Digital Commons Network^™

I. A Temperature Dependent Nmr Study Of 6,6-Dicarbethoxy-5,5-Dideuteodi-Benzo--[A,C]-[L, 3]-Cycloheptadiene Ii. The Synthesis Of Four Deuterated Analogs Of 6, 6-Dicarbethoxydibenzo-[A,C]-[1,3]-Cycloheptadiene, Patrick F. Jonas

Masters Theses

The kinetics of conformational interchange of 6,6-dicarbethoxydi-benzo- a,c - 1,3 -cyloheptadiene and its 5,5-dideuterated analog were studied using variable temperature NMR techniques. The free energy of activation for conformational interchange of the parent compound was found to be 9.02 kcal mol^-1 and that of the 5,5-dideuterated analog to be 9.42 kcal mol^-1. Values of the entropy of activation were found to be -19.91 e. u. and -18.12 e. u. respectively. The spectra were recorded on a Nicolet NMC-360 wide bore spectrometer and the data collected treated as an AB spin system.

The 4,8-dideutero, 4,5,5,8-tetradeutero and 5,5,7,7-tetradeutero analogs …

Influence Of Crystal Fields On The Quasimetallic Reflection Spectra Of Crystals: Optical Spectra Of Polymorphs Of A Squarylium Dye, M. Tristani-Kendra, Craig J. Eckhardt

Craig J. Eckhardt Publications

The reflection and Kramers–Kronig absorption spectra have been obtained from the monoclinic and triclinic polymorphs of a squarylium dye, 2,4-bis(4-diethylamino-2-hydroxy phenyl) cyclobutadienediylium-1,3-diolate. The extremely different optical responses were found to arise from two molecular singlet transitions of essentially long axis polarization. Successful application of a four oscillator molecular exciton–polariton theory required the use of point charge densities rather than point dipoles in an extension of the theory which employed both interactions between the two singlets as well as a frequency dependent lattice damping. An intermolecular charge transfer transition is also assigned. The Journal of Chemical Physics is copyrighted by The …

The Nature Of Supported Co-Mo And Ni-W And Hydrodenitrogenation And Hydrodesulfurization Of Model Compounds, Eric Dadey

Masters Theses & Specialist Projects

The catalytic vapor-phase isomerization, hydrogenolysis, and/or disproportionation of trimethylbenzen (TMB) over Co-Mo/Al₂O₃ and Ni-W/Al₂O₃ was studied at 480°C, 400 psi reactor pressure, and a constant H₂ flow. Each catalyst was run in the reduced or sulfided form. The results show a marked difference in the product distributions for each catalyst, which is attributed to differences in the catalysts’ acidities.

The hydrodenitrogenation (HDN) of quinolone and the hydrodesulfurization (HDS) of benzothiophene were also studied. The compounds were reacted in a 1 liter autoclave at 325°C and varying partial pressures of H₂. The …

Determination Of The Internal Rotational Energy Of Gaseous 1,2-Dichloroethane In An Argon Matrix Using Fourier Transform Spectroscopy, Susan Lynn Clarke

Chemistry & Biochemistry Theses & Dissertations

A sample cell and delivery system for rapid matrix isolation of gas mixtures at constant gas temperature was designed and evaluated. The rotational energy differences of 1,2-dichlorosthane and of its deuterium compound wars then determined to test this technique.

The rotational energy barriers calculated from Boltzman plots of ths gases at different temperatures were; 1.21 + 0.38 keel/mole, 1.33 + 0.70 Real/mole, and 1.12 + 0.45 kcal/mole for the CH2 wagging„ C-Cl stretching and CD₂ wagging modes respectively. These values were in good agreement with previously published values.

These results allowed evaluation of this apparatus and experimental design and …

Characterization Of Trihalomethane Formation From Proteins In Chlorinated Water, Robert Aaron Kravitz

Chemistry & Biochemistry Theses & Dissertations

Traditionally humates have been considered the most significant precursor in the formation of trihalomethanes in finished drinking water. This study investigates another potential precursor, namely proteins. The chlorination of aqueous protein solutions yields significant levels of trihalomethanes in terms of the maximum contaminant level (MCL) of 0.100 mg/L imposed by the USEPA. Molar yields for several proteins were determined. The average yield per unit of organic carbon was 0.5% as compared to 0.8% for a humic acid studied. A model protein, bovine serum albumin, was studied extensively to ascertain the effects of total organic carbon, chlorine dose, and time on …

Modulated Piezoreflectivity And The Photoelasticity Of Molecular Crystals, T. Luty, Craig J. Eckhardt

