Chemistry Commons^™

Rhizopine Synthesis – Potential Mediators For Nitrogen Fixation In Legume Plants, Venkat Reddy Guduru

Masters Theses

This research project focused on novel and efficient synthetic approaches of inosamine derivatives (rhizopines). The preparation of specific rhizopines would help elucidate the microbial pathway of rhizopine catabolism and degradation, and determine the role of corresponding genes during nitrogen fixation. We have investigated regio - and stereoselective transformations of myo-inositol derivative 28 utilizing an organostannane as key intermediate towards rhizopine 1a. The synthesis involved several protection and deprotection strategies to control competing reactivities of six hydroxyl groups of myo-inositol. Rhizopine 1a was prepared efficiently as a single isomer in 8 steps and 13% yield by controlling reactions …

Effect Of Antioxidants On Cadmium Induced Oxidative Stress And Signal Transduction, Deepti Goel

Masters Theses

A study was done to establish if reactive oxygen species (ROS) participate in the signal transduction pathway through which cadmium induces gene transcription. Cadmium has become a concern in the health care community in the past few years as evidence suggests that cadmium can induce the development of tumors, influence cell signaling and cause damage to organs, tissue, cells and DNA. The mechanism by which cadmium exerts its action on cellular processes or induces toxicity is however unclear although there is evidence to suggest that ROS play a role. Our laboratory is interested in understanding the mechanisms of differentially regulated …

Copper Exchange Studies Between The First And Fourth N-Terminal Metal-Binding Domains Of Wilson Disease Atpase, Jennifer Bunce

Masters Theses

The human copper-transporting ATPase Wilson's disease protein was one of the first proteins shown to be actively involved in cellular copper homeostasis. The protein includes six N-terminal metal binding domains. The individual capabilities of the domains to bind and transfer copper are not yet fully understood. Each metal-binding domain is about 72 amino acid residues long and contains the conserved binding motif GMTCXXC, of which the cysteines are involved in the copper coordination. Studies have shown that the protein binds six copper atoms suggesting the potential involvement of each metal-binding domain. Separate functional roles for the latter domains have been …

The Armstrong Chemical Bond, Armstrong Atlantic State University

Chemical Bond Newsletter (Archived)

No abstract provided.

26Al-Containing Acidic And Basic Sodium Aluminum Phosphate Preparation And Use In Studies Of Oral Aluminum Bioavailability From Foods Utilizing 26Al As An Aluminum Tracer, Robert A. Yokel, Aaron A. Urbas, Robert A. Lodder, John P. Selegue, Rebecca L. Florence

Pharmaceutical Sciences Faculty Publications

We synthesized ²⁶Al-containing acidic and basic (alkaline) sodium aluminum phosphates (SALPs) which are FDA-approved leavening and emulsifying agents, respectively, and used them to determine the oral bioavailability of aluminum incorporated in selected foods. We selected applicable methods from published syntheses (patents) and scaled them down (∼3000- and 850-fold) to prepare ∼300–400 mg of each SALP. The ²⁶Al was incorporated at the beginning of the syntheses to maximize ²⁶Al and ²⁷Al equilibration and incorporate the ²⁶Al in the naturally-occurring Al-containing chemical species of the products. Near infrared spectroscopy (NIR) and X-ray powder diffraction (XRD) were used …

Strongly Decoupled Europium And Iron Vibrational Modes In Filled Skutterudites, Gary J. Long, Raphäel P. Hermann, Fernande Grandjean, Ercan E. Alp, Wolfgang Sturhahn, Charles E. Johnson, Dennis E. Brown, Olaf Leupold, Rudolf Rüffer

Chemistry Faculty Research & Creative Works

The europium partial vibrational density of states (DOS) in EuFe₄Sb₁₂ and the iron partial vibrational DOS in both EuFe₄Sb₁₂ and Ce⁵⁷Fe₄Sb₁₂ have been obtained by nuclear inelastic scattering. The results reveal the strong independence of the iron and rare-earth vibrational modes. The cage filling europium only participates significantly to the low-energy local vibrational modes. The force constants have been obtained from the measured probability of nuclear absorption. The energies of the peaks in the europium and iron DOS are in excellent agreement with the calculated DOS in LaFe_{4 …}

How To Choose One-Dimensional Basis Functions So That A Very Efficient Multidimensional Basis May Be Extracted From A Direct Product Of The One-Dimensional Functions: Energy Levels Of Coupled Systems With As Many As 16 Coordinates, Richard Dawes, Tucker Carrington Jr.

