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Thermodynamic Properties of Nonelectrolyte Solutes in Ternary Solvent Mixtures

Description: The purpose of this dissertation is to investigate the thermodynamic properties of nonelectrolyte solutes dissolved in ternary solvent mixtures, and to develop mathematical expressions for predicting and describing that behavior in the solvent mixtures. Thirty-four ternary solvent systems were studied containing either alcohol (1-propanol, 2-propanol, 1-butanol, and 2-butanol), alkane (cyclohexane, heptane, and 2,2,4-trimethylpentane) or alkoxyalcohol (2-ethoxyethanol and 2-butoxyethanol) cosol… more
Date: August 1999
Creator: Deng, Tʻai-ho
Partner: UNT Libraries
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Experimental and Theoretical Studies of Polycarbocyclic Compounds

Description: Part I. Diels-Alder cycloadditions of 1,2,3,4,9,9-hexachloro-1α,4α,4aα,8aβ-tetrahydro-l,4-methanonaphthalene (32) and 1,2,3,4,9,9-hexachloro-lα,4α,6,7- tetrahydro-l,4-methanonaphthalene (33) to 4-methyl- and 4-phenyl-l,2,4-triazoline-3,5-dione [MTAD and PTAD, respectively] and to N-methylmaleimide (NMM) have been studied. The structures of several of the resulting cycloadducts were determined by X-ray crystallographic methods. The observed stereoselectivity of each of these Diels-Alder reaction… more
Date: May 1998
Creator: Shukla, Rajesh, 1964-
Partner: UNT Libraries
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The Development of Predictive Models for the Acid Degradation of Chrysotile Asbestos

Description: The purpose of this study was to determine the factors affecting the acid degradation of chrysotile asbestos (Mg_3Si_2O_5(OH_4)) . Millions of tons of asbestos have found use in this country as insulative or ablative material. More than 95 percent of the asbestos in use is of the chrysotile variety. The remaining 5 percent is composed of various types of fibrous amphiboles. The inhalation of asbestos can lead to several diseases in humans. Asbestosis, lung cancer and mesothelioma are the most c… more
Date: May 1993
Creator: Ingram, Kevin D. (Kevin Dean)
Partner: UNT Libraries
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Spectrofluorometric and Solubility Studies of Polycyclic Aromatic Hydrocarbons in Hydrogen Bonded Binary Solvent Mixtures

Description: The purpose of this dissertation is to investigate the behavior of polycyclic aromatic hydrocarbons (PAHs) in binary solvent systems and determine and/or develop predictive mathematical expressions for describing solutions in which hydrogen-bonding occurs.
Date: May 1997
Creator: Powell, Joyce R., 1968-
Partner: UNT Libraries

Layered Double Hydroxides and the Origins of Life on Earth

Description: A brief introduction to the current state of research in the Origins of Life field is given in Part I of this work. Part II covers original research performed by the author and co-workers. Layered Double Hydroxide (LDH) systems are anion-exchanging clays that have the general formula M(II)xM(III)(OH)(2x+2)Y, where M(II) and M(III) are any divalent and trivalent metals, respectively. Y can be nearly any anion, although modern naturally occuring LDH systems incorporate carbonate (CO32-), chloride… more
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Date: May 2001
Creator: Brister, Brian
Partner: UNT Libraries
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High-Temperature Corrosion of Aluminum Alloys: Oxide-Alloy Interactions and Sulfur Interface Chemistry

Description: The spallation of aluminum, chromium, and iron oxide scales is a chronic problem that critically impacts technological applications like aerospace, power plant operation, catalysis, petrochemical industry, and the fabrication of composite materials. The presence of interfacial impurities, mainly sulfur, has been reported to accelerate spallation, thereby promoting the high-temperature corrosion of metals and alloys. The precise mechanism for sulfur-induced destruction of oxides, however, is amb… more
Date: December 2000
Creator: Addepalli, Swarnagowri
Partner: UNT Libraries
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Epoxy + Liquid Crystalline Epoxy Coreacted Networks

Description: Molecular reinforcement through in-situ polymerization of liquid crystalline epoxies (LCEs) and a non-liquid crystalline epoxy has been investigated. Three LCEs: diglycidyl ether of 4,4'-dihydroxybiphenol (DGE-DHBP) and digylcidyl ether of 4-hydroxyphenyl-4"-hydroxybiphenyl-4'-carboxylate (DGE-HHC), were synthesized and blended with diglycidyl ether of bisphenol F (DGEBP-F) and subsequently cured with anhydride and amine curing agents. Curing kinetics were determined using differential scanning… more
Date: December 2000
Creator: Punchaipetch, Prakaipetch
Partner: UNT Libraries
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Supplemental Material: Enthalpy of Solvation Correlations for Gaseous Solutes Dissolved in Alcohol Solvents Based on the Abraham Model

