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Terrestrial fate of coal-liquid constituents: behavior of alkyl anilines in soil

Description: The low molecular weight aromatic amines (anilines) are important water soluble constituents of coal liquids. The impact of anilines released to the terrestrial environment will largely depend on their mobility and persistence. Studies were conducted to investigate those processes governing the mobility and persistence of the alkylanilines, namely, soil sorption and chemical/microbial degradation. Soil sorption measurements were conducted on aniline and several methyl substituted anilines on A … more
Date: July 1, 1982
Creator: Felice, L. J.; Zachara, J. M. & Rogers, J. E.
Partner: UNT Libraries Government Documents Department
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Effects of mineralogy on sorption of strontium and cesium onto Calico Hills Tuff

Description: The sorption properties of tuff formations at the proposed site for the high-level nuclear waste repository at Yucca Mountain, Nevada, have been extensively studied. Sorption and desorption measurements were made of strontium and cesium onto clinoptilolite and Calico Hills Tuff. The object was to see whether there was a correlation between sorption of strontium and cesium onto Calico Hills Tuff and the sorption of strontium and cesium onto clinoptilolite based on the content of clinoptilolite i… more
Date: April 1, 1990
Creator: Meyer, R. E.; Arnold, W. D.; Case, F. I.; O`Kelley, G. D. & Land, J. F.
Partner: UNT Libraries Government Documents Department
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Sorption Charecterization of Radonuclides on Clays in Yucca Mountain Alluvium

Description: Sorption of {sup 237}Np(V) and {sup 233}U(VI) was measured on clays separated from Yucca Mountain alluvium as a function of solution pH and aqueous actinide concentrations. The results indicate that sorption of U and Np on the separated clay fraction depends strongly on solution pH. Np sorption on clays increases slowly with increasing pH from 3 to 7. Above pH 7, Np sorption on clays increases rapidly up to a pH of about 10. On the other hand, U sorption on clays reaches it maximum at a pH of a… more
Date: March 17, 2006
Creator: Ding, M.; Reimus, P. W.; Chipera, S. & Scism, C.
Partner: UNT Libraries Government Documents Department
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Dependence of liquefaction behavior on coal characteristics. Part V. Penetration of solvent vapor into coal particles. Final technical report, March 1981-February 1984

Description: The investigation of the sorption of solvent vapor into high volatile bituminous coal at temperatures up to 175/sup 0/C indicates that the solvent weight gain involves a complex coupling of several phenomena including adsorption, sorption into the coal matrix, capillary condensation and extraction into the condensed vapor phase. It appears that the sorption in untreated coal is dominated by capillary condensation induced by solvent extraction. As a result, an equilibrium state is not attainable… more
Date: April 1, 1984
Creator: Hsieh, S. T. & Duda, J. L.
Partner: UNT Libraries Government Documents Department
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Permeability changes in coal resulting from gas desorption

Description: During this quarter, work was continued on measuring the methane sorption capacity of dispersed organic matter in gas shales and maceral concentrates derived from a Kentucky coal. Although previous results have demonstrated that the microbalance technique is successful in generating sorption isotherm curves, the accuracy of the technique has not been well established. The only previous test that allowed a comparison between gravimetric data and volumetric data showed a significant discrepancy w… more
Date: January 1, 1992
Creator: Levine, J. R. & Johnson, P. M.
Partner: UNT Libraries Government Documents Department
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Markov models and the ensemble Kalman filter for estimation of sorption rates.

Description: Non-equilibrium sorption of contaminants in ground water systems is examined from the perspective of sorption rate estimation. A previously developed Markov transition probability model for solute transport is used in conjunction with a new conditional probability-based model of the sorption and desorption rates based on breakthrough curve data. Two models for prediction of spatially varying sorption and desorption rates along a one-dimensional streamline are developed. These models are a Marko… more
Date: September 1, 2007
Creator: Vugrin, Eric D.; McKenna, Sean Andrew & Vugrin, Kay White
Partner: UNT Libraries Government Documents Department
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Compositional and Structural Control on Anion Sorption Capability of Layered Double Hydroxides (LDHS)

