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Chemistry

Selected Works

Selected Works

1999

Articles 1 - 13 of 13

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Development And Student Use Of Web-Based Prelabs In Analytical Chemistry Courses, Mark Anderson, Brian Tissue Sep 1999

Development And Student Use Of Web-Based Prelabs In Analytical Chemistry Courses, Mark Anderson, Brian Tissue

Mark R. Anderson

No abstract is currently available.

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Ab Initio Calculation Of 81Br Nqr Transition Frequencies Of Brominated Aromatics (Flame Retardants), Chris R. Harwell, Anthony A. Mrse, Leslie G. Butler, Randall W. Hall Sep 1999

Ab Initio Calculation Of 81Br Nqr Transition Frequencies Of Brominated Aromatics (Flame Retardants), Chris R. Harwell, Anthony A. Mrse, Leslie G. Butler, Randall W. Hall

Randall W. Hall

Brominated aromatics, used extensively as flame retardants, have been studied with 81Br nuclear quadrupole resonance (NQR) spectroscopy. NQR requires lengthy frequency searches because 81Br NQR transition frequencies in brominated aromatics are spread over a wide (40 MHz) range. We investigate the ability of ab initio calculations to narrow this search range by predicting 81Br NQR transition frequencies for a series of brominated aromatics, using restricted Hartree−Fock (RHF) and Becke's three-parameter Lee−Yang−Parr density functional theory hybrid method (B3LYP). Basis sets used are of double and triple-ζ quality with varying degrees of polarization included on bromine. Geometries are the isolated molecules, with …

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The Discovery-Oriented Approach To Organic Chemistry. 2. Selectivity In Alcohol Oxidation. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Steven R. Shadwick Jul 1999

The Discovery-Oriented Approach To Organic Chemistry. 2. Selectivity In Alcohol Oxidation. An Exercise In 1H Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Steven R. Shadwick

Ram S. Mohan

We have developed a simple oxidation experiment that presents the student with a puzzle and is a good exercise in 1H NMR spectroscopy. The experiment, which illustrates the important concept of selectivity in organic synthesis, involves selective oxidation of a mixture of 1-heptanol and 2-heptanol using commercial swimming pool chlorine. 1H NMR analysis of the product mixture allows the student to determine the selectivity exhibited by the reagent.

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Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof. Jun 1999

Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The objective of this study was the research of novel and inexpensive sources of polysaccharides degrading enzymes such as amylases and glucanases from local plants in order to justify their biotechnological applications. The isolation of two l3-amylases and an endo-1,3-ß-D-glucanase was reached using common protein purification methods such as buffer extraction, ammonium sulfate fractionation, ionexchange and gel filtration chromatographies. The methods used were simple and easily reproducible, suggesting the possibilfty of large-scale production. ln the crude extract of Curculigo pilosa tuber, only ß-amylase was detected as starch degrading enzyme and its activity was approximately 282 Uig of fresh material. The …

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Reference Materials For Calorimetry And Differential Thermal Analysis, R. Sabbah, An Xu-Wu, J.S. Chickos, M.L.Planas Leitão, M.V. Roux, L.A. Torres May 1999

Reference Materials For Calorimetry And Differential Thermal Analysis, R. Sabbah, An Xu-Wu, J.S. Chickos, M.L.Planas Leitão, M.V. Roux, L.A. Torres

James Chickos

No abstract provided.

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Voltammetry Of Metallofullerenes And Higher Fullerenes, Mark Anderson, Harry Dorn, Steven Stevenson, Susanne Dana May 1999

Voltammetry Of Metallofullerenes And Higher Fullerenes, Mark Anderson, Harry Dorn, Steven Stevenson, Susanne Dana

Mark R. Anderson

No abstract is currently available.

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The Correlation Of Physical Properties Of Organic Molecules With Computed Molecular Surface Areas., Robert Mebane, Shannon Schanley, Thomas Rybolt, Chrystal Bruce Apr 1999

The Correlation Of Physical Properties Of Organic Molecules With Computed Molecular Surface Areas., Robert Mebane, Shannon Schanley, Thomas Rybolt, Chrystal Bruce

Chrystal D. Bruce

The objective of this paper is to show that a student's understanding of molecular properties can be enhanced with the study of molecular surface areas obtained from readily available molecular modeling software.

