Chemistry Commons^™

Self Assemblying Kinetics Of Sodium Steareate At Castor Oil/Water Interface, Yong-Chun Zhu, Li-Na Tang, Hong-Guo Ji

Journal of Electrochemistry

The self assembly membrane(SAM)formation kinetics of sodium stearate at castor oil/water interface was studied by cyclic voltammetrry.At caster oil coated graphite-epoxy solid electrode surface,the SAM grows according to the Gaussian growth function with a rate constant of km=0.0006292(0.0000294)s^-1,and maximum particle size at t0=3127s.The SAM of sodium stearate controls the growth and particle size of the deposited copper nano particles well,and forms a composite membrane of the SAM and copper nano particle.The growth mechanism of copper particle at oiled electrode or SAM modified oiled electrode is spherical growth,while it is the semi-spherical growth at bared graphite-epoxy solid phase electrode.Compared …

Determination Of Tetracyclines Based On The Flow-Through Electrochemical Detection Cell With Nickel Electrode, Dan-Mei Pan, Rong-Zong Hu, Dong-Ping Wei, Hao-Dong Ding

Journal of Electrochemistry

The electrochemical responses to tetracycline at the nickel electrode in alkaline solution were compared with that of gold and glassy carbon electrode by voltammetry.The electrocatalytic oxidation characteristics of tetracycline at nickel electrode were discussed.Subsequently a flow-through amperometric detection cell with nickel as the working electrode was designed to detect tetracycline,oxytetracycline,and doxycycline.Standard calibration graphs for the tetracyclines yielded linear ranges of 0.1~15 mg/L.Detection limits(S/N=3)of 35,45 and 43 μg/L were obtained for tetracycline,oxytetracycline and doxycycline,respectively.The system was applied for the determination of the three antibiotics in single-component drug formulations.

Study On The Electrogeneration And Properties Of Superoxide Ion In Aprotic Media By Using Carbon Nanotubes Powder Microelectrode, Ying-Liang Wei, Chen Shao, Hui Feng

Journal of Electrochemistry

Multi-wall carbon nanotubes are filled in the cavity at the tip of a microelectrode to form a carbon nanotubes powder microelectrode(CNTs-PME).The CNTs-PME is used to study the electrochemical reduction of oxygen in aprotic media.It is a nearly reversible redox process of the O₂/O₂^- couple at the CNTs-PME in the dimethyl sulfoxide(DMSO)solution.The heterogeneous electron transfer rate constant(ks)can be measured by steady-state voltammogram and the result is 9.8 10^-3cm /s.As a weak oxidant,the reaction of O₂^- with epinephrine was studied by cyclic voltammetry.Additionally,the reaction of O₂^- with benzoic acid was also discussed …

Hydriding And Dehydriding Properties Of Mg/Mg(1.8)La(0.2)Ni Nanocomposites, Hong-Liang Sun, Yan-Yan Zhang, Hai-Chang Zhang, Hua-Bin Yang, Zuo-Xiang Zhou

Journal of Electrochemistry

Mg_{-x %}Mg_1.8La_0.2Ni(x=10,20 and 30)nanocomposites have been synthesized by high-energy ball milling method.Results of the X-ray diffraction(XRD),transmission electron microscopy(TEM)and selected area electron diffraction(SAED)tests were showed that each composite had a nanocrystalline/amorphous structure,which was beneficial for the improvement of the hydriding and dehydriding properties of Mg.The hydrogen absorption temperature decreased and the hydrogen sorption kinetics were improved.Under the conditions of 423 K and the hydrogen pressure of 2.5MPa,each composite could reach the maximum hydriding capacity within 50 s.

Square Wave Stripping Voltammetric Behaviors Of Actinomycin D On Glod Electrode And Its Application, Qing-Tao Zhu, Fang Liao, Xiao-Ying He

Journal of Electrochemistry

The electrochemical behaviors of Actinomycin D(ACTD)at glod electrode were investigated by square wave stripping voltammeter in the KH₂PO₄-Na₂HPO₄ buffer solution(pH=5.90).The sensitive oxidation peak of ACTD was observed and the potential peak for ACTD is-0.17 V(vs.SCE).The Experimental parameters,such as pH value,amplitude,accumulation potential and time were optimized,and a direct electroanalytical method for determining ACTD was developed.The peak currents were proportional to the concentration of ACTD in the range of 0.1μmol·L^-1～10.0μmol·L^-1,and the linear regression coefficient equaled 0.9991.The detection limit for ACTD was 1.0×10^-8mol·L^-1.

