Sample records for ash impurities consisting

  1. Self-pumping impurity control

    DOE Patents [OSTI]

    Brooks, J.N.; Mattas, R.F.

    1983-12-21T23:59:59.000Z

    It is an object of the present invention to provide an apparatus for removing impurities from the plasma in a fusion reactor without an external vacuum pumping system. It is also an object of the present invention to provide an apparatus for removing the helium ash from a fusion reactor. It is another object of the present invention to provide an apparatus which removes helium ash and minimizes tritium recycling and inventory.

  2. Ash pelletization

    SciTech Connect (OSTI)

    Woodall, M.

    1994-12-31T23:59:59.000Z

    Ash pelletization is outlined under the following topics: projects with CSX involvement; US Generating (Cedar Bay), Jacksonville, FL; Hydra-Co (Salt City Project), Solvay, NY; Virginia Power, Yorktown Plant; US Generating; Indiantown, FL; Future Projects; Development of ash disposal site;s Reuse of ash product; and Utility Survey.

  3. Fluidized bed gasification ash reduction and removal process

    DOE Patents [OSTI]

    Schenone, Carl E. (Madison, PA); Rosinski, Joseph (Vanderbilt, PA)

    1984-12-04T23:59:59.000Z

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  4. Fluidized bed gasification ash reduction and removal system

    DOE Patents [OSTI]

    Schenone, Carl E. (Madison, PA); Rosinski, Joseph (Vanderbilt, PA)

    1984-02-28T23:59:59.000Z

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  5. Coulomb impurity in graphene

    E-Print Network [OSTI]

    Rudro R. Biswas; Subir Sachdev; Dam T. Son

    2007-11-29T23:59:59.000Z

    We consider the problem of screening of an electrically charged impurity in a clean graphene sheet. When electron-electron interactions are neglected, the screening charge has a sign opposite to that of the impurity, and is localized near the impurity. Interactions between electrons smear out the induced charge density to give a large-distance tail that follows approximately, but not exactly, an r^{-2} behavior and with a sign which is the same as that of the impurity.

  6. Activation of fly ash

    DOE Patents [OSTI]

    Corbin, D.R.; Velenyi, L.J.; Pepera, M.A.; Dolhyj, S.R.

    1986-08-19T23:59:59.000Z

    Fly ash is activated by heating a screened magnetic fraction of the ash in a steam atmosphere and then reducing, oxidizing and again reducing the hydrothermally treated fraction. The activated fly ash can be used as a carbon monoxide disproportionating catalyst useful in the production of hydrogen and methane.

  7. Activation of fly ash

    DOE Patents [OSTI]

    Corbin, David R. (New Castle, DE); Velenyi, Louis J. (Lyndhurst, OH); Pepera, Marc A. (Northfield, OH); Dolhyj, Serge R. (Parma, OH)

    1986-01-01T23:59:59.000Z

    Fly ash is activated by heating a screened magnetic fraction of the ash in a steam atmosphere and then reducing, oxidizing and again reducing the hydrothermally treated fraction. The activated fly ash can be used as a carbon monoxide disproportionating catalyst useful in the production of hydrogen and methane.

  8. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-06-20T23:59:59.000Z

    A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device is disclosed. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500 C to about 700 C for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal. 1 fig.

  9. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO)

    1995-01-01T23:59:59.000Z

    A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500.degree. C. to about 700.degree. C. for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal.

  10. Fly ash carbon passivation

    DOE Patents [OSTI]

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14T23:59:59.000Z

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  11. High power light emitting diode based setup for photobleaching fluorescent impurities

    E-Print Network [OSTI]

    Kaufman, Laura

    High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes

  12. The rp Process Ashes from Stable Nuclear Burning on an Accreting Neutron Star

    E-Print Network [OSTI]

    Hendrik Schatz; Lars Bildsten; Andrew Cumming; Michael Wiescher

    1999-05-20T23:59:59.000Z

    We calculate the nucleosynthesis during stable nuclear burning on an accreting neutron star. This is appropriate for weakly magnetic neutron stars accreting at near-Eddington rates in low mass X-ray binaries, and for most accreting X-ray pulsars. We show that the nuclear burning proceeds via the rapid proton capture process (rp process), and makes nuclei far beyond the iron group. The final mixture of nuclei consists of elements with a range of masses between approximately A=60 and A=100. The average nuclear mass of the ashes is set by the extent of helium burning via (alpha,p) reactions, and depends on the local accretion rate. Our results imply that the crust of these accreting neutron stars is made from a complex mixture of heavy nuclei, with important implications for its thermal, electrical and structural properties. A crustal lattice as impure as our results suggest will have a conductivity set mostly by impurity scattering, allowing more rapid Ohmic diffusion of magnetic fields than previously estimated.

  13. State Waste Discharge Permit application: 200-E Powerhouse Ash Pit

    SciTech Connect (OSTI)

    Atencio, B.P.

    1994-06-01T23:59:59.000Z

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department and Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-E Powerhouse Ash Pit. The 200-E Powerhouse Ash Waste Water discharges to the 200-E Powerhouse Ash Pit via dedicated pipelines. The 200-E Ash Waste Water is the only discharge to the 200-E Powerhouse Ash Pit. The 200-E Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  14. State Waste Discharge Permit application: 200-W Powerhouse Ash Pit

    SciTech Connect (OSTI)

    Atencio, B.P.

    1994-06-01T23:59:59.000Z

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations; the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-W Powerhouse Ash Pit. The 200-W Powerhouse Ash Waste Water discharges to the 200-W Powerhouse Ash Pit via dedicated pipelines. The 200-W Powerhouse Ash Waste Water is the only discharge to the 200-W Powerhouse Ash Pit. The 200-W Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  15. Ashing properties of coal blends

    SciTech Connect (OSTI)

    Biggs, D.L.

    1982-03-01T23:59:59.000Z

    The fusion properties of sulfur materials present in coals were investigated. The treatment of the samples of eleven different coals is described. Thermal treatment of low temperature ashing (LTA) concentrates of eight of the coals was performed, and raw and wash ashing curves were examined to determine what quantitative correlations, if any, exist between ashing parameters and rank of coal. The actual form of the function which describes the ashing curve is derived.

  16. Screening technology reduces ash in spiral circuits

    SciTech Connect (OSTI)

    Brodzik, P. [Derrick Corp., Buffalo, NY (United States)

    2007-05-15T23:59:59.000Z

    In 2006, the James River Coal Co. selected the Stack Sizer to remove the minus 100 mesh high ash clay fraction from the clean coal spiral product circuits at the McCoy-Elkhorn Bevins Branch prep plant and at the Blue Diamond Leatherwood prep plant in Kentucky. The Stack Sizer is a multi-deck, high-frequency vibrating screen capable of separations as fine as 75 microns when fitted with Derrick Corp.'s patented high open area urethane screen panels. Full-scale lab tests and more than 10 months of continuous production have confirmed that the Stack Sizer fitted with Derrick 100 micron urethane screen panels consistently produces a clean coal fraction that ranges from 8 to 10% ash. Currently, each five-deck Stack Sizer operating at the Bevins Branch and Leatherwood prep plants is producing approximately 33 tons per hour of clean coal containing about 9% ash. This represents a clean coal yield of about 75% and an ash reduction of about 11% from the feed slurry. 3 figs. 2 tabs.

  17. Impurity gettering in silicon using cavities formed by helium implantation and annealing

    DOE Patents [OSTI]

    Myers, Jr., Samuel M. (Albuquerque, NM); Bishop, Dawn M. (Albuquerque, NM); Follstaedt, David M. (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    Impurity gettering in silicon wafers is achieved by a new process consisting of helium ion implantation followed by annealing. This treatment creates cavities whose internal surfaces are highly chemically reactive due to the presence of numerous silicon dangling bonds. For two representative transition-metal impurities, copper and nickel, the binding energies at cavities were demonstrated to be larger than the binding energies in precipitates of metal silicide, which constitutes the basis of most current impurity gettering. As a result the residual concentration of such impurities after cavity gettering is smaller by several orders of magnitude than after precipitation gettering. Additionally, cavity gettering is effective regardless of the starting impurity concentration in the wafer, whereas precipitation gettering ceases when the impurity concentration reaches a characteristic solubility determined by the equilibrium phase diagram of the silicon-metal system. The strong cavity gettering was shown to induce dissolution of metal-silicide particles from the opposite side of a wafer.

  18. Impurity gettering in silicon using cavities formed by helium implantation and annealing

    DOE Patents [OSTI]

    Myers, S.M. Jr.; Bishop, D.M.; Follstaedt, D.M.

    1998-11-24T23:59:59.000Z

    Impurity gettering in silicon wafers is achieved by a new process consisting of helium ion implantation followed by annealing. This treatment creates cavities whose internal surfaces are highly chemically reactive due to the presence of numerous silicon dangling bonds. For two representative transition-metal impurities, copper and nickel, the binding energies at cavities were demonstrated to be larger than the binding energies in precipitates of metal silicide, which constitutes the basis of most current impurity gettering. As a result the residual concentration of such impurities after cavity gettering is smaller by several orders of magnitude than after precipitation gettering. Additionally, cavity gettering is effective regardless of the starting impurity concentration in the wafer, whereas precipitation gettering ceases when the impurity concentration reaches a characteristic solubility determined by the equilibrium phase diagram of the silicon-metal system. The strong cavity gettering was shown to induce dissolution of metal-silicide particles from the opposite side of a wafer. 4 figs.

  19. Coal ash utilization in India

    SciTech Connect (OSTI)

    Michalski, S.R.; Brendel, G.F.; Gray, R.E. [GAI Consultants, Inc., Pittsburgh, PA (United States)

    1998-12-31T23:59:59.000Z

    This paper describes methods of coal combustion product (CCP) management successfully employed in the US and considers their potential application in India. India produces about 66 million tons per year (mty) of coal ash from the combustion of 220 mty of domestically produced coal, the average ash content being about 30--40 percent as opposed to an average ash content of less than 10 percent in the US In other words, India produces coal ash at about triple the rate of the US. Currently, 95 percent of this ash is sluiced into slurry ponds, many located near urban centers and consuming vast areas of premium land. Indian coal-fired generating capacity is expected to triple in the next ten years, which will dramatically increase ash production. Advanced coal cleaning technology may help reduce this amount, but not significantly. Currently India utilizes two percent of the CCP`s produced with the remainder being disposed of primarily in large impoundments. The US utilizes about 25 percent of its coal ash with the remainder primarily being disposed of in nearly equal amounts between dry landfills and impoundments. There is an urgent need for India to improve its ash management practice and to develop efficient and environmentally sound disposal procedures as well as high volume ash uses in ash haulback to the coalfields. In addition, utilization should include: reclamation, structural fill, flowable backfill and road base.

  20. E-Print Network 3.0 - ash bottom ash Sample Search Results

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

    Summary: of bottom ash, 3 million tons of boiler slag, and 28 million tons of clean-coal ash materials) were produced... CONTAINING CLEAN-COAL ASH AND CLASS F FLY ASH By...

  1. Modeling volcanic ash dispersal

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    Explosive volcanic eruptions inject into the atmosphere large amounts of volcanic material (ash, blocks and lapilli). Blocks and larger lapilli follow ballistic and non-ballistic trajectories and fall rapidly close to the volcano. In contrast, very fine ashes can remain entrapped in the atmosphere for months to years, and may affect the global climate in the case of large eruptions. Particles having sizes between these two end-members remain airborne from hours to days and can cover wide areas downwind. Such volcanic fallout entails a serious threat to aircraft safety and can create many undesirable effects to the communities located around the volcano. The assessment of volcanic fallout hazard is an important scientific, economic, and political issue, especially in densely populated areas. From a scientific point of view, considerable progress has been made during the last two decades through the use of increasingly powerful computational models and capabilities. Nowadays, models are used to quantify hazard scenarios and/or to give short-term forecasts during emergency situations. This talk will be focused on the main aspects related to modeling volcanic ash dispersal and fallout with application to the well known problem created by the Eyjafjöll volcano in Iceland. Moreover, a short description of the main volcanic monitoring techniques is presented.

  2. Optical properties of fly ash. Volume 2, Final report

    SciTech Connect (OSTI)

    Self, S.A.

    1994-12-01T23:59:59.000Z

    Research performed under this contract was divided into four tasks under the following headings: Task 1, Characterization of fly ash; Task 2, Measurements of the optical constants of slags; Task 3, Calculations of the radiant properties of fly ash dispersions; and Task 4, Measurements of the radiant properties of fly ash dispersions. Tasks 1 and 4 constituted the Ph.D. research topic of Sarbajit Ghosal, while Tasks 2 and 3 constituted the Ph.D. research topic of Jon Ebert. Together their doctoral dissertations give a complete account of the work performed. This final report, issued in two volumes consists of an executive summary of the whole program followed by the dissertation of Ghosal and Ebert. Volume 2 contains the dissertation of Ebert which covers the measurements of the optical constants of slags, and calculations of the radiant properties of fly ash dispersions. A list of publications and conference presentations resulting from the work is also included.

  3. Ash deposit workshop: Class outline

    SciTech Connect (OSTI)

    Hatt, R. [Commercial Testing & Engineering Co., Lexington, KY (United States)

    1996-12-31T23:59:59.000Z

    Ash deposits formed from the combustion of coal and other fuels have plagued the steam production industry from the start. The ash fusion test has been around for over eighty years. As steam plant size increased, so have the problems associated with ash deposits. This workshop is designed to cover: (1) The basic types of deposits. (2) Causes of deposits. (3) Analytical procedures for resolving, or at least providing information about deposits and fuels, and (4) Deposit removal and reduction techniques.

  4. SEPARATION OF PROTEINS BY ION EXCHANGE AND MEMBRANE CHROMATOGRAPHY: BUFFER COMPOSITION, INTERFERING IMPURITIES AND FOULING CONSIDERATIONS

    E-Print Network [OSTI]

    Imam, Tahmina

    2010-01-16T23:59:59.000Z

    on identifying major impurity and optimization of solution properties for target protein purification. The second approach consisted of designing an adsorbent that interacted specifically with the target molecule. The first study included modification of protein...

  5. Control of impurities in toroidal plasma devices

    DOE Patents [OSTI]

    Ohkawa, Tihiro (La Jolla, CA)

    1980-01-01T23:59:59.000Z

    A method and apparatus for plasma impurity control in closed flux plasma systems such as Tokamak reactors is disclosed. Local axisymmetrical injection of hydrogen gas is employed to reverse the normally inward flow of impurities into the plasma.

  6. Stabilize ash using Clemson`s sintering process (Part 1 -- Phase 1 results): Mixed waste fly ash stabilization. Innovative technology summary report

    SciTech Connect (OSTI)

    Not Available

    1998-12-01T23:59:59.000Z

    Incineration of applicable Department of Energy (DOE) mixed wastes has produced a secondary waste stream of radioactive and Resource Conservation and Recovery Act (RCRA) hazardous fly ash that also requires treatment before land disposal. Unlike bottom ash, fly ash usually contains constituents making efficient stabilization difficult. For example, fly ash from the DOE Waste Experimental Reduction Facility (WERF) incinerator at the Idaho National Engineering and Environmental Laboratory (INEEL) contains volatile metals, metal salts, high concentrations of zinc, and unburned organic residues. All of these constituents can effect the stabilization process. The Department of Energy, and in particular the Mixed Waste Focus Area (MWFA) of EM-50, has stated the need for improved stabilization methods would accept a higher ash waste loading while meeting waste form disposal criteria. These alternative stabilization technologies should include delivery systems to minimize worker exposure and minimize secondary waste generation, while maximizing operational flexibility and radionuclide containment. Currently, the standard practice for stabilizing ash is mixing with Portland cement at room temperature. This standard practice produces a significant increase of waste material volume or has difficulty in adequately stabilizing the components in the fly ash to ensure regulatory requirements are consistently satisfied. To address these fly ash stabilization shortcomings, the MWFA, a DOE/EM-50 program, invested in the development of several fly ash stabilization alternatives, including the Clemson University sintering method.

  7. Impact of Biodiesel Impurities on the Performance and Durability of DOC, DPF and SCR Technologies: Preprint

    SciTech Connect (OSTI)

    Williams, A.; McCormick, R.; Luecke, J.; Brezny, R.; Geisselmann, A.; Voss, K.; Hallstrom, K.; Leustek, M.; Parsons, J.; Abi-Akar, H.

    2011-04-01T23:59:59.000Z

    An accelerated durability test method determined the potential impact of biodiesel ash impurities, including engine testing with multiple diesel particulate filter substrate types, as well as diesel oxidation catalyst and selective catalyst reduction catalysts. The results showed no significant degradation in the thermo-mechanical properties of a DPF after exposure to 150,000-mile equivalent biodiesel ash and thermal aging. However, exposure to 435,000-mile equivalent aging resulted in a 69% decrease in thermal shock resistance. A decrease in DOC activity was seen after exposure to 150,000-mile equivalent aging, resulting in higher hydrocarbon slip and a reduction in NO2 formation. The SCR catalyst experienced a slight loss in activity after exposure to 435,000-mile equivalent aging. The SCR catalyst, placed downstream of the DPF and exposed to B20 exhaust suffered a 5% reduction in overall NOx conversion activity over the HDDT test cycle. It is estimated that the additional ash from 150,000 miles of biodiesel use would also result in a moderate increases in exhaust backpressure for a DPF. The results of this study suggest that long-term operation with B20 at the current specification limits for alkali and alkaline earth metal impurities will adversely impact the performance of DOC, DPF and SCR systems.

  8. Self-pumping impurity control

    DOE Patents [OSTI]

    Brooks, Jeffrey N. (Darien, IL); Mattas, Richard F. (Downers Grove, IL)

    1991-01-01T23:59:59.000Z

    Apparatus for removing the helium ash from a fusion reactor having a D-T plasma comprises a helium trapping site within the reactor plasma confinement device, said trapping site being formed of a trapping material having negligible helium solubility and relatively high hydrogen solubility; and means for depositing said trapping material on said site at a rate sufficient to prevent saturation of helium trapping.

  9. Long duration ash probe

    DOE Patents [OSTI]

    Hurley, J.P.; McCollor, D.P.; Selle, S.J.

    1994-07-26T23:59:59.000Z

    A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during soot blowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon. 8 figs.

  10. Long duration ash probe

    DOE Patents [OSTI]

    Hurley, John P. (Grand Forks, ND); McCollor, Don P. (Grand Forks, ND); Selle, Stanley J. (Grand Forks, MN)

    1994-01-01T23:59:59.000Z

    A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during sootblowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon.

  11. Engineering Metal Impurities in Multicrystalline Silicon Solar...

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

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar...

  12. Impact of Biodiesel Impurities on the Performance and Durability of DOC, DPF and SCR Technologies

    SciTech Connect (OSTI)

    Williams, A.; McCormick, R.; Luecke, J.; Brezny, R.; Geisselmann, A.; Voss, K.; Hallstrom, K.; Leustek, M.; Parsons, J.; Abi-Akar, H.

    2011-06-01T23:59:59.000Z

    It is estimated that operating continuously on a B20 fuel containing the current allowable ASTM specification limits for metal impurities in biodiesel could result in a doubling of ash exposure relative to lube-oil derived ash. The purpose of this study was to determine if a fuel containing metals at the ASTM limits could cause adverse impacts on the performance and durability of diesel emission control systems. An accelerated durability test method was developed to determine the potential impact of these biodiesel impurities. The test program included engine testing with multiple DPF substrate types as well as DOC and SCR catalysts. The results showed no significant degradation in the thermo-mechanical properties of cordierite, aluminum titanate, or silicon carbide DPFs after exposure to 150,000 mile equivalent biodiesel ash and thermal aging. However, exposure of a cordierite DPF to 435,000 mile equivalent aging resulted in a 69% decrease in the thermal shock resistance parameter. It is estimated that the additional ash from 150,000 miles of biodiesel use would also result in a moderate increases in exhaust backpressure for a DPF. A decrease in DOC activity was seen after exposure to 150,000 mile equivalent aging, resulting in higher HC slip and a reduction in NO{sub 2} formation. The metal-zeolite SCR catalyst experienced a slight loss in activity after exposure to 435,000 mile equivalent aging. This catalyst, placed downstream of the DPF, showed a 5% reduction in overall NOx conversion activity over the HDDT test cycle.

  13. ash dispersion utilizing: Topics by E-print Network

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

    in the USA for all coal ashes was approximately 34% in the year products containing clean coal ash compared to conventional coal ash. Utilization of clean coal ash is much...

  14. Speciation of Selenium, Arsenic, and Zinc in Class C Fly Ash

    SciTech Connect (OSTI)

    Luo, Yun; Giammar, Daniel E.; Huhmann, Brittany L.; Catalano, Jeffrey G. (WU)

    2011-11-17T23:59:59.000Z

    A major environmental concern associated with coal fly ash is the mobilization of trace elements that may contaminate water. To better evaluate proper use of fly ash, determine appropriate disposal methods, and monitor postdisposal conditions, it is important to understand the speciation of trace elements in fly ash and their possible environmental impact. The speciation of selenium, arsenic, and zinc was determined in five representative Class C fly ash samples from combustion of sub-bituminous Powder River Basin coal using synchrotron-based X-ray absorption spectroscopy to provide an improved understanding of the mechanisms of trace element association with the fly ash. Selenium in all fly ash samples occurs predominantly as Se(IV), with the exception of one sample, in which there was a minor amount of Se(0). Se(0) is likely associated with the high content of unburned coal in the sample. Arsenic exists in the fly ash as a single phase most consistent with calcium pyroarsenate. In contrast, zinc occurs as two distinct species in the silicate glass matrix of the fly ash. This work demonstrates that residual carbon in fly ash may reduce potential Se mobility in the environment by retaining it as less soluble elemental Se instead of Se(IV). Further, this work suggests that As and Zn in Class C fly ash will display substantially different release and mobilization behaviors in aquatic environments. While As release will primarily depend upon the dissolution and hydrolysis of calcium pyroarsenate, Zn release will be controlled by the dissolution of alkaline aluminosilicate glass in the ash.

  15. Effect of Impurities Scattering Potential on NMR relaxation rate in impure d-wave superconductors

    E-Print Network [OSTI]

    P. Udomsamuthirun; K. Meemon

    2009-07-20T23:59:59.000Z

    The purpose of our research is to study the nuclear spin lattice relaxation rate of impure d-wave superconductors. We use the Green function method to derive the approximation equation of density of states including the impurity scattering potential. We can get the analytic equation of the nuclear spin lattice relaxation rate that contained the impurity scattering potential in case of weak scattering potential and strong scattering potential in the simple form as the power series of order parameter and temperature . The numerical calculations show that there is coherence peak in the weak impurity scattering potential but there is no peak in the strong impurity scattering potential.

  16. Journal of Hazardous Materials B132 (2006) 244252 Zeolite synthesis from paper sludge ash at low temperature

    E-Print Network [OSTI]

    Downs, Robert T.

    2006-01-01T23:59:59.000Z

    Journal of Hazardous Materials B132 (2006) 244­252 Zeolite synthesis from paper sludge ash at low consists of organic fibers, inorganic clay-sized materials, and about 60% water, and is incinerated and 9. Alternative processing methods of zeolite synthesis, including the addition of ash

  17. Innovative technologies for impurity control

    SciTech Connect (OSTI)

    Nygren, R.E. (ed.)

    1992-03-01T23:59:59.000Z

    A brief discussion of the following topics is given in this report: Liquid Metal Divertors; Lithium Droplet Beam Divertor; Preferential Pumping of Helium; Reduced Erosion with Cu-Li, W-Li, etc.; Reduction of Erosion by Thermionic Emission; Reduced Erosion in Boronized Graphites; Proposal for Materials Experiments in TRIAM; Carbon-SiC for Plasma Facing Components; Helium Pumping with Palladium; Large Area Pump Limiter; Techniques for Enhanced Heat Removal; New Outlook on Gaseous Divertors; Gaseous Divertor Simulations; Impurity Seeding to Control ITER Particle and Heat Loads; Gaseous Divertor Experiments; Electrical Biasing to Control SOL Particle Fluxes; Biased Limiter in TEXTOR and Biased Divertor in PBX-M; Particle and Heat Flux Control Using Ponderomotive Forces; Helium Exhaust Using ICRF; Ergodic Magnetic Limiter Experiments in JFT-2M; and Helium Exhaust Using Fishbones.

  18. Advanced Characterisation of Municipal Solid Waste Ashes

    E-Print Network [OSTI]

    Advanced Characterisation of Municipal Solid Waste Ashes Preparatory thesis Randi Skytte Pedersen is to investigate Municipal Solid Waste (MSW) ashes with respect to particle sizes, structures and composition with characterisation of Municipal Solid Waste (MSW) ashes from the Danish power plant M°abjergværket, Holstebro. MSW

  19. Interaction of coal-derived synthesis gas impurities with solid...

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

    coal-derived synthesis gas impurities with solid oxide fuel cell metallic components. Interaction of coal-derived synthesis gas impurities with solid oxide fuel cell metallic...

  20. Petrographic characterization of economizer fly ash

    SciTech Connect (OSTI)

    Valentim, B.; Hower, J.C.; Soares, S.; Guedes, A.; Garcia, C.; Flores, D.; Oliveira, A. [University of Porto, Oporto (Portugal). Center of Geology

    2009-11-15T23:59:59.000Z

    Policies for reducing NOx emissions have led power plants to restrict O{sub 2}, resulting in high-carbon fly ash production. Therefore, some potentially useful fly ash, such as the economizer fly ash, is discarded without a thorough knowledge of its composition. In order to characterize this type of fly ash, samples were collected from the economizer Portuguese power plant burning two low-sulfur bituminous coals. Characterization was also performed on economizer fly ash subsamples after wet sieving, density and magnetic separation. Analysis included atomic absorption spectroscopy, loss-on-ignition, scanning electron microscopy/energy-dispersive X-ray spectroscopy, optical microscopy, and micro-Raman spectroscopy.

  1. ACAA fly ash basics: quick reference card

    SciTech Connect (OSTI)

    NONE

    2006-07-01T23:59:59.000Z

    Fly ash is a fine powdery material created when coal is burned to generate electricity. Before escaping into the environment via the utility stacks, the ash is collected and may be stored for beneficial uses or disposed of, if necessary. The use of fly ash provides environmental benefits, such as the conservation of natural resources, the reduction of greenhouse gas emissions and eliminating the needed for ash disposal in landfills. It is also a valuable mineral resource that is used in construction and manufacturing. Fly ash is used in the production of Portland cement, concrete, mortars and stuccos, manufactured aggregates along with various agricultural applications. As mineral filler, fly ash can be used for paints, shingles, carpet backing, plastics, metal castings and other purposes. This quick reference card is intended to provide the reader basic source, identification and composition, information specifically related to fly ash.

  2. The reactions and ashes of thermonuclear explosions on neutron stars

    E-Print Network [OSTI]

    J. L. Fisker; E. Brown; M. Liebendoerfer; F. -K. Thielemann; M. Wiescher

    2004-08-04T23:59:59.000Z

    This paper reports on the detailed rp-process reaction flow on an accreting neutron star and the resulting ashes of a type I X-ray burst. It is obtained by coupling a 298 isotope reaction network to a self-consistent one-dimensional model calculation with a constant accretion rate of dM/dt=1.0e17g/s (0.09 Eddington).

  3. Overview of SOFC Anode Interactions with Coal Gas Impurities

    SciTech Connect (OSTI)

    Marina, Olga A.; Pederson, Larry R.; Gemmen, Randall; Gerdes, Kirk; Finklea, Harry; Celik, Ismail B.

    2009-08-11T23:59:59.000Z

    Efficiencies greater than 50 percent (higher heating value) have been projected for solid oxide fuel cell (SOFC) systems fueled with gasified coal, even with carbon sequestration. Multiple minor and trace components are present in coal that could affect fuel cell performance, however, which vary widely depending on coal origin and type. Minor and trace components have been classified into three groups: elements with low volatility that are likely to remain in the ash, elements that will partition between solid and gas phases, and highly volatile elements that are unlikely to condense. Those in the second group are of most concern. In the following, an overview of the results of SOFC anode interactions with phosphorus, arsenic, selenium, sulfur, antimony, and hydrogen chloride as single contaminants or in combinations is discussed. Tests were performed using both anode- and electrolyte-supported cells in synthetic coal gas. The ultimate purpose of this work is to establish maximum permissible concentrations for impurities in coal gas, to aid in the selection of appropriate coal gas clean-up technologies.

  4. Impurity radiation from a tokamak plasma

    SciTech Connect (OSTI)

    Morozov, D. Kh.; Baronova, E. O. [Russian Research Centre Kurchatov Institute, Nuclear Fusion Institute (Russian Federation); Senichenkov, I. Yu. [St. Petersburg State Polytechnical University (Russian Federation)

    2007-11-15T23:59:59.000Z

    In tokamak operating modes, energy balance is often governed by impurity radiation. This is the case near the divertor plates, during impurity pellet injection, during controlled discharge disruptions, etc. The calculation of impurity radiation is a fairly involved task (it is sometimes the most difficult part of the general problem) because the radiation power is determined by the distribution of ions over the excited states and by the rate constants of elementary processes of radiation and absorption. The objective of this paper is to summarize in one place all the approximate formulas that would help investigators to describe radiation from the most often encountered impurities in a fairly simple way in their calculations accounting for plasma radiation, without reference to special literature. Simple approximating formulas describing ionization, recombination, and charge-exchange processes, as well as radiative losses from ions with a given charge, are presented for five impurity species: beryllium, carbon, oxygen, neon, and argon. Estimating formulas that allow one to take into account plasma opacity for resonant photons in line impurity radiation are also presented.

  5. Characterization of ash residues from 15 waste-to-energy facilities pursuant to the May, 1994 U.S. EPA ``Sampling and analysis of municipal refuse incineration ash`` guidance document

    SciTech Connect (OSTI)

    Berry, J.; Lyons, M. [Wheelabrator Environmental Systems Inc., Hampton, NH (United States)

    1996-12-31T23:59:59.000Z

    Wheelabrator Environmental Systems Inc. (Wheelabrator) currently owns and/or operates 21 power plants, 15 of which are municipal waste combustion (MWC) facilities. In response to a May, 1994 US Supreme Court decision, all MWC facilities are required by the US Environmental Protection (EPA) to determine if the facility ash residues are hazardous waste. This paper presents the results of ash characterizations done at Wheelabrator MWC facilities. All Wheelabrator MWC facilities are equipped with WES-PHix{reg_sign} ash stabilization systems. The ash from these facilities consistently yields test results well below regulatory thresholds. However, installing a state-of-the-art ash stabilization system does not guarantee that ash is accurately characterized. Proper sampling protocols and proper analytical technique are critical to insuring accurate characterization. This paper identifies typical issues encountered during sample collection, sample preparation, an toxicity test extraction procedures. The consistently low toxicity test results for ash from Wheelabrator facilities can be attributed to the effectiveness of the WES-PHix{reg_sign} ash stabilization process. The sample collection protocols developed by Wheelabrator, and proper toxicity test extraction and analytical procedures followed by the laboratories, ensure accurate characterization.

  6. Combustion with reduced carbon in the ash

    DOE Patents [OSTI]

    Kobayashi, Hisashi; Bool, III, Lawrence E.

    2005-12-27T23:59:59.000Z

    Combustion of coal in which oxygen is injected into the coal as it emerges from burner produces ash having reduced amounts of carbon.

  7. ash leachate generation: Topics by E-print Network

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

    72 Key To Ash Sources FGD-1 MPU 8 Materials Science Websites Summary: Key To Ash Sources FGD-1 MPU 8 FGD-2 Alliant Energy FGD-3 WPS Pulliam Ash 12;Center for By-Products...

  8. ash quality characterization: Topics by E-print Network

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

    78 Key To Ash Sources FGD-1 MPU 8 Materials Science Websites Summary: Key To Ash Sources FGD-1 MPU 8 FGD-2 Alliant Energy FGD-3 WPS Pulliam Ash 12;Center for By-Products...

  9. Treatment of fly ash for use in concrete

    DOE Patents [OSTI]

    Boxley, Chett (Park City, UT)

    2012-05-15T23:59:59.000Z

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with a quantity of spray dryer ash (SDA) and water to initiate a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 40%, and in some cases less than 20%, of the foam index of the untreated fly ash. An optional alkaline activator may be mixed with the fly ash and SDA to facilitate the geopolymerization reaction. The alkaline activator may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  10. ash blended cement: Topics by E-print Network

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

    biomass blends Texas A&M University - TxSpace Summary: , low ash partially composted manure LAPC, high ash raw manure HARM, and high ash partially composted manure HAPC)...

  11. Development of dredged ash disposal area, Paradise fossil plant

    SciTech Connect (OSTI)

    Not Available

    1989-02-01T23:59:59.000Z

    Paradise Steam-Electric Plant coal-fired facility in Muhlenberg County, Kentucky. This project is to construct a dredge pond near the Jacobs Creek ash pond capable of storing fly ash dredged from the ash pond. This will provide approximately 10 years of additional fly ash storage in the fly ash pond. Effluent from the dredge pond will be returned to the Jacobs Creek ash pond for discharge to Jacobs Creek. 4 figs., 5 tabs.

  12. ashes oral biotillgaenglighet: Topics by E-print Network

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

    ash 1. Halima Hadiahmetovi?; D. D. Sarajevo; M. Sc; Raza Sunulahpai?; Bosnia Herzegovina 97 Leachate Geochemical Results for Ash Samples from the June 2007 Angora...

  13. Development of an Accelerated Ash-Loading Protocol for Diesel...

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

    an Accelerated Ash-Loading Protocol for Diesel Particulate Filters Development of an Accelerated Ash-Loading Protocol for Diesel Particulate Filters Poster presentation at the 2007...

  14. Ashe County - Wind Energy System Ordinance | Department of Energy

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

    Tribal Government Utility Program Info State North Carolina Program Type SolarWind Permitting Standards Provider Ashe County Planning Department In 2007 Ashe County...

  15. Impact of Biodiesel on Ash Emissions and Lubricant Properties...

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

    Biodiesel on Ash Emissions and Lubricant Properties Affecting Fuel Economy and Engine Wear Impact of Biodiesel on Ash Emissions and Lubricant Properties Affecting Fuel Economy and...

  16. ash intranasal instillation: Topics by E-print Network

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

    there is no mixing of insufficiently thermally treated material with bottom ash. Good fire control Columbia University 17 Characteristics and Uses for Ash Environmental...

  17. ash deposition propensities: Topics by E-print Network

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

    Environments (>3.5 km), banded iron, volcanic ashes Summary diagrams available Clastic depositional environments Harbor, David 57 Ash Dump Site Manager: EHS&RM Biology and...

  18. Uncovering Fundamental Ash-Formation Mechanisms and Potential...

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

    Analysis of Ash Formation and Transport Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy Non-Destructive X-ray Measurement of Soot, Ash,...

  19. Minimizing Lubricant-Ash Requirement and Impact on Emission Aftertreat...

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

    Minimizing Lubricant-Ash Requirement and Impact on Emission Aftertreatment Systems via an Oil Conditioning Filter Minimizing Lubricant-Ash Requirement and Impact on Emission...

  20. Impurity effect in a holographic superconductor

    E-Print Network [OSTI]

    Takaaki Ishii; Sang-Jin Sin

    2013-01-30T23:59:59.000Z

    We consider a holographic superconductor with homogeneous impurities added. We start with the holographic Abelian-Higgs model for s-wave superconductivity, and turn on a coupling between the gauge field and a new massive gauge field that is introduced for impurities, whose effect is examined in the probe limit. We find that the condensation of the massive gauge field is induced in the superconducting phase. When the coupling is sufficiently large, the mass gap in the optical conductivity disappears. A resonance peak is found in the conductivity for the massive vector field.

  1. Ash Chemistry in MSW Incineration Plants

    E-Print Network [OSTI]

    Ash Chemistry in MSW Incineration Plants: Advanced Characterization and Thermodynamic Introduction to Municipal Solid Waste Incineration 2 Chapter 2 Plants Considered and Samples Collected 5 Chapter 3 Mapping of Ash Chemistry in MSWI Plants 8 Chapter 4 Advanced Characterization Methods 12 4

  2. Photoluminescence and photostimulated luminescence of oxygen impurities in CsBr

    SciTech Connect (OSTI)

    Appleby, G. A.; Zimmermann, J.; Hesse, S.; Seggern, H. von [Electronic Materials Division, Institute of Materials Science, Darmstadt University of Technology, 64287 Darmstadt (Germany)

    2011-01-01T23:59:59.000Z

    Oxygen impurities have been detected in undoped CsBr by photoluminescence (PL) spectroscopy and their contribution to photostimulated luminescence (PSL) properties of powdered CsBr is discussed. When excited at 200 nm, PL is observed from CsBr which consists of three separate emission peaks. The intrinsic luminescence of CsBr at 379 nm is accompanied by two emission peaks at 395 and 460 nm which arise from oxygen impurities, the latter of which is also PSL active following x-irradiation. Sintering of CsBr with the reducing agent NH{sub 4}Br removes the oxygen impurities so that the 395 and 460 nm emissions are no longer detectable, and subsequently the PSL emission is significantly reduced. PSL storage time measurements of these materials show that oxygen impurities favorably increase both the PSL sensitivity and radiation induced charge-center stability in CsBr:Eu{sup 2+}. The oxygen impurities and their associated luminescence properties can be reintroduced to the CsBr matrix with a controlled concentration by doping with CsOH and then subsequently sintering the resultant CsBr:OH{sup -} with NH{sub 4}Br, which in this system reduces the OH{sup -} centers to O{sup 2-}.

  3. Fly Ash Amendments Catalyze Soil Carbon Sequestration

    SciTech Connect (OSTI)

    Amonette, James E.; Kim, Jungbae; Russell, Colleen K.; Palumbo, A. V.; Daniels, William L.

    2003-09-15T23:59:59.000Z

    We tested the effects of four alkaline fly ashes {Class C (sub-bituminous), Class F (bituminous), Class F [bituminous with flue-gas desulfurization (FGD) products], and Class F (lignitic)} on a reaction that simulates the enzyme-mediated formation of humic materials in soils. The presence of FGD products completely halted the reaction, and the bituminous ash showed no benefit over an ash-free control. The sub-bituminous and lignitic fly ashes, however, increased the amount of polymer formed by several-fold. The strong synergetic effect of these ashes when enzyme is present apparently arises from the combined effects of metal oxide co-oxidation (Fe and Mn oxides), alkaline pH, and physical stabilization of the enzyme (porous silica cenospheres).

  4. Treatment of fly ash for use in concrete

    SciTech Connect (OSTI)

    Boxley, Chett; Akash, Akash; Zhao, Qiang

    2013-01-08T23:59:59.000Z

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  5. Treatment of fly ash for use in concrete

    DOE Patents [OSTI]

    Boxley, Chett (Park City, UT); Akash, Akash (Salt lake City, UT); Zhao, Qiang (Natick, MA)

    2012-05-08T23:59:59.000Z

    A process for treating fly ash to render it highly usable as a concrete additive. A quantity of fly ash is obtained that contains carbon and which is considered unusable fly ash for concrete based upon foam index testing. The fly ash is mixed with an activator solution sufficient to initiate a geopolymerization reaction and for a geopolymerized fly ash. The geopolymerized fly ash is granulated. The geopolymerized fly ash is considered usable fly ash for concrete according to foam index testing. The geopolymerized fly ash may have a foam index less than 35% of the foam index of the untreated fly ash, and in some cases less than 10% of the foam index of the untreated fly ash. The activator solution may contain an alkali metal hydroxide, carbonate, silicate, aluminate, or mixtures thereof.

  6. Characterization and validation of an in silico toxicology model to predict the mutagenic potential of drug impurities*

    SciTech Connect (OSTI)

    Valerio, Luis G., E-mail: luis.valerio@fda.hhs.gov [Science and Research Staff, Office of Pharmaceutical Science, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993–0002 (United States); Cross, Kevin P. [Leadscope, Inc., 1393 Dublin Road, Columbus, OH, 43215–1084 (United States)] [Leadscope, Inc., 1393 Dublin Road, Columbus, OH, 43215–1084 (United States)

    2012-05-01T23:59:59.000Z

    Control and minimization of human exposure to potential genotoxic impurities found in drug substances and products is an important part of preclinical safety assessments of new drug products. The FDA's 2008 draft guidance on genotoxic and carcinogenic impurities in drug substances and products allows use of computational quantitative structure–activity relationships (QSAR) to identify structural alerts for known and expected impurities present at levels below qualified thresholds. This study provides the information necessary to establish the practical use of a new in silico toxicology model for predicting Salmonella t. mutagenicity (Ames assay outcome) of drug impurities and other chemicals. We describe the model's chemical content and toxicity fingerprint in terms of compound space, molecular and structural toxicophores, and have rigorously tested its predictive power using both cross-validation and external validation experiments, as well as case studies. Consistent with desired regulatory use, the model performs with high sensitivity (81%) and high negative predictivity (81%) based on external validation with 2368 compounds foreign to the model and having known mutagenicity. A database of drug impurities was created from proprietary FDA submissions and the public literature which found significant overlap between the structural features of drug impurities and training set chemicals in the QSAR model. Overall, the model's predictive performance was found to be acceptable for screening drug impurities for Salmonella mutagenicity. -- Highlights: ? We characterize a new in silico model to predict mutagenicity of drug impurities. ? The model predicts Salmonella mutagenicity and will be useful for safety assessment. ? We examine toxicity fingerprints and toxicophores of this Ames assay model. ? We compare these attributes to those found in drug impurities known to FDA/CDER. ? We validate the model and find it has a desired predictive performance.

  7. Study of recycling impurity retention in Alcator C-mod

    E-Print Network [OSTI]

    Chung, Taekyun

    2004-01-01T23:59:59.000Z

    This work was aimed at reproducing experimental results in impurity compression of Ar, as well as the screening of recycling and non-recycling impurities from reaching the core plasma. As part of the study the code was ...

  8. Simulation of iron impurity gettering in crystalline silicon solar cells

    E-Print Network [OSTI]

    Powell, Douglas M. (Douglas Michael)

    2012-01-01T23:59:59.000Z

    This work discusses the Impurity-to-Efficiency (12E) simulation tool and applet. The 12E simulator models the physics of iron impurity gettering in silicon solar cells during high temperature processing. The tool also ...

  9. Process and system for removing impurities from a gas

    DOE Patents [OSTI]

    Henningsen, Gunnar; Knowlton, Teddy Merrill; Findlay, John George; Schlather, Jerry Neal; Turk, Brian S

    2014-04-15T23:59:59.000Z

    A fluidized reactor system for removing impurities from a gas and an associated process are provided. The system includes a fluidized absorber for contacting a feed gas with a sorbent stream to reduce the impurity content of the feed gas; a fluidized solids regenerator for contacting an impurity loaded sorbent stream with a regeneration gas to reduce the impurity content of the sorbent stream; a first non-mechanical gas seal forming solids transfer device adapted to receive an impurity loaded sorbent stream from the absorber and transport the impurity loaded sorbent stream to the regenerator at a controllable flow rate in response to an aeration gas; and a second non-mechanical gas seal forming solids transfer device adapted to receive a sorbent stream of reduced impurity content from the regenerator and transfer the sorbent stream of reduced impurity content to the absorber without changing the flow rate of the sorbent stream.

  10. Anomalous temperature behavior of Sn impurities

    SciTech Connect (OSTI)

    Haskel, D.; Shechter, H. (Department of Physics, Technion, Haifa (Israel)); Stern, E.A.; Newville, M. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)); Yacoby, Y. (Racah Institute of Physics, Hebrew University, Jerusalem (Israel))

    1993-06-01T23:59:59.000Z

    Sn impurities in Pb and Ag hosts have been investigated by Moessbauer effect and in Pb by x-ray-absorption fine-structure (XAFS) studies. The Sn atoms are dissolved up to at least 2 at. % in Pb and up to at least 8 at. % in Ag for the temperature ranges investigated. The concentration limit for Sn-Sn interactions is 1 at. % for Pb and 2 at. % for Ag as determined experimentally by lowering the Sn concentration until no appreciable change occurs in the Moessbauer effect. XAFS measurements verify that the Sn impurities in Pb are dissolved and predominantly at substitutional sites. For both hosts the temperature dependence of the spectral intensities of isolated Sn impurities below a temperature [ital T][sub 0] is as expected for vibrating about a lattice site. Above [ital T][sub 0] the Moessbauer spectral intensity exhibits a greatly increased rate of drop-off with temperature without appreciable broadening. This drop-off is too steep to be explained by ordinary anharmonic effects and can be explained by a liquidlike rapid hopping of the Sn, localized about a lattice site. Higher-entropy-density regions of radii somewhat more than an atomic spacing surround such impurities, and can act as nucleation sites for three-dimensional melting.

  11. Study of Impurity-Helium Condensates Formed by Multishell Nanoclusters

    E-Print Network [OSTI]

    Mao, Shun

    2014-12-17T23:59:59.000Z

    Impurity-helium condensates (IHCs) are porous gel-like materials created by injecting a mixed beam of helium gas and an impurity gas into super fluid 4He. Van der Waals forces lead to the formation of clusters of impurities each surrounded by a thin...

  12. Impurity Doping Effect in High T c Superconductors

    E-Print Network [OSTI]

    Impurity Doping Effect in High T c Superconductors Yong­Jihn Kim and K. J. Chang Department observed that impurity doping and/or ion­beam­induced dam­ age in high T c superconductors cause a metal­ calization effect on superconductivity, we examine the variation of T c with increasing of impurity

  13. Silicon materials task of the low cost solar array project (Phase III). Effects of impurities and processing on silicon solar cells. Phase III summary and seventeenth quarterly report, Volume 2: analysis of impurity behavior

    SciTech Connect (OSTI)

    Hopkins, R.H.; Davis, J.R.; Rohatgi, A.; Campbell, R.B.; Blais, P.D.; Rai-Choudhury, P.; Stapleton, R.E.; Mollenkopf, H.C.; McCormick, J.R.

    1980-01-23T23:59:59.000Z

    The object of this phase of the program has been to investigate the effects of various processes, metal contaminants and contaminant-process interactions on the properties of silicon and on the performance of terrestrial silicon solar cells. The study encompassed topics including thermochemical (gettering) treatments, base doping concentration, base doping type (n vs. p), grain boundary-impurity interaction, non-uniformity of impurity distribution, long term effects of impurities, as well as synergic and complexing phenomena. The program approach consists in: (1) the growth of doubly and multiply-doped silicon single crystals containing a baseline boron or phosphorus dopant and specific impurities which produce deep levels in the forbidden band gap; (2) assessment of these crystals by chemical, microstructural, electrical and solar cell tests; (3) correlation of the impurity type and concentration with crystal quality and device performance; and (4) delineation of the role of impurities and processing on subsequent silicon solar cell performance. The overall results reported are based on the assessment of nearly 200 silicon ingots. (WHK)

  14. Fly ash enhanced metal removal process

    SciTech Connect (OSTI)

    Nonavinakere, S. [Plexus Scientific Corp., Annapolis, MD (United States); Reed, B.E. [West Virginia Univ., Morgantown, WV (United States). Dept. of Civil Engineering

    1995-12-31T23:59:59.000Z

    The primary objective of the study was to evaluate the effectiveness of fly ashes from local thermal power plants in the removal of cadmium, nickel, chromium, lead, and copper from aqueous waste streams. Physical and chemical characteristics of fly ashes were determined, batch isotherm studies were conducted. A practical application of using fly ash in treating spent electroless nickel (EN) plating baths by modified conventional precipitation or solid enhanced metal removal process (SEMR) was investigated. In addition to nickel the EN baths also contains completing agents such as ammonium citrate and succinic acid reducing agents such as phosphate and hypophosphite. SEMR experiments were conducted at different pHs, fly ash type and concentrations, and settling times.

  15. Environmental aspects of the Brandywine ash site

    SciTech Connect (OSTI)

    Simek, E.; Potera, G.; Schuller, R.; Herritt, M.; Wagner, R.

    1984-05-01T23:59:59.000Z

    The Brandywine ash site, located in Prince Georges County, Maryland, is owned and operated by the Potomac Electric Power Company (PEPCO). This site was designed specifically for the storage of the large quantities of coal ash produced at PEPCO's nearby Chalk Point Generating Station. Environmental Resources Management, Inc. (ERM), with assistance from the Maryland Department of Natural Resources, Tidewater Administration, conducted a study of this site for the Maryland Power Plant Siting Program (PPSP) to determine if ash constituents are adversely affecting the environment. Section 1 of this report is an introduction to coal ash and its physical/chemical characteristics. Section 2 describes the environment at the site and in adjacent areas. Within this setting, a description of the facility is presented as Section 3. Section 4 relies on the previous sections to point out any likely effects of the facility on the environment and to discount unlikely interactions. Key conclusions are presented in Section 5.

  16. INTOR impurity control and first wall system

    SciTech Connect (OSTI)

    Abdou, M.A.

    1983-04-01T23:59:59.000Z

    The highlights of the recent INTOR effort on examining the key issues of the impurity control/first wall system are summarized. The emphasis of the work was an integrated study of the edge-region physics, plasma-wall interaction, materials, engineering and magnetic considerations associated with the poloidal divertor and pump limiter. The development of limiter and divertor collector plate designs with an acceptable lifetime was a major part of the work.

  17. Stabilization/solidification of TSCA incinerator ash

    SciTech Connect (OSTI)

    Spence, R.D.; Trotter, D.R.; Francis, C.L.; Morgan, I.L.

    1994-06-01T23:59:59.000Z

    Stabilization/solidification is a well-known waste treatment technique that utilizes different additives and processes. The Phoenix Ash Technology of the Technical Innovation Development Engineering Company is such a technique that uses Cass C fly ash and mechanical pressure to make brick waste forms out of solid wastes, such as the bottom ash from the Toxic Substances Control Act incinerator at the Oak Ridge K-25 Site. One advantage of this technique is that no volume increase over the bulk volume of the bottom ash occurs. This technique should have the same high pH stabilization for Resource Conservation and Recovery Act metals as similar techniques. Also, consolidation of the bottom ash minimizes the potential problems of material dispersion and container corrosion. The bottom ash was spiked with {sup 99}{Tc} to test the effectiveness of the bricks as a physical barrier. The {sup 99}{Tc} leachability index measured for these bricks was 6.8, typical for the pertechnetate anion in cementitious waste forms, indicating that these bricks have accessible porosity as high as that of other cementitious waste forms, despite the mechanical compression, higher waste form density, and water resistant polymer coating.

  18. Utilization of pulverized fuel ash in Malta

    SciTech Connect (OSTI)

    Camilleri, Josette [Department of Building and Civil Engineering, Faculty of Architecture and Civil Engineering, University of Malta, Msida (Malta); Sammut, Michael [Department of Pathology, St. Luke's Hospital, G'Mangia (Malta); Montesin, Franco E. [Department of Building and Civil Engineering, Faculty of Architecture and Civil Engineering, University of Malta, Msida (Malta)]. E-mail: franco.montesin@um.edu.mt

    2006-07-01T23:59:59.000Z

    In Malta all of the waste produced is mixed and deposited at various sites around the island. None of these sites were purpose built, and all of the waste is above groundwater level. The landfills are not engineered and do not contain any measures to collect leachate and gases emanating from the disposal sites. Another waste, which is disposed of in landfills, is pulverized fuel ash (PFA), which is a by-product of coal combustion by the power station. This has been disposed of in landfill, because its use has been precluded due to the radioactivity of the ashes. The aim of this study was to analyze the chemical composition of the pulverized fuel ash and to attempt to utilize it as a cement replacement in normal concrete mixes in the construction industry. The levels of radiation emitted from the ashes were measured by gamma spectrometry. The results of this study revealed that although at early ages cement replacement by PFA resulted in a reduction in compressive strength (P = 0), when compared to the reference concrete at later ages the strengths measured on concrete cores were comparable to the reference concrete (P > 0.05). The utilization of PFA up to 20% cement replacement in concrete did not raise the radioactivity of the concrete. In conclusion, utilization of PFA in the construction industry would be a better way of disposing of the ashes rather than controlling the leachate and any radioactivity emitted by the landfilled ashes.

  19. Assessment of Embrittlement of VHTR Structural Alloys in Impure Helium Environments

    SciTech Connect (OSTI)

    Crone, Wendy; Cao, Guoping; Sridhara, Kumar

    2013-05-31T23:59:59.000Z

    The helium coolant in high-temperature reactors inevitably contains low levels of impurities during steady-state operation, primarily consisting of small amounts of H{sub 2}, H{sub 2}O, CH{sub 4}, CO, CO{sub 2}, and N{sub 2} from a variety of sources in the reactor circuit. These impurities are problematic because they can cause significant long-term corrosion in the structural alloys used in the heat exchangers at elevated temperatures. Currently, the primary candidate materials for intermediate heat exchangers are Alloy 617, Haynes 230, Alloy 800H, and Hastelloy X. This project will evaluate the role of impurities in helium coolant on the stress-assisted grain boundary oxidation and creep crack growth in candidate alloys at elevated temperatures. The project team will: • Evaluate stress-assisted grain boundary oxidation and creep crack initiation and crack growth in the temperature range of 500-850°C in a prototypical helium environment. • Evaluate the effects of oxygen partial pressure on stress-assisted grain boundary oxidation and creep crack growth in impure helium at 500°C, 700°C, and 850°C respectively. • Characterize the microstructure of candidate alloys after long-term exposure to an impure helium environment in order to understand the correlation between stress-assisted grain boundary oxidation, creep crack growth, material composition, and impurities in the helium coolant. • Evaluate grain boundary engineering as a method to mitigate stress-assisted grain boundary oxidation and creep crack growth of candidate alloys in impure helium. The maximum primary helium coolant temperature in the high-temperature reactor is expected to be 850-1,000°C.Corrosion may involve oxidation, carburization, or decarburization mechanisms depending on the temperature, oxygen partial pressure, carbon activity, and alloy composition. These corrosion reactions can substantially affect long-term mechanical properties such as crack- growth rate and fracture toughness, creep rupture, and fatigue. Although there are some studies on the effects of impurities in helium coolant on creep rupture and fatigue strength, very little is known about their effects on creep crack initiation and crack growth rate at elevated temperatures.

