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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

CHANGES IN MOISTURE, CARBON, NITROGEN, SULPHUR, VOLATILES, AND CALORIFIC VALUE OF MISCANTHUS DURING TORREFACTION

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

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

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

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

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

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

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 &lt;112&gt; to the &lt;110&gt; 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

Effect of different glasses in glass bonded zeolite

Description: A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immobilizes the fission products. The zeolite powders are hot pressed to form a mechanically stable, durable glass bonded zeolite. Further development of glass bonded zeolite as a waste form requires an understanding of the interaction between the glass and the zeolite. Properties of the glass that enhance binding and durability of the glass bonded zeolite need to be identified. Three types of glass, boroaluminosilicate, soda-lime silicate, and high silica glasses, have a range of properties and are now being investigated. Each glass was hot pressed by itself and with an equal amount of zeolite. MCC-1 leach tests were run on both. Soda-lime silicate and high silica glasses did not give a durable glass bonded zeolite. Boroaluminosilicate glasses rich in alkaline earths did bind the zeolite and gave a durable glass bonded zeolite. Scanning electron micrographs suggest that the boroaluminosilicate glasses wetted the zeolite powders better than the other glasses. Development of the glass bonded zeolite as a waste form for chloride waste salt is continuing.
Date: May 1, 1995
Creator: Lewis, M.A.; Ackerman, J.P. & Verma, S.
Partner: UNT Libraries Government Documents Department

The determination of PCBs in Rocky Flats Type IV waste sludge by gas chromatography/electron capture detection. Part 2

Description: Before disposal, radioactive sludge (Type IV) from Rocky Flats Plant (RFP) must be evaluated for polychlorinated biphenyl (PCB) content. The Type IV sludge consists of organic solvents, degreasers, cutting oils, and transuranic (TRU) waste mixed with calcium silicate (MicroCel E{reg_sign} and Oil Dri{reg_sign} to form a grease or paste-like material. For laboratory testing, a nonradioactive simulated Type 17V RFP sludge was prepared at Argonne National Laboratory-East (ANL-E). This sludge has a composition similar to that expected from field samples. In an earlier effort, a simplified method was developed for extraction, cleanup of extract, and determination of PCBs in samples of simulated sludge spiked with Aroclors 1254 and 1260. The simplified method has now been used to determine the presence and quantities of other Aroclors in the simulated sludge, namely, Aroclors 10 1 6, 1221, 1232, 1242, and 1248. The accuracy and precision of the data for these Aroclors were found to be similar to the data for sludges spiked with Aroclors 1254 and 1260. Since actual sludges may vary in composition, the method was also verified by analyzing another source of Type IV simulated sludge, prepared by Argonne National Laboratory-West (ANL-W).
Date: December 1, 1994
Creator: Parish, K.J.; Applegate, D.V.; Postlethwait, P.D.; Boparai, A.S. & Reedy, G.T.
Partner: UNT Libraries Government Documents Department

Effect of gas composition on the NO<sub>x</sub> conversion chemistry in a plasma

Description: Much work has been done on the application of plasmas to the treatment of NO<sub>x</sub> from power plants. In power plant applications, the purpose of the plasma is to oxidize NO to NO<sub>x</sub>, and eventually to nitric acid. The desires products, in the form of ammonium salts, are then obtained by mixing ammonia with the formed acids. Some form of scrubbing is required to collect the final products. For applications to the treatment of exhausts from cars and trucks, it is very important to make a distinction between NO removal by chemical oxidation and NO removal by chemical reduction. To avoid the need for scrubbing of plasma processing products, the desired method of NO removal is by chemical reduction; i.e., the conversion of NO to benign gaseous products like N NO<sub>2</sub>. This paper will discuss the results of an extensive series of experiments aimed towards understanding the effect of gas composition on the NO<sub>x</sub> conversion chemistry in a plasma. The NO<sub>x</sub> conversion chemistry in the presence of the individual components, such as N<sub>2</sub>, O<sub>2</sub>, H<sub>2</sub>O, and CO<sub>2</sub>, as well as the mixture of these, will be presented. We will show that, in a lean-burn gasoline or diesel engine exhaust, the main effect of the gas-phase reactions in a plasma is the oxidation of NO to NO<sub>x</sub> and nitric acid. To implement the reduction of NO<sub>x</sub> to N<sub>2</sub> in the highly oxidizing environment of a lean-burn engine exhaust, it will be necessary to prevent the formation of acid products and combine the plasma with another process that can chemically reduce NO<sub>2</sub> to N<sub>x</sub>.
Date: August 24, 1998
Creator: McLarnon, C R & Penetrante, B M
Partner: UNT Libraries Government Documents Department

Chemistry modification of high oxygen-carbon powder by plasma melting: Follow up to complete the story

