Chemistry Commons^™

Fabrication Of Superhydrophilic Aluminum Oxide Through Single-Step Anodic Oxidation, Qin Zhang, Qi-Ming Yin, Jia-Ming Ye, Yuan-Rong Zhu

Journal of Electrochemistry

Hydrophilic aluminum oxide is popularly used for heat exchanger of air-condition.Herein,we developed a simple method to prepare superhydrophilic aluminum oxide on the surface of aluminum through single-step electrochemical oxidization.The morphologies and water contact angles on surfaces of alumina fabricated under different electrochemical conditions were investgated.Superhydrophilic surfaces fabricated by this method have good stability and high mechanical strength with water contact angle almost 0°.Coated with low surface energy materials,superhydrophilc alumina will be converted to superhydrophobic.

Voltammetric Determination Of L-Cysteine At Bipyrine Bridged Copper(Ⅱ) Complex Modified Glassy Carbon Electrode, Ming-Yan Wang, Fan Yang, Sheng-Yu Zhang, Xing-You Xu, Xu-Jie Yang

Journal of Electrochemistry

A modified electrode has been constructed by depositing a novel copper(Ⅱ) complex 2biPy(ClO₄)₄ on the glassy carbon electrode through the method of cyclic voltammetry(CV).It was found that the modified electrode exhibited high electrocatalytic activity toward L-Cysteine oxidation with good reproducibility and high sensitivity.The peak current of semi-derivative linear scan was proportional to the concentration of L-cys in the range of 1×10^-6～3×10^-4 mol·L^-1.The detection limit was 5×10^-7 mol·L^-1.

Studies Of Surface Diffusion In Pemfc Electrodes, Jiang-Shui Luo, Jian Chen, Bao-Lian Yi, Chuan-Sin Cha, Hua-Min Zhang

Journal of Electrochemistry

A PEMFC electrode consisting of dual-layer catalyst layer(CL) was fabricated in this work. The outer CL was Nafion-free,while the inner CL was Nafion-bonded. The effects of Pt/C catalyst in the outer CL that did not contact with Nafion on the current generation in PEMFC electrodes were investigated. Cyclic voltammetric studies indicated that the Pt/C catalyst in the outer CL without direct contact with Nafion was still electrochemically active in taking part in the adsorption/desorption of hydrogen and the electrochemical oxidation/reduction of the oxygen-containing species occurring at the interface of "Pt/Nafion" in the inner CL. The polarization curves showed that the …

Preparation And Electrocatalystic Performance Of Ir/C Catalyst For Ammonia Oxidation, Qing-Mei Kong, Yi-Ping Han, Ling-Juan Deng, Tian-Hong Lu, Ya-Wen Tang

Journal of Electrochemistry

The Ir/C catalyst with 30%(by mass) Ir was prepared in the CH₃CH₂OH and H₂O binary system.The X-ray diffraction(XRD) data showed that the average sizes of the Ir particles in the Ir/C catalyst was about 2.2 nm.The results of the electrochemical measurements indicated that the electrocatalytic activity of the Ir/C catalyst for the ammonia oxidation in the neutral NaClO₄ solution was similar to the Ir catalyst,while electrocatalytic stability was much better than that of the Ir catalyst.Furthermore,the peak current density of the ammonia oxidation at the Ir/C catalyst electrode showed a good linear relationship …

Direct Electrochemistry Of Chloroperoxidase At Gc Electrode Modified With Swnts, Hong-Xia Zhang, Xia-Qin Wu, Wen-Jing Hou, Wen Xie, Zhong-Qing Lu, Rong Wang, He-Xing Li

Journal of Electrochemistry

The chloroperoxidase(CPO) was immobilized onto the surface of SWNTs modified electrodes.The electrochemical behaviors of modified electrode have been investigated by cyclic voltammetry.The appearance of a pair of well-defined redox peaks in the CV curve indicated that SWNTs can promote the electron transfer reaction of CPO.The results of cyclic voltammetry in PBS of different pH,from 3~9,showed that the reaction of CPO on the modified electrode was with equal numbers of electron and protein.This readily prepared SWNTs modified electrode showed excellent stability and good catalysis to O₂.

