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The Solubility of Oxygen in Uranyl Sulphate Solutions at Elevated Temperatures

Description: Abstract: "The solubility of oxygen in uranyl sulphate solutions and in water at 212, 275, and 325 F, and at oxygen partial pressures up to 1500 psia was investigated. The results are presented in tabular and graphic form. The solubility is proportional to the partial pressure of oxygen. The ratio of solubility in the uranyl sulphate solution to solubility in water at the same temperature and pressure is a function of the concentration of the salt in solution."
Date: June 10, 1953
Creator: Pray, H. A. & Stephan, Elmer F.
Partner: UNT Libraries Government Documents Department

Long term biosustainability in a high energy, low diversity crustal biome

Description: Geochemical, microbiological, and molecular analyses of alkaline saline groundwater at 2.8 kilometers depth in Archaean metabasalt revealed a microbial biome dominated by a single phylotype affiliated with thermophilic sulfate reducers belonging to Firmicutes. These sulfate reducers were sustained by geologically produced sulfate and hydrogen at concentrations sufficient to maintain activities for millions of years with no apparent reliance on photosynthetically derived substrates.
Date: October 1, 2006
Creator: Lin, L-H.; Wang, P-L.; Rumble, D.; Lippmann-Pipke, J.; SherwoodLollar, B.; Boice, E. et al.
Partner: UNT Libraries Government Documents Department

Formation of Pyromorphite in Anglesite-Hydroxyapatite Suspensions Under Varying pH Conditions

Description: Addition of phosphate to lead [Pb(ll)l-cOntarninated soil to immobilize soil Pb by formation of pyromorphite has been proposed as an alternative remediation technique. Lead sulfate (PbS04, anglesite), a Pb-bearing form found in contaminated soils and wastes, was reacted with a synthetic phosphate mineral, hydroxyapa$te [Ca5(PO& OH], under constant pH (PH 2-7) and simulated gastric pH conditions (PH varied from 2 to 7 within 30 rein) to assess the effects of reaction kinetics on the formation rate of chloropyromorphite and the volubility of Pb. Under constant pH condition, complete transformation of anglesite to chloropyromorphite, [Pb5(PO&Cl], was obtained at pH 4 and pH 5. At pH 6 and pH 7, the newly formed chloropyromorphite precipitated on the surface of undissolved apatite, The coverage of the apatite surface may reduce apatite dissolution fate and the transformation rate of Pb from anglesite to"chloropyromorphite. Increasing the P/Pb ratio increased the transformation rate, but anglesite was still present after a' 120-min reaction time. in the dynamic pH system, the added apatite was rapidly dissolved at the initial low pH, and complete transformation of anglesite to chloropyromorphite was obtained within 25 min., The soluble Pb level was controlled by the volubility of chloropyromorphite during the entire reaction process. These results demonstrate the effect of reaction kinetics on the formation rate of chloropyromorphite and the mechanisms controlling the solubilization of Pb in the anglesite-apatite system. Furthermore, they illustrate that a complete transformation of ingested anglesite to chloropyromorphite can be achieved. under gastrointestinal tract pH conditions if sufficient phosphate is provided.
Date: October 14, 1998
Creator: Ryan, J.A. & Zhang, P.
Partner: UNT Libraries Government Documents Department

Chemical Engineering Division Environmental Chemistry Annual Report: July 1975-June 1976

Description: The chemistry of airborne particulate matter is being investigated by means of laboratory and field studies. Experiments were conducted using the flow reactor to identify the reaction conditions under which detectable amounts of sulfate particles could be formed under gaseous sulfur dioxide. A procedure was developed for the analysis of acidic and neutral ammonium sulfate in filter-collected samples of atmospheric particulate matter.
Date: 1976?
Creator: Cunningham, P. T.; Kumar, R.; Holt, B. D.; Hubble, B. R.; Johnson, S. A.; Nielsen, E. et al.
Partner: UNT Libraries Government Documents Department

Uranium Peroxide

Description: It was desired to investigate the precipitation of UO{sub 4} in acid solution, in order to determine the suitability of this reaction for use in the purification of uranium. A series of tests was performed to establish the conditions for precipitation of UO{sub 4}. It was found that uranium could be completely precipitated from pure uranyl sulfate solution at a pH of 2.5 to 3.5, with only silght excess of H{sub 2}O{sub 2}. The presence of sodium sulfate interferred with complete precipitation. It was established that vanadium was preferentially oxidized, when present.
Date: April 14, 1947
Creator: Brimm, E. O., Dr. & Nohr, P.
Partner: UNT Libraries Government Documents Department


