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Effect on Sediment Yield and Water Quality of a Nonrehabilitated Surface Coal Mine in North-Central Wyoming

Description: From introduction: The purpose of this study was to determine the magnitude of some effects of an abandoned surface coal mine on the hydrologic environment. Specific objectives were (1) to define areas of erosion and deposition; (2) to determine if the sediment yield from an undisturbed drainage basin was less than that from a drainage basin partly disturbed by mining activity; and (3) to determine if there were differences in chemical composition of hillslope materials, sediment, and pond water in the two basins.
Date: March 1979
Creator: Ringen, Bruce H.; Shown, Lynn M.; Hadley, Richard F. & Hinkley, Todd K.
Partner: UNT Libraries Government Documents Department


Description: Torrefaction tests were carried out on miscanthus samples in order to understand the changes in chemical composition at temperatures of 250–350°C and residence times of 30–120 minutes. The raw material chemical composition was moisture content 7.97%, moisture-free carbon (C) 47.73%, hydrogen (H) 5.85%, nitrogen (N) 0.28%, sulphur (S) 0.02%, volatiles (V) 83.29% for volatiles, and moisture and ash-free (MAF) calorific value (CV) 8423 BTU/lb (19.59 MJ/kg). Torrefaction at temperatures of 250°C and residence time of 30 minutes resulted in a significant decrease in moisture by about 82.68%, but the other components, C, H, N, S, and V changed only marginally. Increasing the torrefaction temperature to 350°C and residence time to 120 minutes further reduced the moisture to a final value of 0.54% (a 93.2% reduction compared to original) and also resulted in a significant decrease in the other components, H, N, and V by 58.29%, 14.28%, and 70.45%, respectively. The carbon content at 350°C and 120 minutes increased by about 4% and sulfur values were below detection limits. The calorific values increased by about 5.59% at 250°C and 30 minutes, whereas at 350°C and 120 minutes, the increase was much greater (about 75.61%) and resulted in a maximum degree of carbonization of 1.60. The H/C ratio decreased with an increase in torrefaction temperature, where a minimum value of 0.6 was observed at 350°C and 120 minutes. The regression equations developed with respect to torrefaction temperature and times have adequately described the changes in chemical composition. The surface plots developed based on the regression equations indicate that torrefaction temperatures of 300–350°C and residence times of 30–120 minutes residence time can help to increase carbon content, calorific value, and degree of carbonization to > 49.4%, >11,990 BTU/lb (27 MJ/kg), and 1.4, and reduce moisture, nitrogen, volatile, and the H/C ratio to 0.525–0.725, ...
Date: November 1, 2001
Creator: Tumuluru, Jaya Shankar; Boardman, Richard; Wright, Christopher & Heintzelman, John
Partner: UNT Libraries Government Documents Department

Correlation between Crystallographic and Magnetic Domains at Co/NiO(001) Interfaces

Description: Using soft x-ray spectromicroscopy we show that NiO(001) exhibits a crystallographic and magnetic domain structure near the surface identical to that of the bulk. Upon Co deposition a perpendicular coupling between the Ni and Co moments is observed that persists even after formation of uncompensated Ni spins at the interface through annealing. The chemical composition at the interface alters its crystallographic structure and leads to a reorientation of the Ni moments from the <112> to the <110> direction. We show that this reorientation is driven by changes in the magnetocrystalline anisotropy rather than exchange coupling mediated by residual uncompensated spins.
Date: December 18, 2008
Creator: Ohldag, H.; van der Laan, G. & Arenholz, E.
Partner: UNT Libraries Government Documents Department

Composition of the essential oils from Rocky Mountain juniper (Juniperus scopulorum), Big sagebrush (Artemisia tridentata), and White Sage (Salvia apiana).

