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Refining and Utilization of Georgia Kaolins

Description: From Introduction: "The investigation described in this report was carried on to determine the practicability of applying technical control of clay disperse systems to the refining of kaolins and the utilization of the prepared clay in the manufacture of vitreous china and wall tile."
Date: 1916
Creator: Sproat, Ira E.
Partner: UNT Libraries Government Documents Department

Syllabus of Clay Testing

Description: From Introduction: "One of the many services rendered by the Federal Bureau of Mines is the identification and general examination of ore and mineral samples. This publication describes methods of testing these samples. The object of this publication is to present the testing procedures in general use in the industry up to the point where the checking becomes a quantitative one for particular products."
Date: 1957
Creator: Klinefelter, T. A. & Hamlin, H. P.
Partner: UNT Libraries Government Documents Department

Syllabus of Clay Testing: Part 1

Description: From Introduction: "This presentation (pt. 1) is what might be termed a qualitative syllabus, in that uses only are indicated, no attempt being made to evaluate a clay quantitatively, that is, to grade for particular uses. In part 2, which is to follow, the work will be amplified both qualitatively and quantitatively. In the first, preliminary tests are made to eliminate from consideration all nonclay minerals or clay minerals containing such large amounts of impurities as to render them unfit for normal uses and also to make a broad general classification of the clay minerals into the kaolinite (shales and clays) and montmorillonite groups. In the second step, the main tests, divided into two general headings, ceramic and noncermaic, are detailed."
Date: 1943
Creator: Klinefelter, Theron A.; O'Meara, Robert G.; Gottlieb, Sidney & Truesdell, Glenn C.
Partner: UNT Libraries Government Documents Department

Ochers and Mineral Pigments of the Pacific Northwest : Occurrence, Possible Methods of Preparation, and Testing of Ochers, Siennas, and Colored Clays

Description: From Introduction: "A review is given of the nomenclature, sources, imports, statistics, common methods of preparation, and testing of mineral pigments. A description of the Deer Park-Spokane colored-clay district and the laboratory methods of preparation of these colored clays, ochers, and siennas follows. The following report is merely preliminary in nature, only three months during the summer of 1927 being devoted to the laboratory investigation."
Date: 1929
Creator: Wilson, Hewitt
Partner: UNT Libraries Government Documents Department

Differential Thermal Analysis: Its Application to Clays and Other Aluminous Minerals

Description: Report issued by the Bureau of Mines discussing thermal analysis of clays and aluminous minerals. As stated in the introduction, "the applications and limitations of this method to the study of various clays, bauxites, and aluminous minerals will be discussed in this paper" (p. 1). This report includes tables, illustrations, and photographs.
Date: 1945
Creator: Speil, Sidney; Berkelhamer, Louis H.; Pask, Joseph A. & Davies, Ben
Partner: UNT Libraries Government Documents Department

The suitability of five Denton County clays for use in high school ceramics classes

Description: The purpose of this study is to determine the suitability of five clays from the vicinity of Denton, Texas for use in high-school ceramics classes. The abundance of natural clays in Denton County and throughout the state of Texas, the ease with which clays may be obtained, and the ease with which they may be refined for use provide almost unlimited teaching possibilities in high-school art classes.
Date: August 1949
Creator: Tooley, Martin P.
Partner: UNT Libraries

Stereo soft x-ray microscopy and elemental mapping of hematite and clay suspensions

Description: The spatial arrangements of hematite particles within aqueous soil and clay samples are investigated with soft X-ray microscopy, taking advantage of the elemental contrast at the Fe-L edge around E = 707 eV. In combination with stereo microscopy, information about spatial arrangements are revealed and correlated to electrostatic interactions of the different mixtures. Manipulation of a sample mounted to the microscope is possible and particles added while imaging can be detected.
Date: September 1, 2008
Creator: Gleber, S.-C.; Thieme, J.; Chao, W. & Fischer, P.
Partner: UNT Libraries Government Documents Department

IMPROVED PROCESSES TO REMOVE NAPHTHENIC ACIDS

Description: In the second year of this project, we continued our effort to develop low temperature decarboxylation catalysts and investigate the behavior of these catalysts at different reaction conditions. We conducted a large number of dynamic measurements with crude oil and model compounds to obtain the information at different reaction stages, which was scheduled as the Task2 in our work plan. We developed a novel adsorption method to remove naphthenic acid from crude oil using naturally occurring materials such as clays. Our results show promise as an industrial application. The theoretical modeling proposed several possible reaction pathways and predicted the reactivity depending on the catalysts employed. From all of these studies, we obtained more comprehensive understanding about catalytic decarboxylation and oil upgrading based on the naphthenic acid removal concept.
Date: May 5, 2005
Creator: Zhang, Aihua; Ma, Qisheng & Kangshi Wang, William A. Goddard, Yongchun Tang
Partner: UNT Libraries Government Documents Department

