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Electrochemical Glucose Sensors—Developments Using Electrostatic Assembly And Carbon Nanotubes For Biosensor Construction, Alice Harper, Mark Anderson 2009 Berry College

Electrochemical Glucose Sensors—Developments Using Electrostatic Assembly And Carbon Nanotubes For Biosensor Construction, Alice Harper, Mark Anderson

Mark R. Anderson

In 1962, Clark and Lyons proposed incorporating the enzyme glucose oxidase in the construction of an electrochemical sensor for glucose in blood plasma. In their application, Clark and Lyons describe an electrode in which a membrane permeable to glucose traps a small volume of solution containing the enzyme adjacent to a pH electrode, and the presence of glucose is detected by the change in the electrode potential that occurs when glucose reacts with the enzyme in this volume of solution. Although described nearly 50 years ago, this seminal development provides the general structure for constructing electrochemical glucose sensors that is ...


Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Michael Nichols, Mark Waner 2009 John Carroll University

Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Michael Nichols, Mark Waner

Michael A Nichols

An extension of the classic keto−enol tautomerization of β-dicarbonyl compounds into a kinetic analysis of deuterium exchange is presented. It is shown that acetylacetone and ethyl acetoacetate undergo nearly complete deuterium exchange of the α-methylene carbon when dissolved in methanol-d4. The extent of deuteration may be monitored via NMR spectroscopy as a function of time. A mechanism for deuterium exchange is presented and shown to be consistent with a consecutive first-order process. The data for acetylacetone are consistent with steady-state kinetics, whereas those of ethyl acetoacetate illustrate nonsteady-state behavior, offering an accessible example where students might collect and analyze ...


Bismuth Compounds In Organic Synthesis: Synthesis Of Dioxanes, Dioxepines, And Dioxolanes Catalyzed By Bismuth(Iii) Triflate, Ram Mohan, Daniel Podgorski, Scott Krabbe, Long Le, Paul Sierszulski 2009 Illinois Wesleyan University

Bismuth Compounds In Organic Synthesis: Synthesis Of Dioxanes, Dioxepines, And Dioxolanes Catalyzed By Bismuth(Iii) Triflate, Ram Mohan, Daniel Podgorski, Scott Krabbe, Long Le, Paul Sierszulski

Ram S. Mohan

A simple method for the synthesis of l,3-dioxolanes from carbonyl compounds has been developed using l,2-bis(trimethylsilyloxy) ethane in the presence of bismuth (III) triflate as a catalyst. The bismuth(III) triflate catalyzed synthesis of a range of dioxanes and dioxepines has also been developed. In these latter cases, the carbonyl compound is treated with a diol, and triethyl orthoformate is used as a water scavenger. All these methods avoid the use of a Dean-Stark trap.


The Effect Of Ion-Pairing On The Open Circuit Potential Of 3-Mercaptoproprionic Acid Modified Gold Electrodes, Mark Anderson, Alice Harper 2009 Kennesaw State University

The Effect Of Ion-Pairing On The Open Circuit Potential Of 3-Mercaptoproprionic Acid Modified Gold Electrodes, Mark Anderson, Alice Harper

Mark R. Anderson

Open circuit potential (OCP) measurement is used to monitor the charge of a monolayer of 3-mercaptopropionic acid. OCP is determined by the concentrations of the reduced and oxidized forms of a redox couple in the solution adjacent to the modified interface. OCP values were monitored in the presence of the one-electron redox couple Fe(CN)63-/4- as a function of solution pH. The OCP measured at basic pHs was different from the acidic OCP due to differences in electrostatic interactions between the interface and the redox species as described by the Nernst equation. The influence of ion-pairing with the ...


Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Mark Waner, Michael Nichols 2009 John Carroll University

Kinetic And Mechanistic Studies Of The Deuterium Exchange In Classical Keto−Enol Tautomeric Equilibrium Reactions, Mark Waner, Michael Nichols

Mark J. Waner

An extension of the classic keto−enol tautomerization of β-dicarbonyl compounds into a kinetic analysis of deuterium exchange is presented. It is shown that acetylacetone and ethyl acetoacetate undergo nearly complete deuterium exchange of the α-methylene carbon when dissolved in methanol-d4. The extent of deuteration may be monitored via NMR spectroscopy as a function of time. A mechanism for deuterium exchange is presented and shown to be consistent with a consecutive first-order process. The data for acetylacetone are consistent with steady-state kinetics, whereas those of ethyl acetoacetate illustrate nonsteady-state behavior, offering an accessible example where students might collect and analyze ...


