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Carbon-13-carbon-13 Coupling Constants in Fluorene and O-Methylbenzene Derivatives

Description: A model system to calculate single-path coupling constant was devised to see if the couplings are additive in a system which has a dual-pathway. The system chosen was o-methyl-13C-benzoic acid. Because of anomalies in the data, the series was extended. Hybridization of the label appeared to have relatively little effect, and the conformation of the substituents very important.
Date: August 1977
Creator: Kattner, Richard M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Boron-Carbon System: Quarterly Report Number 2, August - October 1960

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Additional baron-carbon alloys have been prepared by sintering and arc-melting compacts prepared from boron and high-purity graphite. Metallographic examinations of these alloys are in agreement with alloys previously preapred from lampblack. X-ray investigation of sintered compacts indicates that the solubility range of boron carbide… more
Date: November 8, 1960
Creator: Elliott, Rodney P. & Van Thyne, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Boron-Carbon System: Quarterly Report Number 3, November 1960 - January 1961

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. On the basis of metallographic and X-ray diffraction studies it is concluded that boron carbide has a range of solubility from approximately 10 to 20 atomic per cent carbon at 1500 degrees to 2000 degrees Celsius. The melting point of the carbide-graphite eutectic has been established as 2325-2350 degrees Celsius. No reversible allotr… more
Date: February 6, 1961
Creator: Elliott, Rodney P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Boron-Carbon System: Final Technical Report, May 1, 1960 - April 30, 1961

Description: Abstract: The boron-carbon equilibrium diagram has been determined by X-ray, metallographic, and thermal analysis of sintered and arc-cast alloys. A single carbide having a range of solubility from approximately 9 to 20 a/o carbon and melting congruently exists in the system. The terminal solubility of carbon in boron is 0.1-0.2a/o. The freezing reaction at the composition and melting temperature of elemental boron; there is a eutectic reaction at 29a/o carbon and 2375 degrees Celcius. No allot… more
Date: June 7, 1961
Creator: Elliott, Rodney P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Boron-Carbon System: Quarterly Report Number 1, May - June 1960

Description: Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Alloys are being produced by sintering pressed powder aggregates with subsequent arc melting. Alloys have been made at two atomic percent intervals up to thirty atomic per cent carbon. In the future, higher carbon compositions are to be investigated. Techniques have been worked out for the metallographic preparation of the extremely h… more
Date: August 5, 1960
Creator: Elliott, Rodney P. & Van Thyne, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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X-ray Analysis of the Uranium-Carbon System

Description: The following report includes an account of the X-ray structures of all he uranium-carbides together with X-ray data on the solid solubilities of these carbides with each other and with uranium and carbon.
Date: 1948
Creator: Rundle, R. E.; Wilson, A. S. & Baenziger, Norman C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oxygen Quenching Errors in Liquid Scintillation Counting of C14O2 Following Schoniger Flask Combustion

Description: Kalberer and Rutschmann (Helv, Chim, Act, 44 : 1956, 1961) described a method of estimating quantitatively C-14 compounds on a paper carrier, for example chromatograms. The sample is combusted in oxygen, the C14O2 produced being absorbed in ethanolamine solution and counted by liquid scintillation techniques. However, errors occur where there are deviations from their experimental conditions, such as in counting equipment or weight combusted, owing to differing concentrations of dissolved oxyge… more
Date: September 1963
Creator: Matthews, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Niobium Phase Diagrams : Manuscript Report on Niobium-Carbon System

Description: Abstract: "The niobium-carbon system has been determined by X-ray and metallographic examination of sintered and arc-cast alloys. Two carbides exist: hexagonal Nb2C with a limited range of homogeneity, and cubic NbC with a solubility range from 8.25 to 10.25 weight per cent carbon. Dilute alloys freeze by eutectic reaction at 2230 C. The solubility of carbon in niobium is 0.80 at the eutectic temperature, but this decreases rapidly with temperature. Metallographic evidence indicates a peritecti… more
Date: May 6, 1959
Creator: Elliott, Rodney P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular Basis of Microbial One-Carbon Metabolism

Description: The Gordon Research Conference (GRC) on Molecular Basis of Microbial One-Carbon Metabolism was held at Connecticut College, New London, Connecticut. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Date: July 12, 2002
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Carbon Flux in Reservoir Sediments

Description: The central objective of the study was to fractionate sedimenting organic materials according to their source (allochthonous or autochthonous) and ultimately to determine the degree of biodegradability of contributions from either source with particular reference to activities at the mud-water interface.
Date: May 1973
Creator: Newton, Charles Eugene
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Qualification Approval Tests on resistance products Co.`s type {open_quotes}H{close_quotes} Carbon Composition resistors (0.2 and 40 Megohm)

Description: Engineering Work Requests ESE-48 & 49 established a program for performance of Qualification Approval Tests on RPC`s 0.2 and 40 meghom Carbon Composition Resistors. This report is an accounting of these tests wherein (50) samples of each component were subjected to QA tests per drawings 8O2C250 and 802C251. Tests are explained and results tabulated.
Date: March 25, 1960
Creator: Dixon, L.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A theoretical study of a carbon lattice system for lithium intercalated carbon anodes

Description: A theoretical study was performed using computational chemistry to describe the intermolecular forces between graphite layers as well as spacing and conformation. It was found that electron correlation and a diffuse basis set were important for this calculation. In addition, the high reactivity of edge sites in lithium intercalated carbon anodes was also investigated. In this case, the reactive sites appear to strongly correlate with the relative distribution of the total atomic spin densities … more
Date: September 1, 1997
Creator: Scanlon, L. G.; Storch, D. M.; Newton, J. H. & Sandi, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability of eutectic interface during directional solidification

