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Laccolith Complexes of Southeastern Utah: Time of Emplacement and Tectonic Setting - Workshop Proceedings

Description: This report summarizes much of the materials presented at the workshop and provides an extensive list of selected references pertaining to geochronology and tectonics of the Colorado Plateau to facilitate further research.
Date: 1998
Creator: Friedman, Jules D. & Huffman, A. Curtis, Jr.
Partner: UNT Libraries Government Documents Department

Investigations Into the Nature of Alkaline Soluble, Non-Pertechnetate Technetium

Description: This report summarizes work accomplished in fiscal year (FY) 2013, exploring the chemistry of a low-valence technetium(I) species, [Tc(CO)3(H2O)3]+, a compound of interest due to its implication in the speciation of alkaline-soluble technetium in several Hanford tank waste supernatants. Various aspects of FY 2013’s work were sponsored both by Washington River Protection Solutions and the U.S. Department of Energy’s Office of River Protection; because of this commonality, both sponsors’ work is summarized in this report. There were three tasks in this FY 2013 study. The first task involved examining the speciation of [(CO)3Tc(H2O)3]+ in alkaline solution by 99Tc nuclear magnetic resonance spectroscopy. The second task involved the purchase and installation of a microcalorimeter suitable to study the binding affinity of [(CO)3Tc(H2O)3]+ with various inorganic and organic compounds relevant to Hanford tank wastes, although the actual measure of such binding affinities is scheduled to occur in future FYs. The third task involved examining the chemical reactivity of [(CO)3Tc(H2O)3]+ as relevant to the development of a [(CO)3Tc(H2O)3]+ spectroelectrochemical sensor based on fluorescence spectroscopy.
Date: November 14, 2013
Creator: Rapko, Brian M.; Bryan, Samuel A.; Chatterjee, Sayandev; Edwards, Matthew K.; Levitskaia, Tatiana G.; Peterson, James M. et al.
Partner: UNT Libraries Government Documents Department

Production and Properties of Ceramic Bodies of Alkaline Earth and Other Refractory Oxides

Description: Report discussing the properties and methods of forming ceramic bodies of alkaline earth and other refractory solids. These materials can be used for "reaction chambers, crucibles for melting metals, casting solids, insulation shields, thermocouple shields and other heat resistant bodies...High calcium lime was found to have the necessary chemical and thermal properties for many of the above uses."
Date: August 1945
Creator: Keller, W. H.; Peterson, David & Handlin, Louis
Partner: UNT Libraries Government Documents Department

Systems Containing Alkali Carbonates, Alkaline Earth Carbonates, and Both

Description: Abstract: "In this report is assembled the available information about the dissociation and melting of the alkali and the alkaline earth carbonates and the binary systems they form with each other. Information is also included about the oxides formed on dissociation of the carbonates, and when it exists pertinent information about the effect of water. Because the carbonates are compounds in binary systems that contain the volatile CO2 component, the report contains a discussion of the complicated phase equilibrium relations in systems in which a compound is formed between volatile and nonvolatile components, including a discussion both of systems in which the solubility curve does not and does intersect the critical curve."
Date: June 1958
Creator: Morey, George W.
Partner: UNT Libraries Government Documents Department

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

Compilation of various fusion methods for the dissolution of insoluble residues

Description: From introduction: "These insoluble residues have also been subjected to a continuous fusion process with sodium bisulfate being used as the flux. The results obtained with this method and a detailed description of the procedure employed have been recorded in two reports."
Date: 1946
Creator: Calkins, Vincent P.
Partner: UNT Libraries Government Documents Department

The Choice of Crops for Alkali Land

Description: "The object of this bulletin is to bring to the attention of owners of alkali land the crop plants which are most likely to give satisfactory results. It can not be too emphatically stated that crop production on such soils is at best precarious. For this reason and because the alkali resistance of plants depends upon many varying conditions, it is impossible to offer more than suggestions as to what crops are best worth trying." -- p. 5-6. Topics discussed include the effects of alkali upon plant growth, plants well-adapted to alkaline soils, and alkali resistance in different types of plants.
Date: 1911
Creator: Kearney, Thomas H. (Thomas Henry), 1874-1956
Partner: UNT Libraries Government Documents Department

Accurate Enthalpies of Formation of Alkali and Alkaline Earth Metal Oxides and Hydroxides: Assessment of the Correlation Consistent Composite Approach (ccCA)