  20. Scale-Up and Demonstration of Fly Ash Ozonation Technology

    SciTech Connect (OSTI)

    Rui Afonso; R. Hurt; I. Kulaots

    2006-03-01T23:59:59.000Z

    The disposal of fly ash from the combustion of coal has become increasingly important. When the fly ash does not meet the required specification for the product or market intended, it is necessary to beneficiate it to achieve the desired quality. This project, conducted at PPL's Montour SES, is the first near full-scale ({approx}10 ton/day), demonstration of ash ozonation technology. Bituminous and sub bituminous ashes, including two ash samples that contained activated carbon, were treated during the project. Results from the tests were very promising. The ashes were successfully treated with ozone, yielding concrete-suitable ash quality. Preliminary process cost estimates indicate that capital and operating costs to treat unburned carbon are competitive with other commercial ash beneficiation technologies at a fraction of the cost of lost sales and/or ash disposal costs. This is the final technical report under DOE Cooperative Agreement No.: DE-FC26-03NT41730.

  1. Petrography and chemistry of high-carbon fly ash from the Shawnee Power Station, Kentucky

    SciTech Connect (OSTI)

    Hower, J.C.; Thomas, G.A.; Robertson, J.D.; Wong, A.S. [Univ. of Kentucky, Lexington, KY (United States); Clifford, D.S.; Eady, J.D. [Tennessee Valley Authority, Chattanooga, TN (United States)

    1996-01-01T23:59:59.000Z

    The Shawnee power station in western Kentucky consists of ten 150-MW units, eight of which burn low-sulfur (< 1 wt %) eastern Kentucky and central West Virginia coal. The other units burn medium- and high-sulfur (> 1 wt %) coal in an atmospheric fluidized-bed combustion unit and in a research unit. The eight low-sulfur coal units were sampled in a 1992 survey of Kentucky utilities. Little between-unit variation is seen in the ash-basis major oxide and minor element chemistry. The carbon content of the fly ashes varies from 5 to 25 wt %. Similarly, the isotropic and anisotropic coke in the fly ash varies from 6% to 42% (volume basis). Much of the anisotropic coke is a thin-walled macroporous variety, but there is a portion that is a thick-walled variety similar to a petroleum coke.

  2. Petrography and chemistry of fly ash from the Shawnee Power Station, Kentucky

    SciTech Connect (OSTI)

    Hower, J.C.; Thomas, G.A.; Wild, G.D. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Clifford, D.S.; Eady, J.D. [Tennessee Valley Authority, Chattanooga, TN (United States)

    1994-12-31T23:59:59.000Z

    The Shawnee Power Station in western Kentucky consists of ten 150 MW units, eight of which burn low-sulfur eastern Kentucky and central West Virginia coal. The other units bum medium and high-sulfur coal in an AFBC unit and in a research unit. The eight low-sulfur coal units were sampled in a 1992 survey of Kentucky utilities. Little between-unit variation is seen in the ash-basis major oxide and minor element chemistry. The carbon content of the fly ashes varies from 5 to 25%. Similarly, the isotropic and anisotropic coke in the fly ash varies from 6 to 42% (volume basis). Much of the anisotropic coke is a thin-walled macroporous variety but there is a portion which is a thick-walled variety similar to a petroleum coke.

  3. Four-year prospective study of the respiratory effects of volcanic ash from Mt. St. Helens

    SciTech Connect (OSTI)

    Buist, A.S.; Vollmer, W.M.; Johnson, L.R.; Bernstein, R.S.; McCamant, L.E.

    1986-04-01T23:59:59.000Z

    This report describes the 4-yr follow-up of 712 loggers exposed over an extended period to varying levels of fresh volcanic ash from the 1980 eruptions of Mt. St. Helens. Concerns related to the irritant effect the ash might have on the airways and also to its fibrogenic potential if exposures were intense and continued over many years. Our subjects were divided into 3 groups: high, low, and no exposure. Baseline testing was begun in June 1980, 1 month after the major eruption, and follow-up testing continued on an annual basis through 1984; 88% of the loggers have been tested at least 3 times. Analysis of lung function data showed that a significant, exposure-related decline in FEV1 occurred during the first year after the eruption. The decline was short-lived, however, and by 1984 the differences between exposure groups were no longer significant. Self-reported symptoms of cough, phlegm, and wheeze showed a similar pattern. No ash-related changes were seen in chest roentgenograms taken in 1980 and in 1984. Our findings are consistent with the hypothesis that the inhaled ash caused mucus hypersecretion and/or airway inflammation that reversed when the exposure levels decreased. The ash levels to which the loggers were exposed were low compared with permissible occupational levels for nuisance dusts, but generally higher than the total suspended particulate levels permissible in ambient air.

  4. Z-Stable ASH Algebras

    E-Print Network [OSTI]

    2008-05-01T23:59:59.000Z

    of nuclear C*-algebras for which the Elliott conjecture has been confirmed so far consist ... of evidence linking Z to Elliott's program to classify separable, nuclear.

  5. Bioaccumulation Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010

    SciTech Connect (OSTI)

    Adams, Marshall [ORNL; Brandt, Craig C [ORNL; Fortner, Allison M [ORNL

    2012-05-01T23:59:59.000Z

    In December 2008, an ash dike at the Tennessee Valley Authority (TVA) Kingston Fossil Plant ruptured, releasing over one billion gallons of coal fly ash into the Emory and Clinch Rivers. Coal fly ash may contain several contaminants of concern, but of these selenium (Se) and arsenic (As) have been highlighted because of their toxicity and tendency to bioaccumulate in aquatic food chains. To assess the potential impact of the spilled fly ash on humans and the environment, a comprehensive biological and environmental monitoring program was established, for which resident aquatic organisms (among other sample media) are collected to determine contaminant exposure and evaluate the risk to humans and wildlife. Studies on bioaccumulation and fish health are major components of the TVA Biological Monitoring Program for the Kingston fly ash project. These studies were initiated in early Spring 2009 for the purposes of: (1) documenting the levels of fly ash-associated metals in various tissues of representative sentinel fish species in the area of the fly ash spill, (2) determining if exposure to fly ash-associated metals causes short, intermediate, or long-term health effects on these sentinel fish species, (3) assessing if there are causal relationships between exposure (to metals) and effects on fish, (4) evaluating, along with information regarding other ecological and physicochemical studies, the nature and route of contaminant transfer though food chains into higher level consumers, (5) providing important information for the Ecological Risk Assessment (ERA) for the Kingston fly ash project, and (6) serving as an important technology transfer or model study focused on how to best evaluate the environmental effects of fly ash, not only at the Kingston site, but also at sites on other aquatic systems where coal-fired generating stations are located. This report summarizes the bioaccumulation results from the first two years of study after the fly ash spill, including four seasonal collections: Spring 2009, Fall 2009, Spring 2010, and Fall 2010. Both the Spring and Fall studies have focused on 3-4 sentinel fish species that represent different feeding habits, behaviors, and home ranges. In addition to bioaccumulation studies, the Spring investigations also included evaluation of fish health and reproductive integrity on the same fish used for bioaccumulation. Two associated reports present the fish health (Adams et al 2012) and reproductive studies (Greeley et al 2012) conducted in 2009 and 2010. The fish health study conducted in conjunction with the bioaccumulation and reproductive study is critical for assessing and evaluating possible causal relationships between contaminant exposure (bioaccumulation) and the response of fish to exposure as reflected by the various measurements of fish health. This report emphasizes evaluation of arsenic and selenium bioaccumulation in fish and consists of four related studies (Sections 2-5) including, (1) bioaccumulation in liver and ovaries, (2) bioaccumulation in whole body gizzard shad (Dorosoma cepedianum), (3) bioaccumulation in muscle tissue or fillets, and (4) a reconstruction analysis which establishes the relationship between selenium in muscle tissue and that of the whole body of bluegill (Lepomis machrochirus). Metals other than arsenic and selenium are evaluated separately in Section 6. This report focuses on selenium and arsenic for the following reasons: (1) based on baseline studies conducted in early 2009 in the Emory and Clinch River, only two potentially fly-ash related metals, selenium and arsenic, appeared to be elevated above background or reference levels, (2) selenium and arsenic are two of the metals in coal ash that are known to bioaccumulate and cause toxicity in wildlife, and (3) based on bioaccumulation studies of bluegill and carp (Cyprinus carpio) in the Stilling Pond during Spring 2009, which would represent a worst case situation for metal bioaccumulation, selenium and arsenic were the only two metals consistently elevated above background levels in fish. E

  6. Hydrothermal reaction of fly ash. Final report

    SciTech Connect (OSTI)

    Brown, P.W.

    1994-12-31T23:59:59.000Z

    The reactions which occur when fly ash is treated under hydrothermal conditions were investigated. This was done for the following primary reasons. The first of these is to determine the nature of the phases that form to assess the stabilities of these phases in the ambient environment and, finally, to assess whether these phases are capable of sequestering hazardous species. The second reason for undertaking this study was whether, depending on the composition of the ash and the presence of selected additives, it would be possible under hydrothermal conditions to form compounds which have cementitious properties. Formation of four classes of compounds, which bracket likely fly ash compositional ranges, were selected for study. The classes are calcium silicate hydrates, calcium selenates, and calcium aluminosulfates, and silicate-based glasses. Specific compounds synthesized were determined and their stability regions assessed. As part of stability assessment, the extent to which selected hazardous species are sequestered was determined. Finally, the cementing properties of these compounds were established. The results obtained in this program have demonstrated that mild hydrothermal conditions can be employed to improve the reactivity of fly ash. Such improvements in reactivity can result in the formation of monolithic forms which may exhibit suitable mechanical properties for selected applications as building materials. If the ashes involved are considered hazardous, the mechanical properties exhibited indicated the forms could be handled in a manner which facilitates their disposal.

  7. Approaches to the petrographic characterization of fly ash

    SciTech Connect (OSTI)

    Hower, J.C.; Rathbone, R.F.; Graham, U.M. [Univ. of Kentucky, Lexington, KY (United States)] [and others

    1995-08-01T23:59:59.000Z

    The enhanced understanding of fly ash properties provided by petrographic analysis, a level of detail chemical analysis cannot provide, will be essential in the upgrading and utilization of fly ash produced in boilers retrofitted to meet clean air standards. Howe et al estimated that over 25% of the fly ash produced in Kentucky in 1992 would not have met the Kentucky Department of Transportation limit of 3% loss-on-ignition (LOI) for class F fly ash used as a Portland cement admixture. The conversion of boilers to low-NO{sub x} emission units increases fly ash carbon, hence LOI, by 150-200% rendering the fly ash unsuitable for highway construction use in concrete. The preservation of fly ash`s market share will require increased attention to the removal of excess carbon from the fly ash. In this paper, we will discuss the basic components of fly ash. An example of the petrographic analysis of fly ash from a Kentucky power plant will be used to illustrate the partitioning of fly ash components by size, as well as within the fly ash collection system.

  8. Putting the Spin on Graphite: Observing the Spins of Impurity...

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

    the Spins of Impurity Atoms Align Friday, February 28, 2014 The existence of magnetism in graphite is a very intriguing subject. The possibility to exploit the magnetic...

  9. Extraction of trace metals from fly ash

    DOE Patents [OSTI]

    Blander, Milton (Palos Park, IL); Wai, Chien M. (Moscow, ID); Nagy, Zoltan (Woodridge, IL)

    1984-01-01T23:59:59.000Z

    A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous, the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like, with the process being carried out by contacting the fly ash with AlCl.sub.3 in an alkali halide melt to react the trace metals with the AlCl.sub.3 to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  10. Extraction of trace metals from fly ash

    DOE Patents [OSTI]

    Blander, M.; Wai, C.M.; Nagy, Z.

    1983-08-15T23:59:59.000Z

    A process is described for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous. The fly ash has a silicate base and contains surface deposits of the trace metals as oxides, chlorides or the like. The process is carried out by contacting the fly ash with AlCl/sub 3/ in an alkali halide melt to react the trace metals with the AlCl/sub 3/ to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

  11. ash utilization symposium: Topics by E-print Network

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

    Websites Summary: Center for By-Products Utilization USE OF CLASS F FLY ASH AND CLEAN-COAL ASH BLENDS FOR CAST Report No.CBU-1996-07 July 1996 Presented and Published at the...

  12. Eco-friendly fly ash utilization: potential for land application

    SciTech Connect (OSTI)

    Malik, A.; Thapliyal, A. [Indian Institute of Technology Delhi, New Delhi (India)

    2009-07-01T23:59:59.000Z

    The increase in demand for power in domestic, agricultural, and industrial sectors has increased the pressure on coal combustion and aggravated the problem of fly ash generation/disposal. Consequently the research targeting effective utilization of fly ash has also gained momentum. Fly ash has proved to be an economical substitute for expensive adsorbents as well as a suitable raw material for brick manufacturing, zeolite synthesis, etc. Fly ash is a reservoir of essential minerals but is deficient in nitrogen and phosphorus. By amending fly ash with soil and/or various organic materials (sewage sludge, bioprocess materials) as well as microbial inoculants like mycorrhizae, enhanced plant growth can be realized. Based on the sound results of large scale studies, fly ash utilization has grown into prominent discipline supported by various internationally renowned organizations. This paper reviews attempts directed toward various utilization of fly ash, with an emphasis on land application of organic/microbial inoculants amended fly ash.

  13. ash solvent extraction: Topics by E-print Network

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

    Alessandro 2013-01-01 27 ASH PNEUMATIC TRANSPORT UNDER ELECTROFILTERS OF UNIT 5 THERMAL POWER PLANT TUZLA CiteSeer Summary: Ash pneumatic transport is basic on fact that at...

  14. TREATMENT OF CYANIDE SOLUTIONS AND SLURRIES USING AIR-SPARGED HYDROCYCLONE (ASH) TECHNOLOGY

    SciTech Connect (OSTI)

    Jan D. Miller; Terrence Chatwin; Jan Hupka; Doug Halbe; Tao Jiang; Bartosz Dabrowski; Lukasz Hupka

    2003-03-31T23:59:59.000Z

    The two-year Department of Energy (DOE) project ''Treatment of Cyanide Solutions and Slurries Using Air-Sparged Hydrocyclone (ASH) Technology'' (ASH/CN) has been completed. This project was also sponsored by industrial partners, ZPM Inc., Elbow Creek Engineering, Solvay Minerals, EIMCO-Baker Process, Newmont Mining Corporation, Cherokee Chemical Co., Placer Dome Inc., Earthworks Technology, Dawson Laboratories and Kennecott Minerals. Development of a new technology using the air-sparged hydrocyclone (ASH) as a reactor for either cyanide recovery or destruction was the research objective. It was expected that the ASH could potentially replace the conventional stripping tower presently used for HCN stripping and absorption with reduced power costs. The project was carried out in two phases. The first phase included calculation of basic processing parameters for ASH technology, development of the flowsheet, and design/adaptation of the ASH mobile system for hydrogen cyanide (HCN) recovery from cyanide solutions. This was necessary because the ASH was previously used for volatile organics removal from contaminated water. The design and modification of the ASH were performed with the help from ZPM Inc. personnel. Among the modifications, the system was adapted for operation under negative pressure to assure safe operating conditions. The research staff was trained in the safe use of cyanide and in hazardous material regulations. Cyanide chemistry was reviewed resulting in identification of proper chemical dosages for cyanide destruction, after completion of each pilot plant run. The second phase of the research consisted of three field tests that were performed at the Newmont Mining Corporation gold cyanidation plant near Midas, Nevada. The first field test was run between July 26 and August 2, 2002, and the objective was to demonstrate continuous operation of the modified ASH mobile system. ASH units were applied for both stripping and absorption, to recover cyanide, using the acidification-volatilization-reabsorption chemistry. Plant barren cyanide solution was used during the field tests. The original ASH system used for the field tests had been designed and fabricated by ZPM Inc. to remove volatile organic compounds from ground water. The system, even with a number of modifications, could not operate at optimum conditions for cyanide recovery. Reactors and pumps installed in the mobile system only allowed for the treatment of clear solutions, not slurries. Also the original mobile system was limited with respect to Q, the relative air flow rate, and the extent of recovery in a single stage. Due to the lack of automatic controls, the system required constant supervision of the University of Utah (U/U) team. In spite of these difficulties, application of the ASH mobile system was particularly attractive due to compactness of the apparatus and less than 1 second residence time of the aqueous phase in the cyclones. The performance of the ASH system was evaluated by comparison with theoretical predictions.

  15. Impurity pellet injection experiments at TFTR

    SciTech Connect (OSTI)

    Marmar, E.S.

    1992-01-01T23:59:59.000Z

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection ( lithiumization'). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li[sup +] line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li[sup +] emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from [approximately]0.3 to [approximately]7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  16. 488-D Ash Basin Vegetative Cover Treatibility Study

    SciTech Connect (OSTI)

    Barton, Christopher; Marx, Don; Blake, John; Adriano, Domy; Koo, Bon-Jun; Czapka, Stephen

    2003-01-01T23:59:59.000Z

    The 488-D Ash Basin is an unlined containment basin that received ash and coal reject material from the operation of a powerhouse at the USDOE's Savannah River Site, SC. They pyretic nature of the coal rejects has resulted in the formation of acidic drainage (AD), which has contributed to groundwater deterioration and threatens biota in down gradient wetlands. Establishment of a vegetative cover was examined as a remedial alternative for reducing AD generation within this system by enhanced utilization of rainwater and subsequent non-point source water pollution control. The low nutrient content, high acidity, and high salinity of the basin material, however, was deleterious to plant survivability. As such, studies to identify suitable plant species and potential adaptations, and pretreatment techniques in the form of amendments, tilling, and/or chemical stabilization were needed. A randomized block design consisting of three subsurface treatments (blocks) and five duplicated surface amendments (treatments) was developed. One hundred inoculated pine trees were planted on each plot. Herbaceous species were also planted on half of the plots in duplicated 1-m2 beds. After two growing seasons, deep ripping, subsurface amendments and surface covers were shown to be essential for the successful establishment of vegetation on the basin. This is the final report of the study.

  17. Long range forces between atomic impurities in liquid helium

    E-Print Network [OSTI]

    Long range forces between atomic impurities in liquid helium J. Dupont-Roc Laboratoire Kastler in a polarizable medium. We show that atomic impurities in liquid helium may indeed realize repulsive forces embedded in liquid helium, super uid or not. Solid helium have also been used. Successful theoretical

  18. Single atom impurity in a single molecular transistor

    SciTech Connect (OSTI)

    Ray, S. J., E-mail: ray.sjr@gmail.com [Institute of Materials Science, Technical University of Darmstadt, Alarich-Weiss Str. 2, 64287 Darmstadt (Germany)

    2014-10-21T23:59:59.000Z

    The influence of an impurity atom on the electrostatic behaviour of a Single Molecular Transistor was investigated through Ab-initio calculations in a double-gated geometry. The charge stability diagram carries unique signature of the position of the impurity atom in such devices which together with the charging energy of the molecule could be utilised as an electronic fingerprint for the detection of such impurity states in a nano-electronic device. The two gated geometry allows additional control over the electrostatics as can be seen from the total energy surfaces (for a specific charge state), which is sensitive to the positions of the impurity. These devices which are operational at room temperature can provide significant advantages over the conventional silicon based single dopant devices functional at low temperature. The present approach could be a very powerful tool for the detection and control of individual impurity atoms in a single molecular device and for applications in future molecular electronics.

  19. 2007 world of coal ash conference proceedings

    SciTech Connect (OSTI)

    NONE

    2007-07-01T23:59:59.000Z

    The theme of the conference was science, applications and sustainability. Papers are presented under the following topics: aggregates/geotechnology; agriculture; ash facility; management; CCT products; cement and concrete; chemistry and mineralogy; emerging technology; environmental; LOI/beneficiation/handling; mercury; mining and regulations and standards. The poster papers are included as well.

  20. Theory of Deep Impurity Levels in Cucl

    E-Print Network [OSTI]

    REN, SY; Allen, Roland E.; DOW, JD; LEFKOWITZ, I.

    1982-01-01T23:59:59.000Z

    ? T,(d) Cu site SbBi Poli B Te Si As Ge Al Alt Ga r P ,'.:SnIn Hg0 N Se. ' PbTXZnCF . I C C1S? I I!1 Egop 3- Tp Cg si OJ LIJ I i II i I O OTENTIAL (eV)IMPUR ITY PO for theetric (d??-1 ee ' ??-1'k ) defect levels t e do o od F Cu... with Eqs. (3.2) and (3.3). We imposed the following re- 1205 1982 The American Physical Society 1206 REN, ALLEN, DOW, AND LEFKOWITZ TABLE I. Parameters of the tight-binding model in eV. With these parameters the charges on the Cu and Cl ions are...

  1. Extended recursion in operator space (EROS), a new impurity solver for the single impurity Anderson model

    SciTech Connect (OSTI)

    Albers, Robert C [Los Alamos National Laboratory; Julien, Jean P [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    We have developed a new efficient and accurate impurity solver for the single impurity Anderson model (SIAM), which is based on a non-perturbative recursion technique in a space of operators and involves expanding the self-energy as a continued fraction. The method has no special occupation number or temperature restrictions; the only approximation is the number of levels of the continued fraction retained in the expansion. We also show how this approach can be used as a new approach to Dynamical Mean Field Theory (DMTF) and illustrate this with the Hubbard model. The three lowest orders of recursion give the Hartree-Fock, Hubbard I, and Hubbard III approximations. A higher level of recursion is able to reproduce the expected 3-peak structure in the spectral function and Fermi liquid behavior.

  2. Properties of concrete containing wood/coal fly ash mixtures

    SciTech Connect (OSTI)

    Boylan, D.M.; Larrimore, C.L.; Fouad, F.

    1999-07-01T23:59:59.000Z

    Utilities are increasingly interested in co-firing wood with coal in existing pulverized coal units. The co-firing technology is a means of developing a relatively low-cost renewable energy resource, as well as of supporting customers and community by making energy with biomass that might otherwise have been land-filled. However, recent changes in the ASTM C618 standard for fly ash as cement replacement restrict the definition of fly ash that includes non-coal sources. As a result, wood co-firing could affect the market for the fly ash, reducing ash sales revenue, increasing ash disposal costs, and overall substantially increasing the cost of the co-firing technology. In order to address concerns about the effect of wood ash/coal ash mixtures on concrete properties, a study was conducted by University of Alabama at Birmingham, Southern Company, EPRI, and the State of Alabama. This study compared the effects on properties of concrete made with fly ash from coal and made with fly ash from co-firing up to 30% wood with coal. Fly ashes from three plants were used, with two of the ashes from actual co-firing experience and the third an artificial blend of wood and coal ash. Concrete test cylinders were made of several cement/fly ash mixes, and enough were made to allow testing periodically over a one year time period. Test measurements included workability, setting time, air content, compressive and flexural strength, rapid chloride permeability and freeze thaw. It was concluded on the basis of these tests that the wood ash content had no detrimental effect on the plastic and hardened properties of the concrete.

  3. Extraction process for removing metallic impurities from alkalide metals

    DOE Patents [OSTI]

    Royer, Lamar T. (Knoxville, TN)

    1988-01-01T23:59:59.000Z

    A development is described for removing metallic impurities from alkali metals by employing an extraction process wherein the metallic impurities are extracted from a molten alkali metal into molten lithium metal due to the immiscibility of the alkali metals in lithium and the miscibility of the metallic contaminants or impurities in the lithium. The purified alkali metal may be readily separated from the contaminant-containing lithium metal by simple decanting due to the differences in densities and melting temperatures of the alkali metals as compared to lithium.

  4. The impact of impurities on long-term PEMFC performance

    SciTech Connect (OSTI)

    Garzon, Fernando H [Los Alamos National Laboratory; Lopes, Thiago [Los Alamos National Laboratory; Rockward, Tommy [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Sansinena, Jose - Maria [Los Alamos National Laboratory; Kienitz, Brian [LLNL

    2009-06-23T23:59:59.000Z

    Electrochemical experimentation and modeling indicates that impurities degrade fuel cell performance by a variety of mechanisms. Electrokinetics may be inhibited by catalytic site poisoning from sulfur compounds and CO and by decreased local proton activity and mobility caused by the presence of foreign salt cations or ammonia. Cation impurity profiles vary with current density, valence and may change local conductivity and water concentrations in the ionomer. Nitrogen oxides and ammonia species may be electrochemically active under fuel cell operating conditions. The primary impurity removal mechanisms are electrooxidation and water fluxes through the fuel cell.

  5. Alternating current response of carbon nanotubes with randomly distributed impurities

    SciTech Connect (OSTI)

    Hirai, Daisuke; Watanabe, Satoshi [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Yamamoto, Takahiro [Department of Electrical Engineering and Department of Liberal Arts (Physics), Tokyo University of Science, 6-3-1 Niijuku, Katsushika, Tokyo 125-8585 (Japan)

    2014-10-27T23:59:59.000Z

    The increasing need for nanodevices has necessitated a better understanding of the electronic transport behavior of nanomaterials. We therefore theoretically examine the AC transport properties of metallic carbon nanotubes with randomly distributed impurities. We find that the long-range impurity scattering increases the emittance, but does not affect the DC conductance. The estimated dwell time of electrons increases with the potential amplitudes. That is, multiple scattering by the impurities increases the kinetic inductance in proportion to the dwell time, which eventually increases the emittance. We believe that our findings can contribute significantly to nanodevice development.

  6. Water quality investigation of Kingston Fossil Plant dry ash stacking

    SciTech Connect (OSTI)

    Bohac, C.E.

    1990-04-01T23:59:59.000Z

    Changing to a dry ash disposal systems at Kingston Fossil Plant (KFP) raises several water quality issues. The first is that removing the fly ash from the ash pond could alter the characteristics of the ash pond discharge to the river. The second concerns proper disposal of the runoff and possibly leachate from the dry ash stack. The third is that dry ash stacking might change the potential for groundwater contamination at the KFP. This report addresses each of these issues. The effects on the ash pond and its discharge are described first. The report is intended to provide reference material to TVA staff in preparation of environmental review documents for new ash disposal areas at Kingston. Although the investigation was directed toward analysis of dry stacking, considerations for other disposal options are also discussed. This report was reviewed in draft form under the title Assessment of Kingston Fossil Plant Dry Ash Stacking on the Ash Pond and Groundwater Quality.'' 11 refs., 3 figs., 18 tabs.

  7. Manufacture of ceramic tiles from fly ash

    DOE Patents [OSTI]

    Hnat, James G. (Collegeville, PA); Mathur, Akshay (Tampa, FL); Simpson, James C. (Perkiomenville, PA)

    1999-01-01T23:59:59.000Z

    The present invention relates to a process for forming glass-ceramic tiles. Fly ash containing organic material, metal contaminants, and glass forming materials is oxidized under conditions effective to combust the organic material and partially oxidize the metallic contaminants and the glass forming materials. The oxidized glass forming materials are vitrified to form a glass melt. This glass melt is then formed into tiles containing metallic contaminants.

  8. Manufacture of ceramic tiles from fly ash

    DOE Patents [OSTI]

    Hnat, J.G.; Mathur, A.; Simpson, J.C.

    1999-08-10T23:59:59.000Z

    The present invention relates to a process for forming glass-ceramic tiles. Fly ash containing organic material, metal contaminants, and glass forming materials is oxidized under conditions effective to combust the organic material and partially oxidize the metallic contaminants and the glass forming materials. The oxidized glass forming materials are vitrified to form a glass melt. This glass melt is then formed into tiles containing metallic contaminants. 6 figs.

  9. Market assessment of PFBC ash use

    SciTech Connect (OSTI)

    Bland, A. E.; Brown, T. H., Western Research Institute

    1998-01-01T23:59:59.000Z

    Pressurized fluidized bed combustion (PFBC) of coal is undergoing demonstration in the United States, as well as throughout the world. American Electric Power`s (AEP`s) bubbling PFBC 70 MWe Tidd demonstration program in Ohio and pilot-scale development at Foster Wheeler Energia Oy 10 MWth circulating PFBC at Karhula, Finland, have demonstrated the advantages of PFBC technology. Further technology development in the US is planned with the deployment of the technology at the MacIntosh Clean Coal project in Lakeland, Florida. Development of uses for solid wastes from PFBC coal-fired power systems is being actively pursued as part of the demonstration of PFBC technologies. Ashes collected from Foster Wheeler Energia Oy pilot circulating PFBC tests in Karhula, Finland, operating on (1) low sulfur subbituminous and (2) high sulfur bituminous coal; and ash from the AEP`s high-sulfur bituminous coal-fired bubbling PFBC in Brilliant, Ohio, were evaluated in laboratory and pilot-scale ash use testing at Western Research Institute (WRI).

  10. Coal ash by-product reutilization

    SciTech Connect (OSTI)

    Muncy, J. [Potomac Electric Power Co., Washington, DC (United States); Miller, B. [DYNA Corp., Upper Marlboro, MD (United States)

    1997-09-01T23:59:59.000Z

    Potomac Electric Power Company (PEPCO) has as part of its vision and value statement that, ``We are responsible stewards of environmental and corporate resources.`` With this moral imperative in mind, a project team was charged with initiating the Coal Pile Liner Project--installing a membrane liner under the existing coal storage pile at the Morgantown Generating Station. The existing coal yard facilities were constructed prior to the current environmental regulations, and it became necessary to upgrade the storage facilities to be environmentally friendly. The project team had two objectives in this project: (1) prevent coal pile leachate from entering the groundwater system; (2) test the viability of using coal ash by-products as an aggregate substitute for concrete applications. Both objectives were met, and two additional benefits were achieved as well: (1) the use of coal ash by-products as a coal liner produced significant cost savings to the project directly; (2) the use of coal ash by-products reduced plant operation and maintenance expenses.

  11. Muon spin depolarization in nonmagnetic metals doped with paramagnetic impurities

    SciTech Connect (OSTI)

    Heffner, R.H.

    1980-01-01T23:59:59.000Z

    The diffusion of muons and their magnetic interactions are treated by describing the physics to be learned from experiments which measure muon depolarization in metallic hosts doped with dilute concentrations of magnetic impurities. (GHT)

  12. Removal of impurities from dry scrubbed fluoride enriched alumina

    SciTech Connect (OSTI)

    Schuh, L. [ABB Corporate Research Center, Heidelberg (Germany); Wedde, G. [ABB Environmental, Oslo (Norway)

    1996-10-01T23:59:59.000Z

    The pot-gas from an aluminum electrolytic cell is cleaned by a dry scrubbing process using fresh alumina as a scrubbing agent. This alumina is enriched with fluorides and trace impurities in a closed loop system with the pots. The only significant removal of the impurities is due to metal tapping. An improved technique has been developed that is more effective than earlier stripper systems. The impurity-rich fine fraction (< 10 {micro}m) of the enriched alumina is partly attached to the coarser alumina. That attachment has to be broken. Selective impact milling under special moderate conditions and air classifying have shown to be a cost effective process for the removal of impurities. For iron (Fe) and phosphorus (P) about 30--70% can be removed by the separation of 0.5--1% of the alumina. Full scale tests have successfully confirmed these results.

  13. Impurity behavior during sawtooth activity in tokamak plasmas

    SciTech Connect (OSTI)

    Nicolas, T.; Garbet, X.; Sabot, R. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France)] [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Lütjens, H.; Luciani, J.-F. [Centre de Physique Théorique, Ecole Polytechnique, CNRS, F-91128 Palaiseau Cedex (France)] [Centre de Physique Théorique, Ecole Polytechnique, CNRS, F-91128 Palaiseau Cedex (France)

    2014-01-15T23:59:59.000Z

    The transport of impurities by a sawtooth crash is simulated with the XTOR-2F code. Impurities are modeled as passive scalars, evolving in the compressible MHD flow inferred from the main MHD plasma. For a peaked impurity density profile, the non-linear kink flow of the sawtooth crash redistributes the profile efficiently and most of the particles in the peak inside the q?=?1 surface are expelled. For an initially hollow impurity density profile, the crash leads to a significant penetration up to the magnetic axis. The results are compared with Kadomtsev's model. Despite essentially different mechanisms, the evolution of the particle content inside the q?=?1 surface for Kadomtsev's model and for the non-linear case are virtually identical for the peaked profile, while the model slightly overestimates penetration for the hollow case.

  14. Modelling of impurity balance for an aluminum smelter

    SciTech Connect (OSTI)

    Zhang, W.; Liu, X. [Comalco Research Centre, Thomastown, Victoria (Australia); McMaster, P.; Taylor, M. [New Zealand Aluminium Smelters Ltd., Invercargill (New Zealand)

    1996-10-01T23:59:59.000Z

    Modeling of impurity balance for an aluminum smelter was conducted. Major impurity streams were sampled and analyzed for impurity concentrations. A flowsheet model was developed and validated using measured data. The purpose of the modeling was to examine the effects of a change from primary to secondary alumina on metal purity and to determine operational strategies to minimize the impact on high purity metal production in the upgrade of the smelter. The impurity partition for cell groups under different operating conditions was determined. Results suggest that production of high purity metal is highly related to the cell operating characteristics. The understanding gained has assisted the design of operating strategies to produce high purity metal from secondary alumina.

  15. SINGLE ELEMENT TEST PREDICTIONS FOR STRESS-STRAIN BEHAVIOR OF PANKI FLY-ASH

    E-Print Network [OSTI]

    Prashant, Amit

    : Fly-ash is a waste product produced by burning of coal at thermal power plants. It is often used. Introduction Fly-ash is a fine powdery material, produced by burning of coal at thermal power plants. Fly-ash need to dispose fly-ash from these ponds. Fly-ash is often used as structural fill in order to dispose

  16. Impurity Radiation from the LHCD Launcher During Operation in JET and Investigation of Launcher Damage

    E-Print Network [OSTI]

    Impurity Radiation from the LHCD Launcher During Operation in JET and Investigation of Launcher Damage

  17. Studies of Impurity Deposition/Implantation in JET Divertor Tiles using SIMS and Ion Beam Techniques

    E-Print Network [OSTI]

    Studies of Impurity Deposition/Implantation in JET Divertor Tiles using SIMS and Ion Beam Techniques

  18. JV Task 120 - Coal Ash Resources Research Consortium Research

    SciTech Connect (OSTI)

    Debra Pflughoeft-Hassett; Loreal Heebink; David Hassett; Bruce Dockter; Kurt Eylands; Tera Buckley; Erick Zacher

    2009-03-28T23:59:59.000Z

    The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') is the core coal combustion product (CCP) research group at the Energy & Environmental Research Center (EERC). CARRC focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of CCPs. CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCP utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program, which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCP performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 2007 to 2009 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCPs. The tasks were included in four categories: (1) Environmental Evaluations of CCPs; (2) Evaluation of Impacts on CCPs from Emission Controls; (3) Construction and Product-Related Activities; and (4) Technology Transfer and Maintenance Tasks. All tasks are designed to work toward achieving the CARRC overall goal and supporting objectives. The various tasks are coordinated in order to provide broad and useful technical data for CARRC members. Special projects provide an opportunity for non-CARRC members to sponsor specific research or technology transfer consistent with CARRC goals. This report covers CARRC activities from January 2007 through March 2009. These activities have been reported in CARRC Annual Reports and in member meetings over the past 2 years. CARRC continues to work with industry and various government agencies with its research, development, demonstration, and promotional activities nearing completion at the time of submission of this report. CARRC expects to continue its service to the coal ash industry in 2009 and beyond to work toward the common goal of advancing coal ash utilization by solving CCP-related technical issues and promoting the environmentally safe, technically sound, and economically viable management of these complex and changing materials.

  19. Impurity control and corrosion resistance of magnesium-aluminum alloy

    SciTech Connect (OSTI)

    Liu, M. [GM China Lab] [GM China Lab; Song, GuangLing [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The corrosion resistance of magnesium alloys is very sensitive to the contents of impurity elements such as iron. In this study, a series of diecast AXJ530 magnesium alloy samples were prepared with additions of Mn and Fe. Through a comprehensive phase diagram calculation and corrosion evaluation, the mechanisms for the tolerance limit of Fe in magnesium alloy are discussed. This adds a new dimension to control the alloying impurity in terms of alloying composition design and casting conditions.

  20. Structure and vibrations of different charge Ge impurity in ?-quartz

    SciTech Connect (OSTI)

    Kislov, A. N., E-mail: a.n.kislov@urfu.ru; Mikhailovich, A. P., E-mail: a.n.kislov@urfu.ru; Zatsepin, A. F., E-mail: a.n.kislov@urfu.ru [Ural Federal University, 19 Mira St., Yekaterinburg, 620002 (Russian Federation)

    2014-10-21T23:59:59.000Z

    Atomic structure and localized vibrations of ??SiO{sub 2}:Ge are studied using computer modeling techniques. The simulation was carried out by the lattice dynamics calculation of the local density of vibrational states. Local structures parameters are calculated, localized symmetrized vibrations frequency caused by Ge impurity in different charge states are defined. The movements of atoms located near Ge impurity are analyzed and their contribution into localized vibrations of different type is evaluated.

  1. Selenium(IV) and (VI) sorption by soils surrounding fly ash management facilities

    SciTech Connect (OSTI)

    Hyun, S.; Burns, P.E.; Murarka, I.; Lee, L.S. [Purdue University, West Lafayette, IN (United States)

    2006-11-15T23:59:59.000Z

    Leachate derived from unlined coal ash disposal facilities is one of the most significant anthropogenic sources of selenium to the environment. To establish a practical framework for predicting transport of selenium in ash leachate, sorption of Se(IV) and Se(VI) from 1 mM CaSO{sub 4} was measured for 18 soils obtained down-gradient from three ash landfill sites and evaluated with respect to several soil properties. Furthermore, soil attenuation from lab-generated ash leachate and the effect of Ca{sup 2+} and SO{sub 4}{sup 2-} concentrations as well as pH on both Se(IV) and Se(VI) was quantified for a subset of soils. For both Se(IV) and Se(VI), pH combined with either percentage clay or dithionite-citrate-bicarbonate (DCB)-extractable Fe described {gt} 80% of the differences in sorption across all soils, yielding an easy approach for making initial predictions regarding site-specific selenium transport to sensitive water bodies. Se(IV) consistently exhibited an order of magnitude greater sorption than Se(VI). Selenium sorption was highest at lower pH values, with Se(IV) sorption decreasing at pH values above 6, whereas Se(VI) decreased over the entire pH range (2.5-10). Using these pH adsorption envelopes, the likely effect of ash leachate-induced changes in soil pore water pH with time on selenium attenuation by down gradient soils can be predicted. Selenium sorption increased with increasing Ca{sup 2+} concentrations while SO{sub 4}2- suppressed sorption well above enhancements by Ca{sup 2+}. Soil attenuation of selenium from ash leachates agreed well with sorption measured from 1 mM CaSO{sub 4}, indicating that 1 mM CaSO{sub 4} is a reasonable synthetic leachate for assessing selenium behavior at ash landfill sites.

  2. Mercury capture by distinct fly ash carbon forms

    SciTech Connect (OSTI)

    Hower, J.C.; Maroto-Valer, M.M.; Taulbee, D.N.; Sakulpitakphon, T.

    1999-07-01T23:59:59.000Z

    Carbon was separated from the fly ash from a Kentucky power plant using density gradient centrifugation. Using a lithium heterolpolytungstate high-density media, relative concentrations of inertinite (up to 85% vol.), isotropic carbon (up to 79% vol.), and anisotropic carbon (up to 76% vol.) were isolated from the original fly ash. Mercury concentration was lowest in the parent fly ash (which contains non-carbon components); followed by inertinite, isotropic coke, mixed isotropic-anisotropic coke fraction, and, with the highest concentration, the anisotropic coke concentrate. The latter order corresponds to the increase in BET surface area of the fly ash carbons. Previous studies have demonstrated the capture of mercury by fly ash carbon. This study confirms prior work demonstrating the varying role of carbon types in the capture, implying that variability in the carbon content influences the amount of mercury retained on the fly ash.

  3. Determination of Ash in Biomass: Laboratory Analytical Procedure...

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

    Ash in Biomass Laboratory Analytical Procedure (LAP) Issue Date: 7172005 A. Sluiter, B. Hames, R. Ruiz, C. Scarlata, J. Sluiter, and D. Templeton Technical Report NREL...

  4. Kinetics of beneficiated fly ash by carbon burnout

    SciTech Connect (OSTI)

    Okoh, J.M.; Dodoo, J.N.D.; Diaz, A. [Univ. of Maryland Eastern Shore, Princess Anne, MD (United States). Dept. of Natural Sciences; Ferguson, W.; Udinskey, J.R. Jr.; Christiana, G.A. [Delmarva Power, Wilmington, DE (United States)

    1997-12-31T23:59:59.000Z

    The presence of carbon in fly ash requires an increase in the dosage of the air-entraining admixture for concrete mix, and may cause the admixture to lose efficiency. Specifying authorities for the concrete producers have set maximum allowable levels of residual carbon. These levels are the so called Loss On Ignition (LOI). The concrete producers` day-to-day purchasing decisions sets the LOI at 4%. The objective of the project is to investigate the kinetics of oxidation of residual carbon present in coal fly ash as a possible first step toward producing low-carbon fly ash from high-carbon, low quality fly ash.

  5. ash transportation distance: Topics by E-print Network

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

    ash 1. Halima Hadiahmetovi?; D. D. Sarajevo; M. Sc; Raza Sunulahpai?; Bosnia Herzegovina 4 Dimensional contraction via Markov transportation distance Francois...

  6. Data Summary Report for Hanford Site Coal Ash Characterization

    SciTech Connect (OSTI)

    Sulloway, H. M.

    2012-03-06T23:59:59.000Z

    The purpose of this report is to present data and findings from sampling and analysis of five distinct areas of coal ash within the Hanford Site River Corridor

  7. ash aqueous carbonation: Topics by E-print Network

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

    carbon content, specific surface area Aydilek, Ahmet 3 Issues with the Use of Fly Ash for Carbon Sequestration A.V. Palumbo1* Environmental Management and Restoration Websites...

  8. alkaline coal ash: Topics by E-print Network

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

    from pulverized coal pulverized-coal-fired furnaces, cyclone furnaces, or advanced clean-coal technology furnaces. The ash collected from pulverized-coal-fired furnaces is fly...

  9. Detailed Characterization of Lubricant-Derived Ash-Related Species...

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

    Species in the Ring Pack and Ash Emissions and Their Dependence on Crankcase Oil Properties Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy...

  10. The variability of fly ash and its effects on selected properties of fresh Portland cement/fly ash mortars

    E-Print Network [OSTI]

    McKerall, William Carlton

    1980-01-01T23:59:59.000Z

    the needed quality control of concrete . Another source of concern results from the recent development of lignite and sub-bituminous coal as fuel sources. The ash produced from these coals is of a different chemical composition than traditional bituminous... 50 percent to greater than 200 percent of a control test. An exhaustive literature review has revealed neglig1ble information concerning the PAI of sub- b1tuminous and lignite ashes. Research is greatly needed to determine the ash properties...

  11. Arsenic remediation of drinking water using iron-oxide coated coal bottom ash

    E-Print Network [OSTI]

    MATHIEU, JOHANNA L.

    2010-01-01T23:59:59.000Z

    using Iron-oxide Coated Coal Ash. In Arsenic Contaminationwater using  iron?oxide coated coal bottom ash  Johanna L.  using iron-oxide coated coal bottom ash JOHANNA L. MATHIEU

  12. E-Print Network 3.0 - ash related problems Sample Search Results

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

    ash related problems Page: << < 1 2 3 4 5 > >> 1 By-Products Utilization Summary: of clean coal ash will increase. Finding practical solutions to this "ash problem" is essential...

  13. Utilization of Ash Fractions from Alternative Biofuels used in Power Plants

    E-Print Network [OSTI]

    Utilization of Ash Fractions from Alternative Biofuels used in Power Plants PSO Project No. 6356 July 2008 Renewable Energy and Transport #12;2 Utilization of Ash Fractions from Alternative Biofuels)...............................................................................7 2. Production of Ash Products from Mixed Biofuels

  14. Cell Ashing for Trace Element Analysis: A New Approach Based on Ultraviolet/Ozone

    E-Print Network [OSTI]

    Gilbert, Pupa Gelsomina De Stasio

    : synchrotron spectromicroscopy; micro- chemical analysis; MEPHISTO; ashing; incineration; trace element. Ashing ashing is based on high-temperature incineration or on the exposure to oxygen plasma (1­ 4). We adopted

  15. E-Print Network 3.0 - ash quarterly technical Sample Search Results

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

    Utilization Summary: Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  16. E-Print Network 3.0 - ash based geopolymer Sample Search Results

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

    Utilization Summary: . CHARACTERIZATION AND APPLICATION OF CLASS F FLY ASH AND CLEAN-COAL ASH FOR CEMENT-BASED MATERIALS 2 The major... large amounts of conventional or...

  17. E-Print Network 3.0 - ash Sample Search Results

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

    Utilization Summary: Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  18. E-Print Network 3.0 - ash penurunan kadar Sample Search Results

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

    Utilization Summary: Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  19. E-Print Network 3.0 - ash paving demonstration Sample Search...

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

    AND DEMONSTRATION... Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  20. E-Print Network 3.0 - ashes Sample Search Results

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

    Utilization Summary: Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  1. E-Print Network 3.0 - ash ahto lobjakas Sample Search Results

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

    Utilization Summary: Center for By-Products Utilization RECENT ADVANCES IN RECYCLING CLEAN- COAL ASH By Tarun R. Naik... -Strength Materials (CLSM); 232, Fly Ash and Natural...

  2. E-Print Network 3.0 - ash based gepolymer Sample Search Results

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

    Utilization Summary: . CHARACTERIZATION AND APPLICATION OF CLASS F FLY ASH AND CLEAN-COAL ASH FOR CEMENT-BASED MATERIALS 2 The major... large amounts of conventional or...

  3. Impurity control studies using SOL flow in DIII-D

    SciTech Connect (OSTI)

    Wade, M.R.; Hogan, J.T.; Isler, R.C. [Oak Ridge National Lab., TN (United States)] [and others

    1998-11-01T23:59:59.000Z

    Experiments on DIII-D have demonstrated the efficacy of using induced scrape-off-layer (SOL) flow to preferentially enrich impurities in the divertor plasma. This SOL flow is produced through simultaneous deuterium gas injection at the midplane and divertor exhaust. Using this SOL flow, an improvement in enrichment (defined as the ratio of impurity fraction in the divertor to that in the plasma core) has been observed for all impurities in trace-level experiments (i.e., impurity level is non-perturbative), with the degree of improvement increasing with impurity atomic number. In the case of argon, exhaust gas enrichment using a modest SOL flow is as high as 17. Using this induced SOL flow technique and argon injection, radiative ELMing H-mode plasmas have been produced that combine high radiation losses (P{sub rad}/P{sub input} > 70%), low core fuel dilution (Z{sub eff} < 1.9), and good core confinement ({tau}{sub E} > 1.0 {tau}{sub E},ITER93H).

  4. EFFECT OF FUEL IMPURITIES ON FUEL CELL PERFORMANCE AND DURABILITY

    SciTech Connect (OSTI)

    Colon-Mercado, H.

    2010-09-28T23:59:59.000Z

    A fuel cell is an electrochemical energy conversion device that produces electricity during the combination of hydrogen and oxygen to produce water. Proton exchange membranes fuel cells are favored for portable applications as well as stationary ones due to their high power density, low operating temperature, and low corrosion of components. In real life operation, the use of pure fuel and oxidant gases results in an impractical system. A more realistic and cost efficient approach is the use of air as an oxidant gas and hydrogen from hydrogen carriers (i.e., ammonia, hydrocarbons, hydrides). However, trace impurities arising from different hydrogen sources and production increases the degradation of the fuel cell. These impurities include carbon monoxide, ammonia, sulfur, hydrocarbons, and halogen compounds. The International Organization for Standardization (ISO) has set maximum limits for trace impurities in the hydrogen stream; however fuel cell data is needed to validate the assumption that at those levels the impurities will cause no degradation. This report summarizes the effect of selected contaminants tested at SRNL at ISO levels. Runs at ISO proposed concentration levels show that model hydrocarbon compound such as tetrahydrofuran can cause serious degradation. However, the degradation is only temporary as when the impurity is removed from the hydrogen stream the performance completely recovers. Other molecules at the ISO concentration levels such as ammonia don't show effects on the fuel cell performance. On the other hand carbon monoxide and perchloroethylene shows major degradation and the system can only be recovered by following recovery procedures.

  5. IN HARM'S WAY: Lack Of Federal Coal Ash

    E-Print Network [OSTI]

    Short, Daniel

    IN HARM'S WAY: Lack Of Federal Coal Ash Regulations Endangers Americans And Their Environment 2010 Thirty-nine New Damage Cases of Contamination from Improperly Disposed Coal Combustion Waste, Editor and Contributing Author #12;IN HARM'S WAY: Lack of Federal Coal Ash Regulations Endangers

  6. Process for the recovery of alumina from fly ash

    DOE Patents [OSTI]

    Murtha, M.J.

    1983-08-09T23:59:59.000Z

    An improvement in the lime-sinter process for recovering alumina from pulverized coal fly ash is disclosed. The addition of from 2 to 10 weight percent carbon and sulfur to the fly ash-calcium carbonate mixture increase alumina recovery at lower sintering temperatures.

  7. Biological impact studies of the Faulkner ash site

    SciTech Connect (OSTI)

    Klose, P.N.; Potera, G.T.

    1984-08-01T23:59:59.000Z

    The Potomac Electric Power Company (PEPCO) has operated the Faulkner coal ash storage facility in southern Charles County, Maryland since 1970. This site handles all the coal ash produced at the nearby Morgantown Generating Stations. Environmental Resources Management, Inc. (ERM) produced an earlier report (Simek, et al., 1983) for PPSP entitled, Environmental Aspects of the Faulkner Ash Site. That report presented a compilation of existing data and newly-generated field information on the ash site and its influence on the local environment. Several questions remained as a result of the analyses carried out for the above study. These were: (a) Are trees downgradient of the site accumulating metals associated with the ash. (b) Is Zekiah Swamp Run being affected by dissolved or precipitated metals. (c) Are invertebrates in Zekiah Swamp Run accumulating metals from the ash site. The studies described herein present data on each of the three questions. Results indicate that no adverse effects on water quality, invertebrates, or trees are occurring. Elevated levels of aluminum, cadmium, and manganese were found throughout the watershed, both above and below the ash site, but no relationship to the ash site could be established.

  8. STRATEGIES AND TECHNOLOGY FOR MANAGING HIGH-CARBON ASH

    SciTech Connect (OSTI)

    Robert Hurt; Eric Suuberg; John Veranth; Xu Chen

    2003-05-20T23:59:59.000Z

    The overall objective of the present project is to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific research issues to be addressed include: (1) the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; (2) the effect of various low-NOx firing modes on ash properties and adsorptivity; and (3) the kinetics and mechanism of ash ozonation. This data will provide scientific and engineering support of the ongoing process development activities. During this fourth project period we completed the characterization of ozone-treated carbon surfaces and wrote a comprehensive report on the mechanism through which ozone suppresses the adsorption of concrete surfactants.

  9. STRATEGIES AND TECHNOLOGY FOR MANAGING HIGH-CARBON ASH

    SciTech Connect (OSTI)

    Robert Hurt; Eric Suuberg; John Veranth; Xu Chen

    2002-09-10T23:59:59.000Z

    The overall objective of the present project is to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific research issues to be addressed include: (1) the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; (2) the effect of various low-NOx firing modes on ash properties and adsorptivity; and (3) the kinetics and mechanism of ash ozonation. This data will provide scientific and engineering support of the ongoing process development activities. During this fourth project period we completed the characterization of ozone-treated carbon surfaces and wrote a comprehensive report on the mechanism through which ozone suppresses the adsorption of concrete surfactants.

  10. Volcanic ash in feed coal and its influence on coal combustion products

    SciTech Connect (OSTI)

    Brownfield, M.E.; Affolter, R.H.; Cathcart, J.D.; Brownfield, I.K.; Hower, J.C.; Stricker, G.D.; O'Connor, J.T.

    2000-07-01T23:59:59.000Z

    The US Geological Survey and the University of Kentucky Center for Applied Energy Research are collaborating with an Indiana Utility to determine the physical and chemical properties of feed coal and coal combustion products (CCPs) from a coal-fired power plant. The plant utilizes a low-sulfur (.23--.47 weight percent S) coal from the Powder River Basin, Wyoming. Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) analysis of feed coal samples identified two mineral suites. A primary suite (not authigenic) consisting of quartz (detrital and volcanic beta-form grains), biotite, and minor zircon and a secondary authigenic mineral suite containing calcite, alumino-phosphates (crandallite and gorceixite), kaolinite, quartz, anatase, barite, and pyrite. The authigenic minerals are attributed to air-fall and reworked volcanic ash that was deposited in peat-forming mires. The Powder River Basin feed coals contain higher amounts of Ba, Ca, Mg, Na, Sr, and P compared to other analyzed eastern coals. These elements are associated with alumino-phosphate, biotite, calcite, and clay minerals. The element associations are indicative of coal that incorporated volcanic ash during deposition. XRD analysis of CCPs revealed a predominance of glass, perovskite, lime, gehlenite, quartz, and phosphates with minor amounts of periclase, anhydrite, hematite, and spinel group minerals in the fly ash; and quartz, plagioclase (albite and anorthite), pyroxene (augite and fassaite), rhodonite, and akermanite in the bottom ash. Microprobe and SEM analysis of fly ash samples revealed quartz, zircon, monazite, euhedral laths of corundum with merrillite, hematite, dendritic spinels/ferrites, and rounded grains of wollastonite with periclase. The abundant Ca and Mg mineral phases in the fly ashes are related to the presence of carbonate, clay, and phosphate minerals in the feed coal. The Ca- and Mg-rich mineral phases in the CCPs can be attributed to volcanic minerals deposited in the peat-forming mire. Dissolution and alteration of these minerals occurred either in the peat-forming sate or during coalification/diagenesis contributing to the authigenic mineral suite. Additionally, detrital mineral input and epigenetic ground-water flow may have affected the geochemistry of the feed coal.