Voltammetric Behavior And Electrocatalytic Properties Of Hemoglobin At Glassy Carbon Electrode Modified With Lauric Acid, Xin-Rui Miao, Xu-Hong Zhang, Ying Xie

Journal of Electrochemistry

The electrochemical behavior of hemoglobin at glassy carbon(GC)electrode modified with Lauric Acid was studied.In the potential of +0.6～-0.7 V(vs.Ag/AgCl),an irreversible cathodic peak was observed at-0.3 V at the scan rate of 20 mV·s^-1.In the medium of 0.02 mol·L^-1 KH₂PO₄-Na₂HPO₄(pH 7.0),ip increased with the increasing concentration of Hb and the value of pH.The peak currents were proportional to the concentrations of hemoglobin in the range of 1.00×10^-8～5.00×10^-9 mol·L^-1 and 1.92×10^-6～2.06×10^-7 mol·L^-1.The data was analyzed in details by simulating in order to …

Modification Of Electrolytic Manganese Dioxide, Shu-Rong Ding, Xin-Hai Li, Zhi-Xing Wang, Hua-Jun Guo

Journal of Electrochemistry

The EMD samples coated with CMD-Bi compound were prepared by liquid-phase surface treatment method.XRD and SEM research indicated that the modified manganese dioxide, i.e, EMD/CMD-Bi, could keep γ-MnO₂ crystal structure of EMD and had more pores on its surface with an obvious floccule layer.Electrochemical test indicated that the second electron reduction peak current increased by 1.5 times and the discharge capacity increased by 40.8% and 78.3% respectively than that of pure EMD electrode under the condition of-0.8 V(vs.Hg/HgO) cut-off voltage at 30.8 mA/g and 102.7 mA/g current density.

Electrochemical Performance Of Li(1-X)MXFepo4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai

Journal of Electrochemistry

Olivine Li_1-xM_xFePO₄(M=Cr³⁺, Mg²⁺, Mn²⁺, Ni²⁺) were synthesized by a polyacrylates-pyrolysis route. The structural and electrochemical properties of the as-synthesized cathode materials were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical charge/discharge cycling. The results indicate that the metallic ions doped at low concentration do not affect the crystalline structure of the material, but considerably improve the rate capability and cycle performance of LiFePO₄ at high rate.

Study On The Electrochemical Extraction Of Oxygen And Influence Factors Of Oxygen Purity, Xiao-Ke Zhi, Guang-Chuan Liang, Xiu-Qin Ou, Shu-Guang Liu, Bin Han

Journal of Electrochemistry

A method for the electrochemical extraction of oxygen is prasented.The concentration of HO₂^-ions and the purity of oxygen were measured by KMnO₄ standard method,and by cuprammonium absorb method respectively.Effect of the membrane and the spacing between cathode and anode on the purity of oxygen were also tested.The experiment results were showed that the system could work continuously above 500h and the purity of oxygen was above 99.8% when using proper membrane at 80 mA·cm^-2 current density,Electrochemical reaction included 4e reacting course and 2e reacting course,the ratio of 2e reaction is about 38%~44% of the whole …

Hygroscopic Behavior Of Nacl-Bearing Natural Aerosol Particles Using Environmental Transmission Electron Microscopy, Matthew E. Wise, Trudi A. Semeniuk, Roelof Bruintjes, Scot T. Martin, Lynn M. Russell, Peter R. Buseck

CUP Faculty Research

We used conventional and environmental transmission electron microscopes to determine morphology, composition, and water uptake of individual natural inorganic aerosol particles collected from industrial pollution plumes and from clean and polluted marine environments. Five particle types are described in detail. They range from relatively insoluble mineral grains to internally mixed particles containing NaCl with other soluble or relatively insoluble material. We studied the hygroscopic behavior of these particles from 0 to 100% relative humidity (RH). Relatively insoluble materials do not take up water over the experimental RH range. Single crystals of NaCl from both natural and laboratory sources have a …

