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Multiheteromacrocycles that complex metal ions. Sixth progress report, 1 May 1979-30 April 1980. [Hemispherands; spherands]

Description: Objective is to design synthesize, and evaluate cyclic and polycyclic host organic compounds for their abilities to complex and lipophilize guest metal ions, their complexes, and their clusters. Host organic compounds consist of strategically placed solvating, coordinating, and ion-pairing sites tied together by covalent bonds through hydrocarbon units around cavities shaped to be occupied by guest metal ions or by metal ions plus their ligands. Specificity in complexation is sought by matching… more
Date: January 15, 1980
Creator: Cram, D. J.
Partner: UNT Libraries Government Documents Department
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Kilowatt Isotope Power System: component report for the Ground Demonstration System Accumulator

Description: The Model Number ORC1A3A01 System Accumulator for the Kilowatt Isotope Power System was expulsion tested and demonstrated to be in compliance with the requirements of Sundstrand Explusion Test Procedure, TP 400. Test requirements of TP 400 were extracted from the Kilowatt Isotope Power System, Ground Demonstration System Test Plan.
Date: January 31, 1978
Creator: Brainard, E.L.
Partner: UNT Libraries Government Documents Department
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Pentamethylcyclopentadienyl and bis(trimethylsilyl)amido complexes of the di- and trivalent lanthanides

Description: The reaction of the divalent iodides YbI/sub 2/ and EuI/sub 2/ with NaN(SiMe/sub 3/)/sub 2/ has provided pentane-soluble, monomeric derivatives of the divalent lanthanides. These compounds are isolated as the solvated species Eu(N(SiMe/sub 3/)/sub 2/)/sub 2/L/sub 2/ (L = thf or 1,2-dme), Yb(N(SiMe/sub 3/)/sub 2/)/sub 2/(thf)/sub 1/ /sub 5/ and Yb(N(SiMe/sub 3/)/sub 2/)/sub 2/L/sub 2/ (L = 1,2-dme or OEt/sub 2/), or as the sodium salts NaM(N(SiMe/sub 3/)/sub 2/)/sub 3/ (M = Eu or Yb). The pentam… more
Date: March 1, 1982
Creator: Tilley, T. D.
Partner: UNT Libraries Government Documents Department
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Cationically polymerizable monomers derived from renewable sources

Description: The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. … more
Date: October 1, 1991
Creator: Crivello, J. V.
Partner: UNT Libraries Government Documents Department
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Facile reaction/extraction of coal with supercritical fluids. Quarterly technical progress report, January 1-March 31, 1984

Description: Arylmethyl phenyl ethers undergo competing reactions when treated with Lewis acids in benzene solvent. Apparently, benzene is insufficiently reactive to compete with intramolecular (intrapolymer) nucleophiles and, consequently, no increase in solubility accompanies the cleavages of ether links upon addition of benzene. When better nucleophiles, naphthalene and phenanthene, are provided, carbonium ions generated from ether cleavages are capped and the product is lower in molecular weight and mor… more
Date: April 20, 1984
Creator: Venier, C. G. & Squires, T. G.
Partner: UNT Libraries Government Documents Department
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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

Description: This report describes progress on research during the eleventh quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal convers… more
Date: 1991-06~
Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.
Partner: UNT Libraries Government Documents Department
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Dynamic shear behavior of alumina-filled epoxy

Description: Thin-walled tubular specimens of alumina-filled epoxy were loaded in torsion at a strain rate of approximately 10/sup 3/ s/sup -1/ using a stored-torque Kolsky bar. In addition to measuring the time resolved shear stress and shear strain in the specimen, the axial stress generated by the dilation of the material during shear deformation was also obtained as a function of time. Tests were conducted at room temperature and at -60/sup 0/C. At room temperature, a moderate amount of plastic deformat… more
Date: March 1, 1982
Creator: Costin, L.S.
Partner: UNT Libraries Government Documents Department
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Mechanisms for radiation damage in DNA. Progress report, January 1, 1982-December 31, 1982

