Chemistry Commons^™

Preparation And Application Of Gold-Film On The Surface Of Bacterial-Modified Carbon Paste Electrode, Rong-Zong Hu, Yan-Ping Ruan, Hao Xu, Jin-Kun Fu, Wei-De Zhang, Wen-Yun Hu

Journal of Electrochemistry

A novel method for preparation of gold-film composed of ultra-fine gold particles was reported in this paper. The gold-film was prepared by electrochemical method on the surface of the paste electrode modified with the strain Bacillus sp. D01 which has strong ability to absorb and reduce Au³⁺. In addition, this paper reported an experimental method of determining trace amount of Cu²⁺ in water solution using cathodic stripping analysis to estimate the performances of the obtained gold-film. The experimental results indicated that this new method for preparation of gold-film is simple. The obtained gold-film electrode is stable and …

Electochemical Measuments Of Defective Coatingson Buried Steel Substrates, Shi-Zhe Song, Shi-Jiu Jin, Xiao-Ping Song, Yun-Hai Xu, Jian Li, Yu-Ping Liao, Guang-Sen Lai, Ling-Li Liu

Journal of Electrochemistry

An electrochemical technique to detect the defects and detachments of the protective coating on the steel structures with electrochemical impedance spectroscopy (EIS) was offered. A new parameter K, which was defined as the ratio of the electrode resistance amplitude at a certain frequency to that at minimal frequency was obtained in present paper. The results indicated that the change of K at a certain range of frequency reflected the condition of protective coating. The technique was found to be very useful in estimating the different conditions of protective coating after being applied to the carbon steel samples covered with tar …

Zro2 And Zro2-Y2O3 Coatings Deposited By High Energy Pulse, Wei-Ping Yu, Ye-Dong He, Li-Na Zhang, De-Ren Wang

Journal of Electrochemistry

The basic rule and influence factors on deposition of ZrO₂ and ZrO₂-Y₂O₃ coatings by high energy pulse were studied. After the oxidizing experiment in air at 1 000 for 100 h, it was shown that the oxidation resistance of 18-8 stainless steel was marketly enhanced by depositing ZrO₂ and ZrO₂-Y₂O₃ coatings. The oxidation resistance was increased about 20 times and the oxide scale spallation resistance was increased about 100 times.

Self-Association Of Rifamycin B: Possible Effects On Molecular Recognition, Daniel W. Armstrong, Jeffrey Schneiderheinze, Usha Nair, Linda J. Magid, Paul D. Butler

Chemistry Faculty Research & Creative Works

The macrocyclic antibiotic rifamycin B was found to be highly surface-active and to aggregate in aqueous solution. The aggregational behavior was studied using small-angle neutron scattering (SANS). Aqueous solutions of rifamycin B showed pronounced scattering at both small-length scales (Q ≥ 0.1 Å-1) and at large-length scales (Q ≤ 0.1 Å-1). The larger association colloids appear to be rather open low-density aggregates. The addition of 10% 2-propanol greatly reduces the number and size of the aggregates. Somewhat higher amounts of alcohol appear to completely suppress or eliminate aggregation. The suppression of aggregation coincides with the appearance and enhancement of enantioselective …

Ultrasonically Initiated Free Radical-Catalyzed Emulsion Polymerization Of Methyl Methacrylate (Ii): Radical Generation Process Studies And Kinetic Data Interpretation, H. C.Joe Chou, James O. Stoffer

Chemistry Faculty Research & Creative Works

In the previous work, we have studied the effects of acoustic intensity, argon gas flow rate, surfactant concentration, and initial monomer concentration on polymerization rate, polymer particle number, and polymer molecular weight in the ultrasonically initiated emulsion polymerization of methyl methacrylate. In this study, radical trapping experiments were used to investigate the effect of acoustic intensity, argon gas flow rate, and sodium lauryl sulfate concentration on the extent of free radical generation in aqueous sodium dodecyl sulfate solutions. In these radical trapping experiments, aqueous solutions of sodium lauryl sulfate were ultrasonically irradiated in the presence of a radical scavenger. The …

Plant And Soil Enantioselective Biodegradation Of Racemic Phenoxyalkanoic Herbicides, J. M. Schneiderheinze, Daniel W. Armstrong, Alain Berthod

