Digital Commons Network^™

Investigations Of Substitution Of Bi And Tl For Rare Earth Elements In Superconducting Rba2cu3oy, Jian Tang

Theses

Substitution of some other elements for rare earth or yttrium in high-T_c superconducting RBa₂Cu₃O_y compounds (R = Y, Nd, etc.) may improve chemical and physical properties of the materials, shed light on the superconducting mechanism of the new materials, and help to find new superconducting materials with even higher transition temperatures.

Bi³⁺ and Tl³⁺ have been reported earlier to result in higher T_c's in the related layer-structure compounds. The effect of electronegativity on superconductivity could be studied if substitution of Bi or Tl for Y or other rare earth elements …

X-Ray Study Of The Crystallization Processes In Amorphous (Zro. 64ni0. 36) 1-Xalx Alloys. [Abstract], W. D. Bruton, T. O. Callaway, Richard H. Langley, B. H. Zhang, D. G. Naugle

Faculty Publications

The short range order in (Zr_0.64Ni_0.36)_1−xAl_x metallic glasses for values of x between 0 and 0.25 was investigated using X-ray diffraction. X-ray intensity patterns and the derived structural functions for the as-quenched samples differed only slightly with the change in aluminum concentration, suggesting that the addition of aluminum does not significantly alter the relative coordination of the zirconium and nickel atoms. Only the first two alloys in the series (x = 0, 0.05) exhibited multiple transitions in the DSC thermograms. The intermediate phase for the x = 0.05 alloy has an …

Interaction Of Pyridine With Ba2casr2cu20x, Juana Acrivos, C. Lin

Faculty Publications, Chemistry

The adsorption of of pyridine on single crystals of Bi2CaSr2Cu2Ox has been followed by optical microscopy on the crystal surface, where a blue solution is formed as a first step of reaction. The superconducting properties of the single crystal and its structure were monitored by ac susceptibility and by x-ray diffraction measurements. The results (as observed by the growth of the blue solution boundary versus time with Daa = 3.7x10-10 cm2/s.) indicate that the reaction starts at nucleation sites on the basal surface of the crystal. The edges of the crystal also show blue nucleation sites but these do not …

Aspects Of Sporinite Chemistry, Michael A. Kruge, John C. Crelling, Edwin J. Hippo, Stephen R. Palmer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

With the recent advent of the ability to separate coal into maceral concentrates of high purity, the individual constituents of coal can now be analyzed separately, without their mutual interference, giving a much better understanding of the macromolecular structure of coal. The sporinites from two Pennsylvanian age coal samples (Illinois Basin, U.S.A.) were studied, one from a vitrinite-rich high-volatile bituminous coal, the other from a liptinite-rich high-volatile bituminous coal of slightly higher rank. Sporinites were isolated from each coal by density gradient centrifugation. The sporinite of the vitrinite-rich coal was compared chemically and petrographically with the parent coal and with …

Second Coefficient Of Viscosity In Air, Robert L. Ash, Allan J. Zuckerwar, Zhonquan Zheng

Mechanical & Aerospace Engineering Faculty Publications

Acoustic attenuation measurements in air were analyzed in order to estimate the second coefficient of viscosity. Data over a temperature range of 11 C to 50 C and at relative humidities between 6 percent and 91 percent were used. This analysis showed that the second coefficient of viscosity varied between 1900 and 20,000 times larger than the dynamic or first coefficient of viscosity over the temperature and humidity range of the data. In addition, the data showed that the molecular relaxation effects, which are responsible for the magnitude of the second coefficient of viscosity, place severe limits on the use …

Novel Chemical Preparative Route For Semiconducting Mose2 Thin Films, K. C. Mandal, O. Savadogo

Faculty Publications

No abstract provided.

Dynamic And Spectroscopic Studies Of Triplet State Nitrogen, Scott M. Hurst

Dissertations

No abstract provided.