  11. COAL-FIRED UTILITY BOILERS: SOLVING ASH DEPOSITION PROBLEMS

    SciTech Connect (OSTI)

    Christopher J. Zygarlicke; Donald P. McCollor; Steven A. Benson; Jay R. Gunderson

    2001-04-01T23:59:59.000Z

    The accumulation of slagging and fouling ash deposits in utility boilers has been a source of aggravation for coal-fired boiler operators for over a century. Many new developments in analytical, modeling, and combustion testing methods in the past 20 years have made it possible to identify root causes of ash deposition. A concise and comprehensive guidelines document has been assembled for solving ash deposition as related to coal-fired utility boilers. While this report accurately captures the current state of knowledge in ash deposition, note that substantial research and development is under way to more completely understand and mitigate slagging and fouling. Thus, while comprehensive, this document carries the title ''interim,'' with the idea that future work will provide additional insight. Primary target audiences include utility operators and engineers who face plant inefficiencies and significant operational and maintenance costs that are associated with ash deposition problems. Pulverized and cyclone-fired coal boilers are addressed specifically, although many of the diagnostics and solutions apply to other boiler types. Logic diagrams, ash deposit types, and boiler symptoms of ash deposition are used to aid the user in identifying an ash deposition problem, diagnosing and verifying root causes, determining remedial measures to alleviate or eliminate the problem, and then monitoring the situation to verify that the problem has been solved. In addition to a step-by-step method for identifying and remediating ash deposition problems, this guideline document (Appendix A) provides descriptions of analytical techniques for diagnostic testing and gives extensive fundamental and practical literature references and addresses of organizations that can provide help in alleviating ash deposition problems.

  12. Power balance and characterization of impurities in the Maryland Spheromak

    SciTech Connect (OSTI)

    Cote, C.

    1993-12-31T23:59:59.000Z

    The Maryland Spheromak is a medium size magnetically confined plasma of toroidal shape. Low T{sub e} and higher n{sub e} than expected contribute to produce a radiation dominated short-lived spheromak configuration. A pyroelectric radiation detector and a VUV spectrometer have been used for space and time-resolved measurements of radiated power and impurity line emission. Results from the bolometry and VUV spectroscopy diagnostics have been combined to give the absolute concentrations of the major impurity species together with the electron temperature. The large amount of oxygen and nitrogen ions in the plasma very early in the discharge is seen to be directly responsible for the abnormally high electron density. The dominant power loss mechanisms are found to be radiation (from impurity line emission) and electron convection to the end walls during the formation phase of the spheromak configuration, and radiation only during the decay phase.

  13. Giant g-factors of natural impurities in synthetic quartz

    SciTech Connect (OSTI)

    Goryachev, Maxim; Farr, Warrick G.; Tobar, Michael E., E-mail: michael.tobar@uwa.edu.au [ARC Centre of Excellence for Engineered Quantum Systems, University of Western Australia, 35 Stirling Highway, Crawley WA 6009 (Australia)

    2013-12-23T23:59:59.000Z

    We report the observation of g-factors of natural paramagnetic impurities in a pure synthetic quartz crystal at milli-Kelvin temperatures. Measurements are made by performing spectroscopy using multiple high-Q whispering gallery modes sustained in the crystal. Extreme sensitivity of the method at low temperatures allows the determination of natural residual impurities introduced during the crystal growth. We observe g-factors that significantly differ from integer multiples of the electron g-factor in vacuum, and with values of up to 7.6, which reveals much stronger coupling between impurities and the crystal lattice than in previous studies. Both substitutional and interstitial ions are proposed as candidates for the observed interactions.

  14. Removal of fluoride impurities from UF/sub 6/ gas

    DOE Patents [OSTI]

    Beitz, J.V.

    1984-01-06T23:59:59.000Z

    A method of purifying a UF/sub 6/ gas stream containing one or more metal fluoride impurities composed of a transuranic metal, transition metal or mixtures thereof, is carried out by contacting the gas stream with a bed of UF/sub 5/ in a reaction vessel under conditions where at least one impurity reacts with the UF/sub 5/ to form a nongaseous product and a treated gas stream, and removing the treated gas stream from contact with the bed. The nongaseous products are subsequently removed in a reaction with an active fluorine affording agent to form a gaseous impurity which is removed from the reaction vessel. The bed of UF/sub 5/ is formed by the reduction of UF/sub 6/ in the presence of uv light. One embodiment of the reaction vessel includes a plurality of uv light sources as tubes on which UF/sub 5/ is formed. 2 figures.

  15. Fluidization characteristics of power-plant fly ashes and fly ash-charcoal mixtures. [MS Thesis; 40 references

    SciTech Connect (OSTI)

    Nguyen, C.T.

    1980-03-01T23:59:59.000Z

    As a part of the continuing research on aluminum recovery from fly ash by HiChlor process, a plexiglass fluidization column system was constructed for measurement of fluidization parameters for power-plant fly ashes and fly ash-charcoal mixtures. Several bituminous and subbituminous coal fly ashes were tested and large differences in fluidization characteristics were observed. Fly ashes which were mechanically collected fluidized uniformly at low gas flow rates. Most fly ashes which were electrostatically precipitated exhibited channeling tendency and did not fluidize uniformly. Fluidization characteristics of electrostatically collected ashes improve when the finely divided charcoal powder is added to the mixture. The fluidization of the mixture was aided initially by a mechanical stirrer. Once the fluidization had succeeded, the beds were ready to fluidize without the assistance of a mechanical action. Smooth fluidization and large bed expansion were usually observed. The effects of charcoal size and aspect ratio on fluidization characteristics of the mixtures were also investigated. Fluidization characteristics of a fly ash-coal mixture were tested. The mixture fluidized only after being oven-dried for a few days.

  16. Toxicity mitigation and solidification of municipal solid waste incinerator fly ash using alkaline activated coal ash

    SciTech Connect (OSTI)

    Ivan Diaz-Loya, E. [Alternative Cementitious Binders Laboratory (ACBL), Department of Civil Engineering, Louisiana Tech University, Ruston, LA 71272 (United States); Allouche, Erez N., E-mail: allouche@latech.edu [Alternative Cementitious Binders Laboratory (ACBL), Department of Civil Engineering, Louisiana Tech University, Ruston, LA 71272 (United States); Eklund, Sven; Joshi, Anupam R. [Department of Chemistry, Louisiana Tech University, Ruston, LA 71272 (United States); Kupwade-Patil, Kunal [Alternative Cementitious Binders Laboratory (ACBL), Department of Civil Engineering, Louisiana Tech University, Ruston, LA 71272 (United States)

    2012-08-15T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer Incinerator fly ash (IFA) is added to an alkali activated coal fly ash (CFA) matrix. Black-Right-Pointing-Pointer Means of stabilizing the incinerator ash for use in construction applications. Black-Right-Pointing-Pointer Concrete made from IFA, CFA and IFA-CFA mixes was chemically characterized. Black-Right-Pointing-Pointer Environmentally friendly solution to IFA disposal by reducing its toxicity levels. - Abstract: Municipal solid waste (MSW) incineration is a common and effective practice to reduce the volume of solid waste in urban areas. However, the byproduct of this process is a fly ash (IFA), which contains large quantities of toxic contaminants. The purpose of this research study was to analyze the chemical, physical and mechanical behaviors resulting from the gradual introduction of IFA to an alkaline activated coal fly ash (CFA) matrix, as a mean of stabilizing the incinerator ash for use in industrial construction applications, where human exposure potential is limited. IFA and CFA were analyzed via X-ray fluorescence (XRF), X-ray diffraction (XRD) and Inductive coupled plasma (ICP) to obtain a full chemical analysis of the samples, its crystallographic characteristics and a detailed count of the eight heavy metals contemplated in US Title 40 of the Code of Federal Regulations (40 CFR). The particle size distribution of IFA and CFA was also recorded. EPA's Toxicity Characteristic Leaching Procedure (TCLP) was followed to monitor the leachability of the contaminants before and after the activation. Also images obtained via Scanning Electron Microscopy (SEM), before and after the activation, are presented. Concrete made from IFA, CFA and IFA-CFA mixes was subjected to a full mechanical characterization; tests include compressive strength, flexural strength, elastic modulus, Poisson's ratio and setting time. The leachable heavy metal contents (except for Se) were below the maximum allowable limits and in many cases even below the reporting limit. The leachable Chromium was reduced from 0.153 down to 0.0045 mg/L, Arsenic from 0.256 down to 0.132 mg/L, Selenium from 1.05 down to 0.29 mg/L, Silver from 0.011 down to .001 mg/L, Barium from 2.06 down to 0.314 mg/L and Mercury from 0.007 down to 0.001 mg/L. Although the leachable Cd exhibited an increase from 0.49 up to 0.805 mg/L and Pd from 0.002 up to 0.029 mg/L, these were well below the maximum limits of 1.00 and 5.00 mg/L, respectively.

  17. INTRODUCTION Portland cement concrete (PCC) is the world's most versatile and utilized construction material. Modern concrete consists of six

    E-Print Network [OSTI]

    Harms, Kyle E.

    INTRODUCTION Portland cement concrete (PCC) is the world's most versatile and utilized construction material. Modern concrete consists of six main ingredients: coarse aggregate, sand, portland cement sustainability has risen, engineers have looked to alternative binders such as fly ash, silica fume, slag cement

  18. Impurity Effects on the Nodal Structure of Anisotropic Superconductors

    E-Print Network [OSTI]

    Naoyuki Miyata

    2011-06-21T23:59:59.000Z

    For anisotropic superconductors, the gap function belongs to an irreducible representation of the point group of crystals, which determines the nodal structure of the gap function. Impurity effects on anisotropic superconductors have been treated by the Born or T-matrix approximation by which only a partial sum of the pertutbation series is calculated. Instead, we take into acount all terms of the perturbation series. As a result, we find that the introduction of nonmagnetic impurities does not change the nodal structure in all cases. We also find how to obtain nodes of the gap function and show the list for $O_{h}$, $D_{4h}$, and $D_{6h}$.

  19. Evaluation of Vitrification Processing Step for Rocky Flats Incinerator Ash

    SciTech Connect (OSTI)

    Wigent, W.L.; Luey, J.K.; Scheele, R.D.; Li, H.

    1999-04-08T23:59:59.000Z

    In 1997, Pacific Northwest National Laboratory (PNNL) staff developed a processing option for incinerator ash at the Rocky Flats Environmental Technology Sites (RFETS). This work was performed with support from Los Alamos National Laboratory (LANL) and Safe Sites of Colorado (SSOC). A description of the remediation needs for the RFETS incinerator ash is provided in a report summarizing the recommended processing option for treatment of the ash (Lucy et al. 1998). The recommended process flowsheet involves a calcination pretreatment step to remove carbonaceous material followed by a vitrification processing step for a mixture of glass tit and calcined incinerator ash. Using the calcination pretreatment step to remove carbonaceous material reduced process upsets for the vitrification step, allowed for increased waste loading in the final product, and improved the quality of the final product. Figure 1.1 illustrates the flow sheet for the recommended processing option for treatment of RFETS incinerator ash. In 1998, work at PNNL further developed the recommended flow sheet through a series of studies to better define the vitrification operating parameters and to address secondary processing issues (such as characterizing the offgas species from the calcination process). Because a prototypical rotary calciner was not available for use, studies to evaluate the offgas from the calcination process were performed using a benchtop rotary calciner and laboratory-scale equipment (Lucy et al. 1998). This report focuses on the vitrification process step after ash has been calcined. Testing with full-scale containers was performed using ash surrogates and a muffle furnace similar to that planned for use at RFETS. Small-scale testing was performed using plutonium-bearing incinerator ash to verify performance of the waste form. Ash was not obtained from RFETS because of transportation requirements to calcine the incinerator ash prior to shipment of the material. Because part of PNNL's work was to characterize the ash prior to calcination and to investigate the effect of calcination on product quality, representative material was obtained from LANL. Ash obtained from LANL was selected based on its similarity to that currently stored at RFETS. The plutonium-bearing ashes obtained from LANL are likely from a RFETS incinerator, but the exact origin was not identified.

  20. Mutagenicity and genotoxicity of coal fly ash water leachate

    SciTech Connect (OSTI)

    Chakraborty, R.; Mukherjee, A. [University of Calcutta, Calcutta (India). Dept. of Botany

    2009-03-15T23:59:59.000Z

    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals - sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significantconcentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mu m), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.

  1. Phenolic acids as bioindicators of fly ash deposit revegetation

    SciTech Connect (OSTI)

    L. Djurdjevic; M. Mitrovic; P. Pavlovic; G. Gajic; O. Kostic [Institute for Biological Research 'Sinisa Stankovic,' Belgrade (Serbia and Montenegro). Department of Ecology

    2006-05-15T23:59:59.000Z

    The floristic composition, the abundance, and the cover of pioneer plant species of spontaneously formed plant communities and the content of total phenolics and phenolic acids, as humus constituents, of an ash deposit after 7 years of recultivation were studied. The restoration of both the soil and the vegetation on the ash deposits of the 'Nikola Tesla-A' thermoelectric power plant in Obrenovac (Serbia) is an extremely slow process. Unfavorable physical and chemical characteristics, the toxicity of fly ash, and extreme microclimatic conditions prevented the development of compact plant cover. The abundance and cover of plants increased from the central part of the deposit towards its edges. Festuca rubra L., Crepis setosa Hall., Erigeron canadensis L., Cirsium arvense (L.) Scop., Calamagrostis epigeios (L.) Roth., and Tamarix gallica L. were the most abundant species, thus giving the highest cover. Humus generated during the decomposition process of plant remains represents a completely new product absent in the ash as the starting material. The amount of total phenolics and phenolic acids in fly ash increased from the center of the deposit towards its edges in correlation with the increase in plant abundance and cover. The presence of phenolic acids indicates the ongoing process of humus formation in the ash, in which the most abundant pioneer plants of spontaneously formed plant communities play the main role. Phenolic compounds can serve as reliable bioindicators in an assessment of the success of the recultivation process of thermoelectric power plants' ash deposits.

  2. Research Summary RECOAL: Reintegration of coal ash disposal sites and mitigation

    E-Print Network [OSTI]

    Research Summary RECOAL: Reintegration of coal ash disposal sites and mitigation of pollution being used for coal ash deposits. Pollutants present in the ash can contaminate water resources and soil its research on the thermo-electric plant (TEP) and associated coal ash sites at Tuzla, Bosnia

  3. Close Out Report for the Ash Pit Operable Unit I Area of Concern 2F

    E-Print Network [OSTI]

    I to the early 1950's. The Ash Pits were also used for disposal of coal ash from various buildingsFinal Close Out Report for the Ash Pit Operable Unit I Area of Concern 2F February 5, 2004..................................................................................................2 Figure 1 - Ash Level Verification Borings

  4. Helium Ash Simulation Studies with Divertor Helium Pumping in JET Internal Transport Barrier Discharges

    E-Print Network [OSTI]

    Helium Ash Simulation Studies with Divertor Helium Pumping in JET Internal Transport Barrier Discharges

  5. Dechlorination ability of municipal waste incineration fly ash for polychlorinated phenols

    E-Print Network [OSTI]

    Cirkva, Vladimir

    Dechlorination ability of municipal waste incineration fly ash for polychlorinated phenols Leona incineration fly ash at 200 °C under nitrogen atmosphere. Thermodynamic calculations have been carried out ash produced by municipal waste incineration (MWI) have clearly demonstrated that MWI fly ash can

  6. Respiratory and Reproductive Characteristics of Eastern Mosquitofish (Gambusia holbrooki) Inhabiting a Coal Ash Settling Basin

    E-Print Network [OSTI]

    Hopkins, William A.

    ) Inhabiting a Coal Ash Settling Basin B. P. Staub, W. A. Hopkins, J. Novak, J. D. Congdon Savannah River 2002/Accepted: 29 March 2002 Abstract. Coal fly ash and effluent from coal ash settling basins viable populations in areas contaminated by coal ash. While eastern mosquitofish are present

  7. Hydrometallurgical recovery of germanium from coal gasification fly ash: pilot plant scale evaluation

    SciTech Connect (OSTI)

    Arroyo, F.; Fernandez-Pereira, C.; Olivares, J.; Coca, P. [University of Seville, Seville (Spain)

    2009-04-15T23:59:59.000Z

    In this article, a hydrometallurgical method for the selective recovery of germanium from fly ash (FA) has been tested at pilot plant scale. The pilot plant flowsheet comprised a first stage of water leaching of FA, and a subsequent selective recovery of the germanium from the leachate by solvent extraction method. The solvent extraction method was based on Ge complexation with catechol in an aqueous solution followed by the extraction of the Ge-catechol complex (Ge(C{sub 6}H{sub 4}O{sub 2}){sub 3}{sup 2-}) with an extracting organic reagent (trioctylamine) diluted in an organic solvent (kerosene), followed by the subsequent stripping of the organic extract. The process has been tested on a FA generated in an integrated gasification with combined cycle (IGCC) process. The paper describes the designed 5 kg/h pilot plant and the tests performed on it. Under the operational conditions tested, approximately 50% of germanium could be recovered from FA after a water extraction at room temperature. Regarding the solvent extraction method, the best operational conditions for obtaining a concentrated germanium-bearing solution practically free of impurities were as follows: extraction time equal to 20 min; aqueous phase/organic phase volumetric ratio equal to 5; stripping with 1 M NaOH, stripping time equal to 30 min, and stripping phase/organic phase volumetric ratio equal to 5. 95% of germanium were recovered from water leachates using those conditions.

  8. Key issues of FED/INTOR impurity control system

    SciTech Connect (OSTI)

    Abdou, M.A.

    1982-10-01T23:59:59.000Z

    A key part of the FED/INTOR activity over the past year has focused on examining the critical issues and developing credible physics and engineering solutions for the impurity control system. The primary emphasis of the work was on the edge-region physics, plasma-wall interaction, materials, engineering and magnetic considerations of the poloidal divertor and pump limiter.

  9. PREASYMPTOTIC CHARGE OSCILLATIONS AROUND 3d IMPURITIES IN ALUMINIUM

    E-Print Network [OSTI]

    Boyer, Edmond

    on aluminium based transi- tion metal alloys can be explained in the LSF approxi- mation of the Anderson modelL-87 PREASYMPTOTIC CHARGE OSCILLATIONS AROUND 3d IMPURITIES IN ALUMINIUM V. ZLATI0106 and G. GRÜNER modèle d'Anderson la perturbation de densité électronique autour de certaines impuretés 3d dans l'aluminium

  10. STUDY OF RADIOACTIVE IMPURITIES IN SOLIDS PART ONE : RADIATION CHARACTERISTICS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    285 STUDY OF RADIOACTIVE IMPURITIES IN SOLIDS PART ONE : RADIATION CHARACTERISTICS F. HARTMANN problem of the emission of radiation by radioactive nuclei is usually treated in a very general form for the computation of relaxation and radiofrequency effects. LE JOURNAL DE PHYSIQUE TOME 33, FÃ?VRIER-MARS 1972

  11. Quasilinear Carbon Transport In An Impurity Hole Plasma In LHD

    SciTech Connect (OSTI)

    Mikkelsen, David R. [PPPL; Tanaka, K. [NIFS; Nunami, M. [NIFS; Watanabe, T-H. [Nagoya University; Sugama, H. [NIFS; Yoshinuma, M. [NIFS; Suzuki, Y. [NIFS; Goto, M. [NIFS; Morita, S. [NIFS; Wieland, B. [NIFS; Yamada, I. [NIFS; Yashura, R. [NIFS; Akiyama, T. [NIFS; Pablant, Novimir A. [PPPL

    2014-04-01T23:59:59.000Z

    Comprehensive electrostatic gyrokinetic linear stability calculations for ion-scale microinstabilities in an LHD plasma with an ion-ITB and carbon "impurity hole" are used to make quasilinear estimates of particle flux to explore whether microturbulence can explain the observed outward carbon fluxes that flow "up" the impurity density gradient. The ion temperature is not stationary in the ion-ITB phase of the simulated discharge, during which the core carbon density decreases continuously. To fully sample these varying conditions the calculations are carried out at three radial locations and four times. The plasma parameter inputs are based on experimentally measured profiles of electron and ion temperature, as well as electron and carbon density. The spectroscopic line-average ratio of hydrogen and helium densities is used to set the density of these species. Three ion species (H,He,C) and the electrons are treated kinetically, including collisions. Electron instability drive does enhance the growth rate significantly, but the most unstable modes have characteristics of ion temperature gradient (ITG) modes in all cases. As the carbon density gradient is scanned between the measured value and zero, the quasilinear carbon flux is invariably inward when the carbon density profile is hollow, so turbulent transport due to the instabilities considered here does not explain the observed outward flux of impurities in impurity hole plasmas. The stiffness of the quasilinear ion heat flux is found to be 1.7-2.3, which is lower than several estimates in tokamaks.

  12. Recovery of iron oxide from coal fly ash

    DOE Patents [OSTI]

    Dobbins, Michael S. (Ames, IA); Murtha, Marlyn J. (Ames, IA)

    1983-05-31T23:59:59.000Z

    A high quality iron oxide concentrate, suitable as a feed for blast and electric reduction furnaces is recovered from pulverized coal fly ash. The magnetic portion of the fly ash is separated and treated with a hot strong alkali solution which dissolves most of the silica and alumina in the fly ash, leaving a solid residue and forming a precipitate which is an acid soluble salt of aluminosilicate hydrate. The residue and precipitate are then treated with a strong mineral acid to dissolve the precipitate leaving a solid residue containing at least 90 weight percent iron oxide.

  13. Effect of inactive impurities on the burning of ICF targets

    SciTech Connect (OSTI)

    Gus'kov, S. Yu. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Il'in, D. V.; Sherman, V. E. [St. Petersburg State Engineering Institute (Russian Federation)

    2011-12-15T23:59:59.000Z

    The efficiency of thermonuclear burning of the spherical deuterium-tritium (DT) plasma of inertial confinement fusion (ICF) targets in the presence of low-Z impurities (such as lithium, carbon, or beryllium) with arbitrary concentrations is investigated. The effect of impurities produced due to the mixing of the thermonuclear fuel with the material of the structural elements of the target during its compression on the process of target burning is studied, and the possibility of using solid noncryogenic thermonuclear fuels in ICF targets is analyzed. Analytical dependences of the ignition energy and target thermonuclear gain on the impurity concentration are obtained. The models are constructed for homogeneous and inhomogeneous plasmas for the case in which the burning is initiated in the central heated region of the target and then propagates into the surrounding relatively cold fuel. Two possible configurations of an inhomogeneous plasma, namely, an isobaric configuration formed in the case of spark ignition of the target and an isochoric configuration formed in the case of fast ignition, are considered. The results of numerical simulations of the burning of the DT plasma of ICF targets in a wide range of impurity concentrations are presented. The simulations were performed using the TEPA one-dimensional code, in which the thermonuclear burning kinetics is calculated by the Monte Carlo method. It is shown that the strongest negative effect related to the presence of impurities is an increase in the energy of target ignition. It is substantiated that the most promising solid noncryogenic fuel is DT hydride of beryllium (BeDT). The requirements to the plasma parameters at which BeDT can be used as a fuel in noncryogenic ICF targets are determined. Variants of using noncryogenic targets with a solid thermonuclear fuel are proposed.

  14. Magnetocaloric properties of distilled gadolinium: Effects of structural inhomogeneity and hydrogen impurity

    SciTech Connect (OSTI)

    Burkhanov, G. S.; Kolchugina, N. B.; Chzhan, V. B.; Chistyakov, O. D. [Baikov Institute of Metallurgy and Materials Science RAS, 119991 Moscow (Russian Federation); Tereshina, E. A. [Institute of Physics ASCR, 18221 Prague (Czech Republic); Tereshina, I. S. [Baikov Institute of Metallurgy and Materials Science RAS, 119991 Moscow (Russian Federation); International Laboratory of High Magnetic Fields and Low Temperatures PAS, 53-421 Wroclaw (Poland); Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Politova, G. A. [Baikov Institute of Metallurgy and Materials Science RAS, 119991 Moscow (Russian Federation); International Laboratory of High Magnetic Fields and Low Temperatures PAS, 53-421 Wroclaw (Poland); Badurski, D.; Drulis, H. [Institute of Low Temperature and Structure Research PAS, 50-950 Wroclaw (Poland); Paukov, M.; Havela, L. [Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, 12116 Prague (Czech Republic)

    2014-06-16T23:59:59.000Z

    High-purity Gd prepared by distillation is a structurally inhomogeneous system consisting of needle-shaped crystals of cross section 0.5–2.5??m with near-c-axis orientation embedded in a matrix of nanosized (30–100?nm) grains. By measuring the magnetocaloric effect (MCE) directly, we find that the MCE values differ markedly for the plate-shaped samples cut out of a distillate along and perpendicular to the crystals. The effect of small controlled amounts of impurity (hydrogen) on the properties of distilled Gd is further studied. We observe opposite trends in the MCE response to hydrogen charging with respect to the crystal's orientation within the samples and discuss mechanisms interrelating the unique structural morphology with the impurity behavior. As an overall assessment, the Curie temperatures of ?-GdH{sub x} solid solutions increase from 291?K up to 294?K when increasing hydrogen concentration x from 0 to 0.15. Hydrogenation is found to broaden the ferromagnetic-to-paramagnetic phase transition. Hydrogen-containing specimens demonstrate reversibility of MCE at these temperatures.

  15. Impact of local stacking on the graphene-impurity interaction: theory and experiments

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Impact of local stacking on the graphene-impurity interaction: theory and experiments F. Hiebel, P (Dated: January 16, 2014) We investigate the graphene-impurity interaction problem by combining impurity model and density functional theory (DFT) calculations - techniques. We use graphene on the Si

  16. Recombination effects and impurity segregation at grain boundaries in polycrystalline silicon

    E-Print Network [OSTI]

    Boyer, Edmond

    impurities and GB, the diffusion length dependence on the impurities and microstructure might be described ?ig. 1. - Deviation (%) from the model (Eq. (1)) of the neasured minority carriers diffusion length bonding of impurities at GB could be either of the silicide or oxide type, depending on many experimental

  17. Oxygen impurity and microalloying effect in a Zr-based bulk metallic glass alloy

    E-Print Network [OSTI]

    Pennycook, Steve

    Oxygen impurity and microalloying effect in a Zr-based bulk metallic glass alloy C.T. Liu*, M composition Zr­10 at.%Al­5% Ti­17.9% Cu­14.6% Ni (BAM-11) was used to study the effects of oxygen impurities and microalloying on the microstructure and mechanical properties. Oxygen impurity at a level of 3000 appm

  18. Determination of Total Solids and Ash in Algal Biomass: Laboratory...

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

    Solids and Ash in Algal Biomass Laboratory Analytical Procedure (LAP) Issue Date: December 2, 2013 S. Van Wychen and L. M. L. Laurens Technical Report NRELTP-5100-60956 December...

  19. ash impact sorbent: Topics by E-print Network

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

    of aircraft systems 1. Silicate parti- cles in the ash clouds can enter the engines and melt. In the past Oxford, University of First Page Previous Page 1 2 3 4 5 6 7 8...

  20. altered volcanic ash: Topics by E-print Network

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

    near the volcano. Major eruptions are much rarer. They can eject both ash and gases like sulfur dioxide high into the atmosphere-- 80,000 feet or more. Although much of...

  1. ash upptag av: Topics by E-print Network

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

    19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Issues with the Use of Fly Ash for Carbon Sequestration A.V. Palumbo1* Environmental Management and Restoration Websites...

  2. Compressive strength of concrete and mortar containing fly ash

    DOE Patents [OSTI]

    Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

    1997-01-01T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.

  3. Compressive strength of concrete and mortar containing fly ash

    DOE Patents [OSTI]

    Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

    1997-04-29T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specifications required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.

  4. Compressive strength of concrete and mortar containing fly ash

    DOE Patents [OSTI]

    Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

    1998-01-01T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs.

  5. Compressive strength of concrete and mortar containing fly ash

    DOE Patents [OSTI]

    Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

    1998-12-29T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention includes a method for predicting the compressive strength of such a hardenable mixture, which is very important for planning a project. The invention also relates to hardenable mixtures comprising cement and fly ash which can achieve greater compressive strength than hardenable mixtures containing only concrete over the time period relevant for construction. In a specific embodiment, a formula is provided that accurately predicts compressive strength of concrete containing fly ash out to 180 days. In other specific examples, concrete and mortar containing about 15% to 25% fly ash as a replacement for cement, which are capable of meeting design specification required for building and highway construction, are provided. Such materials can thus significantly reduce construction costs. 33 figs.

  6. ash particle deposition: Topics by E-print Network

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

    coal fly ash by reaction with nitrogen oxides can occur in the smokestack, but with the aging Dutta, Prabir K. 5 Particle deposition in ventilation ducts University of California...

  7. Guide to Using Wood Ash as an Agricultural Soil Amendment

    E-Print Network [OSTI]

    New Hampshire, University of

    from larger commercial sources such as wood-burning biomass plants which produce heat or electricity in the soil. Wood ash is more soluble and reactive than ground limestone, and brings about a Benefits Recycles

  8. ash cenospheres composites: Topics by E-print Network

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

    3 Composite Material Lab., Central Gupta, Nikhil 3 Journal of Composite Materials, July 2006, Vol. 40 no. 13, 1163-1174 1163 Thermal Expansion of AluminumFly Ash...

  9. Studies of fly ash using thermal analysis techniques

    SciTech Connect (OSTI)

    Li, Hanxu; Shen, Xiang-Zhong; Sisk, B. [Western Kentucky Univ., Bowling Green, KY (United States)

    1996-12-31T23:59:59.000Z

    Improved thermoanalytical methods have been developed that are capable of quantitative identification of various components of fly ash from a laboratory-scale fluidized bed combustion system. The thermogravimetric procedure developed can determine quantities of H{sub 2}O, Ca(OH){sub 2}, CaCO{sub 3}, CaSO{sub 4} and carbonaceous matter in fly ash with accuracy comparable to more time-consuming ASTM methods. This procedure is a modification of the Mikhail-Turcotte methods that can accurately analyze bed ash, with higher accuracy regarding the greater amount of carbonaceous matter in fly ash. In addition, in conjunction with FTIR and SEM/EDS analysis, the reduction mechanism of CaSO{sub 4} as CaSO{sub 4} + 4H{sub 2} = CaS + 4H{sub 2}O has been confirmed in this study. This mechanism is important in analyzing and evaluating sulfur capture in fluidized-bed combustion systems.

  10. ash leaching methods: Topics by E-print Network

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

    in individualpyrite grains in Illinois6 coal at levels up 6 coal. The same trace metals were detected in pyrite and clay grains from Pittsburgh 8 coal. Ash Laughlin,...

  11. ash technical progress: Topics by E-print Network

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

    ash from the four 43 Technical Brief CiteSeer Summary: ii iiiFOREWARD The Depleted Uranium Technical Brief is designed to convey available information and knowledge about...

  12. ash corrosion resistant: Topics by E-print Network

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

    date: 02.2008 Start date of the consortium (including the Commission Services) 12;2 Handbook on treatment of coal ash disposal sites Preface 162 Nitration of Benzoapyrene...

  13. Recoverable immobilization of transuranic elements in sulfate ash

    DOE Patents [OSTI]

    Greenhalgh, Wilbur O. (Richland, WA)

    1985-01-01T23:59:59.000Z

    Disclosed is a method of reversibly immobilizing sulfate ash at least about 20% of which is sulfates of transuranic elements. The ash is mixed with a metal which can be aluminum, cerium, samarium, europium, or a mixture thereof, in amounts sufficient to form an alloy with the transuranic elements, plus an additional amount to reduce the transuranic element sulfates to elemental form. Also added to the ash is a fluxing agent in an amount sufficient to lower the percentage of the transuranic element sulfates to about 1% to about 10%. The mixture of the ash, metal, and fluxing agent is heated to a temperature sufficient to melt the fluxing agent and the metal. The mixture is then cooled and the alloy is separated from the remainder of the mixture.

  14. Environmental aspects of the faulkner ash site. Final report

    SciTech Connect (OSTI)

    Simek, E.M.; Hewitt, M.A.; Potera, G.T.

    1983-01-01T23:59:59.000Z

    The Potomac Electric Power Company (PEPCO) has owned and operated the Faulkner coal ash storage facility in southern Charles County, Maryland since 1970. This site was designed and is operated specifically to handle, in an environmentally sound manner, the large quantities of coal ash produced at the nearby Morgantown Generating Station. This report describes the site, its setting, and its interactions with the local environment.

  15. Concordant plutonium-241-americium-241 dating of environmental samples: results from forest fire ash

    SciTech Connect (OSTI)

    Goldstein, Steven J [Los Alamos National Laboratory; Oldham, Warren J [Los Alamos National Laboratory; Murrell, Michael T [Los Alamos National Laboratory; Katzman, Danny [Los Alamos National Laboratory

    2010-12-07T23:59:59.000Z

    We have measured the Pu, {sup 237}Np, {sup 241}Am, and {sup 151}Sm isotopic systematics for a set of forest fire ash samples from various locations in the western U.S. including Montana, Wyoming, Idaho, and New Mexico. The goal of this study is to develop a concordant {sup 241}Pu (t{sub 1/2} = 14.4 y)-{sup 241}Am dating method for environmental collections. Environmental samples often contain mixtures of components including global fallout. There are a number of approaches for subtracting the global fallout component for such samples. One approach is to use {sup 242}/{sup 239}Pu as a normalizing isotope ratio in a three-isotope plot, where this ratio for the nonglobal fallout component can be estimated or assumed to be small. This study investigates a new, complementary method of normalization using the long-lived fission product, {sup 151}Sm (t{sub 1/2} = 90 y). We find that forest fire ash concentrates actinides and fission products with {approx}1E10 atoms {sup 239}Pu/g and {approx}1E8 atoms {sup 151}Sm/g, allowing us to measure these nuclides by mass spectrometric (MIC-TIMS) and radiometric (liquid scintillation counting) methods. The forest fire ash samples are characterized by a western U.S. regional isotopic signature representing varying mixtures of global fallout with a local component from atmospheric testing of nuclear weapons at the Nevada Test Site (NTS). Our results also show that {sup 151}Sm is well correlated with the Pu nuclides in the forest fire ash, suggesting that these nuclides have similar geochemical behavior in the environment. Results of this correlation indicate that the {sup 151}Sm/{sup 239}Pu atom ratio for global fallout is {approx}0.164, in agreement with an independent estimate of 0.165 based on {sup 137}Cs fission yields for atmospheric weapons tests at the NTS. {sup 241}Pu-{sup 241}Am dating of the non-global fallout component in the forest fire ash samples yield ages in the late 1950's-early 1960's, consistent with a peak in NTS weapons testing at that time. The age results for this component are in agreement using both {sup 242}Pu and {sup 151}Sm normalizations, although the errors for the {sup 151}Sm correction are currently larger due to the greater uncertainty of their measurements. Additional efforts to develop a concordant {sup 241}Pu-{sup 241}Am dating method for environmental collections are underway with emphasis on soil cores.

  16. Ash level meter for a fixed-bed coal gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV)

    1984-01-01T23:59:59.000Z

    An ash level meter for a fixed-bed coal gasifier is provided which utilizes the known ash level temperature profile to monitor the ash bed level. A bed stirrer which travels up and down through the extent of the bed ash level is modified by installing thermocouples to measure the bed temperature as the stirrer travels through the stirring cycle. The temperature measurement signals are transmitted to an electronic signal process system by an FM/FM telemetry system. The processing system uses the temperature signals together with an analog stirrer position signal, taken from a position transducer disposed to measure the stirrer position to compute the vertical location of the ash zone upper boundary. The circuit determines the fraction of each total stirrer cycle time the stirrer-derived bed temperature is below a selected set point, multiplies this fraction by the average stirrer signal level, multiplies this result by an appropriate constant and adds another constant such that a 1 to 5 volt signal from the processor corresponds to a 0 to 30 inch span of the ash upper boundary level. Three individual counters in the processor store clock counts that are representative of: (1) the time the stirrer temperature is below the set point (500.degree. F.), (2) the time duration of the corresponding stirrer travel cycle, and (3) the corresponding average stirrer vertical position. The inputs to all three counters are disconnected during any period that the stirrer is stopped, eliminating corruption of the measurement by stirrer stoppage.

  17. STRATEGIES AND TECHNOLOGY FOR MANAGING HIGH-CARBON ASH

    SciTech Connect (OSTI)

    Robert Hurt; Eric Suuberg; John Veranth

    2001-12-26T23:59:59.000Z

    The overall objective of the present project is to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific research issues to be addressed include: the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; the effect of various low-NOx firing modes on ash properties and adsorptivity; and the kinetics and mechanism of ash ozonation. This data will provide scientific and engineering support of the ongoing process development activities. This first project period, experiments were carried out to better understand the fundamental nature of the ozonation effect on ash. Carbon surfaces were characterized by surfactant adsorption, and by X-ray Photoelectron Spectroscopy before and after oxidation, both by air at 440 C and by ozone at room temperature. The results strongly suggest that the beneficial effect of ozonation is in large part due to chemical modification of the carbon surfaces.

  18. STRATEGIES AND TECHNOLOGY FOR MANAGING HIGH-CARBON ASH

    SciTech Connect (OSTI)

    Robert Hurt; Eric Suuberg; John Veranth; Xu Chen; Indrek Kulaots

    2004-02-13T23:59:59.000Z

    The overall objective of the present project was to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific issues addressed included: (1) the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; (2) the effect of various low-NOx firing modes on ash properties and adsorptivity based on pilot-plant studies; and (3) the kinetics and mechanism of ash ozonation. This laboratory data has provided scientific and engineering support and underpinning for parallel process development activities. The development work on the ash ozonation process has now transitioned into a scale-up and commercialization project involving a multi-industry team and scheduled to begin in 2004. This report describes and documents the laboratory and pilot-scale work in the above three areas done at Brown University and the University of Utah during this three-year project.

  19. Ash Reduction of Corn Stover by Mild Hydrothermal Preprocessing

    SciTech Connect (OSTI)

    M. Toufiq Reza; Rachel Emerson; M. Helal Uddin; Garold Gresham; Charles J. Coronella

    2014-04-22T23:59:59.000Z

    Lignocellulosic biomass such as corn stover can contain high ash content, which may act as an inhibitor in downstream conversion processes. Most of the structural ash in biomass is located in the cross-linked structure of lignin, which is mildly reactive in basic solutions. Four organic acids (formic, oxalic, tartaric, and citric) were evaluated for effectiveness in ash reduction, with limited success. Because of sodium citrate’s chelating and basic characteristics, it is effective in ash removal. More than 75 % of structural and 85 % of whole ash was removed from the biomass by treatment with 0.1 g of sodium citrate per gram of biomass at 130 °C and 2.7 bar. FTIR, fiber analysis, and chemical analyses show that cellulose and hemicellulose were unaffected by the treatment. ICP–AES showed that all inorganics measured were reduced within the biomass feedstock, except sodium due to the addition of Na through the treatment. Sodium citrate addition to the preconversion process of corn stover is an effective way to reduced physiological ash content of the feedstock without negatively impacting carbohydrate and lignin content.

  20. Evaluation of Consistent Logical Checkpointing

    E-Print Network [OSTI]

    Kaul, Surbhi

    1995-01-01T23:59:59.000Z

    is cliscussed in more cletail in the next chapter lvhich pr smlts tht val'iations of the consist( nt logical ?heckpointing scheme. Applicatiuu '('('Itl& L's(&r Cu Illnunication The next set of experime!its !s pet fol meri uitli aii application lvith a...

  1. Resonance capture by hydrogenous impurities and losses of ultracold neutrons in solid material traps

    E-Print Network [OSTI]

    G. S. Danilov

    2009-03-03T23:59:59.000Z

    The capture of trapped ultracold neutrons (UCNs) by closed hydrogenous impurities within a solid coating of the trap is discussed as a possible cause of observed anomalously large losses of UCNs in solid material UCN traps. Then significant losses of UCNs arise only if resonances occur in the UCN-impurity scattering amplitude. For a large size impurity, higher partial waves in the UCN-impurity interaction are important, and they are taken into account in the present paper. The method of the calculation is applicable to irregular shape impurities as well. A small distortion of an impurity shape, if it splits the resonance, can increase the UCN losses by a few times. UCN losses in the beryllium trap are calculated assuming they are due to the UCN capture by ice spherical impurities within the coating of the trap walls. Both s- and p-wave resonances contribute significantly to the UCN losses considered. As an example, observed anomalous large UCN losses are achieved if the average radius of the impurity is about 600 Angstroms and the impurity density is about 3*10^{14}/cm^3. A distortion of the spherical shape of the impurity could increase the UCN losses and therefore decrease the impurity density.

  2. Localized states of a semi-infinite zigzag graphene sheet with impurity lines

    SciTech Connect (OSTI)

    Cunha, A. M. C., E-mail: amagno@fisica.ufc.br [Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceara (Brazil); Ahmed, Maher Z. [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada and Physics Department, Faculty of Science, Ain Shams University, Abbsai, Cairo (Egypt); Cottam, M. G., E-mail: cottam@uwo.ca [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada); Filho, R. N. Costa, E-mail: rai@fisica.ufc.br [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada and Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, Campus do Pici, 60455-760 Fortaleza, Ceara (Brazil)

    2014-07-07T23:59:59.000Z

    The localized states of a semi-infinite zigzag graphene sheet are studied using a tight-binding model that allows for the inclusion of either one or two lines of impurities. These impurity lines of atoms are placed in rows labeled as n (n?=?1, 2, 3, …), where n?=?1 is the free edge. The localized defect modes associated with these impurities are studied analytically and numerically within a tridiagonal matrix formalism. For one impurity line, the modes are analyzed according to the position of that line on the sheet, whereas the modes for two impurities are studied also according to their separation and their positions relative to the edge. When an impurity line is located at the edge (n?=?1), it is found that the edge states are modified. When the impurities are positioned away from an edge (n?>?1), additional localized modes are found to occur that may be relatively flat in their dispersion.

  3. Edge Plasma Effects in DIII-D Impurity Seeded Discharges

    SciTech Connect (OSTI)

    Jackson, G.L.; Boedo, J.A.; Lasnier, C. J.; Leonard, A.W.; McKee, G. R.; Murakami, M; Wade, M.R.; Watkins, J.G.; West, W.P.; Whyte, D.G.

    2002-06-01T23:59:59.000Z

    DIII-D, ELMing H-mode radiating mantle discharges have been obtained with electron density near the Greenwald density limit and a large fraction of the input power radiated inside the last closed flux surface, significantly reducing peak divertor heat fluxes. In these ''puff and pump'' discharges, the introduction of argon reduces particle flux to divertor tiles by a factor of 4 while peak heat flux is half of the no impurity value, suggesting that impurity seeding may be a useful control tool to reduce wall heat and particle fluxes in fusion reactors. A robust H-mode transport barrier is maintained and there is little change in the ELM energy or in the ELM frequency.

  4. Effect of surface derived hydrocarbon impurities on Ar plasma properties

    SciTech Connect (OSTI)

    Fox-Lyon, Nick; Oehrlein, Gottlieb S., E-mail: Oehrlein@umd.edu [Department of Materials Science and Engineering and the Institute for Research and Applied Physics, University of Maryland, College Park, MD 20742 (United States); Godyak, Valery [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109-2122 (United States)

    2014-05-15T23:59:59.000Z

    The authors report on Langmuir probe measurements that show that hydrocarbon surfaces in contact with Ar plasma cause changes of electron energy distribution functions due to the flux of hydrogen and carbon atoms released by the surfaces. The authors compare the impact on plasma properties of hydrocarbon species gasified from an etching hydrocarbon surface with injection of gaseous hydrocarbons into Ar plasma. They find that both kinds of hydrocarbon injections decrease electron density and slightly increase electron temperatures of low pressure Ar plasma. For low percentages of impurities (?1% impurity in Ar plasma explored here), surface-derived hydrocarbon species and gas phase injected hydrocarbon molecules cause similar changes of plasma properties for the same number of hydrocarbon molecules injected into Ar with a decrease in electron density of ?4%.

  5. Luminescence from defects and impurity centers in yttrium oxide

    SciTech Connect (OSTI)

    Jahan, M.S.; Cooke, D.W.; Bennett, B.L.; Hults, W.L.; Maez, M.A.; Ott, K.C.; Smith, J.L.

    1989-01-01T23:59:59.000Z

    High-purity (99.999%) Y{sub 2}O{sub 3} powder is used as a starting material for fabricating high-temperature superconductors (HTS), and is frequently found as an unreacted second phase in the final product. We have found that as-received Y{sub 2}O{sub 3} contains Tb{sup 3+} paramagnetic impurity ions as determined by TSL and emission-spectra measurements. Deep luminescence traps (presumably Tb{sup 4+} ions) are formed in Y{sub 2}O{sub 3} when it is exposed to {gamma}-rays, x rays, or fluorescent lights. These deep traps can only be removed by annealing the material to near 1600{degree}C. Given the short coherence length of HTS it is possible that order-of-magnitude variations in the Tb impurity concentration of starting materials may affect the ultimate value of surface resistance (R{sub s}).

  6. A REVIEW OF RECENT IMPURITY MEASUREMENTS OF LANL MATERIAL

    SciTech Connect (OSTI)

    Edwards, T.

    2012-07-12T23:59:59.000Z

    The Applied Computational Engineering and Statistics (ACES) group of the Savannah River National Laboratory (SRNL) was asked to review recent measurements performed by the Los Alamos National Laboratory (LANL) on material from that facility that is being considered for processing through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF) at the Savannah River Site (SRS). There are specification limits for impurities in the feed to the MOX facility: a maximum limit and an exceptional limit. The limits for an impurity apply to the population of concentration values for that impurity for a class of material that is to be processed through MOX. For the purposes of this report, these limits were defined as follows. The concentration of an elemental impurity, expressed as micrograms of the element per gram of plutonium ({micro}g/g Pu), is to be no more than the maximum limit for that element for 98% of the material coming through MOX; that is, 98% of the material processed at MOX is to have a concentration of the given element less than the maximum limit. In addition, the concentration for a given element is to be no more than the exceptional limit for that element for 99.9% of the material processed through MOX. The measurements evaluated as part of this study included LANL blend lots 1 through 29 and cover carbon (C), chlorine (Cl), fluorine (F), nitrogen (N), phosphorous (P), and sulfur (S). Note that all of the measurements for each impurity were below their respective maximum (and obviously, therefore, their exceptional) limits. Thus, there is no immediate concern regarding the LANL material being suitable for processing through MOX. Two approaches were used to investigate the quantiles of the impurity populations. The first approach used was a nonparametric approach. While the results from this approach did not indicate any problems for any of the impurities, there was too little data available to lead to confident statements about satisfying the maximum and exceptional limits. Impurity data from additional random samples of the LANL material would be needed to increase the confidence level associated with the results from a nonparametric approach for investigating the population quantiles of interest. For S, F, and Cl, only a nonparametric approach was used. A second approach, a parametric approach, was attempted for C, P, and N. However, the results for the P and N measurements indicated that each of their respective populations was not well modeled by a normal or by a lognormal distribution. Thus, the conclusions for the P and N populations were those provided by the nonparametric approach. From the parametric approach, the results for C indicated no issue in the LANL material meeting the maximum limit for this element assuming that the measurements for this element follow a lognormal distribution.

  7. Clay formation and metal fixation during weathering of coal fly ash

    SciTech Connect (OSTI)

    Zevenbergen, C.; Bradley, J.P.; Reeuwijk, L.P. Van; Shyam, A.K.; Hjelmar, O.; Comans, R.N.J.

    1999-10-01T23:59:59.000Z

    The enormous and worldwide production of coal fly ash cannot be durably isolated from the weathering cycle, and the weathering characteristics of fly ash must be known to understand the long-term environmental impact. The authors studied the weathering of two coal fly ashes and compared them with published data from weathered volcanic ash, it's closest natural analogue. Both types of ash contain abundant aluminosilicate glass, which alters to noncrystalline clay. However, this study reveals that the kinetics of coal fly ash weathering are more rapid than those of volcanic ash because the higher pH of fresh coal fly ash promotes rapid dissolution of the glass. After about 10 years of weathering, the noncrystalline clay content of coal fly ash is higher than that of 250-year-old volcanic ash. The observed rapid clay formation together with heavy metal fixation imply that the long-term environmental impact of coal fly ash disposal may be less severe and the benefits more pronounced than predicted from previous studies on unweathered ash. Their findings suggest that isolating coal fly ash from the weathering cycle may be counterproductive because, in the long-term under conditions of free drainage, fly ash is converted into fertile soil capable of supporting agriculture.

  8. Consistently violating the non-Gaussian consistency relation

    E-Print Network [OSTI]

    Mooij, Sander; Romano, Antonio E

    2015-01-01T23:59:59.000Z

    Non-attractor models of inflation are characterized by the super-horizon evolution of curvature perturbations, introducing a violation of the non-Gaussian consistency relation between the bispectrum's squeezed limit and the power spectrum's spectral index. In this work we show that the bispectrum's squeezed limit of non-attractor models continues to respect a relation dictated by the evolution of the background. We show how to derive this relation using only symmetry arguments, without ever needing to solve the equations of motion for the perturbations.

  9. "Effects of Impurities on Fuel Cell Performance and Durability"

    E-Print Network [OSTI]

    strategies/means to reduce the impact of these impurities. #12;Previous Research · CO · CO2 · NH3 · H2S. 227 (2002) 231] Extensive poisoning of anode catalyst in PEMFC caused by 50 ppb of H2S due to strong 1-10 ppm Formic Acid 0.1-1 ppm Formaldehyde 5-50 ppb O2 2-20 ppm H2O 2-20 ppm Cl2 20-200 ppb H2S 2

  10. Simple method of impurity injection into tokamak plasmas

    SciTech Connect (OSTI)

    Hildebrandt, D.; Bakos, J.S.; Petravich, G.; Badalec, H.; Jakubka, K.

    1989-04-01T23:59:59.000Z

    Injection of test impurities into the edge plasma of tokamak discharges by erosion probes containing these impurities is described. By applying a short bias pulse to the probe inserted into the sol-plasma, the plasma density and temperature at the probe location can be deduced and the time of injection during the discharge can be controlled. By locating the probe at an appropriate position it is possible to release defined quantities of the material and to influence the fraction which penetrates into the core plasma. The injection of Li into hydrogen discharges of the small-sized tokamaks Castor and MT-1 is demonstrated. The nature of the main erosion process (ion sputtering or arcing) has been found to depend on the radial position of the probe and the probe potential. The lithium amount released by sputtering is determined, while in the case of arcing only an estimate can be given. The temporal evolution and the radial penetration of the Li influx into the plasma have been observed by monitoring the neutral emission line using a grating spectrometer and a CCD camera. In addition, Li transported through the plasma was collected on solid samples. An estimate is given on the fraction of the impurity efflux from the core plasma which is collected on the samples.

  11. Gyrokinetic modelling of stationary electron and impurity profiles in tokamaks

    SciTech Connect (OSTI)

    Skyman, A., E-mail: andreas.skyman@chalmers.se; Tegnered, D., E-mail: tegnered@chalmers.se; Nordman, H., E-mail: hans.nordman@chalmers.se; Strand, P., E-mail: par.strand@chalmers.se [Euratom–VR Association, Department of Earth and Space Sciences, Chalmers University of Technology, SE-412 96 Göteborg (Sweden)

    2014-09-15T23:59:59.000Z

    Particle transport due to Ion Temperature Gradient (ITG)/Trapped Electron Mode (TEM) turbulence is investigated using the gyrokinetic code GENE. Both a reduced quasilinear treatment and nonlinear simulations are performed for typical tokamak parameters corresponding to ITG dominated turbulence. The gyrokinetic results are compared and contrasted with results from a computationally efficient fluid model. A selfconsistent treatment is used, where the stationary local profiles are calculated corresponding to zero particle flux simultaneously for electrons and trace impurities. The scaling of the stationary profiles with magnetic shear, safety factor, electron-to-ion temperature ratio, collisionality, toroidal sheared rotation, plasma ?, triangularity, and elongation is investigated. In addition, the effect of different main ion mass on the zero flux condition is discussed. The electron density gradient can significantly affect the stationary impurity profile scaling. It is therefore expected that a selfconsistent treatment will yield results more comparable to experimental results for parameter scans where the stationary background density profile is sensitive. This is shown to be the case in scans over magnetic shear, collisionality, elongation, and temperature ratio, for which the simultaneous zero flux electron and impurity profiles are calculated. A slight asymmetry between hydrogen, deuterium, and tritium with respect to profile peaking is obtained, in particular, for scans in collisionality and temperature ratio.