Description: This document includes supplemental material to an article titled "Enthalpy of solvation correlations for gaseous solutes dissolved in alcohol solvents based on the Abraham model," published in QSAR & Combinatorial Science.
Date: December 7, 2007
Creator: Mintz, Christina; Ladlie, Tara; Burton, Katherine; Clark, Michael; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences
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Supplemental Material for Correlation of Human and Animal Air-to-Blood Partition Coefficients with a Single Linear Free Energy Relationship Model

Description: This document includes supplemental material to an article titled "Correlation of human and animal air-to-blood partition coefficients with a single linear free energy relationship model," published in QSAR & Combinatorial Science.
Date: July 25, 2008
Creator: Sprunger, Laura M.; Gibbs, Jennifer; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Comments Regarding "Density, Speed of Sound, Refractive Index and Derivatives Properties of the Binary Mixture N-Hexane + N-Heptane (or N-Octane or N-Nonane), T = 288.15 - 313.15 K"

Description: This article offers comment on "Density, speed of sound, refractive index and derivatives properties of the binary mixture N-Hexane + N-Heptane (or N-Octane or N-Nonane), T=288.15 - 313.15 K."
Date: April 9, 2013
Creator: Acree, William E. (William Eugene) & Stephens, Timothy W.
Partner: UNT College of Arts and Sciences
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Thermochemical investigations of crystalline solutes in non-electrolyte solutions: Mathematical representation of solubility data and the development of predictive solubility equations in systems with specific and non-specific interactions.

Description: Understanding the thermodynamic properties of multicomponent mixtures is of critical importance in many chemical and industrial applications. Experimental measurements become progressively difficult as the number of solution components increases -- producing the need for predictive models. Problems in development of predictive models arise if the mixture has one or more components that interact through molecular complexation or association. Experimental solubilities of anthracene and pyrene di… more
Date: May 2008
Creator: Zvaigzne, Anita Ilze
Partner: UNT Libraries
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Predicting Chemical and Biochemical Properties Using the Abraham General Solvation Model

Description: Several studies were done to illustrate the versatillity of the Abraham model in mathematically describing the various solute-solvent interactions found in a wide range of different chemical and biological systems. The first study focused on using the solvation model to construct mathematical correlations describing the minimum inhibitory concentration of organic compounds for growth inhibition towards the three bacterial strains Porphyromonas gingivalis, Selenomonas artemidis, and Streptococc… more
Date: May 2009
Creator: Mintz, Christina
Partner: UNT Libraries
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Substitution Chemistry of the Cobalt Complexes [Co₂(CO)₆(PhC≡CR) (R=Ph, H) and PhCCo₃(CO)₉] with the Diphosphine Ligands [Bis(diphenylphosphino)maleic Anhydride (BMA) and (Z)-Ph₂PCH=CHPPh₂]. Reversible Chelate-to-Bridge Diphosphine Ligand Exchange, Phosphorus-Carbon Bond Cleavage and Phosphorus-Carbon Bond Formation

Description: The tricobalt cluster PhCCo3(CO)9 (1) reacts with the bidentate phosphine ligand 2,3-bis(diphenylphosphino)maleic anhydride (bma) in the presence of added Me3NO to give the diphosphine-substituted cluster PhCCo3(CO)7(bma) (2). Cluster 2 is unstable in solution, readily losing CO to afford Co3(CO)6[(μ2-η2/η1-C(Ph)C=C(PPh2)C(O)OC(O)](μ2-PPh2) (3) as the sole observed product. VT-31P NMR measurements on cluster 2 indicate that the bma ligand functions as both a chelating and a bridging ligand. At … more
Date: December 1994
Creator: Yang, Kaiyuan
Partner: UNT Libraries
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The preparation and characterization of thermo-sensitive colored hydrogel film and surfactant-free porous polystyrene three-dimensional network.