Description: The essential oils of Juniperus scopulorum, Artemisia tridentata, and Salvia apiana obtained by steam extraction were analyzed by GC-MS and GC-FID. For J. scopulorum, twenty-five compounds were identified which accounts for 92.43% of the oil. The primary constituents were sabinene (49.91%), {alpha}-terpinene (9.95%), and 4-terpineol (6.79%). For A. tridentata, twenty compounds were identified which accounts for 84.32% of the oil. The primary constituents were camphor (28.63%), camphene (16.88%), and 1,8-cineole (13.23%). For S. apiana, fourteen compounds were identified which accounts for 96.76% of the oil. The primary component was 1,8-cineole (60.65%).
Date: September 1, 2003
Creator: Hochrein, James Michael; Irwin, Adriane Nadine & Borek, Theodore Thaddeus III
Partner: UNT Libraries Government Documents Department

Delineating the major KREEP-bearing terranes on the moon with global measurements of absolute thorium abundances

Description: The Lunar Prospector (LP) Gamma-Ray Spectrometer (GRS) has been used to map the global composition of thorium on the lunar surface. Previous LP results of relative thorium abundances demonstrated that thorium is highly concentrated in and around the nearside western maria and less so in the South Pole Aitken (SPA) basin. Using new detector modeling results and a larger data set, the authors present here a global map of absolute thorium abundances on a 2{degree} by 2{degree} equal-area pixel scale. Because thorium is a tracer of KREEP-rich material, these data provide fundamental information regarding the locations and importance of terranes that are rich in KREEP bearing materials.
Date: March 1, 1999
Creator: Lawrence, D.J.; Feldman, W.C.; Barraclough, B.L.; Elphic, R.C.; Prettyman, T.H.; Binder, A.B. et al.
Partner: UNT Libraries Government Documents Department

Effect on Performance of Composition of Li-Ion Carbon Anodes Derived from PMAN/DVB Copolymers

Description: The effects on electrochemical performance of the nitrogen content of disordered carbons derived from polymethacryonitrile (PMAN)-divinylbenzene (DVB) copolymers were examined in galvanostatic cycling tests between 2 V and 0.01 V vs. Li/Li+ in lM LiPF<sub>6</sub>/ethylene carbonate (EC)-dimethyl carbonate (DMC). The first-cycle reversible capacities and coulombic efficiencies increased with increase in the level of nitrogen for samples prepared at 700&deg;C. However, the degree of fade also increased. Similar tests were performed on materials that were additionally heated at 1,000&deg; and 1,300&deg;C for five hours. Loss of nitrogen, oxygen, and hydrogen occurred under these conditions, with none remaining at the highest temperature in all cases but one. The pyrolysis temperature dominated the electrochemical performance for these samples, with lower reversible and irreversible capacities for the first intercalation cycle as the pyrolysis temperature was increased. Fade was reduced and coulombic efficiencies also improved with increase in temperate. The large irreversible capacities and high fade of these materials makes them unsuitable for use in Li-ion cells.
Date: May 14, 1999
Creator: Even, William R. & Guidotti, Ronald A.
Partner: UNT Libraries Government Documents Department

History of ultrahigh carbon steels

Description: The history and development of ultrahigh carbon steels (i.e., steels containing between 1 and 2.l percent C and now known as UHCS) are described. The early use of steel compositions containing carbon contents above the eutectoid level is found in ancient weapons from around the world. For example, both Damascus and Japanese sword steels are hypereutectoid steels. Their manufacture and processing is of interest in understanding the role of carbon content in the development of modern steels. Although sporadic examples of UHCS compositions are found in steels examined in the early part of this century, it was not until the mid-1970s that the modern study began. This study had its origin in the development of superplastic behavior in steels and the recognition that increasing the carbon content was of importance in developing that property. The compositions that were optimal for superplasticity involved the development of steels that contained higher carbon contents than conventional modern steels. It was discovered, however, that the room temperature properties of these compositions were of interest in their own right. Following this discovery, a period of intense work began on understanding their manufacture, processing, and properties for both superplastic forming and room temperature applications. The development of superplastic cast irons and iron carbides, as well as those of laminated composites containing UHCS, was an important part of this history.
Date: June 20, 1997
Creator: Wadsworth, J. & Sherby, O.D.
Partner: UNT Libraries Government Documents Department