Description: State of the art melting of tantalum and tantalum alloys has relied on electron beam (EB) or vacuum arc remelting (VAR) for commercial ingot production. Plasma arc melting (PAM) provides an alternative for melting tantalum that contains very high levels of interstitials where other melting techniques can not be applied. Previous work in this area centered on plasma arc melt quality and final interstitial content of tantalum feedstock containing excessive levels of interstitial impurities as a function of melt rate and plasma gas. This report is an expansion of this prior study and provides the findings from the analysis of second phase components observed in the microstructure of the PAM tantalum. In addition, results from subsequent EB melting trials of PAM tantalum are included.
Date: March 1, 1998
Creator: Dunn, P.S.; Korzekwa, D.R.; Garcia, F.G. & Michaluk, C.A.
Partner: UNT Libraries Government Documents Department

Clean, agile alternative binders, additives and plasticizers for propellant and explosive formulations

Description: As part of the Strategic Environmental Research and Development Program (SERDP) a clean, agile manufacturing of explosives, propellants and pyrotechniques (CANPEP) effort set about to identify new approaches to materials and processes for producing propellants, explosives and pyrotechniques (PEP). The RDX based explosive PBXN-109 and gun propellant M-43 were identified as candidates for which waste minimization and recycling modifications might be implemented in a short time frame. The binders, additives and plasticizers subgroup identified cast non-curable thermoplastic elastomer (TPE) formulations as possible replacement candidates for these formulations. Paste extrudable explosives were also suggested as viable alternatives to PBXN-109. Commercial inert and energetic TPEs are reviewed. Biodegradable and hydrolyzable binders are discussed. The applicability of various types of explosive formulations are reviewed and some issues associated with implementation of recyclable formulations are identified. It is clear that some processing and weaponization modifications will need to be made if any of these approaches are to be implemented. The major advantages of formulations suggested here over PBXN-109 and M-43 is their reuse/recyclability. Formulations using TPE or Paste could by recovered from a generic bomb or propellant and reused if they met specification or easily reprocessed and sold to the mining industry.
Date: December 1, 1994
Creator: Hoffman, D.M.; Hawkins, T.W. & Lindsay, G.A.
Partner: UNT Libraries Government Documents Department

Lunar prospector measurements of the distribution of incompatible elements gadolinium, samarium and thorium

Description: Lunar Prospector neutron spectrometer (NS) and gamma ray spectrometer (GRS) observations have been used to map out the distribution of incompatible elements on the lunar surface. Specifically, the GRS data provide maps of the distribution of thorium and potassium while the NS data provide information on the distribution of iron and titanium, and the rare earth elements gadolinium and samarium. Using results of analysis of Celementine spectral reflectance (CSR) data, the Fe- and Ti-contributions to the NS data can be removed, leaving primarily rare earth element contributions from Gd and Sm. The Th and K maps correlate with the inferred Gd and Sm maps (r {approximately} 0.93), but there are regions of significant disagreement. One of these is in the KREEP-rich circum-Imbrium ring. No clear explanation has emerged for this disagreement, though Th, K, Gd and Sm have differing degrees of incompatibility. These results clearly are important to discussions of the geochemistry of the Procellarum-Imbrium Th-rich Terrane and the South-Pole-Aitken Terrane.
Date: April 1, 1999
Creator: Elphic, R.C.; Lawrence, D.J.; Feldman, W.C.; Barraclough, B.L.; Maurice, S.; Binder, A.B. et al.
Partner: UNT Libraries Government Documents Department

Mapping the elemental composition of the moon: Current results of the Lunar Prospector gamma ray spectrometer

Description: One of the instruments on board the recently launched Lunar Prospector spacecraft is a Gamma-Ray Spectrometer (GRS) designed to map the surface elemental composition of the Moon. Specifically, the objectives of the GRS are to map abundances of Fe, Ti, U, Th, K, Si, O and if possible Mg, Al, and Ca. The GRS consists of a bismuth germanate (BGO) crystal placed within a well shaped borated plastic scintillator anti-coincidence (ACS) shield. Events triggering only the BGO are labeled as accepted events; events triggering both the BGO and ACS are labeled as rejected events. BGO spectra for both accepted and rejected events are telemetered to the ground for later analysis. Results of the study are given.
Date: December 1, 1998
Creator: Lawrence, D.J.; Feldman, W.C.; Barraclough, B.L.; Elphic, R.C.; Binder, A.B. & Maurice, S.
Partner: UNT Libraries Government Documents Department

Scale-up of the nitridation and sintering of silicon preforms using microwave heating

Description: Scale-up studies were performed in which microwave heating was used to fabricate reaction-bonded silicon nitride and sintered reaction-bonded silicon nitride (SRBSN). Tests were performed in both a 2.45 GHz, 500 liter and a 2.45 GHz, 4,000 liter multimode cavities. A variety of sizes, shapes, and compositions of silicon preforms were processed in the studies, including bucket tappets and clevis pins for diesel engines. Up to 230 samples were processed in a single microwave furnace run. Data were collected which included weight gains for nitridation experiments, and final densities for nitridation and sintering experiments. For comparison, nitridation and sintering studies were performed using a conventional resistance-heated furnace.
Date: May 1, 1996
Creator: Kiggans, J.O. Jr.; Tiegs, T.N.; Davisson, C.C.; Morrow, M.S. & Garvey, G.J.
Partner: UNT Libraries Government Documents Department

