water). For the first time, the presence of bicarbonate, a key reaction intermediate for metal silicate reactions with scCO2, was observed in a heterogeneous system where mineral solids, an adsorbed water film, and bulk scCO2 co-exist. In excess-water experiments, approximately 4% of forsterite and less than 2% of antigorite transformed into hydrated Mg-carbonates. A precipitate similar to nesquehonite (MgCO3•3H2O) was observed for forsterite within 6 hr of reaction time, but no such precipitate was formed from antigorite until after water was removed from the scCO2 following a 24-hr reaction period. The reduced reactivity and carbonate-precipitation behavior of antigorite was attributed to slower, incongruent dissolution of the mineral and lower concentrations of Mg2+ and HCO3- in the water film. The in situ measurements employed in this work make it possible to quantify metal carbonate precipitates and key reaction intermediates such as bicarbonate for the investigation of carbonation reaction mechanisms relevant to geologic carbon sequestration.

  5. The structure and reactivity of adsorbates on stepped Rh and Pt surfaces investigated by LEED, HREELS, TPD, XPS and STM

    SciTech Connect (OSTI)

    Batteas, J.D. |

    1995-06-01

    Defects on surfaces such as steps play an important role in surface chemistry. In order to obtain an understanding of the influence of steps in surface chemical reactions, the structure and reactivity of small molecules (O{sub 2}, CO, H{sub 2}S, and C{sub 2}H{sub 4}) on atomically stepped surfaces of RH and Pt have been investigated. The detailed structures of CO and oxygen bonded to the Rh(110) surface were determined. The CO molecules bond near the short bridge sites with the CO molecular axis tilted approximately 24{degree} from the surface normal. Oxygen atoms are bound asymmetrically in the 3-fold fcc hollow-sites to the (111) facets of the steps. The interactions of CO and oxygen on the Rh(311) surface were examined. The reaction of CO with the ordered phases of O shows two distinct reaction channels, a low temperature reaction limited channel (200 K) and a high temperature diffusion limited channel (350 K). Models of the reaction geometry and dynamics are proposed. The thermal decomposition of ethylene was examined on the Rh(311) surface. The stable decomposition species (C{sub 2}H, CH and C{sub 2}) are formed near 300 K, approximately 100 K lower on the stepped Rh(311) than on the flatter Rh(111) surface. The formation of these species at lower temperatures is attributed to the stepped nature of the surface. Finally, in situ STM was used to examine surface structural changes of a stepped Pt(111) crystal under coadsorption of sulfur and CO. This is the first direct evidence for a new mechanism by which a surface covered with an unreactive, strongly chemisorbed overlayer can form new sites, for bonding and reactions to occur, by massive surface restructuring at the step edges. This new surface phenomenon answers some of the puzzles of metal surface catalysis and its implications are described. 278 refs.

  6. Low temperature reactive bonding

    DOE Patents [OSTI]

    Makowiecki, Daniel M. (Livermore, CA); Bionta, Richard M. (Livermore, CA)

    1995-01-01

    The joining technique requires no external heat source and generates very little heat during joining. It involves the reaction of thin multilayered films deposited on faying surfaces to create a stable compound that functions as an intermediate or braze material in order to create a high strength bond. While high temperatures are reached in the reaction of the multilayer film, very little heat is generated because the films are very thin. It is essentially a room temperature joining process.

  7. Reactive decontamination formulation

    DOE Patents [OSTI]

    Giletto, Anthony (College Station, TX); White, William (College Station, TX); Cisar, Alan J. (Cypress, TX); Hitchens, G. Duncan (Bryan, TX); Fyffe, James (Bryan, TX)

    2003-05-27

    The present invention provides a universal decontamination formulation and method for detoxifying chemical warfare agents (CWA's) and biological warfare agents (BWA's) without producing any toxic by-products, as well as, decontaminating surfaces that have come into contact with these agents. The formulation includes a sorbent material or gel, a peroxide source, a peroxide activator, and a compound containing a mixture of KHSO.sub.5, KHSO.sub.4 and K.sub.2 SO.sub.4. The formulation is self-decontaminating and once dried can easily be wiped from the surface being decontaminated. A method for decontaminating a surface exposed to chemical or biological agents is also disclosed.

  8. Low temperature reactive bonding

    DOE Patents [OSTI]

    Makowiecki, D.M.; Bionta, R.M.