Description: The study of meteorite Murray has been reported in previous Quarterly Reports. This report gives further results with Murray, and information on another meteorite, Orgueil. A sample of Orgueil was sent from the Museum National d Histoire Naturelle, Paris. It fell in several pieces over an area of 2 square miles near Orgueil, France, in 1864. The elemental analysis of this meteorite is shown in Table 1. They extracted a 10.07-g sample of this meteorite with water, using the same procedure as that for Murray. The water extracted 1.32 g, which is at least twice as much material as was water-extracted from Murray. The elemental analysis of the water extract is given in Table II and its uv spectrum is shown in Figure 1. From an x-ray diffraction pattern it was determined that the water extract contained mostly MgSO{sub 4} {center_dot} 6H{sub 2}O with some calcium sulfate. Their spectrum (Figure 2) shows a strong SO{sub 4} band at 1100 cm{sup -1}, = strong H{sub 2}O bands at 1650 cm{sup -1} and 3200-3600 cm{sup -1}, and some unidentified peaks at 2300, 1400, and 980 cm{sup -1}. The approximately 8 g of Orgueil left after the water extraction was then extracted with purified chloroform. Approximately 50 mg of yellow material was extracted. Its uv spectrum is shown in Figure 3 and is identical to the spectrum of elemental sulfur. Whatever else may be extracted from the meteorites by organic solvents, the uv spectra show only sulfur.
Date: June 29, 1961
Partner: UNT Libraries Government Documents Department


Description: Loop L-2-19 operated in HB-2 of the WTR for 1148.9 hours of circulation and 2705 Mwhr of LITR operation. The solution contained 0.17 m enriched UO/sub 2/ SO/sub 4/, 0.02 m CuSO/sub 4/, 0.12 m excess H/sub 2/SO/sub 4/, and 0.20 m Li/sub 2/SO/sub 4/ in H /.sub 2/O, The main stream was 280 deg C and the pressurizer 295 deg C. There was no unusual difficulty during loop operation. A revised loop sample procedure gave better flushing of the sample lines. Four valves failed due to severe corrosion and fracturing of the 420 SS stems. 1-131 was not detected in a sample of gas taken from the gas hold-up tank. The run was terminated when the circulating pump failed. (auth)
Date: June 19, 1958
Creator: Lorenz, R.A.
Partner: UNT Libraries Government Documents Department


Description: A study was made of the distribution of Ag, Au, Bt, and Pd in the residues from an extraction process in which purified UO/sub 2/(NO/sub 3/)/sub 2/ is prepared from a pitchblende ore. The residues studied were the gangue Pb cake, the BaSO/sub 4/ cake, the filtrate boildown cake, the raffinate cake, and the purified UO/sub 2/(NO/sub 3/)/sub 2/. Samples representing three different batches of ore were used. The following conclusions were reached: (1) neither Ag nor Pd are present in the ore in significant quantities; (2) approximately 30 ppm of Au (based on U content) is present, of which 90% was found in the residue (gangue Pb cake) from the initial co-precipitation step; this residue contains gangue, PbSO/sub 4/, RaSO/sub 4/, and other insoluble sulfates; (3) the ore contains 15 ppm of Pt, which is distributed in an extremely varying manner in the residues leaving the process. (W. L.H.)
Date: April 1, 1946
Creator: Shearer, R.W.
Partner: UNT Libraries Government Documents Department

Mercury in Fish from a Sulfate-Amended Wetland Mesocosm

Description: This study used an experimental model of a constructed wetland to evaluate the risk of mercury methylation when the soil is amended with sulfate. The model was planted with Schoenoplectus californicus, and the sediments were varied during construction to provide a control and two levels of sulfate treatment.
Date: May 29, 2003
Creator: Harmon, S.M.
Partner: UNT Libraries Government Documents Department


Description: In this work a technique was described to study the repassivation of bare metal surfaces. The advantage of this approach over other techniques is the ease with which multiple repassivation events can be studied. The repassivation rate of aluminum was found to depend on the anion in solution. Repassivation rates are higher for aluminum in phosphate and sulfate solutions compared to borate. It is possible that borate may interact more strongly than sulfate or phosphate on the bare aluminum surface blocking the diffusion of oxygen or changing the rate of repassivation.
Date: September 1, 1977
Partner: UNT Libraries Government Documents Department

An investigation of the effect of sulfate on cloud microphysics using a chemistry/transport model

