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Thermodynamic Properties of Organic Compounds. 2. Combustion and Sublimation Enthalpies of 2,4,6-Trimethylbenzonitrile N-Oxide

Description: Article discussing thermodynamic properties of organic compounds and combustion and sublimation enthalpies of 2,4,6-trimethylbenzonitrile N-oxide.
Date: January 1992
Creator: Acree, William E. (William Eugene); Simirsky, Vladimir V.; Kozyro, Alexander A.; Krasulin, Alexander P.; Kabo, Gennady J. & Frenkel, Michael L.
Partner: UNT College of Arts and Sciences

Supporting Material for: Enthalpy of Solvation Correlations for Gaseous Solutes Dissolved in Water and in 1-Octanol Based on the Abraham Model

Description: This document includes supporting material for an article titled, "Enthalpy of solvation correlations for gaseous solutes dissolved in water and in 1-octanol based on the Abraham model," published in the Journal of Chemical Information and Modeling.
Date: December 15, 2007
Creator: Mintz, Christina; Clark, Michael; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Partition Coefficients of Organic Compounds in New Imidazolium and Tetralkylammonium Based Ionic Liquids Using Inverse Gas Chromatography

Description: This article discusses partition coefficients of organic compounds in new imidazolium and tetralkylammonium based ionic liquids using inverse gas chromatography.
Date: September 11, 2009
Creator: Mutelet, Fabrice; Revelli, Anne-Laure; Jaubert, Jean-Noël; Sprunger, Laura M.; Baker, Gary A. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Thermodynamic Properties of Organic Compounds. 3. Sublimation Enthalpy and Heat Capacities of 2,4,6-Trimethylbenzonitrile N-oxide

Description: Article discussing thermodynamic properties of organic compounds and sublimation enthalpy and heat capacities of 2,4,6-trimethylbenzonitrile N-oxide.
Date: January 1993
Creator: Acree, William E. (William Eugene); Sevruk, Viktor M.; Kozyro, Alexander A.; Krasulin, Alexander P.; Kabo, Gennady J. & Frenkel, Michael L.
Partner: UNT College of Arts and Sciences

A General Treatment of Solubility. 1. The QSPR Correlation of Solvation Free Energies of Single Solutes in Series of Solvents

Description: Article on a general treatment of solubility and the quantitative structure-property relationship (QSPR) correlation of solvation free energies of single solutes in series of solvents.
Date: October 2, 2003
Creator: Katritzky, Alan R.; Oliferenko, Alexander A.; Oliferenko, Polina V.; Petrukhin, Ruslan; Tatham, Douglas B.; Maran, Uko, 1966- et al.
Partner: UNT College of Arts and Sciences

Silenes and Silenoids in the Chemistry of Cyclopentadienylsilanes

Description: Evidence is presented that apparent silene products obtained from the metalation of cyclopentadienyldimethyl - chlorosilane either with tert-butyl1ithium or with methylenetriphenylphosphorane actually arise from the metalated starting material, a silenoid, rather than from a silafulvene intermediate. Trimethylmethoxysi1ane is shown to be an effective trap for dimethylsilafulvene. A new dimethylsilafulvene precursor, bis(dimethylmethoxysi1yl) cyclopentadiene, which gives high yields of dimethyldimethoxysi1ane and the silafulvene at temperatures as low as 240°C is reported.
Date: August 1986
Creator: Rozell, James M. (James Morris)
Partner: UNT Libraries

Partition Coefficients of Organic Compounds in Four New Tetraalkylammonium Bis(trifluoromethylsulfonyl)imide Ionic Liquids Using Inverse Gas Chromatography

Description: This article discusses partition coefficients of organic compounds in four new tetraalkylammonium bis(trifluoromethylsulfonyl)imide ionic liquids using inverse gas chromatography.
Date: August 18, 2011
Creator: Acree, William E. (William Eugene); Baker, Gary A.; Mutelet, Fabrice & Moïse, Jean-Charles
Partner: UNT College of Arts and Sciences