Interpreting Velocities from Heat-Based Flow Sensors by NumericalSimulation

Description: We have carried out numerical simulations of three-dimensional non-isothermal flow around an in situ heat-based flow sensor to investigate how formation heterogeneities can affect the interpretation of ground water flow velocities from this instrument. The flow sensor operates by constant heating of a 0.75 m long, 5 cm diameter cylindrical probe, which contains 30 thermistors in contact with the formation. The temperature evolution at each thermistor can be inverted to obtain an estimate of the ground water flow velocity vector using the standard interpretive method, which assumes that the formation is homogeneous. Analysis of data from heat-based flow sensors installed in a sand aquifer at the Former Fort Ord Army Base near Monterey, California suggested an unexpected component of downward flow. The magnitudes of the vertical velocities were expected to be much less than the horizontal velocities at this site because the sensors were installed just above a clay aquitard. Numerical simulations were conducted to examine how differences in thermal conductivities may lead to spurious indications of vertical flow velocities. We found that a decrease in the thermal conductivity near the bottom of the sensor can perturb the temperature profiles along the instrument in such a manner that analyses assuming homogeneous thermal conductivity could indicate a vertical flow component even though flow is actually horizontal. This work demonstrates how modeling can be used to simulate instrument response to formation heterogeneity, and shows that caution must be used in interpreting data from such devices using overly simplistic assumptions.
Date: June 13, 2005
Creator: Su, Grace W.; Freifeld, Barry M.; Oldenburg, Curtis M.; Jordan,Preston D. & Daley, Paul F.
Partner: UNT Libraries Government Documents Department

SEQUESTERING AGENTS FOR METAL IMMOBILIZATION APPLICATION TO THE DEVELOPMENT OF ACTIVE CAPS IN FRESH AND SALT WATER SEDIMENTS

Description: This research evaluated the removal of inorganic contaminants by a variety of amendments and mixtures of amendments in fresh and salt water. A series of removal and retention batch experiments was conducted to identify the best treatment for metal removal. Metal removal by the amendments was evaluated by calculating the partition coefficient and percent removal. Retention of metals by the amendments was evaluated in retention (desorption) studies in which residue from the removal studies was extracted with 1 M MgCl{sub 2} solution. The results indicated that phosphate amendments, some organoclays (e.g., OCB-750), and the biopolymer, chitosan, are very effective in removal and retention of metals in both fresh and salt water. These amendments are being evaluated further as components in the development of active caps for sediment remediation.
Date: November 17, 2006
Creator: Knox, A & Michael Paller, M
Partner: UNT Libraries Government Documents Department

Effects of uncertainty in rock-physics models on reservoirparameter estimation using marine seismic AVA and CSEM data

Description: This study investigates the effects of uncertainty inrockphysics models on estimates of reservoir parameters from jointinversion of seismic AVA and CSEMdata. The reservoir parameters arerelated to electrical resistivity using Archie's law, and to seismicvelocity and density using the Xu-White model. To account for errors inthe rock-physics models, we use two methods to handle uncertainty: (1)the model outputs are random functions with modes or means given by themodel predictions, and (2) the parameters of the models are themselvesrandom variables. Using a stochastic framework and Markov Chain MonteCarlo methods, we obtain estimates of reservoir parameters as well as ofthe uncertainty in the estimates. Synthetic case studies show thatuncertainties in both rock-physics models and their associated parameterscan have significant effects on estimates of reservoir parameters. Ourmethod provides a means of quantifying how the uncertainty in theestimated reservoir parameters increases with increasing uncertainty inthe rock-physics model and in the model parameters. We find that in theexample we present, the estimation of water saturation is relatively lessaffected than is the estimation of clay content and porosity.
Date: April 9, 2007
Creator: Chen, Jinsong & Dickens, Thomas
Partner: UNT Libraries Government Documents Department

Effects of Heavy, Tracked-Vehicle Disturbance on Forest Soil Properties at Fort Benning, Georgia