Description: In this project several mechanisms are proposed for radiation damage to DNA constituents and DNA, and a series of experiments utilizing electron spin resonance spectrometry to test the proposed mechanisms have been detailed. In the past studies have concentrated chiefly on the direct effect of radiation on DNA. We are currently investigating irradiated systems of DNA constituents which may shed light on indirect effects. In addition, studies of radiation effects on lipids have been undertaken w… more
Date: May 1, 1982
Creator: Sevilla, M. D.
Partner: UNT Libraries Government Documents Department
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Heavy recycle solvent studies in two-stage coal liquefaction. Final technical report, September 1, 1982-December 30, 1983

Description: The objective of this program has been to study the chemistry of the components with high boiling points in a direct coal liquefaction recycle solvent and to identify those components which lead to higher overall yields and improved product stability in the initial coal dissolution step of direct coal liquefaction processes. The major conclusions are: -454 C recycle solvent is primarily aromatic hydrocarbons (73%) and contains almost no asphaltenes; +454 C recycle solvent is primarily asphalten… more
Date: January 10, 1984
Creator: Longanbach, J. R.
Partner: UNT Libraries Government Documents Department
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Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

Description: The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF)… more
Date: September 1, 1980
Creator: Stille, J. K.
Partner: UNT Libraries Government Documents Department
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Chemical characterization of CTBN (carboxyl-terminated butadiene/acrylonitrile) and its epoxy adduct

Description: This report describes the analysis of carbonxyl-terminated butadiene (CTB), carboxyl-terminated butadiene/acrylonitrile (CTBN), and a CTBN adduct prepared by reaction with Epon 828. Data from gel permeation chromatography, nuclear magnetic resonance spectroscopy, high performance liquid chromatography, and ion chromatography are presented and discussed. Quantitative methods based on carbon-13 and proton NMR for analyzing CTBN are described. Proton NMR was found to be useful in identifying lots … more
Date: January 1, 1990
Creator: Smith, R.E.
Partner: UNT Libraries Government Documents Department
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Effect of water-bearing fiber in Kevlar 49-epoxy composites

Description: Water has been observed to be adsorbed, and possibly absorbed, by desiccated Kevlar 49 fiber to 6 percent of the fiber weight in 100 percent relative humidity. The effect of the water on the transverse flexural strength and elastic modulus of an aliphatic amine-cured epoxy, unidirectionally reinforced with saturated Kevlar 49, has been determined. Such composites are weaker than those made with fiber equilibrated to 0 percent relative humidity, and the effect persists after a 75/sup 0/C, 16-h p… more
Date: January 1, 1978
Creator: Moss, M.
Partner: UNT Libraries Government Documents Department
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Control of catalytic hydrotreating selectivity with ammonia. [Hydrodeoxygenation]

Description: The hydrogenation of naphthalene in the presence of 0, 24, or 48 kPa of ammonia derived from propyl amine was studied during the hydrodeoxygenation (HDO) of dibenzofuran (DBF). A new sample of sulfided NiMo/Al{sub 2}O{sub 3} catalyst at 360{degrees}C, 6.9 MPa total H{sub 2} pressure in a vapor phase tubular reactor was used. As a base-line the HDO of DBF was also studied in the absence of both naphthalene and ammonia. Ammonia inhibited both the HDO of dibenzofuran and the hydrogenation of napht… more
Date: January 1, 1992
Creator: Satterfield, C. N. & Lee, C. M.
Partner: UNT Libraries Government Documents Department
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Hydrogen-Transfer and Charge Transfer in Photochemical and High Energy Radiation Induced Reactions: Effects of Thiols. Final Report, February 1, 1960-January 31, 1979

Description: Absorption of ultraviolet or visible light, or high energy radiation, may lead to highly reactive free radicals. Thiols affect the reactions of these radicals in the following ways: (1) transfer of hydrogen from sulfur of the thiol to a substrate radical, converting the radical to a stable molecule, and the thiol to a reactive thiyl radical; and (2) transfer of hydrogen from a substrate radical or molecule to thiyl, regenerating thiol. The thiol is thus used repeatedly and a single molecule may… more
Date: March 1, 1980
Creator: Cohen, S. G.
Partner: UNT Libraries Government Documents Department
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Fundamental studies of catalytic processing of synthetic liquids