Phytoprotective Influence Of Bacteria On Growth And Cadmium Accumulation In The Aquatic Plant Lemna Minor, Julian Tyson, Lisa M. Stout, Elena N. Dodova, Klaus Nusslein 2009 University of Massachusetts - Amherst

Phytoprotective Influence Of Bacteria On Growth And Cadmium Accumulation In The Aquatic Plant Lemna Minor, Julian Tyson, Lisa M. Stout, Elena N. Dodova, Klaus Nusslein

Julian Tyson

Certain plants are known to accumulate heavy metals, and can be used in remediation of
polluted soil or water. Plant-associated bacteria, especially those that are metal tolerant,
may enhance the total amount of metal accumulated by the plant, but this process is still
unclear. In this study, we investigated metal enhancement vs. exclusion by plants, and the
phytoprotective role plant-associated bacteria might provide to plants exposed to heavy
metal. We isolated cadmium-tolerant bacteria from the roots of the aquatic plant Lemna
minor grown in heavy metal-polluted waters, and tested these isolates for tolerance to
cadmium. The efficiency of plants to ...


Mid-Gap Electronic States In Zn1-Xmnxo., C. A. Johnson, Kevin R. Kittilstved, T. C. Kaspar, T. C. Droubay, S. A. Chambers, G. M. Salley, D. R. Gamelin 2009 University of Massachusetts - Amherst

Mid-Gap Electronic States In Zn1-Xmnxo., C. A. Johnson, Kevin R. Kittilstved, T. C. Kaspar, T. C. Droubay, S. A. Chambers, G. M. Salley, D. R. Gamelin

Kevin R. Kittilstved

Electronic absorption, magnetic circular dichroism (MCD), photoconductivity, and valence-band x-ray photoelectron (XPS) spectroscopic measurements were performed on epitaxial Zn1−xMnxO films to investigate the origin of the mid-gap band that appears upon introduction of Mn2+ into the ZnO lattice. Absorption and MCD spectroscopies reveal Mn2+-related intensity at energies below the first excitonic transition of ZnO, tailing well into the visible energy region, with an onset at ∼2.2 eV. Photoconductivity measurements show that excitation into this visible band generates mobile charge carriers, consistent with assignment as a Mn2+/3+ photoionization transition. XPS measurements reveal the presence of occupied Mn2 ...


Array-Based Sensing Of Normal, Cancerous, And Metastatic Cells Using Conjugated Fluorescent Polymers, A Bajaj, OR Miranda, R Phillips, IB Kim, DJ Jerry, UHF Bunz, VM Rotello 2009 University of Massachusetts - Amherst

Array-Based Sensing Of Normal, Cancerous, And Metastatic Cells Using Conjugated Fluorescent Polymers, A Bajaj, Or Miranda, R Phillips, Ib Kim, Dj Jerry, Uhf Bunz, Vm Rotello

Vincent Rotello

A family of conjugated fluorescent polymers was used to create an array for cell sensing. Fluorescent conjugated polymers with pendant charged residues provided multivalent interactions with cell membranes, allowing the detection of subtle differences between different cell types on the basis of cell surface features. Highly reproducible characteristic patterns were obtained from different cell types as well as from isogenic cell lines, enabling the identification of the cell type as well differentiating between normal, cancerous, and metastatic isogenic cell types with high accuracy.


Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl 2009 University of Massachusetts - Amherst

Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl

Otto Vogl

No abstract provided.


