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Investigations of Thermochemistry and the Kinetics of H Atom Radical Reactions

Description: The thermochemistry of several species, and the kinetics of various H atom radical reactions relevant to atmospheric and combustion chemistry were investigated using ab initio theoretical techniques and the flash photolysis / resonance fluorescence technique. Using ab initio quantum mechanical calculations up to the G3 level of theory, the C-H bond strengths of several alkanes were calculated. The bond strengths were calculated using two working reactions. From the results, it is apparent that … more
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Date: December 2002
Creator: Peebles, Lynda Renee
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Kinetic studies and computational modeling of atomic chlorine reactions in the gas phase.

Description: The gas phase reactions of atomic chlorine with hydrogen sulfide, ammonia, benzene, and ethylene are investigated using the laser flash photolysis / resonance fluorescence experimental technique. In addition, the kinetics of the reverse processes for the latter two elementary reactions are also studied experimentally. The absolute rate constants for these processes are measured over a wide range of conditions, and the results offer new accurate information about the reactivity and thermochemi… more
Date: August 2009
Creator: Alecu, Ionut M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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General method for computation of equilibrium composition and temperature of chemical reactions

Description: Report presenting an approximation process that can be used to determine both composition and temperature resulting from a chemical reaction. It is suitable for use with any set of reactants over the complete range of mixture ratios as long as the products of reaction are ideal gases.
Date: June 1950
Creator: Huff, Vearl N. & Morrell, Virginia E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The synthesis of methylenecyclobutane, spiropentane, and 2-methyl-1-butene from pentaerythrityl tetrabromide

Description: From Summary: "Reduction of pentaerythrityl tetrabromide in ethanol with zinc in the presence of sodium carbonate and sodium iodide was found to yield methylenecyclobutane, spiropentane, and 2-methyl-l-butene. Yields were 46 percent methylenecyclobutane, 21 percent spiropentane, and 12 percent 2-methyl-l-butene. The reduction procedure described offers a method of preparing both methylenecyclobutane and spiropentane from the same reaction in yields comparable with individual methods of synthesi… more
Date: February 1946
Creator: Slabey, Vernon A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reactions with steel of compounds containing chemical groups used in lubricant additives

Description: Report presenting an investigation of the chemical reactions between steel of a type used in aircraft-engine cylinder barrels and compounds containing reactive groups commonly found in lubricant additives. The products formed by reaction at temperatures from 400 to 650 degrees F were analyzed by reflection electron diffraction. Results regarding the diffraction patterns, a description of the products found, and correlation of the results with results form other investigations are provided.
Date: February 1947
Creator: Powell, Allen S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further Studies of the Mechanism by Which Hydrogen Enters Metals During Chemical and Electrochemical Processing

Description: Note presenting studies of the entry of hydrogen into metals from chemical and electrochemical action, which occurs when hydrogen-metal alloy formation is simultaneous with discharge (or release) of hydrogen atoms. Results of some new experimental investigations and some correlations with other studies are provided.
Date: March 1954
Creator: McGraw, L. D.; Ditmars, W. E.; Snavely, C. A. & Faust, C. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Preparation of 2, 2, 4, 4-Tetramethylpentane

Description: Report presenting seven distinct operations in the preparation of 2,2,4,4-tetramethylpentane, including the preparation of di-isobutylene hydrochloride, preparation of dimethylzinc, reaction of dimethylzinc in dry benzene with di-isobutylene hydrochloride, preliminary distillation of the reaction products, treatment of the first distillate with sodium and alcohol, final distillation after appropriate washing of the products, and recovery of the iodine in the zinc residues of II as methyl iodide. more
Date: May 1942
Creator: Drake, N. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Researches on Preliminary Chemical Reactions in Spark-Ignition Engines

Description: "Chemical reactions can demonstrably occur in a fuel-air mixture compressed in the working cylinder of an Otto-cycle (spark ignition) internal-combustion engine even before the charge is ignited by the flame proceeding from the sparking plug. These are the so-called "prelinminary reactions" ("pre-flame" combustion or oxidation), and an exact knowledge of their characteristic development is of great importance for a correct appreciation of the phenomena of engine-knock (detonation), and conseque… more
Date: June 1943
Creator: Mühlner, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rate of reaction of gaseous fluorine with water vapor at 35 degrees C

Description: Report presenting testing of fluorine and water vapor, which react extremely slowly or not at all in the gas phase at 35 degrees Celsius at partial pressures of the reactants up to 40 mm of mercury. Results regarding the gross nature of the reaction, order of the reaction, kinetics of surface and gas-phase reactions, relative importance of surface and gas-phase reactions, and rate of surface reaction are provided.
Date: September 1958
Creator: Slabey, Vernon A. & Fletcher, Edward A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental Evidence for Heavy-Atom Tunneling in the Ring-Opening of Cyclopropylcarbinyl Radical from Intramolecular 12C/13C Kinetic Isotope Effects

Description: Article on experimental evidence for heavy-atom tunneling in the ring-opening of cyclopropylcarbinyl radical from intramolecular 12C/13C kinetic isotope effects.
Date: August 19, 2010
Creator: Gonzalez-James, Ollie M.; Zhang, Xue; Datta, Ayan; Hrovat, David A.; Singleton, Daniel A. & Borden, Weston T.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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The Mercury-Sensitized Photo-Reactions of 2,3-Dimethyl Butane