Description: Directional solidification of eutectic alloys shows different types of eutectic morphologies. These include lamellar, rod, oscillating and tilting modes. The growth of these morphologies occurs with a macroscopically planar interface. However, under certain conditions, the planar eutectic front becomes unstable and gives rise to a cellular or a dendritic structure. This instability leads to the cellular/dendritic structure of either a primary phase or a two-phase structure. The objective of thi… more
Date: April 23, 1996
Creator: Han, S.H.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Chemical Evolution and the Origin of Life

Description: The formation of more complex carbon compounds from simple ones through the action of radiation is used in an interpretation of the original formation of such compounds on earth. The relation of plants and animals and evolution of photosynthesis is discussed in the light of the participation of sulfur compounds in the metabolism of both group.
Date: March 10, 1953
Creator: Calvin, Melvin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimation of brassylic acid by gas chromatography-mass spectrometry

Description: The main focus of this work is to estimate Brassylic Acid (BA) using gas chromatography-mass spectrometry (GC-MS). BA is a product obtained from the oxidative cleavage of Erucic Acid (EA). BA has various applications for making nylons and high performance polymers. BA is a 13 carbon compound with two carboxylic acid functional groups at the terminal end. BA has a long hydrocarbon chain that makes the molecule less sensitive to some of the characterization techniques. Although BA can be characte… more
Date: October 29, 2010
Creator: Mohammed J. Nasrullah, Erica N. Pfarr, Pooja Thapliyal, Nicholas S. Dusek, Kristofer L. Schiele, Christy Gallagher-Lein, and James A. Bahr
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Chemistry Thesis] Part 2: High Intensity Light Sources

Description: A stable carbon arc operated in controlled atmosphere is described. The arc was designed to serve as a light source during lifetime studies of the B/sup 2/ SIGMA state of the CN molecule. The CN radiation from the plasma of the arc was investigated and found to have a brightness temperature of 5500 icient laborato K at lambda 3883 A. This is considerably higher than an estimate of the value required for lifetime measurements. The stability of the carbon arc under various conditions is discussed… more
Date: October 9, 1958
Creator: Worden, Earl Fremont, Jr.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Inelastic neutron studies of the low energy phonon excitations in the RENi{sub 2}B{sub 2}C superconductors (RE=Lu,Y,Ho,Er)

Description: We studied the low-energy phonon excitations for wavevectors close to the Fermi surface nesting vector {xi}{sub m} = 0.55 a vector. We find that above T{sub c} the frequencies of the {Delta}{sub 4} [{zeta}00] lowest-lying optical and acoustic phonon modes decrease with decreasing temperature, for {xi} close to {xi}{sub m}, and there is a shift of intensity from the upper to the lower mode, an effect characteristic of coupled modes. From approximately 120K down to temperatures in the vicinity of… more
Date: August 1, 1997
Creator: Bullock, M.; Stassis, C.; Zarestky, J.; Goldman, A.; Canfield, P.; Shirane, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Anisotropic superconducting and normal state magnetic properties of single crystals of RNi*2*B*2*C compounds (R = Y, Gd, Dy, Ho, Er, and Tm)

Description: The interaction of superconductivity with magnetism has been one of the most interesting and important phenomena in solid state physics since the 1950`s when small amounts of magnetic impurities were incorporated in superconductors. The discovery of the magnetic superconductors RNi{sub 2}B{sub 2}C (R = rare earth, Y) offers a new system to study this interaction. The wide ranges of superconducting transition (T{sub c}) and antiferromagnetic (AF) ordering temperatures (T{sub N}) (0 K {le} T{sub … more
Date: November 1, 1995
Creator: Cho, B.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Multicomponent-Multiphase Equation of State for Carbon

Description: The unique properties of carbon have made it both a fascinating and an important subject of experimental and theoretical studies for many years [1]-[4]. The contrast between its best-known elemental forms, graphite and diamond, is particularly striking. Graphite is black, has a rather low density and high compressibility (close to that of magnesium), and is greasy enough to be useful as a lubricant and in pencil leads. Diamond is brilliantly translucent, 60% more dense than graphite, less compr… more
Date: September 1, 2001
Creator: KERLEY, GERALD IRWIN & CHHABILDAS, LALIT C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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METHODS FOR THE ANALYSIS OF BERYLLIUM CARBIDE

Description: Analytical methods are given for determining the composition and impurities of beryllium carbide. A summary of the experimental work leading to these procedures and supporting data are also presented. Analytical procedures for the determination of free and combined carbon, moisture, nitrogen, beryllium oxide, silica, iron, total beryllium, and beryllium metal are outlined. Diagrams of special apparatus used are included. (auth)
Date: March 21, 1949
Creator: Bridges, W.L.; Funston, E.S. & Reed, S.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reduction of Carbon Dioxide inAqueous Solutions by IonizingRadiation

Description: The question of the conditions under which living matter originated on the surface of the earth is still a subject limited largely to speculation. The speculation has a greater chance of approaching the truth insofar as it includes and is based upon the ever wider variety of established scientific fact. One of the purposes of the herein reported observation was to add another fact to the ever increasing information which might have any bearing upon this most interesting question. It is not our … more
Date: March 13, 1951
Creator: Garrison, W. M.; Morrison, D. C.; Hamilton, J. G.; Benson, A. A. & Calvin, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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