An Abstract Index Theorem on Non-Compact Riemannian Manifolds
Date: 1993
Creator: Anghel, Nicolae
Description: This article discusses an abstract index theorem on non-compact Riemannian manifolds. Abstract: We prove an abstract index theorem for essentially self-adjoint Fredholm supersymmetric first-order elliptic differential operators on Hermitian vector bundles over complete oriented Riemannian manifolds. According to our main result the supersymmetric L2-index of such an operator can be expressed as the sum of a "local contribution" (the familiar Atiyah-Singer index form, suitably restricted to and integrated over a finite region) and a "boundary contribution" (which depends only on the restriction of the operator at large distances). This is done by splicing together local parametrices and Green's operators defined "at infinity". The result yields (in fact is equivalent to) a generalisation of the relative index theorem of Gromov and Lawson.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc159527/
Water Water Everywhere! but not a drop to drink?
Date: April 22, 2013
Creator: Thompson, Ruthanne
Description: This presentation is part of the faculty lecture series UNT Speaks Out on Water Conservation. In this presentation, the author discusses water conservation and sustainability.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157306/
Comments on the Competitive Preferential Solvation Theory
Date: 1990
Creator: Acree, William E. (William Eugene); Zvalgzne, Anita I. & Tucker, Sheryl A.
Description: This article offers comments on the competitive preferential solvation theory. Abstract: Simple additive relationships for the physico-chemical properties of a solute dissolved in binary solvent mixtures are developed from the competitive preferential solvation model. Additive expressions for solute mole fraction solubility and logarithm of solute solubility are mathematically identical to equations derived previously from the microscopic partition and basic nearly ideal binary solvent models. Calculated values based on the various additive relationships are compared to carbazole solubilities in ten binary solvent mixtures containing dibutyl ether with n-hexane, n-heptane, n-octane, cyclohexane, cyclo-octane, methylcyclohexane, iso-octane, n-hexadecane, squalane and t-butylcyclohexane.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157300/
Underwater with a Hand Lens in the Rivers of Cape Horn, Chile; Ecology, Biocultural Conservation and Education at the Top of the World (55°S) or Zen and communicating aquatic ecology at the Top of the World (55°S)
Date: April 22, 2013
Creator: Kennedy, James H.
Description: This presentation is part of the faculty lecture series UNT Speaks Out on Water Conservation. In this presentation, the author discusses the rivers of Cape Horn, Chile and biocultural conservation and education.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157305/
Supporting information for Abraham model correlations for solute partitioning into o-xylene, m-xylene and p-xylene from both water and the gas phase
Date: September 2011
Creator: Stephens, Timothy W.; De la Rosa, Nohelli E.; Saifullah, Mariam; Ye, Shulin; Quay, Amanda; Chou, Vicky et al
Description: This document includes supporting information and figures for an article on the Abraham model correlations for solute partitioning into o-xylene, m-xylene and p-xylene from both water and the gas phase.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157302/
Environmental Imagination River as Bridge
Date: April 22, 2013
Creator: Klaver, Irene
Description: This presentation is part of the faculty lecture series UNT Speaks Out on Water Conservation. In this presentation, the author discusses sustainable resource management and water conservation, including discussions on the Trinity River and water conservation in North Texas.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157288/
Polycyclic Aromatic Hydrocarbon Solute Probes Part II. Effect of Solvent Polarity on the Fluorescence Emission Fine Structures of Coronene Derivatives
Date: February 1989
Creator: Waris, Riaz; Rembert, Michael A.; Acree, William E. (William Eugene); Sellers, David M.; Street, Kenneth W. & Fetzer, John C.
Description: This article discusses the effect of solvent polarity on the fluorescence emission fine structures of coronene derivatives. Abstract: The fluorescence properties of coronene (Co), benzo[a]coronene (BCo), naphtho[2,3-a]coronene (NCo), dibenzo[a,j]coronene (DCo), naphtho[1,2,3,4-ghi]perylene, benzo[pqr]naphtho[8,1,2-bcd]perylene and dibenzo[cd,lm]perylene dissolved in solvents of varying polarity are reported. Measurements indicated that the emission intensities of the four coronene derivatives depended on solvent polarity. The Co, BCo and NCo scales have been defined as the ratio of the fluorescence intensities of bands I and III of the vibronic spectra. Band III of dibenzo[a,j]coronene was not clearly identifiable in all the solvents studied, and the DCo scale was therefore defined as the intensity ratio of band I and IV. Emission intensity ratios of the three perylene derivatives remained nearly constant, irrespective of solvent polarity.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157299/
Analyzing How Business Students Engage in Learning in an Introductory Data Analysis Course
Date: April 12, 2013
Creator: Pavur, Robert J. & Kvanli, Alan H.
Description: This poster discusses an analysis of how business students engage in learning in an introductory data analysis course. A variety of pedagogical activities are used in this introductory data analysis course for business students. In fall of 2012, students were able to score points on each of the following activities: experiential group projects, clicker questions, learning modules, online post chapter quizzes, in class exams, and extra credit questions. An analysis was performed to determine how these activities relate to each other and to improvement in student grades.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157295/
Abraham Model Correlations for Transfer of Neutral Molecules and Ions to Sulfolane
Date: October 15, 2011
Creator: Stephens, Timothy W.; De la Rosa, Nohelli E.; Saifullah, Mariam; Ye, Shulin; Chou, Vicky; Quay, Amanda et al
Description: This article discusses Abraham model correlations for the transfer of neutral molecules and ions to sulfolane. Data have been compiled from the published literature on the partition coefficients of solutes and vapors into anhydrous sulfolane. The logarithms of the water-to-sulfolane partition coefficients, log P, and gas-to-sulfolane partition coefficients, log K, were correlated with the Abraham solvation parameter model. The derived correlations described the observed log P and log K values for solutes dissolved in sulfolane to within average standard deviations of 0.14 log units or less. The log P correlation was extended to include the partition of ions by inclusion of a cation-solvent and an anion-solvent term.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157293/
Enthalpy of Solvation Correlations for Organic Solutes and Gases Dissolved in 2-Propanol, 2-Butanol, 2-Methyl-1-Propanol and Ethanol
Date: August 20, 2011
Creator: Stephens, Timothy W.; De la Rosa, Nohelli E.; Saifullah, Mariam; Ye, Shulin; Chou, Vicky; Quay, Amanda et al
Description: This article discusses the enthalpy of solvation correlations for organic solutes and gases dissolved in 2-propanol, 2-butanol, 2-methyl-1-propanol and ethanol. Abstract: Data have been assembled from the published literature on the enthalpies of solvation for 91 organic vapors and gaseous solutes in 2-propanol, for 73 gaseous compounds in 2-butanol, for 85 gaseous compounds in 2-methyl-1-propanol and for 128 gaseous compounds in ethanol. It is shown that an Abraham solvation equation with five descriptors can be used to correlate the experimental solvation enthalpies to within standard deviations of 2.24 kJ/mole, 1.99 kJ/mole, 1.73 kJ/mole and 2.54 kJ/mole for 2-propanol, 2-butanol, 2-methyl-1-propanol and ethanol, respectively. The derived correlations provide very accurate mathematical descriptions of the measured enthalpy of solvation data at 298 K, which in the case of ethanol span a range of 136 kJ/mole. Division of the experimental values into a training set and a test set shows that there is no bias in predictions, and that the predictive capability of the correlations is better than 3.5 kJ/mole.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc157292/