Description: The work encompassed by this thesis is partially a reproduction of the results obtained by John A. Marcia in his work on the photo-chemical reactions of branched hydrocarbons. The previous work done on this particular problem was rendered partially valueless because of the loss of the liquid hydrocarbon product when a fractionation column at the Texas Company Laboratory, Beacon, New York, broke during the fractionation run.
Date: 1947
Creator: Sutton, Cecil C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Ketene Reactions: I. The Addition of Acid Chlorides to Dimethylketene ; II. The Cycloaddition of Ketenes to Carbonyl Compounds

Description: Part I describes the addition of several acid chlorides to dimethylketene. The resulting 3-ketoacid chlorides were isolated and characterized. Part II describes the cycloaddition of several aldoketenes to chloral. The ketenes were generated in situ by dehydrohalogenation and dehalogenation of appropriately substituted acyl halides.
Date: December 1970
Creator: Smith, Larry
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Thermodynamic Calculations Relating to Chloride Volatility Processing of Nuclear Fuels: [Part] 2. The Capacity of Chlorine for Transporting Plutonium Tetrachloride Vapor During Reaction of U3O8-PuO2 with Carbon Tetrachloride

Description: Report issued by the Oak Ridge National Laboratory discussing thermodynamic calculations of nuclear fuels. As stated in the introduction, "the equations developed in this report could be used to calculate the capacity of chlorine for transporting plutonium tetrachloride" (p. 2). This report includes tables, and illustrations.
Date: October 1964
Creator: Gens, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preparation and Stereochemistry of Reactive Intermediates Containing a Silicon-Carbon Double Bond

Description: 1,1-Dimethyl-2-neopentylsilene reacted with the N-methylimine of benzophenone to give 1,2,2-trimethyl-3- neopentyl-4,4-diphenyl-l-aza-2-silacyclobutane, I, and 2,3,4,4a-tetrahydro-2,3,3-trimethyl-1-phenyl-4-neopentyl-2- aza-3-silanephthalene, II, in 35% and 20% yields, respectively. Compounds I and II did not serve as thermal silene precursors. Heating I and II to over 280°C did not yield 1,3-disilacyclobutanes. In the presence of 2,3- dimethyl-1,3-butadiene typical silene products were not obt… more
Date: December 1991
Creator: Uang, Shinian
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Photosynthesis

Description: Encyclopedia article entry in the Encyclopedia of Time: Science, Philosophy, Theology, and Culture by H. James Birx. This encyclopedia article discusses photosynthesis.
Date: 2009
Creator: O'Toole, Erin
Item Type: Refine your search to only Text
Partner: UNT Libraries
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The Influence of Selected Non-Bonded Interactions on Vicinal Carbon-Carbon Coupling Constants

Description: The body of information concerning carbon-carbon spin-spin coupling constants now includes a large number of coupling constants, the establishment of a dihedral angular dependence on 3JCC, and the application of 3JCC to conformational analysis. This study adds another dimension to the growing wealth of information associated with 13 C-NMR: the influence of some non-bonded interactions on 3JCC Four types of non-bonded interactions that could influence vicinal carbon-carbon NMR coupling constants… more
Date: May 1982
Creator: Canada, Edward D. (Edward Dee)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis and reactions of poly(ethynyldialkylsilanes)

Description: A nucleophilic cleavage reaction of 2,2,5,5,8,8-hexamethyl-2,5,8-trisilanona-3,6-diyne, I, with several bases, occurs rapidly at room temperature in both polar and non-polar solvents. An attack occurs exclusively at the central silicon regardless of the steric requirements of the bases (alkyllithium). The major products from the reaction of I with tert-butyllithium followed by hydrolysis were 2,2,5,5,6,6-hexamethyl-2,5-disilahepta-3-yne, II, and 2,2,5,5-tetramethyl-2,5-disilahexa-3-yne, VI.
Date: December 1990
Creator: Jo, Kyo Dong
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Charts for the Computation of Equilibrium Composition of Chemical Reactions in the Carbon-Hydrogen-Oxygen-Nitrogen System at Temperatures From 2000° to 5000° Degrees K

Description: Charts are provided for the estimation and progressive adjustment of two independent variables on which the calculations are based. Additional charts are provided for the graphical calculation of the composition.
Date: July 1948
Creator: Huff, Vearl N. & Calvert, Clyde S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preparation of N-Polychloropolyfluoroheptane

Description: From introduction: "Discussion of alternate processes for manufacture of perfluoroxylene as insurance against any eventuality, e.g. disaster, poor quality, required amount of elemental fluorine not obtainable, necessity for further expansion at some future date, or decreasing cost."
Date: 1946
Creator: Babcock, J. H.; Beanblossom, W. S. & Wojcik, B. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Mechanism of Formation and Lifetimes of Halogenated Ketenes

Description: The investigation presented here is in two parts: a mechanistic study of the triethylamine dehydrohalogenation of ac-haloacid halides to form halogenated ketenes and a study of steric influence upon ketene lifetimes. The first part of this research deals with the mechanism of the dehydrohalogenation reaction. Two acid halides, isobutyryl chloride and a-chloropropionyl chloride, appeared to represent two mechanistic extremes for this reaction with triethylamine. Isobutyryl chloride reacted with … more
Date: August 1974
Creator: Scherubel, Gary
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Nonlinear Waves in Reaction Diffusion Systems: The Effect of Transport Memory

Description: Motivated by the problem of determining stress distributions in granular materials, we study the effect of finite transport correlation times on the propagation of nonlinear wavefronts in reaction diffusion systems. We obtain new results such as the possibility of spatial oscillations in the wavefront shape for certain values of the system parameters and high enough wavefront speeds. We also generalize earlier known results concerning the minimum wavefront speed and shape-speed relationships st… more
Date: November 4, 1999
Creator: Hurd, Alan J.; Kenkre, v. M. & Manne, K. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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