Electrochemical Properties Of Lamg(11)Zr+Ni Composite, Xin-Chun Yan, Zi-Li Liu, Xin-Bo Liu

Journal of Electrochemistry

Using the LaMg11Zr as the initial alloy,the LaMg₁₁Zr+Ni composite was prepared by mechanical alloying,and the effect of ball-milling time on the amorphous structure of alloy powers was characterized by X-ray diffraction(XRD).The amorphous(LaMg₁₁Zr+Ni) alloy can be obtained after 20 h ball-milling,and has the best electrochemical capacity,electrochemical cycle stability.

Application Of Self-Assembly Technique In The Process Of Metallized Fabric, Yue-Hui Ma, Wei Wang, Dan Yu, Jin-Xin He

Journal of Electrochemistry

After the pretreatment of nylon fabric by functional chitosan,the self-assembly technique was used in the process of activation before electroless plating to produce the CS-Pd membrane.The nanosized palladium particles with nanoscal have large relative surface and high catalyzed activity.Electromagnetic wave shielding fabric was prepared by electroless plating of Ni-P alloy with the activated fabric.The optimal process condition of CS finishing was given with the orthogonal and single factor experiments.The variation of fabric surface structure was characterized by SPM,SEM.Based on the Schelkunoff theory.The electromagnetic shielding effectiveness comes above 30 dB,which corresponds to shielding 96.0 percent of the electromagnetic wave or more.

Behavior Of Copper Electrodeposition In Copper Electroplating Solution With Different Peg Molecular Weight, Lie Yin, Zeng-Lin Wang

Journal of Electrochemistry

The effect of the polyethylene glycol(PEG) molecular weight(MW) upon via-hole filling with diameter of 50 μm and aspect ratio of 1 in the acid copper plating solution was studied.The cathodic polarization in copper electroplating bath with PEG of different molecule weights was investigated by linear sweep voltammetry.The surface roughness,crystallography,and the resistivity of copper films were characterized by X-ray diffraction(XRD),atomic force microscopy(AFM) and the four-point probe measurements.The results showed that the polarization on the cathode and the hole-filling capability of electroplating copper bath were increased evidently with an increase of PEG molecular weight from 600 to 8000.When the PEG MW was …

Alkoxyamine Polymers: Versatile Materials For Surface Ligation Applications, Lindsey Hines, Jessica Moore, David Dahl, Belinda Lady, Johnathan Brantley, Hasan Palandoken

Chemistry and Biochemistry

Immobilization of biomolecules (i.e., proteins, carbohydrates), on polymeric surfaces has been an area of intense research. The resultant bioconjugates often display increased stability, bioavailability and activity. Our research program seeks to explore the utility of the alkoxyamine (RONH2) functional group in new materials as versatile ligating sites for the immobilization of various compounds.

The ease with which alkoxyamines (RONH2) condense with aldehydes or ketones has prompted their widespread use in labelling liposome, bacterial and mammalian cell surfaces as well as chemoselectively ligating small molecule ‘recognition elements' onto polyfunctional substrates. These condensation reactions proceed in aqueous media to afford the robust …

Cariporide Prodrugs: Targeting Brain Cancer Cells Through Sodium-Proton Exchange Inhibition, Jacob Vervynckt, Johnathan Brantley, Jessica Moore, Mark Graves Ii, William Harley, Fredric A. Gorin, Hasan Palandoken

Chemistry and Biochemistry

More than 200,000 people in the United States are diagnosed with a primary or metastatic brain tumor annually. The life expectancy for these individuals is approximately 9-12 months from the time of diagnosis. This poor prognosis is due to the ineffectiveness of existing therapies (i.e., chemotherapy and radiotherapy) against brain cancer, where the primary problem is the inability to differentiate cancer cells from healthy brain cells.

