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Effects of Coal Fly-Ash Disposal on Water Quality in and Around the Indiana Dunes National Lakeshore, Indiana

Description: Abstract: Dissolved constituents in seepage from fly-ash settling ponds bordering part of the Indiana Dunes National Lakeshore (the Lakeshore) have increased trace elements, and gross alpha and gross beta radioactivity in the ground water and surface water downgradient from the settling ponds. Data suggest that concentrations of some dissolved trace elements may be greater beneath interdunal pond 2 than in the pond. The soil system downgradient from the settling ponds seems to have affected the concentrations of dissolved ions in the settling-ponds than in the ponds. Where organic material was present downgradient from the settling ponds, concentrations of arsenic, fluoride, molybdenum, potassium, sulfate, and strontium were greater in the ground water than in the ponds. In contrast, the concentrations of cadmium, copper, nickel, aluminum, cobalt, lead, and zinc were less.
Date: April 1981
Creator: Hardy, Mark A.
Partner: UNT Libraries Government Documents Department

Summary of beryllium specifications

Description: This report summarizes and compares the main beryllium properties included in producer, Department of Energy (formerly ERDA) facility, and government specifications. These data are tabulated in a sequence established primarily by increasing purity and secondarily by increasing tensile properties. Comments on formability and weldability are also included.
Date: February 17, 1978
Creator: Corle, R. R.
Partner: UNT Libraries Government Documents Department

Advanced liquefaction using coal swelling and catalyst dispersion techniques. Volume 2, appendices. Final technical report, October 1, 1991--September 30, 1994

Description: Liquefaction experiments were undertaken using subbituminous Black Thunder mine coal to observe the effects of aqueous SO{sub 2} coal beneficiation and the introduction of various coal swelling solvents and catalyst precursors. Aqueous SO{sub 2} beneficiation of Black Thunder coal removed alkali metals and alkaline earth metals, increased the sulfur content and increased the catalytic liquefaction conversion to THF solubles compared to untreated Black Thunder coal. The liquefaction solvent had varying effects on coal conversion, depending upon the type of solvent added. The hydrogen donor solvent, dihydroanthracene, was most effective, while a coal-derived Wilsonville solvent promoted more coal conversion than did relatively inert 1-methylnaphthalene. Swelling of coal with hydrogen bonding solvents tetrahydrofuran (THF), isopropanol, and methanol, prior to reaction resulted in increased noncatalytic conversion of both untreated and SO{sub 2} treated Black Thunder coals, while dimethylsulfoxide (DMSO), which was absorbed more into the coal than any other swelling solvent, was detrimental to coal conversion. Swelling of SO{sub 2} treated coal before liquefaction resulted in the highest coal conversions; however, the untreated coal showed the most improvements in catalytic reactions when swelled in either THF, isopropanol, or methanol prior to liquefaction. The aprotic solvent DMSO was detrimental to coal conversion.
Date: April 1, 1995
Creator: Curtis, C.W.; Chander, S. & Gutterman, C.
Partner: UNT Libraries Government Documents Department

Synergistic effects in the extraction of metal ions by mixtures of dialkylphosphoric acids and substituted crown ethers.

Description: The extraction of alkaline earth cations from weakly acidic solutions by three dialkylphosphoric acids and various isomers of dicyclohexano-18-crown-6, both alone and in combination in toluene solutions, has been examined to determine the effect of both the crown ether stereochemistry and the structure of the organophilic anion on the magnitude of the synergistic effects. The synergistic effects have been found to differ considerably among the crown ether isomers and to vary with the extent of alkyl chain branching in the dialkylphosphoric acid. Attempts to correlate the synergistic effects with ligand strain energies from molecular mechanics calculations are described.
Date: December 3, 1998
Creator: Chiarizia, R.
Partner: UNT Libraries Government Documents Department