Description: Here the authors have used the output of a chemistry/transport model to identify a situation in which sulfate aerosol from industrial sources may be expected to exert a strong influence on cloud microphysical and radiative properties in an oceanic area that is well displaced from source regions. Pertinent cloud microphysical properties (optical depth and cloud drop radius) are inferred from radiance data obtained from satellite remote sensing. Comparison of these quantities in situations where the model indicates the presence or absence of industrial sulfate has allowed identification of the expected signature of one aerosol indirect effect--an increase in droplet number concentration and concomitant decrease in droplet radii, on a synoptic scale. Although the information obtained on changes in cloud optical depth is too meager to draw conclusions regarding radiative forcing, there is no doubt that the cloud microphysical properties are influenced by the incursion of continental sulfate aerosol in a way that is consistent with that expected by the Twomey indirect forcing mechanism.
Date: January 14, 2001
Creator: Wei, H.D.; Green, R.; Schwartz, S.E. & Benkovitz, C.M.
Partner: UNT Libraries Government Documents Department

Evaluation of Brine Desulfating Process As Applied To Desalination Phase 1

Description: Report issued by the Office of Saline Water over studies conducted on the desulfating process at desalination plants. As stated in the introduction, "the explicit purpose of this study is to determine whether or not application of the feed-water desulfating process to the feed to a desalting plant will reduce the overall cost of desalted water" (p. 1). This report includes tables, and illustrations.
Date: October 1967
Creator: Ennis, Charles E.; Gelblum, G. P. & Pechenick, William
Partner: UNT Libraries Government Documents Department


Description: This report describes work done in the pilot plant at Msllinckrodt toward development of a recovery process for U in BaSO/sub 4/ take. The investigation involved examination of chemical leaching problems, and testing of filtration equipment for recovery of the leached cake. Several additional problems uncovered during the work were introduction of the BaSO/sub 4/ cake into a slurry, settling of heavy fines in process equipment, and forming of the BaS0/ sub 4/ slurry. (auth)
Date: May 1, 1953
Creator: Kirby, A.M.
Partner: UNT Libraries Government Documents Department

Feedbacks between hydrological heterogeneity and bioremediation induced biogeochemical transformations

Description: For guiding optimal design and interpretation of in-situ treatments that strongly perturb subsurface systems, knowledge about the spatial and temporal patterns of mass transport and reaction intensities are important. Here, a procedure was developed and applied to time-lapse concentrations of a conservative tracer (bromide), an injected amendment (acetate) and reactive species (iron(II), uranium(VI) and sulfate) associated with two field scale biostimulation experiments, which were conducted successively at the same field location over two years. The procedure is based on a temporal moment analysis approach that relies on a streamtube approximation. The study shows that biostimulated reactions can be considerably influenced by subsurface hydrological and geochemical heterogeneities: the delivery of bromide and acetate and the intensity of the sulfate reduction is interpreted to be predominantly driven by the hydrological heterogeneity, while the intensity of the iron reduction is interpreted to be primarily controlled by the geochemical heterogeneity. The intensity of the uranium(VI) reduction appears to be impacted by both the hydrological and geochemical heterogeneity. Finally, the study documents the existence of feedbacks between hydrological heterogeneity and remediation-induced biogeochemical transformations at the field scale, particularly the development of precipitates that may cause clogging and flow rerouting.
Date: April 15, 2009
Creator: Englert, A.; Hubbard, S.S.; Williams, K.H.; Li, L. & Steefel, C.I.
Partner: UNT Libraries Government Documents Department


Description: Corrosion of iron-base alloys at 982 C (1800 F) by coal char is observed and the phase morphologies discussed. No sulfidation was observed at 50 hours exposure. After 100 hours, internal aluminum-rich sulfides were observed along with thick outer scales of iron oxide. The species causing the high-temperature induced corrosion are probably sulfides and sulfates, present in most coal chars. Possible mechanisms for the corrosion are also discussed.
Date: October 1, 1977
Creator: Gordon, B.A. & Nagarajan, V.
Partner: UNT Libraries Government Documents Department


Description: Both the study and the use of extractions with highmolecular-weight amines (including quaternary ammoniums) in organic solution are increasing extensively. While equilibria have been measured in the extraction of an increasing range of acids and Aetal ions, a difficulty remains unresolved in that the amine concentration powerdependence of extraction often indicates a different stoichiometry of the complex existing in the organic phase than do limiting loading and other considerations. Nevertheless, amine extraction serves as a useful tool in studying complexes formed in aqueous systems. Process applications have progressed especially in nitrate and chioride systems, in addition to the sulfate systems first emphasized. Systematic surveys, together with information accruing from process development, have extended the ranges of extractions that can be correlated in usefully generalized patterns, which in turn should accelerate the development of new applications. However, many more areas remain to be surveyed before the many pertinent variables will have been covered. New amines of all classes have become available at commercial, development, or researchsample levels, while a few previously promising amines have become less available. Descriptions and current sources are reviewed. (auth)
Date: November 26, 1963
Creator: Coleman, C.F.
Partner: UNT Libraries Government Documents Department