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Sampling Instruction: Investigation of Hexavalent Chromium Flux to Groundwater at the 100-C-7:1 Excavation Site

Description: Several types of data are needed to assess the flux of Cr(VI) from the excavation into the groundwater. As described in this plan, these data include (1) temporal Cr(VI) data in the shallow groundwater beneath the pit; (2) hydrologic data to interpret groundwater flow and contaminant transport; (3) hydraulic gradient data; and (4) as a contingency action if necessary, vertical profiling of Cr(VI) concentrations in the shallow aquifer beyond the depth possible with aquifer tubes.
Date: May 1, 2012
Creator: Truex, Michael J. & Vermeul, Vincent R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Description of Work for Drilling at the 183-DR Site in Support of the In Situ Gaseous Reduction Test

Description: In Situ Gaseous Reduction is a technology currently being developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. Prior work suggests that a candidate for application of this approach is the 183-DR site at Hanford. However, deep vadose zone drilling is needed to verify the presence of a hexavalent chromium source and to determine the concentration levels and spatial distribution of contamination. This document presents the requirements associated with dri… more
Date: June 26, 2000
Creator: Thornton, Edward C.; Olsen, Khris B. & Schalla, Ronald
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrolytic Polymerization of Chromium (III) Hydroxides in the Aquatic Environment

Description: Products of hydrolytic polymerization of Cr(III) hydroxide were investigated in Milli-Q water and in natural water matrices. Products were first fractionated on Sephadex column using eluents of increasing strength. Ion chromatography (IC) with UV detection at 436 nm was then used to separate the ionic species.
Date: December 1991
Creator: Mbamalu, Godwin E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Gas Plated Coatings on Metals and Alloys : Progress Report No. 6 and Final Report

Description: The object of the work performed under this contract was to investigate the possibility of gas plating copper base metal with (a) pure chromium metal from chromium hexacarbonyl vapor; (b) chromium-nickel plating from a mixture of chromium hexacarbonyl and nickel tetracarbonyl. The object of the work performed during the final month was to confirm the fact that the gas plating of chromium metal and chromium-nickel laminates free from nitrides, oxides and carbides was practical.
Date: June 5, 1953
Creator: Nack, Herman; Bulloff, Jack J. & Whitacre, John R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Differential isotopic fractionation during Cr(VI) reduction by an aquifer-derived bacterium under arobic versus denitrifying conditions

Description: We studied Cr isotopic fractionation during Cr(VI) reduction by Pseudomonas stutzeri strain RCH2. Despite the fact that strain RCH2 reduces Cr(VI) co-metabolically under both aerobic and denitrifying conditions and at similar specific rates, fractionation was markedly different under these two conditions (ε ~2� aerobically and ~0.4� under denitrifying conditions).
Date: February 1, 2012
Creator: Han, R.; Qin, L.; Brown, S. T.; Christensen, J. N. & Beller, H. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chromium isotopes as indicators of hexavalent chromium reduction

Description: This is the final report for a university research project which advanced development of a new technology for identifying chemical reduction of hexavalent chromium contamination in groundwater systems. Reduction renders mobile and toxic hexavalent chromium immobile and less toxic. The new method uses stable isotope ratio measurements, which are made using multicollector ICP-mass spectrometry. The main objectives of this project were completed during the project period and two peer-reviewed arti… more
Date: March 20, 2012
Creator: Johnson, Thomas M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of phosphates to reduce slag penetration in Cr2O3-based refractories

Description: A high-chromium refractory material that provides improved resistance to coal slag penetration is presented. The refractory mixture comprises a blend of chromium oxide, aluminum oxide and phosphates. The refractory mixture may be blended with an aggregate and cured. In addition a phosphorous oxide may be blended with chromium oxide and aluminum oxide and additionally an aggregate. The refractory mixture reduces the rate of coal slag penetration into the surface of the cured refractory.
Date: November 9, 2004
Creator: Kwong, Kyei-Sing; Dogan, Cynthia P.; Bennett, James P.; Chinn, Richard E. & Petty, Arthur V.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Ion Chromatography of Soluble Cr(III) and Cr(VI)

Description: Ion chromatography coupled with a conductivity detector was used to investigate the analysis of Cr(III) and Cr(VI) in aqueous samples. An IC methodology for Cr(III) was developed using a cation column and an eluent containing tartaric acid, ethylenediamine, and acetonitrile at pH 2.9. The detection limit of this method can reach 0.1 ppm level with good precision. Several operational parameters were evaluated during the regular use of the method. Comparison of the IC method with AA method showed… more
Date: August 1988
Creator: Huang, Julie Shiong-Jiun
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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THE ABSOLUTE ABUNDANCE OF THE CHROMIUM ISOTOPES IN SOME SECONDARY MINERALS

Description: Isotopic assays have been made on the Cr in samples from 14 different chrominiferous minerals from different geographic and meteoritic sources. The results of the assays indicate that it is not possible to state unequivocally that variations in isotopic composition have been observed. (auth)
Date: March 14, 1962
Creator: Svec, H. J.; Flesch, G. D. & Capellen, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microbial community changes during sustained Cr(VI) reduction at the 100H site in Hanford, WA