Chemistry Faculty Research & Creative Works

In this paper we propose a scheme for choosing basis functions for quantum dynamics calculations. Direct product bases are frequently used. The number of direct product functions required to converge a spectrum, compute a rate constant, etc., is so large that direct product calculations are impossible for molecules or reacting systems with more than four atoms. It is common to extract a smaller working basis from a huge direct product basis by removing some of the product functions. We advocate a build and prune strategy of this type. the one-dimensional (1D) functions from which we build the direct product basis …

Controlling The Morphology Of Composite Latex Particles, Douglas Holmes

Inquiry Journal 2005

No abstract provided.

Methods For Fabricating Microarrays Of Motile Bacteria, Sergey Rozhok, Clifton K. -F. Shen, Pey-Lih H. Littler, Zhifang Fan, Chang Liu, Chad A. Mirkin, Richard C. Holz

Chemistry Faculty Research and Publications

Motile bacterial cell microarrays were fabricated by attaching Escherichia coli K-12 cells onto predesigned 16-mercaptohexadecanoic acid patterned microarrays, which were covalently functionalized with E. coli antibodies or poly-L-lysine. By utilizing 11-mercaptoundecyl-penta(ethylene glycol) or 11-mercapto-1-undecanol as passivating molecules, nonspecific binding of E. coli was significantly reduced. Microcontact printing and dip-pen nanolithography were used to prepare microarrays for bacterial adhesion, which was studied by optical fluorescence and atomic force microscopy. These data indicate that single motile E. coli can be attached to predesigned line or dot features and binding can occur via the cell body or the flagella of bacteria. Adherent bacteria …

Synthesis Of Cyclopropanes Via Organoiron Methodology: Preparation And Rearrangement Of Divinylcyclopropanes, Nathaniel J. Wallock, William A. Donaldson

Chemistry Faculty Research and Publications

Addition of alkenyl Grignard reagents to (1-methoxycarbonylpentadienyl)iron(1+) cation generates the corresponding (2-alkenylpent-3-en-1,5-diyl)iron complexes. Oxidatively induced-reductive elimination of these complexes gives divinylcyclopropanes which can undergo subsequent Cope rearrangement to give 1,4-cycloheptadienes.

Evaluation Of Fluorapatite As A Waste-Form Material: First Quarter Report, January 1 - March 31, 2005, Dennis W. Lindle, Oliver Hemmers

Separations Campaign (TRP)

Fluorapatite, fluorinated calcium phosphate, has been identified as a potential matrix for the entombment of the zirconium fluoride fission product waste stream from the proposed FLEX process. If the efficacy of fluorapatite-based waste-storage can be demonstrated, then new and potentially more-efficient options for handling and separating high-level wastes, based on fluoride-salt extraction, will become feasible. This proposal will develop a dual-path research project to develop a process to fabricate a synthetic fluorapatite waste form for the ZrF₄, FP waste stream, characterize the waste form, examine its performance under environmental conditions, and correlate the behavior of the waste form …

Determining The Optimal Size Of Small Molecule Mixtures For High Throughput Nmr Screening, Kelly A. Mercier, Robert Powers

Robert Powers Publications

High-throughput screening (HTS) using NMR spectroscopy has become a common component of the drug discovery effort and is widely used throughout the pharmaceutical industry. NMR provides additional information about the nature of small molecule-protein interactions compared to traditional HTS methods. In order to achieve comparable efficiency, small molecules are often screened as mixtures in NMR-based assays. Nevertheless, an analysis of the efficiency of mixtures and a corresponding determination of the optimum mixture size (OMS) that minimizes the amount of material and instrumentation time required for an NMR screen has been lacking. A model for calculating OMS based on the application …

Alterations In Uterine And Placental Sodium Pump Abundance May Contribute To The Onset Of Mouse Labor, Carlos Jacob Vance

Theses and Dissertations

Objective: Reductions in sodium pump (SP) abundance can give rise to increases in contractile force in uterine and vascular smooth muscle as well as an increased secretion in secretory cells, including potentially those of the placenta. To determine whether the mouse might serve as a model for human pregnancy in terms of the SP and to determine whether changes in SP abundance anticipate or follow labor, we studied pregnant mice over the final trimester of their pregnancy.

