5th Annual Texas A&M University System Pathways to the Doctorate Student Research Symposium
November 2-3, 2007
Hosted by Tarleton State University

Abstracts of Student Presentations: Physical Sciences

O'DELL HICKS. "A Quantitative NMR Experiment: Determination of Solvent Purity"
Faculty Mentors: Dr. Peter Bell, Dr. Linda Schultz

Some of the earliest applications of Nuclear Magnetic Resonance Spectroscopy involved quantitative analysis of mixtures, but NMR is currently regarded primarily as a qualitative tool for the elucidation of molecular structures.  However, quantitative NMR, qNMR, is regaining recognition as an analytical technique.  Unfortunately, most published quantitative NMR experiments involve the use of toxic solvents, such as CDCl3, or carcinogenic compounds, such as benzene.  An undergraduate quantitative NMR experiment has been developed using D2O as the solvent and less toxic compounds as analytes.

The relative concentrations in a mixture of two pure anhydrous compounds in D2O are determined from their relative integration ratios using 1H NMR.  Then a mixture of one of these anhydrous compounds and a sample of an impure compound is analyzed to determine the percent purity of the second component by using the pure compound as an internal standard.  The purity of many common solvents can be determined rapidly, at the percent level, by this technique.  Solvents analyzed in this manner include acetone, ethyl alcohol, methyl alcohol, tetrahydrofuran, and N,N-dimethylformamide.  The best internal standard compound was found to be dimethylsulfoxide.


AVERY MCCHRISTIAN. "A Study of Eclipsing Binary Star WY Tau."
Faculty Mentor: Dr. Shaukat Goderya

The Tarleton State University observatory is located at the Hunnewell Ranch about 12 miles from the campus near the intersection of TX 205 and CR 181. It was completed in December of 2005 and is now fully operational and is being used for teaching as well as astronomical research. The observatory is equipped with a 32 inch (.8m) research grade remotely controlled telescope from ACE, and a high quality FINGERLAKES CCD camera and UBVRI filters from custom scientific. During the months of November and December 2006 the observatory was used to observe a poorly studied eclipsing binary system known as WY TAU in the constellation of Taurus the Bull. This system is the first to be observed by the TSU Observatory since it began operation.  Eclipsing binary stars play a vital role in our understanding of the evolution and properties of stars. Our preliminary analysis shows that WY TAU is a contact type eclipsing binary system with a period of 0.6929995 days. In this poster we present the work that has been done so far on photometric data analysis of the system.


CLIFFORD TERRELL and LAURA ROGERS. "A College Chemistry Lab Experiment Developed from a Classic Demonstration."
Faculty Mentor: Dr. Linda Schultz

The “Blue Bottle” is a classic chemical demonstration in which glucose is reacted with methylene blue in a basic solution.  The reaction flask is stoppered and shaken, and a blue color is formed by oxidation of the methylene blue by dissolved oxygen.  When the dissolved oxygen is exhausted, the color vanishes, but reappears when the flask is shaken again.  The process can be repeated many times.

A procedure has been developed in which oxygen concentrations are controlled to measure reaction rates.  A large lab can be divided into groups with differing concentrations of methylene blue and sodium hydroxide to enable determination of the rate law by the method of initial rates.  The entire lab then works as a group to deduce the mechanism.  This experiment allows students to observe a zero order reaction and deduce the presence of intermediates and catalysts.