Equation of state of beryllium

Description: A new, wide-range equation of state (EOS) has been constructed for Be. The composite theoretical model incorporates ionization equilibrium and condensed-matter and multiphase physics. It also satisfies all thermodynamic equilibrium constraints. The theoretical EOS has been compared with all available high-pressure and high-temperature Be data, and satisfactory agreement is generally achieved. The most interesting feature is the theoretical prediction of melting at just below 220 GPa (2 Mb), indicating an extremely wide pressure range for solid Be. A striking feature is the appearance of shell-structure effects in physical-process paths: 2 large loops appear on the principal Hugoniot and the behavior of release isentropes from rho = rho/sub 0/ is significantly affected.
Date: September 15, 1977
Creator: Graboske, H. & Wong, L.
Partner: UNT Libraries Government Documents Department

Casting large beryllium ingots

Description: Beryllium casting is a relatively new technology with the successful cast of large ingots being developed during the last decade. In 1961, Rocky Flats initiated a beryllium ingot-sheet fabrication process that included the development of new techniques to consistently cast large sound beryllium ingots. This report reviews the casting technology that was developed to cast these beryllium ingots on a production basis along with some of the remaining technical problems requiring additional development work.
Date: June 5, 1978
Creator: Corle, R.R.; Krenzer, R.W. & Voiles, K.E.
Partner: UNT Libraries Government Documents Department

SORPTION BEHAVIOR OF MONOSODIUM TITANATE AND AMORPHOUS PEROXOTITANATE MATERIALS UNDER WEAKLY ACIDIC CONDITIONS

Description: Inorganic, titanate-based sorbents are tested with respect to adsorption of a variety of sorbates under weakly acidic conditions (pH 3). Specifically, monosodium titanate (MST) and amorphous peroxotitanate (APT) sorption characteristics are initially probed through a screening process consisting of a pair of mixed metal solutions containing a total of 29 sorbates including alkali metals, alkaline earth metals, transition metals, metalloids and nonmetals. MST and APT sorption characteristics are further analyzed individually with chromium(III) and cadmium(II) using a batch method at ambient laboratory temperature, varying concentrations of the sorbents and sorbates and contact times. Maximum sorbate loadings are obtained from the respective adsorption isotherms.
Date: November 11, 2009
Creator: Hobbs, D.; Elvington, M. & Click, D.
Partner: UNT Libraries Government Documents Department

(Calcium gating of proton fluxes in chloroplasts)

Description: Work supported by this grant has been aimed at better understanding the still-mysterious phenomenon of sequestered proton gradients which strong evidence suggests can energize ATP formation in chloroplast organelle membranes. Results from several laboratories support the notion that chloroplasts can couple the energy of H{sup +} gradients. Research in may lab has, since 1983, been deeply involved in a two-pronged approach, (A) identifying and quantitating sequestered proton buffering groups and (B) trying to elucidate just how the sequestered H{sup +} gradient is maintained and what regulates the switching between the localized and delocalized coupling modes. One aspect we have worked on under DOE auspices is the question whether the localized H{sup +} coupling, routinely detected in my lab by a protocol which measures the number of single-turnover flashes (usually fired at 5 Hz) required to reach the energization threshold for ATP formation, can continue in steady illumination. It is possible to consider that a localized coupling response could be observed in the initial energization transient followed obligatorily by the sustained H{sup +} gradient equilibrating with the lumen bulk phase. If that occurred, it would have very important ramifications as to how one evaluates the possible physiological meaning of localized'' coupling. To test this, we developed a steady illumination protocol which is briefly discussed.
Date: January 1, 1991
Creator: Dilley, R.A.
Partner: UNT Libraries Government Documents Department

Energy calibration scheme for acoustic emission

Description: The calibration technique described is an attempt to determine the actual energy release from the events causing emission bursts in beryllium and to quantitatively evaluate the effects of specimen geometry on the apparent energy per burst. (GHT)
Date: September 13, 1977
Creator: Adams, R. O. & Heiple, C. R.
Partner: UNT Libraries Government Documents Department

Feasibility demonstration of consolidating porous beryllium/carbon structures. Final report