  12. Anderson metal-insulator transitions with classical magnetic impurities

    SciTech Connect (OSTI)

    Jung, Daniel [School of Engineering and Science, Jacobs University Bremen gGmbH, Campus Ring 1, 28759 Bremen, Germany and Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Kettemann, Stefan [School of Engineering and Science, Jacobs University Bremen gGmbH,Campus Ring 1, 28759 Bremen, Germany and Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of)

    2014-08-20T23:59:59.000Z

    We study the effects of classical magnetic impurities on the Anderson metal-insulator transition (AMIT) numerically. In particular we find that while a finite concentration of Ising impurities lowers the critical value of the site-diagonal disorder amplitude W{sub c}, in the presence of Heisenberg impurities, W{sub c} is first increased with increasing exchange coupling strength J due to time-reversal symmetry breaking. The resulting scaling with J is compared to analytical predictions by Wegner [1]. The results are obtained numerically, based on a finite-size scaling procedure for the typical density of states [2], which is the geometric average of the local density of states. The latter can efficiently be calculated using the kernel polynomial method [3]. Although still suffering from methodical shortcomings, our method proves to deliver results close to established results for the orthogonal symmetry class [4]. We extend previous approaches [5] by combining the KPM with a finite-size scaling analysis. We also discuss the relevance of our findings for systems like phosphor-doped silicon (Si:P), which are known to exhibit a quantum phase transition from metal to insulator driven by the interplay of both interaction and disorder, accompanied by the presence of a finite concentration of magnetic moments [6].

  13. Metal recovery from fly ash generated from vitrification process for MSW ash

    SciTech Connect (OSTI)

    Izumikawa, Chiaki [Dowa Mining Co. Ltd., Chiyoda, Tokyo (Japan)] [Dowa Mining Co. Ltd., Chiyoda, Tokyo (Japan)

    1996-12-31T23:59:59.000Z

    Metal-bearing wastes have to be carefully treated because heavy metals could be leached out under uncontrolled conditions when disposed of in a landfill. Consequently, heavy metals should be principally recovered and recycled forever. From this standpoint, the author has been trying to develop a technology to recover heavy metals from toxic vitrification fly ash for recycling to smelters. After a number of laboratory-scale experiments, pilot plant tests were successfully carried out and the developed process has been proven to be commercially realized. The main features of the process are that it recovers almost 100% of the heavy metals, simultaneously separating the metals which are recovered in a lead smelter from those in a zinc smelter, and that the output of the process are only metallurgical products recyclable for smelters and the effluent water which can be released into the environment. The process is considered an ideal one for the treatment of toxic fly ash from the viewpoint of not only natural resources but also environmental conservation.

  14. Study on the Volatility of Cesium in Dry Ashing Pretreatment and Dissolution of Ash by Microwave Digestion System - 13331

    SciTech Connect (OSTI)

    Choi, Kwang-Soon; Lee, Chang Heon; Ahn, Hong-Joo; Park, Yong Joon; Song, Kyuseok [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)] [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)

    2013-07-01T23:59:59.000Z

    Based on the regulation of the activity concentration of Cs-137, Co-58, Co-60, Fe-55, Ni-59, Ni-63, Sr-90, Nb-94, and Tc-99, and the total alpha from the radioactive waste acceptance criteria, the measurement of the activity concentration of these nuclides in low and intermediate levels of radioactive waste such as in paper, cotton, vinyl and plastic samples was investigated. A dry ashing method was applied to obtain a concentration effect of the samples. Owing to the temperature dependence of the volatility for cesium, the temperature of 300 to 650 deg. C was examined. It was found that 450 deg. C is the optimum dry ashing temperature. After dry ashing, the produced ash was dissolved with HNO{sub 3}, HCl, and HF by a high-performance microwave digestion system. The ash sample, for the most part, was completely dissolved with 10 mL of HNO{sub 3}, 4 mL of HCl, and 0.25 mL of HF by a high-performance microwave digestion system using a nova high temperature rotor at 250 deg. C for 90 min until reaching 0.2 g. To confirm the reliability of cesium loss after the performance of the dry ashing procedure, a cesium standard solution for AAS and a Cs-137 standard solution for gamma spectrometry were added to a paper towel or a planchet of stainless steel, respectively. Cesium was measured by AAS, ICP-MS, and gamma spectrometry. The volatility of cesium did not occur until 450 deg. C ashing. (authors)

  15. Release of Ammonium and Mercury from NOx Controlled Fly Ash

    SciTech Connect (OSTI)

    Schroeder, K.T.; Cardone, C.R.; Kim, A.G

    2007-07-01T23:59:59.000Z

    One of the goals of the Department of Energy is to increase the reuse of coal utilization byproducts (CUB) to 50% by 2010. This will require both developing new markets and maintaining traditional ones such as the use of fly ash in concrete. However, the addition of pollution control devices can introduce side-effects that affect the marketability of the CUB. Such can be the case when NOx control is achieved using selective catalytic or non-catalytic reduction (SCR or SNCR). Depending on site-specific details, the ammonia slip can cause elevated levels of NH3 in the fly ash. Disposal of ammoniated fly ash can present environmental concerns related to the amount of ammonia that might be released, the amount of water that might become contaminated, and the extent to which metals might be mobilized by the presence of the ammonia. Ammonia retained in fly ash appears to be present as either an ammonium salt or as a chemisorbed species. Mercury in the leachates correlated to neither the amount of leachable ammonium nor to the total amount of Hg in the ash. The strongest correlation was between the decreases in the amount of Hg leached with increased LOI.

  16. Ash bed level control system for a fixed-bed coal gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV); Rotunda, John R. (Fairmont, WV)

    1984-01-01T23:59:59.000Z

    An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate. A grate drive is activated to rotate a grate assembly supporting the ash bed for a period equal to the count down period to maintain the selected ash bed level. In order to avoid grate binding, the controller provides a short base operating duration time each stirrer cycle. If the ash bed level drops below a selected low level or exceeds a selected high level, means are provided to notify the operator.

  17. Non-Destructive X-ray Measurement of Soot, Ash, Washcoat and...

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

    X-ray Measurement of Soot, Ash, Washcoat and Regeneration Damage for DPFs Non-Destructive X-ray Measurement of Soot, Ash, Washcoat and Regeneration Damage for DPFs New commercially...

  18. Geotechnical properties of fly and bottom ash mixtures for use in highway embankments

    SciTech Connect (OSTI)

    Kim, B.; Prezzi, M.; Salgado, R. [Korean Institute for Water & Environment, Taejon (Republic of Korea). Dam Safety Research Center

    2005-07-01T23:59:59.000Z

    Class F fly ash and bottom ash are the solid residue byproducts produced by coal-burning electric utilities. They are usually disposed of together as a waste in utility disposal sites with a typical disposal rate of 80% fly ash and 20% bottom ash. Direct use of these materials in construction projects consuming large volumes of materials, such as highway embankment construction, not only provides a promising solution to the disposal problem, but also an economic alternative to the use of traditional materials. Representative samples of class F fly and bottom ash were collected from two utility power plants in Indiana and tested for their mechanical properties (compaction, permeability, strength, stiffness, and compressibility). Three mixtures of fly and bottom ash with different mixture ratios (i.e., 50, 75, and 100% fly ash content by weight) were prepared for testing. Test results indicated that ash mixtures compare favorably with conventional granular materials.

  19. E-Print Network 3.0 - ashing wet Sample Search Results

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

    Sciences and Ecology 4 By-Products Utilization Summary: A3, containing 20% clean coal ash and 5% wet collected Class F ash had compressive strengths... 0 Center for...

  20. E-Print Network 3.0 - ashing dry Sample Search Results

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

    Shrinkage of Non-Air Entrained HRWRA Concrete -0.05% 0.00% 0.05% 0... NS3, 33% Clean Coal Ash, 5% Class F Fly Ash Fig. 15 - ... Source: Wisconsin-Milwaukee, University of -...

  1. E-Print Network 3.0 - ash material analisis Sample Search Results

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

    was used in this work. An ASTM Class F fly ash... , and N3) were proportioned with clean coal fly ash containing 22% ... Source: Wisconsin-Milwaukee, University of - Department...

  2. E-Print Network 3.0 - alkali-activated fly ash Sample Search...

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

    Engineering ; Materials Science 12 By-Products Utilization Summary: CONTAINING CLEAN-COAL ASH AND CLASS F FLY ASH By Tarun R. Naik, Rudolph N. Kraus, Rafat Siddique... of...

  3. E-Print Network 3.0 - activated fly ash Sample Search Results

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

    Engineering ; Materials Science 9 By-Products Utilization Summary: CONTAINING CLEAN-COAL ASH AND CLASS F FLY ASH By Tarun R. Naik, Rudolph N. Kraus, Rafat Siddique... of...

  4. E-Print Network 3.0 - ashes total contents Sample Search Results

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

    fly ash content for normal concrete... contained fly ash up to a maximum of 35% of clean-coal ... Source: Wisconsin-Milwaukee, University of - Department of Civil Engineering and...

  5. Tephrochronology and Stratigraphy of Eocene and Oligocene Volcanic Ashes of East and Central Texas

    E-Print Network [OSTI]

    Heintz, Mindi

    2013-12-02T23:59:59.000Z

    using neutron activation analysis (NAA) of bulk ash and glass shards, inductively coupled plasma mass spectrometry (ICPMS) of bulk ash, and electron microprobe analysis of both apatite phenocrysts and glass shards to characterize their geochemistry...

  6. In vivo imaging of C. elegans ASH neurons: cellular response and adaptation to chemical repellents

    E-Print Network [OSTI]

    Schafer, William R.

    Erratum In vivo imaging of C. elegans ASH neurons: cellular response and adaptation to chemical neurons highlighted. From the ASH cell body, the dendrite runs anteriorly until the tip of the head ending

  7. Soil stabilization using optimum quantity of calcium chloride with Class F fly ash

    E-Print Network [OSTI]

    Choi, Hyung Jun

    2006-10-30T23:59:59.000Z

    Ash at 90days ............... 38 5-13 Stress Strain Curve of 6% CaCl2+10% Fly Ash at 90days ............... 39 5-14 Stress Strain Curve of 4% CaCl2+15% Fly Ash at 90days ............... 39 5-15 Environmental Scanning Electron Microscopy... (E-SEM) of Class F Fly Ash ................................................................................. 40 5-16 Environmental Scanning Electron Microscopy (E-SEM) of Control Soil after 7 Days of Curing...

  8. High-performance, high-volume fly ash concrete

    SciTech Connect (OSTI)

    NONE

    2008-01-15T23:59:59.000Z

    This booklet offers the construction professional an in-depth description of the use of high-volume fly ash in concrete. Emphasis is placed on the need for increased utilization of coal-fired power plant byproducts in lieu of Portland cement materials to eliminate increased CO{sub 2} emissions during the production of cement. Also addressed is the dramatic increase in concrete performance with the use of 50+ percent fly ash volume. The booklet contains numerous color and black and white photos, charts of test results, mixtures and comparisons, and several HVFA case studies.

  9. Ash reduction system using electrically heated particulate matter filter

    DOE Patents [OSTI]

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI

    2011-08-16T23:59:59.000Z

    A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.

  10. Continuous air agglomeration method for high carbon fly ash beneficiation

    DOE Patents [OSTI]

    Gray, McMahon L. (Pittsburgh, PA); Champagne, Kenneth J. (Monongahela, PA); Finseth, Dennis H. (Pittsburgh, PA)

    2000-01-01T23:59:59.000Z

    The carbon and mineral components of fly ash are effectively separated by a continuous air agglomeration method, resulting in a substantially carboree mineral stream and a highly concentrated carbon product. The method involves mixing the fly ash comprised of carbon and inorganic mineral matter with a liquid hydrocarbon to form a slurry, contacting the slurry with an aqueous solution, dispersing the hydrocarbon slurry into small droplets within the aqueous solution by mechanical mixing and/or aeration, concentrating the inorganic mineral matter in the aqueous solution, agglomerating the carbon and hydrocarbon in the form of droplets, collecting the droplets, separating the hydrocarbon from the concentrated carbon product, and recycling the hydrocarbon.

  11. Coal-ash slag attack and corrosion of refractories

    SciTech Connect (OSTI)

    Bonar, J.A. (Carborundum Co., Niagara Falls, NY); Kennedy, C.R.; Swaroop, R.B.

    1980-04-01T23:59:59.000Z

    The corrosion characteristics of a variety of fused-cast refractories in contact with various coal-ash slags were investigated. A fused-cast chrome-spinel refractory exhibited excellent corrosion resistance to both acidic and basic coal-ash slags at 1500/sup 0/C, even in the absence of water cooling. The slag-refractory interaction was limited to the formation of a stable band of recrystallized hercynitic spinel. Alumina-chromia refractories were superior to alumina and magnesia-chrome refractories when exposed to acidic slags.

  12. Ni/YSZ Anode Interactions with Impurities in Coal Gas

    SciTech Connect (OSTI)

    Marina, Olga A.; Pederson, Larry R.; Coyle, Christopher A.; Thomsen, Edwin C.; Coffey, Greg W.

    2009-10-16T23:59:59.000Z

    Performance of solid oxide fuel cell (SOFC) with nickel/zirconia anodes on synthetic coal gas in the presence of low levels of phosphorus, arsenic, selenium, sulfur, hydrogen chloride, and antimony impurities were evaluated. The presence of phosphorus and arsenic led to the slow and irreversible SOFC degradation due to the formation of secondary phases with nickel, particularly close to the gas inlet. Phosphorus and antimony surface adsorption layers were identified as well. Hydrogen chloride and sulfur interactions with the nickel were limited to the surface adsorption only, whereas selenium exposure also led to the formation of nickel selenide for highly polarized cells.

  13. Overview of SOFC Anode Interactions with Coal Gas Impurities

    SciTech Connect (OSTI)

    Marina, Olga A.; Pederson, Larry R.; Gemmen, Randall; Gerdes, Kirk; Finklea, Harry; Celik, Ismail B.

    2010-05-01T23:59:59.000Z

    An overview of the results of SOFC anode interactions with phosphorus, arsenic, selenium, sulfur, antimony, and hydrogen chloride as single contaminants or in combinations is discussed. Tests were performed using both anode- and electrolyte-supported cells in synthetic and actual coal gas for periods greater than 1000 hours. Post-test analyses were performed to identify reaction products formed and their distribution, and compared to phases expected from thermochemical modeling. The ultimate purpose of this work is to establish maximum permissible concentrations for impurities in coal gas, to aid in the selection of appropriate coal gas clean-up technologies.

  14. Overview of SOFC Anode Interactions with Coal Gas Impurities

    SciTech Connect (OSTI)

    O. A. Marina; L. R. Pederson; R. Gemmen; K. Gerdes; H. Finklea; I. B. Celik

    2010-03-01T23:59:59.000Z

    An overview of the results of SOFC anode interactions with phosphorus, arsenic, selenium, sulfur, antimony, and hydrogen chloride as single contaminants or in combinations is discussed. Tests were performed using both anode- and electrolyte-supported cells in synthetic and actual coal gas for periods greater than 1000 hours. Post-test analyses were performed to identify reaction products formed and their distribution, and compared to phases expected from thermochemical modeling. The ultimate purpose of this work is to establish maximum permissible concentrations for impurities in coal gas, to aid in the selection of appropriate coal gas clean-up technologies.

  15. Wall conditioning experiments on TFTR using impurity pellet injection

    SciTech Connect (OSTI)

    Strachan, J.D.; Mansfield, D.K.; Bell, M.G. [and others

    1993-11-01T23:59:59.000Z

    This work describes experiments intended to optimize the limiter conditioning for TFTR supershots. It is shown that deposition of thin layers of lithium on the limiters by impurity pellet injection changes the plasma-wall interaction and improves supershot performance. Series of up to ten Ohmic plasmas each with two lithium pellets were useful in preconditioning the limiter. Generally, plasma performance increased with the amount of lithium deposited up to the maximal amount which could be deposited. Experiments were performed with different materials being deposited (carbon, boron and lithium) and with different methods of deposition.

  16. Biogas Impurities and Cleanup for Fuel Cells | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The FutureCommentsEnergyandapproximately 10 wt%in Defense, Aviation,Impurities

  17. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8, 2000Consumption SurveyEnergyphysicistEngineering Metal Impurities in

  18. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8, 2000Consumption SurveyEnergyphysicistEngineering Metal Impurities

  19. Nonequilibrium Spintronic Transport through an Artificial Kondo Impurity: Conductance, Magnetoresistance, and Shot Noise

    E-Print Network [OSTI]

    Sánchez, David

    Nonequilibrium Spintronic Transport through an Artificial Kondo Impurity: Conductance processes lift the level degeneracy, yielding "0 R, where R is a phenomenological spin flip scatter- ing

  20. Quasiparticle resonant states induced by a unitary impurity in a d-wave superconductor

    E-Print Network [OSTI]

    Zhu, JX; Lee, TK; Ting, CS; Hu, Chia-Ren.

    2000-01-01T23:59:59.000Z

    of the energy gap, such impurities can cause a strong pair-breaking effect.3 PRB 610163-1829/2000/61~13!/8667~4!/$15.00 y impurity in a d-wave superconductor Zhu , University of Houston, Houston, Texas 77204 Lee , Taipei 11529, Taiwan, Republic of China... for uncovering the physics intrinsic to an isolated impurity. As shown in Fig. 1, we find that the LDOS spectrum near the impurity is highly sensitive to the position of m within the energy band, and the PRB 61S parameter g . In Fig. 1~a!, m50 ~Ref. 23...

  1. The spin exchange interaction effect on Tc equation of anisotropic impure superconductors

    E-Print Network [OSTI]

    P. Udomsamuthirun; R. Supadanaison

    2008-04-10T23:59:59.000Z

    We study the influence of spin exchange interaction of impurity scattering on critical temperature of anisotropic impure superconductors. The model of random nonmagnetic and magnetic impurity are revised to cover the effect of spin exchange interaction . The sign of magnitude of the second-order Born scattering have been changed after consideration the spin exchange interaction effect that also effect to form of Tc equation. We can get the general Tc equation that can be described anisotropic impure superconductors well and cover all model done before.

  2. Batch methods for enriching trace impurities in hydrogen gas for their further analysis

    DOE Patents [OSTI]

    Ahmed, Shabbir; Lee, Sheldon H.D.; Kumar, Romesh; Papdias, Dionissios D.

    2014-07-15T23:59:59.000Z

    Provided herein are batch methods and devices for enriching trace quantities of impurities in gaseous mixtures, such as hydrogen fuel. The methods and devices rely on concentrating impurities using hydrogen transport membranes wherein the time period for concentrating the sample is calculated on the basis of optimized membrane characteristics, comprising its thickness and permeance, with optimization of temperature, and wherein the enrichment of trace impurities is proportional to the pressure ratio P.sub.hi/P.sub.lo and the volume ratio V.sub.1/V.sub.2, with following detection of the impurities using commonly-available detection methods.

  3. RESEARCH NEEDS IN MINERAL BY-PRODUCTS UTILIZATION: FLY ASH, SILICA FUME AND SLAG

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    of coal in electric power plants. It is captured by either mechanical separators, electrostatic. 2.0 Research Needs Concerning Fly Ash Utilization 2.1 CLSM Fly Ash Slurry Controlled low strength materials (CLSM), as classified by ACI Committee 229, have been produced using fly ash slurry [9

  4. Correlation relations between mineralogical components in ash from Kaa-Khem coals

    SciTech Connect (OSTI)

    N.N. Yanchat; L.Kh. Tas-ool [Russian Academy of Sciences, Kyzyl (Russia). Tuvinian Institute for Complex Exploration of Natural Resources

    2008-08-15T23:59:59.000Z

    Regression analysis was used to study correlation relations between the mineral components of coals. Regularities in the variability of the concentrations of individual ash-forming elements with changing ash contents of coals and changing seam depth were found. The X-ray diffraction characteristics of coal ashes and the qualitative composition of their mineralogical components are presented.

  5. INCO-WBC-1-509173 Reintegration of coal ash disposal sites and mitigation of

    E-Print Network [OSTI]

    1 INCO-WBC-1-509173 RECOAL Reintegration of coal ash disposal sites and mitigation of pollution of coal ash disposal sites Due date of deliverable: 12.2007 Actual submission date: 02.2008 Start date of the consortium (including the Commission Services) #12;2 Handbook on treatment of coal ash disposal sites Preface

  6. TRACE ELEMENTS LEACHING FROM ORGANIC SOILS STABILIZED WITH HIGH CARBON FLY ASH

    E-Print Network [OSTI]

    Aydilek, Ahmet

    and Se for organic soil-HCFA mixtures. Keywords: organic soil, fly ash, coal combustion products, CCPs INTRODUCTION Fly ash is a silt-size particulate collected by air pollution control systems at coal fly ashes (HCFAs) generally are disposed in landfills (Hodges and Keating 1999). However, many HCFAs

  7. Conversion of oil shale ash into zeolite for cadmium and lead removal from wastewater

    E-Print Network [OSTI]

    Shawabkeh, Reyad A.

    Conversion of oil shale ash into zeolite for cadmium and lead removal from wastewater Reyad; available online 29 October 2003 Abstract A by-product fly ash from oil shale processing was converted shale; Ash; Zeolite; Cadmium and lead removal 1. Introduction Oil shale exists in Jordan with large

  8. Hydration and strength development of binder based on high-calcium oil shale fly ash

    SciTech Connect (OSTI)

    Freidin, C. [Ben-Gurion Univ. of the Negev, Sede-Boqer (Israel)] [Ben-Gurion Univ. of the Negev, Sede-Boqer (Israel)

    1998-06-01T23:59:59.000Z

    The properties of high-calcium oil shale fly ash and low-calcium coal fly ash, which are produced in Israeli power stations, were investigated. High-calcium oil shale fly ash was found to contain a great amount of CaO{sub free} and SO{sub 3} in the form of lime and anhydrite. Mixtures of high-calcium oil shale fly ash and low-calcium coal fly ash, termed fly ash binder, were shown to cure and have improved strength. The influence of the composition and curing conditions on the compressive strength of fly ash binders was examined. The microstructure and the composition of fly ash binder after curing and long-term exposure in moist air, water and open air conditions were studied. It was determined that ettringite is the main variable in the strength and durability of cured systems. The positive effect of calcium silicate hydrates, CSH, which are formed by interaction of high-calcium oil shale fly ash and low-calcium coal fly ash components, on the carbonation and dehydration resistance of fly ash binder in open air is pronounced. It was concluded that high-calcium oil shale fly ash with high CaO{sub free} and SO{sub 3} content can be used as a binder for building products.

  9. Cleanup Verification Package for the 126-F-1, 184-F Powerhouse Ash Pit

    SciTech Connect (OSTI)

    S. W. Clark and H. M Sulloway

    2007-10-31T23:59:59.000Z

    This cleanup verification package documents completion of remedial action for the 126-F-1, 184-F Powerhouse Ash Pit. This waste site received coal ash from the 100-F Area coal-fired steam plant. Leakage of process effluent from the 116-F-14 , 107-F Retention Basins flowed south into the ash pit, contaminating the northern portion.

  10. Cleanup Verification Package for the 126-F-1, 184-F Powerhouse Ash Pit

    SciTech Connect (OSTI)

    S. W. Clark and H. M. Sulloway

    2007-09-26T23:59:59.000Z

    This cleanup verification package documents completion of remedial action for the 126-F-1, 184-F Powerhouse Ash Pit. This waste site received coal ash from the 100-F Area coal-fired steam plant. Leakage of process effluent from the 116-F-14 , 107-F Retention Basins flowed south into the ash pit, contaminating the northern portion.

  11. Impurity pellet injection experiments at TFTR. Final performance report

    SciTech Connect (OSTI)

    Marmar, E.S.

    1992-12-01T23:59:59.000Z

    Impurity (Li and C) pellet injection experiments on TFTR have produced a number of new and significant results. (1) We observe reproducible improvements of TFTR supershots after wall-conditioning by Li pellet injection (`lithiumization`). (2) We have made accurate measurements of the pitch angle profiles of the internal magnetic field using two novel techniques. The first measures the internal field pitch from the polarization angles of Li{sup +} line emission from the pellet ablation cloud, while the second measures the pitch angle profiles by observing the tilt of the cigar-shaped Li{sup +} emission region of the ablation cloud. (3) Extensive measurements of impurity pellet penetration into plasmas with central temperatures ranging from {approximately}0.3 to {approximately}7 keV have been made and compared with available theoretical models. Other aspects of pellet cloud physics have been investigated. (4) Using pellets as a well defined perturbation has allowed study of transport phenomena. In the case of small pellet perturbations, the characteristics of the background plasmas are probed, while with large pellets, pellet induced effects are clearly observed. These main results are discussed in more detail in this paper.

  12. Integrated Bayesian Estimation of Zeff in the TEXTOR Tokamak from Bremsstrahlung and CX Impurity Density Measurements

    SciTech Connect (OSTI)

    Verdoolaege, G.; Oost, G. van [Department of Applied Physics, Ghent University, Rozier 44, 9000 Gent (Belgium); Hellermann, M. G. von; Jaspers, R. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Ichir, M. M. [Laboratoire des Signaux et Systemes, Unite mixte de recherche 8506 (CNRS-Supelec-UPS), Supelec, Plateau de Moulon, 91192 Gif-sur-Yvette (France)

    2006-11-29T23:59:59.000Z

    The validation of diagnostic date from a nuclear fusion experiment is an important issue. The concept of an Integrated Data Analysis (IDA) allows the consistent estimation of plasma parameters from heterogeneous data sets. Here, the determination of the ion effective charge (Zeff) is considered. Several diagnostic methods exist for the determination of Zeff, but the results are in general not in agreement. In this work, the problem of Zeff estimation on the TEXTOR tokamak is approached from the perspective of IDA, in the framework of Bayesian probability theory. The ultimate goal is the estimation of a full Zeff profile that is consistent both with measured bremsstrahlung emissivities, as well as individual impurity spectral line intensities obtained from Charge Exchange Recombination Spectroscopy (CXRS). We present an overview of the various uncertainties that enter the calculation of a Zeff profile from bremsstrahlung date on the one hand, and line intensity data on the other hand. We discuss a simple linear and nonlinear Bayesian model permitting the estimation of a central value for Zeff and the electron density ne on TEXTOR from bremsstrahlung emissivity measurements in the visible, and carbon densities derived from CXRS. Both the central Zeff and ne are sampled using an MCMC algorithm. An outlook is given towards possible model improvements.

  13. CHARACTERIZATION OF PD IMPURITIES AND TWIN BOUNDARY DEFECTS IN DETECTOR GRADE CDZNTE CRYSTALS

    SciTech Connect (OSTI)

    Duff, M.

    2011-06-22T23:59:59.000Z

    Synthetic CdZnTe or ''CZT'' crystals are highly suitable for {gamma}-spectrometers operating at the room temperature. Secondary phases (SP) in CZT are known to inhibit detector performance, particularly when they are present in large numbers or dimensions. These SP may exist as voids or composites of non-cubic phase metallic Te layers with bodies of polycrystalline and amorphous CZT material and voids. Defects associated with crystal twining may also influence detector performance in CZT. Using transmission electron microscopy, we identify two types of defects that are on the nano scale. The first defect consists of 40 nm diameter metallic Pd/Te bodies on the grain boundaries of Te-rich composites. Although the nano-Pd/Te bodies around these composites may be unique to the growth source of this CZT material, noble metal impurities like these may contribute to SP formation in CZT. The second defect type consists of atom-scale grain boundary dislocations. Specifically, these involve inclined ''finite-sized'' planar defects or interfaces between layers of atoms that are associated with twins. Finite-sized twins may be responsible for the subtle but observable striations that can be seen with optical birefringence imaging and synchrotron X-ray topographic imaging.

  14. Volcanic ash: What it is and how it forms

    SciTech Connect (OSTI)

    Heiken, G.

    1991-09-13T23:59:59.000Z

    There are four basic eruption processes that produce volcanic ash: (1) decompression of rising magma, gas bubble growth, and fragmentation of the foamy magma in the volcanic vent (magmatic), (2) explosive mixing of magma with ground or surface water (hydrovolcanic), (3) fragmentation of country rock during rapid expansion of steam and/or hot water (phreatic), and (4) breakup of lava fragments during rapid transport from the vent. Variations in eruption style and the characteristics of volcanic ashes produced during explosive eruptions depend on many factors, including magmatic temperature, gas content, viscosity and crystal content of the magma before eruption, the ratio of magma to ground or surface water, and physical properties of the rock enclosing the vent. Volcanic ash is composed of rock and mineral fragments, and glass shards, which is less than 2 mm in diameter. Glass shard shapes and sizes depend upon size and shape of gas bubbles present within the magma immediately before eruption and the processes responsible for fragmentation of the magma. Shards range from slightly curved, thin glass plates, which were broken from large, thin-walled spherical bubble walls, to hollow needles broken from pumiceous melts containing gas bubbles stretched by magma flow within the volcanic vent. Pumice fragments make up the coarser-grained portions of the glass fraction. Particle sizes range from meters for large blocks expelled near the volcanic vent to nanometers for fine ash and aerosol droplets within well-dispersed eruption plumes. 18 refs., 6 figs., 1 tab.

  15. Maintaining and Improving Marketability of Coal Fly Ash

    E-Print Network [OSTI]

    is produced when coal is consumed by power plants Fly ash can be used beneficially in numerous applications-fired power plants work to create cleaner skies, they'll likely fill up landfills with millions more tons.05 0.05 #12;6 Challenge: Mercury Controls One approach to reducing mercury emissions from power plants

  16. Characterization of core impurity transport and accumulation in various operating regimes in DIII-D

    SciTech Connect (OSTI)

    Wade, M.R. [Oak Ridge National Lab., TN (United States); Whyte, D.G. [INRS--Energie et Materiaux, Varennes, Quebec (Canada); Wood, R.D. [Lawrence Livermore National Lab., CA (United States); West, W.P. [General Atomics, San Diego, CA (United States)

    1996-07-01T23:59:59.000Z

    Impurity contaminants in the core plasma of future burning devices such as the International Thermonuclear Experimental Reactor (ITER) are inevitable and will undoubtedly have a deleterious effect on plasma performance. Unfortunately, because of the limited amount of information available, the models presently being used to predict ITER performance simply assume a flat concentration profile for all impurities with an ad hoc concentration chosen for each impurity. In an attempt to start closing the gap between present experimental data and these models, experiments have been conducted on DIII-D with particular emphasis placed on (1) characterizing the buildup of intrinsic impurities in the plasma core in various confinement and divertor regimes; (2) measuring the steady-state impurity density profiles in various operating regimes; and (3) determining whether impurity transport properties are dependent on the charge of the impurity. The primary focus of these studies has been on characterizing impurity buildup in a wide variety of operating conditions in ELMing H-mode plasmas. However, enhanced confinement regimes such as ELM-free H-mode, VH-mode, and the negative central shear (NCS) regime offer the potential of a more attractive reactor scenario. Since the degree of impurity accumulation will have a significant impact on the attractiveness of these regimes, studies have also been conducted to characterize impurity buildup in these regimes. In the present configuration of DIII-D in which graphite tiles cover {approximately} 90% of the plasma facing surface, spectroscopic surveys show carbon to be the dominant impurity with the core carbon concentration typically between 1--3% of the electron density.

  17. Soil stabilization and pavement recycling with self-cementing coal fly ash

    SciTech Connect (OSTI)

    NONE

    2008-01-15T23:59:59.000Z

    This manual provides design information for self-cementing coal fly ash as the sole stabilizing agent for a wide range of engineering applications. As in any process, the application of sound engineering practices, appropriate testing, and evaluation of fly ash quality and characteristics will lend themselves to successful projects using the guidelines in this manual. Topics discussed include: self-cementing coal fly ash characteristics; laboratory mix design; stabilization of clay soils; stabilisation of granular materials; construction considerations; high sulfate ash; environmental considerations for fly ash stabilization; design considerations; state specification/guidelines/standards; and a sample of a typical stabilization specification.

  18. Use of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung*

    E-Print Network [OSTI]

    Chung, Deborah D.L.

    in the United States generate 80 million tons of fly ash as a by-product each year, primarily from coal combustion [1]. Fly ash is typically disposed in landfills, but it is preferred to convert fly ashUse of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung

  19. Method for increasing the rate of compressive strength gain in hardenable mixtures containing fly ash

    DOE Patents [OSTI]

    Liskowitz, John W. (Belle Mead, NJ); Wecharatana, Methi (Parsippany, NJ); Jaturapitakkul, Chai (Bangkok, TH); Cerkanowicz, deceased, Anthony E. (late of Livingston, NJ)

    1997-01-01T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention provides a method for increasing the rate of strength gain of a hardenable mixture containing fly ash by exposing the fly ash to an aqueous slurry of calcium oxide (lime) prior to its incorporation into the hardenable mixture. The invention further relates to such hardenable mixtures, e.g., concrete and mortar, that contain fly ash pre-reacted with calcium oxide. In particular, the fly ash is added to a slurry of calcium oxide in water, prior to incorporating the fly ash in a hardenable mixture. The hardenable mixture may be concrete or mortar. In a specific embodiment, mortar containing fly ash treated by exposure to an aqueous lime slurry are prepared and tested for compressive strength at early time points.

  20. Method for increasing the rate of compressive strength gain in hardenable mixtures containing fly ash

    DOE Patents [OSTI]

    Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

    1997-10-28T23:59:59.000Z

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention provides a method for increasing the rate of strength gain of a hardenable mixture containing fly ash by exposing the fly ash to an aqueous slurry of calcium oxide (lime) prior to its incorporation into the hardenable mixture. The invention further relates to such hardenable mixtures, e.g., concrete and mortar, that contain fly ash pre-reacted with calcium oxide. In particular, the fly ash is added to a slurry of calcium oxide in water, prior to incorporating the fly ash in a hardenable mixture. The hardenable mixture may be concrete or mortar. In a specific embodiment, mortar containing fly ash treated by exposure to an aqueous lime slurry are prepared and tested for compressive strength at early time points. 2 figs.

  1. Regeneratively cooled coal combustor/gasifier with integral dry ash removal

    DOE Patents [OSTI]

    Beaufrere, A.H.

    1982-04-30T23:59:59.000Z

    A coal combustor/gasifier is disclosed which produces a low or medium combustion gas fired furnances or boilers. Two concentric shells define a combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

  2. Effects of bulk charged impurities on the bulk and surface transport in three-dimensional topological insulators

    SciTech Connect (OSTI)

    Skinner, B.; Chen, T.; Shklovskii, B. I., E-mail: shklovsk@physics.spa.umn.edu [University of Minnesota, Fine Theoretical Physics Institute (United States)

    2013-09-15T23:59:59.000Z

    In the three-dimensional topological insulator (TI), the physics of doped semiconductors exists literally side-by-side with the physics of ultrarelativistic Dirac fermions. This unusual pairing creates a novel playground for studying the interplay between disorder and electronic transport. In this mini-review, we focus on the disorder caused by the three-dimensionally distributed charged impurities that are ubiquitous in TIs, and we outline the effects it has on both the bulk and surface transport in TIs. We present self-consistent theories for Coulomb screening both in the bulk and at the surface, discuss the magnitude of the disorder potential in each case, and present results for the conductivity. In the bulk, where the band gap leads to thermally activated transport, we show how disorder leads to a smaller-than-expected activation energy that gives way to variable-range hopping at low temperatures. We confirm this enhanced conductivity with numerical simulations that also allow us to explore different degrees of impurity compensation. For the surface, where the TI has gapless Dirac modes, we present a theory of disorder and screening of deep impurities, and we calculate the corresponding zero-temperature conductivity. We also comment on the growth of the disorder potential in passing from the surface of the TI into the bulk. Finally, we discuss how the presence of a gap at the Dirac point, introduced by some source of time-reversal symmetry breaking, affects the disorder potential at the surface and the mid-gap density of states.

  3. Progress in year 2000 1. Superfluid suppression of impurity scattering in a Bose-Einstein

    E-Print Network [OSTI]

    was dramatically reduced when the velocity of the impurities was reduced below the speed of sound of the condensate of dissipation was found at a critical velocity of about 10 % of the speed of sound which corrects the higher or rotons in the case of liquid helium-4. We could create impurity atoms in a trapped BEC by transferring

  4. Radiation processes of impurities in detached divertor plasmas of JT-60U

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    , CX? Spatial distribution? Pumping Divertor: T!0.2*- 100eV n!(0.1- 50*)x1019m-3 Divertor plates: Heat of divertor · Control of fuel particles · Control of impurities · Mitigation of heat load onto target plates load => Erosion, impurities Heat particles R ecycling Im purities *Recombining plasma Core: T!10 keV n

  5. Effects of nonmagnetic impurities on the spin transport property of a graphene nanoribbon device

    E-Print Network [OSTI]

    Lee, EokKyun

    Effects of nonmagnetic impurities on the spin transport property of a graphene nanoribbon device to an edge of a graphene nanoribbon device GND with zigzag edges. A center-located impurity enables both American Institute of Physics. DOI: 10.1063/1.3138776 I. INTRODUCTION Electronic spin transport in graphene

  6. Role of trace impurities in large-volume noble gas atmospheric-pressure glow discharges

    E-Print Network [OSTI]

    Raja, Laxminarayan L.

    Role of trace impurities in large-volume noble gas atmospheric-pressure glow discharges Xiaohui. Large-volume APG discharges find numerous applications in processing of material surfaces,1 ozone-purity helium is presented, and the role of trace impurities in such noble gas plasmas is established. Trace

  7. STUDY OF RADIOACTIVE IMPURITIES IN SOLIDS. II. EFFECTS OF RELAXATION AND RADIOFREQUENCY

    E-Print Network [OSTI]

    Boyer, Edmond

    565 STUDY OF RADIOACTIVE IMPURITIES IN SOLIDS. II. EFFECTS OF RELAXATION AND RADIOFREQUENCY D magnétique et l'orientation nucléaire). Abstract. 2014 The nuclear radiation characteristics of a radioactive impurity embedded in a solid matrix, depend on the properties of the levels involved in the radiative

  8. Volatile impurities in the ceramic form for the Plutonium Immobilization Project (PIP)

    SciTech Connect (OSTI)

    Cozzi, A.D.

    2000-03-02T23:59:59.000Z

    The primary goal for the impurity tests performed at SRS was to determine the maximum level of volatile impurities that can be accommodated into the ceramic form without significantly affecting product properties. The properties investigated in this study are the apparent porosity and the phase assemblage.

  9. Impurity feedback control for enhanced divertor and edge radiation in DIII-D discharges

    SciTech Connect (OSTI)

    Jackson, G.L.; Staebler, G.M.; Allen, S.L. [and others

    1996-10-01T23:59:59.000Z

    Long pulse and steady state fusion ignition devices will require a significant radiated power fraction to minimize heat flux to, and sputtering of, the first wall. While impurity gases have been proposed to enhance radiation, precise control of impurity gas injection is essential to achieve an adequate radiative power fraction while maintaining good energy confinement and low central impurity concentration. We report here the first experiments in the DIII-D tokamak using feedback control of the rate of impurity gas injection. These experiments were carried out with active divertor pumping using the in-situ DIII-D cryopump. The radiated power fraction was controlled by sensing either UN edge line radiation (Ne{sup +7}) or mantle radiation from selected bolometer channels and using the DIII-D digital plasma control system to calculate radiated power real-time and generate an error signal to control an impurity gas injector valve.

  10. Coulomb impurity scattering in topological insulator thin films

    SciTech Connect (OSTI)

    Yin, Gen; Wickramaratne, Darshana; Lake, Roger K., E-mail: rlake@ee.ucr.edu [Department of Electrical Engineering, University of California, Riverside, California 92521 (United States); Zhao, Yuanyuan [Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204 (United States)

    2014-07-21T23:59:59.000Z

    Inter-surface coupling in thin-film topological insulators can reduce the surface state mobility by an order of magnitude in low-temperature transport measurements. The reduction is caused by a reduction in the group velocity and an increased s{sub z} component of the surface-state spin which weakens the selection rule against large-angle scattering. An intersurface potential splits the degenerate bands into a Rashba-like bandstructure. This reduces the intersurface coupling, it largely restores the selection rule against large angle scattering, and the ring-shaped valence band further reduces backscattering by requiring, on average, larger momentum transfer for backscattering events. The effects of temperature, Fermi level, and intersurface potential on the Coulomb impurity scattering limited mobility are analyzed and discussed.

  11. Distribution of Carbon Impurity Sources Between Low and High Field Side Measured via Zeeman-Spectroscopy in JET

    E-Print Network [OSTI]

    Distribution of Carbon Impurity Sources Between Low and High Field Side Measured via Zeeman-Spectroscopy in JET

  12. Standard practice for removal of uranium or plutonium, or both, for impurity assay in uranium or plutonium materials

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2006-01-01T23:59:59.000Z

    Standard practice for removal of uranium or plutonium, or both, for impurity assay in uranium or plutonium materials

  13. Theoretical Description of Heavy Impurity Transport and its Application to the Modelling of Tungsten in JET and ASDEX Upgrade

    E-Print Network [OSTI]

    Theoretical Description of Heavy Impurity Transport and its Application to the Modelling of Tungsten in JET and ASDEX Upgrade

  14. Soft X-Ray Tomographic Reconstruction of JET ILW Plasmas with Tungsten Impurity and Different Spectral Response of Detectors

    E-Print Network [OSTI]

    Soft X-Ray Tomographic Reconstruction of JET ILW Plasmas with Tungsten Impurity and Different Spectral Response of Detectors

  15. JV Task 6 - Coal Ash Resources Research Consortium Research

    SciTech Connect (OSTI)

    Debra Pflughoeft-Hassett; Tera Buckley; Bruce Dockter; Kurt Eylands; David Hassett; Loreal Heebink; Erick Zacher

    2008-04-01T23:59:59.000Z

    The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of coal combustion by-products (CCBs). CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program (JSRP), which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCB performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 1998 to 2007 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. CARRC topical reports were prepared on several completed tasks. Specific CARRC 1998B2007 accomplishments included: (1) Development of several ASTM International Standard Guides for CCB utilization applications. (2) Organization and presentation of training courses for CCB professionals and teachers. (3) Development of online resources including the Coal Ash Resource Center, Ash from Biomass in Coal (ABC) of cocombustion ash characteristics, and the Buyer's Guide to Coal-Ash Containing Products. In addition, development of expanded information on the environmental performance of CCBs in utilization settings included the following: (1) Development of information on physical properties and engineering performance for concrete, soil-ash blends, and other products. (2) Training of students through participation in CARRC research projects. (3) Participation in a variety of local, national, and international technical meetings, symposia, and conferences by presenting and publishing CCB-related papers.

  16. EFFECTS OF FLY ASH ON MERCURY OXIDATION DURING POST COMBUSTION CONDITIONS

    SciTech Connect (OSTI)

    Glenn A. Norton; Hongqun Yang; Robert C. Brown; Dennis L. Laudal; Grant E. Dunham; John Erjavec; Joseph M. Okoh

    2002-01-31T23:59:59.000Z

    Tests were performed in simulated flue gas streams using fly ash from the electrostatic precipitators of two full-scale utility boilers. One fly ash was from a Powder River Basin (PRB) coal, while the other was from Blacksville coal. Elemental Hg was injected upstream from samples of fly ash loaded onto filters housed in an oven at 120 or 180 C. Concentrations of oxidized and elemental Hg downstream from the filters were determined using the Ontario Hydro method. The gas stream composition and whether or not ash was present in the gas stream were the two most important variables affecting Hg oxidation. The presence of HCl, NO, NO{sub 2}, and SO{sub 2} were all important with respect to Hg oxidation, with NO{sub 2} and HCl being the most important. The presence of NO suppressed Hg oxidation in these tests. Although the two fly ashes were chemically and mineralogically diverse, there were generally no large differences in catalytic potential (for oxidizing Hg) between them. Similarly, no ash fraction appeared to be highly catalytic relative to other ash fractions. This includes fractions enriched in unburned carbon and fractions enriched in iron oxides. Although some differences of lesser magnitude were observed in the amount of oxidized Hg formed, levels of oxidized Hg generally tracked well with the surface areas of the different ashes and ash fractions. Therefore, although the Blacksville fly ash tended to show slightly more catalytic activity than the PRB fly ash, this could be due to the relatively high surface area of that ash. Similarly, for Blacksville fly ash, using nonmagnetic ash resulted in more Hg oxidation than using magnetic ash, but this again tracked well with the relative surface areas of the two ash fractions. Test results suggest that the gas matrix may be more important in Hg oxidation chemistry than the fly ash composition. Combustion tests were performed in which Blacksville and PRB fly ashes were injected into filtered (via a baghouse with Teflon bags) flue gas obtained while firing PRB coal in a 35 kW combustor. The Ontario Hydro method was used to determine the Hg speciation after fly ash injection. Wall effects in the combustor complicated interpretation of testing data, although a number of observations could still be made. The amount of Hg collected in the Ontario Hydro impingers was lower than anticipated, and is probably due to sorption of Hg by the fly ash. While firing PRB coal without any ash injection, the percent oxidized Hg in the gas stream was fairly high (average of 63%). The high levels of vapor phase oxidized Hg in these base line tests may be due to catalytic effects from the refractory materials in the combustor. When PRB fly ash was injected into a filtered PRB flue gas stream, the percentage of oxidized Hg in the gas stream decreased dramatically. Decreases in the percentage of oxidized Hg were also observed while injecting Blacksville fly ash, but to a lesser extent. Injecting whole Blacksville fly ash into the filtered PRB flue gas appeared to result in greater concentrations of oxidized Hg relative to the tests where whole PRB fly ash was injected. However, because the Blacksville fly ash has a relatively high surface area, this may be only a surface area effect.

  17. EFFECTS OF FLY ASH ON MERCURY OXIDATION DURING POST COMBUSTION CONDITIONS

    SciTech Connect (OSTI)

    Unknown

    2000-10-01T23:59:59.000Z

    Tests were performed in simulated flue gas streams using two fly ash samples from the electrostatic precipitators of two full-scale utility boilers. One fly ash was derived from a Powder River Basin (PRB) coal, while the other was derived from Blacksville coal (Pittsburgh No. 8 seam). The tests were performed at temperatures of 120 and 180 C under different gas compositions using whole fly ash samples as well as magnetic and nonmagnetic concentrates from sized fly ash. Only the Blacksville ash contained magnetic phases. The whole and fractionated fly ash samples were analyzed for morphology, chemical composition, mineralogical composition, total organic carbon, porosity, and surface area. Mineralogically, the Blacksville ash was composed predominantly of magnetite, hematite, quartz, and mullite, while the PRB ash contained mostly quartz with lesser amounts of lime, periclase, and calcium aluminum oxide. The iron oxides in the Blacksville ash were concentrated almost entirely in the largest size fraction. As anticipated, there was not a clean separation of magnetic (Fe-rich) and nonmagnetic (aluminosilicate-rich) phases for the Blacksville ash. The Blacksville ash had a significantly higher surface area and a much higher unburned carbon content than the PRB ash. Elemental mercury (Hg) streams were injected into the simulated flue gas and passed over filters (housed in a convection oven) loaded with fly ash. Concentrations of total, oxidized, and elemental Hg downstream from the ash samples were determined by the Ontario Hydro Method. The gas stream composition and whether or not ash was present in the gas stream were the two most important variables. Based on the statistical analyses, the presence of HCl, NO, NO{sub 2}, and SO{sub 2} and all two-way gas interactions were significant. In addition, it appears that even four-factor interactions between those gases are significant. The HCl, NO{sub 2}, and SO{sub 2} were critical gases resulting in Hg oxidation, while the presence of NO appeared to suppress oxidation. The Blacksville fly ash tended to show slightly more catalytic activity than the PRB fly ash, but this could be largely due to the higher surface area of the Blacksville ash. Temperature was not a statistically important factor. The magnetic (Fe-rich) phases did not appear to be more catalytically active than the nonmagnetic phases, and unburned carbon did not appear to play a critical role in oxidation chemistry.

  18. The preservation potential of ash layers in the deep-sea: the example of the 1991-Pinatubo ash in the South China Sea

    E-Print Network [OSTI]

    Wetzel, Andreas

    - burrowing animals re-opened their connection to the sea floor to obtain water for respiration and/or food deposited organic fluff with the underlying ash. Consequently, ash deposits thinner than 1 mm have not often of background sedimentation, the availability of benthic food on and within the sediment and pore water oxygen

  19. Construction of an embankment with a fly and bottom ash mixture: field performance study

    SciTech Connect (OSTI)

    Yoon, S.; Balunaini, U.; Yildirim, I.Z.; Prezzi, M.; Siddiki, N.Z. [Louisiana Transportation Research Center, Baton Rouge, LA (United States)

    2009-06-15T23:59:59.000Z

    Fly ash and bottom ash are coal combustion by-products (CCBPs) that are generated in large quantities throughout the world. It is often economical to dispose ash as mixtures rather than separately; that notwithstanding, only a few studies have been performed to investigate the behavior of fly and bottom ash mixtures, particularly those with high contents of fly ash. Also, there is very limited data available in the literature on the field performance of structures constructed using ash mixtures. This paper describes the construction and the instrumentation of a demonstration embankment built with an ash mixture (60:40 by weight of fly ash:bottom ash) on State Road 641, Terre Haute, Ind. Monitoring of the demonstration embankment was conducted for a period of 1 year from the start of construction of the embankment. The settlement of the embankment stabilized approximately 5 months after the end of its construction. According to horizontal inclinometer readings, the differential settlement at the top of the embankment is about 5 mm. Results from field quality control tests performed during construction of the demonstration embankment and monitoring data from vertical and horizontal inclinometers and settlement plates indicate that the ash mixture investigated can be considered an acceptable embankment construction material.

  20. Utilization of ash from municipal solid waste combustion. Final report, Phase I

    SciTech Connect (OSTI)

    Jones, C.M.; Hartman, R.M.; Kort, D.; Rapues, N.

    1994-09-01T23:59:59.000Z

    This ash study investigates several aspects of Municipal Waste Combustion (MWC) ash utilization to develop an alternative to the present disposal practice of landfilling in a lined monofill. Ash was investigated as a daily or final cover for municipal waste in the landfill to prevent erosion and as a road construction aggregate. Samples of eight mixtures of ash and other materials, and one sample of soil were analyzed for chemical constituents. Biological tests on these mixters were conducted, along with erosion tests and sieve analyses. A chemical analysis of each sieve size was conducted. Geotechnical properties of the most promising materials were made. Findings to this point include: all ash samples take have passed the EPA TCLP testing; chemical analysis of bottom and combined ash samples indicate less than expected variability; selected ash mixtures exhibited very low coefficients of hydraulic conductivity; all but one of the ash mixtures exhibited greater erosion resistance than the currently used landfill cover material; MWC combined analysis indicates this is a viable alternative for landfill cover; MWC ash size reactions and chemical analysis show bottom and combined ash to be a viable alternative for road construction.

  1. Differences in gasification behaviors and related properties between entrained gasifier fly ash and coal char

    SciTech Connect (OSTI)

    Jing Gu; Shiyong Wu; Youqing Wu; Ye Li; Jinsheng Gao [East China University of Science and Technology, Shanghai (China). Department of Chemical Engineering for Energy Resources and Key Laboratory of Coal Gasification of Ministry of Education

    2008-11-15T23:59:59.000Z

    In the study, two fly ash samples from Texaco gasifiers were compared to coal char and the physical and chemical properties and reactivity of samples were investigated by scanning electron microscopy (SEM), SEM-energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), N{sub 2} and CO{sub 2} adsorption method, and isothermal thermogravimetric analysis. The main results were obtained. The carbon content of gasified fly ashes exhibited 31-37%, which was less than the carbon content of 58-59% in the feed coal. The fly ashes exhibited higher Brunauer-Emmett-Teller (BET) surface area, richer meso- and micropores, more disordered carbon crystalline structure, and better CO{sub 2} gasification reactivity than coal char. Ashes in fly ashes occurred to agglomerate into larger spherical grains, while those in coal char do not agglomerate. The minerals in fly ashes, especial alkali and alkaline-earth metals, had a catalytic effect on gasification reactivity of fly ash carbon. In the low-temperature range, the gasification process of fly ashes is mainly in chemical control, while in the high-temperature range, it is mainly in gas diffusion control, which was similar to coal char. In addition, the carbon in fly ashes was partially gasified and activated by water vapor and exhibited higher BET surface area and better gasification activity. Consequently, the fact that these carbons in fly ashes from entrained flow gasifiers are reclaimed and reused will be considered to be feasible. 15 refs., 7 figs., 5 tabs.

  2. Coal-ash spills highlight ongoing risk to ecosystems

    SciTech Connect (OSTI)

    Chatterjee, R.

    2009-05-01T23:59:59.000Z

    Two recent large-scale spills of coal combustion waste have highlighted the old problem of handling the enormous quantity of solid waste produced by coal. Both spills happened at power plants run by the Tennessee Valley Authority (TVA). In December 2008 a holding pond for coal ash collapsed at a power plant in Kingstom, Tenn., releasing coal-ash sludge onto farmland and into rivers: in January 2009 a break in a pipe removing water from a holding pond for gypsum caused a spill at Widows Creek Fossil Plant in Stevenson, Ala. The article discusses the toxic outcome of such disasters on ecosystems, quoting work by Willaim Hopkins at Virginia Polytechnic Institute and State University and recommendations and reports of the US EPA. 2 photos.

  3. Ash reduction in clean coal spiral product circuits

    SciTech Connect (OSTI)

    Brodzik, P.

    2007-04-15T23:59:59.000Z

    The article describes the Derrick Corporation's Stack Sizer{trademark} technology for high capacity fine wet cleaning with long-lasting high open-area urethane screen panels. After field trials, a Stack Sizer fitted with a 100-micron urethane panel is currently processing approximately 40 stph of clean coal spiral product having about 20% ash at McCoy-Elkhorn's Bevin Branch coal preparation plant in Kentucky, USA. Product yield is about 32.5 short tons per hour with 10% ash. The material is then fed to screen bowl centrifuges for further processing. At Blue Diamond Coal's Leatherwood preparation plant similar Stacker Sizers are achieving the same results. 2 figs., 3 tabs., 2 photo.