    1995-01-17

    The joining technique is disclosed that requires no external heat source and generates very little heat during joining. It involves the reaction of thin multilayered films deposited on faying surfaces to create a stable compound that functions as an intermediate or braze material in order to create a high strength bond. While high temperatures are reached in the reaction of the multilayer film, very little heat is generated because the films are very thin. It is essentially a room temperature joining process. 5 figures.

  9. Chemically Reactive Working Fluids

    Broader source: Energy.gov [DOE]

    This document summarizes the progress of this Argonne National Laboratories project, funded by SunShot, for the second quarter of fiscal year 2013.

  10. Chemically Reactive Working Fluids

    Broader source: Energy.gov [DOE]

    This fact sheet summarizes the Argonne National Laboratory (ANL) project for the DOE Solar Program through the 2012 SunShot Concentrating Solar Power R&D awards.

  11. Crystallization and preliminary X-ray analysis of molecular chaperone-like diol dehydratase-reactivating factor in ADP-bound and nucleotide-free forms

    SciTech Connect (OSTI)

    Mori, Koichi; Hieda, Naoki; Yamanishi, Mamoru; Shibata, Naoki; Toraya, Tetsuo

    2005-06-01

    The molecular chaperone-like reactivating factor for adenosylcobalamin (coenzyme B{sub 12}) dependent diol dehydratase was crystallized in ADP-bound and nucleotide-free forms. Preliminary X-ray analysis indicated that crystals are orthorhombic and diffract to 2.0 Å. Adenosylcobalamin (coenzyme B{sub 12}) dependent diol dehydratase (EC 4.2.1.28) catalyzes the conversion of 1,2-diols and glycerol to the corresponding aldehydes. It undergoes mechanism-based inactivation by glycerol. The diol dehydratase-reactivating factor (DDR) reactivates the inactivated holoenzymes in the presence of adenosylcobalamin, ATP and Mg{sup 2+} by mediating the release of a damaged cofactor. This molecular chaperone-like factor was overexpressed in Escherichia coli, purified and crystallized in the ADP-bound and nucleotide-free forms by the sandwich-drop vapour-diffusion method. The crystals of the ADP-bound form belong to the orthorhombic system, with space group P2{sub 1}2{sub 1}2{sub 1} and unit-cell parameters a = 83.26, b = 84.60, c = 280.09 Å, and diffract to 2.0 Å. In the absence of nucleotide, DDR crystals were orthorhombic, with space group P2{sub 1}2{sub 1}2{sub 1} and unit-cell parameters a = 81.92, b = 85.37, c = 296.99 Å and diffract to 3.0 Å. Crystals of both forms were suitable for structural analysis.

  12. Surface chemical reactivity of ultrathin Pd(111) films on Ru(0001): Importance of orbital symmetry in the application of the d-band model

    SciTech Connect (OSTI)

    Yin, Xiangshi; Cooper, Valentino R.; Weitering, Hanno H.; Snijders, Paul C.

    2015-09-22

    The chemical bonding of adsorbate molecules on transition-metal surfaces is strongly influenced by the hybridization between the molecular orbitals and the metal d-band. The strength of this interaction is often correlated with the location of the metal d-band center relative to the Fermi level. Here, we exploit finite size effects in the electronic structure of ultrathin Pd(111) films grown on Ru(0001) to tune their reactivity by changing the film thickness one atom layer at a time, while keeping all other variables unchanged. Interestingly, while bulk Pd(111) is reactive toward oxygen, Pd(111) films below five monolayers are surprisingly inert. This observation is fully in line with the d-band model prediction when applied to the orbitals involved in the bonding. The shift of the d-band center with film thickness is primarily attributed to shifts in the partial density of states associated with the 4dxz and 4dyz orbitals. This study provides an in-depth look into the orbital specific contributions to the surface chemical reactivity, providing new insights that could be useful in surface catalysis.

  13. Surface chemical reactivity of ultrathin Pd(111) films on Ru(0001): Importance of orbital symmetry in the application of the d-band model

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

    Yin, Xiangshi; Cooper, Valentino R.; Weitering, Hanno H.; Snijders, Paul C.