Description: A preliminary feasibility study was initiated to determine if porous beryllium structures could be fabricated by consolidating beryllium-coated microballoons into a rigid structure. The target specifications were to coat nominally 1-mm diameter microspheres with 0.5-mil beryllium coatings and then bond into a structure. Because of the very short time period, it was agreeable to use existing or quickly-available materials. The general approach was to apply coatings to carbon or quartz microspheres. Physical vapor deposition and ''snow-balling'' of fine beryllium powder were the two methods investigated. Once the particles were coated, HIP (pressure bonding) and pressureless sintering were to be investigated as methods for consolidating the microballoons. A low level of effort was to be spent to look at means of fabricating an all-carbon structure.
Date: November 11, 1977
Creator: Browning, M.J.; Hoover, G.E.; Mueller, J.J. & Hanes, H.D.
Partner: UNT Libraries Government Documents Department

Consistent stress-strain ductile fracture model as applied to two grades of beryllium

Description: Published yield and ultimate biaxial stress and strain data for two grades of beryllium are correlated with a more complete method of characterizing macroscopic strain at fracture initiation in ductile materials. Results are compared with those obtained from an exponential, mean stress dependent, model. Simple statistical methods are employed to illustrate the degree of correlation for each method with the experimental data.
Date: January 1, 1980
Creator: Priddy, T.G.; Benzley, S.E. & Ford, L.M.
Partner: UNT Libraries Government Documents Department

Control of the accumulation of non-process elements and organic compounds in pulp mills with bleach filtrate reuse. Milestones and progress, Quarter 9 (July 1--September 30, 1998)

Description: The two approach changes that were discussed and recommended in the Quarter 8 (April 1--June 30, 1998) progress report have been implemented in the current project plan. The OLI software has been used to develop a preliminary process model for predicting the distribution of NPE`s in a two stage brownstock washer, and the OLI database has been upgraded to include improved chemical equilibrium data for metal-organic interactions. This exercise served as a tool to evaluate the data and methods developed in this study, and to demonstrate its utility to industry. The Weyerhaeuser-NAELS software has also been applied to predicting inorganic solubility behavior. Task C-1.2, Estimation of unavailable thermodynamic parameters (scheduled completion date: 12/97), has been combined with Task D-2.1, Evaluation of the estimation procedure (scheduled completion date: 3/99) with a new scheduled completion date of 8/99. A model for the adsorption of metal ions on wood pulp fibers will include transport effects as well as adsorption equilibrium, and will be combined with a brownstock washer model to evaluate its predictive capability in comparison with mill data, and to demonstrate the applicability of the results obtained in this project. Three tasks are behind schedule: Task A-2.3, Measurement of stability constants for wood organics with metal ions (scheduled completion date: 6/98), Task B-2.1, Measure metal adsorption isotherms on wood pulp (scheduled completion date: 9/97), and Task B-2.3, Measure metal ion adsorption kinetics for strongly adsorbing metal species (scheduled completion date: 3/98). The reasons and expected completion dates are discussed in the Performance Variances and Open Items section. All other tasks are either completed, on, or ahead of schedule.
Date: December 31, 1998
Creator: Frederick, W.J.; Laver, M.L.; Rorrer, G.L.; Rudie, A.W. & Schmidl, W.
Partner: UNT Libraries Government Documents Department

Hydrogen Storage Properties of Lithium Aluminohydride Modified by Dopants and Mechanochemistry

Description: Alkali metal aluminohydrides have high potential as solid hydrogen storage materials. They have been known for their irreversible dehydrogenation process below 100 atm until Bogdanovic et al succeeded in the re-hydrogenation of NaAlH{sub 4} below 70 atm. They achieved 4 wt.% H{sub 2} reversible capacity by doping NaAlH{sub 4} with Ti and/or Fe organo-metallic compounds as catalysts. This suggests that other alkali and, possibly alkaline earth metal aluminohydrides can be used for reversible hydrogen storage when modified by proper dopants. In this research, Zr{sub 27}Ti{sub 9}Ni{sub 38}V{sub 5}Mn{sub 16}Cr{sub 5}, LaNi{sub 4.85}Sn{sub 0.15}, Al{sub 3}Ti, and PdCl{sub 2} were combined with LiAlH{sub 4} by ball-milling to study whether or not LiAlH{sub 4} is capable to both absorb and desorb hydrogen near ambient conditions. X-ray powder diffraction, differential thermal analysis, and scanning electron microscopy were employed for sample characterizations. All four compounds worked as catalysts in the dehydrogenation reactions of both LiAlH{sub 4} and Li{sub 3}AlH{sub 6} by inducing the decomposition at lower temperature. However, none of them was applicable as catalyst in the reverse hydrogenation reaction at low to moderate hydrogen pressure.
Date: June 27, 2002
Creator: Hosokawa, Ketia
Partner: UNT Libraries Government Documents Department