On-Road Carbon Monoxide And Hydrocarbon Remote Sensing In The Chicago Area, Donald H. Stedman, Gary A. Bishop, James E. Peterson, Paul L. Guenther, Iain F. Mcvey, Stuart P. Beaton

Fuel Efficiency Automobile Test Publications

No abstract provided.

In Situ Infrared Evidence For The Electrochemical Incorporation Of Hydrogen Into Si And Ge, K. C. Mandal, F. Ozanam, J.-N. Chazalviel

Faculty Publications

No abstract provided.

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.

32nd Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 32nd annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 29 - August 3, 1990.

Ua66/7/3 Coal & Fuel Characterization Laboratory: The First Ten Years, Wku Chemistry

WKU Administration Documents

Report of work completed in the first ten years of the Coal & Fuel Characterization Laboratory.

X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim

Theses

The orientation of soil contaminants such as chromium is altered during microwave heating. The SEM and EDS were utilized in the study. The nature of the orientation is related to the heating time. This results in immobilizing the contaminant in leaching tests. The non-leachibility was related to the reactivity of the chromium salt with the soil hematite phase (Fe2O3) during the microwaving. This was proved By the X-ray diffraction analysis. The spectrums obtained from 30 and 60 minutes microwaved samples were identical in the crystal phases and were significantly different from the contaminated unheated sample.

Removal Of Heavy Metal Ions From Wastewater By Foam Flotation, Xue-Jun Tang

Theses

The foam flotation technique was used to remove Cr³⁺, Cr⁶⁺, Cu²⁺, Zn²⁺, Co²⁺, and Nz²⁺ from solution The simulated wastewater contained 20 - 50 ppm of each of these ions. Fe³⁺ is added into wastewater as coagulant to produce floc. These dissolved metal ions are adsorbed onto the floc and/or coprecipitate with them. The floc can be then removed from solution by foam flotation. Under optimal conditions, such as pH=6.3 - 7.4, Fe³⁺=160 ppm for hexavalent Chromium or 90 ppm for others and Lauryl Sulfate=90 ppm, …

Two-Dimensional Gel Electrophoretic Analysis Of Cellular Proteins From Escherichia Coli In The Presence Of Mutated And Homologous Genes For 4.5s Rna, Michael O'Loughlin

Senior Scholar Papers

4.5S RNA is a small. stable, required molecule in Escherichia coli whose precise function is not known. Previous evidence suggests an involvement with the ribosome during translation. In this study, four base insertion and four base deletion mutations were constructed in a plasmid borne copy of the 4.55 RN A gene. These copies and two homologous genes from Pseudomonas aeruginosa and Thermus thermophilus were transformed into an E. coli strain which then had its only wild-type 4.5S RNA gene inactivated. In order to assess the effect of the alternative gene copies. the patterns of proteins synthesized in the presence of …

An Analysis Of On-Road Remote Sensing As A Tool For Automobile Emissions Control, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

Final report to the Illinois Department of Energy and Natural Resources, ILENR/RE-AQ-90/05

Studies Of Nitro-Pah On Ambient Air Particulate Matter, Yadan Wang Chen

Theses

A rapid, simple method for routine trace analysis of four isomeric nitropolycyclic aromatic hydrocarbons (nitro-PAH) (1-nitropyrene, 2-nitropyrene, 2-nitrofluoranthene and 3-nitrofluoranthene) in ambient air particulate matter is described. Two types of air particle sample (TSP and IP10) were collected and particle extracts were prefractionated by thin layer chromatography and the appropriate zones of interest analyzed by reversed-phase HPLC with UV and fluorescence detection. The study of Zn/Si post-column reaction chamber and oxygen scrubber for catalytic reduction of target compounds is also described. Six nitro-PAH compounds were identified in TSP and five in IP10 air particle samples. The results of identification and …

Synthesis Of Strained Lactams And Study Of Their Energetics And Bonding, Jung-Chou Tsai

