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Project Work Plan Chromium Vadose Zone Characterization and Geochemistry

Description: The major objectives of the proposed study are to 1) determine the leaching characteristics of Cr(VI) from contaminated sediments collected from 100 area spill sites, 2) elucidate possible Cr(VI) mineral and/or chemical associations that may be responsible for Cr(VI) retention in the Hanford site 100 areas through the use of i) macroscopic solubility studies and ii) microscale characterization of contaminated sediments, and 3) from these data construct a conceptual model of Cr(VI) geochemistry … more
Date: May 23, 2006
Creator: Ainsworth, Calvin C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstructural Stability and Oxidation Resistance of 9-12 Chromium Steels at Elevated Temperatures

Description: Various martensitic 9-12 Cr steels are utilized currently in fossil fuel powered energy plants for their good elevated temperature properties such as creep strength, steam side oxidation resistance, fire side corrosion resistance, and thermal fatigue resistance. Need for further improvements on the properties of 9-12 Cr steels for higher temperature (>600oC) use is driven by the environmental concerns (i.e., improve efficiency to reduce emissions and fossil fuel consumption). In this paper, we … more
Date: May 1, 2006
Creator: Dogan, O. N.; Alman, D. E.; Jablonski, P. D. & Hawk, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bioreactor Landfill Research and Demonstration Project Northern Oaks Landfill, Harrison, MI

Description: A bioreactor landfill cell with 1.2-acre footprint was constructed, filled, operated, and monitored at Northern Oaks Recycling and Disposal Facility (NORDF) at Harrison, MI. With a filled volume of 74,239 cubic yards, the cell contained approximately 35,317 tons of municipal solid waste (MSW) and 20,777 tons of cover soil. It was laid on the slope of an existing cell but separated by a geosynthetic membrane liner. After the cell reached a design height of 60 feet, it was covered with a geosynth… more
Date: August 29, 2006
Creator: Zhao, Xiando; Voice, Thomas & Hashsham, Syed A.
Item Type: Refine your search to only Report
Location: None
Partner: UNT Libraries Government Documents Department
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Evaluation of the effects of various culture condition on Cr (VI) reduction by Shewanella oneidensis MR-1 in a novel high-throughputmini-bioreactor

Description: The growth and Cr(VI) reduction by Shewanella oneidensisMR-1 was examined using a mini-bioreactor system that independentlymonitors and controls pH, dissolved oxygen, and temperature for each ofits 24, 10-mL reactors. Independent monitoring and control of eachreactor in the cassette allows the exploration of a matrix ofenvironmental conditions known to influence S. oneidensis chromiumreduction. S. oneidensis MR-1 grew in minimal medium without amino acidor vitamin supplementation under aerobic … more
Date: March 16, 2006
Creator: Tang, Yinjie J.; Laidlaw, David; Gani, Kishen & Keasling, Jay D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Functionally Graded Cathodes for Solid Oxide Fuel Cells

Description: One primary suspected cause of long-term performance degradation of solid oxide fuels (SOFCs) is the accumulation of chromium (Cr) species at or near the cathode/electrolyte interface due to reactive Cr molecules originating from Cr-containing components (such as the interconnect) in fuel cell stacks. To date, considerable efforts have been devoted to the characterization of cathodes exposed to Cr sources; however, little progress has been made because a detailed understanding of the chemistry … more
Date: December 31, 2006
Creator: Abernathy, Harry & Liu, Meilin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alloy Films Deposited by Electroplating as Precursors for Protective Oxide Coatings on Solid Oxide Fuel Cells Metallic Interconnect Materials

Description: The successful development of stainless steel interconnects for intermediate temperature solid oxide fuel cells (SOFC) may be the materials breakthrough that makes SOFC technology truly commercial. Many of the ferritic stainless steels, however, suffer from a relatively high area specific resistance (ASR) after long exposure times at temperature and the Cr in the native oxide can evaporate and contaminate other cell components. Conductive coatings that resist oxide scale growth and chromium eva… more
Date: October 1, 2006
Creator: Johnson, Christopher; Gemmen, R. S. & Cross, Caleb
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Post-Closure RCRA Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch

Description: The purpose of this plan is to provide a post-closure groundwater monitoring program for the 216-S-10 Pond and Ditch (S-10) treatment, storage, and/or disposal (TSD) unit. The plan incorporates the sum of knowledge about the potential for groundwater contamination to originate from the S-10, including groundwater monitoring results, hydrogeology, and operational history. The S-10 has not received liquid waste since October 1991. The closure of S-10 has been coordinated with the 200-CS-1 source … more
Date: March 17, 2006
Creator: Barnett, D BRENT.; Williams, Bruce A.; Chou, Charissa J. & Hartman, Mary J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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IN SITU INVESTIGATION OF THE PASSIVATION OF ALLOY C22 AND OF THE PASSIVE FILMS FORMED ON ALLOY C22 IN ACIDIC ELECTROLYTES AT ROOM TEMPERATURE AND AT 90 DEGREES C

Description: The passive films formed on Alloy C22 in several acidic solutions were investigated by a combination of five in situ techniques: cyclic polarization, electrochemical impedance spectroscopy, Mott-Schottky analyses, electrochemical quartz crystal microbalance measurements, and surface enhanced Raman spectroscopy. Similar tests were conducted on unalloyed samples of nickel, chromium and molybdenum, which are the main alloying elements of Alloy C22. The results of the tests conducted on nickel, chr… more
Date: March 11, 2006
Creator: M. Miyagusuku, S. Harrington, and T. M. Devine
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SCC Initiation in Alloy 600 Heat Affected Zones Exposed to High Temperature Water

Description: Studies have shown that grain boundary chromium carbides improve the stress corrosion cracking (SCC) resistance of nickel based alloys exposed to high temperature, high purity water. However, thermal cycles from welding can significantly alter the microstructure of the base material near the fusion line. In particular, the heat of welding can solutionize grain boundary carbides and produce locally high residual stresses and strains, reducing the SCC resistance of the Alloy 600 type material in … more
Date: November 3, 2006
Creator: Richey, E.; Morton, D. S.; Etien, R. A.; Young, G. A. & Bucinell, R. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Field-Integrated Studies of Long-Term Sustainability of Chromium Bioreduction at Hanford 100H Site

Description: The objectives of the project are to investigate coupled hydraulic, geochemical, and microbial conditions, and to determine the critical biogeochemical parameters necessary to maximize the extent of Cr(VI) bioreduction and minimize Cr(III) reoxidation in groundwater. Specific goals of the project are as follows: (1) Field testing and monitoring of Cr(VI) bioreduction in ground water and its transformation into insoluble species of Cr(III) at the Hanford 100H site, to develop the optimal strateg… more
Date: June 1, 2006
Creator: Long, Philip E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Scale Formation and Kinetics of Crofer 22 APU and Haynes 230 in Carbon Oxide-Containing Environment for SOFC Applications

Description: Significant progress in reducing the operating temperature of SOFCs below 800oC may allow the use of chromia-forming metallic interconnects at a substantial cost savings. Hydrogen is the main fuel for all types of fuel cells except direct methanol fuel cells. Hydrogen can be generated from fossil fuels, including coal, natural gas, diesel, gasoline, other hydrocarbons, and oxygenates (e.g., methanol, ethanol, butanol, etc.). Carbon oxides present in the hydrogen fuel can cause significant perfo… more
Date: January 1, 2006
Creator: Ziomek-Moroz, M.; Covino, B. S., Jr.; Holcomb, G. R.; Bullard, S. J. & Penner, L. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Elucidating Bioreductive Transformations within Physically Complex Media: Impact on the Fate and Transport of Uranium and Chromium

