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Experimental Determination of Thermodynamic Properties of Ion-Exchange in Heulandite: Binary Ion-Exchange Experiments at 55 and 85 oC Involving Ca2+, Sr2+, Na+, and K+

Description: Heulandite is a common rock-forming zeolite that exhibits wide solid solution of extra framework cations, presumably due to ready ion exchange with aqueous solutions. In order to provide a quantitative basis for interpreting and predicting the distribution of aqueous species between heulandite and aqueous solutions, ion exchange equilibrium between heulandite and aqueous solutions with respect to the binary cation pairs Ca{sup 2+} - K{sup +}, Ca{sup 2+} - Na{sup +}, K{sup +} - Na{sup +}, K{sup … more
Date: April 26, 2004
Creator: Fridriksson, T.; Neuhoff, P. S.; Viani, B. E. & Bird, D. K.
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Partner: UNT Libraries Government Documents Department
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Investigation of lithiated carbons by transmission electron microscopy and x-ray diffraction analysis

Description: The microstructures of lithiated synthetic graphite and carbon black were studied by high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) analysis. Information about the crystal structure of carbon containing various Li compositions can provide useful insights to our understanding of the Li storage mechanism in carbonaceous materials. Samples with compositions of Li{sub 0.93}C{sub 6} or Li{sub 0.45}C{sub 6} were found to contain both stage-one and stage-two compo… more
Date: October 26, 2000
Creator: Tran, T D; Song, X Y & Kinoshita, K
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Partner: UNT Libraries Government Documents Department
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Y-12 Development Organization technical progress report: Part 3 -- Metal processing, period ending March 1, 1994

Description: As part of the effort to downsize its uranium processing facilities, the Y-12 Plant has supported an investigation to identify extraction solvents that would both work efficiently in centrifugal contactors and be disposed of easily. Various organic ethers, hydroxy ethers, ether ketones, acids, amides, and diketones were studied for their ability to extract uranyl nitrate from aqueous solutions. Although many of these solvents were obtained commercially, others had to be synthesized in-house. Th… more
Date: May 26, 1994
Creator: Northcutt, W. G. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Human Vitamin B12 Absorption and Metabolism are Measured by Accelerator Mass Spectrometry Using Specifically Labeled 14C-Cobalamin

Description: There is need for an improved test of human ability to assimilate dietary vitamin B{sub 12}. Assaying and understanding absorption and uptake of B{sub 12} is important because defects can lead to hematological and neurological complications. Accelerator mass spectrometry (AMS) is uniquely suited for assessing absorption and kinetics of {sup 14}C-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of carbon-14 ({sup 14}C) in microliter … more
Date: January 26, 2006
Creator: Carkeet, C.; Dueker, S. R.; Lango, J.; Buchholz, B. A.; Miller, J. W.; Green, R. et al.
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Partner: UNT Libraries Government Documents Department
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Recent Advances in Modeling Hugoniots with Cheetah

Description: We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have be… more
Date: July 26, 2005
Creator: Glaesemann, K R & Fried, L E
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Partner: UNT Libraries Government Documents Department
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Molecular bond selective x-ray scattering for nanoscale analysisof soft matter

Description: We introduce a new technique using resonant soft x-ray scattering for characterizing heterogeneous chemical structure at nanometer length scales in polymers, biological material, and other soft matter. Resonant enhancements bring new contrast mechanisms and increased sensitivity to bridge a gap between bond-specific contrast in chemical sensitive imaging and the higher spatial resolution of traditional small-angle scattering techniques. We illustrate sensitivity to chemical bonding with the res… more
Date: May 26, 2005
Creator: Mitchell, G. E.; Koprinarov, I.; Landes, B. G.; Lyons, J.; Kern, B. J.; Devon, M. J. et al.
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Partner: UNT Libraries Government Documents Department
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Method for spectrochemical analysis using time-resolved laser-induced breakdown. [Patent application]