Industrial Alcohol: Sources and Manufacture

Description: Report discussing the production and manufacturing process of denatured (or industrial) alcohol in the United States. Topics discussed include laws and regulations, materials from which alcohol can be produced, and the steps of the manufacturing process.
Date: 1911
Creator: Sawyer, H. E.
Partner: UNT Libraries Government Documents Department

Lower Saccharide Nanometric Materials and Methods

Description: A ceramic composition having at least one nanometric ceramic powder, at least one lower saccharide, and water. The composition is useful in many industrial applications, including preparation of stronger and substantially defect free green and sintered ceramic bodies.
Date: July 13, 2004
Creator: Schilling, Christopher H.; Tomasik, Piotr & Sikora, Marek
Partner: UNT Libraries Government Documents Department


Description: Two cylindrical freshwater microcosms with a volume of 700 {ell} were maintained under controlled laboratory conditions for 190 days. The two microcosms were identical with regard to initial chemical composition and biological inocula, with the exceptions that in one microcosm (designated Tank 2) mosquitofish (Gambusia) and herbivorous catfish (Placostomas) were added. Three distinct communities developed in the tanks: (1) a phytoplankton-zooplankton assemblage and (2) two periphyton-zoobenthos communities associated with the sides and bottom of the tank, respectively. Community development and successional patterns were similar in both tanks. Major differences between the tanks involved timing of succession of the zooplankton and zoobenthos, attributable to predation by fish, principally Gambusia. A major drawback for these microcosms as use for experimental analogs such as lakes was a luxuriant periphyton growth which eventually overwhelmed the biomass of the system. The tanks displayed a degree of successional replicability, a large number of species, and a diversity of community development. Microcosms of this size could find use as experimental systems for higher level trophic manipulation and observation of life cycles not amenable to field studies.
Date: January 1, 1978
Creator: Rees, John T.
Partner: UNT Libraries Government Documents Department


Description: The isoprenoid hydrocarbons, phytane (C{sub 20}H{sub 42}) and pristane (C{sub 19}H{sub 40}) are present in the oil seeping from the Pre-Cambrian Nonesuch Formation at the White Pine Mine, Michigan. Gas-liquid chromatography and mass spectrometry provide the isolation and identification procedures.
Date: May 1, 1964
Creator: Eglinton, Geoffrey.; Scott, P.M.; Belsky, Ted.; Burlingame, A.L.; Calvin, Melvin. & Cloud Jr., Preston E.
Partner: UNT Libraries Government Documents Department


Description: In March of 2007 a document was issued, see attachment I, that defined the test protocol and required welding for the Kansas City Plant to change cutting oils from the recently approved 50:50 oil to an oil with similar characteristics but with different chemistry, additives, and possibly a different vendor due to plans by the current vendor to stop preparing the oils that are used in the KCP 50:50 mix. The KCP manufactured stems with the existing 50:50 oil blend in late FY07 and SRNL welded the stems and evaluated them in agreement with the test plan. This report provides all the data from these set-up and test welds. Set-up welds were shot and low and high voltages (currents) to ensure the window limits were applicable and then additional welds were made to validate the window. The purpose of this report is to ensure that the agreed upon path forward is still applicable.
Date: February 22, 2008
Creator: Korinko, P & David Maxwell, D
Partner: UNT Libraries Government Documents Department


Description: The feasibility of producing the short-lived tracers {sup 11}C, {sup 13}N, {sup 15}O, and {sup 18}F with heavy-ion beams was investigated. Production cross sections for 15-MeV p, 75-MeV {sup 3}He, and 300-MeV {sup 12}C beams incident on H{sub 2}O targets were calculated using the particle evaporation code ALICE (3). These calculations predicted substantial thick target yields of all four activities with the heavier beams. Experiments were performed with 15-MeV p and 75-MeV {sup 3}He beams to check the accuracy of the theoretical calculations. Absolute product yields were measured with NaI well counters, and chemical composition was determined by GC and HPLC.
Date: May 1, 1980
Creator: Firestone, R.B.; Betlach, M.R.; Tiedje, J.M. & Firestone, M.K.
Partner: UNT Libraries Government Documents Department