  4. Effects of Sediment Containing Coal Ash from the Kingston Ash Release on Embryo-Larval Development in the Fathead Minnow, Pimephales promelas (Rafinesque, 1820)

    SciTech Connect (OSTI)

    Greeley Jr, Mark Stephen [ORNL] [ORNL; Elmore, Logan R [ORNL] [ORNL; McCracken, Kitty [ORNL] [ORNL; Sherrard, Rick [Tennessee Valley Authority (TVA)] [Tennessee Valley Authority (TVA)

    2014-01-01T23:59:59.000Z

    The largest environmental release of coal ash in U.S. history occurred in December 2008 with the failure of a retention structure at the Tennessee Valley Authority (TVA) Kingston Fossil Plant in East Tennessee. A byproduct of coal-burning power plants, coal ash is enriched in metals and metalloids such as selenium and arsenic with known toxicity to fish including embryonic and larval stages. The effects of contact exposure to sediments containing up to 78 % coal ash from the Kingston spill on the early development of fish embryos and larvae were examined in 7-day laboratory tests with the fathead minnow (Pimephales promelas). No significant effects were observed on hatching success, incidences of gross developmental abnormalities, or embryo-larval survival. Results suggest that direct exposures to sediment containing residual coal ash from the Kingston ash release may not present significant risks to fish eggs and larvae in waterways affected by the spill.

  5. EFFECT OF IMPURITIES ON THE PERFORMANCE OF A Pd-Ag DIFFUSER

    SciTech Connect (OSTI)

    Morgan, G.

    2010-12-16T23:59:59.000Z

    A commercially fabricated diffuser purchased from Johnson-Matthey, Inc. was evaluated for performance characterization testing at the Savannah River National Laboratory (SRNL). Different impurities are often present in the feed streams of the process diffusers, but the effect of these impurities on the diffuser performance is currently unknown. Various impurities were introduced into the feed stream of the diffuser at various levels ranging from 0.5% to 10% of the total flow in order to determine the effect that these impurities have on the permeation of hydrogen through the palladium-silver membrane. The introduction of various impurities into the feed stream of the diffuser had a minimal effect on the overall permeation of hydrogen through the Pd-Ag membrane. Of the four impurities introduced into the feed stream, carbon monoxide (CO) was the only impurity that showed any evidence of causing a reduction in the amount of hydrogen permeating through the Pd-Ag membrane. The hydrogen permeation returned to its baseline level after the CO was removed from the feed stream. There were no lasting effects of the CO exposure on the ability of the membrane to effectively separate hydrogen from the non-hydrogen species in the gas stream under the conditions tested.

  6. Classical confinement and outward convection of impurity ions in the MST RFP

    SciTech Connect (OSTI)

    Kumar, S. T. A.; Den Hartog, D. J.; Mirnov, V. V.; Eilerman, S.; Nornberg, M.; Reusch, J. A.; Sarff, J. S. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Caspary, K. J.; Chapman, B. E.; Parke, E. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Magee, R. M. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Brower, D. L.; Ding, W. X.; Lin, L. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States); Craig, D. [Physics Department, Wheaton College, Wheaton, Illinois 60187 (United States); Fiksel, G. [Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Laboratory for Laser Energetics, University of Rochester, Rochester, New York (United States)

    2012-05-15T23:59:59.000Z

    Impurity ion dynamics measured with simultaneously high spatial and temporal resolution reveal classical ion transport in the reversed-field pinch. The boron, carbon, oxygen, and aluminum impurity ion density profiles are obtained in the Madison Symmetric Torus [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] using a fast, active charge-exchange-recombination-spectroscopy diagnostic. Measurements are made during improved-confinement plasmas obtained using inductive control of tearing instability to mitigate stochastic transport. At the onset of the transition to improved confinement, the impurity ion density profile becomes hollow, with a slow decay in the core region concurrent with an increase in the outer region, implying an outward convection of impurities. Impurity transport from Coulomb collisions in the reversed-field pinch is classical for all collisionality regimes, and analysis shows that the observed hollow profile and outward convection can be explained by the classical temperature screening mechanism. The profile agrees well with classical expectations. Experiments performed with impurity pellet injection provide further evidence for classical impurity ion confinement.

  7. Oil shale ash-layer thickness and char combustion kinetics

    SciTech Connect (OSTI)

    Aldis, D.F.; Singleton, M.F.; Watkins, B.E.; Thorsness, C.B.; Cena, R.J.

    1992-04-15T23:59:59.000Z

    A Hot-Recycled-Solids (HRS) oil shale retort is being studied at Lawrence Livermore National Laboratory. In the HRS process, raw shale is heated by mixing it with burnt retorted shale. Retorted shale is oil shale which has been heated in an oxygen deficient atmosphere to pyrolyze organic carbon, as kerogen into oil, gas, and a nonvolatile carbon rich residue, char. In the HRS retort process, the char in the spent shale is subsequently exposed to an oxygen environment. Some of the char, starting on the outer surface of the shale particle, is burned, liberating heat. In the HRS retort, the endothermic pyrolysis step is supported by heat from the exothermic char combustion step. The rate of char combustion is controlled by three resistances; the resistance of oxygen mass transfer through the gas film surrounding the solid particle, resistance to mass transfer through a ash layer which forms on the outside of the solid particles as the char is oxidized and the resistance due to the intrinsic chemical reaction rate of char and oxygen. In order to estimate the rate of combustion of the char in a typical oil shale particle, each of these resistances must be accurately estimated. We begin by modeling the influence of ash layer thickness on the over all combustion rate of oil shale char. We then present our experimental measurements of the ash layer thickness of oil shale which has been processed in the HRS retort.

  8. Modeling the formation and size distribution of fly ash

    SciTech Connect (OSTI)

    Dahlin, R.S.

    1985-01-01T23:59:59.000Z

    A set of mathematical models has been developed to predict the size distribution of fly ash particles formed in pulverized coal combustion. The large particle mode of the size distribution, typically centered about 10 to 20 ..mu..m, is predicted by a simple breakup model that is based on the complete coalescence of molten mineral inclusions within fragments of the devolatilized coal char. The ultrafine particle mode, that is typically centered about 0.1 to 0.2 ..mu..m, is modeled in terms of ash volatilization, nucleation, and coagulation. Silica and alumina are reduced to volatile suboxides through reactions at the char surface. The volatile suboxides are transported from the char surface where they are oxidized back to the stable oxides in the bulk gas, and then nucleated in accordance with homogeneous nucleation theory. The ultrafine nuclei coagulate in accordance with Brownian coagulation theory. The predicted particle size spectra have been compared to measured size distributions from a pilot-scale combustor and a full-scale utility boiler. Considering the disproportionate loss of coarse particles in the pilot-scale unit, the agreement between the predicted and measured size distributions was considered reasonably good. Both the predicted ultrafine and large particle modes agreed reasonably well with the measured particle size distribution for the full scale boiler. The validated computer models were used to study the effect of changes in the coal ash content, coal particle size, and the combustion flame temperature.

  9. Impurities in extruded cables: A proton-induced x-ray emission diagnostic study

    SciTech Connect (OSTI)

    Crine, J.P.; Hinrichsen, P.F.; Houdayer, A. (Institut de Recherche d'Hydro-Quebec, Varennes, PQ (Canada))

    1990-06-01T23:59:59.000Z

    The impurity contents and distributions in electrical trees grown in various field-aged XLPE distribution cables were measured by micro-Proton Induced X-ray Emission (PIXE). The objectives pursued in this preliminary study were the following. Determination of any possible correlation between electrical tree initiation and the nature of some specific impurities. Evaluation of micro-PIXE as a reliable analytical technique to measure impurities in localized defects, such as small trees. For that purpose we used the micro-PIXE facility of the Laboratoire de Physique Nucleaire at University of Montreal where proton beams of {approx}20 microns can be focused on small samples. From the emitted x-rays, it is possible to determine the nature and content of most impurities (whose content is above {approx}1 ppM). Cable samples with electrical trees grown either from insulation shield or from water trees were analyzed. A few field-aged cable samples containing breakdown channels of various sizes were also analyzed. The aim here was to determine whether impurities could still be detected after breakdown. The observations made can be summarized as follows: the electrical trees studied were heavily contaminated by a wide variety of impurities; electrical trees contain the same impurities as the connecting water trees and the amounts are about the same in both types of trees; provided that the energy released during breakdown is not too high, that is as long as breakdown channels remain small; the minimum level of contamination leading to tree growth is difficult to ascertain; no clear correlation can be established between the nature of impurities and electrical tree initiation; it cannot be determined whether contamination leads to tree initiation or whether contamination follows tree growth; and micro-PIXE is well suited to study impurities in electrical (and water) trees. 20 refs., 18 figs., 8 tabs.

  10. Thermal Analysis of Surrogate Simulated Molten Salts with Metal Chloride Impurities for Electrorefining Used Nuclear Fuel

    SciTech Connect (OSTI)

    Toni Y. Gutknecht; Guy L. Fredrickson; Vivek Utgikar

    2012-04-01T23:59:59.000Z

    This project is a fundamental study to measure thermal properties (liquidus, solidus, phase transformation, and enthalpy) of molten salt systems of interest to electrorefining operations, which are used in both the fuel cycle research & development mission and the spent fuel treatment mission of the Department of Energy. During electrorefining operations the electrolyte accumulates elements more active than uranium (transuranics, fission products and bond sodium). The accumulation needs to be closely monitored because the thermal properties of the electrolyte will change as the concentration of the impurities increases. During electrorefining (processing techniques used at the Idaho National Laboratory to separate uranium from spent nuclear fuel) it is important for the electrolyte to remain in a homogeneous liquid phase for operational safeguard and criticality reasons. The phase stability of molten salts in an electrorefiner may be adversely affected by the buildup of fission products in the electrolyte. Potential situations that need to be avoided are: (i) build up of fissile elements in the salt approaching the criticality limits specified for the vessel (ii) freezing of the salts due to change in the liquidus temperature and (iii) phase separation (non-homogenous solution) of elements. The stability (and homogeneity) of the phases can potentially be monitored through the thermal characterization of the salts, which can be a function of impurity concentration. This work describes the experimental results of typical salts compositions, consisting of chlorides of strontium, samarium, praseodymium, lanthanum, barium, cerium, cesium, neodymium, sodium and gadolinium (as a surrogate for both uranium and plutonium), used in the processing of used nuclear fuels. Differential scanning calorimetry was used to analyze numerous salt samples providing results on the thermal properties. The property of most interest to pyroprocessing is the liquidus temperature. It was previously known the liquidus temperature of the molten salt would change as spent fuel is processed through the Mk-IV electrorefiner. However, the extent of the increase in liquidus temperature was not known. This work is first of its kind in determining thermodynamic properties of a molten salt electrolyte containing transuranics, fission products and bond sodium. Experimental data concluded that the melting temperature of the electrolyte will become greater than the operating temperature of the Mk-IV ER during current fuel processing campaigns. Collected data also helps predict when the molten salt electrolyte will no longer be able to support electrorefining operations.

  11. Dynamic regime of conduction in a 1D system with a single impurity

    SciTech Connect (OSTI)

    Shapiro, D. S., E-mail: shapiro@ire.cplire.ru; Artemenko, S. N., E-mail: art@ire.cplire.ru; Remizov, S. V. [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Russian Federation)

    2010-08-15T23:59:59.000Z

    A new regime of electron transport through an impurity in 1D conductors, which resembles the Josephson effect in its manifestations, is predicted. Passage of current through the impurity under voltages above the threshold value is accompanied with generation of ac current oscillations. The temperature below which the effect can be observed, the threshold voltage, and the frequency range are determined by the impurity potential and the strength of electron-electron interaction. The generation line width and the current-voltage characteristics are determined.

  12. Respirable aerosols from fluidized bed coal combustion. 3. Elemental composition of fly ash

    SciTech Connect (OSTI)

    Weissman, S.H.; Carpenter, R.L.; Newton, G.J.

    1983-02-01T23:59:59.000Z

    Fluidized bed coal combustion is a promising technology for using coal in an environmentally acceptable manner. Trace elemental constituents in fly ash from an experimental atmospheric pressure fluidized bed combustor (AFBC) are reported and compared with pulverized-coal combustor (PCC) ash data and those from other fluidized bed combustors. Bulk and size-separated particles were collected and analyzed by using spark source mass spectrometry.Fluidized bed combustor ash was similar to PCC ash in minor and trace element composition. However, AFBC ash showed less size dependence of elemental composition than has been reported for PCC ash. Bulk particle elemental composition varied with sampling position within the effluent stream. Penetration of elements through each cleanup stage and elemental enrichment were a function of the cleanup stage and the element under consideration.

  13. Integrated production/use of ultra low-ash coal, premium liquids and clean char

    SciTech Connect (OSTI)

    Kruse, C.W.

    1991-01-01T23:59:59.000Z

    This integrated, multi-product approach for utilizing Illinois coal starts with the production of ultra low-ash coal and then converts it to high-vale, coal-derived, products. The ultra low-ash coal is produced by solubilizing coal in a phenolic solvent under ChemCoal{trademark} process conditions, separating the coal solution from insoluble ash, and then precipitating the clean coal by dilution of the solvent with methanol. Two major products, liquids and low-ash char, are then produced by mild gasification of the low-ash coal. The low ash-char is further upgraded to activated char, and/or an oxidized activated char which has catalytic properties. Characterization of products at each stage is part of this project.

  14. A review of ash in conventional and advanced coal-based power systems

    SciTech Connect (OSTI)

    Holcombe, N.T.

    1995-12-31T23:59:59.000Z

    Process conditions are briefly described for conventional and advanced power systems. The advanced systems include both combustion and gasification processes. We discuss problems in coal-based power generation systems, including deposition, agglomeration and sintering of bed materials, and ash attack are discussed. We also discuss methods of mitigating ash problems and anticipated changes anticipated in ash use by converting from conventional to advanced systems.

  15. INVESTIGATION OF AMMONIA ADSORPTION ON FLY ASH DUE TO INSTALLATION OF SELECTIVE CATALYTIC REDUCTION SYSTEMS

    SciTech Connect (OSTI)

    G.F. Brendel; J.E. Bonetti; R.F. Rathbone; R.N. Frey Jr.

    2000-11-01T23:59:59.000Z

    This report summarizes an investigation of the potential impacts associated with the utilization of selective catalytic reduction (SCR) systems at coal-fired power plants. The study was sponsored by the U.S. Department of Energy Emission Control By-Products Consortium, Dominion Generation, the University of Kentucky Center for Applied Energy Research and GAI Consultants, Inc. SCR systems are effective in reducing nitrogen oxides (NOx) emissions as required by the Clean Air Act (CAA) Amendments. However, there may be potential consequences associated with ammonia contamination of stack emissions and combustion by-products from these systems. Costs for air quality, landfill and pond environmental compliance may increase significantly and the marketability of ash may be seriously reduced, which, in turn, may also lead to increased disposal costs. The potential impacts to air, surface water, groundwater, ash disposal, ash utilization, health and safety, and environmental compliance can not be easily quantified based on the information presently available. The investigation included: (1) a review of information and data available from published and unpublished sources; (2) baseline ash characterization testing of ash samples produced from several central Appalachian high-volatile bituminous coals from plants that do not currently employ SCR systems in order to characterize the ash prior to ammonia exposure; (3) an investigation of ammonia release from fly ash, including leaching and thermal studies; and (4) an evaluation of the potential impacts on plant equipment, air quality, water quality, ash disposal operations, and ash marketing.

  16. Respirable aerosols from fluidized bed coal combustion. 3. Elemental composition of fly ash

    SciTech Connect (OSTI)

    Weissman, S.H.

    1983-02-01T23:59:59.000Z

    Trace element constituents in fly ash from an experimental atmospheric fluidized bed combustor (AFBC) are reported and compared with pulverized coal combustor (PCC) data and those from other fluidized bed combustors. Bulk and size-separated particles were collected and analyzed using spark source mass spectrometry. Fluidized bed combustion ash was similar to PCC ash in minor and trace element composition, but AFBC ash showed less size dependence of elemental composition. Bulk particle elemental composition varied with sampling position within the effluent stream. Penetration of elements through each cleanup stage and elemental enrichment were a function of the cleanup stage and the element under consideration.

  17. Coal deposit characterization by gamma-gamma density/percent dry ash relationships

    E-Print Network [OSTI]

    Wright, David Scott

    1984-01-01T23:59:59.000Z

    Density/Ash Relationship . APPLICATION OF THE GAMMA-GAMMA DENSITY/PERCENT DRY ASH RELATIONSHIPS The Density/Ash Relationship of a South Texas Lignite Deposit Characterization of a South Texas Lignite Deposit CONCLUSIONS REFERENCES. 52 53 53 53... 58 64 67 6g 80 87 LIST OF TABLES TABLE I Coal Classification by Rank. 2 Common Minerals in Coal. 3 Results of Linear Regression Analyses for a South Texas Lignite Deposit. 4 Variability of Geophysica11y-Derived Percent Dry Ash Values...

  18. Experimental and numerical analysis of metal leaching from fly ash-amended highway bases

    SciTech Connect (OSTI)

    Cetin, Bora [Department of Civil and Environmental Engineering, University of Maryland, College Park, MD 20742 (United States); Aydilek, Ahmet H., E-mail: aydilek@umd.edu [Department of Civil and Environmental Engineering, University of Maryland, College Park, MD 20742 (United States); Li, Lin [Department of Civil and Environmental Engineering, Jackson State University, Jackson, MS 17068 (United States)

    2012-05-15T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer This study is the evaluation of leaching potential of fly ash-lime mixed soils. Black-Right-Pointing-Pointer This objective is met with experimental and numerical analysis. Black-Right-Pointing-Pointer Zn leaching decreases with increase in fly ash content while Ba, B, Cu increases. Black-Right-Pointing-Pointer Decrease in lime content promoted leaching of Ba, B and Cu while Zn increases. Black-Right-Pointing-Pointer Numerical analysis predicted lower field metal concentrations. - Abstract: A study was conducted to evaluate the leaching potential of unpaved road materials (URM) mixed with lime activated high carbon fly ashes and to evaluate groundwater impacts of barium, boron, copper, and zinc leaching. This objective was met by a combination of batch water leach tests, column leach tests, and computer modeling. The laboratory tests were conducted on soil alone, fly ash alone, and URM-fly ash-lime kiln dust mixtures. The results indicated that an increase in fly ash and lime content has significant effects on leaching behavior of heavy metals from URM-fly ash mixture. An increase in fly ash content and a decrease in lime content promoted leaching of Ba, B and Cu whereas Zn leaching was primarily affected by the fly ash content. Numerically predicted field metal concentrations were significantly lower than the peak metal concentrations obtained in laboratory column leach tests, and field concentrations decreased with time and distance due to dispersion in soil vadose zone.

  19. Impurity-doped optical shock, detonation and damage location sensor

    DOE Patents [OSTI]

    Weiss, J.D.

    1995-02-07T23:59:59.000Z

    A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack. 8 figs.

  20. Impurity-doped optical shock, detonation and damage location sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    A shock, detonation, and damage location sensor providing continuous fiber-optic means of measuring shock speed and damage location, and could be designed through proper cabling to have virtually any desired crush pressure. The sensor has one or a plurality of parallel multimode optical fibers, or a singlemode fiber core, surrounded by an elongated cladding, doped along their entire length with impurities to fluoresce in response to light at a different wavelength entering one end of the fiber(s). The length of a fiber would be continuously shorted as it is progressively destroyed by a shock wave traveling parallel to its axis. The resulting backscattered and shifted light would eventually enter a detector and be converted into a proportional electrical signals which would be evaluated to determine shock velocity and damage location. The corresponding reduction in output, because of the shortening of the optical fibers, is used as it is received to determine the velocity and position of the shock front as a function of time. As a damage location sensor the sensor fiber cracks along with the structure to which it is mounted. The size of the resulting drop in detector output is indicative of the location of the crack.

  1. Carbon impurities on graphene synthesized by chemical vapor deposition on platinum

    SciTech Connect (OSTI)

    Ping, Jinglei; Fuhrer, Michael S., E-mail: michael.fuhrer@monash.edu [Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742-4111, USA and School of Physics, Monash University, 3800 Victoria (Australia)

    2014-07-28T23:59:59.000Z

    We report nanocrystalline carbon impurities coexisting with graphene synthesized via chemical vapor deposition on platinum. For certain growth conditions, we observe micron-size island-like impurity layers which can be mistaken for second graphene layers in optical microscopy or scanning electron microscopy. The island orientation depends on the crystalline orientation of the Pt, as shown by electron backscatter diffraction, indicating growth of carbon at the platinum surface below graphene. Dark-field transmission electron microscopy indicates that in addition to uniform single-crystal graphene, our sample is decorated with nanocrystalline carbon impurities with a spatially inhomogeneous distribution. The impurity concentration can be reduced significantly by lowering the growth temperature. Raman spectra show a large D peak, however, electrical characterization shows high mobility (?8000?cm{sup 2}/Vs), indicating a limitation for Raman spectroscopy in characterizing the electronic quality of graphene.

  2. Impurities in a non-axisymmetric plasma: transport and effect on bootstrap current

    E-Print Network [OSTI]

    Mollén, Albert; Smith, Håkan M; Braun, Stefanie; Helander, Per

    2015-01-01T23:59:59.000Z

    Impurities cause radiation losses and plasma dilution, and in stellarator plasmas the neoclassical ambipolar radial electric field is often unfavorable for avoiding strong impurity peaking. In this work we use a new continuum drift-kinetic solver, the SFINCS code (the Stellarator Fokker-Planck Iterative Neoclassical Conservative Solver) [M. Landreman et al., Phys. Plasmas 21 (2014) 042503] which employs the full linearized Fokker-Planck operator, to calculate neoclassical impurity transport coefficients for a Wendelstein 7-X (W7-X) magnetic configuration. We compare SFINCS calculations with theoretical asymptotes in the high collisionality limit. In intermediate and high collisionality regimes, a momentum conserving collision operator is critical to correctly determine the impurity transport coefficients, and a simple pitch-angle scattering approximation can lead to transport predictions in the wrong direction. In the low collisionality regime pitch-angle scattering is sufficient to accurately describe impuri...

  3. Development of NMR Methods for the Characterization of Heparin and its Impurities

    E-Print Network [OSTI]

    Limtiaco, John Francis Kuper

    2011-01-01T23:59:59.000Z

    Our HPLC-NMR method focuses on the WAX separation of intactThe weak anion exchange (WAX) method developed allows forof heparin impurities using WAX-HPLC, the characterization

  4. Final Report - Effects of Impurities on Fuel Cell Performance and Durability

    SciTech Connect (OSTI)

    Trent Molter

    2012-08-18T23:59:59.000Z

    This program is focused on the experimental determination of the effects of key hydrogen side impurities on the performance of PEM fuel cells. Experimental data has been leveraged to create mathematical models that predict the performance of PEM fuel cells that are exposed to specific impurity streams. These models are validated through laboratory experimentation and utilized to develop novel technologies for mitigating the effects of contamination on fuel cell performance. Results are publicly disseminated through papers, conference presentations, and other means.

  5. Instability in a uniform impurity distribution in a melt-grown silicon crystal

    SciTech Connect (OSTI)

    Rudenko, S.M.; Vasilevskii, M.I.; Golemshtok, G.M.

    1988-04-01T23:59:59.000Z

    Defect-distribution inhomogeneities occur in semiconductors even during crystal growth. The authors show that these can arise from instability in the dopant-semiconductor system. Many minor components enter silicon not only by substitution but also interstitially. They consider the scope for unstable states for a two-component impurity in a solid solution. Numerical stability calculations for inhomogeneous structures with various forms of impurity distribution are plotted.

  6. Contact formation and gettering of precipitated impurities by multiple firing during semiconductor device fabrication

    DOE Patents [OSTI]

    Sopori, Bhushan

    2014-05-27T23:59:59.000Z

    Methods for contact formation and gettering of precipitated impurities by multiple firing during semiconductor device fabrication are provided. In one embodiment, a method for fabricating an electrical semiconductor device comprises: a first step that includes gettering of impurities from a semiconductor wafer and forming a backsurface field; and a second step that includes forming a front contact for the semiconductor wafer, wherein the second step is performed after completion of the first step.

  7. Kinetics of fly ash beneficiation by carbon burnout. [Quarterly report], October 1, 1995--January 30, 1996

    SciTech Connect (OSTI)

    Dodoo, J.N.; Okoh, J.M.; Yilmaz, E.

    1996-09-01T23:59:59.000Z

    The objective is to investigate the kinetics of beneficiation of fly ash by carbon burnout. The three year project that was proposed is a joint venture between Delmarva Power, a power generating company on the eastern shore of Maryland, and the University of Maryland Eastern Shore. The studies have focused on the beneficiation of fly ash by carbon burnout. The increasing use of coal fly ash as pozzolanic material in Portland cement concrete means that there is the highest economic potential in marketability of large volumes of fly ash. For the concrete industry to consider large scale use the fly ash must be of the highest quality. This means that the residual carbon content of the fly ash must have an acceptable loss on ignition (LOI) value, usually between 7--2% residual carbon. The economic gains to be had from low-carbon ash is a fact that is generally accepted by the electricity generating companies. However, since the cost of producing low-carbon in large quantities, based on present technology, far outweighs any financial gains, no electrical power company using coal as its fuel at present considers the effort worthwhile. The concrete industry would use fly ash in cement concrete mix if it can be assured of its LOI value. At present no utility company would give such assurance. Hence with several million tons of fly ash produced by a single power plant per year all that can be done is to dump the fly ash in landfills. The kinetics of fly ash beneficiation have been investigated in the zone II kinetic regime, using a Cahn TG 121 microbalance in the temperature 550--750{degrees}C. The P{sub 02} and total surface area dependence of the reaction kinetics were determined using a vacuum accessory attached to the microbalance and a surface area analyzer (ASAP 2010), respectively.

  8. Static Consistency Checking for Distributed Specifications

    E-Print Network [OSTI]

    Finkelstein, Anthony

    Static Consistency Checking for Distributed Specifications Christian Nentwich, Wolfgang Emmerich, UK {c.nentwich,w.emmerich,a.finkelstein}@cs.ucl.ac.uk Abstract Software engineers building a complex

  9. Ash Fork, Arizona: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcatAntrimArkansas County,Minnesota:Arthur,Ascent SolarAscoenergyAsh

  10. Blue Ash, Ohio: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomass ConversionsSouthby 2022 |Bleckley County,Minnesota:Open EnergyAsh, Ohio:

  11. Biomonitoring of the genotoxic potential of aqueous extracts of soils and bottom ash resulting from municipal solid waste

    E-Print Network [OSTI]

    Mailhes, Corinne

    municipal solid waste incineration, using the comet and micronucleus tests on amphibian (Xenopus laevis ash resulting from municipal solid waste incineration (MSWIBA percolate), using amphibian larvae waste incineration bottom ash; Percolate 1. Introduction Environmental management of municipal solid

  12. Determination of Total Solids and Ash in Algal Biomass: Laboratory Analytical Procedure (LAP)

    SciTech Connect (OSTI)

    Van Wychen, S.; Laurens, L. M. L.

    2013-12-01T23:59:59.000Z

    This procedure describes the methods used to determine the amount of moisture or total solids present in a freeze-dried algal biomass sample, as well as the ash content. A traditional convection oven drying procedure is covered for total solids content, and a dry oxidation method at 575?C is covered for ash content.

  13. California bearing ratio behavior of soil-stabilized class F fly ash systems

    SciTech Connect (OSTI)

    Leelavathamma, B.; Mini, K.M.; Pandian, N.S. [Indian Institute for Science, Bangalore (India). Dept. for Civil Engineering

    2005-11-01T23:59:59.000Z

    Fly ash is a finely divided mineral residue resulting from the combustion of coal in power plants that occupies large extents of land and also causes environmental problems. Hence, concerted attempts are being made to effectively use fly ash in an environmentally friendly way instead of dumping. Several studies have been carried out for its bulk utilization, such as its addition to improve the California bearing ratio (CBR) of soil in roads and embankments. But a thorough mixing of fly ash with soil may not be possible in the field. Hence a study has been carried out on the CBR behavior of black cotton soil and Raichur fly ash (which is class F) in layers and compared with the same in mixes. The results show that the CBR values of soil-fly ash mixes are better than layers, as expected. To improve the strength of layers, cement is used as an additive to fly ash. The results show that black cotton soil can be improved with stabilized fly ash, solving its strength problem as well as the disposal problem of fly ash.

  14. Site-specific study on stabilization of acid-generating mine tailings using coal fly ash

    SciTech Connect (OSTI)

    Shang, J.Q.; Wang, H.L.; Kovac, V.; Fyfe, J. [University of Western Ontario, London, ON (Canada). Dept. of Civil & Environmental Engineering

    2006-03-15T23:59:59.000Z

    A site-specific study on stabilizing acid-generating mine tailings from Sudbury Mine using a coal fly ash from Nanticoke Generating Station is presented in this paper. The objective of the study is to evaluate the feasibility of codisposal of the fly ash and mine tailings to reduce environmental impacts of Sudbury tailings disposal sites. The study includes three phases, i.e., characterization of the mine tailings, and coal fly ash, oxidation tests on the mine tailings and kinetic column permeation tests. The results of the experiments indicate that when permeated with acid mine drainage, the hydraulic conductivity of Nanticoke coal fly ash decreased more than three orders of magnitude (from 1 x 10{sup -6} to 1 x 10{sup -9} cm/s), mainly due to chemical reactions between the ash solids and acid mine drainage. Furthermore, the hydraulic gradient required for acid mine drainage to break through the coal fly ash is increased up to ten times (from 17 to 150) as compared with that for water. The results also show that the leachate from coal fly ash neutralizes the acidic pore fluid of mine tailings. The concentrations of trace elements in effluents from all kinetic column permeation tests indicated that coplacement of coal fly ash with mine tailings has the benefit of immobilizing trace elements, especially heavy metals. All regulated element concentrations from effluent during testing are well below the leachate quality criteria set by the local regulatory authority.

  15. Market Assessment and Technical Feasibility Study of Pressurized Fluidized Bed Combustion Ash Use

    SciTech Connect (OSTI)

    Bland, A.E.; Brown, T.H. [Western Research Inst., Laramie, WY (United States)

    1996-12-31T23:59:59.000Z

    Western Research Institute in conjunction with the Electric Power Research Institute, Foster Wheeler Energy International, Inc. and the U.S. Department of Energy Technology Center (METC), has undertaken a research and demonstration program designed to examine the market potential and the technical feasibility of ash use options for pressurized fluidized bed combustion (PFBC) ashes. The assessment is designed to address six applications, including: (1) structural fill, (2) road base construction, (3) supplementary cementing materials in portland cement, (4) synthetic aggregate, and (5) agricultural/soil amendment applications. Ash from low-sulfur subbituminous coal-fired Foster Wheeler Energia Oy pilot circulating PFBC tests in Karhula, Finland, and ash from the high-sulfur bituminous coal-fired American Electric Power (AEP) bubbling PFBC in Brilliant, Ohio, were evaluated in laboratory and pilot-scale ash use testing. This paper addresses the technical feasibility of ash use options for PFBC unit using low- sulfur coal and limestone sorbent (karhula ash) and high-sulfur coal and dolomite sorbents (AEP Tidd ash).

  16. Issues with the Use of Fly Ash for Carbon Sequestration A.V. Palumbo1*

    E-Print Network [OSTI]

    Tiquia-Arashiro, Sonia M.

    Issues with the Use of Fly Ash for Carbon Sequestration A.V. Palumbo1* , L. S. Fisher1 , J of the potential for carbon sequestration in degraded mine lands, we have found that based on laboratory and field and its influence on carbon sequestration. Also, addition of fly ash to soil, while generally considered

  17. Emission Control Technology, Performance/Durability -POSTER Effect of Accelerated Ash Loading on Performance of Diesel

    E-Print Network [OSTI]

    Pennycook, Steve

    on Performance of Diesel Particulate Filters and Morphology of Ash Layers Bruce G. Bunting and Todd J. Toops using a single-cylinder diesel engine has been developed for accelerated ash loading in catalyzed and non- catalyzed diesel particular filters (DPF) made of cordierite, SiC and mullite substrate

  18. MULTIPLE-SCALE DYNAMIC LEACHING OF A MUNICIPAL SOLID WASTE INCINERATION ASH

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 MULTIPLE-SCALE DYNAMIC LEACHING OF A MUNICIPAL SOLID WASTE INCINERATION ASH Waste Management (in source such as municipal solid waste (MSW) incineration ash, requires a knowledge of the so percolating through waste evolve over time, for a given percolation scenario (infiltration rate, waste source

  19. Color Removal from Pulp Mill Effluent Using Coal Ash Produced from Georgia Coal Combustion Power Plants

    E-Print Network [OSTI]

    Hutcheon, James M.

    permits. To improve the aesthetic qualities of the effluent, coal ash (from local power plants_mill_discharge.jpg 2. Coal Power Plant http://www.csmonitor.com/var/ezflow_site/storage/images/media/images/2008Color Removal from Pulp Mill Effluent Using Coal Ash Produced from Georgia Coal Combustion Power

  20. Soil stabilization using optimum quantity of calcium chloride with Class F fly ash 

    E-Print Network [OSTI]

    Choi, Hyung Jun

    2006-10-30T23:59:59.000Z

    in soil to verify the effectiveness and optimum ratio of calcium chloride and Class F fly ash in soil stabilization. Mix design was programmed at pure calcium chloride concentrations at 0% to 6% and Class F fly ash at 10 to 15%. Laboratory tests showed...

  1. Separation and Purification Technology 40 (2004) 251257 Copper and zinc sorption by treated oil shale ash

    E-Print Network [OSTI]

    Shawabkeh, Reyad A.

    2004-01-01T23:59:59.000Z

    Jordanian oil shale ash was used as an adsorbent for the removal of copper and zinc from aqueous solution.V. All rights reserved. Keywords: Oil shale; Ash; Adsorption; Copper and zinc removal 1. IntroductionSeparation and Purification Technology 40 (2004) 251­257 Copper and zinc sorption by treated oil

  2. Canopy, litter and allelopathic effects of Ashe juniper (Juniperus ashei, Buchholz) on understory vegetation

    E-Print Network [OSTI]

    Yager, Lisa Yvonne

    1993-01-01T23:59:59.000Z

    , subirrigated litter treatment, and surface watered litter treatment. . 87 Figure 12 Drying rates of Ashe juniper litter when watered every 2, 3, and 4 days. . 92 LIST OF TABLES Table Page 1 Field treatments to test the influence of Ashe juniper canopy...

  3. Experimental and numerical analysis of metal leaching from fly ash-amended highway bases

    E-Print Network [OSTI]

    Aydilek, Ahmet

    December 2011 Available online xxxx Keywords: Coal combustion by products Fly ash Heavy metals Leaching road materials (URM) mixed with lime activated high carbon fly ashes and to evaluate groundwater is produced in the United States as a by-product of burning coal in electric power plants (ACAA, 2009

  4. Ash, calcium, phosphorus and magnesium content of the metacarpus of hereford cows under different nutritional and physiological conditions 

    E-Print Network [OSTI]

    Haque, Mozammel

    1967-01-01T23:59:59.000Z

    ASH, CALCIUM, PHOSPHORUS AND MAGNESIUM CONTENT OF THE METACARPUS OF HEREFORD COWS UNDER DIFFERENT NUTRITIONAL AND PHYSIOLOGICAL CONDITIONS A Thesis By MOZAMMEL HAQUE Submitted to the Graduate College of the Texas A&M University in partial... centages of Calcium, Phosphorus snd Magnesium in Bone Ash for Cows Gi;en Different Treatments During Pre- And Post-Partum Periods 22 10 Analysis of Variance oi Calcium in Bone Ash Dun an's )tultiple tvange Test 1'or Calcium in Bone Ash. Analy...

  5. pH-dependent leaching of dump coal ash - retrospective environmental analysis

    SciTech Connect (OSTI)

    Popovic, A.; Djordjevic, D. [University of Belgrade, Belgrade (Serbia). Dept. of Chemistry

    2009-07-01T23:59:59.000Z

    Trace and major elements in coal ash particles from dump of 'Nikola Tesla A' power plant in Obrenovac near Belgrade (Serbia) can cause pollution, due to leaching by atmospheric and surface waters. In order to assess this leaching potential, dump ash samples were subjected to extraction with solutions of decreasing pH values (8.50, 7.00, 5.50, and 4.00), imitating the reactions of the alkaline ash particles with the possible alkaline, neutral, and acidic (e.g., acid rain) waters. The most recently deposited ash represents the greatest environmental threat, while 'aged' ash, because of permanent leaching on the dump, was shown to have already lost this pollution potential. On the basis of the determined leachability, it was possible to perform an estimation of the acidity of the regional rainfalls in the last decades.

  6. Treatment technologies for hazardous ashes generated from possible incineration of navy waste. Technical note

    SciTech Connect (OSTI)

    Torres, T.

    1990-10-01T23:59:59.000Z

    The Navy recognizes that thermal treatment of Navy hazardous wastes (HW) should, under the terms of the Resource Conservation and Recovery Act of 1976, be avoided. Combustion waste disposal may nonetheless become unavoidable in certain cases, even after all possible process enhancements that avoid HW production are implemented. Even then, some toxic constituents that may be present in the waste will not be destroyed by incineration and will persist in the ash residue produced by incineration. Such incinerator ashes will have to be disposed of in HW landfills. The Navy is thus evaluating methods of treatment of such ash to remove or immobilize the toxic constituents that persist following incineration in order to render the waste treatment residue nonhazardous. Appropriate technology identified in this work can be applied to ash produced by HW combuster operated by the Navy, if any, or be required for ash produced by commercial generators handling Navy HWs.

  7. Use of rubber and bentonite added fly ash as a liner material

    SciTech Connect (OSTI)

    Cokca, Erdal; Yilmaz, Zeka

    2004-07-01T23:59:59.000Z

    In many countries regulations require all hazardous waste disposal facilities to be lined with suitable impermeable barriers to protect against contamination. In this study, a series of laboratory tests on rubber and bentonite added fly ash were conducted. The aim of the tests was to evaluate the feasibility of utilizing fly ash, rubber and bentonite as a low hydraulic conductivity liner material. Type C fly ash was obtained from Soma thermal power plant in Turkey; rubber in pulverized form was waste from the retreading industry. To investigate the properties of rubber and bentonite added fly ash, hydraulic conductivity, leachate analysis, unconfined compression, split tensile strength, one-dimensional consolidation, swell and freeze/thaw cycle tests were performed. The overall evaluation of results have revealed that rubber and bentonite added fly ash showed good promise and a candidate for construction of a liner.

  8. In situ analysis of ash deposits from black liquor combustion

    SciTech Connect (OSTI)

    Bernath, P. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Toronto, Ontario (Canada); Sinquefield, S.A. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Oregon State Univ., Eugene, OR (United States); Baxter, L.L.; Sclippa, G.; Rohlfing, C. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Barfield, M. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Arizona, Tucson, AZ (United States)

    1996-05-01T23:59:59.000Z

    Aerosols formed during combustion of black liquor cause a significant fire-side fouling problem in pulp mill recovery boilers. The ash deposits reduce heat transfer effectiveness, plug gas passages, and contribute to corrosion. Both vapors and condensation aerosols lead to the formation of such deposits. The high ash content of the fuel and the low dew point of the condensate salts lead to a high aerosol and vapor concentration in most boilers. In situ measurements of the chemical composition of these deposits is an important step in gaining a fundamental understanding of the deposition process. Infrared emission spectroscopy is used to characterize the composition of thin film deposits resulting from the combustion of black liquor and the deposition of submicron aerosols and vapors. New reference spectra of Na{sub 2}SO{sub 4}, K{sub 2}SO{sub 4}, Na{sub 2}CO{sub 3} and K{sub 2}CO{sub 3} pure component films were recorded and compared with the spectra of the black liquor deposit. All of the black liquor emission bands were identified using a combination of literature data and ab initio calculations. Ab initio calculations also predict the locations and intensities of bands for the alkali vapors of interest. 39 refs., 9 figs.

  9. Evaluation of rice husk ash as filler in tread compounds

    SciTech Connect (OSTI)

    Fernandes, M. R. S., E-mail: monica.fernandes@lanxess.com [Lanxess Elastômeros do Brasil S.A., Brasil and Instituto de Química, Universidade do Estado do Rio de Janeiro (UERJ) (Brazil); Furtado, C. R. G., E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com; Sousa, A. M. F. de, E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com [Instituto de Química, Universidade do Estado do Rio de Janeiro (UERJ) (Brazil)

    2014-05-15T23:59:59.000Z

    Rice which is one of the largest agriculture crops produces around 22% of rice rusk during its milling process. This material is mainly used as fuel for energy generation, which results in an ash, which disposal represents an environmental issue. The rice husk ash (RHA) contains over than 70% of silica in an amorphous form and a lot of applications is being developed for it all over the world. The use of silica as a filler in the tire industry is growing since it contributes significantly to the reduction of fuel consumption of the automobiles, allowing at the same time better traction (safety). This paper presents an evaluation of the use of RHA as filler in rubber tread compounds prepared in lab scale and compares its performance with compounds prepared with commercial silica and carbon black, the fillers normally used in tire industry. Mechanical and rheological properties are evaluated, with emphasis for tan delta as an indicator of tread performance related with rolling resistance (fuel consumption) and wet grip/traction (safety)

  10. Coal fly ash basins as an attractive nuisance to birds: Parental provisioning exposes nestlings to harmful trace elements

    E-Print Network [OSTI]

    Hopkins, William A.

    inhabiting settling impoundments receiving slurried ash from a coal-fired power plant located on the U. SCoal fly ash basins as an attractive nuisance to birds: Parental provisioning exposes nestlings Keywords: Coal fly ash basin Common Grackle Contaminants Quiscalus quiscala Selenium a b s t r a c t Birds

  11. Evaluation of the effects of coal fly ash amendments on the toxicity of a contaminated marine sediment

    SciTech Connect (OSTI)

    Burgess, R.M.; Perron, M.M.; Friedman, C.L.; Suuberg, E.M.; Pennell, K.G.; Cantwell, M.G.; Pelletier, M.C.; Ho, K.T.; Serbst, J.R.; Ryba, S.A. [US EPA, Narragansett, RI (USA). Office for Research and Development

    2009-01-15T23:59:59.000Z

    Approaches for cleaning up contaminated sediments range from dredging to in situ treatment. In this study, we discuss the effects of amending reference and contaminated sediments with coal fly ash to reduce the bioavailability and toxicity of a field sediment contaminated with polycyclic aromatic hydrocarbons (PAHs). Six fly ashes and a coconut charcoal were evaluated in 7-d whole sediment toxicity tests with a marine amphipod (Ampelisca abdita) and mysid (Americamysis bahia). Fly ashes with high carbon content and the coconut charcoal showed proficiency at reducing toxicity. Some of the fly ashes demonstrated toxicity in the reference treatments. It is suspected that some of this toxicity is related to the presence of ammonia associated with fly ashes as a result of postoxidation treatment to reduce nitrous oxide emissions. Relatively simple methods exist to remove ammonia from fly ash before use, and fly ashes with low ammonia content are available. Fly ashes were also shown to effectively reduce overlying water concentrations of several PAHs. No evidence was seen of the release of the metals cadmium, copper, nickel, or lead from the fly ashes. A preliminary 28-d polychaete bioaccumulation study with one of the high-carbon fly ashes and a reference sediment was also performed. Although preliminary, no evidence was seen of adverse effects to worm growth or lipid content or of accumulation of PAHs or mercury from exposure to the fly ash. These data show fly ashes with high carbon content could represent viable remedial materials for reducing the bioavailability of organic contaminants in sediments.

  12. J. Marshall Ash Proceedings of the American Mathematical Society, Vol. 108, No. 2. (Feb., 1990), p. 571.

    E-Print Network [OSTI]

    Ash, J. Marshall

    Erratum J. Marshall Ash Proceedings of the American Mathematical Society, Vol. 108, No. 2. (Feb, February 1990 ERRATUM J. MARSHALL ASH The paper "A new proof of uniqueness for multiple trigonometric series" by J. Marshall Ash, which appeared in 107(2) October 1989, should have been entitled "A new proof

  13. County looks at turning waste ash into money Two companies using grant to investigate ways to recycle incinerator byproduct

    E-Print Network [OSTI]

    Columbia University

    in York County generates about 160,000 tons of ash per year, and attempts to dispose of it have caused Technology Inc. will seek to use the ash in synthetic stones called Brixx, which also re-use coal wasteCounty looks at turning waste ash into money Two companies using grant to investigate ways

  14. Feasible experimental study on the utilization of a 300 MW CFB boiler desulfurizating bottom ash for construction applications

    SciTech Connect (OSTI)

    Lu, X.F.; Amano, R.S. [University of Wisconsin, Milwaukee, WI (United States). Dept. of Mechanical Engineering

    2006-12-15T23:59:59.000Z

    CFB boiler ash cannot be used as a cement replacement in concrete due to its unacceptably high sulfur content. The disposal in landfills has been the most common means of handling ash in circulating fluidized bed boiler power plants. However for a 300 MW CFB boiler power plant, there will be 600,000 tons of ash discharged per year and will result in great volumes and disposal cost of ash byproduct. It was very necessary to solve the utilization of CFB ash and to decrease the disposal cost of CFB ash. The feasible experimental study results on the utilization of the bottom ashes of a 300 MW CFB boiler in Baima power plant in China were reported in this paper. The bottom ashes used for test came from the discharged bottom ashes in a 100 MW CFB boiler in which the anthracite and limestone designed for the 300 MW CFB project was burned. The results of this study showed that the bottom ash could be used for cementitious material, road concrete, and road base material. The masonry cements, road concrete with 30 MPa compressive strength and 4.0 MPa flexural strength, and the road base material used for base courses of the expressway, the main road and the minor lane were all prepared with milled CFB bottom ashes in the lab. The better methods of utilization of the bottom ashes were discussed in this paper.

  15. Metal Bioavailability and Speciation in a Wetland Tailings Repository Amended with Biosolids Compost, Wood Ash, and Sulfate

    E-Print Network [OSTI]

    Brown, Sally

    Compost, Wood Ash, and Sulfate Pam S. DeVolder, Sally L. Brown,* Dean Hesterberg, and Kumi Pandya ABSTRACT tundra swans surface amendments: (i) biosolids compost plus wood ash, (ii) and other animals found in the area have tested positive compost wood ash a low SO2 4 addition as K2SO4, and (iii) for Pb poisoning

  16. Kinetics of fly ash beneficiation by carbon burnout. Quarterly report, January--March 1996

    SciTech Connect (OSTI)

    Dodoo, J.N.; Okoh, J.M.; Yilmaz, E.

    1996-09-01T23:59:59.000Z

    The three year project that was proposed is a joint venture between Delmarva Power, a power generating company on the eastern shore of Maryland, and the University of Maryland Eastern Shore. The studies have focused on the benefication of fly ash by carbon burnout. The increasing use of coal fly ash as pozzolanic material in Portland cement concrete means that there is the highest economic potential in marketability of large volumes of fly ash. For the concrete industry to consider large scale use the fly ash must be of the highest quality. This means that the residual carbon content of the fly ash must have an acceptable loss on ignition (LOI) value, usually between 7-2% residual carbon. The economic gains to be had from low-carbon ash is a fact that is generally accepted by the electricity generating companies. However, since the cost of producing low-carbon in large quantities, based on present technology, far outweighs any financial gains, no electrical power company using coal as its fuel at present considers the effort worthwhile. The concrete industry would use fly ash in cement concrete mix if it can be assured of its LOI value. At present no utility company would give such assurance. Hence with several million tons of fly ash produced by a single power plant per year all that can be done is to dump the fly ash in landfills. The kinetics of fly ash benefication have been investigated in the zone II kinetic regime, using a Cahn TG 121 microbalance in the temperature 550-750{degrees}C. The P{sub O{sub 2}} and total surface area dependence of the reaction kinetics were determined using a vacuum accessory attached to the microbalance and a surface area analyzer (ASAP 2010), respectively. 16 refs., 7 figs., 3 tabs.

  17. GLYCOLIC ACID PHYSICAL PROPERTIES, IMPURITIES, AND RADIATION EFFECTS ASSESSMENT

    SciTech Connect (OSTI)

    Lambert, D.; Pickenheim, B.; Hay, M.

    2011-06-20T23:59:59.000Z

    The Defense Waste Processing Facility (DWPF) is pursuing alternative reductants/flowsheets to increase attainment to meet closure commitment dates. In fiscal year 2009, SRNL evaluated several options and recommended the further assessment of the nitric/formic/glycolic acid flowsheet. SRNL is currently performing testing with this flowsheet to support the DWPF down-select of alternate reductants. As part of the evaluation, SRNL was requested to determine the physical properties of formic and glycolic acid blends. Blends of formic acid in glycolic acid were prepared and their physical properties tested. Increasing amounts of glycolic acid led to increases in blend density, viscosity and surface tension as compared to the 90 wt% formic acid that is currently used at DWPF. These increases are small, however, and are not expected to present any difficulties in terms of processing. The effect of sulfur impurities in technical grade glycolic acid was studied for its impact on DWPF glass quality. While the glycolic acid specification allows for more sulfate than the current formic acid specification, the ultimate impact is expected to be on the order of 0.03 wt% sulfur in glass. Note that lower sulfur content glycolic acid could likely be procured at some increased cost if deemed necessary. A paper study on the effects of radiation on glycolic acid was performed. The analysis indicates that substitution of glycolic acid for formic acid would not increase the radiolytic production rate of H{sub 2} and cause an adverse effect in the SRAT or SME process. It has been cited that glycolic acid solutions that are depleted of O{sub 2} when subjected to large radiation doses produced considerable quantities of a non-diffusive polymeric material. Considering a constant air purge is maintained in the SRAT and the solution is continuously mixed, oxygen depletion seems unlikely, however, if this polymer is formed in the SRAT solution, the rheology of the solution may be affected and pumping of the solution may be hindered. However, an irradiation test with a simulated SRAT product supernate containing glycolic acid in an oxygen depleted atmosphere found no evidence of polymerization.

  18. Consistent nonlinear dynamics: identifying model inadequacy

    E-Print Network [OSTI]

    Patrick E. McSharry; Leonard A. Smith

    2004-03-09T23:59:59.000Z

    Empirical modelling often aims for the simplest model consistent with the data. A new technique is presented which quantifies the consistency of the model dynamics as a function of location in state space. As is well-known, traditional statistics of nonlinear models like root-mean-square (RMS) forecast error can prove misleading. Testing consistency is shown to overcome some of the deficiencies of RMS error, both within the perfect model scenario and when applied to data from several physical systems using previously published models. In particular, testing for consistent nonlinear dynamics provides insight towards (i) identifying when a delay reconstruction fails to be an embedding, (ii) allowing state dependent model selection and (iii) optimising local neighbourhood size. It also provides a more relevant (state dependent) threshold for identifying false nearest neighbours.

  19. Evaluating the Effects of the Kingston Fly Ash Release on Fish Reproduction: Spring 2009 - 2010 Studies

    SciTech Connect (OSTI)

    Greeley Jr, Mark Stephen [ORNL; Adams, Marshall [ORNL; McCracken, Kitty [ORNL

    2012-05-01T23:59:59.000Z

    On December 22, 2008, a dike containing fly ash and bottom ash at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits from the spill extended 4 miles upstream of the facility to Emory River mile 6 and downstream to Tennessee River mile 564 ({approx}8.5 miles downstream of the confluence of the Emory River with the Clinch River, and {approx}4 miles downstream of the confluence of the Clinch River with the Tennessee River). A byproduct of coal combustion, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be harmful to biological systems. The ecological effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to come from elevated levels of certain metals in the ash, particularly selenium, on fish reproduction and fish early life stages (Lemly 1993; Besser and others 1996). The ovaries of adult female fish in a lake contaminated by coal ash were reported to have an increased frequency of atretic oocytes (dead or damaged immature eggs) and reductions in the overall numbers of developing oocytes (Sorensen 1988) associated with elevated body burdens of selenium. Larval fish exposed to selenium through maternal transfer of contaminants to developing eggs in either contaminated bodies of water (Lemly 1999) or in experimental laboratory exposures (Woock and others 1987, Jezierska and others 2009) have significantly increased incidences of developmental abnormalities. Contact of fertilized eggs and developing embryos to ash in water and sediments may also pose an additional risk to the early life stages of exposed fish populations through direct uptake of metals and other ash constituents (Jezierska and others 2009). The establishment and maintenance of fish populations is intimately associated with the ability of individuals within a population to reproduce. Reproduction is thus generally considered to be the most critical life function affected by environmental contamination. From a regulatory perspective, the issue of potential contaminant-related effects on fish reproduction from the Kingston fly ash spill has particular significance because the growth and propagation of fish and other aquatic life is a specific classified use of the affected river systems. To address the potential effects of fly ash from the Kingston spill on the reproductive health of exposed fish populations, ORNL has undertaken a series of studies in collaboration with TVA that include: (1) a combined field study of metal bioaccumulation in ovaries and other fish tissues (Adams and others 2012) and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill (the current report); (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (Greeley and others 2012); (3) additional laboratory experimentation focused on the potential effects of long-term exposures to fly ash on fish survival and reproductive competence (unpublished); and (4) a combined field and laboratory study examining the in vitro developmental success of embryos and larvae obtained from fish exposed in vivo for over two years to fly ash in the Emory and Clinch Rivers (unpublished). The current report focuses on the reproductive condition of adult female fish in reaches of the Emory and Clinch Rivers influenced by the fly ash spill at the beginning of the spring 2009 breeding season - the first breeding season immediately following the fly ash release - and during the subsequent spring 2010 breeding season. Data generated from this and related reproductive/early life stage studies provide direct input to ecological risk assessment efforts and complement and support other phases of the overall biomonitoring program associated with the fly ash spill.