Description: A method for real-time elemental analysis using laser-induced breakdown of the material under investigation and spectroscopic analysis of the light emitted from the plasma consequently formed is described. By delaying the observation of the emitted radiation, the unwanted background continuum and line spectra from excited ionic species can be rendered unimportant relative to the excited atomic line spectra, thereby producing sharp, well-defined characteristic identifying atomic spectral feature… more
Date: January 26, 1982
Creator: Loree, Thomas R. & Radziemski, Leon J.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Development of advanced technologies for photochemical tritium recovery. Bi-quarterly progress report, January 1, 1982-June 30, 1982

Description: Mixtures of CTCl/sub 3//CDCl/sub 3/ were successfully detritiated by 12..mu.. laser multiple-photon dissociation. The lower limit of the T/D enrichment factor was determined to be approx. 165. Additional studies concerning the effects of pulse energy, irradiation geometry and sample pressure were conducted. Characterization of both untuned and tuned NH/sub 3/ laser configurations were completed. Further laser studies considered implementation of a short pulse CO/sub 2/ laser pump source for eit… more
Date: July 26, 1982
Creator: Aldridge, F. T.; Herman, I. P.; Magnotta, F.; Maienschein, J. L.; Marling, J. B. & Young, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of high-temperature UV-VIS-NIR spectroscopy for the measurement of free energies of complexation at elevated temperatures

Description: We have developed instrumentation capable of measuring optical absorption spectra over a wavelength range of 200--1200 nm and a temperature range of 20--100{degree}C. This fiber-optic based spectrometer generates data which allow the computation of metal-ligand equilibrium constants. Studies at five temperatures have been completed using praseodymium-diglycolate as a model system. Fundamental thermodynamic values (free energies, enthalpies, entropies) were obtained from the experimentally-deter… more
Date: September 26, 1990
Creator: Robouch, P.; Grant, P.; Torres, R. A.; Baisden, P. A. & Silva, R. J.
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Partner: UNT Libraries Government Documents Department
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Organometallic Chemistry of Carbon Dioxide. Final Report for June 1, 1986 - March 31, 2002

Description: Research focused on C{sub 1} transition metal complexes that are relevant to CO{sub 2} activation and fixation. First, we prepared and studied new metallocarboxylic acids, a class of compounds proposed as intermediates in the Water Gas Shift reaction and CO{sub 2} reductions, and the corresponding metallocarboxylate anions. Next, we prepared and structurally characterized a large number of CO{sub 2}-bridged bimetallic compounds (models for metal surface-bound CO{sub 2}) and established structur… more
Date: September 26, 2002
Creator: Gibson, D. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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IN-SITU Chemical Oxidation of Chlorinated Hydrocarbons in the Presence of Radionuclides

Description: Treatability testing for In Situ Chemical Oxidation was conducted on a site where the groundwater was contaminated with trichloroethylelne, nitroaromatics, nitrate, and radionuclides. The treatability testing involved characterization of the contaminated aquifer material and groundwater, soil oxidant demand testing, and batch slurry reaction tests. The aquifer oxidant demand was 0.44 to 0.89 grams KMnO4 per kg aquifer solids. This is an exceptionally low level and indicates that permanganate re… more
Date: February 26, 2003
Creator: Root, D. K.
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Partner: UNT Libraries Government Documents Department
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MALDI analysis of estane degradation

Description: SEUMALDI has been successfully used to accurately measure the MW of hydrolysis degradation products from Estane 5703. Reasonable structure assignments have been made to the degradation products and several observations reported. Most of the low MW degradation peaks have been identified as ester hydrolysis fragments. The data suggest that the polyester macrodiol may be shorter than the {approximately}2000 amu reported by the manufacturer. Experiments are ongoing to determine if hydrolysis occurs… more
Date: March 26, 1999
Creator: Haining, Helen Ji; Kober, E. M.; LeMay, James D.; Mays, Jimmy; Nonidez, William; Overturf, George E., III et al.
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Partner: UNT Libraries Government Documents Department
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Collaborative study of an anion exchange method for the determination of trace plutonium in water