Vitrification of Simulated Fernald K-65 Silo Waste at Low Temperature

Description: Vitrification is the technology that has been chosen to solidify approximately 15,500 tons of geologic mill tailings at the Fernald Environmental Management Project (FEMP) in Fernald, Ohio. The geologic mill tailings are residues from the processing of pitchlende ore during 1949-1958. These waste residues are contained in silos in Operable Unit 4 (OU4) at the FEMP facility. Operable Unit 4 is one of five operable units at the FEMP. Operating Unit 4 consists of four concrete storage silos and their contents. Silos 1 and 2 contain K-65 mill tailing residues and a bentonite cap, Silo 3 contains non-radioactive metal oxides, and Silo 4 is empty. The K-65 residues contain radium, uranium, uranium daughter products, and heavy metals such as lead and barium.The K-65 waste leaches lead at greater than 100 times the allowable Environmental Protection Agency (EPA) Resource, Conservation, and Recovery Act (RCRA) concentration limits when tested by the Toxic Characteristic Leaching Procedure (TCLP). Vitrification was chosen by FEMP as the preferred technology for the Silos 1, 2, 3 wastes because the final waste form met the following criteria: controls radon emanation, eliminates the potential for hazardous or radioactive constituents to migrate to the aquifer below FEMP, controls the spread of radioactive particulates, reduces leachability of metals and radiological constituents, reduces volume of final wasteform for disposal, silo waste composition is favorable to vitrification, will meet current and proposed RCRA TCLP leaching criteria Glasses that melt at 1350 degrees C were developed by Pacific Northwest National Laboratory (PNNL) and glasses that melt between 1150-1350 degrees C were developed by the Vitreous State Laboratory (VSL) for the K-65 silo wastes. Both crucible studies and pilot scale vitrification studies were conducted by PNNL and VSL. Subsequently, a Vitrification Pilot Plant (VPP) was constructed at FEMP capable of operating at temperatures up to ...
Date: January 14, 1998
Creator: Jantzen, C.M. & Pickett, J.B.
Partner: UNT Libraries Government Documents Department

Glass Waste Forms for Oak Ridge Tank Wastes: Fiscal Year 1997 Report for Task Plan SR-16WT-31, Task A

Description: Through the Tanks Focus Area, the Office of Science and Technology has funded the Savannah River Technology Center (SRTC) and the Oak Ridge National Laboratory (ORNL) to develop formulations which can incorporate sludges from Oak Ridge (OR) Tank Farms into an immobilized waste form. SRTC has been developing a glass waste form, while ORNL has been developing a grout waste form for the tank farms sludges. The four tank farms included in this task are: Melton Valley Storage Tanks (MVST), Bethel Valley Evaporator Service Tanks (BVEST), Gunite and Associated Tanks (GAAT)and Old Hydrofracture Tanks (OHF). The first element of the SRTC task for FY97 was to develop a glass formulation to immobilize a blended sludge from the MVST and the BVEST. ORNL had previously developed a soda-lime-silicate (SLS) glass for the MVST sludge. SRTC has reproduced this work and expanded on it for the blended MVST/BVEST sludge. SRTC also performed a durability test on the resultant glasses. The normalized sodium and silicon leachate concentrations for the soda lime silica glasses readily met the Environmental Assessment glass (a borosilicate glass) benchmark limits for these two elements. Additional efforts at the SRTC included the verification of the glass formulation prior to the ORNL radioactive demonstration and technical consultations during the radioactive demonstration. However, the major emphasis for SRTC in FY97 was on the second element of this task, the overall blended average of the tank farms. The second element focused on developing a glass formulation which would immobilize a sludge with a composition obtained from averaging the contents of all four tank farms (composite composition). Although blending the contents of all four tank farms is not feasible, this average composition provides a basis from which to develop a glass formulation. Once a frit formulation was developed which produced a durable glass waste ...
Date: October 1, 1997
Creator: Andrews, M.K.; Harbour, J.R.; Edwards, T.B. & Workman, P.J.
Partner: UNT Libraries Government Documents Department

Use of remote sensing to identify waste sources at ORNL`s SWSA 4

Description: Solid waste storage area (SWSA) 4, at Oak Ridge National Laboratory (ORNL), contributes 25% of the {sup 90}Sr release from the ORNL complex. Disposal records were destroyed in a fire, thus limiting the ability to locate waste sources contributing to the releases. The use of remote sensing products, including photos and thermal spectra images, provided the needed information to allow field work to progress in an efficient and cost-effective manner. As a result, four major sources were identified. Preliminary estimates suggest that cost avoidance in excess of $5 million will be possible because of the detailed source location knowledge.
Date: December 1995
Creator: Huff, D. D.; Doll, W. E. & Nyquist, J. E.
Partner: UNT Libraries Government Documents Department