Description: Hexavalent Chromium is a widespread contaminant found in soil, sediment, and groundwater. In order to stimulate microbially-mediated reduction of Cr(VI), a poly-lactate compound (HRC) was injected into the Chromium-contaminated aquifer at the Hanford (WA) 100H site in 2004. Cr(VI) concentrations rapidly declined to below the detection limit and remained so for more than three years after injection. Based on the results of the bacterial community composition using high-density DNA 16S rRNA gene … more
Date: May 17, 2010
Creator: Chakraborty, Romy; Brodie, Eoin L; Faybishenko, Boris; Piceno, Yvette M; Tom, Lauren; Choudhuri, Swati et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Immunotoxicity of Chromium Contaminated Soil in the Earthworm, Lumbricus Terrestris

Description: Objective was to assess the toxicity of chromium (Cr) contaminated soil (CS) using the earthworm Lumbricus terrestris. Specific aims were to determine: (1) survival (LC50); .(2) immunotoxicity as indicated by lysozyme activity, coelomocyte counts, secretory (SR) and erythrocyte rosette (ER) formation, and phagocytosis; and (3) compare effects of CS exposure with those of Cr spiked artificial soil (AS) . CS Cr concentration was 8.78 mg/g with 98.2% being Cr^3+ and 1.8% being Cr^6+. Using 14 d AS… more
Date: May 1993
Creator: Mohammadian, Gholamreza
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Determination of Corrosion Products and Additives in Homogenous Reactor Fuel II. Polarographic Determination of Chromium

Description: A satisfactory ion-exchange-polarographic method was developed for the determination of either chromium(VI) or total chromium in Homogeneous Reactor fuels. Total chromium is determined as chromium (VI) , i.e., chromate, and in the same way as is chromium(VI), after chromium in the lower valence states is oxidized to chromate by potassium permanganate. Chromate is separated from all interfering metal ions in the fuel by ion exchange on a Dowex 50 resin column. The Chromate in the effluent is det… more
Date: September 13, 1955
Creator: Horton, A. D. & Thomason, P. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization Activities Conducted at the 183-DR Site in Support of an In Situ Gaseous Reduction Demonstration

Description: In Situ Gaseous Reduction (ISGR) is a technology developed by DOE for the remediation of soil waste sites contaminated with hexavalent chromium. This document presents information associated with characterization activities conducted at the 183-DR site at Hanford, which is associated with a significant groundwater contaminant plume and was formerly a water treatment facility that utilized chromate as a corrosion inhibitor. Geotechnical and chemical data were collected during the excavation of t… more
Date: March 30, 2001
Creator: Thornton, Edward C.; Gilmore, Tyler J.; Olsen, Khris B.; Schalla, Ronald & Cantrell, Kirk J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analytical representation of mechanical properties data for 2 1/4 Cr--1 Mo steel

Description: An extensive program has been underway at the Oak Ridge National Laboratory (ORNL) for the last five years to develop analytical representations for various mechanical properties of 2 1/4 Cr--1 Mo steel. This program includes an evaluation of tensile, creep, fatigue, creep-fatigue, crack growth, and toughness data for this material. Data were collected from a variety of sources and stored in an existing computerized Data Storage and Retrieval System (DSRS) to facilitate analysis. Most of these … more
Date: January 1, 1978
Creator: Booker, M. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A TRACER STUDY OF THE TRANSPORT OF CHROMIUM IN FLUORIDE FUEL SYSTEMS

Description: An experimental study was made of the mass transport of chromium in poly- thermal Inconel-fluoride fuel systems. The transport of chromium was followed by toe technique of adding radioactive Cr/sup 51/ to the system as either CrF/sub 2/ , in the salt or as elemental chromium in the solid phase. The rates of diffusion of chromium in Inconel at 600, 700, 800, and 900 deg C were determined by an electropolishing technique. Polythermal studies were carried out by three methods, tilting capsules, th… more
Date: June 18, 1957
Creator: Price, Robert B.; Sunderman, Duane N.; Pobereskin, Meyer & Calkins, George D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Enhanced High Temperature Corrosion Resistance in Advanced Fossil Energy Systems by Nano-Passive Layer Formation

Description: Due to their excellent corrosion resistance, iron aluminum alloys are currently being considered for use as weld claddings in fossil fuel fired power plants. The susceptibility to hydrogen cracking of these alloys at higher aluminum concentrations has highlighted the need for research into the effect of chromium additions on the corrosion resistance of lower aluminum alloys. In the present work, three iron aluminum alloys were exposed to simulated coal combustion environments at 500 C and 700 C… more
Date: June 14, 2007
Creator: Marder, Arnold R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study to optimize Cr-Mo steels to resist hydrogen and temper embrittlement. Quarterly report No. 6, November 15, 1979-February 15, 1980

Description: A modified test technique has been developed in this program to overcome difficulties in assessing the hydrogen embrittlement susceptibility of low strength 2 1/4 Cr-1 Mo steels. One steel sample was tempered to a range of strength levels and evaluated using the new technique. The results, showing a lower strength level for which hydrogen embrittlement susceptibility can be assessed in a 446 KPa H/sub 2/S environment, are presented in this report. A review of the restructuring of the program is… more
Date: July 28, 1980
Creator: Shaw, B.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanical properties of modified 9 Cr--1 Mo steel

Description: This program deals with mechanical property evaluation of 24 experimental and 1 large commercial heat of 9 Cr--1 Mo steel developed by Combustion Engineering. The mechanical properties evaluation involves the following tests: Charpy impact test to determine the ductile brittle transition temperature, tensile tests at room temperature and 649/sup 0/C, and screening creep and creep-rupture tests at 593 and 649/sup 0/C.
Date: January 1, 1978
Creator: Sikka, V.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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