Relative to healthy brain tissue, the heightened metabolism of cancer cells increases their reliance on the ion transport proteins NHE (sodium-proton exchanger) and NCX (sodium-calcium exchanger). Inhibition of these proteins disrupts the intricate pH …

Synthesis And First X-Ray Structures Of Cobalt(Ii) And Cobalt(Iii) Complexes Bearing 2,4-Dioxo-Alkanoic Acid Dialkylamide Ligands, Brian Pagenkopf, Jian Wang, Nicholas A. Morra, Hongda Zhao, Vincent Lynch, Robert Mcdonald, John F. Reichwein

Chemistry Publications

The aerobic oxidation of 5-hydroxy pentenes to trans-tetrahydrofurans (THFs), the Mukaiyama oxidation, has in recent years emerged as a powerful tool in synthetic chemistry. In this report we describe the first crystal structures of 2,4-dioxo-alkanoic acid dialkylamide complexes for both Co(II) and Co(III) salts. The Co(II) structures show an unprecedented arrangement of atoms, with a central Co(II)(H₂O)₆ flanked by two Co(II) atoms each coordinated with three anionic chelating ligands. The dimeric Co(III) structures show two anionic chelating ligands and bridging hydroxyl groups.

Relaxations In Ba2bisbo6 Double Complex Perovskite Ceramics, Manoel Carvalho Castro Jr., Carlos William De Araujo Paschoal, Frank C. Snyder, Michael W. Lufaso

Chemistry Faculty Research and Scholarship

The electric properties of the complex double perovskite Ba2BiSbO6 have been investigated using impedance spectroscopy in the frequency range from 1 Hz up to 1 MHz and in the temperature range from room temperature up to 560 K. There are two contributions to the electrical properties due to the grain and grain boundary. The oxygen vacancies play an important role in the conductivity and strongly increase the dielectric constant at high temperatures. The analysis of the frequency dependence of the conductivity clearly shows the structural phase transition of this compound near 515 K.

Removal Of Benzaldehyde From Methanol Using Alkoxyamine Functionalized Silica Gel, Dino Sulejmanovic, Carrie Jo Pruitt, Eric Conte, Hasan Palandoken, Shing-Yi Suen

Chemistry and Biochemistry

Alkoxyamines (RONH₂) react readily with aldehydes and ketones to form stable oxime ethers, and, thus are expected to be excellent scavengers of these compounds. We installed alkoxyamines on silica gel surface to remove benzaldehyde from methanol. Silica gel was immersed in H₂O₂/H₂SO₄ solution to activate the surface. Activated silica gel was then reacted with 3-chloropropyltrichlorosilane. Displacement of the chloride with N-hydroxyphthalimide and subsequent treatment with hydrazine provided alkoxyamines on the surface of silica gel. The resulting silica gel surface with alkoxyamine functional groups was immersed in a 100 ppm benzaldehyde solution …

Probing Phenylalanine/Adenine Π-Stacking Interactions In Protein Complexes With Explicitly Correlated And Ccsd(T) Computations, Kari L. Copeland, Julie A. Anderson, Adam R. Farley, James R. Cox, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

To examine the effects of π-stacking interactions between aromatic amino acid side chains and adenine bearing ligands in crystalline protein structures, 26 toluene/(N9-methyl) adenine model configurations have been constructed from protein/ligand crystal structures. Full geometry optimizations with the MP2 method cause the 26 crystal structures to collapse to six unique structures. The complete basis set (CBS) limit of the CCSD(T) interaction energies has been determined for all 32 structures by combining explicitly correlated MP2-R12 computations with a correction for higher-order correlation effects from CCSD(T) calculations. The CCSD(T) CBS limit interaction energies of the 26 crystal structures range from -3.19 to …

The Effects Of A Networked Data Acquisition System On Student Learning In General Chemistry Laboratories, Stuart C. Burris, Les L. Pesterfield, Darwin Dahl, Hasan Palandoken, Jacqueline Pope-Tarrence

Chemistry and Biochemistry

We have recently incorporated a networked data acquisition and analysis system into in our second semester general chemistry laboratories. Our investigation team has conducted a study to evaluate the effects of the networked data acquisition system on student performance on a Beer's Law laboratory. We focused on two specific phenomena: the effect of the networked data acquisition system on 1) student learning of specific content material and 2) student comfort level with laboratory work and data analysis. The study involved a networked data acquisition group (employing a UV-Vis spectrometer and colorimeters) and a control group (employing traditional, single wavelength spectrometers). …

