Digital Commons Network^™

Determination Of Size Distributions In Heterodisperse Systems Of Homogeneous, Non-Absorbing Spheres From Angular Light Scattering Extrema, Werner Bergman

Wayne State University Dissertations

No abstract provided.

Characterization Of Trace Iron Species In Natural Water, James Robert Johnson

Dissertations and Theses

The distribution and speciation of trace metals in natural waters is only slightly, at best, understood. Interactions with organic substances can effectively distribute the metals throughout many ill-defined physical and chemical. To better comprehend the complexity of metal-organic interactions this work focused on the delineation of trace iron species present in a natural system. The separation of Fe(II) and Fe(III) was successfully accomplished using a variation of an ion exchange method involving resin-loaded filter paper. The quantitation of the various iron species was determined using linear scan voltammetry and atomic absorption. The total iron concentration, determined as the sum of …

Comparisons Between Oriented Film And Solution Tertiary Structure Of Various Nucleic Acids, Douglas R. C. Priore

Chemistry and Chemical Biology ETDs

It was desired to help establish whether or not the tertiary structure of a biomolecule is the same in a cry­stal (or an oriented film) as it is in solution. Generally it is accepted that the structures in these diverse environ­ments are similar, if not identical. By comparing the extinction coefficients obtained from oriented film data to those obtained from solution data it was hoped that this question might further be resolved. To this end an electric dichroism instrument built in our lab was used to measure the dichroic signal so as to calculate, with the help of the ultraviolet …

Infrared-To-Visible Upconversion In Rare Earth Doped Materials, Deon G. Ettinger

Chemistry and Chemical Biology ETDs

Upconversion materials have been prepared which may be stimulated by incident 970 nm radiation to emit in the visible region. The couples Yb⁺³-Ho⁺³ in a YF₃ host and Yb⁺³-Er⁺³ in YF₃, YPO₄, Li₃PO₄ and Y₂O₂S hosts have been studied at temperatures from 9K to 273K. For (Y_.80Yb_.19Er_.01)F₃ emission bands at 657 nm, 538 nm, 520 nm, 409 nm and 379 nm have been detected and determined to result from 3-, 2-, 2-, 3-, and 3-photon …

Conversion Of Farnesyl Pyrophosphate And Squalene To Sterols By Rat Liver Microsomal Enzymes: Specificity Of Sterol Carrier Protein₁, Kathleen Lobaugh Gavey

Chemistry and Chemical Biology ETDs

The conversion of farnesyl pyrophosphate to squalene by rat liver microsomes was investigated. The enzyme exhibited an apparent maximum velocity at a substrate concentration of 30 μM. No evidence of substrate inhibition was seen at concentrations up to 65 μM. Phosphatases present in the microsomes or in the 105,000 x g supernatant (S105) did not interfere with squalene synthesis under the experimental conditions used.

s₁₀₅ slightly enhanced the biosynthesis of squalene at the lowest concentrations of microsomal protein studied. The effect was reversed at higher concentrations of microsomes. A 1O-fold increase in the concentration of s₁₀₅ did not …

Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott L. Whittenburg, C. H. Wang

Chemistry and Biochemistry Faculty Publications

The zero‐frequency shear wave dip appearing in the depolarized Rayleigh spectrum in benzonitrile has been studied as a function of concentration and temperature. The solution study was carried out at constant viscosity equal to the viscosity of liquid benzonitrile at each temperature. The result indicates that the presence of shear wave fine structure does not depend on the collective orientational fluctuations. The orientational and vibrational relaxation times of benzonitrile were measured at various concentrations and temperatures. The orientational relaxation times show no concentration dependence at any temperature, suggesting that the pair correlation is negligible at all concentrations. The orientational relaxation …

Light Scattering Studies Of Transverse Sound Wave And Molecular Motion In Benzonitrile, Scott Whittenburg