Syntheses of a New C₂₂H₂₈ Cage Hydrocarbon System and 2,2- Tetramethylene-1 /4-Dibromobutane

Description: (1). An improved method for synthesizing bicyclo (2,2,1) hepta-2,5-diene-7-spiro-1'-cyclopentane (5) has been developed. Thermal reaction of compound (5) with neat iron pentacarbonyl under nitrogen atmosphere affords the corresponding cage dimer (6). Some aspects of the syntheses, spectra, and chemistry of compound (5) and (6) are discussed. (2). A structure isomer of decamethyldodecahedrane (C₃₀H₄₀), molecule (11), is expected to be synthesized via thermal reaction of iron carbonyl complexes with compound (10). An intermediate in this synthesis, 2,2- tetramethylene-1,4-dibromobutane (9) was efficiently synthesized starting from cyclopentanone. Some aspects of the syntheses, spectra, and chemistry of compound (1) to (9) will be discussed.
Date: December 1984
Creator: Wu, An-hsiang
Partner: UNT Libraries

Activity Coefficients at Infinite Dilution of Organic Compounds in Trihexyl(tetradecyl)phosphonium Bis(trifluoromethylsulfonyl)imide Using Inverse Gas Chromatography

Description: Article on activity coefficients at infinite dilution of organic compounds in trihexyl(tetradecyl)phosphonium Bis(trifluoromethylsulfonyl)imide using inverse gas chromatography.
Date: February 2, 2009
Creator: Revelli, Anne-Laure; Sprunger, Laura M.; Gibbs, Jennifer; Acree, William E. (William Eugene); Baker, Gary A. & Mutelet, Fabrice
Partner: UNT College of Arts and Sciences

A group contribution model for determining the sublimation enthalpy of organic compounds at the standard reference temperature of 298 K

Description: Article discussing a group contribution model for determining the sublimation enthalpy of organic compounds at the standard reference temperature of 298 K.
Date: June 21, 2013
Creator: Gharagheizi, Farhad; Ilani-Kashkouli, Poorandokht; Acree, William E. (William Eugene); Mohammadi, Amir H. & Ramjugernath, Deresh
Partner: UNT College of Arts and Sciences

Natural biodegradation of organic contaminants in groundwater

Description: There has recently been a growing awareness that natural processes are degrading contaminants of concern, and that the contribution these natural processes make to achieving cleanup goals needs to be formally considered during site-specific cleanup. Historical case data from a large number of releases has been used to evaluate the expectation for natural attenuation to contribute to the cleanup of petroleum hydrocarbons and chlorinated solvents. The use of historical case data has several advantages, among them: 1) sites can reduce characterization costs by sharing information on key hydrogeologic parameters controlling contaminant fate and transport, and 2) standard reference frameworks can be developed that individual sites can use as a basis of comparison regarding plume behavior. Definition of cleanup times must take into account basic constraints imposed by natural laws governing the transport and natural degradation process of petroleum hydrocarbons. The actual time to reach groundwater cleanup goals is determined by these laws and the limitations on residual subsurface contamination attenuation rates, through either active or natural biological processes. These limitations will practically constrain the time to achieve low concentration cleanup goals. Recognition is needed that sites will need to be transitioned to remediation by natural processes at some point following implementation of active remediation options. The results of an analysis of approximately 1800 California and 600 Texas fuel hydrocarbon (FHC) releases and 2.50 chlorinated volatile organic compound (CVOC) plumes will be summarized. Plume lengths and natural biodegradation potential were evaluated. For FHC releases, 90% of benzene groundwater plumes were less than 280 feet in length and evidence of natural biodegradation was found to be present at all sites studied in detail. For CVOC releases, source strength and groundwater flow velocity are dominant factors controlling groundwater plume lengths. After adjusting for these factors, biodegradation also appears to limit the length of ...
Date: September 23, 1998
Creator: McNab, W W & Rice, D W
Partner: UNT Libraries Government Documents Department