My Italian Connections: Otto Vogl In Italy, Otto Vogl, Gerald S. Kirshenbaum 2009 University of Massachusetts - Amherst

My Italian Connections: Otto Vogl In Italy, Otto Vogl, Gerald S. Kirshenbaum

Otto Vogl

This document describes Otto Vogl's work in Italy. From 1975, Vogl served for 3 years as the Chairman of the Scientific Advisory Committee to the President Italo Trapasso of the Plastic Materials Company of Montedison SA, Milan, Italy. He was assigned to restructure the research activities and to organize the Research Division. He was responsible for the appointment of DiDrusco as the Vice President of Research and Paolo Galli as the Director of Research at the company’s facilities in Ferrara. Within a year of Vogl’s reorganization of the research organization the high yield catalyst for the polymerization ...


A Mild And Chemoselective Method For The Deprotection Of Tert-Butyldimethylsilyl (Tbdms) Ethers Using Iron(Iii) Tosylate As A Catalyst, Ram S. Mohan, Jason M. Bothwell, Veronica V. Angeles, James P. Carolan, Margaret E. Olson 2009 Illinois Wesleyan University

A Mild And Chemoselective Method For The Deprotection Of Tert-Butyldimethylsilyl (Tbdms) Ethers Using Iron(Iii) Tosylate As A Catalyst, Ram S. Mohan, Jason M. Bothwell, Veronica V. Angeles, James P. Carolan, Margaret E. Olson

Ram S. Mohan

The most common method for the deprotection ofTBDMS ethers utilizes stoichiometric amounts of tetrabutylammonium fluoride, n-Bu4N+F(TBAF), which is highly corrosive and toxic. We have developed a mild and chemoselective method for the deprotection ofTBDMS, TES, and TIPS ethers using iron(III) tosylate as a catalyst. Phenolic TBDMS ethers, TBDPS ethers and the BOC group are not affected under these conditions. Iron(III) tosylate is an inexpensive, commercially available, and non-corrosive reagent.


Iron(Iii) Tosylate-Catalyzed Deprotection Of Aromatic Acetals In Water, Ram S. Mohan, Margaret E. Olson, James P. Carolan, Michael V. Chiodo, Phillip R. Lazzara 2009 Illinois Wesleyan University

Iron(Iii) Tosylate-Catalyzed Deprotection Of Aromatic Acetals In Water, Ram S. Mohan, Margaret E. Olson, James P. Carolan, Michael V. Chiodo, Phillip R. Lazzara

Ram S. Mohan

The deprotection of aromatic as well as conjugated acetals and ketals in water is catalyzed by iron(III) tosylate (1.0–5.0 mol %). Iron(III) tosylate is an inexpensive and readily available catalyst. The use of water, the most environmentally benign solvent, makes this procedure especially attractive for acetal deprotection.


In Your Element: Green Bismuth, Ram S. Mohan 2009 Illinois Wesleyan University

In Your Element: Green Bismuth, Ram S. Mohan

Ram S. Mohan

No abstract provided.


Molecular Characteristics Of Phosphoric Acid Treated Soils, Amin Eisazadeh, Khairul Anuar Kassim, Hadi Nur 2009 University Technology Malaysia

Molecular Characteristics Of Phosphoric Acid Treated Soils, Amin Eisazadeh, Khairul Anuar Kassim, Hadi Nur

Hadi Nur

The expansive nature of soils containing high amounts of clay minerals can be altered through chemical stabilization, resulting in a material suitable for construction purposes. The primary objective of this investigation was to study the changes induced in the molecular structure of phosphoric acid stabilized bentonite and lateritic soil using Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR) spectroscopy. Based on the obtained data, it was found that a surface alteration mechanism was the main reason responsible for the improvement of treated soils. Furthermore, the results indicated that the Al present in the octahedral layer of clay minerals were ...