  20. Characterization of ash deposition and heat transfer behavior of coals during combustion in a pilot-scale facility and full-scale utility

    SciTech Connect (OSTI)

    Sushil Gupta; Rajender Gupta; Gary Bryant; Terry Wall; Shinji Watanabe; Takashi Kiga; Kimihito Narukawa [University of New South Wales, Sydney, NSW (Australia). Centre for Sustainable Materials Research & Technology

    2009-05-15T23:59:59.000Z

    Experimental measurements as well as theoretical models were used to investigate the impact of mineral matter of three coals on ash deposition and heat transfer for pulverized coal fired boilers. The ash deposition experiments were conducted in a pulverized fuel combustion pilot-scale facility and a full-scale unit. A mathematical model with input from computer-controlled scanning electron microscopy analysis of coal minerals was used to predict the effect of ash deposition on heat transfer. The predicted deposit thickness and heat flux from the model are shown to be consistent with the measurements in the test facility. The model differentiates the coals according to the deposits they form and their effect on heat transfer. The heat transfer predictions in the full-scale unit were found to be most suitable for the water wall under the furnace nose. The study demonstrates that the measurements in a full-scale unit can differ significantly from those in pilot-scale furnaces due to soot-blowing operations. 9 refs., 12 figs., 3 tabs.

  1. Discussion of and reply to ``The characteristics of two-stage municipal combustor ash (Example: Harford County resource recovery facility in Maryland)``

    SciTech Connect (OSTI)

    Eppich, J.D. [HDR Engineering, Irvine, CA (United States); Hecklinger, R.S. [Roy F. Weston, Inc., Valhalla, NY (United States); Winka, M. [NJDEP/DSWM, Trenton, NJ (United States); Feindler, K.S. [Beaumont Environmental Inc., Wheatley Heights, NY (United States)

    1995-11-01T23:59:59.000Z

    This paper, by Klaus S. Feindler, is a good contribution to the understanding of two-stage municipal combustors. He has mixed and quartered the ash from the one-half inch by one-half inch under stream in accordance with ASTM-D346-78. It is suggested that this mixing and quartering procedure be used earlier in the field processing procedure. Also, with a high level of consistently good annual performance, why was there such a concern with the month-to-month SAR? There is hardly any mention of the fact that continuously-fired, two-stage combustors produce a heavy loading of fixed carbon in the furnace residue and a high unburned combustible loss. Rather, the paper draws a number of conclusions from a small amount of test data. In addition, some of the data appear to have been incorrectly interpreted. Additional information is requested on the following: mass balancing of the facility; ash sampling; correlation of operational data to lab data; ash model/solid waste model calibration/validation; and improvement/Test I data. This article also contains the original author`s reply to the comments and questions.

  2. Impurity and gender in the Hebrew Bible : ideological intersections in the books of Leviticus, Ezekiel and Ezra

    E-Print Network [OSTI]

    Goldstein, Elizabeth Wayne

    2010-01-01T23:59:59.000Z

    de Troyer et al. eds. ; Harrisburg: Trinity Press, 2003) 29-of Purity and Impurity (Harrisburg, PA: Trinity Pressand A. Korte. Harrisburg: Trinity Press International, 2003.

  3. Density functional theory calculations of stability and diffusion mechanisms of impurity atoms in Ge crystals

    SciTech Connect (OSTI)

    Maeta, Takahiro [Graduate School of System Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197 (Japan); GlobalWafers Japan Co., Ltd., Higashikou, Seirou-machi, Kitakanbara-gun, Niigata 957-0197 (Japan); Sueoka, Koji [Department of Communication Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197 (Japan)

    2014-08-21T23:59:59.000Z

    Ge-based substrates are being developed for applications in advanced nano-electronic devices because of their higher intrinsic carrier mobility than Si. The stability and diffusion mechanism of impurity atoms in Ge are not well known in contrast to those of Si. Systematic studies of the stable sites of 2nd to 6th row element impurity atoms in Ge crystal were undertaken with density functional theory (DFT) and compared with those in Si crystal. It was found that most of the impurity atoms in Ge were stable at substitutional sites, while transition metals in Si were stable at interstitial sites and the other impurity atoms in Si were stable at substitutional sites. Furthermore, DFT calculations were carried out to clarify the mechanism responsible for the diffusion of impurity atoms in Ge crystals. The diffusion mechanism for 3d transition metals in Ge was found to be an interstitial-substitutional diffusion mechanism, while in Si this was an interstitial diffusion mechanism. The diffusion barriers in the proposed diffusion mechanisms in Ge and Si were quantitatively verified by comparing them to the experimental values in the literature.

  4. Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures

    DOE Patents [OSTI]

    Khan, M. Rashid (Morgantown, WV)

    1990-01-01T23:59:59.000Z

    A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

  5. Investigation of Fly Ash and Activated Carbon Obtained from Pulverized Coal Boilers

    SciTech Connect (OSTI)

    Edward K. Levy; Christopher Kiely; Zheng Yao

    2006-08-31T23:59:59.000Z

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addressed the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addressed the possible connection between SCR reactors, fly ash properties and Hg capture. The project has determined the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed have also been determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control have been analyzed in an effort to determine the effects of SCR on the ash.

  6. Regeneratively cooled coal combustor/gasifier with integral dry ash removal

    DOE Patents [OSTI]

    Beaufrere, Albert H. (Huntington, NY)

    1983-10-04T23:59:59.000Z

    A coal combustor/gasifier is disclosed which produces a low or medium combustion gas for further combustion in modified oil or gas fired furnaces or boilers. Two concentric shells define a combustion volume within the inner shell and a plenum between them through which combustion air flows to provide regenerative cooling of the inner shell for dry ash operation. A fuel flow and a combustion air flow having opposed swirls are mixed and burned in a mixing-combustion portion of the combustion volume and the ash laden combustion products flow with a residual swirl into an ash separation region. The ash is cooled below the fusion temperature and is moved to the wall by centrifugal force where it is entrained in the cool wall boundary layer. The boundary layer is stabilized against ash re-entrainment as it is moved to an ash removal annulus by a flow of air from the plenum through slots in the inner shell, and by suction on an ash removal skimmer slot.

  7. A new method on recycling coefficient measurement using impurity pellet injection in a large helical device

    SciTech Connect (OSTI)

    Nozato, Hideaki; Morita, Shigeru; Goto, Motoshi [Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

    2005-07-15T23:59:59.000Z

    Recycling coefficients of carbon, aluminum, and titanium were evaluated using a new technique combining impurity pellet injection with high-spatial resolution bremsstrahlung measurement in hydrogen and helium plasmas on the large helical device. The recycling coefficient of impurities was investigated by measuring absolute intensities with the visible bremsstrahlung array. The time evolution of the bremsstrahlung signals was modeled by an impurity transport code adjusting the diffusion coefficient, convective velocity, and recycling coefficient. As a result, a finite value of the recycling coefficient was required in the case of carbon, whereas aluminum and titanium were explained as nonrecycled particles. It was also clarified that the recycling coefficient of carbon had a larger value in hydrogen plasmas (R=0.5-0.65) than in helium plasmas (R=0-0.2), suggesting the formation of hydrogen molecules.

  8. Petrography and chemistry of sized fly ash from low-sulfur and high-sulfur coal sources

    SciTech Connect (OSTI)

    Hower, J.C. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Trimble, A.S. [Franklin County High School, Frankfort, KY (United States); Eble, C.F. [Kentucky Geological Survey, Lexington, KY (United States); Palmer, C. [Geological Survey, Reston, VA (United States)

    1996-12-31T23:59:59.000Z

    Fly ash samples were collected in November and December, 1994, from two units representing high- and low-sulfur feed coals at a Kentucky power station. The ashes were wet screened at 100, 200, 325, and 500 mesh. The dried ({approximately}40 C) fractions were then weighed, split for petrographic and chemical analysis, mounted in epoxy and prepared as polished pellets, and analyzed for ash yield and carbon content. The November ashes had a similar size distribution in the +325 mesh fractions. The low-sulfur hot side and cool side ashes had a similar size distribution in the November ashes. In contrast, the December fly ashes showed the typical trend, the cool-side ash being finer (over 20% more ash in the {minus}500 mesh fraction) than the hot-side ash. Carbon tends to be relatively concentrated in the coarse fractions. The dominance of the {minus}325 mesh fractions in the overall size analysis implies, though, that carbon in the fine sizes is an important consideration in the utilization potential of the fly ash.

  9. Scale-Up and Demonstration of Fly Ash Oxonation Technology

    SciTech Connect (OSTI)

    Larry LaBuz; Rui Afonso

    2005-06-30T23:59:59.000Z

    This is the fifth quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the fifth quarterly report and it refers to the time period from April-July 2005. (An additional month is included in this quarterly report as we have been in a data analyses mode and wanted to provide new data relative to the previous report). During this period, the project team has been reviewing and analyzing data from the onsite ozonation tests, as well as conducting additional laboratory ash and concrete tests. This report summarizes these activities including some preliminary results. No significant issues or concerns are identified.

  10. Spectroscopic investigation of heavy impurity behaviour during ICRH with the JET ITER-like wall

    SciTech Connect (OSTI)

    Czarnecka, A. [Institute of Plasma Physics and Laser Microfusion, Association EURATOM-IPPLM, Hery 23 Str., 01-497 Warsaw (Poland); Bobkov, V.; Maggi, C.; Pütterich, T. [Max-Planck-Institut für Plasmaphysik, EURATOM-Association, D-85748 Garching (Germany); Coffey, I. H. [Department of Physics, Queen's University, Belfast, BT7 1NN, Northern Ireland (United Kingdom); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Jacquet, P.; Lawson, K. D. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Lerche, E.; Van Eester, D. [Association EURATOM - Belgian State, ERM-KMS, TEC Partner (Belgium); Mayoral, M.-L. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB, UK and EFDA Close Support Unit, Garching (Germany); Collaboration: JET-EFDA Contributors

    2014-02-12T23:59:59.000Z

    Magnetically confined plasmas, such as those produced in the tokamak JET, contain measurable amounts of impurity ions produced during plasma-wall interactions (PWI) from the plasma-facing components and recessed wall areas. The impurities, including high- and mid-Z elements such as tungsten (W) from first wall tiles and nickel (Ni) from Inconel structure material, need to be controlled within tolerable limits, to ensure they do not significantly affect the performance of the plasma. This contribution focuses on documenting W and Ni impurity behavior during Ion Cyclotron Resonance Heating (ICRH) operation with the new ITER-Like Wall (ILW). Ni- and W-concentration were derived from VUV spectroscopy and the impact of applied power level, relative phasing of the antenna straps, plasma separatrix - antenna strap distance, IC resonance position, edge density and different plasma configuration, on the impurity release during ICRH are presented. For the same ICRH power the Ni and W concentration was lower with dipole phasing than in the case of ??/2 phasing. The Ni concentration was found to increase with ICRH power and for the same NBI power level, ICRH-heated plasmas were characterized by two times higher Ni impurity content. Both W and Ni concentrations increased strongly with decreasing edge density which is equivalent to higher edge electron temperatures and more energetic ions responsible for the sputtering. In either case higher levels were found in ICRH than in NBI heated discharges. When the central plasma temperature was similar, ICRH on-axis heating resulted in higher core Ni impurity concentration in comparison to off-axis ICRH in L-mode. It was also found that the main core radiation during ICRH came from W.

  11. Reduced effect of impurities on the universal pairing scale in the cuprates 

    E-Print Network [OSTI]

    Vorontsov, A. B.; Abanov, Artem; Vavilov, M. G.; Chubukov, A. V.

    2010-01-01T23:59:59.000Z

    corrections are small numerically.22 The set of equations includes fermionic and bosonic self- energies in the normal state and the linearized equation for the d-wave pairing vertex #11;pf #12; #1; m#2; #1;Ref. 1#2; pf#1; m#2; = #5;T #1;#7; m#1; #8...; /2#5;T #1;#2;?#7;#1;1 /2#2;, where #7;#1;x#2; is the di-Gamma function and T 0 #1; is the pairing temperature in the absence of impurities #1;for an s-wave and magnetic impurities, the formula is the same,7 but with #3; /2 instead of #3...

  12. Ion thermal double layers in a pair-ion warm magnetized plasma containing charged dust impurities

    SciTech Connect (OSTI)

    El-Labany, S. K.; El-Shamy, E. F. [Department of Physics, Theoretical Physics Group, Faculty of Science, Mansoura University, Damietta El-Gedida 34517 (Egypt); El-Bedwehy, N. A. [Department of Mathematics, Faculty of Science, Mansoura University, Damietta El-Gedida 34517 (Egypt)

    2009-06-15T23:59:59.000Z

    In this paper the formation and the dynamics of ion thermal double layers (ITDLs) in a magnetized plasma, composed of positive and negative ions as well as a fraction of stationary charged (positive or negative) dust impurities have been studied. Using plasma hydrodynamics and Poisson equations for the two ion species, a modified Zakharov-Kuznetsov equation has been derived. The effects of the external magnetic field, the concentration of charged dust impurities, and the negative to positive ion temperature ratio on the ITDLs structure are investigated.

  13. Development of a particle injection system for impurity transport study in KSTAR

    SciTech Connect (OSTI)

    Lee, H. Y.; Hong, Joohwan; Lee, Seung Hun; Jang, Siwon; Jang, Juhyeok; Jeon, Taemin; Park, Jae Sun; Choe, Wonho, E-mail: wchoe@kaist.ac.kr [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea and Fusion Plasma Transport Research Center, Daejeon 305-701 (Korea, Republic of); Hong, Suk-Ho [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of)

    2014-11-15T23:59:59.000Z

    A solid particle injection system is developed for KSTAR. The system has a compact size, compatibility with a strong magnetic field and high vacuum environment, and the capability to inject a small amount of solid particles with a narrow injection angle. The target flight-distance of 10 cm has been achieved with a particle loss rate of less than 10%. Solid impurity particles such as tungsten and carbon will be injected by this system at the midplane in KSTAR. The impurity transport feature will be studied with a soft X-ray array, a vacuum ultra-violet diagnostic, and Stand Alone Non-Corona code.

  14. Reduced effect of impurities on the universal pairing scale in the cuprates

    E-Print Network [OSTI]

    Vorontsov, A. B.; Abanov, Artem; Vavilov, M. G.; Chubukov, A. V.

    2010-01-01T23:59:59.000Z

    corrections are small numerically.22 The set of equations includes fermionic and bosonic self- energies in the normal state and the linearized equation for the d-wave pairing vertex #11;pf #12; #1; m#2; #1;Ref. 1#2; pf#1; m#2; = #5;T #1;#7; m#1; #8...; /2#5;T #1;#2;?#7;#1;1 /2#2;, where #7;#1;x#2; is the di-Gamma function and T 0 #1; is the pairing temperature in the absence of impurities #1;for an s-wave and magnetic impurities, the formula is the same,7 but with #3; /2 instead of #3...

  15. Optical spectra and intensities of graphene magnetic dot bound to a negatively charged Coulomb impurity

    SciTech Connect (OSTI)

    Lee, C. M., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk; Chan, K. S., E-mail: mesimon-hk@yahoo.com.hk, E-mail: apkschan@cityu.edu.hk [Department of Physics and Materials Science and Center for Functional Photonics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Shenzhen Research Institute, City University of Hong Kong, Shenzhen (China)

    2014-07-28T23:59:59.000Z

    Employing numerical diagonalization, we study the optical properties of an electron in a monolayer-graphene magnetic dot bound to an off-center negatively charged Coulomb impurity based on the massless Dirac-Weyl model. Numerical results show that, since the electron-hole symmetry is broken by the Coulomb potential, the optical absorption spectra of the magnetic dot in the presence of a Coulomb impurity are different between the electron states and the hole states. Effects of both the magnetic field and the dot size on the absorption coefficient are presented as functions of the incident photon energies.

  16. Sodium and oxygen in Nigerian coals: Possible effects on ash fouling

    SciTech Connect (OSTI)

    Ewa, I.O.B.; Elegbe, S.B.; Adetunji, J. [Ahmadu Bello Univ., Zaria (Nigeria)

    1996-09-01T23:59:59.000Z

    Ash fouling during heat transfers in coal power-plants has been known to be an engineering problem caused by high sodium levels of the feed-coals. Instrumental Neutron Activation Analysis (INAA) was used in determining the concentration of some alkali elements (Na, Ca, Mg) associated with ash fouling for eight Nigerian coals mined at Onyeama, Ogbete, Enugu, Gombe, Okaba, Afikpo, Lafia and Asaba. Sodium levels were generally low (0.001-0.036%). Oxygen concentrations considered as an indicative measure of the wettability of each of the coals were determined. The possible effects of the concentration of these elements on ash fouling were discussed. 8 refs., 3 tabs.

  17. Normality: A Consistency Condition for Concurrent Objects

    E-Print Network [OSTI]

    Garg, Vijay

    Normality: A Consistency Condition for Concurrent Objects Vijay K. GARG \\Lambda Michel RAYNAL ECE for concurrent objects (objects shared by con­ current processes) that exploits the semantics of abstract data types. It provides the illusion that each operation applied by concurrent processes takes effect

  18. A Generalization of Generalized Arc Consistency

    E-Print Network [OSTI]

    Mackworth, Alan K.

    - binary classic constraint satisfaction problems (CSPs). Based on the Semiring CSP and Valued CSP such as fuzzy CSP, probabilistic CSP, max CSP, and weighted CSP. This extension is based on an idempotent satisfaction problem (CSP), local consistency can be char- acterized as deriving new constraints based on local

  19. Market Assessment and Demonstration of Lignite FBC Ash Flowable Fill Applications

    SciTech Connect (OSTI)

    Alan E. Bland

    2003-09-30T23:59:59.000Z

    Montana-Dakota Utilities (MDU) and Western Research Institute (WRI) have been developing flowable fill materials formulated using ash from the Montana-Dakota Utilities R. M. Heskett Station in Mandan, North Dakota. MDU and WRI have partnered with the U.S. Department of Energy (DOE) and the North Dakota Industrial Commission (NDIC) to further the development of these materials for lignite-fired fluidized-bed combustion (FBC) facilities. The MDU controlled density fill (CDF) appears to be a viable engineering material and environmentally safe. WRI is pursuing the commercialization of the technology under the trademark Ready-Fill{trademark}. The project objectives were to: (1) assess the market in the Bismarck-Mandan area; (2) evaluate the geotechnical properties and environmental compatibility; and (3) construct and monitor demonstrations of the various grades of flowable fill products in full-scale demonstrations. The scope of initial phase of work entailed the following: Task I--Assess Market for MDU Flowable Fill Products; Task II--Assess Geotechnical and Environmental Properties of MDU Flowable Fill Products; and Task III--Demonstrate and Monitor MDU Flowable Fill Products in Field-Scale Demonstrations. The results of these testing and demonstration activities proved the following: (1) The market assessment indicated that a market exists in the Bismarck-Mandan area for structural construction applications, such as sub-bases for residential and commercial businesses, and excavatable fill applications, such as gas line and utility trench filling. (2) The cost of the MDU flowable fill product must be lower than the current $35-$45/cubic yard price if it is to become a common construction material. Formulations using MDU ash and lower-cost sand alternatives offer that opportunity. An estimated market of 10,000 cubic yards of MDU flowable fill products could be realized if prices could be made competitive. (3) The geotechnical properties of the MDU ash-based flowable fill can be modified to meet the needs of a range of applications from structural fill applications to excavatable applications, such as utility trench fill. (4) Environmental assessments using standard testing indicate that the environmental properties of the fill materials are compatible with numerous construction applications and do not pose a threat to either adjacent groundwater or soils. (5) WRI developed an Environmental Field Simulator (EFS) method for assessing the impact of flowable fill materials on adjacent soils and found that the zone of impact is less than a couple of inches, thereby posing no threat to adjacent soils. (6) Field-scale demonstrations of the MDU flowable fill were constructed and were successful for structural, as well as excavatable applications. Monitoring has demonstrated the geotechnical performance, environmental performance, and compatibility with common embed materials with the MDU flowable fill products. Technical and economic issues were identified that may hinder the commercial acceptance of MDU flowable fill materials, including: (1) the ability to produce a consistent product; (2) the ability to provide a product year round (cold weather retards strength development); and (3) the ability to evaluate and produce commercial quantities of MDU flowable fill using inexpensive materials.

  20. Fluorocarbon impurities in KrF lasers Helen H. Hwang, Kristopher James, Roger Hui, and Mark J. KushneP)

    E-Print Network [OSTI]

    Kushner, Mark

    Fluorocarbon impurities in KrF lasers Helen H. Hwang, Kristopher James, Roger Hui, and Mark J, Urbana, Illinois 61801 (Received 24 January 1991; accepted for publication 7 March 1991) Fluorocarbon amounts of impurities, and flu- orocarbons in particular.' Fluorocarbons such as CF4 are common

  1. Methods for recovering a polar solvent from a fluid stream contaminated with at least one polar impurity

    DOE Patents [OSTI]

    Ginosar, Daniel M.; Wendt, Daniel S.

    2012-11-13T23:59:59.000Z

    A method of removing a polar solvent from a fluid volume contaminated with at least one polar impurity, such as a free fatty acid, is provided. The method comprises providing a fluid volume that includes at least one polar impurity dissolved in at least one solvent. The fluid volume is contacted with an expanding gas to remove the at least one solvent. The expanding gas may be dissolved into the at least one solvent in the fluid volume to form a gas-expanded solvent. The immiscibility of the polar impurities in the gas-expanded solvent enables separation of the polar impurities from the gas-expanded solvent. After separation of the polar impurities, at least one of the temperature and pressure may be reduced to separate the solvent from the expanding gas such that the clean solvent may be reused.

  2. Kinetics of fly ash beneficiation by carbon burnout. Quarterly report, October 1996--December 1996

    SciTech Connect (OSTI)

    Dodoo, J.N.; Okoh, J.M.; Diaz, A. [and others

    1997-06-01T23:59:59.000Z

    The presence of carbon in fly ash requires an increase in the dosage of the air-entraining admixture for concrete mix, and may cause the admixture to lose efficiency. Specifying authorities for the concrete producers have set maximum allowable levels of residual carbon. These levels are the so called {open_quotes}Loss On Ignition{close_quotes} (LOI). The concrete producer`s day-to-day purchasing decisions sets the LOI at 4%. The objective of the project is to investigate the kinetics of oxidation of residual carbon present in coal fly ash as a possible first step toward producing low-carbon fly ash from high-carbon, low quality fly ash.

  3. STATE-OF-THE-ART: FLY ASH, SILICA FUME AND SLAG UTILIZATION IN USA

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    improvement, land reclamations, slurried flowable ash, water pollution control, etc. The medium technology Backfill. 1.0 Introduction At the present time, coal fired electric power plants in the USA produce

  4. FLY ASH GENERATION AND UTILIZATION -AN OVERVIEW* Tarun R. Naik, Ph.D., P.E.

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    from conventional as well as advanced coal combustion technologies are addressed. Constructive use improvement, land reclamation, slurried flowable ash, and water pollution control. The medium technology matrix composites, polymer matrix composites, and several other filler applications. INTRODUCTION Coal

  5. PREDICTIONS FOR STRESS-STRAIN BEHAVIOR OF PANKI FLY-ASH USING MODIFIED CAM CLAY MODEL

    E-Print Network [OSTI]

    Prashant, Amit

    -ash is a fine powdery silty material, produced by burning of coal at thermal power plants. It shows specific by slurry disposal technique. A series of triaxial compression tests have been performed on overconsolidated

  6. ash forming acid-resistant: Topics by E-print Network

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

    Ash Dieback Update Date: Tuesday 26th March 2013 Time: 1400 - 1700hrs Location: Stirling Management Centre University of Stirling Stirling FK9 4LA To attend please return the...

  7. Iron distribution among phases in high- and low-sulfur coal fly ash

    SciTech Connect (OSTI)

    Hower, J.C.; Graham, U.M.; Rathbone, R.F. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Dyar, M.D.; Taylor, M.E. [West Chester Univ., PA (United States). Dept. of Geology and Astronomy

    1995-12-31T23:59:59.000Z

    Moessbauer spectroscopy, reflected-light optical microscopy, scanning-electron microscopy, wet chemical, and X-ray diffraction studies were conducted on six fly ash samples. The fly ashes, representing the combustion by-products of coals with total sulfur contents of less than 2% to greater than 4%, ranged from 17.6 to 32.0% Fe{sub 2}O{sub 3} by XRF analysis. Wet chemical analysis was used to determine the Fe{sup 3+}/{summation}Fe content of the ashes, which ranged from 72% to 83%. Optical analysis of the ashes indicated that the spinel, encompassing iron oxides of various compositions, ranges from 4.0 to 12.6% (vol.). Moessbauer analyses confirmed the presence of three Fe-bearing phases: magnetite, hematite (possibly of two different compositions), and glass. The variation in the Fe-oxidation state follows the variation in the sulfur, consequently pyrite, content of the feed coal.

  8. Notes on the efficacy of wet versus dry screening of fly ash

    SciTech Connect (OSTI)

    Valentim, B.; Hower, J.C.; Flores, D.; Guedes, A. [Center and Department of Geology, Oporto (Portugal)

    2008-08-15T23:59:59.000Z

    The methodology used to obtain fly ash subsamples of different sizes is generally based on wet or dry sieving methods. However, the worth of such methods is not certain if the methodology applied is not mentioned in the analytical procedure. After performing a fly ash mechanical dry, sieving, the authors compared those results with the ones obtained by laser diffraction on the same samples and found unacceptable discrepancies. A preliminary, study of a wet sieving analysis carried out on an economizer fly ash sample showed that this method was more effective than the dry sieving. The importance of standardizing the way samples are handled, pretreated and presented to the instrument of analysis are suggested and interlaboratory reproducibility trials are needed to create a common standard methodology to obtain large amounts of fly ash size fraction subsamples.

  9. Apparatus having inductively coupled coaxial coils for measuring buildup of slay or ash in a furnace

    DOE Patents [OSTI]

    Mathur, Mahendra P. (Pittsburgh, PA); Ekmann, James M. (Bethel Park, PA)

    1989-01-01T23:59:59.000Z

    The buildup of slag or ash on the interior surface of a furnace wall is monitored by disposing two coils to form a transformer which is secured adjacent to the inside surface of the furnace wall. The inductive coupling between the two coils of the transformer is affected by the presence of oxides of iron in the slag or ash which is adjacent to the transformer, and the application of a voltage to one winding produces a voltage at the other winding that is related to the thickness of the slag or ash buildup on the inside surface of the furnace wall. The output of the other winding is an electrical signal which can be used to control an alarm or the like or provide an indication of the thickness of the slag or ash buildup at a remote location.

  10. Lubricant-derived ash : in-engine sources and opportunities for reduction

    E-Print Network [OSTI]

    Watson, Simon A. G. (Simon Andrew Glean)

    2010-01-01T23:59:59.000Z

    Diesel particulate filters (DPF) are an effective means for meeting increasingly stringent emissions regulations that limit particulate matter. Over time, ash primarily derived from metallic additives in the engine oil ...

  11. Leaching of Metals from Fly ash-Amended Permeable Reactive Barriers Doina L. Morar 1

    E-Print Network [OSTI]

    Aydilek, Ahmet

    (Petzrick 2001). Unfortunately, this HCC fly ash cannot be beneficially reused in the construction industry organic and inorganic pollutants. Specific reactive materials such as wood chips, limestone, manure (USEPA

  12. Removal of radium from acidic solutions containing same by adsorption on coal fly ash

    DOE Patents [OSTI]

    Scheitlin, Frank M. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    The invention is a process for the removal of radium from acidic aqueous solutions. In one aspect, the invention is a process for removing radium from an inorganic-acid solution. The process comprises contacting the solution with coal fly ash to effect adsorption of the radium on the ash. The radium-containing ash then is separated from the solution. The process is simple, comparatively inexpensive, and efficient. High radium-distribution coefficients are obtained even at room temperature. Coal fly ash is an inexpensive, acid-resistant, high-surface-area material which is available in large quantities throughout the United States. The invention is applicable, for example, to the recovery of .sup.226 Ra from nitric acid solutions which have been used to leach radium from uranium-mill tailings.

  13. E-Print Network 3.0 - ash management regulations Sample Search...

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

    REGULATOR IN PORTLAND CEMENT 6 Traditionally about 3 to 5% gypsum is inter... of clean-coal ash (CCA) was used to replace gypsum as a setting time regulator and mineral...

  14. Review of WTE ash utilization processes under development in northwest Europe Athanasios Bourtsalas

    E-Print Network [OSTI]

    ferrous and non-ferrous, and also minerals from incinerator bottom ash (IBA). Also, since water systems for the discharged IBA has increased metal extraction efficiency and quality of residues

  15. aluminum-fly ash metal: Topics by E-print Network

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

    16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Journal of Composite Materials, July 2006, Vol. 40 no. 13, 1163-1174 1163 Thermal Expansion of AluminumFly Ash...

  16. Comparison of photosynthetic responses of Ashe juniper and live oak on the Edwards Plateau, Texas 

    E-Print Network [OSTI]

    Bendevis, Mira Arpe

    2009-06-02T23:59:59.000Z

    gas exchange and water relations at the leaf level of the two dominant tree species, Ashe juniper and live oak (Quercus virginiana P. Mill. Var. fusiformis), is important to assess the impact of juniper encroachment on the aquifer. Photosynthesis...

  17. Consistence beats causality in recommender systems

    E-Print Network [OSTI]

    Zhu, Xuzhen; Hu, Zheng; Zhang, Ping; Zhou, Tao

    2015-01-01T23:59:59.000Z

    The explosive growth of information challenges people's capability in finding out items fitting to their own interests. Recommender systems provide an efficient solution by automatically push possibly relevant items to users according to their past preferences. Recommendation algorithms usually embody the causality from what having been collected to what should be recommended. In this article, we argue that in many cases, a user's interests are stable, and thus the previous and future preferences are highly consistent. The temporal order of collections then does not necessarily imply a causality relationship. We further propose a consistence-based algorithm that outperforms the state-of-the-art recommendation algorithms in disparate real data sets, including \\textit{Netflix}, \\textit{MovieLens}, \\textit{Amazon} and \\textit{Rate Your Music}.

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

    E-Print Network [OSTI]

    Boyer, Edmond

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

  19. Effects of geometry and impurities on quantum rings in magnetic fields RID D-3014-2009

    E-Print Network [OSTI]

    Aichinger, M.; Chin, Siu A.; Krotscheck, E.; Rasanen, E.

    2006-01-01T23:59:59.000Z

    We investigate the effects of impurities and changing ring geometry on the energetics of quantum rings under different magnetic field strengths. We show that as the magnetic field and/or the electron number are/is increased, both the quasiperiodic...

  20. Low Velocity Boron Micro-Pellet Injector For Edge And Core Impurity Transport Measurements

    E-Print Network [OSTI]

    1 Low Velocity Boron Micro-Pellet Injector For Edge And Core Impurity Transport Measurements H. W, Baltimore, Maryland 21218 Abstract A simple Low Velocity Boron Micro-Pellet Injector has been under High velocity, pneumatic, pellet injection systems are applied routinely for injecting frozen pellets

  1. Effect of phosphorus impurity on tricalcium silicate T1: from synthesis to structural characterization

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Effect of phosphorus impurity on tricalcium silicate T1: from synthesis to structural: it is composed of tricalcium silicate Ca3SiO5 (C3S) modified in composition and crystal structure by ionic are calcium silicates: tricalcium silicate Ca3SiO5 (referred to as C3S) and dicalcium silicate Ca2SiO4

  2. Chemical binding energies of point defects in palladium doped with hydrogen and d impurities

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1001 Chemical binding energies of point defects in palladium doped with hydrogen and d impurities C calculate the chemical binding energy of a pair of hydrogen atoms in palladium within the infinite dilution] it is often assumed that the dominant contribution to the interaction energy between hydrogen atoms

  3. Impurity-defect interaction in polycrystalline silicon for photovoltaic applications. The role of hydrogen

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    655 Impurity-defect interaction in polycrystalline silicon for photovoltaic applications. The role of hydrogen A. Chari, P. de Mierry, A. Menikh and M. Aucouturier Laboratoire de Physique des Solides, C silicon, passivation of recombining defects by hydrogen, hydrogen-dopant interaction. A more focused

  4. EFFECT OF FUEL IMPURITY ON STRUCTURAL INTEGRITY OF Ni-YSZ ANODE OF SOFCs

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Marina, Olga A.; Pederson, Larry R.; Khaleel, Mohammad A.

    2011-01-01T23:59:59.000Z

    Electricity production through the integration of coal gasification with solid oxide fuel cells (SOFCs) may potentially be an efficient technique for clean energy generation. However, multiple minor and trace components are naturally present in coals. These impurities in coal gas not only degrade the electrochemical performance of Ni-YSZ anode used in SOFCs, but also severely endanger the structural integrity of the Ni-YSZ anode. In this paper, effect of the trace impurity of the coal syngases on the mechanical degradation of Ni-YSZ anode was studied by using an integrated experimental/modeling approach. Phosphorus is taken as an example of impurity. Anode-support button cell was used to experimentally explore the migration of phosphorous impurity in the Ni-YSZ anode of SOFCs. X-ray mapping was used to show elemental distributions and new phase formation. The subsequent finite element stress analyses were conducted using the actual microstructure of the anode to illustrate the degradation mechanism. It was found that volume expansion induced by the Ni phase change produces high stress level such that local failure of the Ni-YSZ anode is possible under the operating conditions

  5. Revealing the Degree of Magnetic Frustration by Non-Magnetic Impurities

    SciTech Connect (OSTI)

    Not Available

    2011-08-12T23:59:59.000Z

    Imaging the magnetic fields around a non-magnetic impurity can provide a clear benchmark for quantifying the degree of magnetic frustration. Focusing on the strongly frustrated J{sub 1}-J{sub 2} model and the spatially anisotropic J{sub 1a}-J{sub 1b}-J{sub 2} model, very distinct low energy behaviors reflect different levels of magnetic frustration. In the J{sub 1}-J{sub 2} model, bound magnons appear trapped near the impurity in the ground state and strongly reduce the ordered moments for sites proximal to the impurity. In contrast, local moments in the J{sub 1a}-J{sub 1b}-J{sub 2} model are enhanced on the impurity neighboring sites. These theoretical predictions can be probed by experiments such as nuclear magnetic resonance and scanning tunneling microscopy, and the results can elucidate the role of frustration in antiferromagnets and help narrow the possible models to understand magnetism in the iron pnictdies.

  6. IDENTIFYING IMPURITIES IN SURPLUS NON PIT PLUTONIUM FEEDS FOR MOX OR ALTERNATIVE DISPOSITION

    SciTech Connect (OSTI)

    Allender, J; Moore, E

    2010-07-14T23:59:59.000Z

    This report provides a technical basis for estimating the level of corrosion products in materials stored in DOE-STD-3013 containers based on extrapolating available chemical sample results. The primary focus is to estimate the levels of nickel, iron, and chromium impurities in plutonium-bearing materials identified for disposition in the United States Mixed Oxide fuel process.

  7. Engineering metal-impurity nanodefects for low-cost solar cells

    E-Print Network [OSTI]

    LETTERS Engineering metal-impurity nanodefects for low-cost solar cells TONIO BUONASSISI1 online: 14 August 2005; doi:10.1038/nmat1457 A s the demand for high-quality solar-cell feedstock exceeds in dramatic enhancements of performance even in heavily contaminated solar-cell material. Highly sensitive

  8. Effects of annealing and impurities on tensile properties of electrodeposited nanocrystalline Ni

    E-Print Network [OSTI]

    Wei, Qiuming

    growth 1. Introduction Electrodeposited nanocrystalline (nc) nickel has been used as a model materialEffects of annealing and impurities on tensile properties of electrodeposited nanocrystalline Ni Y form 13 August 2004; accepted 17 August 2004 Abstract The strength of electrodeposited nanocrystalline

  9. Impurity enrichment and radiative enhancement using induced SOL ow in DIII-D

    E-Print Network [OSTI]

    California at San Diego, University of

    Impurity enrichment and radiative enhancement using induced SOL ¯ow in DIII-D M.R. Wade *,1 , W on DIII-D have demonstrated the ecacy of using induced scrape-o-layer (SOL) ¯ow to preferentially enrich at the midplane and divertor exhaust. Using this SOL ¯ow, an improvement in enrichment (de®ned as the ratio of im

  10. Influence of age/size and grazing history on understory relationships of Ashe juniper

    E-Print Network [OSTI]

    Fuhlendorf, Samuel Dean

    1992-01-01T23:59:59.000Z

    INFLUENCE OF AGE/SIZE AND GRAZING HISTORY ON UNDERSTORY RELATIONSHIPS OF ASHE JUNIPER A Thesis by SAMUEL DEAN FUHLENDORF Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1992 Major Subject: Rangeland Ecology and Management INFLUENCE OF AGE/SIZE AND GRAZING HISTORY ON UNDERSTORY RELATIONSHIPS OF ASHE JUNIPER A Thesis by SAMUEL DEAN FUHLENDORF Approved as to style and content by...

  11. Investigation of the potential of fly ash as an adsorbent for removal of priority pollutants

    E-Print Network [OSTI]

    Zardkoohi, Minoo

    1993-01-01T23:59:59.000Z

    . Aydin Akgerman Adsorption isotherms for adsorption of phenol, p-chlorophenol, 2, 4, dichlorophenol, cadmium and lead from water onto fly ash were determined. These isotherms were modeled by the Freundlich isotherm. The value of Freundlich isotherm..., parameter n indicated that the adsorption isotherms for contaminants studied were unfavorable. Phenol displayed a much higher aAinity for fly ash than chlorophenol and 2, 4 dichlorophenol Adsorption isotherms for the trace metals studied were slightly...

  12. The use of sulfer modified bottom ash (SMBA) as an aggregate in asphaltic mixtures

    E-Print Network [OSTI]

    Chimakurthy, Harshavardhan

    1998-01-01T23:59:59.000Z

    , bottom ash is lighter in weight and generally much cheaper than conventional quality aggregates such as limestone, sand and gravel. This research was designed to up-grade the load-bearing charactcnstics of bottom ash and maximize its usc m asphaltic... and gravel. According to a study done by Hafizuddin Ahmad in 1974, sulfur was used extensively in sand-asphalt sulfur to upgrade marginal aggregates for use in asphaltic mixtures, was developed at Texas Transportation Institute (TT1) (JO). TTI's work...

  13. Technology for the Recovery of Fuel and Adsorbent Carbons from Coal Burning Utility Ash Ponds and Landfills

    SciTech Connect (OSTI)

    J.G. Groppo; T.L. Robl

    2005-09-30T23:59:59.000Z

    Several sampling techniques were evaluated to recover representative core samples from the ash ponds at Western Kentucky Energy's Coleman Station. The most successful was a combination of continuous-flight augers and specially designed soft-sediment sampling tubes driven by a Hammerhead drill mounted on an amphibious ARGO vehicle. A total of 51 core samples were recovered and analyzed in 3 ft sections and it was determined that there are 1,354,974 tons of ash in Pond C. Of the over 1.35M tons of ash present, 14% or 190K tons can be considered as coarse (+100 mesh). Pond C contains approximately 88K tons of carbon, nearly half of which is coarse and potentially recoverable with spiral concentration while the fine carbon (-100 mesh) is recoverable with froth flotation. There are 1.27M tons of carbon-free ash, 12% of which is coarse and potentially usable as block sand. Spiral concentration testing on bulk samples showed that product grade of 30 to 38% C (4200 to 5500 Btu/lb) was obtainable. When this product was cleaned again in an additional stage of spiral concentration, the product grade was improved to 7200 to 8200 Btu/lb with an accompanying 13 to 29% decrease in yield. Release analysis of hydraulically classified pond ash showed that froth flotation could provide froth products with as high a grade as 9000 Btu/lb with a yield of 5%. Increasing yield to 10% reduced froth grade to 7000 Btu/lb. Batch flotation provided froth grades as high as 6500 Btu/lb with yields of 7% with 1.5 lb/ton SPP and 1 lb/ton frother. Column flotation test results were similar to those achieved in batch flotation in terms of both grade and yield, however, carbon recoveries were lower (<70%). High airflow rate was required to achieve >50% carbon recovery and using wash water improved froth grade. Bottom ash samples were recovered from each of the units at Coleman Station. Characterization confirmed that sufficient quantity and quality of material is generated to produce a marketable lightweight aggregate and recover a high-grade fuel product. Spiral concentration provided acceptable grade lightweight aggregate with yields of only 10 to 20%. Incorporating a sieve bend into the process to recover coarse, porous ash particles from the outside race of the spirals increased aggregate yield to as high as 75%, however, the carbon content of the aggregate also increased. An opening size of 28 mesh on the sieve bend appeared to be sufficient. Lightweight concrete blocks (28 to 32 lbs) were produced from bottom ash and results show that acceptable strength could be attained with a cement/concrete ratio as low as 1/4. A mobile Proof-of-Concept (POC) field unit was designed and fabricated to meet the processing objectives of the project. The POC plant consisted of two trailer-mounted modules and was completely self sufficient with respect to power and water requirements. The POC unit was hauled to Coleman Station and operated at a feed rate of 2 tph. Results showed that the spirals operated similarly to previous pilot-scale operations and a 500 lb composite sample of coarse carbon was collected with a grade of 51.7% C or 7279 Btu/lb. Flotation results compared favorably with release analysis and 500 lbs of composite froth product was collected with a grade of 35% C or 4925 Btu/lb. The froth product was dewatered to 39% moisture with vacuum filtration. Pan pelletization and briquetting were evaluated as a means of minimizing handling concerns. Rotary pan pelletization produced uniform pellets with a compressive strength of 4 lbf without the use of any binder. Briquettes were produced by blending the coarse and fine carbon products at a ratio of 1:10, which is the proportion that the two products would be produced in a commercial operation. Using 3% lime as a binder produced the most desirable briquettes with respect to strength, attrition and drop testing. Additionally, the POC carbon products compared favorably with commercial activated carbon when used for removal of mercury from simulated flue gas. A business model was generated to summarize anti

  14. Investigation of fly ash carbon by thermal analysis and optical microscopy

    SciTech Connect (OSTI)

    Hill, R. [Boral Material Technologies Inc., San Antonio, TX (United States)] [Boral Material Technologies Inc., San Antonio, TX (United States); Rathbone, R.; Hower, J.C. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research] [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research

    1998-10-01T23:59:59.000Z

    A previous study investigated various fly ashes that had comparable loss on ignition values, but significant differences with respect to air entrainment performance. Thermal analysis data suggested that a poorly performing fly ash, with respect to air entrainment, contained a higher proportion of carbon that gasifies (oxidizes) at comparatively low temperatures. A relatively high abundance of isotropic carbon was identified in the poor-performing ash using optical microscopy. The present investigation examined a larger collection of fly ash samples to determine if thermal analysis could be used as a prognostic tool for fly ash performance. An attempt was made to correlate mortar air and foam index values for each sample with differential thermal analysis (DTA) data. Optical microscopy and BET surface area analysis were used as supportive techniques. No clear relationship could be established with the thermal or optical methods, although fly ash performance did correlate well with BET surface area. A low temperature component of the DTA exotherms was considered to be a function of inorganic catalytic species that reside on the carbon surface and lower the ignition temperature.

  15. Effect of temperature on the hydration of Portland cement blended with siliceous fly ash

    SciTech Connect (OSTI)

    Deschner, Florian, E-mail: florian.deschner@gmail.com [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Lothenbach, Barbara; Winnefeld, Frank [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Concrete and Construction Chemistry, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Neubauer, Jürgen [GeoZentrum Nordbayern, Mineralogy, University of Erlangen-Nuremberg, 91054 Erlangen (Germany)] [GeoZentrum Nordbayern, Mineralogy, University of Erlangen-Nuremberg, 91054 Erlangen (Germany)

    2013-10-15T23:59:59.000Z

    The effect of temperature on the hydration of Portland cement pastes blended with 50 wt.% of siliceous fly ash is investigated within a temperature range of 7 to 80 °C. The elevation of temperature accelerates both the hydration of OPC and fly ash. Due to the enhanced pozzolanic reaction of the fly ash, the change of the composition of the C–S–H and the pore solution towards lower Ca and higher Al and Si concentrations is shifted towards earlier hydration times. Above 50 °C, the reaction of fly ash also contributes to the formation of siliceous hydrogarnet. At 80 °C, ettringite and AFm are destabilised and the released sulphate is partially incorporated into the C–S–H. The observed changes of the phase assemblage in dependence of the temperature are confirmed by thermodynamic modelling. The increasingly heterogeneous microstructure at elevated temperatures shows an increased density of the C–S–H and a higher coarse porosity. -- Highlights: •The reaction of quartz powder at 80 °C strongly enhances the compressive strength. •Almost no strength increase of fly ash blended OPC at 80 °C was found after 2 days. •Siliceous hydrogarnet is formed upon the reaction of fly ash at high temperatures. •Temperature dependent change of the system was simulated by thermodynamic modelling. •Destabilisation of ettringite above 50 °C correlates with sulphate content of C–S–H.

  16. Selenium And Arsenic Speciation in Fly Ash From Full-Scale Coal-Burning Utility Plants

    SciTech Connect (OSTI)

    Huggins, F.E.; Senior, C.L.; Chu, P.; Ladwig, K.; Huffman, G.P.; /Kentucky U. /Reaction Engin. Int. /Elect. Power Res. Inst., Palo Alto

    2007-07-09T23:59:59.000Z

    X-ray absorption fine structure spectroscopy has been used to determine directly the oxidation states and speciation of selenium and arsenic in 10 fly ash samples collected from full-scale utility plants. Such information is needed to assess the health risk posed by these elements in fly ash and to understand their behavior during combustion and in fly ash disposal options, such as sequestration in tailings ponds. Selenium is found predominantly as Se(IV) in selenite (SeO{sub 3}{sup 2-}) species, whereas arsenic is found predominantly as As(V) in arsenate (AsO{sub 4}{sup 3-}) species. Two distinct types of selenite and arsenate spectra were observed depending upon whether the fly ash was derived from eastern U.S. bituminous (Fe-rich) coals or from western subbituminous or lignite (Ca-rich) coals. Similar spectral details were observed for both arsenic and selenium in the two different types of fly ash, suggesting that the post-combustion behavior and capture of both of these elements are likely controlled by the same dominant element or phase in each type of fly ash.

  17. The Laconia, New Hampshire bottom ash paving project: Volume 3, Physical Performance Testing Report

    SciTech Connect (OSTI)

    NONE

    1996-03-01T23:59:59.000Z

    Bottom ash is the principal waste stream from the combustion of municipal solid waste (MSW). It is comprised of grate ash (97%), the slag material discharged at the end of the grate system, and grate sifting (3%), the material that melts or falls through the grate structure. This project was conducted to demonstrate the feasibility of using municipal solid waste grate ash as an aggregate substitute in the construction of a pavement binder course for a portion of Rt. 3 in Laconia, New Hampshire. The research was conducted over a two year period during 1993 and 1994. This study is the culmination of an earlier two year characterization study between 1990 and 1992 that documented the physical and environmental characteristics of the bottom ash as it was produced at the Concord, N.H. waste-to-energy (@) facility and used in an asphaltic binder course. Together, these two studies provide a complete evaluation of the potential for using grate ash or bottom ash in asphalt binder course or as recycled asphalt pavement (RAP) in base courses in pavements.

  18. Encapsulation of mixed radioactive and hazardous waste contaminated incinerator ash in modified sulfur cement

    SciTech Connect (OSTI)

    Kalb, P.D.; Heiser, J.H. III; Colombo, P.

    1990-01-01T23:59:59.000Z

    Some of the process waste streams incinerated at various Department of Energy (DOE) facilities contain traces of both low-level radioactive (LLW) and hazardous constituents, thus yielding ash residues that are classified as mixed waste. Work is currently being performed at Brookhaven National Laboratory (BNL) to develop new and innovative materials for encapsulation of DOE mixed wastes including incinerator ash. One such material under investigation is modified sulfur cement, a thermoplastic developed by the US Bureau of Mines. Monolithic waste forms containing as much as 55 wt % incinerator fly ash from Idaho national Engineering Laboratory (INEL) have been formulated with modified sulfur cement, whereas maximum waste loading for this waste in hydraulic cement is 16 wt %. Compressive strength of these waste forms exceeded 27.6 MPa. Wet chemical and solid phase waste characterization analyses performed on this fly ash revealed high concentrations of soluble metal salts including Pb and Cd, identified by the Environmental Protection Agency (EPA) as toxic metals. Leach testing of the ash according to the EPA Toxicity Characteristic Leaching Procedure (TCLP) resulted in concentrations of Pb and Cd above allowable limits. Encapsulation of INEL fly ash in modified sulfur cement with a small quantity of sodium sulfide added to enhance retention of soluble metal salts reduced TCLP leachate concentrations of Pb and Cd well below EPA concentration criteria for delisting as a toxic hazardous waste. 12 refs., 4 figs., 2 tabs.

  19. EFFECTS OF FLY ASH ON MERCURY OXIDATION DURING POST COMBUSTION CONDITIONS

    SciTech Connect (OSTI)

    Glenn A. Norton

    1999-10-01T23:59:59.000Z

    Tests were performed in simulated flue gas streams using two fly ash samples from the electrostatic precipitators of two full-scale utility boilers. One fly ash was derived from a Powder River Basin (PRB) coal, while the other was derived from Blacksville coal (Pittsburgh No. 8 seam). The tests were performed at temperatures of 120 and 180 C under different gas compositions. Elemental mercury (Hg) streams were injected into the simulated flue gas and passed over filters (housed in a convection oven) loaded with fly ash. The Ontario Hydro method was used to determine the total amount of Hg passing through the filter as well as the percentages of elemental and oxidized Hg collected. Results indicated that substantial amounts of Hg oxidation did not occur with either fly ash, regardless of the temperature used for testing. When oxidation was observed, the magnitude of the oxidation was comparable between the two fly ashes. These results suggest that the gas matrix may be more important than the ash components with respect to the distribution of Hg species observed in gaseous effluents at coal-fired power plants.

  20. JOURNAL DE PHYSIQUE Colloque C5, supplkment au no 5, Tome 40, Mai 1979,page C5-40 High field magnetoresistanceof silver containing rare-earth impurities

    E-Print Network [OSTI]

    Boyer, Edmond

    and exchange scattering. 1. General. -Rare-earth impurities in metals give rise to an anisotropic magnetoresistanceof silver containing rare-earth impurities J. C. Ousset I.N.S.A., UniversitC Paul Sabatier, 31000 magnetoresistance dis- appears for Gd impurities (L = 0) and changes its sign half-way in the heavy rare-earth

  1. Self-consistent Gravitational Lens Reconstruction

    E-Print Network [OSTI]

    S. Dye; A. Taylor

    1998-08-13T23:59:59.000Z

    We present a new method for directly determining accurate, self-consistent cluster lens mass and shear maps in the strong lensing regime from the magnification bias of background galaxies. The method relies upon pixellisation of the surface mass density distribution which allows us to write down a simple, solvable set of equations. We also show how pixellisation can be applied to methods of mass determination from measurements of shear and present a simplified method of application. The method is demonstrated with cluster models and applied to magnification data from the lensing cluster Abell 1689.

  2. Self-consistent resonance in a plasma

    E-Print Network [OSTI]

    Evangelos Chaliasos

    2005-10-14T23:59:59.000Z

    As an application of the solution of the equations of electromagnetic self-consistency in a plasma, found in a previous paper, the study of controlled thermo-nuclear fusion is undertaken. This study utilizes the resonance which can be developed in the plasma, as indicated by the above solution, and is based to an analysis of the underlying forced oscillation under friction. As a consequence, we find that, in this way, controlled thermonuclear fusion seems now to be feasible in principle. The treatment is rather elementary, and it may serve as a guide for more detailed calculations.

  3. Consistency relations for the conformal mechanism

    SciTech Connect (OSTI)

    Creminelli, Paolo [Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34151, Trieste (Italy); Joyce, Austin; Khoury, Justin [Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Simonovi?, Marko, E-mail: creminel@ictp.it, E-mail: joyceau@sas.upenn.edu, E-mail: jkhoury@sas.upenn.edu, E-mail: marko.simonovic@sissa.it [SISSA, via Bonomea 265, 34136, Trieste (Italy)

    2013-04-01T23:59:59.000Z

    We systematically derive the consistency relations associated to the non-linearly realized symmetries of theories with spontaneously broken conformal symmetry but with a linearly-realized de Sitter subalgebra. These identities relate (N+1)-point correlation functions with a soft external Goldstone to N-point functions. These relations have direct implications for the recently proposed conformal mechanism for generating density perturbations in the early universe. We study the observational consequences, in particular a novel one-loop contribution to the four-point function, relevant for the stochastic scale-dependent bias and CMB ?-distortion.