Functionalization Of Resorcinarenes And Study Of Antimicrobial Activity, Kirankirti Muppalla

USF Tampa Graduate Theses and Dissertations

Cavitands are very important class of compounds in supramolecular chemistry. These molecules contain rigid enforced cavity,and have attracted considerable attention in supramolecular chemistry as building blocks for the construction of carcerands, hemicarcerands, and other host guests complexes. Nearly 40 years ago, Niederl and Vogel laid foundation for the study of such type of condensation reactions. In our laboratory we are involved in synthesis of resorcinarenes with readily available substrates such as resorcinol and aldehydes to form a cyclic tetramer.

Herein, I present detailed studies about the functionalization of the synthesized tetramers and their antimicrobial activity. Octahydroxy resorcinarenes were synthesized and …

Interview With Emil Slowinski, Dewitt Wallace Professor Of Chemistry, Emil Slowinski

Chemistry Department Oral Histories

No abstract provided.

Human Frataxin: Iron And Ferrochelatase Binding Surface, Krisztina Z. Bencze, Taejin Yoon, CéSar MilláN-Pacheco, Patrick B. Bradley, Nina Pastor, J. A. Cowan, Timothy L. Stemmler

Biochemistry and Molecular Biology Faculty Publications

The coordinated iron structure and ferrochelatase binding surface of human frataxin have been characterized to provide insight into the protein’s ability to serve as the iron chaperone during heme biosynthesis.

1,4-Di-9-Anthrylbutane, Mustafa Arslan, Erol Asker, John Masnovi, Ronald J. Baker

Chemistry Faculty Publications

In the title compound, C₃₂H₂₆, the molecule has an inversion centre at the mid-point of the central C—C bond. Weak intermolecular C—H...π interactions help to stabilize the crystal structure.

A Tandem Enol Silane Formation-Mukaiyama Aldol Reaction Mediated By Tmsotf, C. Wade Downey, Miles W. Johnson

Chemistry Faculty Publications

A slight excess of silyl trifluoromethanesulfonate mediates a tandem enol silane formation-Mukaiyama aldol reaction in the presence of Hunig’s base. Preformation of the enol silane is unnecessary for efficient reactions, which proceed in 75–97% yield for the addition of aryl methyl ketones and acetate esters to non-enolizable aldehydes. Mechanistic data suggests that free amine is crucial for full conversion.

Asymmetric Dihydroxylation And Aziridination Of Allenes And Related Chemistry, Renmao Liu

Theses and Dissertations

A novel method for asymmetric synthesis of α-hydroxy ketone with excellent regio- and stereoselectivity has been established by the systematic investigation of asymmetric dihydroxylation of allenes. The efficiency of kinetic resolution of racemic allenes was also investigated by using the AD reaction on both 1,3-disubstituted and trisubstituted allenes. Steric effects, electronic effects and allene substitution are also discussed. Aziridines were formed by copper-catalyzed intramolecular nitrene addition to alkenes. The carbamate group was used as the tether between the alkene and the nitrene. Subsequent nucleophilic attack of the aziridine was accomplished using RSH, R2NH, N3-,or ROH as the nucleophile. This addition …

Microwave Absorption Of Patterned Arrays Of Nanosized Magnetic Stripes With Different Aspect Ratios, Leszek M. Malkinski, Minghui Yu, Andriy Vovk, Donald J. Scherer Ii, Leonard Spinu, Weilie Zhou, Scott L. Whittenburg, Zachary Davis, Jin-Seung Jung

Chemistry and Biochemistry Faculty Publications

Arrays consisting of nanosized stripes of Permalloy with different length-to-width ratios have been fabricated using electron beam nanolithography, magnetron sputtering, and lift-off process. These stripes have a thickness of , a width of , and different lengths ranging from . The stripes are separated by a distance of . Magnetization hysteresis loops were measured using a superconducting quantum interference device susceptometer. Microwave absorption at was determined by means of ferromagnetic resonance technique. The dependence of the resonant field on the angle between the nanostructure and the in-plane dc magnetic field indicates the presence of uniaxial magnetic anisotropy associated with the …

Stability Testing Of Mint Oils Through Gas Chromatography Analysis, Sarah Wolf

Honors Theses

In this experiment, the stability of mint oil was measured through gas chromatography analysis. Eight different oils were tested. Levels of key components of mint oil, including menthol and menthone for peppermint oil, and carvone and limonene for spearmint oil, was compared over time. Several packaging materials were immersed in oils in order to determine their effects, if any, on the composition of the oils. Additionally, oil was subjected to either 25 degree or 40 degree Celsius temperatures to determine if temperature affected the oil composition.