Chemistry Faculty Publications

The zero-frequency shear wave dip appearing in the depolarized Rayleigh spectrum in benzonitrile has been studied as a function of concentration and temperature. The solution study was carried out at constant viscosity equal to the viscosity of liquid benzonitrile at each temperature. The result indicates that the presence of shear wave fine structure does not depend on the collective orientational fluctuations. The orientational and vibrational relaxation times of benzonitrile were measured at various concentrations and temperatures. The orientational relaxation times show no concentration dependence at any temperature, suggesting that the pair correlation is negligible at all concentrations. The orientational relaxation …

Metal-Ion Oxidative Decarboxylations. 9. Reaction Of Benzilic Acid With Cerium(Iv) In Acidic Perchlorate And Sulfate Media, Samir B. Hanna, Sezai A. Sarac

Chemistry Faculty Research & Creative Works

The kinetics of oxidation of benzylic acid (HLH) to benzophenone by cerium (IV) has been studied in several media using the stopped-flow technique. In HClO₄-Na₂SO₄-NaClO₄ media, which allow for the variation and control of the concentrations of the various Ce(IV) species at constant [H⁺] and ionic strength, the rate data suggest CeSO₄²⁺ as the kinetically relevant species. In HClO₄ the observed first-order rate constants, tetrad, first increase with increasing HLH concentration, then decrease slightly at higher substrate concentrations suggesting the intermediacy of two complexes: a reactive [Ce(IV)HL] and …

Micellar Solutions Versus Microemulsions, Derek G. Rance, Stig Friberg

Chemistry Faculty Research & Creative Works

No abstract provided.

Metal-Ion Oxidative Decarboxylations. 10. Substituent Effects In The Cerium(Iv)-Benzilic Acids Reaction, Samir B. Hanna, Sezai A. Sarac

Chemistry Faculty Research & Creative Works

The rates of oxidation by cerium (IV) of several substituted benzylic acids (unsubstituted, 2,2′-dichloro, 4,4′-dichloro, 4,4′-dimethyl, 4,4′-dimethoxy, and 4,4′-dinitro) to the corresponding benzophenones have been studied spectrophotometrically in aqueous H₂SO₄, aqueous HClO₄-HOAc, and acetonitrile. The rates are much slower in H₂SO₄ than in the other two media, probably because of heavy sulfato complexation of cerium(IV). The px as of the various acids were determined potentiometrically. The Hammett p values in acetonitrile and HClO₄-HOAc media, derived from correlations with several sets of σ constants and with the newly determined pK …

Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott L. Whittenburg, C. H. Wang

Chemistry and Biochemistry Faculty Publications

The rotational and vibrational relaxation times of acetonitrile–carbon tetrachloride solutions were investigated as a function of concentration, viscosity, and temperature using depolarized Rayleigh and Raman scattering. Using a Fabry‐Perot interferometer and single frequency laser source, we have shown that reliable results for the single particle orientational correlation times (τ_s) for CH₃CN can be obtained by carrying out a concentration dependent depolarized Rayleigh scattering study. Raman scattering was shown to yield inconsistent results for τ_s in CH₃CN. At constant viscosity, it was found that the Rayleigh scatteringrelaxation time (τ_Ray) of CH_{3 …}

Charge Transfer Photochemistry Of Some Chromium (Iii) Complexes, Yohn Sik Kang

Chemistry and Chemical Biology ETDs

The photolyses of a series of chromium(III) complexes Cr(en)3 3+, Cr(den)2 3+, Cr(tn)3 3+, and Cr(pn)3 3+, where en= ethylenediamine, den= diethylenetriamine, tn = trimethylenediamine, and pn = propylenediamine, have been investigated. Experiments were carried out on unbuffered and buffered (pH= 2.00) solutions containing 10^-3 – 10^-2 M chromium(III) complexes at room temperature and 10°C. While purging with argon or oxygen, the irradiation was performed with 184.9-253.7 nm u.v. light, corresponding to the charge transfer bands of the complex.

Photochemistry Of Alpha, Beta-Unsaturated Nitro Compounds, Charles Elmore

Masters Theses & Specialist Projects

A total of twelve α ,β - unsaturated nitro compounds of the form

Ar-C=C-NO₂

| |

H R

(where Ar=phenyl, o-methylphenyl, mesityl, α - naphthyl, and β - naphthyl; R=hydrogen, methyl, ethyl, and phenyl) were prepared and irradiated with ultraviolet light. When the corresponding α - oximinoketone was formed, it was recovered and identified. Six of the α , β - unsaturated nitro compounds and one α - oximinoketone had not been previously reported. Yields of irradiation products were determined and a kinetic study performed on these.