  4. The consistency test on the cosmic evolution

    E-Print Network [OSTI]

    Gong, Yan; Zhang, Shuang-Nan; Chen, Xuelei

    2015-01-01T23:59:59.000Z

    We propose a new and robust method to test the consistency of the cosmic evolution given by a cosmological model. It is realized by comparing the combined quantity r_d^CMB/D_V^SN, which is derived from the comoving sound horizon r_d from cosmic microwave background (CMB) measurements and the effective distance D_V derived from low-redshift Type-Ia supernovae (SNe Ia) data, with direct and independent r_d/D_V obtained by baryon acoustic oscillation (BAO) measurements at median redshifts. We apply this test method for the LCDM and wCDM models, and investigate the consistency of the derived value of r_d/D_V from Planck 2015 and the SN Ia data sets of Union2.1 and JLA (z<1.5), and the r_d/D_V directly given by BAO data from six-degree-field galaxy survey (6dFGS), Sloan Digital Sky Survey Data Release 7 Main Galaxy Survey (SDSS-DR7 MGS), DR11 of SDSS-III, WiggleZ and Ly-alpha forecast surveys from Baryon Oscillation Spectroscopic Data (BOSS) DR-11 over 0.1

  5. Remedial Investigation Report on Chestnut Ridge Operable Unit 2 (Filled Coal Ash Pond/Upper McCoy Branch) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 1. Main Text

    SciTech Connect (OSTI)

    Not Available

    1994-08-01T23:59:59.000Z

    This document is a report on the remedial investigation (RI) of Chestnut Ridge Operable Unit (OU) 2 at the Oak Ridge Y-12 Plant. Chestnut Ridge OU 2 consists of Upper McCoy Branch (UMB), the Filled Coal Ash Pond (FCAP), and the area surrounding the Sluice Channel formerly associated with coal ash disposal in the FCAP. Chestnut Ridge OU 2 is located within the U.S. Department of Energy`s (DOE`s) Oak Ridge Reservation in Anderson County, Tennessee, approximately 24 miles west of Knoxville. The pond is an 8.5-acre area on the southern slope of Chestnut Ridge, 0.5 mile south of the main Y-12 Plant and geographically separated from the Y-12 Plant by Chestnut Ridge. The elevation of the FCAP is {approximately} 950 ft above mean sea level (msl), and it is relatively flat and largely vegetated. Two small ponds are usually present at the northeast and northwest comers of the FCAP. The Sluice Channel Area extends {approximately}1000 ft from the northern margin of the FCAP to the crest of Chestnut Ridge, which has an elevation of {approximately}1100 ft above msl. The Sluice Channel Area is largely vegetated also. McCoy Branch runs from the top of Chestnut Ridge across the FCAP into Rogers Quarry and out of the quarry where it runs a short distance into Milton Hill Lake at McCoy Embayment, termed UMB. The portion south of Rogers Quarry, within Chestnut Ridge OU 4, is termed Lower McCoy Branch. The DOE Oak Ridge Y-12 Plant disposed of coal ash from its steam plant operations as a slurry that was discharged into an ash retention impoundment; this impoundment is the FCAP. The FCAP was built in 1955 to serve as a settling basin after coal ash slurried over Chestnut Ridge from the Y-12 Plant. The FCAP was constructed by building an earthen dam across the northern tributary of McCoy Branch. The dam was designed to hold 20 years of Y-12 steam plant ash. By July 1967, ash had filled up the impoundment storage behind the dam to within 4 ft of the top.

  6. Models of neutron star atmospheres enriched with nuclear burning ashes

    E-Print Network [OSTI]

    Nättilä, Joonas; Kajava, Jari J E; Poutanen, Juri

    2015-01-01T23:59:59.000Z

    Low-mass X-ray binaries hosting neutron stars (NS) exhibit thermonuclear (type-I) X-ray bursts, which are powered by unstable nuclear burning of helium and/or hydrogen into heavier elements deep in the NS "ocean". In some cases the burning ashes may rise from the burning depths up to the NS photosphere by convection, leading to the appearance of the metal absorption edges in the spectra, which then force the emergent X-ray burst spectra to shift toward lower energies. These effects may have a substantial impact on the color correction factor $f_c$ and the dilution factor $w$, the parameters of the diluted blackbody model $F_E \\approx w B_E(f_c T_{eff})$ that is commonly used to describe the emergent spectra from NSs. The aim of this paper is to quantify how much the metal enrichment can change these factors. We have developed a new NS atmosphere modeling code, which has a few important improvements compared to our previous code required by inclusion of the metals. The opacities and the internal partition func...

  7. 488-4D ASH LANDFILL CLOSURE CAP HELP MODELING

    SciTech Connect (OSTI)

    Phifer, M.

    2014-11-17T23:59:59.000Z

    At the request of Area Completion Projects (ACP) in support of the 488-4D Landfill closure, the Savannah River National Laboratory (SRNL) has performed Hydrologic Evaluation of Landfill Performance (HELP) modeling of the planned 488-4D Ash Landfill closure cap to ensure that the South Carolina Department of Health and Environmental Control (SCDHEC) limit of no more than 12 inches of head on top of the barrier layer (saturated hydraulic conductivity of no more than 1.0E-05 cm/s) in association with a 25-year, 24-hour storm event is not projected to be exceeded. Based upon Weber 1998 a 25-year, 24-hour storm event at the Savannah River Site (SRS) is 6.1 inches. The results of the HELP modeling indicate that the greatest peak daily head on top of the barrier layer (i.e. geosynthetic clay liner (GCL) or high density polyethylene (HDPE) geomembrane) for any of the runs made was 0.079 inches associated with a peak daily precipitation of 6.16 inches. This is well below the SCDHEC limit of 12 inches.

  8. Hydration studies of calcium sulfoaluminate cements blended with fly ash

    SciTech Connect (OSTI)

    García-Maté, M.; De la Torre, A.G. [Departamento de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, 29071 Málaga (Spain)] [Departamento de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, 29071 Málaga (Spain); León-Reina, L. [Servicios Centrales de Apoyo a la Investigación, Universidad de Málaga, 29071 Málaga (Spain)] [Servicios Centrales de Apoyo a la Investigación, Universidad de Málaga, 29071 Málaga (Spain); Aranda, M.A.G. [Departamento de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, 29071 Málaga (Spain) [Departamento de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, 29071 Málaga (Spain); CELLS-Alba synchrotron, Carretera BP 1413, Km. 3.3, E-08290 Cerdanyola, Barcelona (Spain); Santacruz, I., E-mail: isantacruz@uma.es [Departamento de Química Inorgánica, Cristalografía y Mineralogía, Universidad de Málaga, 29071 Málaga (Spain)

    2013-12-15T23:59:59.000Z

    The main objective of this work is to study the hydration and properties of calcium sulfoaluminate cement pastes blended with fly ash (FA) and the corresponding mortars at different hydration ages. Laboratory X-ray powder diffraction, rheological studies, thermal analysis, porosimetry and compressive strength measurements were performed. The analysis of the diffraction data by Rietveld method allowed quantifying crystalline phases and overall amorphous contents. The studied parameters were: i) FA content, 0, 15 and 30 wt.%; and ii) water addition, water-to-CSA mass ratio (w/CSA = 0.50 and 0.65), and water-to-binder mass ratio (w/b = 0.50). Finally, compressive strengths after 6 months of 0 and 15 wt.% FA [w/CSA = 0.50] mortars were similar: 73 ± 2 and 72 ± 3 MPa, respectively. This is justified by the filler effect of the FA as no strong evidences of reactivity of FA with CSA were observed. These results support the partial substitution of CSA cements with FA with the economic and environmental benefits.

  9. Characteristics of fly ashes from full-scale coal-fired power plants and their relationship to mercury adsorption

    SciTech Connect (OSTI)

    Yongqi Lu; Massoud Rostam-Abadi; Ramsay Chang; Carl Richardson; Jennifer Paradis [Illinois State Geological Survey, Champaign, IL (United States)

    2007-08-15T23:59:59.000Z

    Nine fly ash samples were collected from the particulate collection devices of four full-scale pulverized coal utility boilers burning eastern bituminous coals and three cyclone utility boilers burning either Powder River Basin coals or PRB blends. As-received fly ash samples were mechanically sieved to obtain six size fractions. Unburned carbon content, mercury content, and Brunauer-Emmett-Teller surface areas of as-received fly ashes and their size fractions were measured. In addition, UBC particles were examined by scanning electron microscopy, high-resolution transmission microscopy, and thermogravimetry to obtain information on their surface morphology, structure, and oxidation reactivity. It was found that the UBC particles contained amorphous carbon, ribbon-shaped graphitic carbon, and highly ordered graphite structures. The mercury contents of the UBCs in raw ash samples were comparable to those of the UBC-enriched samples, indicating that mercury was mainly adsorbed on the UBC in fly ash. The UBC content decreased with a decreasing particle size range for all nine ashes. The mercury content of the UBCs in each size fraction, however, generally increased with a decreasing particle size for the nine ashes. The mercury contents and surface areas of the UBCs in the PRB-CYC ashes were about 8 and 3 times higher than UBCs in the EB-PC ashes, respectively. It appeared that both the particle size and surface area of UBC could contribute to mercury capture. The particle size of the UBC in PRB-CYC ash and thus the external mass transfer was found to be the major factor impacting the mercury adsorption. Both the particle size and surface reactivity of the UBC in EB-PC ash, which generally had a lower carbon oxidation reactivity than the PRB-PC ashes, appeared to be important for the mercury adsorption. 26 refs., 16 figs., 2 tabs.

  10. Trophic structure and metal bioaccumulation differences in multiple fish species exposed to coal ash-associated metals

    SciTech Connect (OSTI)

    Otter, Ryan [Middle Tennessee State University; Bailey, Frank [Middle Tennessee State University; Fortner, Allison M [ORNL; Adams, Marshall [ORNL

    2012-01-01T23:59:59.000Z

    On December 22, 2008 a dike containing coal fly ash from the Tennessee Valley Authority Kingston Fossil Plant near Kingston Tennessee USA failed and resulted in the largest coal ash spill in U.S. history. Coal ash, the by-product of coal combustion, is known to contain multiple contaminants of concern, including arsenic and selenium. The purpose of this study was to investigate the bioaccumulation of arsenic and selenium and to identify possible differences in trophic dynamics in feral fish at various sites in the vicinity of the Kingston coal ash spill. Elevated levels of arsenic and selenium were observed in various tissues of largemouth bass, white crappie, bluegill and redear sunfish from sites associated with the Kingston coal ash spill. Highest concentrations of selenium were found in redear sunfish with liver concentrations as high as 24.83 mg/kg dry weight and ovary concentrations up to 10.40 mg/kg dry weight at coal ash-associated sites. To help explain the elevated selenium levels observed in redear sunfish, investigations into the gut pH and trophic dynamics of redear sunfish and bluegill were conducted which demonstrated a large difference in the gut physiology between these two species. Redear sunfish stomach and intestinal pH was found to be 1.1 and 0.16 pH units higher than in bluegill, respectively. In addition, fish from coal ash-associated sites showed enrichment of 15N & 13C compared to no ash sites, indicating differences in food web dynamics between sites. These results imply the incorporation of coal ash-associated compounds into local food webs and/or a shift in diet at ash sites compared to the no ash reference sites. Based on these results, further investigation into a broader food web at ash-associated sites is warranted.

  11. Reliability and Consistency of Surface Contamination Measurements

    SciTech Connect (OSTI)

    Rouppert, F.; Rivoallan, A.; Largeron, C.

    2002-02-26T23:59:59.000Z

    Surface contamination evaluation is a tough problem since it is difficult to isolate the radiations emitted by the surface, especially in a highly irradiating atmosphere. In that case the only possibility is to evaluate smearable (removeable) contamination since ex-situ countings are possible. Unfortunately, according to our experience at CEA, these values are not consistent and thus non relevant. In this study, we show, using in-situ Fourier Transform Infra Red spectrometry on contaminated metal samples, that fixed contamination seems to be chemisorbed and removeable contamination seems to be physisorbed. The distribution between fixed and removeable contamination appears to be variable. Chemical equilibria and reversible ion exchange mechanisms are involved and are closely linked to environmental conditions such as humidity and temperature. Measurements of smearable contamination only give an indication of the state of these equilibria between fixed and removeable contamination at the time and in the environmental conditions the measurements were made.

  12. Self-consistent bounces in two dimensions

    SciTech Connect (OSTI)

    Baacke, Juergen; Kevlishvili, Nina [Institut fuer Physik, Universitaet Dortmund, D-44221 Dortmund (Germany)

    2005-01-15T23:59:59.000Z

    We compute bounce solutions describing false vacuum decay in a {phi}{sup 4} model in two dimensions in the Hartree approximation, thus going beyond the usual one-loop corrections to the decay rate. We use zero energy mode functions of the fluctuation operator for the numerical computation of the functional determinant and the Green's function. We thus avoid the necessity of discretizing the spectrum, as it is necessary when one uses numerical techniques based on eigenfunctions. Regularization is performed in analogy of standard perturbation theory; the renormalization of the Hartree approximation is based on the two-particle point-irreducible scheme. The iteration towards the self-consistent solution is found to converge for some range of the parameters. Within this range we find the corrections to the leading one-loop approximation to be relatively small, not exceeding 1 order of magnitude in the total transition rate.

  13. Interdiffusion and impurity diffusion in polycrystalline Mg solid solution with Al or Zn

    SciTech Connect (OSTI)

    Kammerer, Catherine [University of Central Florida, Orlando; Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Sohn, Yong Ho [University of Central Florida

    2014-01-01T23:59:59.000Z

    Interdiffusion and impurity diffusion in Mg binary solid solutions, Mg(Al) and Mg(Zn) were investigated at temperatures ranging from 623 to 723 K. Interdiffusion coef cients were determined via the Boltzmann Matano Method using solid-to-solid diffusion couples assembled with polycrystalline Mg and Mg(Al) or Mg(Zn) solid solutions. In addition, the Hall method was employed to extrapolate the impurity diffusion coef cients of Al and Zn in pure polycrystalline Mg. For all diffusion couples, electron micro-probe analysis was utilized for the measurement of concentration pro les. The interdiffusion coef cient in Mg(Zn) was higher than that of Mg(Al) by an order of magnitude. Additionally, the interdiffusion coef cient increased signi cantly as a function of Al content in Mg(Al) solid solution, but very little with Zn content in Mg(Zn) solid solution. The activation energy and pre-exponential factor for the average effective interdiffusion coef cient in Mg(Al) solid solution were determined to be 186.8 ( 0.9) kJ/mol and 7.69 x 10-1 ( 1.80 x 10-1) m2/s, respectively, while those determined for Mg(Zn) solid solution were 139.5 ( 4.0) kJ/mol and 1.48 x 10-3 ( 1.13 x 10-3) m2/s. In Mg, the Zn impurity diffusion coef cient was an order of magnitude higher than the Al impurity diffusion coef cient. The activation energy and pre-exponential factor for diffusion of Al impurity in Mg were determined to be 139.3 ( 14.8) kJ/mol and 6.25 x 10-5 ( 5.37 x 10-4) m2/s, respectively, while those for diffusion of Zn impurity in Mg were determined to be 118.6 ( 6.3) kJ/mol and 2.90 x 10-5 ( 4.41 x 10-5) m2/s.

  14. Predicting the Operating Behavior of Ceramic Filters from Thermo-Mechanical Ash Properties

    SciTech Connect (OSTI)

    Hemmer, G.; Kasper, G.

    2002-09-19T23:59:59.000Z

    Stable operation, in other words the achievement of a succession of uniform filtration cycles of reasonable length is a key issue in high-temperature gas filtration with ceramic media. Its importance has rather grown in recent years, as these media gain in acceptance due to their excellent particle retention capabilities. Ash properties have been known for some time to affect the maximum operating temperature of filters. However, softening and consequently ''stickiness'' of the ash particles generally depend on composition in a complex way. Simple and accurate prediction of critical temperature ranges from ash analysis--and even more so from coal analysis--is still difficult without practical and costly trials. In general, our understanding of what exactly happens during break-down of filtration stability is still rather crude and general. Early work was based on the concept that ash particles begin to soften and sinter near the melting temperatures of low-melting, often alkaline components. This softening coincides with a fairly abrupt increase of stickiness, that can be detected with powder mechanical methods in a Jenicke shear cell as first shown by Pilz (1996) and recently confirmed by others (Kamiya et al. 2001 and 2002, Kanaoka et al. 2001). However, recording {sigma}-{tau}-diagrams is very time consuming and not the only off-line method of analyzing or predicting changes in thermo-mechanical ash behavior. Pilz found that the increase in ash stickiness near melting was accompanied by shrinkage attributed to sintering. Recent work at the University of Karlsruhe has expanded the use of such thermo-analytical methods for predicting filtration behavior (Hemmer 2001). Demonstrating their effectiveness is one objective of this paper. Finally, our intent is to show that ash softening at near melting temperatures is apparently not the only phenomenon causing problems with filtration, although its impact is certainly the ''final catastrophe''. There are other significant changes in regeneration at intermediate temperatures, which may lead to long-term deterioration.

  15. On-line carbon-in-ash monitors: Survey and demonstration

    SciTech Connect (OSTI)

    Sorge, J.; Larrimore, L.

    1998-02-01T23:59:59.000Z

    Fly ash unburned carbon (UBC) level is an important consideration for combustion efficiency as well as ash marketing. The presence of unburned carbon in fly ash has been shown to be a function of furnace design, coal quality, the ability of the pulverizer to grind the coal, and heat release rate. Boilers are designed to take these factors into consideration. However, the Clean Air Act Amendments of 1990 drove many utilities to switch coal supplies and install low NO{sub x} burners. Higher carbon-in-ash levels have been the result of these changes in coal quality and the staged combustion characteristics associated with low NO{sub x} burners. Over the past few years, several instruments for the on-line determination and monitoring of the unburned carbon content of ash samples have been developed. However, to date they have not been deployed widely in the U.S. despite potential uses for combustion optimization and as an aid in fly ash marketing. Based on the lack of publicly available performance and operation data available for the current CIAM (carbon-in-ash monitor) commercial offerings, Southern Company initiated a demonstration of several commercial technologies on its coal-fired units. As part of a DOE Clean Coal Project demonstrating advanced wall-fired combustion techniques for the reduction on NO{sub x} emissions from coal-fired boilers, the CAM, SEKAM and FOCUS systems were installed at Georgia Power Company`s Plant Hammond Unit 4. CAM and M&W instruments were also placed at Alabama Power Company`s Plant Gaston Unit 4. The testing of the instruments was conducted from November 1995 through August 1996.

  16. Electrostatic potential variation on the flux surface and its impact on impurity transport

    E-Print Network [OSTI]

    García-Regaña, J M; Turkin, Y; Kleiber, R; Helander, P; Maaßberg, H; Alonso, J A; Velasco, J L

    2015-01-01T23:59:59.000Z

    The particle transport of impurities in magnetically confined plasmas under some conditions does not find, neither quantitatively nor qualitatively, a satisfactory theory-based explanation. This compromise the successful realization of thermo-nuclear fusion for energy production since its accumulation is known to be one of the causes that leads to the plasma breakdown. In standard reactor-relevant conditions this accumulation is in most stellarators intrinsic to the lack of toroidal symmetry, that leads to the neoclassical electric field to point radially inwards. This statement, that the standard theory allows to formulate, has been contradicted by some experiments that showed weaker or no accumulation under such conditions \\cite{Ida_pop_16_056111_2009, Yoshinuma_nf_49_062002_2009}. The charge state of the impurities makes its transport more sensitive to the electric fields. Thus, the short length scale turbulent electrostatic potential or its long wave-length variation on the flux surface $\\Phi_{1}$ -- that...

  17. Evidence of impurity assisted tunneling in SiGe/Si heterostructures

    SciTech Connect (OSTI)

    Zhukavin, R. Kh.; Bekin, N. A.; Lobanov, D. N.; Drozdov, M. N.; Drozdov, Yu. N.; Kozlov, D. V.; Pryakhin, D. A.; Shastin, V. N. [Institute for Physics of Microstructures RAS, 603950, Nizhny Novgorod, GSP-105 (Russian Federation); Shengurov, V. G. [Nizhny Novgorod State University, 603950, Nizhny Novgorod, Gagarina avenue, 23 (Russian Federation)

    2013-12-04T23:59:59.000Z

    The investigation of vertical transport in delta-doped SiGe/Si heterostructures has been presented. The asymmetrical triple barrier structure was grown by MBE technique. The delta layer of boron impurity was placed into the center of narrower quantum well. The growth procedure was followed by conventional processing including photolithography and plasma etching and magnetron sputtering. SIMS and X-rays diagnostics have been used to control the desired structure. The conductance of the structure has been measured at liquid helium temperature and analyzed. All pronounced resonances have been identified. The resonant feature near 60 mV has to be attributed to impurity-assisted tunneling that is supported by calculation of binding energy of the acceptor in the narrower quantum well.

  18. Coal Fly Ash as a Source of Iron in Atmospheric Dust

    SciTech Connect (OSTI)

    Chen, Haihan; Laskin, Alexander; Baltrusaitis, Jonas; Gorski, Christopher A.; Scherer, Michelle; Grassian, Vicki H.

    2012-01-18T23:59:59.000Z

    Anthropogenic coal fly ash aerosols may represent a significant source of bioavailable iron in the open ocean. Few measurements have been made to compare the solubility of atmospheric iron from anthropogenic aerosols and other sources. We report an investigation of the iron dissolution of three fly ash samples in acidic aqueous solutions and compare the solubilities with that of Arizona test dust, a reference material of mineral dust. The effects of pH, cloud processing, and solar irradiation on Fe solubility were explored. Similar to previously reported results on mineral dust, iron in aluminosilicate phases provide predominant dissolved iron compared with iron in oxides. Iron solubility of fly ash is higher than Arizona test dust, especially at the higher pH conditions investigated. Simulated atmospheric processing elevates iron solubility due to significant changes in the morphology aluminosilicate glass, a dominantly material in fly ash particle. Iron continuously releases into the aqueous solution as fly ash particles break up into smaller fragments. The assessment of dissolved atmospheric iron deposition fluxes, and their effect on the biogeochemistry at ocean surface should be constrained by taking into account the source, environment pH, Fe speciation, and solar radiation.

  19. Investigation of MSWI fly ash melting characteristic by DSC-DTA

    SciTech Connect (OSTI)

    Li, Rundong [Institute of Clean Energy and Environmental Engineering, Liaoning Key Laboratory of Clean Energy, Shenyang Institute of Aeronautical Engineering, Shenyang 110136 (China)], E-mail: leerd@mail.tsinghua.edu.cn; Wang, Lei; Yang, Tianhua; Raninger, Bernhard [Institute of Clean Energy and Environmental Engineering, Liaoning Key Laboratory of Clean Energy, Shenyang Institute of Aeronautical Engineering, Shenyang 110136 (China)

    2007-07-01T23:59:59.000Z

    The melting process of MSWI (Municipal Solid Waste Incineration) fly ash has been studied by high-temperature DSC-DTA experiments. The experiments were performed at a temperature range of 20-1450 deg. C, and the considerable variables included atmosphere (O{sub 2} and N{sub 2}), heating rates (5 deg. C/min, 10 deg. C/min, 20 deg. C/min) and CaO addition. Three main transitions were observed during the melting process of fly ash: dehydration, polymorphic transition and fusion, occurring in the temperature range of 100-200 deg. C, 480-670 deg. C and 1101-1244 deg. C, respectively. The apparent heat capacity and heat requirement for melting of MSWI fly ash were obtained by DSC (Differential Scanning Calorimeter). A thermodynamic modeling to predict the heat requirements for melting process has been presented, and it agrees well with the experimental data. Finally, a zero-order kinetic model of fly ash melting transition was established. The apparent activation energy of MSWI fly ash melting transition was obtained.

  20. Sorption of cadmium and lead by clays from municipal incinerator ash-water suspensions

    SciTech Connect (OSTI)

    Roy, W.R.; Krapac, I.G.; Steele, J.D. [Illinois State Geological Survey, Champaign, IL (United States)

    1993-07-01T23:59:59.000Z

    The effect of Cl complexation in extracts of a flue gas-scrubber incinerator fly ash sample on the sorption of Cd and Ph by kaolinite and illite was investigated using batch-sorption methods. In the pH range of 5 to 9, Cl complexation may reduce sorption and thus increase the mobility of these metals. When an ash-water suspension was acidified to pH 6.85, the dissolution of Cl and Ca essentially eliminated Cd sorption because of complexation and cationic competition. Cadmium would be considered as either mobile or very mobile under these conditions. Lead was not soluble in the pH-6.85 suspension. At pH 12, the approximate pH of water in contact with flue gas-scrubber fly ash, Cd was essentially insoluble and Ph occurred as anionic Ph hydroxide. Anionic Ph was sorbed by the two clays, and the extent of sorption was not influenced by Cl or carbonate complexation. Sorption constants, derived from isotherms, suggested that Ph would be relatively immobile in saturated soil-water systems. The recent concern that highly alkaline, flue gas-scrubber fly ash may release environmentally significant concentrations of mobile Ph when placed in an ash-disposal site with a soil liner should be reevaluated in light of this study. 37 refs., 6 figs., 3 tabs.

  1. Progress on Problem about Quantum Hamming Bound for Impure Quantum Codes

    E-Print Network [OSTI]

    Zhuo Li; Lijuan Xing

    2009-07-22T23:59:59.000Z

    A famous open problem in the theory of quantum error-correcting codes is whether or not the parameters of an impure quantum code can violate the quantum Hamming bound for pure quantum codes. We partially solve this problem. We demonstrate that there exists a threshold such that an arbitrary quantum code must obey the quantum Hamming bound whenever . We list some values of for small d and binary quantum codes.

  2. Interaction of impurity ions with a weakly non-Maxwellian simple hydrogenic plasma

    SciTech Connect (OSTI)

    Terry, W.K.

    1988-08-01T23:59:59.000Z

    The average acceleration of an ensemble of ''test particles'' in a plasma is called the ''dynamical friction''; the average rate at which their velocity vectors spread out in velocity space is expressed in a velocity-space diffusion-rate tensor. These quantities are derived for impurity ions interacting with a weakly non-Maxwellian simple hydrogenic plasma. The distribution functions for the plasma ions and electrons are written explicitly. 5 refs., 3 figs.

  3. Impurity-induced disorder in III-nitride materials and devices

    DOE Patents [OSTI]

    Wierer, Jr., Jonathan J; Allerman, Andrew A

    2014-11-25T23:59:59.000Z

    A method for impurity-induced disordering in III-nitride materials comprises growing a III-nitride heterostructure at a growth temperature and doping the heterostructure layers with a dopant during or after the growth of the heterostructure and post-growth annealing of the heterostructure. The post-growth annealing temperature can be sufficiently high to induce disorder of the heterostructure layer interfaces.

  4. Fourier spectroscopy of individual nitrogen impurity centers in GaAs

    SciTech Connect (OSTI)

    Ikezawa, Michio [PRESTO-JST, JST, Kawaguchi, Japan and Institute of Physics, University of Tsukuba, Tsukuba (Japan); Zhang, Liao; Mori, Tatsuya; Masumoto, Yasuaki [Institute of Physics, University of Tsukuba, Tsukuba (Japan); Sakuma, Yoshiki; Sakoda, Kazuaki [National Institute for Materials Science, Tsukuba (Japan)

    2013-12-04T23:59:59.000Z

    We report on the measurement of the exciton homogeneous linewidth in nitrogen impurity centers in GaAs:N. Fourier spectroscopy on a single center revealed a long coherence time over 300 ps at low temperature. The narrowest linewidth obtained at liquid helium temperature is 3.5 ?eV, which is comparable with that of semiconductor quantum dots. The linewidth increases with increasing temperature, showing a thermally activated behavior with activation energies of 2?5 meV.

  5. Method for removal of plutonium impurity from americium oxides and fluorides

    DOE Patents [OSTI]

    FitzPatrick, J.R.; Dunn, J.G.; Avens, L.R.

    1987-02-13T23:59:59.000Z

    Method for removal of plutonium impurity from americium oxides and fluorides. AmF/sub 4/ is not further oxidized to AmF/sub 6/ by the application of O/sub 2/F at room temperature thereto, while plutonium compounds present in the americium sample are fluorinated to volatile PuF/sub 6/, which can readily be separated therefrom, leaving the purified americium oxides and/or fluorides as the solid tetrafluoride thereof.

  6. Method for removal of plutonium impurity from americium oxides and fluorides

    DOE Patents [OSTI]

    FitzPatrick, John R. (Los Alamos, NM); Dunn, Jerry G. (Los Alamos, NM); Avens, Larry R. (Los Alamos, NM)

    1987-01-01T23:59:59.000Z

    Method for removal of plutonium impurity from americium oxides and fluorides. AmF.sub.4 is not further oxidized to AmF.sub.6 by the application of O.sub.2 F at room temperature, while plutonium compounds present in the americium sample are fluorinated to volatile PuF.sub.6, which can readily be separated therefrom, leaving the purified americium oxides and/or fluorides as the solid tetrafluoride.

  7. Effect of flue gas impurities on the process of injection and storage of carbon dioxide in depleted gas reservoirs

    E-Print Network [OSTI]

    Nogueira de Mago, Marjorie Carolina

    2005-11-01T23:59:59.000Z

    sequestration. In this thesis, I report my findings on the effect of flue gas ??impurities?? on the displacement of natural gas during CO2 sequestration, and results on unconfined compressive strength (UCS) tests to carbonate samples. In displacement experiments...

  8. Fly ash-enhanced aluminum composites for automotive parts. [Reports for April to June, 1998, and July to September, 1998

    SciTech Connect (OSTI)

    Golden, Dean; Rohatgi, Pradeep

    1998-10-15T23:59:59.000Z

    The objectives of this report are to produce and evaluate the use of aluminum ''ashalloys''--metal matrix composites that incorporate coal fly ash--in the commercial manufacture of cast automotive parts. Some highlights are: (1) Ashalloy ingot with ''C'' type fly ash was synthesized using stir casting techniques similar to the successful castings of ''F'' type fly ash. Agglomeration was noted. Stirring periods were increased up to 45 minutes compared to the normal 5 minutes to determine whether the shear force of stirring would disagglomerate the clusters noted with this type of fly ash. The resulting sample showed clustering. (2) The ashalloy ingots of ''C'' type fly ash were remelted and poured into permanent molds using a cloth filter to screen out clusters. There was no major reduction in clusters of fly ash particles in the composite since the filter with the mesh size larger than 1 x 1 mm was used. The composite melt would not flow through when filters with smaller openings were used. (3) The fly ash sample from Wisconsin Electric Power Company was sent for classification. (4) A 1 lb. sample of JTM-processed fly ash was sent to Wisconsin Electric Power Company for classification and 10 lb. of same fly ash was sent to The Jet Pulverizer Company for jet milling. (5) Experiments on fly ash pretreatment as well as synthesis of ash alloy are continuing. (6) Attempts are being made to apply high speed shear mixing with selected liquids to disperse the clusters noted in ashalloy with the ''C'' type fly ash base. Stir casting processes have been developed to incorporate type ''F'' fly ash of different sizes and measuring tensile data on cast bars. This data enables selection of the optimum size of fly ash to meet specific property requirements. Attempts are underway to develop stir casting techniques to incorporate ''C'' type fly ash in cast aluminum alloys. It is expected that the next milestone for making trial parts will be completed on schedule by June 1999.

  9. Suppression of fine ash formation in pulverized coal flames. Final technical report, September 30, 1992--January 31, 1996

    SciTech Connect (OSTI)

    Kramlich, J.C.; Chenevert, B.; Park, Jungsung; Hoffman, D.A.; Butcher, E.K.

    1996-07-19T23:59:59.000Z

    Coal ash, and particularly fine fly ash, remain one of the principal practical and environmental problems in coal-based power generation. In particular, submicron aerosols are identified with direct inhalation risk. Submicron ash is thought to arise from mineral vaporization during char combustion, followed by nucleation, condensation and coagulation to yield an aerosol. While aerosols are predominantly made out of volatile alkali minerals, they also can include refractory oxides that are chemically reduced to more volatile forms within the char particle and vaporized. Most of the ash of size greater than 1 {mu}m is generated by agglomeration of mineral as the char particle bums out. These two principal mechanisms are thought to account for most of the ash generated in coal combustion. Previous research has shown that various forms of coal treatment can influence the yields of fine ash from combustion. The research reported here investigates various forms of treatment, including physical coal cleaning, aerodynamic sizing, degree of grinding, and combinations of these on both aerosol yields and on yields of fine residual ash (1-4 {mu}m). The work also includes results from the combustion of artificial chars that include individual mineral elements. This research shows that these various forms of coal treatment can significantly change ash characteristics. While none of the treatments affected the bulk of the residual ash size distribution significantly, the yield of the ash aerosol mode (d<0.5 {mu}m) and fine residual ash mode (1-4 {mu}m) are changed by the treatments.

  10. Numerical Realization of a Shell Model for Impurity Spreading in Plasmas

    SciTech Connect (OSTI)

    Tokar, M. Z.; Koltunov, M. [Institute for Energy and Climate Research-Plasma Physics, Research Center Juelich GmbH, Juelich, 52428 (Germany)

    2011-09-14T23:59:59.000Z

    In plasmas of fusion devices impurity particles are released as a consequence of wall erosion and are seeded deliberately for diverse purposes. Often they enter the plasma volume from small spots and spread away both along and perpendicular to the magnetic field. This process is described by continuity, motion and heat balance equations taking into account such physical processes as ionization by electrons, friction and heating in coulomb collisions with background ions, etc. In present paper we introduce a shell model where solutions of these equations, such as the densities of different impurity ions, are approximated by functions decaying exponentially from the source region due to the ionization into higher charged states. By integrating the original transport equations over several space regions, we get a set of ordinary differential equations describing the time evolution of the characteristic values for the impurity ion densities, fluxes, temperatures, and the dimensions along and across the magnetic field of the clouds where different states are predominantly localized. The equations obtained include time derivatives of complex non-linear combinations of the variables in question. Two numerical approaches to solve such equations are elaborated and compared by considering the spreading of lithium particles in deuterium plasma.

  11. Thermoelectric properties of two-dimensional topological insulators doped with nonmagnetic impurities

    SciTech Connect (OSTI)

    Li, L. L., E-mail: lllihfcas@foxmail.com [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Xu, W., E-mail: wenxu-issp@aliyun.com [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Department of Physics, Yunnan University, Kunming 650091 (China)

    2014-07-07T23:59:59.000Z

    We present a theoretical study on the thermoelectric properties of two-dimensional topological insulators (2DTIs) doped with nonmagnetic impurities. We develop a tractable model to calculate the electronic band structure without additional input parameters and to evaluate the thermoelectric properties of 2DTIs based on CdTe/HgTe quantum wells. We find that with increasing the doping concentration of nonmagnetic impurity, the edge states dominate the thermoelectric transport and the bulk-state conduction is largely suppressed. For typical sample parameters, the thermoelectric figure of merit ZT (a quantity used to characterize the conversion efficiency of a thermoelectric device between the heat and electricity) can be much larger than 1, which is a great advance over conventional thermoelectric materials. Furthermore, we show that with decreasing the 2DTI ribbon width or the Hall-bar width, ZT can be considerably further improved. These results indicate that the CdTe/HgTe 2DTIs doped with nonmagnetic impurities can be potentially applied as high-efficiency thermoelectric materials and devices.

  12. Runaway electrons as a source of impurity and reduced fusion yield in the dense plasma focus

    SciTech Connect (OSTI)

    Lerner, Eric J.; Yousefi, Hamid R. [LPPFusion, Inc., 128 Lincoln Blvd., Middlesex, New Jersey 08846 (United States)

    2014-10-15T23:59:59.000Z

    Impurities produced by the vaporization of metals in the electrodes may be a major cause of reduced fusion yields in high-current dense plasma focus devices. We propose here that a major, but hitherto-overlooked, cause of such impurities is vaporization by runaway electrons during the breakdown process at the beginning of the current pulse. This process is sufficient to account for the large amount of erosion observed in many dense plasma focus devices on the anode very near to the insulator. The erosion is expected to become worse with lower pressures, typical of machines with large electrode radii, and would explain the plateauing of fusion yield observed in such machines at higher peak currents. Such runaway electron vaporization can be eliminated by the proper choice of electrode material, by reducing electrode radii and thus increasing fill gas pressure, or by using pre-ionization to eliminate the large fields that create runaway electrons. If these steps are combined with monolithic electrodes to eliminate arcing erosion, large reductions in impurities and large increases in fusion yield may be obtained, as the I{sup 4} scaling is extended to higher currents.

  13. Neutron flux estimations based on niobium impurities in reactor pressure vessel steel

    SciTech Connect (OSTI)

    Baers, L.B.; Hasanen, E.K. [Technical Research Centre of Finland, Espoo (Finland). Reactor Lab.

    1994-12-31T23:59:59.000Z

    The use of (ppm level) niobium impurities in reactor pressure vessel (RPV) steel for neutron flux estimations based on the reaction {sup 93}Nb (n,n{prime}) {sup 93m}Nb has been reported previously. The method has now been further investigated and refined. Small niobium fractions in RPV steel ({approx} ppm) and plating ({approx} 1%) materials have been separated by ion exchange chromatography in one to three steps. The measured Nb fractions in samples from some four pressure vessel (RPV) base materials were 1 to 3 ppm. The purification of tens of milligrams of RPV material provides sufficient amounts of niobium for mass determination with a highly sensitive (10{sup {minus}5} ppm) Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The {sup 93m}Nb and small remaining {sup 54}Mn activities were measured with a Calibrated Liquid Scintillation Counter (LSC) based on dual label technique and almost 100% efficiency to {sup 93m}Nb. One purification is needed for plating materials ({approx}1% Nb) and two purifications of about one gram of steel with Nb impurities in order to resolve the needed activities ({approx}10 Bq {sup 93m}Nb/{mu}g Nb). The achieved accuracy of the measured specific {sup 93m}Nb activities was about {+-} 3% (1{sigma}) in irradiated RPV plating materials and about {+-} 4% for Nb ppm impurities.

  14. Analyzing the Radiation Properties of High-Z Impurities in High-Temperature Plasmas

    SciTech Connect (OSTI)

    Reinke, M. L.; Ince-Cushman, A.; Podpaly, Y.; Rice, J. E. [Plasma Science and Fusion Center, Cambridge, MA (United States); Bitter, M.; Hill, K. W. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Fournier, K. B. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Gu, M. F. [Space Science Laboratory, Berkeley, CA (United States)

    2009-09-10T23:59:59.000Z

    Most tokamak-based reactor concepts require the use of noble gases to form either a radiative mantle or divertor to reduce conductive heat exhaust to tolerable levels for plasma facing components. Predicting the power loss necessary from impurity radiation is done using electron temperature-dependent 'cooling-curves' derived from ab initio atomic physics models. We present here a technique to verify such modeling using highly radiative, argon infused discharges on Alcator C-Mod. A novel x-ray crystal imaging spectrometer is used to measure spatially resolved profiles of line-emissivity, constraining impurity transport simulations. Experimental data from soft x-ray diodes, bare AXUV diodes and foil bolometers are used to determine the local emissivity in three overlapping spectral bands, which are quantitatively compared to models. Comparison of broadband measurements show agreement between experiment and modeling in the core, but not over the entire profile, with the differences likely due to errors in the assumed radial impurity transport outside of the core. Comparison of Ar{sup 16+} x-ray line emission modeling to measurements suggests an additional problem with the collisional-radiative modeling of that charge state.

  15. Baseline risk assessment of ground water contamination at the inactive uriniferous lignite ashing site near Belfield, North Dakota

    SciTech Connect (OSTI)

    NONE

    1994-08-01T23:59:59.000Z

    This Baseline Risk Assessment of Ground Water Contamination at the Inactive Uraniferous Lignite Ashing Site Near Belfield, North Dakota, evaluates potential impacts to public health or the environment resulting from ground water contamination at the site where coal containing uranium was burned to produce uranium. The US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project is evaluating plans to remedy soil and ground water contamination at the site. Phase I of the UMTRA Project consists of determining the extent of soil contamination. Phase II of the UMTRA Project consists of evaluating ground water contamination. Under Phase II, results of this risk assessment will help determine what remedial actions may be necessary for contaminated ground water at the site. This risk assessment evaluates the potential risks to human health and the environment resulting from exposure to contaminated ground water as it relates to historic processing activities at the site. Potential risk is quantified for constituents introduced from the processing activities, and not for those constituents naturally occurring in water quality in the site vicinity. Background ground water quality has the potential to cause adverse health effects from exposure through drinking. Any risks associated with contaminants attributable to site activities are incremental to these risks from background ground water quality. This incremental risk from site-related contaminants is quantified in this risk assessment. The baseline risk from background water quality is incorporated only into the assessment of potential chemical interactions and the definition of the overall site condition.

  16. Inclusion property of Cs, Sr, and Ba impurities in LiCl crystal formed by layer-melt crystallization

    SciTech Connect (OSTI)

    Choi, Jung-Hoon; Cho, Yung-Zun; Lee, Tae-Kyo; Eun, Hee-Chul; Kim, Jun-Hong; Park, Hwan-Seo; Kim, In-Tae; Park, Geun-Il [Nuclear Fuel Cycle Waste Treatment Research Division, Korea Atomic Energy Research Institute, Daejeon, 305-353 (Korea, Republic of)

    2013-07-01T23:59:59.000Z

    Pyroprocessing is one of the promising technologies enabling the recycling of spent nuclear fuels from a commercial light water reactor (LWR). In general, pyroprocessing uses dry molten salts as electrolytes. In particular, LiCl waste salt after pyroprocessing contains highly radioactive I/II group fission products mainly composed of Cs, Sr, and Ba impurities. Therefore, it is beneficial to reuse LiCl salt in the pyroprocessing as an electrolyte for economic and environmental issues. Herein, to understand the inclusion property of impurities within LiCl crystal, the physical properties such as lattice parameter change, bulk modulus, and substitution enthalpy of a LiCl crystal having 0-6 at% Cs{sup +} or Ba{sup 2+} impurities under existence of 1 at% Sr{sup 2+} impurity were calculated via the first-principles density functional theory. The substitution enthalpy of LiCl crystals having 1 at% Sr{sup 2+} showed slightly decreased value than those without Sr{sup 2+} impurity. Therefore, through the substitution enthalpy calculation, it is expected that impurities will be incorporated within LiCl crystal as co-existed form rather than as a single component form. (authors)

  17. Ash plume properties retrieved from infrared images: a forward and inverse modeling approach

    E-Print Network [OSTI]

    Cerminara, Matteo; Valade, Sébastien; Harris, Andrew J L

    2014-01-01T23:59:59.000Z

    We present a coupled fluid-dynamic and electromagnetic model for volcanic ash plumes. In a forward approach, the model is able to simulate the plume dynamics from prescribed input flow conditions and generate the corresponding synthetic thermal infrared (TIR) image, allowing a comparison with field-based observations. An inversion procedure is then developed to retrieve ash plume properties from TIR images. The adopted fluid-dynamic model is based on a one-dimensional, stationary description of a self-similar (top-hat) turbulent plume, for which an asymptotic analytical solution is obtained. The electromagnetic emission/absorption model is based on the Schwarzschild's equation and on Mie's theory for disperse particles, assuming that particles are coarser than the radiation wavelength and neglecting scattering. [...] Application of the inversion procedure to an ash plume at Santiaguito volcano (Guatemala) has allowed us to retrieve the main plume input parameters, namely the initial radius $b_0$, velocity $U_...

  18. Leaching and toxicity behavior of coal-biomass waste cocombustion ashes

    SciTech Connect (OSTI)

    Skodras, G.; Prokopidou, M.; Sakellaropoulos, G.P. [Aristotle University in Thessaloniki, Thessaloniki (Greece). Dept. for Chemical Engineering

    2006-08-15T23:59:59.000Z

    Land disposal of ash residues, obtained from the cocombustion of Greek lignite with biomass wastes, is known to create problems due to the harmful constituents present. In this regard, the leachability of trace elements from lignite, biomass, and blends cocombustion ashes was investigated by using the Toxicity Characteristic Leaching Procedure (TCLP) of the US Environmental Protection Agency (US EPA). In this work, the toxicity of the aqueous leachates and the concentrations of the metals obtained from the leaching procedure were measured using the Microtox test (Vibrio fischen) and inductive coupled plasma-atomic emission spectrometer (ICP-AES), respectively. The toxic effects of most leachates on Vibrio fischeri were found to be significantly low in both 45% and 82% screening test protocols. However, the liquid sample originating from olive kernels fly ash (FA4) caused the highest toxic effect in both protocols, which can be attributed to its relatively high concentrations of As, Cd, Co, Cu, Mn, Ni, and Zn.

  19. ASHE PDC: The Quality and Patient Safety Movement Posted on: 3.15.2011 11:50:52 AM Posted by Jennifer Kovacs, Managing Editor

    E-Print Network [OSTI]

    Vaziri, Ashkan

    ASHE PDC: The Quality and Patient Safety Movement Posted on: 3.15.2011 11:50:52 AM Posted for Patient Care and Hospital Facilities?" at the ASHE PDC Summit in Tampa, Florida. Benneyan is director

  20. Feasibility of using reject fly ash in cement-based stabilization/solidification processes

    SciTech Connect (OSTI)

    Poon, C.S.; Qiao, X.C.; Cheeseman, C.R.; Lin, Z.S. [Hong Kong Polytechnic University, Kowloon (China). Dept. of Civil & Structural Engineering

    2006-01-15T23:59:59.000Z

    Stabilization/solidification (s/s) has been routinely used for the final treatment of hazardous wastes prior to land disposal. These processes involve adding one or more solidifying reagents into the waste to transform it into a monolithic solid with improved structural integrity. Cement-based systems with partial replacement by pulverized fuel ash (PFA) have been widely used to minimize leaching of contaminants from hazardous wastes. The finer fraction of PFA ({lt}45 {mu} m, fine fly ash, MA), produced by passing the raw ash through a classifying process is commonly used in s/s processes. Low-grade fly ash is rejected (rFA) from the ash classifying process, and is largely unused due to high carbon content and large particle size but represents a significant proportion of PFA. This paper presents experimental results of a study that has assessed the feasibility of using rFA in the cement-based s/s of a synthetic heavy metal waste. Results were compared to mixes containing fFA. The strength results show that cement-based waste forms with rFA replacement are suitable for disposal at landfill and that the addition of heavy metal sludge can increase the degree of hydration of fly ash and decrease the porosity of samples. Adding Ca(OH){sub 2} and flue gas desulphurization sludge reduces the retarding effect of heavy metals on strength development. The results of the Toxicity Characteristic Leaching Procedure and Dynamic Leach Test show that rFA can be used in cement-based s/s wastes without compromising performance of the product.

  1. Computation of probabilistic hazard maps and source parameter estimation for volcanic ash transport and dispersion

    SciTech Connect (OSTI)

    Madankan, R. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Pouget, S. [Department of Geology, University at Buffalo (United States); Singla, P., E-mail: psingla@buffalo.edu [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Bursik, M. [Department of Geology, University at Buffalo (United States); Dehn, J. [Geophysical Institute, University of Alaska, Fairbanks (United States); Jones, M. [Center for Computational Research, University at Buffalo (United States); Patra, A. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Pavolonis, M. [NOAA-NESDIS, Center for Satellite Applications and Research (United States); Pitman, E.B. [Department of Mathematics, University at Buffalo (United States); Singh, T. [Department of Mechanical and Aerospace Engineering, University at Buffalo (United States); Webley, P. [Geophysical Institute, University of Alaska, Fairbanks (United States)

    2014-08-15T23:59:59.000Z

    Volcanic ash advisory centers are charged with forecasting the movement of volcanic ash plumes, for aviation, health and safety preparation. Deterministic mathematical equations model the advection and dispersion of these plumes. However initial plume conditions – height, profile of particle location, volcanic vent parameters – are known only approximately at best, and other features of the governing system such as the windfield are stochastic. These uncertainties make forecasting plume motion difficult. As a result of these uncertainties, ash advisories based on a deterministic approach tend to be conservative, and many times over/under estimate the extent of a plume. This paper presents an end-to-end framework for generating a probabilistic approach to ash plume forecasting. This framework uses an ensemble of solutions, guided by Conjugate Unscented Transform (CUT) method for evaluating expectation integrals. This ensemble is used to construct a polynomial chaos expansion that can be sampled cheaply, to provide a probabilistic model forecast. The CUT method is then combined with a minimum variance condition, to provide a full posterior pdf of the uncertain source parameters, based on observed satellite imagery. The April 2010 eruption of the Eyjafjallajökull volcano in Iceland is employed as a test example. The puff advection/dispersion model is used to hindcast the motion of the ash plume through time, concentrating on the period 14–16 April 2010. Variability in the height and particle loading of that eruption is introduced through a volcano column model called bent. Output uncertainty due to the assumed uncertain input parameter probability distributions, and a probabilistic spatial-temporal estimate of ash presence are computed.

  2. Heavy metal leaching from coal fly ash amended container substrates during Syngonium production

    SciTech Connect (OSTI)

    Li, Q.S.; Chen, J.J.; Li, Y.C. [University of Florida, Apopka, FL (United States)

    2008-02-15T23:59:59.000Z

    Coal fly ash has been proposed to be an alternative to lime amendment and a nutrient source of container substrates for ornamental plant production. A great concern over this proposed beneficial use, however, is the potential contamination of surface and ground water by heavy metals. In this study, three fly ashes collected from Florida, Michigan, and North Carolina and a commercial dolomite were amended in a basal substrate. The formulated substrates were used to produce Syngonium podophyllum Schott 'Berry Allusion' in 15-cm diameter containers in a shaded greenhouse. Leachates from the containers were collected during the entire six months of plant production and analyzed for heavy metal concentrations. There were no detectable As, Cr, Hg, Pb, and Se in the leachates; Cd and Mo were only detected in few leachate samples. The metals constantly detected were Cu, Mn, Ni, and Zn. The total amounts of Cu, Mn, Ni, and Zn leached during the six-month production period were 95, 210, 44, and 337 {mu} g per container, indicating that such amounts in leachates may contribute little to contamination of surface and ground water. In addition, plant growth indices and fresh and dry weights of S. podophyllum 'Berry Allusion' produced from fly ash and dolomite-amended substrates were comparable except for the plants produced from the substrate amended with fly ash collected from Michigan which had reduced growth indices and fresh and dry weights. Thus, selected fly ashes can be alternatives to commercial dolomites as amendments to container substrates for ornamental plant production. The use of fly ashes as container substrate amendments should represent a new market for the beneficial use of this coal combustion byproduct.

  3. Sulfur capture by oil shale ashes under atmospheric and pressurized FBC conditions

    SciTech Connect (OSTI)

    Yrjas, K.P.; Hupa, M. [Aabo Akademi Univ., Turku (Finland). Dept. of Chemical Engineering; Kuelaots, I.; Ots, A. [Tallinn Technical Univ. (Estonia). Thermal Engineering Dept.

    1995-12-31T23:59:59.000Z

    When oil shale contains large quantities of limestone, a significant auto-absorption of sulfur is possible under suitable conditions. The sulfur capture by oil shale ashes has been studied using a pressurized thermogravimetric apparatus. The chosen experimental conditions were typical for atmospheric and pressurized fluidized bed combustion. The Ca/S molar ratios in the two oil shales studied were 8 (Estonian) and 10 (Israeli). The samples were first burned in a gas atmosphere containing O{sub 2} and N{sub 2} (and CO{sub 2} if pressurized). After the combustion step, SO{sub 2} was added and sulfation started. The results with the oil shales were compared to those obtained with an oil shale cyclone ash from the Narva power plant in Estonia. In general, the results from the sulfur capture experiments under both atmospheric and pressurized conditions showed that the oil shale cannot only capture its own sulfur but also significant amounts of additional sulfur of another fuel if the fuels are mixed together. For example from the runs at atmospheric pressure, the conversion of CaO to CaSO{sub 4} was about 70% for Israeli oil shale and about 55% for Estonian oil shale (850 C). For the cyclone ash the corresponding conversion was about 20%. In comparison it could be mentioned that under the same conditions the conversions of natural limestones are about 30%. The reason the cyclone ash was a poor sulfur absorbent was probably due to its temperature history. In Narva the oil shale was burned at a significantly higher temperature (1,400 C) than was used in the experiments (750 C and 850 C). This caused the ash to sinter and the reactive surface area of the cyclone ash was therefore decreased.

  4. Development of Fly Ash Derived Sorbents to Capture CO2 from Flue Gas of Power Plants

    SciTech Connect (OSTI)

    M. Mercedes Maroto-Valer; John M. Andresen; Yinzhi Zhang; Zhe Lu

    2003-12-31T23:59:59.000Z

    This research program focused on the development of fly ash derived sorbents to capture CO{sub 2} from power plant flue gas emissions. The fly ash derived sorbents developed represent an affordable alternative to existing methods using specialized activated carbons and molecular sieves, that tend to be very expensive and hinder the viability of the CO{sub 2} sorption process due to economic constraints. Under Task 1 'Procurement and characterization of a suite of fly ashes', 10 fly ash samples, named FAS-1 to -10, were collected from different combustors with different feedstocks, including bituminous coal, PRB coal and biomass. These samples presented a wide range of LOI value from 0.66-84.0%, and different burn-off profiles. The samples also spanned a wide range of total specific surface area and pore volume. These variations reflect the difference in the feedstock, types of combustors, collection hopper, and the beneficiation technologies the different fly ashes underwent. Under Task 2 'Preparation of fly ash derived sorbents', the fly ash samples were activated by steam. Nitrogen adsorption isotherms were used to characterize the resultant activated samples. The cost-saving one-step activation process applied was successfully used to increase the surface area and pore volume of all the fly ash samples. The activated samples present very different surface areas and pore volumes due to the range in physical and chemical properties of their precursors. Furthermore, one activated fly ash sample, FAS-4, was loaded with amine-containing chemicals (MEA, DEA, AMP, and MDEA). The impregnation significantly decreased the surface area and pore volume of the parent activated fly ash sample. Under Task 3 'Capture of CO{sub 2} by fly ash derived sorbents', sample FAS-10 and its deashed counterpart before and after impregnation of chemical PEI were used for the CO{sub 2} adsorption at different temperatures. The sample FAS-10 exhibited a CO{sub 2} adsorption capacity of 17.5mg/g at 30 C, and decreases to 10.25mg/g at 75 C, while those for de-ashed counterpart are 43.5mg/g and 22.0 mg/g at 30 C and 75 C, respectively. After loading PEI, the CO{sub 2} adsorption capacity increased to 93.6 mg/g at 75 C for de-ashed sample and 62.1 mg/g at 75 C for raw fly ash sample. The activated fly ash, FAS-4, and its chemical loaded counterparts were tested for CO{sub 2} capture capacity. The activated carbon exhibited a CO{sub 2} adsorption capacity of 40.3mg/g at 30 C that decreased to 18.5mg/g at 70 C and 7.7mg/g at 120 C. The CO{sub 2} adsorption capacity profiles changed significantly after impregnation. For the MEA loaded sample the capacity increased to 68.6mg/g at 30 C. The loading of MDEA and DEA initially decreased the CO{sub 2} adsorption capacity at 30 C compared to the parent sample but increased to 40.6 and 37.1mg/g, respectively, when the temperature increased to 70 C. The loading of AMP decrease the CO{sub 2} adsorption capacity compared to the parent sample under all the studied temperatures. Under Task 4 'Comparison of the CO{sub 2} capture by fly ash derived sorbents with commercial sorbents', the CO{sub 2} adsorption capacities of selected activated fly ash carbons were compared to commercial activated carbons. The CO{sub 2} adsorption capacity of fly ash derived activated carbon, FAS-4, and its chemical loaded counterpart presented CO{sub 2} capture capacities close to 7 wt%, which are comparable to, and even better than, the published values of 3-4%.