Description: Polymer hydrogel films change their properties in response to environmental change. This remarkable phenomenon results in many potential applications of polymer hydrogel films. In this thesis colored thermo-sensitive poly(N-isopropylacrylamide) (PNIPAAm) hydrogel film was prepared by firstly synthesizing polymer latex and secondarily crosslinking the nanoparticles and casting the polymers onto glass. The shape-memory effect has been observed when changing the environmental temperature. The temp… more
Date: December 2001
Creator: Zhou, Bo
Partner: UNT Libraries
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Supporting Material for: Thermochemical Investigations of Solute Transfer into Ionic Liquid Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions

Description: This document includes supplemental material to an article titled "Thermochemical Investigations of Solute Transfer into Ionic Liquid Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions," published in Physics and Chemistry of Liquids.
Date: February 25, 2014
Creator: Stephens, Timothy W.; Chou, Vicky; Quay, Amanda N.; Shen, Connie; Dabadge, Nishu; Tian, Amy et al.
Partner: UNT College of Arts and Sciences
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Comments Concerning "Study of Molecular Interaction in Binary Liquid Mixtures of Ethyl Acetoacetate with Chloroform and Dimethylsulphoxide using Excess Acoustic Parameters and Spectroscopic Methods

Description: Article commenting on a previously published article, "Study of molecular interaction in binary liquid mixtures of ethyl acetoacetate with chloroform and dimethylsulphoxide using excess acoustic parameters and spectroscopic methods."
Date: February 18, 2014
Creator: Acree, William E. (William Eugene) & Stephens, Timothy W.
Partner: UNT College of Arts and Sciences
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Thermochemical Investigations of Solute Transfer into Ionic Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions

Description: Article on thermochemical investigations of solute transfer into ionic liquid solvents and updated Abraham model equation coefficients for solute activity coefficient and partition coefficient predictions.
Date: February 25, 2014
Creator: Stephens, Timothy W.; Chou, Vicky; Quay, Amanda N.; Shen, Connie; Dabadge, Nishu; Tian, Amy et al.
Partner: UNT College of Arts and Sciences
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Combined Electrochemistry and Spectroscopy of Complexes and Supramolecules containing Bipyridyl and Other Azabiphenyl Building Blocks

Description: A group of azabiphenyl complexes and supramolecules, and their reduced and oxidized forms when possible, were characterized by cyclic voltammetry and electronic absorption spectroscopy. The oxidized and reduced species, if sufficiently stable, were further generated electrochemically inside a specially designed quartz cell with optically transparent electrode, so that the spectra of the electrochemically generated species could be taken in situ. Assignments were proposed for both parent and pro… more
Date: August 1995
Creator: Yang, Lei
Partner: UNT Libraries
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Thermochemical Investigation of Ternary Nonelectrolyte Mixtures

Description: Excess molar volumes have been determined for four ternary chlorobenzene + dibutyl ether + alkane mixtures at 25°C. Results of these measurements are used to test the applications and limitations of BAB, Redlich-Kister, Kohler and Hwang et al. cubic models. For the systems studied, Redlich- Kister, Kohler and Cubic models were found to provide reasonable predictions. Differences between experimental and predicted ΔV^ex_123 values were about ±0.020 cm^3mol^-1 or less at most ternary compositions… more
Date: December 1992
Creator: Teng, I-Lih
Partner: UNT Libraries
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Ab Initio and Density Functional Investigation of the Conformer Manifold of Melatonin and a Proposal for a Simple Dft-based Diagnostic for Nondynamical Correlation

Description: In this work we address two problems in computational chemistry relevant to biomolecular modeling. In the first project, we consider the conformer space of melatonin as a a representative example of “real-life” flexible biomolecules. Geometries for all 52 unique conformers are optimized using spin-component scaled MP2, and then relative energies are obtained at the CCSD (T) level near the complete basis set limit. These are then used to validate a variety of DFT methods with and without empiric… more
Date: August 2013
Creator: Fogueri, Uma
Partner: UNT Libraries
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Solderability Study of Tin/Lead Alloy Under Steam-Aging Treatment by Electrochemical Reduction Analysis and Wetting Balance Tests

Description: Two types of solder samples, pins and through-holes were tested by SERA™ (Sequential Electrochemical Reduction Analysis) and Wetting Balance after various length of steamaging treatment. It was shown that after steam-aging, both types of specimen gave a similar electrochemical reduction curve, and solderabilty predictions made from SERA™ test agree with results obtained from Wetting Balance test on a qualitative base. Wetting balance test of pin samples after SERA™ test confirmed that SERA™ is … more
Date: May 1993
Creator: Gao, Yang, 1966-
Partner: UNT Libraries
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ab initio Solubility Prediction of Non-Electrolytes in Ternary Solvents Using a Combination of Jouyban-Acree and Abraham Models

Description: Article on the ab initio solubility prediction of non-electrolytes in ternary solvents using a combination of Jouyban-Acree and Abraham models.
Date: May 1, 2008
Creator: Jouyban, Abolghasem; Khoubnasabjafari, Maryam; Hamidi, Ali A. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences
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