Description: The purpose of this report is to describe the effects of heavy, tracked-vehicle disturbance on various measures of soil quality in training compartment K-11 at Fort Benning, Georgia. Predisturbance soil sampling in April and October of 2002 indicated statistically significant differences in soil properties between upland and riparian sites. Soil density was less at riparian sites, but riparian soils had significantly greater C and N concentrations and stocks than upland soils. Most of the C stock in riparian soils was associated with mineral-associated organic matter (i.e., the silt + clay fraction physically separated from whole mineral soil). Topographic differences in soil N availability were highly dependent on the time of sampling. Riparian soils had higher concentrations of extractable inorganic N than upland soils and also exhibited significantly greater soil N availability during the spring sampling. The disturbance experiment was performed in May 2003 by driving a D7 bulldozer through the mixed pine/hardwood forest. Post-disturbance sampling was limited to upland sites because training with heavy, tracked vehicles at Fort Benning is generally confined to upland soils. Soil sampling approximately one month after the experiment indicated that effects of the bulldozer were limited primarily to the forest floor (O-horizon) and the surface (0-10 cm) mineral soil. O-horizon dry mass and C stocks were significantly reduced, relative to undisturbed sites, and there was an indication of reduced mineral soil C stocks in the disturbance zone. Differences in the surface (0-10 cm) mineral soil also indicated a significant increase in soil density as a result of disturbance by the bulldozer. Although there was some tendency for greater soil N availability in disturbed soils, the changes were not significantly different from undisturbed controls. It is expected that repeated soil disturbance over time, which will normally occur in a military training area, would simply intensify the ...
Date: May 20, 2004
Creator: Garten, C.T.,JR.
Partner: UNT Libraries Government Documents Department

Lateral Earth Pressure at Rest and Shear Modulus Measurements on Hanford Sludge Simulants

Description: This report describes the equipment, techniques, and results of lateral earth pressure at rest and shear modulus measurements on kaolin clay as well as two chemical sludge simulants. The testing was performed in support of the problem of hydrogen gas retention and release encountered in the double- shell tanks (DSTs) at the Hanford Site near Richland, Washington. Wastes from single-shell tanks (SSTs) are being transferred to double-shell tanks (DSTs) for safety reasons (some SSTs are leaking or are in danger of leaking), but the available DST space is limited.
Date: September 30, 2010
Creator: Wells, Beric E.; Jenks, Jeromy WJ; Boeringa, Gregory K.; Bauman, Nathan N.; Guzman, Anthony D.; Arduino, P. et al.
Partner: UNT Libraries Government Documents Department

In situ clay formation : evaluation of a proposed new technology for stable containment barriers.

Description: Containment of chemical wastes in near-surface and repository environments is accomplished by designing engineered barriers to fluid flow. Containment barrier technologies such as clay liners, soil/bentonite slurry walls, soil/plastic walls, artificially grouted sediments and soils, and colloidal gelling materials are intended to stop fluid transport and prevent plume migration. However, despite their effectiveness in the short-term, all of these barriers exhibit geochemical or geomechanical instability over the long-term resulting in degradation of the barrier and its ability to contain waste. No technologically practical or economically affordable technologies or methods exist at present for accomplishing total remediation, contaminant removal, or destruction-degradation in situ. A new type of containment barrier with a potentially broad range of environmental stability and longevity could result in significant cost-savings. This report documents a research program designed to establish the viability of a proposed new type of containment barrier derived from in situ precipitation of clays in the pore space of contaminated soils or sediments. The concept builds upon technologies that exist for colloidal or gel stabilization. Clays have the advantages of being geologically compatible with the near-surface environment and naturally sorptive for a range of contaminants, and further, the precipitation of clays could result in reduced permeability and hydraulic conductivity, and increased mechanical stability through cementation of soil particles. While limited success was achieved under certain controlled laboratory conditions, the results did not warrant continuation to the field stage for multiple reasons, and the research program was thus concluded with Phase 2.
Date: March 1, 2004
Creator: Nagy, Kathryn L. (University of Illinois at Chicago, Chicago, IL); DiGiovanni, Anthony Albert & Fredrich, Joanne T.
Partner: UNT Libraries Government Documents Department

SALINITY AND SODICITY INTERACTIONS OF WEATHERED MINESOILS IN NORTHWESTERN NEW MEXICO AND NORTH EASTERN ARIZONA

Description: Weathering characteristics of minesoils and rooting patterns of key shrub and grass species were evaluated at sites reclaimed for 6 to 14 years from three surface coal mine operations in northwestern New Mexico and northeastern Arizona. Non-weathered minesoils were grouped into 11 classifications based on electrical conductivity (EC) and sodium adsorption ratio (SAR). Comparisons of saturated paste extracts, from non-weathered and weathered minesoils show significant (p < 0.05) reductions in SAR levels and increased EC. Weathering increased the apparent stability of saline and sodic minesoils thereby reducing concerns of aggregate slaking and clay particle dispersion. Root density of four-wing saltbush (Atriplex canascens), alkali sacaton (Sporobolus airoides), and Russian wildrye (Psathyrostachys junceus) were nominally affected by increasing EC and SAR levels in minesoil. Results suggest that saline and sodic minesoils can be successfully reclaimed when covered with topsoil and seeded with salt tolerant plant species.
Date: May 1, 2006
Creator: Musslewhite, Brent & Jin, Song
Partner: UNT Libraries Government Documents Department