Recently, the University received a $50,000 grant to add a mass spectrometer to our new Shimadzu Liquid Chromatograph equipped with an autosampler and fraction collector. A number of research projects involve the use of this state-of-the-art LCMS. In addition the Department recently received a powder x-ray diffractometer for the determination of crystal structures. These instruments complement the wide range of advanced instruments available for student education and research. These include a gas chromatograph/mass spectrometer, three additional gas chromatographs, a FT nuclear magnetic resonance spectrometer, two IR spectrometers, an atomic absorption spectrometer, and many other instruments.
Atmospheric and Space Research Team (Research Website)
Operating under the leadership of Dr. Ed Wilson, Professor of Chemistry and Dr. James Mackey, Professor of Physics, the team's research is funded by grants from NASA Astrobiology Science and Technology Instrument Development (ASTID), NASA Experimental Program to Stimulate Cooperative Research (EPSCoR), and the Arkansas Space Grant Consortium.
Through this research, Harding University undergraduate students gain valuable hands-on experience and knowledge in chemistry and physics. Current research projects include analysis of hybrid rocket motor exhaust plumes, development of a distributed spectrometer for use on a future NASA rover mission to Mars, and studies of atmospheric chemical reaction kinetics, and are explained in brief below.
Hybrid Rocket Motors
With research focusing on non-invasive measurements of a chemical rocket motor, measurements will be made on UALR's HTPB/oxygen hybrid rocket motor as well as on a minihybrid designed by Harding students designed to the effects of scaling the rocket down. A "snap-shot" UV-Vis spectrometer will be designed to give real time measurement of temperature and species in both the plume and the combustion chamber. A laser diode infrared spectrometer will be developed to look at both water and carbon dioxide in the plume.
Atmospheric Chemical Kinetics
People everywhere are concerned about global warming, stratospheric ozone depletion and ozone production in the lower atmosphere. Accurate assessment of the effects of pollutants requires the construction of mathematical models, which need the most accurate reaction rate data possible. The objective of this research is to measure the rate constants of nine pentanes with hydroxyl radical over the range +200C to -70C. Reaction with hydroxyl radicals is the first step in degradation and removal of pollutants from the atmosphere. Activation energies and pre-exponential factors will be calculated from the rate data, a stringent assessment and refinement of predictive rules of hydroxyl radical reaction rate constants can be made, including nuances due to chain branching and methylene group addition.
Distributed Spectrometer for Mars
We will develop a mobile science instrumentation system capable of doing wide-area surveys for the detection of biogenic gases that may serve as indicators of life on Mars. We will provide the capability to increase in situ measurement coverage and improve chances of detecting biosignatures by developing a distributed spectrometer instrument system employing a rover and lander. Gases to be probed include methane, ammonia, hydrogen sulfide, oxygen, carbon monoxide, sulfur dioxide, nitrous oxide and formaldehyde.
Further information on the research being done by Harding's Atmospheric and Space Research Team, as well as recent publications and funding information may be found at the research website.
Darah and Julianne working on a new infrared spectrometer for the Mars rover
Research with Dr. Dennis Matlock involves several projects aimed at elucidating the mechanism of action of DNA helicase enzymes. Dr. Matlock's research has been funded by The Arkansas Biomedical Research Infrastructure Network ($17,090), The Arkansas IDeA Network of Biomedical Research Excellence (Arkansas INBRE) ($17,838). Dr Matlock's latest work was published in the journal Biochemistry. [Dennis L. Matlock, Laxmi Yeruva, Alicia K. Byrd, Samuel G. Mackintosh, Clint Langston, Carrie Brown, Craig E. Cameron, Christopher J. Fischer and Kevin D. Raney Biochemistry 2010, 49 (10), pp 2097–2109]
Dr. Hollandsworth oversees undergraduate projects aimed at synthesizing lipophilic, stereoselective lactide polymerization catalysts and organic polymers containing sulfur and nitrogen. In the summer of 2010 two students received grants from the HU chemistry department and NASA-ASGC totaling around $10,000.
Synthesis of 3,5-divinyl-1,2,4-triazole
Tris-pyrazolyl-borate tin(II) chloride -- A precursor to lactide polymerization catalysts.
Students in Dr. Stewart's group have recently synthesized light emitting napthyl-substituted anthracenes. This ongoing synthetic effort involves extensive use of aryl coupling reactions. Interested students can talk with Dr. Stewart for more details. This project also offers a chance for collaboration with Dr. Hollandsworth doing DFT computations to determine the HOMO-LUMO gaps of these compounds.