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in creator/contributor: "Acree, William E. William Eugene"  
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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
Item Type: Refine your search to only Thesis or Dissertation
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-
Item Type: Refine your search to only Thesis or Dissertation
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)
Item Type: Refine your search to only Thesis or Dissertation
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-
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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.)
Item Type: Refine your search to only Text
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.)
Item Type: Refine your search to only Text
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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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.
Item Type: Refine your search to only Text
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.
Item Type: Refine your search to only Article
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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Free Radical Induced Oxidation, Reduction and Metallization of NiSi and Ni(Pt)Si Surfaces

Description: NiSi and Ni(Pt)Si, and of the effects of dissociated ammonia on oxide reduction was carried out under controlled ultrahigh vacuum (UHV) conditions. X-ray photoelectron spectroscopy (XPS) has been used to characterize the evolution of surface composition. Vicinal surfaces on NiSi and Ni(Pt)Si were formed in UHV by a combination of Ar+ sputtering and thermal annealing. Oxidation of these surfaces in the presence of either O+O2 or pure O2 at room temperature results in the initial formation of a S… more
Date: August 2010
Creator: Manandhar, Sudha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Affordances of Instrumentation in General Chemistry Laboratories

Description: The purpose of this study is to find out what students in the first chemistry course at the undergraduate level (general chemistry for science majors) know about the affordances of instrumentation used in the general chemistry laboratory and how their knowledge develops over time. Overall, students see the PASCO™ system as a useful and accurate measuring tool for general chemistry labs. They see the probeware as easy to use, portable, and able to interact with computers. Students find that the … more
Date: August 2010
Creator: Sherman, Kristin Mary Daniels
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Examining and Characterizing Changes in First Year High School Chemistry Curricula

Description: Many students currently entering college are able to solve mathematical problems but often do not understand the chemistry concepts underlying their calculations. High school chemistry teachers from Texas and the United States (US) were surveyed as to what topics they teach in their chemistry classes. A subset of Texas teachers was also interviewed about their instruction. The survey indicated that less-experienced Texas teachers are omitting a number of topics from their chemistry instruction,… more
Date: August 2010
Creator: Holley, Kerry Kathleen McGee
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Supporting Information: Thermochemical studies on 3-methylquinoxaline-2-carboxamide 1,4-dioxide derivatives: enthalpies of formation and of (N-O) bond dissociation

Description: This document includes supplemental material to an article titled "Thermochemical studies on 3-methylquinoxaline-2-carboxamide 1,4-dioxide derivatives: enthalpies of formation and of (N-O) bond dissociation," published in the Journal of Physical Chemistry B.
Date: February 3, 2007
Creator: Gomes, José R. B.; Sousa, Emanuel A.; Gomes, Paula; Vale, Nuno; Gonçalves, Jorge M.; Pandey, Siddharth et al.
Item Type: Refine your search to only Text
Partner: UNT College of Arts and Sciences
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