    2015-09-22

    The chemical bonding of adsorbate molecules on transition-metal surfaces is strongly influenced by the hybridization between the molecular orbitals and the metal d-band. The strength of this interaction is often correlated with the location of the metal d-band center relative to the Fermi level. Here, we exploit finite size effects in the electronic structure of ultrathin Pd(111) films grown on Ru(0001) to tune their reactivity by changing the film thickness one atom layer at a time, while keeping all other variables unchanged. Interestingly, while bulk Pd(111) is reactive toward oxygen, Pd(111) films below five monolayers are surprisingly inert. This observationmore » is fully in line with the d-band model prediction when applied to the orbitals involved in the bonding. The shift of the d-band center with film thickness is primarily attributed to shifts in the partial density of states associated with the 4dxz and 4dyz orbitals. This study provides an in-depth look into the orbital specific contributions to the surface chemical reactivity, providing new insights that could be useful in surface catalysis.« less

  14. Solving iTOUGH2 simulation and optimization problems using the PEST protocol

    SciTech Connect (OSTI)

    Finsterle, S.A.; Zhang, Y.

    2011-02-01

    The PEST protocol has been implemented into the iTOUGH2 code, allowing the user to link any simulation program (with ASCII-based inputs and outputs) to iTOUGH2's sensitivity analysis, inverse modeling, and uncertainty quantification capabilities. These application models can be pre- or post-processors of the TOUGH2 non-isothermal multiphase flow and transport simulator, or programs that are unrelated to the TOUGH suite of codes. PEST-style template and instruction files are used, respectively, to pass input parameters updated by the iTOUGH2 optimization routines to the model, and to retrieve the model-calculated values that correspond to observable variables. We summarize the iTOUGH2 capabilities and demonstrate the flexibility added by the PEST protocol for the solution of a variety of simulation-optimization problems. In particular, the combination of loosely coupled and tightly integrated simulation and optimization routines provides both the flexibility and control needed to solve challenging inversion problems for the analysis of multiphase subsurface flow and transport systems.

  15. Involvement of reactive oxygen species in brominated diphenyl ether-47-induced inflammatory cytokine release from human extravillous trophoblasts in vitro

    SciTech Connect (OSTI)

    Park, Hae-Ryung Kamau, Patricia W.; Loch-Caruso, Rita

    2014-01-15

    Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant compounds. Brominated diphenyl ether (BDE)-47 is one of the most prevalent PBDE congeners found in human breast milk, serum and placenta. Despite the presence of PBDEs in human placenta, effects of PBDEs on placental cell function are poorly understood. The present study investigated BDE-47-induced reactive oxygen species (ROS) formation and its role in BDE-47-stimulated proinflammatory cytokine release in a first trimester human extravillous trophoblast cell line, HTR-8/SVneo. Exposure of HTR-8/SVneo cells for 4 h to 20 ?M BDE-47 increased ROS generation 1.7 fold as measured by the dichlorofluorescein (DCF) assay. Likewise, superoxide anion production increased approximately 5 fold at 10 and 15 ?M and 9 fold at 20 ?M BDE-47 with a 1-h exposure, as measured by cytochrome c reduction. BDE-47 (10, 15 and 20 ?M) decreased the mitochondrial membrane potential by 47–64.5% at 4, 8 and 24 h as assessed with the fluorescent probe Rh123. Treatment with 15 and 20 ?M BDE-47 stimulated cellular release and mRNA expression of IL-6 and IL-8 after 12 and 24-h exposures: the greatest increases were a 35-fold increased mRNA expression at 12 h and a 12-fold increased protein concentration at 24 h for IL-6. Antioxidant treatments (deferoxamine mesylate, (±)?-tocopherol, or tempol) suppressed BDE-47-stimulated IL-6 release by 54.1%, 56.3% and 37.7%, respectively, implicating a role for ROS in the regulation of inflammatory pathways in HTR-8/SVneo cells. Solvent (DMSO) controls exhibited statistically significantly decreased responses compared with non-treated controls for IL-6 release and IL-8 mRNA expression, but these responses were not consistent across experiments and times. Nonetheless, it is possible that DMSO (used to dissolve BDE-47) may have attenuated the stimulatory actions of BDE-47 on cytokine responses. Because abnormal activation of proinflammatory responses can disrupt trophoblast functions necessary for placental development and successful pregnancy, further investigation is warranted of the impact of ROS and BDE-47 on trophoblast cytokine responses. - Highlights: • BDE-47 induced ROS overproduction and mitochondrial dysfunction. • BDE-47 stimulated production of proinflammatory cytokines. • Antioxidant treatment reduced BDE-47-stimulated ROS generation and cytokine release.