Two-Dimensional Anisotropy in a Layered Metallic Antiferromagnet RE{sub 1-x}Sr{sub x}MnO{sub 3} with x approx.1/2

Description: Some RE{sub 1-x}Sr{sub x}MnO{sub 3} (RE=Nd,Pr) systems with x {approximately} 1/2 exhibit an A-type anti-ferromagnetic (AFM) structure instead of the expectged CE-type magnetic structure. This can be understood as being a consequence of the increase of the band width (W). These A-type magnetic systems also show salient features in their crystal structures. We proposed a two dimensional anisotropy of the transport as well as the magnetic properties for the A-type AFM structure and we show that we have, indeed, observed anisotropic spin wave dispersion relations by inelastic neutron measurements.
Date: July 1, 1997
Creator: Kawano, H.; Yoshizawa, H.; Fernandez-Baca, J.A.; Tomioka, Y. & Kuwahara, H.
Partner: UNT Libraries Government Documents Department

Novel macrocyclic carriers for proton-coupled liquid membrane transport. Final report

Description: The objective of this research program is to elucidate the chemical principles which are responsible for the cation selectivity and permeability of liquid membranes containing macrocyclic carriers. Several new macrocyclic carriers were synthesized during the last three year period. In addition, new, more convenient synthetic routes were achieved for several nitrogen-containing bicyclic and tricyclic macrocycles. The cation binding properties of these macrocycles were investigated by potentiometric titration, calorimetric titration, solvent extraction and NMR techniques. In addition, hydrophobic macrocycles were incorporated into dual hollow fiber and other membrane systems to investigate their membrane performance, especially in the proton-coupled transport mode. A study of the effect of methoxyalkyl macrocycle substituents on metal ion transport was completed. A new calorimeter was constructed which made it possible to study the thermodynamics of macrocycle-cation binding to very high temperatures. Measurements of thermodynamic data for the interaction of crown ethers with alkali and alkaline earth cations were achieved to 473 K. Molecular modeling work was begun for the first time on this project and fundamental principles were identified and developed for the establishment of working models in the future.
Date: August 24, 1996
Creator: Lamb, J.D.; Izatt, R.M.; Bradshaw, J.S. & Shirts, R.B.
Partner: UNT Libraries Government Documents Department

The Adsorption and Reactions of Halogenated Volatile Organic Compounds (VOCs) on Metal Oxides - Final Report

Description: The purpose of this research was to provide a fundamental understanding of the adsorption and catalytic reactions of CCl{sub 4} on metal oxide surfaces with a view to developing strategies for its remediation. The scientific knowledge generated by this project should enable environmental engineers to evaluate the potential of destructive adsorption of CCl{sub 4} and the catalytic reaction of CCl{sub 4} with H{sub 2}O as an alternative for the remediation of carbon tetrachloride. Emphasis was placed on the alkaline earth metal oxides, i.e., MgO, CaO, SrO and BaO because it had previously been demonstrated that MgO and CaO reacted with CCl{sub 4} to form the corresponding metal chloride and carbon dioxide. This process was named destructive adsorption. It was found that the activity toward CCl{sub 4} parallels the basicity of the alkaline earth metal oxide, i.e., the activity decreased in the order BaO>SrO>CaO>MgO. It was found that MgO is active as a catalyst for the reaction of CCl{sub 4} with H{sub 2}O to form CO{sub 2} and HCl. The HCl could be neutralized in aqueous NaOH, and the resulting dilute salt solution could be easily disposed of. Among the alkaline earth oxides, MgO is the only active catalyst at moderate temperatures. Thus, nearly complete removal of CCl{sub 4} can be achieved over a long period. The favorable catalytic activity of MgO relative to the other alkaline earth oxides is attributed to two factors; first, MgO is not as readily converted to MgCl{sub 2}, and, second, the decomposition temperature of MgCO{sub 3} ({approximately}430 C) is substantially less than that of the other carbonates. As a consequence, chloride and carbonate phases do not substantially inhibit the catalytic activity.
Date: November 1, 2000
Creator: Lunsford, J. H.
Partner: UNT Libraries Government Documents Department