Theses

In order to measure nitrogen and oxygen ionization energies of planar and nonplanar lactams, four compounds were synthesized successfully. The comparison of these ionization energies provides a qualitative insight into how the charge distribution of strained lactams varies with molecular geometry. Of special interest was the different ability of amides to exhibit resonance, monitored most sensitively by the core electron energy of nitrogen in the compounds. The nitrogen core (1s) ionization energies for the two nonplanar amides, 1,3-di-tert-butyl aziridinone (405.00 ev) and 1-azabicyclo[3.3.1]nonan-2-one (405.47) each having pyramidal nitrogens, indicated a nitrogen more negative than that in the comparable planar amide. …

Characterization Of Organic Sulfur Compounds In Coals And Coal Macerals, Stephen R. Palmer, Edwin J. Hippo, Michael A. Kruge, John C. Crelling

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Peroxyacetic acid oxidation has been used to investigate the type and distribution of organic sulfur species in samples of vitrinite, sporinite and inertinite, separated from the Herrin No.6 and an Indiana No.5 coal seam. It was established that organic sulfur species were selectively preserved during oxidation and their analysis led to some of the first sulfur-33 NMR spectra obtained for coal. The effects of maceral separation processes on model compounds were also studied. Results from our studies support the following conclusions: 1). Different macerals have different distributions and types of organic sulfur species. 2). Organic sulfur compounds in coal occur …

Study Of Deposition Methods For Silicon Powder, Kamesh V. Gadepally, Kevin B. Tennal, Roger M. Hawk, Al Robles, James A. Gribel

Journal of the Arkansas Academy of Science

Silicon powder tends to agglomerate at normal atmospheric conditions and is, hence, difficult to aerosolize. Several methods of aerosolizing silicon powder and finally depositing it on various substrates were investigated. This paper presents the investigated methods of aerosolization. The electrostatic spray coating used in dry paint application was found to be the most suitable. The general merits of this method and its use for silicon powder deposition to form films are discussed.

Improving The Analytical Recovery Of Radiostrontium From Environmental Samples, Luz Selenia Acosta

Retrospective Theses and Dissertations

No abstract provided.

Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin

Faculty Publications

A water-soluble carbodiimide has been used to end-graft aminated poly (ethylene oxide)(PEO) chemically onto colloidal polystyrene particles. Two particle sizes (115 and 347 nm diameter) and two PEO molecular weights (112 000 and 615 000 g mol^–1) were combined to give suspensions with four different ratios of polymer layer thickness to particle radius. Electrophoresis demonstrated that the PEO was grafted, not just adsorbed. Dynamic light scattering showed that the adsorbed and grafted layers had similar structures and that non-ionic surfactant perturbed the PEO configurations. Steady shear and oscillatory rheometry indicated that long-ranged polymeric forces between particles governed the …

Plasma Surface Treatment On Nylon Fabrics By Fluorocarbon Compounds, Yu Iriyama, Takeshi Yasuda, D. L. Cho, H. Yasuda

Chemistry Faculty Research & Creative Works

Nylon fabrics were treated by low temperature fluorocarbon plasmas. All of the fluorocarbon plasmas applied altered the surface of nylon fabrics to be hydrophobic and water‐repellent. The durability of hydrophobicity and water repellency was examined by measurements of the water contact angle, the water droplet rolling‐off angle, and the breakthrough water pressure after plasma‐treated fabrics were washed. It was found that the structure of starting fluorocarbon and the plasma energy input were important factors in the durability. After washing, surface dynamics were investigated on different drying conditions. It was found that chemical composition and water repellency were dependent on drying …

The Effects Of Crosslinking On The Stability And Autoxidation Rate Of Human Hemoglobin A, Thao Yang

Dissertations

No abstract provided.