Study Design: C57Bl6 dams (n=46) were bred and studied during their pregnancy. Animals (n=4) were sacrificed at specific gestational time points. Other mice …

Ion Transmission In The First Vacuum Stage Of An Inductively Coupled Plasma Mass Spectrometer, Jeffrey Harris Macedone

Theses and Dissertations

The inductively coupled plasma mass spectrometer (ICP-MS) is the instrument of choice for trace and ultra-trace elemental analysis. However, the ICP-MS suffers from matrix effects. Matrix effects occur when instrument response varies as the composition of the sample matrix is changed. Matrix effects, or non-spectroscopic interferences, limit the accuracy of routine analysis. Identification of the sources of matrix effects provide a basis for reducing or eliminating them. As inaccuracies in the ICP-MS are more severe than those in the ICP atomic emission spectrometer, the problem may be due, at least in part, to the vacuum interface used to couple the …

Semiclassical Nonadiabatic Dynamics With Quantum Trajectories, Vitaly A. Rassolov, Sophya V. Garashchuk

Faculty Publications

Dynamics based on quantum trajectories with approximate quantum potential is generalized to nonadiabatic systems and its semiclassical properties are discussed. The formulation uses the mixed polar-coordinate space representation of a wave function. The polar part describes the overall time evolution of the wave-function components semiclassically using the single-surface approximate quantum potential. The coordinate part represents a complex“population” amplitude, which in case of localized coupling can be solved for quantum mechanically in an efficient manner. In the high-energy regime this is accomplished by using a small basis determined by the coupling between surfaces. An illustration is given for a typical curve-crossing …

Clean, High-Yield Preparation Of S,S- And R,S- Amino Acid Isosteres, Aslam A. Malik, Todd E. Clement, Hasan Palandoken, James Robinson Iii, Joy A. Stringer

Chemistry and Biochemistry

The present invention provides compounds and methods that can be used to convert the intermediate halomethyl ketones (HMKs), e.g., chloromethyl ketones, to the corresponding S,S- and R,S-diastereomers. More particularly, the present invention provides: (1) reduction methods; (2) inversion methods; and (3) methods involving the epoxidation of alkenes. Using the various methods of the present invention, the R,S-epoxide and the intermediary compounds can be prepared reliably, in high yields and in high purity.

Reconstitution Of A Minimal Dna Replicase From Pseudomonas Aeruginosa And Stimulation By Non-Cognate Auxiliary Factors, Thale C. Jarvis, Amber A. Beaudry, James M. Bullard, Nebojsa Janjic, Charles S. Mchenry

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

DNA polymerase III holoenzyme is responsible for chromosomal replication in bacteria. The components and functions of Escherichia coli DNA polymerase III holoenzyme have been studied extensively. Here, we report the reconstitution of replicase activity by essential components of DNA polymerase holoenzyme from the pathogen Pseudomonas aeruginosa. We have expressed and purified the processivity factor (β), single-stranded DNA-binding protein, a complex containing the polymerase (α) and exonuclease (ϵ) subunits, and the essential components of the DnaX complex (τ₃δδ′). Efficient primer elongation requires the presence of αϵ, β, and τ₃δδ′. Pseudomonas aeruginosa αϵ can substitute completely for …

Electro-Magnetic-Optical Properties Of Yba2cu3o7 Crystal And 50 Nm Films On Sto-Bc 24 Deg Gb, Juana Acrivos, H. Sahibudeen, L. Nguyen, M. Navacerrada, J Kortight, P. Nachimuthu

Faculty Publications, Chemistry

Comparison of Is/I0 with TEY/I0, F/I0 and A, at the Cu L2,3 and Ba M4,5 edges indicates that YBa2Cu3O7 (YBCO) 50 nm films scatters the circular components of linearly polarized light in a different way. The YBCO, Ba L2,3 XAS shows indication of Faraday rotation near Tc. Hilbert analysis of data was done.