  16. Role of reactive oxygen species in arsenic-induced transformation of human lung bronchial epithelial (BEAS-2B) cells

    SciTech Connect (OSTI)

    Zhang, Zhuo; Pratheeshkumar, Poyil; Budhraja, Amit; Son, Young-Ok; Kim, Donghern; Shi, Xianglin

    2015-01-09

    Highlights: • Short term exposure of cells to arsenic causes ROS generation. • Chronical exposure of cells to arsenic causes malignant cell transformation. • Inhibition of ROS generation reduces cell transformation by arsenic. • Arsenic-transformed cells exhibit reduced capacity of generating ROS. • Arsenic-transformed cells exhibit increased levels of antioxidants. - Abstract: Arsenic is an environmental carcinogen, its mechanisms of carcinogenesis remain to be investigated. Reactive oxygen species (ROS) are considered to be important. A previous study (Carpenter et al., 2011) has measured ROS level in human lung bronchial epithelial (BEAS-2B) cells and arsenic-transformed BEAS-2B cells and found that ROS levels were higher in transformed cells than that in parent normal cells. Based on these observations, the authors concluded that cell transformation induced by arsenic is mediated by increased cellular levels of ROS. This conclusion is problematic because this study only measured the basal ROS levels in transformed and parent cells and did not investigate the role of ROS in the process of arsenic-induced cell transformation. The levels of ROS in arsenic-transformed cells represent the result and not the cause of cell transformation. Thus question concerning whether ROS are important in arsenic-induced cell transformation remains to be answered. In the present study, we used expressions of catalase (antioxidant against H{sub 2}O{sub 2}) and superoxide dismutase 2 (SOD2, antioxidant against O{sub 2}{sup ·?}) to decrease ROS level and investigated their role in the process of arsenic-induced cell transformation. Our results show that inhibition of ROS by antioxidant enzymes decreased arsenic-induced cell transformation, demonstrating that ROS are important in this process. We have also shown that in arsenic-transformed cells, ROS generation was lower and levels of antioxidants are higher than those in parent cells, in a disagreement with the previous report. The present study has also shown that the arsenic-transformed cells acquired apoptosis resistance. The inhibition of catalase to increase ROS level restored apoptosis capability of arsenic-transformed BEAS-2B cells, further showing that ROS levels are low in these cells. The apoptosis resistance due to the low ROS levels may increase cells proliferation, providing a favorable environment for tumorigenesis of arsenic-transformed cells.

  17. Generation and reactivity of putative support systems, Ce-Al neutral binary oxide nanoclusters: CO oxidation and C–H bond activation

    SciTech Connect (OSTI)

    Wang, Zhe-Chen; Yin, Shi; Bernstein, Elliot R.

    2013-11-21

    Both ceria (CeO{sub 2}) and alumina (Al{sub 2}O{sub 3}) are very important catalyst support materials. Neutral binary oxide nanoclusters (NBONCs), Ce{sub x}Al{sub y}O{sub z}, are generated and detected in the gas phase and their reactivity with carbon monoxide (CO) and butane (C{sub 4}H{sub 10}) is studied. The very active species CeAlO{sub 4}{sup •} can react with CO and butane via O atom transfer (OAT) and H atom transfer (HAT), respectively. Other Ce{sub x}Al{sub y}O{sub z} NBONCs do not show reactivities toward CO and C{sub 4}H{sub 10}. The structures, as well as the reactivities, of Ce{sub x}Al{sub y}O{sub z} NBONCs are studied theoretically employing density functional theory (DFT) calculations. The ground state CeAlO{sub 4}{sup •} NBONC possesses a kite-shaped structure with an O{sub t}CeO{sub b}O{sub b}AlO{sub t} configuration (O{sub t}, terminal oxygen; O{sub b}, bridging oxygen). An unpaired electron is localized on the O{sub t} atom of the AlO{sub t} moiety rather than the CeO{sub t} moiety: this O{sub t} centered radical moiety plays a very important role for the reactivity of the CeAlO{sub 4}{sup •} NBONC. The reactivities of Ce{sub 2}O{sub 4}, CeAlO{sub 4}{sup •}, and Al{sub 2}O{sub 4} toward CO are compared, emphasizing the importance of a spin-localized terminal oxygen for these reactions. Intramolecular charge distributions do not appear to play a role in the reactivities of these neutral clusters, but could be important for charged isoelectronic BONCs. DFT studies show that the reaction of CeAlO{sub 4}{sup •} with C{sub 4}H{sub 10} to form the CeAlO{sub 4}H•C{sub 4}H{sub 9}{sup •} encounter complex is barrierless. While HAT processes have been previously characterized for cationic and anionic oxide clusters, the reported study is the first observation of a HAT process supported by a ground state neutral oxide cluster. Mechanisms for catalytic oxidation of CO over surfaces of Al{sub x}O{sub y}/M{sub m}O{sub n} or M{sub m}O{sub n}/Al{sub x}O{sub y} materials are proposed consistent with the presented experimental and theoretical results.