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The Discovery-Oriented Approach To Organic Chemistry 1. Nitration Of Unknown Organic Compounds. An Exercise In 1H Nmr And 13C Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Sonia R. Mcelveen, Kostas Gavardinas, Jean A. Stamberger Mar 1999

The Discovery-Oriented Approach To Organic Chemistry 1. Nitration Of Unknown Organic Compounds. An Exercise In 1H Nmr And 13C Nmr Spectroscopy For Sophomore Organic Laboratories, Ram S. Mohan, Sonia R. Mcelveen, Kostas Gavardinas, Jean A. Stamberger

Ram S. Mohan

Nitration is one of the most fundamental reactions in organic chemistry. However, the majority of the nitration experiments found in the standard lab textbooks are of the "cookbook" variety and convey none of the excitement associated with discovery in experimental chemistry. We have developed two simple nitration experiments that present the student with a puzzle and are a good exercise in 1H NMR and 13C NMR spectroscopy. 13 C NMR spectroscopy is a powerful structure elucidation tool and yet not many examples of the use of 13C NMR spectroscopy in organic lab experiments can be found. The experiment involves nitration …

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Changes In The Fermi Surface At The Magnetization Reorientation Transition In Fe/Cu(100), Reginaldt H. Madjoe, Alexey N. Koveshnikov, Christopher Harwell, Randall W. Hall, Roger L. Stockbauer, Richard L. Lutz Dec 1998

Changes In The Fermi Surface At The Magnetization Reorientation Transition In Fe/Cu(100), Reginaldt H. Madjoe, Alexey N. Koveshnikov, Christopher Harwell, Randall W. Hall, Roger L. Stockbauer, Richard L. Lutz

Randall W. Hall

We present a study of the evolution of the valence bandstructure of Fe/Cu(100) as a function of Fe coverage in the 0–12 monolayer range. Angle-resolved photoelectron spectroscopy was used to probe the valence electronic structure and to extract Fermi surface contours as a function of increasing Fe coverage. The first few monolayers show Fe-induced densities of states that are significantly different from those in thicker films. At 5 ML, distinct changes occur in the Fermi surface, where a magnetization reorientation transition has been observed previously.

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Single-Crystal 27Al Nmr Of Andalusite And Calculated Electric Field Gradients: The First Complete Nmr Assignment For A 5-Coordinate Aluminum Site, Pamela L. Bryant, Chris R. Harwell, Katherine Wu, Frank R. Fronczek, Randall W. Hall, Leslie G. Butler Dec 1998

Single-Crystal 27Al Nmr Of Andalusite And Calculated Electric Field Gradients: The First Complete Nmr Assignment For A 5-Coordinate Aluminum Site, Pamela L. Bryant, Chris R. Harwell, Katherine Wu, Frank R. Fronczek, Randall W. Hall, Leslie G. Butler

Randall W. Hall

Andalusite, Al2SiO5, contains 5- and 6-coordinate aluminum sites, and is a preeminent model for 27 Al NMR spectroscopy. We describe a combined NMR, crystallography, and theory project:  single-crystal 27 Al NMR spectra at 298 K, the crystal structure of andalusite at 115 K, and electric field gradient calculations. The low-symmetry 5-coordinate site is a stiff test of the computational methods. In addition, the chemical shift tensor is measured for the 5-coordinate site. The small body of 27 Al NMR data, especially for rare 5-coordinate sites, inspires the calculation of NMR parameters. We explore the accuracy of two approaches for 27 …

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The Hofmann Rearrangement Using Household Bleach: Synthesis Of 3-Nitroaniline, Ram S. Mohan, Keith A. Monk Dec 1998

The Hofmann Rearrangement Using Household Bleach: Synthesis Of 3-Nitroaniline, Ram S. Mohan, Keith A. Monk

Ram S. Mohan

No abstract provided.

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Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram S. Mohan, Steven A. Tymonko, Bryce A. Nattier Dec 1998

Oxidation Of Benzoins To Benzils Using Bismuth(Iii) Nitrate-Copper(Ii) Acetate, Ram S. Mohan, Steven A. Tymonko, Bryce A. Nattier

Ram S. Mohan

Benzoins are oxidized to benzils in excellent yields by 0.4 equivalents of Bi(NO3)3.5H20 and 4 mol% of Cu(OAc)23)3.5H20 is a stable, inexpensive, commercially available solid. The relatively low cost and low toxicity of bismuth(Ill) nitrate makes this procedure a particularly attractive method for oxidation of benzoins.

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Contraction Of The Model For The Bray-Liebhafsky Oscillatory Reaction By Eliminating Intermediate I2o, Zeljko D. Cupic Dec 1998

Contraction Of The Model For The Bray-Liebhafsky Oscillatory Reaction By Eliminating Intermediate I2o, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.

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