Magnetic Characterization Of Nanocrystalline Nickel Ferrite Films Processed By A Spin-Spraying Method, Gabriel Caruntu, I Dumitru, Bush Gg, Daniela Caruntu, Charles J. O'Connor

Chemistry Faculty Publications

Highly crystalline nickel ferrite films with different chemical compositions were processed via the spin-spraying method and their morphological, structural and magnetic properties were subsequently investigated. Regardless of the chemical composition, films with variable thicknesses are constructed by 200–400 nm spherical grains grown in the direction normal to the substrate surface. Magnetization measurements show that the spinel ferrite films present a hysteretic behaviour at room temperature with a randomly oriented in-plane easy axis and an anisotropy constant K1 ≈ −2.5 × 104 erg cm−3 Furthermore, the absence of an angular dependence of the coercivity for the in-plane measurement of …

Simulations Of Proton Order And Disorder In Ice Ih, Steven W. Rick

Chemistry Faculty Publications

Computer simulations of ice Ih with different proton orientations are presented. Simulations of proton disordered ice are carried out using a Monte Carlo method which samples over proton degree of freedom, allowing for the calculation of the dielectric constant and for the examination of the degree of proton disorder. Simulations are also presented for two proton ordered structures of ice Ih, the ferroelectric Cmc2₁ structure or ice XI and the antiferroelectric Pna2₁ structure. These simulations indicate that a transition to a proton ordered phase occurs at low temperatures (below 80 K). The …

Optimal Sampling Of A Chemical Hazard Area, Jennifer R. Plourde

Theses and Dissertations

This thesis proposes a methodology for optimally sampling a chemical hazard area subsequent to a chemical weapons attack. The objective is to identify the maximum number of areas that no longer require protective gear for safe operations. We model the area as an undirected graph and employ network analysis techniques to provide a methodological framework for identifying an optimal sampling sequence within a fixed time limit. We propose four models that characterize the secondary vapor concentrations: i) static and deterministic, ii) static and stochastic, iii) dynamic and deterministic, and iv) dynamic and stochastic. Comparisons of the static cases and their …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System: Quaterly Report January - March, 2005, Kenneth Czerwinski, Cynthia-May Gong, Amber Wright

Separations Campaign (TRP)

The speciation of hexavalent U and tetravalent Pu will be examined in the TBP-dodecane-nitric acid systems. This topic is chosen based on data needs for separation modeling identified by the AFCI. Emphasis will be placed on studying the influence of nitrate and acetohydroxamic acid on U and Pu speciation as well as conditions where a third phase forms in the organic phase. The organic phase will be 30% TBP in dodecane. Equal volumes of aqueous and organic phase will be used. The speciation of the actinides in the aqueous and organic phase will be determined by a number of different …

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System: Quarterly Report January - March, 2006, Amber Wright, Frederic Poineau, Kenneth Czerwinski

Separations Campaign (TRP)

The speciation of hexavalent U and tetravalent Pu will be examined in the Tributylphosphate (TBP)-dodecane-nitric acid systems. This topic is chosen based on data needs for separation modeling identified by the AFCI. Emphasis will be placed on studying the influence of nitrate and acetohydroxamic acid on U and Pu speciation as well as conditions where a third phase forms in the organic phase. The organic phase will be 30% TBP in dodecane. Equal volumes of aqueous and organic phase will be used. The speciation of the actinides in the aqueous and organic phase will be determined by a number of …

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Quarterly Report, January 2005 To March 2005, Earl Wolfram, Thomas Hartmann, Kenneth Czerwinski

Fuels Campaign (TRP)

This project will examine inert matrix fuels containing ZrO₂ and MgO as the inert matrix, with the relative amount of MgO varied from 30% to 70% in ZrO₂. Reactor physics calculations will be used to examine suitable quantities of burnable poisons from the candidate elements Gd, Er, or Hf with reactor grade Pu providing the fissile component, with up to 10% of ²³⁹Pu. Ceramics will be synthesized and characterized based on the reactor physics results. The solubility the fuel ceramics, in reactor conditions, reprocessing conditions, and repository conditions, will be investigated in a manner to provide …