The effect of substituents size at the β - position of α …

Computer Simulation Of The Rotational Spectrum Of A Symmetric Top Molecule, W. Scott Wells

Masters Theses & Specialist Projects

Given the proper equations and the appropriate set of selection rules, a computer can be programmed to simulate the spectrum of a molecule. This study deals with the rotational spectrum of a symmetric top molecule. The program itself was written in several subroutine blocks. By doing this the computing time was reduced by 70% over similar programs.

The program can be used to simulate the spectrum of a molecule if the transition polarization type and the rotational constants are known. However, if the type of transition polarization or constants is unknown, the program can be used as a tool for …

Light Scattering Studies Of Rotational And Vibrational Relaxations Of Acetonitrile In Carbon Tetrachloride, Scott Whittenburg

Chemistry Faculty Publications

The rotational and vibrational relaxation times of acetonitrile-carbon tetrachloride solutions were investigated as a function of concentration. viscosity, and temperature using depolarized Rayleigh and Raman scattering. Using a Fabry-Perot interferometer and single frequency laser source, we have shown that reliable results for the single particle orientational correlation times (T,) for -CH3CN can be obtained by carrying out a concentration dependent depolarized Rayleigh scattering study. Raman scattering was shown to yield inconsistent results for T. in CH3CN. At constant viscosity, it was found that the Rayleigh scattering relaxation time (TRay) of CH3CN in CCI. does not change with CH3CN concentration, indicating …

Chromium(Iii) Tartrates, Gerald Lynn Robbins

Chemistry and Chemical Biology ETDs

The binuclear tartrate-bridged complexes [Cr₂ (tartH)₂ (L)₂] and Na[Cr₂ (tart) (tartH) (L)₂]("tart" = C₄H₂O₆^4-, "tartH" = C₄H₃O₆^3- and "L"= 1,10-phenanthroline or 2,2'-bipyridyl) have been synthesized where each complex contains either two optically active or two meso bridging ligands. A discussion of the number of isomers and symmetries of these complexes is presented, as well as a complete description of the syntheses of the complexes and their sodium salts. Steric constraints force the octahedral coordination geometry for the dimer containing two …

Kinetics And Mechanism Of The Solvolysis Of The Cis- And Trans-5, 5-Dimethyl-1, 3-Cyclohexanediol Bis-P-Toluenesulfonate In Aqueous Pyridine, Louis Frederick Holzknecht

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Sciences and Mathematics School at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Chemistry by Louis Frederick Holzknecht on April 5, 1977.

A Comparison Of Various Pattern Recognition Techniques, Larry Wood

Masters Theses & Specialist Projects

A comparison of the reliability of three pattern recognition classifiers has been made using data having a great amount of variation. The basic concepts of the Linear Learning Machine, the K Nearest Neighbor Classifier, and the Potential Function Classifier are presented. Prediction of whether a student would pass or fail freshmen Chemistry 120 was made, based on various test results. The Linear Learning Machine was found to be an unworkable classifier for this kind of data. Both the Potential Function Classifier and the K Nearest Neighbor classifier were acceptable with the Potential Function Classifier being generally a better classifier.

The Synthesis And Physical Properties Of Some 1-Methyl And 2-Methyl Bridged Cycloheptapyrazolones, Gary R. Larson

Masters Theses

No abstract provided.

The Dependence Of The Apparent Pk Of Ion Exchange Celluloses Of Ionic Strength, Paul Cyril Gillespie

Theses and Dissertations

Diethylaminoethyl cellulose was titrated with acid and base in various concentrations of NaCl. The pK values were determined from titration curves using a graphical technique. Two titratable groups were observed from the acid titration curve, a major and a minor group. The minor group, which represented 20% of the acid titration, was barely detectable in the base titration curve and had a salt-independent pK of 6.0. The pK of the major group was strongly salt-dependent and was approximately a linear function of log N NaCl. An equilibrium shift caused by the counter ion may explain the salt dependence. Hydrogen bonding …

Side-Chain Metalations Of Certain Dimethylpyridines By Means Of Organoalkali Metal Reagents, Stephen Bendzunas

Masters Theses

No abstract provided.