Description: Article on accurate enthalpies of formation of alkali and alkaline earth metal oxides and hydroxides and an assessment of the correlation consistent composite approach (ccCA).
Date: July 12, 2006
Creator: Ho, Dustin S.; DeYonker, Nathan J.; Cundari, Thomas R., 1964- & Wilson, Angela K.
Partner: UNT College of Arts and Sciences

Computational s-Block Thermochemistry with the Correlation Consistent Composite Approach

Description: Article discussing research on computational s-block thermochemistry with the correlation consistent composite approach, which has been shown to accurately compute gas-phase enthalapies of formation for alkali and alkaline earth metal oxides and hydroxides.
Date: October 3, 2007
Creator: DeYonker, Nathan J.; Ho, Dustin S.; Wilson, Angela K. & Cundari, Thomas R., 1964-
Partner: UNT College of Arts and Sciences

Electrodeposition of Molybdenum-Based Coatings from Aqueous Alkaline Solutions for Enhanced Corrosion Resistance

Description: Zn-Mo coatings are very promising environment friendly anticorrosive coatings as replacement materials for cadmium and chromium (VI) based conversion layers. Electrodeposition has become a favorable technique in fabricating coatings due to its low cost, ease of use, and overall experimental control of coating quality. Very little research so far has been done for the electrodeposition of Zn-Mo coatings under alkaline conditions. In this work, Zn and Zn-Mo coatings were electrochemically deposited on stainless steel from an aqueous alkaline citrate solution. An organic compound, vanillin, was added to the electrolyte as a leveling agent for improving interlayer adherence and corrosion resistance of Zn-Mo coatings. Ni-Mo alloys have been known to possess high tensile strength and excellent corrosion protection of steels, and MoTe2 layers have a potential for the application in anticorrosive coatings due to their hydrophobic properties. In this study, MoTe2-Ni-Mo coatings were deposited on stainless steel using both sputtering and electrodeposition methods. These coatings with high corrosion resistance and other desirable properties are in demand in the oil and gas industry since they can protect and thus extend the lifetime of the underlying materials when exposed to aggressive environments. The Zn-Mo and MoTe2-Ni-Mo coatings were evaluated for chemical composition and corrosion behavior using different types of instrumental and electrochemical techniques. The addition of vanillin to the electrolyte did not change the crystalline structure or composition of the Zn-Mo coating, however, the corrosion resistance of the coating was significantly improved by the leveling effect of vanillin during the electrodeposition. The corrosion resistance of the Ni-Mo coating was also enhanced by applying the hydrophobic MoTe2 monolayer on the top surface.
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Date: May 2018
Creator: Zhou, Ting
Partner: UNT Libraries

Response of Desulfovibrio vulgaris to Alkaline Stress

Description: The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).
Date: November 30, 2007
Creator: Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D. et al.
Partner: UNT Libraries Government Documents Department

High-Strength / High Alkaline Resistant Fe-Phosphate Glass Fibers as Concrete Reinforcement

Description: Calcium-iron-phosphate glasses were developed whose chemical durabilities in alkaline solutions (pH 13) were comparable or superior to those of commercial alkaline-resistant (AR) silica-based glasses. However, the tensile strength of Ca-Fe-phosphate fibers, after being exposed to alkaline environments, including wet Portland cement pastes, is lower than that of current AR silicate fibers. Another series of Ca-Fe-phosphate glasses were developed with excellent chemical durability in strong acidic solutions (H2SO4, HF), indicating potential applications where silica-based fibers degrade very quickly, including E-glass. The new Ca-Fe-phosphate glasses can be melted and processed 300 to 500°C lower than silica-based glasses. This offers the possibility of manufacturing glass fibers with lower energy costs by 40-60% and the potential to reduce manufacturing waste and lower gas emissions. It was found that Ca-Fe-phosphate melts can be continuously pulled into fibers depending on the slope of the viscosity-temperature curve and with viscosity ~100 poise, using multi-hole Pt/Rh bushings.
Date: March 31, 2008
Creator: Velez, Mariano
Partner: UNT Libraries Government Documents Department

Base hydrolysis and hydrothermal processing of PBX-9404 explosive

Description: Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The authors also examine products from the subsequent hydrothermal treatment of the base hydrolysate. The gases produced from hydrolysis of PBX-9404 are ammonia, nitrous oxide, and nitrogen. Major aqueous products are sodium formate, acetate, nitrate, and nitrite, but not all carbon products have been identified. Hydrothermal processing of base hydrolysate destroyed up to 98% of the organic carbon in solution, and higher destruction efficiencies are possible. Major gas products detected from hydrothermal processing were nitrogen and nitrous oxide.
Date: April 1, 1995
Creator: Sanchez, J.A.; Flesner, R.L.; Spontarelli, T.; Dell`Orco, P.C. & Kramer, J.F.
Partner: UNT Libraries Government Documents Department