Chemistry Faculty Research & Creative Works

The biodegradation of the chiral phenoxyalkanoic herbicides 2-(2,4- dichlorophenoxy)propionic aid (2,4-DP) and 2-(4-chloro-2- methylphenoxy)propionic acid (MCPP) was investigated using enantioselective HPLC and chiroptical detection. Racemic mixtures of 2,4-DP and MCPP were applied to three species of turf grass, four species of broadleaf weeds, and soil. Preferential degradation of the S- (-) enantiomer of each herbicide was observed in most species of broadleaf weeds and soil, while the degradation in all species of grass occurred without enantioselectivity. The biodegradation in all systems appeared to follow pseudo first-order kinetics with the fastest degradation occurring in broadleaf weeds, followed by the grasses. The …

The Mean Spherical Approximation For A Dipolar Yukawa Fluid, Douglas Henderson, Dezso Boda, Istvan Szalai, Kwong-Yu Chan

Faculty Publications

The dipolar hard sphere fluid (DHSF) is a useful model of a polar fluid. However, the DHSF lacks a vapor–liquid transition due to the formation of chain-like structures. Such chains are not characteristic of real polar fluids. A more realistic model of a polar fluid is obtained by adding a Lennard–Jones potential to the intermolecular potential. Very similar results are obtained by adding a Yukawa potential, instead of the Lennard–Jones potential. We call this fluid the dipolar Yukawa fluid (DYF). We show that an analytical solution of the mean spherical approximation (MSA) can be obtained for the DYF. Thus, the …

Selective Area Laser Induced Deposition Of Metal Borides, Veronica K. Holmes, Z. C. Zhong, P A. Dowben

Electronic Dissertations and Theses

A novel technique, laser-induced solution deposition (LISD), has been developed for the selective area deposition of rare earth hexaborides. This technique was simple and efficient and combined advantages of chemical vapor deposition (CVD) and electrolytic deposition. The deposition of polycrystalline thin films of hexaborides and sub-borides, such as MB_6, MB_4, and MB₂ (M = Gd, La), occurred by the light-initiated chemical reaction of nido-decaborane (B₁₀H₁₄) and rare earth chlorides in solution. These films grew with a strongly textured axis and had a morphology that was dependent on solvents and irradiation wavelength. Deposition of …

The Binding Of Selected Xenoestrogens To An Estrogen-Binding Fraction, Willie L. Washington

Electronic Dissertations and Theses

The purpose of this study was to test the hypothesis that effects of xenoestrogens may be mediated through a low-affinity estrogen-binding site. This low-affinity estrogen-binding site (EBS) is found in rat uterus. A second receptor, the Type I-(high-affinity-EBS). is also present in the uterus and other tissues. In order to obtain the estrogen-binding fraction-from the uterus, an ammonium sulfate (AS) fractionation was performed on rat-uterine cytosol. Two fractions were made, a 40% AS, which contained the Type I estrogen receptor (ER) and a 70¾ AS fraction that contained the low-affinity estrogen-binding site. These fractions were assayed for their ability to …

Identification And Characterization Of Biological And Volatile Organic Contaminants In Indoor Air In A Governmental State Office Building, Denesia A. Wallace

Electronic Dissertations and Theses

The purpose of this study was to identify and determine the concentrations of targeted inorganic gases and total volatile organic compounds known to exist in indoor air spaces. The Louisiana Department of Environmental Quality (LADEQ) Office Building was selected because of a survey of occupants' symptoms and perceptions of indoor air quality. Collected air samples were analyzed for selected compounds by way of United States Environmental Protection Agency (USEPA) sampling procedures and methods that utilized drager absorption tubes and a gas chromatograph/mass spectrometer. The targeted compounds were nitrogen dioxide, dinitrogen oxide, carbon monoxide, VOCs (volatile organic compounds), formaldehyde, and carbon …

An Immobolized Surfactant Extraction Technique Compatible With High Performance Liquid Chromatography-Ultraviolet Visible Detection, Ming Zhu

Masters Theses & Specialist Projects

Surfactant mediated extractions are analogous to liquid-liquid extractions (LLE) except surfactants are used as extractants instead of organic solvents. The benefit for using surfactants for extractions includes lower toxicity, lower associated costs and direct compatibility with high performance liquid chromatography techniques. In this study, a novel immobilized surfactant extraction method was developed. In this method, the cationic alklytrimethylamrnonium surfactants are immobilized onto a strong cationic exchange resin through ion exchange. This surfactant-resin material is placed in a column and aqueous solutions containing analytes are passed through. The analytes are retained by the long carbon chain of the surfactant molecules and …