Description: PETN is widely recognized as an example of nearly ideal detonation performance. The chemical composition is such that little or no carbon is produced in the detonation products. The reaction zone width is less than currently detectable. (&lt;1 ns) Observations on PETN have thus become a baseline for EOS model predictions. It has therefore become important to characterize the detonation parameters as accurately as possible in order to provide the most exacting comparisons of EOS predictions with experimental results. We undertook a painstaking review of the detonation pressure measurements reported in an earlier work that was presented at the Fifth Detonation Symposium and found that corrections were required in determining the shock velocity in the PMMA witness material. We also refined the impedance calculation to account for the difference between the usual ''acoustic'' method and the more accurate Riemann integral. Our review indicates that the CJ pressures previously reported for full density PETN require an average lowering of about 6 percent. The lower densities require progressively smaller corrections. We present analysis of the records, supporting hydrodynamic simulations, the Riemann integral results, and EOS parameter values derived from the revised results.
Date: June 23, 2006
Creator: Green, L. G. & Lee, E. L.
Partner: UNT Libraries Government Documents Department

Chemical Stimulation of Engineered Geothermal Systems

Description: The objective of this project is to design, develop and demonstrate methods for the chemical stimulation of candidate EGS reservoirs as well as the chemical treatment of mineral-scaled wellbores. First, a set of candidate chemical compounds capable of dissolving calcite was identified. A series of tests was then performed on each candidate in order to screen it for thermal stability and reactivity towards calcite. A detailed analysis was then performed on each compound that emerged from the screening tests in order to characterize its decay kinetics and reaction kinetics as functions of temperature and chemical composition. From among the compounds emerging from the laboratory studies, one compounds was chosen for a field experiment in order to verify the laboratory predictions.
Date: August 8, 2008
Creator: Rose, Peter, E.
Partner: UNT Libraries Government Documents Department

Examination of Corrosion Products and the Alloy Surface After Crevice Corrosion of a Ni-Cr-Mo- Alloy

Description: The objective of this study is to investigate the composition of corrosion products and the metal surface within a crevice after localized corrosion. The analysis provides insight into the propagation, stifling and arrest processes for crevice corrosion and is part of a program to analyze the evolution of localized corrosion damage over long periods of time, i.e. 10,000 years and longer. The approach is to force the initiation of crevice corrosion by applying anodic polarization to a multiple crevice assembly (MCA). Results are reported here for alloy C-22, a Ni-Cr-Mo alloy, exposed to a high temperature, concentrated chloride solution. Controlled crevice corrosion tests were performed on C-22 under highly aggressive, accelerated condition, i.e. 4M NaCl, 100 C and anodic polarization to -0.15V-SCE. The crevice contacts were by either a polymer tape (PTFE) compressed by a ceramic former or by a polymer (PTFE) crevice former. Figure 1 shows the polarization current during a crevice corrosion test. After an incubation period, several initiation-stifle-arrest events were indicated. The low current at the end of the test indicated that the metal surface had repassivated.
Date: June 9, 2006
Creator: Shan, X. & Payer, J.H.
Partner: UNT Libraries Government Documents Department

X-ray Scattering Techniques for Characterization of Nanosystems in Lifescience

Description: The intent of this chapter is to provide the basics of using x-ray diffraction techniques in order to obtain information on the structure and morphology of the nanosystems, and also to point out some of its strengths and weaknesses when compare to other characterization techniques. X-ray scattering examines over a wide range of density domains from a tenth to a thousandth angstrom. Essentially, this covers a whole range of condensed matter, including the structure and morphology of nanosystems, particularly useful for examining nanostructures in lifescience. This range of domain size requires both the wide-angle x-ray scattering (WAXS) and small-angle (SAXS) x-ray scattering techniques. Roughly WAXS covers from 2 nm down, and SAXS covers from .5 nm to 100 nm and possibly 1,000 nm for a finely tuned instrument. Brief theoretical description of both WAXS and SAXS will be given in this chapter. WAXS, by itself is a powerful technique in providing information on the crystallographic structure or lack of structure, atomic positions and sizes in a unit cell, to some extend, chemical compositions and as well as chemical stoichiometry. Examples of such experiments will also be given. In order to be able to describe the technique of x-ray scattering, some historical and theoretical background will be given in the hope of making this subject interesting and simple.
Date: April 11, 2005
Creator: Saw, C K
Partner: UNT Libraries Government Documents Department