Description: A single-laboratory evaluation and an interlaboratory collaborative study were made of a method for determining plutonium in water. The method was written for the analysis of one-liter samples and involves coprecipitation, acid dissolution, anion exchange, electrodeposition, and alpha pulse height analysis. After the single-laboratory evaluation of the selected method, four samples were prepared for the collaborative study: two river-water samples, a substitute ocean water sample, and sample co… more
Date: June 26, 1978
Creator: Bishop, Carl T.; Glosby, Antonia A. & Phillips, Charles A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Microsensor and Micro-Instrument Technology at Sandia National Laboratories

Description: Important factors in the application of chemical sensing technology to space applications are low mass, small size, and low power. All of these attributes are enabled by the application of MEMS and micro-fabrication technology to chemical sensing. Several Sandia projects that apply these technologies to the development of new chemical sensing capabilities with the potential for space applications will be described. The Polychromator project is a joint project with Honeywell and MIT to develop a… more
Date: March 26, 1999
Creator: Butler, M. A.; Frye-Mason, G. C.; Hughes, R. C. & Osbourn, G. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Plutonium measurements by accelerator mass spectrometry at LLNL

Description: Mass spectrometric methods provide sensitive, routine, and cost-effective analyses of long-lived radionuclides. Here the authors report on the status of work at Lawrence Livermore National Laboratory (LLNL) to develop a capability for actinide measurements by accelerator mass spectrometry (AMS) to take advantage of the high potential of AMS for rejection of interferences. This work demonstrates that the LLNL AMS spectrometer is well-suited for providing high sensitivity, robust, high throughput… more
Date: October 26, 1999
Creator: McAninch, J E; Hamilton, T F; Broan, T A; Jokela, T A; Knezovich, T J; Ognibene, T J et al.
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Partner: UNT Libraries Government Documents Department
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New prediction-augmented classical least squares (PACLS) methods: Application to unmodeled interferents

Description: A significant improvement to the classical least squares (CLS) multivariate analysis method has been developed. The new method, called prediction-augmented classical least squares (PACLS), removes the restriction for CLS that all interfering spectral species must be known and their concentrations included during the calibration. The authors demonstrate that PACLS can correct inadequate CLS models if spectral components left out of the calibration can be identified and if their spectral shapes c… more
Date: January 26, 2000
Creator: HAALAND,DAVID M. & MELGAARD,DAVID K.
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Partner: UNT Libraries Government Documents Department
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Method of Dehalogenation using Diamonds

Description: A method for preparing olefins and halogenated olefins is provided comprising contacting halogenated compounds with diamonds for a sufficient time and at a sufficient temperature to convert the halogenated compounds to olefins and halogenated olefins via elimination reactions.
Date: February 26, 1999
Creator: Farcasiu, Malvina; Kaufman, Phillip B.; Ladner, Edward P. & Anderson, Richard R.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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A novel synthesis of polyesters containing hexa-(tert-butylhydroquinone)cyclotriphosphazene

Description: The majority of polyphosphazene material research has concentrated on the linear polymer configuration. However, this represents only one of three potential backbone configurations for phosphazenes. Linear polymers are formed either directly from phosphorus and nitrogen containing precursors or from the ring opening polymerization of hexachlorocyclotriphosphazene. Two other backbone structures can be formed from hexachlorocyclotriphosphazene cyclolinear and cyclomatrix. Cyclolinear are the leas… more
Date: March 26, 2000
Creator: Stewart, F. F.; Luther, T. A.; Harrup, M. K. & Lash, R. P.
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Partner: UNT Libraries Government Documents Department
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Windows Calorimeter Control (WinCal) program computer software test plan

Description: This document provides the information and guidelines necessary to conduct all the required testing of the Windows Calorimeter Control (WinCal) system. The strategy and essential components for testing the WinCal System Project are described in this test plan. The purpose of this test plan is to provide the customer and performing organizations with specific procedures for testing the specified system's functions.
Date: March 26, 1997
Creator: Pertzborn, N.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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