Towards Early State Disease Detection In Microdevices: Fabrication And Testing Of Micro Total Analysis Systems For Bioanalytical Applications, Tao Pan

Theses and Dissertations

The past few years have seen a rapid expansion in interest in the characterization of the entire complement of proteins, or proteome. Micro total analysis systems (μTAS) are an emerging promising method, offering rapid, sensitive and low sample consumption separations. I have demonstrated microchip capillary electrophoresis (CE) devices made of CaF2. New methods have been developed for micromachining enclosed capillaries in CaF2. CE analysis of fluorescently labeled amino acids was used to illustrate bioanalytical applications of these microdevices. Initial on-chip infrared spectroscopy results for qualitative analyte identification were achieved in microfluidic CaF2 channels. I have also shown the evaluation of …

Sem Analysis Of Glue Behavior When Bonding Glass Structures With Complex Geometries, Yuri Sikorski, Robert Cunningham, Herman Orgeron, Chris Schenck, Ali Zand

Chemistry & Biochemistry Presentations And Conference Materials

Bonding of glass has been studied for many years and is a mature technology today. However, the recent advances in bio-photonics and micro-fluidics, such as lab-on-a-chip devices, accentuate a need to provide reliable adhesion and sealing of components with extremely complex surface geometries. In many cases it is necessary to prevent the adhesives from leaking into microscopic channels, capillaries and holes. We present the Scanning Electron Microscopy study of adhesion of glass samples with complex surface features. Variety of adhesion conditions and procedures were tried and studied. The results demonstrate the possibility of controlled reliable adhesion and sealing without filling/obstructing …

Synthesis, Reactions, And Applications Of Bis-Ortho-Diynyl Arene (Boda) Monomers, Polymers, And Derivatives, Mark Perpall

All Dissertations

Bis-ortho-diynyl arenes (BODA) monomers contain two arenediyne functional groups with variable functionality at both the linker group, X, and the alkyne terminal group, R. These arenediyne moieties undergo thermal Bergman reactions to cycloaromatize to naphthyl diradical species. The inclusion of two of these arenediyne functionalities allows the polymer to grow without losing processability and solubility as most aromatic polymers do. The second functionality acts as a solubilizing group until all functionalities are consumed in the fully cured network polymer.
When heated above 800 °C, BODA polymer converts to a high-yield glassy carbon material. This work has been extended …

Stirling's Approximation, Carl W. David

Chemistry Education Materials

Stirling's approximation is discussed.

Exploratory Synthesis And Characterization Of New Mixed-Framework Chalcohalides And Oxyhalide And Its Potential Applications For Diluted Magnetic Semiconductor, Lei Wang

All Dissertations

Due to the excellent diverse properties and performance, solid-state material with low-dimensional crystal structure has always been interested by solid-state scientists. Besides the interesting properties, the low-dimensional-structured materials are used as the platform for further research and application of semiconductor and optical devices, as well as theoretic studies. My dissertation research mainly focuses on two aspects: discovery of solids with low-dimensional crystal structure; fabrication and investigation of new materials using the discovered materials as the platform.
The idea of mixed-anion-framework has been used in synthesis of novel low-dimensional-structured solid-state materials. The stereo-active Sb³⁺/Bi³⁺ chalcogenides building units and …

Carbon Dioxide Capture: Using Activated Carbon From Chicken Waste, Yan Zhang

Masters Theses & Specialist Projects

Carbon Dioxide (CO2) emission from hydrocarbon fuel combustion is becoming a serious concern because it is the main contributor to greenhouse gas which causes global warming. Activated carbon sorbents have been used widely in various gas-phase and/or liquid-phase separation. Currently activated carbon (AC) is being investigated and developed for CO2 capture. Chicken waste, which is produced in large quantity in U.S., is currently disposed as waste. However, it may have a large benefit to turn chicken waste into useful activated carbon. In this research, a series of activated carbon have been generated from chicken waste and coal in the lab …