Reductive Dehydroxy Coupling Of 2-(Hydroxymethyl)Indenes To Prepare Ethano-Bridged Bis(2-Indenyl) Ansa-Titanocenes, Hasan Palandoken, Justin K. Wyatt, Shawn R. Hitchcock, Marilyn M. Olmstead, Michael H. Nantz

Chemistry and Biochemistry

New examples of ansa-titanocenes derived from 1,2-bis(2-indenyl)ethane have been prepared. The titanium-mediated reductive coupling of 2-(hydroxymethyl)indenes provided a convenient method for substrate dimerization. Alkyl substitution of the indene ring at C(3) improved the regioselectivity of the reductive coupling to provide the ethylene bis(2-indenyl)ansa-ligands in 29–62% yield.

Analysis Of Fats And Fat-Soluble Components In Foods Using Supercritical Fluid Extraction And Chromatographic Techniques, Sneha Patel

Masters Theses & Specialist Projects

The purpose of this study was to develop experimental procedures for the extraction of fats from common foods using SFE and to determine by chromatographic techniques the fat-soluble components that are extracted with the fats. In this study various food samples were examined including french fries from Wendy's, McDonald's and Burger King, as well as potato chips, peanut butter and donuts. Soxtec extraction was used as the standard method for comparison of results (percentage of fat) obtained from SFE. Gas chromatography and gas chromatography/mass spectrometry were used for the determination of fat-soluble components (fatty acids), after extraction of fat from …

Surface Composition Of CoXNi1-XO Solid Solutions By X-Ray Photoelectron And Auger Spectroscopies, M. W. Nydegger, G. Couderc, Marjorie Langell

Marjorie A. Langell Publications

The surface and bulk compositions of the mixed metal oxide Co_xNi_1-xO have been compared over the entire range of stoichiometry 0 ≤ x ≤ 1. The materials, which were formed as polycrystalline solid solutions, were shown to be well-ordered and homogeneous in the bulk, but tend to deviate in their surface composition for x > 0.6. Auger and X-ray photoelectron spectroscopy gave comparable results and indicated that the surface composition for samples showing deviation from bulk stoichiometry was compatible with the formation of a spinel-like NiCo₂O₄ surface phase. XPS binding energies and spectral …

An On-Line Test For Polycyclic Aromatic Hydrocarbons In The Flue Gas From Coal Combustion In An Fbc System, Wenjun Han

Masters Theses & Specialist Projects

Polycyclic Aromatic Hydrocarbons (PAHs) are environmental pollutants that have received considerable attention because of their carcinogenic and mutagenic effects. Due to the extensive amount of data suggesting the hazards of these compounds, 16 PAHs are on the Environmental Protection Agency (EPA) Priority Pollutant List. These compounds are often emitted into the atmosphere by way of combustion processes. Thus, analysis of these compounds during coal combustion is an important task. Three 1000-hour coal combustion burns were performed using the 0.1 MW (0.3 m) bench-scale Fluidized Bed Combustor (FBC) in the Combustion Laboratory at Western Kentucky University. The data for this thesis …

Planarity Of Para Hexaphenyl, Suchismita Guha, Wilhelm Graupner, Roland Resel, Meera Chandrasekhar, H. R. Chandrasekhar, Rainer Glaser, Günther Leising

Chemistry Faculty Research & Creative Works

We present experimental and theoretical findings on the geometry of polycrystalline para hexaphenyl via Raman scattering. The planarity of the molecule is affected by hydrostatic pressure and temperature. Our studies indicate that the potential energy curve which governs the torsional motion between neighboring phenyl rings is "W" shaped. We determine the activation energy to promote the molecule from a nonplanar to a planar state to be 0.04 eV, in good agreement with our quantum chemical calculations. From the relative intensities of the 1280cm^-1 to the 1220cm^-1 Raman modes we show that high pressure planarizes the molecules, modifying the …

Liquid Reaction Apparatus For Surface Analysis, Charles C. Chusuei, T. S. Murrell, J. S. Corneille, M. G. Nooney, S. M. Vesecky, L. R. Hossner, D. W. Goodman

Chemistry Faculty Research & Creative Works

A design for a liquid reaction apparatus is described which allows surfaces prepared in ultrahigh vacuum (UHV) to be reacted with solutions of a wide pH range under dry nitrogen atmosphere and subsequently returned to UHV for surface analysis.

