Dr. Gordon Purser Office:  Keplinger M-259 Phone:  (918) 631-3331 E-mail:  gordon-purser@utulsa.edu Dr. Purser received his B.S. degree from the University of Texas in 1978 and his Ph.D. in Inorganic Chemistry from the University of Colorado in 1982. Dr. Purser began his teaching career with a one-year appointment at the California Polytechnic State University in San Luis Obispo, CA. He was a visiting professor at the University of Colorado - Denver for four years. Prior to joining the faculty at TU, he was an associate professor at Glendale College in Glendale, California where he taught for six years. Dr. Purser joined the Department of Chemistry at The University of Tulsa in August, 1993.  Dr. Purser’s research interests lie in the areas of solution kinetics and science education. Research Interests: Understanding factors that affect the rate of reduction of ClO2 and ClO2- by ferrous ion Quantifying the ability of melatonin to behave as an antioxidant Developing curriculum to enhance the science literacy of non-science majors Appropriate and inappropriate use of Lewis structures in general chemistry  The Chemistry Summer Undergraduate Research Program Understanding factors that affect the rate of reduction of ClO2 and ClO2- by ferrous ion.   The use of chlorine to disinfect drinking water results in the production of undesirable disinfection by-products (DBPs) such as trihalomethanes (THMs). As an alternative to chlorine, chlorine dioxide, ClO2, can be used. The use of ClO2 does not result in the formation of THMs. However, inorganic DBPs are produced, including chlorite ion, ClO2-, and chlorate ion, ClO3-. Several methods of removing ClO2- from water treated with ClO2 have been proposed. These methods include addition of iron(II) salts, sodium thiosulfate, sodium sulfite and sulfur dioxide. Of these substances, only iron(II) ion efficiently produced acceptable products. This reaction is the subject of this study. The equation for the reaction is: 2 H2O + ClO2- + 4 Fe2+ --> 4 FeOH2+ + Cl- The factors that affect the rate of reduction of ClO2- over the pH range from 0 to 1.5 and at high ionic strength (3.0 M) have been reported by other workers. Dr. Purser’s research examines the factors that affect the rate of the iron(II)-chlorite and iron(II)-chlorine dioxide reactions over a more natural pH range, ionic strength, and condition encountered by the water works industry.   Quantifying the ability of melatonin to behave as an antioxidant.   There is widespread belief in the general public that melatonin acts as an anti-aging compound. This belief comes from studies that show that, under certain conditions, melatonin can act as an antioxidant. Activated neutrophils produce hypochlorous acid, HOCl, as a byproduct of the release of myeloperoxidase. It has been suggested that melatonin can serve as a biological antioxidant HOCl. Critical to understanding the effectiveness of melatonin as an antioxidant is an understanding of the factors that affect the rate at which it can deactivate hypochlorous acid. Dr. Purser’s research is focusing on understanding these factors. The research also examines the significance of the structural features of the melatonin molecule on the rate of deactivation of hypochlorous acid. Developing curriculum to enhance the science literacy of non-science majors.   Many colleges and universities recognize the need for a change in the way science education is delivered, especially to non-science majors. Dr. Purser's research involves finding ways to develop innovative curricula and courses for these students. The research emphasizes modifying the faculty reward system to promote the changing of outdated operating policies and procedures, and the building effective partnerships across disciplines. The research investigates ways to modify the academic infrastructure, and make it more accommodating to the non-science student. Of particular interest is the integration of research into educational activities of the non-scientist. Furthermore Dr. Purser’s research involves the reform of undergraduate education across the institution, and promotes programs that can be taught at two-year and four-year colleges, comprehensive universities, doctoral universities, and at the much maligned research-intensive universities. Improving in the teaching of science, mathematics, engineering, and technology to all students requires that high academic standards must be upheld, and that the maximum potential of each and every individual student be developed. To this end, Dr. Purser is leading The University of Tulsa in an effort to reform science education for non-science majors. Research-based courses are being developed specifically for non-science majors. The courses will develop a strong foundation in mathematics, science and engineering, coordinate an interdisciplinary undergraduate learning environment and integrate science with non-scientific methods and perspectives.   Appropriate and inappropriate use of Lewis structures in general chemistry.   The drawing of appropriate Lewis structures is an important skill developed in general chemistry. Many chemical educators use Lewis structures to predict the electronic structure of molecules. Dr. Purser's research examines the relationship between Lewis dot structures and electron structure obtained from quantum mechanical calculations. In general, the research shows that Lewis structures are classical models of bonding and do not predict electronic structure, but the power of Lewis structures to predict molecular structure can be retained. The research further examines what Lewis allow the accurate prediction of molecular properties, such as polarity, bond length, bond angle and bond strength, and the role of formal charges within the molecule. The research examines the meaning of the, so called, "expanded octet."