Hydrogen Storage Properties of Lithium Aluminohydride Modified by Dopants and Mechanochemistry

Description: Alkali metal aluminohydrides have high potential as solid hydrogen storage materials. They have been known for their irreversible dehydrogenation process below 100 atm until Bogdanovic et al [1, 2] succeeded in the re-hydrogenation of NaAlH{sub 4} below 70 atm. They achieved 4 wt.% H{sub 2} reversible capacity by doping NaAlH{sub 4} with Ti and/or Fe organo-metalic compounds as catalysts. This suggests that other alkali and, possibly alkaline earth metal aluminohydrides can be used for reversible hydrogen storage when modified by proper dopants. In this research, Zr{sub 27}Ti{sub 9}Ni{sub 38}V{sub 5}Mn{sub 16}Cr{sub 5}, LaNi{sub 4.85}Sn{sub 0.15}, Al{sub 3}Ti, and PdCl{sub 2} were combined , LaNi4.85Sn0.15, Al3Ti, and PdCl2 were combined with LiAlH{sub 4} by ball-milling to study whether or not LiAlH{sub 4} is capable to both absorb and desorb hydrogen near ambient conditions. X-ray powder diffraction, differential thermal analysis, and scanning electron microscopy were employed for sample characterizations. All four compounds worked as catalysts in the dehydrogenation reactions of both LiAlH{sub 4} and Li{sub 3}AlH{sub 6} by inducing the decomposition at lower temperature. However, none of them was applicable as catalyst in the reverse hydrogenation reaction at low to moderate hydrogen pressure.
Date: August 1, 2002
Creator: Hosokawa, Keita
Partner: UNT Libraries Government Documents Department

Models for calculation of dissociation energies of homonuclear diatomic molecules

Description: The variation of known dissociation energies of the transition metal diatomics across the Periodic Table is rather irregular like the bulk sublimation enthalpy, suggesting that the valence-bond model for bulk metallic systems might be applicable to the gaseous diatomic molecules and the various intermediate clusters. Available dissociation energies were converted to valence-state bonding energies considering various degrees of promotion to optimize the bonding. The degree of promotion of electrons to increase the number of bonding electrons is smaller than for the bulk, but the trends in bonding energy parallel the behavior found for the bulk metals. Thus using the established trends in bonding energies for the bulk elements, it was possible to calculate all unknown dissociation energies to provide a complete table of dissociation energies for all M/sub 2/ molecules from H/sub 2/ to Lr/sub 2/. For solids such as Mg, Al, Si and most of the transition metals, large promotion energies are offset by strong bonding between the valence state atoms. The main question is whether bonding in the diatomics is adequate to sustain extensive promotion. The most extreme example for which a considerable difference would be expected between the bulk and the diatomics would be that of the Group IIA and IIB metals. The first section of this paper which deals with the alkaline earths Mg and Ca demonstrates a significant influence of the excited valence state even for these elements. The next section then expands the treatment to transition metals.
Date: August 1, 1979
Creator: Brewer, L. & Winn, J.S.
Partner: UNT Libraries Government Documents Department

Radioactivation considerations for the HEB (High Energy Booster) test beams and beam absorbers

Description: The primary locations of radioactivation in the High Energy Booster will be the beam absorbers and in the target-beam dump assembly used for producing the test beams. The purpose of this note will be to make preliminary estimates of the radioactivation of the components of these systems. These will be based, primarily, upon experience gained in the design of Tevatron components. 1 fig., 1 tab.
Date: October 1, 1987
Creator: Cossairt, J.D.
Partner: UNT Libraries Government Documents Department