Description: Uranium and chromium are two elements of particular concern within the DOE complex that, owing to their abundance and toxicity, appear well suited for biologically mediated reductive stabilization. Subsurface microbial activity can alter the redox state of toxic metals and radionuclides, rending them immobile. Furthermore, anaerobic bacterial metabolic products will help to buffer pulses of oxidation, typically from fluxes of nitrate or molecular oxygen, and thus may stabilize reduced contamina… more
Date: November 1, 2006
Creator: Fendorf, Scott; Francis, Chris; Benner, Shawn & Jardine, Phil
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Field-Integrated Studies of Long-Term Sustainability of Chromium Bioreduction at Hanford 100H Site

Description: The objectives of the project are to investigate coupled hydraulic, geochemical, and microbial conditions, and to determine the critical biogeochemical parameters necessary to maximize the extent of Cr (VI) bioreduction and minimize Cr(III) reoxidation in groundwater.
Date: June 1, 2006
Creator: Long, Phillip E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Results of Groundwater Monitoring for the 183-H Solar Evaporation Basins

Description: The 183-H solar evaporation basins (183-H basins) were located in the 100-H Area of the Hanford Site and have been demolished and backfilled under the Resource Conservation and Recovery Act (RCRA) in the Hanford Facility RCRA Permit (Ecology 2004). Post-closure actions remain for the 183 H basins. Groundwater is monitored in accordance with Washington Administrative Code (WAC) 173 303 645(11), ''Corrective Action Program'', and Part VI, Chapter 2 of the Hanford Facility RCRA Permit (Ecology 200… more
Date: October 31, 2006
Creator: Hartman, Mary J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simultaneous Microscopic Imaging of Elastic and Thermal Anisotropy

Description: Simultaneous imaging of elastic and thermal properties of anisotropic materials with micron (lateral) and nanometer (depth) resolution is presented. This approach employs an ultrafast laser for the generation and detection of thermal and acoustic waves. Demonstrations involving the visualization of thermal waves and surface acoustic waves are presented for single crystal quartz and fused silica substrates supper coated with chromium films. These images dramatically reveal and contrast the symme… more
Date: May 1, 2006
Creator: Hurley, David H. & Telschow, Ken
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and Evaluation of Nanoscale Sorbents for Mercury Capture from Warm Fuel Gas

Description: Several nanocrystalline sorbents were synthesized by GTI's subcontractor NanoScale Materials, Inc. (NanoScale) and submitted to GTI for evaluation. A total of seventeen sorbent formulations were synthesized and characterized by NanoScale, including four existing sorbent formulations (NanoActive{trademark} TiO{sub 2}, NanoActive CeO{sub 2}, NanoActive ZnO, and NanoActive CuO), three developmental nanocrystalline metal oxides (MnO{sub 2}, MoO{sub 3}, and Cr{sub 2}O{sub 3}), and ten supported form… more
Date: March 1, 2006
Creator: Jadhav, Raja A.; Meyer, Howard & Winecki, Slawomir
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Treatability Study of In Situ Technologies for Remediation of Hexavalent Chromium in Groundwater at the Puchack Well Field Superfund Site, New Jersey

Description: This treatability study was conducted by Pacific Northwest National Laboratory (PNNL), at the request of the U. S. Environmental Protection Agency (EPA) Region 2, to evaluate the feasibility of using in situ treatment technologies for chromate reduction and immobilization at the Puchack Well Field Superfund Site in Pennsauken Township, New Jersey. In addition to in situ reductive treatments, which included the evaluation of both abiotic and biotic reduction of Puchack aquifer sediments, natural… more
Date: November 13, 2006
Creator: Vermeul, Vince R.; Szecsody, Jim E.; Truex, Michael J.; Burns, Carolyn A.; Girvin, Donald C.; Phillips, Jerry L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Micron-Size Zero-Valent Iron Emplacement in Porous Media Using Polymer Additives: Column and Flow Cell Ex-periments