Description: Layered double hydroxides (LDHs) have shown great promise as anion getters. In this paper, we demonstrate that the sorption capability of a LDH for a specific oxyanion can be greatly increased by appropriately manipulating material composition and structure. A large set of LDH materials have been synthesized with various combinations of metal cations, interlayer anions, and the molar ratios of divalent cation M(II) to trivalent cation M(III). The synthesized materials have then been tested syst… more
Date: March 16, 2006
Creator: Wang, Y. & Gao, H.
Partner: UNT Libraries Government Documents Department
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Desorption Behavior of Trichloroethene and Tetrachloroethene in u.s. Department of Energy Savannah River Site Unconfined Aquifer Sediments

Description: Sorption is governed by the physico-chemical processes that partition solutes between the aqueous and solid phases in aquifers. For environmental systems, a linear equilibrium relationship between the amount of contaminant in the alternative phases is often assumed. In this traditional approach, the distribution coefficient, or K{sub d}, is a ratio of contaminant associated with the solid phase to the contaminant in the water phase. Recent scientific literature has documented time-dependant beh… more
Date: January 10, 2007
Creator: Vangelas, K.; Robert G.; Riley, R.; James E.; Szecsody, J.; Mitroshkov, A. V. et al.
Partner: UNT Libraries Government Documents Department
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Surface Complexation Model for Strontium Sorption to Amorphous Silica and Goethite

Description: Strontium sorption to amorphous silica and goethite was measured as a function of pH and dissolved strontium and carbonate concentrations at 25 C. Strontium sorption gradually increases from 0 to 100% from pH 6 to 10 for both phases and requires multiple outer-sphere surface complexes to fit the data. All data are modeled using the triple layer model and the site-occupancy standard state; unless stated otherwise all strontium complexes are mononuclear. Strontium sorption to amorphous silica in … more
Date: November 30, 2007
Creator: Carroll, S.; Robers, S.; Criscenti, L. & O'Day, P.
Partner: UNT Libraries Government Documents Department
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Thermodynamics of the solvent swelling of coal

Description: Sorption of pyridine by the pyridine-extracts of three premium Argonne coals was studied at several relative vapor pressures at 50{degree}C and 70{degree}C. The amount of pyridine sorbed by each extract increases linearly with pyridine vapor pressure. Heat of dilution were calculated from the slopes of the straight-line portions of the curves. In a related experiment, the pyridine sorption isotherms of the pyridine-extract, pyridine-insoluble residue, and the whole coal were determined at 50{de… more
Date: January 1, 1990
Creator: Green, T.K.
Partner: UNT Libraries Government Documents Department
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Radionuclide migration laboratory studies for validation of batch sorption data

Description: Advective and diffusive migration experiments (within the Dynamic Transport Column Experiments and Diffusion Studies of the Yucca Mountain Site Characterization Project) involve utilizing crushed material, intact, and fractured tuff in order to test and improve (if necessary) transport models by experimentally observing the migration of sorbing and non-sorbing radionuclides on a laboratory scale. Performing a validation of the sorption data obtained with batch techniques (within the Batch Sorpt… more
Date: December 31, 1991
Creator: Triay, I. R.; Mitchell, A. J. & Ott, M. A.
Partner: UNT Libraries Government Documents Department
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The Effect of Organic Ligands on the Sorption of Neodymium, Gadolinium and Uranium onto Nontronite and Goethite

Description: The sorption of the rare earth elements (REE) Nd(III) and Gd(III) onto goethite in the presence of Suwannee River fulvic acid in 0.1 m NaCl solutions at 25 ºC was investigated quantitatively. The experiments involved batch titrations whereby the concentrations of REE and/or fulvic acid remaining in solution were determined as a function of pH. In the absence of fulvic acid, removal of REE from solution is enhanced in the presence of goethite over the pH range from 6 to 8, compared to the unary … more
Date: June 12, 2007
Creator: Wood, Scott A.
Partner: UNT Libraries Government Documents Department
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Anionic sorbents for arsenic and technetium species.