  5. Comparative analysis of methods for determination of arsenic in coal and coal ash

    SciTech Connect (OSTI)

    Vukasinovic-Pesic, V.L.; Blagojevic, N.Z.; Rajakovic, L.V. [University of Montenegro, Podgorica (Montenegro)

    2009-07-01T23:59:59.000Z

    In this paper the comparative analysis of different methods for the preparation and analysis of arsenic content in coal and coal ash have been presented. The suggested method is coal digestion method, i.e., coal ash digestion using the mixture of acids: nitric and sulphuric in presence of vanadium-pentoxide as catalyzer. The comparative analysis of different recording techniques (AAS-GH, AAS-GF and ICP-AES) has also been presented. For arsenic recording the suggested technique is AAS-GF technique. The obtained results show that the method of high precision, high sensitivity and high reproductivity has been obtained.

  6. Evaluation of lime-fly ash stabilized bases and subgrades using static and dynamic deflection systems 

    E-Print Network [OSTI]

    Raba, Gary W.

    1982-01-01T23:59:59.000Z

    structural evaluations of the subgrade and its overlying pavement layers for test sites in Texas. Six evaluations of the lime-fly ash stabilization technique, based on dual parametric results, are given in this thesis. ACKNOWLEDGMENTS The author wishes... FOR TEST SITE 5 H. DFFLECTION MEASUREMENTS FOR TEST SITE 8 VITA PAGE 141 141 154 160 160 172 181 181 195 202 213 213 213 215 220 227 231 238 245 252 259 268 275 LIST OF TABLES TABLE PAGE 10. 12. 13. 14. Lime-Fly Ash...

  7. Silicon materials task of the low cost solar array project (Phase III). Effect of impurities and processing on silicon solar cells. Phase III summary and seventeenth quarterly report, Volume 1: characterization methods for impurities in silicon and impurity effects data base

    SciTech Connect (OSTI)

    Hopkins, R.H.; Davis, J.R.; Rohatgi, A.; Campbell, R.B.; Blais, P.D.; Rai-Choudhury, P.; Stapleton, R.E.; Mollenkopf, H.C.; McCormick, J.R.

    1980-01-01T23:59:59.000Z

    The object of Phase III of the program has been to investigate the effects of various processes, metal contaminants and contaminant-process interactions on the performance of terrestrial silicon solar cells. The study encompassed a variety of tasks including: (1) a detailed examination of thermal processing effects, such as HCl and POCl/sub 3/ gettering on impurity behavior, (2) completion of the data base and modeling for impurities in n-base silicon, (3) extension of the data base on p-type material to include elements likely to be introduced during the production, refining, or crystal growth of silicon, (4) effects on cell performance on anisotropic impurity distributions in large CZ crystals and silicon webs, and (5) a preliminary assessment of the permanence of the impurity effects. Two major topics are treated: methods to measure and evaluate impurity effects in silicon and comprehensive tabulations of data derived during the study. For example, discussions of deep level spectroscopy, detailed dark I-V measurements, recombination lifetime determination, scanned laser photo-response, and conventional solar cell I-V techniques, as well as descriptions of silicon chemical analysis are included. Considerable data are tabulated on the composition, electrical, and solar cell characteristics of impurity-doped silicon.

  8. Intra- and inter-unit variation in fly ash petrography: Examples from a western Kentucky power station

    SciTech Connect (OSTI)

    Hower, J.C.; Rathbone, R.F. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Goodman, J. [Prestonburg High School, KY (United States)

    1998-12-31T23:59:59.000Z

    Fly ash was collected from eight mechanical and ten baghouse hoppers at each of twin 150-MW wall-fired units in a western Kentucky power station. The fuel burned at that time was a blend of low-sulfur, high volatile bituminous Central Appalachian coals. The baghouse ash showed less variation between units than the mechanical units. The coarser mechanical fly ash showed significant differences in the amount of total carbon and in the ratio of isotropic coke to both total carbons and total coke; the latter excluding inertinite and other unburned, uncoked coal. There was no significant variation in ratios of inorganic fly ash constituents. The inter-unit differences in the amount and forms of mechanical fly ash carbon appear to be related to differences in pulverizer efficiency, leading to greater amounts of coarse coal, therefore unburned carbon, in one of the units.

  9. Demineralization of petroleum cokes and fly ash samples obtained from the upgrading of Athabasca oil sands bitumen

    SciTech Connect (OSTI)

    Majid, A.; Ratcliffe, C.I.; Ripmeester, J.A. (National Research Council of Canada, Ottawa, ON (Canada). Div. of Chemistry)

    1989-01-01T23:59:59.000Z

    Ash reduction of the cokes and fly ash samples derived from the Athabasca oil sands bitumen was attempted by dissolving the mineral matter in acids. The samples used for this investigation included Syncrude fluid coking coke, Suncor delayed coking coke and the two fly ash samples obtained from the combustion of these cokes. All samples were analyzed for C,H,N,O, and S before and after acid demineralization and the analyses results compared. Further, the ash from the samples before and after acid demineralization was analyzed for silica, alumina, iron titanium, nickel and vanadium to assess the acid leaching of these elements. CP/MAS, /sup 13/C NMR spectroscopic study of the demineralized coke and fly ash samples was also attempted.

  10. Conversion of Fly Ash into Mesoporous Aluminosilicate Hsiao-Lan Chang, Chang-Min Chun, Ilhan A. Aksay, and Wei-Heng Shih*,

    E-Print Network [OSTI]

    Aksay, Ilhan A.

    and aluminum sources. Fly ash, which is a byproduct of coal burning, contains mostly aluminosilicates. Recently not only eliminates the disposal problem of fly ash but also turns an otherwise waste materialConversion of Fly Ash into Mesoporous Aluminosilicate Hsiao-Lan Chang, Chang-Min Chun, Ilhan A

  11. Final Technical Report: Effects of Impurities on Fuel Cell Performance and Durability

    SciTech Connect (OSTI)

    James G. Goodwin, Jr.; Hector Colon-Mercado; Kitiya Hongsirikarn; and Jack Z. Zhang

    2011-11-11T23:59:59.000Z

    The main objectives of this project were to investigate the effect of a series of potential impurities on fuel cell operation and on the particular components of the fuel cell MEA, to propose (where possible) mechanism(s) by which these impurities affected fuel cell performance, and to suggest strategies for minimizing these impurity effects. The negative effect on Pt/C was to decrease hydrogen surface coverage and hydrogen activation at fuel cell conditions. The negative effect on Nafion components was to decrease proton conductivity, primarily by replacing/reacting with the protons on the Bronsted acid sites of the Nafion. Even though already well known as fuel cell poisons, the effects of CO and NH3 were studied in great detail early on in the project in order to develop methodology for evaluating poisoning effects in general, to help establish reproducibility of results among a number of laboratories in the U.S. investigating impurity effects, and to help establish lower limit standards for impurities during hydrogen production for fuel cell utilization. New methodologies developed included (1) a means to measure hydrogen surface concentration on the Pt catalyst (HDSAP) before and after exposure to impurities, (2) a way to predict conductivity of a Nafion membranes exposed to impurities using a characteristic acid catalyzed reaction (methanol esterification of acetic acid), and, more importantly, (3) application of the latter technique to predict conductivity on Nafion in the catalyst layer of the MEA. H2-D2 exchange was found to be suitable for predicting hydrogen activation of Pt catalysts. The Nafion (ca. 30 wt%) on the Pt/C catalyst resides primarily on the external surface of the C support where it blocks significant numbers of micropores, but only partially blocks the pore openings of the meso- and macro-pores wherein lie the small Pt particles (crystallites). For this reason, even with 30 wt% Nafion on the Pt/C, few Pt sites are blocked and, hence, are accessible for hydrogen activation. Of the impurities studied, CO, NH3, perchloroethylene (also known as tetrachloroethylene), tetrahydrofuran, diborane, and metal cations had significant negative effects on the components in a fuel cell. While CO has no effect on the Nafion, it significantly poisons the Pt catalyst by adsorbing and blocking hydrogen activation. The effect can be reversed with time once the flow of CO is stopped. NH3 has no effect on the Pt catalyst at fuel cell conditions; it poisons the proton sites on Nafion (by forming NH4+ cations), decreasing drastically the proton conductivity of Nafion. This poisoning can slowly be reversed once the flow of NH3 is stopped. Perchloroethylene has a major effect on fuel cell performance. Since it has little/no effect on Nafion conductivity, its poisoning effect is on the Pt catalyst. However, this effect takes place primarily for the Pt catalyst at the cathode, since the presence of oxygen is very important for this poisoning effect. Tetrahydrofuran was shown not to impact Nafion conductivity; however, it does affect fuel cell performance. Therefore, its primary effect is on the Pt catalyst. The effect of THF on fuel cell performance is reversible. Diborane also can significant affect fuel cell performance. This effect is reversible once diborane is removed from the inlet streams. H2O2 is not an impurity usually present in the hydrogen or oxygen streams to a fuel cell. However, it is generated during fuel cell operation. The presence of Fe cations in the Nafion due to system corrosion and/or arising from MEA production act to catalyze the severe degradation of the Nafion by H2O2. Finally, the presence of metal cation impurities (Na+, Ca 2+, Fe3+) in Nafion from MEA preparation or from corrosion significantly impacts its proton conductivity due to replacement of proton sites. This effect is not reversible. Hydrocarbons, such as ethylene, might be expected to affect Pt or Nafion but do not at a typical fuel cell temperature of 80oC. In the presence of large quantities of hydrogen on the anode side, ethylene i

  12. alternating chemoradiotherapy consisting: Topics by E-print Network

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    Sciences Websites Summary: Sequential Consistency for Heterogeneous-Race-Free DEREK R. HOWER, BRADFORD M. BECKMANN, BENEDICT R: Sequential Consistency for Data-Race-Free (SC for...

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  14. archaeological record consistent: Topics by E-print Network

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

    Sciences Websites Summary: Sequential Consistency for Heterogeneous-Race-Free DEREK R. HOWER, BRADFORD M. BECKMANN, BENEDICT R: Sequential Consistency for Data-Race-Free (SC for...

  15. air regulations consistency: Topics by E-print Network

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

    Sciences Websites Summary: Sequential Consistency for Heterogeneous-Race-Free DEREK R. HOWER, BRADFORD M. BECKMANN, BENEDICT R: Sequential Consistency for Data-Race-Free (SC for...

  16. Effect of particle size and volume fraction on tensile properties of fly ash/polyurea composites

    E-Print Network [OSTI]

    Nemat-Nasser, Sia

    Effect of particle size and volume fraction on tensile properties of fly ash/polyurea composites polyurea and the polyurea matrix for the composites based on Isonate® 2143L (diisocyanate) and Versalink® P of the composites. Particle size and volume fraction were varied to study their effects on the tensile properties

  17. High temperature behavior of electrostatic precipitator ash from municipal solid waste combustors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    combustors Lydie Le Forestier a,*, Guy Libourel b,c a ISTO, UMR 6113 CNRS-Université d'Orléans, Polytech, a destruction of pathogenic agents and a possible recovery of energy. Whatever MSW combustor used, combustion of MSW produces two kinds of solid residues: (i) bottom ashes recovered from the primary combustor

  18. High-Carbon Fly Ash in Manufacturing Conductive CLSM and Concrete

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    ; Slurries; Steel fibers; Recycling. Introduction In response to Phase II of the Clean Air Act Amendments of 1990, many electric utilities operating coal-fired power plants installed low NOx nitrogen oxides it in nonconcrete applications. The physical characteristics of the coal fly ash vary widely and depend on the type

  19. Optimization of cement and fly ash particle sizes to produce sustainable concretes Dale P. Bentz a,

    E-Print Network [OSTI]

    Bentz, Dale P.

    Optimization of cement and fly ash particle sizes to produce sustainable concretes Dale P. Bentz a and Technology, 100 Bureau Drive, Stop 7313, Gaithersburg, MD 20899-7313, USA b Roman Cement LLC, Salt Lake City form 29 April 2011 Accepted 30 April 2011 Available online 7 May 2011 Keywords: Blended cement Design

  20. TRACE METAL CONTENT OF COAL AND ASH AS DETERMINED USING SCANNINGELECTRON MICROSCOPYWITE

    E-Print Network [OSTI]

    Laughlin, Robert B.

    TRACE METAL CONTENT OF COAL AND ASH AS DETERMINED USING SCANNINGELECTRON MICROSCOPYWITE WAVELENGTH Grand Forks, ND 58202-9018 Keywords: scanning electron microscopy, trace metals, coal analysis ABSTRACT Scanningelectron microscopy with wavelength-dispersive spectrometry has been used to measure trace metals in coal

  1. The impact of conversion to low-NO{sub x} burners on ash characteristics

    SciTech Connect (OSTI)

    Robi, T.L.; Hower, J.C.; Graham, U.M.; Groppo, J.G.; Rathbone, R.F.; Taulbee, D.N. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Medina, S.S. [East Kentucky Power Cooperative, Winchester, KY (United States)

    1995-12-31T23:59:59.000Z

    A research initiative focusing on the changes in coal-combustion byproducts that result from the conversion of coal-fired boilers to low-NO{sub x} burners has been implemented at the Center for Applied Energy Research (CAER). This paper presents selected results from the first such study, the conversion of East Kentucky Power`s 116 MW, wall-fired unit {number_sign}1 at the John Sherman Cooper Station in Pulaski County, Kentucky. Samples of the coal feedstock and fly ash recovered in several downstream collection vessels were collected prior to and following conversion and extensively analyzed. The results presented in this report include total carbon, petrography, mineralogy, particle size, and leaching characteristics. The major changes noted in the fly-ash properties include an increase in carbon content, a slight increase in particle size, and a decrease in glassy components in the ash following conversion. Those changes induced by the conversion to low-NO{sub x} burners are evaluated in terms of the potential impact on the marketability of the fly ash.

  2. Evaluation of leaching and ecotoxicological properties of sewage sludge-fly ash mixtures

    SciTech Connect (OSTI)

    C.A. Papadimitriou; I. Haritou; P. Samaras; A.I. Zouboulis [Technological Educational Institute of West Macedonia, Kozani (Greece)

    2008-03-15T23:59:59.000Z

    The objectives of this work were the evaluation of sewage sludge stabilization by mixing with fly ash, the examination of the physicochemical properties of the produced materials and their leachates and the assessment of their environmental impact by the evaluation of the ecotoxic characteristics. Different ratios of fly ash and sewage sludge (1:1, 1:2, 1:3, 1:6, and 1:9) were mixed for 48 and 72 h. After mixing, the liquid phase of the produced materials was analyzed for total coliforms and Escherichia coli, while the solid residue was dried and tested for the leaching characteristics by the application of TCLP and EN 12457-2 standard leaching methods. Furthermore, the produced leachates were analyzed for their content of specific metals, while their ecotoxicological characteristics were determined by the use of toxicity bioassays, using the marine photobacterium Vibrio fischeri and the crustacean Daphnia magna. The phytotoxicity of sewage sludge-fly ash mixtures was also determined by utilizing seeds of three higher plants (one monocotyl and two dicotyls). The mixtures exhibited low metal leaching in all cases, while the ecotoxic properties increased with the increase of fly ash/sewage sludge ratio. The phytotoxicity testing showed increased root length growth inhibition.

  3. How carbon-based sorbents will impact fly ash utilization and disposal

    SciTech Connect (OSTI)

    Pflughoeft-Hassett, D.F.; Hassett, D.J.; Buckley, T.D.; Heebink, L.V.; Pavlish, J.H. [Energy and Environmental Research Center (United States)

    2008-07-01T23:59:59.000Z

    The injection of activated carbon flue gas to control mercury emissions will result in a fly ash and activated carbon mixture. The potential impact of this on coal combustion product disposal and utilization is discussed. The full paper (and references) are available at www.acaa-usa.org. 1 tab., 2 photos.

  4. Fibrous Fillers to Manufacture Ultra-High Ash/Performance Paper

    Broader source: Energy.gov [DOE]

    This factsheet describes a research project whose goal is to demonstrate the economic and technological viability of fibrous filler to manufacture paper containing up to 50% ash, at equal or better quality and performance than conventional alternatives and at a lower cost.

  5. Mineral sequestration of CO2 by aqueous carbonation of1 coal combustion fly-ash2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Mineral sequestration of CO2 by aqueous carbonation of1 coal combustion fly-ash2 3 G. Montes that could possibly4 contribute to reducing carbon dioxide emissions is the in-situ mineral sequestration (long term5 geological storage) or the ex-situ mineral sequestration (controlled industrial reactors

  6. Optimizing recovery using on-line ash analyzers or sorting for dollars

    SciTech Connect (OSTI)

    Litz, P.

    1995-08-01T23:59:59.000Z

    The quest for profitability in the complex coal industry requires continual examination of common practices looking for better and more cost effective methods of performing these tasks. As the available coal reserves become more difficult to mine and the quality decreases, this examination process grows in importance. Over the past fifteen years, we have all seen major changes in the methods used to mine, clean and load coal in an attempt to increase the bottom line and proliferate a safer work place. The long wall mining method has greatly increased the profitably of the larger mines that have the reserves and the seams suitable for this method. Bigger and faster conveyor belts have increased loading capacities and decreased time spent performing the task. New technology in the cleaning and preparation of coal has also assisted in increasing yield and thus decreasing the final cost of a ton of coal. What about the smaller mines that do not have the mining conditions or reserves for a longwall or the monetary resources to upgrade belt lines and preparation plants, they to must remain profitable. The on-line ash analyzer is one answer that is not only for the smaller mines but can show quick and substantial returns for the larger operations. The on-line ash analyzer is a nuclear device that is mounted directly on the conveyor belt to produce an instantaneous ash analysis on the coal as it moves beneath the detector. The on-line ash analyzer is described.

  7. Dewatering Fly Ash Slurries Using Geotextile Containers M. E. Kutay1

    E-Print Network [OSTI]

    Aydilek, Ahmet

    during its settlement. However, the hydraulic compatibility of a geotextile with the contact soil is also for ensuring hydraulic compatibility is that the geotextile should not be clogged during the dewatering process ash slurries. A testing program that included filter press and hanging bag tests was implemented

  8. Evaluation of Leaching Protocols for Testing of High-Carbon Coal Fly AshSoil Mixtures

    E-Print Network [OSTI]

    Aydilek, Ahmet

    from coal-fired power plants, which burn over 1 billion t of coal annually (Kim 2006). This generationEvaluation of Leaching Protocols for Testing of High-Carbon Coal Fly Ash­Soil Mixtures Jason Becker: Beneficial reuse of coal combustion byproducts, e.g., in highway construction, requires an evaluation

  9. Fish Health Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010

    SciTech Connect (OSTI)

    Adams, Marshall [ORNL; Fortner, Allison M [ORNL

    2012-05-01T23:59:59.000Z

    On December 22, 2008, over 4 million cubic meters of fly ash slurry was released into the Emory River when a dike surrounding a solid waste containment area at the Tennessee Valley Authority's (TVA) Kingston Fossil Plant ruptured. One component of TVA's response to the spill is a biological monitoring program to assess short- and long-term ecological responses to the ash and associated chemicals, including studies on fish health and contaminant bioaccumulation. These studies were initiated in early Spring 2009 for the purposes of: (1) documenting the levels of fly ash-associated metals in various tissues of representative sentinel fish species in the area of the fly ash spill, (2) determining if exposure to fly ash-associated metals causes short, intermediate, or long-term health effects on these sentinel fish species, (3) assessing if there are causal relationships between exposure to metals and health effects on fish, (4) evaluating, along with information from other ecological and physicochemical studies, the nature and route of contaminant transfer though food chains into higher level consumers, (5) providing important information for the Ecological Risk Assessment (ERA) for the Kingston fly ash project, and (6) serving as an important technology information transfer or model study focused on how to best evaluate the environmental effects of fly ash (and related environmental stressors), not only at the Kingston site, but also at sites on other aquatic systems where coal-fired generating stations are located. This report presents the results of the first two years of the fish health study. To date, fish health and bioaccumulation studies have been conducted from Spring 2009 though Fall 2011 and includes 6 seasonal studies: Spring 2009, Fall 2009, Spring 2010, Fall 2010, Spring 2011, and Fall 2011. Both the Spring and Fall studies have focused on 3-4 sentinel fish species that represent different feeding habits, behaviors, and home ranges. In addition to fish health and bioaccumulation, the Spring investigations also included reproductive integrity studies on the same fish used for bioaccumulation and fish health. In this report, results of the fish health studies from Spring 2009 through Fall 2010 are presented while an associated report will present the fish reproductive studies conducted during Spring 2009 and Spring 2010. A report on fish bioaccumulation was submitted to TVA in June 2011. The fish health study conducted in conjunction with the bioaccumulation and reproductive study is critical for assessing and evaluating possible causal relationships between contaminant exposure (bioaccumulation) and the response of fish to exposure as reflected by the various measurements of fish health.

  10. Quasiparticle resonant states induced by a unitary impurity in a d-wave superconductor 

    E-Print Network [OSTI]

    Zhu, JX; Lee, TK; Ting, CS; Hu, Chia-Ren.

    2000-01-01T23:59:59.000Z

    that ~i! a particle-hole symmetric LDOS regardless of the size of the superconducting coherenc case, an asymmetric splitting of the zero-energy peak It is now well established1 that high-Tc superconductors ~HTSC?s! have essentially a dx22y2-wave...I with I the index for the impurity site. The slave- boson method19 is employed to write the electron operator as c is5b i ? f is , where f is and b i are the operators for a spinon ~a neutral spin- 12 fermion! and a holon ~a spinless charged bo- son...

  11. Impurity-induced local density of states in a d-wave superconductor carrying a supercurrent

    E-Print Network [OSTI]

    Zhang, DG; Ting, CS; Hu, Chia-Ren.

    2005-01-01T23:59:59.000Z

    2sqs,ivnd ? asqs,ivndbsqs,ivnd . s5d Obviously, when a supercurrent is applied, the quasiparti- cle energy has a momentum-dependent shift 1 /2sek+qs ?e ?k+qsd fsee the bare Green?s function Gkn0 sqs , ivnd in Eq.s5dg, which leads to different... of the bias energies and the strength of Js, and it has the strongest intensity at the sites next to the defect when the quasiparticle energy sor the bias voltage times ed v=0 meV fsee Fig. 2scd s0dg. Near the impurity, the LDOS has a pattern of fourfold...

  12. Commercial Demonstration of the Manufactured Aggregate Processing Technology Utilizing Spray Dryer Ash

    SciTech Connect (OSTI)

    Milton Wu; Paul Yuran

    2006-12-31T23:59:59.000Z

    Universal Aggregates LLC (UA) was awarded a cost sharing Co-operative Agreement from the Department of Energy (DOE) through the Power Plant Improvement Initiative Program (PPII) to design, construct and operate a lightweight aggregate manufacturing plant at the Birchwood Power Facility in King George, Virginia in October 2001. The Agreement was signed in November 2002. The installation and start-up expenses for the Birchwood Aggregate Facility are $19.5 million. The DOE share is $7.2 million (37%) and the UA share is $12.3 million (63%). The original project team consists of UA, SynAggs, LLC, CONSOL Energy Inc. and P. J. Dick, Inc. Using 115,000 ton per year of spray dryer ash (SDA), a dry FGD by-product from the power station, UA will produce 167,000 tons of manufactured lightweight aggregate for use in production of concrete masonry units (CMU). Manufacturing aggregate from FGD by-products can provide an economical high-volume use and substantially expand market for FGD by-products. Most of the FGD by-products are currently disposed of in landfills. Construction of the Birchwood Aggregate Facility was completed in March 2004. Operation startup was begun in April 2004. Plant Integration was initiated in December 2004. Integration includes mixing, extrusion, curing, crushing and screening. Lightweight aggregates with proper size gradation and bulk density were produced from the manufacturing aggregate plant and loaded on a stockpile for shipment. The shipped aggregates were used in a commercial block plant for CMU production. However, most of the production was made at low capacity factors and for a relatively short time in 2005. Several areas were identified as important factors to improve plant capacity and availability. Equipment and process control modifications and curing vessel clean up were made to improve plant operation in the first half of 2006. About 3,000 tons of crushed aggregate was produced in August 2006. UA is continuing to work to improve plant availability and throughput capacity and to produce quality lightweight aggregate for use in commercial applications.

  13. Influence of conversion to low NO{sub x} combustion on fly ash petrology and mineralogy: A case study

    SciTech Connect (OSTI)

    Robl, T.L.; Hower, J.C.; Graham, U.M.; Rathbone, R.F. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Medina, S.S. [East Kentucky Power Cooperative, Winchester, KY (United States)

    1995-12-31T23:59:59.000Z

    The wall-fired 116 MW unit 2 at the John Sherman Cooper Station, Pulaski County, Kentucky, was converted to low-NO{sub x} combustion in the winter of 1993--1994. The fly ash from before and after conversion was studied in detail. The coal feed, which did not change significantly over the study, was from southeastern Kentucky and had an ash range of 10--12% and a sulfur range of 1.5--1.9%. The coal rank was high volatile bituminous A with a vitrinite reflectance (R{sub max}) of about 0.8%. The coal had about 17% by volume inertinite macerals (mineral-free basis). The fly ash carbon can be divided into three types: anisotropic coke, isotropic coke and inertinite. The post-conversion fly ash has nearly twice the amount of carbon as the pre-conversion ash and shows an increase in anisotropic coke. Mullite and quartz were observed petrographically to be more abundant in the post-conversion fly ash, although only the mullite increase was confirmed by XRD. The proportion of glass is slightly less in the post-conversion ash and is accompanied by one-third drop in the amount of cenospheres.

  14. Hot-gas desulfurization. II. Use of gasifier ash in a fluidized-bed process. Final report

    SciTech Connect (OSTI)

    Schrodt, J.T.

    1981-02-01T23:59:59.000Z

    Three gasifier coal ashes were used as reactant/sorbents in batch fluidized-beds to remove hydrogen sulfide from hot, made-up fuel gases. It is predominantly the iron oxide in the ash that reacts with and removes the hydrogen sulfide; the sulfur reappears in ferrous sulfide. Sulfided ashes were regenerated by hot, fluidizing streams of oxygen in air; the sulfur is recovered as sulfur dioxide, exclusively. Ash sorption efficiency and sulfur capacity increase and stabilize after several cycles of use. These two parameters vary directly with the iron oxide content of the ash and process temperature, but are independent of particle size in the range 0.01 - 0.02 cm. A western Kentucky No. 9 ash containing 22 weight percent iron as iron oxide sorbed 4.3 weight percent sulfur at 1200/sup 0/F with an ash sorption efficiency of 0.83 at ten percent breakthrough. A global, fluidized-bed, reaction rate model was fitted to the data and it was concluded that chemical kinetics is the controlling mechanism with a predicted activation energy of 19,600 Btu/lb mol. Iron oxide reduction and the water-gas-shift reaction were two side reactions that occurred during desulfurization. The regeneration reaction occurred very rapidly in the fluid-bed regime, and it is suspected that mass transfer is the controlling phenomenon.

  15. Case study of the conversion of tangential- and wall-fired units to low-NO{sub x} combustion: Impact on fly ash quality

    SciTech Connect (OSTI)

    Hower, J.C.; Rathbone, R.F.; Robl, T.L.; Thomas, G.A. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research] [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; Haeberlin, B.O. [LG and E Energy Corp., Louisville, KY (United States)] [LG and E Energy Corp., Louisville, KY (United States); Trimble, A.S. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research] [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research; [Franklin County High School, Frankfort, KY (United States)

    1998-07-01T23:59:59.000Z

    Conversion of boilers to low-NO{sub x} combustion can influence fly ash quality in terms of the amount and forms of carbon, the overall fly ash fineness, and the relative amount of glass versus crystalline inorganic phases. All of these factors can influence the potential for a fly ash to be marketed for utilization. In this study, three coal-fired combustors, two tangentially fired and one wall-fired, all burning high-sulfur Illinois coal at the same power plant, were studied before and after conversion to low-NO{sub x} combustion. In all cases, the post-conversion fly ash was higher in carbon than the pre-conversion ash from the same unit. The fly ashes in at least two of the units would appear to have post-conversion ashes which still fall within the regional guidelines for the limit of carbon (or loss on ignition).

  16. Integrated production/use of ultra low-ash coal, premium liquids and clean char. [Quarterly] report, December 1, 1991--February 29, 1992

    SciTech Connect (OSTI)

    Kruse, C.W. [Illinois State Geological Survey, Champaign, IL (United States)

    1992-08-01T23:59:59.000Z

    The first step in the integrated, mufti-product approach for utilizing Illinois coal is the production of ultra low-ash coal. Subsequent steps convert low-ash coal to high-value, coal-derived, products. The ultra low-ash coal is produced by solubilizing coal in a phenolic solvent under ChemCoal{trademark} process conditions, separating the coal solution from insoluble ash, and then precipitating the clean coal by dilution of the solvent with methanol. Two major products, liquids and low-ash char, are then produced by mild gasification of the low-ash coal. The low ash-char is further upgraded to activated char, and/or an oxidized activated char which has catalytic properties. Characterization of products at each stage is part of this project.

  17. Surface and bulk studies of leached and unleached fly ash using XPS, SEM, EDS and FTIR techniques

    SciTech Connect (OSTI)

    Yousuf, M.; Mollah, A.; Hess, T.R.; Cocke, D.L. [Lamar Univ., Beaumont, TX (United States). Gill Chair of Chemistry

    1994-04-01T23:59:59.000Z

    The effective chemical utilization of fly ash in environmental applications requires a detailed knowledge of the surface and bulk changes induced by leaching in acid solutions. The surface and bulk characteristics of fly ash from the combustion of Texas lignite have been examined by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). The effects of leaching with acid solutions commonly used in environmental studies have been documented using these techniques. The results of these studies reveal that the fly ash particles are relatively resistance to either chemical or physical changes due to attack by acidic leaching solutions.

  18. A fast spectroscopic diagnostic for the measurement of plasma impurity ion dynamics

    SciTech Connect (OSTI)

    Den Hartog, D.J.; Fonck, R.J.

    1994-04-01T23:59:59.000Z

    A high-resolution spectrometer has been developed and used to measure simultaneously impurity ion temperature and flow velocities in high temperature plasmas with 10 {mu}s temporal resolution (limited by digitization rate). This device is actually a duo-spectrometer: measurements from two different chordal views of the plasma can be made simultaneously via two separate quartz input fiber optic bundles coupled to the entrance slits which are tilted to compensate for line curvature. The dispersed spectra on the exit plane of the duo-spectrometer are coupled via quartz fiber optics to two arrays of 16 photomultiplier tubes each. Measurement made by recording the Doppler broadened and shifted 227.091 nm emission from the CV impurity ions in the MST reversed-field pinch (RFP) plasma have achieved precisions of <6 eV for temperatures of 150 Ev and <0.7 km/s for flow velocities of 6 km/s. Representative results from the MsT RFP indicate that the toroidal flow velocity drops and ion temperature increases during saw tooth events in MST.

  19. Determination of elemental impurities in plastic calibration standards using laser induced breakdown spectroscopy

    SciTech Connect (OSTI)

    McIntyre, D.; Ayyalasomayajula, K.; Jain, J.; Singh, J.; Yu-Yueh, F.

    2012-01-01T23:59:59.000Z

    Dual-energy computed tomography (CT) scanning is a rapidly emerging imaging technique employed in nondestructive evaluation of various materials. CT has been used for characterizing rocks and visualizing multiphase flow through rocks for over 25 years. The most common technique for dual-energy CT scanning relies on homogeneous calibration standards to produce the most accurate decoupled data. However, the use of calibration standards with impurities increases the probability of error in the reconstructed data and results in poor rock characterization. Laser-induced breakdown spectroscopy was used to determine impurity concentration in a set of commercially purchased calibration standards used in dual-energy scanning for material identification with coal samples. Two calibration models were developed by using univariate calibration with the internal ratio method and multiple linear regression. Seven elements (Al, Fe, Mg, Na, Ni, Sr, and Ti) were examined in five different samples containing varying amounts of each ion to compare calibration from univariate data analysis and from multivariate data analysis. The contaminant concentrations were also measured by a commercially available inductively coupled plasma optical emission spectroscopy instrument, and the data were used as a reference in developing calibration curves for a modified version of the single linear regression model and the multiple linear regression model.

  20. Advanced far infrared blocked impurity band detectors based on germanium liquid phase epitaxy

    SciTech Connect (OSTI)

    Olsen, C.S. [Lawrence Berkeley National Lab., CA (United States). Engineering Div.]|[Univ. of California, Berkeley, CA (United States). Materials Science and Mineral Engineering Dept.

    1998-05-01T23:59:59.000Z

    This research has shown that epilayers with residual impurity concentrations of 5 x 10{sup 13} cm{sup {minus}3} can be grown by producing the purest Pb available in the world. These epilayers have extremely low minority acceptor concentrations, which is ideal for fabrication of IR absorbing layers. The Pb LPE growth of Ge also has the advantageous property of gettering Cu from the epilayer and the substrate. Epilayers have been grown with intentional Sb doping for IR absorption on lightly doped substrates. This research has proven that properly working Ge BIB detectors can be fabricated from the liquid phase as long as pure enough solvents are available. The detectors have responded at proper wavelengths when reversed biased even though the response did not quite reach minimum wavenumbers. Optimization of the Sb doping concentration should further decrease the photoionization energy of these detectors. Ge BIB detectors have been fabricated that respond to 60 cm{sup {minus}1} with low responsivity. Through reduction of the minority residual impurities, detector performance has reached responsivities of 1 A/W. These detectors have exhibited quantum efficiency and NEP values that rival conventional photoconductors and are expected to provide a much more sensitive tool for new scientific discoveries in a number of fields, including solid state studies, astronomy, and cosmology.

  1. An impurity-induced gap system as a quantum data bus for quantum state transfer

    E-Print Network [OSTI]

    Bing Chen; Yong Li; Z. Song; C. -P. Sun

    2015-01-02T23:59:59.000Z

    We introduce a tight-binding chain with a single impurity to act as a quantum data bus for perfect quantum state transfer. Our proposal is based on the weak coupling limit of the two outermost quantum dots to the data bus. First show that the data bus has an energy gap between the ground and first-excited states in the single-particle case induced by the impurity in the single particle case. By connecting two quantum dots to two sites of the data bus, the system can accomplish a high-fidelity and long-distance quantum state transfer. Numerical simulations were performed for a finite system; the results show that the numerical and analytical results of the effective coupling strength agree well with each other. Moreover, we study the robustness of this quantum communication protocol in the presence of disorder in the couplings between the nearest-neighbor quantum dots. We find that the gap of the system plays an important role in robust quantum state transfer.

  2. Impurity Diffusion Coefficients of Al and Zn in Mg Determined from Solid-to-Solid Diffusion Couples

    SciTech Connect (OSTI)

    Kammerer, Catherine [University of Central Florida, Orlando; Kulkarni, Nagraj S [ORNL; Warmack, Robert J Bruce [ORNL; Perry, Kelly A [ORNL; Belova, Irina [University of Newcastle, NSW, Australia; Murch, Prof. Graeme [University of Newcastle, NSW, Australia; Sohn, Yong Ho [University of Central Florida

    2013-08-01T23:59:59.000Z

    Increasing use and development of lightweight Mgalloys have led to the desire for more fundamental research in and understanding of Mg-based systems. As property enhancing components, Al and Zn are two of the most important and common alloying elements for Mg-alloys. We have investigated the concentration dependent interdiffusion of Al and Zn in Mg using diffusion couples of pure polycrystalline Mg mated to Mg solid solutions containing either <9 at.% Al or <3 at.% Zn. Concentration profiles were determined by electron micro-probe microanalysis of the diffusion zone. The interdiffusion coefficients were determined by the classical Boltzmann-Matano method within the Mg solid solution. As the concentration of Al or Zn approaches the dilute ends, we employ an analytical approach based on the Hall method to estimate the impurity diffusion coefficients. Results of Al and Zn impurity diffusion in Mg are reported and compared to published impurity diffusion coefficients typically determined by thin film techniques.

  3. EVALUATING THE EFFECTS OF FLY ASH EXPOSURE ON FISH EARLY LIFE STAGES: FATHEAD MINNOW EMBRYO-LARVAL TESTS

    SciTech Connect (OSTI)

    Greeley Jr, Mark Stephen [ORNL; Elmore, Logan R [ORNL; McCracken, Kitty [ORNL

    2012-05-01T23:59:59.000Z

    On December 22, 2008, a dike containing fly ash and bottom ash in an 84-acre complex of the Tennessee Valley Authority's (TVA) Kingston Steam Plant in East Tennessee failed and released a large quantity of ash into the adjacent Emory River. Ash deposits extended as far as 4 miles upstream (Emory River mile 6) of the Plant, and some ash was carried as far downstream as Tennessee River mile 564 ({approx}4 miles downstream of the Tennessee River confluence with the Clinch River). A byproduct of coal burning power plants, fly ash contains a variety of metals and other elements which, at sufficient concentrations and in specific forms, can be toxic to biological systems. The effects of fly ash contamination on exposed fish populations depend on the magnitude and duration of exposure, with the most significant risk considered to be the effects of specific ash constituents, especially selenium, on fish early life stages. Uptake by adult female fish of fly ash constituents through the food chain and subsequent maternal transfer of contaminants to the developing eggs is thought to be the primary route of selenium exposure to larval fish (Woock and others 1987, Coyle and others 1993, Lemly 1999, Moscatello and others 2006), but direct contact of the fertilized eggs and developing embryos to ash constituents in river water and sediments is also a potential risk factor (Woock and others 1987, Coyle and others 1993, Jezierska and others 2009). To address the risk of fly ash from the Kingston spill to the reproductive health of downstream fish populations, ORNL has undertaken a series of studies in collaboration with TVA including: (1) a field study of the bioaccumulation of fly ash constituents in fish ovaries and the reproductive condition of sentinel fish species in reaches of the Emory and Clinch Rivers affected by the fly ash spill; (2) laboratory tests of the potential toxicity of fly ash from the spill area on fish embryonic and larval development (reported in the current technical manuscript); (3) additional laboratory experimentation focused on the potential effects of long-term exposures to fly ash on fish survival and reproductive competence; and (4) a combined field and laboratory study examining the in vitro developmental success of embryos and larvae obtained from fish exposed in vivo for over two years to fly ash in the Emory and Clinch Rivers. These fish reproduction and early life-stage studies are being conducted in conjunction with a broader biological monitoring program administered by TVA that includes a field study of the condition of larval fish in the Emory and Clinch Rivers along with assessments of water quality, sediment composition, ecotoxicological studies, terrestrial wildlife studies, and human and ecological risk assessment. Information and data generated from these studies will provide direct input into risk assessment efforts and will also complement and help support other phases of the overall biomonitoring program. Fish eggs, in general, are known to be capable of concentrating heavy metals and other environmental contaminants from water-borne exposures during embryonic development (Jezierska and others 2009), and fathead minnow embryos in particular have been shown to concentrate methylmercury (Devlin 2006) as well as other chemical toxicants. This technical report focuses on the responses of fathead minnow embryos to simple contact exposures to fly ash in laboratory toxicity tests adapted from a standard fathead minnow (Pimephales promelas) 7-d embryo-larval survival and teratogenicity test (method 1001.0 in EPA 2002) with mortality, hatching success, and the incidences of developmental abnormalities as measured endpoints.

  4. Long-range ferromagnetic order induced by a donor impurity band exchange in SnO{sub 2}:Er{sup 3+} nanoparticles

    SciTech Connect (OSTI)

    Aragón, F. H.; Coaquira, J. A. H. [Núcleo de Física Aplicada, Institute of Physics, University of Brasília, Brasília DF 70910-900 (Brazil); Chitta, V. A. [Instituto de Física, Universidade de São Paulo, São Paulo, SP 05508-000 (Brazil); Hidalgo, P. [Faculdade Gama-FGA, Sector Central Gama, Universidade de Brasília, Brasília, DF72405-610 (Brazil); Brito, H. F. [Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000 (Brazil)

    2013-11-28T23:59:59.000Z

    In this work, the structural and magnetic properties of Er-doped SnO{sub 2} (SnO{sub 2}:Er) nanoparticles are reported. The SnO{sub 2}:Er nanoparticles have been synthesized by a polymer precursor method with Er content from 1.0% to 10.0%. X-ray diffraction results indicate the formation of only the rutile-type structure in all samples. The estimated mean crystallite size shows a decrease from ?10 to ?4?nm when the Er content is increased from 1.0% to 10.0%. The particle size values have been corroborated by transmission electron microscopy technique. The thermal dependence of the magnetization is consistent with the 3+ oxidation state of erbium ions for all samples. A strong paramagnetic-like behavior coexisting with a ferromagnetic phase has been determined for samples with Er content below 5.0%. Above this concentration, only a paramagnetic behavior has been determined. Isothermal magnetization curves are consistent with the occurrence of long-range ferromagnetic order mediated by donor electrons forming bound magnetic polarons which overlap to produce a spin-split impurity band.

  5. A calibration to predict the concentrations of impurities in plutonium oxide by prompt gamma analysis: Revision 1

    SciTech Connect (OSTI)

    Narlesky, Joshua E.; Foster, Lynn A.; Kelly, Elizabeth J.; Murray, Roy E., IV

    2009-12-01T23:59:59.000Z

    Over 5,500 containers of excess plutonium-bearing materials have been packaged for long-term storage following the requirements of DOE-STD- 3013. Knowledge of the chemical impurities in the packaged materials is important because certain impurities, such as chloride salts, affect the behavior of the material in storage leading to gas generation and corrosion when sufficient moisture also is present. In most cases, the packaged materials are not well characterized, and information about the chemical impurities is limited to knowledge of the material’s processing history. The alpha-particle activity from the plutonium and americium isotopes provides a method of nondestructive self-interrogation to identify certain light elements through the characteristic, prompt gamma rays that are emitted from alpha-particle-induced reactions with these elements. Gamma-ray spectra are obtained for each 3013 container using a highresolution, coaxial high-purity germanium detector. These gamma-ray spectra are scanned from 800 to 5,000 keV for characteristic, prompt gamma rays from the detectable elements, which include lithium, beryllium, boron, nitrogen, oxygen, fluorine, sodium, magnesium, aluminum, silicon, phosphorus, chlorine, and potassium. The lower limits of detection for these elements in a plutonium-oxide matrix increase with atomic number and range from 100 or 200 ppm for the lightest elements such as lithium and beryllium, to 19,000 ppm for potassium. The peak areas from the characteristic, prompt gamma rays can be used to estimate the concentration of the light-element impurities detected in the material on a semiquantitative basis. The use of prompt gamma analysis to assess impurity concentrations avoids the expense and the risks generally associated with performing chemical analysis on radioactive materials. The analyzed containers are grouped by impurity content, which helps to identify high-risk containers for surveillance and in sorting materials before packaging.

  6. Effect of unitary impurities on non-STM types of tunneling in high-T-c superconductors

    E-Print Network [OSTI]

    Zhu, JX; Ting, CS; Hu, Chia-Ren.

    2000-01-01T23:59:59.000Z

    ?4 or twin5 boundary. These MS?s form an ??essentially dispersionless?? branch of elementary excitations, in the PRB 620163-1829/2000/62~9!/6027~10!/$15.00 s of tunneling in high-Tc superconductors d C. S. Ting , University of Houston, Houston, Texas... that HTSC?s are DWSC?s, and isolated unitary impurities do pos- sess near-zero energy resonant states which can be observed as a ZBCP-like feature by STM/S in the close vicinity of PRB 62, AND CHIA-REN HU such an impurity, can any concentration of a...

  7. Effect of fluorine, nitrogen, and carbon impurities on the electronic and magnetic properties of WO{sub 3}

    SciTech Connect (OSTI)

    Shein, I. R.; Ivanovskii, A. L. [Russian Academy of Sciences, Institute of Solid State Chemistry (Russian Federation)

    2013-06-15T23:59:59.000Z

    Within electron density functional theory with the use of the Vienna ab-initio simulation package (VASP), the effect of the sp substitutional impurities of fluorine (n-type dopant), nitrogen, and carbon (p-type dopants) on the electronic and magnetic properties of tungsten trioxide WO{sub 3} is studied. It is established that these impurities induce the transformation of tungsten trioxide (nonmagnetic semiconductor) into nonmagnetic metal (WO{sub 3}:F), magnetic semimetal (WO{sub 3}:N), or magnetic metal (WO{sub 3}:C) states.

  8. Decentralized Storage Consistency via Versioning Servers Garth Goodson,

    E-Print Network [OSTI]

    , consistency protocol, versioning servers, distributed systems #12; Introduction Survivable storage systems (e produce garbage. Protocols exist for achieving such consistency, they generally involve significant extra], survival client compromises [34]. Further, implemented with minimal performance cost ( [34] and capacity

  9. 18 2010 Proceedings Symposium on Ash in North America GTR-NRS-P-72 GENETIC TRANSFORMATION OF FRAXINUS SPP. FOR

    E-Print Network [OSTI]

    in cold storage. This regeneration system provided a foundation for developing a genetic modification, the nursery and forest products industries, and the U.S. foreign trade of ash lumber and logs. This research

  10. Lubricant oil consumption effects on diesel exhaust ash emissions using a sulfur dioxide trace technique and thermogravimetry

    E-Print Network [OSTI]

    Plumley, Michael J

    2005-01-01T23:59:59.000Z

    A detailed experimental study was conducted targeting lubricant consumption effects on ,diesel exhaust ash levels using a model year 2002 5.9L diesel engine, high and low Sulfur commercial lubricants, and clean diesel ...

  11. Utilizing New Binder Materials for Green Building has Zero Waste by Recycling Slag and Sewage Sludge Ash 

    E-Print Network [OSTI]

    Zeedan, S. R.

    2010-01-01T23:59:59.000Z

    binding material to save energy and to produce new innovative zero materials waste . The current research aims to investigate new binder materials as alternative of Portland cement. Alkali activated slag (AAS) blended with sewage sludge ash (SSA...

  12. Chemical composition and some trace element contents in coals and coal ash from Tamnava-Zapadno Polje Coal Field, Serbia

    SciTech Connect (OSTI)

    Vukasinovic-Pesic, V.; Rajakovic, L.J. [University of Montenegro, Podgorica (Montenegro)

    2009-07-01T23:59:59.000Z

    The chemical compositions and trace element contents (Zn, Cu, Co, Cr, Ni, Pb, Cd, As, B, Hg, Sr, Se, Be, Ba, Mn, Th, V, U) in coal and coal ash samples from Tamnava-Zapadno Polje coal field in Serbia were studied. The coal from this field belongs to lignite. This high volatility coal has high moisture and low S contents, moderate ash yield, and high calorific value. The coal ash is abundant in alumosilicates. Many trace elements such as Ni > Cd > Cr > B > As > Cu > Co > Pb > V > Zn > Mn in the coal and Ni > Cr > As > B > Cu > Co = Pb > V > Zn > Mn in the coal ash are enriched in comparison with Clarke concentrations.

  13. The nature of lubricant-derived ash-related emissions and their impact on diesel aftertreatment system performance

    E-Print Network [OSTI]

    Sappok, Alexander G. (Alexander Georg)

    2009-01-01T23:59:59.000Z

    Diesel particulate filters (DPF) have seen widespread use in on- and off-road applications as an effective means for meeting increasingly stringent particle emissions regulations. Over time, incombustible material or ash, ...

  14. Generalized contexts and consistent histories in quantum mechanics

    SciTech Connect (OSTI)

    Losada, Marcelo [Instituto de Física Rosario, Pellegrini 250, 2000 Rosario (Argentina); Laura, Roberto, E-mail: rlaura@fceia.unr.edu.ar [Facultad de Ciencias Exactas, Ingeniería y Agrimensura, Pellegrini 250, 2000 Rosario (Argentina); Instituto de Física Rosario, Pellegrini 250, 2000 Rosario (Argentina)

    2014-05-15T23:59:59.000Z

    We analyze a restriction of the theory of consistent histories by imposing that a valid description of a physical system must include quantum histories which satisfy the consistency conditions for all states. We prove that these conditions are equivalent to imposing the compatibility conditions of our formalism of generalized contexts. Moreover, we show that the theory of consistent histories with the consistency conditions for all states and the formalism of generalized context are equally useful representing expressions which involve properties at different times.

  15. ORCHIS: CONSISTENCY-DRIVEN DATA QUALITY MANAGEMENT IN SENSING SYSTEMS

    E-Print Network [OSTI]

    Shi, Weisong

    Sensing Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3.3 Related Energy Efficiency Design . . . . . . . . . . . . . . . . . . . . . . . . . 30 3.4 Related Data Consistency Models

  16. 3 Morphology of contact areas The SEM examinations of the YSZ pellets revealed that when an impure nickel wire was used,

    E-Print Network [OSTI]

    3 Morphology of contact areas The SEM examinations of the YSZ pellets revealed that when an impure.1 Samples with impure nickel wires as electrodes The surface of the YSZ pellets may, after the experiments.1. A schematic drawing of a pellet surface after an experiment. A line profile through the contact area is shown

  17. Finite-temperature phase diagram of nonmagnetic impurities in high-temperature superconductors using a d=3 tJ model with quenched disorder

    E-Print Network [OSTI]

    Thirumalai, Devarajan

    Finite-temperature phase diagram of nonmagnetic impurities in high-temperature superconductors to the superconducting phase in cuprates which is eliminated for p 0.05; in the same region for these dilute impurity destruction of the superconducting phase.1,2 In yttrium barium copper oxide YBCO , the transition temperature

  18. Software Agent Architecture for Consistency Management in Distributed Documents

    E-Print Network [OSTI]

    Finkelstein, Anthony

    Software Agent Architecture for Consistency Management in Distributed Documents Anthony Finkelstein an account of an architecture for management of consistency relations between distributed documents. We of use of this system in a domain of software engineering documents. Keywords Consistency management, XML

  19. WELL-FORMEDNESS, CONSISTENCY AND COMPLETENESS OF GRAPHIC MODELS

    E-Print Network [OSTI]

    Zhu, Hong

    WELL-FORMEDNESS, CONSISTENCY AND COMPLETENESS OF GRAPHIC MODELS HONG ZHU Department of Computing@yahoo.com ABSTRACT This paper clarifies the notions of well-formedness, consistency and completeness of graphic languages, Well-formedness, Consistency constraints, Completeness constraints, Type systems, Formal

  20. Characterization of fly ash from low-sulfur and high-sulfur coal sources: Partitioning of carbon and trace elements with particle size

    SciTech Connect (OSTI)

    Hower, J.C.; Trimble, A.S. [Univ. of Kentucky, Lexington, KY (United States). Center for Applied Energy Research]|[Franklin County High School, Frankfort, KY (United States); Eble, C.F. [Kentucky Geological survey, Lexington, KY (United States); Palmer, C.A.; Kolker, A. [Geological Survey, Reston, VA (United States)

    1999-07-01T23:59:59.000Z

    Fly ash samples were collected in November and December of 1994, from generating units at a Kentucky power station using high- and low-sulfur feed coals. The samples are part of a two-year study of the coal and coal combustion byproducts from the power station. The ashes were wet screened at 100, 200, 325, and 500 mesh (150, 75, 42, and 25 {micro}m, respectively). The size fractions were then dried, weighed, split for petrographic and chemical analysis, and analyzed for ash yield and carbon content. The low-sulfur heavy side and light side ashes each have a similar size distribution in the November samples. In contrast, the December fly ashes showed the trend observed in later months, the light-side ash being finer (over 20% more ash in the {minus}500 mesh [{minus}25 {micro}m] fraction) than the heavy-side ash. Carbon tended to be concentrated in the coarse fractions in the December samples. The dominance of the {minus}325 mesh ({minus}42 {micro}m) fractions in the overall size analysis implies, though, that carbon in the fine sizes may be an important consideration in the utilization of the fly ash. Element partitioning follows several patterns. Volatile elements, such as Zn and As, are enriched in the finer sizes, particularly in fly ashes collected at cooler, light-side electrostatic precipitator (ESP) temperatures. The latter trend is a function of precipitation at the cooler-ESP temperatures and of increasing concentration with the increased surface area of the finest fraction. Mercury concentrations are higher in high-carbon fly ashes, suggesting Hg adsorption on the fly ash carbon. Ni and Cr are associated, in part, with the spinel minerals in the fly ash.