Electronic Anisotropy Between Open Shell Atoms In First And Second Order Perturbation Theory, Gerrit C. Groenenboom, Xi Chu, R. Krems

Chemistry and Biochemistry Faculty Publications

The interaction between two atoms in states with nonzero electronic orbital angular momenta is anisotropic and can be represented by a spherical tensor expansion. The authors derive expressions for the first order (electrostatic) and second order (dispersion and induction) anisotropic interaction coefficients in terms of the multipole moments and dynamic polarizabilities of the atoms and show that a complete description of the second order interaction requires odd rank or "out-of-phase" polarizabilities. The authors relate the tensorial expansion coefficients to the adiabatic Born-Oppenheimer potentials of the molecule and show that there are linear, and in some cases nonlinear, constraints on the …

Watching Ultrafast Barrierless Excited-State Isomerization Of Pseudocyanine In Real Time, Benjamin Dietzek, Arkady Yartsev, Alexander N. Tarnovsky

Chemistry Faculty Publications

The photoinduced excited-state processes in 1,1'-diethyl-2,2'-cyanine iodine are investigated using femtosecond time-resolved pump-probe spectroscopy. Using a broad range of probe wavelengths, the relaxation of the initially prepared excited-state wavepacket can be followed down to the sink region. The data directly visualize the directed downhill motion along the torsional reaction coordinate and suggest a barrierless excited-state isomerization in the short chain cyanine dye. Additionally, ultrafast ground-state hole and excited-state hole replica broadening is observed. While the narrow excited-state wavepacket broadens during pump-probe overlap, the ground-state hole burning dynamics takes place on a significantly longer time-scale. The experiment reported can be considered …

Department Of Chemistry News For Alumni And Friends, May 2007, Illinois State University, Department Of Chemistry

Chem Letter

Newsletter of the Illinois State University Department of Chemistry

Direct Analysis Of Solid Corrosion Products By Laser Ablation Icp-Ms: Method Development And The Interaction Of Aqueous Uranium, Gadolinium And Neodymium With Iron Shot And Iron (Iii) Oxide, James Cizdziel, Klaus J. Stetzenbach, Amy J. Smiecinski

Publications (YM)

The purpose of this report is to summarize the work and present conclusions of Project Activity Task ORD-RF-03 conducted under cooperative agreement number DE-FC28-04RW12237 between the U.S. Department of Energy and the Nevada System of Higher Education (NSHE). The work was conducted in the Harry Reid Center for Environmental Studies of the University of Nevada Las Vegas from October 1, 2004 to September 30, 2006. The purpose of the study was to develop a method using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for the direct analysis of iron corrosion products, to evaluate its capabilities, advantages, and limitations, and …

Investigations Of The Mechanism Of Dna Cleavage Using Ruthenium Polypyridyl Complexes, Fiona Ongeri

Chemistry & Biochemistry Theses - Archive

We have synthesized a ruthenium complex, [(phen)2Ru(tatpp)Ru(phen)2]4+ (P4+), which has been shown to undergo various redox and protonation steps to form different species that can be monitored by UV-Vis spectroscopy. In Chapter 2, the photochemistry of P4+ in the presence and absence of DNA was studied. It was hypothesized that the lifetime (t1/2) of the excited state of P4+, P*, would be extended in the presence of DNA. However, studies conducted showed that the lifetime of P* was diminished in the presence of DNA as compared to P4+ alone. Experiments have also shown that P4+ is capable of damaging DNA …

Trans-Excision-Splicing Ribozyme And Methods Of Use, Stephen M. Testa, Michael A. Bell

Chemistry Faculty Patents

A group I intron-derived ribozyme which binds RNA in trans, excises an internal segment from within the RNA, and splices the remaining 5′ and 3′ ends of the RNA back together (the trans-excision-splicing reaction) is disclosed. The excised segment can be as long as 28 nucleotides, or more, and as little as one nucleotide. The ribozymes of the invention are easily modified to alter their sequence specificity. Such ribozymes represent a new and potentially powerful class of generally adaptable genetic therapeutics.