Insight Into The Selectivity Of Molecular Imprinted Polymers, Thomas Patrick O'Brien

Seton Hall University Dissertations and Theses (ETDs)

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Thermodynamic And Binding Studies Of Ligand-Carcinogen Dna Targets, Qianying Liang

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.

Analytical Sfe: Optimization And Applications, Sohita Patel

Seton Hall University Dissertations and Theses (ETDs)

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Thermal Decomposition And Combustion Of Γ-Irradiated Polyamide 6 Containing Phosphorus Oxynitride Or Phospham, A. I. Balabanovich, Sergei V. Levchik, Galina F. Levchik, W. Schnabel, Charles Wilkie

Chemistry Faculty Research and Publications

Polyamide 6 (PA-6) containing the fire retardants phosphorus oxynitride ((PON)_m) or phospham ((PN₂H)_n) was exposed to ⁶⁰Co-γ-rays (absorbed dose: 1.0–4.0 MGy). The irradiation led to crosslinking of the polymer which caused an increase in the char yield and a decrease in the flammability of the polymer. The combustion behavior was strongly affected by irradiation: dripping was totally prevented in the case of system PA-6/(PN₂H)_n and strongly retarded in the case of system PA-6/(PON)_m. The thermal stability of the system PA-6/(PN₂H)_n decreased with increasing absorbed dose …

Thermal Degradation Of Polystyrene, Poly(1,4-Butadiene) And Copolymers Of Styrene And 1,4-Butadiene Irradiated Under Air Or Argon With 60co-Γ-Rays, W. Schnabel, Galina F. Levchik, Charles Wilkie, David D. Jiang, Sergei V. Levchik

Chemistry Faculty Research and Publications

⁶⁰Co-γ-irradiated samples of polystyrene (PSt), poly(1,4-butadiene), (PBD), and two poly(styrene-co-butadiene)s containing 25 and 75% BD were subjected to thermogravimetric analysis (TGA), in the presence and absence of O₂. In the case of PSt the irradiation caused a significant shift in T_onset, the onset temperature for mass loss, to higher temperatures, whereas in the cases of the BD-containing polymers irradiation caused a decrease in T_onset (oxic irradiation) or had little or no effect on T_onset (anoxic irradiation). The amount of non-volatile residue formed in the cases of BD-containing polymers was augmented by …

Use Of Evolutionary Factor Analysis In The Spectroelectrochemistry Of Escherichia Coli Sulfite Reductase Hemoprotein And A Mo/Fe/S Cluster, Robert L. Keesey, Michael D. Ryan

Chemistry Faculty Research and Publications

The deconvolution of spectroelectrochemical data is often quite difficult if the spectra of intermediates are not known. Factor analysis, however, has been shown to be a powerful technique which can make it possible to deconvolute overlapping spectra. In this work, evolving factor analysis will be used to determine the number of intermediates and the spectra of those species for two typical spectroelectrochemical experiments:  linear scan voltammetry and chronoabsorptometry in a thin-layer cell. The first system was the reduction of E. coli sulfite reductase hemoprotein (SiR-HP). Principal factor analysis indicated that three species were present. By using evolving factor analysis, …

The Role Of Iron And Reactive Oxygen Species In Particulate Air Pollution-Dependent Biochemical And Biological Activities, Kevin Richard Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particulate air pollution is known to exacerbate respiratory diseases, such as asthma and chronic obstructive pulmonary disease, in humans. It has been proposed that transition meta ls from inhaled particles may play a role in this exacerbation by generating radical species leading to damage in the lungs.