Craig J. Eckhardt Publications

Analysis of the optical response of a molecular crystal undergoing an external, periodic modulation is presented in terms of classical dipole theory. The case of modulated strain is treated in particular and identification of such strain with acoustic phonons with q=0 permits use of lattice dynamical theory to elucidate the acoustic phonon–exciton interaction. It is shown that extrema in the piezomodulated reflectivity (PMR) locate transverse and longitudinal exciton–polariton frequencies under specific experimental conditions. Model calculations demonstrate the great difference in the PMR for strong and weakly coupled systems. Relation of the PMR intensity to the elasto-optic coefficients and the storage …

Electrochemical Studies Of Antimony(Iii) And Antimony(V) In Molten Mixtures Of Aluminum Chloride And Butylpyridinium Chloride, Dhia A. Habboush, Robert A. Osteryoung

Chemistry & Physics Faculty Publications

Electrochemical studies of Sb, Sb(III), and Sb(V) have been camed out in molten mixtures of AlC13 and N-1-butylpyridinium chloride (BuPyCl) at 40 OC, as a function of melt composition. Analysis of measurements in the acidic melts indicates SbC12+ as the dominant species. The reduction of this species on glassy carbon exhibits irreversible behavior. In the basic melts, SbC14- and SbC1,- are believed to be the dominant species. The reduction of Sb(II1) to Sb on glassy carbon also showed irreversible behavior while its oxidation to Sb(W revealed a quasi-reversible behavior. No Sb(II1) oxidation was observed in the acidic melts.

Quantitative Evaluation Of Substituent Effects On Stabilization Energies Of Strained And Unsaturated Molecules, Tyler Arthur Stevenson

Theses

Thermodynamic stabilization energies are presented for a series of monosubstituted vinyl, cyclopropyl, ethynyl, and phenyl compounds. The energies are calculated using ab initio molecular orbital calculations at the 4-31G level, and also with published experimental heat of formation data. Correlation analyses are then attempted with the dual substituent parameter approach with the stabilization energies. The analyses are also attempted with a triple-parameter approach using Topsom's theoretically calculated X, F, and Ro constants. Among the findings are the facts that π-donating substituents correlate well, while π-accepting substituents do not. Indications of the relative sensitivities of hydrocarbon frameworks to substituent electrostatic and …

Synthesis Of Cyclobutenyl Ketals, Atef Z. Boulos

Theses

A series of dialkoxy derivatives of N,N'-di-tert-butyl-2-butylamino-3,3-dichloro-4-dichloromethylene cyclobutenyl carboxamidinum chloride, were prepared by dissolving either Na+ or K+ alkoxide in the appropriate alcohol, or by treatment with potassium hydroxide in the appropriate alcohols. Thus, the dimethoxy, diethoxy, di-isopropoxy, di-n-butoxy, di-tertbutoxy derivatives were obtained.

Measurement Of Low Vapor Pressures: A Kinetic Approach, Samuel Bernard Bliden

Dissertations and Theses

A kinetic model was applied to vapor pressure data obtained by a variable flow method. The vapor pressures of benzoic acid, naphthalene, benzophenone, and phenylhydrazine were measured at temperatures of 293K to 307K. The data are summarized in the data table on the following page. These data were obtained by passing air over a sample of the substance in a tube. The air stream was combusted, and a flame ionization detector was used to measure the mass of CO₂ so obtained. Several different flow rates were used at each temperature with each substance.

Derivatives Of Trifluorovinylsulfur Pentafluoride And F-(Tert-Butyl) Hypochlorite, Jo Ann Marie Canich

Dissertations and Theses

Trifluorovinylsulfur pentafluoride dimerizes to (SF₅CFCF₂)₂ in the presence of cesium fluoride. Two derivatives of trifluorovinylsulfur pentafluoride, SF₅CF(CF₃)C(O)F and SF₅CF(CF₃)C(O)NH₂, were used to prepare the new compounds, SF₅CF(CF₃)CO₂H and SF₅CF(CF₃)CN, respectively. The first was prepared by reacting the SF₅-acid fluoride with water, while the second involved the abstraction of water from the SF₅-amide using P₄O₁₀. The attempted preparation of a bis-pentafluorosulfur ketone and a pentafluorosulfur containing acid anhydride …