Non-Adiabatic Energy Surfaces Of The B+H2 Systems, Lachlan T. Belcher

Theses and Dissertations

In order to solve the dynamics of a system, the kinetic energy operator of the Hamiltonian must be diagonalized. Diagonalization requires rotation of the system into a non-adiabatic representation. This rotation is a coupling angle determined by the derivative coupling terms. Derivative coupling terms are calculated using Columbus and Brooklyn, software packages. Separation of internal dynamics characterized by Jacobi coordinates, and external dynamics characterized by a set of Euler angles and the center of mass position, requires a transformation from Cartesian coordinates to Jacobi coordinates required for subsequent dynamical calculations. Previous attempts to solve for non-adiabatic energy surfaces in this …

An Investigation Into Palladium-Catalyzed Reduction Of Perchlorate In Water, Eric G. Barney

Theses and Dissertations

In this study, application of a catalytic reactor to facilitate chemical reduction of perchlorate was investigated. Palladium-coated pellets were used as the catalyst, and formic acid was used as the reductant. Reactor performance was evaluated under a variety of operating conditions (influent pH, reductant concentration, residence time). Very little perchlorate reduction was observed under any operating condition. At best, approximately 8% perchlorate reduction was observed. This small reduction efficiency is clearly not sufficient for environmental treatment applications. Perchlorate strongly adsorbed to the catalyst at low pH (3 - 3.3). At higher pH (4 - 10), little adsorption was observed. This …

Corrosion Behavior Of Mg2-XLaXNi And Mg2-XCeXNi Hydrogen Storage Alloy, Hai-Chang Zhang, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

The corrosion behavior of Mg-base hydrogen storage alloys has been investigated by potentiodynamic polarization and EIS. The results showed that the corrosion current density (i_corr) and the electrochemical polarized resistance of Mg_2-xCe_xNi alloys decreased with x increase, while i_corr of Mg_2-xLa_xNi alloys increased and the electrochemical polarized resistance of Mg_2-xLa_xNi alloys increased first, then decreased with x increase. SEM results showed that the surface of Mg_1.85Ce_0.15Ni alloy was relatively even while the surface of Mg_2-xLa_xNi alloy had …

Corrosion Resistance For Tio2 Thin Films Coated 316l Stainless Steel In The Nacl Solution, Guang-Xia Shen, Yi-Cong Chen, Chang-Jian Lin

Journal of Electrochemistry

The nano-TiO₂ thin films have been deposited on the 316L stainless steel by sol-gel and the dip-coating methods. Hydrothermal post-treatment leads to crack-free coatings. Meanwhile, the surface structure and properties are optimized. Surface morphology, structure and properties are characterized by XRD, and SEM technologies. The results have shown that the surface of coatings is porous, uniform and orderly, the particle diameters are in the range of 15~18 nm and the pores are about 4~8 nm and TiO₂ is anatase. The results of electrochemical measurements show that in the NaCl solution with pH ≥ 2 and concentration below 1mol/L, …

Calcium Zincate Prepared By Ball Mill Method, Sheng-Xian Li, Shuan-Bao Tian, Shao-Shan Zhu

Journal of Electrochemistry

Calcium zincate was prepared by ball milling method and the factors that influence its synthesis were investigated. The composition of the compound was Ca(OH)₂·2Zn(OH)_2^·2H₂O, which was verified by XRD and TG-DTA methods. The results of powder microelectrode and in simulated batteries showed that the material had excellent cyclic performance.

Influence Of Rare Earth Oxide On The Performance Of Secondary Zinc Electrodes, Xian-Ling Meng, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

Influence of La(OH)₃ or Ce(OH)₃ in secondary zinc electrode was investigated by the cyclic voltammetry, potentiodynamic polarizationand potentiostatic polarization tests and influence of La₂O₃ or CeO₂ in the charge/discharge performance of Zn/Ni battery was studied by galvanostatic charge/discharge experiment. The results showed that the film of rare earth hydroxide prevented the zincate species from transferring toward solution, enhanced hydrogen overpotential and decreased thecorrosion current density (i_corr), and therefore inhibited zinc corrosion. The potentiostatic polarization results at100mV overpotential showed that La(OH)₃ or Ce(OH)₃ oated on the zinc electrode effectively suppressed the …