Photocycloaddition Of Allenes, Crystal Ward

Theses and Dissertations

For the past ten years the Fleming research group has been involved in the research of allene compounds. We have explored the synthesis of allenes as well as several reactions involving allenes, such as oxidation and nitrene addition. Recently, we have explored the synthesis and photochemistry of allenic alcohols tethered to silicon. There are literature examples using allenes in synthesis, but very few examples exist using allenes in photochemical cycloaddition reactions. We have found that a diisopropylallenyloxy(cinnamyloxy)silane derivative undergoes [2+2] photochemical cycloaddition to produce a cyclobutylsilane product when irradiated for 60-75 minutes.

Patent: Cell-Permeable Miniature Proteins, Alanna S. Schepartz, Douglas S. Daniels, Betsy Smith

Chemistry Faculty Publications

Abstract: The present invention generally relates to miniature proteins, including miniature proteins that are permeable to cells. Certain aspects of the invention are generally related to miniature proteins, such as avian pancreatic polypeptide (aPP), modified such that the miniature proteins are permeable to cells. For instance, a portion of the aPP, such as the alpha helix region and/or the type II polyproline helix region, may be modified to render the region substantially cationic. As an example, one or more residues may be substituted with cationic amino acid residues such as arginine. The miniature proteins may also have additional functions, such …

Multicolor Conjugated Polymer Dots For Biological Fluorescence Imaging, Changfeng Wu, Barbara Bull, Craig Szymanski, Kenneth Christensen, Jason Mcneill

Publications

Highly fluorescent conjugated polymer dots were developed for demanding applications such as fluorescence imaging in live cells. These nanoparticles exhibit small particle diameters, extraordinary fluorescence brightness, and excellent photostability. Single particle fluorescence imaging and kinetic studies indicate much higher emission rates (∼10⁸ s⁻¹) and little or no blinking of the nanoparticles as compared to typical results for single dye molecules and quantum dots. Analysis of single particle photobleaching trajectories reveals excellent photostability—as many as 10⁹ or more photons emitted per nanoparticle prior to irreversible photobleaching. The superior figures of merit of these new fluorescent probes, together …

Localised Galvanic Corrosion Processes In Thermal Spray Coated/Cast Aluminium Alloy Systems, David Culliton, Tony Betts, David Kennedy

Conference Papers

Cast Aluminium Alloys, because of the propensity of aluminium to react with impurities and alloying elements, are prone to developing IM impurities during the solidification process. These IM phases can act, in some fluids, as initiation sites for localised corrosion processes, resulting in degradation phenomena, such as pitting. Whilst Thermal Spray coatings can improve the wear resistance of Cast Aluminium Alloys, their corrosion performance may be hampered by the presence of through porosity within the coating.

The present work details some preliminary studies of the localised corrosion processes occurring at the interface area between a Thermal Spray coating and a …

Three-Dimensional Modeling Of The Plasma Arc In Arc Welding, Gu Xu, J. Hu, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Most previous three-dimensional modeling on gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) focuses on the weld pool dynamics and assumes the two-dimensional axisymmetric Gaussian distributions for plasma arc pressure and heat flux. In this article, a three-dimensional plasma arc model is developed, and the distributions of velocity, pressure, temperature, current density, and magnetic field of the plasma arc are calculated by solving the conservation equations of mass, momentum, and energy, as well as part of the Maxwell's equations. This three-dimensional model can be used to study the nonaxisymmetric plasma arc caused by external perturbations such as …

2d Regional Correlation Analysis Of Single-Molecule Time Trajectories, Xuefei Wang, H. Peter Lu

Chemistry Faculty Publications

We report a new approach of 2D regional correlation analysis capable of analyzing fluctuation dynamics of complex multiple correlated and anticorrelated fluctuations under a noncorrelated noise background. Using this new method, by changing and scanning the start time and end time along a pair of fluctuation trajectories, we are able to map out any defined segments along the fluctuation trajectories and determine whether they are correlated, anticorrelated, or noncorrelated; after which, a cross-correlation analysis can be applied for each specific segment to obtain a detailed fluctuation dynamics analysis. We specifically discuss an application of this approach to analyze single-molecule fluorescence …