High Valent Chromium (V) And Chromium (Vi) Complexes, Harry Bennett Davis

Dissertations and Theses

A new preparative route to the only neutral chromium(V) oxide fluoride, chromium oxide trifluoride, has been accomplished by the reaction of xenon difluoride with chromyl fluoride at high temperature. The chromium oxide trifluoride is produced as crystals which are suitable for single crystal studies. In reactions of chromium oxide trifluoride with alkali and alkaline metal fluorides in anhydrous hydrogen fluoride, new chromium(V) oxide fluoride salts were obtained; these salts were not of high purity due to unknown problems. An attempt to prepare chromium oxide tetrafluoride by the reaction of xenon difluoride with chromyl fluoride in anhydrous hydrogen fluoride failed to …

The Low-Temperature Pyrolysis Of A Nitrated North Dakota Lignite, Dennis Spears

Masters Theses & Specialist Projects

Low-temperature pyrolysis is the thermal degradation of coal in an inert atmosphere at temperatures below 700°C. Coal pyrolysis is well-studied, being a complex mix of many reactions. Pyrolysis is affected by changes in many different process variables, such as temperature, pressure and heating rate. Low-temperature pyrolysis is an old and well-studied process.

Chemical pretreatments have been used to beneficiate conversion processes, inducln pyrolysis. Nitration has not been one of them. Pyrolyzing a nitrated coal would, hopefully, rapidly devolatilize the coal and break up the matrix into more commercially usable products. The nitration procedure developed by The Standard Oil Company minimizes …

H2o2-Tfa-H2so4 Oxidation Of Coal & Coal Model Compounds, Darrell Pierce

Masters Theses & Specialist Projects

The Deno coal oxidation technique was investigated as a tool for the characterization of the aliphatic components of coal. This technique was applied to three high sulfur Kentucky coals:(1) No. 789673, (2) KCER 4002-Elkhorn No. 2, (3) KCER 7122-Ky. No. 12 and a low sulfur coal from Alpha Resources, Inc. Model compound investigations on toluene, ethyl benzene, propyl benzene, bibenzyl, indan and tetralin were also conducted. Different addition modes were investigated using ethyl benzene and diphenylmethane. The stability of the expected aliphatic acid products in the oxidation reagent were also investigated.

The data indicated the following:

1. Pyrite present in high …

   ---

   Go to article

Desulfurization Of Coal Using Carboxylic Acids & Peracids, Dwight Watson

Masters Theses & Specialist Projects

Bituminous coals were desulfurized by leaching in a 325 ml, agitated, autoclave with hot, dilute solutions of carboxylic acids, buffered carboxylic acids, carboxylic salts, and carboxylic salt:alkali combinations. The partial pressure of oxygen was not increased as it was found not to increase the amount of organic sulfur removal. The effect of increasing carboxylic size and decree of desulfurization was studied. Among the carboxylic acids studied, formic acid removed the greatest amount of organic sulfur;and iso-valeric acid removed the greatest percentage of pyritic sulfur. It was found that there is a direct correlation between the amount of organic sulfur removal …

Non-Matrix Corrected Organic Sulfur Determination In Coal By Energy Dispersive X-Ray Spectroscopy, Carol Clark

Masters Theses & Specialist Projects

A method for non-matrix corrected organic sulfur analysis by energy dispersive X-ray spectroscopy has been developed using petroleum coke standards. This technique capitalizes on the fact that when a substance is excited by an electron beam it will emit photons of electromagnetic radiation in the X-ray range. The emitted X-rays are characteristic of the excited elements in the substance. Typically, electron beam microanalysis is a rapid, nondestructive analytical technique to quantitatively measure organic sulfur in coal. The results show good correlation to ASTM values for numerous well characterized bituminous coals with a wide range in total and pyritic sulfur content. …

Corrosion Of Carbon Steel In Synthetic Coal Liquid Wash Waters, Keith Evans

Masters Theses & Specialist Projects

The Potentiodynamic corrosion measuring technique is an electrochemical analytical method which measures corrosion rates of a metal exposed to a corrosive environment.

The corrosion characteristics of carbon steel A1044 in aqueous solutions of aniline hydrochloride,simulating a coal liquid wash water, were determined by this method. The effects of solution velocity and oxygen concentration on the system were also determined.

A bimodal corrosion rate effect was observed in deaerated solutions of 1000 and 5000 ppm chloride as aniline hydrochloride. This effect was interpreted to be the result of the formation of a film on the surface of the specimen.

Spontaneous Heating Of Coal & Electrochemical Measurements Of Corrosion Rates, Bihan Naderi

Masters Theses & Specialist Projects

A new and relatively fast method for measuring the susceptibility of coal to spontaneous heating was studied in this work.