Cyclohexane Oxidation And Cyclohexyl Hydroperoxide Decomposition By Poly(4-Vinylpyridine-Co-Divinylbenzene) Supported Cobalt And Chromium Complexes, Zeljko D. Cupic 2009 Institute of Chemistry, Technology and Metallurgy

Cyclohexane Oxidation And Cyclohexyl Hydroperoxide Decomposition By Poly(4-Vinylpyridine-Co-Divinylbenzene) Supported Cobalt And Chromium Complexes, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


Reallocation Of Mesh Points In Fluid Problems Using Back-Propagation Algorithm, Philadelphia University 2009 Philadelphia University

Reallocation Of Mesh Points In Fluid Problems Using Back-Propagation Algorithm, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Bismuth(Iii) Bromide In Organic Synthesis. A Catalytic Method For The Allylation Of Tetrahydrofuranyl And Tetrahydropyranyl Ethers, Ram S. Mohan, Scott W. Krabbe, Veronica V. Angeles 2009 Illinois Wesleyan University

Bismuth(Iii) Bromide In Organic Synthesis. A Catalytic Method For The Allylation Of Tetrahydrofuranyl And Tetrahydropyranyl Ethers, Ram S. Mohan, Scott W. Krabbe, Veronica V. Angeles

Ram S. Mohan

A bismuth bromide-catalyzed (10.0 mol %) multicomponent reaction involving the allylation of THF- and THP-ethers, followed by in situ derivatization with acetic anhydride to generate highly functionalized esters has been developed under solvent-free conditions. To the best of our knowledge, this is the first report of a catalytic procedure for the allylation of THF- and THP-ethers to yield ring-opened products.


Ru(Iii), Pd(Ii), Pt(Iii) And Pt(Iv) Complexes Of A Novel 32-Membered Unsymmetrical Macrocyclic Ligand, Mohammad Mansoob Khan Dr 2009 Universiti Brunei Darussalaam

Ru(Iii), Pd(Ii), Pt(Iii) And Pt(Iv) Complexes Of A Novel 32-Membered Unsymmetrical Macrocyclic Ligand, Mohammad Mansoob Khan Dr

Dr. Mohammad Mansoob Khan

Reactions of [N12] macrocyclic ligand, L·2HClO4, with RuCl3, PdCl2, K2[PtCl6], [K2PtCl4] as well as [M(Ph3P)2Cl2] (M = Pd or Pt), and [Ru(Ph3P)3Cl2] produces bimetallic complexes whose analytical data are consistent with the molecular formulae as Ru2LCl4(ClO4)2 (I), Pd2LCl2(ClO4)2 (II), Pt2LCl6(ClO4)2 (III), Pt2LCl2(ClO4)2 (IV) and Ru2LCl2(ClO4)2 (V). Reactions of the ligand with the precursors [M(Ph3P)2Cl2] (M = Pd or Pt), and [Ru(Ph3P)3Cl2], has released all the Ph3P ancillary ligand in solution. Magnetic moment, IR and UV-visible spectroscopic data confirms the encapsulation of metal ...


Mining And Civilization, An Illustrated History, Fathi Habashi 2009 Laval University, Quebec City, Canada

Mining And Civilization, An Illustrated History, Fathi Habashi

Fathi Habashi

Mining and Civilization has been conceived to compliment the author's two books History of Metallurgy and Readings in Historical Metallurgy and to fill a gap in the literature. It is difficult to study the history of metallurgy without studying the history of mining at the same time. Each time the author visits ancient ruins or examines an ancient stone statue he recalls the work of miners who brought the material from a quarry so that the sculptor can create a work of art. History of mining, quarrying, and stone carving is history of civilization.


Impact Of The Australia-Us Free Trade Agreement On Australian Medicines Regulation And Prices, Thomas A. Faunce, James Bai, Duy Nguyen 2009 Australian National University

Impact Of The Australia-Us Free Trade Agreement On Australian Medicines Regulation And Prices, Thomas A. Faunce, James Bai, Duy Nguyen

Thomas A Faunce

The Australia – United States Free Trade Agreement (AUSFTA) came into force on 1 January 2005. Before and subsequently to the AUSFTA being concluded, controversy surrounded the debate over its impact on Australia ’ s health policy, specifically on regulation of pharmaceutical patents and Australia ’ s cost-effectiveness system relating to prescription medicine prices known as the Pharmaceutical Benefits Scheme (PBS). This article examines the expectations of both parties in the pharmaceutical sector with regard to the AUSFTA, as well as how successfully they were achieved. It seeks to analyse important relevant outcomes for regulators, the public and pharmaceutical industry, as well as ...


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