Volume 8 Issues 2 and 3 September/December 2009

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https://doi.org/10.33697/ajur.2009.011

Review: Microwave-Promoted Organic Synthesis

https://doi.org/10.33697/ajur.2009.012

Author(s):

Andrew Loftin and Douglas Armstrong

Affiliation:

Department of Physical Sciences, Olivet Nazarene University, Bourbonnais, Illinois 60914 USA

ABSTRACT:

As of the last twenty years a new wave in organic chemistry has started to change the way people think about putting energy into a reaction mixture. Microwave-promoted organic synthesis is a fast, efficient method of heating a system in order to achieve the completion of a desired reaction. There are many different types of reactions that have been attempted using this method, and still many more to be tested. Microwave-promoted organic synthesis can help to produce high yields of products in a short time, while reducing side reactions and making workups easier. This paper discusses the many benefits of microwave-promoted organic synthesis and gives various examples.


The Free Base Extraction of Harmaline from Penganum harmala

https://doi.org/10.33697/ajur.2009.013

Author(s):

Alyssa Brobst, Jeremy Lewis, Brian Klett, Cathy Haustein, and James Shriver

Affiliation:

Department of Chemistry, Central College, Pella, Iowa 50219 USA

ABSTRACT:

Highly fluorescent and pharmaceutically significant Harmala alkaloids occur in several plants including Syrian Rue (Penganum harmala) and several species of passion flowers. We identified a relatively nontoxic and efficient method for extraction of the major harmala alkaloid components from Syrian Rue seeds using ethyl acetate and sodium bicarbonate. This produced free base harmala alkaloids. Verification was performed qualitatively by using High Performance Liquid Chromatography and NMR analysis.


An Investigation of the Structure Underlying Irreducible Devisors

https://doi.org/10.33697/ajur.2009.014

Authors and Affiliations:

Hilary Smallwood
Fort Lewis College, 1000 Rim Drive, Durango, Colorado 81301 USA

Drew Swartz
Department of Mathematical Sciences, Indiana University–Purdue University Fort Wayne, 2101 East Coliseum Avenue, Fort Wayne, Indiana 46805 USA

ABSTRACT:

In previous literature Coykendall & Maney, as well as Axtell & Stickles, have discussed the concept of irreducible divisor graphs of elements in domains and ring with zero-divisors respectively, with two different definitions. In this paper we seek to look at the irreducible divisor graphs of ring elements under a hybrid definition of the two previous ones—in hopes that this graph will reveal structure concerning irreducible divisors in rings with zero-divisors. We also compare the three graphs and examine in what respects they are related. Other graph-theoretic properties of this graph will also be discussed.


Crystallization and Preliminary X-ray Diffraction of a Halophilic Archaeal Malate Synthase

https://doi.org/10.33697/ajur.2009.015

Author(s):

Geoffrey Thomas, Kenneth Lamlenn, and Bruce R. Howard

Affiliation:

Department of Physical Science, Southern Utah University, Cedar City, Utah 84720 USA

ABSTRACT:

Malate synthases found in cells of the halophilic Archaea constitute a third isoform of this important metabolic enzyme, in addition to the well characterized A and G isoforms. They share little sequence similarity with these other two isoforms. Database searches using basic local alignments reveal relationships between isoforms A and G, but do not indicate a significant sequence relationship between members of this third isoform and those of isoform G, and only a distant relationship with members of isoform A. This third isoform, which we propose to call isoform H (Halophilic archaeal), is also significantly smaller in size: ~100 residues shorter than isoform A, and ~300 residues shorter than isoform G. Representatives of both isoform A and G have been structurally characterized, but no three-dimensional structural information exists for isoform H. Here we report the crystallization and preliminary X-ray diffraction from a crystal form of an H-isoform member, the malate synthase from the halophilic archaeon Haloferax volcanii, originally isolated from the mud of the Dead Sea. This crystal form diffracts well, and is amenable to single crystal X-ray analysis.


Gold Nanowires: Their Synthesis and Surface Plasmon Resonances

https://doi.org/10.33697/ajur.2009.016

Author(s):

Ali Faghih and Edo Waks

Affiliation:

Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742 USA

ABSTRACT:

The objective of the project was to fabricate gold nano-rods and study the optical properties of gold nano-particles when coupled to Indium Arsenide quantum dots. The gold nano-rods were synthesized by a seed-mediated growth method using CTAB and BDAC as the surfactants, and the feasibility of changing the aspect ratio of the rods and their Plasmon resonance frequency was studied by varying the concentrations of these two surfactants. Finally, gold nano-rods with longitudinal Plasmon resonance of 940 nm were synthesized. Next, we studied the feasibility of coupling gold nano-wires to indium arsenide quantum dots for investigating their optical properties and studying the spontaneous emission enhancement of InAs QDs in the presence of the plasmon resonances of gold nano-wires. The sample containing nano-wires coupled to quantum dots was excited by red laser, and the emission was passed through a spectrometer and the spectrum was obtained.


Band Gap Energy in Silicon

https://doi.org/10.33697/ajur.2009.017

Author(s):

Jeremy J. Low, Michael L. Kreider, Drew P. Pulsifer, Andrew S. Jones and Tariq H. Gilani

Affiliation:

Department of Physics, Millersville University, P. O. Box 1002, Millersville, Pennsylvania 17551 USA

ABSTRACT:

The band gap energy, Eg in silicon was found by exploiting the linear relationship between the temperature and voltage for the constant current in the temperature range of 275 K to 333 K. Within the precision of our experiment, the results obtained are in good agreement with the known value energy gap in silicon. The temperature dependence of Eg for silicon has also been studied.