Analyzing The Catalytic Mechanism Of The Fe-Type Nitrile Hydratase From Comamonas Testosteroni Ni1, Saroja Rao, Richard C. Holz

Chemistry Faculty Research and Publications

In order to gain insight into the catalytic mechanism of Fe-type nitrile hydratases (NHase), the pH and temperature dependence of the kinetic parameters k_cat, K_m, and k_cat/K_m along with the solvent isotope effect were examined for the Fe-type NHase from Comamonas testosteroni Ni1 (CtNHase). CtNHase was found to exhibit a bell-shaped curve for plots of relative activity vs pH over pH values 4−10 for the hydration of acrylonitrile and was found to display maximal activity at pH ∼7.2. Fits of these data provided a pK_ES1 value of …

Defining Resonance Raman Spectral Responses To Substrate Binding By Cytochrome P450 From Pseudomonas Putida, Piotr J. Mak, Daniel Kaluka, Munyaradzi Edith Manyumwa, Haiqing Zhang, Tianjing Deng, James R. Kincaid

Chemistry Faculty Research and Publications

Resonance Raman spectra are reported for substrate-free and camphor-bound cytochrome P450cam and its isotopically labeled analogues that have been reconstituted with protoheme derivatives that bear -CD₃ groups at the 1, 3, 5, and 8-positions (d12-protoheme) or deuterated methine carbons (d4-protoheme). In agreement with previous studies of this and similar enzymes, substrate binding induces changes in the high frequency and low frequency spectral regions, with the most dramatic effect in the low frequency region being activation of a new mode near 367 cm⁻¹. This substrate-activated mode had been previously assigned as a second “propionate bending” mode (Chen et …

Temperature Dependence Investigation Of Dissipation Processes In Strongly Anisotropic High-Temperature Superconductors Of Bi-Pb-Sr-Ca-Cu-O System Synthesized Using Solar Energy, J Chigvinadze, Juana Acrivos, S. Ashimov, D. Gulamova, T. Machaidze, D Uskenbaev

Faculty Publications, Chemistry

The investigation of temperature dependence of damping and period of vibrations of HTSC superconductive cylinder of Bi-Pb-Sr-Ca-Cu-O system suspended by a thin elastic thread and performing axial-torsional vibrations in a magnetic field at temperatures above the critical one for the main phase Tc=107 K were carried out. It was observed some "chaos" temperature region in the temperature interval 107-138 K, where it is seen separate ripples of dissipation and oscillation frequency. It is assumed that the "chaos" region could point to a possibility of existence of other magnetic and more high-temperature phases as single islands in a normal materials matrix.

Halothiobacillus Neapolitanus Carboxysomes Sequester Heterologous And Chimeric Rubisco Species, Balaraj B. Menon, Zhicheng Dou, Sabine Heinhorst, Jessup M. Shively, Gordon C. Cannon

Faculty Publications

Background: The carboxysome is a bacterial microcompartment that consists of a polyhedral protein shell filled with ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO), the enzyme that catalyzes the first step of CO(2) fixation via the Calvin-Benson-Bassham cycle. Methodology/Principal Findings: To analyze the role of RubisCO in carboxysome biogenesis in vivo we have created a series of Halothiobacillus neapolitanus RubisCO mutants. We identified the large subunit of the enzyme as an important determinant for its sequestration into alpha-carboxysomes and found that the carboxysomes of H. neapolitanus readily incorporate chimeric and heterologous RubisCO species. Intriguingly, a mutant lacking carboxysomal RubisCO assembles empty carboxysome shells of …

Ex Situ Variable Angle Spectroscopic Ellipsometry Studies On Chemical Vapor Deposited Boron-Doped Diamond Films: Layered Structure And Modeling Aspects, S. Gupta, A. Dudipala, O. A. Williams, K. Haenen, Eric W. Bohannan