A Study Of The Hydration Properties Of Selected Laser Dye Aerosols Including Continuous-Flow Parallel Plate And Alternating-Gradient Thermal Diffusion Cloud Chamber Measurements In The High Supersaturation Regime, Donald E. Hagen, Max B. Trueblood, Darryl J. Alofs

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Hydration Behavior of Aerosols made Up of Various Fluorescent Dyes when Exposed to Water Saturation or Supersaturated Conditions Has Been Studied. Critical Supersaturation Spectra Are Reported. the Dyes Are Found to Behave as High Molecular Weight Ionic Compounds that Obey Kohler Theory. their Relevant Kohler Parameters Are Measured. This Study Makes Use of and Compares Results from the Isothermal Hazecontinuous-Flowand Alternating-Gradient Thermal Diffusion Cloud Chambers. the Ability of the Continuous-Flow Thermal Diffusion Chamber to Operate Correctly at High Supersaturations is Shown. © 1990 Elsevier Science Publishing Co., Inc.

Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton

Chemistry Faculty Publications

Insects have been major pests of humankind at least since the beginning of recorded history. To this day insects continue to cause problems in domestic, agricultural, and health situations. It is no wonder that people have continually sought new solutions to controlling insect pests. Even when new control methods are discovered and established, insects evolve into resistant species so that the method is only of real value for a few brief years. Modern science and technology are now enabling scientists to tear away the fabric that has so long masked physiological and biochemical events critical to insects. Armed with this …

Sans From Tetradecylpyridinium Bromide Based Microemulsions, Paul M. Lindemuth, Boualem Hammouda, Raymond L. Venable

Chemistry Faculty Research & Creative Works

Small-angle neutron scattering is used to investigate tetradecyl pyridinium bromide/pentanol/heptane/heavy water microemulsions in the water-in-oil (W/O) microemulsion phase diagram region. The heavy water content is increased while the other components (surfactant, cosurfactant, hydrocarbon) are kept constant. With use of a simple model assuming spherical micelles interacting with a hard-sphere potential (Percus-Yevick model), aggregate sizes and packing fractions have been extracted and found to agree with values determined from the mixing conditions. These experiments clearly show the transition from the single-particle (heavy water + Stern layer droplet) scattering regime at low water concentration to the mixed single/interdroplet scattering regime when the …

Study Of Acetone Extractable Organic Matter From Airborne Particulate Matter From An Urban Site, Wenhui Wu

Theses

Two seasonal periods (Winter 1988; Summer 1988) of daily Newark urban air samples were collected on glass fiber filters. Each filter was first extracted with dichloromethane and subsequently with acetone. Quarterly composites of each were then tested for mutagenicity. The results of the analysis of the less polar dichloromethane extracts were reported in the thesis of Junghen Lwo. A modified fractionation scheme involving acid-base partitioning and silica gel column chromatography has been used as the first step in the bioassay-directed search for significant levels of mutagenic compounds in extracts of inhalable (IP 10) ambient air particulates. The biologically "hot" fractions …

31st Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 31st annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 30 - August 4, 1989.

Synthesis Of Highly-Strained Gem-Difluoro Compounds By Reaction Of Difluoromethylene With Cycloalkenes, Deyi Yang

Theses

Trans-Cyclooctene is thought to be more reactive than cis-cyclooctene due to its trans-structure. When cis or trans-clooctene reacts with difluormethylene (:CF₂), trans-9,9-difluorobicyclo[ 6,1,0] nonane was generated in much higher yield than cis-9,9-difluorobicyclo[6,1,0]nonane. [PhCF₃P⁺CF₂Br]Br^- was chosen to be the difluoromethylene precursor in this study. The reason was that the reaction condition for trans-cyclooctene and :CF₂ should be at low temperature. Only [PhCF₃P⁺CF₂Br]Br^- could generate CF₂ at lower temperature (e.g. room temperature). We succeeded in the synthesis of trans-9,9-difluorobicyclo[6,1,0]nonane and its cis isomer and …