Description: At the Hanford Site, an extensive In Situ Redox Manipulation (ISRM) permeable reactive barrier was installed to prevent chromate from reaching the Columbia River. However, chromium has been detected in several wells, indicating a premature loss of the reductive capacity in the aquifer. Laboratory experiments have been conducted to investigate whether barrier reductive capacity can be enhanced by adding micron-scale zero-valent iron to the high-permeability zones within the aquifer using shear-t… more
Date: March 20, 2006
Creator: Oostrom, Mart; Wietsma, Thomas W.; Covert, Matthew A. & Vermeul, Vince R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cross-Roll Flow Forming of ODS Alloy Heat Exchanger Tubes For Hoop Creep Enhancement, Quarterly Technical Progress Report: October-December 2005

Description: Mechanically alloyed oxide dispersion strengthened (ODS) Fe-Cr-Al alloy thin walled tubes and sheets, produced via powder processing and consolidation methodologies, are promising materials for eventual use at temperatures up to 1200 C in the power generation industry, far above the temperature capabilities of conventional alloys. Target end-uses range from gas turbine combustor liners to high aspect ratio (L/D) heat exchanger tubes. Grain boundary creep processes at service temperatures, parti… more
Date: April 10, 2006
Creator: Kad, Bimal K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Metal Interconnects for Solid Oxide Fuel Cell Power Systems

Description: Interconnect development is identified by the US Department of energy as a key technical area requiring focused research to meet the performance and cost goals under the Solid State Energy Conversion Alliance initiative. In the Phase I SECA Core Technology Program, Ceramatec investigated a commercial ferritic stainless steel composition for oxidation resistance properties by measuring the weight gain when exposed to air at the fuel cell operating temperature. A pre-treatment process that result… more
Date: April 1, 2006
Creator: Elangovan, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interfacial Reduction-Oxidation Mechanisms Governing Fate and Transport of Contaminants in the Vadose Zone

Description: The mobility of many contaminants is redox sensitive and thus related to the reduction oxidation characteristics of the environment. Immobilization of certain contaminants (e.g., chromium, uranium, and technetium) can be achieved by reducing the contaminant. One remediation approach to achieving this is the application of diluted hydrogen sulfide gas mixtures, which may have particular value in vadose zone applications. Previous work has shown this approach to be viable for Cr(VI) remediation o… more
Date: June 1, 2006
Creator: Thornton, Edward C.; Deng, Baolin; Jurisson, Silvia Sabine & Terry, Jeff
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-Performance Corrosion-Resistant Iron-Based Amorphous Metals - The Effects of Composition, Structure and Environment: Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4

Description: Several Fe-based amorphous metal formulations have been identified that appear to have corrosion resistance comparable to (or better than) that of Ni-based Alloy C-22 (UNS No. N06022), based on measurements of breakdown potential and corrosion rate in seawater. Both chromium (Cr) and molybdenum (Mo) provide corrosion resistance, boron (B) enables glass formation, and rare earths such as yttrium (Y) lower critical cooling rate (CCR). SAM2X5 (Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.… more
Date: October 20, 2006
Creator: Farmer, J; Haslam, J; Day, S; Lian, T; Saw, C; Hailey, P et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Elucidating the Molecular Basis and Regulation of Chromium (VI) Reduction by Shewanella oneidensis MR-1 Using Biochemical, Genomic, and Proteomic Approaches

Description: Although microbial metal reduction has been investigated intensively from physiological and biochemical perspectives, little is known about the genetic basis and regulatory mechanisms underlying the ability of certain bacteria to transform, detoxify, or immobilize a wide array of heavy metals contaminating DOE-relevant environments. The major goal of this work is to elucidate the molecular components comprising the chromium(VI) response pathway, with an emphasis on components involved in Cr(VI)… more
Date: October 30, 2006
Creator: Hettich, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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