This method is based on the ability of coal to adsorb iron(III) from aqueous solutions. The more iron taken up by the coal, the more susceptible the coal is to spontaneous heating. The relationship holds for most of the coals being analyzed during this research project and for other succeeding ones.

The experimental procedures used and results obtained are discussed. A brief literature survey of other applied methods which have been studied, including a description of many factors affecting the …

Photoaffinity Labeling Of The Antimycin Binding Site In Rhodopseudomonas Sphaeroides, Emily Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to identify the site of interaction of antimycin with the ubiquinone-cytochrome b-c1 oxidoreductase in the photosynthetic bacteria, Rhodopseudomonas sphaeroides. To accomplish this goal, three areas of research were undertaken: the synthesis of a radiolabeled, photoaffinity analog of antimycin, identification of the inhibitory characteristics of this analog, and the photoaffinity labeling of the antimycin binding site. All three areas were accomplished.

The major finding of this study was the identification of an 11,000 dalton polypeptide as the predominantly labeled protein. Although this polypeptide was not exclusively labeled, it was consistently labeled and showed competition …

The Synthesis And Characterization Of Some Transition Metal Complexes Prom Mixtures Of Poly Pyrazolyl Borates, Robert Matthew Alway

Masters Theses

This is a report of the synthesis and separation of transition metal complexes of hydrotris(1-pyrazolyl)- borate and hydrotris(3,5-dimethyl-l-pyrazolyl)borate. These complexes contain a central metal ion and two tridentate ligands, one hydrotris(1-pyrazolyl)borate and one hydrotris(3,5-dimethyl-l-pyrazolyl)borate. Mass spectrometry proved to be an extremely useful technique for identifying products. Many mass spectra are included and discussed extensively.

Complexes containing hydrobis(pyrazole)(3,5-dimethyl -1-pyrazolyl)borate and hydrobis(3,5-dimethyl-l-pyrazole) (pyrazolyl)borate also were synthesised and mass spectra obtained.

Investigation Of Matrix Effects On The Furnace Atomic Absorption Signals Of Chromium, Nickel And Selenium, Susan Marie Viet

Chemistry & Biochemistry Theses & Dissertations

The flameless atomic absorption signals of chromium, nickel and selenium are subject to matrix interferences arising from inorganic salts and anions commonly found in urine. The effects of such salts on the atomic absorption signals were investigated using Polarized Zeeman Effect background correction in conjunction with a detector/readout system capable of resolving absorbance signals in 18 msec readings. Both optical temperature control and current temperature control were employed for each analysis. Peak area, peak height, peak shape and appearance time were compared for matrix-free standards and matrix-containing standards.

The influence of the inorganic salts on the metal analyses was found …

Preparation And Characterization Of Composite Hollow Fiber Reverse Osmosis Membranes By Plasma Polymerization. 2. Reproducibility Of The Plasma Polymerization Process And Durability Of The Resulting Coated Membrane, Y. Matsuzawa, H. Yasuda

Chemistry Faculty Research & Creative Works

The reproducibility of the plasma polymerization process was examined in a semicontinuous coating of hollow fibers, 6 fibers in lengths of approximately 12-15 m, by evaluating the performance of reverse osmosis membranes. The uniformity of the coating along the length of hollow fibers, as well as the reproducibility of the process, was found to be satisfactory when electrodes were conditioned in the actual conditions of plasma polymerization to be employed and plasma polymerization conditions were carefully controlled. The durability of the coated hollow fibers was then investigated in the following test media: hot water, low pH, high pH, and 0.1% …

Preparation And Characterization Of Composite Hollow Fiber Reverse Osmosis Membranes By Plasma Polymerization. 1. Design Of Plasma Reactor And Operational Parameters, P. J. Heffernan, K. Yanaglhara, Y. Matsuzawa, E. E. Hennecke, E. W. Hellmuth, H. Yasuda

Chemistry Faculty Research & Creative Works

Composite hollow fiber reverse osmosis membranes were prepared by depositing a thin layer (10-50 nm) of plasma polymers on hollow fibers with porous walls (made of polysulfone). The coating was carried out in a semicontinuous manner with six strands of substrate fibers. Operational parameters which influence reverse osmosis characteristics of composite membranes were investigated. © 1984, American Chemical Society. All rights reserved.