Impact of Small Chemistry Variations in Plate and Weld Filler Metal on the Corrosion Performance of Ni-Cr-Mo Alloys

Description: The ASTM standard B 575 provides the requirements for the chemical composition of Nickel-Chromium-Molybdenum (Ni-Cr-Mo) alloys such as Alloy 22 (N06022) and Alloy 686 (N06686). The compositions of each element are given in a range. For example, the content of Mo is specified from 12.5 to 14.5 weight percent for Alloy 22 and from 15.0 to 17.0 weight percent for Alloy 686. It was important to determine how the corrosion rate of welded plates of Alloy 22 using Alloy 686 weld filler metal would change if heats of these alloys were prepared using several variations in the composition of the elements even though still in the range specified in B 575. Seven heats of plate were welded with seven heats of wire. Immersion corrosion tests were conducted in a boiling solution of sulfuric acid plus ferric sulfate (ASTM G 28 A) using both as-welded (ASW) coupons and solution heat-treated (SHT) coupons. Results show that the corrosion rate was not affected by the chemistry of the materials in the range specified in the standard B 575.
Date: February 5, 2006
Creator: Fix, D V & Rebak, R B
Partner: UNT Libraries Government Documents Department

Cyclic and Linear Polarization of Yttrium-Containing Iron-Based Amorphous Alloys

Description: Iron-based amorphous alloys are produced by rapid solidification from the melt. These alloys may possess unique mechanical and corrosion resistant properties. The chemical composition of the alloy may influence the cooling rate that is necessary for the alloys to be completely vitreous. At the same time, the corrosion resistance of the amorphous alloys may also depend on their chemical composition. This paper examines the anodic behavior of iron-based amorphous alloys containing three different concentrations (1, 3 and 5 atomic %) of yttrium (Y) in several electrolyte solutions. Results from polarization resistance potentiodynamic polarization show that when the alloy contains 5% atomic Y, the corrosion resistance decreases.
Date: August 10, 2007
Creator: Day, S D; Lian, T; Farmer, J C & Rebak, R B
Partner: UNT Libraries Government Documents Department

Structure/property relationships in multipass GMA welding of beryllium.

Description: Beryllium is an interesting metal that has a strength to weight ratio six times that of steel. Because of its unique mechanical properties, beryllium is used in aerospace applications such as satellites. In addition, beryllium is also used in x-ray windows because it is nearly transparent to x-rays. Joining of beryllium has been studied for decades (Ref.l). Typically joining processes include braze-welding (either with gas tungsten arc or gas metal arc), soldering, brazing, and electron beam welding. Cracking which resulted from electron beam welding was recently studied to provide structure/property relationships in autogenous welds (Ref. 2). Braze-welding utilizes a welding arc to melt filler, and only a small amount of base metal is melted and incorporated into the weld pool. Very little has been done to characterize the braze-weld in terms of the structure/property relationships, especially with reference to multipass welding. Thus, this investigation was undertaken to evaluate the effects of multiple passes on microstructure, weld metal composition, and resulting material properties for beryllium welded with aluminum-silicon filler metal.
Date: January 1, 2001
Creator: Hochanadel, P. W. (Patrick W.); Hults, W. L. (William L.); Thoma, D. J. (Dan J.); Dave, V. R. (Vivek R.); Kelly, A. M. (Anna Marie); Pappin, P. A. (Pallas A.) et al.
Partner: UNT Libraries Government Documents Department