Description: Two sorbents, zirconium coated zeolite and magnesium hydroxide, were tested for their effectiveness in removing arsenic from Albuquerque municipal water. Results for the zirconium coated zeolite indicate that phosphate present in the water interfered with the sorption of arsenic. Additionally, there was a large quantity of iron and copper present in the water, corrosion products from the piping system, which may have interfered with the uptake of arsenic by the sorbent. Magnesium hydroxide has … more
Date: September 1, 2003
Creator: Lucero, Daniel A.; Moore, Robert Charles; Bontchev, Ranko Panayotov; Hasan, Ahmed Ali Mohamed; Zhao, Hongting; Salas, Fred Manuel et al.
Partner: UNT Libraries Government Documents Department
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GEOQUÌMICO : an interactive tool for comparing sorption conceptual models (surface complexation modeling verus K[D]).

Description: Within reactive geochemical transport, several conceptual models exist for simulating sorption processes in the subsurface. Historically, the K{sub D} approach has been the method of choice due to ease of implementation within a reactive transport model and straightforward comparison with experimental data. However, for modeling complex sorption phenomenon (e.g. sorption of radionuclides onto mineral surfaces), this approach does not systematically account for variations in location, time, or c… more
Date: November 1, 2007
Creator: Hammond, Glenn E. (Pacific Northwest National Laboratory, Richland, WA) & Cygan, Randall Timothy
Partner: UNT Libraries Government Documents Department
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Effects of Hanford high-level waste components on sorption of cobalt, strontium, neptunium, plutonium, and americium on Hanford sediments

Description: To judge the feasibility of continued storage of high-level waste solutions in existing tanks, effects of chemical waste components on the sorption of hazardous radioelements were determined. Experiments identified the effects of 12 Hanford high-level waste-solution components on the sorption of cobalt, strontium, neptunium, plutonium, and americium on 3 Hanford 200 Area sediments. The degree of sorption of strontium, neptunium, plutonium, and americium on two Hanford sediments was then quantif… more
Date: March 1, 1983
Creator: Delegard, C H & Barney, G S
Partner: UNT Libraries Government Documents Department
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Characterization of U(VI) Sorption-Desorption Processes and Model Upscaling

Description: The objectives of the overall collaborative EMSP effort (with which this project is associated) were to characterize sorption and desorption processes of U(VI) on pristine and contaminated Hanford sediments over a range of sediment facies and materials properties and to relate such characterization both to fundamental molecular-scale understanding and field-scale models of geochemistry and mass transfer. The research was intended to provide new insights on the mechanisms of U(VI) retardation at… more
Date: October 12, 2006
Creator: Bai, Jing; Dong, Wenming & Ball, William P.
Partner: UNT Libraries Government Documents Department
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SORPTION OF URANIUM ON ZIRCONIUM OXIDE

Description: The sorption of the ions of uranium, copper, and nickel on hydrous zirconium oxide was investigated at temperatures from 25 to 250 deg C. The experiments were performed by equilibrating 5 ml of the test solution with 0.5 g of zirconium oxide in a titanium autoclave, which was heated by means of a rocking furnace. The sorption of uranium was affected by characteristics of the zirconium oxide, temperatare of equilibration, and concentrations of uranium and of free acid in the uranyl sulfate solut… more
Date: September 13, 1961
Creator: Goldstein, G.
Partner: UNT Libraries Government Documents Department
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Engineered Natural Geosorbents for In-Situ Immobilization of DNAPLs and Heavy Metals

Description: The report summarizes work progress from 9/15/02-12/31/2003 for the project. Progresses in these five specific areas of investigation are summarized: (1) Production of engineered natural geosorbents (ENGs); (2) Characterization of the physicochemical properties of ENGs; (3) Characterization of the sorption and desorption properties of ENGs for TCE, PCE; (4) Characterization of the sorption and desorption properties of ENGs for heavy metals 4a; and (5) Characterization of the competitive sorptio… more
Date: June 1, 2003
Creator: Weber, Walter J.
Partner: UNT Libraries Government Documents Department
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Actinide Sorption in Rainier Mesa Tunnel Waters from the Nevada Test Site

Description: The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. … more
Date: December 17, 2007
Creator: Zhao, P.; Zavarin, M.; Leif, R.; Powell, B.; Singleton, M.; Lindvall, R. et al.
Partner: UNT Libraries Government Documents Department
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