The aim of this research was to determine the role that iron from particulate air pollution played in the generation of reactive oxygen species and subsequently the induction of inflammatory mediators in cells in culture. The production of reactive oxygen species by particulate air pollution was found to be dependent on the mobilization …

Growth Of Nanotubes For Probe Microscopy Tips, Jason H. Hafner, Chin Li Cheung, Charles M. Lieber

Barry Chin Li Cheung Publications

Carbon nanotubes, which have intrinsically small diameters and high aspect ratios and which buckle reversibly, make potentially ideal structures for use as tips in scanning probe microscopies, such as atomic force microscopy (AFM)^{1, 2, 3, 4}. However, the present method of mechanically attaching nanotube bundles for tip fabrication is time consuming and selects against the smallest nanotubes, limiting the quality of tips. We have developed a technique for growing individual carbon nanotube probe tips directly, with control over the orientation, by chemical vapor deposition (CVD) from the ends of silicon tips. Tips grown in this way may become …

Defective Interleukin (Il)-18-Mediated Natural Killer And T Helper Cell Type 1 Responses In Il-1 Receptor-Associated Kinase (Irak)-Deficient Mice, Palanisamy Kanakaraj, Karen Ngo, Ying Wu, Ana Angulo, Peter Ghazal, Crafford A. Harris, John Siekierka, Per A. Peterson, Wai Ping Fung-Leung

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Interleukin (IL)-18 is functionally similar to IL-12 in mediating T helper cell type 1 (Th1) response and natural killer (NK) cell activity but is related to IL-1 in protein structure and signaling, including recruitment of IL-1 receptor-associated kinase (IRAK) to the receptor and activation of c-Jun NH2-terminal kinase (JNK) and nuclear factor (NF)-κB. The role of IRAK in IL-18-induced responses was studied in IRAK-deficient mice. Significant defects in JNK induction and partial impairment in NF-κB activation were found in IRAK-deficient Th1 cells, resulting in a dramatic decrease in interferon (IFN)-γ mRNA expression. In vivo Th1 response to Propionibacterium aches and …

Aluminum And Phosphorus Separation: Application To Preparation Of Target From Brain Tissue For 26Al Determination By Accelerator Mass Spectrometry, Russell D. Brauer, J. David Robertson, Pankaj Sharma, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Acid digested brain containing 4 mg added ²⁷Al was ashed at 1000°C to prepare an Al₂O₃ target for accelerator mass spectrometry (AMS) analysis of ²⁶Al. A glass-like material usually resulted which was thought to be aluminum (Al) oxyphosphate. The separation of Al and phosphate was investigated. Al, but not phosphate, was bound by a cation exchange resin (AG 50-X8). Hydrofluoric acid eluted the Al from the resin. Removal of phosphate from acid digested brain by this method produced an amorphous material after ashing that was easier to recover from the porcelain crucible and had a …

Synthesis Of A Novel ??-Amino Acid Capable Of Stabilizing A 310-Helix Via Side-Chain Salt-Bridging, Reema K. Thalji

Honors Capstones

No abstract provided.

Structural, Magnetic, And Mössbauer Spectral Properties Of Pr₂Fe₁₇Hₓ Where X Is 1, 2, And 3, Fernande Grandjean, Dimitri Hautot, Gary J. Long, Olivier Isnard, Salvatore Miraglia, Daniel Fruchart

Chemistry Faculty Research & Creative Works

The 295 K unit cell parameters of Pr₂Fe₁₇H_x, where x is 0, 1, 2, and 3, have been determined by x-ray diffraction. Upon hydrogenation, the unit cell volume expands anisotropically with a 1.2% expansion of the a axis and no expansion of the c axis for x=3. The Curie temperatures are 286, 374, 440, and 484 K, for x=0, 1, 2, and 3, respectively. The Mössbauer spectra have been measured between 4.2 and 295 K, and the spectra of Pr₂Fe₁₇H and Pr₂Fe₁₇H₂, obtained above …

Atomic Structure And Magnetism Of Ordered And Disordered Al₀.₅Fe₀.₅₋ₓmnₓ Alloys, V. G. Harris, D. J. Fatemi, K. B. Hathaway, Q. Huang, Amitabh Mohan, Gary J. Long

Chemistry Faculty Research & Creative Works

The equiatomic FeAl alloy has been modified by partial substitution of Mn for Fe, and its magnetic and structural properties investigated by neutron diffraction (ND), x-ray absorption fine structure (XAFS) spectroscopy, Mössbauer spectroscopy (MS), and SQUID magnetometry both for the ordered (B2) and disordered states. The unit cell volume is measured to increase linearly with Mn concentration. XAFS measurements indicate local structural displacements occur at the Mn sites in both ordered and disordered states that may act to frustrate long-range magnetic order (LRMO). Although MS and ND show no evidence of LRMO, SQUID magnetometry indicates an induced movement in the …