Magnetic Phase Diagram And Spin Glass Behavior Of Fe₁₋ₓmnₓcl₂·2h₂O, Gary C. Defotis, Christoph Pohl, Spencer A. Pugh, Ekkehard Sinn

Chemistry Faculty Research & Creative Works

The magnetic phase diagram of Fe_1-xMn_xCl₂·2H₂O has been determined. A tetracritical point appears to be present at x ≊ 0.74 and T≊2.8 K. The upper paramagnetic-antiferromagnetic phase boundaries exhibit an unusually rapid descent, and the mixed ordered region below the tetracritical point is quite small. Moreover, regions exhibiting spin glass character also occur in the diagram. The unusually complex behavior is presumably due to the unique constitution of this system: A mixture of two antiferromagnets with different periodicities, competing orthogonal spin anisotropics, competing ferromagnetic and antiferromagnetic near neighbor intrachain exchange interactions, and …

Las Vegas Wash Multispectral Scanner Survey, T. H. Mace, M. V. Olsen, Environmental Protection Agency

Publications (WR)

At the request of the U.S. Bureau of Reclamation, Boulder City, Nevada, the U.S. Environmental Protection Agency's Environmental Monitoring Systems Laboratory at Las Vegas collected multispectral scanner imagery of Las Vegas Wash on October 1, 1982. A combined maximum likelihood classification and editing procedure was used to classify the multispectral scanner imagery into 12 categories of land cover. The classification identified four categories of marsh vegetation, one category of riparian, two categories of mixed scrub, and two desert categories. Turbid water and cultivated land formed an "other" category. Area tabulations were formed by georeferencing the classification to the Universal Transverse …

Hydrogeochemical Aspects Of Surface Mine Reclamation In The Northern Great Plains, Gerald H. Groenewold, Robert D. Koob

Office of the Provost Scholarship

Studies of several coal-mining sites in western North Dakota have resulted in the development of a hydrogeochemical model which accounts for the observed chemical characteristics of subsurface water in undisturbed settings. Critical hydrogeochemical processes include sulfide oxidation, gypsum precipitation and dissolution, carbonate mineral dissolution and cation exchange.

In the semi-arid climate of western North Dakota, the near-surface several meters of the landscape is constantly subjected to alternate wetting/drying. This mechanism is the key to hydrogeochemical evolution of both pore water in the rooting zone and subsurface water that eventually reaches the water table.

Recent refinements in the hydrogeochemical model have …

Alkali Oxides. Analysis Of Bonding And Explanation Of The Reversal Of Ordering Of The 2Σ And 2Π States, Janet N. Allison, Robert J. Cave, William A. Goddard Iii

All HMC Faculty Publications and Research

We analyze the bonding in alkali oxides, MO, for M = Li, Na, K, Rb, and Cs. Using ab initio correlated wave functions we find that the ground state is ²II for M = Li, Na, and K and that the ground state is ²Ʃ^+ for M = Rb and Cs. The origin of this effect is explained.

Nmr Measurements On Intercalated 3r-Tas2.Ix (I=Nh3 And N2h4), N. H. Handly, Juana Vivó Acrivos

Faculty Publications, Chemistry

No abstract provided.

The Synthesis And Characterization Of Some Fluoride Perovskites, An Undergraduate Experiment In Solid State Chemistry, Richard H. Langley, Colleen K. Schmitz, Maureen B. Langley

Faculty Publications

In light of the increasing importance of solid state chemistry, an experiment dealing with at least some aspects of this rapidly expanding area should he included in advanced chemistry laboratories. Herein is described one of the experiments that we have developed to meet this need. This experiment was designed for a senior level integrated chemistry lab taken by all our chemistry majors. Normally six to eight hours are needed to complete this experiment. This experiment deals with the synthesis and characterization of a perovskite. Perovskites were chosen because compounds with this structure are important in solid state technology, and since …

Magnetic And Mössbauer Study Of Metal‐Zeolite Interaction In Catalysts, Thomas Pannaparayil, M. Oskooie-Tabrizi, C. Lo, L. N. Mulay, G. A. Melson, V. U. S. Rao

Chemistry Publications

Molecular sieve aluminosilicates, such as ZSM‐5 and mordenite, when impregnated with highly dispersed Fe, yield catalysts for the selective conversion of coal‐derived syngas (CO+H₂) to liquid hydrocarbon fuels. Fe performs the primary Fischer‐Tropsch (FT) syngas to yield light olefins which are converted by the acidic (H⁺) and shape‐selective function of the zeolite to high octane gasoline components. The physical aspects of the Fe‐mordenite interaction studied by magnetic measurements, Mössbauer, and IR spectroscopy are reported and correlations with the catalytic properties are drawn. Mordenite samples with [SiO₂/Al₂O₃] ratio in the range …