Studies Toward The Total Synthesis Of A Colchicine Analog, Jacob Shya Tou

Masters Theses

No abstract provided.

Unusual Alkylations Of The 1,1-Diphenyl-2-Propanone Dianion, Ruth E. Tenbrink

Masters Theses

No abstract provided.

The Synthesis And Study Of The Enolate Monoanion Of 2, 4-Di-P-Anisylbicyclo(3.2.1)Oct-6-En-3-One, Phillip D. Reynhout

Masters Theses

No abstract provided.

Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Angle dependent intermolecular potential energy surfaces for the two states (2A’ and 2A”) that arise from the interaction of ground (X^2II) state NO with Ar are calculated using the electron gas model to obtain the short range interactions. The average and difference of the two interaction energies are fit to analytic forms convenient for use in scattering calculations and joined smoothly onto the long range van der Waals potential previously determined. The results, which appear to be of useful accuracy, and the applicability of the electron gas model to such open shell–closed shell interactions are discussed.

Conformational Analysis Of 1-Tertiarybutyl-1, 4-Dihydronaphthalene A Turnover From Srni To Sni Mechanism, Su-Jen Huang

Masters Theses & Specialist Projects

The cyclohexadiene porition of 1-tertiarybutyl-1, 4-dihydronaphthalene exists in a puckered rather than planar conformation at room temperature, with approximately equal populations of the isomer with the t-butyl group “axial” and “equatorial.” Analysis of chemical shifts and coupling constants was aided by use of a LAOCOON III program.

Excited States And Photochemistry Of Saturated Molecules, Patrick M. Saatzer, Robert D. Koob, Mark S. Gordon

Office of the Provost Scholarship

The molecular structures and bond energies in the low-lying excited states of n-alkanes from methane to n-pentane are investigated using the semi-empirical INDO method with configuration interaction. In general the calculated geometries and bond energies are consistent with the known threshold photochemistry of these molecules, the only exception being the prediction of vicinal (rather than geminal) elimination of H₂ in ethane. It appears that INDO overestimates the amount of angular distortion in these excited states.

Methylation Of The Metal Salts Of 2- And 4-Pyridine Diazotates, Chirasarit Thamavit

University of the Pacific Theses and Dissertations

No abstract provided.

Reactions Of 1-Bromo-2-(P-Tolyl)Cyclopropane With Nucleophiles In The Presence Of Crown Ether, Gerald Mccomas

Masters Theses

Reactions of 1-bromo-2-(p-tolyl)cyclopropane with potassium acetate in the presence of crown ether in various solvents (DMSO, t-butanol, and toluene) have been examined. No cyclopropyl products were observed, only ring-opened p-methylsinnamyl acetates. The trans 1-bromo-2-(p-tolyl)cyclopropane isomer reacts about 3.8 times faster than the cis isomer in DMSO, but only about 1.5 times faster in t-butanol, seemingly related to solvation factors in the transition state. Although stability studies indicated that p-methylcinnamyl bromide might be an intermediate, the rate of formation of this compound in the absence of potassium acetate was much lower than rate of product formation even in the presence of …

The Preparation Of Coordination Compounds Of Rhodium (Iii) With Cycloalkanecarboxylic Acid, Robert Adrian Alameda

University of the Pacific Theses and Dissertations

The purpose of this study was to prepare and characterize the coordination compounds produced by the reaction of five cycloalkanecarboxylic acids and a rhodium salt. The five acids that furnished the ligands were: cyclopropanecarboxylic acid, cyclobutanecrboxylic acid, cyclopentanecarboxylit acid, cyclohexanecarboxylic acid, and a cycloheptanecarboxylic acid. The rhodium (Ill) ion was provided by the salt Na₃RhCl₆•12H₂0, A survey of the available literature indicated that these rhodium (Ill) cyclo-alkane carboxylates had not previously been prepared.