EXTRATERRESTRIAL LIFE: SOME ORGANIC CONSTITUENTS OF METEORITES ANDTHEIR SIGNIFICANCE FOR POSSIBLE EXTRATERRESTRIAL BIOLOGICALEVOLUTION

Description: In order to decide the value and type of information to be obtained from outer space with regard to its pertinence for the evolution of life, a brief review is presented of the current status of our thinking on the origin of life on earth. This points up the particular kinds of chemicals whose presence, or absence, on other astral bodies might be significant. Heretofore, the only data available are the result of telescopic spectroscopy. We report here information indicating the presence in meteorites of complex organic materials, some of them apparently uniquely pertinent to life processes.
Date: December 7, 1959
Creator: Calvin, Melvin & Vaughn, Susan K.
Partner: UNT Libraries Government Documents Department

The Synthesis and Reactivity of Bis(silyl)acetylenes

Description: Six bis(silyl)acetylenes with the following varied silicon substituents were prepared: I (Me, Me); II (H, H); III (Cl, H); IV (Cl, Cl); V (OMe, H); VI (OMe, OMe). While I and II may be prepared by the reaction of dilithio- or bis(bromomagnesium)-acetylide with appropriate chlorosilane, similar reactions designed to give III - VI give oligomers, YMe_2Si(C≡C-SiMe_2)_nY, VII, Y = Cl, OMe, as the major products indicating that the acetylenic functionality on silicon activates the chlorosilane toward nucleophilic substitution. Compounds III and IV were prepared by free radical chlorination of II. Methanolysis of III and IV gave quantitative yields of V and VI, respectively. In the presence of mineral acid, VI readily cyclized to give high yields of the cyclic siloxane octamethyl-4,9-dioxa-3,5,8,10-tetrasila-cyclodeca-1,6-diyne, VIII, and the analogous triyne, IX. It was determined that V and VI could be prepared directly from II in high yield by methanolysis with palladium catalyst. Vaska's complex also accomplished the conversion. I attempted to prepare bis(ethoxydimethylsilyl)acetylene by using of Wilkinson 's catalyst for hydrosilylation with acetaldehyde. The principal product of this reaction was 1-(dimethylsilyl)-3,5,5-trimethyl-4-oxa-3-silacyclopent-1-ene, XI.
Date: May 1987
Creator: Albanesi, Todd E. (Todd Edward)
Partner: UNT Libraries

METHODOLOGY FOR THE NUMBER OF FILTERS NEEDED IN A WASTE BOX

Description: Waste in large waste boxes can generate volatile organic compounds (VOCs) and hydrogen. These waste boxes may or may not have flow paths out of them (although it is believed that most do). These boxes will be retrieved, sampled, and then coated with polyurea. After coating, filters will be installed in the box to keep the concentration of VOCs and hydrogen acceptably low. The MDSA requires that a vent path must be protected during application of the polyurea coating. If the box has been sampled then it is vented and the vent path must be protected. This report provides a model in which the user inputs the free volume of the waste box, sample concentration (ppm of total VOC or volume fraction hydrogen) along with the number of filters to be placed into the waste box lid. Using this information, the model provides an estimate of concentration vs. time or the number of filters needed to reduce the concentration by a specified fraction. If the equations from this report are placed into spreadsheets which are then used to demonstrate TSR compliance, the spreadsheets must come under the Software QA Plan for such documents. Chapters 2 and 3 present the theory. Chapter 4 presents the method with examples of its use found in Chapter 5. Chapter 6 provides the basis far the use of 1,000 ppm as the concentration below which the method is valid under any condition.
Date: May 17, 2007
Creator: MARUSICH, R.M.
Partner: UNT Libraries Government Documents Department