Chemistry Faculty Research & Creative Works

We report the optical property measurements on boron-doped diamond (BDD) films which were synthesized by microwave plasma-assisted chemical vapor deposition technique on Si (100) using methane in high hydrogen dilution and trimethylboron as precursors with varying boron concentration such that [B] [C]gas =100, 500, 1000, 2000, 4000, and 6467 ppm. These BDD films were investigated using a rotating analyzer variable angle spectroscopic ellipsometry (SE) from the near IR to UV range (830-193 nm). by applying the conventional Bruggeman effective medium approximation and linear regression analyses to the raw SE data that is, [ψ (λi),Δ (λi)] and pseudodielectric function (〈 εr …

Polymeric Paracest Agents For Enhancing Mri Contrast Sensitivity, Yunkou Wu, Youfu Zhou, Olivier Quari, Mark Woods, Piyu Zhao, Todd B. Soesbe, Garry Kiefer, A. Dean Sherry

Chemistry Faculty Publications and Presentations

Linear polymers of PARACEST agents were prepared by using classical free radical chain polymerization conditions. The Eu³⁺-polymers exhibited similar intermediate-to-slow water exchange and CEST characteristics as the Eu³⁺-monomers. This provided an avenue to lower the detection limit of these imaging agents substantially and makes them potentially useful as MRI sensors for molecular imaging.

Antibacterial Activity Of Dipeptide Constructions Of Acetylsalicylic Acid And Nicotinic Acid, Ronald Bartzatt, Suat L.G. Cirillo, Jeffrey D. Cirillo

Chemistry Faculty Publications

Two dipeptide drugs are synthesized utilizing an acetylsalicylic acid or nicotinic acid molecule for the framework. A D-alanine-D-alanine dipeptide moiety is attached to the carbonyl carbon of acetylsalicylic acid (I) and nicotinic acid (II). Dipeptide derivatives (I) and (II) showed significant reduction of Escherichia coli (E. coli) bacterial growth and colony-forming units. A mixture of (I) and (II) induced growth inhibition of 8%, 17.5%, 28%, and 42.5% at concentrations of 100, 200, 300, and 400 μg/mL, respectively. Ampicillin demonstrated much less growth inhibition of this penicillin-resistant E. coli bacteria. Derivatives (I) and (II) showed significant reduction of colony-forming units at …

Simple Inhibitors Of Histone Deacetylase Activity That Combine Features Of Short-Chain Fatty Acid And Hydroxamic Acid Inhibitors, Jessica L. Tischler, Basel Abuaita, Sierra C. Cuthpert, Christopher Fage, Kristi Murphy, Andrew Saxe, Edward B. Furr, Jamie Hedrick, Jennifer Meyers, David Snare, Ali R. Zand

Chemistry & Biochemistry Publications

Butyric acid and trichostatin A (TSA) are anti-cancer compounds that cause the upregulation of genes involved in differentiation and cell cycle regulation by inhibiting histone deacetylase (HDAC) activity. In this study we have synthesized and evaluated compounds that combine the bioavailability of short-chain fatty acids, like butyric acid, with the bidentate binding ability of TSA. A series of analogs were made to examine the effects of chain length, simple aromatic cap groups, and substituted hydroxamates on the compounds' ability to inhibit rat-liver HDAC using a fluorometric assay. In keeping with previous structure-activity relationships, the most effective inhibitors consisted of longer …

Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University

Chemistry & Biochemistry Newsletter: 2002-2015

Inside:

Page 2 PlainGreen Conference 2008; Dioszegi attends ACS Green Chemistry Summer School

Page 3 SDSU seeks CLS/Medical Tech accreditation; Pravecek named South Dakota’s ASCLS Member of the Year

Page 4 You awarded grant from Board of Regents; Recent Faculty Publications

Page 5 New Grad Students

Page 6 Native American traditional tea has health benefits; Natalie Garry is SDSU August Career Service Employee

Page 7 Henry A. Lardy Lecture; SDSU offers master’s degree in chemistry education; Grad students attend Green Chemistry and Engineering Conference

Page 8 New Shepard Hall Update