  18. Polymer/organosilica nanocomposites based on polyimide with benzimidazole linkages and reactive organoclay containing isoleucine amino acid: Synthesis, characterization and morphology properties

    SciTech Connect (OSTI)

    Mallakpour, Shadpour; Nanotechnology and Advanced Materials Institute, Isfahan University of Technology, Isfahan 84156-83111, Islamic Republic of Iran ; Dinari, Mohammad

    2012-09-15

    Highlights: ? A reactive organoclay was formed using L-isoleucine amino acid as a swelling agent. ? Polyimide was synthesized from benzimidazole diamine and pyromellitic dianhydride. ? Imide and benzimidazole groups assured the thermal stability of the nanocomposites. ? Nanocomposite films were prepared by an in situ polymerization reaction. ? The TEM micrographs of nanocomposites revealed well-exfoliated structures. -- Abstract: Polyimide–silica nanocomposites are attractive hybrid architectures that possess excellent mechanical, thermal and chemical properties. But, the dispersion of inorganic domains in the polymer matrix and the compatibility between the organic and inorganic phases are critical factors in these hybrid systems. In this investigation, a reactive organoclay was prepared via ion exchange reaction between protonated form of difunctional L-isoleucine amino acid as a swelling agent and Cloisite Na{sup +} montmorillonite. Amine functional groups of this swelling agent formed an ionic bond with the negatively charged silicates, whereas the remaining acid functional groups were available for further interaction with polymer chains. Then organo-soluble polyimide (PI) have been successfully synthesized from the reaction of 2-(3,5-diaminophenyl)-benzimidazole and pyromellitic dianhydride in N,N-dimethylacetamide. Finally, PI/organoclay nanocomposite films enclosing 1%, 3%, 5%, 7% and 10% of synthesized organoclay were successfully prepared by an in situ polymerization reaction through thermal imidization. The synthesized hybrid materials were subsequently characterized by Fourier transform infrared spectroscopy, X-ray diffraction, electron microscopy, and thermogravimetric analysis techniques. The PI/organoclay nanocomposite films have good optical transparencies and the mechanical properties were substantially improved by the incorporation of the reactive organoclay.

  19. PLUVIUS: a generalized one-dimensional model of reactive pollutant behavior, including dry deposition, precipitation formation, and wet removal. Second edition

    SciTech Connect (OSTI)

    Easter, R.C.; Hales, J.M.

    1984-11-01

    This report is a second-edition user's manual for the PLUVIUS reactive-storm model. The PLUVIUS code simulates the formation of storm systems of a variety of types, and characterizes the behavior of air pollutants as they flow through, react within, and are scavenged by the storms. The computer code supplied with this report is known as PLUVIUS MOD 5.0, and is a substantial improvement over the MOD 3.1 version given in the original user's manual. Example applications of MOD 5.0 are given in the report to facilitate rapid application of the code for a variety of specific uses. 22 references, 7 figures, 48 tables.

  20. The effect of the composition of plutonium loaded on the reactivity change and the isotopic composition of fuel produced in a fast reactor

    SciTech Connect (OSTI)

    Blandinskiy, V. Yu.

    2014-12-15

    This paper presents the results of a numerical investigation into burnup and breeding of nuclides in metallic fuel consisting of a mixture of plutonium and depleted uranium in a fast reactor with sodium coolant. The feasibility of using plutonium contained in spent nuclear fuel from domestic thermal reactors and weapons-grade plutonium is discussed. It is shown that the largest production of secondary fuel and the least change in the reactivity over the reactor lifetime can be achieved when employing plutonium contained in spent nuclear fuel from a reactor of the RBMK-1000 type.