Description: This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We will model the complex type of sulfided Mo catalyst proposed for these reactions with a simple single crystal surfaces that display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques.
Date: April 10, 1990
Creator: Watson, P. R.
Partner: UNT Libraries Government Documents Department
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System for vacuum pouring of epoxy tensile and impact specimens with a study of the behavior of these specimens at 77 K and 293 K

Description: The purpose of the investigation was to establish a suitable technique for vacuum pouring of epoxy test specimens and to study the behavior of these specimens at 77 K and 293 K. A series of tensile and impact tests was conducted using specimens made from the following resins: Epon 828, Epon 871, and Epon curing agent Z. These materials are of general interest to designers of magnets for cryogenic service. Tests of the specimens were carried out at 77 K and 293 K. The 77 K data indicate that ten… more
Date: March 31, 1978
Creator: Fitzpatrick, C.M. & Stoddart, W.C.T.
Partner: UNT Libraries Government Documents Department
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Studies of the surface structures of molecular crystals and of adsorbed molecular monolayers on the (111) crystal faces of platinum and silver by low-energy electron diffraction

Description: The structures of molecular crystal surfaces were investigated for the first time by the use of low-energy electron diffraction (LEED). The experimental results from a variety of molecular crystals were examined and compared as a first step towards understanding the properties of these surfaces on a microscopic level. The method of sample preparation employed, vapor deposition onto metal single-crystal substrates at low temperatures in ultrahigh vacuum, allowed concurrent study of the structure… more
Date: January 1, 1977
Creator: Firment, L.E.
Partner: UNT Libraries Government Documents Department
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Test methods for the dynamic mechanical properties of polymeric materials. Final report

Description: Various test geometries and procedures for the dynamic mechanical analysis of polymers employing a mechanical spectrometer have been evaluated. The methods and materials included in this work are forced torsional pendulum testing of Kevlar/epoxy laminates and rigid urethane foams, oscillatory parallel plate testing to determine the kinetics of the cure of VCE with Hylene MP, oscillatory compressive testing of B-3223 cellular silicone, and oscillatory tensile testing of Silastic E and single Kev… more
Date: June 1, 1980
Creator: Baker, G.K.
Partner: UNT Libraries Government Documents Department
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GC/MS characterization of condensable tars in the output stream of a stirred fixed-bed gasifier

Description: The output stream of the stirred fixed-bed gasifier at the Morgantown Energy Technology Center was sampled for total entrained material. A major portion of the entrained material, in addition to particles, is condensable tar that is subsequently removed from the process gas by wet scrubbing. Characterization of the entrained materials, specifically the tar, is important to establish contaminant levels and to evaluate performance of downstream cleanup units. Samples of tars were collected from t… more
Date: December 1, 1981
Creator: Lamey, S. C.; McCaskill, K. B. & Smith, R. R.
Partner: UNT Libraries Government Documents Department
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Pretreatment of Kapton-coated cable for epoxy adhesion

Description: Preliminary testing of a new system for protecting bonded strain gages that will be attached to the MFTF magnets indicated falling electrical resistance to ground, attributed to the infiltration of moisture. The most likely infiltration route seemed to be along the Kapton lead cable, which has an outer surface of FEP fluorocarbon resin. Samples of the cable were pretreated with a fluorocarbon etchant, Tetra-Etch, for periods of 10, 25, and 40 s at room temperature, followed by rinsing with demi… more
Date: January 9, 1984
Creator: Carley, J. F.
Partner: UNT Libraries Government Documents Department
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Computer programs, to determine credible regions for Weibull distribution

Description: Computer software for analyzing life test data with a Weibull distribution is given. The programs calculate and plot the 95, 90, 50 and 5% highest probability density contours and the maximum likelihood estimators on the same frame for all sets of data. They also calculate the maximum likelihood estimator of mean life and conservative 95, 90, 50 and 5% credible intervals on mean life. The programs are used to analyze data on the lifetimes of Kevlar/Epoxy spherical vessels and the results are gi… more
Date: unknown
Creator: Agrawal, A.
Partner: UNT Libraries Government Documents Department
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