Drainage of Irrigated Lands

Description: Report discussing "the drainage of irrigated lands which have been seriously injured or rendered wholly unproductive by the seepage of irrigation water or by the rise of alkali, or by both combined.... This report not only describes the condition of the land, the details of its draining, and the results which were obtained in particular cases, but gives carefully drawn deductions from the experiments, together with directions for draining lands which have become too wet or too alkaline under the ordinary methods of irrigation for profitable cultivation. Methods of draining are not so well established for irrigated land as for land in humid areas, which fact suggests the propriety of describing methods that have been tested in specific cases." -- p. 2
Date: 1909
Creator: Brown, Charles F.
Partner: UNT Libraries Government Documents Department

2011 Alkaline Membrane Fuel Cell Workshop Final Report

Description: A workshop addressing the current state-of-the-art in alkaline membrane fuel cells (AMFCs) was held May 8-9, 2011, at the Crystal Gateway Marriott in Arlington, Virginia. This workshop was the second of its kind, with the first being held December 11-13, 2006, in Phoenix, Arizona. The 2011 workshop and associated workshop report were created to assess the current state of AMFC technology (taking into account recent advances), investigate the performance potential of AMFC systems across all possible power ranges and applications, and identify the key research needs for commercial competitiveness in a variety of areas.
Date: February 1, 2012
Creator: Pivovar, B.
Partner: UNT Libraries Government Documents Department

Improvements in geothermometry. Final technical report. Rev

Description: Alkali and alkaline earth geothermometers are useful for estimating geothermal reservoir temperatures, though a general theoretical basis has yet to be established and experimental calibration needs improvement. Equilibrium cation exchange between feldspars provided the original basis for the Na-K and Na-K-Ca geothermometers (Fournier and Truesdell, 1973), but theoretical, field and experimental evidence prove that neither equilibrium nor feldspars are necessary. Here, evidence is summarized in support of these observations, concluding that these geothermometers can be expected to have a surprisingly wide range of applicability, but that the reasons behind such broad applicability are not yet understood. Early experimental work proved that water-rock interactions are slow at low temperatures, so experimental calibration at temperatures below 150/sup 0/ is impractical. Theoretical methods and field data were used instead for all work at low temperatures. Experimental methods were emphasized for temperatures above 150/sup 0/C, and the simplest possible solid and solution compositions were used to permit investigation of one process or question at a time. Unexpected results in experimental work prevented complete integration of the various portions of the investigation.
Date: August 1, 1982
Creator: Potter, J.; Dibble, W.; Parks, G. & Nur, A.
Partner: UNT Libraries Government Documents Department

Cause of pitting in beryllium

Description: Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of the pattern is attributed to these voids and etching out of fines and associated impurities. Hot isostatic pressing with a subsequent heat treatment close residual porosity and dispersed impurities enough to correct the problem.
Date: April 16, 1982
Creator: Kershaw, R.P.
Partner: UNT Libraries Government Documents Department

Detecting Molecular Properties by Various Laser-Based Techniques

Description: Four different laser-based techniques were applied to study physical and chemical characteristics of biomolecules and dye molecules. These techniques are liole burning spectroscopy, single molecule spectroscopy, time-resolved coherent anti-Stokes Raman spectroscopy and laser-induced fluorescence microscopy. Results from hole burning and single molecule spectroscopy suggested that two antenna states (C708 & C714) of photosystem I from cyanobacterium Synechocystis PCC 6803 are connected by effective energy transfer and the corresponding energy transfer time is {approx}6 ps. In addition, results from hole burning spectroscopy indicated that the chlorophyll dimer of the C714 state has a large distribution of the dimer geometry. Direct observation of vibrational peaks and evolution of coumarin 153 in the electronic excited state was demonstrated by using the fs/ps CARS, a variation of time-resolved coherent anti-Stokes Raman spectroscopy. In three different solvents, methanol, acetonitrile, and butanol, a vibration peak related to the stretch of the carbonyl group exhibits different relaxation dynamics. Laser-induced fluorescence microscopy, along with the biomimetic containers-liposomes, allows the measurement of the enzymatic activity of individual alkaline phosphatase from bovine intestinal mucosa without potential interferences from glass surfaces. The result showed a wide distribution of the enzyme reactivity. Protein structural variation is one of the major reasons that are responsible for this highly heterogeneous behavior.
Date: August 3, 2007
Creator: Hsin, Tse-Ming
Partner: UNT Libraries Government Documents Department